xref: /openbmc/linux/fs/ceph/super.h (revision 827634ad)
1 #ifndef _FS_CEPH_SUPER_H
2 #define _FS_CEPH_SUPER_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/fs.h>
11 #include <linux/mempool.h>
12 #include <linux/pagemap.h>
13 #include <linux/wait.h>
14 #include <linux/writeback.h>
15 #include <linux/slab.h>
16 #include <linux/posix_acl.h>
17 
18 #include <linux/ceph/libceph.h>
19 
20 #ifdef CONFIG_CEPH_FSCACHE
21 #include <linux/fscache.h>
22 #endif
23 
24 /* f_type in struct statfs */
25 #define CEPH_SUPER_MAGIC 0x00c36400
26 
27 /* large granularity for statfs utilization stats to facilitate
28  * large volume sizes on 32-bit machines. */
29 #define CEPH_BLOCK_SHIFT   22  /* 4 MB */
30 #define CEPH_BLOCK         (1 << CEPH_BLOCK_SHIFT)
31 
32 #define CEPH_MOUNT_OPT_DIRSTAT         (1<<4) /* `cat dirname` for stats */
33 #define CEPH_MOUNT_OPT_RBYTES          (1<<5) /* dir st_bytes = rbytes */
34 #define CEPH_MOUNT_OPT_NOASYNCREADDIR  (1<<7) /* no dcache readdir */
35 #define CEPH_MOUNT_OPT_INO32           (1<<8) /* 32 bit inos */
36 #define CEPH_MOUNT_OPT_DCACHE          (1<<9) /* use dcache for readdir etc */
37 #define CEPH_MOUNT_OPT_FSCACHE         (1<<10) /* use fscache */
38 
39 #define CEPH_MOUNT_OPT_DEFAULT    (CEPH_MOUNT_OPT_RBYTES | \
40 				   CEPH_MOUNT_OPT_DCACHE)
41 
42 #define ceph_set_mount_opt(fsc, opt) \
43 	(fsc)->mount_options->flags |= CEPH_MOUNT_OPT_##opt;
44 #define ceph_test_mount_opt(fsc, opt) \
45 	(!!((fsc)->mount_options->flags & CEPH_MOUNT_OPT_##opt))
46 
47 #define CEPH_RSIZE_DEFAULT             0           /* max read size */
48 #define CEPH_RASIZE_DEFAULT            (8192*1024) /* readahead */
49 #define CEPH_MAX_READDIR_DEFAULT        1024
50 #define CEPH_MAX_READDIR_BYTES_DEFAULT  (512*1024)
51 #define CEPH_SNAPDIRNAME_DEFAULT        ".snap"
52 
53 struct ceph_mount_options {
54 	int flags;
55 	int sb_flags;
56 
57 	int wsize;            /* max write size */
58 	int rsize;            /* max read size */
59 	int rasize;           /* max readahead */
60 	int congestion_kb;    /* max writeback in flight */
61 	int caps_wanted_delay_min, caps_wanted_delay_max;
62 	int cap_release_safety;
63 	int max_readdir;       /* max readdir result (entires) */
64 	int max_readdir_bytes; /* max readdir result (bytes) */
65 
66 	/*
67 	 * everything above this point can be memcmp'd; everything below
68 	 * is handled in compare_mount_options()
69 	 */
70 
71 	char *snapdir_name;   /* default ".snap" */
72 };
73 
74 struct ceph_fs_client {
75 	struct super_block *sb;
76 
77 	struct ceph_mount_options *mount_options;
78 	struct ceph_client *client;
79 
80 	unsigned long mount_state;
81 	int min_caps;                  /* min caps i added */
82 
83 	struct ceph_mds_client *mdsc;
84 
85 	/* writeback */
86 	mempool_t *wb_pagevec_pool;
87 	struct workqueue_struct *wb_wq;
88 	struct workqueue_struct *pg_inv_wq;
89 	struct workqueue_struct *trunc_wq;
90 	atomic_long_t writeback_count;
91 
92 	struct backing_dev_info backing_dev_info;
93 
94 #ifdef CONFIG_DEBUG_FS
95 	struct dentry *debugfs_dentry_lru, *debugfs_caps;
96 	struct dentry *debugfs_congestion_kb;
97 	struct dentry *debugfs_bdi;
98 	struct dentry *debugfs_mdsc, *debugfs_mdsmap;
99 	struct dentry *debugfs_mds_sessions;
100 #endif
101 
102 #ifdef CONFIG_CEPH_FSCACHE
103 	struct fscache_cookie *fscache;
104 	struct workqueue_struct *revalidate_wq;
105 #endif
106 };
107 
108 
109 /*
110  * File i/o capability.  This tracks shared state with the metadata
111  * server that allows us to cache or writeback attributes or to read
112  * and write data.  For any given inode, we should have one or more
113  * capabilities, one issued by each metadata server, and our
114  * cumulative access is the OR of all issued capabilities.
115  *
116  * Each cap is referenced by the inode's i_caps rbtree and by per-mds
117  * session capability lists.
