~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

TOMOYO Linux Cross Reference
Linux/fs/ceph/file.c

Version: ~ [ linux-5.16-rc3 ] ~ [ linux-5.15.5 ] ~ [ linux-5.14.21 ] ~ [ linux-5.13.19 ] ~ [ linux-5.12.19 ] ~ [ linux-5.11.22 ] ~ [ linux-5.10.82 ] ~ [ linux-5.9.16 ] ~ [ linux-5.8.18 ] ~ [ linux-5.7.19 ] ~ [ linux-5.6.19 ] ~ [ linux-5.5.19 ] ~ [ linux-5.4.162 ] ~ [ linux-5.3.18 ] ~ [ linux-5.2.21 ] ~ [ linux-5.1.21 ] ~ [ linux-5.0.21 ] ~ [ linux-4.20.17 ] ~ [ linux-4.19.218 ] ~ [ linux-4.18.20 ] ~ [ linux-4.17.19 ] ~ [ linux-4.16.18 ] ~ [ linux-4.15.18 ] ~ [ linux-4.14.256 ] ~ [ linux-4.13.16 ] ~ [ linux-4.12.14 ] ~ [ linux-4.11.12 ] ~ [ linux-4.10.17 ] ~ [ linux-4.9.291 ] ~ [ linux-4.8.17 ] ~ [ linux-4.7.10 ] ~ [ linux-4.6.7 ] ~ [ linux-4.5.7 ] ~ [ linux-4.4.293 ] ~ [ linux-4.3.6 ] ~ [ linux-4.2.8 ] ~ [ linux-4.1.52 ] ~ [ linux-4.0.9 ] ~ [ linux-3.18.140 ] ~ [ linux-3.16.85 ] ~ [ linux-3.14.79 ] ~ [ linux-3.12.74 ] ~ [ linux-3.10.108 ] ~ [ linux-2.6.32.71 ] ~ [ linux-2.6.0 ] ~ [ linux-2.4.37.11 ] ~ [ unix-v6-master ] ~ [ ccs-tools-1.8.5 ] ~ [ policy-sample ] ~
Architecture: ~ [ i386 ] ~ [ alpha ] ~ [ m68k ] ~ [ mips ] ~ [ ppc ] ~ [ sparc ] ~ [ sparc64 ] ~

  1 #include <linux/ceph/ceph_debug.h>
  2 
  3 #include <linux/module.h>
  4 #include <linux/sched.h>
  5 #include <linux/slab.h>
  6 #include <linux/file.h>
  7 #include <linux/mount.h>
  8 #include <linux/namei.h>
  9 #include <linux/writeback.h>
 10 #include <linux/aio.h>
 11 #include <linux/falloc.h>
 12 
 13 #include "super.h"
 14 #include "mds_client.h"
 15 #include "cache.h"
 16 
 17 /*
 18  * Ceph file operations
 19  *
 20  * Implement basic open/close functionality, and implement
 21  * read/write.
 22  *
 23  * We implement three modes of file I/O:
 24  *  - buffered uses the generic_file_aio_{read,write} helpers
 25  *
 26  *  - synchronous is used when there is multi-client read/write
 27  *    sharing, avoids the page cache, and synchronously waits for an
 28  *    ack from the OSD.
 29  *
 30  *  - direct io takes the variant of the sync path that references
 31  *    user pages directly.
 32  *
 33  * fsync() flushes and waits on dirty pages, but just queues metadata
 34  * for writeback: since the MDS can recover size and mtime there is no
 35  * need to wait for MDS acknowledgement.
 36  */
 37 
 38 
 39 /*
 40  * Prepare an open request.  Preallocate ceph_cap to avoid an
 41  * inopportune ENOMEM later.
 42  */
 43 static struct ceph_mds_request *
 44 prepare_open_request(struct super_block *sb, int flags, int create_mode)
 45 {
 46         struct ceph_fs_client *fsc = ceph_sb_to_client(sb);
 47         struct ceph_mds_client *mdsc = fsc->mdsc;
 48         struct ceph_mds_request *req;
 49         int want_auth = USE_ANY_MDS;
 50         int op = (flags & O_CREAT) ? CEPH_MDS_OP_CREATE : CEPH_MDS_OP_OPEN;
 51 
 52         if (flags & (O_WRONLY|O_RDWR|O_CREAT|O_TRUNC))
 53                 want_auth = USE_AUTH_MDS;
 54 
 55         req = ceph_mdsc_create_request(mdsc, op, want_auth);
 56         if (IS_ERR(req))
 57                 goto out;
 58         req->r_fmode = ceph_flags_to_mode(flags);
 59         req->r_args.open.flags = cpu_to_le32(flags);
 60         req->r_args.open.mode = cpu_to_le32(create_mode);
 61 out:
 62         return req;
 63 }
 64 
 65 /*
 66  * initialize private struct file data.
 67  * if we fail, clean up by dropping fmode reference on the ceph_inode
 68  */
 69 static int ceph_init_file(struct inode *inode, struct file *file, int fmode)
 70 {
 71         struct ceph_file_info *cf;
 72         int ret = 0;
 73         struct ceph_inode_info *ci = ceph_inode(inode);
 74         struct ceph_fs_client *fsc = ceph_sb_to_client(inode->i_sb);
 75         struct ceph_mds_client *mdsc = fsc->mdsc;
 76 
 77         switch (inode->i_mode & S_IFMT) {
 78         case S_IFREG:
 79                 /* First file open request creates the cookie, we want to keep
 80                  * this cookie around for the filetime of the inode as not to
 81                  * have to worry about fscache register / revoke / operation
 82                  * races.
 83                  *
 84                  * Also, if we know the operation is going to invalidate data
 85                  * (non readonly) just nuke the cache right away.
 86                  */
 87                 ceph_fscache_register_inode_cookie(mdsc->fsc, ci);
 88                 if ((fmode & CEPH_FILE_MODE_WR))
 89                         ceph_fscache_invalidate(inode);
 90         case S_IFDIR:
 91                 dout("init_file %p %p 0%o (regular)\n", inode, file,
 92                      inode->i_mode);
 93                 cf = kmem_cache_alloc(ceph_file_cachep, GFP_NOFS | __GFP_ZERO);
 94                 if (cf == NULL) {
 95                         ceph_put_fmode(ceph_inode(inode), fmode); /* clean up */
 96                         return -ENOMEM;
 97                 }
 98                 cf->fmode = fmode;
 99                 cf->next_offset = 2;
100                 file->private_data = cf;
101                 BUG_ON(inode->i_fop->release != ceph_release);
102                 break;
103 
104         case S_IFLNK:
105                 dout("init_file %p %p 0%o (symlink)\n", inode, file,
106                      inode->i_mode);
107                 ceph_put_fmode(ceph_inode(inode), fmode); /* clean up */
108                 break;
109 
110         default:
111                 dout("init_file %p %p 0%o (special)\n", inode, file,
112                      inode->i_mode);
113                 /*
114                  * we need to drop the open ref now, since we don't
115                  * have .release set to ceph_release.
