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