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Merge branch 'drm-fixes' of git://people.freedesktop.org/~airlied/linux
[deliverable/linux.git] / fs / ceph / file.c
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_path.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 struct ceph_acls_info acls = {};
239 int err;
240
241 dout("atomic_open %p dentry %p '%pd' %s flags %d mode 0%o\n",
242 dir, dentry, dentry,
243 d_unhashed(dentry) ? "unhashed" : "hashed", flags, mode);
244
245 if (dentry->d_name.len > NAME_MAX)
246 return -ENAMETOOLONG;
247
248 err = ceph_init_dentry(dentry);
249 if (err < 0)
250 return err;
251
252 if (flags & O_CREAT) {
253 err = ceph_pre_init_acls(dir, &mode, &acls);
254 if (err < 0)
255 return err;
256 }
257
258 /* do the open */
259 req = prepare_open_request(dir->i_sb, flags, mode);
260 if (IS_ERR(req)) {
261 err = PTR_ERR(req);
262 goto out_acl;
263 }
264 req->r_dentry = dget(dentry);
265 req->r_num_caps = 2;
266 if (flags & O_CREAT) {
267 req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
268 req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
269 if (acls.pagelist) {
270 req->r_pagelist = acls.pagelist;
271 acls.pagelist = NULL;
272 }
273 }
274 req->r_locked_dir = dir; /* caller holds dir->i_mutex */
275 err = ceph_mdsc_do_request(mdsc,
276 (flags & (O_CREAT|O_TRUNC)) ? dir : NULL,
277 req);
278 if (err)
279 goto out_req;
280
281 err = ceph_handle_snapdir(req, dentry, err);
282 if (err == 0 && (flags & O_CREAT) && !req->r_reply_info.head->is_dentry)
283 err = ceph_handle_notrace_create(dir, dentry);
284
285 if (d_unhashed(dentry)) {
286 dn = ceph_finish_lookup(req, dentry, err);
287 if (IS_ERR(dn))
288 err = PTR_ERR(dn);
289 } else {
290 /* we were given a hashed negative dentry */
291 dn = NULL;
292 }
293 if (err)
294 goto out_req;
295 if (dn || dentry->d_inode == NULL || S_ISLNK(dentry->d_inode->i_mode)) {
296 /* make vfs retry on splice, ENOENT, or symlink */
297 dout("atomic_open finish_no_open on dn %p\n", dn);
298 err = finish_no_open(file, dn);
299 } else {
300 dout("atomic_open finish_open on dn %p\n", dn);
301 if (req->r_op == CEPH_MDS_OP_CREATE && req->r_reply_info.has_create_ino) {
302 ceph_init_inode_acls(dentry->d_inode, &acls);
303 *opened |= FILE_CREATED;
304 }
305 err = finish_open(file, dentry, ceph_open, opened);
306 }
307 out_req:
308 if (!req->r_err && req->r_target_inode)
309 ceph_put_fmode(ceph_inode(req->r_target_inode), req->r_fmode);
310 ceph_mdsc_put_request(req);
311 out_acl:
312 ceph_release_acls_info(&acls);
313 dout("atomic_open result=%d\n", err);
314 return err;
315 }
316
317 int ceph_release(struct inode *inode, struct file *file)
318 {
319 struct ceph_inode_info *ci = ceph_inode(inode);
320 struct ceph_file_info *cf = file->private_data;
321
322 dout("release inode %p file %p\n", inode, file);
323 ceph_put_fmode(ci, cf->fmode);
324 if (cf->last_readdir)
325 ceph_mdsc_put_request(cf->last_readdir);
326 kfree(cf->last_name);
327 kfree(cf->dir_info);
328 dput(cf->dentry);
329 kmem_cache_free(ceph_file_cachep, cf);
330
331 /* wake up anyone waiting for caps on this inode */
332 wake_up_all(&ci->i_cap_wq);
333 return 0;
334 }
335
336 enum {
337 CHECK_EOF = 1,
338 READ_INLINE = 2,
339 };
340
341 /*
342 * Read a range of bytes striped over one or more objects. Iterate over
343 * objects we stripe over. (That's not atomic, but good enough for now.)
344 *
345 * If we get a short result from the OSD, check against i_size; we need to
346 * only return a short read to the caller if we hit EOF.
347 */
348 static int striped_read(struct inode *inode,
349 u64 off, u64 len,
350 struct page **pages, int num_pages,
351 int *checkeof, bool o_direct,
352 unsigned long buf_align)
353 {
354 struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
355 struct ceph_inode_info *ci = ceph_inode(inode);
356 u64 pos, this_len, left;
357 int io_align, page_align;
358 int pages_left;
359 int read;
360 struct page **page_pos;
361 int ret;
362 bool hit_stripe, was_short;
363
364 /*
365 * we may need to do multiple reads. not atomic, unfortunately.
