xref: /openbmc/linux/fs/ceph/super.h (revision 861e10be)
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 
17 #include <linux/ceph/libceph.h>
18 
19 /* f_type in struct statfs */
20 #define CEPH_SUPER_MAGIC 0x00c36400
21 
22 /* large granularity for statfs utilization stats to facilitate
23  * large volume sizes on 32-bit machines. */
24 #define CEPH_BLOCK_SHIFT   20  /* 1 MB */
25 #define CEPH_BLOCK         (1 << CEPH_BLOCK_SHIFT)
26 
27 #define CEPH_MOUNT_OPT_DIRSTAT         (1<<4) /* `cat dirname` for stats */
28 #define CEPH_MOUNT_OPT_RBYTES          (1<<5) /* dir st_bytes = rbytes */
29 #define CEPH_MOUNT_OPT_NOASYNCREADDIR  (1<<7) /* no dcache readdir */
30 #define CEPH_MOUNT_OPT_INO32           (1<<8) /* 32 bit inos */
31 #define CEPH_MOUNT_OPT_DCACHE          (1<<9) /* use dcache for readdir etc */
32 
33 #define CEPH_MOUNT_OPT_DEFAULT    (CEPH_MOUNT_OPT_RBYTES)
34 
35 #define ceph_set_mount_opt(fsc, opt) \
36 	(fsc)->mount_options->flags |= CEPH_MOUNT_OPT_##opt;
37 #define ceph_test_mount_opt(fsc, opt) \
38 	(!!((fsc)->mount_options->flags & CEPH_MOUNT_OPT_##opt))
39 
40 #define CEPH_RSIZE_DEFAULT             0           /* max read size */
41 #define CEPH_RASIZE_DEFAULT            (8192*1024) /* readahead */
42 #define CEPH_MAX_READDIR_DEFAULT        1024
43 #define CEPH_MAX_READDIR_BYTES_DEFAULT  (512*1024)
44 #define CEPH_SNAPDIRNAME_DEFAULT        ".snap"
45 
46 struct ceph_mount_options {
47 	int flags;
48 	int sb_flags;
49 
50 	int wsize;            /* max write size */
51 	int rsize;            /* max read size */
52 	int rasize;           /* max readahead */
53 	int congestion_kb;    /* max writeback in flight */
54 	int caps_wanted_delay_min, caps_wanted_delay_max;
55 	int cap_release_safety;
56 	int max_readdir;       /* max readdir result (entires) */
57 	int max_readdir_bytes; /* max readdir result (bytes) */
58 
59 	/*
60 	 * everything above this point can be memcmp'd; everything below
61 	 * is handled in compare_mount_options()
62 	 */
63 
64 	char *snapdir_name;   /* default ".snap" */
65 };
66 
67 struct ceph_fs_client {
68 	struct super_block *sb;
69 
70 	struct ceph_mount_options *mount_options;
71 	struct ceph_client *client;
72 
73 	unsigned long mount_state;
74 	int min_caps;                  /* min caps i added */
75 
76 	struct ceph_mds_client *mdsc;
77 
78 	/* writeback */
79 	mempool_t *wb_pagevec_pool;
80 	struct workqueue_struct *wb_wq;
81 	struct workqueue_struct *pg_inv_wq;
82 	struct workqueue_struct *trunc_wq;
83 	atomic_long_t writeback_count;
84 
85 	struct backing_dev_info backing_dev_info;
86 
87 #ifdef CONFIG_DEBUG_FS
88 	struct dentry *debugfs_dentry_lru, *debugfs_caps;
89 	struct dentry *debugfs_congestion_kb;
90 	struct dentry *debugfs_bdi;
91 	struct dentry *debugfs_mdsc, *debugfs_mdsmap;
92 #endif
93 };
94 
95 
96 /*
97  * File i/o capability.  This tracks shared state with the metadata
98  * server that allows us to cache or writeback attributes or to read
99  * and write data.  For any given inode, we should have one or more
100  * capabilities, one issued by each metadata server, and our
101  * cumulative access is the OR of all issued capabilities.
102  *
103  * Each cap is referenced by the inode's i_caps rbtree and by per-mds
104  * session capability lists.
