xref: /openbmc/linux/fs/xfs/libxfs/xfs_dquot_buf.c (revision fff74a93)
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_sb.h"
26 #include "xfs_ag.h"
27 #include "xfs_mount.h"
28 #include "xfs_inode.h"
29 #include "xfs_quota.h"
30 #include "xfs_trans.h"
31 #include "xfs_qm.h"
32 #include "xfs_error.h"
33 #include "xfs_cksum.h"
34 #include "xfs_trace.h"
35 
36 int
37 xfs_calc_dquots_per_chunk(
38 	unsigned int		nbblks)	/* basic block units */
39 {
40 	unsigned int	ndquots;
41 
42 	ASSERT(nbblks > 0);
43 	ndquots = BBTOB(nbblks);
44 	do_div(ndquots, sizeof(xfs_dqblk_t));
45 
46 	return ndquots;
47 }
48 
49 /*
50  * Do some primitive error checking on ondisk dquot data structures.
51  */
52 int
53 xfs_dqcheck(
54 	struct xfs_mount *mp,
55 	xfs_disk_dquot_t *ddq,
56 	xfs_dqid_t	 id,
57 	uint		 type,	  /* used only when IO_dorepair is true */
58 	uint		 flags,
59 	char		 *str)
60 {
61 	xfs_dqblk_t	 *d = (xfs_dqblk_t *)ddq;
62 	int		errs = 0;
63 
64 	/*
65 	 * We can encounter an uninitialized dquot buffer for 2 reasons:
66 	 * 1. If we crash while deleting the quotainode(s), and those blks got
67 	 *    used for user data. This is because we take the path of regular
68 	 *    file deletion; however, the size field of quotainodes is never
69 	 *    updated, so all the tricks that we play in itruncate_finish
70 	 *    don't quite matter.
71 	 *
72 	 * 2. We don't play the quota buffers when there's a quotaoff logitem.
73 	 *    But the allocation will be replayed so we'll end up with an
74 	 *    uninitialized quota block.
75 	 *
76 	 * This is all fine; things are still consistent, and we haven't lost
77 	 * any quota information. Just don't complain about bad dquot blks.
78 	 */
79 	if (ddq->d_magic != cpu_to_be16(XFS_DQUOT_MAGIC)) {
80 		if (flags & XFS_QMOPT_DOWARN)
81 			xfs_alert(mp,
82 			"%s : XFS dquot ID 0x%x, magic 0x%x != 0x%x",
83 			str, id, be16_to_cpu(ddq->d_magic), XFS_DQUOT_MAGIC);
84 		errs++;
85 	}
86 	if (ddq->d_version != XFS_DQUOT_VERSION) {
87 		if (flags & XFS_QMOPT_DOWARN)
88 			xfs_alert(mp,
89 			"%s : XFS dquot ID 0x%x, version 0x%x != 0x%x",
90 			str, id, ddq->d_version, XFS_DQUOT_VERSION);
91 		errs++;
92 	}
93 
94 	if (ddq->d_flags != XFS_DQ_USER &&
95 	    ddq->d_flags != XFS_DQ_PROJ &&
96 	    ddq->d_flags != XFS_DQ_GROUP) {
97 		if (flags & XFS_QMOPT_DOWARN)
98 			xfs_alert(mp,
99 			"%s : XFS dquot ID 0x%x, unknown flags 0x%x",
100 			str, id, ddq->d_flags);
101 		errs++;
102 	}
103 
104 	if (id != -1 && id != be32_to_cpu(ddq->d_id)) {
105 		if (flags & XFS_QMOPT_DOWARN)
106 			xfs_alert(mp,
107 			"%s : ondisk-dquot 0x%p, ID mismatch: "
108 			"0x%x expected, found id 0x%x",
109 			str, ddq, id, be32_to_cpu(ddq->d_id));
110 		errs++;
111 	}
112 
113 	if (!errs && ddq->d_id) {
114 		if (ddq->d_blk_softlimit &&
115 		    be64_to_cpu(ddq->d_bcount) >
116 				be64_to_cpu(ddq->d_blk_softlimit)) {
117 			if (!ddq->d_btimer) {
118 				if (flags & XFS_QMOPT_DOWARN)
119 					xfs_alert(mp,
120 			"%s : Dquot ID 0x%x (0x%p) BLK TIMER NOT STARTED",
121 					str, (int)be32_to_cpu(ddq->d_id), ddq);
122 				errs++;
123 			}
124 		}
125 		if (ddq->d_ino_softlimit &&
126 		    be64_to_cpu(ddq->d_icount) >
127 				be64_to_cpu(ddq->d_ino_softlimit)) {
128 			if (!ddq->d_itimer) {
129 				if (flags & XFS_QMOPT_DOWARN)
130 					xfs_alert(mp,
131 			"%s : Dquot ID 0x%x (0x%p) INODE TIMER NOT STARTED",
132 					str, (int)be32_to_cpu(ddq->d_id), ddq);
133 				errs++;
134 			}
135 		}
136 		if (ddq->d_rtb_softlimit &&
137 		    be64_to_cpu(ddq->d_rtbcount) >
138 				be64_to_cpu(ddq->d_rtb_softlimit)) {
139 			if (!ddq->d_rtbtimer) {
140 				if (flags & XFS_QMOPT_DOWARN)
141 					xfs_alert(mp,
142 			"%s : Dquot ID 0x%x (0x%p) RTBLK TIMER NOT STARTED",
143 					str, (int)be32_to_cpu(ddq->d_id), ddq);
144 				errs++;
145 			}
146 		}
147 	}
148 
149 	if (!errs || !(flags & XFS_QMOPT_DQREPAIR))
150 		return errs;
151 
152 	if (flags & XFS_QMOPT_DOWARN)
153 		xfs_notice(mp, "Re-initializing dquot ID 0x%x", id);
154 
155 	/*
156 	 * Typically, a repair is only requested by quotacheck.