366 */
367 pos = off;
368 left = len;
369 page_pos = pages;
370 pages_left = num_pages;
371 read = 0;
372 io_align = off & ~PAGE_MASK;
373
374 more:
375 if (o_direct)
376 page_align = (pos - io_align + buf_align) & ~PAGE_MASK;
377 else
378 page_align = pos & ~PAGE_MASK;
379 this_len = left;
380 ret = ceph_osdc_readpages(&fsc->client->osdc, ceph_vino(inode),
381 &ci->i_layout, pos, &this_len,
382 ci->i_truncate_seq,
383 ci->i_truncate_size,
384 page_pos, pages_left, page_align);
385 if (ret == -ENOENT)
386 ret = 0;
387 hit_stripe = this_len < left;
388 was_short = ret >= 0 && ret < this_len;
389 dout("striped_read %llu~%llu (read %u) got %d%s%s\n", pos, left, read,
390 ret, hit_stripe ? " HITSTRIPE" : "", was_short ? " SHORT" : "");
391
392 if (ret >= 0) {
393 int didpages;
394 if (was_short && (pos + ret < inode->i_size)) {
395 u64 tmp = min(this_len - ret,
396 inode->i_size - pos - ret);
397 dout(" zero gap %llu to %llu\n",
398 pos + ret, pos + ret + tmp);
399 ceph_zero_page_vector_range(page_align + read + ret,
400 tmp, pages);
401 ret += tmp;
402 }
403
404 didpages = (page_align + ret) >> PAGE_CACHE_SHIFT;
405 pos += ret;
406 read = pos - off;
407 left -= ret;
408 page_pos += didpages;
409 pages_left -= didpages;
410
411 /* hit stripe and need continue*/
412 if (left && hit_stripe && pos < inode->i_size)
413 goto more;
414 }
415
416 if (read > 0) {
417 ret = read;
418 /* did we bounce off eof? */
419 if (pos + left > inode->i_size)
420 *checkeof = CHECK_EOF;
421 }
422
423 dout("striped_read returns %d\n", ret);
424 return ret;
425 }
426
427 /*
428 * Completely synchronous read and write methods. Direct from __user
429 * buffer to osd, or directly to user pages (if O_DIRECT).
430 *
431 * If the read spans object boundary, just do multiple reads.
432 */
433 static ssize_t ceph_sync_read(struct kiocb *iocb, struct iov_iter *i,
434 int *checkeof)
435 {
436 struct file *file = iocb->ki_filp;
437 struct inode *inode = file_inode(file);
438 struct page **pages;
439 u64 off = iocb->ki_pos;
440 int num_pages, ret;
441 size_t len = iov_iter_count(i);
442
443 dout("sync_read on file %p %llu~%u %s\n", file, off,
444 (unsigned)len,
445 (file->f_flags & O_DIRECT) ? "O_DIRECT" : "");
446
447 if (!len)
448 return 0;
449 /*
450 * flush any page cache pages in this range. this
451 * will make concurrent normal and sync io slow,
452 * but it will at least behave sensibly when they are
453 * in sequence.
454 */
455 ret = filemap_write_and_wait_range(inode->i_mapping, off,
456 off + len);
457 if (ret < 0)
458 return ret;
459
460 if (file->f_flags & O_DIRECT) {
461 while (iov_iter_count(i)) {
462 size_t start;
463 ssize_t n;
464
465 n = iov_iter_get_pages_alloc(i, &pages, INT_MAX, &start);
466 if (n < 0)
467 return n;
468
469 num_pages = (n + start + PAGE_SIZE - 1) / PAGE_SIZE;
470
471 ret = striped_read(inode, off, n,
472 pages, num_pages, checkeof,
473 1, start);
474
475 ceph_put_page_vector(pages, num_pages, true);
476
477 if (ret <= 0)
478 break;
479 off += ret;
480 iov_iter_advance(i, ret);
481 if (ret < n)
482 break;
483 }
484 } else {
485 num_pages = calc_pages_for(off, len);
486 pages = ceph_alloc_page_vector(num_pages, GFP_NOFS);
487 if (IS_ERR(pages))
488 return PTR_ERR(pages);
489 ret = striped_read(inode, off, len, pages,
490 num_pages, checkeof, 0, 0);
491 if (ret > 0) {
492 int l, k = 0;
493 size_t left = ret;
494
495 while (left) {
496 size_t page_off = off & ~PAGE_MASK;
497 size_t copy = min_t(size_t,
498 PAGE_SIZE - page_off, left);
499 l = copy_page_to_iter(pages[k++], page_off,
500 copy, i);
501 off += l;
502 left -= l;
503 if (l < copy)
504 break;
505 }
506 }
507 ceph_release_page_vector(pages, num_pages);
508 }
509
510 if (off > iocb->ki_pos) {
511 ret = off - iocb->ki_pos;
512 iocb->ki_pos = off;
513 }
514
515 dout("sync_read result %d\n", ret);
516 return ret;
517 }
518
519 /*
520 * Write commit request unsafe callback, called to tell us when a
521 * request is unsafe (that is, in flight--has been handed to the
522 * messenger to send to its target osd). It is called again when
523 * we've received a response message indicating the request is
524 * "safe" (its CEPH_OSD_FLAG_ONDISK flag is set), or when a request
525 * is completed early (and unsuccessfully) due to a timeout or
526 * interrupt.