105  */
106 struct ceph_cap {
107 	struct ceph_inode_info *ci;
108 	struct rb_node ci_node;          /* per-ci cap tree */
109 	struct ceph_mds_session *session;
110 	struct list_head session_caps;   /* per-session caplist */
111 	int mds;
112 	u64 cap_id;       /* unique cap id (mds provided) */
113 	int issued;       /* latest, from the mds */
114 	int implemented;  /* implemented superset of issued (for revocation) */
115 	int mds_wanted;
116 	u32 seq, issue_seq, mseq;
117 	u32 cap_gen;      /* active/stale cycle */
118 	unsigned long last_used;
119 	struct list_head caps_item;
120 };
121 
122 #define CHECK_CAPS_NODELAY    1  /* do not delay any further */
123 #define CHECK_CAPS_AUTHONLY   2  /* only check auth cap */
124 #define CHECK_CAPS_FLUSH      4  /* flush any dirty caps */
125 
126 /*
127  * Snapped cap state that is pending flush to mds.  When a snapshot occurs,
128  * we first complete any in-process sync writes and writeback any dirty
129  * data before flushing the snapped state (tracked here) back to the MDS.
130  */
131 struct ceph_cap_snap {
132 	atomic_t nref;
133 	struct ceph_inode_info *ci;
134 	struct list_head ci_item, flushing_item;
135 
136 	u64 follows, flush_tid;
137 	int issued, dirty;
138 	struct ceph_snap_context *context;
139 
140 	umode_t mode;
141 	uid_t uid;
142 	gid_t gid;
143 
144 	struct ceph_buffer *xattr_blob;
145 	u64 xattr_version;
146 
147 	u64 size;
148 	struct timespec mtime, atime, ctime;
149 	u64 time_warp_seq;
150 	int writing;   /* a sync write is still in progress */
151 	int dirty_pages;     /* dirty pages awaiting writeback */
152 };
153 
154 static inline void ceph_put_cap_snap(struct ceph_cap_snap *capsnap)
155 {
156 	if (atomic_dec_and_test(&capsnap->nref)) {
157 		if (capsnap->xattr_blob)
158 			ceph_buffer_put(capsnap->xattr_blob);
159 		kfree(capsnap);
160 	}
161 }
162 
163 /*
164  * The frag tree describes how a directory is fragmented, potentially across
165  * multiple metadata servers.  It is also used to indicate points where
166  * metadata authority is delegated, and whether/where metadata is replicated.
167  *
168  * A _leaf_ frag will be present in the i_fragtree IFF there is
169  * delegation info.  That is, if mds >= 0 || ndist > 0.
170  */
171 #define CEPH_MAX_DIRFRAG_REP 4
172 
173 struct ceph_inode_frag {
174 	struct rb_node node;
175 
176 	/* fragtree state */
177 	u32 frag;
178 	int split_by;         /* i.e. 2^(split_by) children */
179 
180 	/* delegation and replication info */
181 	int mds;              /* -1 if same authority as parent */
182 	int ndist;            /* >0 if replicated */
183 	int dist[CEPH_MAX_DIRFRAG_REP];
184 };
185 
186 /*
187  * We cache inode xattrs as an encoded blob until they are first used,
188  * at which point we parse them into an rbtree.
189  */
190 struct ceph_inode_xattr {
191 	struct rb_node node;
192 
193 	const char *name;
194 	int name_len;
195 	const char *val;
196 	int val_len;
197 	int dirty;
198 
199 	int should_free_name;
200 	int should_free_val;
201 };
202 
203 /*
204  * Ceph dentry state
205  */
206 struct ceph_dentry_info {
207 	unsigned long flags;
208 	struct ceph_mds_session *lease_session;
209 	u32 lease_gen, lease_shared_gen;
210 	u32 lease_seq;
211 	unsigned long lease_renew_after, lease_renew_from;
212 	struct list_head lru;
213 	struct dentry *dentry;
214 	u64 time;
215 	u64 offset;
216 };
217 
218 /*
219  * dentry flags
220  *
221  * The locking for D_COMPLETE is a bit odd:
222  *  - we can clear it at almost any time (see ceph_d_prune)
223  *  - it is only meaningful if:
224  *    - we hold dir inode i_ceph_lock
225  *    - we hold dir FILE_SHARED caps
226  *    - the dentry D_COMPLETE is set
227  */
228 #define CEPH_D_COMPLETE 1  /* if set, d_u.d_subdirs is complete directory */
229 
230 struct ceph_inode_xattrs_info {
231 	/*
232 	 * (still encoded) xattr blob. we avoid the overhead of parsing
233 	 * this until someone actually calls getxattr, etc.
234 	 *
235 	 * blob->vec.iov_len == 4 implies there are no xattrs; blob ==
236 	 * NULL means we don't know.
