Linux Kernel  3.7.1
 All Data Structures Namespaces Files Functions Variables Typedefs Enumerations Enumerator Macros Groups Pages
libceph.h
Go to the documentation of this file.
1 #ifndef _FS_CEPH_LIBCEPH_H
2 #define _FS_CEPH_LIBCEPH_H
3 
4 #include <linux/ceph/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 <linux/ceph/types.h>
19 #include <linux/ceph/messenger.h>
20 #include <linux/ceph/msgpool.h>
21 #include <linux/ceph/mon_client.h>
22 #include <linux/ceph/osd_client.h>
23 #include <linux/ceph/ceph_fs.h>
24 
25 /*
26  * mount options
27  */
28 #define CEPH_OPT_FSID (1<<0)
29 #define CEPH_OPT_NOSHARE (1<<1) /* don't share client with other sbs */
30 #define CEPH_OPT_MYIP (1<<2) /* specified my ip */
31 #define CEPH_OPT_NOCRC (1<<3) /* no data crc on writes */
32 
33 #define CEPH_OPT_DEFAULT (0)
34 
35 #define ceph_set_opt(client, opt) \
36  (client)->options->flags |= CEPH_OPT_##opt;
37 #define ceph_test_opt(client, opt) \
38  (!!((client)->options->flags & CEPH_OPT_##opt))
39 
40 struct ceph_options {
41  int flags;
42  struct ceph_fsid fsid;
43  struct ceph_entity_addr my_addr;
44  int mount_timeout;
45  int osd_idle_ttl;
46  int osd_timeout;
47  int osd_keepalive_timeout;
48 
49  /*
50  * any type that can't be simply compared or doesn't need need
51  * to be compared should go beyond this point,
52  * ceph_compare_options() should be updated accordingly
53  */
54 
55  struct ceph_entity_addr *mon_addr; /* should be the first
56  pointer type of args */
57  int num_mon;
58  char *name;
59  struct ceph_crypto_key *key;
60 };
61 
62 /*
63  * defaults
64  */
65 #define CEPH_MOUNT_TIMEOUT_DEFAULT 60
66 #define CEPH_OSD_TIMEOUT_DEFAULT 60 /* seconds */
67 #define CEPH_OSD_KEEPALIVE_DEFAULT 5
68 #define CEPH_OSD_IDLE_TTL_DEFAULT 60
69 
70 #define CEPH_MSG_MAX_FRONT_LEN (16*1024*1024)
71 #define CEPH_MSG_MAX_DATA_LEN (16*1024*1024)
72 
73 #define CEPH_AUTH_NAME_DEFAULT "guest"
74 
75 /*
76  * Delay telling the MDS we no longer want caps, in case we reopen
77  * the file. Delay a minimum amount of time, even if we send a cap
78  * message for some other reason. Otherwise, take the oppotunity to
79  * update the mds to avoid sending another message later.
80  */
81 #define CEPH_CAPS_WANTED_DELAY_MIN_DEFAULT 5 /* cap release delay */
82 #define CEPH_CAPS_WANTED_DELAY_MAX_DEFAULT 60 /* cap release delay */
83 
84 #define CEPH_CAP_RELEASE_SAFETY_DEFAULT (CEPH_CAPS_PER_RELEASE * 4)
85 
86 /* mount state */
87 enum {
88  CEPH_MOUNT_MOUNTING,
89  CEPH_MOUNT_MOUNTED,
90  CEPH_MOUNT_UNMOUNTING,
91  CEPH_MOUNT_UNMOUNTED,
92  CEPH_MOUNT_SHUTDOWN,
93 };
94 
95 /*
96  * subtract jiffies
97  */
98 static inline unsigned long time_sub(unsigned long a, unsigned long b)
99 {
100  BUG_ON(time_after(b, a));
101  return (long)a - (long)b;
102 }
103 
104 struct ceph_mds_client;
105 
106 /*
107  * per client state
108  *
109  * possibly shared by multiple mount points, if they are
110  * mounting the same ceph filesystem/cluster.
111  */
112 struct ceph_client {
113  struct ceph_fsid fsid;
114  bool have_fsid;
115 
116  void *private;
117 
118  struct ceph_options *options;
119 
120  struct mutex mount_mutex; /* serialize mount attempts */
121  wait_queue_head_t auth_wq;
122  int auth_err;
123 
124  int (*extra_mon_dispatch)(struct ceph_client *, struct ceph_msg *);
125 
126  u32 supported_features;
127  u32 required_features;
128 
129  struct ceph_messenger msgr; /* messenger instance */
130  struct ceph_mon_client monc;
131  struct ceph_osd_client osdc;
132 
133 #ifdef CONFIG_DEBUG_FS
134  struct dentry *debugfs_dir;
135  struct dentry *debugfs_monmap;
136  struct dentry *debugfs_osdmap;
137 #endif
138 };
139 
140 
141 
142 /*
143  * snapshots
144  */
145 
146 /*
147  * A "snap context" is the set of existing snapshots when we
148  * write data. It is used by the OSD to guide its COW behavior.
