xref: /openbmc/linux/fs/xfs/xfs_attr_inactive.c (revision e917ba44)
1 /*
2  * Copyright (c) 2000-2005 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_bit.h"
26 #include "xfs_sb.h"
27 #include "xfs_ag.h"
28 #include "xfs_mount.h"
29 #include "xfs_da_format.h"
30 #include "xfs_da_btree.h"
31 #include "xfs_inode.h"
32 #include "xfs_alloc.h"
33 #include "xfs_attr_remote.h"
34 #include "xfs_trans.h"
35 #include "xfs_inode_item.h"
36 #include "xfs_bmap.h"
37 #include "xfs_attr.h"
38 #include "xfs_attr_leaf.h"
39 #include "xfs_error.h"
40 #include "xfs_quota.h"
41 #include "xfs_trace.h"
42 #include "xfs_dinode.h"
43 #include "xfs_dir2.h"
44 
45 /*
46  * Look at all the extents for this logical region,
47  * invalidate any buffers that are incore/in transactions.
48  */
49 STATIC int
50 xfs_attr3_leaf_freextent(
51 	struct xfs_trans	**trans,
52 	struct xfs_inode	*dp,
53 	xfs_dablk_t		blkno,
54 	int			blkcnt)
55 {
56 	struct xfs_bmbt_irec	map;
57 	struct xfs_buf		*bp;
58 	xfs_dablk_t		tblkno;
59 	xfs_daddr_t		dblkno;
60 	int			tblkcnt;
61 	int			dblkcnt;
62 	int			nmap;
63 	int			error;
64 
65 	/*
66 	 * Roll through the "value", invalidating the attribute value's
67 	 * blocks.
68 	 */
69 	tblkno = blkno;
70 	tblkcnt = blkcnt;
71 	while (tblkcnt > 0) {
72 		/*
73 		 * Try to remember where we decided to put the value.
74 		 */
75 		nmap = 1;
76 		error = xfs_bmapi_read(dp, (xfs_fileoff_t)tblkno, tblkcnt,
77 				       &map, &nmap, XFS_BMAPI_ATTRFORK);
78 		if (error) {
79 			return error;
80 		}
81 		ASSERT(nmap == 1);
82 		ASSERT(map.br_startblock != DELAYSTARTBLOCK);
83 
84 		/*
85 		 * If it's a hole, these are already unmapped
86 		 * so there's nothing to invalidate.
87 		 */
88 		if (map.br_startblock != HOLESTARTBLOCK) {
89 
90 			dblkno = XFS_FSB_TO_DADDR(dp->i_mount,
91 						  map.br_startblock);
92 			dblkcnt = XFS_FSB_TO_BB(dp->i_mount,
93 						map.br_blockcount);
94 			bp = xfs_trans_get_buf(*trans,
95 					dp->i_mount->m_ddev_targp,
96 					dblkno, dblkcnt, 0);
97 			if (!bp)
98 				return -ENOMEM;
99 			xfs_trans_binval(*trans, bp);
100 			/*
101 			 * Roll to next transaction.
102 			 */
103 			error = xfs_trans_roll(trans, dp);
104 			if (error)
105 				return error;
106 		}
107 
108 		tblkno += map.br_blockcount;
109 		tblkcnt -= map.br_blockcount;
110 	}
111 
112 	return 0;
113 }
114 
115 /*
116  * Invalidate all of the "remote" value regions pointed to by a particular
117  * leaf block.
118  * Note that we must release the lock on the buffer so that we are not
119  * caught holding something that the logging code wants to flush to disk.
120  */
121 STATIC int
122 xfs_attr3_leaf_inactive(
123 	struct xfs_trans	**trans,
124 	struct xfs_inode	*dp,
125 	struct xfs_buf		*bp)
126 {
127 	struct xfs_attr_leafblock *leaf;
128 	struct xfs_attr3_icleaf_hdr ichdr;
129 	struct xfs_attr_leaf_entry *entry;
130 	struct xfs_attr_leaf_name_remote *name_rmt;
131 	struct xfs_attr_inactive_list *list;
132 	struct xfs_attr_inactive_list *lp;
133 	int			error;
134 	int			count;
135 	int			size;
136 	int			tmp;
137 	int			i;
138 
139 	leaf = bp->b_addr;
140 	xfs_attr3_leaf_hdr_from_disk(&ichdr, leaf);
141 
142 	/*
143 	 * Count the number of "remote" value extents.
