xref: /linux/fs/ceph/super.h (revision 424f0750edd5af866f80f5e65998e0610503cb5c)
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 
32 #define CEPH_MOUNT_OPT_DEFAULT    (CEPH_MOUNT_OPT_RBYTES)
33 
34 #define ceph_set_mount_opt(fsc, opt) \
35 	(fsc)->mount_options->flags |= CEPH_MOUNT_OPT_##opt;
36 #define ceph_test_mount_opt(fsc, opt) \
37 	(!!((fsc)->mount_options->flags & CEPH_MOUNT_OPT_##opt))
38 
39 #define CEPH_RSIZE_DEFAULT             0           /* max read size */
40 #define CEPH_RASIZE_DEFAULT            (8192*1024) /* readahead */
41 #define CEPH_MAX_READDIR_DEFAULT        1024
42 #define CEPH_MAX_READDIR_BYTES_DEFAULT  (512*1024)
43 #define CEPH_SNAPDIRNAME_DEFAULT        ".snap"
44 
45 struct ceph_mount_options {
46 	int flags;
47 	int sb_flags;
48 
49 	int wsize;            /* max write size */
50 	int rsize;            /* max read size */
51 	int rasize;           /* max readahead */
52 	int congestion_kb;    /* max writeback in flight */
53 	int caps_wanted_delay_min, caps_wanted_delay_max;
54 	int cap_release_safety;
55 	int max_readdir;       /* max readdir result (entires) */
56 	int max_readdir_bytes; /* max readdir result (bytes) */
57 
58 	/*
59 	 * everything above this point can be memcmp'd; everything below
60 	 * is handled in compare_mount_options()
61 	 */
62 
63 	char *snapdir_name;   /* default ".snap" */
64 };
65 
66 struct ceph_fs_client {
67 	struct super_block *sb;
68 
69 	struct ceph_mount_options *mount_options;
70 	struct ceph_client *client;
71 
72 	unsigned long mount_state;
73 	int min_caps;                  /* min caps i added */
74 
75 	struct ceph_mds_client *mdsc;
76 
77 	/* writeback */
78 	mempool_t *wb_pagevec_pool;
79 	struct workqueue_struct *wb_wq;
80 	struct workqueue_struct *pg_inv_wq;
81 	struct workqueue_struct *trunc_wq;
82 	atomic_long_t writeback_count;
83 
84 	struct backing_dev_info backing_dev_info;
85 
86 #ifdef CONFIG_DEBUG_FS
87 	struct dentry *debugfs_dentry_lru, *debugfs_caps;
88 	struct dentry *debugfs_congestion_kb;
89 	struct dentry *debugfs_bdi;
90 	struct dentry *debugfs_mdsc, *debugfs_mdsmap;
91 #endif
92 };
93 
94 
95 /*
96  * File i/o capability.  This tracks shared state with the metadata
97  * server that allows us to cache or writeback attributes or to read
98  * and write data.  For any given inode, we should have one or more
99  * capabilities, one issued by each metadata server, and our
100  * cumulative access is the OR of all issued capabilities.
101  *
102  * Each cap is referenced by the inode's i_caps rbtree and by per-mds
103  * session capability lists.
104  */
105 struct ceph_cap {
106 	struct ceph_inode_info *ci;
107 	struct rb_node ci_node;          /* per-ci cap tree */
108 	struct ceph_mds_session *session;
109 	struct list_head session_caps;   /* per-session caplist */
110 	int mds;
111 	u64 cap_id;       /* unique cap id (mds provided) */
112 	int issued;       /* latest, from the mds */
113 	int implemented;  /* implemented superset of issued (for revocation) */
114 	int mds_wanted;
115 	u32 seq, issue_seq, mseq;
116 	u32 cap_gen;      /* active/stale cycle */
117 	unsigned long last_used;
118 	struct list_head caps_item;
119 };
120 
121 #define CHECK_CAPS_NODELAY    1  /* do not delay any further */
122 #define CHECK_CAPS_AUTHONLY   2  /* only check auth cap */
123 #define CHECK_CAPS_FLUSH      4  /* flush any dirty caps */
124 
125 /*
126  * Snapped cap state that is pending flush to mds.  When a snapshot occurs,
127  * we first complete any in-process sync writes and writeback any dirty
128  * data before flushing the snapped state (tracked here) back to the MDS.
