2 * Copyright (c) 2000-2006 Silicon Graphics, Inc.
3 * Copyright (c) 2012-2013 Red Hat, Inc.
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License as
8 * published by the Free Software Foundation.
10 * This program is distributed in the hope that it would be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
20 #include "xfs_shared.h"
22 #include "xfs_format.h"
23 #include "xfs_log_format.h"
24 #include "xfs_trans_resv.h"
28 #include "xfs_mount.h"
29 #include "xfs_da_format.h"
31 #include "xfs_inode.h"
32 #include "xfs_ialloc.h"
33 #include "xfs_alloc.h"
35 #include "xfs_bmap_btree.h"
36 #include "xfs_bmap_util.h"
37 #include "xfs_error.h"
38 #include "xfs_quota.h"
39 #include "xfs_trans_space.h"
40 #include "xfs_trace.h"
41 #include "xfs_symlink.h"
42 #include "xfs_trans.h"
44 #include "xfs_dinode.h"
46 /* ----- Kernel only functions below ----- */
52 struct xfs_mount
*mp
= ip
->i_mount
;
53 struct xfs_bmbt_irec mval
[XFS_SYMLINK_MAPS
];
57 int pathlen
= ip
->i_d
.di_size
;
58 int nmaps
= XFS_SYMLINK_MAPS
;
65 fsblocks
= xfs_symlink_blocks(mp
, pathlen
);
66 error
= xfs_bmapi_read(ip
, 0, fsblocks
, mval
, &nmaps
, 0);
71 for (n
= 0; n
< nmaps
; n
++) {
72 d
= XFS_FSB_TO_DADDR(mp
, mval
[n
].br_startblock
);
73 byte_cnt
= XFS_FSB_TO_B(mp
, mval
[n
].br_blockcount
);
75 bp
= xfs_buf_read(mp
->m_ddev_targp
, d
, BTOBB(byte_cnt
), 0,
76 &xfs_symlink_buf_ops
);
78 return XFS_ERROR(ENOMEM
);
81 xfs_buf_ioerror_alert(bp
, __func__
);
84 /* bad CRC means corrupted metadata */
85 if (error
== EFSBADCRC
)
89 byte_cnt
= XFS_SYMLINK_BUF_SPACE(mp
, byte_cnt
);
90 if (pathlen
< byte_cnt
)
93 cur_chunk
= bp
->b_addr
;
94 if (xfs_sb_version_hascrc(&mp
->m_sb
)) {
95 if (!xfs_symlink_hdr_ok(mp
, ip
->i_ino
, offset
,
99 "symlink header does not match required off/len/owner (0x%x/Ox%x,0x%llx)",
100 offset
, byte_cnt
, ip
->i_ino
);
106 cur_chunk
+= sizeof(struct xfs_dsymlink_hdr
);
109 memcpy(link
+ offset
, bp
->b_addr
, byte_cnt
);
116 ASSERT(pathlen
== 0);
118 link
[ip
->i_d
.di_size
] = '\0';
127 struct xfs_inode
*ip
,
130 struct xfs_mount
*mp
= ip
->i_mount
;
134 trace_xfs_readlink(ip
);
136 if (XFS_FORCED_SHUTDOWN(mp
))
137 return XFS_ERROR(EIO
);
139 xfs_ilock(ip
, XFS_ILOCK_SHARED
);
141 pathlen
= ip
->i_d
.di_size
;
145 if (pathlen
< 0 || pathlen
> MAXPATHLEN
) {
146 xfs_alert(mp
, "%s: inode (%llu) bad symlink length (%lld)",
147 __func__
, (unsigned long long) ip
->i_ino
,
148 (long long) pathlen
);
150 error
= XFS_ERROR(EFSCORRUPTED
);
155 if (ip
->i_df
.if_flags
& XFS_IFINLINE
) {
156 memcpy(link
, ip
->i_df
.if_u1
.if_data
, pathlen
);
157 link
[pathlen
] = '\0';
159 error
= xfs_readlink_bmap(ip
, link
);
163 xfs_iunlock(ip
, XFS_ILOCK_SHARED
);
169 struct xfs_inode
*dp
,
170 struct xfs_name
*link_name
,
171 const char *target_path
,
173 struct xfs_inode
**ipp
)
175 struct xfs_mount
*mp
= dp
->i_mount
;
176 struct xfs_trans
*tp
= NULL
;
177 struct xfs_inode
*ip
= NULL
;
180 struct xfs_bmap_free free_list
;
181 xfs_fsblock_t first_block
;
182 bool unlock_dp_on_error
= false;
185 xfs_fileoff_t first_fsb
;
186 xfs_filblks_t fs_blocks
;
188 struct xfs_bmbt_irec mval
[XFS_SYMLINK_MAPS
];
190 const char *cur_chunk
;
195 struct xfs_dquot
*udqp
= NULL
;
196 struct xfs_dquot
*gdqp
= NULL
;
197 struct xfs_dquot
*pdqp
= NULL
;
202 trace_xfs_symlink(dp
, link_name
);
204 if (XFS_FORCED_SHUTDOWN(mp
))
205 return XFS_ERROR(EIO
);
208 * Check component lengths of the target path name.
