xref: /openbmc/linux/fs/ceph/caps.c (revision d3383a8e)
13d14c5d2SYehuda Sadeh #include <linux/ceph/ceph_debug.h>
2a8599bd8SSage Weil 
3a8599bd8SSage Weil #include <linux/fs.h>
4a8599bd8SSage Weil #include <linux/kernel.h>
5a8599bd8SSage Weil #include <linux/sched.h>
65a0e3ad6STejun Heo #include <linux/slab.h>
7a8599bd8SSage Weil #include <linux/vmalloc.h>
8a8599bd8SSage Weil #include <linux/wait.h>
9f1a3d572SStephen Rothwell #include <linux/writeback.h>
10a8599bd8SSage Weil 
11a8599bd8SSage Weil #include "super.h"
123d14c5d2SYehuda Sadeh #include "mds_client.h"
1399ccbd22SMilosz Tanski #include "cache.h"
143d14c5d2SYehuda Sadeh #include <linux/ceph/decode.h>
153d14c5d2SYehuda Sadeh #include <linux/ceph/messenger.h>
16a8599bd8SSage Weil 
17a8599bd8SSage Weil /*
18a8599bd8SSage Weil  * Capability management
19a8599bd8SSage Weil  *
20a8599bd8SSage Weil  * The Ceph metadata servers control client access to inode metadata
21a8599bd8SSage Weil  * and file data by issuing capabilities, granting clients permission
22a8599bd8SSage Weil  * to read and/or write both inode field and file data to OSDs
23a8599bd8SSage Weil  * (storage nodes).  Each capability consists of a set of bits
24a8599bd8SSage Weil  * indicating which operations are allowed.
25a8599bd8SSage Weil  *
26a8599bd8SSage Weil  * If the client holds a *_SHARED cap, the client has a coherent value
27a8599bd8SSage Weil  * that can be safely read from the cached inode.
28a8599bd8SSage Weil  *
29a8599bd8SSage Weil  * In the case of a *_EXCL (exclusive) or FILE_WR capabilities, the
30a8599bd8SSage Weil  * client is allowed to change inode attributes (e.g., file size,
31a8599bd8SSage Weil  * mtime), note its dirty state in the ceph_cap, and asynchronously
32a8599bd8SSage Weil  * flush that metadata change to the MDS.
33a8599bd8SSage Weil  *
34a8599bd8SSage Weil  * In the event of a conflicting operation (perhaps by another
35a8599bd8SSage Weil  * client), the MDS will revoke the conflicting client capabilities.
36a8599bd8SSage Weil  *
37a8599bd8SSage Weil  * In order for a client to cache an inode, it must hold a capability
38a8599bd8SSage Weil  * with at least one MDS server.  When inodes are released, release
39a8599bd8SSage Weil  * notifications are batched and periodically sent en masse to the MDS
40a8599bd8SSage Weil  * cluster to release server state.
41a8599bd8SSage Weil  */
42a8599bd8SSage Weil 
43a8599bd8SSage Weil 
44a8599bd8SSage Weil /*
45a8599bd8SSage Weil  * Generate readable cap strings for debugging output.
46a8599bd8SSage Weil  */
47a8599bd8SSage Weil #define MAX_CAP_STR 20
48a8599bd8SSage Weil static char cap_str[MAX_CAP_STR][40];
49a8599bd8SSage Weil static DEFINE_SPINLOCK(cap_str_lock);
50a8599bd8SSage Weil static int last_cap_str;
51a8599bd8SSage Weil 
52a8599bd8SSage Weil static char *gcap_string(char *s, int c)
53a8599bd8SSage Weil {
54a8599bd8SSage Weil 	if (c & CEPH_CAP_GSHARED)
55a8599bd8SSage Weil 		*s++ = 's';
56a8599bd8SSage Weil 	if (c & CEPH_CAP_GEXCL)
57a8599bd8SSage Weil 		*s++ = 'x';
58a8599bd8SSage Weil 	if (c & CEPH_CAP_GCACHE)
59a8599bd8SSage Weil 		*s++ = 'c';
60a8599bd8SSage Weil 	if (c & CEPH_CAP_GRD)
61a8599bd8SSage Weil 		*s++ = 'r';
62a8599bd8SSage Weil 	if (c & CEPH_CAP_GWR)
63a8599bd8SSage Weil 		*s++ = 'w';
64a8599bd8SSage Weil 	if (c & CEPH_CAP_GBUFFER)
65a8599bd8SSage Weil 		*s++ = 'b';
66a8599bd8SSage Weil 	if (c & CEPH_CAP_GLAZYIO)
67a8599bd8SSage Weil 		*s++ = 'l';
68a8599bd8SSage Weil 	return s;
69a8599bd8SSage Weil }
70a8599bd8SSage Weil 
71a8599bd8SSage Weil const char *ceph_cap_string(int caps)
72a8599bd8SSage Weil {
73a8599bd8SSage Weil 	int i;
74a8599bd8SSage Weil 	char *s;
75a8599bd8SSage Weil 	int c;
76a8599bd8SSage Weil 
77a8599bd8SSage Weil 	spin_lock(&cap_str_lock);
78a8599bd8SSage Weil 	i = last_cap_str++;
79a8599bd8SSage Weil 	if (last_cap_str == MAX_CAP_STR)
80a8599bd8SSage Weil 		last_cap_str = 0;
81a8599bd8SSage Weil 	spin_unlock(&cap_str_lock);
82a8599bd8SSage Weil 
83a8599bd8SSage Weil 	s = cap_str[i];
84a8599bd8SSage Weil 
85a8599bd8SSage Weil 	if (caps & CEPH_CAP_PIN)
86a8599bd8SSage Weil 		*s++ = 'p';
87a8599bd8SSage Weil 
88a8599bd8SSage Weil 	c = (caps >> CEPH_CAP_SAUTH) & 3;
89a8599bd8SSage Weil 	if (c) {
90a8599bd8SSage Weil 		*s++ = 'A';
91a8599bd8SSage Weil 		s = gcap_string(s, c);
92a8599bd8SSage Weil 	}
93a8599bd8SSage Weil 
94a8599bd8SSage Weil 	c = (caps >> CEPH_CAP_SLINK) & 3;
95a8599bd8SSage Weil 	if (c) {
96a8599bd8SSage Weil 		*s++ = 'L';
97a8599bd8SSage Weil 		s = gcap_string(s, c);
98a8599bd8SSage Weil 	}
99a8599bd8SSage Weil 
100a8599bd8SSage Weil 	c = (caps >> CEPH_CAP_SXATTR) & 3;
101a8599bd8SSage Weil 	if (c) {
102a8599bd8SSage Weil 		*s++ = 'X';
103a8599bd8SSage Weil 		s = gcap_string(s, c);
104a8599bd8SSage Weil 	}
105a8599bd8SSage Weil 
106a8599bd8SSage Weil 	c = caps >> CEPH_CAP_SFILE;
107a8599bd8SSage Weil 	if (c) {
108a8599bd8SSage Weil 		*s++ = 'F';
109a8599bd8SSage Weil 		s = gcap_string(s, c);
110a8599bd8SSage Weil 	}
111a8599bd8SSage Weil 
112a8599bd8SSage Weil 	if (s == cap_str[i])
113a8599bd8SSage Weil 		*s++ = '-';
114a8599bd8SSage Weil 	*s = 0;
115a8599bd8SSage Weil 	return cap_str[i];
116a8599bd8SSage Weil }
117a8599bd8SSage Weil 
11837151668SYehuda Sadeh void ceph_caps_init(struct ceph_mds_client *mdsc)
119a8599bd8SSage Weil {
12037151668SYehuda Sadeh 	INIT_LIST_HEAD(&mdsc->caps_list);
12137151668SYehuda Sadeh 	spin_lock_init(&mdsc->caps_list_lock);
122a8599bd8SSage Weil }
123a8599bd8SSage Weil 
12437151668SYehuda Sadeh void ceph_caps_finalize(struct ceph_mds_client *mdsc)
125a8599bd8SSage Weil {
126a8599bd8SSage Weil 	struct ceph_cap *cap;
127a8599bd8SSage Weil 
12837151668SYehuda Sadeh 	spin_lock(&mdsc->caps_list_lock);
12937151668SYehuda Sadeh 	while (!list_empty(&mdsc->caps_list)) {
13037151668SYehuda Sadeh 		cap = list_first_entry(&mdsc->caps_list,
13137151668SYehuda Sadeh 				       struct ceph_cap, caps_item);
132a8599bd8SSage Weil 		list_del(&cap->caps_item);
133a8599bd8SSage Weil 		kmem_cache_free(ceph_cap_cachep, cap);
134a8599bd8SSage Weil 	}
13537151668SYehuda Sadeh 	mdsc->caps_total_count = 0;
13637151668SYehuda Sadeh 	mdsc->caps_avail_count = 0;
13737151668SYehuda Sadeh 	mdsc->caps_use_count = 0;
13837151668SYehuda Sadeh 	mdsc->caps_reserve_count = 0;
13937151668SYehuda Sadeh 	mdsc->caps_min_count = 0;
14037151668SYehuda Sadeh 	spin_unlock(&mdsc->caps_list_lock);
14185ccce43SSage Weil }
14285ccce43SSage Weil 
14337151668SYehuda Sadeh void ceph_adjust_min_caps(struct ceph_mds_client *mdsc, int delta)
14485ccce43SSage Weil {
14537151668SYehuda Sadeh 	spin_lock(&mdsc->caps_list_lock);
14637151668SYehuda Sadeh 	mdsc->caps_min_count += delta;
14737151668SYehuda Sadeh 	BUG_ON(mdsc->caps_min_count < 0);
14837151668SYehuda Sadeh 	spin_unlock(&mdsc->caps_list_lock);
149a8599bd8SSage Weil }
150a8599bd8SSage Weil 
15193faca6eSmajianpeng void ceph_reserve_caps(struct ceph_mds_client *mdsc,
15237151668SYehuda Sadeh 		      struct ceph_cap_reservation *ctx, int need)
153a8599bd8SSage Weil {
154a8599bd8SSage Weil 	int i;
155a8599bd8SSage Weil 	struct ceph_cap *cap;
156a8599bd8SSage Weil 	int have;
157a8599bd8SSage Weil 	int alloc = 0;
158a8599bd8SSage Weil 	LIST_HEAD(newcaps);
159a8599bd8SSage Weil 
160a8599bd8SSage Weil 	dout("reserve caps ctx=%p need=%d\n", ctx, need);
161a8599bd8SSage Weil 
162a8599bd8SSage Weil 	/* first reserve any caps that are already allocated */
16337151668SYehuda Sadeh 	spin_lock(&mdsc->caps_list_lock);
16437151668SYehuda Sadeh 	if (mdsc->caps_avail_count >= need)
165a8599bd8SSage Weil 		have = need;
166a8599bd8SSage Weil 	else
16737151668SYehuda Sadeh 		have = mdsc->caps_avail_count;
16837151668SYehuda Sadeh 	mdsc->caps_avail_count -= have;
16937151668SYehuda Sadeh 	mdsc->caps_reserve_count += have;
17037151668SYehuda Sadeh 	BUG_ON(mdsc->caps_total_count != mdsc->caps_use_count +
17137151668SYehuda Sadeh 					 mdsc->caps_reserve_count +
17237151668SYehuda Sadeh 					 mdsc->caps_avail_count);
17337151668SYehuda Sadeh 	spin_unlock(&mdsc->caps_list_lock);
174a8599bd8SSage Weil 
175a8599bd8SSage Weil 	for (i = have; i < need; i++) {
176a8599bd8SSage Weil 		cap = kmem_cache_alloc(ceph_cap_cachep, GFP_NOFS);
17793faca6eSmajianpeng 		if (!cap)
17893faca6eSmajianpeng 			break;
179a8599bd8SSage Weil 		list_add(&cap->caps_item, &newcaps);
180a8599bd8SSage Weil 		alloc++;
181a8599bd8SSage Weil 	}
18293faca6eSmajianpeng 	/* we didn't manage to reserve as much as we needed */
18393faca6eSmajianpeng 	if (have + alloc != need)
18493faca6eSmajianpeng 		pr_warn("reserve caps ctx=%p ENOMEM need=%d got=%d\n",
18593faca6eSmajianpeng 			ctx, need, have + alloc);
186a8599bd8SSage Weil 
18737151668SYehuda Sadeh 	spin_lock(&mdsc->caps_list_lock);
18837151668SYehuda Sadeh 	mdsc->caps_total_count += alloc;
18937151668SYehuda Sadeh 	mdsc->caps_reserve_count += alloc;
19037151668SYehuda Sadeh 	list_splice(&newcaps, &mdsc->caps_list);
191a8599bd8SSage Weil 
19237151668SYehuda Sadeh 	BUG_ON(mdsc->caps_total_count != mdsc->caps_use_count +
19337151668SYehuda Sadeh 					 mdsc->caps_reserve_count +
19437151668SYehuda Sadeh 					 mdsc->caps_avail_count);
19537151668SYehuda Sadeh 	spin_unlock(&mdsc->caps_list_lock);
196a8599bd8SSage Weil 
197a8599bd8SSage Weil 	ctx->count = need;
198a8599bd8SSage Weil 	dout("reserve caps ctx=%p %d = %d used + %d resv + %d avail\n",
19937151668SYehuda Sadeh 	     ctx, mdsc->caps_total_count, mdsc->caps_use_count,
20037151668SYehuda Sadeh 	     mdsc->caps_reserve_count, mdsc->caps_avail_count);
201a8599bd8SSage Weil }
202a8599bd8SSage Weil 
20337151668SYehuda Sadeh int ceph_unreserve_caps(struct ceph_mds_client *mdsc,
20437151668SYehuda Sadeh 			struct ceph_cap_reservation *ctx)
205a8599bd8SSage Weil {
206a8599bd8SSage Weil 	dout("unreserve caps ctx=%p count=%d\n", ctx, ctx->count);
207a8599bd8SSage Weil 	if (ctx->count) {
20837151668SYehuda Sadeh 		spin_lock(&mdsc->caps_list_lock);
20937151668SYehuda Sadeh 		BUG_ON(mdsc->caps_reserve_count < ctx->count);
21037151668SYehuda Sadeh 		mdsc->caps_reserve_count -= ctx->count;
21137151668SYehuda Sadeh 		mdsc->caps_avail_count += ctx->count;
212a8599bd8SSage Weil 		ctx->count = 0;
213a8599bd8SSage Weil 		dout("unreserve caps %d = %d used + %d resv + %d avail\n",
21437151668SYehuda Sadeh 		     mdsc->caps_total_count, mdsc->caps_use_count,
21537151668SYehuda Sadeh 		     mdsc->caps_reserve_count, mdsc->caps_avail_count);
21637151668SYehuda Sadeh 		BUG_ON(mdsc->caps_total_count != mdsc->caps_use_count +
21737151668SYehuda Sadeh 						 mdsc->caps_reserve_count +
21837151668SYehuda Sadeh 						 mdsc->caps_avail_count);
21937151668SYehuda Sadeh 		spin_unlock(&mdsc->caps_list_lock);
220a8599bd8SSage Weil 	}
221a8599bd8SSage Weil 	return 0;
222a8599bd8SSage Weil }
223a8599bd8SSage Weil 
224d9df2783SYan, Zheng struct ceph_cap *ceph_get_cap(struct ceph_mds_client *mdsc,
22537151668SYehuda Sadeh 			      struct ceph_cap_reservation *ctx)
226a8599bd8SSage Weil {
227a8599bd8SSage Weil 	struct ceph_cap *cap = NULL;
228a8599bd8SSage Weil 
229a8599bd8SSage Weil 	/* temporary, until we do something about cap import/export */
230443b3760SSage Weil 	if (!ctx) {
231443b3760SSage Weil 		cap = kmem_cache_alloc(ceph_cap_cachep, GFP_NOFS);
232443b3760SSage Weil 		if (cap) {
2334d1d0534SYan, Zheng 			spin_lock(&mdsc->caps_list_lock);
23437151668SYehuda Sadeh 			mdsc->caps_use_count++;
23537151668SYehuda Sadeh 			mdsc->caps_total_count++;
2364d1d0534SYan, Zheng 			spin_unlock(&mdsc->caps_list_lock);
237443b3760SSage Weil 		}
238443b3760SSage Weil 		return cap;
239443b3760SSage Weil 	}
240a8599bd8SSage Weil 
24137151668SYehuda Sadeh 	spin_lock(&mdsc->caps_list_lock);
242a8599bd8SSage Weil 	dout("get_cap ctx=%p (%d) %d = %d used + %d resv + %d avail\n",
24337151668SYehuda Sadeh 	     ctx, ctx->count, mdsc->caps_total_count, mdsc->caps_use_count,
24437151668SYehuda Sadeh 	     mdsc->caps_reserve_count, mdsc->caps_avail_count);
245a8599bd8SSage Weil 	BUG_ON(!ctx->count);
24637151668SYehuda Sadeh 	BUG_ON(ctx->count > mdsc->caps_reserve_count);
24737151668SYehuda Sadeh 	BUG_ON(list_empty(&mdsc->caps_list));
248a8599bd8SSage Weil 
249a8599bd8SSage Weil 	ctx->count--;
25037151668SYehuda Sadeh 	mdsc->caps_reserve_count--;
25137151668SYehuda Sadeh 	mdsc->caps_use_count++;
252a8599bd8SSage Weil 
25337151668SYehuda Sadeh 	cap = list_first_entry(&mdsc->caps_list, struct ceph_cap, caps_item);
254a8599bd8SSage Weil 	list_del(&cap->caps_item);
255a8599bd8SSage Weil 
25637151668SYehuda Sadeh 	BUG_ON(mdsc->caps_total_count != mdsc->caps_use_count +
25737151668SYehuda Sadeh 	       mdsc->caps_reserve_count + mdsc->caps_avail_count);
25837151668SYehuda Sadeh 	spin_unlock(&mdsc->caps_list_lock);
259a8599bd8SSage Weil 	return cap;
260a8599bd8SSage Weil }
261a8599bd8SSage Weil 
26237151668SYehuda Sadeh void ceph_put_cap(struct ceph_mds_client *mdsc, struct ceph_cap *cap)
263a8599bd8SSage Weil {
26437151668SYehuda Sadeh 	spin_lock(&mdsc->caps_list_lock);
2657c1332b8SSage Weil 	dout("put_cap %p %d = %d used + %d resv + %d avail\n",
26637151668SYehuda Sadeh 	     cap, mdsc->caps_total_count, mdsc->caps_use_count,
26737151668SYehuda Sadeh 	     mdsc->caps_reserve_count, mdsc->caps_avail_count);
26837151668SYehuda Sadeh 	mdsc->caps_use_count--;
269a8599bd8SSage Weil 	/*
27085ccce43SSage Weil 	 * Keep some preallocated caps around (ceph_min_count), to
27185ccce43SSage Weil 	 * avoid lots of free/alloc churn.
272a8599bd8SSage Weil 	 */
27337151668SYehuda Sadeh 	if (mdsc->caps_avail_count >= mdsc->caps_reserve_count +
27437151668SYehuda Sadeh 				      mdsc->caps_min_count) {
27537151668SYehuda Sadeh 		mdsc->caps_total_count--;
276a8599bd8SSage Weil 		kmem_cache_free(ceph_cap_cachep, cap);
277a8599bd8SSage Weil 	} else {
27837151668SYehuda Sadeh 		mdsc->caps_avail_count++;
27937151668SYehuda Sadeh 		list_add(&cap->caps_item, &mdsc->caps_list);
280a8599bd8SSage Weil 	}
281a8599bd8SSage Weil 
28237151668SYehuda Sadeh 	BUG_ON(mdsc->caps_total_count != mdsc->caps_use_count +
28337151668SYehuda Sadeh 	       mdsc->caps_reserve_count + mdsc->caps_avail_count);
28437151668SYehuda Sadeh 	spin_unlock(&mdsc->caps_list_lock);
285a8599bd8SSage Weil }
286a8599bd8SSage Weil 
2873d14c5d2SYehuda Sadeh void ceph_reservation_status(struct ceph_fs_client *fsc,
28885ccce43SSage Weil 			     int *total, int *avail, int *used, int *reserved,
28985ccce43SSage Weil 			     int *min)
290a8599bd8SSage Weil {
2913d14c5d2SYehuda Sadeh 	struct ceph_mds_client *mdsc = fsc->mdsc;
29237151668SYehuda Sadeh 
293a8599bd8SSage Weil 	if (total)
29437151668SYehuda Sadeh 		*total = mdsc->caps_total_count;
295a8599bd8SSage Weil 	if (avail)
29637151668SYehuda Sadeh 		*avail = mdsc->caps_avail_count;
297a8599bd8SSage Weil 	if (used)
29837151668SYehuda Sadeh 		*used = mdsc->caps_use_count;
299a8599bd8SSage Weil 	if (reserved)
30037151668SYehuda Sadeh 		*reserved = mdsc->caps_reserve_count;
30185ccce43SSage Weil 	if (min)
30237151668SYehuda Sadeh 		*min = mdsc->caps_min_count;
303a8599bd8SSage Weil }
304a8599bd8SSage Weil 
305a8599bd8SSage Weil /*
306a8599bd8SSage Weil  * Find ceph_cap for given mds, if any.
307a8599bd8SSage Weil  *
308be655596SSage Weil  * Called with i_ceph_lock held.
309a8599bd8SSage Weil  */
310a8599bd8SSage Weil static struct ceph_cap *__get_cap_for_mds(struct ceph_inode_info *ci, int mds)
311a8599bd8SSage Weil {
312a8599bd8SSage Weil 	struct ceph_cap *cap;
313a8599bd8SSage Weil 	struct rb_node *n = ci->i_caps.rb_node;
314a8599bd8SSage Weil 
315a8599bd8SSage Weil 	while (n) {
316a8599bd8SSage Weil 		cap = rb_entry(n, struct ceph_cap, ci_node);
317a8599bd8SSage Weil 		if (mds < cap->mds)
318a8599bd8SSage Weil 			n = n->rb_left;
319a8599bd8SSage Weil 		else if (mds > cap->mds)
320a8599bd8SSage Weil 			n = n->rb_right;
321a8599bd8SSage Weil 		else
322a8599bd8SSage Weil 			return cap;
323a8599bd8SSage Weil 	}
324a8599bd8SSage Weil 	return NULL;
325a8599bd8SSage Weil }
326a8599bd8SSage Weil 
3272bc50259SGreg Farnum struct ceph_cap *ceph_get_cap_for_mds(struct ceph_inode_info *ci, int mds)
3282bc50259SGreg Farnum {
3292bc50259SGreg Farnum 	struct ceph_cap *cap;
3302bc50259SGreg Farnum 
331be655596SSage Weil 	spin_lock(&ci->i_ceph_lock);
3322bc50259SGreg Farnum 	cap = __get_cap_for_mds(ci, mds);
333be655596SSage Weil 	spin_unlock(&ci->i_ceph_lock);
3342bc50259SGreg Farnum 	return cap;
3352bc50259SGreg Farnum }
3362bc50259SGreg Farnum 
337a8599bd8SSage Weil /*
33833caad32SSage Weil  * Return id of any MDS with a cap, preferably FILE_WR|BUFFER|EXCL, else -1.
339a8599bd8SSage Weil  */
340ca81f3f6SSage Weil static int __ceph_get_cap_mds(struct ceph_inode_info *ci)
341a8599bd8SSage Weil {
342a8599bd8SSage Weil 	struct ceph_cap *cap;
343a8599bd8SSage Weil 	int mds = -1;
344a8599bd8SSage Weil 	struct rb_node *p;
345a8599bd8SSage Weil 
34633caad32SSage Weil 	/* prefer mds with WR|BUFFER|EXCL caps */
347a8599bd8SSage Weil 	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
348a8599bd8SSage Weil 		cap = rb_entry(p, struct ceph_cap, ci_node);
349a8599bd8SSage Weil 		mds = cap->mds;
350a8599bd8SSage Weil 		if (cap->issued & (CEPH_CAP_FILE_WR |
351a8599bd8SSage Weil 				   CEPH_CAP_FILE_BUFFER |
352a8599bd8SSage Weil 				   CEPH_CAP_FILE_EXCL))
353a8599bd8SSage Weil 			break;
354a8599bd8SSage Weil 	}
355a8599bd8SSage Weil 	return mds;
356a8599bd8SSage Weil }
357a8599bd8SSage Weil 
358a8599bd8SSage Weil int ceph_get_cap_mds(struct inode *inode)
359a8599bd8SSage Weil {
360be655596SSage Weil 	struct ceph_inode_info *ci = ceph_inode(inode);
361a8599bd8SSage Weil 	int mds;
362be655596SSage Weil 	spin_lock(&ci->i_ceph_lock);
363ca81f3f6SSage Weil 	mds = __ceph_get_cap_mds(ceph_inode(inode));
364be655596SSage Weil 	spin_unlock(&ci->i_ceph_lock);
365a8599bd8SSage Weil 	return mds;
366a8599bd8SSage Weil }
367a8599bd8SSage Weil 
368a8599bd8SSage Weil /*
369be655596SSage Weil  * Called under i_ceph_lock.
370a8599bd8SSage Weil  */
371a8599bd8SSage Weil static void __insert_cap_node(struct ceph_inode_info *ci,
372a8599bd8SSage Weil 			      struct ceph_cap *new)
373a8599bd8SSage Weil {
374a8599bd8SSage Weil 	struct rb_node **p = &ci->i_caps.rb_node;
375a8599bd8SSage Weil 	struct rb_node *parent = NULL;
376a8599bd8SSage Weil 	struct ceph_cap *cap = NULL;
377a8599bd8SSage Weil 
378a8599bd8SSage Weil 	while (*p) {
379a8599bd8SSage Weil 		parent = *p;
380a8599bd8SSage Weil 		cap = rb_entry(parent, struct ceph_cap, ci_node);
381a8599bd8SSage Weil 		if (new->mds < cap->mds)
382a8599bd8SSage Weil 			p = &(*p)->rb_left;
383a8599bd8SSage Weil 		else if (new->mds > cap->mds)
384a8599bd8SSage Weil 			p = &(*p)->rb_right;
385a8599bd8SSage Weil 		else
386a8599bd8SSage Weil 			BUG();
387a8599bd8SSage Weil 	}
388a8599bd8SSage Weil 
389a8599bd8SSage Weil 	rb_link_node(&new->ci_node, parent, p);
390a8599bd8SSage Weil 	rb_insert_color(&new->ci_node, &ci->i_caps);
391a8599bd8SSage Weil }
392a8599bd8SSage Weil 
393a8599bd8SSage Weil /*
394a8599bd8SSage Weil  * (re)set cap hold timeouts, which control the delayed release
395a8599bd8SSage Weil  * of unused caps back to the MDS.  Should be called on cap use.
396a8599bd8SSage Weil  */
397a8599bd8SSage Weil static void __cap_set_timeouts(struct ceph_mds_client *mdsc,
398a8599bd8SSage Weil 			       struct ceph_inode_info *ci)
399a8599bd8SSage Weil {
4003d14c5d2SYehuda Sadeh 	struct ceph_mount_options *ma = mdsc->fsc->mount_options;
401a8599bd8SSage Weil 
402a8599bd8SSage Weil 	ci->i_hold_caps_min = round_jiffies(jiffies +
403a8599bd8SSage Weil 					    ma->caps_wanted_delay_min * HZ);
404a8599bd8SSage Weil 	ci->i_hold_caps_max = round_jiffies(jiffies +
405a8599bd8SSage Weil 					    ma->caps_wanted_delay_max * HZ);
406a8599bd8SSage Weil 	dout("__cap_set_timeouts %p min %lu max %lu\n", &ci->vfs_inode,
407a8599bd8SSage Weil 	     ci->i_hold_caps_min - jiffies, ci->i_hold_caps_max - jiffies);
408a8599bd8SSage Weil }
409a8599bd8SSage Weil 
410a8599bd8SSage Weil /*
411a8599bd8SSage Weil  * (Re)queue cap at the end of the delayed cap release list.
412a8599bd8SSage Weil  *
413a8599bd8SSage Weil  * If I_FLUSH is set, leave the inode at the front of the list.
414a8599bd8SSage Weil  *
415be655596SSage Weil  * Caller holds i_ceph_lock
416a8599bd8SSage Weil  *    -> we take mdsc->cap_delay_lock
417a8599bd8SSage Weil  */
418a8599bd8SSage Weil static void __cap_delay_requeue(struct ceph_mds_client *mdsc,
419a8599bd8SSage Weil 				struct ceph_inode_info *ci)
420a8599bd8SSage Weil {
421a8599bd8SSage Weil 	__cap_set_timeouts(mdsc, ci);
422a8599bd8SSage Weil 	dout("__cap_delay_requeue %p flags %d at %lu\n", &ci->vfs_inode,
423a8599bd8SSage Weil 	     ci->i_ceph_flags, ci->i_hold_caps_max);
424a8599bd8SSage Weil 	if (!mdsc->stopping) {
425a8599bd8SSage Weil 		spin_lock(&mdsc->cap_delay_lock);
426a8599bd8SSage Weil 		if (!list_empty(&ci->i_cap_delay_list)) {
427a8599bd8SSage Weil 			if (ci->i_ceph_flags & CEPH_I_FLUSH)
428a8599bd8SSage Weil 				goto no_change;
429a8599bd8SSage Weil 			list_del_init(&ci->i_cap_delay_list);
430a8599bd8SSage Weil 		}
431a8599bd8SSage Weil 		list_add_tail(&ci->i_cap_delay_list, &mdsc->cap_delay_list);
432a8599bd8SSage Weil no_change:
433a8599bd8SSage Weil 		spin_unlock(&mdsc->cap_delay_lock);
434a8599bd8SSage Weil 	}
435a8599bd8SSage Weil }
436a8599bd8SSage Weil 
437a8599bd8SSage Weil /*
438a8599bd8SSage Weil  * Queue an inode for immediate writeback.  Mark inode with I_FLUSH,
439a8599bd8SSage Weil  * indicating we should send a cap message to flush dirty metadata
440a8599bd8SSage Weil  * asap, and move to the front of the delayed cap list.
441a8599bd8SSage Weil  */
442a8599bd8SSage Weil static void __cap_delay_requeue_front(struct ceph_mds_client *mdsc,
443a8599bd8SSage Weil 				      struct ceph_inode_info *ci)
444a8599bd8SSage Weil {
445a8599bd8SSage Weil 	dout("__cap_delay_requeue_front %p\n", &ci->vfs_inode);
446a8599bd8SSage Weil 	spin_lock(&mdsc->cap_delay_lock);
447a8599bd8SSage Weil 	ci->i_ceph_flags |= CEPH_I_FLUSH;
448a8599bd8SSage Weil 	if (!list_empty(&ci->i_cap_delay_list))
449a8599bd8SSage Weil 		list_del_init(&ci->i_cap_delay_list);
450a8599bd8SSage Weil 	list_add(&ci->i_cap_delay_list, &mdsc->cap_delay_list);
451a8599bd8SSage Weil 	spin_unlock(&mdsc->cap_delay_lock);
452a8599bd8SSage Weil }
453a8599bd8SSage Weil 
454a8599bd8SSage Weil /*
455a8599bd8SSage Weil  * Cancel delayed work on cap.
