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Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/evalenti/linux...
[linux/fpc-iii.git] / fs / ceph / addr.c
blob4801571f51cb4e7461d8d1f9f8f3136fb6713fbc
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 "cache.h"
15 #include <linux/ceph/osd_client.h>
16
17 /*
18 * Ceph address space ops.
19 *
20 * There are a few funny things going on here.
21 *
22 * The page->private field is used to reference a struct
23 * ceph_snap_context for _every_ dirty page. This indicates which
24 * snapshot the page was logically dirtied in, and thus which snap
25 * context needs to be associated with the osd write during writeback.
26 *
27 * Similarly, struct ceph_inode_info maintains a set of counters to
28 * count dirty pages on the inode. In the absence of snapshots,
29 * i_wrbuffer_ref == i_wrbuffer_ref_head == the dirty page count.
30 *
31 * When a snapshot is taken (that is, when the client receives
32 * notification that a snapshot was taken), each inode with caps and
33 * with dirty pages (dirty pages implies there is a cap) gets a new
34 * ceph_cap_snap in the i_cap_snaps list (which is sorted in ascending
35 * order, new snaps go to the tail). The i_wrbuffer_ref_head count is
36 * moved to capsnap->dirty. (Unless a sync write is currently in
37 * progress. In that case, the capsnap is said to be "pending", new
38 * writes cannot start, and the capsnap isn't "finalized" until the
39 * write completes (or fails) and a final size/mtime for the inode for
40 * that snap can be settled upon.) i_wrbuffer_ref_head is reset to 0.
41 *
42 * On writeback, we must submit writes to the osd IN SNAP ORDER. So,
43 * we look for the first capsnap in i_cap_snaps and write out pages in
44 * that snap context _only_. Then we move on to the next capsnap,
45 * eventually reaching the "live" or "head" context (i.e., pages that
46 * are not yet snapped) and are writing the most recently dirtied
47 * pages.
48 *
49 * Invalidate and so forth must take care to ensure the dirty page
50 * accounting is preserved.
51 */
52
53 #define CONGESTION_ON_THRESH(congestion_kb) (congestion_kb >> (PAGE_SHIFT-10))
54 #define CONGESTION_OFF_THRESH(congestion_kb) \
55 (CONGESTION_ON_THRESH(congestion_kb) - \
56 (CONGESTION_ON_THRESH(congestion_kb) >> 2))
57
58 static inline struct ceph_snap_context *page_snap_context(struct page *page)
59 {
60 if (PagePrivate(page))
61 return (void *)page->private;
62 return NULL;
63 }
64
65 /*
66 * Dirty a page. Optimistically adjust accounting, on the assumption
67 * that we won't race with invalidate. If we do, readjust.
68 */
69 static int ceph_set_page_dirty(struct page *page)
70 {
71 struct address_space *mapping = page->mapping;
72 struct inode *inode;
73 struct ceph_inode_info *ci;
74 struct ceph_snap_context *snapc;
75 int ret;
76
77 if (unlikely(!mapping))
78 return !TestSetPageDirty(page);
79
80 if (PageDirty(page)) {
81 dout("%p set_page_dirty %p idx %lu -- already dirty\n",
82 mapping->host, page, page->index);
83 BUG_ON(!PagePrivate(page));
84 return 0;
85 }
86
87 inode = mapping->host;
88 ci = ceph_inode(inode);
89
90 /* dirty the head */
91 spin_lock(&ci->i_ceph_lock);
92 BUG_ON(ci->i_wr_ref == 0); // caller should hold Fw reference
93 if (__ceph_have_pending_cap_snap(ci)) {
94 struct ceph_cap_snap *capsnap =
95 list_last_entry(&ci->i_cap_snaps,
96 struct ceph_cap_snap,
97 ci_item);
98 snapc = ceph_get_snap_context(capsnap->context);
99 capsnap->dirty_pages++;
100 } else {
101 BUG_ON(!ci->i_head_snapc);
102 snapc = ceph_get_snap_context(ci->i_head_snapc);
103 ++ci->i_wrbuffer_ref_head;
104 }
105 if (ci->i_wrbuffer_ref == 0)
106 ihold(inode);
107 ++ci->i_wrbuffer_ref;
108 dout("%p set_page_dirty %p idx %lu head %d/%d -> %d/%d "
109 "snapc %p seq %lld (%d snaps)\n",
110 mapping->host, page, page->index,
111 ci->i_wrbuffer_ref-1, ci->i_wrbuffer_ref_head-1,
112 ci->i_wrbuffer_ref, ci->i_wrbuffer_ref_head,
113 snapc, snapc->seq, snapc->num_snaps);
114 spin_unlock(&ci->i_ceph_lock);
115
116 /*
117 * Reference snap context in page->private. Also set
118 * PagePrivate so that we get invalidatepage callback.
119 */
120 BUG_ON(PagePrivate(page));
121 page->private = (unsigned long)snapc;
122 SetPagePrivate(page);
123
124 ret = __set_page_dirty_nobuffers(page);
125 WARN_ON(!PageLocked(page));
126 WARN_ON(!page->mapping);
127
128 return ret;
129 }
130
131 /*
132 * If we are truncating the full page (i.e. offset == 0), adjust the
133 * dirty page counters appropriately. Only called if there is private
134 * data on the page.
135 */
136 static void ceph_invalidatepage(struct page *page, unsigned int offset,
137 unsigned int length)
138 {
139 struct inode *inode;
140 struct ceph_inode_info *ci;
141 struct ceph_snap_context *snapc = page_snap_context(page);
142
143 inode = page->mapping->host;
144 ci = ceph_inode(inode);
145
146 if (offset != 0 || length != PAGE_SIZE) {
147 dout("%p invalidatepage %p idx %lu partial dirty page %u~%u\n",
148 inode, page, page->index, offset, length);
149 return;
150 }
151
152 ceph_invalidate_fscache_page(inode, page);
153
154 if (!PagePrivate(page))
155 return;
156
157 /*
158 * We can get non-dirty pages here due to races between
159 * set_page_dirty and truncate_complete_page; just spit out a
160 * warning, in case we end up with accounting problems later.
161 */
162 if (!PageDirty(page))
163 pr_err("%p invalidatepage %p page not dirty\n", inode, page);
164
165 ClearPageChecked(page);
166
167 dout("%p invalidatepage %p idx %lu full dirty page\n",
168 inode, page, page->index);
169
170 ceph_put_wrbuffer_cap_refs(ci, 1, snapc);
171 ceph_put_snap_context(snapc);
172 page->private = 0;
173 ClearPagePrivate(page);
174 }
175
176 static int ceph_releasepage(struct page *page, gfp_t g)
177 {
178 dout("%p releasepage %p idx %lu\n", page->mapping->host,
179 page, page->index);
180 WARN_ON(PageDirty(page));
181
182 /* Can we release the page from the cache? */
183 if (!ceph_release_fscache_page(page, g))
184 return 0;
185
186 return !PagePrivate(page);
187 }
188
189 /*
190 * read a single page, without unlocking it.
191 */
192 static int readpage_nounlock(struct file *filp, struct page *page)
193 {
194 struct inode *inode = file_inode(filp);
195 struct ceph_inode_info *ci = ceph_inode(inode);
196 struct ceph_osd_client *osdc =
197 &ceph_inode_to_client(inode)->client->osdc;
198 int err = 0;
199 u64 off = page_offset(page);
200 u64 len = PAGE_SIZE;
201
202 if (off >= i_size_read(inode)) {
203 zero_user_segment(page, 0, PAGE_SIZE);
204 SetPageUptodate(page);
205 return 0;
206 }
207
208 if (ci->i_inline_version != CEPH_INLINE_NONE) {
209 /*
210 * Uptodate inline data should have been added
211 * into page cache while getting Fcr caps.
212 */
213 if (off == 0)
214 return -EINVAL;
215 zero_user_segment(page, 0, PAGE_SIZE);
216 SetPageUptodate(page);
217 return 0;
218 }
219
220 err = ceph_readpage_from_fscache(inode, page);
221 if (err == 0)
222 goto out;
223
224 dout("readpage inode %p file %p page %p index %lu\n",
225 inode, filp, page, page->index);
226 err = ceph_osdc_readpages(osdc, ceph_vino(inode), &ci->i_layout,
227 off, &len,
228 ci->i_truncate_seq, ci->i_truncate_size,
229 &page, 1, 0);
230 if (err == -ENOENT)
231 err = 0;
232 if (err < 0) {
233 SetPageError(page);
234 ceph_fscache_readpage_cancel(inode, page);
235 goto out;
236 }
237 if (err < PAGE_SIZE)
238 /* zero fill remainder of page */
239 zero_user_segment(page, err, PAGE_SIZE);
240 else
241 flush_dcache_page(page);
242
243 SetPageUptodate(page);
244 ceph_readpage_to_fscache(inode, page);
245
246 out:
247 return err < 0 ? err : 0;
248 }
249
250 static int ceph_readpage(struct file *filp, struct page *page)
251 {
252 int r = readpage_nounlock(filp, page);
253 unlock_page(page);
254 return r;
255 }
256
257 /*
258 * Finish an async read(ahead) op.
