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[GitHub/exynos8895/android_kernel_samsung_universal8895.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/falloc.h>
11
12 #include "super.h"
13 #include "mds_client.h"
14 #include "cache.h"
15
16 /*
17 * Ceph file operations
18 *
19 * Implement basic open/close functionality, and implement
20 * read/write.
21 *
22 * We implement three modes of file I/O:
23 * - buffered uses the generic_file_aio_{read,write} helpers
24 *
25 * - synchronous is used when there is multi-client read/write
26 * sharing, avoids the page cache, and synchronously waits for an
27 * ack from the OSD.
28 *
29 * - direct io takes the variant of the sync path that references
30 * user pages directly.
31 *
32 * fsync() flushes and waits on dirty pages, but just queues metadata
33 * for writeback: since the MDS can recover size and mtime there is no
34 * need to wait for MDS acknowledgement.
35 */
36
37
38 /*
39 * Prepare an open request. Preallocate ceph_cap to avoid an
40 * inopportune ENOMEM later.
41 */
42 static struct ceph_mds_request *
43 prepare_open_request(struct super_block *sb, int flags, int create_mode)
44 {
45 struct ceph_fs_client *fsc = ceph_sb_to_client(sb);
46 struct ceph_mds_client *mdsc = fsc->mdsc;
47 struct ceph_mds_request *req;
48 int want_auth = USE_ANY_MDS;
49 int op = (flags & O_CREAT) ? CEPH_MDS_OP_CREATE : CEPH_MDS_OP_OPEN;
50
51 if (flags & (O_WRONLY|O_RDWR|O_CREAT|O_TRUNC))
52 want_auth = USE_AUTH_MDS;
53
54 req = ceph_mdsc_create_request(mdsc, op, want_auth);
55 if (IS_ERR(req))
56 goto out;
57 req->r_fmode = ceph_flags_to_mode(flags);
58 req->r_args.open.flags = cpu_to_le32(flags);
59 req->r_args.open.mode = cpu_to_le32(create_mode);
60 out:
61 return req;
62 }
63
64 /*
65 * initialize private struct file data.
66 * if we fail, clean up by dropping fmode reference on the ceph_inode
67 */
68 static int ceph_init_file(struct inode *inode, struct file *file, int fmode)
69 {
70 struct ceph_file_info *cf;
71 int ret = 0;
72 struct ceph_inode_info *ci = ceph_inode(inode);
73 struct ceph_fs_client *fsc = ceph_sb_to_client(inode->i_sb);
74 struct ceph_mds_client *mdsc = fsc->mdsc;
75
76 switch (inode->i_mode & S_IFMT) {
77 case S_IFREG:
78 /* First file open request creates the cookie, we want to keep
79 * this cookie around for the filetime of the inode as not to
80 * have to worry about fscache register / revoke / operation
81 * races.
82 *
83 * Also, if we know the operation is going to invalidate data
84 * (non readonly) just nuke the cache right away.
85 */
86 ceph_fscache_register_inode_cookie(mdsc->fsc, ci);
87 if ((fmode & CEPH_FILE_MODE_WR))
88 ceph_fscache_invalidate(inode);
89 case S_IFDIR:
90 dout("init_file %p %p 0%o (regular)\n", inode, file,
91 inode->i_mode);
92 cf = kmem_cache_alloc(ceph_file_cachep, GFP_NOFS | __GFP_ZERO);
93 if (cf == NULL) {
94 ceph_put_fmode(ceph_inode(inode), fmode); /* clean up */
95 return -ENOMEM;
96 }
97 cf->fmode = fmode;
98 cf->next_offset = 2;
99 file->private_data = cf;
100 BUG_ON(inode->i_fop->release != ceph_release);
101 break;
102
103 case S_IFLNK:
104 dout("init_file %p %p 0%o (symlink)\n", inode, file,
105 inode->i_mode);
106 ceph_put_fmode(ceph_inode(inode), fmode); /* clean up */
107 break;
108
109 default:
110 dout("init_file %p %p 0%o (special)\n", inode, file,
111 inode->i_mode);
112 /*
113 * we need to drop the open ref now, since we don't
114 * have .release set to ceph_release.
115 */
116 ceph_put_fmode(ceph_inode(inode), fmode); /* clean up */
117 BUG_ON(inode->i_fop->release == ceph_release);
118
119 /* call the proper open fop */
120 ret = inode->i_fop->open(inode, file);
121 }
122 return ret;
123 }
124
125 /*
126 * If we already have the requisite capabilities, we can satisfy
127 * the open request locally (no need to request new caps from the
128 * MDS). We do, however, need to inform the MDS (asynchronously)
129 * if our wanted caps set expands.
130 */
131 int ceph_open(struct inode *inode, struct file *file)
132 {
133 struct ceph_inode_info *ci = ceph_inode(inode);
134 struct ceph_fs_client *fsc = ceph_sb_to_client(inode->i_sb);
135 struct ceph_mds_client *mdsc = fsc->mdsc;
136 struct ceph_mds_request *req;
137 struct ceph_file_info *cf = file->private_data;
138 struct inode *parent_inode = NULL;
139 int err;
140 int flags, fmode, wanted;
141
142 if (cf) {
143 dout("open file %p is already opened\n", file);
144 return 0;
145 }
146
147 /* filter out O_CREAT|O_EXCL; vfs did that already. yuck. */
148 flags = file->f_flags & ~(O_CREAT|O_EXCL);
149 if (S_ISDIR(inode->i_mode))
150 flags = O_DIRECTORY; /* mds likes to know */
151
152 dout("open inode %p ino %llx.%llx file %p flags %d (%d)\n", inode,
153 ceph_vinop(inode), file, flags, file->f_flags);
154 fmode = ceph_flags_to_mode(flags);
155 wanted = ceph_caps_for_mode(fmode);
156
157 /* snapped files are read-only */
158 if (ceph_snap(inode) != CEPH_NOSNAP && (file->f_mode & FMODE_WRITE))
159 return -EROFS;
160
161 /* trivially open snapdir */
162 if (ceph_snap(inode) == CEPH_SNAPDIR) {
163 spin_lock(&ci->i_ceph_lock);
164 __ceph_get_fmode(ci, fmode);
165 spin_unlock(&ci->i_ceph_lock);
166 return ceph_init_file(inode, file, fmode);
167 }
168
169 /*
170 * No need to block if we have caps on the auth MDS (for
171 * write) or any MDS (for read). Update wanted set
172 * asynchronously.