527 *
528 * This is used if we requested both an ACK and ONDISK commit reply
529 * from the OSD.
530 */
531 static void ceph_sync_write_unsafe(struct ceph_osd_request *req, bool unsafe)
532 {
533 struct ceph_inode_info *ci = ceph_inode(req->r_inode);
534
535 dout("%s %p tid %llu %ssafe\n", __func__, req, req->r_tid,
536 unsafe ? "un" : "");
537 if (unsafe) {
538 ceph_get_cap_refs(ci, CEPH_CAP_FILE_WR);
539 spin_lock(&ci->i_unsafe_lock);
540 list_add_tail(&req->r_unsafe_item,
541 &ci->i_unsafe_writes);
542 spin_unlock(&ci->i_unsafe_lock);
543 } else {
544 spin_lock(&ci->i_unsafe_lock);
545 list_del_init(&req->r_unsafe_item);
546 spin_unlock(&ci->i_unsafe_lock);
547 ceph_put_cap_refs(ci, CEPH_CAP_FILE_WR);
548 }
549 }
550
551
552 /*
553 * Synchronous write, straight from __user pointer or user pages.
554 *
555 * If write spans object boundary, just do multiple writes. (For a
556 * correct atomic write, we should e.g. take write locks on all
557 * objects, rollback on failure, etc.)
558 */
559 static ssize_t
560 ceph_sync_direct_write(struct kiocb *iocb, struct iov_iter *from, loff_t pos)
561 {
562 struct file *file = iocb->ki_filp;
563 struct inode *inode = file_inode(file);
564 struct ceph_inode_info *ci = ceph_inode(inode);
565 struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
566 struct ceph_snap_context *snapc;
567 struct ceph_vino vino;
568 struct ceph_osd_request *req;
569 struct page **pages;
570 int num_pages;
571 int written = 0;
572 int flags;
573 int check_caps = 0;
574 int ret;
575 struct timespec mtime = CURRENT_TIME;
576 size_t count = iov_iter_count(from);
577
578 if (ceph_snap(file_inode(file)) != CEPH_NOSNAP)
579 return -EROFS;
580
581 dout("sync_direct_write on file %p %lld~%u\n", file, pos,
582 (unsigned)count);
583
584 ret = filemap_write_and_wait_range(inode->i_mapping, pos, pos + count);
585 if (ret < 0)
586 return ret;
587
588 ret = invalidate_inode_pages2_range(inode->i_mapping,
589 pos >> PAGE_CACHE_SHIFT,
590 (pos + count) >> PAGE_CACHE_SHIFT);
591 if (ret < 0)
592 dout("invalidate_inode_pages2_range returned %d\n", ret);
593
594 flags = CEPH_OSD_FLAG_ORDERSNAP |
595 CEPH_OSD_FLAG_ONDISK |
596 CEPH_OSD_FLAG_WRITE;
597
598 while (iov_iter_count(from) > 0) {
599 u64 len = iov_iter_single_seg_count(from);
600 size_t start;
601 ssize_t n;
602
603 snapc = ci->i_snap_realm->cached_context;
604 vino = ceph_vino(inode);
605 req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout,
606 vino, pos, &len, 0,
607 2,/*include a 'startsync' command*/
608 CEPH_OSD_OP_WRITE, flags, snapc,
609 ci->i_truncate_seq,
610 ci->i_truncate_size,
611 false);
612 if (IS_ERR(req)) {
613 ret = PTR_ERR(req);
614 break;
615 }
616
617 osd_req_op_init(req, 1, CEPH_OSD_OP_STARTSYNC);
618
619 n = iov_iter_get_pages_alloc(from, &pages, len, &start);
620 if (unlikely(n < 0)) {
621 ret = n;
622 ceph_osdc_put_request(req);
623 break;
624 }
625
626 num_pages = (n + start + PAGE_SIZE - 1) / PAGE_SIZE;
627 /*
628 * throw out any page cache pages in this range. this
629 * may block.
630 */
631 truncate_inode_pages_range(inode->i_mapping, pos,
632 (pos+n) | (PAGE_CACHE_SIZE-1));
633 osd_req_op_extent_osd_data_pages(req, 0, pages, n, start,
634 false, false);
635
636 /* BUG_ON(vino.snap != CEPH_NOSNAP); */
637 ceph_osdc_build_request(req, pos, snapc, vino.snap, &mtime);
638
639 ret = ceph_osdc_start_request(&fsc->client->osdc, req, false);
640 if (!ret)
641 ret = ceph_osdc_wait_request(&fsc->client->osdc, req);
642
643 ceph_put_page_vector(pages, num_pages, false);
644
645 ceph_osdc_put_request(req);
646 if (ret)
647 break;
648 pos += n;
649 written += n;
650 iov_iter_advance(from, n);
651
652 if (pos > i_size_read(inode)) {
653 check_caps = ceph_inode_set_size(inode, pos);
654 if (check_caps)
655 ceph_check_caps(ceph_inode(inode),
656 CHECK_CAPS_AUTHONLY,
657 NULL);
658 }
659 }
660
661 if (ret != -EOLDSNAPC && written > 0) {
662 iocb->ki_pos = pos;
663 ret = written;
664 }
665 return ret;
666 }
667
668
669 /*
670 * Synchronous write, straight from __user pointer or user pages.
