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_attr.h"
 19#include "xfs_attr_remote.h"
 20#include "xfs_trans.h"
 21#include "xfs_bmap.h"
 22#include "xfs_attr_leaf.h"
 23#include "xfs_quota.h"
 24#include "xfs_dir2.h"
 25#include "xfs_error.h"
 26
 27/*
 28 * Invalidate any incore buffers associated with this remote attribute value
 29 * extent.   We never log remote attribute value buffers, which means that they
 30 * won't be attached to a transaction and are therefore safe to mark stale.
 31 * The actual bunmapi will be taken care of later.
 32 */
 33STATIC int
 34xfs_attr3_rmt_stale(
 35	struct xfs_inode	*dp,
 36	xfs_dablk_t		blkno,
 37	int			blkcnt)
 38{
 39	struct xfs_bmbt_irec	map;
 40	int			nmap;
 41	int			error;
 42
 43	/*
 44	 * Roll through the "value", invalidating the attribute value's
 45	 * blocks.
 46	 */
 47	while (blkcnt > 0) {
 48		/*
 49		 * Try to remember where we decided to put the value.
 50		 */
 51		nmap = 1;
 52		error = xfs_bmapi_read(dp, (xfs_fileoff_t)blkno, blkcnt,
 53				       &map, &nmap, XFS_BMAPI_ATTRFORK);
 54		if (error)
 55			return error;
 56		if (XFS_IS_CORRUPT(dp->i_mount, nmap != 1))
 57			return -EFSCORRUPTED;
 58
 59		/*
 60		 * Mark any incore buffers for the remote value as stale.  We
 61		 * never log remote attr value buffers, so the buffer should be
 62		 * easy to kill.
 63		 */
 64		error = xfs_attr_rmtval_stale(dp, &map, 0);
 65		if (error)
 66			return error;
 67
 68		blkno += map.br_blockcount;
 69		blkcnt -= map.br_blockcount;
 70	}
 71
 72	return 0;
 73}
 74
 75/*
 76 * Invalidate all of the "remote" value regions pointed to by a particular
 77 * leaf block.
 78 * Note that we must release the lock on the buffer so that we are not
 79 * caught holding something that the logging code wants to flush to disk.
 80 */
 81STATIC int
 82xfs_attr3_leaf_inactive(
 83	struct xfs_trans		**trans,
 84	struct xfs_inode		*dp,
 85	struct xfs_buf			*bp)
 86{
 87	struct xfs_attr3_icleaf_hdr	ichdr;
 88	struct xfs_mount		*mp = bp->b_mount;
 89	struct xfs_attr_leafblock	*leaf = bp->b_addr;
 90	struct xfs_attr_leaf_entry	*entry;
 91	struct xfs_attr_leaf_name_remote *name_rmt;
 92	int				error = 0;
 93	int				i;
 94
 95	xfs_attr3_leaf_hdr_from_disk(mp->m_attr_geo, &ichdr, leaf);
 96
 97	/*
 98	 * Find the remote value extents for this leaf and invalidate their
 99	 * incore buffers.
100	 */
101	entry = xfs_attr3_leaf_entryp(leaf);
102	for (i = 0; i < ichdr.count; entry++, i++) {
103		int		blkcnt;
104
105		if (!entry->nameidx || (entry->flags & XFS_ATTR_LOCAL))
106			continue;
107
108		name_rmt = xfs_attr3_leaf_name_remote(leaf, i);
109		if (!name_rmt->valueblk)
110			continue;
111
112		blkcnt = xfs_attr3_rmt_blocks(dp->i_mount,
113				be32_to_cpu(name_rmt->valuelen));
114		error = xfs_attr3_rmt_stale(dp,
115				be32_to_cpu(name_rmt->valueblk), blkcnt);
116		if (error)
117			goto err;
118	}
119
120	xfs_trans_brelse(*trans, bp);
121err:
122	return error;
123}
124
125/*
126 * Recurse (gasp!) through the attribute nodes until we find leaves.
127 * We're doing a depth-first traversal in order to invalidate everything.
128 */
129STATIC int
130xfs_attr3_node_inactive(
131	struct xfs_trans	**trans,
132	struct xfs_inode	*dp,
133	struct xfs_buf		*bp,
134	int			level)
135{
136	struct xfs_mount	*mp = dp->i_mount;
137	struct xfs_da_blkinfo	*info;
138	xfs_dablk_t		child_fsb;
139	xfs_daddr_t		parent_blkno, child_blkno;
140	struct xfs_buf		*child_bp;
141	struct xfs_da3_icnode_hdr ichdr;
142	int			error, i;
143
144	/*
145	 * Since this code is recursive (gasp!) we must protect ourselves.