173 */
174 spin_lock(&ci->i_ceph_lock);
175 if (__ceph_is_any_real_caps(ci) &&
176 (((fmode & CEPH_FILE_MODE_WR) == 0) || ci->i_auth_cap)) {
177 int mds_wanted = __ceph_caps_mds_wanted(ci);
178 int issued = __ceph_caps_issued(ci, NULL);
179
180 dout("open %p fmode %d want %s issued %s using existing\n",
181 inode, fmode, ceph_cap_string(wanted),
182 ceph_cap_string(issued));
183 __ceph_get_fmode(ci, fmode);
184 spin_unlock(&ci->i_ceph_lock);
185
186 /* adjust wanted? */
187 if ((issued & wanted) != wanted &&
188 (mds_wanted & wanted) != wanted &&
189 ceph_snap(inode) != CEPH_SNAPDIR)
190 ceph_check_caps(ci, 0, NULL);
191
192 return ceph_init_file(inode, file, fmode);
193 } else if (ceph_snap(inode) != CEPH_NOSNAP &&
194 (ci->i_snap_caps & wanted) == wanted) {
195 __ceph_get_fmode(ci, fmode);
196 spin_unlock(&ci->i_ceph_lock);
197 return ceph_init_file(inode, file, fmode);
198 }
199
200 spin_unlock(&ci->i_ceph_lock);
201
202 dout("open fmode %d wants %s\n", fmode, ceph_cap_string(wanted));
203 req = prepare_open_request(inode->i_sb, flags, 0);
204 if (IS_ERR(req)) {
205 err = PTR_ERR(req);
206 goto out;
207 }
208 req->r_inode = inode;
209 ihold(inode);
210
211 req->r_num_caps = 1;
212 if (flags & O_CREAT)
213 parent_inode = ceph_get_dentry_parent_inode(file->f_path.dentry);
214 err = ceph_mdsc_do_request(mdsc, parent_inode, req);
215 iput(parent_inode);
216 if (!err)
217 err = ceph_init_file(inode, file, req->r_fmode);
218 ceph_mdsc_put_request(req);
219 dout("open result=%d on %llx.%llx\n", err, ceph_vinop(inode));
220 out:
221 return err;
222 }
223
224
225 /*
226 * Do a lookup + open with a single request. If we get a non-existent
227 * file or symlink, return 1 so the VFS can retry.
228 */
229 int ceph_atomic_open(struct inode *dir, struct dentry *dentry,
230 struct file *file, unsigned flags, umode_t mode,
231 int *opened)
232 {
233 struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
234 struct ceph_mds_client *mdsc = fsc->mdsc;
235 struct ceph_mds_request *req;
236 struct dentry *dn;
237 struct ceph_acls_info acls = {};
238 int err;
239
240 dout("atomic_open %p dentry %p '%pd' %s flags %d mode 0%o\n",
241 dir, dentry, dentry,
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 if (flags & O_CREAT) {
252 err = ceph_pre_init_acls(dir, &mode, &acls);
253 if (err < 0)
254 return err;
255 }
256
257 /* do the open */
258 req = prepare_open_request(dir->i_sb, flags, mode);
259 if (IS_ERR(req)) {
260 err = PTR_ERR(req);
261 goto out_acl;
262 }
263 req->r_dentry = dget(dentry);
264 req->r_num_caps = 2;
265 if (flags & O_CREAT) {
266 req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
267 req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
268 if (acls.pagelist) {
269 req->r_pagelist = acls.pagelist;
270 acls.pagelist = NULL;
271 }
272 }
273 req->r_locked_dir = dir; /* caller holds dir->i_mutex */
274 err = ceph_mdsc_do_request(mdsc,
275 (flags & (O_CREAT|O_TRUNC)) ? dir : NULL,
276 req);
277 if (err)
278 goto out_req;
279
280 err = ceph_handle_snapdir(req, dentry, err);
281 if (err == 0 && (flags & O_CREAT) && !req->r_reply_info.head->is_dentry)
282 err = ceph_handle_notrace_create(dir, dentry);
283
284 if (d_unhashed(dentry)) {
285 dn = ceph_finish_lookup(req, dentry, err);
286 if (IS_ERR(dn))
287 err = PTR_ERR(dn);
288 } else {
289 /* we were given a hashed negative dentry */
290 dn = NULL;
291 }
292 if (err)
293 goto out_req;
294 if (dn || dentry->d_inode == NULL || S_ISLNK(dentry->d_inode->i_mode)) {
295 /* make vfs retry on splice, ENOENT, or symlink */
296 dout("atomic_open finish_no_open on dn %p\n", dn);
297 err = finish_no_open(file, dn);
298 } else {
299 dout("atomic_open finish_open on dn %p\n", dn);
300 if (req->r_op == CEPH_MDS_OP_CREATE && req->r_reply_info.has_create_ino) {
301 ceph_init_inode_acls(dentry->d_inode, &acls);
302 *opened |= FILE_CREATED;
303 }
304 err = finish_open(file, dentry, ceph_open, opened);
305 }
306 out_req:
307 if (!req->r_err && req->r_target_inode)
308 ceph_put_fmode(ceph_inode(req->r_target_inode), req->r_fmode);
309 ceph_mdsc_put_request(req);
310 out_acl:
311 ceph_release_acls_info(&acls);
312 dout("atomic_open result=%d\n", err);
313 return err;
314 }
315
316 int ceph_release(struct inode *inode, struct file *file)
317 {
318 struct ceph_inode_info *ci = ceph_inode(inode);
319 struct ceph_file_info *cf = file->private_data;
320
321 dout("release inode %p file %p\n", inode, file);
322 ceph_put_fmode(ci, cf->fmode);
323 if (cf->last_readdir)
324 ceph_mdsc_put_request(cf->last_readdir);
325 kfree(cf->last_name);
326 kfree(cf->dir_info);
327 dput(cf->dentry);
328 kmem_cache_free(ceph_file_cachep, cf);
329
330 /* wake up anyone waiting for caps on this inode */
331 wake_up_all(&ci->i_cap_wq);
332 return 0;
333 }
334
335 enum {
336 CHECK_EOF = 1,
337 READ_INLINE = 2,
338 };
339
340 /*
341 * Read a range of bytes striped over one or more objects. Iterate over
342 * objects we stripe over. (That's not atomic, but good enough for now.)