671 *
672 * If write spans object boundary, just do multiple writes. (For a
673 * correct atomic write, we should e.g. take write locks on all
674 * objects, rollback on failure, etc.)
675 */
676 static ssize_t
677 ceph_sync_write(struct kiocb *iocb, struct iov_iter *from, loff_t pos)
678 {
679 struct file *file = iocb->ki_filp;
680 struct inode *inode = file_inode(file);
681 struct ceph_inode_info *ci = ceph_inode(inode);
682 struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
683 struct ceph_snap_context *snapc;
684 struct ceph_vino vino;
685 struct ceph_osd_request *req;
686 struct page **pages;
687 u64 len;
688 int num_pages;
689 int written = 0;
690 int flags;
691 int check_caps = 0;
692 int ret;
693 struct timespec mtime = CURRENT_TIME;
694 size_t count = iov_iter_count(from);
695
696 if (ceph_snap(file_inode(file)) != CEPH_NOSNAP)
697 return -EROFS;
698
699 dout("sync_write on file %p %lld~%u\n", file, pos, (unsigned)count);
700
701 ret = filemap_write_and_wait_range(inode->i_mapping, pos, pos + count);
702 if (ret < 0)
703 return ret;
704
705 ret = invalidate_inode_pages2_range(inode->i_mapping,
706 pos >> PAGE_CACHE_SHIFT,
707 (pos + count) >> PAGE_CACHE_SHIFT);
708 if (ret < 0)
709 dout("invalidate_inode_pages2_range returned %d\n", ret);
710
711 flags = CEPH_OSD_FLAG_ORDERSNAP |
712 CEPH_OSD_FLAG_ONDISK |
713 CEPH_OSD_FLAG_WRITE |
714 CEPH_OSD_FLAG_ACK;
715
716 while ((len = iov_iter_count(from)) > 0) {
717 size_t left;
718 int n;
719
720 snapc = ci->i_snap_realm->cached_context;
721 vino = ceph_vino(inode);
722 req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout,
723 vino, pos, &len, 0, 1,
724 CEPH_OSD_OP_WRITE, flags, snapc,
725 ci->i_truncate_seq,
726 ci->i_truncate_size,
727 false);
728 if (IS_ERR(req)) {
729 ret = PTR_ERR(req);
730 break;
731 }
732
733 /*
734 * write from beginning of first page,
735 * regardless of io alignment
736 */
737 num_pages = (len + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
738
739 pages = ceph_alloc_page_vector(num_pages, GFP_NOFS);
740 if (IS_ERR(pages)) {
741 ret = PTR_ERR(pages);
742 goto out;
743 }
744
745 left = len;
746 for (n = 0; n < num_pages; n++) {
747 size_t plen = min_t(size_t, left, PAGE_SIZE);
748 ret = copy_page_from_iter(pages[n], 0, plen, from);
749 if (ret != plen) {
750 ret = -EFAULT;
751 break;
752 }
753 left -= ret;
754 }
755
756 if (ret < 0) {
757 ceph_release_page_vector(pages, num_pages);
758 goto out;
759 }
760
761 /* get a second commit callback */
762 req->r_unsafe_callback = ceph_sync_write_unsafe;
763 req->r_inode = inode;
764
765 osd_req_op_extent_osd_data_pages(req, 0, pages, len, 0,
766 false, true);
767
768 /* BUG_ON(vino.snap != CEPH_NOSNAP); */
769 ceph_osdc_build_request(req, pos, snapc, vino.snap, &mtime);
770
771 ret = ceph_osdc_start_request(&fsc->client->osdc, req, false);
772 if (!ret)
773 ret = ceph_osdc_wait_request(&fsc->client->osdc, req);
774
775 out:
776 ceph_osdc_put_request(req);
777 if (ret == 0) {
778 pos += len;
779 written += len;
780
781 if (pos > i_size_read(inode)) {
782 check_caps = ceph_inode_set_size(inode, pos);
783 if (check_caps)
784 ceph_check_caps(ceph_inode(inode),
785 CHECK_CAPS_AUTHONLY,
786 NULL);
787 }
788 } else
789 break;
790 }
791
792 if (ret != -EOLDSNAPC && written > 0) {
793 ret = written;
794 iocb->ki_pos = pos;
795 }
796 return ret;
797 }
798
799 /*
800 * Wrap generic_file_aio_read with checks for cap bits on the inode.
801 * Atomically grab references, so that those bits are not released
802 * back to the MDS mid-read.
803 *
804 * Hmm, the sync read case isn't actually async... should it be?