144 	 */
145 	count = 0;
146 	entry = xfs_attr3_leaf_entryp(leaf);
147 	for (i = 0; i < ichdr.count; entry++, i++) {
148 		if (be16_to_cpu(entry->nameidx) &&
149 		    ((entry->flags & XFS_ATTR_LOCAL) == 0)) {
150 			name_rmt = xfs_attr3_leaf_name_remote(leaf, i);
151 			if (name_rmt->valueblk)
152 				count++;
153 		}
154 	}
155 
156 	/*
157 	 * If there are no "remote" values, we're done.
158 	 */
159 	if (count == 0) {
160 		xfs_trans_brelse(*trans, bp);
161 		return 0;
162 	}
163 
164 	/*
165 	 * Allocate storage for a list of all the "remote" value extents.
166 	 */
167 	size = count * sizeof(xfs_attr_inactive_list_t);
168 	list = kmem_alloc(size, KM_SLEEP);
169 
170 	/*
171 	 * Identify each of the "remote" value extents.
172 	 */
173 	lp = list;
174 	entry = xfs_attr3_leaf_entryp(leaf);
175 	for (i = 0; i < ichdr.count; entry++, i++) {
176 		if (be16_to_cpu(entry->nameidx) &&
177 		    ((entry->flags & XFS_ATTR_LOCAL) == 0)) {
178 			name_rmt = xfs_attr3_leaf_name_remote(leaf, i);
179 			if (name_rmt->valueblk) {
180 				lp->valueblk = be32_to_cpu(name_rmt->valueblk);
181 				lp->valuelen = xfs_attr3_rmt_blocks(dp->i_mount,
182 						    be32_to_cpu(name_rmt->valuelen));
183 				lp++;
184 			}
185 		}
186 	}
187 	xfs_trans_brelse(*trans, bp);	/* unlock for trans. in freextent() */
188 
189 	/*
190 	 * Invalidate each of the "remote" value extents.
191 	 */
192 	error = 0;
193 	for (lp = list, i = 0; i < count; i++, lp++) {
194 		tmp = xfs_attr3_leaf_freextent(trans, dp,
195 				lp->valueblk, lp->valuelen);
196 
197 		if (error == 0)
198 			error = tmp;	/* save only the 1st errno */
199 	}
200 
201 	kmem_free(list);
202 	return error;
203 }
204 
205 /*
206  * Recurse (gasp!) through the attribute nodes until we find leaves.
207  * We're doing a depth-first traversal in order to invalidate everything.
208  */
209 STATIC int
210 xfs_attr3_node_inactive(
211 	struct xfs_trans **trans,
212 	struct xfs_inode *dp,
213 	struct xfs_buf	*bp,
214 	int		level)
215 {
216 	xfs_da_blkinfo_t *info;
217 	xfs_da_intnode_t *node;
218 	xfs_dablk_t child_fsb;
219 	xfs_daddr_t parent_blkno, child_blkno;
220 	int error, i;
221 	struct xfs_buf *child_bp;
222 	struct xfs_da_node_entry *btree;
223 	struct xfs_da3_icnode_hdr ichdr;
224 
225 	/*
226 	 * Since this code is recursive (gasp!) we must protect ourselves.
227 	 */
228 	if (level > XFS_DA_NODE_MAXDEPTH) {
229 		xfs_trans_brelse(*trans, bp);	/* no locks for later trans */
230 		return -EIO;
231 	}
232 
233 	node = bp->b_addr;
234 	dp->d_ops->node_hdr_from_disk(&ichdr, node);
235 	parent_blkno = bp->b_bn;
236 	if (!ichdr.count) {
237 		xfs_trans_brelse(*trans, bp);
238 		return 0;
239 	}
240 	btree = dp->d_ops->node_tree_p(node);
241 	child_fsb = be32_to_cpu(btree[0].before);
242 	xfs_trans_brelse(*trans, bp);	/* no locks for later trans */
243 
244 	/*
245 	 * If this is the node level just above the leaves, simply loop
246 	 * over the leaves removing all of them.  If this is higher up
247 	 * in the tree, recurse downward.