116                  */
117                 ceph_put_fmode(ceph_inode(inode), fmode); /* clean up */
118                 BUG_ON(inode->i_fop->release == ceph_release);
119 
120                 /* call the proper open fop */
121                 ret = inode->i_fop->open(inode, file);
122         }
123         return ret;
124 }
125 
126 /*
127  * If we already have the requisite capabilities, we can satisfy
128  * the open request locally (no need to request new caps from the
129  * MDS).  We do, however, need to inform the MDS (asynchronously)
130  * if our wanted caps set expands.
131  */
132 int ceph_open(struct inode *inode, struct file *file)
133 {
134         struct ceph_inode_info *ci = ceph_inode(inode);
135         struct ceph_fs_client *fsc = ceph_sb_to_client(inode->i_sb);
136         struct ceph_mds_client *mdsc = fsc->mdsc;
137         struct ceph_mds_request *req;
138         struct ceph_file_info *cf = file->private_data;
139         struct inode *parent_inode = NULL;
140         int err;
141         int flags, fmode, wanted;
142 
143         if (cf) {
144                 dout("open file %p is already opened\n", file);
145                 return 0;
146         }
147 
148         /* filter out O_CREAT|O_EXCL; vfs did that already.  yuck. */
149         flags = file->f_flags & ~(O_CREAT|O_EXCL);
150         if (S_ISDIR(inode->i_mode))
151                 flags = O_DIRECTORY;  /* mds likes to know */
152 
153         dout("open inode %p ino %llx.%llx file %p flags %d (%d)\n", inode,
154              ceph_vinop(inode), file, flags, file->f_flags);
155         fmode = ceph_flags_to_mode(flags);
156         wanted = ceph_caps_for_mode(fmode);
157 
158         /* snapped files are read-only */
159         if (ceph_snap(inode) != CEPH_NOSNAP && (file->f_mode & FMODE_WRITE))
160                 return -EROFS;
161 
162         /* trivially open snapdir */
163         if (ceph_snap(inode) == CEPH_SNAPDIR) {
164                 spin_lock(&ci->i_ceph_lock);
165                 __ceph_get_fmode(ci, fmode);
166                 spin_unlock(&ci->i_ceph_lock);
167                 return ceph_init_file(inode, file, fmode);
168         }
169 
170         /*
171          * No need to block if we have caps on the auth MDS (for
172          * write) or any MDS (for read).  Update wanted set
173          * asynchronously.
174          */
175         spin_lock(&ci->i_ceph_lock);
176         if (__ceph_is_any_real_caps(ci) &&
177             (((fmode & CEPH_FILE_MODE_WR) == 0) || ci->i_auth_cap)) {
178                 int mds_wanted = __ceph_caps_mds_wanted(ci);
179                 int issued = __ceph_caps_issued(ci, NULL);
180 
181                 dout("open %p fmode %d want %s issued %s using existing\n",
182                      inode, fmode, ceph_cap_string(wanted),
183                      ceph_cap_string(issued));
184                 __ceph_get_fmode(ci, fmode);
185                 spin_unlock(&ci->i_ceph_lock);
186 
187                 /* adjust wanted? */
188                 if ((issued & wanted) != wanted &&
189                     (mds_wanted & wanted) != wanted &&
190                     ceph_snap(inode) != CEPH_SNAPDIR)
191                         ceph_check_caps(ci, 0, NULL);
192 
193                 return ceph_init_file(inode, file, fmode);
194         } else if (ceph_snap(inode) != CEPH_NOSNAP &&
195                    (ci->i_snap_caps & wanted) == wanted) {
196                 __ceph_get_fmode(ci, fmode);
197                 spin_unlock(&ci->i_ceph_lock);
198                 return ceph_init_file(inode, file, fmode);
199         }
200 
201         spin_unlock(&ci->i_ceph_lock);
202 
203         dout("open fmode %d wants %s\n", fmode, ceph_cap_string(wanted));
204         req = prepare_open_request(inode->i_sb, flags, 0);
205         if (IS_ERR(req)) {
206                 err = PTR_ERR(req);
207                 goto out;
208         }
209         req->r_inode = inode;
210         ihold(inode);
211 
212         req->r_num_caps = 1;
213         if (flags & O_CREAT)
214                 parent_inode = ceph_get_dentry_parent_inode(file->f_path.dentry);
215         err = ceph_mdsc_do_request(mdsc, parent_inode, req);
216         iput(parent_inode);
217         if (!err)
218                 err = ceph_init_file(inode, file, req->r_fmode);
219         ceph_mdsc_put_request(req);
220         dout("open result=%d on %llx.%llx\n", err, ceph_vinop(inode));
221 out:
222         return err;
223 }
224 
225 
226 /*
227  * Do a lookup + open with a single request.  If we get a non-existent
228  * file or symlink, return 1 so the VFS can retry.
