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Linux 3.16-rc2
[linux/fpc-iii.git] / fs / ceph / file.c
blob302085100c28af1a2ed67269e955b3d0839539be
1 #include <linux/ceph/ceph_debug.h>
2
3 #include <linux/module.h>
4 #include <linux/sched.h>
5 #include <linux/slab.h>
6 #include <linux/file.h>
7 #include <linux/mount.h>
8 #include <linux/namei.h>
9 #include <linux/writeback.h>
10 #include <linux/aio.h>
11 #include <linux/falloc.h>
12
13 #include "super.h"
14 #include "mds_client.h"
15 #include "cache.h"
16
17 /*
18 * Ceph file operations
19 *
20 * Implement basic open/close functionality, and implement
21 * read/write.
22 *
23 * We implement three modes of file I/O:
24 * - buffered uses the generic_file_aio_{read,write} helpers
25 *
26 * - synchronous is used when there is multi-client read/write
27 * sharing, avoids the page cache, and synchronously waits for an
28 * ack from the OSD.
29 *
30 * - direct io takes the variant of the sync path that references
31 * user pages directly.
32 *
33 * fsync() flushes and waits on dirty pages, but just queues metadata
34 * for writeback: since the MDS can recover size and mtime there is no
35 * need to wait for MDS acknowledgement.
36 */
37
38
39 /*
40 * Prepare an open request. Preallocate ceph_cap to avoid an
41 * inopportune ENOMEM later.
42 */
43 static struct ceph_mds_request *
44 prepare_open_request(struct super_block *sb, int flags, int create_mode)
45 {
46 struct ceph_fs_client *fsc = ceph_sb_to_client(sb);
47 struct ceph_mds_client *mdsc = fsc->mdsc;
48 struct ceph_mds_request *req;
49 int want_auth = USE_ANY_MDS;
50 int op = (flags & O_CREAT) ? CEPH_MDS_OP_CREATE : CEPH_MDS_OP_OPEN;
51
52 if (flags & (O_WRONLY|O_RDWR|O_CREAT|O_TRUNC))
53 want_auth = USE_AUTH_MDS;
54
55 req = ceph_mdsc_create_request(mdsc, op, want_auth);
56 if (IS_ERR(req))
57 goto out;
58 req->r_fmode = ceph_flags_to_mode(flags);
59 req->r_args.open.flags = cpu_to_le32(flags);
60 req->r_args.open.mode = cpu_to_le32(create_mode);
61 out:
62 return req;
63 }
64
65 /*
66 * initialize private struct file data.
67 * if we fail, clean up by dropping fmode reference on the ceph_inode
68 */
69 static int ceph_init_file(struct inode *inode, struct file *file, int fmode)
70 {
71 struct ceph_file_info *cf;
72 int ret = 0;
73 struct ceph_inode_info *ci = ceph_inode(inode);
74 struct ceph_fs_client *fsc = ceph_sb_to_client(inode->i_sb);
75 struct ceph_mds_client *mdsc = fsc->mdsc;
76
77 switch (inode->i_mode & S_IFMT) {
78 case S_IFREG:
79 /* First file open request creates the cookie, we want to keep
80 * this cookie around for the filetime of the inode as not to
81 * have to worry about fscache register / revoke / operation
82 * races.
83 *
84 * Also, if we know the operation is going to invalidate data
85 * (non readonly) just nuke the cache right away.
86 */
87 ceph_fscache_register_inode_cookie(mdsc->fsc, ci);
88 if ((fmode & CEPH_FILE_MODE_WR))
89 ceph_fscache_invalidate(inode);
90 case S_IFDIR:
91 dout("init_file %p %p 0%o (regular)\n", inode, file,
92 inode->i_mode);
93 cf = kmem_cache_alloc(ceph_file_cachep, GFP_NOFS | __GFP_ZERO);
94 if (cf == NULL) {
95 ceph_put_fmode(ceph_inode(inode), fmode); /* clean up */
96 return -ENOMEM;
97 }
98 cf->fmode = fmode;
99 cf->next_offset = 2;
100 file->private_data = cf;
101 BUG_ON(inode->i_fop->release != ceph_release);
102 break;
103
104 case S_IFLNK:
105 dout("init_file %p %p 0%o (symlink)\n", inode, file,
106 inode->i_mode);
107 ceph_put_fmode(ceph_inode(inode), fmode); /* clean up */
108 break;
109
110 default:
111 dout("init_file %p %p 0%o (special)\n", inode, file,
112 inode->i_mode);
113 /*
114 * we need to drop the open ref now, since we don't
115 * have .release set to ceph_release.
116 */
117 ceph_put_fmode(ceph_inode(inode), fmode); /* clean up */
118 BUG_ON(inode->i_fop->release == ceph_release);
119
120 /* call the proper open fop */
121 ret = inode->i_fop->open(inode, file);
122 }
123 return ret;
124 }
125
126 /*
127 * If we already have the requisite capabilities, we can satisfy
128 * the open request locally (no need to request new caps from the
129 * MDS). We do, however, need to inform the MDS (asynchronously)
130 * if our wanted caps set expands.
