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[J-linux.git] / include / linux / ceph / osd_client.h
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _FS_CEPH_OSD_CLIENT_H
3 #define _FS_CEPH_OSD_CLIENT_H
4
5 #include <linux/bitrev.h>
6 #include <linux/completion.h>
7 #include <linux/kref.h>
8 #include <linux/mempool.h>
9 #include <linux/rbtree.h>
10 #include <linux/refcount.h>
11 #include <linux/ktime.h>
12
13 #include <linux/ceph/types.h>
14 #include <linux/ceph/osdmap.h>
15 #include <linux/ceph/messenger.h>
16 #include <linux/ceph/msgpool.h>
17 #include <linux/ceph/auth.h>
18 #include <linux/ceph/pagelist.h>
19
20 struct ceph_msg;
21 struct ceph_snap_context;
22 struct ceph_osd_request;
23 struct ceph_osd_client;
24
25 /*
26  * completion callback for async writepages
27  */
28 typedef void (*ceph_osdc_callback_t)(struct ceph_osd_request *);
29
30 #define CEPH_HOMELESS_OSD       -1
31
32 /*
33  * A single extent in a SPARSE_READ reply.
34  *
35  * Note that these come from the OSD as little-endian values. On BE arches,
36  * we convert them in-place after receipt.
37  */
38 struct ceph_sparse_extent {
39         u64     off;
40         u64     len;
41 } __packed;
42
43 /* Sparse read state machine state values */
44 enum ceph_sparse_read_state {
45         CEPH_SPARSE_READ_HDR    = 0,
46         CEPH_SPARSE_READ_EXTENTS,
47         CEPH_SPARSE_READ_DATA_LEN,
48         CEPH_SPARSE_READ_DATA,
49 };
50
51 /*
52  * A SPARSE_READ reply is a 32-bit count of extents, followed by an array of
53  * 64-bit offset/length pairs, and then all of the actual file data
54  * concatenated after it (sans holes).
55  *
56  * Unfortunately, we don't know how long the extent array is until we've
57  * started reading the data section of the reply. The caller should send down
58  * a destination buffer for the array, but we'll alloc one if it's too small
59  * or if the caller doesn't.
60  */
61 struct ceph_sparse_read {
62         enum ceph_sparse_read_state     sr_state;    /* state machine state */
63         u64                             sr_req_off;  /* orig request offset */
64         u64                             sr_req_len;  /* orig request length */
65         u64                             sr_pos;      /* current pos in buffer */
66         int                             sr_index;    /* current extent index */
67         __le32                          sr_datalen;  /* length of actual data */
68         u32                             sr_count;    /* extent count in reply */
69         int                             sr_ext_len;  /* length of extent array */
70         struct ceph_sparse_extent       *sr_extent;  /* extent array */
71 };
72
73 /*
74  * A given osd we're communicating with.
75  *
76  * Note that the o_requests tree can be searched while holding the "lock" mutex
77  * or the "o_requests_lock" spinlock. Insertion or removal requires both!