343 *
344 * If we get a short result from the OSD, check against i_size; we need to
345 * only return a short read to the caller if we hit EOF.
346 */
347 static int striped_read(struct inode *inode,
348 u64 off, u64 len,
349 struct page **pages, int num_pages,
350 int *checkeof, bool o_direct,
351 unsigned long buf_align)
352 {
353 struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
354 struct ceph_inode_info *ci = ceph_inode(inode);
355 u64 pos, this_len, left;
356 int io_align, page_align;
357 int pages_left;
358 int read;
359 struct page **page_pos;
360 int ret;
361 bool hit_stripe, was_short;
362
363 /*
364 * we may need to do multiple reads. not atomic, unfortunately.
365 */
366 pos = off;
367 left = len;
368 page_pos = pages;
369 pages_left = num_pages;
370 read = 0;
371 io_align = off & ~PAGE_MASK;
372
373 more:
374 if (o_direct)
375 page_align = (pos - io_align + buf_align) & ~PAGE_MASK;
376 else
377 page_align = pos & ~PAGE_MASK;
378 this_len = left;
379 ret = ceph_osdc_readpages(&fsc->client->osdc, ceph_vino(inode),
380 &ci->i_layout, pos, &this_len,
381 ci->i_truncate_seq,
382 ci->i_truncate_size,
383 page_pos, pages_left, page_align);
384 if (ret == -ENOENT)
385 ret = 0;
386 hit_stripe = this_len < left;
387 was_short = ret >= 0 && ret < this_len;
388 dout("striped_read %llu~%llu (read %u) got %d%s%s\n", pos, left, read,
389 ret, hit_stripe ? " HITSTRIPE" : "", was_short ? " SHORT" : "");
390
391 if (ret >= 0) {
392 int didpages;
393 if (was_short && (pos + ret < inode->i_size)) {
394 u64 tmp = min(this_len - ret,
395 inode->i_size - pos - ret);
396 dout(" zero gap %llu to %llu\n",
397 pos + ret, pos + ret + tmp);
398 ceph_zero_page_vector_range(page_align + read + ret,
399 tmp, pages);
400 ret += tmp;
401 }
402
403 didpages = (page_align + ret) >> PAGE_CACHE_SHIFT;
404 pos += ret;
405 read = pos - off;
406 left -= ret;
407 page_pos += didpages;
408 pages_left -= didpages;
409
410 /* hit stripe and need continue*/
411 if (left && hit_stripe && pos < inode->i_size)
412 goto more;
413 }
414
415 if (read > 0) {
416 ret = read;
417 /* did we bounce off eof? */
418 if (pos + left > inode->i_size)
419 *checkeof = CHECK_EOF;
420 }
421
422 dout("striped_read returns %d\n", ret);
423 return ret;
424 }
425
426 /*
427 * Completely synchronous read and write methods. Direct from __user
428 * buffer to osd, or directly to user pages (if O_DIRECT).
429 *
430 * If the read spans object boundary, just do multiple reads.
431 */
432 static ssize_t ceph_sync_read(struct kiocb *iocb, struct iov_iter *i,
433 int *checkeof)
434 {
435 struct file *file = iocb->ki_filp;
436 struct inode *inode = file_inode(file);
437 struct page **pages;
438 u64 off = iocb->ki_pos;
439 int num_pages, ret;
440 size_t len = iov_iter_count(i);
441
442 dout("sync_read on file %p %llu~%u %s\n", file, off,
443 (unsigned)len,
444 (file->f_flags & O_DIRECT) ? "O_DIRECT" : "");
445
446 if (!len)
447 return 0;
448 /*
449 * flush any page cache pages in this range. this
450 * will make concurrent normal and sync io slow,
451 * but it will at least behave sensibly when they are
452 * in sequence.
453 */
454 ret = filemap_write_and_wait_range(inode->i_mapping, off,
455 off + len);
456 if (ret < 0)
457 return ret;
458
459 if (file->f_flags & O_DIRECT) {
460 while (iov_iter_count(i)) {
461 size_t start;
462 ssize_t n;
463
464 n = iov_iter_get_pages_alloc(i, &pages, INT_MAX, &start);
465 if (n < 0)
466 return n;
467
468 num_pages = (n + start + PAGE_SIZE - 1) / PAGE_SIZE;
469
470 ret = striped_read(inode, off, n,
471 pages, num_pages, checkeof,
472 1, start);
473
474 ceph_put_page_vector(pages, num_pages, true);
475
476 if (ret <= 0)
477 break;
478 off += ret;
479 iov_iter_advance(i, ret);
480 if (ret < n)
481 break;
482 }
483 } else {
484 num_pages = calc_pages_for(off, len);
485 pages = ceph_alloc_page_vector(num_pages, GFP_NOFS);
486 if (IS_ERR(pages))
487 return PTR_ERR(pages);
488 ret = striped_read(inode, off, len, pages,
489 num_pages, checkeof, 0, 0);
490 if (ret > 0) {
491 int l, k = 0;
492 size_t left = ret;
493
494 while (left) {
495 size_t page_off = off & ~PAGE_MASK;
496 size_t copy = min_t(size_t,
497 PAGE_SIZE - page_off, left);
498 l = copy_page_to_iter(pages[k++], page_off,
499 copy, i);
500 off += l;
501 left -= l;
502 if (l < copy)
503 break;
504 }
505 }
506 ceph_release_page_vector(pages, num_pages);
507 }
508
509 if (off > iocb->ki_pos) {
510 ret = off - iocb->ki_pos;
511 iocb->ki_pos = off;
512 }
513
514 dout("sync_read result %d\n", ret);
515 return ret;
516 }
517
518 /*
519 * Write commit request unsafe callback, called to tell us when a
520 * request is unsafe (that is, in flight--has been handed to the
521 * messenger to send to its target osd). It is called again when
522 * we've received a response message indicating the request is
523 * "safe" (its CEPH_OSD_FLAG_ONDISK flag is set), or when a request
524 * is completed early (and unsuccessfully) due to a timeout or
525 * interrupt.