805 */
806 static ssize_t ceph_read_iter(struct kiocb *iocb, struct iov_iter *to)
807 {
808 struct file *filp = iocb->ki_filp;
809 struct ceph_file_info *fi = filp->private_data;
810 size_t len = iocb->ki_nbytes;
811 struct inode *inode = file_inode(filp);
812 struct ceph_inode_info *ci = ceph_inode(inode);
813 struct page *pinned_page = NULL;
814 ssize_t ret;
815 int want, got = 0;
816 int retry_op = 0, read = 0;
817
818 again:
819 dout("aio_read %p %llx.%llx %llu~%u trying to get caps on %p\n",
820 inode, ceph_vinop(inode), iocb->ki_pos, (unsigned)len, inode);
821
822 if (fi->fmode & CEPH_FILE_MODE_LAZY)
823 want = CEPH_CAP_FILE_CACHE | CEPH_CAP_FILE_LAZYIO;
824 else
825 want = CEPH_CAP_FILE_CACHE;
826 ret = ceph_get_caps(ci, CEPH_CAP_FILE_RD, want, -1, &got, &pinned_page);
827 if (ret < 0)
828 return ret;
829
830 if ((got & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)) == 0 ||
831 (iocb->ki_filp->f_flags & O_DIRECT) ||
832 (fi->flags & CEPH_F_SYNC)) {
833
834 dout("aio_sync_read %p %llx.%llx %llu~%u got cap refs on %s\n",
835 inode, ceph_vinop(inode), iocb->ki_pos, (unsigned)len,
836 ceph_cap_string(got));
837
838 if (ci->i_inline_version == CEPH_INLINE_NONE) {
839 /* hmm, this isn't really async... */
840 ret = ceph_sync_read(iocb, to, &retry_op);
841 } else {
842 retry_op = READ_INLINE;
843 }
844 } else {
845 dout("aio_read %p %llx.%llx %llu~%u got cap refs on %s\n",
846 inode, ceph_vinop(inode), iocb->ki_pos, (unsigned)len,
847 ceph_cap_string(got));
848
849 ret = generic_file_read_iter(iocb, to);
850 }
851 dout("aio_read %p %llx.%llx dropping cap refs on %s = %d\n",
852 inode, ceph_vinop(inode), ceph_cap_string(got), (int)ret);
853 if (pinned_page) {
854 page_cache_release(pinned_page);
855 pinned_page = NULL;
856 }
857 ceph_put_cap_refs(ci, got);
858 if (retry_op && ret >= 0) {
859 int statret;
860 struct page *page = NULL;
861 loff_t i_size;
862 if (retry_op == READ_INLINE) {
863 page = __page_cache_alloc(GFP_NOFS);
864 if (!page)
865 return -ENOMEM;
866 }
867
868 statret = __ceph_do_getattr(inode, page,
869 CEPH_STAT_CAP_INLINE_DATA, !!page);
870 if (statret < 0) {
871 __free_page(page);
872 if (statret == -ENODATA) {
873 BUG_ON(retry_op != READ_INLINE);
874 goto again;
875 }
876 return statret;
877 }
878
879 i_size = i_size_read(inode);
880 if (retry_op == READ_INLINE) {
881 /* does not support inline data > PAGE_SIZE */
882 if (i_size > PAGE_CACHE_SIZE) {
883 ret = -EIO;
884 } else if (iocb->ki_pos < i_size) {
885 loff_t end = min_t(loff_t, i_size,
886 iocb->ki_pos + len);
887 if (statret < end)
888 zero_user_segment(page, statret, end);
889 ret = copy_page_to_iter(page,
890 iocb->ki_pos & ~PAGE_MASK,
891 end - iocb->ki_pos, to);
892 iocb->ki_pos += ret;
893 } else {
894 ret = 0;
895 }
896 __free_pages(page, 0);
897 return ret;
898 }
899
900 /* hit EOF or hole? */
901 if (retry_op == CHECK_EOF && iocb->ki_pos < i_size &&
902 ret < len) {
903 dout("sync_read hit hole, ppos %lld < size %lld"
904 ", reading more\n", iocb->ki_pos,
905 inode->i_size);
906
907 read += ret;
908 len -= ret;
909 retry_op = 0;
910 goto again;
911 }
912 }
913
914 if (ret >= 0)
915 ret += read;
916
917 return ret;
918 }
919
920 /*
921 * Take cap references to avoid releasing caps to MDS mid-write.
922 *
923 * If we are synchronous, and write with an old snap context, the OSD
924 * may return EOLDSNAPC. In that case, retry the write.. _after_
925 * dropping our cap refs and allowing the pending snap to logically
926 * complete _before_ this write occurs.
927 *
928 * If we are near ENOSPC, write synchronously.
