summaryrefslogtreecommitdiff
path: root/fs/xfs/xfs_dfrag.c
blob: 39c4480bbb9ff61409c7b43bbd7b487dbc0822b8 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
/*
 * Copyright (c) 2000-2006 Silicon Graphics, Inc.
 * All Rights Reserved.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it would be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write the Free Software Foundation,
 * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */
#include "xfs.h"
#include "xfs_fs.h"
#include "xfs_types.h"
#include "xfs_bit.h"
#include "xfs_log.h"
#include "xfs_inum.h"
#include "xfs_trans.h"
#include "xfs_sb.h"
#include "xfs_ag.h"
#include "xfs_dir2.h"
#include "xfs_dmapi.h"
#include "xfs_mount.h"
#include "xfs_bmap_btree.h"
#include "xfs_alloc_btree.h"
#include "xfs_ialloc_btree.h"
#include "xfs_dir2_sf.h"
#include "xfs_attr_sf.h"
#include "xfs_dinode.h"
#include "xfs_inode.h"
#include "xfs_inode_item.h"
#include "xfs_bmap.h"
#include "xfs_btree.h"
#include "xfs_ialloc.h"
#include "xfs_itable.h"
#include "xfs_dfrag.h"
#include "xfs_error.h"
#include "xfs_rw.h"
#include "xfs_vnodeops.h"

/*
 * Syssgi interface for swapext
 */
int
xfs_swapext(
	xfs_swapext_t	__user *sxu)
{
	xfs_swapext_t	*sxp;
	xfs_inode_t     *ip=NULL, *tip=NULL;
	xfs_mount_t     *mp;
	struct file	*fp = NULL, *tfp = NULL;
	bhv_vnode_t	*vp, *tvp;
	int		error = 0;

	sxp = kmem_alloc(sizeof(xfs_swapext_t), KM_MAYFAIL);
	if (!sxp) {
		error = XFS_ERROR(ENOMEM);
		goto error0;
	}

	if (copy_from_user(sxp, sxu, sizeof(xfs_swapext_t))) {
		error = XFS_ERROR(EFAULT);
		goto error0;
	}

	/* Pull information for the target fd */
	if (((fp = fget((int)sxp->sx_fdtarget)) == NULL) ||
	    ((vp = vn_from_inode(fp->f_path.dentry->d_inode)) == NULL))  {
		error = XFS_ERROR(EINVAL);
		goto error0;
	}

	ip = xfs_vtoi(vp);
	if (ip == NULL) {
		error = XFS_ERROR(EBADF);
		goto error0;
	}

	if (((tfp = fget((int)sxp->sx_fdtmp)) == NULL) ||
	    ((tvp = vn_from_inode(tfp->f_path.dentry->d_inode)) == NULL)) {
		error = XFS_ERROR(EINVAL);
		goto error0;
	}

	tip = xfs_vtoi(tvp);
	if (tip == NULL) {
		error = XFS_ERROR(EBADF);
		goto error0;
	}

	if (ip->i_mount != tip->i_mount) {
		error =  XFS_ERROR(EINVAL);
		goto error0;
	}

	if (ip->i_ino == tip->i_ino) {
		error =  XFS_ERROR(EINVAL);
		goto error0;
	}

	mp = ip->i_mount;

	if (XFS_FORCED_SHUTDOWN(mp)) {
		error =  XFS_ERROR(EIO);
		goto error0;
	}

	error = xfs_swap_extents(ip, tip, sxp);

 error0:
	if (fp != NULL)
		fput(fp);
	if (tfp != NULL)
		fput(tfp);

	if (sxp != NULL)
		kmem_free(sxp, sizeof(xfs_swapext_t));

	return error;
}

int
xfs_swap_extents(
	xfs_inode_t	*ip,
	xfs_inode_t	*tip,
	xfs_swapext_t	*sxp)
{
	xfs_mount_t	*mp;
	xfs_inode_t	*ips[2];
	xfs_trans_t	*tp;
	xfs_bstat_t	*sbp = &sxp->sx_stat;
	bhv_vnode_t	*vp, *tvp;
	xfs_ifork_t	*tempifp, *ifp, *tifp;
	int		ilf_fields, tilf_fields;
	static uint	lock_flags = XFS_ILOCK_EXCL | XFS_IOLOCK_EXCL;
	int		error = 0;
	int		aforkblks = 0;
	int		taforkblks = 0;
	__uint64_t	tmp;
	char		locked = 0;

	mp = ip->i_mount;

	tempifp = kmem_alloc(sizeof(xfs_ifork_t), KM_MAYFAIL);
	if (!tempifp) {
		error = XFS_ERROR(ENOMEM);
		goto error0;
	}

	sbp = &sxp->sx_stat;
	vp = XFS_ITOV(ip);
	tvp = XFS_ITOV(tip);

