xref: /openbmc/linux/fs/xfs/xfs_attr_inactive.c (revision f7777dcc)
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_format.h"
22 #include "xfs_bit.h"
23 #include "xfs_log.h"
24 #include "xfs_trans.h"
25 #include "xfs_sb.h"
26 #include "xfs_ag.h"
27 #include "xfs_mount.h"
28 #include "xfs_da_btree.h"
29 #include "xfs_bmap_btree.h"
30 #include "xfs_alloc_btree.h"
31 #include "xfs_ialloc_btree.h"
32 #include "xfs_alloc.h"
33 #include "xfs_btree.h"
34 #include "xfs_attr_remote.h"
35 #include "xfs_dinode.h"
36 #include "xfs_inode.h"
37 #include "xfs_inode_item.h"
38 #include "xfs_bmap.h"
39 #include "xfs_attr.h"
40 #include "xfs_attr_leaf.h"
41 #include "xfs_error.h"
42 #include "xfs_quota.h"
43 #include "xfs_trace.h"
44 #include "xfs_trans_priv.h"
45 
46 /*
47  * Look at all the extents for this logical region,
48  * invalidate any buffers that are incore/in transactions.
49  */
50 STATIC int
51 xfs_attr3_leaf_freextent(
52 	struct xfs_trans	**trans,
53 	struct xfs_inode	*dp,
54 	xfs_dablk_t		blkno,
55 	int			blkcnt)
56 {
57 	struct xfs_bmbt_irec	map;
58 	struct xfs_buf		*bp;
59 	xfs_dablk_t		tblkno;
60 	xfs_daddr_t		dblkno;
61 	int			tblkcnt;
62 	int			dblkcnt;
63 	int			nmap;
64 	int			error;
65 
66 	/*
67 	 * Roll through the "value", invalidating the attribute value's
68 	 * blocks.
69 	 */
70 	tblkno = blkno;
71 	tblkcnt = blkcnt;
72 	while (tblkcnt > 0) {
73 		/*
74 		 * Try to remember where we decided to put the value.
75 		 */
76 		nmap = 1;
77 		error = xfs_bmapi_read(dp, (xfs_fileoff_t)tblkno, tblkcnt,
78 				       &map, &nmap, XFS_BMAPI_ATTRFORK);
79 		if (error) {
80 			return(error);
81 		}
82 		ASSERT(nmap == 1);
83 		ASSERT(map.br_startblock != DELAYSTARTBLOCK);
84 
85 		/*
86 		 * If it's a hole, these are already unmapped
87 		 * so there's nothing to invalidate.
88 		 */
89 		if (map.br_startblock != HOLESTARTBLOCK) {
90 
91 			dblkno = XFS_FSB_TO_DADDR(dp->i_mount,
92 						  map.br_startblock);
93 			dblkcnt = XFS_FSB_TO_BB(dp->i_mount,
94 						map.br_blockcount);
95 			bp = xfs_trans_get_buf(*trans,
96 					dp->i_mount->m_ddev_targp,
97 					dblkno, dblkcnt, 0);
98 			if (!bp)
99 				return ENOMEM;
100 			xfs_trans_binval(*trans, bp);
101 			/*
102 			 * Roll to next transaction.
103 			 */
104 			error = xfs_trans_roll(trans, dp);
105 			if (error)
106 				return (error);
107 		}
108 
109 		tblkno += map.br_blockcount;
110 		tblkcnt -= map.br_blockcount;
111 	}
112 
113 	return(0);
114 }
115 
116 /*
117  * Invalidate all of the "remote" value regions pointed to by a particular
118  * leaf block.
119  * Note that we must release the lock on the buffer so that we are not
120  * caught holding something that the logging code wants to flush to disk.