237 	*/
238 	struct ceph_buffer *blob, *prealloc_blob;
239 
240 	struct rb_root index;
241 	bool dirty;
242 	int count;
243 	int names_size;
244 	int vals_size;
245 	u64 version, index_version;
246 };
247 
248 /*
249  * Ceph inode.
250  */
251 struct ceph_inode_info {
252 	struct ceph_vino i_vino;   /* ceph ino + snap */
253 
254 	spinlock_t i_ceph_lock;
255 
256 	u64 i_version;
257 	u32 i_time_warp_seq;
258 
259 	unsigned i_ceph_flags;
260 	unsigned long i_release_count;
261 
262 	struct ceph_dir_layout i_dir_layout;
263 	struct ceph_file_layout i_layout;
264 	char *i_symlink;
265 
266 	/* for dirs */
267 	struct timespec i_rctime;
268 	u64 i_rbytes, i_rfiles, i_rsubdirs;
269 	u64 i_files, i_subdirs;
270 	u64 i_max_offset;  /* largest readdir offset, set with D_COMPLETE */
271 
272 	struct rb_root i_fragtree;
273 	struct mutex i_fragtree_mutex;
274 
275 	struct ceph_inode_xattrs_info i_xattrs;
276 
277 	/* capabilities.  protected _both_ by i_ceph_lock and cap->session's
278 	 * s_mutex. */
279 	struct rb_root i_caps;           /* cap list */
280 	struct ceph_cap *i_auth_cap;     /* authoritative cap, if any */
281 	unsigned i_dirty_caps, i_flushing_caps;     /* mask of dirtied fields */
282 	struct list_head i_dirty_item, i_flushing_item;
283 	u64 i_cap_flush_seq;
284 	/* we need to track cap writeback on a per-cap-bit basis, to allow
285 	 * overlapping, pipelined cap flushes to the mds.  we can probably
286 	 * reduce the tid to 8 bits if we're concerned about inode size. */
287 	u16 i_cap_flush_last_tid, i_cap_flush_tid[CEPH_CAP_BITS];
288 	wait_queue_head_t i_cap_wq;      /* threads waiting on a capability */
289 	unsigned long i_hold_caps_min; /* jiffies */
290 	unsigned long i_hold_caps_max; /* jiffies */
291 	struct list_head i_cap_delay_list;  /* for delayed cap release to mds */
292 	int i_cap_exporting_mds;         /* to handle cap migration between */
293 	unsigned i_cap_exporting_mseq;   /*  mds's. */
294 	unsigned i_cap_exporting_issued;
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 	u32 i_truncate_seq;        /* last truncate to smaller size */
304 	u64 i_truncate_size;       /*  and the size we last truncated down to */
305 	int i_truncate_pending;    /*  still need to call vmtruncate */
306 
307 	u64 i_max_size;            /* max file size authorized by mds */
308 	u64 i_reported_size; /* (max_)size reported to or requested of mds */
309 	u64 i_wanted_max_size;     /* offset we'd like to write too */
310 	u64 i_requested_max_size;  /* max_size we've requested */
311 
312 	/* held references to caps */
313 	int i_pin_ref;
314 	int i_rd_ref, i_rdcache_ref, i_wr_ref, i_wb_ref;
315 	int i_wrbuffer_ref, i_wrbuffer_ref_head;
316 	u32 i_shared_gen;       /* increment each time we get FILE_SHARED */
317 	u32 i_rdcache_gen;      /* incremented each time we get FILE_CACHE. */
318 	u32 i_rdcache_revoking; /* RDCACHE gen to async invalidate, if any */
319 
320 	struct list_head i_unsafe_writes; /* uncommitted sync writes */
321 	struct list_head i_unsafe_dirops; /* uncommitted mds dir ops */
322 	spinlock_t i_unsafe_lock;
323 
324 	struct ceph_snap_realm *i_snap_realm; /* snap realm (if caps) */
325 	int i_snap_realm_counter; /* snap realm (if caps) */
326 	struct list_head i_snap_realm_item;
327 	struct list_head i_snap_flush_item;
328 
329 	struct work_struct i_wb_work;  /* writeback work */
330 	struct work_struct i_pg_inv_work;  /* page invalidation work */
331 
332 	struct work_struct i_vmtruncate_work;
333 
334 	struct inode vfs_inode; /* at end */
335 };
336 
337 static inline struct ceph_inode_info *ceph_inode(struct inode *inode)
338 {
339 	return container_of(inode, struct ceph_inode_info, vfs_inode);
340 }
341 
342 static inline struct ceph_fs_client *ceph_inode_to_client(struct inode *inode)
343 {
344 	return (struct ceph_fs_client *)inode->i_sb->s_fs_info;
345 }
346 
347 static inline struct ceph_fs_client *ceph_sb_to_client(struct super_block *sb)
348 {
349 	return (struct ceph_fs_client *)sb->s_fs_info;
350 }
351 
352 static inline struct ceph_vino ceph_vino(struct inode *inode)
353 {
354 	return ceph_inode(inode)->i_vino;
355 }
356 
357 /*
358  * ino_t is <64 bits on many architectures, blech.