131 */
132 int ceph_open(struct inode *inode, struct file *file)
133 {
134 struct ceph_inode_info *ci = ceph_inode(inode);
135 struct ceph_fs_client *fsc = ceph_sb_to_client(inode->i_sb);
136 struct ceph_mds_client *mdsc = fsc->mdsc;
137 struct ceph_mds_request *req;
138 struct ceph_file_info *cf = file->private_data;
139 struct inode *parent_inode = NULL;
140 int err;
141 int flags, fmode, wanted;
142
143 if (cf) {
144 dout("open file %p is already opened\n", file);
145 return 0;
146 }
147
148 /* filter out O_CREAT|O_EXCL; vfs did that already. yuck. */
149 flags = file->f_flags & ~(O_CREAT|O_EXCL);
150 if (S_ISDIR(inode->i_mode))
151 flags = O_DIRECTORY; /* mds likes to know */
152
153 dout("open inode %p ino %llx.%llx file %p flags %d (%d)\n", inode,
154 ceph_vinop(inode), file, flags, file->f_flags);
155 fmode = ceph_flags_to_mode(flags);
156 wanted = ceph_caps_for_mode(fmode);
157
158 /* snapped files are read-only */
159 if (ceph_snap(inode) != CEPH_NOSNAP && (file->f_mode & FMODE_WRITE))
160 return -EROFS;
161
162 /* trivially open snapdir */
163 if (ceph_snap(inode) == CEPH_SNAPDIR) {
164 spin_lock(&ci->i_ceph_lock);
165 __ceph_get_fmode(ci, fmode);
166 spin_unlock(&ci->i_ceph_lock);
167 return ceph_init_file(inode, file, fmode);
168 }
169
170 /*
171 * No need to block if we have caps on the auth MDS (for
172 * write) or any MDS (for read). Update wanted set
173 * asynchronously.
174 */
175 spin_lock(&ci->i_ceph_lock);
176 if (__ceph_is_any_real_caps(ci) &&
177 (((fmode & CEPH_FILE_MODE_WR) == 0) || ci->i_auth_cap)) {
178 int mds_wanted = __ceph_caps_mds_wanted(ci);
179 int issued = __ceph_caps_issued(ci, NULL);
180
181 dout("open %p fmode %d want %s issued %s using existing\n",
182 inode, fmode, ceph_cap_string(wanted),
183 ceph_cap_string(issued));
184 __ceph_get_fmode(ci, fmode);
185 spin_unlock(&ci->i_ceph_lock);
186
187 /* adjust wanted? */
188 if ((issued & wanted) != wanted &&
189 (mds_wanted & wanted) != wanted &&
190 ceph_snap(inode) != CEPH_SNAPDIR)
191 ceph_check_caps(ci, 0, NULL);
192
193 return ceph_init_file(inode, file, fmode);
194 } else if (ceph_snap(inode) != CEPH_NOSNAP &&
195 (ci->i_snap_caps & wanted) == wanted) {
196 __ceph_get_fmode(ci, fmode);
197 spin_unlock(&ci->i_ceph_lock);
198 return ceph_init_file(inode, file, fmode);
199 }
200
201 spin_unlock(&ci->i_ceph_lock);
202
203 dout("open fmode %d wants %s\n", fmode, ceph_cap_string(wanted));
204 req = prepare_open_request(inode->i_sb, flags, 0);
205 if (IS_ERR(req)) {
206 err = PTR_ERR(req);
207 goto out;
208 }
209 req->r_inode = inode;
210 ihold(inode);
211
212 req->r_num_caps = 1;
213 if (flags & O_CREAT)
214 parent_inode = ceph_get_dentry_parent_inode(file->f_dentry);
215 err = ceph_mdsc_do_request(mdsc, parent_inode, req);
216 iput(parent_inode);
217 if (!err)
218 err = ceph_init_file(inode, file, req->r_fmode);
219 ceph_mdsc_put_request(req);
220 dout("open result=%d on %llx.%llx\n", err, ceph_vinop(inode));
221 out:
222 return err;
223 }
224
225
226 /*
227 * Do a lookup + open with a single request. If we get a non-existent
228 * file or symlink, return 1 so the VFS can retry.
229 */
230 int ceph_atomic_open(struct inode *dir, struct dentry *dentry,
231 struct file *file, unsigned flags, umode_t mode,
232 int *opened)
233 {
234 struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
235 struct ceph_mds_client *mdsc = fsc->mdsc;
236 struct ceph_mds_request *req;
237 struct dentry *dn;
238 int err;
239
240 dout("atomic_open %p dentry %p '%.*s' %s flags %d mode 0%o\n",
241 dir, dentry, dentry->d_name.len, dentry->d_name.name,
242 d_unhashed(dentry) ? "unhashed" : "hashed", flags, mode);
243
244 if (dentry->d_name.len > NAME_MAX)
245 return -ENAMETOOLONG;
246
247 err = ceph_init_dentry(dentry);
248 if (err < 0)
249 return err;
250
251 /* do the open */
252 req = prepare_open_request(dir->i_sb, flags, mode);
253 if (IS_ERR(req))
254 return PTR_ERR(req);
255 req->r_dentry = dget(dentry);
256 req->r_num_caps = 2;
257 if (flags & O_CREAT) {
258 req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
259 req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
260 }
261 req->r_locked_dir = dir; /* caller holds dir->i_mutex */
262 err = ceph_mdsc_do_request(mdsc,
263 (flags & (O_CREAT|O_TRUNC)) ? dir : NULL,
264 req);
265 if (err)
266 goto out_err;
267
268 err = ceph_handle_snapdir(req, dentry, err);
269 if (err == 0 && (flags & O_CREAT) && !req->r_reply_info.head->is_dentry)
270 err = ceph_handle_notrace_create(dir, dentry);
271
272 if (d_unhashed(dentry)) {
273 dn = ceph_finish_lookup(req, dentry, err);
274 if (IS_ERR(dn))
275 err = PTR_ERR(dn);
276 } else {
277 /* we were given a hashed negative dentry */
278 dn = NULL;
279 }
280 if (err)
281 goto out_err;
282 if (dn || dentry->d_inode == NULL || S_ISLNK(dentry->d_inode->i_mode)) {
283 /* make vfs retry on splice, ENOENT, or symlink */
284 dout("atomic_open finish_no_open on dn %p\n", dn);
285 err = finish_no_open(file, dn);
286 } else {
287 dout("atomic_open finish_open on dn %p\n", dn);
288 if (req->r_op == CEPH_MDS_OP_CREATE && req->r_reply_info.has_create_ino) {
289 ceph_init_acl(dentry, dentry->d_inode, dir);
290 *opened |= FILE_CREATED;
291 }
292 err = finish_open(file, dentry, ceph_open, opened);
293 }
294 out_err:
295 if (!req->r_err && req->r_target_inode)
296 ceph_put_fmode(ceph_inode(req->r_target_inode), req->r_fmode);
297 ceph_mdsc_put_request(req);
298 dout("atomic_open result=%d\n", err);
299 return err;
300 }
301
302 int ceph_release(struct inode *inode, struct file *file)
303 {
304 struct ceph_inode_info *ci = ceph_inode(inode);
305 struct ceph_file_info *cf = file->private_data;
306
307 dout("release inode %p file %p\n", inode, file);
308 ceph_put_fmode(ci, cf->fmode);
309 if (cf->last_readdir)
310 ceph_mdsc_put_request(cf->last_readdir);
311 kfree(cf->last_name);
312 kfree(cf->dir_info);
313 dput(cf->dentry);
314 kmem_cache_free(ceph_file_cachep, cf);
315
316 /* wake up anyone waiting for caps on this inode */
317 wake_up_all(&ci->i_cap_wq);
318 return 0;
319 }
320
321 /*
322 * Read a range of bytes striped over one or more objects. Iterate over
323 * objects we stripe over. (That's not atomic, but good enough for now.)
