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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 * Calculate the length sum of direct io vectors that can
39 * be combined into one page vector.
40 */
41static size_t dio_get_pagev_size(const struct iov_iter *it)
42{
43 const struct iovec *iov = it->iov;
44 const struct iovec *iovend = iov + it->nr_segs;
45 size_t size;
46
47 size = iov->iov_len - it->iov_offset;
48 /*
49 * An iov can be page vectored when both the current tail
50 * and the next base are page aligned.
51 */
52 while (PAGE_ALIGNED((iov->iov_base + iov->iov_len)) &&
53 (++iov < iovend && PAGE_ALIGNED((iov->iov_base)))) {
54 size += iov->iov_len;
55 }
56 dout("dio_get_pagevlen len = %zu\n", size);
57 return size;
58}
59
60/*
61 * Allocate a page vector based on (@it, @nbytes).
62 * The return value is the tuple describing a page vector,
63 * that is (@pages, @page_align, @num_pages).
64 */
65static struct page **
66dio_get_pages_alloc(const struct iov_iter *it, size_t nbytes,
67 size_t *page_align, int *num_pages)
68{
69 struct iov_iter tmp_it = *it;
70 size_t align;
71 struct page **pages;
72 int ret = 0, idx, npages;
73
74 align = (unsigned long)(it->iov->iov_base + it->iov_offset) &
75 (PAGE_SIZE - 1);
76 npages = calc_pages_for(align, nbytes);
77 pages = kmalloc(sizeof(*pages) * npages, GFP_KERNEL);
78 if (!pages) {
79 pages = vmalloc(sizeof(*pages) * npages);
80 if (!pages)
81 return ERR_PTR(-ENOMEM);
82 }
83
84 for (idx = 0; idx < npages; ) {
85 size_t start;
86 ret = iov_iter_get_pages(&tmp_it, pages + idx, nbytes,
87 npages - idx, &start);
88 if (ret < 0)
89 goto fail;
90
91 iov_iter_advance(&tmp_it, ret);
92 nbytes -= ret;
93 idx += (ret + start + PAGE_SIZE - 1) / PAGE_SIZE;
94 }
95
96 BUG_ON(nbytes != 0);
97 *num_pages = npages;
98 *page_align = align;
99 dout("dio_get_pages_alloc: got %d pages align %zu\n", npages, align);
100 return pages;
101fail:
102 ceph_put_page_vector(pages, idx, false);
103 return ERR_PTR(ret);
104}
105
106/*
107 * Prepare an open request. Preallocate ceph_cap to avoid an
108 * inopportune ENOMEM later.
109 */
110static struct ceph_mds_request *
111prepare_open_request(struct super_block *sb, int flags, int create_mode)
112{
113 struct ceph_fs_client *fsc = ceph_sb_to_client(sb);
114 struct ceph_mds_client *mdsc = fsc->mdsc;
115 struct ceph_mds_request *req;
116 int want_auth = USE_ANY_MDS;
117 int op = (flags & O_CREAT) ? CEPH_MDS_OP_CREATE : CEPH_MDS_OP_OPEN;
118
119 if (flags & (O_WRONLY|O_RDWR|O_CREAT|O_TRUNC))
120 want_auth = USE_AUTH_MDS;
121
122 req = ceph_mdsc_create_request(mdsc, op, want_auth);
123 if (IS_ERR(req))
124 goto out;
125 req->r_fmode = ceph_flags_to_mode(flags);
126 req->r_args.open.flags = cpu_to_le32(flags);
127 req->r_args.open.mode = cpu_to_le32(create_mode);
128out:
129 return req;
130}
131
132/*
133 * initialize private struct file data.
134 * if we fail, clean up by dropping fmode reference on the ceph_inode
135 */
136static int ceph_init_file(struct inode *inode, struct file *file, int fmode)
137{
138 struct ceph_file_info *cf;
139 int ret = 0;
140 struct ceph_inode_info *ci = ceph_inode(inode);
141 struct ceph_fs_client *fsc = ceph_sb_to_client(inode->i_sb);
142 struct ceph_mds_client *mdsc = fsc->mdsc;
143
144 switch (inode->i_mode & S_IFMT) {
145 case S_IFREG:
146 /* First file open request creates the cookie, we want to keep
147 * this cookie around for the filetime of the inode as not to
148 * have to worry about fscache register / revoke / operation
149 * races.
150 *
151 * Also, if we know the operation is going to invalidate data
152 * (non readonly) just nuke the cache right away.
153 */
154 ceph_fscache_register_inode_cookie(mdsc->fsc, ci);
155 if ((fmode & CEPH_FILE_MODE_WR))
156 ceph_fscache_invalidate(inode);
157 case S_IFDIR:
158 dout("init_file %p %p 0%o (regular)\n", inode, file,
159 inode->i_mode);
160 cf = kmem_cache_zalloc(ceph_file_cachep, GFP_KERNEL);
161 if (cf == NULL) {
162 ceph_put_fmode(ceph_inode(inode), fmode); /* clean up */
163 return -ENOMEM;
164 }
165 cf->fmode = fmode;
166 cf->next_offset = 2;
167 cf->readdir_cache_idx = -1;
168 file->private_data = cf;
169 BUG_ON(inode->i_fop->release != ceph_release);
170 break;
171
172 case S_IFLNK:
173 dout("init_file %p %p 0%o (symlink)\n", inode, file,
174 inode->i_mode);
175 ceph_put_fmode(ceph_inode(inode), fmode); /* clean up */
176 break;
177
178 default:
179 dout("init_file %p %p 0%o (special)\n", inode, file,
180 inode->i_mode);
181 /*
182 * we need to drop the open ref now, since we don't
183 * have .release set to ceph_release.
184 */
185 ceph_put_fmode(ceph_inode(inode), fmode); /* clean up */
186 BUG_ON(inode->i_fop->release == ceph_release);
187
188 /* call the proper open fop */
189 ret = inode->i_fop->open(inode, file);
190 }
191 return ret;
192}
193
194/*
195 * If we already have the requisite capabilities, we can satisfy
196 * the open request locally (no need to request new caps from the
197 * MDS). We do, however, need to inform the MDS (asynchronously)
198 * if our wanted caps set expands.
199 */
200int ceph_open(struct inode *inode, struct file *file)
201{
202 struct ceph_inode_info *ci = ceph_inode(inode);
203 struct ceph_fs_client *fsc = ceph_sb_to_client(inode->i_sb);
204 struct ceph_mds_client *mdsc = fsc->mdsc;
205 struct ceph_mds_request *req;
206 struct ceph_file_info *cf = file->private_data;
207 int err;
208 int flags, fmode, wanted;
209
210 if (cf) {
211 dout("open file %p is already opened\n", file);
212 return 0;
213 }
214
215 /* filter out O_CREAT|O_EXCL; vfs did that already. yuck. */
216 flags = file->f_flags & ~(O_CREAT|O_EXCL);
217 if (S_ISDIR(inode->i_mode))
218 flags = O_DIRECTORY; /* mds likes to know */
219
220 dout("open inode %p ino %llx.%llx file %p flags %d (%d)\n", inode,
221 ceph_vinop(inode), file, flags, file->f_flags);
222 fmode = ceph_flags_to_mode(flags);
223 wanted = ceph_caps_for_mode(fmode);
224
225 /* snapped files are read-only */
226 if (ceph_snap(inode) != CEPH_NOSNAP && (file->f_mode & FMODE_WRITE))
227 return -EROFS;
228
229 /* trivially open snapdir */
230 if (ceph_snap(inode) == CEPH_SNAPDIR) {
231 spin_lock(&ci->i_ceph_lock);
232 __ceph_get_fmode(ci, fmode);
233 spin_unlock(&ci->i_ceph_lock);
234 return ceph_init_file(inode, file, fmode);
235 }
236
237 /*
238 * No need to block if we have caps on the auth MDS (for
239 * write) or any MDS (for read). Update wanted set
240 * asynchronously.
241 */
242 spin_lock(&ci->i_ceph_lock);
243 if (__ceph_is_any_real_caps(ci) &&
244 (((fmode & CEPH_FILE_MODE_WR) == 0) || ci->i_auth_cap)) {
245 int mds_wanted = __ceph_caps_mds_wanted(ci);
246 int issued = __ceph_caps_issued(ci, NULL);
247
248 dout("open %p fmode %d want %s issued %s using existing\n",
249 inode, fmode, ceph_cap_string(wanted),
250 ceph_cap_string(issued));
251 __ceph_get_fmode(ci, fmode);
252 spin_unlock(&ci->i_ceph_lock);
253
254 /* adjust wanted? */
255 if ((issued & wanted) != wanted &&
256 (mds_wanted & wanted) != wanted &&
257 ceph_snap(inode) != CEPH_SNAPDIR)
258 ceph_check_caps(ci, 0, NULL);
259
260 return ceph_init_file(inode, file, fmode);
261 } else if (ceph_snap(inode) != CEPH_NOSNAP &&
262 (ci->i_snap_caps & wanted) == wanted) {
263 __ceph_get_fmode(ci, fmode);
264 spin_unlock(&ci->i_ceph_lock);
265 return ceph_init_file(inode, file, fmode);
266 }
267
268 spin_unlock(&ci->i_ceph_lock);
269
270 dout("open fmode %d wants %s\n", fmode, ceph_cap_string(wanted));
271 req = prepare_open_request(inode->i_sb, flags, 0);
272 if (IS_ERR(req)) {
273 err = PTR_ERR(req);
274 goto out;
275 }
276 req->r_inode = inode;
277 ihold(inode);
278
279 req->r_num_caps = 1;
280 err = ceph_mdsc_do_request(mdsc, NULL, req);
281 if (!err)
282 err = ceph_init_file(inode, file, req->r_fmode);
283 ceph_mdsc_put_request(req);
284 dout("open result=%d on %llx.%llx\n", err, ceph_vinop(inode));
285out:
286 return err;
287}
288
289
290/*
291 * Do a lookup + open with a single request. If we get a non-existent
292 * file or symlink, return 1 so the VFS can retry.