359  *
360  *               i_ino (kernel inode)   st_ino (userspace)
361  * i386          32                     32
362  * x86_64+ino32  64                     32
363  * x86_64        64                     64
364  */
365 static inline u32 ceph_ino_to_ino32(__u64 vino)
366 {
367 	u32 ino = vino & 0xffffffff;
368 	ino ^= vino >> 32;
369 	if (!ino)
370 		ino = 2;
371 	return ino;
372 }
373 
374 /*
375  * kernel i_ino value
376  */
377 static inline ino_t ceph_vino_to_ino(struct ceph_vino vino)
378 {
379 #if BITS_PER_LONG == 32
380 	return ceph_ino_to_ino32(vino.ino);
381 #else
382 	return (ino_t)vino.ino;
383 #endif
384 }
385 
386 /*
387  * user-visible ino (stat, filldir)
388  */
389 #if BITS_PER_LONG == 32
390 static inline ino_t ceph_translate_ino(struct super_block *sb, ino_t ino)
391 {
392 	return ino;
393 }
394 #else
395 static inline ino_t ceph_translate_ino(struct super_block *sb, ino_t ino)
396 {
397 	if (ceph_test_mount_opt(ceph_sb_to_client(sb), INO32))
398 		ino = ceph_ino_to_ino32(ino);
399 	return ino;
400 }
401 #endif
402 
403 
404 /* for printf-style formatting */
405 #define ceph_vinop(i) ceph_inode(i)->i_vino.ino, ceph_inode(i)->i_vino.snap
406 
407 static inline u64 ceph_ino(struct inode *inode)
408 {
409 	return ceph_inode(inode)->i_vino.ino;
410 }
411 static inline u64 ceph_snap(struct inode *inode)
412 {
413 	return ceph_inode(inode)->i_vino.snap;
414 }
415 
416 static inline int ceph_ino_compare(struct inode *inode, void *data)
417 {
418 	struct ceph_vino *pvino = (struct ceph_vino *)data;
419 	struct ceph_inode_info *ci = ceph_inode(inode);
420 	return ci->i_vino.ino == pvino->ino &&
421 		ci->i_vino.snap == pvino->snap;
422 }
423 
424 static inline struct inode *ceph_find_inode(struct super_block *sb,
425 					    struct ceph_vino vino)
426 {
427 	ino_t t = ceph_vino_to_ino(vino);
428 	return ilookup5(sb, t, ceph_ino_compare, &vino);
429 }
430 
431 
432 /*
433  * Ceph inode.