229  */
230 int ceph_atomic_open(struct inode *dir, struct dentry *dentry,
231                      struct file *file, unsigned flags, umode_t mode,
232                      int *opened)
233 {
234         struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
235         struct ceph_mds_client *mdsc = fsc->mdsc;
236         struct ceph_mds_request *req;
237         struct dentry *dn;
238         struct ceph_acls_info acls = {};
239         int err;
240 
241         dout("atomic_open %p dentry %p '%pd' %s flags %d mode 0%o\n",
242              dir, dentry, dentry,
243              d_unhashed(dentry) ? "unhashed" : "hashed", flags, mode);
244 
245         if (dentry->d_name.len > NAME_MAX)
246                 return -ENAMETOOLONG;
247 
248         err = ceph_init_dentry(dentry);
249         if (err < 0)
250                 return err;
251 
252         if (flags & O_CREAT) {
253                 err = ceph_pre_init_acls(dir, &mode, &acls);
254                 if (err < 0)
255                         return err;
256         }
257 
258         /* do the open */
259         req = prepare_open_request(dir->i_sb, flags, mode);
260         if (IS_ERR(req)) {
261                 err = PTR_ERR(req);
262                 goto out_acl;
263         }
264         req->r_dentry = dget(dentry);
265         req->r_num_caps = 2;
266         if (flags & O_CREAT) {
267                 req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
268                 req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
269                 if (acls.pagelist) {
270                         req->r_pagelist = acls.pagelist;
271                         acls.pagelist = NULL;
272                 }
273         }
274         req->r_locked_dir = dir;           /* caller holds dir->i_mutex */
275         err = ceph_mdsc_do_request(mdsc,
276                                    (flags & (O_CREAT|O_TRUNC)) ? dir : NULL,
277                                    req);
278         err = ceph_handle_snapdir(req, dentry, err);
279         if (err)
280                 goto out_req;
281 
282         if (err == 0 && (flags & O_CREAT) && !req->r_reply_info.head->is_dentry)
283                 err = ceph_handle_notrace_create(dir, dentry);
284 
285         if (d_unhashed(dentry)) {
286                 dn = ceph_finish_lookup(req, dentry, err);
287                 if (IS_ERR(dn))
288                         err = PTR_ERR(dn);
289         } else {
290                 /* we were given a hashed negative dentry */
291                 dn = NULL;
292         }
293         if (err)
294                 goto out_req;
295         if (dn || dentry->d_inode == NULL || d_is_symlink(dentry)) {
296                 /* make vfs retry on splice, ENOENT, or symlink */
297                 dout("atomic_open finish_no_open on dn %p\n", dn);
298                 err = finish_no_open(file, dn);
299         } else {
300                 dout("atomic_open finish_open on dn %p\n", dn);
301                 if (req->r_op == CEPH_MDS_OP_CREATE && req->r_reply_info.has_create_ino) {
302                         ceph_init_inode_acls(dentry->d_inode, &acls);
303                         *opened |= FILE_CREATED;
304                 }
305                 err = finish_open(file, dentry, ceph_open, opened);
306         }
307 out_req:
308         if (!req->r_err && req->r_target_inode)
309                 ceph_put_fmode(ceph_inode(req->r_target_inode), req->r_fmode);
310         ceph_mdsc_put_request(req);
311 out_acl:
312         ceph_release_acls_info(&acls);
313         dout("atomic_open result=%d\n", err);
314         return err;
315 }
316 
317 int ceph_release(struct inode *inode, struct file *file)
318 {
319         struct ceph_inode_info *ci = ceph_inode(inode);
320         struct ceph_file_info *cf = file->private_data;
321 
322         dout("release inode %p file %p\n", inode, file);
323         ceph_put_fmode(ci, cf->fmode);
324         if (cf->last_readdir)
325                 ceph_mdsc_put_request(cf->last_readdir);
326         kfree(cf->last_name);
327         kfree(cf->dir_info);
328         dput(cf->dentry);
329         kmem_cache_free(ceph_file_cachep, cf);
330 
331         /* wake up anyone waiting for caps on this inode */
332         wake_up_all(&ci->i_cap_wq);
333         return 0;
334 }
335 
336 enum {
337         CHECK_EOF = 1,
338         READ_INLINE = 2,
339 };
340 
341 /*
342  * Read a range of bytes striped over one or more objects.  Iterate over
343  * objects we stripe over.  (That's not atomic, but good enough for now.)
344  *
345  * If we get a short result from the OSD, check against i_size; we need to
346  * only return a short read to the caller if we hit EOF.
347  */
348 static int striped_read(struct inode *inode,
349                         u64 off, u64 len,
350                         struct page **pages, int num_pages,
351                         int *checkeof, bool o_direct,
352                         unsigned long buf_align)
353 {
354         struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
355         struct ceph_inode_info *ci = ceph_inode(inode);
356         u64 pos, this_len, left;
357         int io_align, page_align;
358         int pages_left;
359         int read;
360         struct page **page_pos;
361         int ret;
362         bool hit_stripe, was_short;
363 
364         /*
365          * we may need to do multiple reads.  not atomic, unfortunately.
366          */
367         pos = off;
368         left = len;
369         page_pos = pages;
370         pages_left = num_pages;
371         read = 0;
372         io_align = off & ~PAGE_MASK;
373 
374 more:
375         if (o_direct)
376                 page_align = (pos - io_align + buf_align) & ~PAGE_MASK;
377         else
378                 page_align = pos & ~PAGE_MASK;
379         this_len = left;
380         ret = ceph_osdc_readpages(&fsc->client->osdc, ceph_vino(inode),
381                                   &ci->i_layout, pos, &this_len,
382                                   ci->i_truncate_seq,
383                                   ci->i_truncate_size,
384                                   page_pos, pages_left, page_align);
385         if (ret == -ENOENT)
386                 ret = 0;
387         hit_stripe = this_len < left;
388         was_short = ret >= 0 && ret < this_len;
389         dout("striped_read %llu~%llu (read %u) got %d%s%s\n", pos, left, read,
390              ret, hit_stripe ? " HITSTRIPE" : "", was_short ? " SHORT" : "");
391 
392         if (ret >= 0) {
393                 int didpages;
394                 if (was_short && (pos + ret < inode->i_size)) {
395                         int zlen = min(this_len - ret,
396                                        inode->i_size - pos - ret);
397                         int zoff = (o_direct ? buf_align : io_align) +
398                                     read + ret;
399                         dout(" zero gap %llu to %llu\n",
400                                 pos + ret, pos + ret + zlen);
401                         ceph_zero_page_vector_range(zoff, zlen, pages);
402                         ret += zlen;
403                 }
404 
405                 didpages = (page_align + ret) >> PAGE_CACHE_SHIFT;
406                 pos += ret;
407                 read = pos - off;
408                 left -= ret;
409                 page_pos += didpages;
410                 pages_left -= didpages;
411 
412                 /* hit stripe and need continue*/
413                 if (left && hit_stripe && pos < inode->i_size)
414                         goto more;
415         }
416 
417         if (read > 0) {
418                 ret = read;
419                 /* did we bounce off eof? */
420                 if (pos + left > inode->i_size)
421                         *checkeof = CHECK_EOF;
422         }
423 
424         dout("striped_read returns %d\n", ret);
425         return ret;
426 }
427 
428 /*
429  * Completely synchronous read and write methods.  Direct from __user
430  * buffer to osd, or directly to user pages (if O_DIRECT).
431  *
432  * If the read spans object boundary, just do multiple reads.
433  */
434 static ssize_t ceph_sync_read(struct kiocb *iocb, struct iov_iter *i,
435                                 int *checkeof)
436 {
437         struct file *file = iocb->ki_filp;
438         struct inode *inode = file_inode(file);
439         struct page **pages;
440         u64 off = iocb->ki_pos;
441         int num_pages, ret;
442         size_t len = iov_iter_count(i);
443 
444         dout("sync_read on file %p %llu~%u %s\n", file, off,
445              (unsigned)len,
446              (file->f_flags & O_DIRECT) ? "O_DIRECT" : "");
447 
448         if (!len)
449                 return 0;
450         /*
451          * flush any page cache pages in this range.  this
452          * will make concurrent normal and sync io slow,
453          * but it will at least behave sensibly when they are
454          * in sequence.