324 *
325 * If we get a short result from the OSD, check against i_size; we need to
326 * only return a short read to the caller if we hit EOF.
327 */
328 static int striped_read(struct inode *inode,
329 u64 off, u64 len,
330 struct page **pages, int num_pages,
331 int *checkeof, bool o_direct,
332 unsigned long buf_align)
333 {
334 struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
335 struct ceph_inode_info *ci = ceph_inode(inode);
336 u64 pos, this_len, left;
337 int io_align, page_align;
338 int pages_left;
339 int read;
340 struct page **page_pos;
341 int ret;
342 bool hit_stripe, was_short;
343
344 /*
345 * we may need to do multiple reads. not atomic, unfortunately.
346 */
347 pos = off;
348 left = len;
349 page_pos = pages;
350 pages_left = num_pages;
351 read = 0;
352 io_align = off & ~PAGE_MASK;
353
354 more:
355 if (o_direct)
356 page_align = (pos - io_align + buf_align) & ~PAGE_MASK;
357 else
358 page_align = pos & ~PAGE_MASK;
359 this_len = left;
360 ret = ceph_osdc_readpages(&fsc->client->osdc, ceph_vino(inode),
361 &ci->i_layout, pos, &this_len,
362 ci->i_truncate_seq,
363 ci->i_truncate_size,
364 page_pos, pages_left, page_align);
365 if (ret == -ENOENT)
366 ret = 0;
367 hit_stripe = this_len < left;
368 was_short = ret >= 0 && ret < this_len;
369 dout("striped_read %llu~%llu (read %u) got %d%s%s\n", pos, left, read,
370 ret, hit_stripe ? " HITSTRIPE" : "", was_short ? " SHORT" : "");
371
372 if (ret >= 0) {
373 int didpages;
374 if (was_short && (pos + ret < inode->i_size)) {
375 u64 tmp = min(this_len - ret,
376 inode->i_size - pos - ret);
377 dout(" zero gap %llu to %llu\n",
378 pos + ret, pos + ret + tmp);
379 ceph_zero_page_vector_range(page_align + read + ret,
380 tmp, pages);
381 ret += tmp;
382 }
383
384 didpages = (page_align + ret) >> PAGE_CACHE_SHIFT;
385 pos += ret;
386 read = pos - off;
387 left -= ret;
388 page_pos += didpages;
389 pages_left -= didpages;
390
391 /* hit stripe and need continue*/
392 if (left && hit_stripe && pos < inode->i_size)
393 goto more;
394 }
395
396 if (read > 0) {
397 ret = read;
398 /* did we bounce off eof? */
399 if (pos + left > inode->i_size)
400 *checkeof = 1;
401 }
402
403 dout("striped_read returns %d\n", ret);
404 return ret;
405 }
406
407 /*
408 * Completely synchronous read and write methods. Direct from __user
409 * buffer to osd, or directly to user pages (if O_DIRECT).
410 *
411 * If the read spans object boundary, just do multiple reads.
412 */
413 static ssize_t ceph_sync_read(struct kiocb *iocb, struct iov_iter *i,
414 int *checkeof)
415 {
416 struct file *file = iocb->ki_filp;
417 struct inode *inode = file_inode(file);
418 struct page **pages;
419 u64 off = iocb->ki_pos;
420 int num_pages, ret;
421 size_t len = iov_iter_count(i);
422
423 dout("sync_read on file %p %llu~%u %s\n", file, off,
424 (unsigned)len,
425 (file->f_flags & O_DIRECT) ? "O_DIRECT" : "");
426 /*
427 * flush any page cache pages in this range. this
428 * will make concurrent normal and sync io slow,
429 * but it will at least behave sensibly when they are
430 * in sequence.
