1 #include <linux/ceph/ceph_debug.h>
3 #include <linux/backing-dev.h>
6 #include <linux/pagemap.h>
7 #include <linux/writeback.h> /* generic_writepages */
8 #include <linux/slab.h>
9 #include <linux/pagevec.h>
10 #include <linux/task_io_accounting_ops.h>
13 #include "mds_client.h"
15 #include <linux/ceph/osd_client.h>
18 * Ceph address space ops.
20 * There are a few funny things going on here.
22 * The page->private field is used to reference a struct
23 * ceph_snap_context for _every_ dirty page. This indicates which
24 * snapshot the page was logically dirtied in, and thus which snap
25 * context needs to be associated with the osd write during writeback.
27 * Similarly, struct ceph_inode_info maintains a set of counters to
28 * count dirty pages on the inode. In the absence of snapshots,
29 * i_wrbuffer_ref == i_wrbuffer_ref_head == the dirty page count.
31 * When a snapshot is taken (that is, when the client receives
32 * notification that a snapshot was taken), each inode with caps and
33 * with dirty pages (dirty pages implies there is a cap) gets a new
34 * ceph_cap_snap in the i_cap_snaps list (which is sorted in ascending
35 * order, new snaps go to the tail). The i_wrbuffer_ref_head count is
36 * moved to capsnap->dirty. (Unless a sync write is currently in
37 * progress. In that case, the capsnap is said to be "pending", new
38 * writes cannot start, and the capsnap isn't "finalized" until the
39 * write completes (or fails) and a final size/mtime for the inode for
40 * that snap can be settled upon.) i_wrbuffer_ref_head is reset to 0.
42 * On writeback, we must submit writes to the osd IN SNAP ORDER. So,
43 * we look for the first capsnap in i_cap_snaps and write out pages in
44 * that snap context _only_. Then we move on to the next capsnap,
45 * eventually reaching the "live" or "head" context (i.e., pages that
46 * are not yet snapped) and are writing the most recently dirtied
49 * Invalidate and so forth must take care to ensure the dirty page
50 * accounting is preserved.
53 #define CONGESTION_ON_THRESH(congestion_kb) (congestion_kb >> (PAGE_SHIFT-10))
54 #define CONGESTION_OFF_THRESH(congestion_kb) \
55 (CONGESTION_ON_THRESH(congestion_kb) - \
56 (CONGESTION_ON_THRESH(congestion_kb) >> 2))
58 static inline struct ceph_snap_context
*page_snap_context(struct page
*page
)
60 if (PagePrivate(page
))
61 return (void *)page
->private;
66 * Dirty a page. Optimistically adjust accounting, on the assumption
67 * that we won't race with invalidate. If we do, readjust.
69 static int ceph_set_page_dirty(struct page
*page
)
71 struct address_space
*mapping
= page
->mapping
;
73 struct ceph_inode_info
*ci
;
74 struct ceph_snap_context
*snapc
;
77 if (unlikely(!mapping
))
78 return !TestSetPageDirty(page
);
80 if (PageDirty(page
)) {
81 dout("%p set_page_dirty %p idx %lu -- already dirty\n",
82 mapping
->host
, page
, page
->index
);
83 BUG_ON(!PagePrivate(page
));
87 inode
= mapping
->host
;
88 ci
= ceph_inode(inode
);
91 * Note that we're grabbing a snapc ref here without holding
94 snapc
= ceph_get_snap_context(ci
->i_snap_realm
->cached_context
);
97 spin_lock(&ci
->i_ceph_lock
);
98 if (ci
->i_head_snapc
== NULL
)
99 ci
->i_head_snapc
= ceph_get_snap_context(snapc
);
100 ++ci
->i_wrbuffer_ref_head
;
101 if (ci
->i_wrbuffer_ref
== 0)
103 ++ci
->i_wrbuffer_ref
;
104 dout("%p set_page_dirty %p idx %lu head %d/%d -> %d/%d "
105 "snapc %p seq %lld (%d snaps)\n",
106 mapping
->host
, page
, page
->index
,
107 ci
->i_wrbuffer_ref
-1, ci
->i_wrbuffer_ref_head
-1,
108 ci
->i_wrbuffer_ref
, ci
->i_wrbuffer_ref_head
,
109 snapc
, snapc
->seq
, snapc
->num_snaps
);
110 spin_unlock(&ci
->i_ceph_lock
);
113 * Reference snap context in page->private. Also set
114 * PagePrivate so that we get invalidatepage callback.
116 BUG_ON(PagePrivate(page
));
117 page
->private = (unsigned long)snapc
;
118 SetPagePrivate(page
);
120 ret
= __set_page_dirty_nobuffers(page
);
121 WARN_ON(!PageLocked(page
));
122 WARN_ON(!page
->mapping
);
128 * If we are truncating the full page (i.e. offset == 0), adjust the
129 * dirty page counters appropriately. Only called if there is private
132 static void ceph_invalidatepage(struct page
*page
, unsigned int offset
,
136 struct ceph_inode_info
*ci
;
137 struct ceph_snap_context
*snapc
= page_snap_context(page
);
139 inode
= page
->mapping
->host
;
140 ci
= ceph_inode(inode
);
142 if (offset
!= 0 || length
!= PAGE_CACHE_SIZE
) {
143 dout("%p invalidatepage %p idx %lu partial dirty page %u~%u\n",
144 inode
, page
, page
->index
, offset
, length
);
148 ceph_invalidate_fscache_page(inode
, page
);
150 if (!PagePrivate(page
))
154 * We can get non-dirty pages here due to races between
155 * set_page_dirty and truncate_complete_page; just spit out a
156 * warning, in case we end up with accounting problems later.
158 if (!PageDirty(page
))
159 pr_err("%p invalidatepage %p page not dirty\n", inode
, page
);
161 ClearPageChecked(page
);
163 dout("%p invalidatepage %p idx %lu full dirty page\n",
164 inode
, page
, page
->index
);
166 ceph_put_wrbuffer_cap_refs(ci
, 1, snapc
);
167 ceph_put_snap_context(snapc
);
169 ClearPagePrivate(page
);
172 static int ceph_releasepage(struct page
*page
, gfp_t g
)
174 struct inode
*inode
= page
->mapping
? page
->mapping
->host
: NULL
;
175 dout("%p releasepage %p idx %lu\n", inode
, page
, page
->index
);
176 WARN_ON(PageDirty(page
));
178 /* Can we release the page from the cache? */
179 if (!ceph_release_fscache_page(page
, g
))
182 return !PagePrivate(page
);
186 * read a single page, without unlocking it.