118  */
119 struct ceph_cap {
120 	struct ceph_inode_info *ci;
121 	struct rb_node ci_node;          /* per-ci cap tree */
122 	struct ceph_mds_session *session;
123 	struct list_head session_caps;   /* per-session caplist */
124 	int mds;
125 	u64 cap_id;       /* unique cap id (mds provided) */
126 	int issued;       /* latest, from the mds */
127 	int implemented;  /* implemented superset of issued (for revocation) */
128 	int mds_wanted;
129 	u32 seq, issue_seq, mseq;
130 	u32 cap_gen;      /* active/stale cycle */
131 	unsigned long last_used;
132 	struct list_head caps_item;
133 };
134 
135 #define CHECK_CAPS_NODELAY    1  /* do not delay any further */
136 #define CHECK_CAPS_AUTHONLY   2  /* only check auth cap */
137 #define CHECK_CAPS_FLUSH      4  /* flush any dirty caps */
138 
139 /*
140  * Snapped cap state that is pending flush to mds.  When a snapshot occurs,
141  * we first complete any in-process sync writes and writeback any dirty
142  * data before flushing the snapped state (tracked here) back to the MDS.
143  */
144 struct ceph_cap_snap {
145 	atomic_t nref;
146 	struct ceph_inode_info *ci;
147 	struct list_head ci_item, flushing_item;
148 
149 	u64 follows, flush_tid;
150 	int issued, dirty;
151 	struct ceph_snap_context *context;
152 
153 	umode_t mode;
154 	kuid_t uid;
155 	kgid_t gid;
156 
157 	struct ceph_buffer *xattr_blob;
158 	u64 xattr_version;
159 
160 	u64 size;
161 	struct timespec mtime, atime, ctime;
162 	u64 time_warp_seq;
163 	int writing;   /* a sync write is still in progress */
164 	int dirty_pages;     /* dirty pages awaiting writeback */
165 	bool inline_data;
166 };
167 
168 static inline void ceph_put_cap_snap(struct ceph_cap_snap *capsnap)
169 {
170 	if (atomic_dec_and_test(&capsnap->nref)) {
171 		if (capsnap->xattr_blob)
172 			ceph_buffer_put(capsnap->xattr_blob);
173 		kfree(capsnap);
174 	}
175 }
176 
177 /*
178  * The frag tree describes how a directory is fragmented, potentially across
179  * multiple metadata servers.  It is also used to indicate points where
180  * metadata authority is delegated, and whether/where metadata is replicated.
181  *
182  * A _leaf_ frag will be present in the i_fragtree IFF there is
183  * delegation info.  That is, if mds >= 0 || ndist > 0.
184  */
185 #define CEPH_MAX_DIRFRAG_REP 4
186 
187 struct ceph_inode_frag {
188 	struct rb_node node;
189 
190 	/* fragtree state */
191 	u32 frag;
192 	int split_by;         /* i.e. 2^(split_by) children */
193 
194 	/* delegation and replication info */
195 	int mds;              /* -1 if same authority as parent */
196 	int ndist;            /* >0 if replicated */
197 	int dist[CEPH_MAX_DIRFRAG_REP];
198 };
199 
200 /*
201  * We cache inode xattrs as an encoded blob until they are first used,
202  * at which point we parse them into an rbtree.
203  */
204 struct ceph_inode_xattr {
205 	struct rb_node node;
206 
207 	const char *name;
208 	int name_len;
209 	const char *val;
210 	int val_len;
211 	int dirty;
212 
213 	int should_free_name;
214 	int should_free_val;
215 };
216 
217 /*
218  * Ceph dentry state
219  */
220 struct ceph_dentry_info {
221 	struct ceph_mds_session *lease_session;
222 	u32 lease_gen, lease_shared_gen;
223 	u32 lease_seq;
224 	unsigned long lease_renew_after, lease_renew_from;
225 	struct list_head lru;
226 	struct dentry *dentry;
227 	u64 time;
228 	u64 offset;
229 };
230 
231 struct ceph_inode_xattrs_info {
232 	/*
233 	 * (still encoded) xattr blob. we avoid the overhead of parsing
234 	 * this until someone actually calls getxattr, etc.
235 	 *
236 	 * blob->vec.iov_len == 4 implies there are no xattrs; blob ==
237 	 * NULL means we don't know.
238 	*/
239 	struct ceph_buffer *blob, *prealloc_blob;
240 
241 	struct rb_root index;
242 	bool dirty;
243 	int count;
244 	int names_size;
245 	int vals_size;
246 	u64 version, index_version;
247 };
248 
249 /*
250  * Ceph inode.
