xref: /openbmc/linux/fs/xfs/xfs_attr_inactive.c (revision 0c874100)
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 #include "xfs_defer.h"
30 
31 /*
32  * Look at all the extents for this logical region,
33  * invalidate any buffers that are incore/in transactions.
34  */
35 STATIC int
36 xfs_attr3_leaf_freextent(
37 	struct xfs_trans	**trans,
38 	struct xfs_inode	*dp,
39 	xfs_dablk_t		blkno,
40 	int			blkcnt)
41 {
42 	struct xfs_bmbt_irec	map;
43 	struct xfs_buf		*bp;
44 	xfs_dablk_t		tblkno;
45 	xfs_daddr_t		dblkno;
46 	int			tblkcnt;
47 	int			dblkcnt;
48 	int			nmap;
49 	int			error;
50 
51 	/*
52 	 * Roll through the "value", invalidating the attribute value's
53 	 * blocks.
54 	 */
55 	tblkno = blkno;
56 	tblkcnt = blkcnt;
57 	while (tblkcnt > 0) {
58 		/*
59 		 * Try to remember where we decided to put the value.
60 		 */
61 		nmap = 1;
62 		error = xfs_bmapi_read(dp, (xfs_fileoff_t)tblkno, tblkcnt,
63 				       &map, &nmap, XFS_BMAPI_ATTRFORK);
64 		if (error) {
65 			return error;
66 		}
67 		ASSERT(nmap == 1);
68 		ASSERT(map.br_startblock != DELAYSTARTBLOCK);
69 
70 		/*
71 		 * If it's a hole, these are already unmapped
72 		 * so there's nothing to invalidate.
73 		 */
74 		if (map.br_startblock != HOLESTARTBLOCK) {
75 
76 			dblkno = XFS_FSB_TO_DADDR(dp->i_mount,
77 						  map.br_startblock);
78 			dblkcnt = XFS_FSB_TO_BB(dp->i_mount,
79 						map.br_blockcount);
80 			bp = xfs_trans_get_buf(*trans,
81 					dp->i_mount->m_ddev_targp,
82 					dblkno, dblkcnt, 0);
83 			if (!bp)
84 				return -ENOMEM;
85 			xfs_trans_binval(*trans, bp);
86 			/*
87 			 * Roll to next transaction.
88 			 */
89 			error = xfs_trans_roll_inode(trans, dp);
90 			if (error)
91 				return error;
92 		}
93 
94 		tblkno += map.br_blockcount;
95 		tblkcnt -= map.br_blockcount;
96 	}
97 
98 	return 0;
99 }
100 
101 /*
102  * Invalidate all of the "remote" value regions pointed to by a particular
103  * leaf block.
104  * Note that we must release the lock on the buffer so that we are not
105  * caught holding something that the logging code wants to flush to disk.
106  */
107 STATIC int
108 xfs_attr3_leaf_inactive(
109 	struct xfs_trans	**trans,
110 	struct xfs_inode	*dp,
111 	struct xfs_buf		*bp)
112 {
113 	struct xfs_attr_leafblock *leaf;
114 	struct xfs_attr3_icleaf_hdr ichdr;
115 	struct xfs_attr_leaf_entry *entry;
116 	struct xfs_attr_leaf_name_remote *name_rmt;
117 	struct xfs_attr_inactive_list *list;
118 	struct xfs_attr_inactive_list *lp;
119 	int			error;
120 	int			count;
121 	int			size;
122 	int			tmp;
123 	int			i;
124 	struct xfs_mount	*mp = bp->b_target->bt_mount;
125 
126 	leaf = bp->b_addr;
127 	xfs_attr3_leaf_hdr_from_disk(mp->m_attr_geo, &ichdr, leaf);
128 
129 	/*
130 	 * Count the number of "remote" value extents.
