xref: /openbmc/linux/fs/nfsd/blocklayout.c (revision 8dce88fe)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2014-2016 Christoph Hellwig.
4  */
5 #include <linux/exportfs.h>
6 #include <linux/iomap.h>
7 #include <linux/genhd.h>
8 #include <linux/slab.h>
9 #include <linux/pr.h>
10 
11 #include <linux/nfsd/debug.h>
12 
13 #include "blocklayoutxdr.h"
14 #include "pnfs.h"
15 #include "filecache.h"
16 
17 #define NFSDDBG_FACILITY	NFSDDBG_PNFS
18 
19 
20 static __be32
21 nfsd4_block_proc_layoutget(struct inode *inode, const struct svc_fh *fhp,
22 		struct nfsd4_layoutget *args)
23 {
24 	struct nfsd4_layout_seg *seg = &args->lg_seg;
25 	struct super_block *sb = inode->i_sb;
26 	u32 block_size = i_blocksize(inode);
27 	struct pnfs_block_extent *bex;
28 	struct iomap iomap;
29 	u32 device_generation = 0;
30 	int error;
31 
32 	if (seg->offset & (block_size - 1)) {
33 		dprintk("pnfsd: I/O misaligned\n");
34 		goto out_layoutunavailable;
35 	}
36 
37 	/*
38 	 * Some clients barf on non-zero block numbers for NONE or INVALID
39 	 * layouts, so make sure to zero the whole structure.
40 	 */
41 	error = -ENOMEM;
42 	bex = kzalloc(sizeof(*bex), GFP_KERNEL);
43 	if (!bex)
44 		goto out_error;
45 	args->lg_content = bex;
46 
47 	error = sb->s_export_op->map_blocks(inode, seg->offset, seg->length,
48 					    &iomap, seg->iomode != IOMODE_READ,
49 					    &device_generation);
50 	if (error) {
51 		if (error == -ENXIO)
52 			goto out_layoutunavailable;
53 		goto out_error;
54 	}
55 
56 	if (iomap.length < args->lg_minlength) {
57 		dprintk("pnfsd: extent smaller than minlength\n");
58 		goto out_layoutunavailable;
59 	}
60 
61 	switch (iomap.type) {
62 	case IOMAP_MAPPED:
63 		if (seg->iomode == IOMODE_READ)
64 			bex->es = PNFS_BLOCK_READ_DATA;
65 		else
66 			bex->es = PNFS_BLOCK_READWRITE_DATA;
67 		bex->soff = iomap.addr;
68 		break;
69 	case IOMAP_UNWRITTEN:
70 		if (seg->iomode & IOMODE_RW) {
71 			/*
72 			 * Crack monkey special case from section 2.3.1.
73 			 */
74 			if (args->lg_minlength == 0) {
75 				dprintk("pnfsd: no soup for you!\n");
76 				goto out_layoutunavailable;
77 			}
78 
79 			bex->es = PNFS_BLOCK_INVALID_DATA;
80 			bex->soff = iomap.addr;
81 			break;
82 		}
83 		fallthrough;
84 	case IOMAP_HOLE:
85 		if (seg->iomode == IOMODE_READ) {
86 			bex->es = PNFS_BLOCK_NONE_DATA;
87 			break;
88 		}
89 		fallthrough;
90 	case IOMAP_DELALLOC:
91 	default:
92 		WARN(1, "pnfsd: filesystem returned %d extent\n", iomap.type);
93 		goto out_layoutunavailable;
94 	}
95 
96 	error = nfsd4_set_deviceid(&bex->vol_id, fhp, device_generation);
97 	if (error)
98 		goto out_error;
99 	bex->foff = iomap.offset;
100 	bex->len = iomap.length;
101 
102 	seg->offset = iomap.offset;
103 	seg->length = iomap.length;
104 
105 	dprintk("GET: 0x%llx:0x%llx %d\n", bex->foff, bex->len, bex->es);
106 	return 0;
107 
108 out_error:
109 	seg->length = 0;
110 	return nfserrno(error);
111 out_layoutunavailable:
112 	seg->length = 0;
113 	return nfserr_layoutunavailable;
114 }
115 
116 static __be32
117 nfsd4_block_commit_blocks(struct inode *inode, struct nfsd4_layoutcommit *lcp,
118 		struct iomap *iomaps, int nr_iomaps)
119 {
120 	loff_t new_size = lcp->lc_last_wr + 1;
121 	struct iattr iattr = { .ia_valid = 0 };