251  */
252 struct ceph_inode_info {
253 	struct ceph_vino i_vino;   /* ceph ino + snap */
254 
255 	spinlock_t i_ceph_lock;
256 
257 	u64 i_version;
258 	u64 i_inline_version;
259 	u32 i_time_warp_seq;
260 
261 	unsigned i_ceph_flags;
262 	int i_ordered_count;
263 	atomic_t i_release_count;
264 	atomic_t i_complete_count;
265 
266 	struct ceph_dir_layout i_dir_layout;
267 	struct ceph_file_layout i_layout;
268 	char *i_symlink;
269 
270 	/* for dirs */
271 	struct timespec i_rctime;
272 	u64 i_rbytes, i_rfiles, i_rsubdirs;
273 	u64 i_files, i_subdirs;
274 
275 	struct rb_root i_fragtree;
276 	struct mutex i_fragtree_mutex;
277 
278 	struct ceph_inode_xattrs_info i_xattrs;
279 
280 	/* capabilities.  protected _both_ by i_ceph_lock and cap->session's
281 	 * s_mutex. */
282 	struct rb_root i_caps;           /* cap list */
283 	struct ceph_cap *i_auth_cap;     /* authoritative cap, if any */
284 	unsigned i_dirty_caps, i_flushing_caps;     /* mask of dirtied fields */
285 	struct list_head i_dirty_item, i_flushing_item;
286 	u64 i_cap_flush_seq;
287 	/* we need to track cap writeback on a per-cap-bit basis, to allow
288 	 * overlapping, pipelined cap flushes to the mds.  we can probably
289 	 * reduce the tid to 8 bits if we're concerned about inode size. */
290 	u16 i_cap_flush_last_tid, i_cap_flush_tid[CEPH_CAP_BITS];
291 	wait_queue_head_t i_cap_wq;      /* threads waiting on a capability */
292 	unsigned long i_hold_caps_min; /* jiffies */
293 	unsigned long i_hold_caps_max; /* jiffies */
294 	struct list_head i_cap_delay_list;  /* for delayed cap release to mds */
295 	struct ceph_cap_reservation i_cap_migration_resv;
296 	struct list_head i_cap_snaps;   /* snapped state pending flush to mds */
297 	struct ceph_snap_context *i_head_snapc;  /* set if wr_buffer_head > 0 or
298 						    dirty|flushing caps */
299 	unsigned i_snap_caps;           /* cap bits for snapped files */
300 
301 	int i_nr_by_mode[CEPH_FILE_MODE_NUM];  /* open file counts */
302 
303 	struct mutex i_truncate_mutex;
304 	u32 i_truncate_seq;        /* last truncate to smaller size */
305 	u64 i_truncate_size;       /*  and the size we last truncated down to */
306 	int i_truncate_pending;    /*  still need to call vmtruncate */
307 
308 	u64 i_max_size;            /* max file size authorized by mds */
309 	u64 i_reported_size; /* (max_)size reported to or requested of mds */
310 	u64 i_wanted_max_size;     /* offset we'd like to write too */
311 	u64 i_requested_max_size;  /* max_size we've requested */
312 
313 	/* held references to caps */
314 	int i_pin_ref;
315 	int i_rd_ref, i_rdcache_ref, i_wr_ref, i_wb_ref;
316 	int i_wrbuffer_ref, i_wrbuffer_ref_head;
317 	u32 i_shared_gen;       /* increment each time we get FILE_SHARED */
318 	u32 i_rdcache_gen;      /* incremented each time we get FILE_CACHE. */
319 	u32 i_rdcache_revoking; /* RDCACHE gen to async invalidate, if any */
320 
321 	struct list_head i_unsafe_writes; /* uncommitted sync writes */
322 	struct list_head i_unsafe_dirops; /* uncommitted mds dir ops */
323 	spinlock_t i_unsafe_lock;
324 
325 	struct ceph_snap_realm *i_snap_realm; /* snap realm (if caps) */
326 	int i_snap_realm_counter; /* snap realm (if caps) */
327 	struct list_head i_snap_realm_item;
328 	struct list_head i_snap_flush_item;
329 
330 	struct work_struct i_wb_work;  /* writeback work */
331 	struct work_struct i_pg_inv_work;  /* page invalidation work */
332 
333 	struct work_struct i_vmtruncate_work;
334 
335 #ifdef CONFIG_CEPH_FSCACHE
336 	struct fscache_cookie *fscache;
337 	u32 i_fscache_gen; /* sequence, for delayed fscache validate */
338 	struct work_struct i_revalidate_work;
339 #endif
340 	struct inode vfs_inode; /* at end */
341 };
342 
343 static inline struct ceph_inode_info *ceph_inode(struct inode *inode)
344 {
345 	return container_of(inode, struct ceph_inode_info, vfs_inode);
346 }
347 
348 static inline struct ceph_fs_client *ceph_inode_to_client(struct inode *inode)
349 {
350 	return (struct ceph_fs_client *)inode->i_sb->s_fs_info;
351 }
352 
353 static inline struct ceph_fs_client *ceph_sb_to_client(struct super_block *sb)
354 {
355 	return (struct ceph_fs_client *)sb->s_fs_info;
356 }
357 
358 static inline struct ceph_vino ceph_vino(struct inode *inode)
359 {
360 	return ceph_inode(inode)->i_vino;
361 }
362 
363 /*
364  * ino_t is <64 bits on many architectures, blech.