431 */
432 ret = filemap_write_and_wait_range(inode->i_mapping, off,
433 off + len);
434 if (ret < 0)
435 return ret;
436
437 if (file->f_flags & O_DIRECT) {
438 while (iov_iter_count(i)) {
439 size_t start;
440 ssize_t n;
441
442 n = iov_iter_get_pages_alloc(i, &pages, INT_MAX, &start);
443 if (n < 0)
444 return n;
445
446 num_pages = (n + start + PAGE_SIZE - 1) / PAGE_SIZE;
447
448 ret = striped_read(inode, off, n,
449 pages, num_pages, checkeof,
450 1, start);
451
452 ceph_put_page_vector(pages, num_pages, true);
453
454 if (ret <= 0)
455 break;
456 off += ret;
457 iov_iter_advance(i, ret);
458 if (ret < n)
459 break;
460 }
461 } else {
462 num_pages = calc_pages_for(off, len);
463 pages = ceph_alloc_page_vector(num_pages, GFP_NOFS);
464 if (IS_ERR(pages))
465 return PTR_ERR(pages);
466 ret = striped_read(inode, off, len, pages,
467 num_pages, checkeof, 0, 0);
468 if (ret > 0) {
469 int l, k = 0;
470 size_t left = ret;
471
472 while (left) {
473 int copy = min_t(size_t, PAGE_SIZE, left);
474 l = copy_page_to_iter(pages[k++], 0, copy, i);
475 off += l;
476 left -= l;
477 if (l < copy)
478 break;
479 }
480 }
481 ceph_release_page_vector(pages, num_pages);
482 }
483
484 if (off > iocb->ki_pos) {
485 ret = off - iocb->ki_pos;
486 iocb->ki_pos = off;
487 }
488
489 dout("sync_read result %d\n", ret);
490 return ret;
491 }
492
493 /*
494 * Write commit request unsafe callback, called to tell us when a
495 * request is unsafe (that is, in flight--has been handed to the
496 * messenger to send to its target osd). It is called again when
497 * we've received a response message indicating the request is
498 * "safe" (its CEPH_OSD_FLAG_ONDISK flag is set), or when a request
499 * is completed early (and unsuccessfully) due to a timeout or
500 * interrupt.
501 *
502 * This is used if we requested both an ACK and ONDISK commit reply
503 * from the OSD.
504 */
505 static void ceph_sync_write_unsafe(struct ceph_osd_request *req, bool unsafe)
506 {
507 struct ceph_inode_info *ci = ceph_inode(req->r_inode);
508
509 dout("%s %p tid %llu %ssafe\n", __func__, req, req->r_tid,
510 unsafe ? "un" : "");
511 if (unsafe) {
512 ceph_get_cap_refs(ci, CEPH_CAP_FILE_WR);
513 spin_lock(&ci->i_unsafe_lock);
514 list_add_tail(&req->r_unsafe_item,
515 &ci->i_unsafe_writes);
516 spin_unlock(&ci->i_unsafe_lock);
517 } else {
518 spin_lock(&ci->i_unsafe_lock);
519 list_del_init(&req->r_unsafe_item);
520 spin_unlock(&ci->i_unsafe_lock);
521 ceph_put_cap_refs(ci, CEPH_CAP_FILE_WR);
522 }
523 }
524
525
526 /*
527 * Synchronous write, straight from __user pointer or user pages.
528 *
529 * If write spans object boundary, just do multiple writes. (For a
530 * correct atomic write, we should e.g. take write locks on all
531 * objects, rollback on failure, etc.)
532 */
533 static ssize_t
534 ceph_sync_direct_write(struct kiocb *iocb, struct iov_iter *from)
535 {
536 struct file *file = iocb->ki_filp;
537 struct inode *inode = file_inode(file);
538 struct ceph_inode_info *ci = ceph_inode(inode);
539 struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
540 struct ceph_snap_context *snapc;
541 struct ceph_vino vino;
542 struct ceph_osd_request *req;
543 struct page **pages;
544 int num_pages;
545 int written = 0;
546 int flags;
547 int check_caps = 0;
548 int ret;
549 struct timespec mtime = CURRENT_TIME;
550 loff_t pos = iocb->ki_pos;
551 size_t count = iov_iter_count(from);
552
553 if (ceph_snap(file_inode(file)) != CEPH_NOSNAP)
554 return -EROFS;
555
556 dout("sync_direct_write on file %p %lld~%u\n", file, pos,
557 (unsigned)count);
558
559 ret = filemap_write_and_wait_range(inode->i_mapping, pos, pos + count);
560 if (ret < 0)
561 return ret;
562
563 ret = invalidate_inode_pages2_range(inode->i_mapping,
564 pos >> PAGE_CACHE_SHIFT,
565 (pos + count) >> PAGE_CACHE_SHIFT);
566 if (ret < 0)
567 dout("invalidate_inode_pages2_range returned %d\n", ret);
568
569 flags = CEPH_OSD_FLAG_ORDERSNAP |
570 CEPH_OSD_FLAG_ONDISK |
571 CEPH_OSD_FLAG_WRITE;
572
573 while (iov_iter_count(from) > 0) {
574 u64 len = iov_iter_single_seg_count(from);
575 size_t start;
576 ssize_t n;
577
578 snapc = ci->i_snap_realm->cached_context;
579 vino = ceph_vino(inode);
580 req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout,
581 vino, pos, &len,
582 2,/*include a 'startsync' command*/
583 CEPH_OSD_OP_WRITE, flags, snapc,
584 ci->i_truncate_seq,
585 ci->i_truncate_size,
586 false);
587 if (IS_ERR(req)) {
588 ret = PTR_ERR(req);
589 break;
590 }
591
592 n = iov_iter_get_pages_alloc(from, &pages, len, &start);
593 if (unlikely(n < 0)) {
594 ret = n;
595 ceph_osdc_put_request(req);
596 break;
597 }
598
599 num_pages = (n + start + PAGE_SIZE - 1) / PAGE_SIZE;
600 /*
601 * throw out any page cache pages in this range. this
602 * may block.