259 */
260 static void finish_read(struct ceph_osd_request *req, struct ceph_msg *msg)
261 {
262 struct inode *inode = req->r_inode;
263 struct ceph_osd_data *osd_data;
264 int rc = req->r_result;
265 int bytes = le32_to_cpu(msg->hdr.data_len);
266 int num_pages;
267 int i;
268
269 dout("finish_read %p req %p rc %d bytes %d\n", inode, req, rc, bytes);
270
271 /* unlock all pages, zeroing any data we didn't read */
272 osd_data = osd_req_op_extent_osd_data(req, 0);
273 BUG_ON(osd_data->type != CEPH_OSD_DATA_TYPE_PAGES);
274 num_pages = calc_pages_for((u64)osd_data->alignment,
275 (u64)osd_data->length);
276 for (i = 0; i < num_pages; i++) {
277 struct page *page = osd_data->pages[i];
278
279 if (rc < 0 && rc != -ENOENT)
280 goto unlock;
281 if (bytes < (int)PAGE_SIZE) {
282 /* zero (remainder of) page */
283 int s = bytes < 0 ? 0 : bytes;
284 zero_user_segment(page, s, PAGE_SIZE);
285 }
286 dout("finish_read %p uptodate %p idx %lu\n", inode, page,
287 page->index);
288 flush_dcache_page(page);
289 SetPageUptodate(page);
290 ceph_readpage_to_fscache(inode, page);
291 unlock:
292 unlock_page(page);
293 put_page(page);
294 bytes -= PAGE_SIZE;
295 }
296 kfree(osd_data->pages);
297 }
298
299 static void ceph_unlock_page_vector(struct page **pages, int num_pages)
300 {
301 int i;
302
303 for (i = 0; i < num_pages; i++)
304 unlock_page(pages[i]);
305 }
306
307 /*
308 * start an async read(ahead) operation. return nr_pages we submitted
309 * a read for on success, or negative error code.
310 */
311 static int start_read(struct inode *inode, struct list_head *page_list, int max)
312 {
313 struct ceph_osd_client *osdc =
314 &ceph_inode_to_client(inode)->client->osdc;
315 struct ceph_inode_info *ci = ceph_inode(inode);
316 struct page *page = list_entry(page_list->prev, struct page, lru);
317 struct ceph_vino vino;
318 struct ceph_osd_request *req;
319 u64 off;
320 u64 len;
321 int i;
322 struct page **pages;
323 pgoff_t next_index;
324 int nr_pages = 0;
325 int ret;
326
327 off = (u64) page_offset(page);
328
329 /* count pages */
330 next_index = page->index;
331 list_for_each_entry_reverse(page, page_list, lru) {
332 if (page->index != next_index)
333 break;
334 nr_pages++;
335 next_index++;
336 if (max && nr_pages == max)
337 break;
338 }
339 len = nr_pages << PAGE_SHIFT;
340 dout("start_read %p nr_pages %d is %lld~%lld\n", inode, nr_pages,
341 off, len);
342 vino = ceph_vino(inode);
343 req = ceph_osdc_new_request(osdc, &ci->i_layout, vino, off, &len,
344 0, 1, CEPH_OSD_OP_READ,
345 CEPH_OSD_FLAG_READ, NULL,
346 ci->i_truncate_seq, ci->i_truncate_size,
347 false);
348 if (IS_ERR(req))
349 return PTR_ERR(req);
350
351 /* build page vector */
352 nr_pages = calc_pages_for(0, len);
353 pages = kmalloc(sizeof(*pages) * nr_pages, GFP_KERNEL);
354 ret = -ENOMEM;
355 if (!pages)
356 goto out;
357 for (i = 0; i < nr_pages; ++i) {
358 page = list_entry(page_list->prev, struct page, lru);
359 BUG_ON(PageLocked(page));
360 list_del(&page->lru);
361
362 dout("start_read %p adding %p idx %lu\n", inode, page,
363 page->index);
364 if (add_to_page_cache_lru(page, &inode->i_data, page->index,
365 GFP_KERNEL)) {
366 ceph_fscache_uncache_page(inode, page);
367 put_page(page);
368 dout("start_read %p add_to_page_cache failed %p\n",
369 inode, page);
370 nr_pages = i;
371 goto out_pages;
372 }
373 pages[i] = page;
374 }
375 osd_req_op_extent_osd_data_pages(req, 0, pages, len, 0, false, false);
376 req->r_callback = finish_read;
377 req->r_inode = inode;
378
379 ceph_osdc_build_request(req, off, NULL, vino.snap, NULL);
380
381 dout("start_read %p starting %p %lld~%lld\n", inode, req, off, len);
382 ret = ceph_osdc_start_request(osdc, req, false);
383 if (ret < 0)
384 goto out_pages;
385 ceph_osdc_put_request(req);
386 return nr_pages;
387
388 out_pages:
389 ceph_unlock_page_vector(pages, nr_pages);
390 ceph_release_page_vector(pages, nr_pages);
391 out:
392 ceph_osdc_put_request(req);
393 return ret;
394 }
395
396
397 /*
398 * Read multiple pages. Leave pages we don't read + unlock in page_list;
399 * the caller (VM) cleans them up.
400 */
401 static int ceph_readpages(struct file *file, struct address_space *mapping,
402 struct list_head *page_list, unsigned nr_pages)
403 {
404 struct inode *inode = file_inode(file);
405 struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
406 int rc = 0;
407 int max = 0;
408
409 if (ceph_inode(inode)->i_inline_version != CEPH_INLINE_NONE)
410 return -EINVAL;
411
412 rc = ceph_readpages_from_fscache(mapping->host, mapping, page_list,
413 &nr_pages);
414
415 if (rc == 0)
416 goto out;
417
418 if (fsc->mount_options->rsize >= PAGE_SIZE)
419 max = (fsc->mount_options->rsize + PAGE_SIZE - 1)
420 >> PAGE_SHIFT;
421
422 dout("readpages %p file %p nr_pages %d max %d\n", inode,
423 file, nr_pages,
424 max);
425 while (!list_empty(page_list)) {
426 rc = start_read(inode, page_list, max);
427 if (rc < 0)
428 goto out;
429 BUG_ON(rc == 0);
430 }
431 out:
432 ceph_fscache_readpages_cancel(inode, page_list);
433
434 dout("readpages %p file %p ret %d\n", inode, file, rc);
435 return rc;
436 }
437
438 /*
439 * Get ref for the oldest snapc for an inode with dirty data... that is, the
440 * only snap context we are allowed to write back.
441 */
442 static struct ceph_snap_context *get_oldest_context(struct inode *inode,
443 loff_t *snap_size)
444 {
445 struct ceph_inode_info *ci = ceph_inode(inode);
446 struct ceph_snap_context *snapc = NULL;
447 struct ceph_cap_snap *capsnap = NULL;
448
449 spin_lock(&ci->i_ceph_lock);
450 list_for_each_entry(capsnap, &ci->i_cap_snaps, ci_item) {
451 dout(" cap_snap %p snapc %p has %d dirty pages\n", capsnap,
452 capsnap->context, capsnap->dirty_pages);
453 if (capsnap->dirty_pages) {
454 snapc = ceph_get_snap_context(capsnap->context);
455 if (snap_size)
456 *snap_size = capsnap->size;
457 break;
458 }
459 }
460 if (!snapc && ci->i_wrbuffer_ref_head) {
461 snapc = ceph_get_snap_context(ci->i_head_snapc);
462 dout(" head snapc %p has %d dirty pages\n",
463 snapc, ci->i_wrbuffer_ref_head);
464 }
465 spin_unlock(&ci->i_ceph_lock);
466 return snapc;
467 }
468
469 /*
470 * Write a single page, but leave the page locked.
471 *
472 * If we get a write error, set the page error bit, but still adjust the
473 * dirty page accounting (i.e., page is no longer dirty).