	/* Lock in i_ino order */
	if (ip->i_ino < tip->i_ino) {
		ips[0] = ip;
		ips[1] = tip;
	} else {
		ips[0] = tip;
		ips[1] = ip;
	}

	xfs_lock_inodes(ips, 2, 0, lock_flags);
	locked = 1;

	/* Check permissions */
	error = xfs_iaccess(ip, S_IWUSR, NULL);
	if (error)
		goto error0;

	error = xfs_iaccess(tip, S_IWUSR, NULL);
	if (error)
		goto error0;

	/* Verify that both files have the same format */
	if ((ip->i_d.di_mode & S_IFMT) != (tip->i_d.di_mode & S_IFMT)) {
		error = XFS_ERROR(EINVAL);
		goto error0;
	}

	/* Verify both files are either real-time or non-realtime */
	if ((ip->i_d.di_flags & XFS_DIFLAG_REALTIME) !=
	    (tip->i_d.di_flags & XFS_DIFLAG_REALTIME)) {
		error = XFS_ERROR(EINVAL);
		goto error0;
	}

	/* Should never get a local format */
	if (ip->i_d.di_format == XFS_DINODE_FMT_LOCAL ||
	    tip->i_d.di_format == XFS_DINODE_FMT_LOCAL) {
		error = XFS_ERROR(EINVAL);
		goto error0;
	}

	if (VN_CACHED(tvp) != 0) {
		xfs_inval_cached_trace(&tip->i_iocore, 0, -1, 0, -1);
		error = xfs_flushinval_pages(tip, 0, -1,
				FI_REMAPF_LOCKED);
		if (error)
			goto error0;
	}

	/* Verify O_DIRECT for ftmp */
	if (VN_CACHED(tvp) != 0) {
		error = XFS_ERROR(EINVAL);
		goto error0;
	}

	/* Verify all data are being swapped */
	if (sxp->sx_offset != 0 ||
	    sxp->sx_length != ip->i_d.di_size ||
	    sxp->sx_length != tip->i_d.di_size) {
		error = XFS_ERROR(EFAULT);
		goto error0;
	}

	/*
	 * If the target has extended attributes, the tmp file
	 * must also in order to ensure the correct data fork
	 * format.
	 */
	if ( XFS_IFORK_Q(ip) != XFS_IFORK_Q(tip) ) {
		error = XFS_ERROR(EINVAL);
		goto error0;
	}

	/*
	 * Compare the current change & modify times with that
	 * passed in.  If they differ, we abort this swap.
	 * This is the mechanism used to ensure the calling
	 * process that the file was not changed out from
	 * under it.
	 */
	if ((sbp->bs_ctime.tv_sec != ip->i_d.di_ctime.t_sec) ||
	    (sbp->bs_ctime.tv_nsec != ip->i_d.di_ctime.t_nsec) ||
	    (sbp->bs_mtime.tv_sec != ip->i_d.di_mtime.t_sec) ||
	    (sbp->bs_mtime.tv_nsec != ip->i_d.di_mtime.t_nsec)) {
		error = XFS_ERROR(EBUSY);
		goto error0;
	}

	/* We need to fail if the file is memory mapped.  Once we have tossed
	 * all existing pages, the page fault will have no option
	 * but to go to the filesystem for pages. By making the page fault call
	 * vop_read (or write in the case of autogrow) they block on the iolock
	 * until we have switched the extents.
	 */
	if (VN_MAPPED(vp)) {
		error = XFS_ERROR(EBUSY);
		goto error0;
	}

	xfs_iunlock(ip, XFS_ILOCK_EXCL);
	xfs_iunlock(tip, XFS_ILOCK_EXCL);

	/*
	 * There is a race condition here since we gave up the
	 * ilock.  However, the data fork will not change since
	 * we have the iolock (locked for truncation too) so we
	 * are safe.  We don't really care if non-io related
	 * fields change.
	 */

	xfs_tosspages(ip, 0, -1, FI_REMAPF);

	tp = xfs_trans_alloc(mp, XFS_TRANS_SWAPEXT);
	if ((error = xfs_trans_reserve(tp, 0,
				     XFS_ICHANGE_LOG_RES(mp), 0,
				     0, 0))) {
		xfs_iunlock(ip,  XFS_IOLOCK_EXCL);
		xfs_iunlock(tip, XFS_IOLOCK_EXCL);
		xfs_trans_cancel(tp, 0);
		locked = 0;
		goto error0;
	}
	xfs_lock_inodes(ips, 2, 0, XFS_ILOCK_EXCL);