149  *
150  * The ceph_snap_context is refcounted, and attached to each dirty
151  * page, indicating which context the dirty data belonged when it was
152  * dirtied.
153  */
154 struct ceph_snap_context {
155  atomic_t nref;
156  u64 seq;
157  u32 num_snaps;
158  u64 snaps[];
159 };
160 
161 static inline struct ceph_snap_context *
162 ceph_get_snap_context(struct ceph_snap_context *sc)
163 {
164  /*
165  printk("get_snap_context %p %d -> %d\n", sc, atomic_read(&sc->nref),
166  atomic_read(&sc->nref)+1);
167  */
168  if (sc)
169  atomic_inc(&sc->nref);
170  return sc;
171 }
172 
173 static inline void ceph_put_snap_context(struct ceph_snap_context *sc)
174 {
175  if (!sc)
176  return;
177  /*
178  printk("put_snap_context %p %d -> %d\n", sc, atomic_read(&sc->nref),
179  atomic_read(&sc->nref)-1);
180  */
181  if (atomic_dec_and_test(&sc->nref)) {
182  /*printk(" deleting snap_context %p\n", sc);*/
183  kfree(sc);
184  }
185 }
186 
187 /*
188  * calculate the number of pages a given length and offset map onto,
189  * if we align the data.
190  */
191 static inline int calc_pages_for(u64 off, u64 len)
192 {
193  return ((off+len+PAGE_CACHE_SIZE-1) >> PAGE_CACHE_SHIFT) -
194  (off >> PAGE_CACHE_SHIFT);
195 }
196 
197 /* ceph_common.c */
198 extern const char *ceph_msg_type_name(int type);
199 extern int ceph_check_fsid(struct ceph_client *client, struct ceph_fsid *fsid);
200 extern struct kmem_cache *ceph_inode_cachep;
201 extern struct kmem_cache *ceph_cap_cachep;
202 extern struct kmem_cache *ceph_dentry_cachep;
203 extern struct kmem_cache *ceph_file_cachep;
204 
205 extern struct ceph_options *ceph_parse_options(char *options,
206  const char *dev_name, const char *dev_name_end,
207  int (*parse_extra_token)(char *c, void *private),
208  void *private);
209 extern void ceph_destroy_options(struct ceph_options *opt);
210 extern int ceph_compare_options(struct ceph_options *new_opt,
211  struct ceph_client *client);
212 extern struct ceph_client *ceph_create_client(struct ceph_options *opt,
213  void *private,
214  unsigned supported_features,
215  unsigned required_features);
216 extern u64 ceph_client_id(struct ceph_client *client);
217 extern void ceph_destroy_client(struct ceph_client *client);
218 extern int __ceph_open_session(struct ceph_client *client,
219  unsigned long started);
220 extern int ceph_open_session(struct ceph_client *client);
221 
222 /* pagevec.c */
223 extern void ceph_release_page_vector(struct page **pages, int num_pages);
224 
225 extern struct page **ceph_get_direct_page_vector(const char __user *data,
226  int num_pages,
227  bool write_page);
228 extern void ceph_put_page_vector(struct page **pages, int num_pages,
229  bool dirty);
230 extern void ceph_release_page_vector(struct page **pages, int num_pages);
231 extern struct page **ceph_alloc_page_vector(int num_pages, gfp_t flags);
232 extern int ceph_copy_user_to_page_vector(struct page **pages,
233  const char __user *data,
234  loff_t off, size_t len);
235 extern int ceph_copy_to_page_vector(struct page **pages,
236  const char *data,
237  loff_t off, size_t len);
238 extern int ceph_copy_from_page_vector(struct page **pages,
239  char *data,
240  loff_t off, size_t len);
241 extern int ceph_copy_page_vector_to_user(struct page **pages, char __user *data,
242  loff_t off, size_t len);
243 extern void ceph_zero_page_vector_range(int off, int len, struct page **pages);
244 
245 
246 #endif /* _FS_CEPH_SUPER_H */
Generated on Thu Jan 10 2013 14:51:10 for Linux Kernel by   doxygen 1.8.2