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1#include <linux/ceph/ceph_debug.h>
2
3#include <linux/backing-dev.h>
4#include <linux/fs.h>
5#include <linux/mm.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>
11
12#include "super.h"
13#include "mds_client.h"
14#include <linux/ceph/osd_client.h>
15
16/*
17 * Ceph address space ops.
18 *
19 * There are a few funny things going on here.
20 *
21 * The page->private field is used to reference a struct
22 * ceph_snap_context for _every_ dirty page. This indicates which
23 * snapshot the page was logically dirtied in, and thus which snap
24 * context needs to be associated with the osd write during writeback.
25 *
26 * Similarly, struct ceph_inode_info maintains a set of counters to
27 * count dirty pages on the inode. In the absence of snapshots,
28 * i_wrbuffer_ref == i_wrbuffer_ref_head == the dirty page count.
29 *
30 * When a snapshot is taken (that is, when the client receives
31 * notification that a snapshot was taken), each inode with caps and
32 * with dirty pages (dirty pages implies there is a cap) gets a new
33 * ceph_cap_snap in the i_cap_snaps list (which is sorted in ascending
34 * order, new snaps go to the tail). The i_wrbuffer_ref_head count is
35 * moved to capsnap->dirty. (Unless a sync write is currently in
36 * progress. In that case, the capsnap is said to be "pending", new
37 * writes cannot start, and the capsnap isn't "finalized" until the
38 * write completes (or fails) and a final size/mtime for the inode for
39 * that snap can be settled upon.) i_wrbuffer_ref_head is reset to 0.
40 *
41 * On writeback, we must submit writes to the osd IN SNAP ORDER. So,
42 * we look for the first capsnap in i_cap_snaps and write out pages in
43 * that snap context _only_. Then we move on to the next capsnap,
44 * eventually reaching the "live" or "head" context (i.e., pages that
45 * are not yet snapped) and are writing the most recently dirtied
46 * pages.
47 *
48 * Invalidate and so forth must take care to ensure the dirty page
49 * accounting is preserved.
50 */
51
52#define CONGESTION_ON_THRESH(congestion_kb) (congestion_kb >> (PAGE_SHIFT-10))
53#define CONGESTION_OFF_THRESH(congestion_kb) \
54 (CONGESTION_ON_THRESH(congestion_kb) - \
55 (CONGESTION_ON_THRESH(congestion_kb) >> 2))
56
57
58
59/*
60 * Dirty a page. Optimistically adjust accounting, on the assumption
61 * that we won't race with invalidate. If we do, readjust.
62 */
63static int ceph_set_page_dirty(struct page *page)
64{
65 struct address_space *mapping = page->mapping;
66 struct inode *inode;
67 struct ceph_inode_info *ci;
68 int undo = 0;
69 struct ceph_snap_context *snapc;
70
71 if (unlikely(!mapping))
72 return !TestSetPageDirty(page);
73
74 if (TestSetPageDirty(page)) {
75 dout("%p set_page_dirty %p idx %lu -- already dirty\n",
76 mapping->host, page, page->index);
77 return 0;
78 }
79
80 inode = mapping->host;
81 ci = ceph_inode(inode);
82
83 /*
84 * Note that we're grabbing a snapc ref here without holding
85 * any locks!
86 */
87 snapc = ceph_get_snap_context(ci->i_snap_realm->cached_context);
88
89 /* dirty the head */
90 spin_lock(&inode->i_lock);
91 if (ci->i_head_snapc == NULL)
92 ci->i_head_snapc = ceph_get_snap_context(snapc);
93 ++ci->i_wrbuffer_ref_head;
94 if (ci->i_wrbuffer_ref == 0)
95 ihold(inode);
96 ++ci->i_wrbuffer_ref;
97 dout("%p set_page_dirty %p idx %lu head %d/%d -> %d/%d "
98 "snapc %p seq %lld (%d snaps)\n",
99 mapping->host, page, page->index,
100 ci->i_wrbuffer_ref-1, ci->i_wrbuffer_ref_head-1,
101 ci->i_wrbuffer_ref, ci->i_wrbuffer_ref_head,
102 snapc, snapc->seq, snapc->num_snaps);
103 spin_unlock(&inode->i_lock);
104
105 /* now adjust page */
106 spin_lock_irq(&mapping->tree_lock);
107 if (page->mapping) { /* Race with truncate? */
108 WARN_ON_ONCE(!PageUptodate(page));
109 account_page_dirtied(page, page->mapping);
110 radix_tree_tag_set(&mapping->page_tree,
111 page_index(page), PAGECACHE_TAG_DIRTY);
112
113 /*
114 * Reference snap context in page->private. Also set
115 * PagePrivate so that we get invalidatepage callback.
116 */
117 page->private = (unsigned long)snapc;
118 SetPagePrivate(page);
119 } else {
120 dout("ANON set_page_dirty %p (raced truncate?)\n", page);
121 undo = 1;
122 }
123
124 spin_unlock_irq(&mapping->tree_lock);
125
126 if (undo)
127 /* whoops, we failed to dirty the page */
128 ceph_put_wrbuffer_cap_refs(ci, 1, snapc);
129
130 __mark_inode_dirty(mapping->host, I_DIRTY_PAGES);
131
132 BUG_ON(!PageDirty(page));
133 return 1;
134}
135
136/*
137 * If we are truncating the full page (i.e. offset == 0), adjust the
138 * dirty page counters appropriately. Only called if there is private
139 * data on the page.
140 */
141static void ceph_invalidatepage(struct page *page, unsigned long offset)
142{
143 struct inode *inode;
144 struct ceph_inode_info *ci;
145 struct ceph_snap_context *snapc = (void *)page->private;
146
147 BUG_ON(!PageLocked(page));
148 BUG_ON(!page->private);
149 BUG_ON(!PagePrivate(page));
150 BUG_ON(!page->mapping);
151
152 inode = page->mapping->host;
153
154 /*
155 * We can get non-dirty pages here due to races between
156 * set_page_dirty and truncate_complete_page; just spit out a
157 * warning, in case we end up with accounting problems later.
158 */
159 if (!PageDirty(page))
160 pr_err("%p invalidatepage %p page not dirty\n", inode, page);
161
162 if (offset == 0)
163 ClearPageChecked(page);
164
165 ci = ceph_inode(inode);
166 if (offset == 0) {
167 dout("%p invalidatepage %p idx %lu full dirty page %lu\n",
168 inode, page, page->index, offset);
169 ceph_put_wrbuffer_cap_refs(ci, 1, snapc);
170 ceph_put_snap_context(snapc);
171 page->private = 0;
172 ClearPagePrivate(page);
173 } else {
174 dout("%p invalidatepage %p idx %lu partial dirty page\n",
175 inode, page, page->index);
176 }
177}
178
179/* just a sanity check */
180static int ceph_releasepage(struct page *page, gfp_t g)
181{
182 struct inode *inode = page->mapping ? page->mapping->host : NULL;
183 dout("%p releasepage %p idx %lu\n", inode, page, page->index);
184 WARN_ON(PageDirty(page));
185 WARN_ON(page->private);
186 WARN_ON(PagePrivate(page));
187 return 0;
188}
189
190/*
191 * read a single page, without unlocking it.
192 */
193static int readpage_nounlock(struct file *filp, struct page *page)
194{
195 struct inode *inode = filp->f_dentry->d_inode;
196 struct ceph_inode_info *ci = ceph_inode(inode);
197 struct ceph_osd_client *osdc =
198 &ceph_inode_to_client(inode)->client->osdc;
199 int err = 0;
200 u64 len = PAGE_CACHE_SIZE;
201
202 dout("readpage inode %p file %p page %p index %lu\n",
203 inode, filp, page, page->index);
204 err = ceph_osdc_readpages(osdc, ceph_vino(inode), &ci->i_layout,
205 page->index << PAGE_CACHE_SHIFT, &len,
206 ci->i_truncate_seq, ci->i_truncate_size,
207 &page, 1, 0);
208 if (err == -ENOENT)
209 err = 0;
210 if (err < 0) {
211 SetPageError(page);
212 goto out;
213 } else if (err < PAGE_CACHE_SIZE) {
214 /* zero fill remainder of page */
215 zero_user_segment(page, err, PAGE_CACHE_SIZE);
216 }
217 SetPageUptodate(page);
218
219out:
220 return err < 0 ? err : 0;
221}
222
223static int ceph_readpage(struct file *filp, struct page *page)
224{
225 int r = readpage_nounlock(filp, page);
226 unlock_page(page);
227 return r;
228}
229
230/*
231 * Build a vector of contiguous pages from the provided page list.
232 */
233static struct page **page_vector_from_list(struct list_head *page_list,
234 unsigned *nr_pages)
235{
236 struct page **pages;
237 struct page *page;
238 int next_index, contig_pages = 0;
239
240 /* build page vector */
241 pages = kmalloc(sizeof(*pages) * *nr_pages, GFP_NOFS);
242 if (!pages)
243 return ERR_PTR(-ENOMEM);
244
245 BUG_ON(list_empty(page_list));
246 next_index = list_entry(page_list->prev, struct page, lru)->index;
247 list_for_each_entry_reverse(page, page_list, lru) {
248 if (page->index == next_index) {
249 dout("readpages page %d %p\n", contig_pages, page);
250 pages[contig_pages] = page;
251 contig_pages++;
252 next_index++;
253 } else {
254 break;
255 }
256 }
257 *nr_pages = contig_pages;
258 return pages;
259}
260
261/*
262 * Read multiple pages. Leave pages we don't read + unlock in page_list;
263 * the caller (VM) cleans them up.
264 */
265static int ceph_readpages(struct file *file, struct address_space *mapping,
266 struct list_head *page_list, unsigned nr_pages)
267{
268 struct inode *inode = file->f_dentry->d_inode;
269 struct ceph_inode_info *ci = ceph_inode(inode);
270 struct ceph_osd_client *osdc =
271 &ceph_inode_to_client(inode)->client->osdc;
272 int rc = 0;
273 struct page **pages;
274 loff_t offset;
275 u64 len;
276
277 dout("readpages %p file %p nr_pages %d\n",
278 inode, file, nr_pages);
279
280 pages = page_vector_from_list(page_list, &nr_pages);
281 if (IS_ERR(pages))
282 return PTR_ERR(pages);
283
284 /* guess read extent */
285 offset = pages[0]->index << PAGE_CACHE_SHIFT;
286 len = nr_pages << PAGE_CACHE_SHIFT;
287 rc = ceph_osdc_readpages(osdc, ceph_vino(inode), &ci->i_layout,
288 offset, &len,
289 ci->i_truncate_seq, ci->i_truncate_size,
290 pages, nr_pages, 0);
291 if (rc == -ENOENT)
292 rc = 0;
293 if (rc < 0)
294 goto out;
295
296 for (; !list_empty(page_list) && len > 0;
297 rc -= PAGE_CACHE_SIZE, len -= PAGE_CACHE_SIZE) {
298 struct page *page =
299 list_entry(page_list->prev, struct page, lru);
300
301 list_del(&page->lru);
302
303 if (rc < (int)PAGE_CACHE_SIZE) {
304 /* zero (remainder of) page */
305 int s = rc < 0 ? 0 : rc;
306 zero_user_segment(page, s, PAGE_CACHE_SIZE);
307 }
308
309 if (add_to_page_cache_lru(page, mapping, page->index,
310 GFP_NOFS)) {
311 page_cache_release(page);
312 dout("readpages %p add_to_page_cache failed %p\n",
313 inode, page);
314 continue;
315 }
316 dout("readpages %p adding %p idx %lu\n", inode, page,
317 page->index);
318 flush_dcache_page(page);
319 SetPageUptodate(page);
320 unlock_page(page);
321 page_cache_release(page);
322 }
323 rc = 0;
324
325out:
326 kfree(pages);
327 return rc;
328}
329
330/*
331 * Get ref for the oldest snapc for an inode with dirty data... that is, the
332 * only snap context we are allowed to write back.
333 */
334static struct ceph_snap_context *get_oldest_context(struct inode *inode,
335 u64 *snap_size)
336{
337 struct ceph_inode_info *ci = ceph_inode(inode);
338 struct ceph_snap_context *snapc = NULL;
339 struct ceph_cap_snap *capsnap = NULL;
340
341 spin_lock(&inode->i_lock);
342 list_for_each_entry(capsnap, &ci->i_cap_snaps, ci_item) {
343 dout(" cap_snap %p snapc %p has %d dirty pages\n", capsnap,
344 capsnap->context, capsnap->dirty_pages);
345 if (capsnap->dirty_pages) {
346 snapc = ceph_get_snap_context(capsnap->context);
347 if (snap_size)
348 *snap_size = capsnap->size;
349 break;
350 }
351 }
352 if (!snapc && ci->i_wrbuffer_ref_head) {
353 snapc = ceph_get_snap_context(ci->i_head_snapc);
354 dout(" head snapc %p has %d dirty pages\n",
355 snapc, ci->i_wrbuffer_ref_head);
356 }
357 spin_unlock(&inode->i_lock);
358 return snapc;
359}
360
361/*
362 * Write a single page, but leave the page locked.
363 *
364 * If we get a write error, set the page error bit, but still adjust the
365 * dirty page accounting (i.e., page is no longer dirty).