474 */
475 static int writepage_nounlock(struct page *page, struct writeback_control *wbc)
476 {
477 struct inode *inode;
478 struct ceph_inode_info *ci;
479 struct ceph_fs_client *fsc;
480 struct ceph_osd_client *osdc;
481 struct ceph_snap_context *snapc, *oldest;
482 loff_t page_off = page_offset(page);
483 loff_t snap_size = -1;
484 long writeback_stat;
485 u64 truncate_size;
486 u32 truncate_seq;
487 int err = 0, len = PAGE_SIZE;
488
489 dout("writepage %p idx %lu\n", page, page->index);
490
491 if (!page->mapping || !page->mapping->host) {
492 dout("writepage %p - no mapping\n", page);
493 return -EFAULT;
494 }
495 inode = page->mapping->host;
496 ci = ceph_inode(inode);
497 fsc = ceph_inode_to_client(inode);
498 osdc = &fsc->client->osdc;
499
500 /* verify this is a writeable snap context */
501 snapc = page_snap_context(page);
502 if (snapc == NULL) {
503 dout("writepage %p page %p not dirty?\n", inode, page);
504 goto out;
505 }
506 oldest = get_oldest_context(inode, &snap_size);
507 if (snapc->seq > oldest->seq) {
508 dout("writepage %p page %p snapc %p not writeable - noop\n",
509 inode, page, snapc);
510 /* we should only noop if called by kswapd */
511 WARN_ON((current->flags & PF_MEMALLOC) == 0);
512 ceph_put_snap_context(oldest);
513 goto out;
514 }
515 ceph_put_snap_context(oldest);
516
517 spin_lock(&ci->i_ceph_lock);
518 truncate_seq = ci->i_truncate_seq;
519 truncate_size = ci->i_truncate_size;
520 if (snap_size == -1)
521 snap_size = i_size_read(inode);
522 spin_unlock(&ci->i_ceph_lock);
523
524 /* is this a partial page at end of file? */
525 if (page_off >= snap_size) {
526 dout("%p page eof %llu\n", page, snap_size);
527 goto out;
528 }
529 if (snap_size < page_off + len)
530 len = snap_size - page_off;
531
532 dout("writepage %p page %p index %lu on %llu~%u snapc %p\n",
533 inode, page, page->index, page_off, len, snapc);
534
535 writeback_stat = atomic_long_inc_return(&fsc->writeback_count);
536 if (writeback_stat >
537 CONGESTION_ON_THRESH(fsc->mount_options->congestion_kb))
538 set_bdi_congested(&fsc->backing_dev_info, BLK_RW_ASYNC);
539
540 ceph_readpage_to_fscache(inode, page);
541
542 set_page_writeback(page);
543 err = ceph_osdc_writepages(osdc, ceph_vino(inode),
544 &ci->i_layout, snapc,
545 page_off, len,
546 truncate_seq, truncate_size,
547 &inode->i_mtime, &page, 1);
548 if (err < 0) {
549 dout("writepage setting page/mapping error %d %p\n", err, page);
550 SetPageError(page);
551 mapping_set_error(&inode->i_data, err);
552 if (wbc)
553 wbc->pages_skipped++;
554 } else {
555 dout("writepage cleaned page %p\n", page);
556 err = 0; /* vfs expects us to return 0 */
557 }
558 page->private = 0;
559 ClearPagePrivate(page);
560 end_page_writeback(page);
561 ceph_put_wrbuffer_cap_refs(ci, 1, snapc);
562 ceph_put_snap_context(snapc); /* page's reference */
563 out:
564 return err;
565 }
566
567 static int ceph_writepage(struct page *page, struct writeback_control *wbc)
568 {
569 int err;
570 struct inode *inode = page->mapping->host;
571 BUG_ON(!inode);
572 ihold(inode);
573 err = writepage_nounlock(page, wbc);
574 unlock_page(page);
575 iput(inode);
576 return err;
577 }
578
579
580 /*
581 * lame release_pages helper. release_pages() isn't exported to
582 * modules.
583 */
584 static void ceph_release_pages(struct page **pages, int num)
585 {
586 struct pagevec pvec;
587 int i;
588
589 pagevec_init(&pvec, 0);
590 for (i = 0; i < num; i++) {
591 if (pagevec_add(&pvec, pages[i]) == 0)
592 pagevec_release(&pvec);
593 }
594 pagevec_release(&pvec);
595 }
596
597 /*
598 * async writeback completion handler.
599 *
600 * If we get an error, set the mapping error bit, but not the individual
601 * page error bits.
602 */
603 static void writepages_finish(struct ceph_osd_request *req,
604 struct ceph_msg *msg)
605 {
606 struct inode *inode = req->r_inode;
607 struct ceph_inode_info *ci = ceph_inode(inode);
608 struct ceph_osd_data *osd_data;
609 struct page *page;
610 int num_pages, total_pages = 0;
611 int i, j;
612 int rc = req->r_result;
613 struct ceph_snap_context *snapc = req->r_snapc;
614 struct address_space *mapping = inode->i_mapping;
615 struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
616 bool remove_page;
617
618
619 dout("writepages_finish %p rc %d\n", inode, rc);
620 if (rc < 0)
621 mapping_set_error(mapping, rc);
622
623 /*
624 * We lost the cache cap, need to truncate the page before
625 * it is unlocked, otherwise we'd truncate it later in the
626 * page truncation thread, possibly losing some data that
627 * raced its way in
628 */
629 remove_page = !(ceph_caps_issued(ci) &
630 (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO));
631
632 /* clean all pages */
633 for (i = 0; i < req->r_num_ops; i++) {
634 if (req->r_ops[i].op != CEPH_OSD_OP_WRITE)
635 break;
636
637 osd_data = osd_req_op_extent_osd_data(req, i);
638 BUG_ON(osd_data->type != CEPH_OSD_DATA_TYPE_PAGES);
639 num_pages = calc_pages_for((u64)osd_data->alignment,
640 (u64)osd_data->length);
641 total_pages += num_pages;
642 for (j = 0; j < num_pages; j++) {
643 page = osd_data->pages[j];
644 BUG_ON(!page);
645 WARN_ON(!PageUptodate(page));
646
647 if (atomic_long_dec_return(&fsc->writeback_count) <
648 CONGESTION_OFF_THRESH(
649 fsc->mount_options->congestion_kb))
650 clear_bdi_congested(&fsc->backing_dev_info,
651 BLK_RW_ASYNC);
652
653 ceph_put_snap_context(page_snap_context(page));
654 page->private = 0;
655 ClearPagePrivate(page);
656 dout("unlocking %p\n", page);
657 end_page_writeback(page);
658
659 if (remove_page)
660 generic_error_remove_page(inode->i_mapping,
661 page);
662
663 unlock_page(page);
664 }
665 dout("writepages_finish %p wrote %llu bytes cleaned %d pages\n",
666 inode, osd_data->length, rc >= 0 ? num_pages : 0);
667
668 ceph_release_pages(osd_data->pages, num_pages);
669 }
670
671 ceph_put_wrbuffer_cap_refs(ci, total_pages, snapc);
672
673 osd_data = osd_req_op_extent_osd_data(req, 0);
674 if (osd_data->pages_from_pool)
675 mempool_free(osd_data->pages,
676 ceph_sb_to_client(inode->i_sb)->wb_pagevec_pool);
677 else
678 kfree(osd_data->pages);
679 ceph_osdc_put_request(req);
680 }
681
682 /*
683 * initiate async writeback
684 */
685 static int ceph_writepages_start(struct address_space *mapping,
686 struct writeback_control *wbc)
687 {
688 struct inode *inode = mapping->host;
689 struct ceph_inode_info *ci = ceph_inode(inode);
690 struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
691 struct ceph_vino vino = ceph_vino(inode);
692 pgoff_t index, start, end;
693 int range_whole = 0;
694 int should_loop = 1;
695 pgoff_t max_pages = 0, max_pages_ever = 0;
696 struct ceph_snap_context *snapc = NULL, *last_snapc = NULL, *pgsnapc;
697 struct pagevec pvec;
698 int done = 0;
699 int rc = 0;
700 unsigned wsize = 1 << inode->i_blkbits;
701 struct ceph_osd_request *req = NULL;
702 int do_sync = 0;
703 loff_t snap_size, i_size;
704 u64 truncate_size;
705 u32 truncate_seq;
706
707 /*
708 * Include a 'sync' in the OSD request if this is a data
709 * integrity write (e.g., O_SYNC write or fsync()), or if our
710 * cap is being revoked.