434  */
435 #define CEPH_I_NODELAY   4  /* do not delay cap release */
436 #define CEPH_I_FLUSH     8  /* do not delay flush of dirty metadata */
437 #define CEPH_I_NOFLUSH  16  /* do not flush dirty caps */
438 
439 static inline void ceph_i_clear(struct inode *inode, unsigned mask)
440 {
441 	struct ceph_inode_info *ci = ceph_inode(inode);
442 
443 	spin_lock(&ci->i_ceph_lock);
444 	ci->i_ceph_flags &= ~mask;
445 	spin_unlock(&ci->i_ceph_lock);
446 }
447 
448 static inline void ceph_i_set(struct inode *inode, unsigned mask)
449 {
450 	struct ceph_inode_info *ci = ceph_inode(inode);
451 
452 	spin_lock(&ci->i_ceph_lock);
453 	ci->i_ceph_flags |= mask;
454 	spin_unlock(&ci->i_ceph_lock);
455 }
456 
457 static inline bool ceph_i_test(struct inode *inode, unsigned mask)
458 {
459 	struct ceph_inode_info *ci = ceph_inode(inode);
460 	bool r;
461 
462 	spin_lock(&ci->i_ceph_lock);
463 	r = (ci->i_ceph_flags & mask) == mask;
464 	spin_unlock(&ci->i_ceph_lock);
465 	return r;
466 }
467 
468 
469 /* find a specific frag @f */
470 extern struct ceph_inode_frag *__ceph_find_frag(struct ceph_inode_info *ci,
471 						u32 f);
472 
473 /*
474  * choose fragment for value @v.  copy frag content to pfrag, if leaf
475  * exists
476  */
477 extern u32 ceph_choose_frag(struct ceph_inode_info *ci, u32 v,
478 			    struct ceph_inode_frag *pfrag,
479 			    int *found);
480 
481 static inline struct ceph_dentry_info *ceph_dentry(struct dentry *dentry)
482 {
483 	return (struct ceph_dentry_info *)dentry->d_fsdata;
484 }
485 
486 static inline loff_t ceph_make_fpos(unsigned frag, unsigned off)
487 {
488 	return ((loff_t)frag << 32) | (loff_t)off;
489 }
490 
491 /*
492  * set/clear directory D_COMPLETE flag
493  */
494 void ceph_dir_set_complete(struct inode *inode);
495 void ceph_dir_clear_complete(struct inode *inode);
496 bool ceph_dir_test_complete(struct inode *inode);
497 
498 /*
499  * caps helpers
500  */
501 static inline bool __ceph_is_any_real_caps(struct ceph_inode_info *ci)
502 {
503 	return !RB_EMPTY_ROOT(&ci->i_caps);
504 }
505 
506 extern int __ceph_caps_issued(struct ceph_inode_info *ci, int *implemented);
507 extern int __ceph_caps_issued_mask(struct ceph_inode_info *ci, int mask, int t);
508 extern int __ceph_caps_issued_other(struct ceph_inode_info *ci,
509 				    struct ceph_cap *cap);
510 
511 static inline int ceph_caps_issued(struct ceph_inode_info *ci)
512 {
513 	int issued;
514 	spin_lock(&ci->i_ceph_lock);
515 	issued = __ceph_caps_issued(ci, NULL);
516 	spin_unlock(&ci->i_ceph_lock);
517 	return issued;
518 }
519 
520 static inline int ceph_caps_issued_mask(struct ceph_inode_info *ci, int mask,
521 					int touch)
522 {
523 	int r;
524 	spin_lock(&ci->i_ceph_lock);
525 	r = __ceph_caps_issued_mask(ci, mask, touch);
526 	spin_unlock(&ci->i_ceph_lock);
527 	return r;
528 }
529 
530 static inline int __ceph_caps_dirty(struct ceph_inode_info *ci)
531 {
532 	return ci->i_dirty_caps | ci->i_flushing_caps;
533 }
534 extern int __ceph_mark_dirty_caps(struct ceph_inode_info *ci, int mask);
535 
536 extern int ceph_caps_revoking(struct ceph_inode_info *ci, int mask);
537 extern int __ceph_caps_used(struct ceph_inode_info *ci);
538 
539 extern int __ceph_caps_file_wanted(struct ceph_inode_info *ci);
540 
541 /*
542  * wanted, by virtue of open file modes AND cap refs (buffered/cached data)
543  */
544 static inline int __ceph_caps_wanted(struct ceph_inode_info *ci)
545 {
546 	int w = __ceph_caps_file_wanted(ci) | __ceph_caps_used(ci);
547 	if (w & CEPH_CAP_FILE_BUFFER)
548 		w |= CEPH_CAP_FILE_EXCL;  /* we want EXCL if dirty data */
549 	return w;
550 }
551 
552 /* what the mds thinks we want */
553 extern int __ceph_caps_mds_wanted(struct ceph_inode_info *ci);
554 
555 extern void ceph_caps_init(struct ceph_mds_client *mdsc);
556 extern void ceph_caps_finalize(struct ceph_mds_client *mdsc);
557 extern void ceph_adjust_min_caps(struct ceph_mds_client *mdsc, int delta);
558 extern int ceph_reserve_caps(struct ceph_mds_client *mdsc,
559 			     struct ceph_cap_reservation *ctx, int need);
560 extern int ceph_unreserve_caps(struct ceph_mds_client *mdsc,
561 			       struct ceph_cap_reservation *ctx);
562 extern void ceph_reservation_status(struct ceph_fs_client *client,
563 				    int *total, int *avail, int *used,
564 				    int *reserved, int *min);
565 
566 
567 
568 /*
569  * we keep buffered readdir results attached to file->private_data
570  */
571 #define CEPH_F_SYNC     1
572 #define CEPH_F_ATEND    2
573 
574 struct ceph_file_info {
575 	short fmode;     /* initialized on open */
576 	short flags;     /* CEPH_F_* */
577 
578 	/* readdir: position within the dir */
579 	u32 frag;
580 	struct ceph_mds_request *last_readdir;
581 
582 	/* readdir: position within a frag */
583 	unsigned offset;       /* offset of last chunk, adjusted for . and .. */
584 	u64 next_offset;       /* offset of next chunk (last_name's + 1) */
585 	char *last_name;       /* last entry in previous chunk */
586 	struct dentry *dentry; /* next dentry (for dcache readdir) */
587 	unsigned long dir_release_count;
588 
589 	/* used for -o dirstat read() on directory thing */
590 	char *dir_info;
591 	int dir_info_len;
592 };
593 
594 
595 
596 /*
597  * A "snap realm" describes a subset of the file hierarchy sharing
598  * the same set of snapshots that apply to it.  The realms themselves
599  * are organized into a hierarchy, such that children inherit (some of)
600  * the snapshots of their parents.