188 static int readpage_nounlock(struct file
*filp
, struct page
*page
)
190 struct inode
*inode
= file_inode(filp
);
191 struct ceph_inode_info
*ci
= ceph_inode(inode
);
192 struct ceph_osd_client
*osdc
=
193 &ceph_inode_to_client(inode
)->client
->osdc
;
195 u64 off
= page_offset(page
);
196 u64 len
= PAGE_CACHE_SIZE
;
198 if (off
>= i_size_read(inode
)) {
199 zero_user_segment(page
, err
, PAGE_CACHE_SIZE
);
200 SetPageUptodate(page
);
205 * Uptodate inline data should have been added into page cache
206 * while getting Fcr caps.
208 if (ci
->i_inline_version
!= CEPH_INLINE_NONE
)
211 err
= ceph_readpage_from_fscache(inode
, page
);
215 dout("readpage inode %p file %p page %p index %lu\n",
216 inode
, filp
, page
, page
->index
);
217 err
= ceph_osdc_readpages(osdc
, ceph_vino(inode
), &ci
->i_layout
,
219 ci
->i_truncate_seq
, ci
->i_truncate_size
,
225 ceph_fscache_readpage_cancel(inode
, page
);
228 if (err
< PAGE_CACHE_SIZE
)
229 /* zero fill remainder of page */
230 zero_user_segment(page
, err
, PAGE_CACHE_SIZE
);
232 flush_dcache_page(page
);
234 SetPageUptodate(page
);
235 ceph_readpage_to_fscache(inode
, page
);
238 return err
< 0 ? err
: 0;
241 static int ceph_readpage(struct file
*filp
, struct page
*page
)
243 int r
= readpage_nounlock(filp
, page
);
249 * Finish an async read(ahead) op.
251 static void finish_read(struct ceph_osd_request
*req
, struct ceph_msg
*msg
)
253 struct inode
*inode
= req
->r_inode
;
254 struct ceph_osd_data
*osd_data
;
255 int rc
= req
->r_result
;
256 int bytes
= le32_to_cpu(msg
->hdr
.data_len
);
260 dout("finish_read %p req %p rc %d bytes %d\n", inode
, req
, rc
, bytes
);
262 /* unlock all pages, zeroing any data we didn't read */
263 osd_data
= osd_req_op_extent_osd_data(req
, 0);
264 BUG_ON(osd_data
->type
!= CEPH_OSD_DATA_TYPE_PAGES
);
265 num_pages
= calc_pages_for((u64
)osd_data
->alignment
,
266 (u64
)osd_data
->length
);
267 for (i
= 0; i
< num_pages
; i
++) {
268 struct page
*page
= osd_data
->pages
[i
];
272 if (bytes
< (int)PAGE_CACHE_SIZE
) {
273 /* zero (remainder of) page */
274 int s
= bytes
< 0 ? 0 : bytes
;
275 zero_user_segment(page
, s
, PAGE_CACHE_SIZE
);
277 dout("finish_read %p uptodate %p idx %lu\n", inode
, page
,
279 flush_dcache_page(page
);
280 SetPageUptodate(page
);
281 ceph_readpage_to_fscache(inode
, page
);
284 page_cache_release(page
);
285 bytes
-= PAGE_CACHE_SIZE
;
287 kfree(osd_data
->pages
);
290 static void ceph_unlock_page_vector(struct page
**pages
, int num_pages
)
294 for (i
= 0; i
< num_pages
; i
++)
295 unlock_page(pages
[i
]);
299 * start an async read(ahead) operation. return nr_pages we submitted
300 * a read for on success, or negative error code.
302 static int start_read(struct inode
*inode
, struct list_head
*page_list
, int max
)
304 struct ceph_osd_client
*osdc
=
305 &ceph_inode_to_client(inode
)->client
->osdc
;
306 struct ceph_inode_info
*ci
= ceph_inode(inode
);
307 struct page
*page
= list_entry(page_list
->prev
, struct page
, lru
);
308 struct ceph_vino vino
;
309 struct ceph_osd_request
*req
;
318 off
= (u64
) page_offset(page
);
321 next_index
= page
->index
;
322 list_for_each_entry_reverse(page
, page_list
, lru
) {
323 if (page
->index
!= next_index
)
327 if (max
&& nr_pages
== max
)
330 len
= nr_pages
<< PAGE_CACHE_SHIFT
;
331 dout("start_read %p nr_pages %d is %lld~%lld\n", inode
, nr_pages
,
333 vino
= ceph_vino(inode
);
334 req
= ceph_osdc_new_request(osdc
, &ci
->i_layout
, vino
, off
, &len
,
335 0, 1, CEPH_OSD_OP_READ
,
336 CEPH_OSD_FLAG_READ
, NULL
,
337 ci
->i_truncate_seq
, ci
->i_truncate_size
,
342 /* build page vector */
343 nr_pages
= calc_pages_for(0, len
);
344 pages
= kmalloc(sizeof(*pages
) * nr_pages
, GFP_NOFS
);
348 for (i
= 0; i
< nr_pages
; ++i
) {
349 page
= list_entry(page_list
->prev
, struct page
, lru
);
350 BUG_ON(PageLocked(page
));
351 list_del(&page
->lru
);
353 dout("start_read %p adding %p idx %lu\n", inode
, page
,
355 if (add_to_page_cache_lru(page
, &inode
->i_data
, page
->index
,
357 ceph_fscache_uncache_page(inode
, page
);
358 page_cache_release(page
);
359 dout("start_read %p add_to_page_cache failed %p\n",
366 osd_req_op_extent_osd_data_pages(req
, 0, pages
, len
, 0, false, false);
367 req
->r_callback
= finish_read
;
368 req
->r_inode
= inode
;
370 ceph_osdc_build_request(req
, off
, NULL
, vino
.snap
, NULL
);
372 dout("start_read %p starting %p %lld~%lld\n", inode
, req
, off
, len
);
373 ret
= ceph_osdc_start_request(osdc
, req
, false);
376 ceph_osdc_put_request(req
);
380 ceph_unlock_page_vector(pages
, nr_pages
);
381 ceph_release_page_vector(pages
, nr_pages
);
383 ceph_osdc_put_request(req
);
389 * Read multiple pages. Leave pages we don't read + unlock in page_list;
390 * the caller (VM) cleans them up.