603 */
604 truncate_inode_pages_range(inode->i_mapping, pos,
605 (pos+n) | (PAGE_CACHE_SIZE-1));
606 osd_req_op_extent_osd_data_pages(req, 0, pages, n, start,
607 false, false);
608
609 /* BUG_ON(vino.snap != CEPH_NOSNAP); */
610 ceph_osdc_build_request(req, pos, snapc, vino.snap, &mtime);
611
612 ret = ceph_osdc_start_request(&fsc->client->osdc, req, false);
613 if (!ret)
614 ret = ceph_osdc_wait_request(&fsc->client->osdc, req);
615
616 ceph_put_page_vector(pages, num_pages, false);
617
618 ceph_osdc_put_request(req);
619 if (ret)
620 break;
621 pos += n;
622 written += n;
623 iov_iter_advance(from, n);
624
625 if (pos > i_size_read(inode)) {
626 check_caps = ceph_inode_set_size(inode, pos);
627 if (check_caps)
628 ceph_check_caps(ceph_inode(inode),
629 CHECK_CAPS_AUTHONLY,
630 NULL);
631 }
632 }
633
634 if (ret != -EOLDSNAPC && written > 0) {
635 iocb->ki_pos = pos;
636 ret = written;
637 }
638 return ret;
639 }
640
641
642 /*
643 * Synchronous write, straight from __user pointer or user pages.
644 *
645 * If write spans object boundary, just do multiple writes. (For a
646 * correct atomic write, we should e.g. take write locks on all
647 * objects, rollback on failure, etc.)
648 */
649 static ssize_t ceph_sync_write(struct kiocb *iocb, struct iov_iter *from)
650 {
651 struct file *file = iocb->ki_filp;
652 struct inode *inode = file_inode(file);
653 struct ceph_inode_info *ci = ceph_inode(inode);
654 struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
655 struct ceph_snap_context *snapc;
656 struct ceph_vino vino;
657 struct ceph_osd_request *req;
658 struct page **pages;
659 u64 len;
660 int num_pages;
661 int written = 0;
662 int flags;
663 int check_caps = 0;
664 int ret;
665 struct timespec mtime = CURRENT_TIME;
666 loff_t pos = iocb->ki_pos;
667 size_t count = iov_iter_count(from);
668
669 if (ceph_snap(file_inode(file)) != CEPH_NOSNAP)
670 return -EROFS;
671
672 dout("sync_write on file %p %lld~%u\n", file, pos, (unsigned)count);
673
674 ret = filemap_write_and_wait_range(inode->i_mapping, pos, pos + count);
675 if (ret < 0)
676 return ret;
677
678 ret = invalidate_inode_pages2_range(inode->i_mapping,
679 pos >> PAGE_CACHE_SHIFT,
680 (pos + count) >> PAGE_CACHE_SHIFT);
681 if (ret < 0)
682 dout("invalidate_inode_pages2_range returned %d\n", ret);
683
684 flags = CEPH_OSD_FLAG_ORDERSNAP |
685 CEPH_OSD_FLAG_ONDISK |
686 CEPH_OSD_FLAG_WRITE |
687 CEPH_OSD_FLAG_ACK;
688
689 while ((len = iov_iter_count(from)) > 0) {
690 size_t left;
691 int n;
692
693 snapc = ci->i_snap_realm->cached_context;
694 vino = ceph_vino(inode);
695 req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout,
696 vino, pos, &len, 1,
697 CEPH_OSD_OP_WRITE, flags, snapc,
698 ci->i_truncate_seq,
699 ci->i_truncate_size,
700 false);
701 if (IS_ERR(req)) {
702 ret = PTR_ERR(req);
703 break;
704 }
705
706 /*
707 * write from beginning of first page,
708 * regardless of io alignment
709 */
710 num_pages = (len + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
711
712 pages = ceph_alloc_page_vector(num_pages, GFP_NOFS);
713 if (IS_ERR(pages)) {
714 ret = PTR_ERR(pages);
715 goto out;
716 }
717
718 left = len;
719 for (n = 0; n < num_pages; n++) {
720 size_t plen = min_t(size_t, left, PAGE_SIZE);
721 ret = copy_page_from_iter(pages[n], 0, plen, from);
722 if (ret != plen) {
723 ret = -EFAULT;
724 break;
725 }
726 left -= ret;
727 }
728
729 if (ret < 0) {
730 ceph_release_page_vector(pages, num_pages);
731 goto out;
732 }
733
734 /* get a second commit callback */
735 req->r_unsafe_callback = ceph_sync_write_unsafe;
736 req->r_inode = inode;
737
738 osd_req_op_extent_osd_data_pages(req, 0, pages, len, 0,
739 false, true);
740
741 /* BUG_ON(vino.snap != CEPH_NOSNAP); */
742 ceph_osdc_build_request(req, pos, snapc, vino.snap, &mtime);
743
744 ret = ceph_osdc_start_request(&fsc->client->osdc, req, false);
745 if (!ret)
746 ret = ceph_osdc_wait_request(&fsc->client->osdc, req);
747
748 out:
749 ceph_osdc_put_request(req);
750 if (ret == 0) {
751 pos += len;
752 written += len;
753
754 if (pos > i_size_read(inode)) {
755 check_caps = ceph_inode_set_size(inode, pos);
756 if (check_caps)
757 ceph_check_caps(ceph_inode(inode),
758 CHECK_CAPS_AUTHONLY,
759 NULL);
760 }
761 } else
762 break;
763 }
764
765 if (ret != -EOLDSNAPC && written > 0) {
766 ret = written;
767 iocb->ki_pos = pos;
768 }
769 return ret;
770 }
771
772 /*
773 * Wrap generic_file_aio_read with checks for cap bits on the inode.
774 * Atomically grab references, so that those bits are not released
775 * back to the MDS mid-read.
776 *
777 * Hmm, the sync read case isn't actually async... should it be?