365  *
366  *               i_ino (kernel inode)   st_ino (userspace)
367  * i386          32                     32
368  * x86_64+ino32  64                     32
369  * x86_64        64                     64
370  */
371 static inline u32 ceph_ino_to_ino32(__u64 vino)
372 {
373 	u32 ino = vino & 0xffffffff;
374 	ino ^= vino >> 32;
375 	if (!ino)
376 		ino = 2;
377 	return ino;
378 }
379 
380 /*
381  * kernel i_ino value
382  */
383 static inline ino_t ceph_vino_to_ino(struct ceph_vino vino)
384 {
385 #if BITS_PER_LONG == 32
386 	return ceph_ino_to_ino32(vino.ino);
387 #else
388 	return (ino_t)vino.ino;
389 #endif
390 }
391 
392 /*
393  * user-visible ino (stat, filldir)
394  */
395 #if BITS_PER_LONG == 32
396 static inline ino_t ceph_translate_ino(struct super_block *sb, ino_t ino)
397 {
398 	return ino;
399 }
400 #else
401 static inline ino_t ceph_translate_ino(struct super_block *sb, ino_t ino)
402 {
403 	if (ceph_test_mount_opt(ceph_sb_to_client(sb), INO32))
404 		ino = ceph_ino_to_ino32(ino);
405 	return ino;
406 }
407 #endif
408 
409 
410 /* for printf-style formatting */
411 #define ceph_vinop(i) ceph_inode(i)->i_vino.ino, ceph_inode(i)->i_vino.snap
412 
413 static inline u64 ceph_ino(struct inode *inode)
414 {
415 	return ceph_inode(inode)->i_vino.ino;
416 }
417 static inline u64 ceph_snap(struct inode *inode)
418 {
419 	return ceph_inode(inode)->i_vino.snap;
420 }
421 
422 static inline int ceph_ino_compare(struct inode *inode, void *data)
423 {
424 	struct ceph_vino *pvino = (struct ceph_vino *)data;
425 	struct ceph_inode_info *ci = ceph_inode(inode);
426 	return ci->i_vino.ino == pvino->ino &&
427 		ci->i_vino.snap == pvino->snap;
428 }
429 
430 static inline struct inode *ceph_find_inode(struct super_block *sb,
431 					    struct ceph_vino vino)
432 {
433 	ino_t t = ceph_vino_to_ino(vino);
434 	return ilookup5(sb, t, ceph_ino_compare, &vino);
435 }
436 
437 
438 /*
439  * Ceph inode.
440  */
441 #define CEPH_I_DIR_ORDERED	1  /* dentries in dir are ordered */
442 #define CEPH_I_NODELAY		4  /* do not delay cap release */
443 #define CEPH_I_FLUSH		8  /* do not delay flush of dirty metadata */
444 #define CEPH_I_NOFLUSH		16 /* do not flush dirty caps */
445 
446 static inline void __ceph_dir_set_complete(struct ceph_inode_info *ci,
447 					   int release_count, int ordered_count)
448 {
449 	atomic_set(&ci->i_complete_count, release_count);
450 	if (ci->i_ordered_count == ordered_count)
451 		ci->i_ceph_flags |= CEPH_I_DIR_ORDERED;
452 	else
453 		ci->i_ceph_flags &= ~CEPH_I_DIR_ORDERED;
454 }
455 
456 static inline void __ceph_dir_clear_complete(struct ceph_inode_info *ci)
457 {
458 	atomic_inc(&ci->i_release_count);
459 }
460 
461 static inline bool __ceph_dir_is_complete(struct ceph_inode_info *ci)
462 {
463 	return atomic_read(&ci->i_complete_count) ==
464 		atomic_read(&ci->i_release_count);
465 }
466 
467 static inline bool __ceph_dir_is_complete_ordered(struct ceph_inode_info *ci)
468 {
469 	return __ceph_dir_is_complete(ci) &&
470 		(ci->i_ceph_flags & CEPH_I_DIR_ORDERED);
471 }
472 
473 static inline void ceph_dir_clear_complete(struct inode *inode)
474 {
475 	__ceph_dir_clear_complete(ceph_inode(inode));
476 }
477 
478 static inline void ceph_dir_clear_ordered(struct inode *inode)
479 {
480 	struct ceph_inode_info *ci = ceph_inode(inode);
481 	spin_lock(&ci->i_ceph_lock);
482 	ci->i_ordered_count++;
483 	ci->i_ceph_flags &= ~CEPH_I_DIR_ORDERED;
484 	spin_unlock(&ci->i_ceph_lock);
485 }
486 
487 static inline bool ceph_dir_is_complete_ordered(struct inode *inode)
488 {
489 	struct ceph_inode_info *ci = ceph_inode(inode);
490 	bool ret;
491 	spin_lock(&ci->i_ceph_lock);
492 	ret = __ceph_dir_is_complete_ordered(ci);
493 	spin_unlock(&ci->i_ceph_lock);
494 	return ret;
495 }
496 
497 /* find a specific frag @f */
498 extern struct ceph_inode_frag *__ceph_find_frag(struct ceph_inode_info *ci,
499 						u32 f);
500 
501 /*
502  * choose fragment for value @v.  copy frag content to pfrag, if leaf
503  * exists
504  */
505 extern u32 ceph_choose_frag(struct ceph_inode_info *ci, u32 v,