929 */
930 static ssize_t ceph_write_iter(struct kiocb *iocb, struct iov_iter *from)
931 {
932 struct file *file = iocb->ki_filp;
933 struct ceph_file_info *fi = file->private_data;
934 struct inode *inode = file_inode(file);
935 struct ceph_inode_info *ci = ceph_inode(inode);
936 struct ceph_osd_client *osdc =
937 &ceph_sb_to_client(inode->i_sb)->client->osdc;
938 ssize_t count = iov_iter_count(from), written = 0;
939 int err, want, got;
940 loff_t pos = iocb->ki_pos;
941
942 if (ceph_snap(inode) != CEPH_NOSNAP)
943 return -EROFS;
944
945 mutex_lock(&inode->i_mutex);
946
947 /* We can write back this queue in page reclaim */
948 current->backing_dev_info = file->f_mapping->backing_dev_info;
949
950 err = generic_write_checks(file, &pos, &count, S_ISBLK(inode->i_mode));
951 if (err)
952 goto out;
953
954 if (count == 0)
955 goto out;
956 iov_iter_truncate(from, count);
957
958 err = file_remove_suid(file);
959 if (err)
960 goto out;
961
962 err = file_update_time(file);
963 if (err)
964 goto out;
965
966 if (ci->i_inline_version != CEPH_INLINE_NONE) {
967 err = ceph_uninline_data(file, NULL);
968 if (err < 0)
969 goto out;
970 }
971
972 retry_snap:
973 if (ceph_osdmap_flag(osdc->osdmap, CEPH_OSDMAP_FULL)) {
974 err = -ENOSPC;
975 goto out;
976 }
977
978 dout("aio_write %p %llx.%llx %llu~%zd getting caps. i_size %llu\n",
979 inode, ceph_vinop(inode), pos, count, inode->i_size);
980 if (fi->fmode & CEPH_FILE_MODE_LAZY)
981 want = CEPH_CAP_FILE_BUFFER | CEPH_CAP_FILE_LAZYIO;
982 else
983 want = CEPH_CAP_FILE_BUFFER;
984 got = 0;
985 err = ceph_get_caps(ci, CEPH_CAP_FILE_WR, want, pos + count,
986 &got, NULL);
987 if (err < 0)
988 goto out;
989
990 dout("aio_write %p %llx.%llx %llu~%zd got cap refs on %s\n",
991 inode, ceph_vinop(inode), pos, count, ceph_cap_string(got));
992
993 if ((got & (CEPH_CAP_FILE_BUFFER|CEPH_CAP_FILE_LAZYIO)) == 0 ||
994 (file->f_flags & O_DIRECT) || (fi->flags & CEPH_F_SYNC)) {
995 struct iov_iter data;
996 mutex_unlock(&inode->i_mutex);
997 /* we might need to revert back to that point */
998 data = *from;
999 if (file->f_flags & O_DIRECT)
1000 written = ceph_sync_direct_write(iocb, &data, pos);
1001 else
1002 written = ceph_sync_write(iocb, &data, pos);
1003 if (written == -EOLDSNAPC) {
1004 dout("aio_write %p %llx.%llx %llu~%u"
1005 "got EOLDSNAPC, retrying\n",
1006 inode, ceph_vinop(inode),
1007 pos, (unsigned)count);
1008 mutex_lock(&inode->i_mutex);
1009 goto retry_snap;
1010 }
1011 if (written > 0)
1012 iov_iter_advance(from, written);
1013 } else {
1014 loff_t old_size = inode->i_size;
1015 /*
1016 * No need to acquire the i_truncate_mutex. Because
1017 * the MDS revokes Fwb caps before sending truncate
1018 * message to us. We can't get Fwb cap while there
1019 * are pending vmtruncate. So write and vmtruncate
1020 * can not run at the same time
1021 */
1022 written = generic_perform_write(file, from, pos);
1023 if (likely(written >= 0))
1024 iocb->ki_pos = pos + written;
1025 if (inode->i_size > old_size)
1026 ceph_fscache_update_objectsize(inode);
1027 mutex_unlock(&inode->i_mutex);
1028 }
1029
1030 if (written >= 0) {
1031 int dirty;
1032 spin_lock(&ci->i_ceph_lock);
1033 ci->i_inline_version = CEPH_INLINE_NONE;
1034 dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_FILE_WR);
1035 spin_unlock(&ci->i_ceph_lock);
1036 if (dirty)
1037 __mark_inode_dirty(inode, dirty);
1038 }
1039
1040 dout("aio_write %p %llx.%llx %llu~%u dropping cap refs on %s\n",
1041 inode, ceph_vinop(inode), pos, (unsigned)count,
1042 ceph_cap_string(got));
1043 ceph_put_cap_refs(ci, got);
1044
1045 if (written >= 0 &&
1046 ((file->f_flags & O_SYNC) || IS_SYNC(file->f_mapping->host) ||
1047 ceph_osdmap_flag(osdc->osdmap, CEPH_OSDMAP_NEARFULL))) {
1048 err = vfs_fsync_range(file, pos, pos + written - 1, 1);
1049 if (err < 0)
1050 written = err;
1051 }
1052
1053 goto out_unlocked;
1054
1055 out:
1056 mutex_unlock(&inode->i_mutex);
1057 out_unlocked:
1058 current->backing_dev_info = NULL;
1059 return written ? written : err;
1060 }
1061
1062 /*
1063 * llseek. be sure to verify file size on SEEK_END.
