diff options
Diffstat (limited to 'fs/xfs/scrub/attr_repair.c')
| -rw-r--r-- | fs/xfs/scrub/attr_repair.c | 1663 |
1 files changed, 1663 insertions, 0 deletions
diff --git a/fs/xfs/scrub/attr_repair.c b/fs/xfs/scrub/attr_repair.c new file mode 100644 index 000000000000..c7eb94069caf --- /dev/null +++ b/fs/xfs/scrub/attr_repair.c @@ -0,0 +1,1663 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (c) 2018-2024 Oracle. All Rights Reserved. + * Author: Darrick J. Wong <djwong@kernel.org> + */ +#include "xfs.h" +#include "xfs_fs.h" +#include "xfs_shared.h" +#include "xfs_format.h" +#include "xfs_trans_resv.h" +#include "xfs_mount.h" +#include "xfs_defer.h" +#include "xfs_btree.h" +#include "xfs_bit.h" +#include "xfs_log_format.h" +#include "xfs_trans.h" +#include "xfs_sb.h" +#include "xfs_inode.h" +#include "xfs_da_format.h" +#include "xfs_da_btree.h" +#include "xfs_dir2.h" +#include "xfs_attr.h" +#include "xfs_attr_leaf.h" +#include "xfs_attr_sf.h" +#include "xfs_attr_remote.h" +#include "xfs_bmap.h" +#include "xfs_bmap_util.h" +#include "xfs_exchmaps.h" +#include "xfs_exchrange.h" +#include "xfs_acl.h" +#include "xfs_parent.h" +#include "scrub/xfs_scrub.h" +#include "scrub/scrub.h" +#include "scrub/common.h" +#include "scrub/trace.h" +#include "scrub/repair.h" +#include "scrub/tempfile.h" +#include "scrub/tempexch.h" +#include "scrub/xfile.h" +#include "scrub/xfarray.h" +#include "scrub/xfblob.h" +#include "scrub/attr.h" +#include "scrub/reap.h" +#include "scrub/attr_repair.h" + +/* + * Extended Attribute Repair + * ========================= + * + * We repair extended attributes by reading the attr leaf blocks looking for + * attributes entries that look salvageable (name passes verifiers, value can + * be retrieved, etc). Each extended attribute worth salvaging is stashed in + * memory, and the stashed entries are periodically replayed into a temporary + * file to constrain memory use. Batching the construction of the temporary + * extended attribute structure in this fashion reduces lock cycling of the + * file being repaired and the temporary file. + * + * When salvaging completes, the remaining stashed attributes are replayed to + * the temporary file. An atomic file contents exchange is used to commit the + * new xattr blocks to the file being repaired. This will disrupt attrmulti + * cursors. + */ + +struct xrep_xattr_key { + /* Cookie for retrieval of the xattr name. */ + xfblob_cookie name_cookie; + + /* Cookie for retrieval of the xattr value. */ + xfblob_cookie value_cookie; + + /* XFS_ATTR_* flags */ + int flags; + + /* Length of the value and name. */ + uint32_t valuelen; + uint16_t namelen; +}; + +/* + * Stash up to 8 pages of attrs in xattr_records/xattr_blobs before we write + * them to the temp file. + */ +#define XREP_XATTR_MAX_STASH_BYTES (PAGE_SIZE * 8) + +struct xrep_xattr { + struct xfs_scrub *sc; + + /* Information for exchanging attr fork mappings at the end. */ + struct xrep_tempexch tx; + + /* xattr keys */ + struct xfarray *xattr_records; + + /* xattr values */ + struct xfblob *xattr_blobs; + + /* Number of attributes that we are salvaging. */ + unsigned long long attrs_found; + + /* Can we flush stashed attrs to the tempfile? */ + bool can_flush; + + /* Did the live update fail, and hence the repair is now out of date? */ + bool live_update_aborted; + + /* Lock protecting parent pointer updates */ + struct mutex lock; + + /* Fixed-size array of xrep_xattr_pptr structures. */ + struct xfarray *pptr_recs; + + /* Blobs containing parent pointer names. */ + struct xfblob *pptr_names; + + /* Hook to capture parent pointer updates. */ + struct xfs_dir_hook dhook; + + /* Scratch buffer for capturing parent pointers. */ + struct xfs_da_args pptr_args; + + /* Name buffer */ + struct xfs_name xname; + char namebuf[MAXNAMELEN]; +}; + +/* Create a parent pointer in the tempfile. */ +#define XREP_XATTR_PPTR_ADD (1) + +/* Remove a parent pointer from the tempfile. */ +#define XREP_XATTR_PPTR_REMOVE (2) + +/* A stashed parent pointer update. */ +struct xrep_xattr_pptr { + /* Cookie for retrieval of the pptr name. */ + xfblob_cookie name_cookie; + + /* Parent pointer record. */ + struct xfs_parent_rec pptr_rec; + + /* Length of the pptr name. */ + uint8_t namelen; + + /* XREP_XATTR_PPTR_{ADD,REMOVE} */ + uint8_t action; +}; + +/* Set up to recreate the extended