129  */
130 struct ceph_cap_snap {
131 	atomic_t nref;
132 	struct ceph_inode_info *ci;
133 	struct list_head ci_item, flushing_item;
134 
135 	u64 follows, flush_tid;
136 	int issued, dirty;
137 	struct ceph_snap_context *context;
138 
139 	mode_t mode;
140 	uid_t uid;
141 	gid_t gid;
142 
143 	struct ceph_buffer *xattr_blob;
144 	u64 xattr_version;
145 
146 	u64 size;
147 	struct timespec mtime, atime, ctime;
148 	u64 time_warp_seq;
149 	int writing;   /* a sync write is still in progress */
150 	int dirty_pages;     /* dirty pages awaiting writeback */
151 };
152 
153 static inline void ceph_put_cap_snap(struct ceph_cap_snap *capsnap)
154 {
155 	if (atomic_dec_and_test(&capsnap->nref)) {
156 		if (capsnap->xattr_blob)
157 			ceph_buffer_put(capsnap->xattr_blob);
158 		kfree(capsnap);
159 	}
160 }
161 
162 /*
163  * The frag tree describes how a directory is fragmented, potentially across
164  * multiple metadata servers.  It is also used to indicate points where
165  * metadata authority is delegated, and whether/where metadata is replicated.
166  *
167  * A _leaf_ frag will be present in the i_fragtree IFF there is
168  * delegation info.  That is, if mds >= 0 || ndist > 0.
169  */
170 #define CEPH_MAX_DIRFRAG_REP 4
171 
172 struct ceph_inode_frag {
173 	struct rb_node node;
174 
175 	/* fragtree state */
176 	u32 frag;
177 	int split_by;         /* i.e. 2^(split_by) children */
178 
179 	/* delegation and replication info */
180 	int mds;              /* -1 if same authority as parent */
181 	int ndist;            /* >0 if replicated */
182 	int dist[CEPH_MAX_DIRFRAG_REP];
183 };
184 
185 /*
186  * We cache inode xattrs as an encoded blob until they are first used,
187  * at which point we parse them into an rbtree.
188  */
189 struct ceph_inode_xattr {
190 	struct rb_node node;
191 
192 	const char *name;
193 	int name_len;
194 	const char *val;
195 	int val_len;
196 	int dirty;
197 
198 	int should_free_name;
199 	int should_free_val;
200 };
201 
202 /*
203  * Ceph dentry state
204  */
205 struct ceph_dentry_info {
206 	unsigned long flags;
207 	struct ceph_mds_session *lease_session;
208 	u32 lease_gen, lease_shared_gen;
209 	u32 lease_seq;
210 	unsigned long lease_renew_after, lease_renew_from;
211 	struct list_head lru;
212 	struct dentry *dentry;
213 	u64 time;
214 	u64 offset;
215 };
216 
217 /*
218  * dentry flags
219  *
220  * The locking for D_COMPLETE is a bit odd:
221  *  - we can clear it at almost any time (see ceph_d_prune)
222  *  - it is only meaningful if:
223  *    - we hold dir inode i_lock
224  *    - we hold dir FILE_SHARED caps
225  *    - the dentry D_COMPLETE is set
226  */
227 #define CEPH_D_COMPLETE 1  /* if set, d_u.d_subdirs is complete directory */
228 
229 struct ceph_inode_xattrs_info {
230 	/*
231 	 * (still encoded) xattr blob. we avoid the overhead of parsing
232 	 * this until someone actually calls getxattr, etc.
233 	 *
234 	 * blob->vec.iov_len == 4 implies there are no xattrs; blob ==
235 	 * NULL means we don't know.
236 	*/
237 	struct ceph_buffer *blob, *prealloc_blob;
238 
239 	struct rb_root index;
240 	bool dirty;
241 	int count;
242 	int names_size;
243 	int vals_size;
244 	u64 version, index_version;
245 };
246 
247 /*
248  * Ceph inode.