293 */
294int ceph_atomic_open(struct inode *dir, struct dentry *dentry,
295 struct file *file, unsigned flags, umode_t mode,
296 int *opened)
297{
298 struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
299 struct ceph_mds_client *mdsc = fsc->mdsc;
300 struct ceph_mds_request *req;
301 struct dentry *dn;
302 struct ceph_acls_info acls = {};
303 int mask;
304 int err;
305
306 dout("atomic_open %p dentry %p '%pd' %s flags %d mode 0%o\n",
307 dir, dentry, dentry,
308 d_unhashed(dentry) ? "unhashed" : "hashed", flags, mode);
309
310 if (dentry->d_name.len > NAME_MAX)
311 return -ENAMETOOLONG;
312
313 err = ceph_init_dentry(dentry);
314 if (err < 0)
315 return err;
316
317 if (flags & O_CREAT) {
318 err = ceph_pre_init_acls(dir, &mode, &acls);
319 if (err < 0)
320 return err;
321 }
322
323 /* do the open */
324 req = prepare_open_request(dir->i_sb, flags, mode);
325 if (IS_ERR(req)) {
326 err = PTR_ERR(req);
327 goto out_acl;
328 }
329 req->r_dentry = dget(dentry);
330 req->r_num_caps = 2;
331 if (flags & O_CREAT) {
332 req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
333 req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
334 if (acls.pagelist) {
335 req->r_pagelist = acls.pagelist;
336 acls.pagelist = NULL;
337 }
338 }
339
340 mask = CEPH_STAT_CAP_INODE | CEPH_CAP_AUTH_SHARED;
341 if (ceph_security_xattr_wanted(dir))
342 mask |= CEPH_CAP_XATTR_SHARED;
343 req->r_args.open.mask = cpu_to_le32(mask);
344
345 req->r_locked_dir = dir; /* caller holds dir->i_mutex */
346 err = ceph_mdsc_do_request(mdsc,
347 (flags & (O_CREAT|O_TRUNC)) ? dir : NULL,
348 req);
349 err = ceph_handle_snapdir(req, dentry, err);
350 if (err)
351 goto out_req;
352
353 if ((flags & O_CREAT) && !req->r_reply_info.head->is_dentry)
354 err = ceph_handle_notrace_create(dir, dentry);
355
356 if (d_unhashed(dentry)) {
357 dn = ceph_finish_lookup(req, dentry, err);
358 if (IS_ERR(dn))
359 err = PTR_ERR(dn);
360 } else {
361 /* we were given a hashed negative dentry */
362 dn = NULL;
363 }
364 if (err)
365 goto out_req;
366 if (dn || d_really_is_negative(dentry) || d_is_symlink(dentry)) {
367 /* make vfs retry on splice, ENOENT, or symlink */
368 dout("atomic_open finish_no_open on dn %p\n", dn);
369 err = finish_no_open(file, dn);
370 } else {
371 dout("atomic_open finish_open on dn %p\n", dn);
372 if (req->r_op == CEPH_MDS_OP_CREATE && req->r_reply_info.has_create_ino) {
373 ceph_init_inode_acls(d_inode(dentry), &acls);
374 *opened |= FILE_CREATED;
375 }
376 err = finish_open(file, dentry, ceph_open, opened);
377 }
378out_req:
379 if (!req->r_err && req->r_target_inode)
380 ceph_put_fmode(ceph_inode(req->r_target_inode), req->r_fmode);
381 ceph_mdsc_put_request(req);
382out_acl:
383 ceph_release_acls_info(&acls);
384 dout("atomic_open result=%d\n", err);
385 return err;
386}
387
388int ceph_release(struct inode *inode, struct file *file)
389{
390 struct ceph_inode_info *ci = ceph_inode(inode);
391 struct ceph_file_info *cf = file->private_data;
392
393 dout("release inode %p file %p\n", inode, file);
394 ceph_put_fmode(ci, cf->fmode);
395 if (cf->last_readdir)
396 ceph_mdsc_put_request(cf->last_readdir);
397 kfree(cf->last_name);
398 kfree(cf->dir_info);
399 kmem_cache_free(ceph_file_cachep, cf);
400
401 /* wake up anyone waiting for caps on this inode */
402 wake_up_all(&ci->i_cap_wq);
403 return 0;
404}
405
406enum {
407 HAVE_RETRIED = 1,
408 CHECK_EOF = 2,
409 READ_INLINE = 3,
410};
411
412/*
413 * Read a range of bytes striped over one or more objects. Iterate over
414 * objects we stripe over. (That's not atomic, but good enough for now.)
415 *
416 * If we get a short result from the OSD, check against i_size; we need to
417 * only return a short read to the caller if we hit EOF.
418 */
419static int striped_read(struct inode *inode,
420 u64 off, u64 len,
421 struct page **pages, int num_pages,
422 int *checkeof)
423{
424 struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
425 struct ceph_inode_info *ci = ceph_inode(inode);
426 u64 pos, this_len, left;
427 loff_t i_size;
428 int page_align, pages_left;
429 int read, ret;
430 struct page **page_pos;
431 bool hit_stripe, was_short;
432
433 /*
434 * we may need to do multiple reads. not atomic, unfortunately.
435 */
436 pos = off;
437 left = len;
438 page_pos = pages;
439 pages_left = num_pages;
440 read = 0;
441
442more:
443 page_align = pos & ~PAGE_MASK;
444 this_len = left;
445 ret = ceph_osdc_readpages(&fsc->client->osdc, ceph_vino(inode),
446 &ci->i_layout, pos, &this_len,
447 ci->i_truncate_seq,
448 ci->i_truncate_size,
449 page_pos, pages_left, page_align);
450 if (ret == -ENOENT)
451 ret = 0;
452 hit_stripe = this_len < left;
453 was_short = ret >= 0 && ret < this_len;
454 dout("striped_read %llu~%llu (read %u) got %d%s%s\n", pos, left, read,
455 ret, hit_stripe ? " HITSTRIPE" : "", was_short ? " SHORT" : "");
456
457 i_size = i_size_read(inode);
458 if (ret >= 0) {
459 int didpages;
460 if (was_short && (pos + ret < i_size)) {
461 int zlen = min(this_len - ret, i_size - pos - ret);
462 int zoff = (off & ~PAGE_MASK) + read + ret;
463 dout(" zero gap %llu to %llu\n",
464 pos + ret, pos + ret + zlen);
465 ceph_zero_page_vector_range(zoff, zlen, pages);
466 ret += zlen;
467 }
468
469 didpages = (page_align + ret) >> PAGE_SHIFT;
470 pos += ret;
471 read = pos - off;
472 left -= ret;
473 page_pos += didpages;
474 pages_left -= didpages;
475
476 /* hit stripe and need continue*/
477 if (left && hit_stripe && pos < i_size)
478 goto more;
479 }
480
481 if (read > 0) {
482 ret = read;
483 /* did we bounce off eof? */
484 if (pos + left > i_size)
485 *checkeof = CHECK_EOF;
486 }
487
488 dout("striped_read returns %d\n", ret);
489 return ret;
490}
491
492/*
493 * Completely synchronous read and write methods. Direct from __user
494 * buffer to osd, or directly to user pages (if O_DIRECT).
495 *
496 * If the read spans object boundary, just do multiple reads.
497 */
498static ssize_t ceph_sync_read(struct kiocb *iocb, struct iov_iter *i,
499 int *checkeof)
500{
501 struct file *file = iocb->ki_filp;
502 struct inode *inode = file_inode(file);
503 struct page **pages;
504 u64 off = iocb->ki_pos;
505 int num_pages, ret;
506 size_t len = iov_iter_count(i);
507
508 dout("sync_read on file %p %llu~%u %s\n", file, off,
509 (unsigned)len,
510 (file->f_flags & O_DIRECT) ? "O_DIRECT" : "");
511
512 if (!len)
513 return 0;
514 /*
515 * flush any page cache pages in this range. this
516 * will make concurrent normal and sync io slow,
517 * but it will at least behave sensibly when they are
518 * in sequence.
519 */
520 ret = filemap_write_and_wait_range(inode->i_mapping, off,
521 off + len);
522 if (ret < 0)
523 return ret;
524
525 num_pages = calc_pages_for(off, len);
526 pages = ceph_alloc_page_vector(num_pages, GFP_KERNEL);
527 if (IS_ERR(pages))
528 return PTR_ERR(pages);
529 ret = striped_read(inode, off, len, pages,
530 num_pages, checkeof);
531 if (ret > 0) {
532 int l, k = 0;
533 size_t left = ret;
534
535 while (left) {
536 size_t page_off = off & ~PAGE_MASK;
537 size_t copy = min_t(size_t, left,
538 PAGE_SIZE - page_off);
539 l = copy_page_to_iter(pages[k++], page_off, copy, i);
540 off += l;
541 left -= l;
542 if (l < copy)
543 break;
544 }
545 }
546 ceph_release_page_vector(pages, num_pages);
547
548 if (off > iocb->ki_pos) {
549 ret = off - iocb->ki_pos;
550 iocb->ki_pos = off;
551 }
552
553 dout("sync_read result %d\n", ret);
554 return ret;
555}
556
557struct ceph_aio_request {
558 struct kiocb *iocb;
559 size_t total_len;
560 int write;
561 int error;
562 struct list_head osd_reqs;
563 unsigned num_reqs;
564 atomic_t pending_reqs;
565 struct timespec mtime;
566 struct ceph_cap_flush *prealloc_cf;
567};
568
569struct ceph_aio_work {
570 struct work_struct work;
571 struct ceph_osd_request *req;
572};
573
574static void ceph_aio_retry_work(struct work_struct *work);
575
576static void ceph_aio_complete(struct inode *inode,
577 struct ceph_aio_request *aio_req)
578{
579 struct ceph_inode_info *ci = ceph_inode(inode);
580 int ret;
581
582 if (!atomic_dec_and_test(&aio_req->pending_reqs))
583 return;
584
585 ret = aio_req->error;
586 if (!ret)
587 ret = aio_req->total_len;
588
589 dout("ceph_aio_complete %p rc %d\n", inode, ret);
590
591 if (ret >= 0 && aio_req->write) {
592 int dirty;
593
594 loff_t endoff = aio_req->iocb->ki_pos + aio_req->total_len;
595 if (endoff > i_size_read(inode)) {
596 if (ceph_inode_set_size(inode, endoff))
597 ceph_check_caps(ci, CHECK_CAPS_AUTHONLY, NULL);
598 }
599
600 spin_lock(&ci->i_ceph_lock);
601 ci->i_inline_version = CEPH_INLINE_NONE;
602 dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_FILE_WR,
603 &aio_req->prealloc_cf);
604 spin_unlock(&ci->i_ceph_lock);
605 if (dirty)
606 __mark_inode_dirty(inode, dirty);
607
608 }
609
610 ceph_put_cap_refs(ci, (aio_req->write ? CEPH_CAP_FILE_WR :
611 CEPH_CAP_FILE_RD));
612
613 aio_req->iocb->ki_complete(aio_req->iocb, ret, 0);
614
615 ceph_free_cap_flush(aio_req->prealloc_cf);
616 kfree(aio_req);
617}
618
619static void ceph_aio_complete_req(struct ceph_osd_request *req,
620 struct ceph_msg *msg)
621{
622 int rc = req->r_result;
623 struct inode *inode = req->r_inode;
624 struct ceph_aio_request *aio_req = req->r_priv;
625 struct ceph_osd_data *osd_data = osd_req_op_extent_osd_data(req, 0);
626 int num_pages = calc_pages_for((u64)osd_data->alignment,
627 osd_data->length);
628
629 dout("ceph_aio_complete_req %p rc %d bytes %llu\n",
630 inode, rc, osd_data->length);
631
632 if (rc == -EOLDSNAPC) {
633 struct ceph_aio_work *aio_work;
634 BUG_ON(!aio_req->write);
635
636 aio_work = kmalloc(sizeof(*aio_work), GFP_NOFS);
637 if (aio_work) {
638 INIT_WORK(&aio_work->work, ceph_aio_retry_work);
639 aio_work->req = req;
640 queue_work(ceph_inode_to_client(inode)->wb_wq,
641 &aio_work->work);
642 return;
643 }
644 rc = -ENOMEM;
645 } else if (!aio_req->write) {
646 if (rc == -ENOENT)
647 rc = 0;
648 if (rc >= 0 && osd_data->length > rc) {
649 int zoff = osd_data->alignment + rc;
650 int zlen = osd_data->length - rc;
651 /*
652 * If read is satisfied by single OSD request,
653 * it can pass EOF. Otherwise read is within
654 * i_size.
