xref: /openbmc/linux/fs/xfs/xfs_attr_inactive.c (revision b9b77222)
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_alloc.h"
19 #include "xfs_attr_remote.h"
20 #include "xfs_trans.h"
21 #include "xfs_inode_item.h"
22 #include "xfs_bmap.h"
23 #include "xfs_attr.h"
24 #include "xfs_attr_leaf.h"
25 #include "xfs_error.h"
26 #include "xfs_quota.h"
27 #include "xfs_trace.h"
28 #include "xfs_dir2.h"
29 
30 /*
31  * Look at all the extents for this logical region,
32  * invalidate any buffers that are incore/in transactions.
33  */
34 STATIC int
35 xfs_attr3_leaf_freextent(
36 	struct xfs_trans	**trans,
37 	struct xfs_inode	*dp,
38 	xfs_dablk_t		blkno,
39 	int			blkcnt)
40 {
41 	struct xfs_bmbt_irec	map;
42 	struct xfs_buf		*bp;
43 	xfs_dablk_t		tblkno;
44 	xfs_daddr_t		dblkno;
45 	int			tblkcnt;
46 	int			dblkcnt;
47 	int			nmap;
48 	int			error;
49 
50 	/*
51 	 * Roll through the "value", invalidating the attribute value's
52 	 * blocks.
53 	 */
54 	tblkno = blkno;
55 	tblkcnt = blkcnt;
56 	while (tblkcnt > 0) {
57 		/*
58 		 * Try to remember where we decided to put the value.
59 		 */
60 		nmap = 1;
61 		error = xfs_bmapi_read(dp, (xfs_fileoff_t)tblkno, tblkcnt,
62 				       &map, &nmap, XFS_BMAPI_ATTRFORK);
63 		if (error) {
64 			return error;
65 		}
66 		ASSERT(nmap == 1);
67 		ASSERT(map.br_startblock != DELAYSTARTBLOCK);
68 
69 		/*
70 		 * If it's a hole, these are already unmapped
71 		 * so there's nothing to invalidate.
72 		 */
73 		if (map.br_startblock != HOLESTARTBLOCK) {
74 
75 			dblkno = XFS_FSB_TO_DADDR(dp->i_mount,
76 						  map.br_startblock);
77 			dblkcnt = XFS_FSB_TO_BB(dp->i_mount,
78 						map.br_blockcount);
79 			bp = xfs_trans_get_buf(*trans,
80 					dp->i_mount->m_ddev_targp,
81 					dblkno, dblkcnt, 0);
82 			if (!bp)
83 				return -ENOMEM;
84 			xfs_trans_binval(*trans, bp);
85 			/*
86 			 * Roll to next transaction.
87 			 */
88 			error = xfs_trans_roll_inode(trans, dp);
89 			if (error)
90 				return error;
91 		}
92 
93 		tblkno += map.br_blockcount;
94 		tblkcnt -= map.br_blockcount;
95 	}
96 
97 	return 0;
98 }
99 
100 /*
101  * Invalidate all of the "remote" value regions pointed to by a particular
102  * leaf block.
103  * Note that we must release the lock on the buffer so that we are not
104  * caught holding something that the logging code wants to flush to disk.
105  */
106 STATIC int
107 xfs_attr3_leaf_inactive(
108 	struct xfs_trans	**trans,
109 	struct xfs_inode	*dp,
110 	struct xfs_buf		*bp)
111 {
112 	struct xfs_attr_leafblock *leaf;
113 	struct xfs_attr3_icleaf_hdr ichdr;
114 	struct xfs_attr_leaf_entry *entry;
115 	struct xfs_attr_leaf_name_remote *name_rmt;
116 	struct xfs_attr_inactive_list *list;
117 	struct xfs_attr_inactive_list *lp;
118 	int			error;
119 	int			count;
120 	int			size;
121 	int			tmp;
122 	int			i;
123 	struct xfs_mount	*mp = bp->b_target->bt_mount;
124 
125 	leaf = bp->b_addr;
126 	xfs_attr3_leaf_hdr_from_disk(mp->m_attr_geo, &ichdr, leaf);
127 
128 	/*
129 	 * Count the number of "remote" value extents.