778 */
779 static ssize_t ceph_read_iter(struct kiocb *iocb, struct iov_iter *to)
780 {
781 struct file *filp = iocb->ki_filp;
782 struct ceph_file_info *fi = filp->private_data;
783 size_t len = iocb->ki_nbytes;
784 struct inode *inode = file_inode(filp);
785 struct ceph_inode_info *ci = ceph_inode(inode);
786 ssize_t ret;
787 int want, got = 0;
788 int checkeof = 0, read = 0;
789
790 again:
791 dout("aio_read %p %llx.%llx %llu~%u trying to get caps on %p\n",
792 inode, ceph_vinop(inode), iocb->ki_pos, (unsigned)len, inode);
793
794 if (fi->fmode & CEPH_FILE_MODE_LAZY)
795 want = CEPH_CAP_FILE_CACHE | CEPH_CAP_FILE_LAZYIO;
796 else
797 want = CEPH_CAP_FILE_CACHE;
798 ret = ceph_get_caps(ci, CEPH_CAP_FILE_RD, want, &got, -1);
799 if (ret < 0)
800 return ret;
801
802 if ((got & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)) == 0 ||
803 (iocb->ki_filp->f_flags & O_DIRECT) ||
804 (fi->flags & CEPH_F_SYNC)) {
805
806 dout("aio_sync_read %p %llx.%llx %llu~%u got cap refs on %s\n",
807 inode, ceph_vinop(inode), iocb->ki_pos, (unsigned)len,
808 ceph_cap_string(got));
809
810 /* hmm, this isn't really async... */
811 ret = ceph_sync_read(iocb, to, &checkeof);
812 } else {
813 dout("aio_read %p %llx.%llx %llu~%u got cap refs on %s\n",
814 inode, ceph_vinop(inode), iocb->ki_pos, (unsigned)len,
815 ceph_cap_string(got));
816
817 ret = generic_file_read_iter(iocb, to);
818 }
819 dout("aio_read %p %llx.%llx dropping cap refs on %s = %d\n",
820 inode, ceph_vinop(inode), ceph_cap_string(got), (int)ret);
821 ceph_put_cap_refs(ci, got);
822
823 if (checkeof && ret >= 0) {
824 int statret = ceph_do_getattr(inode,
825 CEPH_STAT_CAP_SIZE);
826
827 /* hit EOF or hole? */
828 if (statret == 0 && iocb->ki_pos < inode->i_size &&
829 ret < len) {
830 dout("sync_read hit hole, ppos %lld < size %lld"
831 ", reading more\n", iocb->ki_pos,
832 inode->i_size);
833
834 iov_iter_advance(to, ret);
835 read += ret;
836 len -= ret;
837 checkeof = 0;
838 goto again;
839 }
840 }
841
842 if (ret >= 0)
843 ret += read;
844
845 return ret;
846 }
847
848 /*
849 * Take cap references to avoid releasing caps to MDS mid-write.
850 *
851 * If we are synchronous, and write with an old snap context, the OSD
852 * may return EOLDSNAPC. In that case, retry the write.. _after_
853 * dropping our cap refs and allowing the pending snap to logically
854 * complete _before_ this write occurs.
855 *
856 * If we are near ENOSPC, write synchronously.
857 */
858 static ssize_t ceph_write_iter(struct kiocb *iocb, struct iov_iter *from)
859 {
860 struct file *file = iocb->ki_filp;
861 struct ceph_file_info *fi = file->private_data;
862 struct inode *inode = file_inode(file);
863 struct ceph_inode_info *ci = ceph_inode(inode);
864 struct ceph_osd_client *osdc =
865 &ceph_sb_to_client(inode->i_sb)->client->osdc;
866 ssize_t count = iov_iter_count(from), written = 0;
867 int err, want, got;
868 loff_t pos = iocb->ki_pos;
869
870 if (ceph_snap(inode) != CEPH_NOSNAP)
871 return -EROFS;
872
873 mutex_lock(&inode->i_mutex);
874
875 /* We can write back this queue in page reclaim */
876 current->backing_dev_info = file->f_mapping->backing_dev_info;
877
878 err = generic_write_checks(file, &pos, &count, S_ISBLK(inode->i_mode));
879 if (err)
880 goto out;
881
882 if (count == 0)
883 goto out;
884 iov_iter_truncate(from, count);
885
886 err = file_remove_suid(file);
887 if (err)
888 goto out;
889
890 err = file_update_time(file);
891 if (err)
892 goto out;
893
894 retry_snap:
895 if (ceph_osdmap_flag(osdc->osdmap, CEPH_OSDMAP_FULL)) {
896 err = -ENOSPC;
897 goto out;
898 }
899
900 dout("aio_write %p %llx.%llx %llu~%zd getting caps. i_size %llu\n",
901 inode, ceph_vinop(inode), pos, count, inode->i_size);
902 if (fi->fmode & CEPH_FILE_MODE_LAZY)
903 want = CEPH_CAP_FILE_BUFFER | CEPH_CAP_FILE_LAZYIO;
904 else
905 want = CEPH_CAP_FILE_BUFFER;
906 got = 0;
907 err = ceph_get_caps(ci, CEPH_CAP_FILE_WR, want, &got, pos + count);
908 if (err < 0)
909 goto out;
910
911 dout("aio_write %p %llx.%llx %llu~%zd got cap refs on %s\n",
912 inode, ceph_vinop(inode), pos, count, ceph_cap_string(got));
913
914 if ((got & (CEPH_CAP_FILE_BUFFER|CEPH_CAP_FILE_LAZYIO)) == 0 ||
915 (file->f_flags & O_DIRECT) || (fi->flags & CEPH_F_SYNC)) {
916 struct iov_iter data;
917 mutex_unlock(&inode->i_mutex);
918 /* we might need to revert back to that point */
919 data = *from;
920 if (file->f_flags & O_DIRECT)
921 written = ceph_sync_direct_write(iocb, &data);
922 else
923 written = ceph_sync_write(iocb, &data);