455          */
456         ret = filemap_write_and_wait_range(inode->i_mapping, off,
457                                                 off + len);
458         if (ret < 0)
459                 return ret;
460 
461         if (file->f_flags & O_DIRECT) {
462                 while (iov_iter_count(i)) {
463                         size_t start;
464                         ssize_t n;
465 
466                         n = iov_iter_get_pages_alloc(i, &pages, INT_MAX, &start);
467                         if (n < 0)
468                                 return n;
469 
470                         num_pages = (n + start + PAGE_SIZE - 1) / PAGE_SIZE;
471 
472                         ret = striped_read(inode, off, n,
473                                            pages, num_pages, checkeof,
474                                            1, start);
475 
476                         ceph_put_page_vector(pages, num_pages, true);
477 
478                         if (ret <= 0)
479                                 break;
480                         off += ret;
481                         iov_iter_advance(i, ret);
482                         if (ret < n)
483                                 break;
484                 }
485         } else {
486                 num_pages = calc_pages_for(off, len);
487                 pages = ceph_alloc_page_vector(num_pages, GFP_NOFS);
488                 if (IS_ERR(pages))
489                         return PTR_ERR(pages);
490                 ret = striped_read(inode, off, len, pages,
491                                         num_pages, checkeof, 0, 0);
492                 if (ret > 0) {
493                         int l, k = 0;
494                         size_t left = ret;
495 
496                         while (left) {
497                                 size_t page_off = off & ~PAGE_MASK;
498                                 size_t copy = min_t(size_t,
499                                                     PAGE_SIZE - page_off, left);
500                                 l = copy_page_to_iter(pages[k++], page_off,
501                                                       copy, i);
502                                 off += l;
503                                 left -= l;
504                                 if (l < copy)
505                                         break;
506                         }
507                 }
508                 ceph_release_page_vector(pages, num_pages);
509         }
510 
511         if (off > iocb->ki_pos) {
512                 ret = off - iocb->ki_pos;
513                 iocb->ki_pos = off;
514         }
515 
516         dout("sync_read result %d\n", ret);
517         return ret;
518 }
519 
520 /*
521  * Write commit request unsafe callback, called to tell us when a
522  * request is unsafe (that is, in flight--has been handed to the
523  * messenger to send to its target osd).  It is called again when
524  * we've received a response message indicating the request is
525  * "safe" (its CEPH_OSD_FLAG_ONDISK flag is set), or when a request
526  * is completed early (and unsuccessfully) due to a timeout or
527  * interrupt.
528  *
529  * This is used if we requested both an ACK and ONDISK commit reply
530  * from the OSD.
531  */
532 static void ceph_sync_write_unsafe(struct ceph_osd_request *req, bool unsafe)
533 {
534         struct ceph_inode_info *ci = ceph_inode(req->r_inode);
535 
536         dout("%s %p tid %llu %ssafe\n", __func__, req, req->r_tid,
537                 unsafe ? "un" : "");
538         if (unsafe) {
539                 ceph_get_cap_refs(ci, CEPH_CAP_FILE_WR);
540                 spin_lock(&ci->i_unsafe_lock);
541                 list_add_tail(&req->r_unsafe_item,
542                               &ci->i_unsafe_writes);
543                 spin_unlock(&ci->i_unsafe_lock);
544         } else {
545                 spin_lock(&ci->i_unsafe_lock);
546                 list_del_init(&req->r_unsafe_item);
547                 spin_unlock(&ci->i_unsafe_lock);
548                 ceph_put_cap_refs(ci, CEPH_CAP_FILE_WR);
549         }
550 }
551 
552 
553 /*
554  * Synchronous write, straight from __user pointer or user pages.
555  *
556  * If write spans object boundary, just do multiple writes.  (For a
557  * correct atomic write, we should e.g. take write locks on all
558  * objects, rollback on failure, etc.)
559  */
560 static ssize_t
561 ceph_sync_direct_write(struct kiocb *iocb, struct iov_iter *from, loff_t pos)
562 {
563         struct file *file = iocb->ki_filp;
564         struct inode *inode = file_inode(file);
565         struct ceph_inode_info *ci = ceph_inode(inode);
566         struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
567         struct ceph_snap_context *snapc;
568         struct ceph_vino vino;
569         struct ceph_osd_request *req;
570         struct page **pages;
571         int num_pages;
572         int written = 0;
573         int flags;
574         int check_caps = 0;
575         int ret;
576         struct timespec mtime = CURRENT_TIME;
577         size_t count = iov_iter_count(from);
578 
579         if (ceph_snap(file_inode(file)) != CEPH_NOSNAP)
580                 return -EROFS;
581 
582         dout("sync_direct_write on file %p %lld~%u\n", file, pos,
583              (unsigned)count);
584 
585         ret = filemap_write_and_wait_range(inode->i_mapping, pos, pos + count);
586         if (ret < 0)
587                 return ret;
588 
589         ret = invalidate_inode_pages2_range(inode->i_mapping,
590                                             pos >> PAGE_CACHE_SHIFT,
591                                             (pos + count) >> PAGE_CACHE_SHIFT);
592         if (ret < 0)
593                 dout("invalidate_inode_pages2_range returned %d\n", ret);
594 
595         flags = CEPH_OSD_FLAG_ORDERSNAP |
596                 CEPH_OSD_FLAG_ONDISK |
597                 CEPH_OSD_FLAG_WRITE;
598 
599         while (iov_iter_count(from) > 0) {
600                 u64 len = iov_iter_single_seg_count(from);
601                 size_t start;
602                 ssize_t n;
603 
604                 snapc = ci->i_snap_realm->cached_context;
605                 vino = ceph_vino(inode);
606                 req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout,
607                                             vino, pos, &len, 0,
608                                             2,/*include a 'startsync' command*/
609                                             CEPH_OSD_OP_WRITE, flags, snapc,
610                                             ci->i_truncate_seq,
611                                             ci->i_truncate_size,
612                                             false);
613                 if (IS_ERR(req)) {
614                         ret = PTR_ERR(req);
615                         break;
616                 }
617 
618                 osd_req_op_init(req, 1, CEPH_OSD_OP_STARTSYNC);
619 
620                 n = iov_iter_get_pages_alloc(from, &pages, len, &start);
621                 if (unlikely(n < 0)) {
622                         ret = n;
623                         ceph_osdc_put_request(req);
624                         break;
625                 }
626 
627                 num_pages = (n + start + PAGE_SIZE - 1) / PAGE_SIZE;
628                 /*
629                  * throw out any page cache pages in this range. this
630                  * may block.