711 */
712 if ((wbc->sync_mode == WB_SYNC_ALL) ||
713 ceph_caps_revoking(ci, CEPH_CAP_FILE_BUFFER))
714 do_sync = 1;
715 dout("writepages_start %p dosync=%d (mode=%s)\n",
716 inode, do_sync,
717 wbc->sync_mode == WB_SYNC_NONE ? "NONE" :
718 (wbc->sync_mode == WB_SYNC_ALL ? "ALL" : "HOLD"));
719
720 if (ACCESS_ONCE(fsc->mount_state) == CEPH_MOUNT_SHUTDOWN) {
721 pr_warn("writepage_start %p on forced umount\n", inode);
722 truncate_pagecache(inode, 0);
723 mapping_set_error(mapping, -EIO);
724 return -EIO; /* we're in a forced umount, don't write! */
725 }
726 if (fsc->mount_options->wsize && fsc->mount_options->wsize < wsize)
727 wsize = fsc->mount_options->wsize;
728 if (wsize < PAGE_SIZE)
729 wsize = PAGE_SIZE;
730 max_pages_ever = wsize >> PAGE_SHIFT;
731
732 pagevec_init(&pvec, 0);
733
734 /* where to start/end? */
735 if (wbc->range_cyclic) {
736 start = mapping->writeback_index; /* Start from prev offset */
737 end = -1;
738 dout(" cyclic, start at %lu\n", start);
739 } else {
740 start = wbc->range_start >> PAGE_SHIFT;
741 end = wbc->range_end >> PAGE_SHIFT;
742 if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX)
743 range_whole = 1;
744 should_loop = 0;
745 dout(" not cyclic, %lu to %lu\n", start, end);
746 }
747 index = start;
748
749 retry:
750 /* find oldest snap context with dirty data */
751 ceph_put_snap_context(snapc);
752 snap_size = -1;
753 snapc = get_oldest_context(inode, &snap_size);
754 if (!snapc) {
755 /* hmm, why does writepages get called when there
756 is no dirty data? */
757 dout(" no snap context with dirty data?\n");
758 goto out;
759 }
760 dout(" oldest snapc is %p seq %lld (%d snaps)\n",
761 snapc, snapc->seq, snapc->num_snaps);
762
763 spin_lock(&ci->i_ceph_lock);
764 truncate_seq = ci->i_truncate_seq;
765 truncate_size = ci->i_truncate_size;
766 i_size = i_size_read(inode);
767 spin_unlock(&ci->i_ceph_lock);
768
769 if (last_snapc && snapc != last_snapc) {
770 /* if we switched to a newer snapc, restart our scan at the
771 * start of the original file range. */
772 dout(" snapc differs from last pass, restarting at %lu\n",
773 index);
774 index = start;
775 }
776 last_snapc = snapc;
777
778 while (!done && index <= end) {
779 unsigned i;
780 int first;
781 pgoff_t strip_unit_end = 0;
782 int num_ops = 0, op_idx;
783 int pvec_pages, locked_pages = 0;
784 struct page **pages = NULL, **data_pages;
785 mempool_t *pool = NULL; /* Becomes non-null if mempool used */
786 struct page *page;
787 int want;
788 u64 offset = 0, len = 0;
789
790 max_pages = max_pages_ever;
791
792 get_more_pages:
793 first = -1;
794 want = min(end - index,
795 min((pgoff_t)PAGEVEC_SIZE,
796 max_pages - (pgoff_t)locked_pages) - 1)
797 + 1;
798 pvec_pages = pagevec_lookup_tag(&pvec, mapping, &index,
799 PAGECACHE_TAG_DIRTY,
800 want);
801 dout("pagevec_lookup_tag got %d\n", pvec_pages);
802 if (!pvec_pages && !locked_pages)
803 break;
804 for (i = 0; i < pvec_pages && locked_pages < max_pages; i++) {
805 page = pvec.pages[i];
806 dout("? %p idx %lu\n", page, page->index);
807 if (locked_pages == 0)
808 lock_page(page); /* first page */
809 else if (!trylock_page(page))
810 break;
811
812 /* only dirty pages, or our accounting breaks */
813 if (unlikely(!PageDirty(page)) ||
814 unlikely(page->mapping != mapping)) {
815 dout("!dirty or !mapping %p\n", page);
816 unlock_page(page);
817 break;
818 }
819 if (!wbc->range_cyclic && page->index > end) {
820 dout("end of range %p\n", page);
821 done = 1;
822 unlock_page(page);
823 break;
824 }
825 if (strip_unit_end && (page->index > strip_unit_end)) {
826 dout("end of strip unit %p\n", page);
827 unlock_page(page);
828 break;
829 }
830 if (wbc->sync_mode != WB_SYNC_NONE) {
831 dout("waiting on writeback %p\n", page);
832 wait_on_page_writeback(page);
833 }
834 if (page_offset(page) >=
835 (snap_size == -1 ? i_size : snap_size)) {
836 dout("%p page eof %llu\n", page,
837 (snap_size == -1 ? i_size : snap_size));
838 done = 1;
839 unlock_page(page);
840 break;
841 }
842 if (PageWriteback(page)) {
843 dout("%p under writeback\n", page);
844 unlock_page(page);
845 break;
846 }
847
848 /* only if matching snap context */
849 pgsnapc = page_snap_context(page);
850 if (pgsnapc->seq > snapc->seq) {
851 dout("page snapc %p %lld > oldest %p %lld\n",
852 pgsnapc, pgsnapc->seq, snapc, snapc->seq);
853 unlock_page(page);
854 if (!locked_pages)
855 continue; /* keep looking for snap */
856 break;
857 }
858
859 if (!clear_page_dirty_for_io(page)) {
860 dout("%p !clear_page_dirty_for_io\n", page);
861 unlock_page(page);
862 break;
863 }
864
865 /*
866 * We have something to write. If this is
867 * the first locked page this time through,
868 * calculate max possinle write size and
869 * allocate a page array
870 */
871 if (locked_pages == 0) {
872 u64 objnum;
873 u64 objoff;
874
875 /* prepare async write request */
876 offset = (u64)page_offset(page);
877 len = wsize;
878
879 rc = ceph_calc_file_object_mapping(&ci->i_layout,
880 offset, len,
881 &objnum, &objoff,
882 &len);
883 if (rc < 0) {
884 unlock_page(page);
885 break;
886 }
887
888 num_ops = 1 + do_sync;
889 strip_unit_end = page->index +
890 ((len - 1) >> PAGE_SHIFT);
891
892 BUG_ON(pages);
893 max_pages = calc_pages_for(0, (u64)len);
894 pages = kmalloc(max_pages * sizeof (*pages),
895 GFP_NOFS);
896 if (!pages) {
897 pool = fsc->wb_pagevec_pool;
898 pages = mempool_alloc(pool, GFP_NOFS);
899 BUG_ON(!pages);
900 }
901
902 len = 0;
903 } else if (page->index !=
904 (offset + len) >> PAGE_SHIFT) {
905 if (num_ops >= (pool ? CEPH_OSD_SLAB_OPS :
906 CEPH_OSD_MAX_OPS)) {
907 redirty_page_for_writepage(wbc, page);
908 unlock_page(page);
909 break;
910 }
911
912 num_ops++;
913 offset = (u64)page_offset(page);
914 len = 0;
915 }
916
917 /* note position of first page in pvec */
918 if (first < 0)
919 first = i;
920 dout("%p will write page %p idx %lu\n",
921 inode, page, page->index);
922
923 if (atomic_long_inc_return(&fsc->writeback_count) >
924 CONGESTION_ON_THRESH(
925 fsc->mount_options->congestion_kb)) {
926 set_bdi_congested(&fsc->backing_dev_info,
927 BLK_RW_ASYNC);
928 }
929
930 pages[locked_pages] = page;
931 locked_pages++;
932 len += PAGE_SIZE;
933 }
934
935 /* did we get anything? */
936 if (!locked_pages)
937 goto release_pvec_pages;
938 if (i) {
939 int j;
940 BUG_ON(!locked_pages || first < 0);
941
942 if (pvec_pages && i == pvec_pages &&
943 locked_pages < max_pages) {
944 dout("reached end pvec, trying for more\n");
945 pagevec_reinit(&pvec);
946 goto get_more_pages;
947 }
948
949 /* shift unused pages over in the pvec... we
950 * will need to release them below. */
951 for (j = i; j < pvec_pages; j++) {
952 dout(" pvec leftover page %p\n", pvec.pages[j]);
953 pvec.pages[j-i+first] = pvec.pages[j];
954 }
955 pvec.nr -= i-first;
956 }
957
958 new_request:
959 offset = page_offset(pages[0]);
960 len = wsize;
961
962 req = ceph_osdc_new_request(&fsc->client->osdc,
963 &ci->i_layout, vino,
964 offset, &len, 0, num_ops,
965 CEPH_OSD_OP_WRITE,
966 CEPH_OSD_FLAG_WRITE |
967 CEPH_OSD_FLAG_ONDISK,
968 snapc, truncate_seq,
969 truncate_size, false);
970 if (IS_ERR(req)) {