526 *
527 * This is used if we requested both an ACK and ONDISK commit reply
528 * from the OSD.
529 */
530 static void ceph_sync_write_unsafe(struct ceph_osd_request *req, bool unsafe)
531 {
532 struct ceph_inode_info *ci = ceph_inode(req->r_inode);
533
534 dout("%s %p tid %llu %ssafe\n", __func__, req, req->r_tid,
535 unsafe ? "un" : "");
536 if (unsafe) {
537 ceph_get_cap_refs(ci, CEPH_CAP_FILE_WR);
538 spin_lock(&ci->i_unsafe_lock);
539 list_add_tail(&req->r_unsafe_item,
540 &ci->i_unsafe_writes);
541 spin_unlock(&ci->i_unsafe_lock);
542 } else {
543 spin_lock(&ci->i_unsafe_lock);
544 list_del_init(&req->r_unsafe_item);
545 spin_unlock(&ci->i_unsafe_lock);
546 ceph_put_cap_refs(ci, CEPH_CAP_FILE_WR);
547 }
548 }
549
550
551 /*
552 * Synchronous write, straight from __user pointer or user pages.
553 *
554 * If write spans object boundary, just do multiple writes. (For a
555 * correct atomic write, we should e.g. take write locks on all
556 * objects, rollback on failure, etc.)
557 */
558 static ssize_t
559 ceph_sync_direct_write(struct kiocb *iocb, struct iov_iter *from, loff_t pos)
560 {
561 struct file *file = iocb->ki_filp;
562 struct inode *inode = file_inode(file);
563 struct ceph_inode_info *ci = ceph_inode(inode);
564 struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
565 struct ceph_snap_context *snapc;
566 struct ceph_vino vino;
567 struct ceph_osd_request *req;
568 struct page **pages;
569 int num_pages;
570 int written = 0;
571 int flags;
572 int check_caps = 0;
573 int ret;
574 struct timespec mtime = CURRENT_TIME;
575 size_t count = iov_iter_count(from);
576
577 if (ceph_snap(file_inode(file)) != CEPH_NOSNAP)
578 return -EROFS;
579
580 dout("sync_direct_write on file %p %lld~%u\n", file, pos,
581 (unsigned)count);
582
583 ret = filemap_write_and_wait_range(inode->i_mapping, pos, pos + count);
584 if (ret < 0)
585 return ret;
586
587 ret = invalidate_inode_pages2_range(inode->i_mapping,
588 pos >> PAGE_CACHE_SHIFT,
589 (pos + count) >> PAGE_CACHE_SHIFT);
590 if (ret < 0)
591 dout("invalidate_inode_pages2_range returned %d\n", ret);
592
593 flags = CEPH_OSD_FLAG_ORDERSNAP |
594 CEPH_OSD_FLAG_ONDISK |
595 CEPH_OSD_FLAG_WRITE;
596
597 while (iov_iter_count(from) > 0) {
598 u64 len = iov_iter_single_seg_count(from);
599 size_t start;
600 ssize_t n;
601
602 snapc = ci->i_snap_realm->cached_context;
603 vino = ceph_vino(inode);
604 req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout,
605 vino, pos, &len, 0,
606 2,/*include a 'startsync' command*/
607 CEPH_OSD_OP_WRITE, flags, snapc,
608 ci->i_truncate_seq,
609 ci->i_truncate_size,
610 false);
611 if (IS_ERR(req)) {
612 ret = PTR_ERR(req);
613 break;
614 }
615
616 osd_req_op_init(req, 1, CEPH_OSD_OP_STARTSYNC);
617
618 n = iov_iter_get_pages_alloc(from, &pages, len, &start);
619 if (unlikely(n < 0)) {
620 ret = n;
621 ceph_osdc_put_request(req);
622 break;
623 }
624
625 num_pages = (n + start + PAGE_SIZE - 1) / PAGE_SIZE;
626 /*
627 * throw out any page cache pages in this range. this
628 * may block.
629 */
630 truncate_inode_pages_range(inode->i_mapping, pos,
631 (pos+n) | (PAGE_CACHE_SIZE-1));
632 osd_req_op_extent_osd_data_pages(req, 0, pages, n, start,
633 false, false);
634
635 /* BUG_ON(vino.snap != CEPH_NOSNAP); */
636 ceph_osdc_build_request(req, pos, snapc, vino.snap, &mtime);
637
638 ret = ceph_osdc_start_request(&fsc->client->osdc, req, false);
639 if (!ret)
640 ret = ceph_osdc_wait_request(&fsc->client->osdc, req);
641
642 ceph_put_page_vector(pages, num_pages, false);
643
644 ceph_osdc_put_request(req);
645 if (ret)
646 break;
647 pos += n;
648 written += n;
649 iov_iter_advance(from, n);
650
651 if (pos > i_size_read(inode)) {
652 check_caps = ceph_inode_set_size(inode, pos);
653 if (check_caps)
654 ceph_check_caps(ceph_inode(inode),
655 CHECK_CAPS_AUTHONLY,
656 NULL);
657 }
658 }
659
660 if (ret != -EOLDSNAPC && written > 0) {
661 iocb->ki_pos = pos;
662 ret = written;
663 }
664 return ret;
665 }
666
667
668 /*
669 * Synchronous write, straight from __user pointer or user pages.
670 *
671 * If write spans object boundary, just do multiple writes. (For a
672 * correct atomic write, we should e.g. take write locks on all
673 * objects, rollback on failure, etc.)