631                  */
632                 truncate_inode_pages_range(inode->i_mapping, pos,
633                                    (pos+n) | (PAGE_CACHE_SIZE-1));
634                 osd_req_op_extent_osd_data_pages(req, 0, pages, n, start,
635                                                 false, false);
636 
637                 /* BUG_ON(vino.snap != CEPH_NOSNAP); */
638                 ceph_osdc_build_request(req, pos, snapc, vino.snap, &mtime);
639 
640                 ret = ceph_osdc_start_request(&fsc->client->osdc, req, false);
641                 if (!ret)
642                         ret = ceph_osdc_wait_request(&fsc->client->osdc, req);
643 
644                 ceph_put_page_vector(pages, num_pages, false);
645 
646                 ceph_osdc_put_request(req);
647                 if (ret)
648                         break;
649                 pos += n;
650                 written += n;
651                 iov_iter_advance(from, n);
652 
653                 if (pos > i_size_read(inode)) {
654                         check_caps = ceph_inode_set_size(inode, pos);
655                         if (check_caps)
656                                 ceph_check_caps(ceph_inode(inode),
657                                                 CHECK_CAPS_AUTHONLY,
658                                                 NULL);
659                 }
660         }
661 
662         if (ret != -EOLDSNAPC && written > 0) {
663                 iocb->ki_pos = pos;
664                 ret = written;
665         }
666         return ret;
667 }
668 
669 
670 /*
671  * Synchronous write, straight from __user pointer or user pages.
672  *
673  * If write spans object boundary, just do multiple writes.  (For a
674  * correct atomic write, we should e.g. take write locks on all
675  * objects, rollback on failure, etc.)
676  */
677 static ssize_t
678 ceph_sync_write(struct kiocb *iocb, struct iov_iter *from, loff_t pos)
679 {
680         struct file *file = iocb->ki_filp;
681         struct inode *inode = file_inode(file);
682         struct ceph_inode_info *ci = ceph_inode(inode);
683         struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
684         struct ceph_snap_context *snapc;
685         struct ceph_vino vino;
686         struct ceph_osd_request *req;
687         struct page **pages;
688         u64 len;
689         int num_pages;
690         int written = 0;
691         int flags;
692         int check_caps = 0;
693         int ret;
694         struct timespec mtime = CURRENT_TIME;
695         size_t count = iov_iter_count(from);
696 
697         if (ceph_snap(file_inode(file)) != CEPH_NOSNAP)
698                 return -EROFS;
699 
700         dout("sync_write on file %p %lld~%u\n", file, pos, (unsigned)count);
701 
702         ret = filemap_write_and_wait_range(inode->i_mapping, pos, pos + count);
703         if (ret < 0)
704                 return ret;
705 
706         ret = invalidate_inode_pages2_range(inode->i_mapping,
707                                             pos >> PAGE_CACHE_SHIFT,
708                                             (pos + count) >> PAGE_CACHE_SHIFT);
709         if (ret < 0)
710                 dout("invalidate_inode_pages2_range returned %d\n", ret);
711 
712         flags = CEPH_OSD_FLAG_ORDERSNAP |
713                 CEPH_OSD_FLAG_ONDISK |
714                 CEPH_OSD_FLAG_WRITE |
715                 CEPH_OSD_FLAG_ACK;
716 
717         while ((len = iov_iter_count(from)) > 0) {
718                 size_t left;
719                 int n;
720 
721                 snapc = ci->i_snap_realm->cached_context;
722                 vino = ceph_vino(inode);
723                 req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout,
724                                             vino, pos, &len, 0, 1,
725                                             CEPH_OSD_OP_WRITE, flags, snapc,
726                                             ci->i_truncate_seq,
727                                             ci->i_truncate_size,
728                                             false);
729                 if (IS_ERR(req)) {
730                         ret = PTR_ERR(req);
731                         break;
732                 }
733 
734                 /*
735                  * write from beginning of first page,
736                  * regardless of io alignment
737                  */
738                 num_pages = (len + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
739 
740                 pages = ceph_alloc_page_vector(num_pages, GFP_NOFS);
741                 if (IS_ERR(pages)) {
742                         ret = PTR_ERR(pages);
743                         goto out;
744                 }
745 
746                 left = len;
747                 for (n = 0; n < num_pages; n++) {
748                         size_t plen = min_t(size_t, left, PAGE_SIZE);
749                         ret = copy_page_from_iter(pages[n], 0, plen, from);
750                         if (ret != plen) {
751                                 ret = -EFAULT;
752                                 break;
753                         }
754                         left -= ret;
755                 }
756 
757                 if (ret < 0) {
758                         ceph_release_page_vector(pages, num_pages);
759                         goto out;
760                 }
761 
762                 /* get a second commit callback */
763                 req->r_unsafe_callback = ceph_sync_write_unsafe;
764                 req->r_inode = inode;
765 
766                 osd_req_op_extent_osd_data_pages(req, 0, pages, len, 0,
767                                                 false, true);
768 
769                 /* BUG_ON(vino.snap != CEPH_NOSNAP); */
770                 ceph_osdc_build_request(req, pos, snapc, vino.snap, &mtime);
771 
772                 ret = ceph_osdc_start_request(&fsc->client->osdc, req, false);
773                 if (!ret)
774                         ret = ceph_osdc_wait_request(&fsc->client->osdc, req);
775 
776 out:
777                 ceph_osdc_put_request(req);
778                 if (ret == 0) {
779                         pos += len;
780                         written += len;
781 
782                         if (pos > i_size_read(inode)) {
783                                 check_caps = ceph_inode_set_size(inode, pos);
784                                 if (check_caps)
785                                         ceph_check_caps(ceph_inode(inode),
786                                                         CHECK_CAPS_AUTHONLY,
787                                                         NULL);
788                         }
789                 } else
790                         break;
791         }
792 
793         if (ret != -EOLDSNAPC && written > 0) {
794                 ret = written;
795                 iocb->ki_pos = pos;
796         }
797         return ret;
798 }
799 
800 /*
801  * Wrap generic_file_aio_read with checks for cap bits on the inode.
802  * Atomically grab references, so that those bits are not released
803  * back to the MDS mid-read.
804  *
805  * Hmm, the sync read case isn't actually async... should it be?