506 			    struct ceph_inode_frag *pfrag,
507 			    int *found);
508 
509 static inline struct ceph_dentry_info *ceph_dentry(struct dentry *dentry)
510 {
511 	return (struct ceph_dentry_info *)dentry->d_fsdata;
512 }
513 
514 static inline loff_t ceph_make_fpos(unsigned frag, unsigned off)
515 {
516 	return ((loff_t)frag << 32) | (loff_t)off;
517 }
518 
519 /*
520  * caps helpers
521  */
522 static inline bool __ceph_is_any_real_caps(struct ceph_inode_info *ci)
523 {
524 	return !RB_EMPTY_ROOT(&ci->i_caps);
525 }
526 
527 extern int __ceph_caps_issued(struct ceph_inode_info *ci, int *implemented);
528 extern int __ceph_caps_issued_mask(struct ceph_inode_info *ci, int mask, int t);
529 extern int __ceph_caps_issued_other(struct ceph_inode_info *ci,
530 				    struct ceph_cap *cap);
531 
532 static inline int ceph_caps_issued(struct ceph_inode_info *ci)
533 {
534 	int issued;
535 	spin_lock(&ci->i_ceph_lock);
536 	issued = __ceph_caps_issued(ci, NULL);
537 	spin_unlock(&ci->i_ceph_lock);
538 	return issued;
539 }
540 
541 static inline int ceph_caps_issued_mask(struct ceph_inode_info *ci, int mask,
542 					int touch)
543 {
544 	int r;
545 	spin_lock(&ci->i_ceph_lock);
546 	r = __ceph_caps_issued_mask(ci, mask, touch);
547 	spin_unlock(&ci->i_ceph_lock);
548 	return r;
549 }
550 
551 static inline int __ceph_caps_dirty(struct ceph_inode_info *ci)
552 {
553 	return ci->i_dirty_caps | ci->i_flushing_caps;
554 }
555 extern int __ceph_mark_dirty_caps(struct ceph_inode_info *ci, int mask);
556 
557 extern int __ceph_caps_revoking_other(struct ceph_inode_info *ci,
558 				      struct ceph_cap *ocap, int mask);
559 extern int ceph_caps_revoking(struct ceph_inode_info *ci, int mask);
560 extern int __ceph_caps_used(struct ceph_inode_info *ci);
561 
562 extern int __ceph_caps_file_wanted(struct ceph_inode_info *ci);
563 
564 /*
565  * wanted, by virtue of open file modes AND cap refs (buffered/cached data)
566  */
567 static inline int __ceph_caps_wanted(struct ceph_inode_info *ci)
568 {
569 	int w = __ceph_caps_file_wanted(ci) | __ceph_caps_used(ci);
570 	if (w & CEPH_CAP_FILE_BUFFER)
571 		w |= CEPH_CAP_FILE_EXCL;  /* we want EXCL if dirty data */
572 	return w;
573 }
574 
575 /* what the mds thinks we want */
576 extern int __ceph_caps_mds_wanted(struct ceph_inode_info *ci);
577 
578 extern void ceph_caps_init(struct ceph_mds_client *mdsc);
579 extern void ceph_caps_finalize(struct ceph_mds_client *mdsc);
580 extern void ceph_adjust_min_caps(struct ceph_mds_client *mdsc, int delta);
581 extern void ceph_reserve_caps(struct ceph_mds_client *mdsc,
582 			     struct ceph_cap_reservation *ctx, int need);
583 extern int ceph_unreserve_caps(struct ceph_mds_client *mdsc,
584 			       struct ceph_cap_reservation *ctx);
585 extern void ceph_reservation_status(struct ceph_fs_client *client,
586 				    int *total, int *avail, int *used,
587 				    int *reserved, int *min);
588 
589 
590 
591 /*
592  * we keep buffered readdir results attached to file->private_data
593  */
594 #define CEPH_F_SYNC     1
595 #define CEPH_F_ATEND    2
596 
597 struct ceph_file_info {
598 	short fmode;     /* initialized on open */
599 	short flags;     /* CEPH_F_* */
600 
601 	/* readdir: position within the dir */
602 	u32 frag;
603 	struct ceph_mds_request *last_readdir;
604 
605 	/* readdir: position within a frag */
606 	unsigned offset;       /* offset of last chunk, adjusted for . and .. */
607 	unsigned next_offset;  /* offset of next chunk (last_name's + 1) */
608 	char *last_name;       /* last entry in previous chunk */
609 	struct dentry *dentry; /* next dentry (for dcache readdir) */
610 	int dir_release_count;
611 	int dir_ordered_count;
612 
613 	/* used for -o dirstat read() on directory thing */
614 	char *dir_info;
615 	int dir_info_len;
616 };
617 
618 
619 
620 /*
621  * A "snap realm" describes a subset of the file hierarchy sharing
622  * the same set of snapshots that apply to it.  The realms themselves
623  * are organized into a hierarchy, such that children inherit (some of)
624  * the snapshots of their parents.
