xref: /openbmc/linux/include/linux/ceph/libceph.h (revision ce932d0c5589e9766e089c22c66890dfc48fbd94)
1 #ifndef _FS_CEPH_LIBCEPH_H
2 #define _FS_CEPH_LIBCEPH_H
3 
4 #include "ceph_debug.h"
5 
6 #include <asm/unaligned.h>
7 #include <linux/backing-dev.h>
8 #include <linux/completion.h>
9 #include <linux/exportfs.h>
10 #include <linux/bug.h>
11 #include <linux/fs.h>
12 #include <linux/mempool.h>
13 #include <linux/pagemap.h>
14 #include <linux/wait.h>
15 #include <linux/writeback.h>
16 #include <linux/slab.h>
17 
18 #include "types.h"
19 #include "messenger.h"
20 #include "msgpool.h"
21 #include "mon_client.h"
22 #include "osd_client.h"
23 #include "ceph_fs.h"
24 
25 /*
26  * Supported features
27  */
28 #define CEPH_FEATURE_SUPPORTED_DEFAULT CEPH_FEATURE_NOSRCADDR
29 #define CEPH_FEATURE_REQUIRED_DEFAULT  CEPH_FEATURE_NOSRCADDR
30 
31 /*
32  * mount options
33  */
34 #define CEPH_OPT_FSID             (1<<0)
35 #define CEPH_OPT_NOSHARE          (1<<1) /* don't share client with other sbs */
36 #define CEPH_OPT_MYIP             (1<<2) /* specified my ip */
37 #define CEPH_OPT_NOCRC            (1<<3) /* no data crc on writes */
38 
39 #define CEPH_OPT_DEFAULT   (0)
40 
41 #define ceph_set_opt(client, opt) \
42 	(client)->options->flags |= CEPH_OPT_##opt;
43 #define ceph_test_opt(client, opt) \
44 	(!!((client)->options->flags & CEPH_OPT_##opt))
45 
46 struct ceph_options {
47 	int flags;
48 	struct ceph_fsid fsid;
49 	struct ceph_entity_addr my_addr;
50 	int mount_timeout;
51 	int osd_idle_ttl;
52 	int osd_timeout;
53 	int osd_keepalive_timeout;
54 
55 	/*
56 	 * any type that can't be simply compared or doesn't need need
57 	 * to be compared should go beyond this point,
58 	 * ceph_compare_options() should be updated accordingly
59 	 */
60 
61 	struct ceph_entity_addr *mon_addr; /* should be the first
62 					      pointer type of args */
63 	int num_mon;
64 	char *name;
65 	struct ceph_crypto_key *key;
66 };
67 
68 /*
69  * defaults
70  */
71 #define CEPH_MOUNT_TIMEOUT_DEFAULT  60
72 #define CEPH_OSD_TIMEOUT_DEFAULT    60  /* seconds */
73 #define CEPH_OSD_KEEPALIVE_DEFAULT  5
74 #define CEPH_OSD_IDLE_TTL_DEFAULT    60
75 
76 #define CEPH_MSG_MAX_FRONT_LEN	(16*1024*1024)
77 #define CEPH_MSG_MAX_DATA_LEN	(16*1024*1024)
78 
79 #define CEPH_AUTH_NAME_DEFAULT   "guest"
80 
81 /*
82  * Delay telling the MDS we no longer want caps, in case we reopen
83  * the file.  Delay a minimum amount of time, even if we send a cap
84  * message for some other reason.  Otherwise, take the oppotunity to
85  * update the mds to avoid sending another message later.
86  */
87 #define CEPH_CAPS_WANTED_DELAY_MIN_DEFAULT      5  /* cap release delay */
88 #define CEPH_CAPS_WANTED_DELAY_MAX_DEFAULT     60  /* cap release delay */
89 
90 #define CEPH_CAP_RELEASE_SAFETY_DEFAULT        (CEPH_CAPS_PER_RELEASE * 4)
91 
92 /* mount state */
93 enum {
94 	CEPH_MOUNT_MOUNTING,
95 	CEPH_MOUNT_MOUNTED,
96 	CEPH_MOUNT_UNMOUNTING,
97 	CEPH_MOUNT_UNMOUNTED,
98 	CEPH_MOUNT_SHUTDOWN,
99 };
100 
101 /*
102  * subtract jiffies
103  */
104 static inline unsigned long time_sub(unsigned long a, unsigned long b)
105 {
106 	BUG_ON(time_after(b, a));
107 	return (long)a - (long)b;
108 }
109 
110 struct ceph_mds_client;
111 
112 /*
113  * per client state
114  *
115  * possibly shared by multiple mount points, if they are
116  * mounting the same ceph filesystem/cluster.