456a8599bd8SSage Weil  *
457be655596SSage Weil  * Caller must hold i_ceph_lock.
458a8599bd8SSage Weil  */
459a8599bd8SSage Weil static void __cap_delay_cancel(struct ceph_mds_client *mdsc,
460a8599bd8SSage Weil 			       struct ceph_inode_info *ci)
461a8599bd8SSage Weil {
462a8599bd8SSage Weil 	dout("__cap_delay_cancel %p\n", &ci->vfs_inode);
463a8599bd8SSage Weil 	if (list_empty(&ci->i_cap_delay_list))
464a8599bd8SSage Weil 		return;
465a8599bd8SSage Weil 	spin_lock(&mdsc->cap_delay_lock);
466a8599bd8SSage Weil 	list_del_init(&ci->i_cap_delay_list);
467a8599bd8SSage Weil 	spin_unlock(&mdsc->cap_delay_lock);
468a8599bd8SSage Weil }
469a8599bd8SSage Weil 
470a8599bd8SSage Weil /*
471a8599bd8SSage Weil  * Common issue checks for add_cap, handle_cap_grant.
472a8599bd8SSage Weil  */
473a8599bd8SSage Weil static void __check_cap_issue(struct ceph_inode_info *ci, struct ceph_cap *cap,
474a8599bd8SSage Weil 			      unsigned issued)
475a8599bd8SSage Weil {
476a8599bd8SSage Weil 	unsigned had = __ceph_caps_issued(ci, NULL);
477a8599bd8SSage Weil 
478a8599bd8SSage Weil 	/*
479a8599bd8SSage Weil 	 * Each time we receive FILE_CACHE anew, we increment
480a8599bd8SSage Weil 	 * i_rdcache_gen.
481a8599bd8SSage Weil 	 */
4822962507cSSage Weil 	if ((issued & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)) &&
48399ccbd22SMilosz Tanski 	    (had & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)) == 0) {
484a8599bd8SSage Weil 		ci->i_rdcache_gen++;
48599ccbd22SMilosz Tanski 	}
486a8599bd8SSage Weil 
487a8599bd8SSage Weil 	/*
4882f276c51SYan, Zheng 	 * if we are newly issued FILE_SHARED, mark dir not complete; we
489a8599bd8SSage Weil 	 * don't know what happened to this directory while we didn't
490a8599bd8SSage Weil 	 * have the cap.
491a8599bd8SSage Weil 	 */
492a8599bd8SSage Weil 	if ((issued & CEPH_CAP_FILE_SHARED) &&
493a8599bd8SSage Weil 	    (had & CEPH_CAP_FILE_SHARED) == 0) {
494a8599bd8SSage Weil 		ci->i_shared_gen++;
495a8673d61SYan, Zheng 		if (S_ISDIR(ci->vfs_inode.i_mode)) {
496a8673d61SYan, Zheng 			dout(" marking %p NOT complete\n", &ci->vfs_inode);
4972f276c51SYan, Zheng 			__ceph_dir_clear_complete(ci);
498a8673d61SYan, Zheng 		}
499a8599bd8SSage Weil 	}
500a8599bd8SSage Weil }
501a8599bd8SSage Weil 
502a8599bd8SSage Weil /*
503a8599bd8SSage Weil  * Add a capability under the given MDS session.
504a8599bd8SSage Weil  *
505a8599bd8SSage Weil  * Caller should hold session snap_rwsem (read) and s_mutex.
506a8599bd8SSage Weil  *
507a8599bd8SSage Weil  * @fmode is the open file mode, if we are opening a file, otherwise
508a8599bd8SSage Weil  * it is < 0.  (This is so we can atomically add the cap and add an
509a8599bd8SSage Weil  * open file reference to it.)
510a8599bd8SSage Weil  */
511d9df2783SYan, Zheng void ceph_add_cap(struct inode *inode,
512a8599bd8SSage Weil 		  struct ceph_mds_session *session, u64 cap_id,
513a8599bd8SSage Weil 		  int fmode, unsigned issued, unsigned wanted,
514a8599bd8SSage Weil 		  unsigned seq, unsigned mseq, u64 realmino, int flags,
515d9df2783SYan, Zheng 		  struct ceph_cap **new_cap)
516a8599bd8SSage Weil {
5173d14c5d2SYehuda Sadeh 	struct ceph_mds_client *mdsc = ceph_inode_to_client(inode)->mdsc;
518a8599bd8SSage Weil 	struct ceph_inode_info *ci = ceph_inode(inode);
519a8599bd8SSage Weil 	struct ceph_cap *cap;
520a8599bd8SSage Weil 	int mds = session->s_mds;
521a8599bd8SSage Weil 	int actual_wanted;
522a8599bd8SSage Weil 
523a8599bd8SSage Weil 	dout("add_cap %p mds%d cap %llx %s seq %d\n", inode,
524a8599bd8SSage Weil 	     session->s_mds, cap_id, ceph_cap_string(issued), seq);
525a8599bd8SSage Weil 
526a8599bd8SSage Weil 	/*
527a8599bd8SSage Weil 	 * If we are opening the file, include file mode wanted bits
528a8599bd8SSage Weil 	 * in wanted.
529a8599bd8SSage Weil 	 */
530a8599bd8SSage Weil 	if (fmode >= 0)
531a8599bd8SSage Weil 		wanted |= ceph_caps_for_mode(fmode);
532a8599bd8SSage Weil 
533a8599bd8SSage Weil 	cap = __get_cap_for_mds(ci, mds);
534a8599bd8SSage Weil 	if (!cap) {
535d9df2783SYan, Zheng 		cap = *new_cap;
536d9df2783SYan, Zheng 		*new_cap = NULL;
537a8599bd8SSage Weil 
538a8599bd8SSage Weil 		cap->issued = 0;
539a8599bd8SSage Weil 		cap->implemented = 0;
540a8599bd8SSage Weil 		cap->mds = mds;
541a8599bd8SSage Weil 		cap->mds_wanted = 0;
542964266ccSYan, Zheng 		cap->mseq = 0;
543a8599bd8SSage Weil 
544a8599bd8SSage Weil 		cap->ci = ci;
545a8599bd8SSage Weil 		__insert_cap_node(ci, cap);
546a8599bd8SSage Weil 
547a8599bd8SSage Weil 		/* add to session cap list */
548a8599bd8SSage Weil 		cap->session = session;
549a8599bd8SSage Weil 		spin_lock(&session->s_cap_lock);
550a8599bd8SSage Weil 		list_add_tail(&cap->session_caps, &session->s_caps);
551a8599bd8SSage Weil 		session->s_nr_caps++;
552a8599bd8SSage Weil 		spin_unlock(&session->s_cap_lock);
55311df2dfbSYan, Zheng 	} else {
55411df2dfbSYan, Zheng 		/*
55511df2dfbSYan, Zheng 		 * auth mds of the inode changed. we received the cap export
55611df2dfbSYan, Zheng 		 * message, but still haven't received the cap import message.
55711df2dfbSYan, Zheng 		 * handle_cap_export() updated the new auth MDS' cap.
55811df2dfbSYan, Zheng 		 *
55911df2dfbSYan, Zheng 		 * "ceph_seq_cmp(seq, cap->seq) <= 0" means we are processing
56011df2dfbSYan, Zheng 		 * a message that was send before the cap import message. So
56111df2dfbSYan, Zheng 		 * don't remove caps.
56211df2dfbSYan, Zheng 		 */
56311df2dfbSYan, Zheng 		if (ceph_seq_cmp(seq, cap->seq) <= 0) {
56411df2dfbSYan, Zheng 			WARN_ON(cap != ci->i_auth_cap);
56511df2dfbSYan, Zheng 			WARN_ON(cap->cap_id != cap_id);
56611df2dfbSYan, Zheng 			seq = cap->seq;
56711df2dfbSYan, Zheng 			mseq = cap->mseq;
56811df2dfbSYan, Zheng 			issued |= cap->issued;
56911df2dfbSYan, Zheng 			flags |= CEPH_CAP_FLAG_AUTH;
57011df2dfbSYan, Zheng 		}
57111df2dfbSYan, Zheng 	}
57211df2dfbSYan, Zheng 
573a8599bd8SSage Weil 	if (!ci->i_snap_realm) {
574a8599bd8SSage Weil 		/*
575a8599bd8SSage Weil 		 * add this inode to the appropriate snap realm
576a8599bd8SSage Weil 		 */
577a8599bd8SSage Weil 		struct ceph_snap_realm *realm = ceph_lookup_snap_realm(mdsc,
578a8599bd8SSage Weil 							       realmino);
579a8599bd8SSage Weil 		if (realm) {
580a8599bd8SSage Weil 			spin_lock(&realm->inodes_with_caps_lock);
581a8599bd8SSage Weil 			ci->i_snap_realm = realm;
582a8599bd8SSage Weil 			list_add(&ci->i_snap_realm_item,
583a8599bd8SSage Weil 				 &realm->inodes_with_caps);
584a8599bd8SSage Weil 			spin_unlock(&realm->inodes_with_caps_lock);
585a8599bd8SSage Weil 		} else {
586a8599bd8SSage Weil 			pr_err("ceph_add_cap: couldn't find snap realm %llx\n",
587a8599bd8SSage Weil 			       realmino);
588b8cd07e7SSage Weil 			WARN_ON(!realm);
589a8599bd8SSage Weil 		}
590a8599bd8SSage Weil 	}
591a8599bd8SSage Weil 
592a8599bd8SSage Weil 	__check_cap_issue(ci, cap, issued);
593a8599bd8SSage Weil 
594a8599bd8SSage Weil 	/*
595a8599bd8SSage Weil 	 * If we are issued caps we don't want, or the mds' wanted
596a8599bd8SSage Weil 	 * value appears to be off, queue a check so we'll release
597a8599bd8SSage Weil 	 * later and/or update the mds wanted value.
598a8599bd8SSage Weil 	 */
599a8599bd8SSage Weil 	actual_wanted = __ceph_caps_wanted(ci);
600a8599bd8SSage Weil 	if ((wanted & ~actual_wanted) ||
601a8599bd8SSage Weil 	    (issued & ~actual_wanted & CEPH_CAP_ANY_WR)) {
602a8599bd8SSage Weil 		dout(" issued %s, mds wanted %s, actual %s, queueing\n",
603a8599bd8SSage Weil 		     ceph_cap_string(issued), ceph_cap_string(wanted),
604a8599bd8SSage Weil 		     ceph_cap_string(actual_wanted));
605a8599bd8SSage Weil 		__cap_delay_requeue(mdsc, ci);
606a8599bd8SSage Weil 	}
607a8599bd8SSage Weil 
608b8c2f3aeSYan, Zheng 	if (flags & CEPH_CAP_FLAG_AUTH) {
609b8c2f3aeSYan, Zheng 		if (ci->i_auth_cap == NULL ||
610d9ffc4f7SYan, Zheng 		    ceph_seq_cmp(ci->i_auth_cap->mseq, mseq) < 0) {
611a8599bd8SSage Weil 			ci->i_auth_cap = cap;
612d9ffc4f7SYan, Zheng 			cap->mds_wanted = wanted;
613d9ffc4f7SYan, Zheng 		}
61411df2dfbSYan, Zheng 	} else {
61511df2dfbSYan, Zheng 		WARN_ON(ci->i_auth_cap == cap);
6168a92a119SYan, Zheng 	}
617a8599bd8SSage Weil 
618a8599bd8SSage Weil 	dout("add_cap inode %p (%llx.%llx) cap %p %s now %s seq %d mds%d\n",
619a8599bd8SSage Weil 	     inode, ceph_vinop(inode), cap, ceph_cap_string(issued),
620a8599bd8SSage Weil 	     ceph_cap_string(issued|cap->issued), seq, mds);
621a8599bd8SSage Weil 	cap->cap_id = cap_id;
622a8599bd8SSage Weil 	cap->issued = issued;
623a8599bd8SSage Weil 	cap->implemented |= issued;
624d1b87809SYan, Zheng 	if (ceph_seq_cmp(mseq, cap->mseq) > 0)
625964266ccSYan, Zheng 		cap->mds_wanted = wanted;
626964266ccSYan, Zheng 	else
627a8599bd8SSage Weil 		cap->mds_wanted |= wanted;
628a8599bd8SSage Weil 	cap->seq = seq;
629a8599bd8SSage Weil 	cap->issue_seq = seq;
630a8599bd8SSage Weil 	cap->mseq = mseq;
631685f9a5dSSage Weil 	cap->cap_gen = session->s_cap_gen;
632a8599bd8SSage Weil 
633a8599bd8SSage Weil 	if (fmode >= 0)
634a8599bd8SSage Weil 		__ceph_get_fmode(ci, fmode);
635a8599bd8SSage Weil }
636a8599bd8SSage Weil 
637a8599bd8SSage Weil /*
638a8599bd8SSage Weil  * Return true if cap has not timed out and belongs to the current
639a8599bd8SSage Weil  * generation of the MDS session (i.e. has not gone 'stale' due to
640a8599bd8SSage Weil  * us losing touch with the mds).
641a8599bd8SSage Weil  */
642a8599bd8SSage Weil static int __cap_is_valid(struct ceph_cap *cap)
643a8599bd8SSage Weil {
644a8599bd8SSage Weil 	unsigned long ttl;
645cdac8303SSage Weil 	u32 gen;
646a8599bd8SSage Weil 
647d8fb02abSAlex Elder 	spin_lock(&cap->session->s_gen_ttl_lock);
648a8599bd8SSage Weil 	gen = cap->session->s_cap_gen;
649a8599bd8SSage Weil 	ttl = cap->session->s_cap_ttl;
650d8fb02abSAlex Elder 	spin_unlock(&cap->session->s_gen_ttl_lock);
651a8599bd8SSage Weil 
652685f9a5dSSage Weil 	if (cap->cap_gen < gen || time_after_eq(jiffies, ttl)) {
653a8599bd8SSage Weil 		dout("__cap_is_valid %p cap %p issued %s "
654a8599bd8SSage Weil 		     "but STALE (gen %u vs %u)\n", &cap->ci->vfs_inode,
655685f9a5dSSage Weil 		     cap, ceph_cap_string(cap->issued), cap->cap_gen, gen);
656a8599bd8SSage Weil 		return 0;
657a8599bd8SSage Weil 	}
658a8599bd8SSage Weil 
659a8599bd8SSage Weil 	return 1;
660a8599bd8SSage Weil }
661a8599bd8SSage Weil 
662a8599bd8SSage Weil /*
663a8599bd8SSage Weil  * Return set of valid cap bits issued to us.  Note that caps time
664a8599bd8SSage Weil  * out, and may be invalidated in bulk if the client session times out
665a8599bd8SSage Weil  * and session->s_cap_gen is bumped.
666a8599bd8SSage Weil  */
667a8599bd8SSage Weil int __ceph_caps_issued(struct ceph_inode_info *ci, int *implemented)
668a8599bd8SSage Weil {
669d9df2783SYan, Zheng 	int have = ci->i_snap_caps;
670a8599bd8SSage Weil 	struct ceph_cap *cap;
671a8599bd8SSage Weil 	struct rb_node *p;
672a8599bd8SSage Weil 
673a8599bd8SSage Weil 	if (implemented)
674a8599bd8SSage Weil 		*implemented = 0;
675a8599bd8SSage Weil 	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
676a8599bd8SSage Weil 		cap = rb_entry(p, struct ceph_cap, ci_node);
677a8599bd8SSage Weil 		if (!__cap_is_valid(cap))
678a8599bd8SSage Weil 			continue;
679a8599bd8SSage Weil 		dout("__ceph_caps_issued %p cap %p issued %s\n",
680a8599bd8SSage Weil 		     &ci->vfs_inode, cap, ceph_cap_string(cap->issued));
681a8599bd8SSage Weil 		have |= cap->issued;
682a8599bd8SSage Weil 		if (implemented)
683a8599bd8SSage Weil 			*implemented |= cap->implemented;
684a8599bd8SSage Weil 	}
685b1530f57SYan, Zheng 	/*
686b1530f57SYan, Zheng 	 * exclude caps issued by non-auth MDS, but are been revoking
687b1530f57SYan, Zheng 	 * by the auth MDS. The non-auth MDS should be revoking/exporting
688b1530f57SYan, Zheng 	 * these caps, but the message is delayed.
689b1530f57SYan, Zheng 	 */
690b1530f57SYan, Zheng 	if (ci->i_auth_cap) {
691b1530f57SYan, Zheng 		cap = ci->i_auth_cap;
692b1530f57SYan, Zheng 		have &= ~cap->implemented | cap->issued;
693b1530f57SYan, Zheng 	}
694a8599bd8SSage Weil 	return have;
695a8599bd8SSage Weil }
696a8599bd8SSage Weil 
697a8599bd8SSage Weil /*
698a8599bd8SSage Weil  * Get cap bits issued by caps other than @ocap
699a8599bd8SSage Weil  */
700a8599bd8SSage Weil int __ceph_caps_issued_other(struct ceph_inode_info *ci, struct ceph_cap *ocap)
701a8599bd8SSage Weil {
702a8599bd8SSage Weil 	int have = ci->i_snap_caps;
703a8599bd8SSage Weil 	struct ceph_cap *cap;
704a8599bd8SSage Weil 	struct rb_node *p;
705a8599bd8SSage Weil 
706a8599bd8SSage Weil 	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
707a8599bd8SSage Weil 		cap = rb_entry(p, struct ceph_cap, ci_node);
708a8599bd8SSage Weil 		if (cap == ocap)
709a8599bd8SSage Weil 			continue;
710a8599bd8SSage Weil 		if (!__cap_is_valid(cap))
711a8599bd8SSage Weil 			continue;
712a8599bd8SSage Weil 		have |= cap->issued;
713a8599bd8SSage Weil 	}
714a8599bd8SSage Weil 	return have;
715a8599bd8SSage Weil }
716a8599bd8SSage Weil 
717a8599bd8SSage Weil /*
718a8599bd8SSage Weil  * Move a cap to the end of the LRU (oldest caps at list head, newest
719a8599bd8SSage Weil  * at list tail).
720a8599bd8SSage Weil  */
721a8599bd8SSage Weil static void __touch_cap(struct ceph_cap *cap)
722a8599bd8SSage Weil {
723a8599bd8SSage Weil 	struct ceph_mds_session *s = cap->session;
724a8599bd8SSage Weil 
7255dacf091SSage Weil 	spin_lock(&s->s_cap_lock);
7267c1332b8SSage Weil 	if (s->s_cap_iterator == NULL) {
727a8599bd8SSage Weil 		dout("__touch_cap %p cap %p mds%d\n", &cap->ci->vfs_inode, cap,
728a8599bd8SSage Weil 		     s->s_mds);
729a8599bd8SSage Weil 		list_move_tail(&cap->session_caps, &s->s_caps);
7305dacf091SSage Weil 	} else {
7315dacf091SSage Weil 		dout("__touch_cap %p cap %p mds%d NOP, iterating over caps\n",
7325dacf091SSage Weil 		     &cap->ci->vfs_inode, cap, s->s_mds);
7335dacf091SSage Weil 	}
734a8599bd8SSage Weil 	spin_unlock(&s->s_cap_lock);
735a8599bd8SSage Weil }
736a8599bd8SSage Weil 
737a8599bd8SSage Weil /*
738a8599bd8SSage Weil  * Check if we hold the given mask.  If so, move the cap(s) to the
739a8599bd8SSage Weil  * front of their respective LRUs.  (This is the preferred way for
740a8599bd8SSage Weil  * callers to check for caps they want.)
741a8599bd8SSage Weil  */
742a8599bd8SSage Weil int __ceph_caps_issued_mask(struct ceph_inode_info *ci, int mask, int touch)
743a8599bd8SSage Weil {
744a8599bd8SSage Weil 	struct ceph_cap *cap;
745a8599bd8SSage Weil 	struct rb_node *p;
746a8599bd8SSage Weil 	int have = ci->i_snap_caps;
747a8599bd8SSage Weil 
748a8599bd8SSage Weil 	if ((have & mask) == mask) {
749a8599bd8SSage Weil 		dout("__ceph_caps_issued_mask %p snap issued %s"
750a8599bd8SSage Weil 		     " (mask %s)\n", &ci->vfs_inode,
751a8599bd8SSage Weil 		     ceph_cap_string(have),
752a8599bd8SSage Weil 		     ceph_cap_string(mask));
753a8599bd8SSage Weil 		return 1;
754a8599bd8SSage Weil 	}
755a8599bd8SSage Weil 
756a8599bd8SSage Weil 	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
757a8599bd8SSage Weil 		cap = rb_entry(p, struct ceph_cap, ci_node);
758a8599bd8SSage Weil 		if (!__cap_is_valid(cap))
759a8599bd8SSage Weil 			continue;
760a8599bd8SSage Weil 		if ((cap->issued & mask) == mask) {
761a8599bd8SSage Weil 			dout("__ceph_caps_issued_mask %p cap %p issued %s"
762a8599bd8SSage Weil 			     " (mask %s)\n", &ci->vfs_inode, cap,
763a8599bd8SSage Weil 			     ceph_cap_string(cap->issued),
764a8599bd8SSage Weil 			     ceph_cap_string(mask));
765a8599bd8SSage Weil 			if (touch)
766a8599bd8SSage Weil 				__touch_cap(cap);
767a8599bd8SSage Weil 			return 1;
768a8599bd8SSage Weil 		}
769a8599bd8SSage Weil 
770a8599bd8SSage Weil 		/* does a combination of caps satisfy mask? */
771a8599bd8SSage Weil 		have |= cap->issued;
772a8599bd8SSage Weil 		if ((have & mask) == mask) {
773a8599bd8SSage Weil 			dout("__ceph_caps_issued_mask %p combo issued %s"
774a8599bd8SSage Weil 			     " (mask %s)\n", &ci->vfs_inode,
775a8599bd8SSage Weil 			     ceph_cap_string(cap->issued),
776a8599bd8SSage Weil 			     ceph_cap_string(mask));
777a8599bd8SSage Weil 			if (touch) {
778a8599bd8SSage Weil 				struct rb_node *q;
779a8599bd8SSage Weil 
78025985edcSLucas De Marchi 				/* touch this + preceding caps */
781a8599bd8SSage Weil 				__touch_cap(cap);
782a8599bd8SSage Weil 				for (q = rb_first(&ci->i_caps); q != p;
783a8599bd8SSage Weil 				     q = rb_next(q)) {
784a8599bd8SSage Weil 					cap = rb_entry(q, struct ceph_cap,
785a8599bd8SSage Weil 						       ci_node);
786a8599bd8SSage Weil 					if (!__cap_is_valid(cap))
787a8599bd8SSage Weil 						continue;
788a8599bd8SSage Weil 					__touch_cap(cap);
789a8599bd8SSage Weil 				}
790a8599bd8SSage Weil 			}
791a8599bd8SSage Weil 			return 1;
792a8599bd8SSage Weil 		}
793a8599bd8SSage Weil 	}
794a8599bd8SSage Weil 
795a8599bd8SSage Weil 	return 0;
796a8599bd8SSage Weil }
797a8599bd8SSage Weil 
798a8599bd8SSage Weil /*
799a8599bd8SSage Weil  * Return true if mask caps are currently being revoked by an MDS.
800a8599bd8SSage Weil  */
8016ee6b953SYan, Zheng int __ceph_caps_revoking_other(struct ceph_inode_info *ci,
8026ee6b953SYan, Zheng 			       struct ceph_cap *ocap, int mask)
8036ee6b953SYan, Zheng {
8046ee6b953SYan, Zheng 	struct ceph_cap *cap;
8056ee6b953SYan, Zheng 	struct rb_node *p;
8066ee6b953SYan, Zheng 
8076ee6b953SYan, Zheng 	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
8086ee6b953SYan, Zheng 		cap = rb_entry(p, struct ceph_cap, ci_node);
8099563f88cSYan, Zheng 		if (cap != ocap &&
8106ee6b953SYan, Zheng 		    (cap->implemented & ~cap->issued & mask))
8116ee6b953SYan, Zheng 			return 1;
8126ee6b953SYan, Zheng 	}
8136ee6b953SYan, Zheng 	return 0;
8146ee6b953SYan, Zheng }
8156ee6b953SYan, Zheng 
816a8599bd8SSage Weil int ceph_caps_revoking(struct ceph_inode_info *ci, int mask)
817a8599bd8SSage Weil {
818a8599bd8SSage Weil 	struct inode *inode = &ci->vfs_inode;
8196ee6b953SYan, Zheng 	int ret;
820a8599bd8SSage Weil 
821be655596SSage Weil 	spin_lock(&ci->i_ceph_lock);
8226ee6b953SYan, Zheng 	ret = __ceph_caps_revoking_other(ci, NULL, mask);
823be655596SSage Weil 	spin_unlock(&ci->i_ceph_lock);
824a8599bd8SSage Weil 	dout("ceph_caps_revoking %p %s = %d\n", inode,
825a8599bd8SSage Weil 	     ceph_cap_string(mask), ret);
826a8599bd8SSage Weil 	return ret;
827a8599bd8SSage Weil }
828a8599bd8SSage Weil 
829a8599bd8SSage Weil int __ceph_caps_used(struct ceph_inode_info *ci)
830a8599bd8SSage Weil {
831a8599bd8SSage Weil 	int used = 0;
832a8599bd8SSage Weil 	if (ci->i_pin_ref)
833a8599bd8SSage Weil 		used |= CEPH_CAP_PIN;
834a8599bd8SSage Weil 	if (ci->i_rd_ref)
835a8599bd8SSage Weil 		used |= CEPH_CAP_FILE_RD;
836a43fb731SSage Weil 	if (ci->i_rdcache_ref || ci->vfs_inode.i_data.nrpages)
837a8599bd8SSage Weil 		used |= CEPH_CAP_FILE_CACHE;
838a8599bd8SSage Weil 	if (ci->i_wr_ref)
839a8599bd8SSage Weil 		used |= CEPH_CAP_FILE_WR;
840d3d0720dSHenry C Chang 	if (ci->i_wb_ref || ci->i_wrbuffer_ref)
841a8599bd8SSage Weil 		used |= CEPH_CAP_FILE_BUFFER;
842a8599bd8SSage Weil 	return used;
843a8599bd8SSage Weil }
844a8599bd8SSage Weil 
845a8599bd8SSage Weil /*
846a8599bd8SSage Weil  * wanted, by virtue of open file modes
847a8599bd8SSage Weil  */
848a8599bd8SSage Weil int __ceph_caps_file_wanted(struct ceph_inode_info *ci)
849a8599bd8SSage Weil {
850a8599bd8SSage Weil 	int want = 0;
851a8599bd8SSage Weil 	int mode;
85233caad32SSage Weil 	for (mode = 0; mode < CEPH_FILE_MODE_NUM; mode++)
853a8599bd8SSage Weil 		if (ci->i_nr_by_mode[mode])
854a8599bd8SSage Weil 			want |= ceph_caps_for_mode(mode);
855a8599bd8SSage Weil 	return want;
856a8599bd8SSage Weil }
857a8599bd8SSage Weil 
858a8599bd8SSage Weil /*
859a8599bd8SSage Weil  * Return caps we have registered with the MDS(s) as 'wanted'.
860a8599bd8SSage Weil  */
861a8599bd8SSage Weil int __ceph_caps_mds_wanted(struct ceph_inode_info *ci)
862a8599bd8SSage Weil {
863a8599bd8SSage Weil 	struct ceph_cap *cap;
864a8599bd8SSage Weil 	struct rb_node *p;
865a8599bd8SSage Weil 	int mds_wanted = 0;
866a8599bd8SSage Weil 
867a8599bd8SSage Weil 	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
868a8599bd8SSage Weil 		cap = rb_entry(p, struct ceph_cap, ci_node);
869a8599bd8SSage Weil 		if (!__cap_is_valid(cap))
870a8599bd8SSage Weil 			continue;
871a2550604SYan, Zheng 		if (cap == ci->i_auth_cap)
872a8599bd8SSage Weil 			mds_wanted |= cap->mds_wanted;
873a2550604SYan, Zheng 		else
874a2550604SYan, Zheng 			mds_wanted |= (cap->mds_wanted & ~CEPH_CAP_ANY_FILE_WR);
875a8599bd8SSage Weil 	}
876a8599bd8SSage Weil 	return mds_wanted;
877a8599bd8SSage Weil }
878a8599bd8SSage Weil 
879a8599bd8SSage Weil /*
880be655596SSage Weil  * called under i_ceph_lock
881a8599bd8SSage Weil  */
882a8599bd8SSage Weil static int __ceph_is_any_caps(struct ceph_inode_info *ci)
883a8599bd8SSage Weil {
884d9df2783SYan, Zheng 	return !RB_EMPTY_ROOT(&ci->i_caps);
885a8599bd8SSage Weil }
886a8599bd8SSage Weil 
8879215aeeaSYan, Zheng int ceph_is_any_caps(struct inode *inode)
8889215aeeaSYan, Zheng {
8899215aeeaSYan, Zheng 	struct ceph_inode_info *ci = ceph_inode(inode);
8909215aeeaSYan, Zheng 	int ret;
8919215aeeaSYan, Zheng 
8929215aeeaSYan, Zheng 	spin_lock(&ci->i_ceph_lock);
8939215aeeaSYan, Zheng 	ret = __ceph_is_any_caps(ci);
8949215aeeaSYan, Zheng 	spin_unlock(&ci->i_ceph_lock);
8959215aeeaSYan, Zheng 
8969215aeeaSYan, Zheng 	return ret;
8979215aeeaSYan, Zheng }
8989215aeeaSYan, Zheng 
899a8599bd8SSage Weil /*
900f818a736SSage Weil  * Remove a cap.  Take steps to deal with a racing iterate_session_caps.
901f818a736SSage Weil  *
902be655596SSage Weil  * caller should hold i_ceph_lock.
903a6369741SSage Weil  * caller will not hold session s_mutex if called from destroy_inode.