249  */
250 struct ceph_inode_info {
251 	struct ceph_vino i_vino;   /* ceph ino + snap */
252 
253 	u64 i_version;
254 	u32 i_time_warp_seq;
255 
256 	unsigned i_ceph_flags;
257 	unsigned long i_release_count;
258 
259 	struct ceph_dir_layout i_dir_layout;
260 	struct ceph_file_layout i_layout;
261 	char *i_symlink;
262 
263 	/* for dirs */
264 	struct timespec i_rctime;
265 	u64 i_rbytes, i_rfiles, i_rsubdirs;
266 	u64 i_files, i_subdirs;
267 	u64 i_max_offset;  /* largest readdir offset, set with D_COMPLETE */
268 
269 	struct rb_root i_fragtree;
270 	struct mutex i_fragtree_mutex;
271 
272 	struct ceph_inode_xattrs_info i_xattrs;
273 
274 	/* capabilities.  protected _both_ by i_lock and cap->session's
275 	 * s_mutex. */
276 	struct rb_root i_caps;           /* cap list */
277 	struct ceph_cap *i_auth_cap;     /* authoritative cap, if any */
278 	unsigned i_dirty_caps, i_flushing_caps;     /* mask of dirtied fields */
279 	struct list_head i_dirty_item, i_flushing_item;
280 	u64 i_cap_flush_seq;
281 	/* we need to track cap writeback on a per-cap-bit basis, to allow
282 	 * overlapping, pipelined cap flushes to the mds.  we can probably
283 	 * reduce the tid to 8 bits if we're concerned about inode size. */
284 	u16 i_cap_flush_last_tid, i_cap_flush_tid[CEPH_CAP_BITS];
285 	wait_queue_head_t i_cap_wq;      /* threads waiting on a capability */
286 	unsigned long i_hold_caps_min; /* jiffies */
287 	unsigned long i_hold_caps_max; /* jiffies */
288 	struct list_head i_cap_delay_list;  /* for delayed cap release to mds */
289 	int i_cap_exporting_mds;         /* to handle cap migration between */
290 	unsigned i_cap_exporting_mseq;   /*  mds's. */
291 	unsigned i_cap_exporting_issued;
292 	struct ceph_cap_reservation i_cap_migration_resv;
293 	struct list_head i_cap_snaps;   /* snapped state pending flush to mds */
294 	struct ceph_snap_context *i_head_snapc;  /* set if wr_buffer_head > 0 or
295 						    dirty|flushing caps */
296 	unsigned i_snap_caps;           /* cap bits for snapped files */
297 
298 	int i_nr_by_mode[CEPH_FILE_MODE_NUM];  /* open file counts */
299 
300 	u32 i_truncate_seq;        /* last truncate to smaller size */
301 	u64 i_truncate_size;       /*  and the size we last truncated down to */
302 	int i_truncate_pending;    /*  still need to call vmtruncate */
303 
304 	u64 i_max_size;            /* max file size authorized by mds */
305 	u64 i_reported_size; /* (max_)size reported to or requested of mds */
306 	u64 i_wanted_max_size;     /* offset we'd like to write too */
307 	u64 i_requested_max_size;  /* max_size we've requested */
308 
309 	/* held references to caps */
310 	int i_pin_ref;
311 	int i_rd_ref, i_rdcache_ref, i_wr_ref, i_wb_ref;
312 	int i_wrbuffer_ref, i_wrbuffer_ref_head;
313 	u32 i_shared_gen;       /* increment each time we get FILE_SHARED */
314 	u32 i_rdcache_gen;      /* incremented each time we get FILE_CACHE. */
315 	u32 i_rdcache_revoking; /* RDCACHE gen to async invalidate, if any */
316 
317 	struct list_head i_unsafe_writes; /* uncommitted sync writes */
318 	struct list_head i_unsafe_dirops; /* uncommitted mds dir ops */
319 	spinlock_t i_unsafe_lock;
320 
321 	struct ceph_snap_realm *i_snap_realm; /* snap realm (if caps) */
322 	int i_snap_realm_counter; /* snap realm (if caps) */
323 	struct list_head i_snap_realm_item;
324 	struct list_head i_snap_flush_item;
325 
326 	struct work_struct i_wb_work;  /* writeback work */
327 	struct work_struct i_pg_inv_work;  /* page invalidation work */
328 
329 	struct work_struct i_vmtruncate_work;
330 
331 	struct inode vfs_inode; /* at end */
332 };
333 
334 static inline struct ceph_inode_info *ceph_inode(struct inode *inode)
335 {
336 	return container_of(inode, struct ceph_inode_info, vfs_inode);
337 }
338 
339 static inline struct ceph_fs_client *ceph_inode_to_client(struct inode *inode)
340 {
341 	return (struct ceph_fs_client *)inode->i_sb->s_fs_info;
342 }
343 
344 static inline struct ceph_fs_client *ceph_sb_to_client(struct super_block *sb)
345 {
346 	return (struct ceph_fs_client *)sb->s_fs_info;
347 }
348 
349 static inline struct ceph_vino ceph_vino(struct inode *inode)
350 {
351 	return ceph_inode(inode)->i_vino;
352 }
353 
354 /*
355  * ino_t is <64 bits on many architectures, blech.