674 */
675 static ssize_t
676 ceph_sync_write(struct kiocb *iocb, struct iov_iter *from, loff_t pos)
677 {
678 struct file *file = iocb->ki_filp;
679 struct inode *inode = file_inode(file);
680 struct ceph_inode_info *ci = ceph_inode(inode);
681 struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
682 struct ceph_snap_context *snapc;
683 struct ceph_vino vino;
684 struct ceph_osd_request *req;
685 struct page **pages;
686 u64 len;
687 int num_pages;
688 int written = 0;
689 int flags;
690 int check_caps = 0;
691 int ret;
692 struct timespec mtime = CURRENT_TIME;
693 size_t count = iov_iter_count(from);
694
695 if (ceph_snap(file_inode(file)) != CEPH_NOSNAP)
696 return -EROFS;
697
698 dout("sync_write on file %p %lld~%u\n", file, pos, (unsigned)count);
699
700 ret = filemap_write_and_wait_range(inode->i_mapping, pos, pos + count);
701 if (ret < 0)
702 return ret;
703
704 ret = invalidate_inode_pages2_range(inode->i_mapping,
705 pos >> PAGE_CACHE_SHIFT,
706 (pos + count) >> PAGE_CACHE_SHIFT);
707 if (ret < 0)
708 dout("invalidate_inode_pages2_range returned %d\n", ret);
709
710 flags = CEPH_OSD_FLAG_ORDERSNAP |
711 CEPH_OSD_FLAG_ONDISK |
712 CEPH_OSD_FLAG_WRITE |
713 CEPH_OSD_FLAG_ACK;
714
715 while ((len = iov_iter_count(from)) > 0) {
716 size_t left;
717 int n;
718
719 snapc = ci->i_snap_realm->cached_context;
720 vino = ceph_vino(inode);
721 req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout,
722 vino, pos, &len, 0, 1,
723 CEPH_OSD_OP_WRITE, flags, snapc,
724 ci->i_truncate_seq,
725 ci->i_truncate_size,
726 false);
727 if (IS_ERR(req)) {
728 ret = PTR_ERR(req);
729 break;
730 }
731
732 /*
733 * write from beginning of first page,
734 * regardless of io alignment
735 */
736 num_pages = (len + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
737
738 pages = ceph_alloc_page_vector(num_pages, GFP_NOFS);
739 if (IS_ERR(pages)) {
740 ret = PTR_ERR(pages);
741 goto out;
742 }
743
744 left = len;
745 for (n = 0; n < num_pages; n++) {
746 size_t plen = min_t(size_t, left, PAGE_SIZE);
747 ret = copy_page_from_iter(pages[n], 0, plen, from);
748 if (ret != plen) {
749 ret = -EFAULT;
750 break;
751 }
752 left -= ret;
753 }
754
755 if (ret < 0) {
756 ceph_release_page_vector(pages, num_pages);
757 goto out;
758 }
759
760 /* get a second commit callback */
761 req->r_unsafe_callback = ceph_sync_write_unsafe;
762 req->r_inode = inode;
763
764 osd_req_op_extent_osd_data_pages(req, 0, pages, len, 0,
765 false, true);
766
767 /* BUG_ON(vino.snap != CEPH_NOSNAP); */
768 ceph_osdc_build_request(req, pos, snapc, vino.snap, &mtime);
769
770 ret = ceph_osdc_start_request(&fsc->client->osdc, req, false);
771 if (!ret)
772 ret = ceph_osdc_wait_request(&fsc->client->osdc, req);
773
774 out:
775 ceph_osdc_put_request(req);
776 if (ret == 0) {
777 pos += len;
778 written += len;
779
780 if (pos > i_size_read(inode)) {
781 check_caps = ceph_inode_set_size(inode, pos);
782 if (check_caps)
783 ceph_check_caps(ceph_inode(inode),
784 CHECK_CAPS_AUTHONLY,
785 NULL);
786 }
787 } else
788 break;
789 }
790
791 if (ret != -EOLDSNAPC && written > 0) {
792 ret = written;
793 iocb->ki_pos = pos;
794 }
795 return ret;
796 }
797
798 /*
799 * Wrap generic_file_aio_read with checks for cap bits on the inode.
800 * Atomically grab references, so that those bits are not released
801 * back to the MDS mid-read.
802 *
803 * Hmm, the sync read case isn't actually async... should it be?
804 */
805 static ssize_t ceph_read_iter(struct kiocb *iocb, struct iov_iter *to)
806 {
807 struct file *filp = iocb->ki_filp;
808 struct ceph_file_info *fi = filp->private_data;
809 size_t len = iov_iter_count(to);
810 struct inode *inode = file_inode(filp);
811 struct ceph_inode_info *ci = ceph_inode(inode);
812 struct page *pinned_page = NULL;
813 ssize_t ret;
814 int want, got = 0;
815 int retry_op = 0, read = 0;
816
817 again:
818 dout("aio_read %p %llx.%llx %llu~%u trying to get caps on %p\n",
819 inode, ceph_vinop(inode), iocb->ki_pos, (unsigned)len, inode);
820
821 if (fi->fmode & CEPH_FILE_MODE_LAZY)
822 want = CEPH_CAP_FILE_CACHE | CEPH_CAP_FILE_LAZYIO;
823 else
824 want = CEPH_CAP_FILE_CACHE;
825 ret = ceph_get_caps(ci, CEPH_CAP_FILE_RD, want, -1, &got, &pinned_page);
826 if (ret < 0)
827 return ret;
828
829 if ((got & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)) == 0 ||
830 (iocb->ki_filp->f_flags & O_DIRECT) ||
831 (fi->flags & CEPH_F_SYNC)) {
832
833 dout("aio_sync_read %p %llx.%llx %llu~%u got cap refs on %s\n",
834 inode, ceph_vinop(inode), iocb->ki_pos, (unsigned)len,
835 ceph_cap_string(got));
836
837 if (ci->i_inline_version == CEPH_INLINE_NONE) {
838 /* hmm, this isn't really async... */