904a8599bd8SSage Weil  */
905a096b09aSYan, Zheng void __ceph_remove_cap(struct ceph_cap *cap, bool queue_release)
906a8599bd8SSage Weil {
907a8599bd8SSage Weil 	struct ceph_mds_session *session = cap->session;
908a8599bd8SSage Weil 	struct ceph_inode_info *ci = cap->ci;
909640ef79dSCheng Renquan 	struct ceph_mds_client *mdsc =
9103d14c5d2SYehuda Sadeh 		ceph_sb_to_client(ci->vfs_inode.i_sb)->mdsc;
911f818a736SSage Weil 	int removed = 0;
912a8599bd8SSage Weil 
913a8599bd8SSage Weil 	dout("__ceph_remove_cap %p from %p\n", cap, &ci->vfs_inode);
914a8599bd8SSage Weil 
9157c1332b8SSage Weil 	/* remove from session list */
9167c1332b8SSage Weil 	spin_lock(&session->s_cap_lock);
91799a9c273SYan, Zheng 	/*
91899a9c273SYan, Zheng 	 * s_cap_reconnect is protected by s_cap_lock. no one changes
91999a9c273SYan, Zheng 	 * s_cap_gen while session is in the reconnect state.
92099a9c273SYan, Zheng 	 */
92199a9c273SYan, Zheng 	if (queue_release &&
92299a9c273SYan, Zheng 	    (!session->s_cap_reconnect ||
92399a9c273SYan, Zheng 	     cap->cap_gen == session->s_cap_gen))
924a096b09aSYan, Zheng 		__queue_cap_release(session, ci->i_vino.ino, cap->cap_id,
925a096b09aSYan, Zheng 				    cap->mseq, cap->issue_seq);
926a096b09aSYan, Zheng 
9277c1332b8SSage Weil 	if (session->s_cap_iterator == cap) {
9287c1332b8SSage Weil 		/* not yet, we are iterating over this very cap */
9297c1332b8SSage Weil 		dout("__ceph_remove_cap  delaying %p removal from session %p\n",
9307c1332b8SSage Weil 		     cap, cap->session);
9317c1332b8SSage Weil 	} else {
9327c1332b8SSage Weil 		list_del_init(&cap->session_caps);
9337c1332b8SSage Weil 		session->s_nr_caps--;
9347c1332b8SSage Weil 		cap->session = NULL;
935f818a736SSage Weil 		removed = 1;
9367c1332b8SSage Weil 	}
937f818a736SSage Weil 	/* protect backpointer with s_cap_lock: see iterate_session_caps */
938f818a736SSage Weil 	cap->ci = NULL;
9397c1332b8SSage Weil 	spin_unlock(&session->s_cap_lock);
9407c1332b8SSage Weil 
941f818a736SSage Weil 	/* remove from inode list */
942f818a736SSage Weil 	rb_erase(&cap->ci_node, &ci->i_caps);
943f818a736SSage Weil 	if (ci->i_auth_cap == cap)
944f818a736SSage Weil 		ci->i_auth_cap = NULL;
945f818a736SSage Weil 
946f818a736SSage Weil 	if (removed)
94737151668SYehuda Sadeh 		ceph_put_cap(mdsc, cap);
948a8599bd8SSage Weil 
949a8599bd8SSage Weil 	if (!__ceph_is_any_caps(ci) && ci->i_snap_realm) {
950a8599bd8SSage Weil 		struct ceph_snap_realm *realm = ci->i_snap_realm;
951a8599bd8SSage Weil 		spin_lock(&realm->inodes_with_caps_lock);
952a8599bd8SSage Weil 		list_del_init(&ci->i_snap_realm_item);
953a8599bd8SSage Weil 		ci->i_snap_realm_counter++;
954a8599bd8SSage Weil 		ci->i_snap_realm = NULL;
955a8599bd8SSage Weil 		spin_unlock(&realm->inodes_with_caps_lock);
956a8599bd8SSage Weil 		ceph_put_snap_realm(mdsc, realm);
957a8599bd8SSage Weil 	}
958a8599bd8SSage Weil 	if (!__ceph_is_any_real_caps(ci))
959a8599bd8SSage Weil 		__cap_delay_cancel(mdsc, ci);
960a8599bd8SSage Weil }
961a8599bd8SSage Weil 
962a8599bd8SSage Weil /*
963a8599bd8SSage Weil  * Build and send a cap message to the given MDS.
964a8599bd8SSage Weil  *
965a8599bd8SSage Weil  * Caller should be holding s_mutex.
966a8599bd8SSage Weil  */
967a8599bd8SSage Weil static int send_cap_msg(struct ceph_mds_session *session,
968a8599bd8SSage Weil 			u64 ino, u64 cid, int op,
969a8599bd8SSage Weil 			int caps, int wanted, int dirty,
970a8599bd8SSage Weil 			u32 seq, u64 flush_tid, u32 issue_seq, u32 mseq,
971a8599bd8SSage Weil 			u64 size, u64 max_size,
972a8599bd8SSage Weil 			struct timespec *mtime, struct timespec *atime,
973a8599bd8SSage Weil 			u64 time_warp_seq,
97405cb11c1SEric W. Biederman 			kuid_t uid, kgid_t gid, umode_t mode,
975a8599bd8SSage Weil 			u64 xattr_version,
976a8599bd8SSage Weil 			struct ceph_buffer *xattrs_buf,
977e20d258dSYan, Zheng 			u64 follows, bool inline_data)
978a8599bd8SSage Weil {
979a8599bd8SSage Weil 	struct ceph_mds_caps *fc;
980a8599bd8SSage Weil 	struct ceph_msg *msg;
981e20d258dSYan, Zheng 	void *p;
982e20d258dSYan, Zheng 	size_t extra_len;
983a8599bd8SSage Weil 
984a8599bd8SSage Weil 	dout("send_cap_msg %s %llx %llx caps %s wanted %s dirty %s"
985a8599bd8SSage Weil 	     " seq %u/%u mseq %u follows %lld size %llu/%llu"
986a8599bd8SSage Weil 	     " xattr_ver %llu xattr_len %d\n", ceph_cap_op_name(op),
987a8599bd8SSage Weil 	     cid, ino, ceph_cap_string(caps), ceph_cap_string(wanted),
988a8599bd8SSage Weil 	     ceph_cap_string(dirty),
989a8599bd8SSage Weil 	     seq, issue_seq, mseq, follows, size, max_size,
990a8599bd8SSage Weil 	     xattr_version, xattrs_buf ? (int)xattrs_buf->vec.iov_len : 0);
991a8599bd8SSage Weil 
992e20d258dSYan, Zheng 	/* flock buffer size + inline version + inline data size */
993e20d258dSYan, Zheng 	extra_len = 4 + 8 + 4;
994e20d258dSYan, Zheng 	msg = ceph_msg_new(CEPH_MSG_CLIENT_CAPS, sizeof(*fc) + extra_len,
995e20d258dSYan, Zheng 			   GFP_NOFS, false);
996a79832f2SSage Weil 	if (!msg)
997a79832f2SSage Weil 		return -ENOMEM;
998a8599bd8SSage Weil 
9996df058c0SSage Weil 	msg->hdr.tid = cpu_to_le64(flush_tid);
1000a8599bd8SSage Weil 
10016df058c0SSage Weil 	fc = msg->front.iov_base;
1002a8599bd8SSage Weil 	memset(fc, 0, sizeof(*fc));
1003a8599bd8SSage Weil 
1004a8599bd8SSage Weil 	fc->cap_id = cpu_to_le64(cid);
1005a8599bd8SSage Weil 	fc->op = cpu_to_le32(op);
1006a8599bd8SSage Weil 	fc->seq = cpu_to_le32(seq);
1007a8599bd8SSage Weil 	fc->issue_seq = cpu_to_le32(issue_seq);
1008a8599bd8SSage Weil 	fc->migrate_seq = cpu_to_le32(mseq);
1009a8599bd8SSage Weil 	fc->caps = cpu_to_le32(caps);
1010a8599bd8SSage Weil 	fc->wanted = cpu_to_le32(wanted);
1011a8599bd8SSage Weil 	fc->dirty = cpu_to_le32(dirty);
1012a8599bd8SSage Weil 	fc->ino = cpu_to_le64(ino);
1013a8599bd8SSage Weil 	fc->snap_follows = cpu_to_le64(follows);
1014a8599bd8SSage Weil 
1015a8599bd8SSage Weil 	fc->size = cpu_to_le64(size);
1016a8599bd8SSage Weil 	fc->max_size = cpu_to_le64(max_size);
1017a8599bd8SSage Weil 	if (mtime)
1018a8599bd8SSage Weil 		ceph_encode_timespec(&fc->mtime, mtime);
1019a8599bd8SSage Weil 	if (atime)
1020a8599bd8SSage Weil 		ceph_encode_timespec(&fc->atime, atime);
1021a8599bd8SSage Weil 	fc->time_warp_seq = cpu_to_le32(time_warp_seq);
1022a8599bd8SSage Weil 
102305cb11c1SEric W. Biederman 	fc->uid = cpu_to_le32(from_kuid(&init_user_ns, uid));
102405cb11c1SEric W. Biederman 	fc->gid = cpu_to_le32(from_kgid(&init_user_ns, gid));
1025a8599bd8SSage Weil 	fc->mode = cpu_to_le32(mode);
1026a8599bd8SSage Weil 
1027e20d258dSYan, Zheng 	p = fc + 1;
1028e20d258dSYan, Zheng 	/* flock buffer size */
1029e20d258dSYan, Zheng 	ceph_encode_32(&p, 0);
1030e20d258dSYan, Zheng 	/* inline version */
1031e20d258dSYan, Zheng 	ceph_encode_64(&p, inline_data ? 0 : CEPH_INLINE_NONE);
1032e20d258dSYan, Zheng 	/* inline data size */
1033e20d258dSYan, Zheng 	ceph_encode_32(&p, 0);
1034e20d258dSYan, Zheng 
1035a8599bd8SSage Weil 	fc->xattr_version = cpu_to_le64(xattr_version);
1036a8599bd8SSage Weil 	if (xattrs_buf) {
1037a8599bd8SSage Weil 		msg->middle = ceph_buffer_get(xattrs_buf);
1038a8599bd8SSage Weil 		fc->xattr_len = cpu_to_le32(xattrs_buf->vec.iov_len);
1039a8599bd8SSage Weil 		msg->hdr.middle_len = cpu_to_le32(xattrs_buf->vec.iov_len);
1040a8599bd8SSage Weil 	}
1041a8599bd8SSage Weil 
1042a8599bd8SSage Weil 	ceph_con_send(&session->s_con, msg);
1043a8599bd8SSage Weil 	return 0;
1044a8599bd8SSage Weil }
1045a8599bd8SSage Weil 
1046d40ee0dcSYan, Zheng void __queue_cap_release(struct ceph_mds_session *session,
10473d7ded4dSSage Weil 			 u64 ino, u64 cap_id, u32 migrate_seq,
10483d7ded4dSSage Weil 			 u32 issue_seq)
10493d7ded4dSSage Weil {
10503d7ded4dSSage Weil 	struct ceph_msg *msg;
10513d7ded4dSSage Weil 	struct ceph_mds_cap_release *head;
10523d7ded4dSSage Weil 	struct ceph_mds_cap_item *item;
10533d7ded4dSSage Weil 
10543d7ded4dSSage Weil 	BUG_ON(!session->s_num_cap_releases);
10553d7ded4dSSage Weil 	msg = list_first_entry(&session->s_cap_releases,
10563d7ded4dSSage Weil 			       struct ceph_msg, list_head);
10573d7ded4dSSage Weil 
10583d7ded4dSSage Weil 	dout(" adding %llx release to mds%d msg %p (%d left)\n",
10593d7ded4dSSage Weil 	     ino, session->s_mds, msg, session->s_num_cap_releases);
10603d7ded4dSSage Weil 
10613d7ded4dSSage Weil 	BUG_ON(msg->front.iov_len + sizeof(*item) > PAGE_CACHE_SIZE);
10623d7ded4dSSage Weil 	head = msg->front.iov_base;
1063b905a7f8SWei Yongjun 	le32_add_cpu(&head->num, 1);
10643d7ded4dSSage Weil 	item = msg->front.iov_base + msg->front.iov_len;
10653d7ded4dSSage Weil 	item->ino = cpu_to_le64(ino);
10663d7ded4dSSage Weil 	item->cap_id = cpu_to_le64(cap_id);
10673d7ded4dSSage Weil 	item->migrate_seq = cpu_to_le32(migrate_seq);
10683d7ded4dSSage Weil 	item->seq = cpu_to_le32(issue_seq);
10693d7ded4dSSage Weil 
10703d7ded4dSSage Weil 	session->s_num_cap_releases--;
10713d7ded4dSSage Weil 
10723d7ded4dSSage Weil 	msg->front.iov_len += sizeof(*item);
10733d7ded4dSSage Weil 	if (le32_to_cpu(head->num) == CEPH_CAPS_PER_RELEASE) {
10743d7ded4dSSage Weil 		dout(" release msg %p full\n", msg);
10753d7ded4dSSage Weil 		list_move_tail(&msg->list_head, &session->s_cap_releases_done);
10763d7ded4dSSage Weil 	} else {
10773d7ded4dSSage Weil 		dout(" release msg %p at %d/%d (%d)\n", msg,
10783d7ded4dSSage Weil 		     (int)le32_to_cpu(head->num),
10793d7ded4dSSage Weil 		     (int)CEPH_CAPS_PER_RELEASE,
10803d7ded4dSSage Weil 		     (int)msg->front.iov_len);
10813d7ded4dSSage Weil 	}
10823d7ded4dSSage Weil }
10833d7ded4dSSage Weil 
1084a8599bd8SSage Weil /*
1085a6369741SSage Weil  * Queue cap releases when an inode is dropped from our cache.  Since
1086be655596SSage Weil  * inode is about to be destroyed, there is no need for i_ceph_lock.
1087a8599bd8SSage Weil  */
1088a8599bd8SSage Weil void ceph_queue_caps_release(struct inode *inode)
1089a8599bd8SSage Weil {
1090a8599bd8SSage Weil 	struct ceph_inode_info *ci = ceph_inode(inode);
1091a8599bd8SSage Weil 	struct rb_node *p;
1092a8599bd8SSage Weil 
1093a8599bd8SSage Weil 	p = rb_first(&ci->i_caps);
1094a8599bd8SSage Weil 	while (p) {
1095a8599bd8SSage Weil 		struct ceph_cap *cap = rb_entry(p, struct ceph_cap, ci_node);
1096a8599bd8SSage Weil 		p = rb_next(p);
1097a096b09aSYan, Zheng 		__ceph_remove_cap(cap, true);
1098a8599bd8SSage Weil 	}
1099a8599bd8SSage Weil }
1100a8599bd8SSage Weil 
1101a8599bd8SSage Weil /*
1102a8599bd8SSage Weil  * Send a cap msg on the given inode.  Update our caps state, then
1103be655596SSage Weil  * drop i_ceph_lock and send the message.
1104a8599bd8SSage Weil  *
1105a8599bd8SSage Weil  * Make note of max_size reported/requested from mds, revoked caps
1106a8599bd8SSage Weil  * that have now been implemented.
1107a8599bd8SSage Weil  *
1108a8599bd8SSage Weil  * Make half-hearted attempt ot to invalidate page cache if we are
1109a8599bd8SSage Weil  * dropping RDCACHE.  Note that this will leave behind locked pages
1110a8599bd8SSage Weil  * that we'll then need to deal with elsewhere.
1111a8599bd8SSage Weil  *
1112a8599bd8SSage Weil  * Return non-zero if delayed release, or we experienced an error
1113a8599bd8SSage Weil  * such that the caller should requeue + retry later.
1114a8599bd8SSage Weil  *
1115be655596SSage Weil  * called with i_ceph_lock, then drops it.
1116a8599bd8SSage Weil  * caller should hold snap_rwsem (read), s_mutex.
1117a8599bd8SSage Weil  */
1118a8599bd8SSage Weil static int __send_cap(struct ceph_mds_client *mdsc, struct ceph_cap *cap,
1119a8599bd8SSage Weil 		      int op, int used, int want, int retain, int flushing,
1120a8599bd8SSage Weil 		      unsigned *pflush_tid)
1121be655596SSage Weil 	__releases(cap->ci->i_ceph_lock)
1122a8599bd8SSage Weil {
1123a8599bd8SSage Weil 	struct ceph_inode_info *ci = cap->ci;
1124a8599bd8SSage Weil 	struct inode *inode = &ci->vfs_inode;
1125a8599bd8SSage Weil 	u64 cap_id = cap->cap_id;
112668c28323SSage Weil 	int held, revoking, dropping, keep;
1127a8599bd8SSage Weil 	u64 seq, issue_seq, mseq, time_warp_seq, follows;
1128a8599bd8SSage Weil 	u64 size, max_size;
1129a8599bd8SSage Weil 	struct timespec mtime, atime;
1130a8599bd8SSage Weil 	int wake = 0;
11315706b27dSAl Viro 	umode_t mode;
113205cb11c1SEric W. Biederman 	kuid_t uid;
113305cb11c1SEric W. Biederman 	kgid_t gid;
1134a8599bd8SSage Weil 	struct ceph_mds_session *session;
1135a8599bd8SSage Weil 	u64 xattr_version = 0;
1136082afec9SSage Weil 	struct ceph_buffer *xattr_blob = NULL;
1137a8599bd8SSage Weil 	int delayed = 0;
1138a8599bd8SSage Weil 	u64 flush_tid = 0;
1139a8599bd8SSage Weil 	int i;
1140a8599bd8SSage Weil 	int ret;
1141e20d258dSYan, Zheng 	bool inline_data;
1142a8599bd8SSage Weil 
114368c28323SSage Weil 	held = cap->issued | cap->implemented;
114468c28323SSage Weil 	revoking = cap->implemented & ~cap->issued;
114568c28323SSage Weil 	retain &= ~revoking;
114668c28323SSage Weil 	dropping = cap->issued & ~retain;
114768c28323SSage Weil 
1148a8599bd8SSage Weil 	dout("__send_cap %p cap %p session %p %s -> %s (revoking %s)\n",
1149a8599bd8SSage Weil 	     inode, cap, cap->session,
1150a8599bd8SSage Weil 	     ceph_cap_string(held), ceph_cap_string(held & retain),
1151a8599bd8SSage Weil 	     ceph_cap_string(revoking));
1152a8599bd8SSage Weil 	BUG_ON((retain & CEPH_CAP_PIN) == 0);
1153a8599bd8SSage Weil 
1154a8599bd8SSage Weil 	session = cap->session;
1155a8599bd8SSage Weil 
1156a8599bd8SSage Weil 	/* don't release wanted unless we've waited a bit. */
1157a8599bd8SSage Weil 	if ((ci->i_ceph_flags & CEPH_I_NODELAY) == 0 &&
1158a8599bd8SSage Weil 	    time_before(jiffies, ci->i_hold_caps_min)) {
1159a8599bd8SSage Weil 		dout(" delaying issued %s -> %s, wanted %s -> %s on send\n",
1160a8599bd8SSage Weil 		     ceph_cap_string(cap->issued),
1161a8599bd8SSage Weil 		     ceph_cap_string(cap->issued & retain),
1162a8599bd8SSage Weil 		     ceph_cap_string(cap->mds_wanted),
1163a8599bd8SSage Weil 		     ceph_cap_string(want));
1164a8599bd8SSage Weil 		want |= cap->mds_wanted;
1165a8599bd8SSage Weil 		retain |= cap->issued;
1166a8599bd8SSage Weil 		delayed = 1;
1167a8599bd8SSage Weil 	}
1168a8599bd8SSage Weil 	ci->i_ceph_flags &= ~(CEPH_I_NODELAY | CEPH_I_FLUSH);
1169a8599bd8SSage Weil 
1170a8599bd8SSage Weil 	cap->issued &= retain;  /* drop bits we don't want */
1171a8599bd8SSage Weil 	if (cap->implemented & ~cap->issued) {
1172a8599bd8SSage Weil 		/*
1173a8599bd8SSage Weil 		 * Wake up any waiters on wanted -> needed transition.
1174a8599bd8SSage Weil 		 * This is due to the weird transition from buffered
1175a8599bd8SSage Weil 		 * to sync IO... we need to flush dirty pages _before_
1176a8599bd8SSage Weil 		 * allowing sync writes to avoid reordering.
1177a8599bd8SSage Weil 		 */
1178a8599bd8SSage Weil 		wake = 1;
1179a8599bd8SSage Weil 	}
1180a8599bd8SSage Weil 	cap->implemented &= cap->issued | used;
1181a8599bd8SSage Weil 	cap->mds_wanted = want;
1182a8599bd8SSage Weil 
1183a8599bd8SSage Weil 	if (flushing) {
1184a8599bd8SSage Weil 		/*
1185a8599bd8SSage Weil 		 * assign a tid for flush operations so we can avoid
1186a8599bd8SSage Weil 		 * flush1 -> dirty1 -> flush2 -> flushack1 -> mark
1187a8599bd8SSage Weil 		 * clean type races.  track latest tid for every bit
1188a8599bd8SSage Weil 		 * so we can handle flush AxFw, flush Fw, and have the
1189a8599bd8SSage Weil 		 * first ack clean Ax.
1190a8599bd8SSage Weil 		 */
1191a8599bd8SSage Weil 		flush_tid = ++ci->i_cap_flush_last_tid;
1192a8599bd8SSage Weil 		if (pflush_tid)
1193a8599bd8SSage Weil 			*pflush_tid = flush_tid;
1194a8599bd8SSage Weil 		dout(" cap_flush_tid %d\n", (int)flush_tid);
1195a8599bd8SSage Weil 		for (i = 0; i < CEPH_CAP_BITS; i++)
1196a8599bd8SSage Weil 			if (flushing & (1 << i))
1197a8599bd8SSage Weil 				ci->i_cap_flush_tid[i] = flush_tid;
11987d8cb26dSSage Weil 
11997d8cb26dSSage Weil 		follows = ci->i_head_snapc->seq;
12007d8cb26dSSage Weil 	} else {
12017d8cb26dSSage Weil 		follows = 0;
1202a8599bd8SSage Weil 	}
1203a8599bd8SSage Weil 
1204a8599bd8SSage Weil 	keep = cap->implemented;
1205a8599bd8SSage Weil 	seq = cap->seq;
1206a8599bd8SSage Weil 	issue_seq = cap->issue_seq;
1207a8599bd8SSage Weil 	mseq = cap->mseq;
1208a8599bd8SSage Weil 	size = inode->i_size;
1209a8599bd8SSage Weil 	ci->i_reported_size = size;
1210a8599bd8SSage Weil 	max_size = ci->i_wanted_max_size;
1211a8599bd8SSage Weil 	ci->i_requested_max_size = max_size;
1212a8599bd8SSage Weil 	mtime = inode->i_mtime;
1213a8599bd8SSage Weil 	atime = inode->i_atime;
1214a8599bd8SSage Weil 	time_warp_seq = ci->i_time_warp_seq;
1215a8599bd8SSage Weil 	uid = inode->i_uid;
1216a8599bd8SSage Weil 	gid = inode->i_gid;
1217a8599bd8SSage Weil 	mode = inode->i_mode;
1218a8599bd8SSage Weil 
1219082afec9SSage Weil 	if (flushing & CEPH_CAP_XATTR_EXCL) {
1220a8599bd8SSage Weil 		__ceph_build_xattrs_blob(ci);
1221082afec9SSage Weil 		xattr_blob = ci->i_xattrs.blob;
1222082afec9SSage Weil 		xattr_version = ci->i_xattrs.version;
1223a8599bd8SSage Weil 	}
1224a8599bd8SSage Weil 
1225e20d258dSYan, Zheng 	inline_data = ci->i_inline_version != CEPH_INLINE_NONE;
1226e20d258dSYan, Zheng 
1227be655596SSage Weil 	spin_unlock(&ci->i_ceph_lock);
1228a8599bd8SSage Weil 
1229a8599bd8SSage Weil 	ret = send_cap_msg(session, ceph_vino(inode).ino, cap_id,
1230a8599bd8SSage Weil 		op, keep, want, flushing, seq, flush_tid, issue_seq, mseq,
1231a8599bd8SSage Weil 		size, max_size, &mtime, &atime, time_warp_seq,
1232082afec9SSage Weil 		uid, gid, mode, xattr_version, xattr_blob,
1233e20d258dSYan, Zheng 		follows, inline_data);
1234a8599bd8SSage Weil 	if (ret < 0) {
1235a8599bd8SSage Weil 		dout("error sending cap msg, must requeue %p\n", inode);
1236a8599bd8SSage Weil 		delayed = 1;
1237a8599bd8SSage Weil 	}
1238a8599bd8SSage Weil 
1239a8599bd8SSage Weil 	if (wake)
124003066f23SYehuda Sadeh 		wake_up_all(&ci->i_cap_wq);
1241a8599bd8SSage Weil 
1242a8599bd8SSage Weil 	return delayed;
1243a8599bd8SSage Weil }
1244a8599bd8SSage Weil 
1245a8599bd8SSage Weil /*
1246a8599bd8SSage Weil  * When a snapshot is taken, clients accumulate dirty metadata on
1247a8599bd8SSage Weil  * inodes with capabilities in ceph_cap_snaps to describe the file
1248a8599bd8SSage Weil  * state at the time the snapshot was taken.  This must be flushed
1249a8599bd8SSage Weil  * asynchronously back to the MDS once sync writes complete and dirty
1250a8599bd8SSage Weil  * data is written out.
1251a8599bd8SSage Weil  *
1252e835124cSSage Weil  * Unless @again is true, skip cap_snaps that were already sent to
1253e835124cSSage Weil  * the MDS (i.e., during this session).
1254e835124cSSage Weil  *
1255be655596SSage Weil  * Called under i_ceph_lock.  Takes s_mutex as needed.
1256a8599bd8SSage Weil  */
1257a8599bd8SSage Weil void __ceph_flush_snaps(struct ceph_inode_info *ci,
1258e835124cSSage Weil 			struct ceph_mds_session **psession,
1259e835124cSSage Weil 			int again)
1260be655596SSage Weil 		__releases(ci->i_ceph_lock)
1261be655596SSage Weil 		__acquires(ci->i_ceph_lock)
1262a8599bd8SSage Weil {
1263a8599bd8SSage Weil 	struct inode *inode = &ci->vfs_inode;
1264a8599bd8SSage Weil 	int mds;
1265a8599bd8SSage Weil 	struct ceph_cap_snap *capsnap;
1266a8599bd8SSage Weil 	u32 mseq;
12673d14c5d2SYehuda Sadeh 	struct ceph_mds_client *mdsc = ceph_inode_to_client(inode)->mdsc;
1268a8599bd8SSage Weil 	struct ceph_mds_session *session = NULL; /* if session != NULL, we hold
1269a8599bd8SSage Weil 						    session->s_mutex */
1270a8599bd8SSage Weil 	u64 next_follows = 0;  /* keep track of how far we've gotten through the
1271a8599bd8SSage Weil 			     i_cap_snaps list, and skip these entries next time
1272a8599bd8SSage Weil 			     around to avoid an infinite loop */
1273a8599bd8SSage Weil 
1274a8599bd8SSage Weil 	if (psession)
1275a8599bd8SSage Weil 		session = *psession;
1276a8599bd8SSage Weil 
1277a8599bd8SSage Weil 	dout("__flush_snaps %p\n", inode);
1278a8599bd8SSage Weil retry:
1279a8599bd8SSage Weil 	list_for_each_entry(capsnap, &ci->i_cap_snaps, ci_item) {
1280a8599bd8SSage Weil 		/* avoid an infiniute loop after retry */
1281a8599bd8SSage Weil 		if (capsnap->follows < next_follows)
1282a8599bd8SSage Weil 			continue;
1283a8599bd8SSage Weil 		/*
1284a8599bd8SSage Weil 		 * we need to wait for sync writes to complete and for dirty
1285a8599bd8SSage Weil 		 * pages to be written out.
1286a8599bd8SSage Weil 		 */
1287a8599bd8SSage Weil 		if (capsnap->dirty_pages || capsnap->writing)
1288cfc0bf66SSage Weil 			break;
1289a8599bd8SSage Weil 
1290819ccbfaSSage Weil 		/*
1291819ccbfaSSage Weil 		 * if cap writeback already occurred, we should have dropped
1292819ccbfaSSage Weil 		 * the capsnap in ceph_put_wrbuffer_cap_refs.
1293819ccbfaSSage Weil 		 */
1294819ccbfaSSage Weil 		BUG_ON(capsnap->dirty == 0);
1295819ccbfaSSage Weil 
1296a8599bd8SSage Weil 		/* pick mds, take s_mutex */
1297ca81f3f6SSage Weil 		if (ci->i_auth_cap == NULL) {
1298ca81f3f6SSage Weil 			dout("no auth cap (migrating?), doing nothing\n");
1299ca81f3f6SSage Weil 			goto out;
1300ca81f3f6SSage Weil 		}
1301e835124cSSage Weil 
1302e835124cSSage Weil 		/* only flush each capsnap once */
1303e835124cSSage Weil 		if (!again && !list_empty(&capsnap->flushing_item)) {
1304e835124cSSage Weil 			dout("already flushed %p, skipping\n", capsnap);
1305e835124cSSage Weil 			continue;
1306e835124cSSage Weil 		}
1307e835124cSSage Weil 
1308ca81f3f6SSage Weil 		mds = ci->i_auth_cap->session->s_mds;
1309ca81f3f6SSage Weil 		mseq = ci->i_auth_cap->mseq;
1310ca81f3f6SSage Weil 
1311a8599bd8SSage Weil 		if (session && session->s_mds != mds) {
1312a8599bd8SSage Weil 			dout("oops, wrong session %p mutex\n", session);
1313a8599bd8SSage Weil 			mutex_unlock(&session->s_mutex);
1314a8599bd8SSage Weil 			ceph_put_mds_session(session);
1315a8599bd8SSage Weil 			session = NULL;
1316a8599bd8SSage Weil 		}
1317a8599bd8SSage Weil 		if (!session) {
1318be655596SSage Weil 			spin_unlock(&ci->i_ceph_lock);
1319a8599bd8SSage Weil 			mutex_lock(&mdsc->mutex);
1320a8599bd8SSage Weil 			session = __ceph_lookup_mds_session(mdsc, mds);
1321a8599bd8SSage Weil 			mutex_unlock(&mdsc->mutex);
1322a8599bd8SSage Weil 			if (session) {
1323a8599bd8SSage Weil 				dout("inverting session/ino locks on %p\n",
1324a8599bd8SSage Weil 				     session);
1325a8599bd8SSage Weil 				mutex_lock(&session->s_mutex);
1326a8599bd8SSage Weil 			}
1327a8599bd8SSage Weil 			/*
1328a8599bd8SSage Weil 			 * if session == NULL, we raced against a cap
1329ca81f3f6SSage Weil 			 * deletion or migration.  retry, and we'll
1330ca81f3f6SSage Weil 			 * get a better @mds value next time.