601  *
602  * All inodes within the realm that have capabilities are linked into a
603  * per-realm list.
604  */
605 struct ceph_snap_realm {
606 	u64 ino;
607 	atomic_t nref;
608 	struct rb_node node;
609 
610 	u64 created, seq;
611 	u64 parent_ino;
612 	u64 parent_since;   /* snapid when our current parent became so */
613 
614 	u64 *prior_parent_snaps;      /* snaps inherited from any parents we */
615 	u32 num_prior_parent_snaps;   /*  had prior to parent_since */
616 	u64 *snaps;                   /* snaps specific to this realm */
617 	u32 num_snaps;
618 
619 	struct ceph_snap_realm *parent;
620 	struct list_head children;       /* list of child realms */
621 	struct list_head child_item;
622 
623 	struct list_head empty_item;     /* if i have ref==0 */
624 
625 	struct list_head dirty_item;     /* if realm needs new context */
626 
627 	/* the current set of snaps for this realm */
628 	struct ceph_snap_context *cached_context;
629 
630 	struct list_head inodes_with_caps;
631 	spinlock_t inodes_with_caps_lock;
632 };
633 
634 static inline int default_congestion_kb(void)
635 {
636 	int congestion_kb;
637 
638 	/*
639 	 * Copied from NFS
640 	 *
641 	 * congestion size, scale with available memory.
642 	 *
643 	 *  64MB:    8192k
644 	 * 128MB:   11585k
645 	 * 256MB:   16384k
646 	 * 512MB:   23170k
647 	 *   1GB:   32768k
648 	 *   2GB:   46340k
649 	 *   4GB:   65536k
650 	 *   8GB:   92681k
651 	 *  16GB:  131072k
652 	 *
653 	 * This allows larger machines to have larger/more transfers.
654 	 * Limit the default to 256M
655 	 */
656 	congestion_kb = (16*int_sqrt(totalram_pages)) << (PAGE_SHIFT-10);
657 	if (congestion_kb > 256*1024)
658 		congestion_kb = 256*1024;
659 
660 	return congestion_kb;
661 }
662 
663 
664 
665 /* snap.c */
666 struct ceph_snap_realm *ceph_lookup_snap_realm(struct ceph_mds_client *mdsc,
667 					       u64 ino);
668 extern void ceph_get_snap_realm(struct ceph_mds_client *mdsc,
669 				struct ceph_snap_realm *realm);
670 extern void ceph_put_snap_realm(struct ceph_mds_client *mdsc,
671 				struct ceph_snap_realm *realm);
672 extern int ceph_update_snap_trace(struct ceph_mds_client *m,
673 				  void *p, void *e, bool deletion);
674 extern void ceph_handle_snap(struct ceph_mds_client *mdsc,
675 			     struct ceph_mds_session *session,
676 			     struct ceph_msg *msg);
677 extern void ceph_queue_cap_snap(struct ceph_inode_info *ci);
678 extern int __ceph_finish_cap_snap(struct ceph_inode_info *ci,
679 				  struct ceph_cap_snap *capsnap);
680 extern void ceph_cleanup_empty_realms(struct ceph_mds_client *mdsc);
681 
682 /*
683  * a cap_snap is "pending" if it is still awaiting an in-progress
684  * sync write (that may/may not still update size, mtime, etc.).