392 static int ceph_readpages(struct file
*file
, struct address_space
*mapping
,
393 struct list_head
*page_list
, unsigned nr_pages
)
395 struct inode
*inode
= file_inode(file
);
396 struct ceph_fs_client
*fsc
= ceph_inode_to_client(inode
);
400 if (ceph_inode(inode
)->i_inline_version
!= CEPH_INLINE_NONE
)
403 rc
= ceph_readpages_from_fscache(mapping
->host
, mapping
, page_list
,
409 if (fsc
->mount_options
->rsize
>= PAGE_CACHE_SIZE
)
410 max
= (fsc
->mount_options
->rsize
+ PAGE_CACHE_SIZE
- 1)
413 dout("readpages %p file %p nr_pages %d max %d\n", inode
,
416 while (!list_empty(page_list
)) {
417 rc
= start_read(inode
, page_list
, max
);
423 ceph_fscache_readpages_cancel(inode
, page_list
);
425 dout("readpages %p file %p ret %d\n", inode
, file
, rc
);
430 * Get ref for the oldest snapc for an inode with dirty data... that is, the
431 * only snap context we are allowed to write back.
433 static struct ceph_snap_context
*get_oldest_context(struct inode
*inode
,
436 struct ceph_inode_info
*ci
= ceph_inode(inode
);
437 struct ceph_snap_context
*snapc
= NULL
;
438 struct ceph_cap_snap
*capsnap
= NULL
;
440 spin_lock(&ci
->i_ceph_lock
);
441 list_for_each_entry(capsnap
, &ci
->i_cap_snaps
, ci_item
) {
442 dout(" cap_snap %p snapc %p has %d dirty pages\n", capsnap
,
443 capsnap
->context
, capsnap
->dirty_pages
);
444 if (capsnap
->dirty_pages
) {
445 snapc
= ceph_get_snap_context(capsnap
->context
);
447 *snap_size
= capsnap
->size
;
451 if (!snapc
&& ci
->i_wrbuffer_ref_head
) {
452 snapc
= ceph_get_snap_context(ci
->i_head_snapc
);
453 dout(" head snapc %p has %d dirty pages\n",
454 snapc
, ci
->i_wrbuffer_ref_head
);
456 spin_unlock(&ci
->i_ceph_lock
);
461 * Write a single page, but leave the page locked.
463 * If we get a write error, set the page error bit, but still adjust the
464 * dirty page accounting (i.e., page is no longer dirty).
466 static int writepage_nounlock(struct page
*page
, struct writeback_control
*wbc
)
469 struct ceph_inode_info
*ci
;
470 struct ceph_fs_client
*fsc
;
471 struct ceph_osd_client
*osdc
;
472 struct ceph_snap_context
*snapc
, *oldest
;
473 loff_t page_off
= page_offset(page
);
475 u64 truncate_size
, snap_size
= 0;
477 int err
= 0, len
= PAGE_CACHE_SIZE
;
479 dout("writepage %p idx %lu\n", page
, page
->index
);
481 if (!page
->mapping
|| !page
->mapping
->host
) {
482 dout("writepage %p - no mapping\n", page
);
485 inode
= page
->mapping
->host
;
486 ci
= ceph_inode(inode
);
487 fsc
= ceph_inode_to_client(inode
);
488 osdc
= &fsc
->client
->osdc
;
490 /* verify this is a writeable snap context */
491 snapc
= page_snap_context(page
);
493 dout("writepage %p page %p not dirty?\n", inode
, page
);
496 oldest
= get_oldest_context(inode
, &snap_size
);
497 if (snapc
->seq
> oldest
->seq
) {
498 dout("writepage %p page %p snapc %p not writeable - noop\n",
500 /* we should only noop if called by kswapd */
501 WARN_ON((current
->flags
& PF_MEMALLOC
) == 0);
502 ceph_put_snap_context(oldest
);
505 ceph_put_snap_context(oldest
);
507 spin_lock(&ci
->i_ceph_lock
);
508 truncate_seq
= ci
->i_truncate_seq
;
509 truncate_size
= ci
->i_truncate_size
;
511 snap_size
= i_size_read(inode
);
512 spin_unlock(&ci
->i_ceph_lock
);
514 /* is this a partial page at end of file? */
515 if (page_off
>= snap_size
) {
516 dout("%p page eof %llu\n", page
, snap_size
);
519 if (snap_size
< page_off
+ len
)
520 len
= snap_size
- page_off
;
522 dout("writepage %p page %p index %lu on %llu~%u snapc %p\n",
523 inode
, page
, page
->index
, page_off
, len
, snapc
);
525 writeback_stat
= atomic_long_inc_return(&fsc
->writeback_count
);
527 CONGESTION_ON_THRESH(fsc
->mount_options
->congestion_kb
))
528 set_bdi_congested(&fsc
->backing_dev_info
, BLK_RW_ASYNC
);
530 ceph_readpage_to_fscache(inode
, page
);
532 set_page_writeback(page
);
533 err
= ceph_osdc_writepages(osdc
, ceph_vino(inode
),
534 &ci
->i_layout
, snapc
,
536 truncate_seq
, truncate_size
,
537 &inode
->i_mtime
, &page
, 1);
539 dout("writepage setting page/mapping error %d %p\n", err
, page
);
541 mapping_set_error(&inode
->i_data
, err
);
543 wbc
->pages_skipped
++;
545 dout("writepage cleaned page %p\n", page
);
546 err
= 0; /* vfs expects us to return 0 */
549 ClearPagePrivate(page
);
550 end_page_writeback(page
);
551 ceph_put_wrbuffer_cap_refs(ci
, 1, snapc
);
552 ceph_put_snap_context(snapc
); /* page's reference */
557 static int ceph_writepage(struct page
*page
, struct writeback_control
*wbc
)
560 struct inode
*inode
= page
->mapping
->host
;
563 err
= writepage_nounlock(page
, wbc
);
571 * lame release_pages helper. release_pages() isn't exported to
574 static void ceph_release_pages(struct page
**pages
, int num
)
579 pagevec_init(&pvec
, 0);
580 for (i
= 0; i
< num
; i
++) {
581 if (pagevec_add(&pvec
, pages
[i
]) == 0)
582 pagevec_release(&pvec
);
584 pagevec_release(&pvec
);
588 * async writeback completion handler.