122 	int error;
123 
124 	if (lcp->lc_mtime.tv_nsec == UTIME_NOW ||
125 	    timespec64_compare(&lcp->lc_mtime, &inode->i_mtime) < 0)
126 		lcp->lc_mtime = current_time(inode);
127 	iattr.ia_valid |= ATTR_ATIME | ATTR_CTIME | ATTR_MTIME;
128 	iattr.ia_atime = iattr.ia_ctime = iattr.ia_mtime = lcp->lc_mtime;
129 
130 	if (new_size > i_size_read(inode)) {
131 		iattr.ia_valid |= ATTR_SIZE;
132 		iattr.ia_size = new_size;
133 	}
134 
135 	error = inode->i_sb->s_export_op->commit_blocks(inode, iomaps,
136 			nr_iomaps, &iattr);
137 	kfree(iomaps);
138 	return nfserrno(error);
139 }
140 
141 #ifdef CONFIG_NFSD_BLOCKLAYOUT
142 static int
143 nfsd4_block_get_device_info_simple(struct super_block *sb,
144 		struct nfsd4_getdeviceinfo *gdp)
145 {
146 	struct pnfs_block_deviceaddr *dev;
147 	struct pnfs_block_volume *b;
148 
149 	dev = kzalloc(sizeof(struct pnfs_block_deviceaddr) +
150 		      sizeof(struct pnfs_block_volume), GFP_KERNEL);
151 	if (!dev)
152 		return -ENOMEM;
153 	gdp->gd_device = dev;
154 
155 	dev->nr_volumes = 1;
156 	b = &dev->volumes[0];
157 
158 	b->type = PNFS_BLOCK_VOLUME_SIMPLE;
159 	b->simple.sig_len = PNFS_BLOCK_UUID_LEN;
160 	return sb->s_export_op->get_uuid(sb, b->simple.sig, &b->simple.sig_len,
161 			&b->simple.offset);
162 }
163 
164 static __be32
165 nfsd4_block_proc_getdeviceinfo(struct super_block *sb,
166 		struct svc_rqst *rqstp,
167 		struct nfs4_client *clp,
168 		struct nfsd4_getdeviceinfo *gdp)
169 {
170 	if (bdev_is_partition(sb->s_bdev))
171 		return nfserr_inval;
172 	return nfserrno(nfsd4_block_get_device_info_simple(sb, gdp));
173 }
174 
175 static __be32
176 nfsd4_block_proc_layoutcommit(struct inode *inode,
177 		struct nfsd4_layoutcommit *lcp)
178 {
179 	struct iomap *iomaps;
180 	int nr_iomaps;
181 
182 	nr_iomaps = nfsd4_block_decode_layoutupdate(lcp->lc_up_layout,
183 			lcp->lc_up_len, &iomaps, i_blocksize(inode));
184 	if (nr_iomaps < 0)
185 		return nfserrno(nr_iomaps);
186 
187 	return nfsd4_block_commit_blocks(inode, lcp, iomaps, nr_iomaps);
188 }
189 
190 const struct nfsd4_layout_ops bl_layout_ops = {
191 	/*
192 	 * Pretend that we send notification to the client.  This is a blatant
193 	 * lie to force recent Linux clients to cache our device IDs.
194 	 * We rarely ever change the device ID, so the harm of leaking deviceids
195 	 * for a while isn't too bad.  Unfortunately RFC5661 is a complete mess
196 	 * in this regard, but I filed errata 4119 for this a while ago, and
197 	 * hopefully the Linux client will eventually start caching deviceids
198 	 * without this again.
199 	 */
200 	.notify_types		=
201 			NOTIFY_DEVICEID4_DELETE | NOTIFY_DEVICEID4_CHANGE,
202 	.proc_getdeviceinfo	= nfsd4_block_proc_getdeviceinfo,
203 	.encode_getdeviceinfo	= nfsd4_block_encode_getdeviceinfo,
204 	.proc_layoutget		= nfsd4_block_proc_layoutget,
205 	.encode_layoutget	= nfsd4_block_encode_layoutget,
206 	.proc_layoutcommit	= nfsd4_block_proc_layoutcommit,
207 };
208 #endif /* CONFIG_NFSD_BLOCKLAYOUT */
209 
210 #ifdef CONFIG_NFSD_SCSILAYOUT
211 #define NFSD_MDS_PR_KEY		0x0100000000000000ULL
212 
213 /*
214  * We use the client ID as a unique key for the reservations.
215  * This allows us to easily fence a client when recalls fail.