366 */
367static int writepage_nounlock(struct page *page, struct writeback_control *wbc)
368{
369 struct inode *inode;
370 struct ceph_inode_info *ci;
371 struct ceph_fs_client *fsc;
372 struct ceph_osd_client *osdc;
373 loff_t page_off = page->index << PAGE_CACHE_SHIFT;
374 int len = PAGE_CACHE_SIZE;
375 loff_t i_size;
376 int err = 0;
377 struct ceph_snap_context *snapc, *oldest;
378 u64 snap_size = 0;
379 long writeback_stat;
380
381 dout("writepage %p idx %lu\n", page, page->index);
382
383 if (!page->mapping || !page->mapping->host) {
384 dout("writepage %p - no mapping\n", page);
385 return -EFAULT;
386 }
387 inode = page->mapping->host;
388 ci = ceph_inode(inode);
389 fsc = ceph_inode_to_client(inode);
390 osdc = &fsc->client->osdc;
391
392 /* verify this is a writeable snap context */
393 snapc = (void *)page->private;
394 if (snapc == NULL) {
395 dout("writepage %p page %p not dirty?\n", inode, page);
396 goto out;
397 }
398 oldest = get_oldest_context(inode, &snap_size);
399 if (snapc->seq > oldest->seq) {
400 dout("writepage %p page %p snapc %p not writeable - noop\n",
401 inode, page, (void *)page->private);
402 /* we should only noop if called by kswapd */
403 WARN_ON((current->flags & PF_MEMALLOC) == 0);
404 ceph_put_snap_context(oldest);
405 goto out;
406 }
407 ceph_put_snap_context(oldest);
408
409 /* is this a partial page at end of file? */
410 if (snap_size)
411 i_size = snap_size;
412 else
413 i_size = i_size_read(inode);
414 if (i_size < page_off + len)
415 len = i_size - page_off;
416
417 dout("writepage %p page %p index %lu on %llu~%u snapc %p\n",
418 inode, page, page->index, page_off, len, snapc);
419
420 writeback_stat = atomic_long_inc_return(&fsc->writeback_count);
421 if (writeback_stat >
422 CONGESTION_ON_THRESH(fsc->mount_options->congestion_kb))
423 set_bdi_congested(&fsc->backing_dev_info, BLK_RW_ASYNC);
424
425 set_page_writeback(page);
426 err = ceph_osdc_writepages(osdc, ceph_vino(inode),
427 &ci->i_layout, snapc,
428 page_off, len,
429 ci->i_truncate_seq, ci->i_truncate_size,
430 &inode->i_mtime,
431 &page, 1, 0, 0, true);
432 if (err < 0) {
433 dout("writepage setting page/mapping error %d %p\n", err, page);
434 SetPageError(page);
435 mapping_set_error(&inode->i_data, err);
436 if (wbc)
437 wbc->pages_skipped++;
438 } else {
439 dout("writepage cleaned page %p\n", page);
440 err = 0; /* vfs expects us to return 0 */
441 }
442 page->private = 0;
443 ClearPagePrivate(page);
444 end_page_writeback(page);
445 ceph_put_wrbuffer_cap_refs(ci, 1, snapc);
446 ceph_put_snap_context(snapc); /* page's reference */
447out:
448 return err;
449}
450
451static int ceph_writepage(struct page *page, struct writeback_control *wbc)
452{
453 int err;
454 struct inode *inode = page->mapping->host;
455 BUG_ON(!inode);
456 ihold(inode);
457 err = writepage_nounlock(page, wbc);
458 unlock_page(page);
459 iput(inode);
460 return err;
461}
462
463
464/*
465 * lame release_pages helper. release_pages() isn't exported to
466 * modules.
467 */
468static void ceph_release_pages(struct page **pages, int num)
469{
470 struct pagevec pvec;
471 int i;
472
473 pagevec_init(&pvec, 0);
474 for (i = 0; i < num; i++) {
475 if (pagevec_add(&pvec, pages[i]) == 0)
476 pagevec_release(&pvec);
477 }
478 pagevec_release(&pvec);
479}
480
481
482/*
483 * async writeback completion handler.
484 *
485 * If we get an error, set the mapping error bit, but not the individual
486 * page error bits.
487 */
488static void writepages_finish(struct ceph_osd_request *req,
489 struct ceph_msg *msg)
490{
491 struct inode *inode = req->r_inode;
492 struct ceph_osd_reply_head *replyhead;
493 struct ceph_osd_op *op;
494 struct ceph_inode_info *ci = ceph_inode(inode);
495 unsigned wrote;
496 struct page *page;
497 int i;
498 struct ceph_snap_context *snapc = req->r_snapc;
499 struct address_space *mapping = inode->i_mapping;
500 __s32 rc = -EIO;
501 u64 bytes = 0;
502 struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
503 long writeback_stat;
504 unsigned issued = ceph_caps_issued(ci);
505
506 /* parse reply */
507 replyhead = msg->front.iov_base;
508 WARN_ON(le32_to_cpu(replyhead->num_ops) == 0);
509 op = (void *)(replyhead + 1);
510 rc = le32_to_cpu(replyhead->result);
511 bytes = le64_to_cpu(op->extent.length);
512
513 if (rc >= 0) {
514 /*
515 * Assume we wrote the pages we originally sent. The
516 * osd might reply with fewer pages if our writeback
517 * raced with a truncation and was adjusted at the osd,
518 * so don't believe the reply.
519 */
520 wrote = req->r_num_pages;
521 } else {
522 wrote = 0;
523 mapping_set_error(mapping, rc);
524 }
525 dout("writepages_finish %p rc %d bytes %llu wrote %d (pages)\n",
526 inode, rc, bytes, wrote);
527
528 /* clean all pages */
529 for (i = 0; i < req->r_num_pages; i++) {
530 page = req->r_pages[i];
531 BUG_ON(!page);
532 WARN_ON(!PageUptodate(page));
533
534 writeback_stat =
535 atomic_long_dec_return(&fsc->writeback_count);
536 if (writeback_stat <
537 CONGESTION_OFF_THRESH(fsc->mount_options->congestion_kb))
538 clear_bdi_congested(&fsc->backing_dev_info,
539 BLK_RW_ASYNC);
540
541 ceph_put_snap_context((void *)page->private);
542 page->private = 0;
543 ClearPagePrivate(page);
544 dout("unlocking %d %p\n", i, page);
545 end_page_writeback(page);
546
547 /*
548 * We lost the cache cap, need to truncate the page before
549 * it is unlocked, otherwise we'd truncate it later in the
550 * page truncation thread, possibly losing some data that
551 * raced its way in
552 */
553 if ((issued & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)) == 0)
554 generic_error_remove_page(inode->i_mapping, page);
555
556 unlock_page(page);
557 }
558 dout("%p wrote+cleaned %d pages\n", inode, wrote);
559 ceph_put_wrbuffer_cap_refs(ci, req->r_num_pages, snapc);
560
561 ceph_release_pages(req->r_pages, req->r_num_pages);
562 if (req->r_pages_from_pool)
563 mempool_free(req->r_pages,
564 ceph_sb_to_client(inode->i_sb)->wb_pagevec_pool);
565 else
566 kfree(req->r_pages);
567 ceph_osdc_put_request(req);
568}
569
570/*
571 * allocate a page vec, either directly, or if necessary, via a the
572 * mempool. we avoid the mempool if we can because req->r_num_pages
573 * may be less than the maximum write size.
574 */
575static void alloc_page_vec(struct ceph_fs_client *fsc,
576 struct ceph_osd_request *req)
577{
578 req->r_pages = kmalloc(sizeof(struct page *) * req->r_num_pages,
579 GFP_NOFS);
580 if (!req->r_pages) {
581 req->r_pages = mempool_alloc(fsc->wb_pagevec_pool, GFP_NOFS);
582 req->r_pages_from_pool = 1;
583 WARN_ON(!req->r_pages);
584 }
585}
586
587/*
588 * initiate async writeback
589 */
590static int ceph_writepages_start(struct address_space *mapping,
591 struct writeback_control *wbc)
592{
593 struct inode *inode = mapping->host;
594 struct ceph_inode_info *ci = ceph_inode(inode);
595 struct ceph_fs_client *fsc;
596 pgoff_t index, start, end;
597 int range_whole = 0;
598 int should_loop = 1;
599 pgoff_t max_pages = 0, max_pages_ever = 0;
600 struct ceph_snap_context *snapc = NULL, *last_snapc = NULL, *pgsnapc;
601 struct pagevec pvec;
602 int done = 0;
603 int rc = 0;
604 unsigned wsize = 1 << inode->i_blkbits;
605 struct ceph_osd_request *req = NULL;
606 int do_sync;
607 u64 snap_size = 0;
608
609 /*
610 * Include a 'sync' in the OSD request if this is a data
611 * integrity write (e.g., O_SYNC write or fsync()), or if our
612 * cap is being revoked.
613 */
614 do_sync = wbc->sync_mode == WB_SYNC_ALL;
615 if (ceph_caps_revoking(ci, CEPH_CAP_FILE_BUFFER))
616 do_sync = 1;
617 dout("writepages_start %p dosync=%d (mode=%s)\n",
618 inode, do_sync,
619 wbc->sync_mode == WB_SYNC_NONE ? "NONE" :
620 (wbc->sync_mode == WB_SYNC_ALL ? "ALL" : "HOLD"));
621
622 fsc = ceph_inode_to_client(inode);
623 if (fsc->mount_state == CEPH_MOUNT_SHUTDOWN) {
624 pr_warning("writepage_start %p on forced umount\n", inode);
625 return -EIO; /* we're in a forced umount, don't write! */
626 }
627 if (fsc->mount_options->wsize && fsc->mount_options->wsize < wsize)
628 wsize = fsc->mount_options->wsize;
629 if (wsize < PAGE_CACHE_SIZE)
630 wsize = PAGE_CACHE_SIZE;
631 max_pages_ever = wsize >> PAGE_CACHE_SHIFT;
632
633 pagevec_init(&pvec, 0);
634
635 /* where to start/end? */
636 if (wbc->range_cyclic) {
637 start = mapping->writeback_index; /* Start from prev offset */
638 end = -1;
639 dout(" cyclic, start at %lu\n", start);
640 } else {
641 start = wbc->range_start >> PAGE_CACHE_SHIFT;
642 end = wbc->range_end >> PAGE_CACHE_SHIFT;
643 if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX)
644 range_whole = 1;
645 should_loop = 0;
646 dout(" not cyclic, %lu to %lu\n", start, end);
647 }
648 index = start;
649
650retry:
651 /* find oldest snap context with dirty data */
652 ceph_put_snap_context(snapc);
653 snapc = get_oldest_context(inode, &snap_size);
654 if (!snapc) {
655 /* hmm, why does writepages get called when there
656 is no dirty data? */
657 dout(" no snap context with dirty data?\n");
658 goto out;
659 }
660 dout(" oldest snapc is %p seq %lld (%d snaps)\n",
661 snapc, snapc->seq, snapc->num_snaps);
662 if (last_snapc && snapc != last_snapc) {
663 /* if we switched to a newer snapc, restart our scan at the
664 * start of the original file range. */
665 dout(" snapc differs from last pass, restarting at %lu\n",
666 index);
667 index = start;
668 }
669 last_snapc = snapc;
670
671 while (!done && index <= end) {
672 unsigned i;
673 int first;
674 pgoff_t next;
675 int pvec_pages, locked_pages;
676 struct page *page;
677 int want;
678 u64 offset, len;
679 struct ceph_osd_request_head *reqhead;
680 struct ceph_osd_op *op;
681 long writeback_stat;
682
683 next = 0;
684 locked_pages = 0;
685 max_pages = max_pages_ever;
686
687get_more_pages:
688 first = -1;
689 want = min(end - index,
690 min((pgoff_t)PAGEVEC_SIZE,
691 max_pages - (pgoff_t)locked_pages) - 1)
692 + 1;
693 pvec_pages = pagevec_lookup_tag(&pvec, mapping, &index,
694 PAGECACHE_TAG_DIRTY,
695 want);
696 dout("pagevec_lookup_tag got %d\n", pvec_pages);
697 if (!pvec_pages && !locked_pages)
698 break;
699 for (i = 0; i < pvec_pages && locked_pages < max_pages; i++) {
700 page = pvec.pages[i];
701 dout("? %p idx %lu\n", page, page->index);
702 if (locked_pages == 0)
703 lock_page(page); /* first page */
704 else if (!trylock_page(page))
705 break;
706
707 /* only dirty pages, or our accounting breaks */
708 if (unlikely(!PageDirty(page)) ||
709 unlikely(page->mapping != mapping)) {
710 dout("!dirty or !mapping %p\n", page);
711 unlock_page(page);
712 break;
713 }
714 if (!wbc->range_cyclic && page->index > end) {
715 dout("end of range %p\n", page);
716 done = 1;
717 unlock_page(page);
718 break;
719 }
720 if (next && (page->index != next)) {
721 dout("not consecutive %p\n", page);
722 unlock_page(page);
723 break;
724 }
725 if (wbc->sync_mode != WB_SYNC_NONE) {
726 dout("waiting on writeback %p\n", page);
727 wait_on_page_writeback(page);
728 }
729 if ((snap_size && page_offset(page) > snap_size) ||
730 (!snap_size &&
731 page_offset(page) > i_size_read(inode))) {
732 dout("%p page eof %llu\n", page, snap_size ?
733 snap_size : i_size_read(inode));
734 done = 1;
735 unlock_page(page);
736 break;
737 }
738 if (PageWriteback(page)) {
739 dout("%p under writeback\n", page);
740 unlock_page(page);
741 break;
742 }
743
744 /* only if matching snap context */
745 pgsnapc = (void *)page->private;
746 if (pgsnapc->seq > snapc->seq) {
747 dout("page snapc %p %lld > oldest %p %lld\n",
748 pgsnapc, pgsnapc->seq, snapc, snapc->seq);
749 unlock_page(page);
750 if (!locked_pages)
751 continue; /* keep looking for snap */
752 break;
753 }
754
755 if (!clear_page_dirty_for_io(page)) {
756 dout("%p !clear_page_dirty_for_io\n", page);
757 unlock_page(page);
758 break;
759 }
760
761 /* ok */
762 if (locked_pages == 0) {
763 /* prepare async write request */
764 offset = (unsigned long long)page->index
765 << PAGE_CACHE_SHIFT;
766 len = wsize;
767 req = ceph_osdc_new_request(&fsc->client->osdc,
768 &ci->i_layout,
769 ceph_vino(inode),
770 offset, &len,
771 CEPH_OSD_OP_WRITE,
772 CEPH_OSD_FLAG_WRITE |
773 CEPH_OSD_FLAG_ONDISK,
774 snapc, do_sync,
775 ci->i_truncate_seq,
776 ci->i_truncate_size,
777 &inode->i_mtime, true, 1, 0);
778
779 if (!req) {
780 rc = -ENOMEM;
781 unlock_page(page);
782 break;
783 }
784
785 max_pages = req->r_num_pages;
786
787 alloc_page_vec(fsc, req);
788 req->r_callback = writepages_finish;
789 req->r_inode = inode;
790 }
791
792 /* note position of first page in pvec */
793 if (first < 0)
794 first = i;
795 dout("%p will write page %p idx %lu\n",
796 inode, page, page->index);
797
798 writeback_stat =
799 atomic_long_inc_return(&fsc->writeback_count);
800 if (writeback_stat > CONGESTION_ON_THRESH(
801 fsc->mount_options->congestion_kb)) {
802 set_bdi_congested(&fsc->backing_dev_info,
803 BLK_RW_ASYNC);
804 }
805
806 set_page_writeback(page);
807 req->r_pages[locked_pages] = page;
808 locked_pages++;
809 next = page->index + 1;
810 }
811
812 /* did we get anything? */
813 if (!locked_pages)
814 goto release_pvec_pages;
815 if (i) {
816 int j;
817 BUG_ON(!locked_pages || first < 0);
818
819 if (pvec_pages && i == pvec_pages &&
820 locked_pages < max_pages) {
821 dout("reached end pvec, trying for more\n");
822 pagevec_reinit(&pvec);
823 goto get_more_pages;
824 }
825
826 /* shift unused pages over in the pvec... we
827 * will need to release them below. */
828 for (j = i; j < pvec_pages; j++) {
829 dout(" pvec leftover page %p\n",
830 pvec.pages[j]);
831 pvec.pages[j-i+first] = pvec.pages[j];
832 }
833 pvec.nr -= i-first;
834 }
835
836 /* submit the write */
837 offset = req->r_pages[0]->index << PAGE_CACHE_SHIFT;
838 len = min((snap_size ? snap_size : i_size_read(inode)) - offset,
839 (u64)locked_pages << PAGE_CACHE_SHIFT);
840 dout("writepages got %d pages at %llu~%llu\n",
841 locked_pages, offset, len);
842
843 /* revise final length, page count */
844 req->r_num_pages = locked_pages;
845 reqhead = req->r_request->front.iov_base;
846 op = (void *)(reqhead + 1);
847 op->extent.length = cpu_to_le64(len);
848 op->payload_len = cpu_to_le32(len);
849 req->r_request->hdr.data_len = cpu_to_le32(len);
850
851 rc = ceph_osdc_start_request(&fsc->client->osdc, req, true);
852 BUG_ON(rc);
853 req = NULL;
854
855 /* continue? */
856 index = next;
857 wbc->nr_to_write -= locked_pages;
858 if (wbc->nr_to_write <= 0)
859 done = 1;
860
861release_pvec_pages:
862 dout("pagevec_release on %d pages (%p)\n", (int)pvec.nr,
863 pvec.nr ? pvec.pages[0] : NULL);
864 pagevec_release(&pvec);
865
866 if (locked_pages && !done)
867 goto retry;
868 }
869
870 if (should_loop && !done) {
871 /* more to do; loop back to beginning of file */
872 dout("writepages looping back to beginning of file\n");
873 should_loop = 0;
874 index = 0;
875 goto retry;
876 }
877
878 if (wbc->range_cyclic || (range_whole && wbc->nr_to_write > 0))
879 mapping->writeback_index = index;
880
881out:
882 if (req)
883 ceph_osdc_put_request(req);
884 ceph_put_snap_context(snapc);
885 dout("writepages done, rc = %d\n", rc);
886 return rc;
887}
888
889
890
891/*
892 * See if a given @snapc is either writeable, or already written.