1064 */
1065 static loff_t ceph_llseek(struct file *file, loff_t offset, int whence)
1066 {
1067 struct inode *inode = file->f_mapping->host;
1068 int ret;
1069
1070 mutex_lock(&inode->i_mutex);
1071
1072 if (whence == SEEK_END || whence == SEEK_DATA || whence == SEEK_HOLE) {
1073 ret = ceph_do_getattr(inode, CEPH_STAT_CAP_SIZE, false);
1074 if (ret < 0) {
1075 offset = ret;
1076 goto out;
1077 }
1078 }
1079
1080 switch (whence) {
1081 case SEEK_END:
1082 offset += inode->i_size;
1083 break;
1084 case SEEK_CUR:
1085 /*
1086 * Here we special-case the lseek(fd, 0, SEEK_CUR)
1087 * position-querying operation. Avoid rewriting the "same"
1088 * f_pos value back to the file because a concurrent read(),
1089 * write() or lseek() might have altered it
1090 */
1091 if (offset == 0) {
1092 offset = file->f_pos;
1093 goto out;
1094 }
1095 offset += file->f_pos;
1096 break;
1097 case SEEK_DATA:
1098 if (offset >= inode->i_size) {
1099 ret = -ENXIO;
1100 goto out;
1101 }
1102 break;
1103 case SEEK_HOLE:
1104 if (offset >= inode->i_size) {
1105 ret = -ENXIO;
1106 goto out;
1107 }
1108 offset = inode->i_size;
1109 break;
1110 }
1111
1112 offset = vfs_setpos(file, offset, inode->i_sb->s_maxbytes);
1113
1114 out:
1115 mutex_unlock(&inode->i_mutex);
1116 return offset;
1117 }
1118
1119 static inline void ceph_zero_partial_page(
1120 struct inode *inode, loff_t offset, unsigned size)
1121 {
1122 struct page *page;
1123 pgoff_t index = offset >> PAGE_CACHE_SHIFT;
1124
1125 page = find_lock_page(inode->i_mapping, index);
1126 if (page) {
1127 wait_on_page_writeback(page);
1128 zero_user(page, offset & (PAGE_CACHE_SIZE - 1), size);
1129 unlock_page(page);
1130 page_cache_release(page);
1131 }
1132 }
1133
1134 static void ceph_zero_pagecache_range(struct inode *inode, loff_t offset,
1135 loff_t length)
1136 {
1137 loff_t nearly = round_up(offset, PAGE_CACHE_SIZE);
1138 if (offset < nearly) {
1139 loff_t size = nearly - offset;
1140 if (length < size)
1141 size = length;
1142 ceph_zero_partial_page(inode, offset, size);
1143 offset += size;
1144 length -= size;
1145 }
1146 if (length >= PAGE_CACHE_SIZE) {
1147 loff_t size = round_down(length, PAGE_CACHE_SIZE);
1148 truncate_pagecache_range(inode, offset, offset + size - 1);
1149 offset += size;
1150 length -= size;
1151 }
1152 if (length)
1153 ceph_zero_partial_page(inode, offset, length);
1154 }
1155
1156 static int ceph_zero_partial_object(struct inode *inode,
1157 loff_t offset, loff_t *length)
1158 {
1159 struct ceph_inode_info *ci = ceph_inode(inode);
1160 struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
1161 struct ceph_osd_request *req;
1162 int ret = 0;
1163 loff_t zero = 0;
1164 int op;
1165
1166 if (!length) {
1167 op = offset ? CEPH_OSD_OP_DELETE : CEPH_OSD_OP_TRUNCATE;
1168 length = &zero;
1169 } else {
1170 op = CEPH_OSD_OP_ZERO;
1171 }
1172
1173 req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout,
1174 ceph_vino(inode),
1175 offset, length,
1176 0, 1, op,
1177 CEPH_OSD_FLAG_WRITE |
1178 CEPH_OSD_FLAG_ONDISK,
1179 NULL, 0, 0, false);
1180 if (IS_ERR(req)) {
1181 ret = PTR_ERR(req);
1182 goto out;
1183 }
1184
1185 ceph_osdc_build_request(req, offset, NULL, ceph_vino(inode).snap,
1186 &inode->i_mtime);
1187
1188 ret = ceph_osdc_start_request(&fsc->client->osdc, req, false);
1189 if (!ret) {
1190 ret = ceph_osdc_wait_request(&fsc->client->osdc, req);
1191 if (ret == -ENOENT)
1192 ret = 0;
1193 }
1194 ceph_osdc_put_request(req);
1195
1196 out:
1197 return ret;
1198 }
1199
1200 static int ceph_zero_objects(struct inode *inode, loff_t offset, loff_t length)
1201 {
1202 int ret = 0;
1203 struct ceph_inode_info *ci = ceph_inode(inode);
1204 s32 stripe_unit = ceph_file_layout_su(ci->i_layout);
1205 s32 stripe_count = ceph_file_layout_stripe_count(ci->i_layout);
1206 s32 object_size = ceph_file_layout_object_size(ci->i_layout);