655 */
656 if (aio_req->num_reqs == 1) {
657 loff_t i_size = i_size_read(inode);
658 loff_t endoff = aio_req->iocb->ki_pos + rc;
659 if (endoff < i_size)
660 zlen = min_t(size_t, zlen,
661 i_size - endoff);
662 aio_req->total_len = rc + zlen;
663 }
664
665 if (zlen > 0)
666 ceph_zero_page_vector_range(zoff, zlen,
667 osd_data->pages);
668 }
669 }
670
671 ceph_put_page_vector(osd_data->pages, num_pages, false);
672 ceph_osdc_put_request(req);
673
674 if (rc < 0)
675 cmpxchg(&aio_req->error, 0, rc);
676
677 ceph_aio_complete(inode, aio_req);
678 return;
679}
680
681static void ceph_aio_retry_work(struct work_struct *work)
682{
683 struct ceph_aio_work *aio_work =
684 container_of(work, struct ceph_aio_work, work);
685 struct ceph_osd_request *orig_req = aio_work->req;
686 struct ceph_aio_request *aio_req = orig_req->r_priv;
687 struct inode *inode = orig_req->r_inode;
688 struct ceph_inode_info *ci = ceph_inode(inode);
689 struct ceph_snap_context *snapc;
690 struct ceph_osd_request *req;
691 int ret;
692
693 spin_lock(&ci->i_ceph_lock);
694 if (__ceph_have_pending_cap_snap(ci)) {
695 struct ceph_cap_snap *capsnap =
696 list_last_entry(&ci->i_cap_snaps,
697 struct ceph_cap_snap,
698 ci_item);
699 snapc = ceph_get_snap_context(capsnap->context);
700 } else {
701 BUG_ON(!ci->i_head_snapc);
702 snapc = ceph_get_snap_context(ci->i_head_snapc);
703 }
704 spin_unlock(&ci->i_ceph_lock);
705
706 req = ceph_osdc_alloc_request(orig_req->r_osdc, snapc, 2,
707 false, GFP_NOFS);
708 if (!req) {
709 ret = -ENOMEM;
710 req = orig_req;
711 goto out;
712 }
713
714 req->r_flags = CEPH_OSD_FLAG_ORDERSNAP |
715 CEPH_OSD_FLAG_ONDISK |
716 CEPH_OSD_FLAG_WRITE;
717 req->r_base_oloc = orig_req->r_base_oloc;
718 req->r_base_oid = orig_req->r_base_oid;
719
720 req->r_ops[0] = orig_req->r_ops[0];
721 osd_req_op_init(req, 1, CEPH_OSD_OP_STARTSYNC, 0);
722
723 ceph_osdc_build_request(req, req->r_ops[0].extent.offset,
724 snapc, CEPH_NOSNAP, &aio_req->mtime);
725
726 ceph_osdc_put_request(orig_req);
727
728 req->r_callback = ceph_aio_complete_req;
729 req->r_inode = inode;
730 req->r_priv = aio_req;
731
732 ret = ceph_osdc_start_request(req->r_osdc, req, false);
733out:
734 if (ret < 0) {
735 req->r_result = ret;
736 ceph_aio_complete_req(req, NULL);
737 }
738
739 ceph_put_snap_context(snapc);
740 kfree(aio_work);
741}
742
743/*
744 * Write commit request unsafe callback, called to tell us when a
745 * request is unsafe (that is, in flight--has been handed to the
746 * messenger to send to its target osd). It is called again when
747 * we've received a response message indicating the request is
748 * "safe" (its CEPH_OSD_FLAG_ONDISK flag is set), or when a request
749 * is completed early (and unsuccessfully) due to a timeout or
750 * interrupt.
751 *
752 * This is used if we requested both an ACK and ONDISK commit reply
753 * from the OSD.
754 */
755static void ceph_sync_write_unsafe(struct ceph_osd_request *req, bool unsafe)
756{
757 struct ceph_inode_info *ci = ceph_inode(req->r_inode);
758
759 dout("%s %p tid %llu %ssafe\n", __func__, req, req->r_tid,
760 unsafe ? "un" : "");
761 if (unsafe) {
762 ceph_get_cap_refs(ci, CEPH_CAP_FILE_WR);
763 spin_lock(&ci->i_unsafe_lock);
764 list_add_tail(&req->r_unsafe_item,
765 &ci->i_unsafe_writes);
766 spin_unlock(&ci->i_unsafe_lock);
767 } else {
768 spin_lock(&ci->i_unsafe_lock);
769 list_del_init(&req->r_unsafe_item);
770 spin_unlock(&ci->i_unsafe_lock);
771 ceph_put_cap_refs(ci, CEPH_CAP_FILE_WR);
772 }
773}
774
775
776static ssize_t
777ceph_direct_read_write(struct kiocb *iocb, struct iov_iter *iter,
778 struct ceph_snap_context *snapc,
779 struct ceph_cap_flush **pcf)
780{
781 struct file *file = iocb->ki_filp;
782 struct inode *inode = file_inode(file);
783 struct ceph_inode_info *ci = ceph_inode(inode);
784 struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
785 struct ceph_vino vino;
786 struct ceph_osd_request *req;
787 struct page **pages;
788 struct ceph_aio_request *aio_req = NULL;
789 int num_pages = 0;
790 int flags;
791 int ret;
792 struct timespec mtime = current_fs_time(inode->i_sb);
793 size_t count = iov_iter_count(iter);
794 loff_t pos = iocb->ki_pos;
795 bool write = iov_iter_rw(iter) == WRITE;
796
797 if (write && ceph_snap(file_inode(file)) != CEPH_NOSNAP)
798 return -EROFS;
799
800 dout("sync_direct_read_write (%s) on file %p %lld~%u\n",
801 (write ? "write" : "read"), file, pos, (unsigned)count);
802
803 ret = filemap_write_and_wait_range(inode->i_mapping, pos, pos + count);
804 if (ret < 0)
805 return ret;
806
807 if (write) {
808 ret = invalidate_inode_pages2_range(inode->i_mapping,
809 pos >> PAGE_SHIFT,
810 (pos + count) >> PAGE_SHIFT);
811 if (ret < 0)
812 dout("invalidate_inode_pages2_range returned %d\n", ret);
813
814 flags = CEPH_OSD_FLAG_ORDERSNAP |
815 CEPH_OSD_FLAG_ONDISK |
816 CEPH_OSD_FLAG_WRITE;
817 } else {
818 flags = CEPH_OSD_FLAG_READ;
819 }
820
821 while (iov_iter_count(iter) > 0) {
822 u64 size = dio_get_pagev_size(iter);
823 size_t start = 0;
824 ssize_t len;
825
826 vino = ceph_vino(inode);
827 req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout,
828 vino, pos, &size, 0,
829 /*include a 'startsync' command*/
830 write ? 2 : 1,
831 write ? CEPH_OSD_OP_WRITE :
832 CEPH_OSD_OP_READ,
833 flags, snapc,
834 ci->i_truncate_seq,
835 ci->i_truncate_size,
836 false);
837 if (IS_ERR(req)) {
838 ret = PTR_ERR(req);
839 break;
840 }
841
842 len = size;
843 pages = dio_get_pages_alloc(iter, len, &start, &num_pages);
844 if (IS_ERR(pages)) {
845 ceph_osdc_put_request(req);
846 ret = PTR_ERR(pages);
847 break;
848 }
849
850 /*
851 * To simplify error handling, allow AIO when IO within i_size
852 * or IO can be satisfied by single OSD request.
853 */
854 if (pos == iocb->ki_pos && !is_sync_kiocb(iocb) &&
855 (len == count || pos + count <= i_size_read(inode))) {
856 aio_req = kzalloc(sizeof(*aio_req), GFP_KERNEL);
857 if (aio_req) {
858 aio_req->iocb = iocb;
859 aio_req->write = write;
860 INIT_LIST_HEAD(&aio_req->osd_reqs);
861 if (write) {
862 aio_req->mtime = mtime;
863 swap(aio_req->prealloc_cf, *pcf);
864 }
865 }
866 /* ignore error */
867 }
868
869 if (write) {
870 /*
871 * throw out any page cache pages in this range. this
872 * may block.
873 */
874 truncate_inode_pages_range(inode->i_mapping, pos,
875 (pos+len) | (PAGE_SIZE - 1));
876
877 osd_req_op_init(req, 1, CEPH_OSD_OP_STARTSYNC, 0);
878 }
879
880
881 osd_req_op_extent_osd_data_pages(req, 0, pages, len, start,
882 false, false);
883
884 ceph_osdc_build_request(req, pos, snapc, vino.snap, &mtime);
885
886 if (aio_req) {
887 aio_req->total_len += len;
888 aio_req->num_reqs++;
889 atomic_inc(&aio_req->pending_reqs);
890
891 req->r_callback = ceph_aio_complete_req;
892 req->r_inode = inode;
893 req->r_priv = aio_req;
894 list_add_tail(&req->r_unsafe_item, &aio_req->osd_reqs);
895
896 pos += len;
897 iov_iter_advance(iter, len);
898 continue;
899 }
900
901 ret = ceph_osdc_start_request(req->r_osdc, req, false);
902 if (!ret)
903 ret = ceph_osdc_wait_request(&fsc->client->osdc, req);
904
905 size = i_size_read(inode);
906 if (!write) {
907 if (ret == -ENOENT)
908 ret = 0;
909 if (ret >= 0 && ret < len && pos + ret < size) {
910 int zlen = min_t(size_t, len - ret,
911 size - pos - ret);
912 ceph_zero_page_vector_range(start + ret, zlen,
913 pages);
914 ret += zlen;
915 }
916 if (ret >= 0)
917 len = ret;
918 }
919
920 ceph_put_page_vector(pages, num_pages, false);
921
922 ceph_osdc_put_request(req);
923 if (ret < 0)
924 break;
925
926 pos += len;
927 iov_iter_advance(iter, len);
928
929 if (!write && pos >= size)
930 break;
931
932 if (write && pos > size) {
933 if (ceph_inode_set_size(inode, pos))
934 ceph_check_caps(ceph_inode(inode),
935 CHECK_CAPS_AUTHONLY,
936 NULL);
937 }
938 }
939
940 if (aio_req) {
941 if (aio_req->num_reqs == 0) {
942 kfree(aio_req);
943 return ret;
944 }
945
946 ceph_get_cap_refs(ci, write ? CEPH_CAP_FILE_WR :
947 CEPH_CAP_FILE_RD);
948
949 while (!list_empty(&aio_req->osd_reqs)) {
950 req = list_first_entry(&aio_req->osd_reqs,
951 struct ceph_osd_request,
952 r_unsafe_item);
953 list_del_init(&req->r_unsafe_item);
954 if (ret >= 0)
955 ret = ceph_osdc_start_request(req->r_osdc,
956 req, false);
957 if (ret < 0) {
958 req->r_result = ret;
959 ceph_aio_complete_req(req, NULL);
960 }
961 }
962 return -EIOCBQUEUED;
963 }
964
965 if (ret != -EOLDSNAPC && pos > iocb->ki_pos) {
966 ret = pos - iocb->ki_pos;
967 iocb->ki_pos = pos;
968 }
969 return ret;
970}
971
972/*
973 * Synchronous write, straight from __user pointer or user pages.
974 *
975 * If write spans object boundary, just do multiple writes. (For a
976 * correct atomic write, we should e.g. take write locks on all
977 * objects, rollback on failure, etc.)