893 */
894static int context_is_writeable_or_written(struct inode *inode,
895 struct ceph_snap_context *snapc)
896{
897 struct ceph_snap_context *oldest = get_oldest_context(inode, NULL);
898 int ret = !oldest || snapc->seq <= oldest->seq;
899
900 ceph_put_snap_context(oldest);
901 return ret;
902}
903
904/*
905 * We are only allowed to write into/dirty the page if the page is
906 * clean, or already dirty within the same snap context.
907 *
908 * called with page locked.
909 * return success with page locked,
910 * or any failure (incl -EAGAIN) with page unlocked.
911 */
912static int ceph_update_writeable_page(struct file *file,
913 loff_t pos, unsigned len,
914 struct page *page)
915{
916 struct inode *inode = file->f_dentry->d_inode;
917 struct ceph_inode_info *ci = ceph_inode(inode);
918 struct ceph_mds_client *mdsc = ceph_inode_to_client(inode)->mdsc;
919 loff_t page_off = pos & PAGE_CACHE_MASK;
920 int pos_in_page = pos & ~PAGE_CACHE_MASK;
921 int end_in_page = pos_in_page + len;
922 loff_t i_size;
923 int r;
924 struct ceph_snap_context *snapc, *oldest;
925
926retry_locked:
927 /* writepages currently holds page lock, but if we change that later, */
928 wait_on_page_writeback(page);
929
930 /* check snap context */
931 BUG_ON(!ci->i_snap_realm);
932 down_read(&mdsc->snap_rwsem);
933 BUG_ON(!ci->i_snap_realm->cached_context);
934 snapc = (void *)page->private;
935 if (snapc && snapc != ci->i_head_snapc) {
936 /*
937 * this page is already dirty in another (older) snap
938 * context! is it writeable now?
939 */
940 oldest = get_oldest_context(inode, NULL);
941 up_read(&mdsc->snap_rwsem);
942
943 if (snapc->seq > oldest->seq) {
944 ceph_put_snap_context(oldest);
945 dout(" page %p snapc %p not current or oldest\n",
946 page, snapc);
947 /*
948 * queue for writeback, and wait for snapc to
949 * be writeable or written
950 */
951 snapc = ceph_get_snap_context(snapc);
952 unlock_page(page);
953 ceph_queue_writeback(inode);
954 r = wait_event_interruptible(ci->i_cap_wq,
955 context_is_writeable_or_written(inode, snapc));
956 ceph_put_snap_context(snapc);
957 if (r == -ERESTARTSYS)
958 return r;
959 return -EAGAIN;
960 }
961 ceph_put_snap_context(oldest);
962
963 /* yay, writeable, do it now (without dropping page lock) */
964 dout(" page %p snapc %p not current, but oldest\n",
965 page, snapc);
966 if (!clear_page_dirty_for_io(page))
967 goto retry_locked;
968 r = writepage_nounlock(page, NULL);
969 if (r < 0)
970 goto fail_nosnap;
971 goto retry_locked;
972 }
973
974 if (PageUptodate(page)) {
975 dout(" page %p already uptodate\n", page);
976 return 0;
977 }
978
979 /* full page? */
980 if (pos_in_page == 0 && len == PAGE_CACHE_SIZE)
981 return 0;
982
983 /* past end of file? */
984 i_size = inode->i_size; /* caller holds i_mutex */
985
986 if (i_size + len > inode->i_sb->s_maxbytes) {
987 /* file is too big */
988 r = -EINVAL;
989 goto fail;
990 }
991
992 if (page_off >= i_size ||
993 (pos_in_page == 0 && (pos+len) >= i_size &&
994 end_in_page - pos_in_page != PAGE_CACHE_SIZE)) {
995 dout(" zeroing %p 0 - %d and %d - %d\n",
996 page, pos_in_page, end_in_page, (int)PAGE_CACHE_SIZE);
997 zero_user_segments(page,
998 0, pos_in_page,
999 end_in_page, PAGE_CACHE_SIZE);
1000 return 0;
1001 }
1002
1003 /* we need to read it. */
1004 up_read(&mdsc->snap_rwsem);
1005 r = readpage_nounlock(file, page);
1006 if (r < 0)
1007 goto fail_nosnap;
1008 goto retry_locked;
1009
1010fail:
1011 up_read(&mdsc->snap_rwsem);
1012fail_nosnap:
1013 unlock_page(page);
1014 return r;
1015}
1016
1017/*
1018 * We are only allowed to write into/dirty the page if the page is
1019 * clean, or already dirty within the same snap context.
1020 */
1021static int ceph_write_begin(struct file *file, struct address_space *mapping,
1022 loff_t pos, unsigned len, unsigned flags,
1023 struct page **pagep, void **fsdata)
1024{
1025 struct inode *inode = file->f_dentry->d_inode;
1026 struct page *page;
1027 pgoff_t index = pos >> PAGE_CACHE_SHIFT;
1028 int r;
1029
1030 do {
1031 /* get a page */
1032 page = grab_cache_page_write_begin(mapping, index, 0);
1033 if (!page)
1034 return -ENOMEM;
1035 *pagep = page;
1036
1037 dout("write_begin file %p inode %p page %p %d~%d\n", file,
1038 inode, page, (int)pos, (int)len);
1039
1040 r = ceph_update_writeable_page(file, pos, len, page);
1041 } while (r == -EAGAIN);
1042
1043 return r;
1044}
1045
1046/*
1047 * we don't do anything in here that simple_write_end doesn't do
1048 * except adjust dirty page accounting and drop read lock on
1049 * mdsc->snap_rwsem.
1050 */
1051static int ceph_write_end(struct file *file, struct address_space *mapping,
1052 loff_t pos, unsigned len, unsigned copied,
1053 struct page *page, void *fsdata)
1054{
1055 struct inode *inode = file->f_dentry->d_inode;
1056 struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
1057 struct ceph_mds_client *mdsc = fsc->mdsc;
1058 unsigned from = pos & (PAGE_CACHE_SIZE - 1);
1059 int check_cap = 0;
1060
1061 dout("write_end file %p inode %p page %p %d~%d (%d)\n", file,
1062 inode, page, (int)pos, (int)copied, (int)len);
1063
1064 /* zero the stale part of the page if we did a short copy */
1065 if (copied < len)
1066 zero_user_segment(page, from+copied, len);
1067
1068 /* did file size increase? */
1069 /* (no need for i_size_read(); we caller holds i_mutex */
1070 if (pos+copied > inode->i_size)
1071 check_cap = ceph_inode_set_size(inode, pos+copied);
1072
1073 if (!PageUptodate(page))
1074 SetPageUptodate(page);
1075
1076 set_page_dirty(page);
1077
1078 unlock_page(page);
1079 up_read(&mdsc->snap_rwsem);
1080 page_cache_release(page);
1081
1082 if (check_cap)
1083 ceph_check_caps(ceph_inode(inode), CHECK_CAPS_AUTHONLY, NULL);
1084
1085 return copied;
1086}
1087
1088/*
1089 * we set .direct_IO to indicate direct io is supported, but since we
1090 * intercept O_DIRECT reads and writes early, this function should
1091 * never get called.
1092 */
1093static ssize_t ceph_direct_io(int rw, struct kiocb *iocb,
1094 const struct iovec *iov,
1095 loff_t pos, unsigned long nr_segs)
1096{
1097 WARN_ON(1);
1098 return -EINVAL;
1099}
1100
1101const struct address_space_operations ceph_aops = {
1102 .readpage = ceph_readpage,
1103 .readpages = ceph_readpages,
1104 .writepage = ceph_writepage,
1105 .writepages = ceph_writepages_start,
1106 .write_begin = ceph_write_begin,
1107 .write_end = ceph_write_end,
1108 .set_page_dirty = ceph_set_page_dirty,
1109 .invalidatepage = ceph_invalidatepage,
1110 .releasepage = ceph_releasepage,
1111 .direct_IO = ceph_direct_io,
1112};
1113
1114
1115/*
1116 * vm ops
1117 */
1118
1119/*
1120 * Reuse write_begin here for simplicity.
1121 */
1122static int ceph_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
1123{
1124 struct inode *inode = vma->vm_file->f_dentry->d_inode;
1125 struct page *page = vmf->page;
1126 struct ceph_mds_client *mdsc = ceph_inode_to_client(inode)->mdsc;
1127 loff_t off = page->index << PAGE_CACHE_SHIFT;
1128 loff_t size, len;
1129 int ret;
1130
1131 size = i_size_read(inode);
1132 if (off + PAGE_CACHE_SIZE <= size)
1133 len = PAGE_CACHE_SIZE;
1134 else
1135 len = size & ~PAGE_CACHE_MASK;
1136
1137 dout("page_mkwrite %p %llu~%llu page %p idx %lu\n", inode,
1138 off, len, page, page->index);
1139
1140 lock_page(page);
1141
1142 ret = VM_FAULT_NOPAGE;
1143 if ((off > size) ||
1144 (page->mapping != inode->i_mapping))
1145 goto out;
1146
1147 ret = ceph_update_writeable_page(vma->vm_file, off, len, page);
1148 if (ret == 0) {
1149 /* success. we'll keep the page locked. */
1150 set_page_dirty(page);
1151 up_read(&mdsc->snap_rwsem);
1152 ret = VM_FAULT_LOCKED;
1153 } else {
1154 if (ret == -ENOMEM)
1155 ret = VM_FAULT_OOM;
1156 else
1157 ret = VM_FAULT_SIGBUS;
1158 }
1159out:
1160 dout("page_mkwrite %p %llu~%llu = %d\n", inode, off, len, ret);
1161 if (ret != VM_FAULT_LOCKED)
1162 unlock_page(page);
1163 return ret;
1164}
1165
1166static struct vm_operations_struct ceph_vmops = {
1167 .fault = filemap_fault,
1168 .page_mkwrite = ceph_page_mkwrite,
1169};
1170
1171int ceph_mmap(struct file *file, struct vm_area_struct *vma)
1172{
1173 struct address_space *mapping = file->f_mapping;
1174
1175 if (!mapping->a_ops->readpage)
1176 return -ENOEXEC;
1177 file_accessed(file);
1178 vma->vm_ops = &ceph_vmops;
1179 vma->vm_flags |= VM_CAN_NONLINEAR;
1180 return 0;
1181}
1// SPDX-License-Identifier: GPL-2.0
2#include <linux/ceph/ceph_debug.h>
3
4#include <linux/backing-dev.h>
5#include <linux/fs.h>
6#include <linux/mm.h>
7#include <linux/pagemap.h>
8#include <linux/writeback.h> /* generic_writepages */
9#include <linux/slab.h>
10#include <linux/pagevec.h>
11#include <linux/task_io_accounting_ops.h>
12#include <linux/signal.h>
13#include <linux/iversion.h>
14#include <linux/ktime.h>
15#include <linux/netfs.h>
16
17#include "super.h"
18#include "mds_client.h"
19#include "cache.h"
20#include "metric.h"
21#include <linux/ceph/osd_client.h>
22#include <linux/ceph/striper.h>
23
24/*
25 * Ceph address space ops.
26 *
27 * There are a few funny things going on here.
28 *
29 * The page->private field is used to reference a struct
30 * ceph_snap_context for _every_ dirty page. This indicates which
31 * snapshot the page was logically dirtied in, and thus which snap
32 * context needs to be associated with the osd write during writeback.
33 *
34 * Similarly, struct ceph_inode_info maintains a set of counters to
35 * count dirty pages on the inode. In the absence of snapshots,
36 * i_wrbuffer_ref == i_wrbuffer_ref_head == the dirty page count.
37 *
38 * When a snapshot is taken (that is, when the client receives
39 * notification that a snapshot was taken), each inode with caps and
40 * with dirty pages (dirty pages implies there is a cap) gets a new
41 * ceph_cap_snap in the i_cap_snaps list (which is sorted in ascending
42 * order, new snaps go to the tail). The i_wrbuffer_ref_head count is
43 * moved to capsnap->dirty. (Unless a sync write is currently in
44 * progress. In that case, the capsnap is said to be "pending", new
45 * writes cannot start, and the capsnap isn't "finalized" until the
46 * write completes (or fails) and a final size/mtime for the inode for
47 * that snap can be settled upon.) i_wrbuffer_ref_head is reset to 0.