attributes. */ +int +xrep_setup_xattr( + struct xfs_scrub *sc) +{ + if (xfs_has_parent(sc->mp)) + xchk_fsgates_enable(sc, XCHK_FSGATES_DIRENTS); + + return xrep_tempfile_create(sc, S_IFREG); +} + +/* + * Decide if we want to salvage this attribute. We don't bother with + * incomplete or oversized keys or values. The @value parameter can be null + * for remote attrs. + */ +STATIC int +xrep_xattr_want_salvage( + struct xrep_xattr *rx, + unsigned int attr_flags, + const void *name, + int namelen, + const void *value, + int valuelen) +{ + if (attr_flags & XFS_ATTR_INCOMPLETE) + return false; + if (namelen > XATTR_NAME_MAX || namelen <= 0) + return false; + if (!xfs_attr_namecheck(attr_flags, name, namelen)) + return false; + if (valuelen > XATTR_SIZE_MAX || valuelen < 0) + return false; + if (attr_flags & XFS_ATTR_PARENT) + return xfs_parent_valuecheck(rx->sc->mp, value, valuelen); + + return true; +} + +/* Allocate an in-core record to hold xattrs while we rebuild the xattr data. */ +STATIC int +xrep_xattr_salvage_key( + struct xrep_xattr *rx, + int flags, + unsigned char *name, + int namelen, + unsigned char *value, + int valuelen) +{ + struct xrep_xattr_key key = { + .valuelen = valuelen, + .flags = flags & XFS_ATTR_NSP_ONDISK_MASK, + }; + unsigned int i = 0; + int error = 0; + + if (xchk_should_terminate(rx->sc, &error)) + return error; + + /* + * Truncate the name to the first character that would trip namecheck. + * If we no longer have a name after that, ignore this attribute. + */ + if (flags & XFS_ATTR_PARENT) { + key.namelen = namelen; + + trace_xrep_xattr_salvage_pptr(rx->sc->ip, flags, name, + key.namelen, value, valuelen); + } else { + while (i < namelen && name[i] != 0) + i++; + if (i == 0) + return 0; + key.namelen = i; + + trace_xrep_xattr_salvage_rec(rx->sc->ip, flags, name, + key.namelen, valuelen); + } + + error = xfblob_store(rx->xattr_blobs, &key.name_cookie, name, + key.namelen); + if (error) + return error; + + error = xfblob_store(rx->xattr_blobs, &key.value_cookie, value, + key.valuelen); + if (error) + return error; + + error = xfarray_append(rx->xattr_records, &key); + if (error) + return error; + + rx->attrs_found++; + return 0; +} + +/* + * Record a shortform extended attribute key & value for later reinsertion + * into the inode. + */ +STATIC int +xrep_xattr_salvage_sf_attr( + struct xrep_xattr *rx, + struct xfs_attr_sf_hdr *hdr, + struct xfs_attr_sf_entry *sfe) +{ + struct xfs_scrub *sc = rx->sc; + struct xchk_xattr_buf *ab = sc->buf; + unsigned char *name = sfe->nameval; + unsigned char *value = &sfe->nameval[sfe->namelen]; + + if (!xchk_xattr_set_map(sc, ab->usedmap, (char *)name - (char *)hdr, + sfe->namelen)) + return 0; + + if (!xchk_xattr_set_map(sc, ab->usedmap, (char *)value - (char *)hdr, + sfe->valuelen)) + return 0; + + if (!xrep_xattr_want_salvage(rx, sfe->flags, sfe->nameval, + sfe->namelen, value, sfe->valuelen)) + return 0; + + return xrep_xattr_salvage_key(rx, sfe->flags, sfe->nameval, + sfe->namelen, value, sfe->valuelen); +} + +/* + * Record a local format extended attribute key & value for later reinsertion + * into the inode. + */ +STATIC int +xrep_xattr_salvage_local_attr( + struct xrep_xattr *rx, + struct xfs_attr_leaf_entry *ent, + unsigned int nameidx, + const char *buf_end, + struct xfs_attr_leaf_name_local *lentry) +{ + struct xchk_xattr_buf *ab = rx->sc->buf; + unsigned char *value; + unsigned int valuelen; + unsigned int namesize; + + /* + * Decode the leaf local entry format. If something seems wrong, we + * junk the attribute. + */ + value = &lentry->nameval[lentry->namelen]; + valuelen = be16_to_cpu(lentry->valuelen); + namesize = xfs_attr_leaf_entsize_local(lentry->namelen, valuelen); + if ((char *)lentry + namesize > buf_end) + return 0; + if (!xrep_xattr_want_salvage(rx, ent->flags, lentry->nameval, + lentry->namelen, value, valuelen)) + return 0; + if (!xchk_xattr_set_map(rx->sc, ab->usedmap, nameidx, namesize)) + return 0; + + /* Try to save this attribute. */ + return xrep_xattr_salvage_key(rx, ent->flags, lentry->nameval, + lentry->namelen, value, valuelen); +} + +/* + * Record a remote format extended attribute key & value for later reinsertion + * into the inode. + */ +STATIC int +xrep_xattr_salvage_remote_attr( + struct xrep_xattr *rx, + struct xfs_attr_leaf_entry *ent, + unsigned int nameidx, + const char *buf_end, + struct xfs_attr_leaf_name_remote *rentry, + unsigned int ent_idx, + struct xfs_buf *leaf_bp) +{ + struct xchk_xattr_buf *ab = rx->sc->buf; + struct xfs_da_args args = { + .trans = rx->sc->tp, + .dp = rx->sc->ip, + .index = ent_idx, + .geo = rx->sc->mp->m_attr_geo, + .owner = rx->sc->ip->i_ino, + .attr_filter = ent->flags & XFS_ATTR_NSP_ONDISK_MASK, + .namelen = rentry->namelen, + .name = rentry->name, + .value = ab->value, + .valuelen = be32_to_cpu(rentry->valuelen), + }; + unsigned int namesize; + int error; + + /* + * Decode the leaf remote entry format. If something seems wrong, we + * junk the attribute. Note that we should never find a zero-length + * remote attribute value. + */ + namesize = xfs_attr_leaf_entsize_remote(rentry->namelen); + if ((char *)rentry + namesize > buf_end) + return 0; + if (args.valuelen == 0 || + !xrep_xattr_want_salvage(rx, ent->flags, rentry->name, + rentry->namelen, NULL, args.valuelen)) + return 0; + if (!xchk_xattr_set_map(rx->sc, ab->usedmap, nameidx, namesize)) + return 0; + + /* + * Enlarge the buffer (if needed) to hold the value that we're trying + * to salvage from the old extended attribute data. + */ + error = xchk_setup_xattr_buf(rx->sc, args.valuelen); + if (error == -ENOMEM) + error = -EDEADLOCK; + if (error) + return error; + + /* Look up the remote value and stash it for reconstruction. */ + error = xfs_attr3_leaf_getvalue(leaf_bp, &args); + if (error || args.rmtblkno == 0) + goto err_free; + + error = xfs_attr_rmtval_get(&args); + if (error) + goto err_free; + + /* Try to save this attribute. */ + error = xrep_xattr_salvage_key(rx, ent->flags, rentry->name, + rentry->namelen, ab->value, args.valuelen); +err_free: + /* remote value was garbage, junk it */ + if (error == -EFSBADCRC || error == -EFSCORRUPTED) + error = 0; + return error; +} + +/* Extract every xattr key that we can from this attr fork block. */ +STATIC int +xrep_xattr_recover_leaf( + struct xrep_xattr *rx, + struct xfs_buf *bp) +{ + struct xfs_attr3_icleaf_hdr leafhdr; + struct xfs_scrub *sc = rx->sc; + struct xfs_mount *mp = sc->mp; + struct xfs_attr_leafblock *leaf; + struct xfs_attr_leaf_name_local *lentry; + struct xfs_attr_leaf_name_remote *rentry; + struct xfs_attr_leaf_entry *ent; + struct xfs_attr_leaf_entry *entries; + struct xchk_xattr_buf *ab = rx->sc->buf; + char *buf_end; + size_t off; + unsigned int nameidx; + unsigned int hdrsize; + int i; + int error = 0; + + bitmap_zero(ab->usedmap, mp->m_attr_geo->blksize); + + /* Check the leaf header */ + leaf = bp->b_addr; + xfs_attr3_leaf_hdr_from_disk(mp->m_attr_geo, &leafhdr, leaf); + hdrsize = xfs_attr3_leaf_hdr_size(leaf); + xchk_xattr_set_map(sc, ab->usedmap, 0, hdrsize); + entries = xfs_attr3_leaf_entryp(leaf); + + buf_end = (char *)bp->b_addr + mp->m_attr_geo->blksize; + for (i = 0, ent = entries; i < leafhdr.count; ent++, i++) { + if (xchk_should_terminate(sc, &error)) + return error; + + /* Skip key if it conflicts with something else? */ + off = (char *)ent - (char *)leaf; + if (!xchk_xattr_set_map(sc, ab->usedmap, off, + sizeof(xfs_attr_leaf_entry_t))) + continue; + + /* Check the name information. */ + nameidx = be16_to_cpu(ent->nameidx); + if (nameidx < leafhdr.firstused || + nameidx >= mp->m_attr_geo->blksize) + continue; + + if (ent->flags & XFS_ATTR_LOCAL) { + lentry = xfs_attr3_leaf_name_local(leaf, i); + error = xrep_xattr_salvage_local_attr(rx, ent, nameidx, + buf_end, lentry); + } else { + rentry = xfs_attr3_leaf_name_remote(leaf, i); + error = xrep_xattr_salvage_remote_attr(rx, ent, nameidx, + buf_end, rentry, i, bp); + } + if (error) + return error; + } + + return 0; +} + +/* Try to recover shortform attrs. */ +STATIC int +xrep_xattr_recover_sf( + struct xrep_xattr *rx) +{ + struct xfs_scrub *sc = rx->sc; + struct xchk_xattr_buf *ab = sc->buf; + struct xfs_attr_sf_hdr *hdr; + struct xfs_attr_sf_entry *sfe; + struct xfs_attr_sf_entry *next; + struct xfs_ifork *ifp; + unsigned char *end; + int i; + int error = 0; + + ifp = xfs_ifork_ptr(rx->sc->ip, XFS_ATTR_FORK); + hdr = ifp->if_data; + + bitmap_zero(ab->usedmap, ifp->if_bytes); + end = (unsigned char *)ifp->if_data + ifp->if_bytes; + xchk_xattr_set_map(sc, ab->usedmap, 0, sizeof(*hdr)); + + sfe = xfs_attr_sf_firstentry(hdr); + if ((unsigned char *)sfe > end) + return 0; + + for (i = 0; i < hdr->count; i++) { + if (xchk_should_terminate(sc, &error)) + return error; + + next = xfs_attr_sf_nextentry(sfe); + if ((unsigned char *)next > end) + break; + + if (xchk_xattr_set_map(sc, ab->usedmap, + (char *)sfe - (char *)hdr, + sizeof(struct xfs_attr_sf_entry))) { + /* + * No conflicts with the sf entry; let's save this + * attribute. + */ + error = xrep_xattr_salvage_sf_attr(rx, hdr, sfe); + if (error) + return error; + } + + sfe = next; + } + + return 0; +} + +/* + * Try to return a buffer of xattr data for a given physical extent. + * + * Because the buffer cache get function complains if it finds a buffer + * matching the block number but not matching the length, we must be careful to + * look for incore buffers (up to the maximum length of a remote value) that + * could be hiding anywhere in the physical range. If we find an incore + * buffer, we can pass that to the caller. Optionally, read a single block and + * pass that back. + * + * Note the subtlety that remote attr value blocks for which there is no incore + * buffer will be passed to the callback one block at a time. These buffers + * will not have any ops attached and must be staled to prevent aliasing with + * multiblock buffers once we drop the ILOCK. + */ +STATIC int +xrep_xattr_find_buf( + struct xfs_mount *mp, + xfs_fsblock_t fsbno, + xfs_extlen_t max_len, + bool can_read, + struct xfs_buf **bpp) +{ + struct xrep_bufscan scan = { + .daddr = XFS_FSB_TO_DADDR(mp, fsbno), + .max_sectors = xrep_bufscan_max_sectors(mp, max_len), + .daddr_step = XFS_FSB_TO_BB(mp, 1), + }; + struct xfs_buf *bp; + + while ((bp = xrep_bufscan_advance(mp, &scan)) != NULL) { + *bpp = bp; + return 0; + } + + if (!can_read) { + *bpp = NULL; + return 0; + } + + return xfs_buf_read(mp->m_ddev_targp, scan.daddr, XFS_FSB_TO_BB(mp, 1), + XBF_TRYLOCK, bpp, NULL); +} + +/* + * Deal with a buffer that we found during our walk of the attr fork. + * + * Attribute leaf and node blocks are simple -- they're a single block, so we + * can walk them one at a time and we never have to worry about discontiguous + * multiblock buffers like we do for directories. + * + * Unfortunately, remote attr blocks add a lot of complexity here. Each disk + * block is totally self contained, in the sense that the v5 header provides no + * indication that there could be more data in the next block. The incore + * buffers can span multiple blocks, though they never cross extent records. + * However, they don't necessarily start or end on an extent record boundary. + * Therefore, we need a special buffer find function to walk the buffer cache + * for us. + * + * The caller must hold the ILOCK on the file being repaired. We use + * XBF_TRYLOCK here to skip any locked buffer on the assumption that we don't + * own the block and don't want to hang the system on a potentially garbage + * buffer. + */ +STATIC int +xrep_xattr_recover_block( + struct xrep_xattr *rx, + xfs_dablk_t dabno, + xfs_fsblock_t fsbno, + xfs_extlen_t max_len, + xfs_extlen_t *actual_len) +{ + struct xfs_da_blkinfo *info; + struct xfs_buf *bp; + int error; + + error = xrep_xattr_find_buf(rx->sc->mp, fsbno, max_len, true, &bp); + if (error) + return error; + info = bp->b_addr; + *actual_len = XFS_BB_TO_FSB(rx->sc->mp, bp->b_length); + + trace_xrep_xattr_recover_leafblock(rx->sc->ip, dabno, + be16_to_cpu(info->magic)); + + /* + * If the buffer has the right magic number for an attr leaf block and + * passes a structure check (we don't care about checksums), salvage + * as much as we can from the block. */ + if (info->magic == cpu_to_be16(XFS_ATTR3_LEAF_MAGIC) && + xrep_buf_verify_struct(bp, &xfs_attr3_leaf_buf_ops) && + xfs_attr3_leaf_header_check(bp, rx->sc->ip->i_ino) == NULL) + error = xrep_xattr_recover_leaf(rx, bp); + + /* + * If the buffer didn't already have buffer ops set, it was read in by + * the _find_buf function and could very well be /part/ of a multiblock + * remote block. Mark it stale so that it doesn't hang around in + * memory to cause problems. + */ + if (bp->b_ops == NULL) + xfs_buf_stale(bp); + + xfs_buf_relse(bp); + return error; +} + +/* Insert one xattr key/value. */ +STATIC int +xrep_xattr_insert_rec( + struct xrep_xattr *rx, + const struct xrep_xattr_key *key) +{ + struct xfs_da_args args = { + .dp = rx->sc->tempip, + .attr_filter = key->flags, + .namelen = key->namelen, + .valuelen = key->valuelen, + .owner = rx->sc->ip->i_ino, + .geo = rx->sc->mp->m_attr_geo, + .whichfork = XFS_ATTR_FORK, + .op_flags = XFS_DA_OP_OKNOENT, + }; + struct xchk_xattr_buf *ab = rx->sc->buf; + int error; + + /* + * Grab pointers to the scrub buffer so that we can use them to insert + * attrs into the temp file. + */ + args.name = ab->name; + args.value = ab->value; + + /* + * The attribute name is stored near the end of the in-core buffer, + * though we reserve one more byte to ensure null termination. + */ + ab->name[XATTR_NAME_MAX] = 0; + + error = xfblob_load(rx->xattr_blobs, key->name_cookie, ab->name, + key->namelen); + if (error) + return error; + + error = xfblob_free(rx->xattr_blobs, key->name_cookie); + if (error) + return error; + + error = xfblob_load(rx->xattr_blobs, key->value_cookie, args.value, + key->valuelen); + if (error) + return error; + + error = xfblob_free(rx->xattr_blobs, key->value_cookie); + if (error) + return error; + + ab->name[key->namelen] = 0; + + if (key->flags & XFS_ATTR_PARENT) { + trace_xrep_xattr_insert_pptr(rx->sc->tempip, key->flags, + ab->name, key->namelen, ab->value, + key->valuelen); + args.op_flags |= XFS_DA_OP_LOGGED; + } else { + trace_xrep_xattr_insert_rec(rx->sc->tempip, key->flags, + ab->name, key->namelen, key->valuelen); + } + + /* + * xfs_attr_set creates and commits its own transaction. If the attr + * already exists, we'll just drop it during the rebuild. + */ + xfs_attr_sethash(&args); + error = xfs_attr_set(&args, XFS_ATTRUPDATE_CREATE, false); + if (error == -EEXIST) + error = 0; + + return error; +} + +/* + * Periodically flush salvaged attributes to the temporary file. This is done + * to reduce the memory requirements of the xattr rebuild because files can + * contain millions of attributes. + */ +STATIC int +xrep_xattr_flush_stashed( + struct xrep_xattr *rx) +{ + xfarray_idx_t array_cur; + int error; + + /* + * Entering this function, the scrub context has a reference to the + * inode being repaired, the temporary file, and a scrub transaction + * that we use during xattr salvaging to avoid livelocking if there + * are cycles in the xattr structures. We hold ILOCK_EXCL on both + * the inode being repaired, though it is not ijoined to the scrub + * transaction. + * + * To constrain kernel memory use, we occasionally flush salvaged + * xattrs from the xfarray and xfblob structures into the temporary + * file in preparation for exchanging the xattr structures at the end. + * Updating the temporary file requires a transaction, so we commit the + * scrub transaction and drop the two ILOCKs so that xfs_attr_set can + * allocate whatever transaction it wants. + * + * We still hold IOLOCK_EXCL on the inode being repaired, which + * prevents anyone from modifying the damaged xattr data while we + * repair it. + */ + error = xrep_trans_commit(rx->sc); + if (error) + return error; + xchk_iunlock(rx->sc, XFS_ILOCK_EXCL); + + /* + * Take the IOLOCK of the temporary file while we modify xattrs. This + * isn't strictly required because the temporary file is never revealed + * to userspace, but we follow the same locking rules. We still hold + * sc->ip's IOLOCK. + */ + error = xrep_tempfile_iolock_polled(rx->sc); + if (error) + return error; + + /* Add all the salvaged attrs to the temporary file. */ + foreach_xfarray_idx(rx->xattr_records, array_cur) { + struct xrep_xattr_key key; + + error = xfarray_load(rx->xattr_records, array_cur, &key); + if (error) + return error; + + error = xrep_xattr_insert_rec(rx, &key); + if (error) + return error; + } + + /* Empty out both arrays now that we've added the entries. */ + xfarray_truncate(rx->xattr_records); + xfblob_truncate(rx->xattr_blobs); + + xrep_tempfile_iounlock(rx->sc); + + /* Recreate the salvage transaction and relock the inode. */ + error = xchk_trans_alloc(rx->sc, 0); + if (error) + return error; + xchk_ilock(rx->sc, XFS_ILOCK_EXCL); + return 0; +} + +/* Decide if we've stashed too much xattr data in memory. */ +static inline bool +xrep_xattr_want_flush_stashed( + struct xrep_xattr *rx) +{ + unsigned long long bytes; + + if (!rx->can_flush) + return false; + + bytes = xfarray_bytes(rx->xattr_records) + + xfblob_bytes(rx->xattr_blobs); + return bytes > XREP_XATTR_MAX_STASH_BYTES; +} + +/* + * Did we observe rename changing parent pointer xattrs while we were flushing + * salvaged attrs? + */ +static