db4484a3efccc07add8751ce87911e8acf33525b
[deliverable/linux.git] / fs / gfs2 / ops_file.c
1 /*
2 * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
3 * Copyright (C) 2004-2005 Red Hat, Inc. All rights reserved.
4 *
5 * This copyrighted material is made available to anyone wishing to use,
6 * modify, copy, or redistribute it subject to the terms and conditions
7 * of the GNU General Public License v.2.
8 */
9
10 #include <linux/sched.h>
11 #include <linux/slab.h>
12 #include <linux/spinlock.h>
13 #include <linux/completion.h>
14 #include <linux/buffer_head.h>
15 #include <linux/pagemap.h>
16 #include <linux/uio.h>
17 #include <linux/blkdev.h>
18 #include <linux/mm.h>
19 #include <linux/smp_lock.h>
20 #include <linux/fs.h>
21 #include <linux/gfs2_ondisk.h>
22 #include <linux/ext2_fs.h>
23 #include <linux/crc32.h>
24 #include <linux/iflags.h>
25 #include <asm/semaphore.h>
26 #include <asm/uaccess.h>
27
28 #include "gfs2.h"
29 #include "lm_interface.h"
30 #include "incore.h"
31 #include "bmap.h"
32 #include "dir.h"
33 #include "glock.h"
34 #include "glops.h"
35 #include "inode.h"
36 #include "lm.h"
37 #include "log.h"
38 #include "meta_io.h"
39 #include "ops_file.h"
40 #include "ops_vm.h"
41 #include "quota.h"
42 #include "rgrp.h"
43 #include "trans.h"
44 #include "util.h"
45 #include "eaops.h"
46
47 /* "bad" is for NFS support */
48 struct filldir_bad_entry {
49 char *fbe_name;
50 unsigned int fbe_length;
51 uint64_t fbe_offset;
52 struct gfs2_inum fbe_inum;
53 unsigned int fbe_type;
54 };
55
56 struct filldir_bad {
57 struct gfs2_sbd *fdb_sbd;
58
59 struct filldir_bad_entry *fdb_entry;
60 unsigned int fdb_entry_num;
61 unsigned int fdb_entry_off;
62
63 char *fdb_name;
64 unsigned int fdb_name_size;
65 unsigned int fdb_name_off;
66 };
67
68 /* For regular, non-NFS */
69 struct filldir_reg {
70 struct gfs2_sbd *fdr_sbd;
71 int fdr_prefetch;
72
73 filldir_t fdr_filldir;
74 void *fdr_opaque;
75 };
76
77 /*
78 * Most fields left uninitialised to catch anybody who tries to
79 * use them. f_flags set to prevent file_accessed() from touching
80 * any other part of this. Its use is purely as a flag so that we
81 * know (in readpage()) whether or not do to locking.
82 */
83 struct file gfs2_internal_file_sentinal = {
84 .f_flags = O_NOATIME|O_RDONLY,
85 };
86
87 static int gfs2_read_actor(read_descriptor_t *desc, struct page *page,
88 unsigned long offset, unsigned long size)
89 {
90 char *kaddr;
91 unsigned long count = desc->count;
92
93 if (size > count)
94 size = count;
95
96 kaddr = kmap(page);
97 memcpy(desc->arg.buf, kaddr + offset, size);
98 kunmap(page);
99
100 desc->count = count - size;
101 desc->written += size;
102 desc->arg.buf += size;
103 return size;
104 }
105
106 int gfs2_internal_read(struct gfs2_inode *ip, struct file_ra_state *ra_state,
107 char *buf, loff_t *pos, unsigned size)
108 {
109 struct inode *inode = ip->i_vnode;
110 read_descriptor_t desc;
111 desc.written = 0;
112 desc.arg.buf = buf;
113 desc.count = size;
114 desc.error = 0;
115 do_generic_mapping_read(inode->i_mapping, ra_state,
116 &gfs2_internal_file_sentinal, pos, &desc,
117 gfs2_read_actor);
118 return desc.written ? desc.written : desc.error;
119 }
120
121 /**
122 * gfs2_llseek - seek to a location in a file
123 * @file: the file
124 * @offset: the offset
125 * @origin: Where to seek from (SEEK_SET, SEEK_CUR, or SEEK_END)
126 *
127 * SEEK_END requires the glock for the file because it references the
128 * file's size.