806  */
807 static ssize_t ceph_read_iter(struct kiocb *iocb, struct iov_iter *to)
808 {
809         struct file *filp = iocb->ki_filp;
810         struct ceph_file_info *fi = filp->private_data;
811         size_t len = iocb->ki_nbytes;
812         struct inode *inode = file_inode(filp);
813         struct ceph_inode_info *ci = ceph_inode(inode);
814         struct page *pinned_page = NULL;
815         ssize_t ret;
816         int want, got = 0;
817         int retry_op = 0, read = 0;
818 
819 again:
820         dout("aio_read %p %llx.%llx %llu~%u trying to get caps on %p\n",
821              inode, ceph_vinop(inode), iocb->ki_pos, (unsigned)len, inode);
822 
823         if (fi->fmode & CEPH_FILE_MODE_LAZY)
824                 want = CEPH_CAP_FILE_CACHE | CEPH_CAP_FILE_LAZYIO;
825         else
826                 want = CEPH_CAP_FILE_CACHE;
827         ret = ceph_get_caps(ci, CEPH_CAP_FILE_RD, want, -1, &got, &pinned_page);
828         if (ret < 0)
829                 return ret;
830 
831         if ((got & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)) == 0 ||
832             (iocb->ki_filp->f_flags & O_DIRECT) ||
833             (fi->flags & CEPH_F_SYNC)) {
834 
835                 dout("aio_sync_read %p %llx.%llx %llu~%u got cap refs on %s\n",
836                      inode, ceph_vinop(inode), iocb->ki_pos, (unsigned)len,
837                      ceph_cap_string(got));
838 
839                 if (ci->i_inline_version == CEPH_INLINE_NONE) {
840                         /* hmm, this isn't really async... */
841                         ret = ceph_sync_read(iocb, to, &retry_op);
842                 } else {
843                         retry_op = READ_INLINE;
844                 }
845         } else {
846                 dout("aio_read %p %llx.%llx %llu~%u got cap refs on %s\n",
847                      inode, ceph_vinop(inode), iocb->ki_pos, (unsigned)len,
848                      ceph_cap_string(got));
849 
850                 ret = generic_file_read_iter(iocb, to);
851         }
852         dout("aio_read %p %llx.%llx dropping cap refs on %s = %d\n",
853              inode, ceph_vinop(inode), ceph_cap_string(got), (int)ret);
854         if (pinned_page) {
855                 page_cache_release(pinned_page);
856                 pinned_page = NULL;
857         }
858         ceph_put_cap_refs(ci, got);
859         if (retry_op && ret >= 0) {
860                 int statret;
861                 struct page *page = NULL;
862                 loff_t i_size;
863                 if (retry_op == READ_INLINE) {
864                         page = __page_cache_alloc(GFP_NOFS);
865                         if (!page)
866                                 return -ENOMEM;
867                 }
868 
869                 statret = __ceph_do_getattr(inode, page,
870                                             CEPH_STAT_CAP_INLINE_DATA, !!page);
871                 if (statret < 0) {
872                          __free_page(page);
873                         if (statret == -ENODATA) {
874                                 BUG_ON(retry_op != READ_INLINE);
875                                 goto again;
876                         }
877                         return statret;
878                 }
879 
880                 i_size = i_size_read(inode);
881                 if (retry_op == READ_INLINE) {
882                         BUG_ON(ret > 0 || read > 0);
883                         if (iocb->ki_pos < i_size &&
884                             iocb->ki_pos < PAGE_CACHE_SIZE) {
885                                 loff_t end = min_t(loff_t, i_size,
886                                                    iocb->ki_pos + len);
887                                 end = min_t(loff_t, end, PAGE_CACHE_SIZE);
888                                 if (statret < end)
889                                         zero_user_segment(page, statret, end);
890                                 ret = copy_page_to_iter(page,
891                                                 iocb->ki_pos & ~PAGE_MASK,
892                                                 end - iocb->ki_pos, to);
893                                 iocb->ki_pos += ret;
894                                 read += ret;
895                         }
896                         if (iocb->ki_pos < i_size && read < len) {
897                                 size_t zlen = min_t(size_t, len - read,
898                                                     i_size - iocb->ki_pos);
899                                 ret = iov_iter_zero(zlen, to);
900                                 iocb->ki_pos += ret;
901                                 read += ret;
902                         }
903                         __free_pages(page, 0);
904                         return read;
905                 }
906 
907                 /* hit EOF or hole? */
908                 if (retry_op == CHECK_EOF && iocb->ki_pos < i_size &&
909                     ret < len) {
910                         dout("sync_read hit hole, ppos %lld < size %lld"
911                              ", reading more\n", iocb->ki_pos,
912                              inode->i_size);
913 
914                         read += ret;
915                         len -= ret;
916                         retry_op = 0;
917                         goto again;
918                 }
919         }
920 
921         if (ret >= 0)
922                 ret += read;
923 
924         return ret;
925 }
926 
927 /*
928  * Take cap references to avoid releasing caps to MDS mid-write.
929  *
930  * If we are synchronous, and write with an old snap context, the OSD
931  * may return EOLDSNAPC.  In that case, retry the write.. _after_
932  * dropping our cap refs and allowing the pending snap to logically
933  * complete _before_ this write occurs.
934  *
935  * If we are near ENOSPC, write synchronously.
936  */
937 static ssize_t ceph_write_iter(struct kiocb *iocb, struct iov_iter *from)
938 {
939         struct file *file = iocb->ki_filp;
940         struct ceph_file_info *fi = file->private_data;
941         struct inode *inode = file_inode(file);
942         struct ceph_inode_info *ci = ceph_inode(inode);
943         struct ceph_osd_client *osdc =
944                 &ceph_sb_to_client(inode->i_sb)->client->osdc;
945         ssize_t count = iov_iter_count(from), written = 0;
946         int err, want, got;
947         loff_t pos = iocb->ki_pos;
948 
949         if (ceph_snap(inode) != CEPH_NOSNAP)
950                 return -EROFS;
951 
952         mutex_lock(&inode->i_mutex);
953 
954         /* We can write back this queue in page reclaim */
955         current->backing_dev_info = inode_to_bdi(inode);
956 
957         err = generic_write_checks(file, &pos, &count, S_ISBLK(inode->i_mode));
958         if (err)
959                 goto out;
960 
961         if (count == 0)
962                 goto out;
963         iov_iter_truncate(from, count);
964 
965         err = file_remove_suid(file);
966         if (err)
967                 goto out;
968 
969         err = file_update_time(file);
970         if (err)
971                 goto out;
972 
973         if (ci->i_inline_version != CEPH_INLINE_NONE) {
974                 err = ceph_uninline_data(file, NULL);
975                 if (err < 0)
976                         goto out;
977         }
978 
979 retry_snap:
980         if (ceph_osdmap_flag(osdc->osdmap, CEPH_OSDMAP_FULL)) {
981                 err = -ENOSPC;
982                 goto out;