978 */
979static ssize_t
980ceph_sync_write(struct kiocb *iocb, struct iov_iter *from, loff_t pos,
981 struct ceph_snap_context *snapc)
982{
983 struct file *file = iocb->ki_filp;
984 struct inode *inode = file_inode(file);
985 struct ceph_inode_info *ci = ceph_inode(inode);
986 struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
987 struct ceph_vino vino;
988 struct ceph_osd_request *req;
989 struct page **pages;
990 u64 len;
991 int num_pages;
992 int written = 0;
993 int flags;
994 int check_caps = 0;
995 int ret;
996 struct timespec mtime = current_fs_time(inode->i_sb);
997 size_t count = iov_iter_count(from);
998
999 if (ceph_snap(file_inode(file)) != CEPH_NOSNAP)
1000 return -EROFS;
1001
1002 dout("sync_write on file %p %lld~%u\n", file, pos, (unsigned)count);
1003
1004 ret = filemap_write_and_wait_range(inode->i_mapping, pos, pos + count);
1005 if (ret < 0)
1006 return ret;
1007
1008 ret = invalidate_inode_pages2_range(inode->i_mapping,
1009 pos >> PAGE_SHIFT,
1010 (pos + count) >> PAGE_SHIFT);
1011 if (ret < 0)
1012 dout("invalidate_inode_pages2_range returned %d\n", ret);
1013
1014 flags = CEPH_OSD_FLAG_ORDERSNAP |
1015 CEPH_OSD_FLAG_ONDISK |
1016 CEPH_OSD_FLAG_WRITE |
1017 CEPH_OSD_FLAG_ACK;
1018
1019 while ((len = iov_iter_count(from)) > 0) {
1020 size_t left;
1021 int n;
1022
1023 vino = ceph_vino(inode);
1024 req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout,
1025 vino, pos, &len, 0, 1,
1026 CEPH_OSD_OP_WRITE, flags, snapc,
1027 ci->i_truncate_seq,
1028 ci->i_truncate_size,
1029 false);
1030 if (IS_ERR(req)) {
1031 ret = PTR_ERR(req);
1032 break;
1033 }
1034
1035 /*
1036 * write from beginning of first page,
1037 * regardless of io alignment
1038 */
1039 num_pages = (len + PAGE_SIZE - 1) >> PAGE_SHIFT;
1040
1041 pages = ceph_alloc_page_vector(num_pages, GFP_KERNEL);
1042 if (IS_ERR(pages)) {
1043 ret = PTR_ERR(pages);
1044 goto out;
1045 }
1046
1047 left = len;
1048 for (n = 0; n < num_pages; n++) {
1049 size_t plen = min_t(size_t, left, PAGE_SIZE);
1050 ret = copy_page_from_iter(pages[n], 0, plen, from);
1051 if (ret != plen) {
1052 ret = -EFAULT;
1053 break;
1054 }
1055 left -= ret;
1056 }
1057
1058 if (ret < 0) {
1059 ceph_release_page_vector(pages, num_pages);
1060 goto out;
1061 }
1062
1063 /* get a second commit callback */
1064 req->r_unsafe_callback = ceph_sync_write_unsafe;
1065 req->r_inode = inode;
1066
1067 osd_req_op_extent_osd_data_pages(req, 0, pages, len, 0,
1068 false, true);
1069
1070 /* BUG_ON(vino.snap != CEPH_NOSNAP); */
1071 ceph_osdc_build_request(req, pos, snapc, vino.snap, &mtime);
1072
1073 ret = ceph_osdc_start_request(&fsc->client->osdc, req, false);
1074 if (!ret)
1075 ret = ceph_osdc_wait_request(&fsc->client->osdc, req);
1076
1077out:
1078 ceph_osdc_put_request(req);
1079 if (ret == 0) {
1080 pos += len;
1081 written += len;
1082
1083 if (pos > i_size_read(inode)) {
1084 check_caps = ceph_inode_set_size(inode, pos);
1085 if (check_caps)
1086 ceph_check_caps(ceph_inode(inode),
1087 CHECK_CAPS_AUTHONLY,
1088 NULL);
1089 }
1090 } else
1091 break;
1092 }
1093
1094 if (ret != -EOLDSNAPC && written > 0) {
1095 ret = written;
1096 iocb->ki_pos = pos;
1097 }
1098 return ret;
1099}
1100
1101/*
1102 * Wrap generic_file_aio_read with checks for cap bits on the inode.
1103 * Atomically grab references, so that those bits are not released
1104 * back to the MDS mid-read.
1105 *
1106 * Hmm, the sync read case isn't actually async... should it be?
1107 */
1108static ssize_t ceph_read_iter(struct kiocb *iocb, struct iov_iter *to)
1109{
1110 struct file *filp = iocb->ki_filp;
1111 struct ceph_file_info *fi = filp->private_data;
1112 size_t len = iov_iter_count(to);
1113 struct inode *inode = file_inode(filp);
1114 struct ceph_inode_info *ci = ceph_inode(inode);
1115 struct page *pinned_page = NULL;
1116 ssize_t ret;
1117 int want, got = 0;
1118 int retry_op = 0, read = 0;
1119
1120again:
1121 dout("aio_read %p %llx.%llx %llu~%u trying to get caps on %p\n",
1122 inode, ceph_vinop(inode), iocb->ki_pos, (unsigned)len, inode);
1123
1124 if (fi->fmode & CEPH_FILE_MODE_LAZY)
1125 want = CEPH_CAP_FILE_CACHE | CEPH_CAP_FILE_LAZYIO;
1126 else
1127 want = CEPH_CAP_FILE_CACHE;
1128 ret = ceph_get_caps(ci, CEPH_CAP_FILE_RD, want, -1, &got, &pinned_page);
1129 if (ret < 0)
1130 return ret;
1131
1132 if ((got & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)) == 0 ||
1133 (iocb->ki_flags & IOCB_DIRECT) ||
1134 (fi->flags & CEPH_F_SYNC)) {
1135
1136 dout("aio_sync_read %p %llx.%llx %llu~%u got cap refs on %s\n",
1137 inode, ceph_vinop(inode), iocb->ki_pos, (unsigned)len,
1138 ceph_cap_string(got));
1139
1140 if (ci->i_inline_version == CEPH_INLINE_NONE) {
1141 if (!retry_op && (iocb->ki_flags & IOCB_DIRECT)) {
1142 ret = ceph_direct_read_write(iocb, to,
1143 NULL, NULL);
1144 if (ret >= 0 && ret < len)
1145 retry_op = CHECK_EOF;
1146 } else {
1147 ret = ceph_sync_read(iocb, to, &retry_op);
1148 }
1149 } else {
1150 retry_op = READ_INLINE;
1151 }
1152 } else {
1153 dout("aio_read %p %llx.%llx %llu~%u got cap refs on %s\n",
1154 inode, ceph_vinop(inode), iocb->ki_pos, (unsigned)len,
1155 ceph_cap_string(got));
1156
1157 ret = generic_file_read_iter(iocb, to);
1158 }
1159 dout("aio_read %p %llx.%llx dropping cap refs on %s = %d\n",
1160 inode, ceph_vinop(inode), ceph_cap_string(got), (int)ret);
1161 if (pinned_page) {
1162 put_page(pinned_page);
1163 pinned_page = NULL;
1164 }
1165 ceph_put_cap_refs(ci, got);
1166 if (retry_op > HAVE_RETRIED && ret >= 0) {
1167 int statret;
1168 struct page *page = NULL;
1169 loff_t i_size;
1170 if (retry_op == READ_INLINE) {
1171 page = __page_cache_alloc(GFP_KERNEL);
1172 if (!page)
1173 return -ENOMEM;
1174 }
1175
1176 statret = __ceph_do_getattr(inode, page,
1177 CEPH_STAT_CAP_INLINE_DATA, !!page);
1178 if (statret < 0) {
1179 __free_page(page);
1180 if (statret == -ENODATA) {
1181 BUG_ON(retry_op != READ_INLINE);
1182 goto again;
1183 }
1184 return statret;
1185 }
1186
1187 i_size = i_size_read(inode);
1188 if (retry_op == READ_INLINE) {
1189 BUG_ON(ret > 0 || read > 0);
1190 if (iocb->ki_pos < i_size &&
1191 iocb->ki_pos < PAGE_SIZE) {
1192 loff_t end = min_t(loff_t, i_size,
1193 iocb->ki_pos + len);
1194 end = min_t(loff_t, end, PAGE_SIZE);
1195 if (statret < end)
1196 zero_user_segment(page, statret, end);
1197 ret = copy_page_to_iter(page,
1198 iocb->ki_pos & ~PAGE_MASK,
1199 end - iocb->ki_pos, to);
1200 iocb->ki_pos += ret;
1201 read += ret;
1202 }
1203 if (iocb->ki_pos < i_size && read < len) {
1204 size_t zlen = min_t(size_t, len - read,
1205 i_size - iocb->ki_pos);
1206 ret = iov_iter_zero(zlen, to);
1207 iocb->ki_pos += ret;
1208 read += ret;
1209 }
1210 __free_pages(page, 0);
1211 return read;
1212 }
1213
1214 /* hit EOF or hole? */
1215 if (retry_op == CHECK_EOF && iocb->ki_pos < i_size &&
1216 ret < len) {
1217 dout("sync_read hit hole, ppos %lld < size %lld"
1218 ", reading more\n", iocb->ki_pos, i_size);
1219
1220 read += ret;
1221 len -= ret;
1222 retry_op = HAVE_RETRIED;
1223 goto again;
1224 }
1225 }
1226
1227 if (ret >= 0)
1228 ret += read;
1229
1230 return ret;
1231}
1232
1233/*
1234 * Take cap references to avoid releasing caps to MDS mid-write.
1235 *
1236 * If we are synchronous, and write with an old snap context, the OSD
1237 * may return EOLDSNAPC. In that case, retry the write.. _after_
1238 * dropping our cap refs and allowing the pending snap to logically
1239 * complete _before_ this write occurs.
1240 *
1241 * If we are near ENOSPC, write synchronously.