971 req = ceph_osdc_new_request(&fsc->client->osdc,
972 &ci->i_layout, vino,
973 offset, &len, 0,
974 min(num_ops,
975 CEPH_OSD_SLAB_OPS),
976 CEPH_OSD_OP_WRITE,
977 CEPH_OSD_FLAG_WRITE |
978 CEPH_OSD_FLAG_ONDISK,
979 snapc, truncate_seq,
980 truncate_size, true);
981 BUG_ON(IS_ERR(req));
982 }
983 BUG_ON(len < page_offset(pages[locked_pages - 1]) +
984 PAGE_SIZE - offset);
985
986 req->r_callback = writepages_finish;
987 req->r_inode = inode;
988
989 /* Format the osd request message and submit the write */
990 len = 0;
991 data_pages = pages;
992 op_idx = 0;
993 for (i = 0; i < locked_pages; i++) {
994 u64 cur_offset = page_offset(pages[i]);
995 if (offset + len != cur_offset) {
996 if (op_idx + do_sync + 1 == req->r_num_ops)
997 break;
998 osd_req_op_extent_dup_last(req, op_idx,
999 cur_offset - offset);
1000 dout("writepages got pages at %llu~%llu\n",
1001 offset, len);
1002 osd_req_op_extent_osd_data_pages(req, op_idx,
1003 data_pages, len, 0,
1004 !!pool, false);
1005 osd_req_op_extent_update(req, op_idx, len);
1006
1007 len = 0;
1008 offset = cur_offset;
1009 data_pages = pages + i;
1010 op_idx++;
1011 }
1012
1013 set_page_writeback(pages[i]);
1014 len += PAGE_SIZE;
1015 }
1016
1017 if (snap_size != -1) {
1018 len = min(len, snap_size - offset);
1019 } else if (i == locked_pages) {
1020 /* writepages_finish() clears writeback pages
1021 * according to the data length, so make sure
1022 * data length covers all locked pages */
1023 u64 min_len = len + 1 - PAGE_SIZE;
1024 len = min(len, (u64)i_size_read(inode) - offset);
1025 len = max(len, min_len);
1026 }
1027 dout("writepages got pages at %llu~%llu\n", offset, len);
1028
1029 osd_req_op_extent_osd_data_pages(req, op_idx, data_pages, len,
1030 0, !!pool, false);
1031 osd_req_op_extent_update(req, op_idx, len);
1032
1033 if (do_sync) {
1034 op_idx++;
1035 osd_req_op_init(req, op_idx, CEPH_OSD_OP_STARTSYNC, 0);
1036 }
1037 BUG_ON(op_idx + 1 != req->r_num_ops);
1038
1039 pool = NULL;
1040 if (i < locked_pages) {
1041 BUG_ON(num_ops <= req->r_num_ops);
1042 num_ops -= req->r_num_ops;
1043 num_ops += do_sync;
1044 locked_pages -= i;
1045
1046 /* allocate new pages array for next request */
1047 data_pages = pages;
1048 pages = kmalloc(locked_pages * sizeof (*pages),
1049 GFP_NOFS);
1050 if (!pages) {
1051 pool = fsc->wb_pagevec_pool;
1052 pages = mempool_alloc(pool, GFP_NOFS);
1053 BUG_ON(!pages);
1054 }
1055 memcpy(pages, data_pages + i,
1056 locked_pages * sizeof(*pages));
1057 memset(data_pages + i, 0,
1058 locked_pages * sizeof(*pages));
1059 } else {
1060 BUG_ON(num_ops != req->r_num_ops);
1061 index = pages[i - 1]->index + 1;
1062 /* request message now owns the pages array */
1063 pages = NULL;
1064 }
1065
1066 vino = ceph_vino(inode);
1067 ceph_osdc_build_request(req, offset, snapc, vino.snap,
1068 &inode->i_mtime);
1069
1070 rc = ceph_osdc_start_request(&fsc->client->osdc, req, true);
1071 BUG_ON(rc);
1072 req = NULL;
1073
1074 wbc->nr_to_write -= i;
1075 if (pages)
1076 goto new_request;
1077
1078 if (wbc->nr_to_write <= 0)
1079 done = 1;
1080
1081 release_pvec_pages:
1082 dout("pagevec_release on %d pages (%p)\n", (int)pvec.nr,
1083 pvec.nr ? pvec.pages[0] : NULL);
1084 pagevec_release(&pvec);
1085
1086 if (locked_pages && !done)
1087 goto retry;
1088 }
1089
1090 if (should_loop && !done) {
1091 /* more to do; loop back to beginning of file */
1092 dout("writepages looping back to beginning of file\n");
1093 should_loop = 0;
1094 index = 0;
1095 goto retry;
1096 }
1097
1098 if (wbc->range_cyclic || (range_whole && wbc->nr_to_write > 0))
1099 mapping->writeback_index = index;
1100
1101 out:
1102 if (req)
1103 ceph_osdc_put_request(req);
1104 ceph_put_snap_context(snapc);
1105 dout("writepages done, rc = %d\n", rc);
1106 return rc;
1107 }
1108
1109
1110
1111 /*
1112 * See if a given @snapc is either writeable, or already written.
1113 */
1114 static int context_is_writeable_or_written(struct inode *inode,
1115 struct ceph_snap_context *snapc)
1116 {
1117 struct ceph_snap_context *oldest = get_oldest_context(inode, NULL);
1118 int ret = !oldest || snapc->seq <= oldest->seq;
1119
1120 ceph_put_snap_context(oldest);
1121 return ret;
1122 }
1123
1124 /*
1125 * We are only allowed to write into/dirty the page if the page is
1126 * clean, or already dirty within the same snap context.
1127 *
1128 * called with page locked.
1129 * return success with page locked,
1130 * or any failure (incl -EAGAIN) with page unlocked.
1131 */
1132 static int ceph_update_writeable_page(struct file *file,
1133 loff_t pos, unsigned len,
1134 struct page *page)
1135 {
1136 struct inode *inode = file_inode(file);
1137 struct ceph_inode_info *ci = ceph_inode(inode);
1138 loff_t page_off = pos & PAGE_MASK;
1139 int pos_in_page = pos & ~PAGE_MASK;
1140 int end_in_page = pos_in_page + len;
1141 loff_t i_size;
1142 int r;
1143 struct ceph_snap_context *snapc, *oldest;
1144
1145 retry_locked:
1146 /* writepages currently holds page lock, but if we change that later, */
1147 wait_on_page_writeback(page);
1148
1149 snapc = page_snap_context(page);
1150 if (snapc && snapc != ci->i_head_snapc) {
1151 /*
1152 * this page is already dirty in another (older) snap
1153 * context! is it writeable now?
1154 */
1155 oldest = get_oldest_context(inode, NULL);
1156
1157 if (snapc->seq > oldest->seq) {
1158 ceph_put_snap_context(oldest);
1159 dout(" page %p snapc %p not current or oldest\n",
1160 page, snapc);
1161 /*
1162 * queue for writeback, and wait for snapc to
1163 * be writeable or written
1164 */
1165 snapc = ceph_get_snap_context(snapc);
1166 unlock_page(page);
1167 ceph_queue_writeback(inode);
1168 r = wait_event_interruptible(ci->i_cap_wq,
1169 context_is_writeable_or_written(inode, snapc));
1170 ceph_put_snap_context(snapc);
1171 if (r == -ERESTARTSYS)
1172 return r;
1173 return -EAGAIN;
1174 }
1175 ceph_put_snap_context(oldest);
1176
1177 /* yay, writeable, do it now (without dropping page lock) */
1178 dout(" page %p snapc %p not current, but oldest\n",
1179 page, snapc);
1180 if (!clear_page_dirty_for_io(page))
1181 goto retry_locked;
1182 r = writepage_nounlock(page, NULL);
1183 if (r < 0)
1184 goto fail_nosnap;
1185 goto retry_locked;
1186 }
1187
1188 if (PageUptodate(page)) {
1189 dout(" page %p already uptodate\n", page);
1190 return 0;
1191 }
1192
1193 /* full page? */
1194 if (pos_in_page == 0 && len == PAGE_SIZE)
1195 return 0;
1196
1197 /* past end of file? */
1198 i_size = i_size_read(inode);
1199
1200 if (page_off >= i_size ||
1201 (pos_in_page == 0 && (pos+len) >= i_size &&
1202 end_in_page - pos_in_page != PAGE_SIZE)) {
1203 dout(" zeroing %p 0 - %d and %d - %d\n",
1204 page, pos_in_page, end_in_page, (int)PAGE_SIZE);
1205 zero_user_segments(page,
1206 0, pos_in_page,
1207 end_in_page, PAGE_SIZE);
1208 return 0;
1209 }
1210
1211 /* we need to read it. */
1212 r = readpage_nounlock(file, page);
1213 if (r < 0)
1214 goto fail_nosnap;
1215 goto retry_locked;
1216 fail_nosnap:
1217 unlock_page(page);
1218 return r;
1219 }
1220
1221 /*
1222 * We are only allowed to write into/dirty the page if the page is
1223 * clean, or already dirty within the same snap context.