48 *
49 * On writeback, we must submit writes to the osd IN SNAP ORDER. So,
50 * we look for the first capsnap in i_cap_snaps and write out pages in
51 * that snap context _only_. Then we move on to the next capsnap,
52 * eventually reaching the "live" or "head" context (i.e., pages that
53 * are not yet snapped) and are writing the most recently dirtied
54 * pages.
55 *
56 * Invalidate and so forth must take care to ensure the dirty page
57 * accounting is preserved.
58 */
59
60#define CONGESTION_ON_THRESH(congestion_kb) (congestion_kb >> (PAGE_SHIFT-10))
61#define CONGESTION_OFF_THRESH(congestion_kb) \
62 (CONGESTION_ON_THRESH(congestion_kb) - \
63 (CONGESTION_ON_THRESH(congestion_kb) >> 2))
64
65static int ceph_netfs_check_write_begin(struct file *file, loff_t pos, unsigned int len,
66 struct page *page, void **_fsdata);
67
68static inline struct ceph_snap_context *page_snap_context(struct page *page)
69{
70 if (PagePrivate(page))
71 return (void *)page->private;
72 return NULL;
73}
74
75/*
76 * Dirty a page. Optimistically adjust accounting, on the assumption
77 * that we won't race with invalidate. If we do, readjust.
78 */
79static int ceph_set_page_dirty(struct page *page)
80{
81 struct address_space *mapping = page->mapping;
82 struct inode *inode;
83 struct ceph_inode_info *ci;
84 struct ceph_snap_context *snapc;
85
86 if (PageDirty(page)) {
87 dout("%p set_page_dirty %p idx %lu -- already dirty\n",
88 mapping->host, page, page->index);
89 BUG_ON(!PagePrivate(page));
90 return 0;
91 }
92
93 inode = mapping->host;
94 ci = ceph_inode(inode);
95
96 /* dirty the head */
97 spin_lock(&ci->i_ceph_lock);
98 BUG_ON(ci->i_wr_ref == 0); // caller should hold Fw reference
99 if (__ceph_have_pending_cap_snap(ci)) {
100 struct ceph_cap_snap *capsnap =
101 list_last_entry(&ci->i_cap_snaps,
102 struct ceph_cap_snap,
103 ci_item);
104 snapc = ceph_get_snap_context(capsnap->context);
105 capsnap->dirty_pages++;
106 } else {
107 BUG_ON(!ci->i_head_snapc);
108 snapc = ceph_get_snap_context(ci->i_head_snapc);
109 ++ci->i_wrbuffer_ref_head;
110 }
111 if (ci->i_wrbuffer_ref == 0)
112 ihold(inode);
113 ++ci->i_wrbuffer_ref;
114 dout("%p set_page_dirty %p idx %lu head %d/%d -> %d/%d "
115 "snapc %p seq %lld (%d snaps)\n",
116 mapping->host, page, page->index,
117 ci->i_wrbuffer_ref-1, ci->i_wrbuffer_ref_head-1,
118 ci->i_wrbuffer_ref, ci->i_wrbuffer_ref_head,
119 snapc, snapc->seq, snapc->num_snaps);
120 spin_unlock(&ci->i_ceph_lock);
121
122 /*
123 * Reference snap context in page->private. Also set
124 * PagePrivate so that we get invalidatepage callback.
125 */
126 BUG_ON(PagePrivate(page));
127 attach_page_private(page, snapc);
128
129 return __set_page_dirty_nobuffers(page);
130}
131
132/*
133 * If we are truncating the full page (i.e. offset == 0), adjust the
134 * dirty page counters appropriately. Only called if there is private
135 * data on the page.
136 */
137static void ceph_invalidatepage(struct page *page, unsigned int offset,
138 unsigned int length)
139{
140 struct inode *inode;
141 struct ceph_inode_info *ci;
142 struct ceph_snap_context *snapc;
143
144 wait_on_page_fscache(page);
145
146 inode = page->mapping->host;
147 ci = ceph_inode(inode);
148
149 if (offset != 0 || length != thp_size(page)) {
150 dout("%p invalidatepage %p idx %lu partial dirty page %u~%u\n",
151 inode, page, page->index, offset, length);
152 return;
153 }
154
155 WARN_ON(!PageLocked(page));
156 if (!PagePrivate(page))
157 return;
158
159 dout("%p invalidatepage %p idx %lu full dirty page\n",
160 inode, page, page->index);
161
162 snapc = detach_page_private(page);
163 ceph_put_wrbuffer_cap_refs(ci, 1, snapc);
164 ceph_put_snap_context(snapc);
165}
166
167static int ceph_releasepage(struct page *page, gfp_t gfp)
168{
169 dout("%p releasepage %p idx %lu (%sdirty)\n", page->mapping->host,
170 page, page->index, PageDirty(page) ? "" : "not ");
171
172 if (PageFsCache(page)) {
173 if (!(gfp & __GFP_DIRECT_RECLAIM) || !(gfp & __GFP_FS))
174 return 0;
175 wait_on_page_fscache(page);
176 }
177 return !PagePrivate(page);
178}
179
180static void ceph_netfs_expand_readahead(struct netfs_read_request *rreq)
181{
182 struct inode *inode = rreq->mapping->host;
183 struct ceph_inode_info *ci = ceph_inode(inode);
184 struct ceph_file_layout *lo = &ci->i_layout;
185 u32 blockoff;
186 u64 blockno;
187
188 /* Expand the start downward */
189 blockno = div_u64_rem(rreq->start, lo->stripe_unit, &blockoff);
190 rreq->start = blockno * lo->stripe_unit;
191 rreq->len += blockoff;
192
193 /* Now, round up the length to the next block */
194 rreq->len = roundup(rreq->len, lo->stripe_unit);
195}
196
197static bool ceph_netfs_clamp_length(struct netfs_read_subrequest *subreq)
198{
199 struct inode *inode = subreq->rreq->mapping->host;
200 struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
201 struct ceph_inode_info *ci = ceph_inode(inode);
202 u64 objno, objoff;
203 u32 xlen;
204
205 /* Truncate the extent at the end of the current block */
206 ceph_calc_file_object_mapping(&ci->i_layout, subreq->start, subreq->len,
207 &objno, &objoff, &xlen);
208 subreq->len = min(xlen, fsc->mount_options->rsize);
209 return true;
210}
211
212static void finish_netfs_read(struct ceph_osd_request *req)
213{
214 struct ceph_fs_client *fsc = ceph_inode_to_client(req->r_inode);
215 struct ceph_osd_data *osd_data = osd_req_op_extent_osd_data(req, 0);
216 struct netfs_read_subrequest *subreq = req->r_priv;
217 int num_pages;
218 int err = req->r_result;
219
220 ceph_update_read_metrics(&fsc->mdsc->metric, req->r_start_latency,
221 req->r_end_latency, osd_data->length, err);
222
223 dout("%s: result %d subreq->len=%zu i_size=%lld\n", __func__, req->r_result,
224 subreq->len, i_size_read(req->r_inode));
225
226 /* no object means success but no data */
227 if (err == -ENOENT)
228 err = 0;
229 else if (err == -EBLOCKLISTED)
230 fsc->blocklisted = true;
231
232 if (err >= 0 && err < subreq->len)
233 __set_bit(NETFS_SREQ_CLEAR_TAIL, &subreq->flags);
234
235 netfs_subreq_terminated(subreq, err, true);
236
237 num_pages = calc_pages_for(osd_data->alignment, osd_data->length);
238 ceph_put_page_vector(osd_data->pages, num_pages, false);
239 iput(req->r_inode);
240}
241
242static void ceph_netfs_issue_op(struct netfs_read_subrequest *subreq)
243{
244 struct netfs_read_request *rreq = subreq->rreq;
245 struct inode *inode = rreq->mapping->host;
246 struct ceph_inode_info *ci = ceph_inode(inode);
247 struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
248 struct ceph_osd_request *req;
249 struct ceph_vino vino = ceph_vino(inode);
250 struct iov_iter iter;
251 struct page **pages;
252 size_t page_off;
253 int err = 0;
254 u64 len = subreq->len;
255
256 req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout, vino, subreq->start, &len,
257 0, 1, CEPH_OSD_OP_READ,
258 CEPH_OSD_FLAG_READ | fsc->client->osdc.client->options->read_from_replica,
259 NULL, ci->i_truncate_seq, ci->i_truncate_size, false);
260 if (IS_ERR(req)) {
261 err = PTR_ERR(req);
262 req = NULL;
263 goto out;
264 }
265
266 dout("%s: pos=%llu orig_len=%zu len=%llu\n", __func__, subreq->start, subreq->len, len);
267 iov_iter_xarray(&iter, READ, &rreq->mapping->i_pages, subreq->start, len);
268 err = iov_iter_get_pages_alloc(&iter, &pages, len, &page_off);
269 if (err < 0) {
270 dout("%s: iov_ter_get_pages_alloc returned %d\n", __func__, err);
271 goto out;
272 }
273
274 /* should always give us a page-aligned read */
275 WARN_ON_ONCE(page_off);
276 len = err;
277
278 osd_req_op_extent_osd_data_pages(req, 0, pages, len, 0, false, false);
279 req->r_callback = finish_netfs_read;
280 req->r_priv = subreq;
281 req->r_inode = inode;
282 ihold(inode);
283
284 err = ceph_osdc_start_request(req->r_osdc, req, false);
285 if (err)
286 iput(inode);
287out:
288 ceph_osdc_put_request(req);
289 if (err)
290 netfs_subreq_terminated(subreq, err, false);
291 dout("%s: result %d\n", __func__, err);
292}
293
294static void ceph_init_rreq(struct netfs_read_request *rreq, struct file *file)
295{
296}
297
298static void ceph_readahead_cleanup(struct address_space *mapping, void *priv)
299{
300 struct inode *inode = mapping->host;
301 struct ceph_inode_info *ci = ceph_inode(inode);
302 int got = (uintptr_t)priv;
303
304 if (got)
305 ceph_put_cap_refs(ci, got);
306}
307
308static const struct netfs_read_request_ops ceph_netfs_read_ops = {
309 .init_rreq = ceph_init_rreq,
310 .is_cache_enabled = ceph_is_cache_enabled,
311 .begin_cache_operation = ceph_begin_cache_operation,
312 .issue_op = ceph_netfs_issue_op,
313 .expand_readahead = ceph_netfs_expand_readahead,
314 .clamp_length = ceph_netfs_clamp_length,
315 .check_write_begin = ceph_netfs_check_write_begin,
316 .cleanup = ceph_readahead_cleanup,
317};
318
319/* read a single page, without unlocking it. */
320static int ceph_readpage(struct file *file, struct page *page)
321{
322 struct inode *inode = file_inode(file);
323 struct ceph_inode_info *ci = ceph_inode(inode);
324 struct ceph_vino vino = ceph_vino(inode);
325 u64 off = page_offset(page);
326 u64 len = thp_size(page);
327
328 if (ci->i_inline_version != CEPH_INLINE_NONE) {
329 /*
330 * Uptodate inline data should have been added
331 * into page cache while getting Fcr caps.
332 */
333 if (off == 0) {
334 unlock_page(page);
335 return -EINVAL;
336 }
337 zero_user_segment(page, 0, thp_size(page));
338 SetPageUptodate(page);
339 unlock_page(page);
340 return 0;
341 }
342
343 dout("readpage ino %llx.%llx file %p off %llu len %llu page %p index %lu\n",
344 vino.ino, vino.snap, file, off, len, page, page->index);
345
346 return netfs_readpage(file, page, &ceph_netfs_read_ops, NULL);
347}
348
349static void ceph_readahead(struct readahead_control *ractl)
350{
351 struct inode *inode = file_inode(ractl->file);
352 struct ceph_file_info *fi = ractl->file->private_data;
353 struct ceph_rw_context *rw_ctx;
354 int got = 0;
355 int ret = 0;
356
357 if (ceph_inode(inode)->i_inline_version != CEPH_INLINE_NONE)
358 return;
359
360 rw_ctx = ceph_find_rw_context(fi);
361 if (!rw_ctx) {
362 /*
363 * readahead callers do not necessarily hold Fcb caps
364 * (e.g. fadvise, madvise).
365 */
366 int want = CEPH_CAP_FILE_CACHE;
367
368 ret = ceph_try_get_caps(inode, CEPH_CAP_FILE_RD, want, true, &got);
369 if (ret < 0)
370 dout("start_read %p, error getting cap\n", inode);
371 else if (!(got & want))
372 dout("start_read %p, no cache cap\n", inode);
373
374 if (ret <= 0)
375 return;
376 }
377 netfs_readahead(ractl, &ceph_netfs_read_ops, (void *)(uintptr_t)got);
378}
379
380struct ceph_writeback_ctl
381{
382 loff_t i_size;
383 u64 truncate_size;
384 u32 truncate_seq;
385 bool size_stable;
386 bool head_snapc;
387};
388
389/*
390 * Get ref for the oldest snapc for an inode with dirty data... that is, the
391 * only snap context we are allowed to write back.