130 	 */
131 	count = 0;
132 	entry = xfs_attr3_leaf_entryp(leaf);
133 	for (i = 0; i < ichdr.count; entry++, i++) {
134 		if (be16_to_cpu(entry->nameidx) &&
135 		    ((entry->flags & XFS_ATTR_LOCAL) == 0)) {
136 			name_rmt = xfs_attr3_leaf_name_remote(leaf, i);
137 			if (name_rmt->valueblk)
138 				count++;
139 		}
140 	}
141 
142 	/*
143 	 * If there are no "remote" values, we're done.
144 	 */
145 	if (count == 0) {
146 		xfs_trans_brelse(*trans, bp);
147 		return 0;
148 	}
149 
150 	/*
151 	 * Allocate storage for a list of all the "remote" value extents.
152 	 */
153 	size = count * sizeof(xfs_attr_inactive_list_t);
154 	list = kmem_alloc(size, KM_SLEEP);
155 
156 	/*
157 	 * Identify each of the "remote" value extents.
158 	 */
159 	lp = list;
160 	entry = xfs_attr3_leaf_entryp(leaf);
161 	for (i = 0; i < ichdr.count; entry++, i++) {
162 		if (be16_to_cpu(entry->nameidx) &&
163 		    ((entry->flags & XFS_ATTR_LOCAL) == 0)) {
164 			name_rmt = xfs_attr3_leaf_name_remote(leaf, i);
165 			if (name_rmt->valueblk) {
166 				lp->valueblk = be32_to_cpu(name_rmt->valueblk);
167 				lp->valuelen = xfs_attr3_rmt_blocks(dp->i_mount,
168 						    be32_to_cpu(name_rmt->valuelen));
169 				lp++;
170 			}
171 		}
172 	}
173 	xfs_trans_brelse(*trans, bp);	/* unlock for trans. in freextent() */
174 
175 	/*
176 	 * Invalidate each of the "remote" value extents.
177 	 */
178 	error = 0;
179 	for (lp = list, i = 0; i < count; i++, lp++) {
180 		tmp = xfs_attr3_leaf_freextent(trans, dp,
181 				lp->valueblk, lp->valuelen);
182 
183 		if (error == 0)
184 			error = tmp;	/* save only the 1st errno */
185 	}
186 
187 	kmem_free(list);
188 	return error;
189 }
190 
191 /*
192  * Recurse (gasp!) through the attribute nodes until we find leaves.
193  * We're doing a depth-first traversal in order to invalidate everything.
194  */
195 STATIC int
196 xfs_attr3_node_inactive(
197 	struct xfs_trans **trans,
198 	struct xfs_inode *dp,
199 	struct xfs_buf	*bp,
200 	int		level)
201 {
202 	xfs_da_blkinfo_t *info;
203 	xfs_da_intnode_t *node;
204 	xfs_dablk_t child_fsb;
205 	xfs_daddr_t parent_blkno, child_blkno;
206 	int error, i;
207 	struct xfs_buf *child_bp;
208 	struct xfs_da_node_entry *btree;
209 	struct xfs_da3_icnode_hdr ichdr;
210 
211 	/*
212 	 * Since this code is recursive (gasp!) we must protect ourselves.
213 	 */
214 	if (level > XFS_DA_NODE_MAXDEPTH) {
215 		xfs_trans_brelse(*trans, bp);	/* no locks for later trans */
216 		return -EIO;
217 	}
218 
219 	node = bp->b_addr;
220 	dp->d_ops->node_hdr_from_disk(&ichdr, node);
221 	parent_blkno = bp->b_bn;
222 	if (!ichdr.count) {
223 		xfs_trans_brelse(*trans, bp);
224 		return 0;
225 	}
226 	btree = dp->d_ops->node_tree_p(node);
227 	child_fsb = be32_to_cpu(btree[0].before);
228 	xfs_trans_brelse(*trans, bp);	/* no locks for later trans */
229 
230 	/*
231 	 * If this is the node level just above the leaves, simply loop
232 	 * over the leaves removing all of them.  If this is higher up
233 	 * in the tree, recurse downward.