210 pathlen
= strlen(target_path
);
211 if (pathlen
>= MAXPATHLEN
) /* total string too long */
212 return XFS_ERROR(ENAMETOOLONG
);
215 prid
= xfs_get_initial_prid(dp
);
218 * Make sure that we have allocated dquot(s) on disk.
220 error
= xfs_qm_vop_dqalloc(dp
,
221 xfs_kuid_to_uid(current_fsuid()),
222 xfs_kgid_to_gid(current_fsgid()), prid
,
223 XFS_QMOPT_QUOTALL
| XFS_QMOPT_INHERIT
,
224 &udqp
, &gdqp
, &pdqp
);
228 tp
= xfs_trans_alloc(mp
, XFS_TRANS_SYMLINK
);
229 cancel_flags
= XFS_TRANS_RELEASE_LOG_RES
;
231 * The symlink will fit into the inode data fork?
232 * There can't be any attributes so we get the whole variable part.
234 if (pathlen
<= XFS_LITINO(mp
, dp
->i_d
.di_version
))
237 fs_blocks
= xfs_symlink_blocks(mp
, pathlen
);
238 resblks
= XFS_SYMLINK_SPACE_RES(mp
, link_name
->len
, fs_blocks
);
239 error
= xfs_trans_reserve(tp
, &M_RES(mp
)->tr_symlink
, resblks
, 0);
240 if (error
== ENOSPC
&& fs_blocks
== 0) {
242 error
= xfs_trans_reserve(tp
, &M_RES(mp
)->tr_symlink
, 0, 0);
249 xfs_ilock(dp
, XFS_ILOCK_EXCL
| XFS_ILOCK_PARENT
);
250 unlock_dp_on_error
= true;
253 * Check whether the directory allows new symlinks or not.
255 if (dp
->i_d
.di_flags
& XFS_DIFLAG_NOSYMLINKS
) {
256 error
= XFS_ERROR(EPERM
);
261 * Reserve disk quota : blocks and inode.
263 error
= xfs_trans_reserve_quota(tp
, mp
, udqp
, gdqp
,
264 pdqp
, resblks
, 1, 0);
269 * Check for ability to enter directory entry, if no space reserved.
271 error
= xfs_dir_canenter(tp
, dp
, link_name
, resblks
);
275 * Initialize the bmap freelist prior to calling either
276 * bmapi or the directory create code.
278 xfs_bmap_init(&free_list
, &first_block
);
281 * Allocate an inode for the symlink.
283 error
= xfs_dir_ialloc(&tp
, dp
, S_IFLNK
| (mode
& ~S_IFMT
), 1, 0,
284 prid
, resblks
> 0, &ip
, NULL
);
292 * An error after we've joined dp to the transaction will result in the
293 * transaction cancel unlocking dp so don't do it explicitly in the
296 xfs_trans_ijoin(tp
, dp
, XFS_ILOCK_EXCL
);
297 unlock_dp_on_error
= false;
300 * Also attach the dquot(s) to it, if applicable.
302 xfs_qm_vop_create_dqattach(tp
, ip
, udqp
, gdqp
, pdqp
);
305 resblks
-= XFS_IALLOC_SPACE_RES(mp
);
307 * If the symlink will fit into the inode, write it inline.
309 if (pathlen
<= XFS_IFORK_DSIZE(ip
)) {
310 xfs_idata_realloc(ip
, pathlen
, XFS_DATA_FORK
);
311 memcpy(ip
->i_df
.if_u1
.if_data
, target_path
, pathlen
);
312 ip
->i_d
.di_size
= pathlen
;
315 * The inode was initially created in extent format.