129 *
130 * Returns: The new offset, or errno
131 */
132
133 static loff_t gfs2_llseek(struct file *file, loff_t offset, int origin)
134 {
135 struct gfs2_inode *ip = file->f_mapping->host->u.generic_ip;
136 struct gfs2_holder i_gh;
137 loff_t error;
138
139 if (origin == 2) {
140 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY,
141 &i_gh);
142 if (!error) {
143 error = remote_llseek(file, offset, origin);
144 gfs2_glock_dq_uninit(&i_gh);
145 }
146 } else
147 error = remote_llseek(file, offset, origin);
148
149 return error;
150 }
151
152
153 static ssize_t gfs2_direct_IO_read(struct kiocb *iocb, const struct iovec *iov,
154 loff_t offset, unsigned long nr_segs)
155 {
156 struct file *file = iocb->ki_filp;
157 struct address_space *mapping = file->f_mapping;
158 ssize_t retval;
159
160 retval = filemap_write_and_wait(mapping);
161 if (retval == 0) {
162 retval = mapping->a_ops->direct_IO(READ, iocb, iov, offset,
163 nr_segs);
164 }
165 return retval;
166 }
167
168 /**
169 * __gfs2_file_aio_read - The main GFS2 read function
170 *
171 * N.B. This is almost, but not quite the same as __generic_file_aio_read()
172 * the important subtle different being that inode->i_size isn't valid
173 * unless we are holding a lock, and we do this _only_ on the O_DIRECT
174 * path since otherwise locking is done entirely at the page cache
175 * layer.
176 */
177 static ssize_t __gfs2_file_aio_read(struct kiocb *iocb,
178 const struct iovec *iov,
179 unsigned long nr_segs, loff_t *ppos)
180 {
181 struct file *filp = iocb->ki_filp;
182 struct gfs2_inode *ip = filp->f_mapping->host->u.generic_ip;
183 struct gfs2_holder gh;
184 ssize_t retval;
185 unsigned long seg;
186 size_t count;
187
188 count = 0;
189 for (seg = 0; seg < nr_segs; seg++) {
190 const struct iovec *iv = &iov[seg];
191
192 /*
193 * If any segment has a negative length, or the cumulative
194 * length ever wraps negative then return -EINVAL.
195 */
196 count += iv->iov_len;
197 if (unlikely((ssize_t)(count|iv->iov_len) < 0))
198 return -EINVAL;
199 if (access_ok(VERIFY_WRITE, iv->iov_base, iv->iov_len))
200 continue;
201 if (seg == 0)
202 return -EFAULT;
203 nr_segs = seg;
204 count -= iv->iov_len; /* This segment is no good */
205 break;
206 }
207
208 /* coalesce the iovecs and go direct-to-BIO for O_DIRECT */
209 if (filp->f_flags & O_DIRECT) {
210 loff_t pos = *ppos, size;
211 struct address_space *mapping;
212 struct inode *inode;
213
214 mapping = filp->f_mapping;
215 inode = mapping->host;
216 retval = 0;
217 if (!count)
218 goto out; /* skip atime */
219
220 gfs2_holder_init(ip->i_gl, LM_ST_SHARED, GL_ATIME, &gh);
221 retval = gfs2_glock_nq_m_atime(1, &gh);
222 if (retval)
223 goto out;
224 if (gfs2_is_stuffed(ip)) {
225 gfs2_glock_dq_m(1, &gh);
226 gfs2_holder_uninit(&gh);
227 goto fallback_to_normal;
228 }
229 size = i_size_read(inode);
230 if (pos < size) {
231 retval = gfs2_direct_IO_read(iocb, iov, pos, nr_segs);
232 if (retval > 0 && !is_sync_kiocb(iocb))
233 retval = -EIOCBQUEUED;
234 if (retval > 0)
235 *ppos = pos + retval;
236 }
237 file_accessed(filp);
238 gfs2_glock_dq_m(1, &gh);
239 gfs2_holder_uninit(&gh);
240 goto out;
241 }
242
243 fallback_to_normal:
244 retval = 0;
245 if (count) {
246 for (seg = 0; seg < nr_segs; seg++) {
247 read_descriptor_t desc;
248
249 desc.written = 0;
250 desc.arg.buf = iov[seg].iov_base;
251 desc.count = iov[seg].iov_len;
252 if (desc.count == 0)
253 continue;
254 desc.error = 0;
255 do_generic_file_read(filp,ppos,&desc,file_read_actor);
256 retval += desc.written;
257 if (desc.error) {
258 retval = retval ?: desc.error;
259 break;
260 }
261 }
262 }
263 out:
264 return retval;
265 }
266
267 /**
268 * gfs2_read - Read bytes from a file
269 * @file: The file to read from
270 * @buf: The buffer to copy into
271 * @size: The amount of data requested