625  *
626  * All inodes within the realm that have capabilities are linked into a
627  * per-realm list.
628  */
629 struct ceph_snap_realm {
630 	u64 ino;
631 	atomic_t nref;
632 	struct rb_node node;
633 
634 	u64 created, seq;
635 	u64 parent_ino;
636 	u64 parent_since;   /* snapid when our current parent became so */
637 
638 	u64 *prior_parent_snaps;      /* snaps inherited from any parents we */
639 	u32 num_prior_parent_snaps;   /*  had prior to parent_since */
640 	u64 *snaps;                   /* snaps specific to this realm */
641 	u32 num_snaps;
642 
643 	struct ceph_snap_realm *parent;
644 	struct list_head children;       /* list of child realms */
645 	struct list_head child_item;
646 
647 	struct list_head empty_item;     /* if i have ref==0 */
648 
649 	struct list_head dirty_item;     /* if realm needs new context */
650 
651 	/* the current set of snaps for this realm */
652 	struct ceph_snap_context *cached_context;
653 
654 	struct list_head inodes_with_caps;
655 	spinlock_t inodes_with_caps_lock;
656 };
657 
658 static inline int default_congestion_kb(void)
659 {
660 	int congestion_kb;
661 
662 	/*
663 	 * Copied from NFS
664 	 *
665 	 * congestion size, scale with available memory.
666 	 *
667 	 *  64MB:    8192k
668 	 * 128MB:   11585k
669 	 * 256MB:   16384k
670 	 * 512MB:   23170k
671 	 *   1GB:   32768k
672 	 *   2GB:   46340k
673 	 *   4GB:   65536k
674 	 *   8GB:   92681k
675 	 *  16GB:  131072k
676 	 *
677 	 * This allows larger machines to have larger/more transfers.
678 	 * Limit the default to 256M
679 	 */
680 	congestion_kb = (16*int_sqrt(totalram_pages)) << (PAGE_SHIFT-10);
681 	if (congestion_kb > 256*1024)
682 		congestion_kb = 256*1024;
683 
684 	return congestion_kb;
685 }
686 
687 
688 
689 /* snap.c */
690 struct ceph_snap_realm *ceph_lookup_snap_realm(struct ceph_mds_client *mdsc,
691 					       u64 ino);
692 extern void ceph_get_snap_realm(struct ceph_mds_client *mdsc,
693 				struct ceph_snap_realm *realm);
694 extern void ceph_put_snap_realm(struct ceph_mds_client *mdsc,
695 				struct ceph_snap_realm *realm);
696 extern int ceph_update_snap_trace(struct ceph_mds_client *m,
697 				  void *p, void *e, bool deletion,
698 				  struct ceph_snap_realm **realm_ret);
699 extern void ceph_handle_snap(struct ceph_mds_client *mdsc,
700 			     struct ceph_mds_session *session,
701 			     struct ceph_msg *msg);
702 extern void ceph_queue_cap_snap(struct ceph_inode_info *ci);
703 extern int __ceph_finish_cap_snap(struct ceph_inode_info *ci,
704 				  struct ceph_cap_snap *capsnap);
705 extern void ceph_cleanup_empty_realms(struct ceph_mds_client *mdsc);
706 extern int ceph_snap_init(void);
707 extern void ceph_snap_exit(void);
708 
709 /*
710  * a cap_snap is "pending" if it is still awaiting an in-progress
711  * sync write (that may/may not still update size, mtime, etc.).
712  */
713 static inline bool __ceph_have_pending_cap_snap(struct ceph_inode_info *ci)
714 {
715 	return !list_empty(&ci->i_cap_snaps) &&
716 		list_entry(ci->i_cap_snaps.prev, struct ceph_cap_snap,
717 			   ci_item)->writing;
718 }
719 
720 /* inode.c */
721 extern const struct inode_operations ceph_file_iops;
722 
723 extern struct inode *ceph_alloc_inode(struct super_block *sb);
724 extern void ceph_destroy_inode(struct inode *inode);
725 extern int ceph_drop_inode(struct inode *inode);
726 
727 extern struct inode *ceph_get_inode(struct super_block *sb,
728 				    struct ceph_vino vino);
729 extern struct inode *ceph_get_snapdir(struct inode *parent);
730 extern int ceph_fill_file_size(struct inode *inode, int issued,
731 			       u32 truncate_seq, u64 truncate_size, u64 size);
732 extern void ceph_fill_file_time(struct inode *inode, int issued,
733 				u64 time_warp_seq, struct timespec *ctime,
734 				struct timespec *mtime, struct timespec *atime);
735 extern int ceph_fill_trace(struct super_block *sb,
736 			   struct ceph_mds_request *req,
737 			   struct ceph_mds_session *session);
738 extern int ceph_readdir_prepopulate(struct ceph_mds_request *req,
739 				    struct ceph_mds_session *session);
740 
741 extern int ceph_inode_holds_cap(struct inode *inode, int mask);
742 
743 extern int ceph_inode_set_size(struct inode *inode, loff_t size);
744 extern void __ceph_do_pending_vmtruncate(struct inode *inode);