inline bool +xrep_xattr_saw_pptr_conflict( + struct xrep_xattr *rx) +{ + bool ret; + + ASSERT(rx->can_flush); + + if (!xfs_has_parent(rx->sc->mp)) + return false; + + xfs_assert_ilocked(rx->sc->ip, XFS_ILOCK_EXCL); + + mutex_lock(&rx->lock); + ret = xfarray_bytes(rx->pptr_recs) > 0; + mutex_unlock(&rx->lock); + + return ret; +} + +/* + * Reset the entire repair state back to initial conditions, now that we've + * detected a parent pointer update to the attr structure while we were + * flushing salvaged attrs. See the locking notes in dir_repair.c for more + * information on why this is all necessary. + */ +STATIC int +xrep_xattr_full_reset( + struct xrep_xattr *rx) +{ + struct xfs_scrub *sc = rx->sc; + struct xfs_attr_sf_hdr *hdr; + struct xfs_ifork *ifp = &sc->tempip->i_af; + int error; + + trace_xrep_xattr_full_reset(sc->ip, sc->tempip); + + /* The temporary file's data fork had better not be in btree format. */ + if (sc->tempip->i_df.if_format == XFS_DINODE_FMT_BTREE) { + ASSERT(0); + return -EIO; + } + + /* + * We begin in transaction context with sc->ip ILOCKed but not joined + * to the transaction. To reset to the initial state, we must hold + * sc->ip's ILOCK to prevent rename from updating parent pointer + * information and the tempfile's ILOCK to clear its contents. + */ + xchk_iunlock(rx->sc, XFS_ILOCK_EXCL); + xrep_tempfile_ilock_both(sc); + xfs_trans_ijoin(sc->tp, sc->ip, 0); + xfs_trans_ijoin(sc->tp, sc->tempip, 0); + + /* + * Free all the blocks of the attr fork of the temp file, and reset + * it back to local format. + */ + if (xfs_ifork_has_extents(&sc->tempip->i_af)) { + error = xrep_reap_ifork(sc, sc->tempip, XFS_ATTR_FORK); + if (error) + return error; + + ASSERT(ifp->if_bytes == 0); + ifp->if_format = XFS_DINODE_FMT_LOCAL; + xfs_idata_realloc(sc->tempip, sizeof(*hdr), XFS_ATTR_FORK); + } + + /* Reinitialize the attr fork to an empty shortform structure. */ + hdr = ifp->if_data; + memset(hdr, 0, sizeof(*hdr)); + hdr->totsize = cpu_to_be16(sizeof(*hdr)); + xfs_trans_log_inode(sc->tp, sc->tempip, XFS_ILOG_CORE | XFS_ILOG_ADATA); + + /* + * Roll this transaction to commit our reset ondisk. The tempfile + * should no longer be joined to the transaction, so we drop its ILOCK. + * This should leave us in transaction context with sc->ip ILOCKed but + * not joined to the transaction. + */ + error = xrep_roll_trans(sc); + if (error) + return error; + xrep_tempfile_iunlock(sc); + + /* + * Erase any accumulated parent pointer updates now that we've erased + * the tempfile's attr fork. We're resetting the entire repair state + * back to where we were initially, except now we won't flush salvaged + * xattrs until the very end. + */ + mutex_lock(&rx->lock); + xfarray_truncate(rx->pptr_recs); + xfblob_truncate(rx->pptr_names); + mutex_unlock(&rx->lock); + + rx->can_flush = false; + rx->attrs_found = 0; + + ASSERT(xfarray_bytes(rx->xattr_records) == 0); + ASSERT(xfblob_bytes(rx->xattr_blobs) == 0); + return 0; +} + +/* Extract as many attribute keys and values as we can. */ +STATIC int +xrep_xattr_recover( + struct xrep_xattr *rx) +{ + struct xfs_bmbt_irec got; + struct xfs_scrub *sc = rx->sc; + struct xfs_da_geometry *geo = sc->mp->m_attr_geo; + xfs_fileoff_t offset; + xfs_extlen_t len; + xfs_dablk_t dabno; + int nmap; + int error; + +restart: + /* + * Iterate each xattr leaf block in the attr fork to scan them for any + * attributes that we might salvage. + */ + for (offset = 0; + offset < XFS_MAX_FILEOFF; + offset = got.br_startoff + got.br_blockcount) { + nmap = 1; + error = xfs_bmapi_read(sc->ip, offset, XFS_MAX_FILEOFF - offset, + &got, &nmap, XFS_BMAPI_ATTRFORK); + if (error) + return error; + if (nmap != 1) + return -EFSCORRUPTED; + if (!xfs_bmap_is_written_extent(&got)) + continue; + + for (dabno = round_up(got.br_startoff, geo->fsbcount); + dabno < got.br_startoff + got.br_blockcount; + dabno += len) { + xfs_fileoff_t curr_offset = dabno - got.br_startoff; + xfs_extlen_t maxlen; + + if (xchk_should_terminate(rx->sc, &error)) + return error; + + maxlen = min_t(xfs_filblks_t, INT_MAX, + got.br_blockcount - curr_offset); + error = xrep_xattr_recover_block(rx, dabno, + curr_offset + got.br_startblock, + maxlen, &len); + if (error) + return error; + + if (xrep_xattr_want_flush_stashed(rx)) { + error = xrep_xattr_flush_stashed(rx); + if (error) + return error; + + if (xrep_xattr_saw_pptr_conflict(rx)) { + error = xrep_xattr_full_reset(rx); + if (error) + return error; + + goto restart; + } + } + } + } + + return 0; +} + +/* + * Reset the extended attribute fork to a state where we can start re-adding + * the salvaged attributes. + */ +STATIC int +xrep_xattr_fork_remove( + struct xfs_scrub *sc, + struct xfs_inode *ip) +{ + struct xfs_attr_sf_hdr *hdr; + struct xfs_ifork *ifp = xfs_ifork_ptr(ip, XFS_ATTR_FORK); + + /* + * If the data fork is in btree format, we can't change di_forkoff + * because we could run afoul of the rule that the data fork isn't + * supposed to be in btree format if there's enough space in the fork + * that it could have used extents format. Instead, reinitialize the + * attr fork to have a shortform structure with zero attributes. + */ + if (ip->i_df.if_format == XFS_DINODE_FMT_BTREE) { + ifp->if_format = XFS_DINODE_FMT_LOCAL; + hdr = xfs_idata_realloc(ip, (int)sizeof(*hdr) - ifp->if_bytes, + XFS_ATTR_FORK); + hdr->count = 0; + hdr->totsize = cpu_to_be16(sizeof(*hdr)); + xfs_trans_log_inode(sc->tp, ip, + XFS_ILOG_CORE | XFS_ILOG_ADATA); + return 0; + } + + /* If we still have attr fork extents, something's wrong. */ + if (ifp->if_nextents != 0) { + struct xfs_iext_cursor icur; + struct xfs_bmbt_irec irec; + unsigned int i = 0; + + xfs_emerg(sc->mp, + "inode 0x%llx attr fork still has %llu attr extents, format %d?!", + ip->i_ino, ifp->if_nextents, ifp->if_format); + for_each_xfs_iext(ifp, &icur, &irec) { + xfs_err(sc->mp, + "[%u]: startoff %llu startblock %llu blockcount %llu state %u", + i++, irec.br_startoff, + irec.br_startblock, irec.br_blockcount, + irec.br_state); + } + ASSERT(0); + return -EFSCORRUPTED; + } + + xfs_attr_fork_remove(ip, sc->tp); + return 0; +} + +/* + * Free all the attribute fork blocks of the file being repaired and delete the + * fork. The caller must ILOCK the scrub file and join it to the transaction. + * This function returns with the inode joined to a clean transaction. + */ +int +xrep_xattr_reset_fork( + struct xfs_scrub *sc) +{ + int error; + + trace_xrep_xattr_reset_fork(sc->ip, sc->ip); + + /* Unmap all the attr blocks. */ + if (xfs_ifork_has_extents(&sc->ip->i_af)) { + error = xrep_reap_ifork(sc, sc->ip, XFS_ATTR_FORK); + if (error) + return error; + } + + error = xrep_xattr_fork_remove(sc, sc->ip); + if (error) + return error; + + return xfs_trans_roll_inode(&sc->tp, sc->ip); +} + +/* + * Free all the attribute fork blocks of the temporary file and delete the attr + * fork. The caller must ILOCK the tempfile and join it to the transaction. + * This function returns with the inode joined to a clean scrub transaction. + */ +int +xrep_xattr_reset_tempfile_fork( + struct xfs_scrub *sc) +{ + int error; + + trace_xrep_xattr_reset_fork(sc->ip, sc->tempip); + + /* + * Wipe out the attr fork of the temp file so that regular inode + * inactivation won't trip over the corrupt attr fork. + */ + if (xfs_ifork_has_extents(&sc->tempip->i_af)) { + error = xrep_reap_ifork(sc, sc->tempip, XFS_ATTR_FORK); + if (error) + return error; + } + + return xrep_xattr_fork_remove(sc, sc->tempip); +} + +/* + * Find all the extended attributes for this inode by scraping them out of the + * attribute key blocks by hand, and flushing them into the temp file. + * When we're done, free the staging memory before exchanging the xattr + * structures to reduce memory usage. + */ +STATIC int +xrep_xattr_salvage_attributes( + struct xrep_xattr *rx) +{ + struct xfs_inode *ip = rx->sc->ip; + int error; + + /* Short format xattrs are easy! */ + if (rx->sc->ip->i_af.if_format == XFS_DINODE_FMT_LOCAL) { + error = xrep_xattr_recover_sf(rx); + if (error) + return error; + + return xrep_xattr_flush_stashed(rx); + } + + /* + * For non-inline xattr structures, the salvage function scans the + * buffer cache looking for potential attr leaf blocks. The scan + * requires the ability to lock any buffer found and runs independently + * of any transaction <-> buffer item <-> buffer linkage. Therefore, + * roll the transaction to ensure there are no buffers joined. We hold + * the ILOCK independently of the transaction. + */ + error = xfs_trans_roll(&rx->sc->tp); + if (error) + return error; + + error = xfs_iread_extents(rx->sc->tp, ip, XFS_ATTR_FORK); + if (error) + return error; + + error = xrep_xattr_recover(rx); + if (error) + return