121  */
122 STATIC int
123 xfs_attr3_leaf_inactive(
124 	struct xfs_trans	**trans,
125 	struct xfs_inode	*dp,
126 	struct xfs_buf		*bp)
127 {
128 	struct xfs_attr_leafblock *leaf;
129 	struct xfs_attr3_icleaf_hdr ichdr;
130 	struct xfs_attr_leaf_entry *entry;
131 	struct xfs_attr_leaf_name_remote *name_rmt;
132 	struct xfs_attr_inactive_list *list;
133 	struct xfs_attr_inactive_list *lp;
134 	int			error;
135 	int			count;
136 	int			size;
137 	int			tmp;
138 	int			i;
139 
140 	leaf = bp->b_addr;
141 	xfs_attr3_leaf_hdr_from_disk(&ichdr, leaf);
142 
143 	/*
144 	 * Count the number of "remote" value extents.
145 	 */
146 	count = 0;
147 	entry = xfs_attr3_leaf_entryp(leaf);
148 	for (i = 0; i < ichdr.count; entry++, i++) {
149 		if (be16_to_cpu(entry->nameidx) &&
150 		    ((entry->flags & XFS_ATTR_LOCAL) == 0)) {
151 			name_rmt = xfs_attr3_leaf_name_remote(leaf, i);
152 			if (name_rmt->valueblk)
153 				count++;
154 		}
155 	}
156 
157 	/*
158 	 * If there are no "remote" values, we're done.
159 	 */
160 	if (count == 0) {
161 		xfs_trans_brelse(*trans, bp);
162 		return 0;
163 	}
164 
165 	/*
166 	 * Allocate storage for a list of all the "remote" value extents.
167 	 */
168 	size = count * sizeof(xfs_attr_inactive_list_t);
169 	list = kmem_alloc(size, KM_SLEEP);
170 
171 	/*
172 	 * Identify each of the "remote" value extents.
173 	 */
174 	lp = list;
175 	entry = xfs_attr3_leaf_entryp(leaf);
176 	for (i = 0; i < ichdr.count; entry++, i++) {
177 		if (be16_to_cpu(entry->nameidx) &&
178 		    ((entry->flags & XFS_ATTR_LOCAL) == 0)) {
179 			name_rmt = xfs_attr3_leaf_name_remote(leaf, i);
180 			if (name_rmt->valueblk) {
181 				lp->valueblk = be32_to_cpu(name_rmt->valueblk);
182 				lp->valuelen = xfs_attr3_rmt_blocks(dp->i_mount,
183 						    be32_to_cpu(name_rmt->valuelen));
184 				lp++;
185 			}
186 		}
187 	}
188 	xfs_trans_brelse(*trans, bp);	/* unlock for trans. in freextent() */
189 
190 	/*
191 	 * Invalidate each of the "remote" value extents.
192 	 */
193 	error = 0;
194 	for (lp = list, i = 0; i < count; i++, lp++) {
195 		tmp = xfs_attr3_leaf_freextent(trans, dp,
196 				lp->valueblk, lp->valuelen);
197 
198 		if (error == 0)
199 			error = tmp;	/* save only the 1st errno */
200 	}
201 
202 	kmem_free(list);
203 	return error;
204 }
205 
206 /*
207  * Recurse (gasp!) through the attribute nodes until we find leaves.
208  * We're doing a depth-first traversal in order to invalidate everything.
209  */
210 STATIC int
211 xfs_attr3_node_inactive(
212 	struct xfs_trans **trans,
213 	struct xfs_inode *dp,
214 	struct xfs_buf	*bp,
215 	int		level)
216 {
217 	xfs_da_blkinfo_t *info;
218 	xfs_da_intnode_t *node;
219 	xfs_dablk_t child_fsb;
220 	xfs_daddr_t parent_blkno, child_blkno;
221 	int error, i;
222 	struct xfs_buf *child_bp;
223 	struct xfs_da_node_entry *btree;
224 	struct xfs_da3_icnode_hdr ichdr;
225 
226 	/*
227 	 * Since this code is recursive (gasp!) we must protect ourselves.
228 	 */
229 	if (level > XFS_DA_NODE_MAXDEPTH) {
230 		xfs_trans_brelse(*trans, bp);	/* no locks for later trans */
231 		return XFS_ERROR(EIO);
232 	}
233 
234 	node = bp->b_addr;
235 	xfs_da3_node_hdr_from_disk(&ichdr, node);
236 	parent_blkno = bp->b_bn;
237 	if (!ichdr.count) {
238 		xfs_trans_brelse(*trans, bp);
239 		return 0;
240 	}
241 	btree = xfs_da3_node_tree_p(node);
242 	child_fsb = be32_to_cpu(btree[0].before);
243 	xfs_trans_brelse(*trans, bp);	/* no locks for later trans */
244 
245 	/*
246 	 * If this is the node level just above the leaves, simply loop
247 	 * over the leaves removing all of them.  If this is higher up
248 	 * in the tree, recurse downward.