1242 */
1243static ssize_t ceph_write_iter(struct kiocb *iocb, struct iov_iter *from)
1244{
1245 struct file *file = iocb->ki_filp;
1246 struct ceph_file_info *fi = file->private_data;
1247 struct inode *inode = file_inode(file);
1248 struct ceph_inode_info *ci = ceph_inode(inode);
1249 struct ceph_osd_client *osdc =
1250 &ceph_sb_to_client(inode->i_sb)->client->osdc;
1251 struct ceph_cap_flush *prealloc_cf;
1252 ssize_t count, written = 0;
1253 int err, want, got;
1254 loff_t pos;
1255
1256 if (ceph_snap(inode) != CEPH_NOSNAP)
1257 return -EROFS;
1258
1259 prealloc_cf = ceph_alloc_cap_flush();
1260 if (!prealloc_cf)
1261 return -ENOMEM;
1262
1263 inode_lock(inode);
1264
1265 /* We can write back this queue in page reclaim */
1266 current->backing_dev_info = inode_to_bdi(inode);
1267
1268 if (iocb->ki_flags & IOCB_APPEND) {
1269 err = ceph_do_getattr(inode, CEPH_STAT_CAP_SIZE, false);
1270 if (err < 0)
1271 goto out;
1272 }
1273
1274 err = generic_write_checks(iocb, from);
1275 if (err <= 0)
1276 goto out;
1277
1278 pos = iocb->ki_pos;
1279 count = iov_iter_count(from);
1280 err = file_remove_privs(file);
1281 if (err)
1282 goto out;
1283
1284 err = file_update_time(file);
1285 if (err)
1286 goto out;
1287
1288 if (ci->i_inline_version != CEPH_INLINE_NONE) {
1289 err = ceph_uninline_data(file, NULL);
1290 if (err < 0)
1291 goto out;
1292 }
1293
1294retry_snap:
1295 if (ceph_osdmap_flag(osdc->osdmap, CEPH_OSDMAP_FULL)) {
1296 err = -ENOSPC;
1297 goto out;
1298 }
1299
1300 dout("aio_write %p %llx.%llx %llu~%zd getting caps. i_size %llu\n",
1301 inode, ceph_vinop(inode), pos, count, i_size_read(inode));
1302 if (fi->fmode & CEPH_FILE_MODE_LAZY)
1303 want = CEPH_CAP_FILE_BUFFER | CEPH_CAP_FILE_LAZYIO;
1304 else
1305 want = CEPH_CAP_FILE_BUFFER;
1306 got = 0;
1307 err = ceph_get_caps(ci, CEPH_CAP_FILE_WR, want, pos + count,
1308 &got, NULL);
1309 if (err < 0)
1310 goto out;
1311
1312 dout("aio_write %p %llx.%llx %llu~%zd got cap refs on %s\n",
1313 inode, ceph_vinop(inode), pos, count, ceph_cap_string(got));
1314
1315 if ((got & (CEPH_CAP_FILE_BUFFER|CEPH_CAP_FILE_LAZYIO)) == 0 ||
1316 (iocb->ki_flags & IOCB_DIRECT) || (fi->flags & CEPH_F_SYNC)) {
1317 struct ceph_snap_context *snapc;
1318 struct iov_iter data;
1319 inode_unlock(inode);
1320
1321 spin_lock(&ci->i_ceph_lock);
1322 if (__ceph_have_pending_cap_snap(ci)) {
1323 struct ceph_cap_snap *capsnap =
1324 list_last_entry(&ci->i_cap_snaps,
1325 struct ceph_cap_snap,
1326 ci_item);
1327 snapc = ceph_get_snap_context(capsnap->context);
1328 } else {
1329 BUG_ON(!ci->i_head_snapc);
1330 snapc = ceph_get_snap_context(ci->i_head_snapc);
1331 }
1332 spin_unlock(&ci->i_ceph_lock);
1333
1334 /* we might need to revert back to that point */
1335 data = *from;
1336 if (iocb->ki_flags & IOCB_DIRECT)
1337 written = ceph_direct_read_write(iocb, &data, snapc,
1338 &prealloc_cf);
1339 else
1340 written = ceph_sync_write(iocb, &data, pos, snapc);
1341 if (written == -EOLDSNAPC) {
1342 dout("aio_write %p %llx.%llx %llu~%u"
1343 "got EOLDSNAPC, retrying\n",
1344 inode, ceph_vinop(inode),
1345 pos, (unsigned)count);
1346 inode_lock(inode);
1347 goto retry_snap;
1348 }
1349 if (written > 0)
1350 iov_iter_advance(from, written);
1351 ceph_put_snap_context(snapc);
1352 } else {
1353 loff_t old_size = i_size_read(inode);
1354 /*
1355 * No need to acquire the i_truncate_mutex. Because
1356 * the MDS revokes Fwb caps before sending truncate
1357 * message to us. We can't get Fwb cap while there
1358 * are pending vmtruncate. So write and vmtruncate
1359 * can not run at the same time
1360 */
1361 written = generic_perform_write(file, from, pos);
1362 if (likely(written >= 0))
1363 iocb->ki_pos = pos + written;
1364 if (i_size_read(inode) > old_size)
1365 ceph_fscache_update_objectsize(inode);
1366 inode_unlock(inode);
1367 }
1368
1369 if (written >= 0) {
1370 int dirty;
1371 spin_lock(&ci->i_ceph_lock);
1372 ci->i_inline_version = CEPH_INLINE_NONE;
1373 dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_FILE_WR,
1374 &prealloc_cf);
1375 spin_unlock(&ci->i_ceph_lock);
1376 if (dirty)
1377 __mark_inode_dirty(inode, dirty);
1378 }
1379
1380 dout("aio_write %p %llx.%llx %llu~%u dropping cap refs on %s\n",
1381 inode, ceph_vinop(inode), pos, (unsigned)count,
1382 ceph_cap_string(got));
1383 ceph_put_cap_refs(ci, got);
1384
1385 if (written >= 0 &&
1386 ((file->f_flags & O_SYNC) || IS_SYNC(file->f_mapping->host) ||
1387 ceph_osdmap_flag(osdc->osdmap, CEPH_OSDMAP_NEARFULL))) {
1388 err = vfs_fsync_range(file, pos, pos + written - 1, 1);
1389 if (err < 0)
1390 written = err;
1391 }
1392
1393 goto out_unlocked;
1394
1395out:
1396 inode_unlock(inode);
1397out_unlocked:
1398 ceph_free_cap_flush(prealloc_cf);
1399 current->backing_dev_info = NULL;
1400 return written ? written : err;
1401}
1402
1403/*
1404 * llseek. be sure to verify file size on SEEK_END.
1405 */
1406static loff_t ceph_llseek(struct file *file, loff_t offset, int whence)
1407{
1408 struct inode *inode = file->f_mapping->host;
1409 loff_t i_size;
1410 int ret;
1411
1412 inode_lock(inode);
1413
1414 if (whence == SEEK_END || whence == SEEK_DATA || whence == SEEK_HOLE) {
1415 ret = ceph_do_getattr(inode, CEPH_STAT_CAP_SIZE, false);
1416 if (ret < 0) {
1417 offset = ret;
1418 goto out;
1419 }
1420 }
1421
1422 i_size = i_size_read(inode);
1423 switch (whence) {
1424 case SEEK_END:
1425 offset += i_size;
1426 break;
1427 case SEEK_CUR:
1428 /*
1429 * Here we special-case the lseek(fd, 0, SEEK_CUR)
1430 * position-querying operation. Avoid rewriting the "same"
1431 * f_pos value back to the file because a concurrent read(),
1432 * write() or lseek() might have altered it
1433 */
1434 if (offset == 0) {
1435 offset = file->f_pos;
1436 goto out;
1437 }
1438 offset += file->f_pos;
1439 break;
1440 case SEEK_DATA:
1441 if (offset >= i_size) {
1442 ret = -ENXIO;
1443 goto out;
1444 }
1445 break;
1446 case SEEK_HOLE:
1447 if (offset >= i_size) {
1448 ret = -ENXIO;
1449 goto out;
1450 }
1451 offset = i_size;
1452 break;
1453 }
1454
1455 offset = vfs_setpos(file, offset, inode->i_sb->s_maxbytes);
1456
1457out:
1458 inode_unlock(inode);
1459 return offset;
1460}
1461
1462static inline void ceph_zero_partial_page(
1463 struct inode *inode, loff_t offset, unsigned size)
1464{
1465 struct page *page;
1466 pgoff_t index = offset >> PAGE_SHIFT;
1467
1468 page = find_lock_page(inode->i_mapping, index);
1469 if (page) {
1470 wait_on_page_writeback(page);
1471 zero_user(page, offset & (PAGE_SIZE - 1), size);
1472 unlock_page(page);
1473 put_page(page);
1474 }
1475}
1476
1477static void ceph_zero_pagecache_range(struct inode *inode, loff_t offset,
1478 loff_t length)
1479{
1480 loff_t nearly = round_up(offset, PAGE_SIZE);
1481 if (offset < nearly) {
1482 loff_t size = nearly - offset;
1483 if (length < size)
1484 size = length;
1485 ceph_zero_partial_page(inode, offset, size);
1486 offset += size;
1487 length -= size;
1488 }
1489 if (length >= PAGE_SIZE) {
1490 loff_t size = round_down(length, PAGE_SIZE);
1491 truncate_pagecache_range(inode, offset, offset + size - 1);
1492 offset += size;
1493 length -= size;
1494 }
1495 if (length)
1496 ceph_zero_partial_page(inode, offset, length);
1497}
1498
1499static int ceph_zero_partial_object(struct inode *inode,
1500 loff_t offset, loff_t *length)
1501{
1502 struct ceph_inode_info *ci = ceph_inode(inode);
1503 struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
1504 struct ceph_osd_request *req;
1505 int ret = 0;
1506 loff_t zero = 0;
1507 int op;
1508
1509 if (!length) {
1510 op = offset ? CEPH_OSD_OP_DELETE : CEPH_OSD_OP_TRUNCATE;
1511 length = &zero;
1512 } else {
1513 op = CEPH_OSD_OP_ZERO;
1514 }
1515
1516 req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout,
1517 ceph_vino(inode),
1518 offset, length,
1519 0, 1, op,
1520 CEPH_OSD_FLAG_WRITE |
1521 CEPH_OSD_FLAG_ONDISK,
1522 NULL, 0, 0, false);
1523 if (IS_ERR(req)) {
1524 ret = PTR_ERR(req);
1525 goto out;
1526 }
1527
1528 ceph_osdc_build_request(req, offset, NULL, ceph_vino(inode).snap,
1529 &inode->i_mtime);
1530
1531 ret = ceph_osdc_start_request(&fsc->client->osdc, req, false);
1532 if (!ret) {
1533 ret = ceph_osdc_wait_request(&fsc->client->osdc, req);
1534 if (ret == -ENOENT)
1535 ret = 0;
1536 }
1537 ceph_osdc_put_request(req);
1538
1539out:
1540 return ret;
1541}
1542
1543static int ceph_zero_objects(struct inode *inode, loff_t offset, loff_t length)
1544{
1545 int ret = 0;
1546 struct ceph_inode_info *ci = ceph_inode(inode);
1547 s32 stripe_unit = ceph_file_layout_su(ci->i_layout);
1548 s32 stripe_count = ceph_file_layout_stripe_count(ci->i_layout);
1549 s32 object_size = ceph_file_layout_object_size(ci->i_layout);
1550 u64 object_set_size = object_size * stripe_count;
1551 u64 nearly, t;
1552
1553 /* round offset up to next period boundary */
1554 nearly = offset + object_set_size - 1;
1555 t = nearly;
1556 nearly -= do_div(t, object_set_size);
1557
1558 while (length && offset < nearly) {
1559 loff_t size = length;
1560 ret = ceph_zero_partial_object(inode, offset, &size);
1561 if (ret < 0)
1562 return ret;
1563 offset += size;
1564 length -= size;
1565 }
1566 while (length >= object_set_size) {
1567 int i;
1568 loff_t pos = offset;
1569 for (i = 0; i < stripe_count; ++i) {
1570 ret = ceph_zero_partial_object(inode, pos, NULL);
1571 if (ret < 0)
1572 return ret;
1573 pos += stripe_unit;
1574 }
1575 offset += object_set_size;
1576 length -= object_set_size;
1577 }
1578 while (length) {
1579 loff_t size = length;
1580 ret = ceph_zero_partial_object(inode, offset, &size);
1581 if (ret < 0)
1582 return ret;
1583 offset += size;
1584 length -= size;
1585 }
1586 return ret;
1587}
1588
1589static long ceph_fallocate(struct file *file, int mode,
1590 loff_t offset, loff_t length)
1591{