1331a8599bd8SSage Weil 			 */
1332be655596SSage Weil 			spin_lock(&ci->i_ceph_lock);
1333a8599bd8SSage Weil 			goto retry;
1334a8599bd8SSage Weil 		}
1335a8599bd8SSage Weil 
1336a8599bd8SSage Weil 		capsnap->flush_tid = ++ci->i_cap_flush_last_tid;
1337a8599bd8SSage Weil 		atomic_inc(&capsnap->nref);
1338a8599bd8SSage Weil 		if (!list_empty(&capsnap->flushing_item))
1339a8599bd8SSage Weil 			list_del_init(&capsnap->flushing_item);
1340a8599bd8SSage Weil 		list_add_tail(&capsnap->flushing_item,
1341a8599bd8SSage Weil 			      &session->s_cap_snaps_flushing);
1342be655596SSage Weil 		spin_unlock(&ci->i_ceph_lock);
1343a8599bd8SSage Weil 
1344cfc0bf66SSage Weil 		dout("flush_snaps %p cap_snap %p follows %lld tid %llu\n",
1345cfc0bf66SSage Weil 		     inode, capsnap, capsnap->follows, capsnap->flush_tid);
1346a8599bd8SSage Weil 		send_cap_msg(session, ceph_vino(inode).ino, 0,
1347a8599bd8SSage Weil 			     CEPH_CAP_OP_FLUSHSNAP, capsnap->issued, 0,
1348a8599bd8SSage Weil 			     capsnap->dirty, 0, capsnap->flush_tid, 0, mseq,
1349a8599bd8SSage Weil 			     capsnap->size, 0,
1350a8599bd8SSage Weil 			     &capsnap->mtime, &capsnap->atime,
1351a8599bd8SSage Weil 			     capsnap->time_warp_seq,
1352a8599bd8SSage Weil 			     capsnap->uid, capsnap->gid, capsnap->mode,
13534a625be4SSage Weil 			     capsnap->xattr_version, capsnap->xattr_blob,
1354e20d258dSYan, Zheng 			     capsnap->follows, capsnap->inline_data);
1355a8599bd8SSage Weil 
1356a8599bd8SSage Weil 		next_follows = capsnap->follows + 1;
1357a8599bd8SSage Weil 		ceph_put_cap_snap(capsnap);
1358a8599bd8SSage Weil 
1359be655596SSage Weil 		spin_lock(&ci->i_ceph_lock);
1360a8599bd8SSage Weil 		goto retry;
1361a8599bd8SSage Weil 	}
1362a8599bd8SSage Weil 
1363a8599bd8SSage Weil 	/* we flushed them all; remove this inode from the queue */
1364a8599bd8SSage Weil 	spin_lock(&mdsc->snap_flush_lock);
1365a8599bd8SSage Weil 	list_del_init(&ci->i_snap_flush_item);
1366a8599bd8SSage Weil 	spin_unlock(&mdsc->snap_flush_lock);
1367a8599bd8SSage Weil 
1368ca81f3f6SSage Weil out:
1369a8599bd8SSage Weil 	if (psession)
1370a8599bd8SSage Weil 		*psession = session;
1371a8599bd8SSage Weil 	else if (session) {
1372a8599bd8SSage Weil 		mutex_unlock(&session->s_mutex);
1373a8599bd8SSage Weil 		ceph_put_mds_session(session);
1374a8599bd8SSage Weil 	}
1375a8599bd8SSage Weil }
1376a8599bd8SSage Weil 
1377a8599bd8SSage Weil static void ceph_flush_snaps(struct ceph_inode_info *ci)
1378a8599bd8SSage Weil {
1379be655596SSage Weil 	spin_lock(&ci->i_ceph_lock);
1380e835124cSSage Weil 	__ceph_flush_snaps(ci, NULL, 0);
1381be655596SSage Weil 	spin_unlock(&ci->i_ceph_lock);
1382a8599bd8SSage Weil }
1383a8599bd8SSage Weil 
1384a8599bd8SSage Weil /*
1385fca65b4aSSage Weil  * Mark caps dirty.  If inode is newly dirty, return the dirty flags.
1386fca65b4aSSage Weil  * Caller is then responsible for calling __mark_inode_dirty with the
1387fca65b4aSSage Weil  * returned flags value.
138876e3b390SSage Weil  */
1389fca65b4aSSage Weil int __ceph_mark_dirty_caps(struct ceph_inode_info *ci, int mask)
139076e3b390SSage Weil {
1391640ef79dSCheng Renquan 	struct ceph_mds_client *mdsc =
13923d14c5d2SYehuda Sadeh 		ceph_sb_to_client(ci->vfs_inode.i_sb)->mdsc;
139376e3b390SSage Weil 	struct inode *inode = &ci->vfs_inode;
139476e3b390SSage Weil 	int was = ci->i_dirty_caps;
139576e3b390SSage Weil 	int dirty = 0;
139676e3b390SSage Weil 
139776e3b390SSage Weil 	dout("__mark_dirty_caps %p %s dirty %s -> %s\n", &ci->vfs_inode,
139876e3b390SSage Weil 	     ceph_cap_string(mask), ceph_cap_string(was),
139976e3b390SSage Weil 	     ceph_cap_string(was | mask));
140076e3b390SSage Weil 	ci->i_dirty_caps |= mask;
140176e3b390SSage Weil 	if (was == 0) {
14027d8cb26dSSage Weil 		if (!ci->i_head_snapc)
14037d8cb26dSSage Weil 			ci->i_head_snapc = ceph_get_snap_context(
14047d8cb26dSSage Weil 				ci->i_snap_realm->cached_context);
14050685235fSYan, Zheng 		dout(" inode %p now dirty snapc %p auth cap %p\n",
14060685235fSYan, Zheng 		     &ci->vfs_inode, ci->i_head_snapc, ci->i_auth_cap);
140711df2dfbSYan, Zheng 		WARN_ON(!ci->i_auth_cap);
140876e3b390SSage Weil 		BUG_ON(!list_empty(&ci->i_dirty_item));
140976e3b390SSage Weil 		spin_lock(&mdsc->cap_dirty_lock);
141076e3b390SSage Weil 		list_add(&ci->i_dirty_item, &mdsc->cap_dirty);
141176e3b390SSage Weil 		spin_unlock(&mdsc->cap_dirty_lock);
141276e3b390SSage Weil 		if (ci->i_flushing_caps == 0) {
14133772d26dSSage Weil 			ihold(inode);
141476e3b390SSage Weil 			dirty |= I_DIRTY_SYNC;
141576e3b390SSage Weil 		}
141676e3b390SSage Weil 	}
141776e3b390SSage Weil 	BUG_ON(list_empty(&ci->i_dirty_item));
141876e3b390SSage Weil 	if (((was | ci->i_flushing_caps) & CEPH_CAP_FILE_BUFFER) &&
141976e3b390SSage Weil 	    (mask & CEPH_CAP_FILE_BUFFER))
142076e3b390SSage Weil 		dirty |= I_DIRTY_DATASYNC;
142176e3b390SSage Weil 	__cap_delay_requeue(mdsc, ci);
1422fca65b4aSSage Weil 	return dirty;
142376e3b390SSage Weil }
142476e3b390SSage Weil 
142576e3b390SSage Weil /*
1426a8599bd8SSage Weil  * Add dirty inode to the flushing list.  Assigned a seq number so we
1427a8599bd8SSage Weil  * can wait for caps to flush without starving.
1428cdc35f96SSage Weil  *
1429be655596SSage Weil  * Called under i_ceph_lock.
1430a8599bd8SSage Weil  */
1431cdc35f96SSage Weil static int __mark_caps_flushing(struct inode *inode,
1432a8599bd8SSage Weil 				 struct ceph_mds_session *session)
1433a8599bd8SSage Weil {
14343d14c5d2SYehuda Sadeh 	struct ceph_mds_client *mdsc = ceph_sb_to_client(inode->i_sb)->mdsc;
1435a8599bd8SSage Weil 	struct ceph_inode_info *ci = ceph_inode(inode);
1436cdc35f96SSage Weil 	int flushing;
1437a8599bd8SSage Weil 
1438cdc35f96SSage Weil 	BUG_ON(ci->i_dirty_caps == 0);
1439a8599bd8SSage Weil 	BUG_ON(list_empty(&ci->i_dirty_item));
1440cdc35f96SSage Weil 
1441cdc35f96SSage Weil 	flushing = ci->i_dirty_caps;
1442cdc35f96SSage Weil 	dout("__mark_caps_flushing flushing %s, flushing_caps %s -> %s\n",
1443cdc35f96SSage Weil 	     ceph_cap_string(flushing),
1444cdc35f96SSage Weil 	     ceph_cap_string(ci->i_flushing_caps),
1445cdc35f96SSage Weil 	     ceph_cap_string(ci->i_flushing_caps | flushing));
1446cdc35f96SSage Weil 	ci->i_flushing_caps |= flushing;
1447cdc35f96SSage Weil 	ci->i_dirty_caps = 0;
1448afcdaea3SSage Weil 	dout(" inode %p now !dirty\n", inode);
1449cdc35f96SSage Weil 
1450a8599bd8SSage Weil 	spin_lock(&mdsc->cap_dirty_lock);
1451cdc35f96SSage Weil 	list_del_init(&ci->i_dirty_item);
1452afcdaea3SSage Weil 
1453afcdaea3SSage Weil 	if (list_empty(&ci->i_flushing_item)) {
1454d3383a8eSYan, Zheng 		ci->i_cap_flush_seq = ++mdsc->cap_flush_seq;
1455a8599bd8SSage Weil 		list_add_tail(&ci->i_flushing_item, &session->s_cap_flushing);
1456a8599bd8SSage Weil 		mdsc->num_cap_flushing++;
1457afcdaea3SSage Weil 		dout(" inode %p now flushing seq %lld\n", inode,
1458afcdaea3SSage Weil 		     ci->i_cap_flush_seq);
1459afcdaea3SSage Weil 	} else {
1460afcdaea3SSage Weil 		list_move_tail(&ci->i_flushing_item, &session->s_cap_flushing);
1461afcdaea3SSage Weil 		dout(" inode %p now flushing (more) seq %lld\n", inode,
1462a8599bd8SSage Weil 		     ci->i_cap_flush_seq);
1463a8599bd8SSage Weil 	}
1464a8599bd8SSage Weil 	spin_unlock(&mdsc->cap_dirty_lock);
1465cdc35f96SSage Weil 
1466cdc35f96SSage Weil 	return flushing;
1467a8599bd8SSage Weil }
1468a8599bd8SSage Weil 
1469a8599bd8SSage Weil /*
14705ecad6fdSSage Weil  * try to invalidate mapping pages without blocking.
14715ecad6fdSSage Weil  */
14725ecad6fdSSage Weil static int try_nonblocking_invalidate(struct inode *inode)
14735ecad6fdSSage Weil {
14745ecad6fdSSage Weil 	struct ceph_inode_info *ci = ceph_inode(inode);
14755ecad6fdSSage Weil 	u32 invalidating_gen = ci->i_rdcache_gen;
14765ecad6fdSSage Weil 
1477be655596SSage Weil 	spin_unlock(&ci->i_ceph_lock);
14785ecad6fdSSage Weil 	invalidate_mapping_pages(&inode->i_data, 0, -1);
1479be655596SSage Weil 	spin_lock(&ci->i_ceph_lock);
14805ecad6fdSSage Weil 
148118a38193SSage Weil 	if (inode->i_data.nrpages == 0 &&
14825ecad6fdSSage Weil 	    invalidating_gen == ci->i_rdcache_gen) {
14835ecad6fdSSage Weil 		/* success. */
14845ecad6fdSSage Weil 		dout("try_nonblocking_invalidate %p success\n", inode);
1485cd045cb4SSage Weil 		/* save any racing async invalidate some trouble */
1486cd045cb4SSage Weil 		ci->i_rdcache_revoking = ci->i_rdcache_gen - 1;
14875ecad6fdSSage Weil 		return 0;
14885ecad6fdSSage Weil 	}
14895ecad6fdSSage Weil 	dout("try_nonblocking_invalidate %p failed\n", inode);
14905ecad6fdSSage Weil 	return -1;
14915ecad6fdSSage Weil }
14925ecad6fdSSage Weil 
14935ecad6fdSSage Weil /*
1494a8599bd8SSage Weil  * Swiss army knife function to examine currently used and wanted
1495a8599bd8SSage Weil  * versus held caps.  Release, flush, ack revoked caps to mds as
1496a8599bd8SSage Weil  * appropriate.
1497a8599bd8SSage Weil  *
1498a8599bd8SSage Weil  *  CHECK_CAPS_NODELAY - caller is delayed work and we should not delay
1499a8599bd8SSage Weil  *    cap release further.
1500a8599bd8SSage Weil  *  CHECK_CAPS_AUTHONLY - we should only check the auth cap
1501a8599bd8SSage Weil  *  CHECK_CAPS_FLUSH - we should flush any dirty caps immediately, without
1502a8599bd8SSage Weil  *    further delay.
1503a8599bd8SSage Weil  */
1504a8599bd8SSage Weil void ceph_check_caps(struct ceph_inode_info *ci, int flags,
1505a8599bd8SSage Weil 		     struct ceph_mds_session *session)
1506a8599bd8SSage Weil {
15073d14c5d2SYehuda Sadeh 	struct ceph_fs_client *fsc = ceph_inode_to_client(&ci->vfs_inode);
15083d14c5d2SYehuda Sadeh 	struct ceph_mds_client *mdsc = fsc->mdsc;
1509a8599bd8SSage Weil 	struct inode *inode = &ci->vfs_inode;
1510a8599bd8SSage Weil 	struct ceph_cap *cap;
1511395c312bSYan, Zheng 	int file_wanted, used, cap_used;
1512a8599bd8SSage Weil 	int took_snap_rwsem = 0;             /* true if mdsc->snap_rwsem held */
1513cbd03635SSage Weil 	int issued, implemented, want, retain, revoking, flushing = 0;
1514a8599bd8SSage Weil 	int mds = -1;   /* keep track of how far we've gone through i_caps list
1515a8599bd8SSage Weil 			   to avoid an infinite loop on retry */
1516a8599bd8SSage Weil 	struct rb_node *p;
1517a8599bd8SSage Weil 	int tried_invalidate = 0;
1518a8599bd8SSage Weil 	int delayed = 0, sent = 0, force_requeue = 0, num;
1519cbd03635SSage Weil 	int queue_invalidate = 0;
1520a8599bd8SSage Weil 	int is_delayed = flags & CHECK_CAPS_NODELAY;
1521a8599bd8SSage Weil 
1522a8599bd8SSage Weil 	/* if we are unmounting, flush any unused caps immediately. */
1523a8599bd8SSage Weil 	if (mdsc->stopping)
1524a8599bd8SSage Weil 		is_delayed = 1;
1525a8599bd8SSage Weil 
1526be655596SSage Weil 	spin_lock(&ci->i_ceph_lock);
1527a8599bd8SSage Weil 
1528a8599bd8SSage Weil 	if (ci->i_ceph_flags & CEPH_I_FLUSH)
1529a8599bd8SSage Weil 		flags |= CHECK_CAPS_FLUSH;
1530a8599bd8SSage Weil 
1531a8599bd8SSage Weil 	/* flush snaps first time around only */
1532a8599bd8SSage Weil 	if (!list_empty(&ci->i_cap_snaps))
1533e835124cSSage Weil 		__ceph_flush_snaps(ci, &session, 0);
1534a8599bd8SSage Weil 	goto retry_locked;
1535a8599bd8SSage Weil retry:
1536be655596SSage Weil 	spin_lock(&ci->i_ceph_lock);
1537a8599bd8SSage Weil retry_locked:
1538a8599bd8SSage Weil 	file_wanted = __ceph_caps_file_wanted(ci);
1539a8599bd8SSage Weil 	used = __ceph_caps_used(ci);
1540a8599bd8SSage Weil 	want = file_wanted | used;
1541cbd03635SSage Weil 	issued = __ceph_caps_issued(ci, &implemented);
1542cbd03635SSage Weil 	revoking = implemented & ~issued;
1543a8599bd8SSage Weil 
1544a8599bd8SSage Weil 	retain = want | CEPH_CAP_PIN;
1545a8599bd8SSage Weil 	if (!mdsc->stopping && inode->i_nlink > 0) {
1546a8599bd8SSage Weil 		if (want) {
1547a8599bd8SSage Weil 			retain |= CEPH_CAP_ANY;       /* be greedy */
1548a8599bd8SSage Weil 		} else {
1549a8599bd8SSage Weil 			retain |= CEPH_CAP_ANY_SHARED;
1550a8599bd8SSage Weil 			/*
1551a8599bd8SSage Weil 			 * keep RD only if we didn't have the file open RW,
1552a8599bd8SSage Weil 			 * because then the mds would revoke it anyway to
1553a8599bd8SSage Weil 			 * journal max_size=0.
1554a8599bd8SSage Weil 			 */
1555a8599bd8SSage Weil 			if (ci->i_max_size == 0)
1556a8599bd8SSage Weil 				retain |= CEPH_CAP_ANY_RD;
1557a8599bd8SSage Weil 		}
1558a8599bd8SSage Weil 	}
1559a8599bd8SSage Weil 
1560a8599bd8SSage Weil 	dout("check_caps %p file_want %s used %s dirty %s flushing %s"
1561cbd03635SSage Weil 	     " issued %s revoking %s retain %s %s%s%s\n", inode,
1562a8599bd8SSage Weil 	     ceph_cap_string(file_wanted),
1563a8599bd8SSage Weil 	     ceph_cap_string(used), ceph_cap_string(ci->i_dirty_caps),
1564a8599bd8SSage Weil 	     ceph_cap_string(ci->i_flushing_caps),
1565cbd03635SSage Weil 	     ceph_cap_string(issued), ceph_cap_string(revoking),
1566a8599bd8SSage Weil 	     ceph_cap_string(retain),
1567a8599bd8SSage Weil 	     (flags & CHECK_CAPS_AUTHONLY) ? " AUTHONLY" : "",
1568a8599bd8SSage Weil 	     (flags & CHECK_CAPS_NODELAY) ? " NODELAY" : "",
1569a8599bd8SSage Weil 	     (flags & CHECK_CAPS_FLUSH) ? " FLUSH" : "");
1570a8599bd8SSage Weil 
1571a8599bd8SSage Weil 	/*
1572a8599bd8SSage Weil 	 * If we no longer need to hold onto old our caps, and we may
1573a8599bd8SSage Weil 	 * have cached pages, but don't want them, then try to invalidate.
1574a8599bd8SSage Weil 	 * If we fail, it's because pages are locked.... try again later.
1575a8599bd8SSage Weil 	 */
1576a8599bd8SSage Weil 	if ((!is_delayed || mdsc->stopping) &&
1577a8599bd8SSage Weil 	    ci->i_wrbuffer_ref == 0 &&               /* no dirty pages... */
157893afd449SSage Weil 	    inode->i_data.nrpages &&                 /* have cached pages */
1579cbd03635SSage Weil 	    (file_wanted == 0 ||                     /* no open files */
15802962507cSSage Weil 	     (revoking & (CEPH_CAP_FILE_CACHE|
15812962507cSSage Weil 			  CEPH_CAP_FILE_LAZYIO))) && /*  or revoking cache */
1582a8599bd8SSage Weil 	    !tried_invalidate) {
1583a8599bd8SSage Weil 		dout("check_caps trying to invalidate on %p\n", inode);
15845ecad6fdSSage Weil 		if (try_nonblocking_invalidate(inode) < 0) {
15852962507cSSage Weil 			if (revoking & (CEPH_CAP_FILE_CACHE|
15862962507cSSage Weil 					CEPH_CAP_FILE_LAZYIO)) {
1587cbd03635SSage Weil 				dout("check_caps queuing invalidate\n");
1588cbd03635SSage Weil 				queue_invalidate = 1;
1589cbd03635SSage Weil 				ci->i_rdcache_revoking = ci->i_rdcache_gen;
1590a8599bd8SSage Weil 			} else {
1591a8599bd8SSage Weil 				dout("check_caps failed to invalidate pages\n");
1592a8599bd8SSage Weil 				/* we failed to invalidate pages.  check these
1593a8599bd8SSage Weil 				   caps again later. */
1594a8599bd8SSage Weil 				force_requeue = 1;
1595a8599bd8SSage Weil 				__cap_set_timeouts(mdsc, ci);
1596a8599bd8SSage Weil 			}
15975ecad6fdSSage Weil 		}
1598a8599bd8SSage Weil 		tried_invalidate = 1;
1599a8599bd8SSage Weil 		goto retry_locked;
1600a8599bd8SSage Weil 	}
1601a8599bd8SSage Weil 
1602a8599bd8SSage Weil 	num = 0;
1603a8599bd8SSage Weil 	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
1604a8599bd8SSage Weil 		cap = rb_entry(p, struct ceph_cap, ci_node);
1605a8599bd8SSage Weil 		num++;
1606a8599bd8SSage Weil 
1607a8599bd8SSage Weil 		/* avoid looping forever */
1608a8599bd8SSage Weil 		if (mds >= cap->mds ||
1609a8599bd8SSage Weil 		    ((flags & CHECK_CAPS_AUTHONLY) && cap != ci->i_auth_cap))
1610a8599bd8SSage Weil 			continue;
1611a8599bd8SSage Weil 
1612a8599bd8SSage Weil 		/* NOTE: no side-effects allowed, until we take s_mutex */
1613a8599bd8SSage Weil 
1614395c312bSYan, Zheng 		cap_used = used;
1615395c312bSYan, Zheng 		if (ci->i_auth_cap && cap != ci->i_auth_cap)
1616395c312bSYan, Zheng 			cap_used &= ~ci->i_auth_cap->issued;
1617395c312bSYan, Zheng 
1618a8599bd8SSage Weil 		revoking = cap->implemented & ~cap->issued;
1619395c312bSYan, Zheng 		dout(" mds%d cap %p used %s issued %s implemented %s revoking %s\n",
1620088b3f5eSSage Weil 		     cap->mds, cap, ceph_cap_string(cap->issued),
1621395c312bSYan, Zheng 		     ceph_cap_string(cap_used),
1622088b3f5eSSage Weil 		     ceph_cap_string(cap->implemented),
1623a8599bd8SSage Weil 		     ceph_cap_string(revoking));
1624a8599bd8SSage Weil 
1625a8599bd8SSage Weil 		if (cap == ci->i_auth_cap &&
1626a8599bd8SSage Weil 		    (cap->issued & CEPH_CAP_FILE_WR)) {
1627a8599bd8SSage Weil 			/* request larger max_size from MDS? */
1628a8599bd8SSage Weil 			if (ci->i_wanted_max_size > ci->i_max_size &&
1629a8599bd8SSage Weil 			    ci->i_wanted_max_size > ci->i_requested_max_size) {
1630a8599bd8SSage Weil 				dout("requesting new max_size\n");
1631a8599bd8SSage Weil 				goto ack;
1632a8599bd8SSage Weil 			}
1633a8599bd8SSage Weil 
1634a8599bd8SSage Weil 			/* approaching file_max? */
1635a8599bd8SSage Weil 			if ((inode->i_size << 1) >= ci->i_max_size &&
1636a8599bd8SSage Weil 			    (ci->i_reported_size << 1) < ci->i_max_size) {
1637a8599bd8SSage Weil 				dout("i_size approaching max_size\n");
1638a8599bd8SSage Weil 				goto ack;
1639a8599bd8SSage Weil 			}
1640a8599bd8SSage Weil 		}
1641a8599bd8SSage Weil 		/* flush anything dirty? */
1642a8599bd8SSage Weil 		if (cap == ci->i_auth_cap && (flags & CHECK_CAPS_FLUSH) &&
1643a8599bd8SSage Weil 		    ci->i_dirty_caps) {
1644a8599bd8SSage Weil 			dout("flushing dirty caps\n");
1645a8599bd8SSage Weil 			goto ack;
1646a8599bd8SSage Weil 		}
1647a8599bd8SSage Weil 
1648a8599bd8SSage Weil 		/* completed revocation? going down and there are no caps? */
1649395c312bSYan, Zheng 		if (revoking && (revoking & cap_used) == 0) {
1650a8599bd8SSage Weil 			dout("completed revocation of %s\n",
1651a8599bd8SSage Weil 			     ceph_cap_string(cap->implemented & ~cap->issued));
1652a8599bd8SSage Weil 			goto ack;
1653a8599bd8SSage Weil 		}
1654a8599bd8SSage Weil 
1655a8599bd8SSage Weil 		/* want more caps from mds? */
1656a8599bd8SSage Weil 		if (want & ~(cap->mds_wanted | cap->issued))
1657a8599bd8SSage Weil 			goto ack;
1658a8599bd8SSage Weil 
1659a8599bd8SSage Weil 		/* things we might delay */
1660a8599bd8SSage Weil 		if ((cap->issued & ~retain) == 0 &&
1661a8599bd8SSage Weil 		    cap->mds_wanted == want)
1662a8599bd8SSage Weil 			continue;     /* nope, all good */
1663a8599bd8SSage Weil 
1664a8599bd8SSage Weil 		if (is_delayed)
1665a8599bd8SSage Weil 			goto ack;
1666a8599bd8SSage Weil 
1667a8599bd8SSage Weil 		/* delay? */
1668a8599bd8SSage Weil 		if ((ci->i_ceph_flags & CEPH_I_NODELAY) == 0 &&
1669a8599bd8SSage Weil 		    time_before(jiffies, ci->i_hold_caps_max)) {
1670a8599bd8SSage Weil 			dout(" delaying issued %s -> %s, wanted %s -> %s\n",
1671a8599bd8SSage Weil 			     ceph_cap_string(cap->issued),
1672a8599bd8SSage Weil 			     ceph_cap_string(cap->issued & retain),
1673a8599bd8SSage Weil 			     ceph_cap_string(cap->mds_wanted),
1674a8599bd8SSage Weil 			     ceph_cap_string(want));
1675a8599bd8SSage Weil 			delayed++;
1676a8599bd8SSage Weil 			continue;
1677a8599bd8SSage Weil 		}
1678a8599bd8SSage Weil 
1679a8599bd8SSage Weil ack:
1680e9964c10SSage Weil 		if (ci->i_ceph_flags & CEPH_I_NOFLUSH) {
1681e9964c10SSage Weil 			dout(" skipping %p I_NOFLUSH set\n", inode);
1682e9964c10SSage Weil 			continue;
1683e9964c10SSage Weil 		}
1684e9964c10SSage Weil 
1685a8599bd8SSage Weil 		if (session && session != cap->session) {
1686a8599bd8SSage Weil 			dout("oops, wrong session %p mutex\n", session);
1687a8599bd8SSage Weil 			mutex_unlock(&session->s_mutex);
1688a8599bd8SSage Weil 			session = NULL;
1689a8599bd8SSage Weil 		}
1690a8599bd8SSage Weil 		if (!session) {
1691a8599bd8SSage Weil 			session = cap->session;
1692a8599bd8SSage Weil 			if (mutex_trylock(&session->s_mutex) == 0) {
1693a8599bd8SSage Weil 				dout("inverting session/ino locks on %p\n",
1694a8599bd8SSage Weil 				     session);
1695be655596SSage Weil 				spin_unlock(&ci->i_ceph_lock);
1696a8599bd8SSage Weil 				if (took_snap_rwsem) {
1697a8599bd8SSage Weil 					up_read(&mdsc->snap_rwsem);
1698a8599bd8SSage Weil 					took_snap_rwsem = 0;
1699a8599bd8SSage Weil 				}
1700a8599bd8SSage Weil 				mutex_lock(&session->s_mutex);
1701a8599bd8SSage Weil 				goto retry;
1702a8599bd8SSage Weil 			}
1703a8599bd8SSage Weil 		}
1704a8599bd8SSage Weil 		/* take snap_rwsem after session mutex */
1705a8599bd8SSage Weil 		if (!took_snap_rwsem) {
1706a8599bd8SSage Weil 			if (down_read_trylock(&mdsc->snap_rwsem) == 0) {
1707a8599bd8SSage Weil 				dout("inverting snap/in locks on %p\n",
1708a8599bd8SSage Weil 				     inode);
1709be655596SSage Weil 				spin_unlock(&ci->i_ceph_lock);
1710a8599bd8SSage Weil 				down_read(&mdsc->snap_rwsem);
1711a8599bd8SSage Weil 				took_snap_rwsem = 1;
1712a8599bd8SSage Weil 				goto retry;
1713a8599bd8SSage Weil 			}
1714a8599bd8SSage Weil 			took_snap_rwsem = 1;
1715a8599bd8SSage Weil 		}
1716a8599bd8SSage Weil 
1717cdc35f96SSage Weil 		if (cap == ci->i_auth_cap && ci->i_dirty_caps)
1718cdc35f96SSage Weil 			flushing = __mark_caps_flushing(inode, session);
171924be0c48SSage Weil 		else
172024be0c48SSage Weil 			flushing = 0;
1721a8599bd8SSage Weil 
1722a8599bd8SSage Weil 		mds = cap->mds;  /* remember mds, so we don't repeat */
1723a8599bd8SSage Weil 		sent++;
1724a8599bd8SSage Weil 
1725be655596SSage Weil 		/* __send_cap drops i_ceph_lock */
1726395c312bSYan, Zheng 		delayed += __send_cap(mdsc, cap, CEPH_CAP_OP_UPDATE, cap_used,
1727395c312bSYan, Zheng 				      want, retain, flushing, NULL);
1728be655596SSage Weil 		goto retry; /* retake i_ceph_lock and restart our cap scan. */
1729a8599bd8SSage Weil 	}
1730a8599bd8SSage Weil 
1731a8599bd8SSage Weil 	/*
1732a8599bd8SSage Weil 	 * Reschedule delayed caps release if we delayed anything,
1733a8599bd8SSage Weil 	 * otherwise cancel.
1734a8599bd8SSage Weil 	 */
1735a8599bd8SSage Weil 	if (delayed && is_delayed)
1736a8599bd8SSage Weil 		force_requeue = 1;   /* __send_cap delayed release; requeue */
1737a8599bd8SSage Weil 	if (!delayed && !is_delayed)
1738a8599bd8SSage Weil 		__cap_delay_cancel(mdsc, ci);
1739a8599bd8SSage Weil 	else if (!is_delayed || force_requeue)
1740a8599bd8SSage Weil 		__cap_delay_requeue(mdsc, ci);
1741a8599bd8SSage Weil 
1742be655596SSage Weil 	spin_unlock(&ci->i_ceph_lock);
1743a8599bd8SSage Weil 
1744cbd03635SSage Weil 	if (queue_invalidate)
17453c6f6b79SSage Weil 		ceph_queue_invalidate(inode);
1746cbd03635SSage Weil 
1747cdc2ce05SSage Weil 	if (session)
1748a8599bd8SSage Weil 		mutex_unlock(&session->s_mutex);
1749a8599bd8SSage Weil 	if (took_snap_rwsem)
1750a8599bd8SSage Weil 		up_read(&mdsc->snap_rwsem);
1751a8599bd8SSage Weil }
1752a8599bd8SSage Weil 
1753a8599bd8SSage Weil /*
1754a8599bd8SSage Weil  * Try to flush dirty caps back to the auth mds.
