1/*
2 * Copyright (c) 2000-2006 Silicon Graphics, Inc.
3 * Copyright (c) 2013 Red Hat, Inc.
4 * All Rights Reserved.
5 *
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.
9 *
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.
14 *
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
18 */
19#include "xfs.h"
20#include "xfs_fs.h"
21#include "xfs_shared.h"
22#include "xfs_format.h"
23#include "xfs_log_format.h"
24#include "xfs_trans_resv.h"
25#include "xfs_mount.h"
26#include "xfs_inode.h"
27#include "xfs_quota.h"
28#include "xfs_trans.h"
29#include "xfs_qm.h"
30#include "xfs_error.h"
31#include "xfs_cksum.h"
32#include "xfs_trace.h"
33
34int
35xfs_calc_dquots_per_chunk(
36	unsigned int		nbblks)	/* basic block units */
37{
38	unsigned int	ndquots;
39
40	ASSERT(nbblks > 0);
41	ndquots = BBTOB(nbblks);
42	do_div(ndquots, sizeof(xfs_dqblk_t));
43
44	return ndquots;
45}
46
47/*
48 * Do some primitive error checking on ondisk dquot data structures.
49 */
50int
51xfs_dqcheck(
52	struct xfs_mount *mp,
53	xfs_disk_dquot_t *ddq,
54	xfs_dqid_t	 id,
55	uint		 type,	  /* used only when IO_dorepair is true */
56	uint		 flags,
57	const char	 *str)
58{
59	xfs_dqblk_t	 *d = (xfs_dqblk_t *)ddq;
60	int		errs = 0;
61
62	/*
63	 * We can encounter an uninitialized dquot buffer for 2 reasons:
64	 * 1. If we crash while deleting the quotainode(s), and those blks got
65	 *    used for user data. This is because we take the path of regular
66	 *    file deletion; however, the size field of quotainodes is never
67	 *    updated, so all the tricks that we play in itruncate_finish
68	 *    don't quite matter.
69	 *
70	 * 2. We don't play the quota buffers when there's a quotaoff logitem.
71	 *    But the allocation will be replayed so we'll end up with an
72	 *    uninitialized quota block.
73	 *
74	 * This is all fine; things are still consistent, and we haven't lost
75	 * any quota information. Just don't complain about bad dquot blks.
76	 */
77	if (ddq->d_magic != cpu_to_be16(XFS_DQUOT_MAGIC)) {
78		if (flags & XFS_QMOPT_DOWARN)
79			xfs_alert(mp,
80			"%s : XFS dquot ID 0x%x, magic 0x%x != 0x%x",
81			str, id, be16_to_cpu(ddq->d_magic), XFS_DQUOT_MAGIC);
82		errs++;
83	}
84	if (ddq->d_version != XFS_DQUOT_VERSION) {
85		if (flags & XFS_QMOPT_DOWARN)
86			xfs_alert(mp,
87			"%s : XFS dquot ID 0x%x, version 0x%x != 0x%x",
88			str, id, ddq->d_version, XFS_DQUOT_VERSION);
89		errs++;
90	}
91
92	if (ddq->d_flags != XFS_DQ_USER &&
93	    ddq->d_flags != XFS_DQ_PROJ &&
94	    ddq->d_flags != XFS_DQ_GROUP) {
95		if (flags & XFS_QMOPT_DOWARN)
96			xfs_alert(mp,
97			"%s : XFS dquot ID 0x%x, unknown flags 0x%x",
98			str, id, ddq->d_flags);
99		errs++;
100	}
101
102	if (id != -1 && id != be32_to_cpu(ddq->d_id)) {
103		if (flags & XFS_QMOPT_DOWARN)
104			xfs_alert(mp,
105			"%s : ondisk-dquot 0x%p, ID mismatch: "
106			"0x%x expected, found id 0x%x",
107			str, ddq, id, be32_to_cpu(ddq->d_id));
108		errs++;
109	}
110
111	if (!errs && ddq->d_id) {
112		if (ddq->d_blk_softlimit &&
113		    be64_to_cpu(ddq->d_bcount) >