248 	 */
249 	for (i = 0; i < ichdr.count; i++) {
250 		/*
251 		 * Read the subsidiary block to see what we have to work with.
252 		 * Don't do this in a transaction.  This is a depth-first
253 		 * traversal of the tree so we may deal with many blocks
254 		 * before we come back to this one.
255 		 */
256 		error = xfs_da3_node_read(*trans, dp, child_fsb, -2, &child_bp,
257 						XFS_ATTR_FORK);
258 		if (error)
259 			return error;
260 		if (child_bp) {
261 						/* save for re-read later */
262 			child_blkno = XFS_BUF_ADDR(child_bp);
263 
264 			/*
265 			 * Invalidate the subtree, however we have to.
266 			 */
267 			info = child_bp->b_addr;
268 			switch (info->magic) {
269 			case cpu_to_be16(XFS_DA_NODE_MAGIC):
270 			case cpu_to_be16(XFS_DA3_NODE_MAGIC):
271 				error = xfs_attr3_node_inactive(trans, dp,
272 							child_bp, level + 1);
273 				break;
274 			case cpu_to_be16(XFS_ATTR_LEAF_MAGIC):
275 			case cpu_to_be16(XFS_ATTR3_LEAF_MAGIC):
276 				error = xfs_attr3_leaf_inactive(trans, dp,
277 							child_bp);
278 				break;
279 			default:
280 				error = -EIO;
281 				xfs_trans_brelse(*trans, child_bp);
282 				break;
283 			}
284 			if (error)
285 				return error;
286 
287 			/*
288 			 * Remove the subsidiary block from the cache
289 			 * and from the log.
290 			 */
291 			error = xfs_da_get_buf(*trans, dp, 0, child_blkno,
292 				&child_bp, XFS_ATTR_FORK);
293 			if (error)
294 				return error;
295 			xfs_trans_binval(*trans, child_bp);
296 		}
297 
298 		/*
299 		 * If we're not done, re-read the parent to get the next
300 		 * child block number.
301 		 */
302 		if (i + 1 < ichdr.count) {
303 			error = xfs_da3_node_read(*trans, dp, 0, parent_blkno,
304 						 &bp, XFS_ATTR_FORK);
305 			if (error)
306 				return error;
307 			child_fsb = be32_to_cpu(btree[i + 1].before);
308 			xfs_trans_brelse(*trans, bp);
309 		}
310 		/*
311 		 * Atomically commit the whole invalidate stuff.
312 		 */
313 		error = xfs_trans_roll(trans, dp);
314 		if (error)
315 			return  error;
316 	}
317 
318 	return 0;
319 }
320 
321 /*
322  * Indiscriminately delete the entire attribute fork
323  *
324  * Recurse (gasp!) through the attribute nodes until we find leaves.
325  * We're doing a depth-first traversal in order to invalidate everything.
326  */
327 int
328 xfs_attr3_root_inactive(
329 	struct xfs_trans	**trans,
330 	struct xfs_inode	*dp)
331 {
332 	struct xfs_da_blkinfo	*info;
333 	struct xfs_buf		*bp;
334 	xfs_daddr_t		blkno;
335 	int			error;
336 
337 	/*
338 	 * Read block 0 to see what we have to work with.
339 	 * We only get here if we have extents, since we remove
340 	 * the extents in reverse order the extent containing
341 	 * block 0 must still be there.
342 	 */
343 	error = xfs_da3_node_read(*trans, dp, 0, -1, &bp, XFS_ATTR_FORK);
344 	if (error)
345 		return error;
346 	blkno = bp->b_bn;
347 
348 	/*
349 	 * Invalidate the tree, even if the "tree" is only a single leaf block.
350 	 * This is a depth-first traversal!