590 * If we get an error, set the mapping error bit, but not the individual
593 static void writepages_finish(struct ceph_osd_request
*req
,
594 struct ceph_msg
*msg
)
596 struct inode
*inode
= req
->r_inode
;
597 struct ceph_inode_info
*ci
= ceph_inode(inode
);
598 struct ceph_osd_data
*osd_data
;
603 struct ceph_snap_context
*snapc
= req
->r_snapc
;
604 struct address_space
*mapping
= inode
->i_mapping
;
605 int rc
= req
->r_result
;
606 u64 bytes
= req
->r_ops
[0].extent
.length
;
607 struct ceph_fs_client
*fsc
= ceph_inode_to_client(inode
);
609 unsigned issued
= ceph_caps_issued(ci
);
611 osd_data
= osd_req_op_extent_osd_data(req
, 0);
612 BUG_ON(osd_data
->type
!= CEPH_OSD_DATA_TYPE_PAGES
);
613 num_pages
= calc_pages_for((u64
)osd_data
->alignment
,
614 (u64
)osd_data
->length
);
617 * Assume we wrote the pages we originally sent. The
618 * osd might reply with fewer pages if our writeback
619 * raced with a truncation and was adjusted at the osd,
620 * so don't believe the reply.
625 mapping_set_error(mapping
, rc
);
627 dout("writepages_finish %p rc %d bytes %llu wrote %d (pages)\n",
628 inode
, rc
, bytes
, wrote
);
630 /* clean all pages */
631 for (i
= 0; i
< num_pages
; i
++) {
632 page
= osd_data
->pages
[i
];
634 WARN_ON(!PageUptodate(page
));
637 atomic_long_dec_return(&fsc
->writeback_count
);
639 CONGESTION_OFF_THRESH(fsc
->mount_options
->congestion_kb
))
640 clear_bdi_congested(&fsc
->backing_dev_info
,
643 ceph_put_snap_context(page_snap_context(page
));
645 ClearPagePrivate(page
);
646 dout("unlocking %d %p\n", i
, page
);
647 end_page_writeback(page
);
650 * We lost the cache cap, need to truncate the page before
651 * it is unlocked, otherwise we'd truncate it later in the
652 * page truncation thread, possibly losing some data that
655 if ((issued
& (CEPH_CAP_FILE_CACHE
|CEPH_CAP_FILE_LAZYIO
)) == 0)
656 generic_error_remove_page(inode
->i_mapping
, page
);
660 dout("%p wrote+cleaned %d pages\n", inode
, wrote
);
661 ceph_put_wrbuffer_cap_refs(ci
, num_pages
, snapc
);
663 ceph_release_pages(osd_data
->pages
, num_pages
);
664 if (osd_data
->pages_from_pool
)
665 mempool_free(osd_data
->pages
,
666 ceph_sb_to_client(inode
->i_sb
)->wb_pagevec_pool
);
668 kfree(osd_data
->pages
);
669 ceph_osdc_put_request(req
);
673 * initiate async writeback
675 static int ceph_writepages_start(struct address_space
*mapping
,
676 struct writeback_control
*wbc
)
678 struct inode
*inode
= mapping
->host
;
679 struct ceph_inode_info
*ci
= ceph_inode(inode
);
680 struct ceph_fs_client
*fsc
= ceph_inode_to_client(inode
);
681 struct ceph_vino vino
= ceph_vino(inode
);
682 pgoff_t index
, start
, end
;
685 pgoff_t max_pages
= 0, max_pages_ever
= 0;
686 struct ceph_snap_context
*snapc
= NULL
, *last_snapc
= NULL
, *pgsnapc
;
690 unsigned wsize
= 1 << inode
->i_blkbits
;
691 struct ceph_osd_request
*req
= NULL
;
693 u64 truncate_size
, snap_size
;
697 * Include a 'sync' in the OSD request if this is a data
698 * integrity write (e.g., O_SYNC write or fsync()), or if our
699 * cap is being revoked.
701 if ((wbc
->sync_mode
== WB_SYNC_ALL
) ||
702 ceph_caps_revoking(ci
, CEPH_CAP_FILE_BUFFER
))
704 dout("writepages_start %p dosync=%d (mode=%s)\n",
706 wbc
->sync_mode
== WB_SYNC_NONE
? "NONE" :
707 (wbc
->sync_mode
== WB_SYNC_ALL
? "ALL" : "HOLD"));
709 if (fsc
->mount_state
== CEPH_MOUNT_SHUTDOWN
) {
710 pr_warn("writepage_start %p on forced umount\n", inode
);
711 return -EIO
; /* we're in a forced umount, don't write! */
713 if (fsc
->mount_options
->wsize
&& fsc
->mount_options
->wsize
< wsize
)
714 wsize
= fsc
->mount_options
->wsize
;
715 if (wsize
< PAGE_CACHE_SIZE
)
716 wsize
= PAGE_CACHE_SIZE
;
717 max_pages_ever
= wsize
>> PAGE_CACHE_SHIFT
;
719 pagevec_init(&pvec
, 0);
721 /* where to start/end? */
722 if (wbc
->range_cyclic
) {
723 start
= mapping
->writeback_index
; /* Start from prev offset */
725 dout(" cyclic, start at %lu\n", start
);
727 start
= wbc
->range_start
>> PAGE_CACHE_SHIFT
;
728 end
= wbc
->range_end
>> PAGE_CACHE_SHIFT
;
729 if (wbc
->range_start
== 0 && wbc
->range_end
== LLONG_MAX
)
732 dout(" not cyclic, %lu to %lu\n", start
, end
);
737 /* find oldest snap context with dirty data */
738 ceph_put_snap_context(snapc
);
740 snapc
= get_oldest_context(inode
, &snap_size
);
742 /* hmm, why does writepages get called when there
744 dout(" no snap context with dirty data?\n");
748 snap_size
= i_size_read(inode
);
749 dout(" oldest snapc is %p seq %lld (%d snaps)\n",
750 snapc
, snapc
->seq
, snapc
->num_snaps
);
752 spin_lock(&ci
->i_ceph_lock
);
753 truncate_seq
= ci
->i_truncate_seq
;
754 truncate_size
= ci
->i_truncate_size
;
756 snap_size
= i_size_read(inode
);
757 spin_unlock(&ci
->i_ceph_lock
);
759 if (last_snapc
&& snapc
!= last_snapc
) {
760 /* if we switched to a newer snapc, restart our scan at the
761 * start of the original file range. */
762 dout(" snapc differs from last pass, restarting at %lu\n",
768 while (!done
&& index
<= end
) {
772 int pvec_pages