317 ip
->i_df
.if_flags
&= ~(XFS_IFEXTENTS
| XFS_IFBROOT
);
318 ip
->i_df
.if_flags
|= XFS_IFINLINE
;
320 ip
->i_d
.di_format
= XFS_DINODE_FMT_LOCAL
;
321 xfs_trans_log_inode(tp
, ip
, XFS_ILOG_DDATA
| XFS_ILOG_CORE
);
327 nmaps
= XFS_SYMLINK_MAPS
;
329 error
= xfs_bmapi_write(tp
, ip
, first_fsb
, fs_blocks
,
330 XFS_BMAPI_METADATA
, &first_block
, resblks
,
331 mval
, &nmaps
, &free_list
);
336 resblks
-= fs_blocks
;
337 ip
->i_d
.di_size
= pathlen
;
338 xfs_trans_log_inode(tp
, ip
, XFS_ILOG_CORE
);
340 cur_chunk
= target_path
;
342 for (n
= 0; n
< nmaps
; n
++) {
345 d
= XFS_FSB_TO_DADDR(mp
, mval
[n
].br_startblock
);
346 byte_cnt
= XFS_FSB_TO_B(mp
, mval
[n
].br_blockcount
);
347 bp
= xfs_trans_get_buf(tp
, mp
->m_ddev_targp
, d
,
353 bp
->b_ops
= &xfs_symlink_buf_ops
;
355 byte_cnt
= XFS_SYMLINK_BUF_SPACE(mp
, byte_cnt
);
356 byte_cnt
= min(byte_cnt
, pathlen
);
359 buf
+= xfs_symlink_hdr_set(mp
, ip
->i_ino
, offset
,
362 memcpy(buf
, cur_chunk
, byte_cnt
);
364 cur_chunk
+= byte_cnt
;
368 xfs_trans_buf_set_type(tp
, bp
, XFS_BLFT_SYMLINK_BUF
);
369 xfs_trans_log_buf(tp
, bp
, 0, (buf
+ byte_cnt
- 1) -
372 ASSERT(pathlen
== 0);
376 * Create the directory entry for the symlink.
378 error
= xfs_dir_createname(tp
, dp
, link_name
, ip
->i_ino
,
379 &first_block
, &free_list
, resblks
);
382 xfs_trans_ichgtime(tp
, dp
, XFS_ICHGTIME_MOD
| XFS_ICHGTIME_CHG
);
383 xfs_trans_log_inode(tp
, dp
, XFS_ILOG_CORE
);
386 * If this is a synchronous mount, make sure that the
387 * symlink transaction goes to disk before returning to
390 if (mp
->m_flags
& (XFS_MOUNT_WSYNC
|XFS_MOUNT_DIRSYNC
)) {
391 xfs_trans_set_sync(tp
);
394 error
= xfs_bmap_finish(&tp
, &free_list
, &committed
);
398 error
= xfs_trans_commit(tp
, XFS_TRANS_RELEASE_LOG_RES
);
409 xfs_bmap_cancel(&free_list
);
410 cancel_flags
|= XFS_TRANS_ABORT
;
412 xfs_trans_cancel(tp
, cancel_flags
);
417 if (unlock_dp_on_error
)
418 xfs_iunlock(dp
, XFS_ILOCK_EXCL
);
424 * Free a symlink that has blocks associated with it.
427 xfs_inactive_symlink_rmt(
428 struct xfs_inode
*ip
)
434 xfs_fsblock_t first_block
;
435 xfs_bmap_free_t free_list
;
438 xfs_bmbt_irec_t mval
[XFS_SYMLINK_MAPS
];
444 ASSERT(ip
->i_df
.if_flags
& XFS_IFEXTENTS
);
446 * We're freeing a symlink that has some
447 * blocks allocated to it. Free the
448 * blocks here. We know that we've got
449 * either 1 or 2 extents and that we can
450 * free them all in one bunmapi call.
452 ASSERT(ip
->i_d
.di_nextents
> 0 && ip
->i_d
.di_nextents
<= 2);
454 tp
= xfs_trans_alloc(mp
, XFS_TRANS_INACTIVE
);
455 error
= xfs_trans_reserve(tp
, &M_RES(mp
)->tr_itruncate
, 0, 0);
457 xfs_trans_cancel(tp
, 0);
461 xfs_ilock(ip
, XFS_ILOCK_EXCL
);
462 xfs_trans_ijoin(tp
, ip
, 0);
465 * Lock the inode, fix the size, and join it to the transaction.
466 * Hold it so in the normal path, we still have it locked for
467 * the second transaction. In the error paths we need it
468 * held so the cancel won't rele it, see below.
