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_mount.h"
27#include "xfs_da_format.h"
28#include "xfs_da_btree.h"
29#include "xfs_inode.h"
30#include "xfs_alloc.h"
31#include "xfs_attr_remote.h"
32#include "xfs_trans.h"
33#include "xfs_inode_item.h"
34#include "xfs_bmap.h"
35#include "xfs_attr.h"
36#include "xfs_attr_leaf.h"
37#include "xfs_error.h"
38#include "xfs_quota.h"
39#include "xfs_trace.h"
40#include "xfs_dir2.h"
41
42/*
43 * Look at all the extents for this logical region,
44 * invalidate any buffers that are incore/in transactions.
45 */
46STATIC int
47xfs_attr3_leaf_freextent(
48	struct xfs_trans	**trans,
49	struct xfs_inode	*dp,
50	xfs_dablk_t		blkno,
51	int			blkcnt)
52{
53	struct xfs_bmbt_irec	map;
54	struct xfs_buf		*bp;
55	xfs_dablk_t		tblkno;
56	xfs_daddr_t		dblkno;
57	int			tblkcnt;
58	int			dblkcnt;
59	int			nmap;
60	int			error;
61
62	/*
63	 * Roll through the "value", invalidating the attribute value's
64	 * blocks.
65	 */
66	tblkno = blkno;
67	tblkcnt = blkcnt;
68	while (tblkcnt > 0) {
69		/*
70		 * Try to remember where we decided to put the value.
71		 */
72		nmap = 1;
73		error = xfs_bmapi_read(dp, (xfs_fileoff_t)tblkno, tblkcnt,
74				       &map, &nmap, XFS_BMAPI_ATTRFORK);
75		if (error) {
76			return error;
77		}
78		ASSERT(nmap == 1);
79		ASSERT(map.br_startblock != DELAYSTARTBLOCK);
80
81		/*
82		 * If it's a hole, these are already unmapped
83		 * so there's nothing to invalidate.
84		 */
85		if (map.br_startblock != HOLESTARTBLOCK) {
86
87			dblkno = XFS_FSB_TO_DADDR(dp->i_mount,
88						  map.br_startblock);
89			dblkcnt = XFS_FSB_TO_BB(dp->i_mount,
90						map.br_blockcount);
91			bp = xfs_trans_get_buf(*trans,
92					dp->i_mount->m_ddev_targp,
93					dblkno, dblkcnt, 0);
94			if (!bp)
95				return -ENOMEM;
96			xfs_trans_binval(*trans, bp);
97			/*
98			 * Roll to next transaction.
99			 */
100			error = xfs_trans_roll(trans, dp);
101			if (error)
102				return error;
103		}
104
105		tblkno += map.br_blockcount;
106		tblkcnt -= map.br_blockcount;
107	}
108
109	return 0;
110}
111
112/*
113 * Invalidate all of the "remote" value regions pointed to by a particular
114 * leaf block.
115 * Note that we must release the lock on the buffer so that we are not
116 * caught holding something that the logging code wants to flush to disk.
117 */
118STATIC int
119xfs_attr3_leaf_inactive(
120	struct xfs_trans	**trans,
121	struct xfs_inode	*dp,
122	struct xfs_buf		*bp)
123{
124	struct xfs_attr_leafblock *leaf;
125	struct xfs_attr3_icleaf_hdr ichdr;
126	struct xfs_attr_leaf_entry *entry;
127	struct xfs_attr_leaf_name_remote *name_rmt;
128	struct xfs_attr_inactive_list *list;
129	struct xfs_attr_inactive_list *lp;
130	int			error;
131	int			count;
132	int			size;
133	int			tmp;
134	int			i;
135	struct xfs_mount	*mp = bp->b_target->bt_mount;
136
137	leaf = bp->b_addr;
138	xfs_attr3_leaf_hdr_from_disk(mp->m_attr_geo, &ichdr, leaf);
139
140	/*
141	 * Count the number of "remote" value extents.