1224 */
1225 static int ceph_write_begin(struct file *file, struct address_space *mapping,
1226 loff_t pos, unsigned len, unsigned flags,
1227 struct page **pagep, void **fsdata)
1228 {
1229 struct inode *inode = file_inode(file);
1230 struct page *page;
1231 pgoff_t index = pos >> PAGE_SHIFT;
1232 int r;
1233
1234 do {
1235 /* get a page */
1236 page = grab_cache_page_write_begin(mapping, index, 0);
1237 if (!page)
1238 return -ENOMEM;
1239
1240 dout("write_begin file %p inode %p page %p %d~%d\n", file,
1241 inode, page, (int)pos, (int)len);
1242
1243 r = ceph_update_writeable_page(file, pos, len, page);
1244 if (r < 0)
1245 put_page(page);
1246 else
1247 *pagep = page;
1248 } while (r == -EAGAIN);
1249
1250 return r;
1251 }
1252
1253 /*
1254 * we don't do anything in here that simple_write_end doesn't do
1255 * except adjust dirty page accounting
1256 */
1257 static int ceph_write_end(struct file *file, struct address_space *mapping,
1258 loff_t pos, unsigned len, unsigned copied,
1259 struct page *page, void *fsdata)
1260 {
1261 struct inode *inode = file_inode(file);
1262 unsigned from = pos & (PAGE_SIZE - 1);
1263 int check_cap = 0;
1264
1265 dout("write_end file %p inode %p page %p %d~%d (%d)\n", file,
1266 inode, page, (int)pos, (int)copied, (int)len);
1267
1268 /* zero the stale part of the page if we did a short copy */
1269 if (copied < len)
1270 zero_user_segment(page, from+copied, len);
1271
1272 /* did file size increase? */
1273 if (pos+copied > i_size_read(inode))
1274 check_cap = ceph_inode_set_size(inode, pos+copied);
1275
1276 if (!PageUptodate(page))
1277 SetPageUptodate(page);
1278
1279 set_page_dirty(page);
1280
1281 unlock_page(page);
1282 put_page(page);
1283
1284 if (check_cap)
1285 ceph_check_caps(ceph_inode(inode), CHECK_CAPS_AUTHONLY, NULL);
1286
1287 return copied;
1288 }
1289
1290 /*
1291 * we set .direct_IO to indicate direct io is supported, but since we
1292 * intercept O_DIRECT reads and writes early, this function should
1293 * never get called.
1294 */
1295 static ssize_t ceph_direct_io(struct kiocb *iocb, struct iov_iter *iter,
1296 loff_t pos)
1297 {
1298 WARN_ON(1);
1299 return -EINVAL;
1300 }
1301
1302 const struct address_space_operations ceph_aops = {
1303 .readpage = ceph_readpage,
1304 .readpages = ceph_readpages,
1305 .writepage = ceph_writepage,
1306 .writepages = ceph_writepages_start,
1307 .write_begin = ceph_write_begin,
1308 .write_end = ceph_write_end,
1309 .set_page_dirty = ceph_set_page_dirty,
1310 .invalidatepage = ceph_invalidatepage,
1311 .releasepage = ceph_releasepage,
1312 .direct_IO = ceph_direct_io,
1313 };
1314
1315
1316 /*
1317 * vm ops
1318 */
1319 static int ceph_filemap_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
1320 {
1321 struct inode *inode = file_inode(vma->vm_file);
1322 struct ceph_inode_info *ci = ceph_inode(inode);
1323 struct ceph_file_info *fi = vma->vm_file->private_data;
1324 struct page *pinned_page = NULL;
1325 loff_t off = vmf->pgoff << PAGE_SHIFT;
1326 int want, got, ret;
1327
1328 dout("filemap_fault %p %llx.%llx %llu~%zd trying to get caps\n",
1329 inode, ceph_vinop(inode), off, (size_t)PAGE_SIZE);
1330 if (fi->fmode & CEPH_FILE_MODE_LAZY)
1331 want = CEPH_CAP_FILE_CACHE | CEPH_CAP_FILE_LAZYIO;
1332 else
1333 want = CEPH_CAP_FILE_CACHE;
1334 while (1) {
1335 got = 0;
1336 ret = ceph_get_caps(ci, CEPH_CAP_FILE_RD, want,
1337 -1, &got, &pinned_page);
1338 if (ret == 0)
1339 break;
1340 if (ret != -ERESTARTSYS) {
1341 WARN_ON(1);
1342 return VM_FAULT_SIGBUS;
1343 }
1344 }
1345 dout("filemap_fault %p %llu~%zd got cap refs on %s\n",
1346 inode, off, (size_t)PAGE_SIZE, ceph_cap_string(got));
1347
1348 if ((got & (CEPH_CAP_FILE_CACHE | CEPH_CAP_FILE_LAZYIO)) ||
1349 ci->i_inline_version == CEPH_INLINE_NONE)
1350 ret = filemap_fault(vma, vmf);
1351 else
1352 ret = -EAGAIN;
1353
1354 dout("filemap_fault %p %llu~%zd dropping cap refs on %s ret %d\n",
1355 inode, off, (size_t)PAGE_SIZE, ceph_cap_string(got), ret);
1356 if (pinned_page)
1357 put_page(pinned_page);
1358 ceph_put_cap_refs(ci, got);
1359
1360 if (ret != -EAGAIN)
1361 return ret;
1362
1363 /* read inline data */
1364 if (off >= PAGE_SIZE) {
1365 /* does not support inline data > PAGE_SIZE */
1366 ret = VM_FAULT_SIGBUS;
1367 } else {
1368 int ret1;
1369 struct address_space *mapping = inode->i_mapping;
1370 struct page *page = find_or_create_page(mapping, 0,
1371 mapping_gfp_constraint(mapping,
1372 ~__GFP_FS));
1373 if (!page) {
1374 ret = VM_FAULT_OOM;
1375 goto out;
1376 }
1377 ret1 = __ceph_do_getattr(inode, page,
1378 CEPH_STAT_CAP_INLINE_DATA, true);
1379 if (ret1 < 0 || off >= i_size_read(inode)) {
1380 unlock_page(page);
1381 put_page(page);
1382 ret = VM_FAULT_SIGBUS;
1383 goto out;
1384 }
1385 if (ret1 < PAGE_SIZE)
1386 zero_user_segment(page, ret1, PAGE_SIZE);
1387 else
1388 flush_dcache_page(page);
1389 SetPageUptodate(page);
1390 vmf->page = page;
1391 ret = VM_FAULT_MAJOR | VM_FAULT_LOCKED;
1392 }
1393 out:
1394 dout("filemap_fault %p %llu~%zd read inline data ret %d\n",
1395 inode, off, (size_t)PAGE_SIZE, ret);
1396 return ret;
1397 }
1398
1399 /*
1400 * Reuse write_begin here for simplicity.