131 	 */
132 	count = 0;
133 	entry = xfs_attr3_leaf_entryp(leaf);
134 	for (i = 0; i < ichdr.count; entry++, i++) {
135 		if (be16_to_cpu(entry->nameidx) &&
136 		    ((entry->flags & XFS_ATTR_LOCAL) == 0)) {
137 			name_rmt = xfs_attr3_leaf_name_remote(leaf, i);
138 			if (name_rmt->valueblk)
139 				count++;
140 		}
141 	}
142 
143 	/*
144 	 * If there are no "remote" values, we're done.
145 	 */
146 	if (count == 0) {
147 		xfs_trans_brelse(*trans, bp);
148 		return 0;
149 	}
150 
151 	/*
152 	 * Allocate storage for a list of all the "remote" value extents.
153 	 */
154 	size = count * sizeof(xfs_attr_inactive_list_t);
155 	list = kmem_alloc(size, KM_SLEEP);
156 
157 	/*
158 	 * Identify each of the "remote" value extents.
159 	 */
160 	lp = list;
161 	entry = xfs_attr3_leaf_entryp(leaf);
162 	for (i = 0; i < ichdr.count; entry++, i++) {
163 		if (be16_to_cpu(entry->nameidx) &&
164 		    ((entry->flags & XFS_ATTR_LOCAL) == 0)) {
165 			name_rmt = xfs_attr3_leaf_name_remote(leaf, i);
166 			if (name_rmt->valueblk) {
167 				lp->valueblk = be32_to_cpu(name_rmt->valueblk);
168 				lp->valuelen = xfs_attr3_rmt_blocks(dp->i_mount,
169 						    be32_to_cpu(name_rmt->valuelen));
170 				lp++;
171 			}
172 		}
173 	}
174 	xfs_trans_brelse(*trans, bp);	/* unlock for trans. in freextent() */
175 
176 	/*
177 	 * Invalidate each of the "remote" value extents.
178 	 */
179 	error = 0;
180 	for (lp = list, i = 0; i < count; i++, lp++) {
181 		tmp = xfs_attr3_leaf_freextent(trans, dp,
182 				lp->valueblk, lp->valuelen);
183 
184 		if (error == 0)
185 			error = tmp;	/* save only the 1st errno */
186 	}
187 
188 	kmem_free(list);
189 	return error;
190 }
191 
192 /*
193  * Recurse (gasp!) through the attribute nodes until we find leaves.
194  * We're doing a depth-first traversal in order to invalidate everything.
195  */
196 STATIC int
197 xfs_attr3_node_inactive(
198 	struct xfs_trans **trans,
199 	struct xfs_inode *dp,
200 	struct xfs_buf	*bp,
201 	int		level)
202 {
203 	xfs_da_blkinfo_t *info;
204 	xfs_da_intnode_t *node;
205 	xfs_dablk_t child_fsb;
206 	xfs_daddr_t parent_blkno, child_blkno;
207 	int error, i;
208 	struct xfs_buf *child_bp;
209 	struct xfs_da_node_entry *btree;
210 	struct xfs_da3_icnode_hdr ichdr;
211 
212 	/*
213 	 * Since this code is recursive (gasp!) we must protect ourselves.
214 	 */
215 	if (level > XFS_DA_NODE_MAXDEPTH) {
216 		xfs_trans_brelse(*trans, bp);	/* no locks for later trans */
217 		return -EIO;
218 	}
219 
220 	node = bp->b_addr;
221 	dp->d_ops->node_hdr_from_disk(&ichdr, node);
222 	parent_blkno = bp->b_bn;
223 	if (!ichdr.count) {
224 		xfs_trans_brelse(*trans, bp);
225 		return 0;
226 	}
227 	btree = dp->d_ops->node_tree_p(node);
228 	child_fsb = be32_to_cpu(btree[0].before);
229 	xfs_trans_brelse(*trans, bp);	/* no locks for later trans */
230 
231 	/*
232 	 * If this is the node level just above the leaves, simply loop
233 	 * over the leaves removing all of them.  If this is higher up
234 	 * in the tree, recurse downward.
235 	 */
236 	for (i = 0; i < ichdr.count; i++) {
237 		/*
238 		 * Read the subsidiary block to see what we have to work with.