392 */
393static struct ceph_snap_context *
394get_oldest_context(struct inode *inode, struct ceph_writeback_ctl *ctl,
395 struct ceph_snap_context *page_snapc)
396{
397 struct ceph_inode_info *ci = ceph_inode(inode);
398 struct ceph_snap_context *snapc = NULL;
399 struct ceph_cap_snap *capsnap = NULL;
400
401 spin_lock(&ci->i_ceph_lock);
402 list_for_each_entry(capsnap, &ci->i_cap_snaps, ci_item) {
403 dout(" cap_snap %p snapc %p has %d dirty pages\n", capsnap,
404 capsnap->context, capsnap->dirty_pages);
405 if (!capsnap->dirty_pages)
406 continue;
407
408 /* get i_size, truncate_{seq,size} for page_snapc? */
409 if (snapc && capsnap->context != page_snapc)
410 continue;
411
412 if (ctl) {
413 if (capsnap->writing) {
414 ctl->i_size = i_size_read(inode);
415 ctl->size_stable = false;
416 } else {
417 ctl->i_size = capsnap->size;
418 ctl->size_stable = true;
419 }
420 ctl->truncate_size = capsnap->truncate_size;
421 ctl->truncate_seq = capsnap->truncate_seq;
422 ctl->head_snapc = false;
423 }
424
425 if (snapc)
426 break;
427
428 snapc = ceph_get_snap_context(capsnap->context);
429 if (!page_snapc ||
430 page_snapc == snapc ||
431 page_snapc->seq > snapc->seq)
432 break;
433 }
434 if (!snapc && ci->i_wrbuffer_ref_head) {
435 snapc = ceph_get_snap_context(ci->i_head_snapc);
436 dout(" head snapc %p has %d dirty pages\n",
437 snapc, ci->i_wrbuffer_ref_head);
438 if (ctl) {
439 ctl->i_size = i_size_read(inode);
440 ctl->truncate_size = ci->i_truncate_size;
441 ctl->truncate_seq = ci->i_truncate_seq;
442 ctl->size_stable = false;
443 ctl->head_snapc = true;
444 }
445 }
446 spin_unlock(&ci->i_ceph_lock);
447 return snapc;
448}
449
450static u64 get_writepages_data_length(struct inode *inode,
451 struct page *page, u64 start)
452{
453 struct ceph_inode_info *ci = ceph_inode(inode);
454 struct ceph_snap_context *snapc = page_snap_context(page);
455 struct ceph_cap_snap *capsnap = NULL;
456 u64 end = i_size_read(inode);
457
458 if (snapc != ci->i_head_snapc) {
459 bool found = false;
460 spin_lock(&ci->i_ceph_lock);
461 list_for_each_entry(capsnap, &ci->i_cap_snaps, ci_item) {
462 if (capsnap->context == snapc) {
463 if (!capsnap->writing)
464 end = capsnap->size;
465 found = true;
466 break;
467 }
468 }
469 spin_unlock(&ci->i_ceph_lock);
470 WARN_ON(!found);
471 }
472 if (end > page_offset(page) + thp_size(page))
473 end = page_offset(page) + thp_size(page);
474 return end > start ? end - start : 0;
475}
476
477/*
478 * Write a single page, but leave the page locked.
479 *
480 * If we get a write error, mark the mapping for error, but still adjust the
481 * dirty page accounting (i.e., page is no longer dirty).
482 */
483static int writepage_nounlock(struct page *page, struct writeback_control *wbc)
484{
485 struct inode *inode = page->mapping->host;
486 struct ceph_inode_info *ci = ceph_inode(inode);
487 struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
488 struct ceph_snap_context *snapc, *oldest;
489 loff_t page_off = page_offset(page);
490 int err;
491 loff_t len = thp_size(page);
492 struct ceph_writeback_ctl ceph_wbc;
493 struct ceph_osd_client *osdc = &fsc->client->osdc;
494 struct ceph_osd_request *req;
495
496 dout("writepage %p idx %lu\n", page, page->index);
497
498 /* verify this is a writeable snap context */
499 snapc = page_snap_context(page);
500 if (!snapc) {
501 dout("writepage %p page %p not dirty?\n", inode, page);
502 return 0;
503 }
504 oldest = get_oldest_context(inode, &ceph_wbc, snapc);
505 if (snapc->seq > oldest->seq) {
506 dout("writepage %p page %p snapc %p not writeable - noop\n",
507 inode, page, snapc);
508 /* we should only noop if called by kswapd */
509 WARN_ON(!(current->flags & PF_MEMALLOC));
510 ceph_put_snap_context(oldest);
511 redirty_page_for_writepage(wbc, page);
512 return 0;
513 }
514 ceph_put_snap_context(oldest);
515
516 /* is this a partial page at end of file? */
517 if (page_off >= ceph_wbc.i_size) {
518 dout("%p page eof %llu\n", page, ceph_wbc.i_size);
519 page->mapping->a_ops->invalidatepage(page, 0, thp_size(page));
520 return 0;
521 }
522
523 if (ceph_wbc.i_size < page_off + len)
524 len = ceph_wbc.i_size - page_off;
525
526 dout("writepage %p page %p index %lu on %llu~%llu snapc %p seq %lld\n",
527 inode, page, page->index, page_off, len, snapc, snapc->seq);
528
529 if (atomic_long_inc_return(&fsc->writeback_count) >
530 CONGESTION_ON_THRESH(fsc->mount_options->congestion_kb))
531 set_bdi_congested(inode_to_bdi(inode), BLK_RW_ASYNC);
532
533 set_page_writeback(page);
534 req = ceph_osdc_new_request(osdc, &ci->i_layout, ceph_vino(inode), page_off, &len, 0, 1,
535 CEPH_OSD_OP_WRITE, CEPH_OSD_FLAG_WRITE, snapc,
536 ceph_wbc.truncate_seq, ceph_wbc.truncate_size,
537 true);
538 if (IS_ERR(req)) {
539 redirty_page_for_writepage(wbc, page);
540 end_page_writeback(page);
541 return PTR_ERR(req);
542 }
543
544 /* it may be a short write due to an object boundary */
545 WARN_ON_ONCE(len > thp_size(page));
546 osd_req_op_extent_osd_data_pages(req, 0, &page, len, 0, false, false);
547 dout("writepage %llu~%llu (%llu bytes)\n", page_off, len, len);
548
549 req->r_mtime = inode->i_mtime;
550 err = ceph_osdc_start_request(osdc, req, true);
551 if (!err)
552 err = ceph_osdc_wait_request(osdc, req);
553
554 ceph_update_write_metrics(&fsc->mdsc->metric, req->r_start_latency,
555 req->r_end_latency, len, err);
556
557 ceph_osdc_put_request(req);
558 if (err == 0)
559 err = len;
560
561 if (err < 0) {
562 struct writeback_control tmp_wbc;
563 if (!wbc)
564 wbc = &tmp_wbc;
565 if (err == -ERESTARTSYS) {
566 /* killed by SIGKILL */
567 dout("writepage interrupted page %p\n", page);
568 redirty_page_for_writepage(wbc, page);
569 end_page_writeback(page);
570 return err;
571 }
572 if (err == -EBLOCKLISTED)
573 fsc->blocklisted = true;
574 dout("writepage setting page/mapping error %d %p\n",
575 err, page);
576 mapping_set_error(&inode->i_data, err);
577 wbc->pages_skipped++;
578 } else {
579 dout("writepage cleaned page %p\n", page);
580 err = 0; /* vfs expects us to return 0 */
581 }
582 oldest = detach_page_private(page);
583 WARN_ON_ONCE(oldest != snapc);
584 end_page_writeback(page);
585 ceph_put_wrbuffer_cap_refs(ci, 1, snapc);
586 ceph_put_snap_context(snapc); /* page's reference */
587
588 if (atomic_long_dec_return(&fsc->writeback_count) <
589 CONGESTION_OFF_THRESH(fsc->mount_options->congestion_kb))
590 clear_bdi_congested(inode_to_bdi(inode), BLK_RW_ASYNC);
591
592 return err;
593}
594
595static int ceph_writepage(struct page *page, struct writeback_control *wbc)
596{
597 int err;
598 struct inode *inode = page->mapping->host;
599 BUG_ON(!inode);
600 ihold(inode);
601 err = writepage_nounlock(page, wbc);
602 if (err == -ERESTARTSYS) {
603 /* direct memory reclaimer was killed by SIGKILL. return 0
604 * to prevent caller from setting mapping/page error */
605 err = 0;
606 }
607 unlock_page(page);
608 iput(inode);
609 return err;
610}
611
612/*
613 * async writeback completion handler.
614 *
615 * If we get an error, set the mapping error bit, but not the individual
616 * page error bits.
617 */
618static void writepages_finish(struct ceph_osd_request *req)
619{
620 struct inode *inode = req->r_inode;
621 struct ceph_inode_info *ci = ceph_inode(inode);
622 struct ceph_osd_data *osd_data;
623 struct page *page;
624 int num_pages, total_pages = 0;
625 int i, j;
626 int rc = req->r_result;
627 struct ceph_snap_context *snapc = req->r_snapc;
628 struct address_space *mapping = inode->i_mapping;
629 struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
630 unsigned int len = 0;
631 bool remove_page;
632
633 dout("writepages_finish %p rc %d\n", inode, rc);
634 if (rc < 0) {
635 mapping_set_error(mapping, rc);
636 ceph_set_error_write(ci);
637 if (rc == -EBLOCKLISTED)
638 fsc->blocklisted = true;
639 } else {
640 ceph_clear_error_write(ci);
641 }
642
643 /*
644 * We lost the cache cap, need to truncate the page before
645 * it is unlocked, otherwise we'd truncate it later in the
646 * page truncation thread, possibly losing some data that
647 * raced its way in
648 */
649 remove_page = !(ceph_caps_issued(ci) &
650 (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO));
651
652 /* clean all pages */
653 for (i = 0; i < req->r_num_ops; i++) {
654 if (req->r_ops[i].op != CEPH_OSD_OP_WRITE)
655 break;
656
657 osd_data = osd_req_op_extent_osd_data(req, i);
658 BUG_ON(osd_data->type != CEPH_OSD_DATA_TYPE_PAGES);
659 len += osd_data->length;
660 num_pages = calc_pages_for((u64)osd_data->alignment,
661 (u64)osd_data->length);
662 total_pages += num_pages;
663 for (j = 0; j < num_pages; j++) {
664 page = osd_data->pages[j];
665 BUG_ON(!page);
666 WARN_ON(!PageUptodate(page));
667
668 if (atomic_long_dec_return(&fsc->writeback_count) <
669 CONGESTION_OFF_THRESH(
670 fsc->mount_options->congestion_kb))
671 clear_bdi_congested(inode_to_bdi(inode),
672 BLK_RW_ASYNC);
673
674 ceph_put_snap_context(detach_page_private(page));
675 end_page_writeback(page);
676 dout("unlocking %p\n", page);
677
678 if (remove_page)
679 generic_error_remove_page(inode->i_mapping,
680 page);
681
682 unlock_page(page);
683 }
684 dout("writepages_finish %p wrote %llu bytes cleaned %d pages\n",
685 inode, osd_data->length, rc >= 0 ? num_pages : 0);
686
687 release_pages(osd_data->pages, num_pages);
688 }
689
690 ceph_update_write_metrics(&fsc->mdsc->metric, req->r_start_latency,
691 req->r_end_latency, len, rc);
692
693 ceph_put_wrbuffer_cap_refs(ci, total_pages, snapc);
694
695 osd_data = osd_req_op_extent_osd_data(req, 0);
696 if (osd_data->pages_from_pool)
697 mempool_free(osd_data->pages, ceph_wb_pagevec_pool);
698 else
699 kfree(osd_data->pages);
700 ceph_osdc_put_request(req);
701}
702
703/*
704 * initiate async writeback
705 */
706static int ceph_writepages_start(struct address_space *mapping,
707 struct writeback_control *wbc)
708{
709 struct inode *inode = mapping->host;
710 struct ceph_inode_info *ci = ceph_inode(inode);
711 struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
712 struct ceph_vino vino = ceph_vino(inode);
713 pgoff_t index, start_index, end = -1;
714 struct ceph_snap_context *snapc = NULL, *last_snapc = NULL, *pgsnapc;
715 struct pagevec pvec;
716 int rc = 0;
717 unsigned int wsize = i_blocksize(inode);
718 struct ceph_osd_request *req = NULL;
719 struct ceph_writeback_ctl ceph_wbc;
720 bool should_loop, range_whole = false;
721 bool done = false;
722
723 dout("writepages_start %p (mode=%s)\n", inode,
724 wbc->sync_mode == WB_SYNC_NONE ? "NONE" :
725 (wbc->sync_mode == WB_SYNC_ALL ? "ALL" : "HOLD"));
726
727 if (READ_ONCE(fsc->mount_state) >= CEPH_MOUNT_SHUTDOWN) {
728 if (ci->i_wrbuffer_ref > 0) {
729 pr_warn_ratelimited(
730 "writepage_start %p %lld forced umount\n",
731 inode, ceph_ino(inode));
732 }
733 mapping_set_error(mapping, -EIO);
734 return -EIO; /* we're in a forced umount, don't write! */
735 }
736 if (fsc->mount_options->wsize < wsize)
737 wsize = fsc->mount_options->wsize;
738
739 pagevec_init(&pvec);
740
741 start_index = wbc->range_cyclic ? mapping->writeback_index : 0;
742 index = start_index;
743
744retry:
745 /* find oldest snap context with dirty data */
746 snapc = get_oldest_context(inode, &ceph_wbc, NULL);
747 if (!snapc) {
748 /* hmm, why does writepages get called when there
749 is no dirty data? */
750 dout(" no snap context with dirty data?\n");
751 goto out;
752 }
753 dout(" oldest snapc is %p seq %lld (%d snaps)\n",
754 snapc, snapc->seq, snapc->num_snaps);
755
756 should_loop = false;
757 if (ceph_wbc.head_snapc && snapc != last_snapc) {
758 /* where to start/end? */
759 if (wbc->range_cyclic) {
760 index = start_index;
761 end = -1;
762 if (index > 0)
763 should_loop = true;
764 dout(" cyclic, start at %lu\n", index);
765 } else {
766 index = wbc->range_start >> PAGE_SHIFT;
767 end = wbc->range_end >> PAGE_SHIFT;
768 if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX)
769 range_whole = true;
770 dout(" not cyclic, %lu to %lu\n", index, end);
771 }
772 } else if (!ceph_wbc.head_snapc) {
773 /* Do not respect wbc->range_{start,end}. Dirty pages
774 * in that range can be associated with newer snapc.