, locked_pages
;
773 struct page
**pages
= NULL
;
774 mempool_t
*pool
= NULL
; /* Becomes non-null if mempool used */
782 max_pages
= max_pages_ever
;
786 want
= min(end
- index
,
787 min((pgoff_t
)PAGEVEC_SIZE
,
788 max_pages
- (pgoff_t
)locked_pages
) - 1)
790 pvec_pages
= pagevec_lookup_tag(&pvec
, mapping
, &index
,
793 dout("pagevec_lookup_tag got %d\n", pvec_pages
);
794 if (!pvec_pages
&& !locked_pages
)
796 for (i
= 0; i
< pvec_pages
&& locked_pages
< max_pages
; i
++) {
797 page
= pvec
.pages
[i
];
798 dout("? %p idx %lu\n", page
, page
->index
);
799 if (locked_pages
== 0)
800 lock_page(page
); /* first page */
801 else if (!trylock_page(page
))
804 /* only dirty pages, or our accounting breaks */
805 if (unlikely(!PageDirty(page
)) ||
806 unlikely(page
->mapping
!= mapping
)) {
807 dout("!dirty or !mapping %p\n", page
);
811 if (!wbc
->range_cyclic
&& page
->index
> end
) {
812 dout("end of range %p\n", page
);
817 if (next
&& (page
->index
!= next
)) {
818 dout("not consecutive %p\n", page
);
822 if (wbc
->sync_mode
!= WB_SYNC_NONE
) {
823 dout("waiting on writeback %p\n", page
);
824 wait_on_page_writeback(page
);
826 if (page_offset(page
) >= snap_size
) {
827 dout("%p page eof %llu\n", page
, snap_size
);
832 if (PageWriteback(page
)) {
833 dout("%p under writeback\n", page
);
838 /* only if matching snap context */
839 pgsnapc
= page_snap_context(page
);
840 if (pgsnapc
->seq
> snapc
->seq
) {
841 dout("page snapc %p %lld > oldest %p %lld\n",
842 pgsnapc
, pgsnapc
->seq
, snapc
, snapc
->seq
);
845 continue; /* keep looking for snap */
849 if (!clear_page_dirty_for_io(page
)) {
850 dout("%p !clear_page_dirty_for_io\n", page
);
856 * We have something to write. If this is
857 * the first locked page this time through,
858 * allocate an osd request and a page array
861 if (locked_pages
== 0) {
863 /* prepare async write request */
864 offset
= (u64
)page_offset(page
);
866 req
= ceph_osdc_new_request(&fsc
->client
->osdc
,
871 CEPH_OSD_FLAG_WRITE
|
872 CEPH_OSD_FLAG_ONDISK
,
874 truncate_size
, true);
882 osd_req_op_init(req
, 1, CEPH_OSD_OP_STARTSYNC
);
884 req
->r_callback
= writepages_finish
;
885 req
->r_inode
= inode
;
887 max_pages
= calc_pages_for(0, (u64
)len
);
888 pages
= kmalloc(max_pages
* sizeof (*pages
),
891 pool
= fsc
->wb_pagevec_pool
;
892 pages
= mempool_alloc(pool
, GFP_NOFS
);
897 /* note position of first page in pvec */
900 dout("%p will write page %p idx %lu\n",
901 inode
, page
, page
->index
);
904 atomic_long_inc_return(&fsc
->writeback_count
);
905 if (writeback_stat
> CONGESTION_ON_THRESH(
906 fsc
->mount_options
->congestion_kb
)) {
907 set_bdi_congested(&fsc
->backing_dev_info
,
911 set_page_writeback(page
);
912 pages
[locked_pages
] = page
;
914 next
= page
->index
+ 1;
917 /* did we get anything? */
919 goto release_pvec_pages
;
922 BUG_ON(!locked_pages
|| first
< 0);
924 if (pvec_pages
&& i
== pvec_pages
&&
925 locked_pages
< max_pages
) {
926 dout("reached end pvec, trying for more\n");
927 pagevec_reinit(&pvec
);
931 /* shift unused pages over in the pvec... we
932 * will need to release them below. */
933 for (j
= i
; j
< pvec_pages
; j
++) {
934 dout(" pvec leftover page %p\n",
936 pvec
.pages
[j
-i
+first
] = pvec
.pages
[j
];
941 /* Format the osd request message and submit the write */
943 offset
= page_offset(pages
[0]);
944 len
= min(snap_size
- offset
,
945 (u64
)locked_pages
<< PAGE_CACHE_SHIFT
);
946 dout("writepages got %d pages at %llu~%llu\n",
947 locked_pages
, offset
, len
);
949 osd_req_op_extent_osd_data_pages(req
, 0, pages
, len
, 0,
952 pages
= NULL
; /* request message now owns the pages array */
955 /* Update the write op length in case we changed it */
957 osd_req_op_extent_update(req
, 0, len
);
959 vino
= ceph_vino(inode
);
960 ceph_osdc_build_request(req
, offset
, snapc
, vino
.snap
,
963 rc
= ceph_osdc_start_request(&fsc
->client
->osdc
, req
, true);
969 wbc
->nr_to_write
-= locked_pages
;
970 if (wbc
->nr_to_write
<= 0)
974 dout("pagevec_release on %d pages (%p)\n", (int)pvec
.nr
,
975 pvec
.nr
? pvec
.pages
[0] : NULL
);
976 pagevec_release(&pvec
);
978 if (locked_pages
&& !done
)
982 if (should_loop
&& !done
) {
983 /* more to do; loop back to beginning of file */
984 dout("writepages looping back to beginning of file\n");
990 if (wbc
->range_cyclic
|| (range_whole
&& wbc
->nr_to_write
> 0))
991 mapping
->writeback_index
= index
;
995 ceph_osdc_put_request(req
);
996 ceph_put_snap_context(snapc
);
997 dout("writepages done, rc = %d\n", rc
);
1004 * See if a given @snapc is either writeable, or already written.
1006 static int context_is_writeable_or_written(struct inode
*inode
,
1007 struct ceph_snap_context
*snapc
)
1009 struct ceph_snap_context
*oldest
= get_oldest_context(inode
, NULL
);
1010 int ret
= !oldest
|| snapc
->seq
<= oldest
->seq
;
1012 ceph_put_snap_context(oldest
);
1017 * We are only allowed to write into/dirty the page if the page is
1018 * clean, or already dirty within the same snap context.