239 		 * Don't do this in a transaction.  This is a depth-first
240 		 * traversal of the tree so we may deal with many blocks
241 		 * before we come back to this one.
242 		 */
243 		error = xfs_da3_node_read(*trans, dp, child_fsb, -1, &child_bp,
244 					  XFS_ATTR_FORK);
245 		if (error)
246 			return error;
247 
248 		/* save for re-read later */
249 		child_blkno = XFS_BUF_ADDR(child_bp);
250 
251 		/*
252 		 * Invalidate the subtree, however we have to.
253 		 */
254 		info = child_bp->b_addr;
255 		switch (info->magic) {
256 		case cpu_to_be16(XFS_DA_NODE_MAGIC):
257 		case cpu_to_be16(XFS_DA3_NODE_MAGIC):
258 			error = xfs_attr3_node_inactive(trans, dp, child_bp,
259 							level + 1);
260 			break;
261 		case cpu_to_be16(XFS_ATTR_LEAF_MAGIC):
262 		case cpu_to_be16(XFS_ATTR3_LEAF_MAGIC):
263 			error = xfs_attr3_leaf_inactive(trans, dp, child_bp);
264 			break;
265 		default:
266 			error = -EIO;
267 			xfs_trans_brelse(*trans, child_bp);
268 			break;
269 		}
270 		if (error)
271 			return error;
272 
273 		/*
274 		 * Remove the subsidiary block from the cache and from the log.
275 		 */
276 		error = xfs_da_get_buf(*trans, dp, 0, child_blkno, &child_bp,
277 				       XFS_ATTR_FORK);
278 		if (error)
279 			return error;
280 		xfs_trans_binval(*trans, child_bp);
281 
282 		/*
283 		 * If we're not done, re-read the parent to get the next
284 		 * child block number.
285 		 */
286 		if (i + 1 < ichdr.count) {
287 			error = xfs_da3_node_read(*trans, dp, 0, parent_blkno,
288 						 &bp, XFS_ATTR_FORK);
289 			if (error)
290 				return error;
291 			node = bp->b_addr;
292 			btree = dp->d_ops->node_tree_p(node);
293 			child_fsb = be32_to_cpu(btree[i + 1].before);
294 			xfs_trans_brelse(*trans, bp);
295 		}
296 		/*
297 		 * Atomically commit the whole invalidate stuff.
298 		 */
299 		error = xfs_trans_roll_inode(trans, dp);
300 		if (error)
301 			return  error;
302 	}
303 
304 	return 0;
305 }
306 
307 /*
308  * Indiscriminately delete the entire attribute fork
309  *
310  * Recurse (gasp!) through the attribute nodes until we find leaves.
311  * We're doing a depth-first traversal in order to invalidate everything.
312  */
313 static int
314 xfs_attr3_root_inactive(
315 	struct xfs_trans	**trans,
316 	struct xfs_inode	*dp)
317 {
318 	struct xfs_da_blkinfo	*info;
319 	struct xfs_buf		*bp;
320 	xfs_daddr_t		blkno;
321 	int			error;
322 
323 	/*
324 	 * Read block 0 to see what we have to work with.
325 	 * We only get here if we have extents, since we remove
326 	 * the extents in reverse order the extent containing
327 	 * block 0 must still be there.
328 	 */
329 	error = xfs_da3_node_read(*trans, dp, 0, -1, &bp, XFS_ATTR_FORK);
330 	if (error)
331 		return error;
332 	blkno = bp->b_bn;
333 
334 	/*
335 	 * Invalidate the tree, even if the "tree" is only a single leaf block.
336 	 * This is a depth-first traversal!