78  */
79 struct ceph_osd {
80         refcount_t o_ref;
81         int o_sparse_op_idx;
82         struct ceph_osd_client *o_osdc;
83         int o_osd;
84         int o_incarnation;
85         struct rb_node o_node;
86         struct ceph_connection o_con;
87         spinlock_t o_requests_lock;
88         struct rb_root o_requests;
89         struct rb_root o_linger_requests;
90         struct rb_root o_backoff_mappings;
91         struct rb_root o_backoffs_by_id;
92         struct list_head o_osd_lru;
93         struct ceph_auth_handshake o_auth;
94         unsigned long lru_ttl;
95         struct list_head o_keepalive_item;
96         struct mutex lock;
97         struct ceph_sparse_read o_sparse_read;
98 };
99
100 #define CEPH_OSD_SLAB_OPS       2
101 #define CEPH_OSD_MAX_OPS        16
102
103 enum ceph_osd_data_type {
104         CEPH_OSD_DATA_TYPE_NONE = 0,
105         CEPH_OSD_DATA_TYPE_PAGES,
106         CEPH_OSD_DATA_TYPE_PAGELIST,
107 #ifdef CONFIG_BLOCK
108         CEPH_OSD_DATA_TYPE_BIO,
109 #endif /* CONFIG_BLOCK */
110         CEPH_OSD_DATA_TYPE_BVECS,
111         CEPH_OSD_DATA_TYPE_ITER,
112 };
113
114 struct ceph_osd_data {
115         enum ceph_osd_data_type type;
116         union {
117                 struct {
118                         struct page     **pages;
119                         u64             length;
120                         u32             alignment;
121                         bool            pages_from_pool;
122                         bool            own_pages;
123                 };
124                 struct ceph_pagelist    *pagelist;
125 #ifdef CONFIG_BLOCK
126                 struct {
127                         struct ceph_bio_iter    bio_pos;
128                         u32                     bio_length;
129                 };
130 #endif /* CONFIG_BLOCK */
131                 struct {
132                         struct ceph_bvec_iter   bvec_pos;
133                         u32                     num_bvecs;
134                 };
135                 struct iov_iter         iter;
136         };
137 };
138
139 struct ceph_osd_req_op {
140         u16 op;           /* CEPH_OSD_OP_* */
141         u32 flags;        /* CEPH_OSD_OP_FLAG_* */
142         u32 indata_len;   /* request */
143         u32 outdata_len;  /* reply */
144         s32 rval;
145
146         union {
147                 struct ceph_osd_data raw_data_in;
148                 struct {
149                         u64 offset, length;
150                         u64 truncate_size;
151                         u32 truncate_seq;
152                         int sparse_ext_cnt;
153                         struct ceph_sparse_extent *sparse_ext;
154                         struct ceph_osd_data osd_data;
155                 } extent;
156                 struct {
157                         u32 name_len;
158                         u32 value_len;
159                         __u8 cmp_op;       /* CEPH_OSD_CMPXATTR_OP_* */
160                         __u8 cmp_mode;     /* CEPH_OSD_CMPXATTR_MODE_* */
161                         struct ceph_osd_data osd_data;
162                 } xattr;
163                 struct {
164                         const char *class_name;
165                         const char *method_name;
166                         struct ceph_osd_data request_info;
167                         struct ceph_osd_data request_data;
168                         struct ceph_osd_data response_data;
169                         __u8 class_len;
170                         __u8 method_len;
171                         u32 indata_len;
172                 } cls;
173                 struct {
174                         u64 cookie;
175                         __u8 op;           /* CEPH_OSD_WATCH_OP_ */
176                         u32 gen;
177                 } watch;
178                 struct {
179                         struct ceph_osd_data request_data;
180                 } notify_ack;
181                 struct {
182                         u64 cookie;
183                         struct ceph_osd_data request_data;
184                         struct ceph_osd_data response_data;
185                 } notify;
186                 struct {
187                         struct ceph_osd_data response_data;
188                 } list_watchers;
189                 struct {
190                         u64 expected_object_size;
191                         u64 expected_write_size;
192                         u32 flags;  /* CEPH_OSD_OP_ALLOC_HINT_FLAG_* */
193                 } alloc_hint;
194                 struct {
195                         u64 snapid;
196                         u64 src_version;
197                         u8 flags;
198                         u32 src_fadvise_flags;
199                         struct ceph_osd_data osd_data;
200                 } copy_from;
201                 struct {
202                         u64 ver;
203                 } assert_ver;
204         };
205 };
206
207 struct ceph_osd_request_target {
208         struct ceph_object_id base_oid;
209         struct ceph_object_locator base_oloc;
210         struct ceph_object_id target_oid;
211         struct ceph_object_locator target_oloc;
212