249 	 */
250 	for (i = 0; i < ichdr.count; i++) {
251 		/*
252 		 * Read the subsidiary block to see what we have to work with.
253 		 * Don't do this in a transaction.  This is a depth-first
254 		 * traversal of the tree so we may deal with many blocks
255 		 * before we come back to this one.
256 		 */
257 		error = xfs_da3_node_read(*trans, dp, child_fsb, -2, &child_bp,
258 						XFS_ATTR_FORK);
259 		if (error)
260 			return(error);
261 		if (child_bp) {
262 						/* save for re-read later */
263 			child_blkno = XFS_BUF_ADDR(child_bp);
264 
265 			/*
266 			 * Invalidate the subtree, however we have to.
267 			 */
268 			info = child_bp->b_addr;
269 			switch (info->magic) {
270 			case cpu_to_be16(XFS_DA_NODE_MAGIC):
271 			case cpu_to_be16(XFS_DA3_NODE_MAGIC):
272 				error = xfs_attr3_node_inactive(trans, dp,
273 							child_bp, level + 1);
274 				break;
275 			case cpu_to_be16(XFS_ATTR_LEAF_MAGIC):
276 			case cpu_to_be16(XFS_ATTR3_LEAF_MAGIC):
277 				error = xfs_attr3_leaf_inactive(trans, dp,
278 							child_bp);
279 				break;
280 			default:
281 				error = XFS_ERROR(EIO);
282 				xfs_trans_brelse(*trans, child_bp);
283 				break;
284 			}
285 			if (error)
286 				return error;
287 
288 			/*
289 			 * Remove the subsidiary block from the cache
290 			 * and from the log.
291 			 */
292 			error = xfs_da_get_buf(*trans, dp, 0, child_blkno,
293 				&child_bp, XFS_ATTR_FORK);
294 			if (error)
295 				return error;
296 			xfs_trans_binval(*trans, child_bp);
297 		}
298 
299 		/*
300 		 * If we're not done, re-read the parent to get the next
301 		 * child block number.
302 		 */
303 		if (i + 1 < ichdr.count) {
304 			error = xfs_da3_node_read(*trans, dp, 0, parent_blkno,
305 						 &bp, XFS_ATTR_FORK);
306 			if (error)
307 				return error;
308 			child_fsb = be32_to_cpu(btree[i + 1].before);
309 			xfs_trans_brelse(*trans, bp);
310 		}
311 		/*
312 		 * Atomically commit the whole invalidate stuff.
313 		 */
314 		error = xfs_trans_roll(trans, dp);
315 		if (error)
316 			return  error;
317 	}
318 
319 	return 0;
320 }
321 
322 /*
323  * Indiscriminately delete the entire attribute fork
324  *
325  * Recurse (gasp!) through the attribute nodes until we find leaves.
326  * We're doing a depth-first traversal in order to invalidate everything.
327  */
328 int
329 xfs_attr3_root_inactive(
330 	struct xfs_trans	**trans,
331 	struct xfs_inode	*dp)
332 {
333 	struct xfs_da_blkinfo	*info;
334 	struct xfs_buf		*bp;
335 	xfs_daddr_t		blkno;
336 	int			error;
337 
338 	/*
339 	 * Read block 0 to see what we have to work with.
340 	 * We only get here if we have extents, since we remove
341 	 * the extents in reverse order the extent containing
342 	 * block 0 must still be there.
343 	 */
344 	error = xfs_da3_node_read(*trans, dp, 0, -1, &bp, XFS_ATTR_FORK);
345 	if (error)
346 		return error;
347 	blkno = bp->b_bn;
348 
349 	/*
350 	 * Invalidate the tree, even if the "tree" is only a single leaf block.