337 	 */
338 	info = bp->b_addr;
339 	switch (info->magic) {
340 	case cpu_to_be16(XFS_DA_NODE_MAGIC):
341 	case cpu_to_be16(XFS_DA3_NODE_MAGIC):
342 		error = xfs_attr3_node_inactive(trans, dp, bp, 1);
343 		break;
344 	case cpu_to_be16(XFS_ATTR_LEAF_MAGIC):
345 	case cpu_to_be16(XFS_ATTR3_LEAF_MAGIC):
346 		error = xfs_attr3_leaf_inactive(trans, dp, bp);
347 		break;
348 	default:
349 		error = -EIO;
350 		xfs_trans_brelse(*trans, bp);
351 		break;
352 	}
353 	if (error)
354 		return error;
355 
356 	/*
357 	 * Invalidate the incore copy of the root block.
358 	 */
359 	error = xfs_da_get_buf(*trans, dp, 0, blkno, &bp, XFS_ATTR_FORK);
360 	if (error)
361 		return error;
362 	xfs_trans_binval(*trans, bp);	/* remove from cache */
363 	/*
364 	 * Commit the invalidate and start the next transaction.
365 	 */
366 	error = xfs_trans_roll_inode(trans, dp);
367 
368 	return error;
369 }
370 
371 /*
372  * xfs_attr_inactive kills all traces of an attribute fork on an inode. It
373  * removes both the on-disk and in-memory inode fork. Note that this also has to
374  * handle the condition of inodes without attributes but with an attribute fork
375  * configured, so we can't use xfs_inode_hasattr() here.
376  *
377  * The in-memory attribute fork is removed even on error.
378  */
379 int
380 xfs_attr_inactive(
381 	struct xfs_inode	*dp)
382 {
383 	struct xfs_trans	*trans;
384 	struct xfs_mount	*mp;
385 	int			lock_mode = XFS_ILOCK_SHARED;
386 	int			error = 0;
387 
388 	mp = dp->i_mount;
389 	ASSERT(! XFS_NOT_DQATTACHED(mp, dp));
390 
391 	xfs_ilock(dp, lock_mode);
392 	if (!XFS_IFORK_Q(dp))
393 		goto out_destroy_fork;
394 	xfs_iunlock(dp, lock_mode);
395 
396 	lock_mode = 0;
397 
398 	error = xfs_trans_alloc(mp, &M_RES(mp)->tr_attrinval, 0, 0, 0, &trans);
399 	if (error)
400 		goto out_destroy_fork;
401 
402 	lock_mode = XFS_ILOCK_EXCL;
403 	xfs_ilock(dp, lock_mode);
404 
405 	if (!XFS_IFORK_Q(dp))
406 		goto out_cancel;
407 
408 	/*
409 	 * No need to make quota reservations here. We expect to release some
410 	 * blocks, not allocate, in the common case.
411 	 */
412 	xfs_trans_ijoin(trans, dp, 0);
413 
414 	/*
415 	 * Invalidate and truncate the attribute fork extents. Make sure the
416 	 * fork actually has attributes as otherwise the invalidation has no
417 	 * blocks to read and returns an error. In this case, just do the fork
418 	 * removal below.
419 	 */
420 	if (xfs_inode_hasattr(dp) &&
421 	    dp->i_d.di_aformat != XFS_DINODE_FMT_LOCAL) {
422 		error = xfs_attr3_root_inactive(&trans, dp);
423 		if (error)
424 			goto out_cancel;
425 
426 		error = xfs_itruncate_extents(&trans, dp, XFS_ATTR_FORK, 0);
427 		if (error)
428 			goto out_cancel;
429 	}
430 
431 	/* Reset the attribute fork - this also destroys the in-core fork */
432 	xfs_attr_fork_remove(dp, trans);
433 
434 	error = xfs_trans_commit(trans);
435 	xfs_iunlock(dp, lock_mode);
436 	return error;
437 
438 out_cancel:
439 	xfs_trans_cancel(trans);
440 out_destroy_fork:
441 	/* kill the in-core attr fork before we drop the inode lock */
442 	if (dp->i_afp)
443 		xfs_idestroy_fork(dp, XFS_ATTR_FORK);
444 	if (lock_mode)
445 		xfs_iunlock(dp, lock_mode);
446 	return error;
447 }
448