924 if (written == -EOLDSNAPC) {
925 dout("aio_write %p %llx.%llx %llu~%u"
926 "got EOLDSNAPC, retrying\n",
927 inode, ceph_vinop(inode),
928 pos, (unsigned)count);
929 mutex_lock(&inode->i_mutex);
930 goto retry_snap;
931 }
932 if (written > 0)
933 iov_iter_advance(from, written);
934 } else {
935 loff_t old_size = inode->i_size;
936 /*
937 * No need to acquire the i_truncate_mutex. Because
938 * the MDS revokes Fwb caps before sending truncate
939 * message to us. We can't get Fwb cap while there
940 * are pending vmtruncate. So write and vmtruncate
941 * can not run at the same time
942 */
943 written = generic_perform_write(file, from, pos);
944 if (likely(written >= 0))
945 iocb->ki_pos = pos + written;
946 if (inode->i_size > old_size)
947 ceph_fscache_update_objectsize(inode);
948 mutex_unlock(&inode->i_mutex);
949 }
950
951 if (written >= 0) {
952 int dirty;
953 spin_lock(&ci->i_ceph_lock);
954 dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_FILE_WR);
955 spin_unlock(&ci->i_ceph_lock);
956 if (dirty)
957 __mark_inode_dirty(inode, dirty);
958 }
959
960 dout("aio_write %p %llx.%llx %llu~%u dropping cap refs on %s\n",
961 inode, ceph_vinop(inode), pos, (unsigned)count,
962 ceph_cap_string(got));
963 ceph_put_cap_refs(ci, got);
964
965 if (written >= 0 &&
966 ((file->f_flags & O_SYNC) || IS_SYNC(file->f_mapping->host) ||
967 ceph_osdmap_flag(osdc->osdmap, CEPH_OSDMAP_NEARFULL))) {
968 err = vfs_fsync_range(file, pos, pos + written - 1, 1);
969 if (err < 0)
970 written = err;
971 }
972
973 goto out_unlocked;
974
975 out:
976 mutex_unlock(&inode->i_mutex);
977 out_unlocked:
978 current->backing_dev_info = NULL;
979 return written ? written : err;
980 }
981
982 /*
983 * llseek. be sure to verify file size on SEEK_END.
984 */
985 static loff_t ceph_llseek(struct file *file, loff_t offset, int whence)
986 {
987 struct inode *inode = file->f_mapping->host;
988 int ret;
989
990 mutex_lock(&inode->i_mutex);
991
992 if (whence == SEEK_END || whence == SEEK_DATA || whence == SEEK_HOLE) {
993 ret = ceph_do_getattr(inode, CEPH_STAT_CAP_SIZE);
994 if (ret < 0) {
995 offset = ret;
996 goto out;
997 }
998 }
999
1000 switch (whence) {
1001 case SEEK_END:
1002 offset += inode->i_size;
1003 break;
1004 case SEEK_CUR:
1005 /*
1006 * Here we special-case the lseek(fd, 0, SEEK_CUR)
1007 * position-querying operation. Avoid rewriting the "same"
1008 * f_pos value back to the file because a concurrent read(),
1009 * write() or lseek() might have altered it
1010 */
1011 if (offset == 0) {
1012 offset = file->f_pos;
1013 goto out;
1014 }
1015 offset += file->f_pos;
1016 break;
1017 case SEEK_DATA:
1018 if (offset >= inode->i_size) {
1019 ret = -ENXIO;
1020 goto out;
1021 }
1022 break;
1023 case SEEK_HOLE:
1024 if (offset >= inode->i_size) {
1025 ret = -ENXIO;
1026 goto out;
1027 }
1028 offset = inode->i_size;
1029 break;
1030 }
1031
1032 offset = vfs_setpos(file, offset, inode->i_sb->s_maxbytes);
1033
1034 out:
1035 mutex_unlock(&inode->i_mutex);
1036 return offset;
1037 }
1038
1039 static inline void ceph_zero_partial_page(
1040 struct inode *inode, loff_t offset, unsigned size)
1041 {
1042 struct page *page;
1043 pgoff_t index = offset >> PAGE_CACHE_SHIFT;
1044
1045 page = find_lock_page(inode->i_mapping, index);
1046 if (page) {
1047 wait_on_page_writeback(page);
1048 zero_user(page, offset & (PAGE_CACHE_SIZE - 1), size);
1049 unlock_page(page);
1050 page_cache_release(page);
1051 }
1052 }
1053
1054 static void ceph_zero_pagecache_range(struct inode *inode, loff_t offset,
1055 loff_t length)
1056 {
1057 loff_t nearly = round_up(offset, PAGE_CACHE_SIZE);
1058 if (offset < nearly) {
1059 loff_t size = nearly - offset;
1060 if (length < size)
1061 size = length;
1062 ceph_zero_partial_page(inode, offset, size);
1063 offset += size;
1064 length -= size;
1065 }
1066 if (length >= PAGE_CACHE_SIZE) {
1067 loff_t size = round_down(length, PAGE_CACHE_SIZE);
1068 truncate_pagecache_range(inode, offset, offset + size - 1);
1069 offset += size;
1070 length -= size;
1071 }
1072 if (length)
1073 ceph_zero_partial_page(inode, offset, length);
1074 }
1075
1076 static int ceph_zero_partial_object(struct inode *inode,
1077 loff_t offset, loff_t *length)
1078 {
1079 struct ceph_inode_info *ci = ceph_inode(inode);
1080 struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
1081 struct ceph_osd_request *req;
1082 int ret = 0;
1083 loff_t zero = 0;
1084 int op;
1085
1086 if (!length) {
1087 op = offset ? CEPH_OSD_OP_DELETE : CEPH_OSD_OP_TRUNCATE;
1088 length = &zero;