745 extern void ceph_queue_vmtruncate(struct inode *inode);
746 
747 extern void ceph_queue_invalidate(struct inode *inode);
748 extern void ceph_queue_writeback(struct inode *inode);
749 
750 extern int __ceph_do_getattr(struct inode *inode, struct page *locked_page,
751 			     int mask, bool force);
752 static inline int ceph_do_getattr(struct inode *inode, int mask, bool force)
753 {
754 	return __ceph_do_getattr(inode, NULL, mask, force);
755 }
756 extern int ceph_permission(struct inode *inode, int mask);
757 extern int ceph_setattr(struct dentry *dentry, struct iattr *attr);
758 extern int ceph_getattr(struct vfsmount *mnt, struct dentry *dentry,
759 			struct kstat *stat);
760 
761 /* xattr.c */
762 extern int ceph_setxattr(struct dentry *, const char *, const void *,
763 			 size_t, int);
764 int __ceph_setxattr(struct dentry *, const char *, const void *, size_t, int);
765 ssize_t __ceph_getxattr(struct inode *, const char *, void *, size_t);
766 int __ceph_removexattr(struct dentry *, const char *);
767 extern ssize_t ceph_getxattr(struct dentry *, const char *, void *, size_t);
768 extern ssize_t ceph_listxattr(struct dentry *, char *, size_t);
769 extern int ceph_removexattr(struct dentry *, const char *);
770 extern void __ceph_build_xattrs_blob(struct ceph_inode_info *ci);
771 extern void __ceph_destroy_xattrs(struct ceph_inode_info *ci);
772 extern void __init ceph_xattr_init(void);
773 extern void ceph_xattr_exit(void);
774 extern const struct xattr_handler *ceph_xattr_handlers[];
775 
776 /* acl.c */
777 struct ceph_acls_info {
778 	void *default_acl;
779 	void *acl;
780 	struct ceph_pagelist *pagelist;
781 };
782 
783 #ifdef CONFIG_CEPH_FS_POSIX_ACL
784 
785 struct posix_acl *ceph_get_acl(struct inode *, int);
786 int ceph_set_acl(struct inode *inode, struct posix_acl *acl, int type);
787 int ceph_pre_init_acls(struct inode *dir, umode_t *mode,
788 		       struct ceph_acls_info *info);
789 void ceph_init_inode_acls(struct inode *inode, struct ceph_acls_info *info);
790 void ceph_release_acls_info(struct ceph_acls_info *info);
791 
792 static inline void ceph_forget_all_cached_acls(struct inode *inode)
793 {
794        forget_all_cached_acls(inode);
795 }
796 
797 #else
798 
799 #define ceph_get_acl NULL
800 #define ceph_set_acl NULL
801 
802 static inline int ceph_pre_init_acls(struct inode *dir, umode_t *mode,
803 				     struct ceph_acls_info *info)
804 {
805 	return 0;
806 }
807 static inline void ceph_init_inode_acls(struct inode *inode,
808 					struct ceph_acls_info *info)
809 {
810 }
811 static inline void ceph_release_acls_info(struct ceph_acls_info *info)
812 {
813 }
814 static inline int ceph_acl_chmod(struct dentry *dentry, struct inode *inode)
815 {
816 	return 0;
817 }
818 
819 static inline void ceph_forget_all_cached_acls(struct inode *inode)
820 {
821 }
822 
823 #endif
824 
825 /* caps.c */
826 extern const char *ceph_cap_string(int c);
827 extern void ceph_handle_caps(struct ceph_mds_session *session,
828 			     struct ceph_msg *msg);
829 extern struct ceph_cap *ceph_get_cap(struct ceph_mds_client *mdsc,
830 				     struct ceph_cap_reservation *ctx);
831 extern void ceph_add_cap(struct inode *inode,
832 			 struct ceph_mds_session *session, u64 cap_id,
833 			 int fmode, unsigned issued, unsigned wanted,
834 			 unsigned cap, unsigned seq, u64 realmino, int flags,
835 			 struct ceph_cap **new_cap);
836 extern void __ceph_remove_cap(struct ceph_cap *cap, bool queue_release);
837 extern void ceph_put_cap(struct ceph_mds_client *mdsc,
838 			 struct ceph_cap *cap);
839 extern int ceph_is_any_caps(struct inode *inode);
840 
841 extern void __queue_cap_release(struct ceph_mds_session *session, u64 ino,
842 				u64 cap_id, u32 migrate_seq, u32 issue_seq);
843 extern void ceph_queue_caps_release(struct inode *inode);
844 extern int ceph_write_inode(struct inode *inode, struct writeback_control *wbc);
845 extern int ceph_fsync(struct file *file, loff_t start, loff_t end,
846 		      int datasync);
847 extern void ceph_kick_flushing_caps(struct ceph_mds_client *mdsc,
848 				    struct ceph_mds_session *session);
849 extern struct ceph_cap *ceph_get_cap_for_mds(struct ceph_inode_info *ci,
850 					     int mds);
851 extern int ceph_get_cap_mds(struct inode *inode);
852 extern void ceph_get_cap_refs(struct ceph_inode_info *ci, int caps);