351 	 * This is a depth-first traversal!
352 	 */
353 	info = bp->b_addr;
354 	switch (info->magic) {
355 	case cpu_to_be16(XFS_DA_NODE_MAGIC):
356 	case cpu_to_be16(XFS_DA3_NODE_MAGIC):
357 		error = xfs_attr3_node_inactive(trans, dp, bp, 1);
358 		break;
359 	case cpu_to_be16(XFS_ATTR_LEAF_MAGIC):
360 	case cpu_to_be16(XFS_ATTR3_LEAF_MAGIC):
361 		error = xfs_attr3_leaf_inactive(trans, dp, bp);
362 		break;
363 	default:
364 		error = XFS_ERROR(EIO);
365 		xfs_trans_brelse(*trans, bp);
366 		break;
367 	}
368 	if (error)
369 		return error;
370 
371 	/*
372 	 * Invalidate the incore copy of the root block.
373 	 */
374 	error = xfs_da_get_buf(*trans, dp, 0, blkno, &bp, XFS_ATTR_FORK);
375 	if (error)
376 		return error;
377 	xfs_trans_binval(*trans, bp);	/* remove from cache */
378 	/*
379 	 * Commit the invalidate and start the next transaction.
380 	 */
381 	error = xfs_trans_roll(trans, dp);
382 
383 	return error;
384 }
385 
386 int
387 xfs_attr_inactive(xfs_inode_t *dp)
388 {
389 	xfs_trans_t *trans;
390 	xfs_mount_t *mp;
391 	int error;
392 
393 	mp = dp->i_mount;
394 	ASSERT(! XFS_NOT_DQATTACHED(mp, dp));
395 
396 	xfs_ilock(dp, XFS_ILOCK_SHARED);
397 	if (!xfs_inode_hasattr(dp) ||
398 	    dp->i_d.di_aformat == XFS_DINODE_FMT_LOCAL) {
399 		xfs_iunlock(dp, XFS_ILOCK_SHARED);
400 		return 0;
401 	}
402 	xfs_iunlock(dp, XFS_ILOCK_SHARED);
403 
404 	/*
405 	 * Start our first transaction of the day.
406 	 *
407 	 * All future transactions during this code must be "chained" off
408 	 * this one via the trans_dup() call.  All transactions will contain
409 	 * the inode, and the inode will always be marked with trans_ihold().
410 	 * Since the inode will be locked in all transactions, we must log
411 	 * the inode in every transaction to let it float upward through
412 	 * the log.
413 	 */
414 	trans = xfs_trans_alloc(mp, XFS_TRANS_ATTRINVAL);
415 	error = xfs_trans_reserve(trans, &M_RES(mp)->tr_attrinval, 0, 0);
416 	if (error) {
417 		xfs_trans_cancel(trans, 0);
418 		return(error);
419 	}
420 	xfs_ilock(dp, XFS_ILOCK_EXCL);
421 
422 	/*
423 	 * No need to make quota reservations here. We expect to release some
424 	 * blocks, not allocate, in the common case.
425 	 */
426 	xfs_trans_ijoin(trans, dp, 0);
427 
428 	/*
429 	 * Decide on what work routines to call based on the inode size.
430 	 */
431 	if (!xfs_inode_hasattr(dp) ||
432 	    dp->i_d.di_aformat == XFS_DINODE_FMT_LOCAL) {
433 		error = 0;
434 		goto out;
435 	}
436 	error = xfs_attr3_root_inactive(&trans, dp);
437 	if (error)
438 		goto out;
439 
440 	error = xfs_itruncate_extents(&trans, dp, XFS_ATTR_FORK, 0);
441 	if (error)
442 		goto out;
443 
444 	error = xfs_trans_commit(trans, XFS_TRANS_RELEASE_LOG_RES);
445 	xfs_iunlock(dp, XFS_ILOCK_EXCL);
446 
447 	return(error);
448 
449 out:
450 	xfs_trans_cancel(trans, XFS_TRANS_RELEASE_LOG_RES|XFS_TRANS_ABORT);
451 	xfs_iunlock(dp, XFS_ILOCK_EXCL);
452 	return(error);
453 }
454