157 	 */
158 	ASSERT(id != -1);
159 	ASSERT(flags & XFS_QMOPT_DQREPAIR);
160 	memset(d, 0, sizeof(xfs_dqblk_t));
161 
162 	d->dd_diskdq.d_magic = cpu_to_be16(XFS_DQUOT_MAGIC);
163 	d->dd_diskdq.d_version = XFS_DQUOT_VERSION;
164 	d->dd_diskdq.d_flags = type;
165 	d->dd_diskdq.d_id = cpu_to_be32(id);
166 
167 	if (xfs_sb_version_hascrc(&mp->m_sb)) {
168 		uuid_copy(&d->dd_uuid, &mp->m_sb.sb_uuid);
169 		xfs_update_cksum((char *)d, sizeof(struct xfs_dqblk),
170 				 XFS_DQUOT_CRC_OFF);
171 	}
172 
173 	return errs;
174 }
175 
176 STATIC bool
177 xfs_dquot_buf_verify_crc(
178 	struct xfs_mount	*mp,
179 	struct xfs_buf		*bp)
180 {
181 	struct xfs_dqblk	*d = (struct xfs_dqblk *)bp->b_addr;
182 	int			ndquots;
183 	int			i;
184 
185 	if (!xfs_sb_version_hascrc(&mp->m_sb))
186 		return true;
187 
188 	/*
189 	 * if we are in log recovery, the quota subsystem has not been
190 	 * initialised so we have no quotainfo structure. In that case, we need
191 	 * to manually calculate the number of dquots in the buffer.
192 	 */
193 	if (mp->m_quotainfo)
194 		ndquots = mp->m_quotainfo->qi_dqperchunk;
195 	else
196 		ndquots = xfs_calc_dquots_per_chunk(
197 					XFS_BB_TO_FSB(mp, bp->b_length));
198 
199 	for (i = 0; i < ndquots; i++, d++) {
200 		if (!xfs_verify_cksum((char *)d, sizeof(struct xfs_dqblk),
201 				 XFS_DQUOT_CRC_OFF))
202 			return false;
203 		if (!uuid_equal(&d->dd_uuid, &mp->m_sb.sb_uuid))
204 			return false;
205 	}
206 	return true;
207 }
208 
209 STATIC bool
210 xfs_dquot_buf_verify(
211 	struct xfs_mount	*mp,
212 	struct xfs_buf		*bp)
213 {
214 	struct xfs_dqblk	*d = (struct xfs_dqblk *)bp->b_addr;
215 	xfs_dqid_t		id = 0;
216 	int			ndquots;
217 	int			i;
218 
219 	/*
220 	 * if we are in log recovery, the quota subsystem has not been
221 	 * initialised so we have no quotainfo structure. In that case, we need
222 	 * to manually calculate the number of dquots in the buffer.
223 	 */
224 	if (mp->m_quotainfo)
225 		ndquots = mp->m_quotainfo->qi_dqperchunk;
226 	else
227 		ndquots = xfs_calc_dquots_per_chunk(bp->b_length);
228 
229 	/*
230 	 * On the first read of the buffer, verify that each dquot is valid.
231 	 * We don't know what the id of the dquot is supposed to be, just that
232 	 * they should be increasing monotonically within the buffer. If the
233 	 * first id is corrupt, then it will fail on the second dquot in the
234 	 * buffer so corruptions could point to the wrong dquot in this case.
235 	 */
236 	for (i = 0; i < ndquots; i++) {
237 		struct xfs_disk_dquot	*ddq;
238 		int			error;
239 
240 		ddq = &d[i].dd_diskdq;
241 
242 		if (i == 0)
243 			id = be32_to_cpu(ddq->d_id);
244 
245 		error = xfs_dqcheck(mp, ddq, id + i, 0, XFS_QMOPT_DOWARN,
246 				       "xfs_dquot_buf_verify");
247 		if (error)
248 			return false;
249 	}
250 	return true;
251 }
252 
253 static void
254 xfs_dquot_buf_read_verify(
255 	struct xfs_buf	*bp)
256 {
257 	struct xfs_mount	*mp = bp->b_target->bt_mount;
258 
259 	if (!xfs_dquot_buf_verify_crc(mp, bp))
260 		xfs_buf_ioerror(bp, -EFSBADCRC);
261 	else if (!xfs_dquot_buf_verify(mp, bp))
262 		xfs_buf_ioerror(bp, -EFSCORRUPTED);
263 
264 	if (bp->b_error)
265 		xfs_verifier_error(bp);
266 }
267 
268 /*
269  * we don't calculate the CRC here as that is done when the dquot is flushed to
270  * the buffer after the update is done. This ensures that the dquot in the
271  * buffer always has an up-to-date CRC value.
272  */
273 static void
274 xfs_dquot_buf_write_verify(
275 	struct xfs_buf	*bp)
276 {
277 	struct xfs_mount	*mp = bp->b_target->bt_mount;
278 
279 	if (!xfs_dquot_buf_verify(mp, bp)) {
280 		xfs_buf_ioerror(bp, -EFSCORRUPTED);
281 		xfs_verifier_error(bp);
282 		return;
283 	}
284 }
285 
286 const struct xfs_buf_ops xfs_dquot_buf_ops = {
287 	.verify_read = xfs_dquot_buf_read_verify,
288 	.verify_write = xfs_dquot_buf_write_verify,
289 };
290 
291