117  */
118 struct ceph_client {
119 	struct ceph_fsid fsid;
120 	bool have_fsid;
121 
122 	void *private;
123 
124 	struct ceph_options *options;
125 
126 	struct mutex mount_mutex;      /* serialize mount attempts */
127 	wait_queue_head_t auth_wq;
128 	int auth_err;
129 
130 	int (*extra_mon_dispatch)(struct ceph_client *, struct ceph_msg *);
131 
132 	u32 supported_features;
133 	u32 required_features;
134 
135 	struct ceph_messenger *msgr;   /* messenger instance */
136 	struct ceph_mon_client monc;
137 	struct ceph_osd_client osdc;
138 
139 #ifdef CONFIG_DEBUG_FS
140 	struct dentry *debugfs_dir;
141 	struct dentry *debugfs_monmap;
142 	struct dentry *debugfs_osdmap;
143 #endif
144 };
145 
146 
147 
148 /*
149  * snapshots
150  */
151 
152 /*
153  * A "snap context" is the set of existing snapshots when we
154  * write data.  It is used by the OSD to guide its COW behavior.
155  *
156  * The ceph_snap_context is refcounted, and attached to each dirty
157  * page, indicating which context the dirty data belonged when it was
158  * dirtied.
159  */
160 struct ceph_snap_context {
161 	atomic_t nref;
162 	u64 seq;
163 	int num_snaps;
164 	u64 snaps[];
165 };
166 
167 static inline struct ceph_snap_context *
168 ceph_get_snap_context(struct ceph_snap_context *sc)
169 {
170 	/*
171 	printk("get_snap_context %p %d -> %d\n", sc, atomic_read(&sc->nref),
172 	       atomic_read(&sc->nref)+1);
173 	*/
174 	if (sc)
175 		atomic_inc(&sc->nref);
176 	return sc;
177 }
178 
179 static inline void ceph_put_snap_context(struct ceph_snap_context *sc)
180 {
181 	if (!sc)
182 		return;
183 	/*
184 	printk("put_snap_context %p %d -> %d\n", sc, atomic_read(&sc->nref),
185 	       atomic_read(&sc->nref)-1);
186 	*/
187 	if (atomic_dec_and_test(&sc->nref)) {
188 		/*printk(" deleting snap_context %p\n", sc);*/
189 		kfree(sc);
190 	}
191 }
192 
193 /*
194  * calculate the number of pages a given length and offset map onto,
195  * if we align the data.
196  */
197 static inline int calc_pages_for(u64 off, u64 len)
198 {
199 	return ((off+len+PAGE_CACHE_SIZE-1) >> PAGE_CACHE_SHIFT) -
200 		(off >> PAGE_CACHE_SHIFT);
201 }
202 
203 /* ceph_common.c */
204 extern const char *ceph_msg_type_name(int type);
205 extern int ceph_check_fsid(struct ceph_client *client, struct ceph_fsid *fsid);
206 extern struct kmem_cache *ceph_inode_cachep;
207 extern struct kmem_cache *ceph_cap_cachep;
208 extern struct kmem_cache *ceph_dentry_cachep;
209 extern struct kmem_cache *ceph_file_cachep;
210 
211 extern struct ceph_options *ceph_parse_options(char *options,
212 			      const char *dev_name, const char *dev_name_end,
213 			      int (*parse_extra_token)(char *c, void *private),
214 			      void *private);
215 extern void ceph_destroy_options(struct ceph_options *opt);
216 extern int ceph_compare_options(struct ceph_options *new_opt,
217 				struct ceph_client *client);
218 extern struct ceph_client *ceph_create_client(struct ceph_options *opt,
219 					      void *private,
220 					      unsigned supported_features,
221 					      unsigned required_features);
222 extern u64 ceph_client_id(struct ceph_client *client);
223 extern void ceph_destroy_client(struct ceph_client *client);
224 extern int __ceph_open_session(struct ceph_client *client,
225 			       unsigned long started);
226 extern int ceph_open_session(struct ceph_client *client);
227 
228 /* pagevec.c */
229 extern void ceph_release_page_vector(struct page **pages, int num_pages);
230 
231 extern struct page **ceph_get_direct_page_vector(const char __user *data,
232 						 int num_pages,
233 						 bool write_page);
234 extern void ceph_put_page_vector(struct page **pages, int num_pages,
235 				 bool dirty);
236 extern void ceph_release_page_vector(struct page **pages, int num_pages);
237 extern struct page **ceph_alloc_page_vector(int num_pages, gfp_t flags);
238 extern int ceph_copy_user_to_page_vector(struct page **pages,
239 					 const char __user *data,
240 					 loff_t off, size_t len);
241 extern int ceph_copy_to_page_vector(struct page **pages,
242 				    const char *data,
243 				    loff_t off, size_t len);
244 extern int ceph_copy_from_page_vector(struct page **pages,
245 				    char *data,
246 				    loff_t off, size_t len);
247 extern int ceph_copy_page_vector_to_user(struct page **pages, char __user *data,
248 				    loff_t off, size_t len);
249 extern void ceph_zero_page_vector_range(int off, int len, struct page **pages);
250 
251 
252 #endif /* _FS_CEPH_SUPER_H */
253