983         }
984 
985         dout("aio_write %p %llx.%llx %llu~%zd getting caps. i_size %llu\n",
986              inode, ceph_vinop(inode), pos, count, inode->i_size);
987         if (fi->fmode & CEPH_FILE_MODE_LAZY)
988                 want = CEPH_CAP_FILE_BUFFER | CEPH_CAP_FILE_LAZYIO;
989         else
990                 want = CEPH_CAP_FILE_BUFFER;
991         got = 0;
992         err = ceph_get_caps(ci, CEPH_CAP_FILE_WR, want, pos + count,
993                             &got, NULL);
994         if (err < 0)
995                 goto out;
996 
997         dout("aio_write %p %llx.%llx %llu~%zd got cap refs on %s\n",
998              inode, ceph_vinop(inode), pos, count, ceph_cap_string(got));
999 
1000         if ((got & (CEPH_CAP_FILE_BUFFER|CEPH_CAP_FILE_LAZYIO)) == 0 ||
1001             (file->f_flags & O_DIRECT) || (fi->flags & CEPH_F_SYNC)) {
1002                 struct iov_iter data;
1003                 mutex_unlock(&inode->i_mutex);
1004                 /* we might need to revert back to that point */
1005                 data = *from;
1006                 if (file->f_flags & O_DIRECT)
1007                         written = ceph_sync_direct_write(iocb, &data, pos);
1008                 else
1009                         written = ceph_sync_write(iocb, &data, pos);
1010                 if (written == -EOLDSNAPC) {
1011                         dout("aio_write %p %llx.%llx %llu~%u"
1012                                 "got EOLDSNAPC, retrying\n",
1013                                 inode, ceph_vinop(inode),
1014                                 pos, (unsigned)count);
1015                         mutex_lock(&inode->i_mutex);
1016                         goto retry_snap;
1017                 }
1018                 if (written > 0)
1019                         iov_iter_advance(from, written);
1020         } else {
1021                 loff_t old_size = inode->i_size;
1022                 /*
1023                  * No need to acquire the i_truncate_mutex. Because
1024                  * the MDS revokes Fwb caps before sending truncate
1025                  * message to us. We can't get Fwb cap while there
1026                  * are pending vmtruncate. So write and vmtruncate
1027                  * can not run at the same time
1028                  */
1029                 written = generic_perform_write(file, from, pos);
1030                 if (likely(written >= 0))
1031                         iocb->ki_pos = pos + written;
1032                 if (inode->i_size > old_size)
1033                         ceph_fscache_update_objectsize(inode);
1034                 mutex_unlock(&inode->i_mutex);
1035         }
1036 
1037         if (written >= 0) {
1038                 int dirty;
1039                 spin_lock(&ci->i_ceph_lock);
1040                 ci->i_inline_version = CEPH_INLINE_NONE;
1041                 dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_FILE_WR);
1042                 spin_unlock(&ci->i_ceph_lock);
1043                 if (dirty)
1044                         __mark_inode_dirty(inode, dirty);
1045         }
1046 
1047         dout("aio_write %p %llx.%llx %llu~%u  dropping cap refs on %s\n",
1048              inode, ceph_vinop(inode), pos, (unsigned)count,
1049              ceph_cap_string(got));
1050         ceph_put_cap_refs(ci, got);
1051 
1052         if (written >= 0 &&
1053             ((file->f_flags & O_SYNC) || IS_SYNC(file->f_mapping->host) ||
1054              ceph_osdmap_flag(osdc->osdmap, CEPH_OSDMAP_NEARFULL))) {
1055                 err = vfs_fsync_range(file, pos, pos + written - 1, 1);
1056                 if (err < 0)
1057                         written = err;
1058         }
1059 
1060         goto out_unlocked;
1061 
1062 out:
1063         mutex_unlock(&inode->i_mutex);
1064 out_unlocked:
1065         current->backing_dev_info = NULL;
1066         return written ? written : err;
1067 }
1068 
1069 /*
1070  * llseek.  be sure to verify file size on SEEK_END.
1071  */
1072 static loff_t ceph_llseek(struct file *file, loff_t offset, int whence)
1073 {
1074         struct inode *inode = file->f_mapping->host;
1075         int ret;
1076 
1077         mutex_lock(&inode->i_mutex);
1078 
1079         if (whence == SEEK_END || whence == SEEK_DATA || whence == SEEK_HOLE) {
1080                 ret = ceph_do_getattr(inode, CEPH_STAT_CAP_SIZE, false);
1081                 if (ret < 0) {
1082                         offset = ret;
1083                         goto out;
1084                 }
1085         }
1086 
1087         switch (whence) {
1088         case SEEK_END:
1089                 offset += inode->i_size;
1090                 break;
1091         case SEEK_CUR:
1092                 /*
1093                  * Here we special-case the lseek(fd, 0, SEEK_CUR)
1094                  * position-querying operation.  Avoid rewriting the "same"
1095                  * f_pos value back to the file because a concurrent read(),
1096                  * write() or lseek() might have altered it
1097                  */
1098                 if (offset == 0) {
1099                         offset = file->f_pos;
1100                         goto out;
1101                 }
1102                 offset += file->f_pos;
1103                 break;
1104         case SEEK_DATA:
1105                 if (offset >= inode->i_size) {
1106                         ret = -ENXIO;
1107                         goto out;
1108                 }
1109                 break;
1110         case SEEK_HOLE:
1111                 if (offset >= inode->i_size) {
1112                         ret = -ENXIO;
1113                         goto out;
1114                 }
1115                 offset = inode->i_size;
1116                 break;
1117         }
1118 
1119         offset = vfs_setpos(file, offset, inode->i_sb->s_maxbytes);
1120 
1121 out:
1122         mutex_unlock(&inode->i_mutex);
1123         return offset;
1124 }
1125 
1126 static inline void ceph_zero_partial_page(
1127         struct inode *inode, loff_t offset, unsigned size)
1128 {
1129         struct page *page;
1130         pgoff_t index = offset >> PAGE_CACHE_SHIFT;
1131 
1132         page = find_lock_page(inode->i_mapping, index);
1133         if (page) {
1134                 wait_on_page_writeback(page);
1135                 zero_user(page, offset & (PAGE_CACHE_SIZE - 1), size);
1136                 unlock_page(page);
1137                 page_cache_release(page);
1138         }
1139 }
1140 
1141 static void ceph_zero_pagecache_range(struct inode *inode, loff_t offset,
1142                                       loff_t length)
1143 {
1144         loff_t nearly = round_up(offset, PAGE_CACHE_SIZE);
1145         if (offset < nearly) {
1146                 loff_t size = nearly - offset;
1147                 if (length < size)
1148                         size = length;
1149                 ceph_zero_partial_page(inode, offset, size);
1150                 offset += size;
1151                 length -= size;
1152         }
1153         if (length >= PAGE_CACHE_SIZE) {
1154                 loff_t size = round_down(length, PAGE_CACHE_SIZE);
1155                 truncate_pagecache_range(inode, offset, offset + size - 1);
1156                 offset += size;
1157                 length -= size;
1158         }
1159         if (length)
1160                 ceph_zero_partial_page(inode, offset, length);
1161 }
1162 
1163 static int ceph_zero_partial_object(struct inode *inode,