685  */
686 static inline bool __ceph_have_pending_cap_snap(struct ceph_inode_info *ci)
687 {
688 	return !list_empty(&ci->i_cap_snaps) &&
689 		list_entry(ci->i_cap_snaps.prev, struct ceph_cap_snap,
690 			   ci_item)->writing;
691 }
692 
693 /* inode.c */
694 extern const struct inode_operations ceph_file_iops;
695 
696 extern struct inode *ceph_alloc_inode(struct super_block *sb);
697 extern void ceph_destroy_inode(struct inode *inode);
698 
699 extern struct inode *ceph_get_inode(struct super_block *sb,
700 				    struct ceph_vino vino);
701 extern struct inode *ceph_get_snapdir(struct inode *parent);
702 extern int ceph_fill_file_size(struct inode *inode, int issued,
703 			       u32 truncate_seq, u64 truncate_size, u64 size);
704 extern void ceph_fill_file_time(struct inode *inode, int issued,
705 				u64 time_warp_seq, struct timespec *ctime,
706 				struct timespec *mtime, struct timespec *atime);
707 extern int ceph_fill_trace(struct super_block *sb,
708 			   struct ceph_mds_request *req,
709 			   struct ceph_mds_session *session);
710 extern int ceph_readdir_prepopulate(struct ceph_mds_request *req,
711 				    struct ceph_mds_session *session);
712 
713 extern int ceph_inode_holds_cap(struct inode *inode, int mask);
714 
715 extern int ceph_inode_set_size(struct inode *inode, loff_t size);
716 extern void __ceph_do_pending_vmtruncate(struct inode *inode);
717 extern void ceph_queue_vmtruncate(struct inode *inode);
718 
719 extern void ceph_queue_invalidate(struct inode *inode);
720 extern void ceph_queue_writeback(struct inode *inode);
721 
722 extern int ceph_do_getattr(struct inode *inode, int mask);
723 extern int ceph_permission(struct inode *inode, int mask);
724 extern int ceph_setattr(struct dentry *dentry, struct iattr *attr);
725 extern int ceph_getattr(struct vfsmount *mnt, struct dentry *dentry,
726 			struct kstat *stat);
727 
728 /* xattr.c */
729 extern int ceph_setxattr(struct dentry *, const char *, const void *,
730 			 size_t, int);
731 extern ssize_t ceph_getxattr(struct dentry *, const char *, void *, size_t);
732 extern ssize_t ceph_listxattr(struct dentry *, char *, size_t);
733 extern int ceph_removexattr(struct dentry *, const char *);
734 extern void __ceph_build_xattrs_blob(struct ceph_inode_info *ci);
735 extern void __ceph_destroy_xattrs(struct ceph_inode_info *ci);
736 extern void __init ceph_xattr_init(void);
737 extern void ceph_xattr_exit(void);
738 
739 /* caps.c */
740 extern const char *ceph_cap_string(int c);
741 extern void ceph_handle_caps(struct ceph_mds_session *session,
742 			     struct ceph_msg *msg);
743 extern int ceph_add_cap(struct inode *inode,
744 			struct ceph_mds_session *session, u64 cap_id,
745 			int fmode, unsigned issued, unsigned wanted,
746 			unsigned cap, unsigned seq, u64 realmino, int flags,
747 			struct ceph_cap_reservation *caps_reservation);
748 extern void __ceph_remove_cap(struct ceph_cap *cap);
749 static inline void ceph_remove_cap(struct ceph_cap *cap)
750 {
751 	spin_lock(&cap->ci->i_ceph_lock);
752 	__ceph_remove_cap(cap);
753 	spin_unlock(&cap->ci->i_ceph_lock);
754 }
755 extern void ceph_put_cap(struct ceph_mds_client *mdsc,
756 			 struct ceph_cap *cap);
757 
758 extern void ceph_queue_caps_release(struct inode *inode);
759 extern int ceph_write_inode(struct inode *inode, struct writeback_control *wbc);
760 extern int ceph_fsync(struct file *file, loff_t start, loff_t end,
761 		      int datasync);
762 extern void ceph_kick_flushing_caps(struct ceph_mds_client *mdsc,
763 				    struct ceph_mds_session *session);
764 extern struct ceph_cap *ceph_get_cap_for_mds(struct ceph_inode_info *ci,
765 					     int mds);
766 extern int ceph_get_cap_mds(struct inode *inode);
767 extern void ceph_get_cap_refs(struct ceph_inode_info *ci, int caps);
768 extern void ceph_put_cap_refs(struct ceph_inode_info *ci, int had);
769 extern void ceph_put_wrbuffer_cap_refs(struct ceph_inode_info *ci, int nr,