142	 */
143	count = 0;
144	entry = xfs_attr3_leaf_entryp(leaf);
145	for (i = 0; i < ichdr.count; entry++, i++) {
146		if (be16_to_cpu(entry->nameidx) &&
147		    ((entry->flags & XFS_ATTR_LOCAL) == 0)) {
148			name_rmt = xfs_attr3_leaf_name_remote(leaf, i);
149			if (name_rmt->valueblk)
150				count++;
151		}
152	}
153
154	/*
155	 * If there are no "remote" values, we're done.
156	 */
157	if (count == 0) {
158		xfs_trans_brelse(*trans, bp);
159		return 0;
160	}
161
162	/*
163	 * Allocate storage for a list of all the "remote" value extents.
164	 */
165	size = count * sizeof(xfs_attr_inactive_list_t);
166	list = kmem_alloc(size, KM_SLEEP);
167
168	/*
169	 * Identify each of the "remote" value extents.
170	 */
171	lp = list;
172	entry = xfs_attr3_leaf_entryp(leaf);
173	for (i = 0; i < ichdr.count; entry++, i++) {
174		if (be16_to_cpu(entry->nameidx) &&
175		    ((entry->flags & XFS_ATTR_LOCAL) == 0)) {
176			name_rmt = xfs_attr3_leaf_name_remote(leaf, i);
177			if (name_rmt->valueblk) {
178				lp->valueblk = be32_to_cpu(name_rmt->valueblk);
179				lp->valuelen = xfs_attr3_rmt_blocks(dp->i_mount,
180						    be32_to_cpu(name_rmt->valuelen));
181				lp++;
182			}
183		}
184	}
185	xfs_trans_brelse(*trans, bp);	/* unlock for trans. in freextent() */
186
187	/*
188	 * Invalidate each of the "remote" value extents.
189	 */
190	error = 0;
191	for (lp = list, i = 0; i < count; i++, lp++) {
192		tmp = xfs_attr3_leaf_freextent(trans, dp,
193				lp->valueblk, lp->valuelen);
194
195		if (error == 0)
196			error = tmp;	/* save only the 1st errno */
197	}
198
199	kmem_free(list);
200	return error;
201}
202
203/*
204 * Recurse (gasp!) through the attribute nodes until we find leaves.
205 * We're doing a depth-first traversal in order to invalidate everything.
206 */
207STATIC int
208xfs_attr3_node_inactive(
209	struct xfs_trans **trans,
210	struct xfs_inode *dp,
211	struct xfs_buf	*bp,
212	int		level)
213{
214	xfs_da_blkinfo_t *info;
215	xfs_da_intnode_t *node;
216	xfs_dablk_t child_fsb;
217	xfs_daddr_t parent_blkno, child_blkno;
218	int error, i;
219	struct xfs_buf *child_bp;
220	struct xfs_da_node_entry *btree;
221	struct xfs_da3_icnode_hdr ichdr;
222
223	/*
224	 * Since this code is recursive (gasp!) we must protect ourselves.
225	 */
226	if (level > XFS_DA_NODE_MAXDEPTH) {
227		xfs_trans_brelse(*trans, bp);	/* no locks for later trans */
228		return -EIO;
229	}
230
231	node = bp->b_addr;
232	dp->d_ops->node_hdr_from_disk(&ichdr, node);
233	parent_blkno = bp->b_bn;
234	if (!ichdr.count) {
235		xfs_trans_brelse(*trans, bp);
236		return 0;
237	}
238	btree = dp->d_ops->node_tree_p(node);
239	child_fsb = be32_to_cpu(btree[0].before);
240	xfs_trans_brelse(*trans, bp);	/* no locks for later trans */
241
242	/*
243	 * If this is the node level just above the leaves, simply loop
244	 * over the leaves removing all of them.  If this is higher up
245	 * in the tree, recurse downward.
246	 */
247	for (i = 0; i < ichdr.count; i++) {
248		/*
249		 * Read the subsidiary block to see what we have to work with.