356  *
357  *               i_ino (kernel inode)   st_ino (userspace)
358  * i386          32                     32
359  * x86_64+ino32  64                     32
360  * x86_64        64                     64
361  */
362 static inline u32 ceph_ino_to_ino32(__u64 vino)
363 {
364 	u32 ino = vino & 0xffffffff;
365 	ino ^= vino >> 32;
366 	if (!ino)
367 		ino = 1;
368 	return ino;
369 }
370 
371 /*
372  * kernel i_ino value
373  */
374 static inline ino_t ceph_vino_to_ino(struct ceph_vino vino)
375 {
376 #if BITS_PER_LONG == 32
377 	return ceph_ino_to_ino32(vino.ino);
378 #else
379 	return (ino_t)vino.ino;
380 #endif
381 }
382 
383 /*
384  * user-visible ino (stat, filldir)
385  */
386 #if BITS_PER_LONG == 32
387 static inline ino_t ceph_translate_ino(struct super_block *sb, ino_t ino)
388 {
389 	return ino;
390 }
391 #else
392 static inline ino_t ceph_translate_ino(struct super_block *sb, ino_t ino)
393 {
394 	if (ceph_test_mount_opt(ceph_sb_to_client(sb), INO32))
395 		ino = ceph_ino_to_ino32(ino);
396 	return ino;
397 }
398 #endif
399 
400 
401 /* for printf-style formatting */
402 #define ceph_vinop(i) ceph_inode(i)->i_vino.ino, ceph_inode(i)->i_vino.snap
403 
404 static inline u64 ceph_ino(struct inode *inode)
405 {
406 	return ceph_inode(inode)->i_vino.ino;
407 }
408 static inline u64 ceph_snap(struct inode *inode)
409 {
410 	return ceph_inode(inode)->i_vino.snap;
411 }
412 
413 static inline int ceph_ino_compare(struct inode *inode, void *data)
414 {
415 	struct ceph_vino *pvino = (struct ceph_vino *)data;
416 	struct ceph_inode_info *ci = ceph_inode(inode);
417 	return ci->i_vino.ino == pvino->ino &&
418 		ci->i_vino.snap == pvino->snap;
419 }
420 
421 static inline struct inode *ceph_find_inode(struct super_block *sb,
422 					    struct ceph_vino vino)
423 {
424 	ino_t t = ceph_vino_to_ino(vino);
425 	return ilookup5(sb, t, ceph_ino_compare, &vino);
426 }
427 
428 
429 /*
430  * Ceph inode.
431  */
432 #define CEPH_I_NODELAY   4  /* do not delay cap release */
433 #define CEPH_I_FLUSH     8  /* do not delay flush of dirty metadata */
434 #define CEPH_I_NOFLUSH  16  /* do not flush dirty caps */
435 
436 static inline void ceph_i_clear(struct inode *inode, unsigned mask)
437 {
438 	struct ceph_inode_info *ci = ceph_inode(inode);
439 
440 	spin_lock(&inode->i_lock);
441 	ci->i_ceph_flags &= ~mask;
442 	spin_unlock(&inode->i_lock);
443 }
444 
445 static inline void ceph_i_set(struct inode *inode, unsigned mask)
446 {
447 	struct ceph_inode_info *ci = ceph_inode(inode);
448 
449 	spin_lock(&inode->i_lock);
450 	ci->i_ceph_flags |= mask;
451 	spin_unlock(&inode->i_lock);
452 }
453 
454 static inline bool ceph_i_test(struct inode *inode, unsigned mask)
455 {
456 	struct ceph_inode_info *ci = ceph_inode(inode);
457 	bool r;
458 
459 	spin_lock(&inode->i_lock);
460 	r = (ci->i_ceph_flags & mask) == mask;
461 	spin_unlock(&inode->i_lock);
462 	return r;
463 }
464 
465 
466 /* find a specific frag @f */
467 extern struct ceph_inode_frag *__ceph_find_frag(struct ceph_inode_info *ci,
468 						u32 f);
469 
470 /*
471  * choose fragment for value @v.  copy frag content to pfrag, if leaf
472  * exists
473  */
474 extern u32 ceph_choose_frag(struct ceph_inode_info *ci, u32 v,
475 			    struct ceph_inode_frag *pfrag,
476 			    int *found);
477 
478 static inline struct ceph_dentry_info *ceph_dentry(struct dentry *dentry)
479 {
480 	return (struct ceph_dentry_info *)dentry->d_fsdata;
481 }
482 
483 static inline loff_t ceph_make_fpos(unsigned frag, unsigned off)
484 {
485 	return ((loff_t)frag << 32) | (loff_t)off;
486 }
487 
488 /*
489  * set/clear directory D_COMPLETE flag
490  */
491 void ceph_dir_set_complete(struct inode *inode);