146	 */
147	if (level > XFS_DA_NODE_MAXDEPTH) {
148		xfs_buf_mark_corrupt(bp);
149		xfs_trans_brelse(*trans, bp);	/* no locks for later trans */
150		return -EFSCORRUPTED;
151	}
152
153	xfs_da3_node_hdr_from_disk(dp->i_mount, &ichdr, bp->b_addr);
154	parent_blkno = bp->b_bn;
155	if (!ichdr.count) {
156		xfs_trans_brelse(*trans, bp);
157		return 0;
158	}
159	child_fsb = be32_to_cpu(ichdr.btree[0].before);
160	xfs_trans_brelse(*trans, bp);	/* no locks for later trans */
161
162	/*
163	 * If this is the node level just above the leaves, simply loop
164	 * over the leaves removing all of them.  If this is higher up
165	 * in the tree, recurse downward.
166	 */
167	for (i = 0; i < ichdr.count; i++) {
168		/*
169		 * Read the subsidiary block to see what we have to work with.
170		 * Don't do this in a transaction.  This is a depth-first
171		 * traversal of the tree so we may deal with many blocks
172		 * before we come back to this one.
173		 */
174		error = xfs_da3_node_read(*trans, dp, child_fsb, &child_bp,
175					  XFS_ATTR_FORK);
176		if (error)
177			return error;
178
179		/* save for re-read later */
180		child_blkno = XFS_BUF_ADDR(child_bp);
181
182		/*
183		 * Invalidate the subtree, however we have to.
184		 */
185		info = child_bp->b_addr;
186		switch (info->magic) {
187		case cpu_to_be16(XFS_DA_NODE_MAGIC):
188		case cpu_to_be16(XFS_DA3_NODE_MAGIC):
189			error = xfs_attr3_node_inactive(trans, dp, child_bp,
190							level + 1);
191			break;
192		case cpu_to_be16(XFS_ATTR_LEAF_MAGIC):
193		case cpu_to_be16(XFS_ATTR3_LEAF_MAGIC):
194			error = xfs_attr3_leaf_inactive(trans, dp, child_bp);
195			break;
196		default:
197			xfs_buf_mark_corrupt(child_bp);
198			xfs_trans_brelse(*trans, child_bp);
199			error = -EFSCORRUPTED;
200			break;
201		}
202		if (error)
203			return error;
204
205		/*
206		 * Remove the subsidiary block from the cache and from the log.
207		 */
208		error = xfs_trans_get_buf(*trans, mp->m_ddev_targp,
209				child_blkno,
210				XFS_FSB_TO_BB(mp, mp->m_attr_geo->fsbcount), 0,
211				&child_bp);
212		if (error)
213			return error;
214		error = bp->b_error;
215		if (error) {
216			xfs_trans_brelse(*trans, child_bp);
217			return error;
218		}
219		xfs_trans_binval(*trans, child_bp);
220
221		/*
222		 * If we're not done, re-read the parent to get the next
223		 * child block number.
224		 */
225		if (i + 1 < ichdr.count) {
226			struct xfs_da3_icnode_hdr phdr;
227
228			error = xfs_da3_node_read_mapped(*trans, dp,
229					parent_blkno, &bp, XFS_ATTR_FORK);
230			if (error)
231				return error;
232			xfs_da3_node_hdr_from_disk(dp->i_mount, &phdr,
233						  bp->b_addr);
234			child_fsb = be32_to_cpu(phdr.btree[i + 1].before);
235			xfs_trans_brelse(*trans, bp);
236		}
237		/*
238		 * Atomically commit the whole invalidate stuff.
239		 */
240		error = xfs_trans_roll_inode(trans, dp);
241		if (error)
242			return  error;
243	}
244
245	return 0;
246}
247
248/*
249 * Indiscriminately delete the entire attribute fork
250 *
251 * Recurse (gasp!) through the attribute nodes until we find leaves.
252 * We're doing a depth-first traversal in order to invalidate everything.
253 */
254static int
255xfs_attr3_root_inactive(
256	struct xfs_trans	**trans,
257	struct xfs_inode	*dp)
258{
259	struct xfs_mount	*mp = dp->i_mount;
260	struct xfs_da_blkinfo	*info;
261	struct xfs_buf		*bp;
262	xfs_daddr_t		blkno;
263	int			error;
264
265	/*
266	 * Read block 0 to see what we have to work with.
267	 * We only get here if we have extents, since we remove
268	 * the extents in reverse order the extent containing
269	 * block 0 must still be there.