1592 struct ceph_file_info *fi = file->private_data;
1593 struct inode *inode = file_inode(file);
1594 struct ceph_inode_info *ci = ceph_inode(inode);
1595 struct ceph_osd_client *osdc =
1596 &ceph_inode_to_client(inode)->client->osdc;
1597 struct ceph_cap_flush *prealloc_cf;
1598 int want, got = 0;
1599 int dirty;
1600 int ret = 0;
1601 loff_t endoff = 0;
1602 loff_t size;
1603
1604 if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE))
1605 return -EOPNOTSUPP;
1606
1607 if (!S_ISREG(inode->i_mode))
1608 return -EOPNOTSUPP;
1609
1610 prealloc_cf = ceph_alloc_cap_flush();
1611 if (!prealloc_cf)
1612 return -ENOMEM;
1613
1614 inode_lock(inode);
1615
1616 if (ceph_snap(inode) != CEPH_NOSNAP) {
1617 ret = -EROFS;
1618 goto unlock;
1619 }
1620
1621 if (ceph_osdmap_flag(osdc->osdmap, CEPH_OSDMAP_FULL) &&
1622 !(mode & FALLOC_FL_PUNCH_HOLE)) {
1623 ret = -ENOSPC;
1624 goto unlock;
1625 }
1626
1627 if (ci->i_inline_version != CEPH_INLINE_NONE) {
1628 ret = ceph_uninline_data(file, NULL);
1629 if (ret < 0)
1630 goto unlock;
1631 }
1632
1633 size = i_size_read(inode);
1634 if (!(mode & FALLOC_FL_KEEP_SIZE))
1635 endoff = offset + length;
1636
1637 if (fi->fmode & CEPH_FILE_MODE_LAZY)
1638 want = CEPH_CAP_FILE_BUFFER | CEPH_CAP_FILE_LAZYIO;
1639 else
1640 want = CEPH_CAP_FILE_BUFFER;
1641
1642 ret = ceph_get_caps(ci, CEPH_CAP_FILE_WR, want, endoff, &got, NULL);
1643 if (ret < 0)
1644 goto unlock;
1645
1646 if (mode & FALLOC_FL_PUNCH_HOLE) {
1647 if (offset < size)
1648 ceph_zero_pagecache_range(inode, offset, length);
1649 ret = ceph_zero_objects(inode, offset, length);
1650 } else if (endoff > size) {
1651 truncate_pagecache_range(inode, size, -1);
1652 if (ceph_inode_set_size(inode, endoff))
1653 ceph_check_caps(ceph_inode(inode),
1654 CHECK_CAPS_AUTHONLY, NULL);
1655 }
1656
1657 if (!ret) {
1658 spin_lock(&ci->i_ceph_lock);
1659 ci->i_inline_version = CEPH_INLINE_NONE;
1660 dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_FILE_WR,
1661 &prealloc_cf);
1662 spin_unlock(&ci->i_ceph_lock);
1663 if (dirty)
1664 __mark_inode_dirty(inode, dirty);
1665 }
1666
1667 ceph_put_cap_refs(ci, got);
1668unlock:
1669 inode_unlock(inode);
1670 ceph_free_cap_flush(prealloc_cf);
1671 return ret;
1672}
1673
1674const struct file_operations ceph_file_fops = {
1675 .open = ceph_open,
1676 .release = ceph_release,
1677 .llseek = ceph_llseek,
1678 .read_iter = ceph_read_iter,
1679 .write_iter = ceph_write_iter,
1680 .mmap = ceph_mmap,
1681 .fsync = ceph_fsync,
1682 .lock = ceph_lock,
1683 .flock = ceph_flock,
1684 .splice_read = generic_file_splice_read,
1685 .splice_write = iter_file_splice_write,
1686 .unlocked_ioctl = ceph_ioctl,
1687 .compat_ioctl = ceph_ioctl,
1688 .fallocate = ceph_fallocate,
1689};
1690
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 */
43static struct ceph_mds_request *
44prepare_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);
61out:
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 */
69static 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 */
132int 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));
221out:
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 */
230int 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 }
294out_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
302int 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 */
328static 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
354more:
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 */
413static 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 = i->count;
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 void __user *data = i->iov[0].iov_base + i->iov_offset;
440 size_t len = i->iov[0].iov_len - i->iov_offset;
441
442 num_pages = calc_pages_for((unsigned long)data, len);
443 pages = ceph_get_direct_page_vector(data,
444 num_pages, true);
445 if (IS_ERR(pages))
446 return PTR_ERR(pages);
447
448 ret = striped_read(inode, off, len,
449 pages, num_pages, checkeof,
450 1, (unsigned long)data & ~PAGE_MASK);
451 ceph_put_page_vector(pages, num_pages, true);
452
453 if (ret <= 0)
454 break;
455 off += ret;
456 iov_iter_advance(i, ret);
457 if (ret < len)
458 break;
459 }
460 } else {
461 num_pages = calc_pages_for(off, len);
462 pages = ceph_alloc_page_vector(num_pages, GFP_NOFS);
463 if (IS_ERR(pages))
464 return PTR_ERR(pages);
465 ret = striped_read(inode, off, len, pages,
466 num_pages, checkeof, 0, 0);
467 if (ret > 0) {
468 int l, k = 0;
469 size_t left = len = ret;
470
471 while (left) {
472 void __user *data = i->iov[0].iov_base
473 + i->iov_offset;
474 l = min(i->iov[0].iov_len - i->iov_offset,
475 left);
476
477 ret = ceph_copy_page_vector_to_user(&pages[k],
478 data, off,
479 l);
480 if (ret > 0) {
481 iov_iter_advance(i, ret);
482 left -= ret;
483 off += ret;
484 k = calc_pages_for(iocb->ki_pos,
485 len - left + 1) - 1;
486 BUG_ON(k >= num_pages && left);
487 } else
488 break;
489 }
490 }
491 ceph_release_page_vector(pages, num_pages);
492 }
493
494 if (off > iocb->ki_pos) {
495 ret = off - iocb->ki_pos;
496 iocb->ki_pos = off;
497 }
498
499 dout("sync_read result %d\n", ret);
500 return ret;
501}
502
503/*
504 * Write commit request unsafe callback, called to tell us when a
505 * request is unsafe (that is, in flight--has been handed to the
506 * messenger to send to its target osd). It is called again when
507 * we've received a response message indicating the request is
508 * "safe" (its CEPH_OSD_FLAG_ONDISK flag is set), or when a request
509 * is completed early (and unsuccessfully) due to a timeout or
510 * interrupt.
511 *
512 * This is used if we requested both an ACK and ONDISK commit reply
513 * from the OSD.
514 */
515static void ceph_sync_write_unsafe(struct ceph_osd_request *req, bool unsafe)
516{
517 struct ceph_inode_info *ci = ceph_inode(req->r_inode);
518
519 dout("%s %p tid %llu %ssafe\n", __func__, req, req->r_tid,
520 unsafe ? "un" : "");
521 if (unsafe) {
522 ceph_get_cap_refs(ci, CEPH_CAP_FILE_WR);
523 spin_lock(&ci->i_unsafe_lock);
524 list_add_tail(&req->r_unsafe_item,
525 &ci->i_unsafe_writes);
526 spin_unlock(&ci->i_unsafe_lock);
527 } else {
528 spin_lock(&ci->i_unsafe_lock);
529 list_del_init(&req->r_unsafe_item);
530 spin_unlock(&ci->i_unsafe_lock);
531 ceph_put_cap_refs(ci, CEPH_CAP_FILE_WR);
532 }
533}
534
535
536/*
537 * Synchronous write, straight from __user pointer or user pages.
538 *
539 * If write spans object boundary, just do multiple writes. (For a
540 * correct atomic write, we should e.g. take write locks on all
541 * objects, rollback on failure, etc.)
542 */
543static ssize_t
544ceph_sync_direct_write(struct kiocb *iocb, const struct iovec *iov,
545 unsigned long nr_segs, size_t count)
546{
547 struct file *file = iocb->ki_filp;
548 struct inode *inode = file_inode(file);
549 struct ceph_inode_info *ci = ceph_inode(inode);
550 struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
551 struct ceph_snap_context *snapc;
552 struct ceph_vino vino;
553 struct ceph_osd_request *req;
554 struct page **pages;
555 int num_pages;
556 int written = 0;
557 int flags;
558 int check_caps = 0;
559 int page_align;
560 int ret;
561 struct timespec mtime = CURRENT_TIME;
562 loff_t pos = iocb->ki_pos;
563 struct iov_iter i;
564
565 if (ceph_snap(file_inode(file)) != CEPH_NOSNAP)
566 return -EROFS;
567
568 dout("sync_direct_write on file %p %lld~%u\n", file, pos,
569 (unsigned)count);
570
571 ret = filemap_write_and_wait_range(inode->i_mapping, pos, pos + count);
572 if (ret < 0)
573 return ret;
574
575 ret = invalidate_inode_pages2_range(inode->i_mapping,
576 pos >> PAGE_CACHE_SHIFT,
577 (pos + count) >> PAGE_CACHE_SHIFT);
578 if (ret < 0)
579 dout("invalidate_inode_pages2_range returned %d\n", ret);
580
581 flags = CEPH_OSD_FLAG_ORDERSNAP |
582 CEPH_OSD_FLAG_ONDISK |
583 CEPH_OSD_FLAG_WRITE;
584
585 iov_iter_init(&i, iov, nr_segs, count, 0);
586
587 while (iov_iter_count(&i) > 0) {
588 void __user *data = i.iov->iov_base + i.iov_offset;
589 u64 len = i.iov->iov_len - i.iov_offset;
590
591 page_align = (unsigned long)data & ~PAGE_MASK;
592
593 snapc = ci->i_snap_realm->cached_context;
594 vino = ceph_vino(inode);
595 req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout,
596 vino, pos, &len,
597 2,/*include a 'startsync' command*/
598 CEPH_OSD_OP_WRITE, flags, snapc,
599 ci->i_truncate_seq,
600 ci->i_truncate_size,
601 false);
602 if (IS_ERR(req)) {
603 ret = PTR_ERR(req);
604 break;
605 }
606
607 num_pages = calc_pages_for(page_align, len);
608 pages = ceph_get_direct_page_vector(data, num_pages, false);
609 if (IS_ERR(pages)) {
610 ret = PTR_ERR(pages);
611 goto out;
612 }
613
614 /*
615 * throw out any page cache pages in this range. this
616 * may block.
617 */
618 truncate_inode_pages_range(inode->i_mapping, pos,
619 (pos+len) | (PAGE_CACHE_SIZE-1));
620 osd_req_op_extent_osd_data_pages(req, 0, pages, len, page_align,
621 false, false);
622
623 /* BUG_ON(vino.snap != CEPH_NOSNAP); */
624 ceph_osdc_build_request(req, pos, snapc, vino.snap, &mtime);
625
626 ret = ceph_osdc_start_request(&fsc->client->osdc, req, false);
627 if (!ret)
628 ret = ceph_osdc_wait_request(&fsc->client->osdc, req);
629
630 ceph_put_page_vector(pages, num_pages, false);
631
632out:
633 ceph_osdc_put_request(req);
634 if (ret == 0) {
635 pos += len;
636 written += len;
637 iov_iter_advance(&i, (size_t)len);
638
639 if (pos > i_size_read(inode)) {
640 check_caps = ceph_inode_set_size(inode, pos);
641 if (check_caps)
642 ceph_check_caps(ceph_inode(inode),
643 CHECK_CAPS_AUTHONLY,
644 NULL);
645 }
646 } else
647 break;
648 }
649
650 if (ret != -EOLDSNAPC && written > 0) {
651 iocb->ki_pos = pos;
652 ret = written;
653 }
654 return ret;
655}
656
657
658/*
659 * Synchronous write, straight from __user pointer or user pages.