1401 */
1402 static int ceph_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
1403 {
1404 struct inode *inode = file_inode(vma->vm_file);
1405 struct ceph_inode_info *ci = ceph_inode(inode);
1406 struct ceph_file_info *fi = vma->vm_file->private_data;
1407 struct ceph_cap_flush *prealloc_cf;
1408 struct page *page = vmf->page;
1409 loff_t off = page_offset(page);
1410 loff_t size = i_size_read(inode);
1411 size_t len;
1412 int want, got, ret;
1413
1414 prealloc_cf = ceph_alloc_cap_flush();
1415 if (!prealloc_cf)
1416 return VM_FAULT_SIGBUS;
1417
1418 if (ci->i_inline_version != CEPH_INLINE_NONE) {
1419 struct page *locked_page = NULL;
1420 if (off == 0) {
1421 lock_page(page);
1422 locked_page = page;
1423 }
1424 ret = ceph_uninline_data(vma->vm_file, locked_page);
1425 if (locked_page)
1426 unlock_page(locked_page);
1427 if (ret < 0) {
1428 ret = VM_FAULT_SIGBUS;
1429 goto out_free;
1430 }
1431 }
1432
1433 if (off + PAGE_SIZE <= size)
1434 len = PAGE_SIZE;
1435 else
1436 len = size & ~PAGE_MASK;
1437
1438 dout("page_mkwrite %p %llx.%llx %llu~%zd getting caps i_size %llu\n",
1439 inode, ceph_vinop(inode), off, len, size);
1440 if (fi->fmode & CEPH_FILE_MODE_LAZY)
1441 want = CEPH_CAP_FILE_BUFFER | CEPH_CAP_FILE_LAZYIO;
1442 else
1443 want = CEPH_CAP_FILE_BUFFER;
1444 while (1) {
1445 got = 0;
1446 ret = ceph_get_caps(ci, CEPH_CAP_FILE_WR, want, off + len,
1447 &got, NULL);
1448 if (ret == 0)
1449 break;
1450 if (ret != -ERESTARTSYS) {
1451 WARN_ON(1);
1452 ret = VM_FAULT_SIGBUS;
1453 goto out_free;
1454 }
1455 }
1456 dout("page_mkwrite %p %llu~%zd got cap refs on %s\n",
1457 inode, off, len, ceph_cap_string(got));
1458
1459 /* Update time before taking page lock */
1460 file_update_time(vma->vm_file);
1461
1462 lock_page(page);
1463
1464 ret = VM_FAULT_NOPAGE;
1465 if ((off > size) ||
1466 (page->mapping != inode->i_mapping)) {
1467 unlock_page(page);
1468 goto out;
1469 }
1470
1471 ret = ceph_update_writeable_page(vma->vm_file, off, len, page);
1472 if (ret >= 0) {
1473 /* success. we'll keep the page locked. */
1474 set_page_dirty(page);
1475 ret = VM_FAULT_LOCKED;
1476 } else {
1477 if (ret == -ENOMEM)
1478 ret = VM_FAULT_OOM;
1479 else
1480 ret = VM_FAULT_SIGBUS;
1481 }
1482 out:
1483 if (ret == VM_FAULT_LOCKED ||
1484 ci->i_inline_version != CEPH_INLINE_NONE) {
1485 int dirty;
1486 spin_lock(&ci->i_ceph_lock);
1487 ci->i_inline_version = CEPH_INLINE_NONE;
1488 dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_FILE_WR,
1489 &prealloc_cf);
1490 spin_unlock(&ci->i_ceph_lock);
1491 if (dirty)
1492 __mark_inode_dirty(inode, dirty);
1493 }
1494
1495 dout("page_mkwrite %p %llu~%zd dropping cap refs on %s ret %d\n",
1496 inode, off, len, ceph_cap_string(got), ret);
1497 ceph_put_cap_refs(ci, got);
1498 out_free:
1499 ceph_free_cap_flush(prealloc_cf);
1500
1501 return ret;
1502 }
1503
1504 void ceph_fill_inline_data(struct inode *inode, struct page *locked_page,
1505 char *data, size_t len)
1506 {
1507 struct address_space *mapping = inode->i_mapping;
1508 struct page *page;
1509
1510 if (locked_page) {
1511 page = locked_page;
1512 } else {
1513 if (i_size_read(inode) == 0)
1514 return;
1515 page = find_or_create_page(mapping, 0,
1516 mapping_gfp_constraint(mapping,
1517 ~__GFP_FS));
1518 if (!page)
1519 return;
1520 if (PageUptodate(page)) {
1521 unlock_page(page);
1522 put_page(page);
1523 return;
1524 }
1525 }
1526
1527 dout("fill_inline_data %p %llx.%llx len %zu locked_page %p\n",
1528 inode, ceph_vinop(inode), len, locked_page);
1529
1530 if (len > 0) {
1531 void *kaddr = kmap_atomic(page);
1532 memcpy(kaddr, data, len);
1533 kunmap_atomic(kaddr);
1534 }
1535
1536 if (page != locked_page) {
1537 if (len < PAGE_SIZE)
1538 zero_user_segment(page, len, PAGE_SIZE);
1539 else
1540 flush_dcache_page(page);
1541
1542 SetPageUptodate(page);
1543 unlock_page(page);
1544 put_page(page);
1545 }
1546 }
1547
1548 int ceph_uninline_data(struct file *filp, struct page *locked_page)
1549 {
1550 struct inode *inode = file_inode(filp);
1551 struct ceph_inode_info *ci = ceph_inode(inode);
1552 struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
1553 struct ceph_osd_request *req;
1554 struct page *page = NULL;
1555 u64 len, inline_version;
1556 int err = 0;
1557 bool from_pagecache = false;
1558
1559 spin_lock(&ci->i_ceph_lock);
1560 inline_version = ci->i_inline_version;
1561 spin_unlock(&ci->i_ceph_lock);
1562
1563 dout("uninline_data %p %llx.%llx inline_version %llu\n",
1564 inode, ceph_vinop(inode), inline_version);
1565
1566 if (inline_version == 1 || /* initial version, no data */
1567 inline_version == CEPH_INLINE_NONE)
1568 goto out;
1569
1570 if (locked_page) {
1571 page = locked_page;
1572 WARN_ON(!PageUptodate(page));
1573 } else if (ceph_caps_issued(ci) &
1574 (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)) {
1575 page = find_get_page(inode->i_mapping, 0);
1576 if (page) {
1577 if (PageUptodate(page)) {
1578 from_pagecache = true;
1579 lock_page(page);
1580 } else {
1581 put_page(page);
1582 page = NULL;
1583 }
1584 }
1585 }
1586
1587 if (page) {
1588 len = i_size_read(inode);
1589 if (len > PAGE_SIZE)
1590 len = PAGE_SIZE;
1591 } else {
1592 page = __page_cache_alloc(GFP_NOFS);
1593 if (!page) {
1594 err = -ENOMEM;
1595 goto out;
1596 }
1597 err = __ceph_do_getattr(inode, page,
1598 CEPH_STAT_CAP_INLINE_DATA, true);
1599 if (err < 0) {
1600 /* no inline data */
1601 if (err == -ENODATA)
1602 err = 0;
1603 goto out;
1604 }
1605 len = err;
1606 }
1607
1608 req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout,
1609 ceph_vino(inode), 0, &len, 0, 1,
1610 CEPH_OSD_OP_CREATE,
1611 CEPH_OSD_FLAG_ONDISK | CEPH_OSD_FLAG_WRITE,
1612 NULL, 0, 0, false);
1613 if (IS_ERR(req)) {
1614 err = PTR_ERR(req);
1615 goto out;
1616 }
1617
1618 ceph_osdc_build_request(req, 0, NULL, CEPH_NOSNAP, &inode->i_mtime);
1619 err = ceph_osdc_start_request(&fsc->client->osdc, req, false);
1620 if (!err)
1621 err = ceph_osdc_wait_request(&fsc->client->osdc, req);
1622 ceph_osdc_put_request(req);
1623 if (err < 0)
1624 goto out;
1625
1626 req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout,
1627 ceph_vino(inode), 0, &len, 1, 3,
1628 CEPH_OSD_OP_WRITE,
1629 CEPH_OSD_FLAG_ONDISK | CEPH_OSD_FLAG_WRITE,
1630 NULL, ci->i_truncate_seq,
1631 ci->i_truncate_size, false);
1632 if (IS_ERR(req)) {
1633 err = PTR_ERR(req);
1634 goto out;
1635 }
1636
1637 osd_req_op_extent_osd_data_pages(req, 1, &page, len, 0, false, false);
1638
1639 {
1640 __le64 xattr_buf = cpu_to_le64(inline_version);
1641 err = osd_req_op_xattr_init(req, 0, CEPH_OSD_OP_CMPXATTR,
1642 "inline_version", &xattr_buf,
1643 sizeof(xattr_buf),
1644 CEPH_OSD_CMPXATTR_OP_GT,
1645 CEPH_OSD_CMPXATTR_MODE_U64);
1646 if (err)
1647 goto out_put;
1648 }
1649
1650 {
1651 char xattr_buf[32];
1652 int xattr_len = snprintf(xattr_buf, sizeof(xattr_buf),
1653 "%llu", inline_version);