1755a8599bd8SSage Weil  */
17564fe59789SYan, Zheng static int try_flush_caps(struct inode *inode, unsigned *flush_tid)
1757a8599bd8SSage Weil {
17583d14c5d2SYehuda Sadeh 	struct ceph_mds_client *mdsc = ceph_sb_to_client(inode->i_sb)->mdsc;
1759a8599bd8SSage Weil 	struct ceph_inode_info *ci = ceph_inode(inode);
1760a8599bd8SSage Weil 	int flushing = 0;
17614fe59789SYan, Zheng 	struct ceph_mds_session *session = NULL;
1762a8599bd8SSage Weil 
1763a8599bd8SSage Weil retry:
1764be655596SSage Weil 	spin_lock(&ci->i_ceph_lock);
1765e9964c10SSage Weil 	if (ci->i_ceph_flags & CEPH_I_NOFLUSH) {
1766e9964c10SSage Weil 		dout("try_flush_caps skipping %p I_NOFLUSH set\n", inode);
1767e9964c10SSage Weil 		goto out;
1768e9964c10SSage Weil 	}
1769a8599bd8SSage Weil 	if (ci->i_dirty_caps && ci->i_auth_cap) {
1770a8599bd8SSage Weil 		struct ceph_cap *cap = ci->i_auth_cap;
1771a8599bd8SSage Weil 		int used = __ceph_caps_used(ci);
1772a8599bd8SSage Weil 		int want = __ceph_caps_wanted(ci);
1773a8599bd8SSage Weil 		int delayed;
1774a8599bd8SSage Weil 
17754fe59789SYan, Zheng 		if (!session || session != cap->session) {
1776be655596SSage Weil 			spin_unlock(&ci->i_ceph_lock);
17774fe59789SYan, Zheng 			if (session)
17784fe59789SYan, Zheng 				mutex_unlock(&session->s_mutex);
1779a8599bd8SSage Weil 			session = cap->session;
1780a8599bd8SSage Weil 			mutex_lock(&session->s_mutex);
1781a8599bd8SSage Weil 			goto retry;
1782a8599bd8SSage Weil 		}
1783a8599bd8SSage Weil 		if (cap->session->s_state < CEPH_MDS_SESSION_OPEN)
1784a8599bd8SSage Weil 			goto out;
1785a8599bd8SSage Weil 
1786cdc35f96SSage Weil 		flushing = __mark_caps_flushing(inode, session);
1787a8599bd8SSage Weil 
1788be655596SSage Weil 		/* __send_cap drops i_ceph_lock */
1789a8599bd8SSage Weil 		delayed = __send_cap(mdsc, cap, CEPH_CAP_OP_FLUSH, used, want,
1790a8599bd8SSage Weil 				     cap->issued | cap->implemented, flushing,
1791a8599bd8SSage Weil 				     flush_tid);
1792a8599bd8SSage Weil 		if (!delayed)
1793a8599bd8SSage Weil 			goto out_unlocked;
1794a8599bd8SSage Weil 
1795be655596SSage Weil 		spin_lock(&ci->i_ceph_lock);
1796a8599bd8SSage Weil 		__cap_delay_requeue(mdsc, ci);
1797a8599bd8SSage Weil 	}
1798a8599bd8SSage Weil out:
1799be655596SSage Weil 	spin_unlock(&ci->i_ceph_lock);
1800a8599bd8SSage Weil out_unlocked:
18014fe59789SYan, Zheng 	if (session)
1802a8599bd8SSage Weil 		mutex_unlock(&session->s_mutex);
1803a8599bd8SSage Weil 	return flushing;
1804a8599bd8SSage Weil }
1805a8599bd8SSage Weil 
1806a8599bd8SSage Weil /*
1807a8599bd8SSage Weil  * Return true if we've flushed caps through the given flush_tid.
1808a8599bd8SSage Weil  */
1809a8599bd8SSage Weil static int caps_are_flushed(struct inode *inode, unsigned tid)
1810a8599bd8SSage Weil {
1811a8599bd8SSage Weil 	struct ceph_inode_info *ci = ceph_inode(inode);
1812a5ee751cSDan Carpenter 	int i, ret = 1;
1813a8599bd8SSage Weil 
1814be655596SSage Weil 	spin_lock(&ci->i_ceph_lock);
1815a8599bd8SSage Weil 	for (i = 0; i < CEPH_CAP_BITS; i++)
1816a8599bd8SSage Weil 		if ((ci->i_flushing_caps & (1 << i)) &&
1817a8599bd8SSage Weil 		    ci->i_cap_flush_tid[i] <= tid) {
1818a8599bd8SSage Weil 			/* still flushing this bit */
1819a8599bd8SSage Weil 			ret = 0;
1820a8599bd8SSage Weil 			break;
1821a8599bd8SSage Weil 		}
1822be655596SSage Weil 	spin_unlock(&ci->i_ceph_lock);
1823a8599bd8SSage Weil 	return ret;
1824a8599bd8SSage Weil }
1825a8599bd8SSage Weil 
1826a8599bd8SSage Weil /*
1827a8599bd8SSage Weil  * Wait on any unsafe replies for the given inode.  First wait on the
1828a8599bd8SSage Weil  * newest request, and make that the upper bound.  Then, if there are
1829a8599bd8SSage Weil  * more requests, keep waiting on the oldest as long as it is still older
1830a8599bd8SSage Weil  * than the original request.
1831a8599bd8SSage Weil  */
1832a8599bd8SSage Weil static void sync_write_wait(struct inode *inode)
1833a8599bd8SSage Weil {
1834a8599bd8SSage Weil 	struct ceph_inode_info *ci = ceph_inode(inode);
1835a8599bd8SSage Weil 	struct list_head *head = &ci->i_unsafe_writes;
1836a8599bd8SSage Weil 	struct ceph_osd_request *req;
1837a8599bd8SSage Weil 	u64 last_tid;
1838a8599bd8SSage Weil 
1839a8599bd8SSage Weil 	spin_lock(&ci->i_unsafe_lock);
1840a8599bd8SSage Weil 	if (list_empty(head))
1841a8599bd8SSage Weil 		goto out;
1842a8599bd8SSage Weil 
1843a8599bd8SSage Weil 	/* set upper bound as _last_ entry in chain */
1844a8599bd8SSage Weil 	req = list_entry(head->prev, struct ceph_osd_request,
1845a8599bd8SSage Weil 			 r_unsafe_item);
1846a8599bd8SSage Weil 	last_tid = req->r_tid;
1847a8599bd8SSage Weil 
1848a8599bd8SSage Weil 	do {
1849a8599bd8SSage Weil 		ceph_osdc_get_request(req);
1850a8599bd8SSage Weil 		spin_unlock(&ci->i_unsafe_lock);
1851a8599bd8SSage Weil 		dout("sync_write_wait on tid %llu (until %llu)\n",
1852a8599bd8SSage Weil 		     req->r_tid, last_tid);
1853a8599bd8SSage Weil 		wait_for_completion(&req->r_safe_completion);
1854a8599bd8SSage Weil 		spin_lock(&ci->i_unsafe_lock);
1855a8599bd8SSage Weil 		ceph_osdc_put_request(req);
1856a8599bd8SSage Weil 
1857a8599bd8SSage Weil 		/*
1858a8599bd8SSage Weil 		 * from here on look at first entry in chain, since we
1859a8599bd8SSage Weil 		 * only want to wait for anything older than last_tid
1860a8599bd8SSage Weil 		 */
1861a8599bd8SSage Weil 		if (list_empty(head))
1862a8599bd8SSage Weil 			break;
1863a8599bd8SSage Weil 		req = list_entry(head->next, struct ceph_osd_request,
1864a8599bd8SSage Weil 				 r_unsafe_item);
1865a8599bd8SSage Weil 	} while (req->r_tid < last_tid);
1866a8599bd8SSage Weil out:
1867a8599bd8SSage Weil 	spin_unlock(&ci->i_unsafe_lock);
1868a8599bd8SSage Weil }
1869a8599bd8SSage Weil 
187002c24a82SJosef Bacik int ceph_fsync(struct file *file, loff_t start, loff_t end, int datasync)
1871a8599bd8SSage Weil {
18727ea80859SChristoph Hellwig 	struct inode *inode = file->f_mapping->host;
1873a8599bd8SSage Weil 	struct ceph_inode_info *ci = ceph_inode(inode);
1874a8599bd8SSage Weil 	unsigned flush_tid;
1875a8599bd8SSage Weil 	int ret;
1876a8599bd8SSage Weil 	int dirty;
1877a8599bd8SSage Weil 
1878a8599bd8SSage Weil 	dout("fsync %p%s\n", inode, datasync ? " datasync" : "");
1879a8599bd8SSage Weil 	sync_write_wait(inode);
1880a8599bd8SSage Weil 
188102c24a82SJosef Bacik 	ret = filemap_write_and_wait_range(inode->i_mapping, start, end);
1882a8599bd8SSage Weil 	if (ret < 0)
1883a8599bd8SSage Weil 		return ret;
188402c24a82SJosef Bacik 	mutex_lock(&inode->i_mutex);
1885a8599bd8SSage Weil 
18864fe59789SYan, Zheng 	dirty = try_flush_caps(inode, &flush_tid);
1887a8599bd8SSage Weil 	dout("fsync dirty caps are %s\n", ceph_cap_string(dirty));
1888a8599bd8SSage Weil 
1889a8599bd8SSage Weil 	/*
1890a8599bd8SSage Weil 	 * only wait on non-file metadata writeback (the mds
1891a8599bd8SSage Weil 	 * can recover size and mtime, so we don't need to
1892a8599bd8SSage Weil 	 * wait for that)
1893a8599bd8SSage Weil 	 */
1894a8599bd8SSage Weil 	if (!datasync && (dirty & ~CEPH_CAP_ANY_FILE_WR)) {
1895a8599bd8SSage Weil 		dout("fsync waiting for flush_tid %u\n", flush_tid);
1896a8599bd8SSage Weil 		ret = wait_event_interruptible(ci->i_cap_wq,
1897a8599bd8SSage Weil 				       caps_are_flushed(inode, flush_tid));
1898a8599bd8SSage Weil 	}
1899a8599bd8SSage Weil 
1900a8599bd8SSage Weil 	dout("fsync %p%s done\n", inode, datasync ? " datasync" : "");
190102c24a82SJosef Bacik 	mutex_unlock(&inode->i_mutex);
1902a8599bd8SSage Weil 	return ret;
1903a8599bd8SSage Weil }
1904a8599bd8SSage Weil 
1905a8599bd8SSage Weil /*
1906a8599bd8SSage Weil  * Flush any dirty caps back to the mds.  If we aren't asked to wait,
1907a8599bd8SSage Weil  * queue inode for flush but don't do so immediately, because we can
1908a8599bd8SSage Weil  * get by with fewer MDS messages if we wait for data writeback to
1909a8599bd8SSage Weil  * complete first.
1910a8599bd8SSage Weil  */
1911f1a3d572SStephen Rothwell int ceph_write_inode(struct inode *inode, struct writeback_control *wbc)
1912a8599bd8SSage Weil {
1913a8599bd8SSage Weil 	struct ceph_inode_info *ci = ceph_inode(inode);
1914a8599bd8SSage Weil 	unsigned flush_tid;
1915a8599bd8SSage Weil 	int err = 0;
1916a8599bd8SSage Weil 	int dirty;
1917f1a3d572SStephen Rothwell 	int wait = wbc->sync_mode == WB_SYNC_ALL;
1918a8599bd8SSage Weil 
1919a8599bd8SSage Weil 	dout("write_inode %p wait=%d\n", inode, wait);
1920a8599bd8SSage Weil 	if (wait) {
19214fe59789SYan, Zheng 		dirty = try_flush_caps(inode, &flush_tid);
1922a8599bd8SSage Weil 		if (dirty)
1923a8599bd8SSage Weil 			err = wait_event_interruptible(ci->i_cap_wq,
1924a8599bd8SSage Weil 				       caps_are_flushed(inode, flush_tid));
1925a8599bd8SSage Weil 	} else {
1926640ef79dSCheng Renquan 		struct ceph_mds_client *mdsc =
19273d14c5d2SYehuda Sadeh 			ceph_sb_to_client(inode->i_sb)->mdsc;
1928a8599bd8SSage Weil 
1929be655596SSage Weil 		spin_lock(&ci->i_ceph_lock);
1930a8599bd8SSage Weil 		if (__ceph_caps_dirty(ci))
1931a8599bd8SSage Weil 			__cap_delay_requeue_front(mdsc, ci);
1932be655596SSage Weil 		spin_unlock(&ci->i_ceph_lock);
1933a8599bd8SSage Weil 	}
1934a8599bd8SSage Weil 	return err;
1935a8599bd8SSage Weil }
1936a8599bd8SSage Weil 
1937a8599bd8SSage Weil /*
1938a8599bd8SSage Weil  * After a recovering MDS goes active, we need to resend any caps
1939a8599bd8SSage Weil  * we were flushing.
1940a8599bd8SSage Weil  *
1941a8599bd8SSage Weil  * Caller holds session->s_mutex.
1942a8599bd8SSage Weil  */
1943a8599bd8SSage Weil static void kick_flushing_capsnaps(struct ceph_mds_client *mdsc,
1944a8599bd8SSage Weil 				   struct ceph_mds_session *session)
1945a8599bd8SSage Weil {
1946a8599bd8SSage Weil 	struct ceph_cap_snap *capsnap;
1947a8599bd8SSage Weil 
1948a8599bd8SSage Weil 	dout("kick_flushing_capsnaps mds%d\n", session->s_mds);
1949a8599bd8SSage Weil 	list_for_each_entry(capsnap, &session->s_cap_snaps_flushing,
1950a8599bd8SSage Weil 			    flushing_item) {
1951a8599bd8SSage Weil 		struct ceph_inode_info *ci = capsnap->ci;
1952a8599bd8SSage Weil 		struct inode *inode = &ci->vfs_inode;
1953a8599bd8SSage Weil 		struct ceph_cap *cap;
1954a8599bd8SSage Weil 
1955be655596SSage Weil 		spin_lock(&ci->i_ceph_lock);
1956a8599bd8SSage Weil 		cap = ci->i_auth_cap;
1957a8599bd8SSage Weil 		if (cap && cap->session == session) {
1958a8599bd8SSage Weil 			dout("kick_flushing_caps %p cap %p capsnap %p\n", inode,
1959a8599bd8SSage Weil 			     cap, capsnap);
1960e835124cSSage Weil 			__ceph_flush_snaps(ci, &session, 1);
1961a8599bd8SSage Weil 		} else {
1962a8599bd8SSage Weil 			pr_err("%p auth cap %p not mds%d ???\n", inode,
1963a8599bd8SSage Weil 			       cap, session->s_mds);
1964a8599bd8SSage Weil 		}
1965be655596SSage Weil 		spin_unlock(&ci->i_ceph_lock);
1966a8599bd8SSage Weil 	}
1967a8599bd8SSage Weil }
1968a8599bd8SSage Weil 
1969a8599bd8SSage Weil void ceph_kick_flushing_caps(struct ceph_mds_client *mdsc,
1970a8599bd8SSage Weil 			     struct ceph_mds_session *session)
1971a8599bd8SSage Weil {
1972a8599bd8SSage Weil 	struct ceph_inode_info *ci;
1973a8599bd8SSage Weil 
1974a8599bd8SSage Weil 	kick_flushing_capsnaps(mdsc, session);
1975a8599bd8SSage Weil 
1976a8599bd8SSage Weil 	dout("kick_flushing_caps mds%d\n", session->s_mds);
1977a8599bd8SSage Weil 	list_for_each_entry(ci, &session->s_cap_flushing, i_flushing_item) {
1978a8599bd8SSage Weil 		struct inode *inode = &ci->vfs_inode;
1979a8599bd8SSage Weil 		struct ceph_cap *cap;
1980a8599bd8SSage Weil 		int delayed = 0;
1981a8599bd8SSage Weil 
1982be655596SSage Weil 		spin_lock(&ci->i_ceph_lock);
1983a8599bd8SSage Weil 		cap = ci->i_auth_cap;
1984a8599bd8SSage Weil 		if (cap && cap->session == session) {
1985a8599bd8SSage Weil 			dout("kick_flushing_caps %p cap %p %s\n", inode,
1986a8599bd8SSage Weil 			     cap, ceph_cap_string(ci->i_flushing_caps));
1987a8599bd8SSage Weil 			delayed = __send_cap(mdsc, cap, CEPH_CAP_OP_FLUSH,
1988a8599bd8SSage Weil 					     __ceph_caps_used(ci),
1989a8599bd8SSage Weil 					     __ceph_caps_wanted(ci),
1990a8599bd8SSage Weil 					     cap->issued | cap->implemented,
1991a8599bd8SSage Weil 					     ci->i_flushing_caps, NULL);
1992a8599bd8SSage Weil 			if (delayed) {
1993be655596SSage Weil 				spin_lock(&ci->i_ceph_lock);
1994a8599bd8SSage Weil 				__cap_delay_requeue(mdsc, ci);
1995be655596SSage Weil 				spin_unlock(&ci->i_ceph_lock);
1996a8599bd8SSage Weil 			}
1997a8599bd8SSage Weil 		} else {
1998a8599bd8SSage Weil 			pr_err("%p auth cap %p not mds%d ???\n", inode,
1999a8599bd8SSage Weil 			       cap, session->s_mds);
2000be655596SSage Weil 			spin_unlock(&ci->i_ceph_lock);
2001a8599bd8SSage Weil 		}
2002a8599bd8SSage Weil 	}
2003a8599bd8SSage Weil }
2004a8599bd8SSage Weil 
2005088b3f5eSSage Weil static void kick_flushing_inode_caps(struct ceph_mds_client *mdsc,
2006088b3f5eSSage Weil 				     struct ceph_mds_session *session,
2007088b3f5eSSage Weil 				     struct inode *inode)
2008088b3f5eSSage Weil {
2009088b3f5eSSage Weil 	struct ceph_inode_info *ci = ceph_inode(inode);
2010088b3f5eSSage Weil 	struct ceph_cap *cap;
2011088b3f5eSSage Weil 	int delayed = 0;
2012088b3f5eSSage Weil 
2013be655596SSage Weil 	spin_lock(&ci->i_ceph_lock);
2014088b3f5eSSage Weil 	cap = ci->i_auth_cap;
2015088b3f5eSSage Weil 	dout("kick_flushing_inode_caps %p flushing %s flush_seq %lld\n", inode,
2016088b3f5eSSage Weil 	     ceph_cap_string(ci->i_flushing_caps), ci->i_cap_flush_seq);
2017005c4697SYan, Zheng 
2018088b3f5eSSage Weil 	__ceph_flush_snaps(ci, &session, 1);
2019005c4697SYan, Zheng 
2020088b3f5eSSage Weil 	if (ci->i_flushing_caps) {
2021005c4697SYan, Zheng 		spin_lock(&mdsc->cap_dirty_lock);
2022005c4697SYan, Zheng 		list_move_tail(&ci->i_flushing_item,
2023005c4697SYan, Zheng 			       &cap->session->s_cap_flushing);
2024005c4697SYan, Zheng 		spin_unlock(&mdsc->cap_dirty_lock);
2025005c4697SYan, Zheng 
2026088b3f5eSSage Weil 		delayed = __send_cap(mdsc, cap, CEPH_CAP_OP_FLUSH,
2027088b3f5eSSage Weil 				     __ceph_caps_used(ci),
2028088b3f5eSSage Weil 				     __ceph_caps_wanted(ci),
2029088b3f5eSSage Weil 				     cap->issued | cap->implemented,
2030088b3f5eSSage Weil 				     ci->i_flushing_caps, NULL);
2031088b3f5eSSage Weil 		if (delayed) {
2032be655596SSage Weil 			spin_lock(&ci->i_ceph_lock);
2033088b3f5eSSage Weil 			__cap_delay_requeue(mdsc, ci);
2034be655596SSage Weil 			spin_unlock(&ci->i_ceph_lock);
2035088b3f5eSSage Weil 		}
2036088b3f5eSSage Weil 	} else {
2037be655596SSage Weil 		spin_unlock(&ci->i_ceph_lock);
2038088b3f5eSSage Weil 	}
2039088b3f5eSSage Weil }
2040088b3f5eSSage Weil 
2041a8599bd8SSage Weil 
2042a8599bd8SSage Weil /*
2043a8599bd8SSage Weil  * Take references to capabilities we hold, so that we don't release
2044a8599bd8SSage Weil  * them to the MDS prematurely.
2045a8599bd8SSage Weil  *
2046be655596SSage Weil  * Protected by i_ceph_lock.
2047a8599bd8SSage Weil  */
2048a8599bd8SSage Weil static void __take_cap_refs(struct ceph_inode_info *ci, int got)
2049a8599bd8SSage Weil {
2050a8599bd8SSage Weil 	if (got & CEPH_CAP_PIN)
2051a8599bd8SSage Weil 		ci->i_pin_ref++;
2052a8599bd8SSage Weil 	if (got & CEPH_CAP_FILE_RD)
2053a8599bd8SSage Weil 		ci->i_rd_ref++;
2054a8599bd8SSage Weil 	if (got & CEPH_CAP_FILE_CACHE)
2055a8599bd8SSage Weil 		ci->i_rdcache_ref++;
2056a8599bd8SSage Weil 	if (got & CEPH_CAP_FILE_WR)
2057a8599bd8SSage Weil 		ci->i_wr_ref++;
2058a8599bd8SSage Weil 	if (got & CEPH_CAP_FILE_BUFFER) {
2059d3d0720dSHenry C Chang 		if (ci->i_wb_ref == 0)
20603772d26dSSage Weil 			ihold(&ci->vfs_inode);
2061d3d0720dSHenry C Chang 		ci->i_wb_ref++;
2062d3d0720dSHenry C Chang 		dout("__take_cap_refs %p wb %d -> %d (?)\n",
2063d3d0720dSHenry C Chang 		     &ci->vfs_inode, ci->i_wb_ref-1, ci->i_wb_ref);
2064a8599bd8SSage Weil 	}
2065a8599bd8SSage Weil }
2066a8599bd8SSage Weil 
2067a8599bd8SSage Weil /*
2068a8599bd8SSage Weil  * Try to grab cap references.  Specify those refs we @want, and the
2069a8599bd8SSage Weil  * minimal set we @need.  Also include the larger offset we are writing
2070a8599bd8SSage Weil  * to (when applicable), and check against max_size here as well.
2071a8599bd8SSage Weil  * Note that caller is responsible for ensuring max_size increases are
2072a8599bd8SSage Weil  * requested from the MDS.
2073a8599bd8SSage Weil  */
2074a8599bd8SSage Weil static int try_get_cap_refs(struct ceph_inode_info *ci, int need, int want,
20753738daa6SYan, Zheng 			    loff_t endoff, int *got, struct page **pinned_page,
20763738daa6SYan, Zheng 			    int *check_max, int *err)
2077a8599bd8SSage Weil {
2078a8599bd8SSage Weil 	struct inode *inode = &ci->vfs_inode;
2079a8599bd8SSage Weil 	int ret = 0;
20803738daa6SYan, Zheng 	int have, implemented, _got = 0;
2081195d3ce2SSage Weil 	int file_wanted;
2082a8599bd8SSage Weil 
2083a8599bd8SSage Weil 	dout("get_cap_refs %p need %s want %s\n", inode,
2084a8599bd8SSage Weil 	     ceph_cap_string(need), ceph_cap_string(want));
20853738daa6SYan, Zheng again:
2086be655596SSage Weil 	spin_lock(&ci->i_ceph_lock);
2087a8599bd8SSage Weil 
2088195d3ce2SSage Weil 	/* make sure file is actually open */
2089195d3ce2SSage Weil 	file_wanted = __ceph_caps_file_wanted(ci);
2090195d3ce2SSage Weil 	if ((file_wanted & need) == 0) {
2091195d3ce2SSage Weil 		dout("try_get_cap_refs need %s file_wanted %s, EBADF\n",
2092195d3ce2SSage Weil 		     ceph_cap_string(need), ceph_cap_string(file_wanted));
2093a8599bd8SSage Weil 		*err = -EBADF;
2094a8599bd8SSage Weil 		ret = 1;
20953738daa6SYan, Zheng 		goto out_unlock;
2096a8599bd8SSage Weil 	}
2097a8599bd8SSage Weil 
209837505d57SYan, Zheng 	/* finish pending truncate */
209937505d57SYan, Zheng 	while (ci->i_truncate_pending) {
210037505d57SYan, Zheng 		spin_unlock(&ci->i_ceph_lock);
2101b415bf4fSYan, Zheng 		__ceph_do_pending_vmtruncate(inode);
210237505d57SYan, Zheng 		spin_lock(&ci->i_ceph_lock);
210337505d57SYan, Zheng 	}
210437505d57SYan, Zheng 
21053871cbb9SYan, Zheng 	have = __ceph_caps_issued(ci, &implemented);
21063871cbb9SYan, Zheng 
21073871cbb9SYan, Zheng 	if (have & need & CEPH_CAP_FILE_WR) {
2108a8599bd8SSage Weil 		if (endoff >= 0 && endoff > (loff_t)ci->i_max_size) {
2109a8599bd8SSage Weil 			dout("get_cap_refs %p endoff %llu > maxsize %llu\n",
2110a8599bd8SSage Weil 			     inode, endoff, ci->i_max_size);
21113871cbb9SYan, Zheng 			if (endoff > ci->i_requested_max_size) {
2112a8599bd8SSage Weil 				*check_max = 1;
2113a8599bd8SSage Weil 				ret = 1;
2114a8599bd8SSage Weil 			}
21153738daa6SYan, Zheng 			goto out_unlock;
2116a8599bd8SSage Weil 		}
2117a8599bd8SSage Weil 		/*
2118a8599bd8SSage Weil 		 * If a sync write is in progress, we must wait, so that we
2119a8599bd8SSage Weil 		 * can get a final snapshot value for size+mtime.
2120a8599bd8SSage Weil 		 */
2121a8599bd8SSage Weil 		if (__ceph_have_pending_cap_snap(ci)) {
2122a8599bd8SSage Weil 			dout("get_cap_refs %p cap_snap_pending\n", inode);
21233738daa6SYan, Zheng 			goto out_unlock;
2124a8599bd8SSage Weil 		}
2125a8599bd8SSage Weil 	}
2126a8599bd8SSage Weil 
2127a8599bd8SSage Weil 	if ((have & need) == need) {
2128a8599bd8SSage Weil 		/*
2129a8599bd8SSage Weil 		 * Look at (implemented & ~have & not) so that we keep waiting
2130a8599bd8SSage Weil 		 * on transition from wanted -> needed caps.  This is needed
2131a8599bd8SSage Weil 		 * for WRBUFFER|WR -> WR to avoid a new WR sync write from
2132a8599bd8SSage Weil 		 * going before a prior buffered writeback happens.
2133a8599bd8SSage Weil 		 */
2134a8599bd8SSage Weil 		int not = want & ~(have & need);
2135a8599bd8SSage Weil 		int revoking = implemented & ~have;
2136a8599bd8SSage Weil 		dout("get_cap_refs %p have %s but not %s (revoking %s)\n",
2137a8599bd8SSage Weil 		     inode, ceph_cap_string(have), ceph_cap_string(not),
2138a8599bd8SSage Weil 		     ceph_cap_string(revoking));
2139a8599bd8SSage Weil 		if ((revoking & not) == 0) {
21403738daa6SYan, Zheng 			_got = need | (have & want);
21413738daa6SYan, Zheng 			__take_cap_refs(ci, _got);
2142a8599bd8SSage Weil 			ret = 1;
2143a8599bd8SSage Weil 		}
2144a8599bd8SSage Weil 	} else {
214503f4fcb0SYan, Zheng 		int session_readonly = false;
214603f4fcb0SYan, Zheng 		if ((need & CEPH_CAP_FILE_WR) && ci->i_auth_cap) {
214703f4fcb0SYan, Zheng 			struct ceph_mds_session *s = ci->i_auth_cap->session;
214803f4fcb0SYan, Zheng 			spin_lock(&s->s_cap_lock);
214903f4fcb0SYan, Zheng 			session_readonly = s->s_readonly;
215003f4fcb0SYan, Zheng 			spin_unlock(&s->s_cap_lock);
215103f4fcb0SYan, Zheng 		}
215203f4fcb0SYan, Zheng 		if (session_readonly) {
215303f4fcb0SYan, Zheng 			dout("get_cap_refs %p needed %s but mds%d readonly\n",
215403f4fcb0SYan, Zheng 			     inode, ceph_cap_string(need), ci->i_auth_cap->mds);
215503f4fcb0SYan, Zheng 			*err = -EROFS;
215603f4fcb0SYan, Zheng 			ret = 1;
215703f4fcb0SYan, Zheng 			goto out_unlock;
215803f4fcb0SYan, Zheng 		}
215903f4fcb0SYan, Zheng 
2160a8599bd8SSage Weil 		dout("get_cap_refs %p have %s needed %s\n", inode,
2161a8599bd8SSage Weil 		     ceph_cap_string(have), ceph_cap_string(need));
2162a8599bd8SSage Weil 	}
21633738daa6SYan, Zheng out_unlock:
2164be655596SSage Weil 	spin_unlock(&ci->i_ceph_lock);
21653738daa6SYan, Zheng 
21663738daa6SYan, Zheng 	if (ci->i_inline_version != CEPH_INLINE_NONE &&
21673738daa6SYan, Zheng 	    (_got & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)) &&
21683738daa6SYan, Zheng 	    i_size_read(inode) > 0) {
21693738daa6SYan, Zheng 		int ret1;
21703738daa6SYan, Zheng 		struct page *page = find_get_page(inode->i_mapping, 0);
21713738daa6SYan, Zheng 		if (page) {
21723738daa6SYan, Zheng 			if (PageUptodate(page)) {
21733738daa6SYan, Zheng 				*pinned_page = page;
21743738daa6SYan, Zheng 				goto out;
21753738daa6SYan, Zheng 			}
21763738daa6SYan, Zheng 			page_cache_release(page);
21773738daa6SYan, Zheng 		}
21783738daa6SYan, Zheng 		/*
21793738daa6SYan, Zheng 		 * drop cap refs first because getattr while holding
21803738daa6SYan, Zheng 		 * caps refs can cause deadlock.