492 void ceph_dir_clear_complete(struct inode *inode);
493 bool ceph_dir_test_complete(struct inode *inode);
494 
495 /*
496  * caps helpers
497  */
498 static inline bool __ceph_is_any_real_caps(struct ceph_inode_info *ci)
499 {
500 	return !RB_EMPTY_ROOT(&ci->i_caps);
501 }
502 
503 extern int __ceph_caps_issued(struct ceph_inode_info *ci, int *implemented);
504 extern int __ceph_caps_issued_mask(struct ceph_inode_info *ci, int mask, int t);
505 extern int __ceph_caps_issued_other(struct ceph_inode_info *ci,
506 				    struct ceph_cap *cap);
507 
508 static inline int ceph_caps_issued(struct ceph_inode_info *ci)
509 {
510 	int issued;
511 	spin_lock(&ci->vfs_inode.i_lock);
512 	issued = __ceph_caps_issued(ci, NULL);
513 	spin_unlock(&ci->vfs_inode.i_lock);
514 	return issued;
515 }
516 
517 static inline int ceph_caps_issued_mask(struct ceph_inode_info *ci, int mask,
518 					int touch)
519 {
520 	int r;
521 	spin_lock(&ci->vfs_inode.i_lock);
522 	r = __ceph_caps_issued_mask(ci, mask, touch);
523 	spin_unlock(&ci->vfs_inode.i_lock);
524 	return r;
525 }
526 
527 static inline int __ceph_caps_dirty(struct ceph_inode_info *ci)
528 {
529 	return ci->i_dirty_caps | ci->i_flushing_caps;
530 }
531 extern int __ceph_mark_dirty_caps(struct ceph_inode_info *ci, int mask);
532 
533 extern int ceph_caps_revoking(struct ceph_inode_info *ci, int mask);
534 extern int __ceph_caps_used(struct ceph_inode_info *ci);
535 
536 extern int __ceph_caps_file_wanted(struct ceph_inode_info *ci);
537 
538 /*
539  * wanted, by virtue of open file modes AND cap refs (buffered/cached data)
540  */
541 static inline int __ceph_caps_wanted(struct ceph_inode_info *ci)
542 {
543 	int w = __ceph_caps_file_wanted(ci) | __ceph_caps_used(ci);
544 	if (w & CEPH_CAP_FILE_BUFFER)
545 		w |= CEPH_CAP_FILE_EXCL;  /* we want EXCL if dirty data */
546 	return w;
547 }
548 
549 /* what the mds thinks we want */
550 extern int __ceph_caps_mds_wanted(struct ceph_inode_info *ci);
551 
552 extern void ceph_caps_init(struct ceph_mds_client *mdsc);
553 extern void ceph_caps_finalize(struct ceph_mds_client *mdsc);
554 extern void ceph_adjust_min_caps(struct ceph_mds_client *mdsc, int delta);
555 extern int ceph_reserve_caps(struct ceph_mds_client *mdsc,
556 			     struct ceph_cap_reservation *ctx, int need);
557 extern int ceph_unreserve_caps(struct ceph_mds_client *mdsc,
558 			       struct ceph_cap_reservation *ctx);
559 extern void ceph_reservation_status(struct ceph_fs_client *client,
560 				    int *total, int *avail, int *used,
561 				    int *reserved, int *min);
562 
563 
564 
565 /*
566  * we keep buffered readdir results attached to file->private_data
567  */
568 #define CEPH_F_SYNC     1
569 #define CEPH_F_ATEND    2
570 
571 struct ceph_file_info {
572 	short fmode;     /* initialized on open */
573 	short flags;     /* CEPH_F_* */
574 
575 	/* readdir: position within the dir */
576 	u32 frag;
577 	struct ceph_mds_request *last_readdir;
578 
579 	/* readdir: position within a frag */
580 	unsigned offset;       /* offset of last chunk, adjusted for . and .. */
581 	u64 next_offset;       /* offset of next chunk (last_name's + 1) */
582 	char *last_name;       /* last entry in previous chunk */
583 	struct dentry *dentry; /* next dentry (for dcache readdir) */
584 	unsigned long dir_release_count;
585 
586 	/* used for -o dirstat read() on directory thing */
587 	char *dir_info;
588 	int dir_info_len;
589 };
590 
591 
592 
593 /*
594  * A "snap realm" describes a subset of the file hierarchy sharing
595  * the same set of snapshots that apply to it.  The realms themselves
596  * are organized into a hierarchy, such that children inherit (some of)
597  * the snapshots of their parents.