775 * They are not writeable until we write all dirty pages
776 * associated with 'snapc' get written */
777 if (index > 0)
778 should_loop = true;
779 dout(" non-head snapc, range whole\n");
780 }
781
782 ceph_put_snap_context(last_snapc);
783 last_snapc = snapc;
784
785 while (!done && index <= end) {
786 int num_ops = 0, op_idx;
787 unsigned i, pvec_pages, max_pages, locked_pages = 0;
788 struct page **pages = NULL, **data_pages;
789 struct page *page;
790 pgoff_t strip_unit_end = 0;
791 u64 offset = 0, len = 0;
792 bool from_pool = false;
793
794 max_pages = wsize >> PAGE_SHIFT;
795
796get_more_pages:
797 pvec_pages = pagevec_lookup_range_tag(&pvec, mapping, &index,
798 end, PAGECACHE_TAG_DIRTY);
799 dout("pagevec_lookup_range_tag got %d\n", pvec_pages);
800 if (!pvec_pages && !locked_pages)
801 break;
802 for (i = 0; i < pvec_pages && locked_pages < max_pages; i++) {
803 page = pvec.pages[i];
804 dout("? %p idx %lu\n", page, page->index);
805 if (locked_pages == 0)
806 lock_page(page); /* first page */
807 else if (!trylock_page(page))
808 break;
809
810 /* only dirty pages, or our accounting breaks */
811 if (unlikely(!PageDirty(page)) ||
812 unlikely(page->mapping != mapping)) {
813 dout("!dirty or !mapping %p\n", page);
814 unlock_page(page);
815 continue;
816 }
817 /* only if matching snap context */
818 pgsnapc = page_snap_context(page);
819 if (pgsnapc != snapc) {
820 dout("page snapc %p %lld != oldest %p %lld\n",
821 pgsnapc, pgsnapc->seq, snapc, snapc->seq);
822 if (!should_loop &&
823 !ceph_wbc.head_snapc &&
824 wbc->sync_mode != WB_SYNC_NONE)
825 should_loop = true;
826 unlock_page(page);
827 continue;
828 }
829 if (page_offset(page) >= ceph_wbc.i_size) {
830 dout("%p page eof %llu\n",
831 page, ceph_wbc.i_size);
832 if ((ceph_wbc.size_stable ||
833 page_offset(page) >= i_size_read(inode)) &&
834 clear_page_dirty_for_io(page))
835 mapping->a_ops->invalidatepage(page,
836 0, thp_size(page));
837 unlock_page(page);
838 continue;
839 }
840 if (strip_unit_end && (page->index > strip_unit_end)) {
841 dout("end of strip unit %p\n", page);
842 unlock_page(page);
843 break;
844 }
845 if (PageWriteback(page)) {
846 if (wbc->sync_mode == WB_SYNC_NONE) {
847 dout("%p under writeback\n", page);
848 unlock_page(page);
849 continue;
850 }
851 dout("waiting on writeback %p\n", page);
852 wait_on_page_writeback(page);
853 }
854
855 if (!clear_page_dirty_for_io(page)) {
856 dout("%p !clear_page_dirty_for_io\n", page);
857 unlock_page(page);
858 continue;
859 }
860
861 /*
862 * We have something to write. If this is
863 * the first locked page this time through,
864 * calculate max possinle write size and
865 * allocate a page array
866 */
867 if (locked_pages == 0) {
868 u64 objnum;
869 u64 objoff;
870 u32 xlen;
871
872 /* prepare async write request */
873 offset = (u64)page_offset(page);
874 ceph_calc_file_object_mapping(&ci->i_layout,
875 offset, wsize,
876 &objnum, &objoff,
877 &xlen);
878 len = xlen;
879
880 num_ops = 1;
881 strip_unit_end = page->index +
882 ((len - 1) >> PAGE_SHIFT);
883
884 BUG_ON(pages);
885 max_pages = calc_pages_for(0, (u64)len);
886 pages = kmalloc_array(max_pages,
887 sizeof(*pages),
888 GFP_NOFS);
889 if (!pages) {
890 from_pool = true;
891 pages = mempool_alloc(ceph_wb_pagevec_pool, GFP_NOFS);
892 BUG_ON(!pages);
893 }
894
895 len = 0;
896 } else if (page->index !=
897 (offset + len) >> PAGE_SHIFT) {
898 if (num_ops >= (from_pool ? CEPH_OSD_SLAB_OPS :
899 CEPH_OSD_MAX_OPS)) {
900 redirty_page_for_writepage(wbc, page);
901 unlock_page(page);
902 break;
903 }
904
905 num_ops++;
906 offset = (u64)page_offset(page);
907 len = 0;
908 }
909
910 /* note position of first page in pvec */
911 dout("%p will write page %p idx %lu\n",
912 inode, page, page->index);
913
914 if (atomic_long_inc_return(&fsc->writeback_count) >
915 CONGESTION_ON_THRESH(
916 fsc->mount_options->congestion_kb)) {
917 set_bdi_congested(inode_to_bdi(inode),
918 BLK_RW_ASYNC);
919 }
920
921
922 pages[locked_pages++] = page;
923 pvec.pages[i] = NULL;
924
925 len += thp_size(page);
926 }
927
928 /* did we get anything? */
929 if (!locked_pages)
930 goto release_pvec_pages;
931 if (i) {
932 unsigned j, n = 0;
933 /* shift unused page to beginning of pvec */
934 for (j = 0; j < pvec_pages; j++) {
935 if (!pvec.pages[j])
936 continue;
937 if (n < j)
938 pvec.pages[n] = pvec.pages[j];
939 n++;
940 }
941 pvec.nr = n;
942
943 if (pvec_pages && i == pvec_pages &&
944 locked_pages < max_pages) {
945 dout("reached end pvec, trying for more\n");
946 pagevec_release(&pvec);
947 goto get_more_pages;
948 }
949 }
950
951new_request:
952 offset = page_offset(pages[0]);
953 len = wsize;
954
955 req = ceph_osdc_new_request(&fsc->client->osdc,
956 &ci->i_layout, vino,
957 offset, &len, 0, num_ops,
958 CEPH_OSD_OP_WRITE, CEPH_OSD_FLAG_WRITE,
959 snapc, ceph_wbc.truncate_seq,
960 ceph_wbc.truncate_size, false);
961 if (IS_ERR(req)) {
962 req = ceph_osdc_new_request(&fsc->client->osdc,
963 &ci->i_layout, vino,
964 offset, &len, 0,
965 min(num_ops,
966 CEPH_OSD_SLAB_OPS),
967 CEPH_OSD_OP_WRITE,
968 CEPH_OSD_FLAG_WRITE,
969 snapc, ceph_wbc.truncate_seq,
970 ceph_wbc.truncate_size, true);
971 BUG_ON(IS_ERR(req));
972 }
973 BUG_ON(len < page_offset(pages[locked_pages - 1]) +
974 thp_size(page) - offset);
975
976 req->r_callback = writepages_finish;
977 req->r_inode = inode;
978
979 /* Format the osd request message and submit the write */
980 len = 0;
981 data_pages = pages;
982 op_idx = 0;
983 for (i = 0; i < locked_pages; i++) {
984 u64 cur_offset = page_offset(pages[i]);
985 if (offset + len != cur_offset) {
986 if (op_idx + 1 == req->r_num_ops)
987 break;
988 osd_req_op_extent_dup_last(req, op_idx,
989 cur_offset - offset);
990 dout("writepages got pages at %llu~%llu\n",
991 offset, len);
992 osd_req_op_extent_osd_data_pages(req, op_idx,
993 data_pages, len, 0,
994 from_pool, false);
995 osd_req_op_extent_update(req, op_idx, len);
996
997 len = 0;
998 offset = cur_offset;
999 data_pages = pages + i;
1000 op_idx++;
1001 }
1002
1003 set_page_writeback(pages[i]);
1004 len += thp_size(page);
1005 }
1006
1007 if (ceph_wbc.size_stable) {
1008 len = min(len, ceph_wbc.i_size - offset);
1009 } else if (i == locked_pages) {
1010 /* writepages_finish() clears writeback pages
1011 * according to the data length, so make sure
1012 * data length covers all locked pages */
1013 u64 min_len = len + 1 - thp_size(page);
1014 len = get_writepages_data_length(inode, pages[i - 1],
1015 offset);
1016 len = max(len, min_len);
1017 }
1018 dout("writepages got pages at %llu~%llu\n", offset, len);
1019
1020 osd_req_op_extent_osd_data_pages(req, op_idx, data_pages, len,
1021 0, from_pool, false);
1022 osd_req_op_extent_update(req, op_idx, len);
1023
1024 BUG_ON(op_idx + 1 != req->r_num_ops);
1025
1026 from_pool = false;
1027 if (i < locked_pages) {
1028 BUG_ON(num_ops <= req->r_num_ops);
1029 num_ops -= req->r_num_ops;
1030 locked_pages -= i;
1031
1032 /* allocate new pages array for next request */
1033 data_pages = pages;
1034 pages = kmalloc_array(locked_pages, sizeof(*pages),
1035 GFP_NOFS);
1036 if (!pages) {
1037 from_pool = true;
1038 pages = mempool_alloc(ceph_wb_pagevec_pool, GFP_NOFS);
1039 BUG_ON(!pages);
1040 }
1041 memcpy(pages, data_pages + i,
1042 locked_pages * sizeof(*pages));
1043 memset(data_pages + i, 0,
1044 locked_pages * sizeof(*pages));
1045 } else {
1046 BUG_ON(num_ops != req->r_num_ops);
1047 index = pages[i - 1]->index + 1;
1048 /* request message now owns the pages array */
1049 pages = NULL;
1050 }
1051
1052 req->r_mtime = inode->i_mtime;
1053 rc = ceph_osdc_start_request(&fsc->client->osdc, req, true);
1054 BUG_ON(rc);
1055 req = NULL;
1056
1057 wbc->nr_to_write -= i;
1058 if (pages)
1059 goto new_request;
1060
1061 /*
1062 * We stop writing back only if we are not doing
1063 * integrity sync. In case of integrity sync we have to
1064 * keep going until we have written all the pages
1065 * we tagged for writeback prior to entering this loop.
1066 */
1067 if (wbc->nr_to_write <= 0 && wbc->sync_mode == WB_SYNC_NONE)
1068 done = true;
1069
1070release_pvec_pages:
1071 dout("pagevec_release on %d pages (%p)\n", (int)pvec.nr,
1072 pvec.nr ? pvec.pages[0] : NULL);
1073 pagevec_release(&pvec);
1074 }
1075
1076 if (should_loop && !done) {
1077 /* more to do; loop back to beginning of file */
1078 dout("writepages looping back to beginning of file\n");
1079 end = start_index - 1; /* OK even when start_index == 0 */
1080
1081 /* to write dirty pages associated with next snapc,
1082 * we need to wait until current writes complete */
1083 if (wbc->sync_mode != WB_SYNC_NONE &&
1084 start_index == 0 && /* all dirty pages were checked */
1085 !ceph_wbc.head_snapc) {
1086 struct page *page;
1087 unsigned i, nr;
1088 index = 0;
1089 while ((index <= end) &&
1090 (nr = pagevec_lookup_tag(&pvec, mapping, &index,
1091 PAGECACHE_TAG_WRITEBACK))) {
1092 for (i = 0; i < nr; i++) {
1093 page = pvec.pages[i];
1094 if (page_snap_context(page) != snapc)
1095 continue;
1096 wait_on_page_writeback(page);
1097 }
1098 pagevec_release(&pvec);
1099 cond_resched();
1100 }
1101 }
1102
1103 start_index = 0;
1104 index = 0;
1105 goto retry;
1106 }
1107
1108 if (wbc->range_cyclic || (range_whole && wbc->nr_to_write > 0))
1109 mapping->writeback_index = index;
1110
1111out:
1112 ceph_osdc_put_request(req);
1113 ceph_put_snap_context(last_snapc);
1114 dout("writepages dend - startone, rc = %d\n", rc);
1115 return rc;
1116}
1117
1118
1119
1120/*
1121 * See if a given @snapc is either writeable, or already written.
1122 */
1123static int context_is_writeable_or_written(struct inode *inode,
1124 struct ceph_snap_context *snapc)
1125{
1126 struct ceph_snap_context *oldest = get_oldest_context(inode, NULL, NULL);
1127 int ret = !oldest || snapc->seq <= oldest->seq;
1128
1129 ceph_put_snap_context(oldest);
1130 return ret;
1131}
1132
1133/**
1134 * ceph_find_incompatible - find an incompatible context and return it
1135 * @page: page being dirtied
1136 *
1137 * We are only allowed to write into/dirty a page if the page is
1138 * clean, or already dirty within the same snap context. Returns a
1139 * conflicting context if there is one, NULL if there isn't, or a
1140 * negative error code on other errors.
1141 *
1142 * Must be called with page lock held.
1143 */
1144static struct ceph_snap_context *
1145ceph_find_incompatible(struct page *page)
1146{
1147 struct inode *inode = page->mapping->host;
1148 struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
1149 struct ceph_inode_info *ci = ceph_inode(inode);
1150
1151 if (READ_ONCE(fsc->mount_state) >= CEPH_MOUNT_SHUTDOWN) {
1152 dout(" page %p forced umount\n", page);
1153 return ERR_PTR(-EIO);
1154 }
1155
1156 for (;;) {
1157 struct ceph_snap_context *snapc, *oldest;
1158
1159 wait_on_page_writeback(page);
1160
1161 snapc = page_snap_context(page);
1162 if (!snapc || snapc == ci->i_head_snapc)
1163 break;
1164
1165 /*
1166 * this page is already dirty in another (older) snap
1167 * context! is it writeable now?
1168 */
1169 oldest = get_oldest_context(inode, NULL, NULL);
1170 if (snapc->seq > oldest->seq) {
1171 /* not writeable -- return it for the caller to deal with */
1172 ceph_put_snap_context(oldest);
1173 dout(" page %p snapc %p not current or oldest\n", page, snapc);
1174 return ceph_get_snap_context(snapc);
1175 }
1176 ceph_put_snap_context(oldest);
1177
1178 /* yay, writeable, do it now (without dropping page lock) */
1179 dout(" page %p snapc %p not current, but oldest\n", page, snapc);
1180 if (clear_page_dirty_for_io(page)) {
1181 int r = writepage_nounlock(page, NULL);
1182 if (r < 0)
1183 return ERR_PTR(r);
1184 }
1185 }
1186 return NULL;
1187}
1188
1189static int ceph_netfs_check_write_begin(struct file *file, loff_t pos, unsigned int len,
1190 struct page *page, void **_fsdata)
1191{
1192 struct inode *inode = file_inode(file);
1193 struct ceph_inode_info *ci = ceph_inode(inode);
1194 struct ceph_snap_context *snapc;
1195
1196 snapc = ceph_find_incompatible(page);
1197 if (snapc) {
1198 int r;
1199
1200 unlock_page(page);
1201 put_page(page);
1202 if (IS_ERR(snapc))
1203 return PTR_ERR(snapc);
1204
1205 ceph_queue_writeback(inode);
1206 r = wait_event_killable(ci->i_cap_wq,
1207 context_is_writeable_or_written(inode, snapc));
1208 ceph_put_snap_context(snapc);
1209 return r == 0 ? -EAGAIN : r;
1210 }
1211 return 0;
1212}
1213
1214/*
1215 * We are only allowed to write into/dirty the page if the page is
1216 * clean, or already dirty within the same snap context.
1217 */
1218static int ceph_write_begin(struct file *file, struct address_space *mapping,
1219 loff_t pos, unsigned len, unsigned flags,
1220 struct page **pagep, void **fsdata)
1221{
1222 struct inode *inode = file_inode(file);
1223 struct ceph_inode_info *ci = ceph_inode(inode);
1224 struct page *page = NULL;
1225 pgoff_t index = pos >> PAGE_SHIFT;
1226 int r;
1227
1228 /*
1229 * Uninlining should have already been done and everything updated, EXCEPT
1230 * for inline_version sent to the MDS.