272 * @offset: The current file offset
273 *
274 * Outputs: Offset - updated according to number of bytes read
275 *
276 * Returns: The number of bytes read, errno on failure
277 */
278
279 static ssize_t gfs2_read(struct file *filp, char __user *buf, size_t size,
280 loff_t *offset)
281 {
282 struct iovec local_iov = { .iov_base = buf, .iov_len = size };
283 struct kiocb kiocb;
284 ssize_t ret;
285
286 init_sync_kiocb(&kiocb, filp);
287 ret = __gfs2_file_aio_read(&kiocb, &local_iov, 1, offset);
288 if (-EIOCBQUEUED == ret)
289 ret = wait_on_sync_kiocb(&kiocb);
290 return ret;
291 }
292
293 static ssize_t gfs2_file_readv(struct file *filp, const struct iovec *iov,
294 unsigned long nr_segs, loff_t *ppos)
295 {
296 struct kiocb kiocb;
297 ssize_t ret;
298
299 init_sync_kiocb(&kiocb, filp);
300 ret = __gfs2_file_aio_read(&kiocb, iov, nr_segs, ppos);
301 if (-EIOCBQUEUED == ret)
302 ret = wait_on_sync_kiocb(&kiocb);
303 return ret;
304 }
305
306 static ssize_t gfs2_file_aio_read(struct kiocb *iocb, char __user *buf,
307 size_t count, loff_t pos)
308 {
309 struct iovec local_iov = { .iov_base = buf, .iov_len = count };
310
311 BUG_ON(iocb->ki_pos != pos);
312 return __gfs2_file_aio_read(iocb, &local_iov, 1, &iocb->ki_pos);
313 }
314
315
316 /**
317 * filldir_reg_func - Report a directory entry to the caller of gfs2_dir_read()
318 * @opaque: opaque data used by the function
319 * @name: the name of the directory entry
320 * @length: the length of the name
321 * @offset: the entry's offset in the directory
322 * @inum: the inode number the entry points to
323 * @type: the type of inode the entry points to
324 *
325 * Returns: 0 on success, 1 if buffer full
326 */
327
328 static int filldir_reg_func(void *opaque, const char *name, unsigned int length,
329 uint64_t offset, struct gfs2_inum *inum,
330 unsigned int type)
331 {
332 struct filldir_reg *fdr = (struct filldir_reg *)opaque;
333 struct gfs2_sbd *sdp = fdr->fdr_sbd;
334 int error;
335
336 error = fdr->fdr_filldir(fdr->fdr_opaque, name, length, offset,
337 inum->no_formal_ino, type);
338 if (error)
339 return 1;
340
341 if (fdr->fdr_prefetch && !(length == 1 && *name == '.')) {
342 gfs2_glock_prefetch_num(sdp,
343 inum->no_addr, &gfs2_inode_glops,
344 LM_ST_SHARED, LM_FLAG_TRY | LM_FLAG_ANY);
345 gfs2_glock_prefetch_num(sdp,
346 inum->no_addr, &gfs2_iopen_glops,
347 LM_ST_SHARED, LM_FLAG_TRY);
348 }
349
350 return 0;
351 }
352
353 /**
354 * readdir_reg - Read directory entries from a directory
355 * @file: The directory to read from
356 * @dirent: Buffer for dirents
357 * @filldir: Function used to do the copying
358 *
359 * Returns: errno
360 */
361
362 static int readdir_reg(struct file *file, void *dirent, filldir_t filldir)
363 {
364 struct inode *dir = file->f_mapping->host;
365 struct gfs2_inode *dip = dir->u.generic_ip;
366 struct filldir_reg fdr;
367 struct gfs2_holder d_gh;
368 uint64_t offset = file->f_pos;
369 int error;
370
371 fdr.fdr_sbd = dip->i_sbd;
372 fdr.fdr_prefetch = 1;
373 fdr.fdr_filldir = filldir;
374 fdr.fdr_opaque = dirent;
375
376 gfs2_holder_init(dip->i_gl, LM_ST_SHARED, GL_ATIME, &d_gh);
377 error = gfs2_glock_nq_atime(&d_gh);
378 if (error) {
379 gfs2_holder_uninit(&d_gh);
380 return error;
381 }
382
383 error = gfs2_dir_read(dir, &offset, &fdr, filldir_reg_func);
384
385 gfs2_glock_dq_uninit(&d_gh);
386
387 file->f_pos = offset;
388
389 return error;
390 }
391
392 /**
393 * filldir_bad_func - Report a directory entry to the caller of gfs2_dir_read()
394 * @opaque: opaque data used by the function
395 * @name: the name of the directory entry
396 * @length: the length of the name
397 * @offset: the entry's offset in the directory
398 * @inum: the inode number the entry points to
399 * @type: the type of inode the entry points to
400 *
401 * For supporting NFS.