1207 u64 object_set_size = object_size * stripe_count;
1208 u64 nearly, t;
1209
1210 /* round offset up to next period boundary */
1211 nearly = offset + object_set_size - 1;
1212 t = nearly;
1213 nearly -= do_div(t, object_set_size);
1214
1215 while (length && offset < nearly) {
1216 loff_t size = length;
1217 ret = ceph_zero_partial_object(inode, offset, &size);
1218 if (ret < 0)
1219 return ret;
1220 offset += size;
1221 length -= size;
1222 }
1223 while (length >= object_set_size) {
1224 int i;
1225 loff_t pos = offset;
1226 for (i = 0; i < stripe_count; ++i) {
1227 ret = ceph_zero_partial_object(inode, pos, NULL);
1228 if (ret < 0)
1229 return ret;
1230 pos += stripe_unit;
1231 }
1232 offset += object_set_size;
1233 length -= object_set_size;
1234 }
1235 while (length) {
1236 loff_t size = length;
1237 ret = ceph_zero_partial_object(inode, offset, &size);
1238 if (ret < 0)
1239 return ret;
1240 offset += size;
1241 length -= size;
1242 }
1243 return ret;
1244 }
1245
1246 static long ceph_fallocate(struct file *file, int mode,
1247 loff_t offset, loff_t length)
1248 {
1249 struct ceph_file_info *fi = file->private_data;
1250 struct inode *inode = file_inode(file);
1251 struct ceph_inode_info *ci = ceph_inode(inode);
1252 struct ceph_osd_client *osdc =
1253 &ceph_inode_to_client(inode)->client->osdc;
1254 int want, got = 0;
1255 int dirty;
1256 int ret = 0;
1257 loff_t endoff = 0;
1258 loff_t size;
1259
1260 if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE))
1261 return -EOPNOTSUPP;
1262
1263 if (!S_ISREG(inode->i_mode))
1264 return -EOPNOTSUPP;
1265
1266 mutex_lock(&inode->i_mutex);
1267
1268 if (ceph_snap(inode) != CEPH_NOSNAP) {
1269 ret = -EROFS;
1270 goto unlock;
1271 }
1272
1273 if (ceph_osdmap_flag(osdc->osdmap, CEPH_OSDMAP_FULL) &&
1274 !(mode & FALLOC_FL_PUNCH_HOLE)) {
1275 ret = -ENOSPC;
1276 goto unlock;
1277 }
1278
1279 if (ci->i_inline_version != CEPH_INLINE_NONE) {
1280 ret = ceph_uninline_data(file, NULL);
1281 if (ret < 0)
1282 goto unlock;
1283 }
1284
1285 size = i_size_read(inode);
1286 if (!(mode & FALLOC_FL_KEEP_SIZE))
1287 endoff = offset + length;
1288
1289 if (fi->fmode & CEPH_FILE_MODE_LAZY)
1290 want = CEPH_CAP_FILE_BUFFER | CEPH_CAP_FILE_LAZYIO;
1291 else
1292 want = CEPH_CAP_FILE_BUFFER;
1293
1294 ret = ceph_get_caps(ci, CEPH_CAP_FILE_WR, want, endoff, &got, NULL);
1295 if (ret < 0)
1296 goto unlock;
1297
1298 if (mode & FALLOC_FL_PUNCH_HOLE) {
1299 if (offset < size)
1300 ceph_zero_pagecache_range(inode, offset, length);
1301 ret = ceph_zero_objects(inode, offset, length);
1302 } else if (endoff > size) {
1303 truncate_pagecache_range(inode, size, -1);
1304 if (ceph_inode_set_size(inode, endoff))
1305 ceph_check_caps(ceph_inode(inode),
1306 CHECK_CAPS_AUTHONLY, NULL);
1307 }
1308
1309 if (!ret) {
1310 spin_lock(&ci->i_ceph_lock);
1311 ci->i_inline_version = CEPH_INLINE_NONE;
1312 dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_FILE_WR);
1313 spin_unlock(&ci->i_ceph_lock);
1314 if (dirty)
1315 __mark_inode_dirty(inode, dirty);
1316 }
1317
1318 ceph_put_cap_refs(ci, got);
1319 unlock:
1320 mutex_unlock(&inode->i_mutex);
1321 return ret;
1322 }
1323
1324 const struct file_operations ceph_file_fops = {
1325 .open = ceph_open,
1326 .release = ceph_release,
1327 .llseek = ceph_llseek,
1328 .read = new_sync_read,
1329 .write = new_sync_write,
1330 .read_iter = ceph_read_iter,
1331 .write_iter = ceph_write_iter,
1332 .mmap = ceph_mmap,
1333 .fsync = ceph_fsync,
1334 .lock = ceph_lock,
1335 .flock = ceph_flock,
1336 .splice_read = generic_file_splice_read,
1337 .splice_write = iter_file_splice_write,
1338 .unlocked_ioctl = ceph_ioctl,
1339 .compat_ioctl = ceph_ioctl,
1340 .fallocate = ceph_fallocate,
1341 };
1342
Linux kernel - Deliverables
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