470 size
= (int)ip
->i_d
.di_size
;
472 xfs_trans_log_inode(tp
, ip
, XFS_ILOG_CORE
);
474 * Find the block(s) so we can inval and unmap them.
477 xfs_bmap_init(&free_list
, &first_block
);
478 nmaps
= ARRAY_SIZE(mval
);
479 error
= xfs_bmapi_read(ip
, 0, xfs_symlink_blocks(mp
, size
),
482 goto error_trans_cancel
;
484 * Invalidate the block(s). No validation is done.
486 for (i
= 0; i
< nmaps
; i
++) {
487 bp
= xfs_trans_get_buf(tp
, mp
->m_ddev_targp
,
488 XFS_FSB_TO_DADDR(mp
, mval
[i
].br_startblock
),
489 XFS_FSB_TO_BB(mp
, mval
[i
].br_blockcount
), 0);
492 goto error_bmap_cancel
;
494 xfs_trans_binval(tp
, bp
);
497 * Unmap the dead block(s) to the free_list.
499 error
= xfs_bunmapi(tp
, ip
, 0, size
, XFS_BMAPI_METADATA
, nmaps
,
500 &first_block
, &free_list
, &done
);
502 goto error_bmap_cancel
;
505 * Commit the first transaction. This logs the EFI and the inode.
507 error
= xfs_bmap_finish(&tp
, &free_list
, &committed
);
509 goto error_bmap_cancel
;
511 * The transaction must have been committed, since there were
512 * actually extents freed by xfs_bunmapi. See xfs_bmap_finish.
513 * The new tp has the extent freeing and EFDs.
517 * The first xact was committed, so add the inode to the new one.
518 * Mark it dirty so it will be logged and moved forward in the log as
519 * part of every commit.
521 xfs_trans_ijoin(tp
, ip
, 0);
522 xfs_trans_log_inode(tp
, ip
, XFS_ILOG_CORE
);
524 * Commit the transaction containing extent freeing and EFDs.
526 error
= xfs_trans_commit(tp
, XFS_TRANS_RELEASE_LOG_RES
);
528 ASSERT(XFS_FORCED_SHUTDOWN(mp
));
533 * Remove the memory for extent descriptions (just bookkeeping).
535 if (ip
->i_df
.if_bytes
)
536 xfs_idata_realloc(ip
, -ip
->i_df
.if_bytes
, XFS_DATA_FORK
);
537 ASSERT(ip
->i_df
.if_bytes
== 0);
539 xfs_iunlock(ip
, XFS_ILOCK_EXCL
);
543 xfs_bmap_cancel(&free_list
);
545 xfs_trans_cancel(tp
, XFS_TRANS_RELEASE_LOG_RES
| XFS_TRANS_ABORT
);
547 xfs_iunlock(ip
, XFS_ILOCK_EXCL
);
552 * xfs_inactive_symlink - free a symlink
555 xfs_inactive_symlink(
556 struct xfs_inode
*ip
)
558 struct xfs_mount
*mp
= ip
->i_mount
;
561 trace_xfs_inactive_symlink(ip
);
563 if (XFS_FORCED_SHUTDOWN(mp
))
564 return XFS_ERROR(EIO
);
566 xfs_ilock(ip
, XFS_ILOCK_EXCL
);
569 * Zero length symlinks _can_ exist.
571 pathlen
= (int)ip
->i_d
.di_size
;
573 xfs_iunlock(ip
, XFS_ILOCK_EXCL
);
577 if (pathlen
< 0 || pathlen
> MAXPATHLEN
) {
578 xfs_alert(mp
, "%s: inode (0x%llx) bad symlink length (%d)",
579 __func__
, (unsigned long long)ip
->i_ino
, pathlen
);
580 xfs_iunlock(ip
, XFS_ILOCK_EXCL
);
582 return XFS_ERROR(EFSCORRUPTED
);
585 if (ip
->i_df
.if_flags
& XFS_IFINLINE
) {
586 if (ip
->i_df
.if_bytes
> 0)
587 xfs_idata_realloc(ip
, -(ip
->i_df
.if_bytes
),
589 xfs_iunlock(ip
, XFS_ILOCK_EXCL
);
590 ASSERT(ip
->i_df
.if_bytes
== 0);
594 xfs_iunlock(ip
, XFS_ILOCK_EXCL
);
596 /* remove the remote symlink */
597 return xfs_inactive_symlink_rmt(ip
);