21813738daa6SYan, Zheng 		 */
21823738daa6SYan, Zheng 		ceph_put_cap_refs(ci, _got);
21833738daa6SYan, Zheng 		_got = 0;
21843738daa6SYan, Zheng 
21853738daa6SYan, Zheng 		/* getattr request will bring inline data into page cache */
21863738daa6SYan, Zheng 		ret1 = __ceph_do_getattr(inode, NULL,
21873738daa6SYan, Zheng 					 CEPH_STAT_CAP_INLINE_DATA, true);
21883738daa6SYan, Zheng 		if (ret1 >= 0) {
21893738daa6SYan, Zheng 			ret = 0;
21903738daa6SYan, Zheng 			goto again;
21913738daa6SYan, Zheng 		}
21923738daa6SYan, Zheng 		*err = ret1;
21933738daa6SYan, Zheng 		ret = 1;
21943738daa6SYan, Zheng 	}
21953738daa6SYan, Zheng out:
2196a8599bd8SSage Weil 	dout("get_cap_refs %p ret %d got %s\n", inode,
21973738daa6SYan, Zheng 	     ret, ceph_cap_string(_got));
21983738daa6SYan, Zheng 	*got = _got;
2199a8599bd8SSage Weil 	return ret;
2200a8599bd8SSage Weil }
2201a8599bd8SSage Weil 
2202a8599bd8SSage Weil /*
2203a8599bd8SSage Weil  * Check the offset we are writing up to against our current
2204a8599bd8SSage Weil  * max_size.  If necessary, tell the MDS we want to write to
2205a8599bd8SSage Weil  * a larger offset.
2206a8599bd8SSage Weil  */
2207a8599bd8SSage Weil static void check_max_size(struct inode *inode, loff_t endoff)
2208a8599bd8SSage Weil {
2209a8599bd8SSage Weil 	struct ceph_inode_info *ci = ceph_inode(inode);
2210a8599bd8SSage Weil 	int check = 0;
2211a8599bd8SSage Weil 
2212a8599bd8SSage Weil 	/* do we need to explicitly request a larger max_size? */
2213be655596SSage Weil 	spin_lock(&ci->i_ceph_lock);
22143871cbb9SYan, Zheng 	if (endoff >= ci->i_max_size && endoff > ci->i_wanted_max_size) {
2215a8599bd8SSage Weil 		dout("write %p at large endoff %llu, req max_size\n",
2216a8599bd8SSage Weil 		     inode, endoff);
2217a8599bd8SSage Weil 		ci->i_wanted_max_size = endoff;
2218a8599bd8SSage Weil 	}
22193871cbb9SYan, Zheng 	/* duplicate ceph_check_caps()'s logic */
22203871cbb9SYan, Zheng 	if (ci->i_auth_cap &&
22213871cbb9SYan, Zheng 	    (ci->i_auth_cap->issued & CEPH_CAP_FILE_WR) &&
22223871cbb9SYan, Zheng 	    ci->i_wanted_max_size > ci->i_max_size &&
22233871cbb9SYan, Zheng 	    ci->i_wanted_max_size > ci->i_requested_max_size)
22243871cbb9SYan, Zheng 		check = 1;
2225be655596SSage Weil 	spin_unlock(&ci->i_ceph_lock);
2226a8599bd8SSage Weil 	if (check)
2227a8599bd8SSage Weil 		ceph_check_caps(ci, CHECK_CAPS_AUTHONLY, NULL);
2228a8599bd8SSage Weil }
2229a8599bd8SSage Weil 
2230a8599bd8SSage Weil /*
2231a8599bd8SSage Weil  * Wait for caps, and take cap references.  If we can't get a WR cap
2232a8599bd8SSage Weil  * due to a small max_size, make sure we check_max_size (and possibly
2233a8599bd8SSage Weil  * ask the mds) so we don't get hung up indefinitely.
2234a8599bd8SSage Weil  */
22353738daa6SYan, Zheng int ceph_get_caps(struct ceph_inode_info *ci, int need, int want,
22363738daa6SYan, Zheng 		  loff_t endoff, int *got, struct page **pinned_page)
2237a8599bd8SSage Weil {
2238a8599bd8SSage Weil 	int check_max, ret, err;
2239a8599bd8SSage Weil 
2240a8599bd8SSage Weil retry:
2241a8599bd8SSage Weil 	if (endoff > 0)
2242a8599bd8SSage Weil 		check_max_size(&ci->vfs_inode, endoff);
2243a8599bd8SSage Weil 	check_max = 0;
2244a8599bd8SSage Weil 	err = 0;
2245a8599bd8SSage Weil 	ret = wait_event_interruptible(ci->i_cap_wq,
22463738daa6SYan, Zheng 				       try_get_cap_refs(ci, need, want, endoff,
22473738daa6SYan, Zheng 							got, pinned_page,
2248a8599bd8SSage Weil 							&check_max, &err));
2249a8599bd8SSage Weil 	if (err)
2250a8599bd8SSage Weil 		ret = err;
2251a8599bd8SSage Weil 	if (check_max)
2252a8599bd8SSage Weil 		goto retry;
2253a8599bd8SSage Weil 	return ret;
2254a8599bd8SSage Weil }
2255a8599bd8SSage Weil 
2256a8599bd8SSage Weil /*
2257a8599bd8SSage Weil  * Take cap refs.  Caller must already know we hold at least one ref
2258a8599bd8SSage Weil  * on the caps in question or we don't know this is safe.
2259a8599bd8SSage Weil  */
2260a8599bd8SSage Weil void ceph_get_cap_refs(struct ceph_inode_info *ci, int caps)
2261a8599bd8SSage Weil {
2262be655596SSage Weil 	spin_lock(&ci->i_ceph_lock);
2263a8599bd8SSage Weil 	__take_cap_refs(ci, caps);
2264be655596SSage Weil 	spin_unlock(&ci->i_ceph_lock);
2265a8599bd8SSage Weil }
2266a8599bd8SSage Weil 
2267a8599bd8SSage Weil /*
2268a8599bd8SSage Weil  * Release cap refs.
2269a8599bd8SSage Weil  *
2270a8599bd8SSage Weil  * If we released the last ref on any given cap, call ceph_check_caps
2271a8599bd8SSage Weil  * to release (or schedule a release).
2272a8599bd8SSage Weil  *
2273a8599bd8SSage Weil  * If we are releasing a WR cap (from a sync write), finalize any affected
2274a8599bd8SSage Weil  * cap_snap, and wake up any waiters.
2275a8599bd8SSage Weil  */
2276a8599bd8SSage Weil void ceph_put_cap_refs(struct ceph_inode_info *ci, int had)
2277a8599bd8SSage Weil {
2278a8599bd8SSage Weil 	struct inode *inode = &ci->vfs_inode;
2279a8599bd8SSage Weil 	int last = 0, put = 0, flushsnaps = 0, wake = 0;
2280a8599bd8SSage Weil 	struct ceph_cap_snap *capsnap;
2281a8599bd8SSage Weil 
2282be655596SSage Weil 	spin_lock(&ci->i_ceph_lock);
2283a8599bd8SSage Weil 	if (had & CEPH_CAP_PIN)
2284a8599bd8SSage Weil 		--ci->i_pin_ref;
2285a8599bd8SSage Weil 	if (had & CEPH_CAP_FILE_RD)
2286a8599bd8SSage Weil 		if (--ci->i_rd_ref == 0)
2287a8599bd8SSage Weil 			last++;
2288a8599bd8SSage Weil 	if (had & CEPH_CAP_FILE_CACHE)
2289a8599bd8SSage Weil 		if (--ci->i_rdcache_ref == 0)
2290a8599bd8SSage Weil 			last++;
2291a8599bd8SSage Weil 	if (had & CEPH_CAP_FILE_BUFFER) {
2292d3d0720dSHenry C Chang 		if (--ci->i_wb_ref == 0) {
2293a8599bd8SSage Weil 			last++;
2294a8599bd8SSage Weil 			put++;
2295a8599bd8SSage Weil 		}
2296d3d0720dSHenry C Chang 		dout("put_cap_refs %p wb %d -> %d (?)\n",
2297d3d0720dSHenry C Chang 		     inode, ci->i_wb_ref+1, ci->i_wb_ref);
2298a8599bd8SSage Weil 	}
2299a8599bd8SSage Weil 	if (had & CEPH_CAP_FILE_WR)
2300a8599bd8SSage Weil 		if (--ci->i_wr_ref == 0) {
2301a8599bd8SSage Weil 			last++;
2302a8599bd8SSage Weil 			if (!list_empty(&ci->i_cap_snaps)) {
2303a8599bd8SSage Weil 				capsnap = list_first_entry(&ci->i_cap_snaps,
2304a8599bd8SSage Weil 						     struct ceph_cap_snap,
2305a8599bd8SSage Weil 						     ci_item);
2306a8599bd8SSage Weil 				if (capsnap->writing) {
2307a8599bd8SSage Weil 					capsnap->writing = 0;
2308a8599bd8SSage Weil 					flushsnaps =
2309a8599bd8SSage Weil 						__ceph_finish_cap_snap(ci,
2310a8599bd8SSage Weil 								       capsnap);
2311a8599bd8SSage Weil 					wake = 1;
2312a8599bd8SSage Weil 				}
2313a8599bd8SSage Weil 			}
2314a8599bd8SSage Weil 		}
2315be655596SSage Weil 	spin_unlock(&ci->i_ceph_lock);
2316a8599bd8SSage Weil 
2317819ccbfaSSage Weil 	dout("put_cap_refs %p had %s%s%s\n", inode, ceph_cap_string(had),
2318819ccbfaSSage Weil 	     last ? " last" : "", put ? " put" : "");
2319a8599bd8SSage Weil 
2320a8599bd8SSage Weil 	if (last && !flushsnaps)
2321a8599bd8SSage Weil 		ceph_check_caps(ci, 0, NULL);
2322a8599bd8SSage Weil 	else if (flushsnaps)
2323a8599bd8SSage Weil 		ceph_flush_snaps(ci);
2324a8599bd8SSage Weil 	if (wake)
232503066f23SYehuda Sadeh 		wake_up_all(&ci->i_cap_wq);
2326a8599bd8SSage Weil 	if (put)
2327a8599bd8SSage Weil 		iput(inode);
2328a8599bd8SSage Weil }
2329a8599bd8SSage Weil 
2330a8599bd8SSage Weil /*
2331a8599bd8SSage Weil  * Release @nr WRBUFFER refs on dirty pages for the given @snapc snap
2332a8599bd8SSage Weil  * context.  Adjust per-snap dirty page accounting as appropriate.
2333a8599bd8SSage Weil  * Once all dirty data for a cap_snap is flushed, flush snapped file
2334a8599bd8SSage Weil  * metadata back to the MDS.  If we dropped the last ref, call
2335a8599bd8SSage Weil  * ceph_check_caps.
2336a8599bd8SSage Weil  */
2337a8599bd8SSage Weil void ceph_put_wrbuffer_cap_refs(struct ceph_inode_info *ci, int nr,
2338a8599bd8SSage Weil 				struct ceph_snap_context *snapc)
2339a8599bd8SSage Weil {
2340a8599bd8SSage Weil 	struct inode *inode = &ci->vfs_inode;
2341a8599bd8SSage Weil 	int last = 0;
2342819ccbfaSSage Weil 	int complete_capsnap = 0;
2343819ccbfaSSage Weil 	int drop_capsnap = 0;
2344a8599bd8SSage Weil 	int found = 0;
2345a8599bd8SSage Weil 	struct ceph_cap_snap *capsnap = NULL;
2346a8599bd8SSage Weil 
2347be655596SSage Weil 	spin_lock(&ci->i_ceph_lock);
2348a8599bd8SSage Weil 	ci->i_wrbuffer_ref -= nr;
2349a8599bd8SSage Weil 	last = !ci->i_wrbuffer_ref;
2350a8599bd8SSage Weil 
2351a8599bd8SSage Weil 	if (ci->i_head_snapc == snapc) {
2352a8599bd8SSage Weil 		ci->i_wrbuffer_ref_head -= nr;
23537d8cb26dSSage Weil 		if (ci->i_wrbuffer_ref_head == 0 &&
23547d8cb26dSSage Weil 		    ci->i_dirty_caps == 0 && ci->i_flushing_caps == 0) {
23557d8cb26dSSage Weil 			BUG_ON(!ci->i_head_snapc);
2356a8599bd8SSage Weil 			ceph_put_snap_context(ci->i_head_snapc);
2357a8599bd8SSage Weil 			ci->i_head_snapc = NULL;
2358a8599bd8SSage Weil 		}
2359a8599bd8SSage Weil 		dout("put_wrbuffer_cap_refs on %p head %d/%d -> %d/%d %s\n",
2360a8599bd8SSage Weil 		     inode,
2361a8599bd8SSage Weil 		     ci->i_wrbuffer_ref+nr, ci->i_wrbuffer_ref_head+nr,
2362a8599bd8SSage Weil 		     ci->i_wrbuffer_ref, ci->i_wrbuffer_ref_head,
2363a8599bd8SSage Weil 		     last ? " LAST" : "");
2364a8599bd8SSage Weil 	} else {
2365a8599bd8SSage Weil 		list_for_each_entry(capsnap, &ci->i_cap_snaps, ci_item) {
2366a8599bd8SSage Weil 			if (capsnap->context == snapc) {
2367a8599bd8SSage Weil 				found = 1;
2368a8599bd8SSage Weil 				break;
2369a8599bd8SSage Weil 			}
2370a8599bd8SSage Weil 		}
2371a8599bd8SSage Weil 		BUG_ON(!found);
2372819ccbfaSSage Weil 		capsnap->dirty_pages -= nr;
2373819ccbfaSSage Weil 		if (capsnap->dirty_pages == 0) {
2374819ccbfaSSage Weil 			complete_capsnap = 1;
2375819ccbfaSSage Weil 			if (capsnap->dirty == 0)
2376819ccbfaSSage Weil 				/* cap writeback completed before we created
2377819ccbfaSSage Weil 				 * the cap_snap; no FLUSHSNAP is needed */
2378819ccbfaSSage Weil 				drop_capsnap = 1;
2379819ccbfaSSage Weil 		}
2380a8599bd8SSage Weil 		dout("put_wrbuffer_cap_refs on %p cap_snap %p "
2381819ccbfaSSage Weil 		     " snap %lld %d/%d -> %d/%d %s%s%s\n",
2382a8599bd8SSage Weil 		     inode, capsnap, capsnap->context->seq,
2383a8599bd8SSage Weil 		     ci->i_wrbuffer_ref+nr, capsnap->dirty_pages + nr,
2384a8599bd8SSage Weil 		     ci->i_wrbuffer_ref, capsnap->dirty_pages,
2385a8599bd8SSage Weil 		     last ? " (wrbuffer last)" : "",
2386819ccbfaSSage Weil 		     complete_capsnap ? " (complete capsnap)" : "",
2387819ccbfaSSage Weil 		     drop_capsnap ? " (drop capsnap)" : "");
2388819ccbfaSSage Weil 		if (drop_capsnap) {
2389819ccbfaSSage Weil 			ceph_put_snap_context(capsnap->context);
2390819ccbfaSSage Weil 			list_del(&capsnap->ci_item);
2391819ccbfaSSage Weil 			list_del(&capsnap->flushing_item);
2392819ccbfaSSage Weil 			ceph_put_cap_snap(capsnap);
2393819ccbfaSSage Weil 		}
2394a8599bd8SSage Weil 	}
2395a8599bd8SSage Weil 
2396be655596SSage Weil 	spin_unlock(&ci->i_ceph_lock);
2397a8599bd8SSage Weil 
2398a8599bd8SSage Weil 	if (last) {
2399a8599bd8SSage Weil 		ceph_check_caps(ci, CHECK_CAPS_AUTHONLY, NULL);
2400a8599bd8SSage Weil 		iput(inode);
2401819ccbfaSSage Weil 	} else if (complete_capsnap) {
2402a8599bd8SSage Weil 		ceph_flush_snaps(ci);
240303066f23SYehuda Sadeh 		wake_up_all(&ci->i_cap_wq);
2404a8599bd8SSage Weil 	}
2405819ccbfaSSage Weil 	if (drop_capsnap)
2406819ccbfaSSage Weil 		iput(inode);
2407a8599bd8SSage Weil }
2408a8599bd8SSage Weil 
2409a8599bd8SSage Weil /*
2410ca20c991SYan, Zheng  * Invalidate unlinked inode's aliases, so we can drop the inode ASAP.
2411ca20c991SYan, Zheng  */
2412ca20c991SYan, Zheng static void invalidate_aliases(struct inode *inode)
2413ca20c991SYan, Zheng {
2414ca20c991SYan, Zheng 	struct dentry *dn, *prev = NULL;
2415ca20c991SYan, Zheng 
2416ca20c991SYan, Zheng 	dout("invalidate_aliases inode %p\n", inode);
2417ca20c991SYan, Zheng 	d_prune_aliases(inode);
2418ca20c991SYan, Zheng 	/*
2419ca20c991SYan, Zheng 	 * For non-directory inode, d_find_alias() only returns
2420fc12c80aSJ. Bruce Fields 	 * hashed dentry. After calling d_invalidate(), the
2421fc12c80aSJ. Bruce Fields 	 * dentry becomes unhashed.
2422ca20c991SYan, Zheng 	 *
2423a8d436f0SYan, Zheng 	 * For directory inode, d_find_alias() can return
2424fc12c80aSJ. Bruce Fields 	 * unhashed dentry. But directory inode should have
2425ca20c991SYan, Zheng 	 * one alias at most.
2426ca20c991SYan, Zheng 	 */
2427ca20c991SYan, Zheng 	while ((dn = d_find_alias(inode))) {
2428ca20c991SYan, Zheng 		if (dn == prev) {
2429ca20c991SYan, Zheng 			dput(dn);
2430ca20c991SYan, Zheng 			break;
2431ca20c991SYan, Zheng 		}
2432a8d436f0SYan, Zheng 		d_invalidate(dn);
2433ca20c991SYan, Zheng 		if (prev)
2434ca20c991SYan, Zheng 			dput(prev);
2435ca20c991SYan, Zheng 		prev = dn;
2436ca20c991SYan, Zheng 	}
2437ca20c991SYan, Zheng 	if (prev)
2438ca20c991SYan, Zheng 		dput(prev);
2439ca20c991SYan, Zheng }
2440ca20c991SYan, Zheng 
2441ca20c991SYan, Zheng /*
2442a8599bd8SSage Weil  * Handle a cap GRANT message from the MDS.  (Note that a GRANT may
2443a8599bd8SSage Weil  * actually be a revocation if it specifies a smaller cap set.)
2444a8599bd8SSage Weil  *
2445be655596SSage Weil  * caller holds s_mutex and i_ceph_lock, we drop both.
2446a8599bd8SSage Weil  */
24472cd698beSYan, Zheng static void handle_cap_grant(struct ceph_mds_client *mdsc,
24482cd698beSYan, Zheng 			     struct inode *inode, struct ceph_mds_caps *grant,
2449fb01d1f8SYan, Zheng 			     u64 inline_version,
2450fb01d1f8SYan, Zheng 			     void *inline_data, int inline_len,
24512cd698beSYan, Zheng 			     struct ceph_buffer *xattr_buf,
2452a8599bd8SSage Weil 			     struct ceph_mds_session *session,
24532cd698beSYan, Zheng 			     struct ceph_cap *cap, int issued)
2454be655596SSage Weil 	__releases(ci->i_ceph_lock)
2455982d6011SYan, Zheng 	__releases(mdsc->snap_rwsem)
2456a8599bd8SSage Weil {
2457a8599bd8SSage Weil 	struct ceph_inode_info *ci = ceph_inode(inode);
2458a8599bd8SSage Weil 	int mds = session->s_mds;
24592f56f56aSSage Weil 	int seq = le32_to_cpu(grant->seq);
2460a8599bd8SSage Weil 	int newcaps = le32_to_cpu(grant->caps);
24612cd698beSYan, Zheng 	int used, wanted, dirty;
2462a8599bd8SSage Weil 	u64 size = le64_to_cpu(grant->size);
2463a8599bd8SSage Weil 	u64 max_size = le64_to_cpu(grant->max_size);
2464a8599bd8SSage Weil 	struct timespec mtime, atime, ctime;
246515637c8bSSage Weil 	int check_caps = 0;
2466ab6c2c3eSFabian Frederick 	bool wake = false;
2467ab6c2c3eSFabian Frederick 	bool writeback = false;
2468ab6c2c3eSFabian Frederick 	bool queue_trunc = false;
2469ab6c2c3eSFabian Frederick 	bool queue_invalidate = false;
2470ab6c2c3eSFabian Frederick 	bool queue_revalidate = false;
2471ab6c2c3eSFabian Frederick 	bool deleted_inode = false;
247231c542a1SYan, Zheng 	bool fill_inline = false;
2473a8599bd8SSage Weil 
24742f56f56aSSage Weil 	dout("handle_cap_grant inode %p cap %p mds%d seq %d %s\n",
24752f56f56aSSage Weil 	     inode, cap, mds, seq, ceph_cap_string(newcaps));
2476a8599bd8SSage Weil 	dout(" size %llu max_size %llu, i_size %llu\n", size, max_size,
2477a8599bd8SSage Weil 		inode->i_size);
2478a8599bd8SSage Weil 
247911df2dfbSYan, Zheng 
248011df2dfbSYan, Zheng 	/*
248111df2dfbSYan, Zheng 	 * auth mds of the inode changed. we received the cap export message,
248211df2dfbSYan, Zheng 	 * but still haven't received the cap import message. handle_cap_export
248311df2dfbSYan, Zheng 	 * updated the new auth MDS' cap.
248411df2dfbSYan, Zheng 	 *
248511df2dfbSYan, Zheng 	 * "ceph_seq_cmp(seq, cap->seq) <= 0" means we are processing a message
248611df2dfbSYan, Zheng 	 * that was sent before the cap import message. So don't remove caps.
248711df2dfbSYan, Zheng 	 */
248811df2dfbSYan, Zheng 	if (ceph_seq_cmp(seq, cap->seq) <= 0) {
248911df2dfbSYan, Zheng 		WARN_ON(cap != ci->i_auth_cap);
249011df2dfbSYan, Zheng 		WARN_ON(cap->cap_id != le64_to_cpu(grant->cap_id));
249111df2dfbSYan, Zheng 		seq = cap->seq;
249211df2dfbSYan, Zheng 		newcaps |= cap->issued;
249311df2dfbSYan, Zheng 	}
249411df2dfbSYan, Zheng 
2495a8599bd8SSage Weil 	/*
2496a8599bd8SSage Weil 	 * If CACHE is being revoked, and we have no dirty buffers,
2497a8599bd8SSage Weil 	 * try to invalidate (once).  (If there are dirty buffers, we
2498a8599bd8SSage Weil 	 * will invalidate _after_ writeback.)
2499a8599bd8SSage Weil 	 */
25003b454c49SSage Weil 	if (((cap->issued & ~newcaps) & CEPH_CAP_FILE_CACHE) &&
25013b454c49SSage Weil 	    (newcaps & CEPH_CAP_FILE_LAZYIO) == 0 &&
2502bcd2cbd1SYehuda Sadeh 	    !ci->i_wrbuffer_ref) {
2503e9075743SLi Wang 		if (try_nonblocking_invalidate(inode)) {
2504a8599bd8SSage Weil 			/* there were locked pages.. invalidate later
2505a8599bd8SSage Weil 			   in a separate thread. */
2506a8599bd8SSage Weil 			if (ci->i_rdcache_revoking != ci->i_rdcache_gen) {
2507ab6c2c3eSFabian Frederick 				queue_invalidate = true;
2508a8599bd8SSage Weil 				ci->i_rdcache_revoking = ci->i_rdcache_gen;
2509a8599bd8SSage Weil 			}
2510a8599bd8SSage Weil 		}
251199ccbd22SMilosz Tanski 
251299ccbd22SMilosz Tanski 		ceph_fscache_invalidate(inode);
2513a8599bd8SSage Weil 	}
2514a8599bd8SSage Weil 
2515a8599bd8SSage Weil 	/* side effects now are allowed */
2516685f9a5dSSage Weil 	cap->cap_gen = session->s_cap_gen;
251711df2dfbSYan, Zheng 	cap->seq = seq;
2518a8599bd8SSage Weil 
2519a8599bd8SSage Weil 	__check_cap_issue(ci, cap, newcaps);
2520a8599bd8SSage Weil 
2521f98a128aSYan, Zheng 	if ((newcaps & CEPH_CAP_AUTH_SHARED) &&
2522f98a128aSYan, Zheng 	    (issued & CEPH_CAP_AUTH_EXCL) == 0) {
2523a8599bd8SSage Weil 		inode->i_mode = le32_to_cpu(grant->mode);
252405cb11c1SEric W. Biederman 		inode->i_uid = make_kuid(&init_user_ns, le32_to_cpu(grant->uid));
252505cb11c1SEric W. Biederman 		inode->i_gid = make_kgid(&init_user_ns, le32_to_cpu(grant->gid));
2526a8599bd8SSage Weil 		dout("%p mode 0%o uid.gid %d.%d\n", inode, inode->i_mode,
2527bd2bae6aSEric W. Biederman 		     from_kuid(&init_user_ns, inode->i_uid),
2528bd2bae6aSEric W. Biederman 		     from_kgid(&init_user_ns, inode->i_gid));
2529a8599bd8SSage Weil 	}
2530a8599bd8SSage Weil 
2531f98a128aSYan, Zheng 	if ((newcaps & CEPH_CAP_AUTH_SHARED) &&
2532f98a128aSYan, Zheng 	    (issued & CEPH_CAP_LINK_EXCL) == 0) {
2533bfe86848SMiklos Szeredi 		set_nlink(inode, le32_to_cpu(grant->nlink));
2534ca20c991SYan, Zheng 		if (inode->i_nlink == 0 &&
2535ca20c991SYan, Zheng 		    (newcaps & (CEPH_CAP_LINK_SHARED | CEPH_CAP_LINK_EXCL)))
2536ab6c2c3eSFabian Frederick 			deleted_inode = true;
2537ca20c991SYan, Zheng 	}
2538a8599bd8SSage Weil 
2539a8599bd8SSage Weil 	if ((issued & CEPH_CAP_XATTR_EXCL) == 0 && grant->xattr_len) {
2540a8599bd8SSage Weil 		int len = le32_to_cpu(grant->xattr_len);
2541a8599bd8SSage Weil 		u64 version = le64_to_cpu(grant->xattr_version);
2542a8599bd8SSage Weil 
2543a8599bd8SSage Weil 		if (version > ci->i_xattrs.version) {
2544a8599bd8SSage Weil 			dout(" got new xattrs v%llu on %p len %d\n",
2545a8599bd8SSage Weil 			     version, inode, len);
2546a8599bd8SSage Weil 			if (ci->i_xattrs.blob)
2547a8599bd8SSage Weil 				ceph_buffer_put(ci->i_xattrs.blob);
2548a8599bd8SSage Weil 			ci->i_xattrs.blob = ceph_buffer_get(xattr_buf);
2549a8599bd8SSage Weil 			ci->i_xattrs.version = version;
25507221fe4cSGuangliang Zhao 			ceph_forget_all_cached_acls(inode);
2551a8599bd8SSage Weil 		}
2552a8599bd8SSage Weil 	}
2553a8599bd8SSage Weil 
255499ccbd22SMilosz Tanski 	/* Do we need to revalidate our fscache cookie. Don't bother on the
255599ccbd22SMilosz Tanski 	 * first cache cap as we already validate at cookie creation time. */
255699ccbd22SMilosz Tanski 	if ((issued & CEPH_CAP_FILE_CACHE) && ci->i_rdcache_gen > 1)
2557ab6c2c3eSFabian Frederick 		queue_revalidate = true;
255899ccbd22SMilosz Tanski 
2559f98a128aSYan, Zheng 	if (newcaps & CEPH_CAP_ANY_RD) {
2560f98a128aSYan, Zheng 		/* ctime/mtime/atime? */
2561a8599bd8SSage Weil 		ceph_decode_timespec(&mtime, &grant->mtime);
2562a8599bd8SSage Weil 		ceph_decode_timespec(&atime, &grant->atime);
2563a8599bd8SSage Weil 		ceph_decode_timespec(&ctime, &grant->ctime);
2564a8599bd8SSage Weil 		ceph_fill_file_time(inode, issued,
2565f98a128aSYan, Zheng 				    le32_to_cpu(grant->time_warp_seq),
2566f98a128aSYan, Zheng 				    &ctime, &mtime, &atime);
2567f98a128aSYan, Zheng 	}
2568a8599bd8SSage Weil 
2569f98a128aSYan, Zheng 	if (newcaps & (CEPH_CAP_ANY_FILE_RD | CEPH_CAP_ANY_FILE_WR)) {
257011df2dfbSYan, Zheng 		/* file layout may have changed */
257111df2dfbSYan, Zheng 		ci->i_layout = grant->layout;
2572f98a128aSYan, Zheng 		/* size/truncate_seq? */
2573f98a128aSYan, Zheng 		queue_trunc = ceph_fill_file_size(inode, issued,
2574f98a128aSYan, Zheng 					le32_to_cpu(grant->truncate_seq),
2575f98a128aSYan, Zheng 					le64_to_cpu(grant->truncate_size),
2576f98a128aSYan, Zheng 					size);
2577a8599bd8SSage Weil 		/* max size increase? */
25785e62ad30SYan, Zheng 		if (ci->i_auth_cap == cap && max_size != ci->i_max_size) {
2579f98a128aSYan, Zheng 			dout("max_size %lld -> %llu\n",
2580f98a128aSYan, Zheng 			     ci->i_max_size, max_size);
2581a8599bd8SSage Weil 			ci->i_max_size = max_size;
2582a8599bd8SSage Weil 			if (max_size >= ci->i_wanted_max_size) {
2583a8599bd8SSage Weil 				ci->i_wanted_max_size = 0;  /* reset */
2584a8599bd8SSage Weil 				ci->i_requested_max_size = 0;
2585a8599bd8SSage Weil 			}
2586ab6c2c3eSFabian Frederick 			wake = true;
2587a8599bd8SSage Weil 		}
2588f98a128aSYan, Zheng 	}
2589a8599bd8SSage Weil 
2590a8599bd8SSage Weil 	/* check cap bits */
2591a8599bd8SSage Weil 	wanted = __ceph_caps_wanted(ci);
2592a8599bd8SSage Weil 	used = __ceph_caps_used(ci);
2593a8599bd8SSage Weil 	dirty = __ceph_caps_dirty(ci);
2594a8599bd8SSage Weil 	dout(" my wanted = %s, used = %s, dirty %s\n",
2595a8599bd8SSage Weil 	     ceph_cap_string(wanted),
2596a8599bd8SSage Weil 	     ceph_cap_string(used),
2597a8599bd8SSage Weil 	     ceph_cap_string(dirty));
2598a8599bd8SSage Weil 	if (wanted != le32_to_cpu(grant->wanted)) {
2599a8599bd8SSage Weil 		dout("mds wanted %s -> %s\n",
2600a8599bd8SSage Weil 		     ceph_cap_string(le32_to_cpu(grant->wanted)),
2601a8599bd8SSage Weil 		     ceph_cap_string(wanted));
2602390306c3SYan, Zheng 		/* imported cap may not have correct mds_wanted */
2603390306c3SYan, Zheng 		if (le32_to_cpu(grant->op) == CEPH_CAP_OP_IMPORT)
2604390306c3SYan, Zheng 			check_caps = 1;
2605a8599bd8SSage Weil 	}
2606a8599bd8SSage Weil 
2607a8599bd8SSage Weil 	/* revocation, grant, or no-op? */
2608a8599bd8SSage Weil 	if (cap->issued & ~newcaps) {
26093b454c49SSage Weil 		int revoking = cap->issued & ~newcaps;
26103b454c49SSage Weil 
26113b454c49SSage Weil 		dout("revocation: %s -> %s (revoking %s)\n",
26123b454c49SSage Weil 		     ceph_cap_string(cap->issued),
26133b454c49SSage Weil 		     ceph_cap_string(newcaps),
26143b454c49SSage Weil 		     ceph_cap_string(revoking));
26150eb6cd49SSage Weil 		if (revoking & used & CEPH_CAP_FILE_BUFFER)
2616ab6c2c3eSFabian Frederick 			writeback = true;  /* initiate writeback; will delay ack */
26173b454c49SSage Weil 		else if (revoking == CEPH_CAP_FILE_CACHE &&
26183b454c49SSage Weil 			 (newcaps & CEPH_CAP_FILE_LAZYIO) == 0 &&
26193b454c49SSage Weil 			 queue_invalidate)
26203b454c49SSage Weil 			; /* do nothing yet, invalidation will be queued */
26213b454c49SSage Weil 		else if (cap == ci->i_auth_cap)
26223b454c49SSage Weil 			check_caps = 1; /* check auth cap only */
26233b454c49SSage Weil 		else
26243b454c49SSage Weil 			check_caps = 2; /* check all caps */
2625a8599bd8SSage Weil 		cap->issued = newcaps;
2626978097c9SSage Weil 		cap->implemented |= newcaps;
2627a8599bd8SSage Weil 	} else if (cap->issued == newcaps) {
2628a8599bd8SSage Weil 		dout("caps unchanged: %s -> %s\n",
2629a8599bd8SSage Weil 		     ceph_cap_string(cap->issued), ceph_cap_string(newcaps));
2630a8599bd8SSage Weil 	} else {
2631a8599bd8SSage Weil 		dout("grant: %s -> %s\n", ceph_cap_string(cap->issued),
2632a8599bd8SSage Weil 		     ceph_cap_string(newcaps));
26336ee6b953SYan, Zheng 		/* non-auth MDS is revoking the newly grant caps ? */
26346ee6b953SYan, Zheng 		if (cap == ci->i_auth_cap &&
26356ee6b953SYan, Zheng 		    __ceph_caps_revoking_other(ci, cap, newcaps))
26366ee6b953SYan, Zheng 		    check_caps = 2;
26376ee6b953SYan, Zheng 
2638a8599bd8SSage Weil 		cap->issued = newcaps;
2639a8599bd8SSage Weil 		cap->implemented |= newcaps; /* add bits only, to
2640a8599bd8SSage Weil 					      * avoid stepping on a
2641a8599bd8SSage Weil 					      * pending revocation */
2642ab6c2c3eSFabian Frederick 		wake = true;
2643a8599bd8SSage Weil 	}
2644978097c9SSage Weil 	BUG_ON(cap->issued & ~cap->implemented);
2645a8599bd8SSage Weil 
264631c542a1SYan, Zheng 	if (inline_version > 0 && inline_version >= ci->i_inline_version) {
264731c542a1SYan, Zheng 		ci->i_inline_version = inline_version;
264831c542a1SYan, Zheng 		if (ci->i_inline_version != CEPH_INLINE_NONE &&
264931c542a1SYan, Zheng 		    (newcaps & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)))
265031c542a1SYan, Zheng 			fill_inline = true;
265131c542a1SYan, Zheng 	}
265231c542a1SYan, Zheng 
2653be655596SSage Weil 	spin_unlock(&ci->i_ceph_lock);
265499ccbd22SMilosz Tanski 
26552cd698beSYan, Zheng 	if (le32_to_cpu(grant->op) == CEPH_CAP_OP_IMPORT) {
26562cd698beSYan, Zheng 		kick_flushing_inode_caps(mdsc, session, inode);
26572cd698beSYan, Zheng 		up_read(&mdsc->snap_rwsem);
26582cd698beSYan, Zheng 		if (newcaps & ~issued)
2659ab6c2c3eSFabian Frederick 			wake = true;
26602cd698beSYan, Zheng 	}
26612cd698beSYan, Zheng 
266231c542a1SYan, Zheng 	if (fill_inline)
266331c542a1SYan, Zheng 		ceph_fill_inline_data(inode, NULL, inline_data, inline_len);
266431c542a1SYan, Zheng 
2665c6bcda6fSYan, Zheng 	if (queue_trunc) {
2666c6bcda6fSYan, Zheng 		ceph_queue_vmtruncate(inode);
2667c6bcda6fSYan, Zheng 		ceph_queue_revalidate(inode);
2668c6bcda6fSYan, Zheng 	} else if (queue_revalidate)
2669c6bcda6fSYan, Zheng 		ceph_queue_revalidate(inode);
2670c6bcda6fSYan, Zheng 
26713c6f6b79SSage Weil 	if (writeback)
2672a8599bd8SSage Weil 		/*
2673a8599bd8SSage Weil 		 * queue inode for writeback: we can't actually call
2674a8599bd8SSage Weil 		 * filemap_write_and_wait, etc. from message handler
2675a8599bd8SSage Weil 		 * context.