402 *
403 * Returns: 0 on success, 1 if buffer full
404 */
405
406 static int filldir_bad_func(void *opaque, const char *name, unsigned int length,
407 uint64_t offset, struct gfs2_inum *inum,
408 unsigned int type)
409 {
410 struct filldir_bad *fdb = (struct filldir_bad *)opaque;
411 struct gfs2_sbd *sdp = fdb->fdb_sbd;
412 struct filldir_bad_entry *fbe;
413
414 if (fdb->fdb_entry_off == fdb->fdb_entry_num ||
415 fdb->fdb_name_off + length > fdb->fdb_name_size)
416 return 1;
417
418 fbe = &fdb->fdb_entry[fdb->fdb_entry_off];
419 fbe->fbe_name = fdb->fdb_name + fdb->fdb_name_off;
420 memcpy(fbe->fbe_name, name, length);
421 fbe->fbe_length = length;
422 fbe->fbe_offset = offset;
423 fbe->fbe_inum = *inum;
424 fbe->fbe_type = type;
425
426 fdb->fdb_entry_off++;
427 fdb->fdb_name_off += length;
428
429 if (!(length == 1 && *name == '.')) {
430 gfs2_glock_prefetch_num(sdp,
431 inum->no_addr, &gfs2_inode_glops,
432 LM_ST_SHARED, LM_FLAG_TRY | LM_FLAG_ANY);
433 gfs2_glock_prefetch_num(sdp,
434 inum->no_addr, &gfs2_iopen_glops,
435 LM_ST_SHARED, LM_FLAG_TRY);
436 }
437
438 return 0;
439 }
440
441 /**
442 * readdir_bad - Read directory entries from a directory
443 * @file: The directory to read from
444 * @dirent: Buffer for dirents
445 * @filldir: Function used to do the copying
446 *
447 * For supporting NFS.
448 *
449 * Returns: errno
450 */
451
452 static int readdir_bad(struct file *file, void *dirent, filldir_t filldir)
453 {
454 struct inode *dir = file->f_mapping->host;
455 struct gfs2_inode *dip = dir->u.generic_ip;
456 struct gfs2_sbd *sdp = dip->i_sbd;
457 struct filldir_reg fdr;
458 unsigned int entries, size;
459 struct filldir_bad *fdb;
460 struct gfs2_holder d_gh;
461 uint64_t offset = file->f_pos;
462 unsigned int x;
463 struct filldir_bad_entry *fbe;
464 int error;
465
466 entries = gfs2_tune_get(sdp, gt_entries_per_readdir);
467 size = sizeof(struct filldir_bad) +
468 entries * (sizeof(struct filldir_bad_entry) + GFS2_FAST_NAME_SIZE);
469
470 fdb = kzalloc(size, GFP_KERNEL);
471 if (!fdb)
472 return -ENOMEM;
473
474 fdb->fdb_sbd = sdp;
475 fdb->fdb_entry = (struct filldir_bad_entry *)(fdb + 1);
476 fdb->fdb_entry_num = entries;
477 fdb->fdb_name = ((char *)fdb) + sizeof(struct filldir_bad) +
478 entries * sizeof(struct filldir_bad_entry);
479 fdb->fdb_name_size = entries * GFS2_FAST_NAME_SIZE;
480
481 gfs2_holder_init(dip->i_gl, LM_ST_SHARED, GL_ATIME, &d_gh);
482 error = gfs2_glock_nq_atime(&d_gh);
483 if (error) {
484 gfs2_holder_uninit(&d_gh);
485 goto out;
486 }
487
488 error = gfs2_dir_read(dir, &offset, fdb, filldir_bad_func);
489
490 gfs2_glock_dq_uninit(&d_gh);
491
492 fdr.fdr_sbd = sdp;
493 fdr.fdr_prefetch = 0;
494 fdr.fdr_filldir = filldir;
495 fdr.fdr_opaque = dirent;
496
497 for (x = 0; x < fdb->fdb_entry_off; x++) {
498 fbe = &fdb->fdb_entry[x];
499
500 error = filldir_reg_func(&fdr,
501 fbe->fbe_name, fbe->fbe_length,
502 fbe->fbe_offset,
503 &fbe->fbe_inum, fbe->fbe_type);
504 if (error) {
505 file->f_pos = fbe->fbe_offset;
506 error = 0;
507 goto out;
508 }
509 }
510
511 file->f_pos = offset;
512
513 out:
514 kfree(fdb);
515
516 return error;