213         struct ceph_pg pgid;               /* last raw pg we mapped to */
214         struct ceph_spg spgid;             /* last actual spg we mapped to */
215         u32 pg_num;
216         u32 pg_num_mask;
217         struct ceph_osds acting;
218         struct ceph_osds up;
219         int size;
220         int min_size;
221         bool sort_bitwise;
222         bool recovery_deletes;
223
224         unsigned int flags;                /* CEPH_OSD_FLAG_* */
225         bool used_replica;
226         bool paused;
227
228         u32 epoch;
229         u32 last_force_resend;
230
231         int osd;
232 };
233
234 /* an in-flight request */
235 struct ceph_osd_request {
236         u64             r_tid;              /* unique for this client */
237         struct rb_node  r_node;
238         struct rb_node  r_mc_node;          /* map check */
239         struct work_struct r_complete_work;
240         struct ceph_osd *r_osd;
241
242         struct ceph_osd_request_target r_t;
243 #define r_base_oid      r_t.base_oid
244 #define r_base_oloc     r_t.base_oloc
245 #define r_flags         r_t.flags
246
247         struct ceph_msg  *r_request, *r_reply;
248         u32               r_sent;      /* >0 if r_request is sending/sent */
249
250         /* request osd ops array  */
251         unsigned int            r_num_ops;
252
253         int               r_result;
254
255         struct ceph_osd_client *r_osdc;
256         struct kref       r_kref;
257         bool              r_mempool;
258         bool              r_linger;           /* don't resend on failure */
259         struct completion r_completion;       /* private to osd_client.c */
260         ceph_osdc_callback_t r_callback;
261
262         struct inode *r_inode;                /* for use by callbacks */
263         struct list_head r_private_item;      /* ditto */
264         void *r_priv;                         /* ditto */
265
266         /* set by submitter */
267         u64 r_snapid;                         /* for reads, CEPH_NOSNAP o/w */
268         struct ceph_snap_context *r_snapc;    /* for writes */
269         struct timespec64 r_mtime;            /* ditto */
270         u64 r_data_offset;                    /* ditto */
271
272         /* internal */
273         u64 r_version;                        /* data version sent in reply */
274         unsigned long r_stamp;                /* jiffies, send or check time */
275         unsigned long r_start_stamp;          /* jiffies */
276         ktime_t r_start_latency;              /* ktime_t */
277         ktime_t r_end_latency;                /* ktime_t */
278         int r_attempts;
279         u32 r_map_dne_bound;
280
281         struct ceph_osd_req_op r_ops[];
282 };
283
284 struct ceph_request_redirect {
285         struct ceph_object_locator oloc;
286 };
287
288 /*
289  * osd request identifier
290  *
291  * caller name + incarnation# + tid to unique identify this request
292  */
293 struct ceph_osd_reqid {
294         struct ceph_entity_name name;
295         __le64 tid;
296         __le32 inc;
297 } __packed;
298
299 struct ceph_blkin_trace_info {
300         __le64 trace_id;
301         __le64 span_id;
302         __le64 parent_span_id;
303 } __packed;
304
305 typedef void (*rados_watchcb2_t)(void *arg, u64 notify_id, u64 cookie,
306                                  u64 notifier_id, void *data, size_t data_len);
307 typedef void (*rados_watcherrcb_t)(void *arg, u64 cookie, int err);
308
309 struct ceph_osd_linger_request {
310         struct ceph_osd_client *osdc;
311         u64 linger_id;
312         bool committed;
313         bool is_watch;                  /* watch or notify */
314
315         struct ceph_osd *osd;
316         struct ceph_osd_request *reg_req;
317         struct ceph_osd_request *ping_req;
318         unsigned long ping_sent;
319         unsigned long watch_valid_thru;
320         struct list_head pending_lworks;
321
322         struct ceph_osd_request_target t;
323         u32 map_dne_bound;
324
325         struct timespec64 mtime;
326
327         struct kref kref;
328         struct mutex lock;
329         struct rb_node node;            /* osd */
330         struct rb_node osdc_node;       /* osdc */
331         struct rb_node mc_node;         /* map check */
332         struct list_head scan_item;
333
334         struct completion reg_commit_wait;
335         struct completion notify_finish_wait;
336         int reg_commit_error;
337         int notify_finish_error;
338         int last_error;
339
340         u32 register_gen;
341         u64 notify_id;
342
343         rados_watchcb2_t wcb;
344         rados_watcherrcb_t errcb;
345         void *data;
346
347         struct ceph_pagelist *request_pl;
348         struct page **notify_id_pages;
349
350         struct page ***preply_pages;
351         size_t *preply_len;
352 };
353
354 struct ceph_watch_item {
355         struct ceph_entity_name name;
356         u64 cookie;
357         struct ceph_entity_addr addr;
358 };
359
360 struct ceph_spg_mapping {
361         struct rb_node node;
362         struct ceph_spg spgid;
363
364         struct rb_root backoffs;
365 };
366
367 struct ceph_hobject_id {
368         void *key;
369         size_t key_len;