1164                                     loff_t offset, loff_t *length)
1165 {
1166         struct ceph_inode_info *ci = ceph_inode(inode);
1167         struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
1168         struct ceph_osd_request *req;
1169         int ret = 0;
1170         loff_t zero = 0;
1171         int op;
1172 
1173         if (!length) {
1174                 op = offset ? CEPH_OSD_OP_DELETE : CEPH_OSD_OP_TRUNCATE;
1175                 length = &zero;
1176         } else {
1177                 op = CEPH_OSD_OP_ZERO;
1178         }
1179 
1180         req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout,
1181                                         ceph_vino(inode),
1182                                         offset, length,
1183                                         0, 1, op,
1184                                         CEPH_OSD_FLAG_WRITE |
1185                                         CEPH_OSD_FLAG_ONDISK,
1186                                         NULL, 0, 0, false);
1187         if (IS_ERR(req)) {
1188                 ret = PTR_ERR(req);
1189                 goto out;
1190         }
1191 
1192         ceph_osdc_build_request(req, offset, NULL, ceph_vino(inode).snap,
1193                                 &inode->i_mtime);
1194 
1195         ret = ceph_osdc_start_request(&fsc->client->osdc, req, false);
1196         if (!ret) {
1197                 ret = ceph_osdc_wait_request(&fsc->client->osdc, req);
1198                 if (ret == -ENOENT)
1199                         ret = 0;
1200         }
1201         ceph_osdc_put_request(req);
1202 
1203 out:
1204         return ret;
1205 }
1206 
1207 static int ceph_zero_objects(struct inode *inode, loff_t offset, loff_t length)
1208 {
1209         int ret = 0;
1210         struct ceph_inode_info *ci = ceph_inode(inode);
1211         s32 stripe_unit = ceph_file_layout_su(ci->i_layout);
1212         s32 stripe_count = ceph_file_layout_stripe_count(ci->i_layout);
1213         s32 object_size = ceph_file_layout_object_size(ci->i_layout);
1214         u64 object_set_size = object_size * stripe_count;
1215         u64 nearly, t;
1216 
1217         /* round offset up to next period boundary */
1218         nearly = offset + object_set_size - 1;
1219         t = nearly;
1220         nearly -= do_div(t, object_set_size);
1221 
1222         while (length && offset < nearly) {
1223                 loff_t size = length;
1224                 ret = ceph_zero_partial_object(inode, offset, &size);
1225                 if (ret < 0)
1226                         return ret;
1227                 offset += size;
1228                 length -= size;
1229         }
1230         while (length >= object_set_size) {
1231                 int i;
1232                 loff_t pos = offset;
1233                 for (i = 0; i < stripe_count; ++i) {
1234                         ret = ceph_zero_partial_object(inode, pos, NULL);
1235                         if (ret < 0)
1236                                 return ret;
1237                         pos += stripe_unit;
1238                 }
1239                 offset += object_set_size;
1240                 length -= object_set_size;
1241         }
1242         while (length) {
1243                 loff_t size = length;
1244                 ret = ceph_zero_partial_object(inode, offset, &size);
1245                 if (ret < 0)
1246                         return ret;
1247                 offset += size;
1248                 length -= size;
1249         }
1250         return ret;
1251 }
1252 
1253 static long ceph_fallocate(struct file *file, int mode,
1254                                 loff_t offset, loff_t length)
1255 {
1256         struct ceph_file_info *fi = file->private_data;
1257         struct inode *inode = file_inode(file);
1258         struct ceph_inode_info *ci = ceph_inode(inode);
1259         struct ceph_osd_client *osdc =
1260                 &ceph_inode_to_client(inode)->client->osdc;
1261         int want, got = 0;
1262         int dirty;
1263         int ret = 0;
1264         loff_t endoff = 0;
1265         loff_t size;
1266 
1267         if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE))
1268                 return -EOPNOTSUPP;
1269 
1270         if (!S_ISREG(inode->i_mode))
1271                 return -EOPNOTSUPP;
1272 
1273         mutex_lock(&inode->i_mutex);
1274 
1275         if (ceph_snap(inode) != CEPH_NOSNAP) {
1276                 ret = -EROFS;
1277                 goto unlock;
1278         }
1279 
1280         if (ceph_osdmap_flag(osdc->osdmap, CEPH_OSDMAP_FULL) &&
1281                 !(mode & FALLOC_FL_PUNCH_HOLE)) {
1282                 ret = -ENOSPC;
1283                 goto unlock;
1284         }
1285 
1286         if (ci->i_inline_version != CEPH_INLINE_NONE) {
1287                 ret = ceph_uninline_data(file, NULL);
1288                 if (ret < 0)
1289                         goto unlock;
1290         }
1291 
1292         size = i_size_read(inode);
1293         if (!(mode & FALLOC_FL_KEEP_SIZE))
1294                 endoff = offset + length;
1295 
1296         if (fi->fmode & CEPH_FILE_MODE_LAZY)
1297                 want = CEPH_CAP_FILE_BUFFER | CEPH_CAP_FILE_LAZYIO;
1298         else
1299                 want = CEPH_CAP_FILE_BUFFER;
1300 
1301         ret = ceph_get_caps(ci, CEPH_CAP_FILE_WR, want, endoff, &got, NULL);
1302         if (ret < 0)
1303                 goto unlock;
1304 
1305         if (mode & FALLOC_FL_PUNCH_HOLE) {
1306                 if (offset < size)
1307                         ceph_zero_pagecache_range(inode, offset, length);
1308                 ret = ceph_zero_objects(inode, offset, length);
1309         } else if (endoff > size) {
1310                 truncate_pagecache_range(inode, size, -1);
1311                 if (ceph_inode_set_size(inode, endoff))
1312                         ceph_check_caps(ceph_inode(inode),
1313                                 CHECK_CAPS_AUTHONLY, NULL);
1314         }
1315 
1316         if (!ret) {
1317                 spin_lock(&ci->i_ceph_lock);
1318                 ci->i_inline_version = CEPH_INLINE_NONE;
1319                 dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_FILE_WR);
1320                 spin_unlock(&ci->i_ceph_lock);
1321                 if (dirty)
1322                         __mark_inode_dirty(inode, dirty);
1323         }
1324 
1325         ceph_put_cap_refs(ci, got);
1326 unlock:
1327         mutex_unlock(&inode->i_mutex);
1328         return ret;
1329 }
1330 
1331 const struct file_operations ceph_file_fops = {
1332         .open = ceph_open,
1333         .release = ceph_release,
1334         .llseek = ceph_llseek,
1335         .read = new_sync_read,
1336         .write = new_sync_write,
1337         .read_iter = ceph_read_iter,
1338         .write_iter = ceph_write_iter,
1339         .mmap = ceph_mmap,
1340         .fsync = ceph_fsync,
1341         .lock = ceph_lock,
1342         .flock = ceph_flock,
1343         .splice_read = generic_file_splice_read,
1344         .splice_write = iter_file_splice_write,
1345         .unlocked_ioctl = ceph_ioctl,
1346         .compat_ioctl   = ceph_ioctl,
1347         .fallocate      = ceph_fallocate,
1348 };
1349 
1350 

~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

kernel.org | git.kernel.org | LWN.net | Project Home | Wiki (Japanese) | Wiki (English) | SVN repository | Mail admin

Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.

osdn.jp