114				be64_to_cpu(ddq->d_blk_softlimit)) {
115			if (!ddq->d_btimer) {
116				if (flags & XFS_QMOPT_DOWARN)
117					xfs_alert(mp,
118			"%s : Dquot ID 0x%x (0x%p) BLK TIMER NOT STARTED",
119					str, (int)be32_to_cpu(ddq->d_id), ddq);
120				errs++;
121			}
122		}
123		if (ddq->d_ino_softlimit &&
124		    be64_to_cpu(ddq->d_icount) >
125				be64_to_cpu(ddq->d_ino_softlimit)) {
126			if (!ddq->d_itimer) {
127				if (flags & XFS_QMOPT_DOWARN)
128					xfs_alert(mp,
129			"%s : Dquot ID 0x%x (0x%p) INODE TIMER NOT STARTED",
130					str, (int)be32_to_cpu(ddq->d_id), ddq);
131				errs++;
132			}
133		}
134		if (ddq->d_rtb_softlimit &&
135		    be64_to_cpu(ddq->d_rtbcount) >
136				be64_to_cpu(ddq->d_rtb_softlimit)) {
137			if (!ddq->d_rtbtimer) {
138				if (flags & XFS_QMOPT_DOWARN)
139					xfs_alert(mp,
140			"%s : Dquot ID 0x%x (0x%p) RTBLK TIMER NOT STARTED",
141					str, (int)be32_to_cpu(ddq->d_id), ddq);
142				errs++;
143			}
144		}
145	}
146
147	if (!errs || !(flags & XFS_QMOPT_DQREPAIR))
148		return errs;
149
150	if (flags & XFS_QMOPT_DOWARN)
151		xfs_notice(mp, "Re-initializing dquot ID 0x%x", id);
152
153	/*
154	 * Typically, a repair is only requested by quotacheck.
155	 */
156	ASSERT(id != -1);
157	ASSERT(flags & XFS_QMOPT_DQREPAIR);
158	memset(d, 0, sizeof(xfs_dqblk_t));
159
160	d->dd_diskdq.d_magic = cpu_to_be16(XFS_DQUOT_MAGIC);
161	d->dd_diskdq.d_version = XFS_DQUOT_VERSION;
162	d->dd_diskdq.d_flags = type;
163	d->dd_diskdq.d_id = cpu_to_be32(id);
164
165	if (xfs_sb_version_hascrc(&mp->m_sb)) {
166		uuid_copy(&d->dd_uuid, &mp->m_sb.sb_uuid);
167		xfs_update_cksum((char *)d, sizeof(struct xfs_dqblk),
168				 XFS_DQUOT_CRC_OFF);
169	}
170
171	return errs;
172}
173
174STATIC bool
175xfs_dquot_buf_verify_crc(
176	struct xfs_mount	*mp,
177	struct xfs_buf		*bp)
178{
179	struct xfs_dqblk	*d = (struct xfs_dqblk *)bp->b_addr;
180	int			ndquots;
181	int			i;
182
183	if (!xfs_sb_version_hascrc(&mp->m_sb))
184		return true;
185
186	/*
187	 * if we are in log recovery, the quota subsystem has not been
188	 * initialised so we have no quotainfo structure. In that case, we need
189	 * to manually calculate the number of dquots in the buffer.
190	 */
191	if (mp->m_quotainfo)
192		ndquots = mp->m_quotainfo->qi_dqperchunk;
193	else
194		ndquots = xfs_calc_dquots_per_chunk(
195					XFS_BB_TO_FSB(mp, bp->b_length));
196
197	for (i = 0; i < ndquots; i++, d++) {
198		if (!xfs_verify_cksum((char *)d, sizeof(struct xfs_dqblk),
199				 XFS_DQUOT_CRC_OFF))
200			return false;
201		if (!uuid_equal(&d->dd_uuid, &mp->m_sb.sb_uuid))
202			return false;
203	}
204	return true;
205}
206
207STATIC bool
208xfs_dquot_buf_verify(
209	struct xfs_mount	*mp,
210	struct xfs_buf		*bp,
211	int			warn)
212{
213	struct xfs_dqblk	*d = (struct xfs_dqblk *)bp->b_addr;
214	xfs_dqid_t		id = 0;
215	int			ndquots;
216	int			i;
217
218	/*
219	 * if we are in log recovery, the quota subsystem has not been
220	 * initialised so we have no quotainfo structure. In that case, we need
221	 * to manually calculate the number of dquots in the buffer.