839 ret = ceph_sync_read(iocb, to, &retry_op);
840 } else {
841 retry_op = READ_INLINE;
842 }
843 } else {
844 dout("aio_read %p %llx.%llx %llu~%u got cap refs on %s\n",
845 inode, ceph_vinop(inode), iocb->ki_pos, (unsigned)len,
846 ceph_cap_string(got));
847
848 ret = generic_file_read_iter(iocb, to);
849 }
850 dout("aio_read %p %llx.%llx dropping cap refs on %s = %d\n",
851 inode, ceph_vinop(inode), ceph_cap_string(got), (int)ret);
852 if (pinned_page) {
853 page_cache_release(pinned_page);
854 pinned_page = NULL;
855 }
856 ceph_put_cap_refs(ci, got);
857 if (retry_op && ret >= 0) {
858 int statret;
859 struct page *page = NULL;
860 loff_t i_size;
861 if (retry_op == READ_INLINE) {
862 page = __page_cache_alloc(GFP_NOFS);
863 if (!page)
864 return -ENOMEM;
865 }
866
867 statret = __ceph_do_getattr(inode, page,
868 CEPH_STAT_CAP_INLINE_DATA, !!page);
869 if (statret < 0) {
870 __free_page(page);
871 if (statret == -ENODATA) {
872 BUG_ON(retry_op != READ_INLINE);
873 goto again;
874 }
875 return statret;
876 }
877
878 i_size = i_size_read(inode);
879 if (retry_op == READ_INLINE) {
880 /* does not support inline data > PAGE_SIZE */
881 if (i_size > PAGE_CACHE_SIZE) {
882 ret = -EIO;
883 } else if (iocb->ki_pos < i_size) {
884 loff_t end = min_t(loff_t, i_size,
885 iocb->ki_pos + len);
886 if (statret < end)
887 zero_user_segment(page, statret, end);
888 ret = copy_page_to_iter(page,
889 iocb->ki_pos & ~PAGE_MASK,
890 end - iocb->ki_pos, to);
891 iocb->ki_pos += ret;
892 } else {
893 ret = 0;
894 }
895 __free_pages(page, 0);
896 return ret;
897 }
898
899 /* hit EOF or hole? */
900 if (retry_op == CHECK_EOF && iocb->ki_pos < i_size &&
901 ret < len) {
902 dout("sync_read hit hole, ppos %lld < size %lld"
903 ", reading more\n", iocb->ki_pos,
904 inode->i_size);
905
906 read += ret;
907 len -= ret;
908 retry_op = 0;
909 goto again;
910 }
911 }
912
913 if (ret >= 0)
914 ret += read;
915
916 return ret;
917 }
918
919 /*
920 * Take cap references to avoid releasing caps to MDS mid-write.
921 *
922 * If we are synchronous, and write with an old snap context, the OSD
923 * may return EOLDSNAPC. In that case, retry the write.. _after_
924 * dropping our cap refs and allowing the pending snap to logically
925 * complete _before_ this write occurs.
926 *
927 * If we are near ENOSPC, write synchronously.
928 */
929 static ssize_t ceph_write_iter(struct kiocb *iocb, struct iov_iter *from)
930 {
931 struct file *file = iocb->ki_filp;
932 struct ceph_file_info *fi = file->private_data;
933 struct inode *inode = file_inode(file);
934 struct ceph_inode_info *ci = ceph_inode(inode);
935 struct ceph_osd_client *osdc =
936 &ceph_sb_to_client(inode->i_sb)->client->osdc;
937 ssize_t count = iov_iter_count(from), written = 0;
938 int err, want, got;
939 loff_t pos = iocb->ki_pos;
940
941 if (ceph_snap(inode) != CEPH_NOSNAP)
942 return -EROFS;
943
944 mutex_lock(&inode->i_mutex);
945
946 /* We can write back this queue in page reclaim */
947 current->backing_dev_info = inode_to_bdi(inode);
948
949 err = generic_write_checks(file, &pos, &count, S_ISBLK(inode->i_mode));
950 if (err)
951 goto out;
952
953 if (count == 0)
954 goto out;
955 iov_iter_truncate(from, count);
956
957 err = file_remove_suid(file);
958 if (err)
959 goto out;
960
961 err = file_update_time(file);
962 if (err)
963 goto out;
964
965 if (ci->i_inline_version != CEPH_INLINE_NONE) {
966 err = ceph_uninline_data(file, NULL);
967 if (err < 0)
968 goto out;
969 }
970
971 retry_snap:
972 if (ceph_osdmap_flag(osdc->osdmap, CEPH_OSDMAP_FULL)) {
973 err = -ENOSPC;
974 goto out;
975 }
976
977 dout("aio_write %p %llx.%llx %llu~%zd getting caps. i_size %llu\n",
978 inode, ceph_vinop(inode), pos, count, inode->i_size);
979 if (fi->fmode & CEPH_FILE_MODE_LAZY)
980 want = CEPH_CAP_FILE_BUFFER | CEPH_CAP_FILE_LAZYIO;
981 else
982 want = CEPH_CAP_FILE_BUFFER;
983 got = 0;
984 err = ceph_get_caps(ci, CEPH_CAP_FILE_WR, want, pos + count,
985 &got, NULL);
986 if (err < 0)
987 goto out;
988
989 dout("aio_write %p %llx.%llx %llu~%zd got cap refs on %s\n",
990 inode, ceph_vinop(inode), pos, count, ceph_cap_string(got));
991
992 if ((got & (CEPH_CAP_FILE_BUFFER|CEPH_CAP_FILE_LAZYIO)) == 0 ||
993 (file->f_flags & O_DIRECT) || (fi->flags & CEPH_F_SYNC)) {
994 struct iov_iter data;
995 mutex_unlock(&inode->i_mutex);
996 /* we might need to revert back to that point */
997 data = *from;
998 if (file->f_flags & O_DIRECT)
999 written = ceph_sync_direct_write(iocb, &data, pos);
1000 else
1001 written = ceph_sync_write(iocb, &data, pos);
1002 if (written == -EOLDSNAPC) {
1003 dout("aio_write %p %llx.%llx %llu~%u"
1004 "got EOLDSNAPC, retrying\n",