598  *
599  * All inodes within the realm that have capabilities are linked into a
600  * per-realm list.
601  */
602 struct ceph_snap_realm {
603 	u64 ino;
604 	atomic_t nref;
605 	struct rb_node node;
606 
607 	u64 created, seq;
608 	u64 parent_ino;
609 	u64 parent_since;   /* snapid when our current parent became so */
610 
611 	u64 *prior_parent_snaps;      /* snaps inherited from any parents we */
612 	int num_prior_parent_snaps;   /*  had prior to parent_since */
613 	u64 *snaps;                   /* snaps specific to this realm */
614 	int num_snaps;
615 
616 	struct ceph_snap_realm *parent;
617 	struct list_head children;       /* list of child realms */
618 	struct list_head child_item;
619 
620 	struct list_head empty_item;     /* if i have ref==0 */
621 
622 	struct list_head dirty_item;     /* if realm needs new context */
623 
624 	/* the current set of snaps for this realm */
625 	struct ceph_snap_context *cached_context;
626 
627 	struct list_head inodes_with_caps;
628 	spinlock_t inodes_with_caps_lock;
629 };
630 
631 static inline int default_congestion_kb(void)
632 {
633 	int congestion_kb;
634 
635 	/*
636 	 * Copied from NFS
637 	 *
638 	 * congestion size, scale with available memory.
639 	 *
640 	 *  64MB:    8192k
641 	 * 128MB:   11585k
642 	 * 256MB:   16384k
643 	 * 512MB:   23170k
644 	 *   1GB:   32768k
645 	 *   2GB:   46340k
646 	 *   4GB:   65536k
647 	 *   8GB:   92681k
648 	 *  16GB:  131072k
649 	 *
650 	 * This allows larger machines to have larger/more transfers.
651 	 * Limit the default to 256M
652 	 */
653 	congestion_kb = (16*int_sqrt(totalram_pages)) << (PAGE_SHIFT-10);
654 	if (congestion_kb > 256*1024)
655 		congestion_kb = 256*1024;
656 
657 	return congestion_kb;
658 }
659 
660 
661 
662 /* snap.c */
663 struct ceph_snap_realm *ceph_lookup_snap_realm(struct ceph_mds_client *mdsc,
664 					       u64 ino);
665 extern void ceph_get_snap_realm(struct ceph_mds_client *mdsc,
666 				struct ceph_snap_realm *realm);
667 extern void ceph_put_snap_realm(struct ceph_mds_client *mdsc,
668 				struct ceph_snap_realm *realm);
669 extern int ceph_update_snap_trace(struct ceph_mds_client *m,
670 				  void *p, void *e, bool deletion);
671 extern void ceph_handle_snap(struct ceph_mds_client *mdsc,
672 			     struct ceph_mds_session *session,
673 			     struct ceph_msg *msg);
674 extern void ceph_queue_cap_snap(struct ceph_inode_info *ci);
675 extern int __ceph_finish_cap_snap(struct ceph_inode_info *ci,
676 				  struct ceph_cap_snap *capsnap);
677 extern void ceph_cleanup_empty_realms(struct ceph_mds_client *mdsc);
678 
679 /*
680  * a cap_snap is "pending" if it is still awaiting an in-progress
681  * sync write (that may/may not still update size, mtime, etc.).