1231 */
1232 if (ci->i_inline_version != CEPH_INLINE_NONE) {
1233 page = grab_cache_page_write_begin(mapping, index, flags);
1234 if (!page)
1235 return -ENOMEM;
1236
1237 /*
1238 * The inline_version on a new inode is set to 1. If that's the
1239 * case, then the page is brand new and isn't yet Uptodate.
1240 */
1241 r = 0;
1242 if (index == 0 && ci->i_inline_version != 1) {
1243 if (!PageUptodate(page)) {
1244 WARN_ONCE(1, "ceph: write_begin called on still-inlined inode (inline_version %llu)!\n",
1245 ci->i_inline_version);
1246 r = -EINVAL;
1247 }
1248 goto out;
1249 }
1250 zero_user_segment(page, 0, thp_size(page));
1251 SetPageUptodate(page);
1252 goto out;
1253 }
1254
1255 r = netfs_write_begin(file, inode->i_mapping, pos, len, 0, &page, NULL,
1256 &ceph_netfs_read_ops, NULL);
1257out:
1258 if (r == 0)
1259 wait_on_page_fscache(page);
1260 if (r < 0) {
1261 if (page)
1262 put_page(page);
1263 } else {
1264 WARN_ON_ONCE(!PageLocked(page));
1265 *pagep = page;
1266 }
1267 return r;
1268}
1269
1270/*
1271 * we don't do anything in here that simple_write_end doesn't do
1272 * except adjust dirty page accounting
1273 */
1274static int ceph_write_end(struct file *file, struct address_space *mapping,
1275 loff_t pos, unsigned len, unsigned copied,
1276 struct page *page, void *fsdata)
1277{
1278 struct inode *inode = file_inode(file);
1279 bool check_cap = false;
1280
1281 dout("write_end file %p inode %p page %p %d~%d (%d)\n", file,
1282 inode, page, (int)pos, (int)copied, (int)len);
1283
1284 /* zero the stale part of the page if we did a short copy */
1285 if (!PageUptodate(page)) {
1286 if (copied < len) {
1287 copied = 0;
1288 goto out;
1289 }
1290 SetPageUptodate(page);
1291 }
1292
1293 /* did file size increase? */
1294 if (pos+copied > i_size_read(inode))
1295 check_cap = ceph_inode_set_size(inode, pos+copied);
1296
1297 set_page_dirty(page);
1298
1299out:
1300 unlock_page(page);
1301 put_page(page);
1302
1303 if (check_cap)
1304 ceph_check_caps(ceph_inode(inode), CHECK_CAPS_AUTHONLY, NULL);
1305
1306 return copied;
1307}
1308
1309/*
1310 * we set .direct_IO to indicate direct io is supported, but since we
1311 * intercept O_DIRECT reads and writes early, this function should
1312 * never get called.
1313 */
1314static ssize_t ceph_direct_io(struct kiocb *iocb, struct iov_iter *iter)
1315{
1316 WARN_ON(1);
1317 return -EINVAL;
1318}
1319
1320const struct address_space_operations ceph_aops = {
1321 .readpage = ceph_readpage,
1322 .readahead = ceph_readahead,
1323 .writepage = ceph_writepage,
1324 .writepages = ceph_writepages_start,
1325 .write_begin = ceph_write_begin,
1326 .write_end = ceph_write_end,
1327 .set_page_dirty = ceph_set_page_dirty,
1328 .invalidatepage = ceph_invalidatepage,
1329 .releasepage = ceph_releasepage,
1330 .direct_IO = ceph_direct_io,
1331};
1332
1333static void ceph_block_sigs(sigset_t *oldset)
1334{
1335 sigset_t mask;
1336 siginitsetinv(&mask, sigmask(SIGKILL));
1337 sigprocmask(SIG_BLOCK, &mask, oldset);
1338}
1339
1340static void ceph_restore_sigs(sigset_t *oldset)
1341{
1342 sigprocmask(SIG_SETMASK, oldset, NULL);
1343}
1344
1345/*
1346 * vm ops
1347 */
1348static vm_fault_t ceph_filemap_fault(struct vm_fault *vmf)
1349{
1350 struct vm_area_struct *vma = vmf->vma;
1351 struct inode *inode = file_inode(vma->vm_file);
1352 struct ceph_inode_info *ci = ceph_inode(inode);
1353 struct ceph_file_info *fi = vma->vm_file->private_data;
1354 loff_t off = (loff_t)vmf->pgoff << PAGE_SHIFT;
1355 int want, got, err;
1356 sigset_t oldset;
1357 vm_fault_t ret = VM_FAULT_SIGBUS;
1358
1359 ceph_block_sigs(&oldset);
1360
1361 dout("filemap_fault %p %llx.%llx %llu trying to get caps\n",
1362 inode, ceph_vinop(inode), off);
1363 if (fi->fmode & CEPH_FILE_MODE_LAZY)
1364 want = CEPH_CAP_FILE_CACHE | CEPH_CAP_FILE_LAZYIO;
1365 else
1366 want = CEPH_CAP_FILE_CACHE;
1367
1368 got = 0;
1369 err = ceph_get_caps(vma->vm_file, CEPH_CAP_FILE_RD, want, -1, &got);
1370 if (err < 0)
1371 goto out_restore;
1372
1373 dout("filemap_fault %p %llu got cap refs on %s\n",
1374 inode, off, ceph_cap_string(got));
1375
1376 if ((got & (CEPH_CAP_FILE_CACHE | CEPH_CAP_FILE_LAZYIO)) ||
1377 ci->i_inline_version == CEPH_INLINE_NONE) {
1378 CEPH_DEFINE_RW_CONTEXT(rw_ctx, got);
1379 ceph_add_rw_context(fi, &rw_ctx);
1380 ret = filemap_fault(vmf);
1381 ceph_del_rw_context(fi, &rw_ctx);
1382 dout("filemap_fault %p %llu drop cap refs %s ret %x\n",
1383 inode, off, ceph_cap_string(got), ret);
1384 } else
1385 err = -EAGAIN;
1386
1387 ceph_put_cap_refs(ci, got);
1388
1389 if (err != -EAGAIN)
1390 goto out_restore;
1391
1392 /* read inline data */
1393 if (off >= PAGE_SIZE) {
1394 /* does not support inline data > PAGE_SIZE */
1395 ret = VM_FAULT_SIGBUS;
1396 } else {
1397 struct address_space *mapping = inode->i_mapping;
1398 struct page *page = find_or_create_page(mapping, 0,
1399 mapping_gfp_constraint(mapping,
1400 ~__GFP_FS));
1401 if (!page) {
1402 ret = VM_FAULT_OOM;
1403 goto out_inline;
1404 }
1405 err = __ceph_do_getattr(inode, page,
1406 CEPH_STAT_CAP_INLINE_DATA, true);
1407 if (err < 0 || off >= i_size_read(inode)) {
1408 unlock_page(page);
1409 put_page(page);
1410 ret = vmf_error(err);
1411 goto out_inline;
1412 }
1413 if (err < PAGE_SIZE)
1414 zero_user_segment(page, err, PAGE_SIZE);
1415 else
1416 flush_dcache_page(page);
1417 SetPageUptodate(page);
1418 vmf->page = page;
1419 ret = VM_FAULT_MAJOR | VM_FAULT_LOCKED;
1420out_inline:
1421 dout("filemap_fault %p %llu read inline data ret %x\n",
1422 inode, off, ret);
1423 }
1424out_restore:
1425 ceph_restore_sigs(&oldset);
1426 if (err < 0)
1427 ret = vmf_error(err);
1428
1429 return ret;
1430}
1431
1432static vm_fault_t ceph_page_mkwrite(struct vm_fault *vmf)
1433{
1434 struct vm_area_struct *vma = vmf->vma;
1435 struct inode *inode = file_inode(vma->vm_file);
1436 struct ceph_inode_info *ci = ceph_inode(inode);
1437 struct ceph_file_info *fi = vma->vm_file->private_data;
1438 struct ceph_cap_flush *prealloc_cf;
1439 struct page *page = vmf->page;
1440 loff_t off = page_offset(page);
1441 loff_t size = i_size_read(inode);
1442 size_t len;
1443 int want, got, err;
1444 sigset_t oldset;
1445 vm_fault_t ret = VM_FAULT_SIGBUS;
1446
1447 prealloc_cf = ceph_alloc_cap_flush();
1448 if (!prealloc_cf)
1449 return VM_FAULT_OOM;
1450
1451 sb_start_pagefault(inode->i_sb);
1452 ceph_block_sigs(&oldset);
1453
1454 if (ci->i_inline_version != CEPH_INLINE_NONE) {
1455 struct page *locked_page = NULL;
1456 if (off == 0) {
1457 lock_page(page);
1458 locked_page = page;
1459 }
1460 err = ceph_uninline_data(vma->vm_file, locked_page);
1461 if (locked_page)
1462 unlock_page(locked_page);
1463 if (err < 0)
1464 goto out_free;
1465 }
1466
1467 if (off + thp_size(page) <= size)
1468 len = thp_size(page);
1469 else
1470 len = offset_in_thp(page, size);
1471
1472 dout("page_mkwrite %p %llx.%llx %llu~%zd getting caps i_size %llu\n",
1473 inode, ceph_vinop(inode), off, len, size);
1474 if (fi->fmode & CEPH_FILE_MODE_LAZY)
1475 want = CEPH_CAP_FILE_BUFFER | CEPH_CAP_FILE_LAZYIO;
1476 else
1477 want = CEPH_CAP_FILE_BUFFER;
1478
1479 got = 0;
1480 err = ceph_get_caps(vma->vm_file, CEPH_CAP_FILE_WR, want, off + len, &got);
1481 if (err < 0)
1482 goto out_free;
1483
1484 dout("page_mkwrite %p %llu~%zd got cap refs on %s\n",
1485 inode, off, len, ceph_cap_string(got));
1486
1487 /* Update time before taking page lock */
1488 file_update_time(vma->vm_file);
1489 inode_inc_iversion_raw(inode);
1490
1491 do {
1492 struct ceph_snap_context *snapc;
1493
1494 lock_page(page);
1495
1496 if (page_mkwrite_check_truncate(page, inode) < 0) {
1497 unlock_page(page);
1498 ret = VM_FAULT_NOPAGE;
1499 break;
1500 }
1501
1502 snapc = ceph_find_incompatible(page);
1503 if (!snapc) {
1504 /* success. we'll keep the page locked. */
1505 set_page_dirty(page);
1506 ret = VM_FAULT_LOCKED;
1507 break;
1508 }
1509
1510 unlock_page(page);
1511
1512 if (IS_ERR(snapc)) {
1513 ret = VM_FAULT_SIGBUS;
1514 break;
1515 }
1516
1517 ceph_queue_writeback(inode);
1518 err = wait_event_killable(ci->i_cap_wq,
1519 context_is_writeable_or_written(inode, snapc));
1520 ceph_put_snap_context(snapc);
1521 } while (err == 0);
1522
1523 if (ret == VM_FAULT_LOCKED ||
1524 ci->i_inline_version != CEPH_INLINE_NONE) {
1525 int dirty;
1526 spin_lock(&ci->i_ceph_lock);
1527 ci->i_inline_version = CEPH_INLINE_NONE;
1528 dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_FILE_WR,
1529 &prealloc_cf);
1530 spin_unlock(&ci->i_ceph_lock);
1531 if (dirty)
1532 __mark_inode_dirty(inode, dirty);
1533 }
1534
1535 dout("page_mkwrite %p %llu~%zd dropping cap refs on %s ret %x\n",
1536 inode, off, len, ceph_cap_string(got), ret);
1537 ceph_put_cap_refs_async(ci, got);
1538out_free:
1539 ceph_restore_sigs(&oldset);
1540 sb_end_pagefault(inode->i_sb);
1541 ceph_free_cap_flush(prealloc_cf);
1542 if (err < 0)
1543 ret = vmf_error(err);
1544 return ret;
1545}
1546
1547void ceph_fill_inline_data(struct inode *inode, struct page *locked_page,
1548 char *data, size_t len)
1549{
1550 struct address_space *mapping = inode->i_mapping;
1551 struct page *page;
1552
1553 if (locked_page) {
1554 page = locked_page;
1555 } else {
1556 if (i_size_read(inode) == 0)
1557 return;
1558 page = find_or_create_page(mapping, 0,
1559 mapping_gfp_constraint(mapping,
1560 ~__GFP_FS));
1561 if (!page)
1562 return;
1563 if (PageUptodate(page)) {
1564 unlock_page(page);
1565 put_page(page);
1566 return;
1567 }
1568 }
1569
1570 dout("fill_inline_data %p %llx.%llx len %zu locked_page %p\n",
1571 inode, ceph_vinop(inode), len, locked_page);
1572
1573 if (len > 0) {
1574 void *kaddr = kmap_atomic(page);
1575 memcpy(kaddr, data, len);
1576 kunmap_atomic(kaddr);
1577 }
1578
1579 if (page != locked_page) {
1580 if (len < PAGE_SIZE)
1581 zero_user_segment(page, len, PAGE_SIZE);
1582 else
1583 flush_dcache_page(page);
1584
1585 SetPageUptodate(page);
1586 unlock_page(page);
1587 put_page(page);
1588 }
1589}
1590
1591int ceph_uninline_data(struct file *filp, struct page *locked_page)
1592{
1593 struct inode *inode = file_inode(filp);
1594 struct ceph_inode_info *ci = ceph_inode(inode);
1595 struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
1596 struct ceph_osd_request *req;
1597 struct page *page = NULL;
1598 u64 len, inline_version;
1599 int err = 0;
1600 bool from_pagecache = false;
1601
1602 spin_lock(&ci->i_ceph_lock);
1603 inline_version = ci->i_inline_version;
1604 spin_unlock(&ci->i_ceph_lock);
1605
1606 dout("uninline_data %p %llx.%llx inline_version %llu\n",
1607 inode, ceph_vinop(inode), inline_version);
1608
1609 if (inline_version == 1 || /* initial version, no data */
1610 inline_version == CEPH_INLINE_NONE)