1020 * called with page locked.
1021 * return success with page locked,
1022 * or any failure (incl -EAGAIN) with page unlocked.
1024 static int ceph_update_writeable_page(struct file
*file
,
1025 loff_t pos
, unsigned len
,
1028 struct inode
*inode
= file_inode(file
);
1029 struct ceph_inode_info
*ci
= ceph_inode(inode
);
1030 struct ceph_mds_client
*mdsc
= ceph_inode_to_client(inode
)->mdsc
;
1031 loff_t page_off
= pos
& PAGE_CACHE_MASK
;
1032 int pos_in_page
= pos
& ~PAGE_CACHE_MASK
;
1033 int end_in_page
= pos_in_page
+ len
;
1036 struct ceph_snap_context
*snapc
, *oldest
;
1039 /* writepages currently holds page lock, but if we change that later, */
1040 wait_on_page_writeback(page
);
1042 /* check snap context */
1043 BUG_ON(!ci
->i_snap_realm
);
1044 down_read(&mdsc
->snap_rwsem
);
1045 BUG_ON(!ci
->i_snap_realm
->cached_context
);
1046 snapc
= page_snap_context(page
);
1047 if (snapc
&& snapc
!= ci
->i_head_snapc
) {
1049 * this page is already dirty in another (older) snap
1050 * context! is it writeable now?
1052 oldest
= get_oldest_context(inode
, NULL
);
1053 up_read(&mdsc
->snap_rwsem
);
1055 if (snapc
->seq
> oldest
->seq
) {
1056 ceph_put_snap_context(oldest
);
1057 dout(" page %p snapc %p not current or oldest\n",
1060 * queue for writeback, and wait for snapc to
1061 * be writeable or written
1063 snapc
= ceph_get_snap_context(snapc
);
1065 ceph_queue_writeback(inode
);
1066 r
= wait_event_interruptible(ci
->i_cap_wq
,
1067 context_is_writeable_or_written(inode
, snapc
));
1068 ceph_put_snap_context(snapc
);
1069 if (r
== -ERESTARTSYS
)
1073 ceph_put_snap_context(oldest
);
1075 /* yay, writeable, do it now (without dropping page lock) */
1076 dout(" page %p snapc %p not current, but oldest\n",
1078 if (!clear_page_dirty_for_io(page
))
1080 r
= writepage_nounlock(page
, NULL
);
1086 if (PageUptodate(page
)) {
1087 dout(" page %p already uptodate\n", page
);
1092 if (pos_in_page
== 0 && len
== PAGE_CACHE_SIZE
)
1095 /* past end of file? */
1096 i_size
= inode
->i_size
; /* caller holds i_mutex */
1098 if (page_off
>= i_size
||
1099 (pos_in_page
== 0 && (pos
+len
) >= i_size
&&
1100 end_in_page
- pos_in_page
!= PAGE_CACHE_SIZE
)) {
1101 dout(" zeroing %p 0 - %d and %d - %d\n",
1102 page
, pos_in_page
, end_in_page
, (int)PAGE_CACHE_SIZE
);
1103 zero_user_segments(page
,
1105 end_in_page
, PAGE_CACHE_SIZE
);
1109 /* we need to read it. */
1110 up_read(&mdsc
->snap_rwsem
);
1111 r
= readpage_nounlock(file
, page
);
1121 * We are only allowed to write into/dirty the page if the page is
1122 * clean, or already dirty within the same snap context.
1124 static int ceph_write_begin(struct file
*file
, struct address_space
*mapping
,
1125 loff_t pos
, unsigned len
, unsigned flags
,
1126 struct page
**pagep
, void **fsdata
)
1128 struct inode
*inode
= file_inode(file
);
1130 pgoff_t index
= pos
>> PAGE_CACHE_SHIFT
;
1135 page
= grab_cache_page_write_begin(mapping
, index
, 0);
1140 dout("write_begin file %p inode %p page %p %d~%d\n", file
,
1141 inode
, page
, (int)pos
, (int)len
);
1143 r
= ceph_update_writeable_page(file
, pos
, len
, page
);
1144 } while (r
== -EAGAIN
);
1150 * we don't do anything in here that simple_write_end doesn't do
1151 * except adjust dirty page accounting and drop read lock on
1154 static int ceph_write_end(struct file
*file
, struct address_space
*mapping
,
1155 loff_t pos
, unsigned len
, unsigned copied
,
1156 struct page
*page
, void *fsdata
)
1158 struct inode
*inode
= file_inode(file
);
1159 struct ceph_fs_client
*fsc
= ceph_inode_to_client(inode
);
1160 struct ceph_mds_client
*mdsc
= fsc
->mdsc
;
1161 unsigned from
= pos
& (PAGE_CACHE_SIZE
- 1);
1164 dout("write_end file %p inode %p page %p %d~%d (%d)\n", file
,
1165 inode
, page
, (int)pos
, (int)copied
, (int)len
);
1167 /* zero the stale part of the page if we did a short copy */
1169 zero_user_segment(page
, from
+copied
, len
);
1171 /* did file size increase? */
1172 /* (no need for i_size_read(); we caller holds i_mutex */
1173 if (pos
+copied
> inode
->i_size
)
1174 check_cap
= ceph_inode_set_size(inode
, pos
+copied
);
1176 if (!PageUptodate(page
))
1177 SetPageUptodate(page
);
1179 set_page_dirty(page
);
1182 up_read(&mdsc
->snap_rwsem
);
1183 page_cache_release(page
);
1186 ceph_check_caps(ceph_inode(inode
), CHECK_CAPS_AUTHONLY
, NULL
);
1192 * we set .direct_IO to indicate direct io is supported, but since we
1193 * intercept O_DIRECT reads and writes early, this function should
1196 static ssize_t