682  */
683 static inline bool __ceph_have_pending_cap_snap(struct ceph_inode_info *ci)
684 {
685 	return !list_empty(&ci->i_cap_snaps) &&
686 		list_entry(ci->i_cap_snaps.prev, struct ceph_cap_snap,
687 			   ci_item)->writing;
688 }
689 
690 /* inode.c */
691 extern const struct inode_operations ceph_file_iops;
692 
693 extern struct inode *ceph_alloc_inode(struct super_block *sb);
694 extern void ceph_destroy_inode(struct inode *inode);
695 
696 extern struct inode *ceph_get_inode(struct super_block *sb,
697 				    struct ceph_vino vino);
698 extern struct inode *ceph_get_snapdir(struct inode *parent);
699 extern int ceph_fill_file_size(struct inode *inode, int issued,
700 			       u32 truncate_seq, u64 truncate_size, u64 size);
701 extern void ceph_fill_file_time(struct inode *inode, int issued,
702 				u64 time_warp_seq, struct timespec *ctime,
703 				struct timespec *mtime, struct timespec *atime);
704 extern int ceph_fill_trace(struct super_block *sb,
705 			   struct ceph_mds_request *req,
706 			   struct ceph_mds_session *session);
707 extern int ceph_readdir_prepopulate(struct ceph_mds_request *req,
708 				    struct ceph_mds_session *session);
709 
710 extern int ceph_inode_holds_cap(struct inode *inode, int mask);
711 
712 extern int ceph_inode_set_size(struct inode *inode, loff_t size);
713 extern void __ceph_do_pending_vmtruncate(struct inode *inode);
714 extern void ceph_queue_vmtruncate(struct inode *inode);
715 
716 extern void ceph_queue_invalidate(struct inode *inode);
717 extern void ceph_queue_writeback(struct inode *inode);
718 
719 extern int ceph_do_getattr(struct inode *inode, int mask);
720 extern int ceph_permission(struct inode *inode, int mask);
721 extern int ceph_setattr(struct dentry *dentry, struct iattr *attr);
722 extern int ceph_getattr(struct vfsmount *mnt, struct dentry *dentry,
723 			struct kstat *stat);
724 
725 /* xattr.c */
726 extern int ceph_setxattr(struct dentry *, const char *, const void *,
727 			 size_t, int);
728 extern ssize_t ceph_getxattr(struct dentry *, const char *, void *, size_t);
729 extern ssize_t ceph_listxattr(struct dentry *, char *, size_t);
730 extern int ceph_removexattr(struct dentry *, const char *);
731 extern void __ceph_build_xattrs_blob(struct ceph_inode_info *ci);
732 extern void __ceph_destroy_xattrs(struct ceph_inode_info *ci);
733 
734 /* caps.c */
735 extern const char *ceph_cap_string(int c);
736 extern void ceph_handle_caps(struct ceph_mds_session *session,
737 			     struct ceph_msg *msg);
738 extern int ceph_add_cap(struct inode *inode,
739 			struct ceph_mds_session *session, u64 cap_id,
740 			int fmode, unsigned issued, unsigned wanted,
741 			unsigned cap, unsigned seq, u64 realmino, int flags,
742 			struct ceph_cap_reservation *caps_reservation);
743 extern void __ceph_remove_cap(struct ceph_cap *cap);
744 static inline void ceph_remove_cap(struct ceph_cap *cap)
745 {
746 	struct inode *inode = &cap->ci->vfs_inode;
747 	spin_lock(&inode->i_lock);
748 	__ceph_remove_cap(cap);
749 	spin_unlock(&inode->i_lock);
750 }
751 extern void ceph_put_cap(struct ceph_mds_client *mdsc,
752 			 struct ceph_cap *cap);
753 
754 extern void ceph_queue_caps_release(struct inode *inode);
755 extern int ceph_write_inode(struct inode *inode, struct writeback_control *wbc);
756 extern int ceph_fsync(struct file *file, loff_t start, loff_t end,
757 		      int datasync);
758 extern void ceph_kick_flushing_caps(struct ceph_mds_client *mdsc,
759 				    struct ceph_mds_session *session);
760 extern struct ceph_cap *ceph_get_cap_for_mds(struct ceph_inode_info *ci,
761 					     int mds);
762 extern int ceph_get_cap_mds(struct inode *inode);
763 extern void ceph_get_cap_refs(struct ceph_inode_info *ci, int caps);
764 extern void ceph_put_cap_refs(struct ceph_inode_info *ci, int had);
765 extern void ceph_put_wrbuffer_cap_refs(struct ceph_inode_info *ci, int nr,
766 				       struct ceph_snap_context *snapc);