222	 */
223	if (mp->m_quotainfo)
224		ndquots = mp->m_quotainfo->qi_dqperchunk;
225	else
226		ndquots = xfs_calc_dquots_per_chunk(bp->b_length);
227
228	/*
229	 * On the first read of the buffer, verify that each dquot is valid.
230	 * We don't know what the id of the dquot is supposed to be, just that
231	 * they should be increasing monotonically within the buffer. If the
232	 * first id is corrupt, then it will fail on the second dquot in the
233	 * buffer so corruptions could point to the wrong dquot in this case.
234	 */
235	for (i = 0; i < ndquots; i++) {
236		struct xfs_disk_dquot	*ddq;
237		int			error;
238
239		ddq = &d[i].dd_diskdq;
240
241		if (i == 0)
242			id = be32_to_cpu(ddq->d_id);
243
244		error = xfs_dqcheck(mp, ddq, id + i, 0, warn, __func__);
245		if (error)
246			return false;
247	}
248	return true;
249}
250
251static void
252xfs_dquot_buf_read_verify(
253	struct xfs_buf	*bp)
254{
255	struct xfs_mount	*mp = bp->b_target->bt_mount;
256
257	if (!xfs_dquot_buf_verify_crc(mp, bp))
258		xfs_buf_ioerror(bp, -EFSBADCRC);
259	else if (!xfs_dquot_buf_verify(mp, bp, XFS_QMOPT_DOWARN))
260		xfs_buf_ioerror(bp, -EFSCORRUPTED);
261
262	if (bp->b_error)
263		xfs_verifier_error(bp);
264}
265
266/*
267 * readahead errors are silent and simply leave the buffer as !done so a real
268 * read will then be run with the xfs_dquot_buf_ops verifier. See
269 * xfs_inode_buf_verify() for why we use EIO and ~XBF_DONE here rather than
270 * reporting the failure.
271 */
272static void
273xfs_dquot_buf_readahead_verify(
274	struct xfs_buf	*bp)
275{
276	struct xfs_mount	*mp = bp->b_target->bt_mount;
277
278	if (!xfs_dquot_buf_verify_crc(mp, bp) ||
279	    !xfs_dquot_buf_verify(mp, bp, 0)) {
280		xfs_buf_ioerror(bp, -EIO);
281		bp->b_flags &= ~XBF_DONE;
282	}
283}
284
285/*
286 * we don't calculate the CRC here as that is done when the dquot is flushed to
287 * the buffer after the update is done. This ensures that the dquot in the
288 * buffer always has an up-to-date CRC value.
289 */
290static void
291xfs_dquot_buf_write_verify(
292	struct xfs_buf	*bp)
293{
294	struct xfs_mount	*mp = bp->b_target->bt_mount;
295
296	if (!xfs_dquot_buf_verify(mp, bp, XFS_QMOPT_DOWARN)) {
297		xfs_buf_ioerror(bp, -EFSCORRUPTED);
298		xfs_verifier_error(bp);
299		return;
300	}
301}
302
303const struct xfs_buf_ops xfs_dquot_buf_ops = {
304	.verify_read = xfs_dquot_buf_read_verify,
305	.verify_write = xfs_dquot_buf_write_verify,
306};
307
308const struct xfs_buf_ops xfs_dquot_buf_ra_ops = {
309	.verify_read = xfs_dquot_buf_readahead_verify,
310	.verify_write = xfs_dquot_buf_write_verify,
311};
312