234 	 */
235 	for (i = 0; i < ichdr.count; i++) {
236 		/*
237 		 * Read the subsidiary block to see what we have to work with.
238 		 * Don't do this in a transaction.  This is a depth-first
239 		 * traversal of the tree so we may deal with many blocks
240 		 * before we come back to this one.
241 		 */
242 		error = xfs_da3_node_read(*trans, dp, child_fsb, -1, &child_bp,
243 					  XFS_ATTR_FORK);
244 		if (error)
245 			return error;
246 
247 		/* save for re-read later */
248 		child_blkno = XFS_BUF_ADDR(child_bp);
249 
250 		/*
251 		 * Invalidate the subtree, however we have to.
252 		 */
253 		info = child_bp->b_addr;
254 		switch (info->magic) {
255 		case cpu_to_be16(XFS_DA_NODE_MAGIC):
256 		case cpu_to_be16(XFS_DA3_NODE_MAGIC):
257 			error = xfs_attr3_node_inactive(trans, dp, child_bp,
258 							level + 1);
259 			break;
260 		case cpu_to_be16(XFS_ATTR_LEAF_MAGIC):
261 		case cpu_to_be16(XFS_ATTR3_LEAF_MAGIC):
262 			error = xfs_attr3_leaf_inactive(trans, dp, child_bp);
263 			break;
264 		default:
265 			error = -EIO;
266 			xfs_trans_brelse(*trans, child_bp);
267 			break;
268 		}
269 		if (error)
270 			return error;
271 
272 		/*
273 		 * Remove the subsidiary block from the cache and from the log.
274 		 */
275 		error = xfs_da_get_buf(*trans, dp, 0, child_blkno, &child_bp,
276 				       XFS_ATTR_FORK);
277 		if (error)
278 			return error;
279 		xfs_trans_binval(*trans, child_bp);
280 
281 		/*
282 		 * If we're not done, re-read the parent to get the next
283 		 * child block number.
284 		 */
285 		if (i + 1 < ichdr.count) {
286 			error = xfs_da3_node_read(*trans, dp, 0, parent_blkno,
287 						 &bp, XFS_ATTR_FORK);
288 			if (error)
289 				return error;
290 			node = bp->b_addr;
291 			btree = dp->d_ops->node_tree_p(node);
292 			child_fsb = be32_to_cpu(btree[i + 1].before);
293 			xfs_trans_brelse(*trans, bp);
294 		}
295 		/*
296 		 * Atomically commit the whole invalidate stuff.
297 		 */
298 		error = xfs_trans_roll_inode(trans, dp);
299 		if (error)
300 			return  error;
301 	}
302 
303 	return 0;
304 }
305 
306 /*
307  * Indiscriminately delete the entire attribute fork
308  *
309  * Recurse (gasp!) through the attribute nodes until we find leaves.
310  * We're doing a depth-first traversal in order to invalidate everything.
311  */
312 static int
313 xfs_attr3_root_inactive(
314 	struct xfs_trans	**trans,
315 	struct xfs_inode	*dp)
316 {
317 	struct xfs_da_blkinfo	*info;
318 	struct xfs_buf		*bp;
319 	xfs_daddr_t		blkno;
320 	int			error;
321 
322 	/*
323 	 * Read block 0 to see what we have to work with.
324 	 * We only get here if we have extents, since we remove
325 	 * the extents in reverse order the extent containing
326 	 * block 0 must still be there.
327 	 */
328 	error = xfs_da3_node_read(*trans, dp, 0, -1, &bp, XFS_ATTR_FORK);
329 	if (error)
330 		return error;
331 	blkno = bp->b_bn;
332 
333 	/*
334 	 * Invalidate the tree, even if the "tree" is only a single leaf block.
335 	 * This is a depth-first traversal!