ceph_direct_io(int rw
, struct kiocb
*iocb
,
1197 struct iov_iter
*iter
,
1204 const struct address_space_operations ceph_aops
= {
1205 .readpage
= ceph_readpage
,
1206 .readpages
= ceph_readpages
,
1207 .writepage
= ceph_writepage
,
1208 .writepages
= ceph_writepages_start
,
1209 .write_begin
= ceph_write_begin
,
1210 .write_end
= ceph_write_end
,
1211 .set_page_dirty
= ceph_set_page_dirty
,
1212 .invalidatepage
= ceph_invalidatepage
,
1213 .releasepage
= ceph_releasepage
,
1214 .direct_IO
= ceph_direct_io
,
1221 static int ceph_filemap_fault(struct vm_area_struct
*vma
, struct vm_fault
*vmf
)
1223 struct inode
*inode
= file_inode(vma
->vm_file
);
1224 struct ceph_inode_info
*ci
= ceph_inode(inode
);
1225 struct ceph_file_info
*fi
= vma
->vm_file
->private_data
;
1226 struct page
*pinned_page
= NULL
;
1227 loff_t off
= vmf
->pgoff
<< PAGE_CACHE_SHIFT
;
1230 dout("filemap_fault %p %llx.%llx %llu~%zd trying to get caps\n",
1231 inode
, ceph_vinop(inode
), off
, (size_t)PAGE_CACHE_SIZE
);
1232 if (fi
->fmode
& CEPH_FILE_MODE_LAZY
)
1233 want
= CEPH_CAP_FILE_CACHE
| CEPH_CAP_FILE_LAZYIO
;
1235 want
= CEPH_CAP_FILE_CACHE
;
1238 ret
= ceph_get_caps(ci
, CEPH_CAP_FILE_RD
, want
,
1239 -1, &got
, &pinned_page
);
1242 if (ret
!= -ERESTARTSYS
) {
1244 return VM_FAULT_SIGBUS
;
1247 dout("filemap_fault %p %llu~%zd got cap refs on %s\n",
1248 inode
, off
, (size_t)PAGE_CACHE_SIZE
, ceph_cap_string(got
));
1250 if ((got
& (CEPH_CAP_FILE_CACHE
| CEPH_CAP_FILE_LAZYIO
)) ||
1251 ci
->i_inline_version
== CEPH_INLINE_NONE
)
1252 ret
= filemap_fault(vma
, vmf
);
1256 dout("filemap_fault %p %llu~%zd dropping cap refs on %s ret %d\n",
1257 inode
, off
, (size_t)PAGE_CACHE_SIZE
, ceph_cap_string(got
), ret
);
1259 page_cache_release(pinned_page
);
1260 ceph_put_cap_refs(ci
, got
);
1265 /* read inline data */
1266 if (off
>= PAGE_CACHE_SIZE
) {
1267 /* does not support inline data > PAGE_SIZE */
1268 ret
= VM_FAULT_SIGBUS
;
1271 struct address_space
*mapping
= inode
->i_mapping
;
1272 struct page
*page
= find_or_create_page(mapping
, 0,
1273 mapping_gfp_mask(mapping
) &
1279 ret1
= __ceph_do_getattr(inode
, page
,
1280 CEPH_STAT_CAP_INLINE_DATA
, true);
1281 if (ret1
< 0 || off
>= i_size_read(inode
)) {
1283 page_cache_release(page
);
1284 ret
= VM_FAULT_SIGBUS
;
1287 if (ret1
< PAGE_CACHE_SIZE
)
1288 zero_user_segment(page
, ret1
, PAGE_CACHE_SIZE
);
1290 flush_dcache_page(page
);
1291 SetPageUptodate(page
);
1293 ret
= VM_FAULT_MAJOR
| VM_FAULT_LOCKED
;
1296 dout("filemap_fault %p %llu~%zd read inline data ret %d\n",
1297 inode
, off
, (size_t)PAGE_CACHE_SIZE
, ret
);
1302 * Reuse write_begin here for simplicity.
1304 static int ceph_page_mkwrite(struct vm_area_struct
*vma
, struct vm_fault
*vmf
)
1306 struct inode
*inode
= file_inode(vma
->vm_file
);
1307 struct ceph_inode_info
*ci
= ceph_inode(inode
);
1308 struct ceph_file_info
*fi
= vma
->vm_file
->private_data
;
1309 struct ceph_mds_client
*mdsc
= ceph_inode_to_client(inode
)->mdsc
;
1310 struct page
*page
= vmf
->page
;
1311 loff_t off
= page_offset(page
);
1312 loff_t size
= i_size_read(inode
);
1316 if (ci
->i_inline_version
!= CEPH_INLINE_NONE
) {
1317 struct page
*locked_page
= NULL
;
1322 ret
= ceph_uninline_data(vma
->vm_file
, locked_page
);
1324 unlock_page(locked_page
);
1326 return VM_FAULT_SIGBUS
;
1329 if (off
+ PAGE_CACHE_SIZE
<= size
)
1330 len
= PAGE_CACHE_SIZE
;
1332 len
= size
& ~PAGE_CACHE_MASK
;
1334 dout("page_mkwrite %p %llx.%llx %llu~%zd getting caps i_size %llu\n",
1335 inode
, ceph_vinop(inode
), off
, len
, size
);
1336 if (fi
->fmode
& CEPH_FILE_MODE_LAZY
)
1337 want
= CEPH_CAP_FILE_BUFFER
| CEPH_CAP_FILE_LAZYIO
;
1339 want
= CEPH_CAP_FILE_BUFFER
;
1342 ret
= ceph_get_caps(ci
, CEPH_CAP_FILE_WR
, want
, off
+ len
,
1346 if (ret
!= -ERESTARTSYS
) {
1348 return VM_FAULT_SIGBUS
;
1351 dout("page_mkwrite %p %llu~%zd got cap refs on %s\n",
1352 inode
, off
, len
, ceph_cap_string(got
));
1354 /* Update time before taking page lock */
1355 file_update_time(vma
->vm_file
);
1359 ret
= VM_FAULT_NOPAGE
;
1361 (page
->mapping
!= inode
->i_mapping
))
1364 ret
= ceph_update_writeable_page(vma
->vm_file
, off
, len
, page
);
1366 /* success. we'll keep the page locked. */
1367 set_page_dirty(page
);
1368 up_read(&mdsc
->snap_rwsem
);
1369 ret
= VM_FAULT_LOCKED
;
1374 ret
= VM_FAULT_SIGBUS
;
1377 if (ret
!= VM_FAULT_LOCKED
)
1379 if (ret
== VM_FAULT_LOCKED
||
1380 ci
->i_inline_version
!= CEPH_INLINE_NONE
) {
1382 spin_lock(&ci
->i_ceph_lock