853 extern void ceph_put_cap_refs(struct ceph_inode_info *ci, int had);
854 extern void ceph_put_wrbuffer_cap_refs(struct ceph_inode_info *ci, int nr,
855 				       struct ceph_snap_context *snapc);
856 extern void __ceph_flush_snaps(struct ceph_inode_info *ci,
857 			       struct ceph_mds_session **psession,
858 			       int again);
859 extern void ceph_check_caps(struct ceph_inode_info *ci, int flags,
860 			    struct ceph_mds_session *session);
861 extern void ceph_check_delayed_caps(struct ceph_mds_client *mdsc);
862 extern void ceph_flush_dirty_caps(struct ceph_mds_client *mdsc);
863 
864 extern int ceph_encode_inode_release(void **p, struct inode *inode,
865 				     int mds, int drop, int unless, int force);
866 extern int ceph_encode_dentry_release(void **p, struct dentry *dn,
867 				      int mds, int drop, int unless);
868 
869 extern int ceph_get_caps(struct ceph_inode_info *ci, int need, int want,
870 			 loff_t endoff, int *got, struct page **pinned_page);
871 
872 /* for counting open files by mode */
873 static inline void __ceph_get_fmode(struct ceph_inode_info *ci, int mode)
874 {
875 	ci->i_nr_by_mode[mode]++;
876 }
877 extern void ceph_put_fmode(struct ceph_inode_info *ci, int mode);
878 
879 /* addr.c */
880 extern const struct address_space_operations ceph_aops;
881 extern int ceph_mmap(struct file *file, struct vm_area_struct *vma);
882 
883 /* file.c */
884 extern const struct file_operations ceph_file_fops;
885 
886 extern int ceph_open(struct inode *inode, struct file *file);
887 extern int ceph_atomic_open(struct inode *dir, struct dentry *dentry,
888 			    struct file *file, unsigned flags, umode_t mode,
889 			    int *opened);
890 extern int ceph_release(struct inode *inode, struct file *filp);
891 extern void ceph_fill_inline_data(struct inode *inode, struct page *locked_page,
892 				  char *data, size_t len);
893 int ceph_uninline_data(struct file *filp, struct page *locked_page);
894 /* dir.c */
895 extern const struct file_operations ceph_dir_fops;
896 extern const struct file_operations ceph_snapdir_fops;
897 extern const struct inode_operations ceph_dir_iops;
898 extern const struct inode_operations ceph_snapdir_iops;
899 extern const struct dentry_operations ceph_dentry_ops, ceph_snap_dentry_ops,
900 	ceph_snapdir_dentry_ops;
901 
902 extern int ceph_handle_notrace_create(struct inode *dir, struct dentry *dentry);
903 extern int ceph_handle_snapdir(struct ceph_mds_request *req,
904 			       struct dentry *dentry, int err);
905 extern struct dentry *ceph_finish_lookup(struct ceph_mds_request *req,
906 					 struct dentry *dentry, int err);
907 
908 extern void ceph_dentry_lru_add(struct dentry *dn);
909 extern void ceph_dentry_lru_touch(struct dentry *dn);
910 extern void ceph_dentry_lru_del(struct dentry *dn);
911 extern void ceph_invalidate_dentry_lease(struct dentry *dentry);
912 extern unsigned ceph_dentry_hash(struct inode *dir, struct dentry *dn);
913 extern struct inode *ceph_get_dentry_parent_inode(struct dentry *dentry);
914 
915 /*
916  * our d_ops vary depending on whether the inode is live,
917  * snapshotted (read-only), or a virtual ".snap" directory.
918  */
919 int ceph_init_dentry(struct dentry *dentry);
920 
921 
922 /* ioctl.c */
923 extern long ceph_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
924 
925 /* export.c */
926 extern const struct export_operations ceph_export_ops;
927 
928 /* locks.c */
929 extern __init void ceph_flock_init(void);
930 extern int ceph_lock(struct file *file, int cmd, struct file_lock *fl);
931 extern int ceph_flock(struct file *file, int cmd, struct file_lock *fl);
932 extern void ceph_count_locks(struct inode *inode, int *p_num, int *f_num);
933 extern int ceph_encode_locks_to_buffer(struct inode *inode,
934 				       struct ceph_filelock *flocks,
935 				       int num_fcntl_locks,
936 				       int num_flock_locks);
937 extern int ceph_locks_to_pagelist(struct ceph_filelock *flocks,
938 				  struct ceph_pagelist *pagelist,
939 				  int num_fcntl_locks, int num_flock_locks);
940 extern int lock_to_ceph_filelock(struct file_lock *fl, struct ceph_filelock *c);
941 
942 /* debugfs.c */
943 extern int ceph_fs_debugfs_init(struct ceph_fs_client *client);
944 extern void ceph_fs_debugfs_cleanup(struct ceph_fs_client *client);
945 
946 #endif /* _FS_CEPH_SUPER_H */
947