336 	 */
337 	info = bp->b_addr;
338 	switch (info->magic) {
339 	case cpu_to_be16(XFS_DA_NODE_MAGIC):
340 	case cpu_to_be16(XFS_DA3_NODE_MAGIC):
341 		error = xfs_attr3_node_inactive(trans, dp, bp, 1);
342 		break;
343 	case cpu_to_be16(XFS_ATTR_LEAF_MAGIC):
344 	case cpu_to_be16(XFS_ATTR3_LEAF_MAGIC):
345 		error = xfs_attr3_leaf_inactive(trans, dp, bp);
346 		break;
347 	default:
348 		error = -EIO;
349 		xfs_trans_brelse(*trans, bp);
350 		break;
351 	}
352 	if (error)
353 		return error;
354 
355 	/*
356 	 * Invalidate the incore copy of the root block.
357 	 */
358 	error = xfs_da_get_buf(*trans, dp, 0, blkno, &bp, XFS_ATTR_FORK);
359 	if (error)
360 		return error;
361 	xfs_trans_binval(*trans, bp);	/* remove from cache */
362 	/*
363 	 * Commit the invalidate and start the next transaction.
364 	 */
365 	error = xfs_trans_roll_inode(trans, dp);
366 
367 	return error;
368 }
369 
370 /*
371  * xfs_attr_inactive kills all traces of an attribute fork on an inode. It
372  * removes both the on-disk and in-memory inode fork. Note that this also has to
373  * handle the condition of inodes without attributes but with an attribute fork
374  * configured, so we can't use xfs_inode_hasattr() here.
375  *
376  * The in-memory attribute fork is removed even on error.
377  */
378 int
379 xfs_attr_inactive(
380 	struct xfs_inode	*dp)
381 {
382 	struct xfs_trans	*trans;
383 	struct xfs_mount	*mp;
384 	int			lock_mode = XFS_ILOCK_SHARED;
385 	int			error = 0;
386 
387 	mp = dp->i_mount;
388 	ASSERT(! XFS_NOT_DQATTACHED(mp, dp));
389 
390 	xfs_ilock(dp, lock_mode);
391 	if (!XFS_IFORK_Q(dp))
392 		goto out_destroy_fork;
393 	xfs_iunlock(dp, lock_mode);
394 
395 	lock_mode = 0;
396 
397 	error = xfs_trans_alloc(mp, &M_RES(mp)->tr_attrinval, 0, 0, 0, &trans);
398 	if (error)
399 		goto out_destroy_fork;
400 
401 	lock_mode = XFS_ILOCK_EXCL;
402 	xfs_ilock(dp, lock_mode);
403 
404 	if (!XFS_IFORK_Q(dp))
405 		goto out_cancel;
406 
407 	/*
408 	 * No need to make quota reservations here. We expect to release some
409 	 * blocks, not allocate, in the common case.
410 	 */
411 	xfs_trans_ijoin(trans, dp, 0);
412 
413 	/*
414 	 * Invalidate and truncate the attribute fork extents. Make sure the
415 	 * fork actually has attributes as otherwise the invalidation has no
416 	 * blocks to read and returns an error. In this case, just do the fork
417 	 * removal below.
418 	 */
419 	if (xfs_inode_hasattr(dp) &&
420 	    dp->i_d.di_aformat != XFS_DINODE_FMT_LOCAL) {
421 		error = xfs_attr3_root_inactive(&trans, dp);
422 		if (error)
423 			goto out_cancel;
424 
425 		error = xfs_itruncate_extents(&trans, dp, XFS_ATTR_FORK, 0);
426 		if (error)
427 			goto out_cancel;
428 	}
429 
430 	/* Reset the attribute fork - this also destroys the in-core fork */
431 	xfs_attr_fork_remove(dp, trans);
432 
433 	error = xfs_trans_commit(trans);
434 	xfs_iunlock(dp, lock_mode);
435 	return error;
436 
437 out_cancel:
438 	xfs_trans_cancel(trans);
439 out_destroy_fork:
440 	/* kill the in-core attr fork before we drop the inode lock */
441 	if (dp->i_afp)
442 		xfs_idestroy_fork(dp, XFS_ATTR_FORK);
443 	if (lock_mode)
444 		xfs_iunlock(dp, lock_mode);
445 	return error;
446 }
447