	/*
	 * Count the number of extended attribute blocks
	 */
	if ( ((XFS_IFORK_Q(ip) != 0) && (ip->i_d.di_anextents > 0)) &&
	     (ip->i_d.di_aformat != XFS_DINODE_FMT_LOCAL)) {
		error = xfs_bmap_count_blocks(tp, ip, XFS_ATTR_FORK, &aforkblks);
		if (error) {
			xfs_trans_cancel(tp, 0);
			goto error0;
		}
	}
	if ( ((XFS_IFORK_Q(tip) != 0) && (tip->i_d.di_anextents > 0)) &&
	     (tip->i_d.di_aformat != XFS_DINODE_FMT_LOCAL)) {
		error = xfs_bmap_count_blocks(tp, tip, XFS_ATTR_FORK,
			&taforkblks);
		if (error) {
			xfs_trans_cancel(tp, 0);
			goto error0;
		}
	}

	/*
	 * Swap the data forks of the inodes
	 */
	ifp = &ip->i_df;
	tifp = &tip->i_df;
	*tempifp = *ifp;	/* struct copy */
	*ifp = *tifp;		/* struct copy */
	*tifp = *tempifp;	/* struct copy */

	/*
	 * Fix the on-disk inode values
	 */
	tmp = (__uint64_t)ip->i_d.di_nblocks;
	ip->i_d.di_nblocks = tip->i_d.di_nblocks - taforkblks + aforkblks;
	tip->i_d.di_nblocks = tmp + taforkblks - aforkblks;

	tmp = (__uint64_t) ip->i_d.di_nextents;
	ip->i_d.di_nextents = tip->i_d.di_nextents;
	tip->i_d.di_nextents = tmp;

	tmp = (__uint64_t) ip->i_d.di_format;
	ip->i_d.di_format = tip->i_d.di_format;
	tip->i_d.di_format = tmp;

	ilf_fields = XFS_ILOG_CORE;

	switch(ip->i_d.di_format) {
	case XFS_DINODE_FMT_EXTENTS:
		/* If the extents fit in the inode, fix the
		 * pointer.  Otherwise it's already NULL or
		 * pointing to the extent.
		 */
		if (ip->i_d.di_nextents <= XFS_INLINE_EXTS) {
			ifp->if_u1.if_extents =
				ifp->if_u2.if_inline_ext;
		}
		ilf_fields |= XFS_ILOG_DEXT;
		break;
	case XFS_DINODE_FMT_BTREE:
		ilf_fields |= XFS_ILOG_DBROOT;
		break;
	}

	tilf_fields = XFS_ILOG_CORE;

	switch(tip->i_d.di_format) {
	case XFS_DINODE_FMT_EXTENTS:
		/* If the extents fit in the inode, fix the
		 * pointer.  Otherwise it's already NULL or
		 * pointing to the extent.
		 */
		if (tip->i_d.di_nextents <= XFS_INLINE_EXTS) {
			tifp->if_u1.if_extents =
				tifp->if_u2.if_inline_ext;
		}
		tilf_fields |= XFS_ILOG_DEXT;
		break;
	case XFS_DINODE_FMT_BTREE:
		tilf_fields |= XFS_ILOG_DBROOT;
		break;
	}

	/*
	 * Increment vnode ref counts since xfs_trans_commit &
	 * xfs_trans_cancel will both unlock the inodes and
	 * decrement the associated ref counts.
	 */
	VN_HOLD(vp);
	VN_HOLD(tvp);

	xfs_trans_ijoin(tp, ip, lock_flags);
	xfs_trans_ijoin(tp, tip, lock_flags);

	xfs_trans_log_inode(tp, ip,  ilf_fields);
	xfs_trans_log_inode(tp, tip, tilf_fields);

	/*
	 * If this is a synchronous mount, make sure that the
	 * transaction goes to disk before returning to the user.
	 */
	if (mp->m_flags & XFS_MOUNT_WSYNC) {
		xfs_trans_set_sync(tp);
	}

	error = xfs_trans_commit(tp, XFS_TRANS_SWAPEXT);
	locked = 0;

 error0:
	if (locked) {
		xfs_iunlock(ip,  lock_flags);
		xfs_iunlock(tip, lock_flags);
	}
	if (tempifp != NULL)
		kmem_free(tempifp, sizeof(xfs_ifork_t));
	return error;
}