xref: /linux/fs/xfs/xfs_attr_inactive.c (revision c532de5a67a70f8533d495f8f2aaa9a0491c3ad0)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2000-2005 Silicon Graphics, Inc.
4  * Copyright (c) 2013 Red Hat, Inc.
5  * All Rights Reserved.
6  */
7 #include "xfs.h"
8 #include "xfs_fs.h"
9 #include "xfs_shared.h"
10 #include "xfs_format.h"
11 #include "xfs_log_format.h"
12 #include "xfs_trans_resv.h"
13 #include "xfs_bit.h"
14 #include "xfs_mount.h"
15 #include "xfs_da_format.h"
16 #include "xfs_da_btree.h"
17 #include "xfs_inode.h"
18 #include "xfs_attr.h"
19 #include "xfs_attr_remote.h"
20 #include "xfs_trans.h"
21 #include "xfs_bmap.h"
22 #include "xfs_attr_leaf.h"
23 #include "xfs_quota.h"
24 #include "xfs_dir2.h"
25 #include "xfs_error.h"
26 #include "xfs_health.h"
27 
28 /*
29  * Invalidate any incore buffers associated with this remote attribute value
30  * extent.   We never log remote attribute value buffers, which means that they
31  * won't be attached to a transaction and are therefore safe to mark stale.
32  * The actual bunmapi will be taken care of later.
33  */
34 STATIC int
35 xfs_attr3_rmt_stale(
36 	struct xfs_inode	*dp,
37 	xfs_dablk_t		blkno,
38 	int			blkcnt)
39 {
40 	struct xfs_bmbt_irec	map;
41 	int			nmap;
42 	int			error;
43 
44 	/*
45 	 * Roll through the "value", invalidating the attribute value's
46 	 * blocks.
47 	 */
48 	while (blkcnt > 0) {
49 		/*
50 		 * Try to remember where we decided to put the value.
51 		 */
52 		nmap = 1;
53 		error = xfs_bmapi_read(dp, (xfs_fileoff_t)blkno, blkcnt,
54 				       &map, &nmap, XFS_BMAPI_ATTRFORK);
55 		if (error)
56 			return error;
57 		if (XFS_IS_CORRUPT(dp->i_mount, nmap != 1))
58 			return -EFSCORRUPTED;
59 
60 		/*
61 		 * Mark any incore buffers for the remote value as stale.  We
62 		 * never log remote attr value buffers, so the buffer should be
63 		 * easy to kill.
64 		 */
65 		error = xfs_attr_rmtval_stale(dp, &map, 0);
66 		if (error)
67 			return error;
68 
69 		blkno += map.br_blockcount;
70 		blkcnt -= map.br_blockcount;
71 	}
72 
73 	return 0;
74 }
75 
76 /*
77  * Invalidate all of the "remote" value regions pointed to by a particular
78  * leaf block.
79  * Note that we must release the lock on the buffer so that we are not
80  * caught holding something that the logging code wants to flush to disk.
81  */
82 STATIC int
83 xfs_attr3_leaf_inactive(
84 	struct xfs_trans		**trans,
85 	struct xfs_inode		*dp,
86 	struct xfs_buf			*bp)
87 {
88 	struct xfs_attr3_icleaf_hdr	ichdr;
89 	struct xfs_mount		*mp = bp->b_mount;
90 	struct xfs_attr_leafblock	*leaf = bp->b_addr;
91 	struct xfs_attr_leaf_entry	*entry;
92 	struct xfs_attr_leaf_name_remote *name_rmt;
93 	int				error = 0;
94 	int				i;
95 
96 	xfs_attr3_leaf_hdr_from_disk(mp->m_attr_geo, &ichdr, leaf);
97 
98 	/*
99 	 * Find the remote value extents for this leaf and invalidate their
100 	 * incore buffers.
101 	 */
102 	entry = xfs_attr3_leaf_entryp(leaf);
103 	for (i = 0; i < ichdr.count; entry++, i++) {
104 		int		blkcnt;
105 
106 		if (!entry->nameidx || (entry->flags & XFS_ATTR_LOCAL))
107 			continue;
108 
109 		name_rmt = xfs_attr3_leaf_name_remote(leaf, i);
110 		if (!name_rmt->valueblk)
111 			continue;
112 
113 		blkcnt = xfs_attr3_rmt_blocks(dp->i_mount,
114 				be32_to_cpu(name_rmt->valuelen));
115 		error = xfs_attr3_rmt_stale(dp,
116 				be32_to_cpu(name_rmt->valueblk), blkcnt);
117 		if (error)
118 			goto err;
119 	}
120 
121 	xfs_trans_brelse(*trans, bp);
122 err:
123 	return error;
124 }
125 
126 /*
127  * Recurse (gasp!) through the attribute nodes until we find leaves.
128  * We're doing a depth-first traversal in order to invalidate everything.