767 extern void __ceph_flush_snaps(struct ceph_inode_info *ci,
768 			       struct ceph_mds_session **psession,
769 			       int again);
770 extern void ceph_check_caps(struct ceph_inode_info *ci, int flags,
771 			    struct ceph_mds_session *session);
772 extern void ceph_check_delayed_caps(struct ceph_mds_client *mdsc);
773 extern void ceph_flush_dirty_caps(struct ceph_mds_client *mdsc);
774 
775 extern int ceph_encode_inode_release(void **p, struct inode *inode,
776 				     int mds, int drop, int unless, int force);
777 extern int ceph_encode_dentry_release(void **p, struct dentry *dn,
778 				      int mds, int drop, int unless);
779 
780 extern int ceph_get_caps(struct ceph_inode_info *ci, int need, int want,
781 			 int *got, loff_t endoff);
782 
783 /* for counting open files by mode */
784 static inline void __ceph_get_fmode(struct ceph_inode_info *ci, int mode)
785 {
786 	ci->i_nr_by_mode[mode]++;
787 }
788 extern void ceph_put_fmode(struct ceph_inode_info *ci, int mode);
789 
790 /* addr.c */
791 extern const struct address_space_operations ceph_aops;
792 extern int ceph_mmap(struct file *file, struct vm_area_struct *vma);
793 
794 /* file.c */
795 extern const struct file_operations ceph_file_fops;
796 extern const struct address_space_operations ceph_aops;
797 extern int ceph_copy_to_page_vector(struct page **pages,
798 				    const char *data,
799 				    loff_t off, size_t len);
800 extern int ceph_copy_from_page_vector(struct page **pages,
801 				    char *data,
802 				    loff_t off, size_t len);
803 extern struct page **ceph_alloc_page_vector(int num_pages, gfp_t flags);
804 extern int ceph_open(struct inode *inode, struct file *file);
805 extern struct dentry *ceph_lookup_open(struct inode *dir, struct dentry *dentry,
806 				       struct nameidata *nd, int mode,
807 				       int locked_dir);
808 extern int ceph_release(struct inode *inode, struct file *filp);
809 
810 /* dir.c */
811 extern const struct file_operations ceph_dir_fops;
812 extern const struct inode_operations ceph_dir_iops;
813 extern const struct dentry_operations ceph_dentry_ops, ceph_snap_dentry_ops,
814 	ceph_snapdir_dentry_ops;
815 
816 extern int ceph_handle_notrace_create(struct inode *dir, struct dentry *dentry);
817 extern int ceph_handle_snapdir(struct ceph_mds_request *req,
818 			       struct dentry *dentry, int err);
819 extern struct dentry *ceph_finish_lookup(struct ceph_mds_request *req,
820 					 struct dentry *dentry, int err);
821 
822 extern void ceph_dentry_lru_add(struct dentry *dn);
823 extern void ceph_dentry_lru_touch(struct dentry *dn);
824 extern void ceph_dentry_lru_del(struct dentry *dn);
825 extern void ceph_invalidate_dentry_lease(struct dentry *dentry);
826 extern unsigned ceph_dentry_hash(struct inode *dir, struct dentry *dn);
827 extern struct inode *ceph_get_dentry_parent_inode(struct dentry *dentry);
828 
829 /*
830  * our d_ops vary depending on whether the inode is live,
831  * snapshotted (read-only), or a virtual ".snap" directory.
832  */
833 int ceph_init_dentry(struct dentry *dentry);
834 
835 
836 /* ioctl.c */
837 extern long ceph_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
838 
839 /* export.c */
840 extern const struct export_operations ceph_export_ops;
841 
842 /* locks.c */
843 extern int ceph_lock(struct file *file, int cmd, struct file_lock *fl);
844 extern int ceph_flock(struct file *file, int cmd, struct file_lock *fl);
845 extern void ceph_count_locks(struct inode *inode, int *p_num, int *f_num);
846 extern int ceph_encode_locks(struct inode *i, struct ceph_pagelist *p,
847 			     int p_locks, int f_locks);
848 extern int lock_to_ceph_filelock(struct file_lock *fl, struct ceph_filelock *c);
849 
850 /* debugfs.c */
851 extern int ceph_fs_debugfs_init(struct ceph_fs_client *client);
852 extern void ceph_fs_debugfs_cleanup(struct ceph_fs_client *client);
853 
854 #endif /* _FS_CEPH_SUPER_H */
855