370         void *oid;
371         size_t oid_len;
372         u64 snapid;
373         u32 hash;
374         u8 is_max;
375         void *nspace;
376         size_t nspace_len;
377         s64 pool;
378
379         /* cache */
380         u32 hash_reverse_bits;
381 };
382
383 static inline void ceph_hoid_build_hash_cache(struct ceph_hobject_id *hoid)
384 {
385         hoid->hash_reverse_bits = bitrev32(hoid->hash);
386 }
387
388 /*
389  * PG-wide backoff: [begin, end)
390  * per-object backoff: begin == end
391  */
392 struct ceph_osd_backoff {
393         struct rb_node spg_node;
394         struct rb_node id_node;
395
396         struct ceph_spg spgid;
397         u64 id;
398         struct ceph_hobject_id *begin;
399         struct ceph_hobject_id *end;
400 };
401
402 #define CEPH_LINGER_ID_START    0xffff000000000000ULL
403
404 struct ceph_osd_client {
405         struct ceph_client     *client;
406
407         struct ceph_osdmap     *osdmap;       /* current map */
408         struct rw_semaphore    lock;
409
410         struct rb_root         osds;          /* osds */
411         struct list_head       osd_lru;       /* idle osds */
412         spinlock_t             osd_lru_lock;
413         u32                    epoch_barrier;
414         struct ceph_osd        homeless_osd;
415         atomic64_t             last_tid;      /* tid of last request */
416         u64                    last_linger_id;
417         struct rb_root         linger_requests; /* lingering requests */
418         struct rb_root         map_checks;
419         struct rb_root         linger_map_checks;
420         atomic_t               num_requests;
421         atomic_t               num_homeless;
422         int                    abort_err;
423         struct delayed_work    timeout_work;
424         struct delayed_work    osds_timeout_work;
425 #ifdef CONFIG_DEBUG_FS
426         struct dentry          *debugfs_file;
427 #endif
428
429         mempool_t              *req_mempool;
430
431         struct ceph_msgpool     msgpool_op;
432         struct ceph_msgpool     msgpool_op_reply;
433
434         struct workqueue_struct *notify_wq;
435         struct workqueue_struct *completion_wq;
436 };
437
438 static inline bool ceph_osdmap_flag(struct ceph_osd_client *osdc, int flag)
439 {
440         return osdc->osdmap->flags & flag;
441 }
442
443 extern int ceph_osdc_setup(void);
444 extern void ceph_osdc_cleanup(void);
445
446 extern int ceph_osdc_init(struct ceph_osd_client *osdc,
447                           struct ceph_client *client);
448 extern void ceph_osdc_stop(struct ceph_osd_client *osdc);
449 extern void ceph_osdc_reopen_osds(struct ceph_osd_client *osdc);
450
451 extern void ceph_osdc_handle_reply(struct ceph_osd_client *osdc,
452                                    struct ceph_msg *msg);
453 extern void ceph_osdc_handle_map(struct ceph_osd_client *osdc,
454                                  struct ceph_msg *msg);
455 void ceph_osdc_update_epoch_barrier(struct ceph_osd_client *osdc, u32 eb);
456 void ceph_osdc_abort_requests(struct ceph_osd_client *osdc, int err);
457 void ceph_osdc_clear_abort_err(struct ceph_osd_client *osdc);
458
459 #define osd_req_op_data(oreq, whch, typ, fld)                           \
460 ({                                                                      \
461         struct ceph_osd_request *__oreq = (oreq);                       \
462         unsigned int __whch = (whch);                                   \
463         BUG_ON(__whch >= __oreq->r_num_ops);                            \
464         &__oreq->r_ops[__whch].typ.fld;                                 \
465 })
466
467 struct ceph_osd_req_op *osd_req_op_init(struct ceph_osd_request *osd_req,
468                             unsigned int which, u16 opcode, u32 flags);
469
470 extern void osd_req_op_raw_data_in_pages(struct ceph_osd_request *,
471                                         unsigned int which,
472                                         struct page **pages, u64 length,
473                                         u32 alignment, bool pages_from_pool,
474                                         bool own_pages);
475
476 extern void osd_req_op_extent_init(struct ceph_osd_request *osd_req,
477                                         unsigned int which, u16 opcode,
478                                         u64 offset, u64 length,
479                                         u64 truncate_size, u32 truncate_seq);
480 extern void osd_req_op_extent_update(struct ceph_osd_request *osd_req,
481                                         unsigned int which, u64 length);
482 extern void osd_req_op_extent_dup_last(struct ceph_osd_request *osd_req,
483                                        unsigned int which, u64 offset_inc);
484
485 extern struct ceph_osd_data *osd_req_op_extent_osd_data(
486                                         struct ceph_osd_request *osd_req,
487                                         unsigned int which);
488
489 extern void osd_req_op_extent_osd_data_pages(struct ceph_osd_request *,
490                                         unsigned int which,
491                                         struct page **pages, u64 length,