129  */
130 STATIC int
131 xfs_attr3_node_inactive(
132 	struct xfs_trans	**trans,
133 	struct xfs_inode	*dp,
134 	struct xfs_buf		*bp,
135 	int			level)
136 {
137 	struct xfs_mount	*mp = dp->i_mount;
138 	struct xfs_da_blkinfo	*info;
139 	xfs_dablk_t		child_fsb;
140 	xfs_daddr_t		parent_blkno, child_blkno;
141 	struct xfs_buf		*child_bp;
142 	struct xfs_da3_icnode_hdr ichdr;
143 	int			error, i;
144 
145 	/*
146 	 * Since this code is recursive (gasp!) we must protect ourselves.
147 	 */
148 	if (level > XFS_DA_NODE_MAXDEPTH) {
149 		xfs_buf_mark_corrupt(bp);
150 		xfs_trans_brelse(*trans, bp);	/* no locks for later trans */
151 		xfs_dirattr_mark_sick(dp, XFS_ATTR_FORK);
152 		return -EFSCORRUPTED;
153 	}
154 
155 	xfs_da3_node_hdr_from_disk(dp->i_mount, &ichdr, bp->b_addr);
156 	parent_blkno = xfs_buf_daddr(bp);
157 	if (!ichdr.count) {
158 		xfs_trans_brelse(*trans, bp);
159 		return 0;
160 	}
161 	child_fsb = be32_to_cpu(ichdr.btree[0].before);
162 	xfs_trans_brelse(*trans, bp);	/* no locks for later trans */
163 	bp = NULL;
164 
165 	/*
166 	 * If this is the node level just above the leaves, simply loop
167 	 * over the leaves removing all of them.  If this is higher up
168 	 * in the tree, recurse downward.
169 	 */
170 	for (i = 0; i < ichdr.count; i++) {
171 		/*
172 		 * Read the subsidiary block to see what we have to work with.
173 		 * Don't do this in a transaction.  This is a depth-first
174 		 * traversal of the tree so we may deal with many blocks
175 		 * before we come back to this one.
176 		 */
177 		error = xfs_da3_node_read(*trans, dp, child_fsb, &child_bp,
178 					  XFS_ATTR_FORK);
179 		if (error)
180 			return error;
181 
182 		/* save for re-read later */
183 		child_blkno = xfs_buf_daddr(child_bp);
184 
185 		/*
186 		 * Invalidate the subtree, however we have to.
187 		 */
188 		info = child_bp->b_addr;
189 		switch (info->magic) {
190 		case cpu_to_be16(XFS_DA_NODE_MAGIC):
191 		case cpu_to_be16(XFS_DA3_NODE_MAGIC):
192 			error = xfs_attr3_node_inactive(trans, dp, child_bp,
193 							level + 1);
194 			break;
195 		case cpu_to_be16(XFS_ATTR_LEAF_MAGIC):
196 		case cpu_to_be16(XFS_ATTR3_LEAF_MAGIC):
197 			error = xfs_attr3_leaf_inactive(trans, dp, child_bp);
198 			break;
199 		default:
200 			xfs_buf_mark_corrupt(child_bp);
201 			xfs_trans_brelse(*trans, child_bp);
202 			xfs_dirattr_mark_sick(dp, XFS_ATTR_FORK);
203 			error = -EFSCORRUPTED;
204 			break;
205 		}
206 		if (error)
207 			return error;
208 
209 		/*
210 		 * Remove the subsidiary block from the cache and from the log.
211 		 */
212 		error = xfs_trans_get_buf(*trans, mp->m_ddev_targp,
213 				child_blkno,
214 				XFS_FSB_TO_BB(mp, mp->m_attr_geo->fsbcount), 0,
215 				&child_bp);
216 		if (error)
217 			return error;
218 		xfs_trans_binval(*trans, child_bp);
219 		child_bp = NULL;
220 
221 		/*
222 		 * If we're not done, re-read the parent to get the next
223 		 * child block number.
224 		 */
225 		if (i + 1 < ichdr.count) {
226 			struct xfs_da3_icnode_hdr phdr;
227 
228 			error = xfs_da3_node_read_mapped(*trans, dp,
229 					parent_blkno, &bp, XFS_ATTR_FORK);
230 			if (error)
231 				return error;
232 			xfs_da3_node_hdr_from_disk(dp->i_mount, &phdr,
233 						  bp->b_addr);
234 			child_fsb = be32_to_cpu(phdr.btree[i + 1].before);
235 			xfs_trans_brelse(*trans, bp);
236 			bp = NULL;
237 		}
238 		/*
239 		 * Atomically commit the whole invalidate stuff.
240 		 */
241 		error = xfs_trans_roll_inode(trans, dp);
242 		if (error)
243 			return  error;
244 	}
245 
246 	return 0;
247 }
248 
249 /*
250  * Indiscriminately delete the entire attribute fork
251  *
252  * Recurse (gasp!) through the attribute nodes until we find leaves.
253  * We're doing a depth-first traversal in order to invalidate everything.
254  */
255 static int
256 xfs_attr3_root_inactive(
257 	struct xfs_trans	**trans,
258 	struct xfs_inode	*dp)
259 {
260 	struct xfs_mount	*mp = dp->i_mount;
261 	struct xfs_da_blkinfo	*info;
262 	struct xfs_buf		*bp;
263 	xfs_daddr_t		blkno;
264 	int			error;
265 
266 	/*
267 	 * Read block 0 to see what we have to work with.