250		 * Don't do this in a transaction.  This is a depth-first
251		 * traversal of the tree so we may deal with many blocks
252		 * before we come back to this one.
253		 */
254		error = xfs_da3_node_read(*trans, dp, child_fsb, -2, &child_bp,
255						XFS_ATTR_FORK);
256		if (error)
257			return error;
258		if (child_bp) {
259						/* save for re-read later */
260			child_blkno = XFS_BUF_ADDR(child_bp);
261
262			/*
263			 * Invalidate the subtree, however we have to.
264			 */
265			info = child_bp->b_addr;
266			switch (info->magic) {
267			case cpu_to_be16(XFS_DA_NODE_MAGIC):
268			case cpu_to_be16(XFS_DA3_NODE_MAGIC):
269				error = xfs_attr3_node_inactive(trans, dp,
270							child_bp, level + 1);
271				break;
272			case cpu_to_be16(XFS_ATTR_LEAF_MAGIC):
273			case cpu_to_be16(XFS_ATTR3_LEAF_MAGIC):
274				error = xfs_attr3_leaf_inactive(trans, dp,
275							child_bp);
276				break;
277			default:
278				error = -EIO;
279				xfs_trans_brelse(*trans, child_bp);
280				break;
281			}
282			if (error)
283				return error;
284
285			/*
286			 * Remove the subsidiary block from the cache
287			 * and from the log.
288			 */
289			error = xfs_da_get_buf(*trans, dp, 0, child_blkno,
290				&child_bp, XFS_ATTR_FORK);
291			if (error)
292				return error;
293			xfs_trans_binval(*trans, child_bp);
294		}
295
296		/*
297		 * If we're not done, re-read the parent to get the next
298		 * child block number.
299		 */
300		if (i + 1 < ichdr.count) {
301			error = xfs_da3_node_read(*trans, dp, 0, parent_blkno,
302						 &bp, XFS_ATTR_FORK);
303			if (error)
304				return error;
305			child_fsb = be32_to_cpu(btree[i + 1].before);
306			xfs_trans_brelse(*trans, bp);
307		}
308		/*
309		 * Atomically commit the whole invalidate stuff.
310		 */
311		error = xfs_trans_roll(trans, dp);
312		if (error)
313			return  error;
314	}
315
316	return 0;
317}
318
319/*
320 * Indiscriminately delete the entire attribute fork
321 *
322 * Recurse (gasp!) through the attribute nodes until we find leaves.
323 * We're doing a depth-first traversal in order to invalidate everything.
324 */
325int
326xfs_attr3_root_inactive(
327	struct xfs_trans	**trans,
328	struct xfs_inode	*dp)
329{
330	struct xfs_da_blkinfo	*info;
331	struct xfs_buf		*bp;
332	xfs_daddr_t		blkno;
333	int			error;
334
335	/*
336	 * Read block 0 to see what we have to work with.
337	 * We only get here if we have extents, since we remove
338	 * the extents in reverse order the extent containing
339	 * block 0 must still be there.
340	 */
341	error = xfs_da3_node_read(*trans, dp, 0, -1, &bp, XFS_ATTR_FORK);
342	if (error)
343		return error;
344	blkno = bp->b_bn;
345
346	/*
347	 * Invalidate the tree, even if the "tree" is only a single leaf block.
348	 * This is a depth-first traversal!
349	 */
350	info = bp->b_addr;
351	switch (info->magic) {
352	case cpu_to_be16(XFS_DA_NODE_MAGIC):
353	case cpu_to_be16(XFS_DA3_NODE_MAGIC):
354		error = xfs_attr3_node_inactive(trans, dp, bp, 1);
355		break;
356	case cpu_to_be16(XFS_ATTR_LEAF_MAGIC):
357	case cpu_to_be16(XFS_ATTR3_LEAF_MAGIC):
358		error = xfs_attr3_leaf_inactive(trans, dp, bp);
359		break;
360	default:
361		error = -EIO;
362		xfs_trans_brelse(*trans, bp);
363		break;
364	}
365	if (error)
366		return error;
367
368	/*
369	 * Invalidate the incore copy of the root block.