660 *
661 * If write spans object boundary, just do multiple writes. (For a
662 * correct atomic write, we should e.g. take write locks on all
663 * objects, rollback on failure, etc.)
664 */
665static ssize_t ceph_sync_write(struct kiocb *iocb, const struct iovec *iov,
666 unsigned long nr_segs, size_t count)
667{
668 struct file *file = iocb->ki_filp;
669 struct inode *inode = file_inode(file);
670 struct ceph_inode_info *ci = ceph_inode(inode);
671 struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
672 struct ceph_snap_context *snapc;
673 struct ceph_vino vino;
674 struct ceph_osd_request *req;
675 struct page **pages;
676 u64 len;
677 int num_pages;
678 int written = 0;
679 int flags;
680 int check_caps = 0;
681 int ret;
682 struct timespec mtime = CURRENT_TIME;
683 loff_t pos = iocb->ki_pos;
684 struct iov_iter i;
685
686 if (ceph_snap(file_inode(file)) != CEPH_NOSNAP)
687 return -EROFS;
688
689 dout("sync_write on file %p %lld~%u\n", file, pos, (unsigned)count);
690
691 ret = filemap_write_and_wait_range(inode->i_mapping, pos, pos + count);
692 if (ret < 0)
693 return ret;
694
695 ret = invalidate_inode_pages2_range(inode->i_mapping,
696 pos >> PAGE_CACHE_SHIFT,
697 (pos + count) >> PAGE_CACHE_SHIFT);
698 if (ret < 0)
699 dout("invalidate_inode_pages2_range returned %d\n", ret);
700
701 flags = CEPH_OSD_FLAG_ORDERSNAP |
702 CEPH_OSD_FLAG_ONDISK |
703 CEPH_OSD_FLAG_WRITE |
704 CEPH_OSD_FLAG_ACK;
705
706 iov_iter_init(&i, iov, nr_segs, count, 0);
707
708 while ((len = iov_iter_count(&i)) > 0) {
709 size_t left;
710 int n;
711
712 snapc = ci->i_snap_realm->cached_context;
713 vino = ceph_vino(inode);
714 req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout,
715 vino, pos, &len, 1,
716 CEPH_OSD_OP_WRITE, flags, snapc,
717 ci->i_truncate_seq,
718 ci->i_truncate_size,
719 false);
720 if (IS_ERR(req)) {
721 ret = PTR_ERR(req);
722 break;
723 }
724
725 /*
726 * write from beginning of first page,
727 * regardless of io alignment
728 */
729 num_pages = (len + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
730
731 pages = ceph_alloc_page_vector(num_pages, GFP_NOFS);
732 if (IS_ERR(pages)) {
733 ret = PTR_ERR(pages);
734 goto out;
735 }
736
737 left = len;
738 for (n = 0; n < num_pages; n++) {
739 size_t plen = min_t(size_t, left, PAGE_SIZE);
740 ret = iov_iter_copy_from_user(pages[n], &i, 0, plen);
741 if (ret != plen) {
742 ret = -EFAULT;
743 break;
744 }
745 left -= ret;
746 iov_iter_advance(&i, ret);
747 }
748
749 if (ret < 0) {
750 ceph_release_page_vector(pages, num_pages);
751 goto out;
752 }
753
754 /* get a second commit callback */
755 req->r_unsafe_callback = ceph_sync_write_unsafe;
756 req->r_inode = inode;
757
758 osd_req_op_extent_osd_data_pages(req, 0, pages, len, 0,
759 false, true);
760
761 /* BUG_ON(vino.snap != CEPH_NOSNAP); */
762 ceph_osdc_build_request(req, pos, snapc, vino.snap, &mtime);
763
764 ret = ceph_osdc_start_request(&fsc->client->osdc, req, false);
765 if (!ret)
766 ret = ceph_osdc_wait_request(&fsc->client->osdc, req);
767
768out:
769 ceph_osdc_put_request(req);
770 if (ret == 0) {
771 pos += len;
772 written += len;
773
774 if (pos > i_size_read(inode)) {
775 check_caps = ceph_inode_set_size(inode, pos);
776 if (check_caps)
777 ceph_check_caps(ceph_inode(inode),
778 CHECK_CAPS_AUTHONLY,
779 NULL);
780 }
781 } else
782 break;
783 }
784
785 if (ret != -EOLDSNAPC && written > 0) {
786 ret = written;
787 iocb->ki_pos = pos;
788 }
789 return ret;
790}
791
792/*
793 * Wrap generic_file_aio_read with checks for cap bits on the inode.
794 * Atomically grab references, so that those bits are not released
795 * back to the MDS mid-read.
796 *
797 * Hmm, the sync read case isn't actually async... should it be?
798 */
799static ssize_t ceph_aio_read(struct kiocb *iocb, const struct iovec *iov,
800 unsigned long nr_segs, loff_t pos)
801{
802 struct file *filp = iocb->ki_filp;
803 struct ceph_file_info *fi = filp->private_data;
804 size_t len = iocb->ki_nbytes;
805 struct inode *inode = file_inode(filp);
806 struct ceph_inode_info *ci = ceph_inode(inode);
807 ssize_t ret;
808 int want, got = 0;
809 int checkeof = 0, read = 0;
810
811again:
812 dout("aio_read %p %llx.%llx %llu~%u trying to get caps on %p\n",
813 inode, ceph_vinop(inode), iocb->ki_pos, (unsigned)len, inode);
814
815 if (fi->fmode & CEPH_FILE_MODE_LAZY)
816 want = CEPH_CAP_FILE_CACHE | CEPH_CAP_FILE_LAZYIO;
817 else
818 want = CEPH_CAP_FILE_CACHE;
819 ret = ceph_get_caps(ci, CEPH_CAP_FILE_RD, want, &got, -1);
820 if (ret < 0)
821 return ret;
822
823 if ((got & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)) == 0 ||
824 (iocb->ki_filp->f_flags & O_DIRECT) ||
825 (fi->flags & CEPH_F_SYNC)) {
826 struct iov_iter i;
827
828 dout("aio_sync_read %p %llx.%llx %llu~%u got cap refs on %s\n",
829 inode, ceph_vinop(inode), iocb->ki_pos, (unsigned)len,
830 ceph_cap_string(got));
831
832 if (!read) {
833 ret = generic_segment_checks(iov, &nr_segs,
834 &len, VERIFY_WRITE);
835 if (ret)
836 goto out;
837 }
838
839 iov_iter_init(&i, iov, nr_segs, len, read);
840
841 /* hmm, this isn't really async... */
842 ret = ceph_sync_read(iocb, &i, &checkeof);
843 } else {
844 /*
845 * We can't modify the content of iov,
846 * so we only read from beginning.
847 */
848 if (read) {
849 iocb->ki_pos = pos;
850 len = iocb->ki_nbytes;
851 read = 0;
852 }
853 dout("aio_read %p %llx.%llx %llu~%u got cap refs on %s\n",
854 inode, ceph_vinop(inode), pos, (unsigned)len,
855 ceph_cap_string(got));
856
857 ret = generic_file_aio_read(iocb, iov, nr_segs, pos);
858 }
859out:
860 dout("aio_read %p %llx.%llx dropping cap refs on %s = %d\n",
861 inode, ceph_vinop(inode), ceph_cap_string(got), (int)ret);
862 ceph_put_cap_refs(ci, got);
863
864 if (checkeof && ret >= 0) {
865 int statret = ceph_do_getattr(inode,
866 CEPH_STAT_CAP_SIZE);
867
868 /* hit EOF or hole? */
869 if (statret == 0 && iocb->ki_pos < inode->i_size &&
870 ret < len) {
871 dout("sync_read hit hole, ppos %lld < size %lld"
872 ", reading more\n", iocb->ki_pos,
873 inode->i_size);
874
875 read += ret;
876 len -= ret;
877 checkeof = 0;
878 goto again;
879 }
880 }
881
882 if (ret >= 0)
883 ret += read;
884
885 return ret;
886}
887
888/*
889 * Take cap references to avoid releasing caps to MDS mid-write.
890 *
891 * If we are synchronous, and write with an old snap context, the OSD
892 * may return EOLDSNAPC. In that case, retry the write.. _after_
893 * dropping our cap refs and allowing the pending snap to logically
894 * complete _before_ this write occurs.
895 *
896 * If we are near ENOSPC, write synchronously.
897 */
898static ssize_t ceph_aio_write(struct kiocb *iocb, const struct iovec *iov,
899 unsigned long nr_segs, loff_t pos)
900{
901 struct file *file = iocb->ki_filp;
902 struct ceph_file_info *fi = file->private_data;
903 struct inode *inode = file_inode(file);
904 struct ceph_inode_info *ci = ceph_inode(inode);
905 struct ceph_osd_client *osdc =
906 &ceph_sb_to_client(inode->i_sb)->client->osdc;
907 ssize_t count, written = 0;
908 int err, want, got;
909
910 if (ceph_snap(inode) != CEPH_NOSNAP)
911 return -EROFS;
912
913 mutex_lock(&inode->i_mutex);
914
915 err = generic_segment_checks(iov, &nr_segs, &count, VERIFY_READ);
916 if (err)
917 goto out;
918
919 /* We can write back this queue in page reclaim */
920 current->backing_dev_info = file->f_mapping->backing_dev_info;
921
922 err = generic_write_checks(file, &pos, &count, S_ISBLK(inode->i_mode));
923 if (err)
924 goto out;
925
926 if (count == 0)
927 goto out;
928
929 err = file_remove_suid(file);
930 if (err)
931 goto out;
932
933 err = file_update_time(file);
934 if (err)
935 goto out;
936
937retry_snap:
938 if (ceph_osdmap_flag(osdc->osdmap, CEPH_OSDMAP_FULL)) {
939 err = -ENOSPC;
940 goto out;
941 }
942
943 dout("aio_write %p %llx.%llx %llu~%zd getting caps. i_size %llu\n",
944 inode, ceph_vinop(inode), pos, count, inode->i_size);
945 if (fi->fmode & CEPH_FILE_MODE_LAZY)
946 want = CEPH_CAP_FILE_BUFFER | CEPH_CAP_FILE_LAZYIO;
947 else
948 want = CEPH_CAP_FILE_BUFFER;
949 got = 0;
950 err = ceph_get_caps(ci, CEPH_CAP_FILE_WR, want, &got, pos + count);
951 if (err < 0)
952 goto out;
953
954 dout("aio_write %p %llx.%llx %llu~%zd got cap refs on %s\n",
955 inode, ceph_vinop(inode), pos, count, ceph_cap_string(got));
956
957 if ((got & (CEPH_CAP_FILE_BUFFER|CEPH_CAP_FILE_LAZYIO)) == 0 ||
958 (file->f_flags & O_DIRECT) || (fi->flags & CEPH_F_SYNC)) {
959 mutex_unlock(&inode->i_mutex);
960 if (file->f_flags & O_DIRECT)
961 written = ceph_sync_direct_write(iocb, iov,
962 nr_segs, count);
963 else
964 written = ceph_sync_write(iocb, iov, nr_segs, count);
965 if (written == -EOLDSNAPC) {
966 dout("aio_write %p %llx.%llx %llu~%u"
967 "got EOLDSNAPC, retrying\n",
968 inode, ceph_vinop(inode),
969 pos, (unsigned)iov->iov_len);
970 mutex_lock(&inode->i_mutex);
971 goto retry_snap;
972 }
973 } else {
974 loff_t old_size = inode->i_size;
975 struct iov_iter from;
976 /*
977 * No need to acquire the i_truncate_mutex. Because
978 * the MDS revokes Fwb caps before sending truncate
979 * message to us. We can't get Fwb cap while there
980 * are pending vmtruncate. So write and vmtruncate
981 * can not run at the same time
982 */
983 iov_iter_init(&from, iov, nr_segs, count, 0);
984 written = generic_perform_write(file, &from, pos);
985 if (likely(written >= 0))
986 iocb->ki_pos = pos + written;
987 if (inode->i_size > old_size)
988 ceph_fscache_update_objectsize(inode);
989 mutex_unlock(&inode->i_mutex);
990 }
991
992 if (written >= 0) {
993 int dirty;
994 spin_lock(&ci->i_ceph_lock);
995 dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_FILE_WR);
996 spin_unlock(&ci->i_ceph_lock);
997 if (dirty)
998 __mark_inode_dirty(inode, dirty);
999 }
1000
1001 dout("aio_write %p %llx.%llx %llu~%u dropping cap refs on %s\n",
1002 inode, ceph_vinop(inode), pos, (unsigned)iov->iov_len,
1003 ceph_cap_string(got));
1004 ceph_put_cap_refs(ci, got);
1005
1006 if (written >= 0 &&
1007 ((file->f_flags & O_SYNC) || IS_SYNC(file->f_mapping->host) ||
1008 ceph_osdmap_flag(osdc->osdmap, CEPH_OSDMAP_NEARFULL))) {
1009 err = vfs_fsync_range(file, pos, pos + written - 1, 1);
1010 if (err < 0)
1011 written = err;
1012 }
1013
1014 goto out_unlocked;
1015
1016out:
1017 mutex_unlock(&inode->i_mutex);
1018out_unlocked:
1019 current->backing_dev_info = NULL;
1020 return written ? written : err;
1021}
1022
1023/*
1024 * llseek. be sure to verify file size on SEEK_END.