216  */
217 static u64 nfsd4_scsi_pr_key(struct nfs4_client *clp)
218 {
219 	return ((u64)clp->cl_clientid.cl_boot << 32) | clp->cl_clientid.cl_id;
220 }
221 
222 static const u8 designator_types[] = {
223 	PS_DESIGNATOR_EUI64,
224 	PS_DESIGNATOR_NAA,
225 };
226 
227 static int
228 nfsd4_block_get_unique_id(struct gendisk *disk, struct pnfs_block_volume *b)
229 {
230 	int ret, i;
231 
232 	for (i = 0; i < ARRAY_SIZE(designator_types); i++) {
233 		u8 type = designator_types[i];
234 
235 		ret = disk->fops->get_unique_id(disk, b->scsi.designator, type);
236 		if (ret > 0) {
237 			b->scsi.code_set = PS_CODE_SET_BINARY;
238 			b->scsi.designator_type = type;
239 			b->scsi.designator_len = ret;
240 			return 0;
241 		}
242 	}
243 
244 	return -EINVAL;
245 }
246 
247 static int
248 nfsd4_block_get_device_info_scsi(struct super_block *sb,
249 		struct nfs4_client *clp,
250 		struct nfsd4_getdeviceinfo *gdp)
251 {
252 	struct pnfs_block_deviceaddr *dev;
253 	struct pnfs_block_volume *b;
254 	const struct pr_ops *ops;
255 	int ret;
256 
257 	dev = kzalloc(sizeof(struct pnfs_block_deviceaddr) +
258 		      sizeof(struct pnfs_block_volume), GFP_KERNEL);
259 	if (!dev)
260 		return -ENOMEM;
261 	gdp->gd_device = dev;
262 
263 	dev->nr_volumes = 1;
264 	b = &dev->volumes[0];
265 
266 	b->type = PNFS_BLOCK_VOLUME_SCSI;
267 	b->scsi.pr_key = nfsd4_scsi_pr_key(clp);
268 
269 	ret = nfsd4_block_get_unique_id(sb->s_bdev->bd_disk, b);
270 	if (ret < 0)
271 		goto out_free_dev;
272 
273 	ret = -EINVAL;
274 	ops = sb->s_bdev->bd_disk->fops->pr_ops;
275 	if (!ops) {
276 		pr_err("pNFS: device %s does not support PRs.\n",
277 			sb->s_id);
278 		goto out_free_dev;
279 	}
280 
281 	ret = ops->pr_register(sb->s_bdev, 0, NFSD_MDS_PR_KEY, true);
282 	if (ret) {
283 		pr_err("pNFS: failed to register key for device %s.\n",
284 			sb->s_id);
285 		goto out_free_dev;
286 	}
287 
288 	ret = ops->pr_reserve(sb->s_bdev, NFSD_MDS_PR_KEY,
289 			PR_EXCLUSIVE_ACCESS_REG_ONLY, 0);
290 	if (ret) {
291 		pr_err("pNFS: failed to reserve device %s.\n",
292 			sb->s_id);
293 		goto out_free_dev;
294 	}
295 
296 	return 0;
297 
298 out_free_dev:
299 	kfree(dev);
300 	return ret;
301 }
302 
303 static __be32
304 nfsd4_scsi_proc_getdeviceinfo(struct super_block *sb,
305 		struct svc_rqst *rqstp,
306 		struct nfs4_client *clp,
307 		struct nfsd4_getdeviceinfo *gdp)
308 {
309 	if (bdev_is_partition(sb->s_bdev))
310 		return nfserr_inval;
311 	return nfserrno(nfsd4_block_get_device_info_scsi(sb, clp, gdp));
312 }
313 static __be32
314 nfsd4_scsi_proc_layoutcommit(struct inode *inode,
315 		struct nfsd4_layoutcommit *lcp)
316 {
317 	struct iomap *iomaps;
318 	int nr_iomaps;
319 
320 	nr_iomaps = nfsd4_scsi_decode_layoutupdate(lcp->lc_up_layout,
321 			lcp->lc_up_len, &iomaps, i_blocksize(inode));
322 	if (nr_iomaps < 0)
323 		return nfserrno(nr_iomaps);
324 
325 	return nfsd4_block_commit_blocks(inode, lcp, iomaps, nr_iomaps);
326 }
327 
328 static void
329 nfsd4_scsi_fence_client(struct nfs4_layout_stateid *ls)
330 {
331 	struct nfs4_client *clp = ls->ls_stid.sc_client;
332 	struct block_device *bdev = ls->ls_file->nf_file->f_path.mnt->mnt_sb->s_bdev;
333 
334 	bdev->bd_disk->fops->pr_ops->pr_preempt(bdev, NFSD_MDS_PR_KEY,
335 			nfsd4_scsi_pr_key(clp), 0, true);
336 }
337 
338 const struct nfsd4_layout_ops scsi_layout_ops = {
339 	/*
340 	 * Pretend that we send notification to the client.  This is a blatant
341 	 * lie to force recent Linux clients to cache our device IDs.
342 	 * We rarely ever change the device ID, so the harm of leaking deviceids
343 	 * for a while isn't too bad.  Unfortunately RFC5661 is a complete mess
344 	 * in this regard, but I filed errata 4119 for this a while ago, and
345 	 * hopefully the Linux client will eventually start caching deviceids
346 	 * without this again.
347 	 */
348 	.notify_types		=
349 			NOTIFY_DEVICEID4_DELETE | NOTIFY_DEVICEID4_CHANGE,
350 	.proc_getdeviceinfo	= nfsd4_scsi_proc_getdeviceinfo,
351 	.encode_getdeviceinfo	= nfsd4_block_encode_getdeviceinfo,
352 	.proc_layoutget		= nfsd4_block_proc_layoutget,
353 	.encode_layoutget	= nfsd4_block_encode_layoutget,
354 	.proc_layoutcommit	= nfsd4_scsi_proc_layoutcommit,
355 	.fence_client		= nfsd4_scsi_fence_client,
356 };
357 #endif /* CONFIG_NFSD_SCSILAYOUT */
358