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_inode(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, -1, &child_bp,
255					  XFS_ATTR_FORK);
256		if (error)
257			return error;
258
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, child_bp,
270							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, child_bp);
275			break;
276		default:
277			error = -EIO;
278			xfs_trans_brelse(*trans, child_bp);
279			break;
280		}
281		if (error)
282			return error;
283
284		/*
285		 * Remove the subsidiary block from the cache and from the log.
286		 */
287		error = xfs_da_get_buf(*trans, dp, 0, child_blkno, &child_bp,
288				       XFS_ATTR_FORK);
289		if (error)
290			return error;
291		xfs_trans_binval(*trans, child_bp);
292
293		/*
294		 * If we're not done, re-read the parent to get the next
295		 * child block number.
296		 */
297		if (i + 1 < ichdr.count) {
298			error = xfs_da3_node_read(*trans, dp, 0, parent_blkno,
299						 &bp, XFS_ATTR_FORK);
300			if (error)
301				return error;
302			node = bp->b_addr;
303			btree = dp->d_ops->node_tree_p(node);
304			child_fsb = be32_to_cpu(btree[i + 1].before);
305			xfs_trans_brelse(*trans, bp);
306		}
307		/*
308		 * Atomically commit the whole invalidate stuff.
309		 */
310		error = xfs_trans_roll_inode(trans, dp);
311		if (error)
312			return  error;
313	}
314
315	return 0;
316}
317
318/*
319 * Indiscriminately delete the entire attribute fork
320 *
321 * Recurse (gasp!) through the attribute nodes until we find leaves.
322 * We're doing a depth-first traversal in order to invalidate everything.
323 */
324static int
325xfs_attr3_root_inactive(
326	struct xfs_trans	**trans,
327	struct xfs_inode	*dp)
328{
329	struct xfs_da_blkinfo	*info;
330	struct xfs_buf		*bp;
331	xfs_daddr_t		blkno;
332	int			error;
333
334	/*
335	 * Read block 0 to see what we have to work with.
336	 * We only get here if we have extents, since we remove
337	 * the extents in reverse order the extent containing
338	 * block 0 must still be there.
339	 */
340	error = xfs_da3_node_read(*trans, dp, 0, -1, &bp, XFS_ATTR_FORK);
341	if (error)
342		return error;
343	blkno = bp->b_bn;
344
345	/*
346	 * Invalidate the tree, even if the "tree" is only a single leaf block.
347	 * This is a depth-first traversal!
348	 */
349	info = bp->b_addr;
350	switch (info->magic) {
351	case cpu_to_be16(XFS_DA_NODE_MAGIC):
352	case cpu_to_be16(XFS_DA3_NODE_MAGIC):
353		error = xfs_attr3_node_inactive(trans, dp, bp, 1);
354		break;
355	case cpu_to_be16(XFS_ATTR_LEAF_MAGIC):
356	case cpu_to_be16(XFS_ATTR3_LEAF_MAGIC):
357		error = xfs_attr3_leaf_inactive(trans, dp, bp);
358		break;
359	default:
360		error = -EIO;
361		xfs_trans_brelse(*trans, bp);
362		break;
363	}
364	if (error)
365		return error;
366
367	/*
368	 * Invalidate the incore copy of the root block.
369	 */
370	error = xfs_da_get_buf(*trans, dp, 0, blkno, &bp, XFS_ATTR_FORK);
371	if (error)
372		return error;
373	xfs_trans_binval(*trans, bp);	/* remove from cache */
374	/*
375	 * Commit the invalidate and start the next transaction.
376	 */
377	error = xfs_trans_roll_inode(trans, dp);
378
379	return error;
380}
381
382/*
383 * xfs_attr_inactive kills all traces of an attribute fork on an inode. It
384 * removes both the on-disk and in-memory inode fork. Note that this also has to
385 * handle the condition of inodes without attributes but with an attribute fork
386 * configured, so we can't use xfs_inode_hasattr() here.
387 *
388 * The in-memory attribute fork is removed even on error.
389 */
390int
391xfs_attr_inactive(
392	struct xfs_inode	*dp)
393{
394	struct xfs_trans	*trans;
395	struct xfs_mount	*mp;
396	int			lock_mode = XFS_ILOCK_SHARED;
397	int			error = 0;
398
399	mp = dp->i_mount;
400	ASSERT(! XFS_NOT_DQATTACHED(mp, dp));
401
402	xfs_ilock(dp, lock_mode);
403	if (!XFS_IFORK_Q(dp))
404		goto out_destroy_fork;
405	xfs_iunlock(dp, lock_mode);
406
407	lock_mode = 0;
408
409	error = xfs_trans_alloc(mp, &M_RES(mp)->tr_attrinval, 0, 0, 0, &trans);
410	if (error)
411		goto out_destroy_fork;
412
413	lock_mode = XFS_ILOCK_EXCL;
414	xfs_ilock(dp, lock_mode);
415
416	if (!XFS_IFORK_Q(dp))
417		goto out_cancel;
418
419	/*
420	 * No need to make quota reservations here. We expect to release some
421	 * blocks, not allocate, in the common case.
422	 */
423	xfs_trans_ijoin(trans, dp, 0);
424
425	/*
426	 * Invalidate and truncate the attribute fork extents. Make sure the
427	 * fork actually has attributes as otherwise the invalidation has no
428	 * blocks to read and returns an error. In this case, just do the fork
429	 * removal below.
430	 */
431	if (xfs_inode_hasattr(dp) &&
432	    dp->i_d.di_aformat != XFS_DINODE_FMT_LOCAL) {
433		error = xfs_attr3_root_inactive(&trans, dp);
434		if (error)
435			goto out_cancel;
436
437		error = xfs_itruncate_extents(&trans, dp, XFS_ATTR_FORK, 0);
438		if (error)
439			goto out_cancel;
440	}
441
442	/* Reset the attribute fork - this also destroys the in-core fork */
443	xfs_attr_fork_remove(dp, trans);
444
445	error = xfs_trans_commit(trans);
446	xfs_iunlock(dp, lock_mode);
447	return error;
448
449out_cancel:
450	xfs_trans_cancel(trans);
451out_destroy_fork:
452	/* kill the in-core attr fork before we drop the inode lock */
453	if (dp->i_afp)
454		xfs_idestroy_fork(dp, XFS_ATTR_FORK);
455	if (lock_mode)
456		xfs_iunlock(dp, lock_mode);
457	return error;
458}