370	 */
371	error = xfs_da_get_buf(*trans, dp, 0, blkno, &bp, XFS_ATTR_FORK);
372	if (error)
373		return error;
374	xfs_trans_binval(*trans, bp);	/* remove from cache */
375	/*
376	 * Commit the invalidate and start the next transaction.
377	 */
378	error = xfs_trans_roll(trans, dp);
379
380	return error;
381}
382
383/*
384 * xfs_attr_inactive kills all traces of an attribute fork on an inode. It
385 * removes both the on-disk and in-memory inode fork. Note that this also has to
386 * handle the condition of inodes without attributes but with an attribute fork
387 * configured, so we can't use xfs_inode_hasattr() here.
388 *
389 * The in-memory attribute fork is removed even on error.
390 */
391int
392xfs_attr_inactive(
393	struct xfs_inode	*dp)
394{
395	struct xfs_trans	*trans;
396	struct xfs_mount	*mp;
397	int			cancel_flags = 0;
398	int			lock_mode = XFS_ILOCK_SHARED;
399	int			error = 0;
400
401	mp = dp->i_mount;
402	ASSERT(! XFS_NOT_DQATTACHED(mp, dp));
403
404	xfs_ilock(dp, lock_mode);
405	if (!XFS_IFORK_Q(dp))
406		goto out_destroy_fork;
407	xfs_iunlock(dp, lock_mode);
408
409	/*
410	 * Start our first transaction of the day.
411	 *
412	 * All future transactions during this code must be "chained" off
413	 * this one via the trans_dup() call.  All transactions will contain
414	 * the inode, and the inode will always be marked with trans_ihold().
415	 * Since the inode will be locked in all transactions, we must log
416	 * the inode in every transaction to let it float upward through
417	 * the log.
418	 */
419	lock_mode = 0;
420	trans = xfs_trans_alloc(mp, XFS_TRANS_ATTRINVAL);
421	error = xfs_trans_reserve(trans, &M_RES(mp)->tr_attrinval, 0, 0);
422	if (error)
423		goto out_cancel;
424
425	lock_mode = XFS_ILOCK_EXCL;
426	cancel_flags = XFS_TRANS_RELEASE_LOG_RES | XFS_TRANS_ABORT;
427	xfs_ilock(dp, lock_mode);
428
429	if (!XFS_IFORK_Q(dp))
430		goto out_cancel;
431
432	/*
433	 * No need to make quota reservations here. We expect to release some
434	 * blocks, not allocate, in the common case.
435	 */
436	xfs_trans_ijoin(trans, dp, 0);
437
438	/*
439	 * Invalidate and truncate the attribute fork extents. Make sure the
440	 * fork actually has attributes as otherwise the invalidation has no
441	 * blocks to read and returns an error. In this case, just do the fork
442	 * removal below.
443	 */
444	if (xfs_inode_hasattr(dp) &&
445	    dp->i_d.di_aformat != XFS_DINODE_FMT_LOCAL) {
446		error = xfs_attr3_root_inactive(&trans, dp);
447		if (error)
448			goto out_cancel;
449
450		error = xfs_itruncate_extents(&trans, dp, XFS_ATTR_FORK, 0);
451		if (error)
452			goto out_cancel;
453	}
454
455	/* Reset the attribute fork - this also destroys the in-core fork */
456	xfs_attr_fork_remove(dp, trans);
457
458	error = xfs_trans_commit(trans, XFS_TRANS_RELEASE_LOG_RES);
459	xfs_iunlock(dp, lock_mode);
460	return error;
461
462out_cancel:
463	xfs_trans_cancel(trans, cancel_flags);
464out_destroy_fork:
465	/* kill the in-core attr fork before we drop the inode lock */
466	if (dp->i_afp)
467		xfs_idestroy_fork(dp, XFS_ATTR_FORK);
468	if (lock_mode)
469		xfs_iunlock(dp, lock_mode);
470	return error;
471}
472