351 	 */
352 	info = bp->b_addr;
353 	switch (info->magic) {
354 	case cpu_to_be16(XFS_DA_NODE_MAGIC):
355 	case cpu_to_be16(XFS_DA3_NODE_MAGIC):
356 		error = xfs_attr3_node_inactive(trans, dp, bp, 1);
357 		break;
358 	case cpu_to_be16(XFS_ATTR_LEAF_MAGIC):
359 	case cpu_to_be16(XFS_ATTR3_LEAF_MAGIC):
360 		error = xfs_attr3_leaf_inactive(trans, dp, bp);
361 		break;
362 	default:
363 		error = -EIO;
364 		xfs_trans_brelse(*trans, bp);
365 		break;
366 	}
367 	if (error)
368 		return error;
369 
370 	/*
371 	 * Invalidate the incore copy of the root block.
372 	 */
373 	error = xfs_da_get_buf(*trans, dp, 0, blkno, &bp, XFS_ATTR_FORK);
374 	if (error)
375 		return error;
376 	xfs_trans_binval(*trans, bp);	/* remove from cache */
377 	/*
378 	 * Commit the invalidate and start the next transaction.
379 	 */
380 	error = xfs_trans_roll(trans, dp);
381 
382 	return error;
383 }
384 
385 int
386 xfs_attr_inactive(xfs_inode_t *dp)
387 {
388 	xfs_trans_t *trans;
389 	xfs_mount_t *mp;
390 	int error;
391 
392 	mp = dp->i_mount;
393 	ASSERT(! XFS_NOT_DQATTACHED(mp, dp));
394 
395 	xfs_ilock(dp, XFS_ILOCK_SHARED);
396 	if (!xfs_inode_hasattr(dp) ||
397 	    dp->i_d.di_aformat == XFS_DINODE_FMT_LOCAL) {
398 		xfs_iunlock(dp, XFS_ILOCK_SHARED);
399 		return 0;
400 	}
401 	xfs_iunlock(dp, XFS_ILOCK_SHARED);
402 
403 	/*
404 	 * Start our first transaction of the day.
405 	 *
406 	 * All future transactions during this code must be "chained" off
407 	 * this one via the trans_dup() call.  All transactions will contain
408 	 * the inode, and the inode will always be marked with trans_ihold().
409 	 * Since the inode will be locked in all transactions, we must log
410 	 * the inode in every transaction to let it float upward through
411 	 * the log.
412 	 */
413 	trans = xfs_trans_alloc(mp, XFS_TRANS_ATTRINVAL);
414 	error = xfs_trans_reserve(trans, &M_RES(mp)->tr_attrinval, 0, 0);
415 	if (error) {
416 		xfs_trans_cancel(trans, 0);
417 		return error;
418 	}
419 	xfs_ilock(dp, XFS_ILOCK_EXCL);
420 
421 	/*
422 	 * No need to make quota reservations here. We expect to release some
423 	 * blocks, not allocate, in the common case.
424 	 */
425 	xfs_trans_ijoin(trans, dp, 0);
426 
427 	/*
428 	 * Decide on what work routines to call based on the inode size.
429 	 */
430 	if (!xfs_inode_hasattr(dp) ||
431 	    dp->i_d.di_aformat == XFS_DINODE_FMT_LOCAL) {
432 		error = 0;
433 		goto out;
434 	}
435 	error = xfs_attr3_root_inactive(&trans, dp);
436 	if (error)
437 		goto out;
438 
439 	error = xfs_itruncate_extents(&trans, dp, XFS_ATTR_FORK, 0);
440 	if (error)
441 		goto out;
442 
443 	error = xfs_trans_commit(trans, XFS_TRANS_RELEASE_LOG_RES);
444 	xfs_iunlock(dp, XFS_ILOCK_EXCL);
445 
446 	return error;
447 
448 out:
449 	xfs_trans_cancel(trans, XFS_TRANS_RELEASE_LOG_RES|XFS_TRANS_ABORT);
450 	xfs_iunlock(dp, XFS_ILOCK_EXCL);
451 	return error;
452 }
453