517 }
518
519 /**
520 * gfs2_readdir - Read directory entries from a directory
521 * @file: The directory to read from
522 * @dirent: Buffer for dirents
523 * @filldir: Function used to do the copying
524 *
525 * Returns: errno
526 */
527
528 static int gfs2_readdir(struct file *file, void *dirent, filldir_t filldir)
529 {
530 int error;
531
532 if (strcmp(current->comm, "nfsd") != 0)
533 error = readdir_reg(file, dirent, filldir);
534 else
535 error = readdir_bad(file, dirent, filldir);
536
537 return error;
538 }
539
540 static const u32 iflags_to_gfs2[32] = {
541 [iflag_Sync] = GFS2_DIF_SYNC,
542 [iflag_Immutable] = GFS2_DIF_IMMUTABLE,
543 [iflag_Append] = GFS2_DIF_APPENDONLY,
544 [iflag_NoAtime] = GFS2_DIF_NOATIME,
545 [iflag_Index] = GFS2_DIF_EXHASH,
546 [iflag_JournalData] = GFS2_DIF_JDATA,
547 [iflag_DirectIO] = GFS2_DIF_DIRECTIO,
548 [iflag_InheritDirectIO] = GFS2_DIF_INHERIT_DIRECTIO,
549 [iflag_InheritJdata] = GFS2_DIF_INHERIT_JDATA,
550 };
551
552 static const u32 gfs2_to_iflags[32] = {
553 [gfs2fl_Sync] = IFLAG_SYNC,
554 [gfs2fl_Immutable] = IFLAG_IMMUTABLE,
555 [gfs2fl_AppendOnly] = IFLAG_APPEND,
556 [gfs2fl_NoAtime] = IFLAG_NOATIME,
557 [gfs2fl_ExHash] = IFLAG_INDEX,
558 [gfs2fl_Jdata] = IFLAG_JOURNAL_DATA,
559 [gfs2fl_Directio] = IFLAG_DIRECTIO,
560 [gfs2fl_InheritDirectio] = IFLAG_INHERITDIRECTIO,
561 [gfs2fl_InheritJdata] = IFLAG_INHERITJDATA,
562 };
563
564 static int gfs2_get_flags(struct inode *inode, u32 __user *ptr)
565 {
566 struct gfs2_inode *ip = inode->u.generic_ip;
567 struct gfs2_holder gh;
568 int error;
569 u32 iflags;
570
571 gfs2_holder_init(ip->i_gl, LM_ST_SHARED, GL_ATIME, &gh);
572 error = gfs2_glock_nq_m_atime(1, &gh);
573 if (error)
574 return error;
575
576 iflags = iflags_cvt(gfs2_to_iflags, ip->i_di.di_flags);
577 if (put_user(iflags, ptr))
578 error = -EFAULT;
579
580 gfs2_glock_dq_m(1, &gh);
581 gfs2_holder_uninit(&gh);
582 return error;
583 }
584
585 /* Flags that can be set by user space */
586 #define GFS2_FLAGS_USER_SET (GFS2_DIF_JDATA| \
587 GFS2_DIF_DIRECTIO| \
588 GFS2_DIF_IMMUTABLE| \
589 GFS2_DIF_APPENDONLY| \
590 GFS2_DIF_NOATIME| \
591 GFS2_DIF_SYNC| \
592 GFS2_DIF_SYSTEM| \
593 GFS2_DIF_INHERIT_DIRECTIO| \
594 GFS2_DIF_INHERIT_JDATA)
595
596 /**
597 * gfs2_set_flags - set flags on an inode
598 * @inode: The inode
599 * @flags: The flags to set
600 * @mask: Indicates which flags are valid
601 *
602 */
603 static int do_gfs2_set_flags(struct inode *inode, u32 flags, u32 mask)
604 {
605 struct gfs2_inode *ip = inode->u.generic_ip;
606 struct buffer_head *bh;
607 struct gfs2_holder gh;
608 int error;
609 u32 new_flags;
610
611 gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
612 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
613 if (error)
614 return error;
615
616 new_flags = (ip->i_di.di_flags & ~mask) | (flags & mask);
617 if ((new_flags ^ flags) == 0)
618 goto out;
619
620 error = -EINVAL;
621 if ((new_flags ^ flags) & ~GFS2_FLAGS_USER_SET)
622 goto out;
623
624 if (S_ISDIR(inode->i_mode)) {
625 if ((new_flags ^ flags) & (GFS2_DIF_JDATA | GFS2_DIF_DIRECTIO))
626 goto out;