1005 inode, ceph_vinop(inode),
1006 pos, (unsigned)count);
1007 mutex_lock(&inode->i_mutex);
1008 goto retry_snap;
1009 }
1010 if (written > 0)
1011 iov_iter_advance(from, written);
1012 } else {
1013 loff_t old_size = inode->i_size;
1014 /*
1015 * No need to acquire the i_truncate_mutex. Because
1016 * the MDS revokes Fwb caps before sending truncate
1017 * message to us. We can't get Fwb cap while there
1018 * are pending vmtruncate. So write and vmtruncate
1019 * can not run at the same time
1020 */
1021 written = generic_perform_write(file, from, pos);
1022 if (likely(written >= 0))
1023 iocb->ki_pos = pos + written;
1024 if (inode->i_size > old_size)
1025 ceph_fscache_update_objectsize(inode);
1026 mutex_unlock(&inode->i_mutex);
1027 }
1028
1029 if (written >= 0) {
1030 int dirty;
1031 spin_lock(&ci->i_ceph_lock);
1032 ci->i_inline_version = CEPH_INLINE_NONE;
1033 dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_FILE_WR);
1034 spin_unlock(&ci->i_ceph_lock);
1035 if (dirty)
1036 __mark_inode_dirty(inode, dirty);
1037 }
1038
1039 dout("aio_write %p %llx.%llx %llu~%u dropping cap refs on %s\n",
1040 inode, ceph_vinop(inode), pos, (unsigned)count,
1041 ceph_cap_string(got));
1042 ceph_put_cap_refs(ci, got);
1043
1044 if (written >= 0 &&
1045 ((file->f_flags & O_SYNC) || IS_SYNC(file->f_mapping->host) ||
1046 ceph_osdmap_flag(osdc->osdmap, CEPH_OSDMAP_NEARFULL))) {
1047 err = vfs_fsync_range(file, pos, pos + written - 1, 1);
1048 if (err < 0)
1049 written = err;
1050 }
1051
1052 goto out_unlocked;
1053
1054 out:
1055 mutex_unlock(&inode->i_mutex);
1056 out_unlocked:
1057 current->backing_dev_info = NULL;
1058 return written ? written : err;
1059 }
1060
1061 /*
1062 * llseek. be sure to verify file size on SEEK_END.
1063 */
1064 static loff_t ceph_llseek(struct file *file, loff_t offset, int whence)
1065 {
1066 struct inode *inode = file->f_mapping->host;
1067 int ret;
1068
1069 mutex_lock(&inode->i_mutex);
1070
1071 if (whence == SEEK_END || whence == SEEK_DATA || whence == SEEK_HOLE) {
1072 ret = ceph_do_getattr(inode, CEPH_STAT_CAP_SIZE, false);
1073 if (ret < 0) {
1074 offset = ret;
1075 goto out;
1076 }
1077 }
1078
1079 switch (whence) {
1080 case SEEK_END:
1081 offset += inode->i_size;
1082 break;
1083 case SEEK_CUR:
1084 /*
1085 * Here we special-case the lseek(fd, 0, SEEK_CUR)
1086 * position-querying operation. Avoid rewriting the "same"
1087 * f_pos value back to the file because a concurrent read(),
1088 * write() or lseek() might have altered it
1089 */
1090 if (offset == 0) {
1091 offset = file->f_pos;
1092 goto out;
1093 }
1094 offset += file->f_pos;
1095 break;
1096 case SEEK_DATA:
1097 if (offset >= inode->i_size) {
1098 ret = -ENXIO;
1099 goto out;
1100 }
1101 break;
1102 case SEEK_HOLE:
1103 if (offset >= inode->i_size) {
1104 ret = -ENXIO;
1105 goto out;
1106 }
1107 offset = inode->i_size;
1108 break;
1109 }
1110
1111 offset = vfs_setpos(file, offset, inode->i_sb->s_maxbytes);
1112
1113 out:
1114 mutex_unlock(&inode->i_mutex);
1115 return offset;
1116 }
1117
1118 static inline void ceph_zero_partial_page(
1119 struct inode *inode, loff_t offset, unsigned size)
1120 {
1121 struct page *page;
1122 pgoff_t index = offset >> PAGE_CACHE_SHIFT;
1123
1124 page = find_lock_page(inode->i_mapping, index);
1125 if (page) {
1126 wait_on_page_writeback(page);
1127 zero_user(page, offset & (PAGE_CACHE_SIZE - 1), size);
1128 unlock_page(page);
1129 page_cache_release(page);
1130 }
1131 }
1132
1133 static void ceph_zero_pagecache_range(struct inode *inode, loff_t offset,
1134 loff_t length)
1135 {
1136 loff_t nearly = round_up(offset, PAGE_CACHE_SIZE);
1137 if (offset < nearly) {
1138 loff_t size = nearly - offset;
1139 if (length < size)
1140 size = length;
1141 ceph_zero_partial_page(inode, offset, size);
1142 offset += size;
1143 length -= size;
1144 }
1145 if (length >= PAGE_CACHE_SIZE) {
1146 loff_t size = round_down(length, PAGE_CACHE_SIZE);
1147 truncate_pagecache_range(inode, offset, offset + size - 1);
1148 offset += size;
1149 length -= size;
1150 }
1151 if (length)
1152 ceph_zero_partial_page(inode, offset, length);
1153 }
1154
1155 static int ceph_zero_partial_object(struct inode *inode,
1156 loff_t offset, loff_t *length)
1157 {
1158 struct ceph_inode_info *ci = ceph_inode(inode);
1159 struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
1160 struct ceph_osd_request *req;
1161 int ret = 0;
1162 loff_t zero = 0;
1163 int op;
1164
1165 if (!length) {
1166 op = offset ? CEPH_OSD_OP_DELETE : CEPH_OSD_OP_TRUNCATE;
1167 length = &zero;
1168 } else {
1169 op = CEPH_OSD_OP_ZERO;
1170 }
1171
1172 req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout,