270	 */
271	error = xfs_da3_node_read(*trans, dp, 0, &bp, XFS_ATTR_FORK);
272	if (error)
273		return error;
274	blkno = bp->b_bn;
275
276	/*
277	 * Invalidate the tree, even if the "tree" is only a single leaf block.
278	 * This is a depth-first traversal!
279	 */
280	info = bp->b_addr;
281	switch (info->magic) {
282	case cpu_to_be16(XFS_DA_NODE_MAGIC):
283	case cpu_to_be16(XFS_DA3_NODE_MAGIC):
284		error = xfs_attr3_node_inactive(trans, dp, bp, 1);
285		break;
286	case cpu_to_be16(XFS_ATTR_LEAF_MAGIC):
287	case cpu_to_be16(XFS_ATTR3_LEAF_MAGIC):
288		error = xfs_attr3_leaf_inactive(trans, dp, bp);
289		break;
290	default:
291		error = -EFSCORRUPTED;
292		xfs_buf_mark_corrupt(bp);
293		xfs_trans_brelse(*trans, bp);
294		break;
295	}
296	if (error)
297		return error;
298
299	/*
300	 * Invalidate the incore copy of the root block.
301	 */
302	error = xfs_trans_get_buf(*trans, mp->m_ddev_targp, blkno,
303			XFS_FSB_TO_BB(mp, mp->m_attr_geo->fsbcount), 0, &bp);
304	if (error)
305		return error;
306	error = bp->b_error;
307	if (error) {
308		xfs_trans_brelse(*trans, bp);
309		return error;
310	}
311	xfs_trans_binval(*trans, bp);	/* remove from cache */
312	/*
313	 * Commit the invalidate and start the next transaction.
314	 */
315	error = xfs_trans_roll_inode(trans, dp);
316
317	return error;
318}
319
320/*
321 * xfs_attr_inactive kills all traces of an attribute fork on an inode. It
322 * removes both the on-disk and in-memory inode fork. Note that this also has to
323 * handle the condition of inodes without attributes but with an attribute fork
324 * configured, so we can't use xfs_inode_hasattr() here.
325 *
326 * The in-memory attribute fork is removed even on error.
327 */
328int
329xfs_attr_inactive(
330	struct xfs_inode	*dp)
331{
332	struct xfs_trans	*trans;
333	struct xfs_mount	*mp;
334	int			lock_mode = XFS_ILOCK_SHARED;
335	int			error = 0;
336
337	mp = dp->i_mount;
338	ASSERT(! XFS_NOT_DQATTACHED(mp, dp));
339
340	xfs_ilock(dp, lock_mode);
341	if (!XFS_IFORK_Q(dp))
342		goto out_destroy_fork;
343	xfs_iunlock(dp, lock_mode);
344
345	lock_mode = 0;
346
347	error = xfs_trans_alloc(mp, &M_RES(mp)->tr_attrinval, 0, 0, 0, &trans);
348	if (error)
349		goto out_destroy_fork;
350
351	lock_mode = XFS_ILOCK_EXCL;
352	xfs_ilock(dp, lock_mode);
353
354	if (!XFS_IFORK_Q(dp))
355		goto out_cancel;
356
357	/*
358	 * No need to make quota reservations here. We expect to release some
359	 * blocks, not allocate, in the common case.
360	 */
361	xfs_trans_ijoin(trans, dp, 0);
362
363	/*
364	 * Invalidate and truncate the attribute fork extents. Make sure the
365	 * fork actually has attributes as otherwise the invalidation has no
366	 * blocks to read and returns an error. In this case, just do the fork
367	 * removal below.
368	 */
369	if (xfs_inode_hasattr(dp) &&
370	    dp->i_afp->if_format != XFS_DINODE_FMT_LOCAL) {
371		error = xfs_attr3_root_inactive(&trans, dp);
372		if (error)
373			goto out_cancel;
374
375		error = xfs_itruncate_extents(&trans, dp, XFS_ATTR_FORK, 0);
376		if (error)
377			goto out_cancel;
378	}
379
380	/* Reset the attribute fork - this also destroys the in-core fork */
381	xfs_attr_fork_remove(dp, trans);
382
383	error = xfs_trans_commit(trans);
384	xfs_iunlock(dp, lock_mode);
385	return error;
386
387out_cancel:
388	xfs_trans_cancel(trans);
389out_destroy_fork:
390	/* kill the in-core attr fork before we drop the inode lock */
391	if (dp->i_afp) {
392		xfs_idestroy_fork(dp->i_afp);
393		kmem_cache_free(xfs_ifork_zone, dp->i_afp);
394		dp->i_afp = NULL;
395	}
396	if (lock_mode)
397		xfs_iunlock(dp, lock_mode);
398	return error;
399}