627 } else if (S_ISREG(inode->i_mode)) {
628 if ((new_flags ^ flags) & (GFS2_DIF_INHERIT_DIRECTIO|
629 GFS2_DIF_INHERIT_JDATA))
630 goto out;
631 } else
632 goto out;
633
634 error = -EPERM;
635 if (IS_IMMUTABLE(inode) && (new_flags & GFS2_DIF_IMMUTABLE))
636 goto out;
637 if (IS_APPEND(inode) && (new_flags & GFS2_DIF_APPENDONLY))
638 goto out;
639 error = gfs2_repermission(inode, MAY_WRITE, NULL);
640 if (error)
641 goto out;
642
643 error = gfs2_meta_inode_buffer(ip, &bh);
644 if (error)
645 goto out;
646 gfs2_trans_add_bh(ip->i_gl, bh, 1);
647 ip->i_di.di_flags = new_flags;
648 gfs2_dinode_out(&ip->i_di, bh->b_data);
649 brelse(bh);
650 out:
651 gfs2_glock_dq_uninit(&gh);
652 return error;
653 }
654
655 static int gfs2_set_flags(struct inode *inode, u32 __user *ptr)
656 {
657 u32 iflags, gfsflags;
658 if (get_user(iflags, ptr))
659 return -EFAULT;
660 gfsflags = iflags_cvt(iflags_to_gfs2, iflags);
661 return do_gfs2_set_flags(inode, gfsflags, ~0);
662 }
663
664 int gfs2_ioctl(struct inode *inode, struct file *filp, unsigned int cmd,
665 unsigned long arg)
666 {
667 switch(cmd) {
668 case IFLAGS_GET_IOC:
669 return gfs2_get_flags(inode, (u32 __user *)arg);
670 case IFLAGS_SET_IOC:
671 return gfs2_set_flags(inode, (u32 __user *)arg);
672 }
673 return -ENOTTY;
674 }
675
676
677 /**
678 * gfs2_mmap -
679 * @file: The file to map
680 * @vma: The VMA which described the mapping
681 *
682 * Returns: 0 or error code
683 */
684
685 static int gfs2_mmap(struct file *file, struct vm_area_struct *vma)
686 {
687 struct gfs2_inode *ip = file->f_mapping->host->u.generic_ip;
688 struct gfs2_holder i_gh;
689 int error;
690
691 gfs2_holder_init(ip->i_gl, LM_ST_SHARED, GL_ATIME, &i_gh);
692 error = gfs2_glock_nq_atime(&i_gh);
693 if (error) {
694 gfs2_holder_uninit(&i_gh);
695 return error;
696 }
697
698 /* This is VM_MAYWRITE instead of VM_WRITE because a call
699 to mprotect() can turn on VM_WRITE later. */
700
701 if ((vma->vm_flags & (VM_MAYSHARE | VM_MAYWRITE)) ==
702 (VM_MAYSHARE | VM_MAYWRITE))
703 vma->vm_ops = &gfs2_vm_ops_sharewrite;
704 else
705 vma->vm_ops = &gfs2_vm_ops_private;
706
707 gfs2_glock_dq_uninit(&i_gh);
708
709 return error;
710 }
711
712 /**
713 * gfs2_open - open a file
714 * @inode: the inode to open
715 * @file: the struct file for this opening
716 *
717 * Returns: errno
718 */
719
720 static int gfs2_open(struct inode *inode, struct file *file)
721 {
722 struct gfs2_inode *ip = inode->u.generic_ip;
723 struct gfs2_holder i_gh;
724 struct gfs2_file *fp;
725 int error;
726
727 fp = kzalloc(sizeof(struct gfs2_file), GFP_KERNEL);
728 if (!fp)
729 return -ENOMEM;
730
731 mutex_init(&fp->f_fl_mutex);
732
733 fp->f_inode = ip;
734 fp->f_vfile = file;
735
736 gfs2_assert_warn(ip->i_sbd, !file->private_data);
737 file->private_data = fp;
738
739 if (S_ISREG(ip->i_di.di_mode)) {
740 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY,
741 &i_gh);
742 if (error)
743 goto fail;
744
745 if (!(file->f_flags & O_LARGEFILE) &&
746 ip->i_di.di_size > MAX_NON_LFS) {
747 error = -EFBIG;
748 goto fail_gunlock;
749 }
750
751 /* Listen to the Direct I/O flag */
752
753 if (ip->i_di.di_flags & GFS2_DIF_DIRECTIO)