268 	 * We only get here if we have extents, since we remove
269 	 * the extents in reverse order the extent containing
270 	 * block 0 must still be there.
271 	 */
272 	error = xfs_da3_node_read(*trans, dp, 0, &bp, XFS_ATTR_FORK);
273 	if (error)
274 		return error;
275 	blkno = xfs_buf_daddr(bp);
276 
277 	/*
278 	 * Invalidate the tree, even if the "tree" is only a single leaf block.
279 	 * This is a depth-first traversal!
280 	 */
281 	info = bp->b_addr;
282 	switch (info->magic) {
283 	case cpu_to_be16(XFS_DA_NODE_MAGIC):
284 	case cpu_to_be16(XFS_DA3_NODE_MAGIC):
285 		error = xfs_attr3_node_inactive(trans, dp, bp, 1);
286 		break;
287 	case cpu_to_be16(XFS_ATTR_LEAF_MAGIC):
288 	case cpu_to_be16(XFS_ATTR3_LEAF_MAGIC):
289 		error = xfs_attr3_leaf_inactive(trans, dp, bp);
290 		break;
291 	default:
292 		xfs_dirattr_mark_sick(dp, XFS_ATTR_FORK);
293 		error = -EFSCORRUPTED;
294 		xfs_buf_mark_corrupt(bp);
295 		xfs_trans_brelse(*trans, bp);
296 		break;
297 	}
298 	if (error)
299 		return error;
300 
301 	/*
302 	 * Invalidate the incore copy of the root block.
303 	 */
304 	error = xfs_trans_get_buf(*trans, mp->m_ddev_targp, blkno,
305 			XFS_FSB_TO_BB(mp, mp->m_attr_geo->fsbcount), 0, &bp);
306 	if (error)
307 		return error;
308 	error = bp->b_error;
309 	if (error) {
310 		xfs_trans_brelse(*trans, bp);
311 		return error;
312 	}
313 	xfs_trans_binval(*trans, bp);	/* remove from cache */
314 	/*
315 	 * Commit the invalidate and start the next transaction.
316 	 */
317 	error = xfs_trans_roll_inode(trans, dp);
318 
319 	return error;
320 }
321 
322 /*
323  * xfs_attr_inactive kills all traces of an attribute fork on an inode. It
324  * removes both the on-disk and in-memory inode fork. Note that this also has to
325  * handle the condition of inodes without attributes but with an attribute fork
326  * configured, so we can't use xfs_inode_hasattr() here.
327  *
328  * The in-memory attribute fork is removed even on error.
329  */
330 int
331 xfs_attr_inactive(
332 	struct xfs_inode	*dp)
333 {
334 	struct xfs_trans	*trans;
335 	struct xfs_mount	*mp;
336 	int			lock_mode = XFS_ILOCK_SHARED;
337 	int			error = 0;
338 
339 	mp = dp->i_mount;
340 
341 	xfs_ilock(dp, lock_mode);
342 	if (!xfs_inode_has_attr_fork(dp))
343 		goto out_destroy_fork;
344 	xfs_iunlock(dp, lock_mode);
345 
346 	lock_mode = 0;
347 
348 	error = xfs_trans_alloc(mp, &M_RES(mp)->tr_attrinval, 0, 0, 0, &trans);
349 	if (error)
350 		goto out_destroy_fork;
351 
352 	lock_mode = XFS_ILOCK_EXCL;
353 	xfs_ilock(dp, lock_mode);
354 
355 	if (!xfs_inode_has_attr_fork(dp))
356 		goto out_cancel;
357 
358 	/*
359 	 * No need to make quota reservations here. We expect to release some
360 	 * blocks, not allocate, in the common case.
361 	 */
362 	xfs_trans_ijoin(trans, dp, 0);
363 
364 	/*
365 	 * Invalidate and truncate the attribute fork extents. Make sure the
366 	 * fork actually has xattr blocks as otherwise the invalidation has no
367 	 * blocks to read and returns an error. In this case, just do the fork
368 	 * removal below.
369 	 */
370 	if (dp->i_af.if_nextents > 0) {
371 		error = xfs_attr3_root_inactive(&trans, dp);
372 		if (error)
373 			goto out_cancel;
374 
375 		error = xfs_itruncate_extents(&trans, dp, XFS_ATTR_FORK, 0);
376 		if (error)
377 			goto out_cancel;
378 	}
379 
380 	/* Reset the attribute fork - this also destroys the in-core fork */
381 	xfs_attr_fork_remove(dp, trans);
382 
383 	error = xfs_trans_commit(trans);
384 	xfs_iunlock(dp, lock_mode);
385 	return error;
386 
387 out_cancel:
388 	xfs_trans_cancel(trans);
389 out_destroy_fork:
390 	/* kill the in-core attr fork before we drop the inode lock */
391 	xfs_ifork_zap_attr(dp);
392 	if (lock_mode)
393 		xfs_iunlock(dp, lock_mode);
394 	return error;
395 }
396