770 				       struct ceph_snap_context *snapc);
771 extern void __ceph_flush_snaps(struct ceph_inode_info *ci,
772 			       struct ceph_mds_session **psession,
773 			       int again);
774 extern void ceph_check_caps(struct ceph_inode_info *ci, int flags,
775 			    struct ceph_mds_session *session);
776 extern void ceph_check_delayed_caps(struct ceph_mds_client *mdsc);
777 extern void ceph_flush_dirty_caps(struct ceph_mds_client *mdsc);
778 
779 extern int ceph_encode_inode_release(void **p, struct inode *inode,
780 				     int mds, int drop, int unless, int force);
781 extern int ceph_encode_dentry_release(void **p, struct dentry *dn,
782 				      int mds, int drop, int unless);
783 
784 extern int ceph_get_caps(struct ceph_inode_info *ci, int need, int want,
785 			 int *got, loff_t endoff);
786 
787 /* for counting open files by mode */
788 static inline void __ceph_get_fmode(struct ceph_inode_info *ci, int mode)
789 {
790 	ci->i_nr_by_mode[mode]++;
791 }
792 extern void ceph_put_fmode(struct ceph_inode_info *ci, int mode);
793 
794 /* addr.c */
795 extern const struct address_space_operations ceph_aops;
796 extern int ceph_mmap(struct file *file, struct vm_area_struct *vma);
797 
798 /* file.c */
799 extern const struct file_operations ceph_file_fops;
800 extern const struct address_space_operations ceph_aops;
801 extern int ceph_copy_to_page_vector(struct page **pages,
802 				    const char *data,
803 				    loff_t off, size_t len);
804 extern int ceph_copy_from_page_vector(struct page **pages,
805 				    char *data,
806 				    loff_t off, size_t len);
807 extern struct page **ceph_alloc_page_vector(int num_pages, gfp_t flags);
808 extern int ceph_open(struct inode *inode, struct file *file);
809 extern int ceph_atomic_open(struct inode *dir, struct dentry *dentry,
810 			    struct file *file, unsigned flags, umode_t mode,
811 			    int *opened);
812 extern int ceph_release(struct inode *inode, struct file *filp);
813 
814 /* dir.c */
815 extern const struct file_operations ceph_dir_fops;
816 extern const struct inode_operations ceph_dir_iops;
817 extern const struct dentry_operations ceph_dentry_ops, ceph_snap_dentry_ops,
818 	ceph_snapdir_dentry_ops;
819 
820 extern int ceph_handle_notrace_create(struct inode *dir, struct dentry *dentry);
821 extern int ceph_handle_snapdir(struct ceph_mds_request *req,
822 			       struct dentry *dentry, int err);
823 extern struct dentry *ceph_finish_lookup(struct ceph_mds_request *req,
824 					 struct dentry *dentry, int err);
825 
826 extern void ceph_dentry_lru_add(struct dentry *dn);
827 extern void ceph_dentry_lru_touch(struct dentry *dn);
828 extern void ceph_dentry_lru_del(struct dentry *dn);
829 extern void ceph_invalidate_dentry_lease(struct dentry *dentry);
830 extern unsigned ceph_dentry_hash(struct inode *dir, struct dentry *dn);
831 extern struct inode *ceph_get_dentry_parent_inode(struct dentry *dentry);
832 
833 /*
834  * our d_ops vary depending on whether the inode is live,
835  * snapshotted (read-only), or a virtual ".snap" directory.
836  */
837 int ceph_init_dentry(struct dentry *dentry);
838 
839 
840 /* ioctl.c */
841 extern long ceph_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
842 
843 /* export.c */
844 extern const struct export_operations ceph_export_ops;
845 
846 /* locks.c */
847 extern int ceph_lock(struct file *file, int cmd, struct file_lock *fl);
848 extern int ceph_flock(struct file *file, int cmd, struct file_lock *fl);
849 extern void ceph_count_locks(struct inode *inode, int *p_num, int *f_num);
850 extern int ceph_encode_locks(struct inode *i, struct ceph_pagelist *p,
851 			     int p_locks, int f_locks);
852 extern int lock_to_ceph_filelock(struct file_lock *fl, struct ceph_filelock *c);
853 
854 /* debugfs.c */
855 extern int ceph_fs_debugfs_init(struct ceph_fs_client *client);
856 extern void ceph_fs_debugfs_cleanup(struct ceph_fs_client *client);
857 
858 #endif /* _FS_CEPH_SUPER_H */
859