);
1383 ci
->i_inline_version
= CEPH_INLINE_NONE
;
1384 dirty
= __ceph_mark_dirty_caps(ci
, CEPH_CAP_FILE_WR
);
1385 spin_unlock(&ci
->i_ceph_lock
);
1387 __mark_inode_dirty(inode
, dirty
);
1390 dout("page_mkwrite %p %llu~%zd dropping cap refs on %s ret %d\n",
1391 inode
, off
, len
, ceph_cap_string(got
), ret
);
1392 ceph_put_cap_refs(ci
, got
);
1397 void ceph_fill_inline_data(struct inode
*inode
, struct page
*locked_page
,
1398 char *data
, size_t len
)
1400 struct address_space
*mapping
= inode
->i_mapping
;
1406 if (i_size_read(inode
) == 0)
1408 page
= find_or_create_page(mapping
, 0,
1409 mapping_gfp_mask(mapping
) & ~__GFP_FS
);
1412 if (PageUptodate(page
)) {
1414 page_cache_release(page
);
1419 dout("fill_inline_data %p %llx.%llx len %zu locked_page %p\n",
1420 inode
, ceph_vinop(inode
), len
, locked_page
);
1423 void *kaddr
= kmap_atomic(page
);
1424 memcpy(kaddr
, data
, len
);
1425 kunmap_atomic(kaddr
);
1428 if (page
!= locked_page
) {
1429 if (len
< PAGE_CACHE_SIZE
)
1430 zero_user_segment(page
, len
, PAGE_CACHE_SIZE
);
1432 flush_dcache_page(page
);
1434 SetPageUptodate(page
);
1436 page_cache_release(page
);
1440 int ceph_uninline_data(struct file
*filp
, struct page
*locked_page
)
1442 struct inode
*inode
= file_inode(filp
);
1443 struct ceph_inode_info
*ci
= ceph_inode(inode
);
1444 struct ceph_fs_client
*fsc
= ceph_inode_to_client(inode
);
1445 struct ceph_osd_request
*req
;
1446 struct page
*page
= NULL
;
1447 u64 len
, inline_version
;
1449 bool from_pagecache
= false;
1451 spin_lock(&ci
->i_ceph_lock
);
1452 inline_version
= ci
->i_inline_version
;
1453 spin_unlock(&ci
->i_ceph_lock
);
1455 dout("uninline_data %p %llx.%llx inline_version %llu\n",
1456 inode
, ceph_vinop(inode
), inline_version
);
1458 if (inline_version
== 1 || /* initial version, no data */
1459 inline_version
== CEPH_INLINE_NONE
)
1464 WARN_ON(!PageUptodate(page
));
1465 } else if (ceph_caps_issued(ci
) &
1466 (CEPH_CAP_FILE_CACHE
|CEPH_CAP_FILE_LAZYIO
)) {
1467 page
= find_get_page(inode
->i_mapping
, 0);
1469 if (PageUptodate(page
)) {
1470 from_pagecache
= true;
1473 page_cache_release(page
);
1480 len
= i_size_read(inode
);
1481 if (len
> PAGE_CACHE_SIZE
)
1482 len
= PAGE_CACHE_SIZE
;
1484 page
= __page_cache_alloc(GFP_NOFS
);
1489 err
= __ceph_do_getattr(inode
, page
,
1490 CEPH_STAT_CAP_INLINE_DATA
, true);
1492 /* no inline data */
1493 if (err
== -ENODATA
)
1500 req
= ceph_osdc_new_request(&fsc
->client
->osdc
, &ci
->i_layout
,
1501 ceph_vino(inode
), 0, &len
, 0, 1,
1503 CEPH_OSD_FLAG_ONDISK
| CEPH_OSD_FLAG_WRITE
,
1504 ci
->i_snap_realm
->cached_context
,
1511 ceph_osdc_build_request(req
, 0, NULL
, CEPH_NOSNAP
, &inode
->i_mtime
);
1512 err
= ceph_osdc_start_request(&fsc
->client
->osdc
, req
, false);
1514 err
= ceph_osdc_wait_request(&fsc
->client
->osdc
, req
);
1515 ceph_osdc_put_request(req
);
1519 req
= ceph_osdc_new_request(&fsc
->client
->osdc
, &ci
->i_layout
,
1520 ceph_vino(inode
), 0, &len
, 1, 3,
1522 CEPH_OSD_FLAG_ONDISK
| CEPH_OSD_FLAG_WRITE
,
1523 ci
->i_snap_realm
->cached_context
,
1524 ci
->i_truncate_seq
, ci
->i_truncate_size
,
1531 osd_req_op_extent_osd_data_pages(req
, 1, &page
, len
, 0, false, false);
1533 err
= osd_req_op_xattr_init(req
, 0, CEPH_OSD_OP_CMPXATTR
,
1534 "inline_version", &inline_version
,
1535 sizeof(inline_version
),
1536 CEPH_OSD_CMPXATTR_OP_GT
,
1537 CEPH_OSD_CMPXATTR_MODE_U64
);
1541 err
= osd_req_op_xattr_init(req
, 2, CEPH_OSD_OP_SETXATTR
,
1542 "inline_version", &inline_version
,
1543 sizeof(inline_version
), 0, 0);
1547 ceph_osdc_build_request(req
, 0, NULL
, CEPH_NOSNAP
, &inode
->i_mtime
);
1548 err
= ceph_osdc_start_request(&fsc
->client
->osdc
, req
, false);
1550 err
= ceph_osdc_wait_request(&fsc
->client
->osdc
, req
);
1552 ceph_osdc_put_request(req
);
1553 if (err
== -ECANCELED
)
1556 if (page
&& page
!= locked_page
) {
1557 if (from_pagecache
) {
1559 page_cache_release(page
);
1561 __free_pages(page
, 0);
1564 dout("uninline_data %p %llx.%llx inline_version %llu = %d\n",
1565 inode
, ceph_vinop(inode
), inline_version
, err
);
1569 static struct vm_operations_struct ceph_vmops
= {
1570 .fault
= ceph_filemap_fault
,
1571 .page_mkwrite
= ceph_page_mkwrite
,
1572 .remap_pages
= generic_file_remap_pages
,
1575 int ceph_mmap(struct file
*file
, struct vm_area_struct
*vma
)
1577 struct address_space
*mapping
= file
->f_mapping
;
1579 if (!mapping
->a_ops
->readpage
)
1581 file_accessed(file
);
1582 vma
->vm_ops
= &ceph_vmops
;