1089 } else {
1090 op = CEPH_OSD_OP_ZERO;
1091 }
1092
1093 req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout,
1094 ceph_vino(inode),
1095 offset, length,
1096 1, op,
1097 CEPH_OSD_FLAG_WRITE |
1098 CEPH_OSD_FLAG_ONDISK,
1099 NULL, 0, 0, false);
1100 if (IS_ERR(req)) {
1101 ret = PTR_ERR(req);
1102 goto out;
1103 }
1104
1105 ceph_osdc_build_request(req, offset, NULL, ceph_vino(inode).snap,
1106 &inode->i_mtime);
1107
1108 ret = ceph_osdc_start_request(&fsc->client->osdc, req, false);
1109 if (!ret) {
1110 ret = ceph_osdc_wait_request(&fsc->client->osdc, req);
1111 if (ret == -ENOENT)
1112 ret = 0;
1113 }
1114 ceph_osdc_put_request(req);
1115
1116 out:
1117 return ret;
1118 }
1119
1120 static int ceph_zero_objects(struct inode *inode, loff_t offset, loff_t length)
1121 {
1122 int ret = 0;
1123 struct ceph_inode_info *ci = ceph_inode(inode);
1124 s32 stripe_unit = ceph_file_layout_su(ci->i_layout);
1125 s32 stripe_count = ceph_file_layout_stripe_count(ci->i_layout);
1126 s32 object_size = ceph_file_layout_object_size(ci->i_layout);
1127 u64 object_set_size = object_size * stripe_count;
1128 u64 nearly, t;
1129
1130 /* round offset up to next period boundary */
1131 nearly = offset + object_set_size - 1;
1132 t = nearly;
1133 nearly -= do_div(t, object_set_size);
1134
1135 while (length && offset < nearly) {
1136 loff_t size = length;
1137 ret = ceph_zero_partial_object(inode, offset, &size);
1138 if (ret < 0)
1139 return ret;
1140 offset += size;
1141 length -= size;
1142 }
1143 while (length >= object_set_size) {
1144 int i;
1145 loff_t pos = offset;
1146 for (i = 0; i < stripe_count; ++i) {
1147 ret = ceph_zero_partial_object(inode, pos, NULL);
1148 if (ret < 0)
1149 return ret;
1150 pos += stripe_unit;
1151 }
1152 offset += object_set_size;
1153 length -= object_set_size;
1154 }
1155 while (length) {
1156 loff_t size = length;
1157 ret = ceph_zero_partial_object(inode, offset, &size);
1158 if (ret < 0)
1159 return ret;
1160 offset += size;
1161 length -= size;
1162 }
1163 return ret;
1164 }
1165
1166 static long ceph_fallocate(struct file *file, int mode,
1167 loff_t offset, loff_t length)
1168 {
1169 struct ceph_file_info *fi = file->private_data;
1170 struct inode *inode = file_inode(file);
1171 struct ceph_inode_info *ci = ceph_inode(inode);
1172 struct ceph_osd_client *osdc =
1173 &ceph_inode_to_client(inode)->client->osdc;
1174 int want, got = 0;
1175 int dirty;
1176 int ret = 0;
1177 loff_t endoff = 0;
1178 loff_t size;
1179
1180 if (!S_ISREG(inode->i_mode))
1181 return -EOPNOTSUPP;
1182
1183 mutex_lock(&inode->i_mutex);
1184
1185 if (ceph_snap(inode) != CEPH_NOSNAP) {
1186 ret = -EROFS;
1187 goto unlock;
1188 }
1189
1190 if (ceph_osdmap_flag(osdc->osdmap, CEPH_OSDMAP_FULL) &&
1191 !(mode & FALLOC_FL_PUNCH_HOLE)) {
1192 ret = -ENOSPC;
1193 goto unlock;
1194 }
1195
1196 size = i_size_read(inode);
1197 if (!(mode & FALLOC_FL_KEEP_SIZE))
1198 endoff = offset + length;
1199
1200 if (fi->fmode & CEPH_FILE_MODE_LAZY)
1201 want = CEPH_CAP_FILE_BUFFER | CEPH_CAP_FILE_LAZYIO;
1202 else
1203 want = CEPH_CAP_FILE_BUFFER;
1204
1205 ret = ceph_get_caps(ci, CEPH_CAP_FILE_WR, want, &got, endoff);
1206 if (ret < 0)
1207 goto unlock;
1208
1209 if (mode & FALLOC_FL_PUNCH_HOLE) {
1210 if (offset < size)
1211 ceph_zero_pagecache_range(inode, offset, length);
1212 ret = ceph_zero_objects(inode, offset, length);
1213 } else if (endoff > size) {
1214 truncate_pagecache_range(inode, size, -1);
1215 if (ceph_inode_set_size(inode, endoff))
1216 ceph_check_caps(ceph_inode(inode),
1217 CHECK_CAPS_AUTHONLY, NULL);
1218 }
1219
1220 if (!ret) {
1221 spin_lock(&ci->i_ceph_lock);
1222 dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_FILE_WR);
1223 spin_unlock(&ci->i_ceph_lock);
1224 if (dirty)
1225 __mark_inode_dirty(inode, dirty);
1226 }
1227
1228 ceph_put_cap_refs(ci, got);
1229 unlock:
1230 mutex_unlock(&inode->i_mutex);
1231 return ret;
1232 }
1233
1234 const struct file_operations ceph_file_fops = {
1235 .open = ceph_open,
1236 .release = ceph_release,
1237 .llseek = ceph_llseek,
1238 .read = new_sync_read,
1239 .write = new_sync_write,
1240 .read_iter = ceph_read_iter,
1241 .write_iter = ceph_write_iter,
1242 .mmap = ceph_mmap,
1243 .fsync = ceph_fsync,
1244 .lock = ceph_lock,
1245 .flock = ceph_flock,
1246 .splice_read = generic_file_splice_read,
1247 .splice_write = iter_file_splice_write,
1248 .unlocked_ioctl = ceph_ioctl,
1249 .compat_ioctl = ceph_ioctl,
1250 .fallocate = ceph_fallocate,
1251 };
1252
Linux with added FPC-III support