754 file->f_flags |= O_DIRECT;
755
756 gfs2_glock_dq_uninit(&i_gh);
757 }
758
759 return 0;
760
761 fail_gunlock:
762 gfs2_glock_dq_uninit(&i_gh);
763
764 fail:
765 file->private_data = NULL;
766 kfree(fp);
767
768 return error;
769 }
770
771 /**
772 * gfs2_close - called to close a struct file
773 * @inode: the inode the struct file belongs to
774 * @file: the struct file being closed
775 *
776 * Returns: errno
777 */
778
779 static int gfs2_close(struct inode *inode, struct file *file)
780 {
781 struct gfs2_sbd *sdp = inode->i_sb->s_fs_info;
782 struct gfs2_file *fp;
783
784 fp = file->private_data;
785 file->private_data = NULL;
786
787 if (gfs2_assert_warn(sdp, fp))
788 return -EIO;
789
790 kfree(fp);
791
792 return 0;
793 }
794
795 /**
796 * gfs2_fsync - sync the dirty data for a file (across the cluster)
797 * @file: the file that points to the dentry (we ignore this)
798 * @dentry: the dentry that points to the inode to sync
799 *
800 * Returns: errno
801 */
802
803 static int gfs2_fsync(struct file *file, struct dentry *dentry, int datasync)
804 {
805 struct gfs2_inode *ip = dentry->d_inode->u.generic_ip;
806
807 gfs2_log_flush_glock(ip->i_gl);
808
809 return 0;
810 }
811
812 /**
813 * gfs2_lock - acquire/release a posix lock on a file
814 * @file: the file pointer
815 * @cmd: either modify or retrieve lock state, possibly wait
816 * @fl: type and range of lock
817 *
818 * Returns: errno
819 */
820
821 static int gfs2_lock(struct file *file, int cmd, struct file_lock *fl)
822 {
823 struct gfs2_inode *ip = file->f_mapping->host->u.generic_ip;
824 struct gfs2_sbd *sdp = ip->i_sbd;
825 struct lm_lockname name =
826 { .ln_number = ip->i_num.no_addr,
827 .ln_type = LM_TYPE_PLOCK };
828
829 if (!(fl->fl_flags & FL_POSIX))
830 return -ENOLCK;
831 if ((ip->i_di.di_mode & (S_ISGID | S_IXGRP)) == S_ISGID)
832 return -ENOLCK;
833
834 if (sdp->sd_args.ar_localflocks) {
835 if (IS_GETLK(cmd)) {
836 struct file_lock *tmp;
837 lock_kernel();
838 tmp = posix_test_lock(file, fl);
839 fl->fl_type = F_UNLCK;
840 if (tmp)
841 memcpy(fl, tmp, sizeof(struct file_lock));
842 unlock_kernel();
843 return 0;
844 } else {
845 int error;
846 lock_kernel();
847 error = posix_lock_file_wait(file, fl);
848 unlock_kernel();
849 return error;
850 }
851 }
852
853 if (IS_GETLK(cmd))
854 return gfs2_lm_plock_get(sdp, &name, file, fl);
855 else if (fl->fl_type == F_UNLCK)
856 return gfs2_lm_punlock(sdp, &name, file, fl);
857 else
858 return gfs2_lm_plock(sdp, &name, file, cmd, fl);
859 }
860
861 /**
862 * gfs2_sendfile - Send bytes to a file or socket
863 * @in_file: The file to read from
864 * @out_file: The file to write to
865 * @count: The amount of data
866 * @offset: The beginning file offset
867 *
868 * Outputs: offset - updated according to number of bytes read
869 *
870 * Returns: The number of bytes sent, errno on failure
871 */
872
873 static ssize_t gfs2_sendfile(struct file *in_file, loff_t *offset, size_t count,
874 read_actor_t actor, void *target)
875 {
876 return generic_file_sendfile(in_file, offset, count, actor, target);
877 }
878