1173 ceph_vino(inode),
1174 offset, length,
1175 0, 1, op,
1176 CEPH_OSD_FLAG_WRITE |
1177 CEPH_OSD_FLAG_ONDISK,
1178 NULL, 0, 0, false);
1179 if (IS_ERR(req)) {
1180 ret = PTR_ERR(req);
1181 goto out;
1182 }
1183
1184 ceph_osdc_build_request(req, offset, NULL, ceph_vino(inode).snap,
1185 &inode->i_mtime);
1186
1187 ret = ceph_osdc_start_request(&fsc->client->osdc, req, false);
1188 if (!ret) {
1189 ret = ceph_osdc_wait_request(&fsc->client->osdc, req);
1190 if (ret == -ENOENT)
1191 ret = 0;
1192 }
1193 ceph_osdc_put_request(req);
1194
1195 out:
1196 return ret;
1197 }
1198
1199 static int ceph_zero_objects(struct inode *inode, loff_t offset, loff_t length)
1200 {
1201 int ret = 0;
1202 struct ceph_inode_info *ci = ceph_inode(inode);
1203 s32 stripe_unit = ceph_file_layout_su(ci->i_layout);
1204 s32 stripe_count = ceph_file_layout_stripe_count(ci->i_layout);
1205 s32 object_size = ceph_file_layout_object_size(ci->i_layout);
1206 u64 object_set_size = object_size * stripe_count;
1207 u64 nearly, t;
1208
1209 /* round offset up to next period boundary */
1210 nearly = offset + object_set_size - 1;
1211 t = nearly;
1212 nearly -= do_div(t, object_set_size);
1213
1214 while (length && offset < nearly) {
1215 loff_t size = length;
1216 ret = ceph_zero_partial_object(inode, offset, &size);
1217 if (ret < 0)
1218 return ret;
1219 offset += size;
1220 length -= size;
1221 }
1222 while (length >= object_set_size) {
1223 int i;
1224 loff_t pos = offset;
1225 for (i = 0; i < stripe_count; ++i) {
1226 ret = ceph_zero_partial_object(inode, pos, NULL);
1227 if (ret < 0)
1228 return ret;
1229 pos += stripe_unit;
1230 }
1231 offset += object_set_size;
1232 length -= object_set_size;
1233 }
1234 while (length) {
1235 loff_t size = length;
1236 ret = ceph_zero_partial_object(inode, offset, &size);
1237 if (ret < 0)
1238 return ret;
1239 offset += size;
1240 length -= size;
1241 }
1242 return ret;
1243 }
1244
1245 static long ceph_fallocate(struct file *file, int mode,
1246 loff_t offset, loff_t length)
1247 {
1248 struct ceph_file_info *fi = file->private_data;
1249 struct inode *inode = file_inode(file);
1250 struct ceph_inode_info *ci = ceph_inode(inode);
1251 struct ceph_osd_client *osdc =
1252 &ceph_inode_to_client(inode)->client->osdc;
1253 int want, got = 0;
1254 int dirty;
1255 int ret = 0;
1256 loff_t endoff = 0;
1257 loff_t size;
1258
1259 if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE))
1260 return -EOPNOTSUPP;
1261
1262 if (!S_ISREG(inode->i_mode))
1263 return -EOPNOTSUPP;
1264
1265 mutex_lock(&inode->i_mutex);
1266
1267 if (ceph_snap(inode) != CEPH_NOSNAP) {
1268 ret = -EROFS;
1269 goto unlock;
1270 }
1271
1272 if (ceph_osdmap_flag(osdc->osdmap, CEPH_OSDMAP_FULL) &&
1273 !(mode & FALLOC_FL_PUNCH_HOLE)) {
1274 ret = -ENOSPC;
1275 goto unlock;
1276 }
1277
1278 if (ci->i_inline_version != CEPH_INLINE_NONE) {
1279 ret = ceph_uninline_data(file, NULL);
1280 if (ret < 0)
1281 goto unlock;
1282 }
1283
1284 size = i_size_read(inode);
1285 if (!(mode & FALLOC_FL_KEEP_SIZE))
1286 endoff = offset + length;
1287
1288 if (fi->fmode & CEPH_FILE_MODE_LAZY)
1289 want = CEPH_CAP_FILE_BUFFER | CEPH_CAP_FILE_LAZYIO;
1290 else
1291 want = CEPH_CAP_FILE_BUFFER;
1292
1293 ret = ceph_get_caps(ci, CEPH_CAP_FILE_WR, want, endoff, &got, NULL);
1294 if (ret < 0)
1295 goto unlock;
1296
1297 if (mode & FALLOC_FL_PUNCH_HOLE) {
1298 if (offset < size)
1299 ceph_zero_pagecache_range(inode, offset, length);
1300 ret = ceph_zero_objects(inode, offset, length);
1301 } else if (endoff > size) {
1302 truncate_pagecache_range(inode, size, -1);
1303 if (ceph_inode_set_size(inode, endoff))
1304 ceph_check_caps(ceph_inode(inode),
1305 CHECK_CAPS_AUTHONLY, NULL);
1306 }
1307
1308 if (!ret) {
1309 spin_lock(&ci->i_ceph_lock);
1310 ci->i_inline_version = CEPH_INLINE_NONE;
1311 dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_FILE_WR);
1312 spin_unlock(&ci->i_ceph_lock);
1313 if (dirty)
1314 __mark_inode_dirty(inode, dirty);
1315 }
1316
1317 ceph_put_cap_refs(ci, got);
1318 unlock:
1319 mutex_unlock(&inode->i_mutex);
1320 return ret;
1321 }
1322
1323 const struct file_operations ceph_file_fops = {
1324 .open = ceph_open,
1325 .release = ceph_release,
1326 .llseek = ceph_llseek,
1327 .read = new_sync_read,
1328 .write = new_sync_write,
1329 .read_iter = ceph_read_iter,
1330 .write_iter = ceph_write_iter,
1331 .mmap = ceph_mmap,
1332 .fsync = ceph_fsync,
1333 .lock = ceph_lock,
1334 .flock = ceph_flock,
1335 .splice_read = generic_file_splice_read,
1336 .splice_write = iter_file_splice_write,
1337 .unlocked_ioctl = ceph_ioctl,
1338 .compat_ioctl = ceph_ioctl,
1339 .fallocate = ceph_fallocate,
1340 };
1341