492                                         u32 alignment, bool pages_from_pool,
493                                         bool own_pages);
494 extern void osd_req_op_extent_osd_data_pagelist(struct ceph_osd_request *,
495                                         unsigned int which,
496                                         struct ceph_pagelist *pagelist);
497 #ifdef CONFIG_BLOCK
498 void osd_req_op_extent_osd_data_bio(struct ceph_osd_request *osd_req,
499                                     unsigned int which,
500                                     struct ceph_bio_iter *bio_pos,
501                                     u32 bio_length);
502 #endif /* CONFIG_BLOCK */
503 void osd_req_op_extent_osd_data_bvecs(struct ceph_osd_request *osd_req,
504                                       unsigned int which,
505                                       struct bio_vec *bvecs, u32 num_bvecs,
506                                       u32 bytes);
507 void osd_req_op_extent_osd_data_bvec_pos(struct ceph_osd_request *osd_req,
508                                          unsigned int which,
509                                          struct ceph_bvec_iter *bvec_pos);
510 void osd_req_op_extent_osd_iter(struct ceph_osd_request *osd_req,
511                                 unsigned int which, struct iov_iter *iter);
512
513 extern void osd_req_op_cls_request_data_pagelist(struct ceph_osd_request *,
514                                         unsigned int which,
515                                         struct ceph_pagelist *pagelist);
516 extern void osd_req_op_cls_request_data_pages(struct ceph_osd_request *,
517                                         unsigned int which,
518                                         struct page **pages, u64 length,
519                                         u32 alignment, bool pages_from_pool,
520                                         bool own_pages);
521 void osd_req_op_cls_request_data_bvecs(struct ceph_osd_request *osd_req,
522                                        unsigned int which,
523                                        struct bio_vec *bvecs, u32 num_bvecs,
524                                        u32 bytes);
525 extern void osd_req_op_cls_response_data_pages(struct ceph_osd_request *,
526                                         unsigned int which,
527                                         struct page **pages, u64 length,
528                                         u32 alignment, bool pages_from_pool,
529                                         bool own_pages);
530 int osd_req_op_cls_init(struct ceph_osd_request *osd_req, unsigned int which,
531                         const char *class, const char *method);
532 extern int osd_req_op_xattr_init(struct ceph_osd_request *osd_req, unsigned int which,
533                                  u16 opcode, const char *name, const void *value,
534                                  size_t size, u8 cmp_op, u8 cmp_mode);
535 extern void osd_req_op_alloc_hint_init(struct ceph_osd_request *osd_req,
536                                        unsigned int which,
537                                        u64 expected_object_size,
538                                        u64 expected_write_size,
539                                        u32 flags);
540 extern int osd_req_op_copy_from_init(struct ceph_osd_request *req,
541                                      u64 src_snapid, u64 src_version,
542                                      struct ceph_object_id *src_oid,
543                                      struct ceph_object_locator *src_oloc,
544                                      u32 src_fadvise_flags,
545                                      u32 dst_fadvise_flags,
546                                      u32 truncate_seq, u64 truncate_size,
547                                      u8 copy_from_flags);
548
549 extern struct ceph_osd_request *ceph_osdc_alloc_request(struct ceph_osd_client *osdc,
550                                                struct ceph_snap_context *snapc,
551                                                unsigned int num_ops,
552                                                bool use_mempool,
553                                                gfp_t gfp_flags);
554 int ceph_osdc_alloc_messages(struct ceph_osd_request *req, gfp_t gfp);
555
556 extern struct ceph_osd_request *ceph_osdc_new_request(struct ceph_osd_client *,
557                                       struct ceph_file_layout *layout,
558                                       struct ceph_vino vino,
559                                       u64 offset, u64 *len,
560                                       unsigned int which, int num_ops,
561                                       int opcode, int flags,
562                                       struct ceph_snap_context *snapc,
563                                       u32 truncate_seq, u64 truncate_size,
564                                       bool use_mempool);
565
566 int __ceph_alloc_sparse_ext_map(struct ceph_osd_req_op *op, int cnt);
567
568 /*
569  * How big an extent array should we preallocate for a sparse read? This is
570  * just a starting value.  If we get more than this back from the OSD, the
571  * receiver will reallocate.