2676a8599bd8SSage Weil 		 */
26773c6f6b79SSage Weil 		ceph_queue_writeback(inode);
26783c6f6b79SSage Weil 	if (queue_invalidate)
26793c6f6b79SSage Weil 		ceph_queue_invalidate(inode);
2680ca20c991SYan, Zheng 	if (deleted_inode)
2681ca20c991SYan, Zheng 		invalidate_aliases(inode);
2682a8599bd8SSage Weil 	if (wake)
268303066f23SYehuda Sadeh 		wake_up_all(&ci->i_cap_wq);
268415637c8bSSage Weil 
268515637c8bSSage Weil 	if (check_caps == 1)
268615637c8bSSage Weil 		ceph_check_caps(ci, CHECK_CAPS_NODELAY|CHECK_CAPS_AUTHONLY,
268715637c8bSSage Weil 				session);
268815637c8bSSage Weil 	else if (check_caps == 2)
268915637c8bSSage Weil 		ceph_check_caps(ci, CHECK_CAPS_NODELAY, session);
269015637c8bSSage Weil 	else
269115637c8bSSage Weil 		mutex_unlock(&session->s_mutex);
2692a8599bd8SSage Weil }
2693a8599bd8SSage Weil 
2694a8599bd8SSage Weil /*
2695a8599bd8SSage Weil  * Handle FLUSH_ACK from MDS, indicating that metadata we sent to the
2696a8599bd8SSage Weil  * MDS has been safely committed.
2697a8599bd8SSage Weil  */
26986df058c0SSage Weil static void handle_cap_flush_ack(struct inode *inode, u64 flush_tid,
2699a8599bd8SSage Weil 				 struct ceph_mds_caps *m,
2700a8599bd8SSage Weil 				 struct ceph_mds_session *session,
2701a8599bd8SSage Weil 				 struct ceph_cap *cap)
2702be655596SSage Weil 	__releases(ci->i_ceph_lock)
2703a8599bd8SSage Weil {
2704a8599bd8SSage Weil 	struct ceph_inode_info *ci = ceph_inode(inode);
27053d14c5d2SYehuda Sadeh 	struct ceph_mds_client *mdsc = ceph_sb_to_client(inode->i_sb)->mdsc;
2706a8599bd8SSage Weil 	unsigned seq = le32_to_cpu(m->seq);
2707a8599bd8SSage Weil 	int dirty = le32_to_cpu(m->dirty);
2708a8599bd8SSage Weil 	int cleaned = 0;
2709afcdaea3SSage Weil 	int drop = 0;
2710a8599bd8SSage Weil 	int i;
2711a8599bd8SSage Weil 
2712a8599bd8SSage Weil 	for (i = 0; i < CEPH_CAP_BITS; i++)
2713a8599bd8SSage Weil 		if ((dirty & (1 << i)) &&
27143231300bSYan, Zheng 		    (u16)flush_tid == ci->i_cap_flush_tid[i])
2715a8599bd8SSage Weil 			cleaned |= 1 << i;
2716a8599bd8SSage Weil 
2717a8599bd8SSage Weil 	dout("handle_cap_flush_ack inode %p mds%d seq %d on %s cleaned %s,"
2718a8599bd8SSage Weil 	     " flushing %s -> %s\n",
2719a8599bd8SSage Weil 	     inode, session->s_mds, seq, ceph_cap_string(dirty),
2720a8599bd8SSage Weil 	     ceph_cap_string(cleaned), ceph_cap_string(ci->i_flushing_caps),
2721a8599bd8SSage Weil 	     ceph_cap_string(ci->i_flushing_caps & ~cleaned));
2722a8599bd8SSage Weil 
2723a8599bd8SSage Weil 	if (ci->i_flushing_caps == (ci->i_flushing_caps & ~cleaned))
2724a8599bd8SSage Weil 		goto out;
2725a8599bd8SSage Weil 
2726a8599bd8SSage Weil 	ci->i_flushing_caps &= ~cleaned;
2727a8599bd8SSage Weil 
2728a8599bd8SSage Weil 	spin_lock(&mdsc->cap_dirty_lock);
2729a8599bd8SSage Weil 	if (ci->i_flushing_caps == 0) {
2730a8599bd8SSage Weil 		list_del_init(&ci->i_flushing_item);
2731a8599bd8SSage Weil 		if (!list_empty(&session->s_cap_flushing))
2732a8599bd8SSage Weil 			dout(" mds%d still flushing cap on %p\n",
2733a8599bd8SSage Weil 			     session->s_mds,
2734a8599bd8SSage Weil 			     &list_entry(session->s_cap_flushing.next,
2735a8599bd8SSage Weil 					 struct ceph_inode_info,
2736a8599bd8SSage Weil 					 i_flushing_item)->vfs_inode);
2737a8599bd8SSage Weil 		mdsc->num_cap_flushing--;
273803066f23SYehuda Sadeh 		wake_up_all(&mdsc->cap_flushing_wq);
2739a8599bd8SSage Weil 		dout(" inode %p now !flushing\n", inode);
2740afcdaea3SSage Weil 
2741afcdaea3SSage Weil 		if (ci->i_dirty_caps == 0) {
2742a8599bd8SSage Weil 			dout(" inode %p now clean\n", inode);
2743afcdaea3SSage Weil 			BUG_ON(!list_empty(&ci->i_dirty_item));
2744afcdaea3SSage Weil 			drop = 1;
27457d8cb26dSSage Weil 			if (ci->i_wrbuffer_ref_head == 0) {
27467d8cb26dSSage Weil 				BUG_ON(!ci->i_head_snapc);
27477d8cb26dSSage Weil 				ceph_put_snap_context(ci->i_head_snapc);
27487d8cb26dSSage Weil 				ci->i_head_snapc = NULL;
27497d8cb26dSSage Weil 			}
275076e3b390SSage Weil 		} else {
275176e3b390SSage Weil 			BUG_ON(list_empty(&ci->i_dirty_item));
2752afcdaea3SSage Weil 		}
2753a8599bd8SSage Weil 	}
2754a8599bd8SSage Weil 	spin_unlock(&mdsc->cap_dirty_lock);
275503066f23SYehuda Sadeh 	wake_up_all(&ci->i_cap_wq);
2756a8599bd8SSage Weil 
2757a8599bd8SSage Weil out:
2758be655596SSage Weil 	spin_unlock(&ci->i_ceph_lock);
2759afcdaea3SSage Weil 	if (drop)
2760a8599bd8SSage Weil 		iput(inode);
2761a8599bd8SSage Weil }
2762a8599bd8SSage Weil 
2763a8599bd8SSage Weil /*
2764a8599bd8SSage Weil  * Handle FLUSHSNAP_ACK.  MDS has flushed snap data to disk and we can
2765a8599bd8SSage Weil  * throw away our cap_snap.
2766a8599bd8SSage Weil  *
2767a8599bd8SSage Weil  * Caller hold s_mutex.
2768a8599bd8SSage Weil  */
27696df058c0SSage Weil static void handle_cap_flushsnap_ack(struct inode *inode, u64 flush_tid,
2770a8599bd8SSage Weil 				     struct ceph_mds_caps *m,
2771a8599bd8SSage Weil 				     struct ceph_mds_session *session)
2772a8599bd8SSage Weil {
2773a8599bd8SSage Weil 	struct ceph_inode_info *ci = ceph_inode(inode);
2774a8599bd8SSage Weil 	u64 follows = le64_to_cpu(m->snap_follows);
2775a8599bd8SSage Weil 	struct ceph_cap_snap *capsnap;
2776a8599bd8SSage Weil 	int drop = 0;
2777a8599bd8SSage Weil 
2778a8599bd8SSage Weil 	dout("handle_cap_flushsnap_ack inode %p ci %p mds%d follows %lld\n",
2779a8599bd8SSage Weil 	     inode, ci, session->s_mds, follows);
2780a8599bd8SSage Weil 
2781be655596SSage Weil 	spin_lock(&ci->i_ceph_lock);
2782a8599bd8SSage Weil 	list_for_each_entry(capsnap, &ci->i_cap_snaps, ci_item) {
2783a8599bd8SSage Weil 		if (capsnap->follows == follows) {
2784a8599bd8SSage Weil 			if (capsnap->flush_tid != flush_tid) {
2785a8599bd8SSage Weil 				dout(" cap_snap %p follows %lld tid %lld !="
2786a8599bd8SSage Weil 				     " %lld\n", capsnap, follows,
2787a8599bd8SSage Weil 				     flush_tid, capsnap->flush_tid);
2788a8599bd8SSage Weil 				break;
2789a8599bd8SSage Weil 			}
2790a8599bd8SSage Weil 			WARN_ON(capsnap->dirty_pages || capsnap->writing);
2791819ccbfaSSage Weil 			dout(" removing %p cap_snap %p follows %lld\n",
2792819ccbfaSSage Weil 			     inode, capsnap, follows);
2793a8599bd8SSage Weil 			ceph_put_snap_context(capsnap->context);
2794a8599bd8SSage Weil 			list_del(&capsnap->ci_item);
2795a8599bd8SSage Weil 			list_del(&capsnap->flushing_item);
2796a8599bd8SSage Weil 			ceph_put_cap_snap(capsnap);
2797a8599bd8SSage Weil 			drop = 1;
2798a8599bd8SSage Weil 			break;
2799a8599bd8SSage Weil 		} else {
2800a8599bd8SSage Weil 			dout(" skipping cap_snap %p follows %lld\n",
2801a8599bd8SSage Weil 			     capsnap, capsnap->follows);
2802a8599bd8SSage Weil 		}
2803a8599bd8SSage Weil 	}
2804be655596SSage Weil 	spin_unlock(&ci->i_ceph_lock);
2805a8599bd8SSage Weil 	if (drop)
2806a8599bd8SSage Weil 		iput(inode);
2807a8599bd8SSage Weil }
2808a8599bd8SSage Weil 
2809a8599bd8SSage Weil /*
2810a8599bd8SSage Weil  * Handle TRUNC from MDS, indicating file truncation.
2811a8599bd8SSage Weil  *
2812a8599bd8SSage Weil  * caller hold s_mutex.
2813a8599bd8SSage Weil  */
2814a8599bd8SSage Weil static void handle_cap_trunc(struct inode *inode,
2815a8599bd8SSage Weil 			     struct ceph_mds_caps *trunc,
2816a8599bd8SSage Weil 			     struct ceph_mds_session *session)
2817be655596SSage Weil 	__releases(ci->i_ceph_lock)
2818a8599bd8SSage Weil {
2819a8599bd8SSage Weil 	struct ceph_inode_info *ci = ceph_inode(inode);
2820a8599bd8SSage Weil 	int mds = session->s_mds;
2821a8599bd8SSage Weil 	int seq = le32_to_cpu(trunc->seq);
2822a8599bd8SSage Weil 	u32 truncate_seq = le32_to_cpu(trunc->truncate_seq);
2823a8599bd8SSage Weil 	u64 truncate_size = le64_to_cpu(trunc->truncate_size);
2824a8599bd8SSage Weil 	u64 size = le64_to_cpu(trunc->size);
2825a8599bd8SSage Weil 	int implemented = 0;
2826a8599bd8SSage Weil 	int dirty = __ceph_caps_dirty(ci);
2827a8599bd8SSage Weil 	int issued = __ceph_caps_issued(ceph_inode(inode), &implemented);
2828a8599bd8SSage Weil 	int queue_trunc = 0;
2829a8599bd8SSage Weil 
2830a8599bd8SSage Weil 	issued |= implemented | dirty;
2831a8599bd8SSage Weil 
2832a8599bd8SSage Weil 	dout("handle_cap_trunc inode %p mds%d seq %d to %lld seq %d\n",
2833a8599bd8SSage Weil 	     inode, mds, seq, truncate_size, truncate_seq);
2834a8599bd8SSage Weil 	queue_trunc = ceph_fill_file_size(inode, issued,
2835a8599bd8SSage Weil 					  truncate_seq, truncate_size, size);
2836be655596SSage Weil 	spin_unlock(&ci->i_ceph_lock);
2837a8599bd8SSage Weil 
283899ccbd22SMilosz Tanski 	if (queue_trunc) {
28393c6f6b79SSage Weil 		ceph_queue_vmtruncate(inode);
284099ccbd22SMilosz Tanski 		ceph_fscache_invalidate(inode);
284199ccbd22SMilosz Tanski 	}
2842a8599bd8SSage Weil }
2843a8599bd8SSage Weil 
2844a8599bd8SSage Weil /*
2845a8599bd8SSage Weil  * Handle EXPORT from MDS.  Cap is being migrated _from_ this mds to a
2846a8599bd8SSage Weil  * different one.  If we are the most recent migration we've seen (as
2847a8599bd8SSage Weil  * indicated by mseq), make note of the migrating cap bits for the
2848a8599bd8SSage Weil  * duration (until we see the corresponding IMPORT).
2849a8599bd8SSage Weil  *
2850a8599bd8SSage Weil  * caller holds s_mutex
2851a8599bd8SSage Weil  */
2852a8599bd8SSage Weil static void handle_cap_export(struct inode *inode, struct ceph_mds_caps *ex,
285311df2dfbSYan, Zheng 			      struct ceph_mds_cap_peer *ph,
285411df2dfbSYan, Zheng 			      struct ceph_mds_session *session)
2855a8599bd8SSage Weil {
2856db354052SSage Weil 	struct ceph_mds_client *mdsc = ceph_inode_to_client(inode)->mdsc;
285711df2dfbSYan, Zheng 	struct ceph_mds_session *tsession = NULL;
2858d9df2783SYan, Zheng 	struct ceph_cap *cap, *tcap, *new_cap = NULL;
2859a8599bd8SSage Weil 	struct ceph_inode_info *ci = ceph_inode(inode);
286011df2dfbSYan, Zheng 	u64 t_cap_id;
2861a8599bd8SSage Weil 	unsigned mseq = le32_to_cpu(ex->migrate_seq);
286211df2dfbSYan, Zheng 	unsigned t_seq, t_mseq;
286311df2dfbSYan, Zheng 	int target, issued;
286411df2dfbSYan, Zheng 	int mds = session->s_mds;
2865a8599bd8SSage Weil 
286611df2dfbSYan, Zheng 	if (ph) {
286711df2dfbSYan, Zheng 		t_cap_id = le64_to_cpu(ph->cap_id);
286811df2dfbSYan, Zheng 		t_seq = le32_to_cpu(ph->seq);
286911df2dfbSYan, Zheng 		t_mseq = le32_to_cpu(ph->mseq);
287011df2dfbSYan, Zheng 		target = le32_to_cpu(ph->mds);
287111df2dfbSYan, Zheng 	} else {
287211df2dfbSYan, Zheng 		t_cap_id = t_seq = t_mseq = 0;
287311df2dfbSYan, Zheng 		target = -1;
287411df2dfbSYan, Zheng 	}
2875a8599bd8SSage Weil 
287611df2dfbSYan, Zheng 	dout("handle_cap_export inode %p ci %p mds%d mseq %d target %d\n",
287711df2dfbSYan, Zheng 	     inode, ci, mds, mseq, target);
287811df2dfbSYan, Zheng retry:
2879be655596SSage Weil 	spin_lock(&ci->i_ceph_lock);
288011df2dfbSYan, Zheng 	cap = __get_cap_for_mds(ci, mds);
2881ca665e02SYan, Zheng 	if (!cap || cap->cap_id != le64_to_cpu(ex->cap_id))
288211df2dfbSYan, Zheng 		goto out_unlock;
2883a8599bd8SSage Weil 
288411df2dfbSYan, Zheng 	if (target < 0) {
288511df2dfbSYan, Zheng 		__ceph_remove_cap(cap, false);
288611df2dfbSYan, Zheng 		goto out_unlock;
2887a8599bd8SSage Weil 	}
2888a8599bd8SSage Weil 
2889154f42c2SSage Weil 	/*
289011df2dfbSYan, Zheng 	 * now we know we haven't received the cap import message yet
289111df2dfbSYan, Zheng 	 * because the exported cap still exist.
2892154f42c2SSage Weil 	 */
2893db354052SSage Weil 
289411df2dfbSYan, Zheng 	issued = cap->issued;
289511df2dfbSYan, Zheng 	WARN_ON(issued != cap->implemented);
289611df2dfbSYan, Zheng 
289711df2dfbSYan, Zheng 	tcap = __get_cap_for_mds(ci, target);
289811df2dfbSYan, Zheng 	if (tcap) {
289911df2dfbSYan, Zheng 		/* already have caps from the target */
290011df2dfbSYan, Zheng 		if (tcap->cap_id != t_cap_id ||
290111df2dfbSYan, Zheng 		    ceph_seq_cmp(tcap->seq, t_seq) < 0) {
290211df2dfbSYan, Zheng 			dout(" updating import cap %p mds%d\n", tcap, target);
290311df2dfbSYan, Zheng 			tcap->cap_id = t_cap_id;
290411df2dfbSYan, Zheng 			tcap->seq = t_seq - 1;
290511df2dfbSYan, Zheng 			tcap->issue_seq = t_seq - 1;
290611df2dfbSYan, Zheng 			tcap->mseq = t_mseq;
290711df2dfbSYan, Zheng 			tcap->issued |= issued;
290811df2dfbSYan, Zheng 			tcap->implemented |= issued;
290911df2dfbSYan, Zheng 			if (cap == ci->i_auth_cap)
291011df2dfbSYan, Zheng 				ci->i_auth_cap = tcap;
291111df2dfbSYan, Zheng 			if (ci->i_flushing_caps && ci->i_auth_cap == tcap) {
2912db354052SSage Weil 				spin_lock(&mdsc->cap_dirty_lock);
291311df2dfbSYan, Zheng 				list_move_tail(&ci->i_flushing_item,
291411df2dfbSYan, Zheng 					       &tcap->session->s_cap_flushing);
2915db354052SSage Weil 				spin_unlock(&mdsc->cap_dirty_lock);
2916a8599bd8SSage Weil 			}
2917a8599bd8SSage Weil 		}
291811df2dfbSYan, Zheng 		__ceph_remove_cap(cap, false);
291911df2dfbSYan, Zheng 		goto out_unlock;
2920d9df2783SYan, Zheng 	} else if (tsession) {
292111df2dfbSYan, Zheng 		/* add placeholder for the export tagert */
2922d9df2783SYan, Zheng 		int flag = (cap == ci->i_auth_cap) ? CEPH_CAP_FLAG_AUTH : 0;
292311df2dfbSYan, Zheng 		ceph_add_cap(inode, tsession, t_cap_id, -1, issued, 0,
2924d9df2783SYan, Zheng 			     t_seq - 1, t_mseq, (u64)-1, flag, &new_cap);
2925d9df2783SYan, Zheng 
2926d9df2783SYan, Zheng 		__ceph_remove_cap(cap, false);
2927d9df2783SYan, Zheng 		goto out_unlock;
292811df2dfbSYan, Zheng 	}
2929a8599bd8SSage Weil 
2930be655596SSage Weil 	spin_unlock(&ci->i_ceph_lock);
293111df2dfbSYan, Zheng 	mutex_unlock(&session->s_mutex);
293211df2dfbSYan, Zheng 
293311df2dfbSYan, Zheng 	/* open target session */
293411df2dfbSYan, Zheng 	tsession = ceph_mdsc_open_export_target_session(mdsc, target);
293511df2dfbSYan, Zheng 	if (!IS_ERR(tsession)) {
293611df2dfbSYan, Zheng 		if (mds > target) {
293711df2dfbSYan, Zheng 			mutex_lock(&session->s_mutex);
293811df2dfbSYan, Zheng 			mutex_lock_nested(&tsession->s_mutex,
293911df2dfbSYan, Zheng 					  SINGLE_DEPTH_NESTING);
294011df2dfbSYan, Zheng 		} else {
294111df2dfbSYan, Zheng 			mutex_lock(&tsession->s_mutex);
294211df2dfbSYan, Zheng 			mutex_lock_nested(&session->s_mutex,
294311df2dfbSYan, Zheng 					  SINGLE_DEPTH_NESTING);
294411df2dfbSYan, Zheng 		}
294511df2dfbSYan, Zheng 		ceph_add_cap_releases(mdsc, tsession);
2946d9df2783SYan, Zheng 		new_cap = ceph_get_cap(mdsc, NULL);
294711df2dfbSYan, Zheng 	} else {
294811df2dfbSYan, Zheng 		WARN_ON(1);
294911df2dfbSYan, Zheng 		tsession = NULL;
295011df2dfbSYan, Zheng 		target = -1;
295111df2dfbSYan, Zheng 	}
295211df2dfbSYan, Zheng 	goto retry;
295311df2dfbSYan, Zheng 
295411df2dfbSYan, Zheng out_unlock:
295511df2dfbSYan, Zheng 	spin_unlock(&ci->i_ceph_lock);
295611df2dfbSYan, Zheng 	mutex_unlock(&session->s_mutex);
295711df2dfbSYan, Zheng 	if (tsession) {
295811df2dfbSYan, Zheng 		mutex_unlock(&tsession->s_mutex);
295911df2dfbSYan, Zheng 		ceph_put_mds_session(tsession);
296011df2dfbSYan, Zheng 	}
2961d9df2783SYan, Zheng 	if (new_cap)
2962d9df2783SYan, Zheng 		ceph_put_cap(mdsc, new_cap);
2963a8599bd8SSage Weil }
2964a8599bd8SSage Weil 
2965a8599bd8SSage Weil /*
29662cd698beSYan, Zheng  * Handle cap IMPORT.