1025 */
1026static loff_t ceph_llseek(struct file *file, loff_t offset, int whence)
1027{
1028 struct inode *inode = file->f_mapping->host;
1029 int ret;
1030
1031 mutex_lock(&inode->i_mutex);
1032
1033 if (whence == SEEK_END || whence == SEEK_DATA || whence == SEEK_HOLE) {
1034 ret = ceph_do_getattr(inode, CEPH_STAT_CAP_SIZE);
1035 if (ret < 0) {
1036 offset = ret;
1037 goto out;
1038 }
1039 }
1040
1041 switch (whence) {
1042 case SEEK_END:
1043 offset += inode->i_size;
1044 break;
1045 case SEEK_CUR:
1046 /*
1047 * Here we special-case the lseek(fd, 0, SEEK_CUR)
1048 * position-querying operation. Avoid rewriting the "same"
1049 * f_pos value back to the file because a concurrent read(),
1050 * write() or lseek() might have altered it
1051 */
1052 if (offset == 0) {
1053 offset = file->f_pos;
1054 goto out;
1055 }
1056 offset += file->f_pos;
1057 break;
1058 case SEEK_DATA:
1059 if (offset >= inode->i_size) {
1060 ret = -ENXIO;
1061 goto out;
1062 }
1063 break;
1064 case SEEK_HOLE:
1065 if (offset >= inode->i_size) {
1066 ret = -ENXIO;
1067 goto out;
1068 }
1069 offset = inode->i_size;
1070 break;
1071 }
1072
1073 offset = vfs_setpos(file, offset, inode->i_sb->s_maxbytes);
1074
1075out:
1076 mutex_unlock(&inode->i_mutex);
1077 return offset;
1078}
1079
1080static inline void ceph_zero_partial_page(
1081 struct inode *inode, loff_t offset, unsigned size)
1082{
1083 struct page *page;
1084 pgoff_t index = offset >> PAGE_CACHE_SHIFT;
1085
1086 page = find_lock_page(inode->i_mapping, index);
1087 if (page) {
1088 wait_on_page_writeback(page);
1089 zero_user(page, offset & (PAGE_CACHE_SIZE - 1), size);
1090 unlock_page(page);
1091 page_cache_release(page);
1092 }
1093}
1094
1095static void ceph_zero_pagecache_range(struct inode *inode, loff_t offset,
1096 loff_t length)
1097{
1098 loff_t nearly = round_up(offset, PAGE_CACHE_SIZE);
1099 if (offset < nearly) {
1100 loff_t size = nearly - offset;
1101 if (length < size)
1102 size = length;
1103 ceph_zero_partial_page(inode, offset, size);
1104 offset += size;
1105 length -= size;
1106 }
1107 if (length >= PAGE_CACHE_SIZE) {
1108 loff_t size = round_down(length, PAGE_CACHE_SIZE);
1109 truncate_pagecache_range(inode, offset, offset + size - 1);
1110 offset += size;
1111 length -= size;
1112 }
1113 if (length)
1114 ceph_zero_partial_page(inode, offset, length);
1115}
1116
1117static int ceph_zero_partial_object(struct inode *inode,
1118 loff_t offset, loff_t *length)
1119{
1120 struct ceph_inode_info *ci = ceph_inode(inode);
1121 struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
1122 struct ceph_osd_request *req;
1123 int ret = 0;
1124 loff_t zero = 0;
1125 int op;
1126
1127 if (!length) {
1128 op = offset ? CEPH_OSD_OP_DELETE : CEPH_OSD_OP_TRUNCATE;
1129 length = &zero;
1130 } else {
1131 op = CEPH_OSD_OP_ZERO;
1132 }
1133
1134 req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout,
1135 ceph_vino(inode),
1136 offset, length,
1137 1, op,
1138 CEPH_OSD_FLAG_WRITE |
1139 CEPH_OSD_FLAG_ONDISK,
1140 NULL, 0, 0, false);
1141 if (IS_ERR(req)) {
1142 ret = PTR_ERR(req);
1143 goto out;
1144 }
1145
1146 ceph_osdc_build_request(req, offset, NULL, ceph_vino(inode).snap,
1147 &inode->i_mtime);
1148
1149 ret = ceph_osdc_start_request(&fsc->client->osdc, req, false);
1150 if (!ret) {
1151 ret = ceph_osdc_wait_request(&fsc->client->osdc, req);
1152 if (ret == -ENOENT)
1153 ret = 0;
1154 }
1155 ceph_osdc_put_request(req);
1156
1157out:
1158 return ret;
1159}
1160
1161static int ceph_zero_objects(struct inode *inode, loff_t offset, loff_t length)
1162{
1163 int ret = 0;
1164 struct ceph_inode_info *ci = ceph_inode(inode);
1165 s32 stripe_unit = ceph_file_layout_su(ci->i_layout);
1166 s32 stripe_count = ceph_file_layout_stripe_count(ci->i_layout);
1167 s32 object_size = ceph_file_layout_object_size(ci->i_layout);
1168 u64 object_set_size = object_size * stripe_count;
1169 u64 nearly, t;
1170
1171 /* round offset up to next period boundary */
1172 nearly = offset + object_set_size - 1;
1173 t = nearly;
1174 nearly -= do_div(t, object_set_size);
1175
1176 while (length && offset < nearly) {
1177 loff_t size = length;
1178 ret = ceph_zero_partial_object(inode, offset, &size);
1179 if (ret < 0)
1180 return ret;
1181 offset += size;
1182 length -= size;
1183 }
1184 while (length >= object_set_size) {
1185 int i;
1186 loff_t pos = offset;
1187 for (i = 0; i < stripe_count; ++i) {
1188 ret = ceph_zero_partial_object(inode, pos, NULL);
1189 if (ret < 0)
1190 return ret;
1191 pos += stripe_unit;
1192 }
1193 offset += object_set_size;
1194 length -= object_set_size;
1195 }
1196 while (length) {
1197 loff_t size = length;
1198 ret = ceph_zero_partial_object(inode, offset, &size);
1199 if (ret < 0)
1200 return ret;
1201 offset += size;
1202 length -= size;
1203 }
1204 return ret;
1205}
1206
1207static long ceph_fallocate(struct file *file, int mode,
1208 loff_t offset, loff_t length)
1209{
1210 struct ceph_file_info *fi = file->private_data;
1211 struct inode *inode = file_inode(file);
1212 struct ceph_inode_info *ci = ceph_inode(inode);
1213 struct ceph_osd_client *osdc =
1214 &ceph_inode_to_client(inode)->client->osdc;
1215 int want, got = 0;
1216 int dirty;
1217 int ret = 0;
1218 loff_t endoff = 0;
1219 loff_t size;
1220
1221 if (!S_ISREG(inode->i_mode))
1222 return -EOPNOTSUPP;
1223
1224 mutex_lock(&inode->i_mutex);
1225
1226 if (ceph_snap(inode) != CEPH_NOSNAP) {
1227 ret = -EROFS;
1228 goto unlock;
1229 }
1230
1231 if (ceph_osdmap_flag(osdc->osdmap, CEPH_OSDMAP_FULL) &&
1232 !(mode & FALLOC_FL_PUNCH_HOLE)) {
1233 ret = -ENOSPC;
1234 goto unlock;
1235 }
1236
1237 size = i_size_read(inode);
1238 if (!(mode & FALLOC_FL_KEEP_SIZE))
1239 endoff = offset + length;
1240
1241 if (fi->fmode & CEPH_FILE_MODE_LAZY)
1242 want = CEPH_CAP_FILE_BUFFER | CEPH_CAP_FILE_LAZYIO;
1243 else
1244 want = CEPH_CAP_FILE_BUFFER;
1245
1246 ret = ceph_get_caps(ci, CEPH_CAP_FILE_WR, want, &got, endoff);
1247 if (ret < 0)
1248 goto unlock;
1249
1250 if (mode & FALLOC_FL_PUNCH_HOLE) {
1251 if (offset < size)
1252 ceph_zero_pagecache_range(inode, offset, length);
1253 ret = ceph_zero_objects(inode, offset, length);
1254 } else if (endoff > size) {
1255 truncate_pagecache_range(inode, size, -1);
1256 if (ceph_inode_set_size(inode, endoff))
1257 ceph_check_caps(ceph_inode(inode),
1258 CHECK_CAPS_AUTHONLY, NULL);
1259 }
1260
1261 if (!ret) {
1262 spin_lock(&ci->i_ceph_lock);
1263 dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_FILE_WR);
1264 spin_unlock(&ci->i_ceph_lock);
1265 if (dirty)
1266 __mark_inode_dirty(inode, dirty);
1267 }
1268
1269 ceph_put_cap_refs(ci, got);
1270unlock:
1271 mutex_unlock(&inode->i_mutex);
1272 return ret;
1273}
1274
1275const struct file_operations ceph_file_fops = {
1276 .open = ceph_open,
1277 .release = ceph_release,
1278 .llseek = ceph_llseek,
1279 .read = do_sync_read,
1280 .write = do_sync_write,
1281 .aio_read = ceph_aio_read,
1282 .aio_write = ceph_aio_write,
1283 .mmap = ceph_mmap,
1284 .fsync = ceph_fsync,
1285 .lock = ceph_lock,
1286 .flock = ceph_flock,
1287 .splice_read = generic_file_splice_read,
1288 .splice_write = generic_file_splice_write,
1289 .unlocked_ioctl = ceph_ioctl,
1290 .compat_ioctl = ceph_ioctl,
1291 .fallocate = ceph_fallocate,
1292};
1293