879 static int do_flock(struct file *file, int cmd, struct file_lock *fl)
880 {
881 struct gfs2_file *fp = file->private_data;
882 struct gfs2_holder *fl_gh = &fp->f_fl_gh;
883 struct gfs2_inode *ip = fp->f_inode;
884 struct gfs2_glock *gl;
885 unsigned int state;
886 int flags;
887 int error = 0;
888
889 state = (fl->fl_type == F_WRLCK) ? LM_ST_EXCLUSIVE : LM_ST_SHARED;
890 flags = ((IS_SETLKW(cmd)) ? 0 : LM_FLAG_TRY) | GL_EXACT | GL_NOCACHE;
891
892 mutex_lock(&fp->f_fl_mutex);
893
894 gl = fl_gh->gh_gl;
895 if (gl) {
896 if (fl_gh->gh_state == state)
897 goto out;
898 gfs2_glock_hold(gl);
899 flock_lock_file_wait(file,
900 &(struct file_lock){.fl_type = F_UNLCK});
901 gfs2_glock_dq_uninit(fl_gh);
902 } else {
903 error = gfs2_glock_get(ip->i_sbd,
904 ip->i_num.no_addr, &gfs2_flock_glops,
905 CREATE, &gl);
906 if (error)
907 goto out;
908 }
909
910 gfs2_holder_init(gl, state, flags, fl_gh);
911 gfs2_glock_put(gl);
912
913 error = gfs2_glock_nq(fl_gh);
914 if (error) {
915 gfs2_holder_uninit(fl_gh);
916 if (error == GLR_TRYFAILED)
917 error = -EAGAIN;
918 } else {
919 error = flock_lock_file_wait(file, fl);
920 gfs2_assert_warn(ip->i_sbd, !error);
921 }
922
923 out:
924 mutex_unlock(&fp->f_fl_mutex);
925
926 return error;
927 }
928
929 static void do_unflock(struct file *file, struct file_lock *fl)
930 {
931 struct gfs2_file *fp = file->private_data;
932 struct gfs2_holder *fl_gh = &fp->f_fl_gh;
933
934 mutex_lock(&fp->f_fl_mutex);
935 flock_lock_file_wait(file, fl);
936 if (fl_gh->gh_gl)
937 gfs2_glock_dq_uninit(fl_gh);
938 mutex_unlock(&fp->f_fl_mutex);
939 }
940
941 /**
942 * gfs2_flock - acquire/release a flock lock on a file
943 * @file: the file pointer
944 * @cmd: either modify or retrieve lock state, possibly wait
945 * @fl: type and range of lock
946 *
947 * Returns: errno
948 */
949
950 static int gfs2_flock(struct file *file, int cmd, struct file_lock *fl)
951 {
952 struct gfs2_inode *ip = file->f_mapping->host->u.generic_ip;
953 struct gfs2_sbd *sdp = ip->i_sbd;
954
955 if (!(fl->fl_flags & FL_FLOCK))
956 return -ENOLCK;
957 if ((ip->i_di.di_mode & (S_ISGID | S_IXGRP)) == S_ISGID)
958 return -ENOLCK;
959
960 if (sdp->sd_args.ar_localflocks)
961 return flock_lock_file_wait(file, fl);
962
963 if (fl->fl_type == F_UNLCK) {
964 do_unflock(file, fl);
965 return 0;
966 } else
967 return do_flock(file, cmd, fl);
968 }
969
970 struct file_operations gfs2_file_fops = {
971 .llseek = gfs2_llseek,
972 .read = gfs2_read,
973 .readv = gfs2_file_readv,
974 .aio_read = gfs2_file_aio_read,
975 .write = generic_file_write,
976 .writev = generic_file_writev,
977 .aio_write = generic_file_aio_write,
978 .ioctl = gfs2_ioctl,
979 .mmap = gfs2_mmap,
980 .open = gfs2_open,
981 .release = gfs2_close,
982 .fsync = gfs2_fsync,
983 .lock = gfs2_lock,
984 .sendfile = gfs2_sendfile,
985 .flock = gfs2_flock,
986 };
987
988 struct file_operations gfs2_dir_fops = {
989 .readdir = gfs2_readdir,
990 .ioctl = gfs2_ioctl,
991 .open = gfs2_open,
992 .release = gfs2_close,
993 .fsync = gfs2_fsync,
994 .lock = gfs2_lock,
995 .flock = gfs2_flock,
996 };
997
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