572  */
573 #define CEPH_SPARSE_EXT_ARRAY_INITIAL  16
574
575 static inline int ceph_alloc_sparse_ext_map(struct ceph_osd_req_op *op)
576 {
577         return __ceph_alloc_sparse_ext_map(op, CEPH_SPARSE_EXT_ARRAY_INITIAL);
578 }
579
580 extern void ceph_osdc_get_request(struct ceph_osd_request *req);
581 extern void ceph_osdc_put_request(struct ceph_osd_request *req);
582
583 void ceph_osdc_start_request(struct ceph_osd_client *osdc,
584                              struct ceph_osd_request *req);
585 extern void ceph_osdc_cancel_request(struct ceph_osd_request *req);
586 extern int ceph_osdc_wait_request(struct ceph_osd_client *osdc,
587                                   struct ceph_osd_request *req);
588 extern void ceph_osdc_sync(struct ceph_osd_client *osdc);
589
590 extern void ceph_osdc_flush_notifies(struct ceph_osd_client *osdc);
591 void ceph_osdc_maybe_request_map(struct ceph_osd_client *osdc);
592
593 int ceph_osdc_call(struct ceph_osd_client *osdc,
594                    struct ceph_object_id *oid,
595                    struct ceph_object_locator *oloc,
596                    const char *class, const char *method,
597                    unsigned int flags,
598                    struct page *req_page, size_t req_len,
599                    struct page **resp_pages, size_t *resp_len);
600
601 /* watch/notify */
602 struct ceph_osd_linger_request *
603 ceph_osdc_watch(struct ceph_osd_client *osdc,
604                 struct ceph_object_id *oid,
605                 struct ceph_object_locator *oloc,
606                 rados_watchcb2_t wcb,
607                 rados_watcherrcb_t errcb,
608                 void *data);
609 int ceph_osdc_unwatch(struct ceph_osd_client *osdc,
610                       struct ceph_osd_linger_request *lreq);
611
612 int ceph_osdc_notify_ack(struct ceph_osd_client *osdc,
613                          struct ceph_object_id *oid,
614                          struct ceph_object_locator *oloc,
615                          u64 notify_id,
616                          u64 cookie,
617                          void *payload,
618                          u32 payload_len);
619 int ceph_osdc_notify(struct ceph_osd_client *osdc,
620                      struct ceph_object_id *oid,
621                      struct ceph_object_locator *oloc,
622                      void *payload,
623                      u32 payload_len,
624                      u32 timeout,
625                      struct page ***preply_pages,
626                      size_t *preply_len);
627 int ceph_osdc_watch_check(struct ceph_osd_client *osdc,
628                           struct ceph_osd_linger_request *lreq);
629 int ceph_osdc_list_watchers(struct ceph_osd_client *osdc,
630                             struct ceph_object_id *oid,
631                             struct ceph_object_locator *oloc,
632                             struct ceph_watch_item **watchers,
633                             u32 *num_watchers);
634
635 /* Find offset into the buffer of the end of the extent map */
636 static inline u64 ceph_sparse_ext_map_end(struct ceph_osd_req_op *op)
637 {
638         struct ceph_sparse_extent *ext;
639
640         /* No extents? No data */
641         if (op->extent.sparse_ext_cnt == 0)
642                 return 0;
643
644         ext = &op->extent.sparse_ext[op->extent.sparse_ext_cnt - 1];
645
646         return ext->off + ext->len - op->extent.offset;
647 }
648
649 #endif
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