1611 goto out;
1612
1613 if (locked_page) {
1614 page = locked_page;
1615 WARN_ON(!PageUptodate(page));
1616 } else if (ceph_caps_issued(ci) &
1617 (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)) {
1618 page = find_get_page(inode->i_mapping, 0);
1619 if (page) {
1620 if (PageUptodate(page)) {
1621 from_pagecache = true;
1622 lock_page(page);
1623 } else {
1624 put_page(page);
1625 page = NULL;
1626 }
1627 }
1628 }
1629
1630 if (page) {
1631 len = i_size_read(inode);
1632 if (len > PAGE_SIZE)
1633 len = PAGE_SIZE;
1634 } else {
1635 page = __page_cache_alloc(GFP_NOFS);
1636 if (!page) {
1637 err = -ENOMEM;
1638 goto out;
1639 }
1640 err = __ceph_do_getattr(inode, page,
1641 CEPH_STAT_CAP_INLINE_DATA, true);
1642 if (err < 0) {
1643 /* no inline data */
1644 if (err == -ENODATA)
1645 err = 0;
1646 goto out;
1647 }
1648 len = err;
1649 }
1650
1651 req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout,
1652 ceph_vino(inode), 0, &len, 0, 1,
1653 CEPH_OSD_OP_CREATE, CEPH_OSD_FLAG_WRITE,
1654 NULL, 0, 0, false);
1655 if (IS_ERR(req)) {
1656 err = PTR_ERR(req);
1657 goto out;
1658 }
1659
1660 req->r_mtime = inode->i_mtime;
1661 err = ceph_osdc_start_request(&fsc->client->osdc, req, false);
1662 if (!err)
1663 err = ceph_osdc_wait_request(&fsc->client->osdc, req);
1664 ceph_osdc_put_request(req);
1665 if (err < 0)
1666 goto out;
1667
1668 req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout,
1669 ceph_vino(inode), 0, &len, 1, 3,
1670 CEPH_OSD_OP_WRITE, CEPH_OSD_FLAG_WRITE,
1671 NULL, ci->i_truncate_seq,
1672 ci->i_truncate_size, false);
1673 if (IS_ERR(req)) {
1674 err = PTR_ERR(req);
1675 goto out;
1676 }
1677
1678 osd_req_op_extent_osd_data_pages(req, 1, &page, len, 0, false, false);
1679
1680 {
1681 __le64 xattr_buf = cpu_to_le64(inline_version);
1682 err = osd_req_op_xattr_init(req, 0, CEPH_OSD_OP_CMPXATTR,
1683 "inline_version", &xattr_buf,
1684 sizeof(xattr_buf),
1685 CEPH_OSD_CMPXATTR_OP_GT,
1686 CEPH_OSD_CMPXATTR_MODE_U64);
1687 if (err)
1688 goto out_put;
1689 }
1690
1691 {
1692 char xattr_buf[32];
1693 int xattr_len = snprintf(xattr_buf, sizeof(xattr_buf),
1694 "%llu", inline_version);
1695 err = osd_req_op_xattr_init(req, 2, CEPH_OSD_OP_SETXATTR,
1696 "inline_version",
1697 xattr_buf, xattr_len, 0, 0);
1698 if (err)
1699 goto out_put;
1700 }
1701
1702 req->r_mtime = inode->i_mtime;
1703 err = ceph_osdc_start_request(&fsc->client->osdc, req, false);
1704 if (!err)
1705 err = ceph_osdc_wait_request(&fsc->client->osdc, req);
1706
1707 ceph_update_write_metrics(&fsc->mdsc->metric, req->r_start_latency,
1708 req->r_end_latency, len, err);
1709
1710out_put:
1711 ceph_osdc_put_request(req);
1712 if (err == -ECANCELED)
1713 err = 0;
1714out:
1715 if (page && page != locked_page) {
1716 if (from_pagecache) {
1717 unlock_page(page);
1718 put_page(page);
1719 } else
1720 __free_pages(page, 0);
1721 }
1722
1723 dout("uninline_data %p %llx.%llx inline_version %llu = %d\n",
1724 inode, ceph_vinop(inode), inline_version, err);
1725 return err;
1726}
1727
1728static const struct vm_operations_struct ceph_vmops = {
1729 .fault = ceph_filemap_fault,
1730 .page_mkwrite = ceph_page_mkwrite,
1731};
1732
1733int ceph_mmap(struct file *file, struct vm_area_struct *vma)
1734{
1735 struct address_space *mapping = file->f_mapping;
1736
1737 if (!mapping->a_ops->readpage)
1738 return -ENOEXEC;
1739 file_accessed(file);
1740 vma->vm_ops = &ceph_vmops;
1741 return 0;
1742}
1743
1744enum {
1745 POOL_READ = 1,
1746 POOL_WRITE = 2,
1747};
1748
1749static int __ceph_pool_perm_get(struct ceph_inode_info *ci,
1750 s64 pool, struct ceph_string *pool_ns)
1751{
1752 struct ceph_fs_client *fsc = ceph_inode_to_client(&ci->vfs_inode);
1753 struct ceph_mds_client *mdsc = fsc->mdsc;
1754 struct ceph_osd_request *rd_req = NULL, *wr_req = NULL;
1755 struct rb_node **p, *parent;
1756 struct ceph_pool_perm *perm;
1757 struct page **pages;
1758 size_t pool_ns_len;
1759 int err = 0, err2 = 0, have = 0;
1760
1761 down_read(&mdsc->pool_perm_rwsem);
1762 p = &mdsc->pool_perm_tree.rb_node;
1763 while (*p) {
1764 perm = rb_entry(*p, struct ceph_pool_perm, node);
1765 if (pool < perm->pool)
1766 p = &(*p)->rb_left;
1767 else if (pool > perm->pool)
1768 p = &(*p)->rb_right;
1769 else {
1770 int ret = ceph_compare_string(pool_ns,
1771 perm->pool_ns,
1772 perm->pool_ns_len);
1773 if (ret < 0)
1774 p = &(*p)->rb_left;
1775 else if (ret > 0)
1776 p = &(*p)->rb_right;
1777 else {
1778 have = perm->perm;
1779 break;
1780 }
1781 }
1782 }
1783 up_read(&mdsc->pool_perm_rwsem);
1784 if (*p)
1785 goto out;
1786
1787 if (pool_ns)
1788 dout("__ceph_pool_perm_get pool %lld ns %.*s no perm cached\n",
1789 pool, (int)pool_ns->len, pool_ns->str);
1790 else
1791 dout("__ceph_pool_perm_get pool %lld no perm cached\n", pool);
1792
1793 down_write(&mdsc->pool_perm_rwsem);
1794 p = &mdsc->pool_perm_tree.rb_node;
1795 parent = NULL;
1796 while (*p) {
1797 parent = *p;
1798 perm = rb_entry(parent, struct ceph_pool_perm, node);
1799 if (pool < perm->pool)
1800 p = &(*p)->rb_left;
1801 else if (pool > perm->pool)
1802 p = &(*p)->rb_right;
1803 else {
1804 int ret = ceph_compare_string(pool_ns,
1805 perm->pool_ns,
1806 perm->pool_ns_len);
1807 if (ret < 0)
1808 p = &(*p)->rb_left;
1809 else if (ret > 0)
1810 p = &(*p)->rb_right;
1811 else {
1812 have = perm->perm;
1813 break;
1814 }
1815 }
1816 }
1817 if (*p) {
1818 up_write(&mdsc->pool_perm_rwsem);
1819 goto out;
1820 }
1821
1822 rd_req = ceph_osdc_alloc_request(&fsc->client->osdc, NULL,
1823 1, false, GFP_NOFS);
1824 if (!rd_req) {
1825 err = -ENOMEM;
1826 goto out_unlock;
1827 }
1828
1829 rd_req->r_flags = CEPH_OSD_FLAG_READ;
1830 osd_req_op_init(rd_req, 0, CEPH_OSD_OP_STAT, 0);
1831 rd_req->r_base_oloc.pool = pool;
1832 if (pool_ns)
1833 rd_req->r_base_oloc.pool_ns = ceph_get_string(pool_ns);
1834 ceph_oid_printf(&rd_req->r_base_oid, "%llx.00000000", ci->i_vino.ino);
1835
1836 err = ceph_osdc_alloc_messages(rd_req, GFP_NOFS);
1837 if (err)
1838 goto out_unlock;
1839
1840 wr_req = ceph_osdc_alloc_request(&fsc->client->osdc, NULL,
1841 1, false, GFP_NOFS);
1842 if (!wr_req) {
1843 err = -ENOMEM;
1844 goto out_unlock;
1845 }
1846
1847 wr_req->r_flags = CEPH_OSD_FLAG_WRITE;
1848 osd_req_op_init(wr_req, 0, CEPH_OSD_OP_CREATE, CEPH_OSD_OP_FLAG_EXCL);
1849 ceph_oloc_copy(&wr_req->r_base_oloc, &rd_req->r_base_oloc);
1850 ceph_oid_copy(&wr_req->r_base_oid, &rd_req->r_base_oid);
1851
1852 err = ceph_osdc_alloc_messages(wr_req, GFP_NOFS);
1853 if (err)
1854 goto out_unlock;
1855
1856 /* one page should be large enough for STAT data */
1857 pages = ceph_alloc_page_vector(1, GFP_KERNEL);
1858 if (IS_ERR(pages)) {
1859 err = PTR_ERR(pages);
1860 goto out_unlock;
1861 }
1862
1863 osd_req_op_raw_data_in_pages(rd_req, 0, pages, PAGE_SIZE,
1864 0, false, true);
1865 err = ceph_osdc_start_request(&fsc->client->osdc, rd_req, false);
1866
1867 wr_req->r_mtime = ci->vfs_inode.i_mtime;
1868 err2 = ceph_osdc_start_request(&fsc->client->osdc, wr_req, false);
1869
1870 if (!err)
1871 err = ceph_osdc_wait_request(&fsc->client->osdc, rd_req);
1872 if (!err2)
1873 err2 = ceph_osdc_wait_request(&fsc->client->osdc, wr_req);
1874
1875 if (err >= 0 || err == -ENOENT)
1876 have |= POOL_READ;
1877 else if (err != -EPERM) {
1878 if (err == -EBLOCKLISTED)
1879 fsc->blocklisted = true;
1880 goto out_unlock;
1881 }
1882
1883 if (err2 == 0 || err2 == -EEXIST)
1884 have |= POOL_WRITE;
1885 else if (err2 != -EPERM) {
1886 if (err2 == -EBLOCKLISTED)
1887 fsc->blocklisted = true;
1888 err = err2;
1889 goto out_unlock;
1890 }
1891
1892 pool_ns_len = pool_ns ? pool_ns->len : 0;
1893 perm = kmalloc(sizeof(*perm) + pool_ns_len + 1, GFP_NOFS);
1894 if (!perm) {
1895 err = -ENOMEM;
1896 goto out_unlock;
1897 }
1898
1899 perm->pool = pool;
1900 perm->perm = have;
1901 perm->pool_ns_len = pool_ns_len;
1902 if (pool_ns_len > 0)
1903 memcpy(perm->pool_ns, pool_ns->str, pool_ns_len);
1904 perm->pool_ns[pool_ns_len] = 0;
1905
1906 rb_link_node(&perm->node, parent, p);
1907 rb_insert_color(&perm->node, &mdsc->pool_perm_tree);
1908 err = 0;
1909out_unlock:
1910 up_write(&mdsc->pool_perm_rwsem);
1911
1912 ceph_osdc_put_request(rd_req);
1913 ceph_osdc_put_request(wr_req);
1914out:
1915 if (!err)
1916 err = have;
1917 if (pool_ns)
1918 dout("__ceph_pool_perm_get pool %lld ns %.*s result = %d\n",
1919 pool, (int)pool_ns->len, pool_ns->str, err);
1920 else
1921 dout("__ceph_pool_perm_get pool %lld result = %d\n", pool, err);
1922 return err;
1923}
1924
1925int ceph_pool_perm_check(struct inode *inode, int need)
1926{
1927 struct ceph_inode_info *ci = ceph_inode(inode);
1928 struct ceph_string *pool_ns;
1929 s64 pool;
1930 int ret, flags;
1931
1932 /* Only need to do this for regular files */
1933 if (!S_ISREG(inode->i_mode))
1934 return 0;
1935
1936 if (ci->i_vino.snap != CEPH_NOSNAP) {
1937 /*
1938 * Pool permission check needs to write to the first object.
1939 * But for snapshot, head of the first object may have alread
1940 * been deleted. Skip check to avoid creating orphan object.
1941 */
1942 return 0;
1943 }
1944
1945 if (ceph_test_mount_opt(ceph_inode_to_client(inode),
1946 NOPOOLPERM))
1947 return 0;
1948
1949 spin_lock(&ci->i_ceph_lock);
1950 flags = ci->i_ceph_flags;
1951 pool = ci->i_layout.pool_id;
1952 spin_unlock(&ci->i_ceph_lock);
1953check:
1954 if (flags & CEPH_I_POOL_PERM) {
1955 if ((need & CEPH_CAP_FILE_RD) && !(flags & CEPH_I_POOL_RD)) {
1956 dout("ceph_pool_perm_check pool %lld no read perm\n",
1957 pool);
1958 return -EPERM;
1959 }
1960 if ((need & CEPH_CAP_FILE_WR) && !(flags & CEPH_I_POOL_WR)) {
1961 dout("ceph_pool_perm_check pool %lld no write perm\n",
1962 pool);
1963 return -EPERM;
1964 }
1965 return 0;
1966 }
1967
1968 pool_ns = ceph_try_get_string(ci->i_layout.pool_ns);
1969 ret = __ceph_pool_perm_get(ci, pool, pool_ns);
1970 ceph_put_string(pool_ns);
1971 if (ret < 0)
1972 return ret;
1973
1974 flags = CEPH_I_POOL_PERM;
1975 if (ret & POOL_READ)
1976 flags |= CEPH_I_POOL_RD;
1977 if (ret & POOL_WRITE)
1978 flags |= CEPH_I_POOL_WR;
1979
1980 spin_lock(&ci->i_ceph_lock);
1981 if (pool == ci->i_layout.pool_id &&
1982 pool_ns == rcu_dereference_raw(ci->i_layout.pool_ns)) {
1983 ci->i_ceph_flags |= flags;
1984 } else {
1985 pool = ci->i_layout.pool_id;
1986 flags = ci->i_ceph_flags;
1987 }
1988 spin_unlock(&ci->i_ceph_lock);
1989 goto check;
1990}
1991
1992void ceph_pool_perm_destroy(struct ceph_mds_client *mdsc)
1993{
1994 struct ceph_pool_perm *perm;
1995 struct rb_node *n;
1996
1997 while (!RB_EMPTY_ROOT(&mdsc->pool_perm_tree)) {
1998 n = rb_first(&mdsc->pool_perm_tree);
1999 perm = rb_entry(n, struct ceph_pool_perm, node);
2000 rb_erase(n, &mdsc->pool_perm_tree);
2001 kfree(perm);
2002 }
2003}