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