2967a8599bd8SSage Weil  *
29682cd698beSYan, Zheng  * caller holds s_mutex. acquires i_ceph_lock
2969a8599bd8SSage Weil  */
2970a8599bd8SSage Weil static void handle_cap_import(struct ceph_mds_client *mdsc,
2971a8599bd8SSage Weil 			      struct inode *inode, struct ceph_mds_caps *im,
29724ee6a914SYan, Zheng 			      struct ceph_mds_cap_peer *ph,
2973a8599bd8SSage Weil 			      struct ceph_mds_session *session,
29742cd698beSYan, Zheng 			      struct ceph_cap **target_cap, int *old_issued)
29752cd698beSYan, Zheng 	__acquires(ci->i_ceph_lock)
2976a8599bd8SSage Weil {
2977a8599bd8SSage Weil 	struct ceph_inode_info *ci = ceph_inode(inode);
29782cd698beSYan, Zheng 	struct ceph_cap *cap, *ocap, *new_cap = NULL;
2979a8599bd8SSage Weil 	int mds = session->s_mds;
29802cd698beSYan, Zheng 	int issued;
29812cd698beSYan, Zheng 	unsigned caps = le32_to_cpu(im->caps);
2982a8599bd8SSage Weil 	unsigned wanted = le32_to_cpu(im->wanted);
2983a8599bd8SSage Weil 	unsigned seq = le32_to_cpu(im->seq);
2984a8599bd8SSage Weil 	unsigned mseq = le32_to_cpu(im->migrate_seq);
2985a8599bd8SSage Weil 	u64 realmino = le64_to_cpu(im->realm);
2986a8599bd8SSage Weil 	u64 cap_id = le64_to_cpu(im->cap_id);
29874ee6a914SYan, Zheng 	u64 p_cap_id;
29884ee6a914SYan, Zheng 	int peer;
2989a8599bd8SSage Weil 
29904ee6a914SYan, Zheng 	if (ph) {
29914ee6a914SYan, Zheng 		p_cap_id = le64_to_cpu(ph->cap_id);
29924ee6a914SYan, Zheng 		peer = le32_to_cpu(ph->mds);
2993a8599bd8SSage Weil 	} else {
29944ee6a914SYan, Zheng 		p_cap_id = 0;
29954ee6a914SYan, Zheng 		peer = -1;
2996a8599bd8SSage Weil 	}
2997a8599bd8SSage Weil 
29984ee6a914SYan, Zheng 	dout("handle_cap_import inode %p ci %p mds%d mseq %d peer %d\n",
29994ee6a914SYan, Zheng 	     inode, ci, mds, mseq, peer);
30004ee6a914SYan, Zheng 
3001d9df2783SYan, Zheng retry:
30024ee6a914SYan, Zheng 	spin_lock(&ci->i_ceph_lock);
3003d9df2783SYan, Zheng 	cap = __get_cap_for_mds(ci, mds);
3004d9df2783SYan, Zheng 	if (!cap) {
3005d9df2783SYan, Zheng 		if (!new_cap) {
3006d9df2783SYan, Zheng 			spin_unlock(&ci->i_ceph_lock);
3007d9df2783SYan, Zheng 			new_cap = ceph_get_cap(mdsc, NULL);
3008d9df2783SYan, Zheng 			goto retry;
3009d9df2783SYan, Zheng 		}
30102cd698beSYan, Zheng 		cap = new_cap;
30112cd698beSYan, Zheng 	} else {
30122cd698beSYan, Zheng 		if (new_cap) {
30132cd698beSYan, Zheng 			ceph_put_cap(mdsc, new_cap);
30142cd698beSYan, Zheng 			new_cap = NULL;
30152cd698beSYan, Zheng 		}
3016d9df2783SYan, Zheng 	}
3017d9df2783SYan, Zheng 
30182cd698beSYan, Zheng 	__ceph_caps_issued(ci, &issued);
30192cd698beSYan, Zheng 	issued |= __ceph_caps_dirty(ci);
30202cd698beSYan, Zheng 
30212cd698beSYan, Zheng 	ceph_add_cap(inode, session, cap_id, -1, caps, wanted, seq, mseq,
3022d9df2783SYan, Zheng 		     realmino, CEPH_CAP_FLAG_AUTH, &new_cap);
3023d9df2783SYan, Zheng 
30242cd698beSYan, Zheng 	ocap = peer >= 0 ? __get_cap_for_mds(ci, peer) : NULL;
30252cd698beSYan, Zheng 	if (ocap && ocap->cap_id == p_cap_id) {
30264ee6a914SYan, Zheng 		dout(" remove export cap %p mds%d flags %d\n",
30272cd698beSYan, Zheng 		     ocap, peer, ph->flags);
30284ee6a914SYan, Zheng 		if ((ph->flags & CEPH_CAP_FLAG_AUTH) &&
30292cd698beSYan, Zheng 		    (ocap->seq != le32_to_cpu(ph->seq) ||
30302cd698beSYan, Zheng 		     ocap->mseq != le32_to_cpu(ph->mseq))) {
30314ee6a914SYan, Zheng 			pr_err("handle_cap_import: mismatched seq/mseq: "
30324ee6a914SYan, Zheng 			       "ino (%llx.%llx) mds%d seq %d mseq %d "
30334ee6a914SYan, Zheng 			       "importer mds%d has peer seq %d mseq %d\n",
30342cd698beSYan, Zheng 			       ceph_vinop(inode), peer, ocap->seq,
30352cd698beSYan, Zheng 			       ocap->mseq, mds, le32_to_cpu(ph->seq),
30364ee6a914SYan, Zheng 			       le32_to_cpu(ph->mseq));
30374ee6a914SYan, Zheng 		}
30382cd698beSYan, Zheng 		__ceph_remove_cap(ocap, (ph->flags & CEPH_CAP_FLAG_RELEASE));
30394ee6a914SYan, Zheng 	}
30404ee6a914SYan, Zheng 
30414ee6a914SYan, Zheng 	/* make sure we re-request max_size, if necessary */
30424ee6a914SYan, Zheng 	ci->i_wanted_max_size = 0;
30434ee6a914SYan, Zheng 	ci->i_requested_max_size = 0;
30444ee6a914SYan, Zheng 
30452cd698beSYan, Zheng 	*old_issued = issued;
30462cd698beSYan, Zheng 	*target_cap = cap;
3047a8599bd8SSage Weil }
3048a8599bd8SSage Weil 
3049a8599bd8SSage Weil /*
3050a8599bd8SSage Weil  * Handle a caps message from the MDS.
3051a8599bd8SSage Weil  *
3052a8599bd8SSage Weil  * Identify the appropriate session, inode, and call the right handler
3053a8599bd8SSage Weil  * based on the cap op.
3054a8599bd8SSage Weil  */
3055a8599bd8SSage Weil void ceph_handle_caps(struct ceph_mds_session *session,
3056a8599bd8SSage Weil 		      struct ceph_msg *msg)
3057a8599bd8SSage Weil {
3058a8599bd8SSage Weil 	struct ceph_mds_client *mdsc = session->s_mdsc;
30593d14c5d2SYehuda Sadeh 	struct super_block *sb = mdsc->fsc->sb;
3060a8599bd8SSage Weil 	struct inode *inode;
3061be655596SSage Weil 	struct ceph_inode_info *ci;
3062a8599bd8SSage Weil 	struct ceph_cap *cap;
3063a8599bd8SSage Weil 	struct ceph_mds_caps *h;
30644ee6a914SYan, Zheng 	struct ceph_mds_cap_peer *peer = NULL;
3065982d6011SYan, Zheng 	struct ceph_snap_realm *realm;
30662600d2ddSSage Weil 	int mds = session->s_mds;
30672cd698beSYan, Zheng 	int op, issued;
30683d7ded4dSSage Weil 	u32 seq, mseq;
3069a8599bd8SSage Weil 	struct ceph_vino vino;
3070a8599bd8SSage Weil 	u64 cap_id;
3071a8599bd8SSage Weil 	u64 size, max_size;
30726df058c0SSage Weil 	u64 tid;
3073fb01d1f8SYan, Zheng 	u64 inline_version = 0;
3074fb01d1f8SYan, Zheng 	void *inline_data = NULL;
3075fb01d1f8SYan, Zheng 	u32  inline_len = 0;
307670edb55bSSage Weil 	void *snaptrace;
3077ce1fbc8dSSage Weil 	size_t snaptrace_len;
3078fb01d1f8SYan, Zheng 	void *p, *end;
3079a8599bd8SSage Weil 
3080a8599bd8SSage Weil 	dout("handle_caps from mds%d\n", mds);
3081a8599bd8SSage Weil 
3082a8599bd8SSage Weil 	/* decode */
30834ee6a914SYan, Zheng 	end = msg->front.iov_base + msg->front.iov_len;
30846df058c0SSage Weil 	tid = le64_to_cpu(msg->hdr.tid);
3085a8599bd8SSage Weil 	if (msg->front.iov_len < sizeof(*h))
3086a8599bd8SSage Weil 		goto bad;
3087a8599bd8SSage Weil 	h = msg->front.iov_base;
3088a8599bd8SSage Weil 	op = le32_to_cpu(h->op);
3089a8599bd8SSage Weil 	vino.ino = le64_to_cpu(h->ino);
3090a8599bd8SSage Weil 	vino.snap = CEPH_NOSNAP;
3091a8599bd8SSage Weil 	cap_id = le64_to_cpu(h->cap_id);
3092a8599bd8SSage Weil 	seq = le32_to_cpu(h->seq);
30933d7ded4dSSage Weil 	mseq = le32_to_cpu(h->migrate_seq);
3094a8599bd8SSage Weil 	size = le64_to_cpu(h->size);
3095a8599bd8SSage Weil 	max_size = le64_to_cpu(h->max_size);
3096a8599bd8SSage Weil 
3097ce1fbc8dSSage Weil 	snaptrace = h + 1;
3098ce1fbc8dSSage Weil 	snaptrace_len = le32_to_cpu(h->snap_trace_len);
3099fb01d1f8SYan, Zheng 	p = snaptrace + snaptrace_len;
3100ce1fbc8dSSage Weil 
3101ce1fbc8dSSage Weil 	if (le16_to_cpu(msg->hdr.version) >= 2) {
3102fb01d1f8SYan, Zheng 		u32 flock_len;
3103ce1fbc8dSSage Weil 		ceph_decode_32_safe(&p, end, flock_len, bad);
31044ee6a914SYan, Zheng 		if (p + flock_len > end)
31054ee6a914SYan, Zheng 			goto bad;
3106fb01d1f8SYan, Zheng 		p += flock_len;
3107ce1fbc8dSSage Weil 	}
3108ce1fbc8dSSage Weil 
31094ee6a914SYan, Zheng 	if (le16_to_cpu(msg->hdr.version) >= 3) {
31104ee6a914SYan, Zheng 		if (op == CEPH_CAP_OP_IMPORT) {
31114ee6a914SYan, Zheng 			if (p + sizeof(*peer) > end)
31124ee6a914SYan, Zheng 				goto bad;
31134ee6a914SYan, Zheng 			peer = p;
3114fb01d1f8SYan, Zheng 			p += sizeof(*peer);
311511df2dfbSYan, Zheng 		} else if (op == CEPH_CAP_OP_EXPORT) {
311611df2dfbSYan, Zheng 			/* recorded in unused fields */
311711df2dfbSYan, Zheng 			peer = (void *)&h->size;
31184ee6a914SYan, Zheng 		}
31194ee6a914SYan, Zheng 	}
31204ee6a914SYan, Zheng 
3121fb01d1f8SYan, Zheng 	if (le16_to_cpu(msg->hdr.version) >= 4) {
3122fb01d1f8SYan, Zheng 		ceph_decode_64_safe(&p, end, inline_version, bad);
3123fb01d1f8SYan, Zheng 		ceph_decode_32_safe(&p, end, inline_len, bad);
3124fb01d1f8SYan, Zheng 		if (p + inline_len > end)
3125fb01d1f8SYan, Zheng 			goto bad;
3126fb01d1f8SYan, Zheng 		inline_data = p;
3127fb01d1f8SYan, Zheng 		p += inline_len;
3128fb01d1f8SYan, Zheng 	}
3129fb01d1f8SYan, Zheng 
31306cd3bcadSYan, Zheng 	/* lookup ino */
31316cd3bcadSYan, Zheng 	inode = ceph_find_inode(sb, vino);
31326cd3bcadSYan, Zheng 	ci = ceph_inode(inode);
31336cd3bcadSYan, Zheng 	dout(" op %s ino %llx.%llx inode %p\n", ceph_cap_op_name(op), vino.ino,
31346cd3bcadSYan, Zheng 	     vino.snap, inode);
31356cd3bcadSYan, Zheng 
3136a8599bd8SSage Weil 	mutex_lock(&session->s_mutex);
3137a8599bd8SSage Weil 	session->s_seq++;
3138a8599bd8SSage Weil 	dout(" mds%d seq %lld cap seq %u\n", session->s_mds, session->s_seq,
3139a8599bd8SSage Weil 	     (unsigned)seq);
3140a8599bd8SSage Weil 
314166f58691SYan, Zheng 	if (op == CEPH_CAP_OP_IMPORT)
314266f58691SYan, Zheng 		ceph_add_cap_releases(mdsc, session);
314366f58691SYan, Zheng 
3144a8599bd8SSage Weil 	if (!inode) {
3145a8599bd8SSage Weil 		dout(" i don't have ino %llx\n", vino.ino);
31463d7ded4dSSage Weil 
3147a096b09aSYan, Zheng 		if (op == CEPH_CAP_OP_IMPORT) {
3148a096b09aSYan, Zheng 			spin_lock(&session->s_cap_lock);
31493d7ded4dSSage Weil 			__queue_cap_release(session, vino.ino, cap_id,
31503d7ded4dSSage Weil 					    mseq, seq);
3151a096b09aSYan, Zheng 			spin_unlock(&session->s_cap_lock);
3152a096b09aSYan, Zheng 		}
315321b559deSGreg Farnum 		goto flush_cap_releases;
3154a8599bd8SSage Weil 	}
3155a8599bd8SSage Weil 
3156a8599bd8SSage Weil 	/* these will work even if we don't have a cap yet */
3157a8599bd8SSage Weil 	switch (op) {
3158a8599bd8SSage Weil 	case CEPH_CAP_OP_FLUSHSNAP_ACK:
31596df058c0SSage Weil 		handle_cap_flushsnap_ack(inode, tid, h, session);
3160a8599bd8SSage Weil 		goto done;
3161a8599bd8SSage Weil 
3162a8599bd8SSage Weil 	case CEPH_CAP_OP_EXPORT:
316311df2dfbSYan, Zheng 		handle_cap_export(inode, h, peer, session);
316411df2dfbSYan, Zheng 		goto done_unlocked;
3165a8599bd8SSage Weil 
3166a8599bd8SSage Weil 	case CEPH_CAP_OP_IMPORT:
3167982d6011SYan, Zheng 		realm = NULL;
3168982d6011SYan, Zheng 		if (snaptrace_len) {
3169982d6011SYan, Zheng 			down_write(&mdsc->snap_rwsem);
3170982d6011SYan, Zheng 			ceph_update_snap_trace(mdsc, snaptrace,
3171982d6011SYan, Zheng 					       snaptrace + snaptrace_len,
3172982d6011SYan, Zheng 					       false, &realm);
3173982d6011SYan, Zheng 			downgrade_write(&mdsc->snap_rwsem);
3174982d6011SYan, Zheng 		} else {
3175982d6011SYan, Zheng 			down_read(&mdsc->snap_rwsem);
3176982d6011SYan, Zheng 		}
31774ee6a914SYan, Zheng 		handle_cap_import(mdsc, inode, h, peer, session,
31782cd698beSYan, Zheng 				  &cap, &issued);
3179982d6011SYan, Zheng 		handle_cap_grant(mdsc, inode, h,
3180fb01d1f8SYan, Zheng 				 inline_version, inline_data, inline_len,
31812cd698beSYan, Zheng 				 msg->middle, session, cap, issued);
3182982d6011SYan, Zheng 		if (realm)
3183982d6011SYan, Zheng 			ceph_put_snap_realm(mdsc, realm);
31842cd698beSYan, Zheng 		goto done_unlocked;
3185a8599bd8SSage Weil 	}
3186a8599bd8SSage Weil 
3187a8599bd8SSage Weil 	/* the rest require a cap */
3188be655596SSage Weil 	spin_lock(&ci->i_ceph_lock);
3189a8599bd8SSage Weil 	cap = __get_cap_for_mds(ceph_inode(inode), mds);
3190a8599bd8SSage Weil 	if (!cap) {
31919dbd412fSSage Weil 		dout(" no cap on %p ino %llx.%llx from mds%d\n",
3192a8599bd8SSage Weil 		     inode, ceph_ino(inode), ceph_snap(inode), mds);
3193be655596SSage Weil 		spin_unlock(&ci->i_ceph_lock);
319421b559deSGreg Farnum 		goto flush_cap_releases;
3195a8599bd8SSage Weil 	}
3196a8599bd8SSage Weil 
3197be655596SSage Weil 	/* note that each of these drops i_ceph_lock for us */
3198a8599bd8SSage Weil 	switch (op) {
3199a8599bd8SSage Weil 	case CEPH_CAP_OP_REVOKE:
3200a8599bd8SSage Weil 	case CEPH_CAP_OP_GRANT:
32012cd698beSYan, Zheng 		__ceph_caps_issued(ci, &issued);
32022cd698beSYan, Zheng 		issued |= __ceph_caps_dirty(ci);
3203982d6011SYan, Zheng 		handle_cap_grant(mdsc, inode, h,
3204fb01d1f8SYan, Zheng 				 inline_version, inline_data, inline_len,
3205fb01d1f8SYan, Zheng 				 msg->middle, session, cap, issued);
320615637c8bSSage Weil 		goto done_unlocked;
3207a8599bd8SSage Weil 
3208a8599bd8SSage Weil 	case CEPH_CAP_OP_FLUSH_ACK:
32096df058c0SSage Weil 		handle_cap_flush_ack(inode, tid, h, session, cap);
3210a8599bd8SSage Weil 		break;
3211a8599bd8SSage Weil 
3212a8599bd8SSage Weil 	case CEPH_CAP_OP_TRUNC:
3213a8599bd8SSage Weil 		handle_cap_trunc(inode, h, session);
3214a8599bd8SSage Weil 		break;
3215a8599bd8SSage Weil 
3216a8599bd8SSage Weil 	default:
3217be655596SSage Weil 		spin_unlock(&ci->i_ceph_lock);
3218a8599bd8SSage Weil 		pr_err("ceph_handle_caps: unknown cap op %d %s\n", op,
3219a8599bd8SSage Weil 		       ceph_cap_op_name(op));
3220a8599bd8SSage Weil 	}
3221a8599bd8SSage Weil 
322221b559deSGreg Farnum 	goto done;
322321b559deSGreg Farnum 
322421b559deSGreg Farnum flush_cap_releases:
322521b559deSGreg Farnum 	/*
322621b559deSGreg Farnum 	 * send any full release message to try to move things
322721b559deSGreg Farnum 	 * along for the mds (who clearly thinks we still have this
322821b559deSGreg Farnum 	 * cap).
322921b559deSGreg Farnum 	 */
323021b559deSGreg Farnum 	ceph_add_cap_releases(mdsc, session);
323121b559deSGreg Farnum 	ceph_send_cap_releases(mdsc, session);
323221b559deSGreg Farnum 
3233a8599bd8SSage Weil done:
3234a8599bd8SSage Weil 	mutex_unlock(&session->s_mutex);
323515637c8bSSage Weil done_unlocked:
3236a8599bd8SSage Weil 	iput(inode);
3237a8599bd8SSage Weil 	return;
3238a8599bd8SSage Weil 
3239a8599bd8SSage Weil bad:
3240a8599bd8SSage Weil 	pr_err("ceph_handle_caps: corrupt message\n");
32419ec7cab1SSage Weil 	ceph_msg_dump(msg);
3242a8599bd8SSage Weil 	return;
3243a8599bd8SSage Weil }
3244a8599bd8SSage Weil 
3245a8599bd8SSage Weil /*
3246a8599bd8SSage Weil  * Delayed work handler to process end of delayed cap release LRU list.
3247a8599bd8SSage Weil  */
3248afcdaea3SSage Weil void ceph_check_delayed_caps(struct ceph_mds_client *mdsc)
3249a8599bd8SSage Weil {
3250a8599bd8SSage Weil 	struct ceph_inode_info *ci;
3251a8599bd8SSage Weil 	int flags = CHECK_CAPS_NODELAY;
3252a8599bd8SSage Weil 
3253a8599bd8SSage Weil 	dout("check_delayed_caps\n");
3254a8599bd8SSage Weil 	while (1) {
3255a8599bd8SSage Weil 		spin_lock(&mdsc->cap_delay_lock);
3256a8599bd8SSage Weil 		if (list_empty(&mdsc->cap_delay_list))
3257a8599bd8SSage Weil 			break;
3258a8599bd8SSage Weil 		ci = list_first_entry(&mdsc->cap_delay_list,
3259a8599bd8SSage Weil 				      struct ceph_inode_info,
3260a8599bd8SSage Weil 				      i_cap_delay_list);
3261a8599bd8SSage Weil 		if ((ci->i_ceph_flags & CEPH_I_FLUSH) == 0 &&
3262a8599bd8SSage Weil 		    time_before(jiffies, ci->i_hold_caps_max))
3263a8599bd8SSage Weil 			break;
3264a8599bd8SSage Weil 		list_del_init(&ci->i_cap_delay_list);
3265a8599bd8SSage Weil 		spin_unlock(&mdsc->cap_delay_lock);
3266a8599bd8SSage Weil 		dout("check_delayed_caps on %p\n", &ci->vfs_inode);
3267a8599bd8SSage Weil 		ceph_check_caps(ci, flags, NULL);
3268a8599bd8SSage Weil 	}
3269a8599bd8SSage Weil 	spin_unlock(&mdsc->cap_delay_lock);
3270a8599bd8SSage Weil }
3271a8599bd8SSage Weil 
3272a8599bd8SSage Weil /*
3273afcdaea3SSage Weil  * Flush all dirty caps to the mds
3274afcdaea3SSage Weil  */
3275afcdaea3SSage Weil void ceph_flush_dirty_caps(struct ceph_mds_client *mdsc)
3276afcdaea3SSage Weil {
3277db354052SSage Weil 	struct ceph_inode_info *ci;
3278db354052SSage Weil 	struct inode *inode;
3279afcdaea3SSage Weil 
3280afcdaea3SSage Weil 	dout("flush_dirty_caps\n");
3281afcdaea3SSage Weil 	spin_lock(&mdsc->cap_dirty_lock);
3282db354052SSage Weil 	while (!list_empty(&mdsc->cap_dirty)) {
3283db354052SSage Weil 		ci = list_first_entry(&mdsc->cap_dirty, struct ceph_inode_info,
3284afcdaea3SSage Weil 				      i_dirty_item);
328570b666c3SSage Weil 		inode = &ci->vfs_inode;
328670b666c3SSage Weil 		ihold(inode);
3287db354052SSage Weil 		dout("flush_dirty_caps %p\n", inode);
3288afcdaea3SSage Weil 		spin_unlock(&mdsc->cap_dirty_lock);
328970b666c3SSage Weil 		ceph_check_caps(ci, CHECK_CAPS_NODELAY|CHECK_CAPS_FLUSH, NULL);
3290afcdaea3SSage Weil 		iput(inode);
3291afcdaea3SSage Weil 		spin_lock(&mdsc->cap_dirty_lock);
3292afcdaea3SSage Weil 	}
3293afcdaea3SSage Weil 	spin_unlock(&mdsc->cap_dirty_lock);
3294db354052SSage Weil 	dout("flush_dirty_caps done\n");
3295afcdaea3SSage Weil }
3296afcdaea3SSage Weil 
3297afcdaea3SSage Weil /*
3298a8599bd8SSage Weil  * Drop open file reference.  If we were the last open file,
3299a8599bd8SSage Weil  * we may need to release capabilities to the MDS (or schedule
3300a8599bd8SSage Weil  * their delayed release).
3301a8599bd8SSage Weil  */
3302a8599bd8SSage Weil void ceph_put_fmode(struct ceph_inode_info *ci, int fmode)
3303a8599bd8SSage Weil {
3304a8599bd8SSage Weil 	struct inode *inode = &ci->vfs_inode;
3305a8599bd8SSage Weil 	int last = 0;
3306a8599bd8SSage Weil 
3307be655596SSage Weil 	spin_lock(&ci->i_ceph_lock);
3308a8599bd8SSage Weil 	dout("put_fmode %p fmode %d %d -> %d\n", inode, fmode,
3309a8599bd8SSage Weil 	     ci->i_nr_by_mode[fmode], ci->i_nr_by_mode[fmode]-1);
3310a8599bd8SSage Weil 	BUG_ON(ci->i_nr_by_mode[fmode] == 0);
3311a8599bd8SSage Weil 	if (--ci->i_nr_by_mode[fmode] == 0)
3312a8599bd8SSage Weil 		last++;
3313be655596SSage Weil 	spin_unlock(&ci->i_ceph_lock);
3314a8599bd8SSage Weil 
3315a8599bd8SSage Weil 	if (last && ci->i_vino.snap == CEPH_NOSNAP)
3316a8599bd8SSage Weil 		ceph_check_caps(ci, 0, NULL);
3317a8599bd8SSage Weil }
3318a8599bd8SSage Weil 
3319a8599bd8SSage Weil /*
3320a8599bd8SSage Weil  * Helpers for embedding cap and dentry lease releases into mds
3321a8599bd8SSage Weil  * requests.
3322a8599bd8SSage Weil  *
3323a8599bd8SSage Weil  * @force is used by dentry_release (below) to force inclusion of a
3324a8599bd8SSage Weil  * record for the directory inode, even when there aren't any caps to
3325a8599bd8SSage Weil  * drop.
3326a8599bd8SSage Weil  */
3327a8599bd8SSage Weil int ceph_encode_inode_release(void **p, struct inode *inode,
3328a8599bd8SSage Weil 			      int mds, int drop, int unless, int force)
3329a8599bd8SSage Weil {
3330a8599bd8SSage Weil 	struct ceph_inode_info *ci = ceph_inode(inode);
3331a8599bd8SSage Weil 	struct ceph_cap *cap;
3332a8599bd8SSage Weil 	struct ceph_mds_request_release *rel = *p;
3333ec97f88bSSage Weil 	int used, dirty;
3334a8599bd8SSage Weil 	int ret = 0;
3335a8599bd8SSage Weil 
3336be655596SSage Weil 	spin_lock(&ci->i_ceph_lock);
3337916623daSSage Weil 	used = __ceph_caps_used(ci);
3338ec97f88bSSage Weil 	dirty = __ceph_caps_dirty(ci);
3339916623daSSage Weil 
3340ec97f88bSSage Weil 	dout("encode_inode_release %p mds%d used|dirty %s drop %s unless %s\n",
3341ec97f88bSSage Weil 	     inode, mds, ceph_cap_string(used|dirty), ceph_cap_string(drop),
3342916623daSSage Weil 	     ceph_cap_string(unless));
3343916623daSSage Weil 
3344ec97f88bSSage Weil 	/* only drop unused, clean caps */
3345ec97f88bSSage Weil 	drop &= ~(used | dirty);
3346916623daSSage Weil 
3347a8599bd8SSage Weil 	cap = __get_cap_for_mds(ci, mds);
3348a8599bd8SSage Weil 	if (cap && __cap_is_valid(cap)) {
3349a8599bd8SSage Weil 		if (force ||
3350a8599bd8SSage Weil 		    ((cap->issued & drop) &&
3351a8599bd8SSage Weil 		     (cap->issued & unless) == 0)) {
3352a8599bd8SSage Weil 			if ((cap->issued & drop) &&
3353a8599bd8SSage Weil 			    (cap->issued & unless) == 0) {
3354bb137f84SYan, Zheng 				int wanted = __ceph_caps_wanted(ci);
3355bb137f84SYan, Zheng 				if ((ci->i_ceph_flags & CEPH_I_NODELAY) == 0)
3356bb137f84SYan, Zheng 					wanted |= cap->mds_wanted;
3357bb137f84SYan, Zheng 				dout("encode_inode_release %p cap %p "
3358bb137f84SYan, Zheng 				     "%s -> %s, wanted %s -> %s\n", inode, cap,
3359a8599bd8SSage Weil 				     ceph_cap_string(cap->issued),
3360bb137f84SYan, Zheng 				     ceph_cap_string(cap->issued & ~drop),
3361bb137f84SYan, Zheng 				     ceph_cap_string(cap->mds_wanted),
3362bb137f84SYan, Zheng 				     ceph_cap_string(wanted));
3363bb137f84SYan, Zheng 
3364a8599bd8SSage Weil 				cap->issued &= ~drop;
3365a8599bd8SSage Weil 				cap->implemented &= ~drop;
3366bb137f84SYan, Zheng 				cap->mds_wanted = wanted;
3367a8599bd8SSage Weil 			} else {
3368a8599bd8SSage Weil 				dout("encode_inode_release %p cap %p %s"
3369a8599bd8SSage Weil 				     " (force)\n", inode, cap,
3370a8599bd8SSage Weil 				     ceph_cap_string(cap->issued));
3371a8599bd8SSage Weil 			}
3372a8599bd8SSage Weil 
3373a8599bd8SSage Weil 			rel->ino = cpu_to_le64(ceph_ino(inode));
3374a8599bd8SSage Weil 			rel->cap_id = cpu_to_le64(cap->cap_id);
3375a8599bd8SSage Weil 			rel->seq = cpu_to_le32(cap->seq);
337608a0f24eSHimangi Saraogi 			rel->issue_seq = cpu_to_le32(cap->issue_seq);
3377a8599bd8SSage Weil 			rel->mseq = cpu_to_le32(cap->mseq);
3378fd7b95cdSYan, Zheng 			rel->caps = cpu_to_le32(cap->implemented);
3379a8599bd8SSage Weil 			rel->wanted = cpu_to_le32(cap->mds_wanted);
3380a8599bd8SSage Weil 			rel->dname_len = 0;
3381a8599bd8SSage Weil 			rel->dname_seq = 0;
3382a8599bd8SSage Weil 			*p += sizeof(*rel);
3383a8599bd8SSage Weil 			ret = 1;
3384a8599bd8SSage Weil 		} else {
3385a8599bd8SSage Weil 			dout("encode_inode_release %p cap %p %s\n",
3386a8599bd8SSage Weil 			     inode, cap, ceph_cap_string(cap->issued));
3387a8599bd8SSage Weil 		}
3388a8599bd8SSage Weil 	}
3389be655596SSage Weil 	spin_unlock(&ci->i_ceph_lock);
3390a8599bd8SSage Weil 	return ret;
3391a8599bd8SSage Weil }
3392a8599bd8SSage Weil 
3393a8599bd8SSage Weil int ceph_encode_dentry_release(void **p, struct dentry *dentry,
3394a8599bd8SSage Weil 			       int mds, int drop, int unless)
3395a8599bd8SSage Weil {
3396a8599bd8SSage Weil 	struct inode *dir = dentry->d_parent->d_inode;
3397a8599bd8SSage Weil 	struct ceph_mds_request_release *rel = *p;
3398a8599bd8SSage Weil 	struct ceph_dentry_info *di = ceph_dentry(dentry);
3399a8599bd8SSage Weil 	int force = 0;
3400a8599bd8SSage Weil 	int ret;
3401a8599bd8SSage Weil 
3402a8599bd8SSage Weil 	/*
3403a8599bd8SSage Weil 	 * force an record for the directory caps if we have a dentry lease.
3404be655596SSage Weil 	 * this is racy (can't take i_ceph_lock and d_lock together), but it
3405a8599bd8SSage Weil 	 * doesn't have to be perfect; the mds will revoke anything we don't
3406a8599bd8SSage Weil 	 * release.
3407a8599bd8SSage Weil 	 */
3408a8599bd8SSage Weil 	spin_lock(&dentry->d_lock);
3409a8599bd8SSage Weil 	if (di->lease_session && di->lease_session->s_mds == mds)
3410a8599bd8SSage Weil 		force = 1;
3411a8599bd8SSage Weil 	spin_unlock(&dentry->d_lock);
3412a8599bd8SSage Weil 
3413a8599bd8SSage Weil 	ret = ceph_encode_inode_release(p, dir, mds, drop, unless, force);
3414a8599bd8SSage Weil 
3415a8599bd8SSage Weil 	spin_lock(&dentry->d_lock);
3416a8599bd8SSage Weil 	if (ret && di->lease_session && di->lease_session->s_mds == mds) {
3417a8599bd8SSage Weil 		dout("encode_dentry_release %p mds%d seq %d\n",
3418a8599bd8SSage Weil 		     dentry, mds, (int)di->lease_seq);
3419a8599bd8SSage Weil 		rel->dname_len = cpu_to_le32(dentry->d_name.len);
3420a8599bd8SSage Weil 		memcpy(*p, dentry->d_name.name, dentry->d_name.len);
3421a8599bd8SSage Weil 		*p += dentry->d_name.len;
3422a8599bd8SSage Weil 		rel->dname_seq = cpu_to_le32(di->lease_seq);
34231dadcce3SSage Weil 		__ceph_mdsc_drop_dentry_lease(dentry);
3424a8599bd8SSage Weil 	}
3425a8599bd8SSage Weil 	spin_unlock(&dentry->d_lock);
3426a8599bd8SSage Weil 	return ret;
3427a8599bd8SSage Weil }
3428