1654 err = osd_req_op_xattr_init(req, 2, CEPH_OSD_OP_SETXATTR,
1655 "inline_version",
1656 xattr_buf, xattr_len, 0, 0);
1657 if (err)
1658 goto out_put;
1659 }
1660
1661 ceph_osdc_build_request(req, 0, NULL, CEPH_NOSNAP, &inode->i_mtime);
1662 err = ceph_osdc_start_request(&fsc->client->osdc, req, false);
1663 if (!err)
1664 err = ceph_osdc_wait_request(&fsc->client->osdc, req);
1665 out_put:
1666 ceph_osdc_put_request(req);
1667 if (err == -ECANCELED)
1668 err = 0;
1669 out:
1670 if (page && page != locked_page) {
1671 if (from_pagecache) {
1672 unlock_page(page);
1673 put_page(page);
1674 } else
1675 __free_pages(page, 0);
1676 }
1677
1678 dout("uninline_data %p %llx.%llx inline_version %llu = %d\n",
1679 inode, ceph_vinop(inode), inline_version, err);
1680 return err;
1681 }
1682
1683 static const struct vm_operations_struct ceph_vmops = {
1684 .fault = ceph_filemap_fault,
1685 .page_mkwrite = ceph_page_mkwrite,
1686 };
1687
1688 int ceph_mmap(struct file *file, struct vm_area_struct *vma)
1689 {
1690 struct address_space *mapping = file->f_mapping;
1691
1692 if (!mapping->a_ops->readpage)
1693 return -ENOEXEC;
1694 file_accessed(file);
1695 vma->vm_ops = &ceph_vmops;
1696 return 0;
1697 }
1698
1699 enum {
1700 POOL_READ = 1,
1701 POOL_WRITE = 2,
1702 };
1703
1704 static int __ceph_pool_perm_get(struct ceph_inode_info *ci, u32 pool)
1705 {
1706 struct ceph_fs_client *fsc = ceph_inode_to_client(&ci->vfs_inode);
1707 struct ceph_mds_client *mdsc = fsc->mdsc;
1708 struct ceph_osd_request *rd_req = NULL, *wr_req = NULL;
1709 struct rb_node **p, *parent;
1710 struct ceph_pool_perm *perm;
1711 struct page **pages;
1712 int err = 0, err2 = 0, have = 0;
1713
1714 down_read(&mdsc->pool_perm_rwsem);
1715 p = &mdsc->pool_perm_tree.rb_node;
1716 while (*p) {
1717 perm = rb_entry(*p, struct ceph_pool_perm, node);
1718 if (pool < perm->pool)
1719 p = &(*p)->rb_left;
1720 else if (pool > perm->pool)
1721 p = &(*p)->rb_right;
1722 else {
1723 have = perm->perm;
1724 break;
1725 }
1726 }
1727 up_read(&mdsc->pool_perm_rwsem);
1728 if (*p)
1729 goto out;
1730
1731 dout("__ceph_pool_perm_get pool %u no perm cached\n", pool);
1732
1733 down_write(&mdsc->pool_perm_rwsem);
1734 parent = NULL;
1735 while (*p) {
1736 parent = *p;
1737 perm = rb_entry(parent, struct ceph_pool_perm, node);
1738 if (pool < perm->pool)
1739 p = &(*p)->rb_left;
1740 else if (pool > perm->pool)
1741 p = &(*p)->rb_right;
1742 else {
1743 have = perm->perm;
1744 break;
1745 }
1746 }
1747 if (*p) {
1748 up_write(&mdsc->pool_perm_rwsem);
1749 goto out;
1750 }
1751
1752 rd_req = ceph_osdc_alloc_request(&fsc->client->osdc, NULL,
1753 1, false, GFP_NOFS);
1754 if (!rd_req) {
1755 err = -ENOMEM;
1756 goto out_unlock;
1757 }
1758
1759 rd_req->r_flags = CEPH_OSD_FLAG_READ;
1760 osd_req_op_init(rd_req, 0, CEPH_OSD_OP_STAT, 0);
1761 rd_req->r_base_oloc.pool = pool;
1762 snprintf(rd_req->r_base_oid.name, sizeof(rd_req->r_base_oid.name),
1763 "%llx.00000000", ci->i_vino.ino);
1764 rd_req->r_base_oid.name_len = strlen(rd_req->r_base_oid.name);
1765
1766 wr_req = ceph_osdc_alloc_request(&fsc->client->osdc, NULL,
1767 1, false, GFP_NOFS);
1768 if (!wr_req) {
1769 err = -ENOMEM;
1770 goto out_unlock;
1771 }
1772
1773 wr_req->r_flags = CEPH_OSD_FLAG_WRITE |
1774 CEPH_OSD_FLAG_ACK | CEPH_OSD_FLAG_ONDISK;
1775 osd_req_op_init(wr_req, 0, CEPH_OSD_OP_CREATE, CEPH_OSD_OP_FLAG_EXCL);
1776 wr_req->r_base_oloc.pool = pool;
1777 wr_req->r_base_oid = rd_req->r_base_oid;
1778
1779 /* one page should be large enough for STAT data */
1780 pages = ceph_alloc_page_vector(1, GFP_KERNEL);
1781 if (IS_ERR(pages)) {
1782 err = PTR_ERR(pages);
1783 goto out_unlock;
1784 }
1785
1786 osd_req_op_raw_data_in_pages(rd_req, 0, pages, PAGE_SIZE,
1787 0, false, true);
1788 ceph_osdc_build_request(rd_req, 0, NULL, CEPH_NOSNAP,
1789 &ci->vfs_inode.i_mtime);
1790 err = ceph_osdc_start_request(&fsc->client->osdc, rd_req, false);
1791
1792 ceph_osdc_build_request(wr_req, 0, NULL, CEPH_NOSNAP,
1793 &ci->vfs_inode.i_mtime);
1794 err2 = ceph_osdc_start_request(&fsc->client->osdc, wr_req, false);
1795
1796 if (!err)
1797 err = ceph_osdc_wait_request(&fsc->client->osdc, rd_req);
1798 if (!err2)
1799 err2 = ceph_osdc_wait_request(&fsc->client->osdc, wr_req);
1800
1801 if (err >= 0 || err == -ENOENT)
1802 have |= POOL_READ;
1803 else if (err != -EPERM)
1804 goto out_unlock;
1805
1806 if (err2 == 0 || err2 == -EEXIST)
1807 have |= POOL_WRITE;
1808 else if (err2 != -EPERM) {
1809 err = err2;
1810 goto out_unlock;
1811 }
1812
1813 perm = kmalloc(sizeof(*perm), GFP_NOFS);
1814 if (!perm) {
1815 err = -ENOMEM;
1816 goto out_unlock;
1817 }
1818
1819 perm->pool = pool;
1820 perm->perm = have;
1821 rb_link_node(&perm->node, parent, p);
1822 rb_insert_color(&perm->node, &mdsc->pool_perm_tree);
1823 err = 0;
1824 out_unlock:
1825 up_write(&mdsc->pool_perm_rwsem);
1826
1827 if (rd_req)
1828 ceph_osdc_put_request(rd_req);
1829 if (wr_req)
1830 ceph_osdc_put_request(wr_req);
1831 out:
1832 if (!err)
1833 err = have;
1834 dout("__ceph_pool_perm_get pool %u result = %d\n", pool, err);
1835 return err;
1836 }
1837
1838 int ceph_pool_perm_check(struct ceph_inode_info *ci, int need)
1839 {
1840 u32 pool;
1841 int ret, flags;
1842
1843 /* does not support pool namespace yet */
1844 if (ci->i_pool_ns_len)
1845 return -EIO;
1846
1847 if (ceph_test_mount_opt(ceph_inode_to_client(&ci->vfs_inode),
1848 NOPOOLPERM))
1849 return 0;
1850
1851 spin_lock(&ci->i_ceph_lock);
1852 flags = ci->i_ceph_flags;
1853 pool = ceph_file_layout_pg_pool(ci->i_layout);
1854 spin_unlock(&ci->i_ceph_lock);
1855 check:
1856 if (flags & CEPH_I_POOL_PERM) {
1857 if ((need & CEPH_CAP_FILE_RD) && !(flags & CEPH_I_POOL_RD)) {
1858 dout("ceph_pool_perm_check pool %u no read perm\n",
1859 pool);
1860 return -EPERM;
1861 }
1862 if ((need & CEPH_CAP_FILE_WR) && !(flags & CEPH_I_POOL_WR)) {
1863 dout("ceph_pool_perm_check pool %u no write perm\n",
1864 pool);
1865 return -EPERM;
1866 }
1867 return 0;
1868 }
1869
1870 ret = __ceph_pool_perm_get(ci, pool);
1871 if (ret < 0)
1872 return ret;
1873
1874 flags = CEPH_I_POOL_PERM;
1875 if (ret & POOL_READ)
1876 flags |= CEPH_I_POOL_RD;
1877 if (ret & POOL_WRITE)
1878 flags |= CEPH_I_POOL_WR;
1879
1880 spin_lock(&ci->i_ceph_lock);
1881 if (pool == ceph_file_layout_pg_pool(ci->i_layout)) {
1882 ci->i_ceph_flags = flags;
1883 } else {
1884 pool = ceph_file_layout_pg_pool(ci->i_layout);
1885 flags = ci->i_ceph_flags;
1886 }
1887 spin_unlock(&ci->i_ceph_lock);
1888 goto check;
1889 }
1890
1891 void ceph_pool_perm_destroy(struct ceph_mds_client *mdsc)
1892 {
1893 struct ceph_pool_perm *perm;
1894 struct rb_node *n;
1895
1896 while (!RB_EMPTY_ROOT(&mdsc->pool_perm_tree)) {
1897 n = rb_first(&mdsc->pool_perm_tree);
1898 perm = rb_entry(n, struct ceph_pool_perm, node);
1899 rb_erase(n, &mdsc->pool_perm_tree);
1900 kfree(perm);
1901 }
1902 }
Linux with added FPC-III support