error; + + return xrep_xattr_flush_stashed(rx); +} + +/* + * Add this stashed incore parent pointer to the temporary file. The caller + * must hold the tempdir's IOLOCK, must not hold any ILOCKs, and must not be in + * transaction context. + */ +STATIC int +xrep_xattr_replay_pptr_update( + struct xrep_xattr *rx, + const struct xfs_name *xname, + struct xrep_xattr_pptr *pptr) +{ + struct xfs_scrub *sc = rx->sc; + int error; + + switch (pptr->action) { + case XREP_XATTR_PPTR_ADD: + /* Create parent pointer. */ + trace_xrep_xattr_replay_parentadd(sc->tempip, xname, + &pptr->pptr_rec); + + error = xfs_parent_set(sc->tempip, sc->ip->i_ino, xname, + &pptr->pptr_rec, &rx->pptr_args); + ASSERT(error != -EEXIST); + return error; + case XREP_XATTR_PPTR_REMOVE: + /* Remove parent pointer. */ + trace_xrep_xattr_replay_parentremove(sc->tempip, xname, + &pptr->pptr_rec); + + error = xfs_parent_unset(sc->tempip, sc->ip->i_ino, xname, + &pptr->pptr_rec, &rx->pptr_args); + ASSERT(error != -ENOATTR); + return error; + } + + ASSERT(0); + return -EIO; +} + +/* + * Flush stashed parent pointer updates that have been recorded by the scanner. + * This is done to reduce the memory requirements of the xattr rebuild, since + * files can have a lot of hardlinks and the fs can be busy. + * + * Caller must not hold transactions or ILOCKs. Caller must hold the tempfile + * IOLOCK. + */ +STATIC int +xrep_xattr_replay_pptr_updates( + struct xrep_xattr *rx) +{ + xfarray_idx_t array_cur; + int error; + + mutex_lock(&rx->lock); + foreach_xfarray_idx(rx->pptr_recs, array_cur) { + struct xrep_xattr_pptr pptr; + + error = xfarray_load(rx->pptr_recs, array_cur, &pptr); + if (error) + goto out_unlock; + + error = xfblob_loadname(rx->pptr_names, pptr.name_cookie, + &rx->xname, pptr.namelen); + if (error) + goto out_unlock; + mutex_unlock(&rx->lock); + + error = xrep_xattr_replay_pptr_update(rx, &rx->xname, &pptr); + if (error) + return error; + + mutex_lock(&rx->lock); + } + + /* Empty out both arrays now that we've added the entries. */ + xfarray_truncate(rx->pptr_recs); + xfblob_truncate(rx->pptr_names); + mutex_unlock(&rx->lock); + return 0; +out_unlock: + mutex_unlock(&rx->lock); + return error; +} + +/* + * Remember that we want to create a parent pointer in the tempfile. These + * stashed actions will be replayed later. + */ +STATIC int +xrep_xattr_stash_parentadd( + struct xrep_xattr *rx, + const struct xfs_name *name, + const struct xfs_inode *dp) +{ + struct xrep_xattr_pptr pptr = { + .action = XREP_XATTR_PPTR_ADD, + .namelen = name->len, + }; + int error; + + trace_xrep_xattr_stash_parentadd(rx->sc->tempip, dp, name); + + xfs_inode_to_parent_rec(&pptr.pptr_rec, dp); + error = xfblob_storename(rx->pptr_names, &pptr.name_cookie, name); + if (error) + return error; + + return xfarray_append(rx->pptr_recs, &pptr); +} + +/* + * Remember that we want to remove a parent pointer from the tempfile. These + * stashed actions will be replayed later. + */ +STATIC int +xrep_xattr_stash_parentremove( + struct xrep_xattr *rx, + const struct xfs_name *name, + const struct xfs_inode *dp) +{ + struct xrep_xattr_pptr pptr = { + .action = XREP_XATTR_PPTR_REMOVE, + .namelen = name->len, + }; + int error; + + trace_xrep_xattr_stash_parentremove(rx->sc->tempip, dp, name); + + xfs_inode_to_parent_rec(&pptr.pptr_rec, dp); + error = xfblob_storename(rx->pptr_names, &pptr.name_cookie, name); + if (error) + return error; + + return xfarray_append(rx->pptr_recs, &pptr); +} + +/* + * Capture dirent updates being made by other threads. We will have to replay + * the parent pointer updates before exchanging attr forks. + */ +STATIC int +xrep_xattr_live_dirent_update( + struct notifier_block *nb, + unsigned long action, + void *data) +{ + struct xfs_dir_update_params *p = data; + struct xrep_xattr *rx; + struct xfs_scrub *sc; + int error; + + rx = container_of(nb, struct xrep_xattr, dhook.dirent_hook.nb); + sc = rx->sc; + + /* + * This thread updated a dirent that points to the file that we're + * repairing, so stash the update for replay against the temporary + * file. + */ + if (p->ip->i_ino != sc->ip->i_ino) + return NOTIFY_DONE; + + mutex_lock(&rx->lock); + if (p->delta > 0) + error = xrep_xattr_stash_parentadd(rx, p->name, p->dp); + else + error = xrep_xattr_stash_parentremove(rx, p->name, p->dp); + if (error) + rx->live_update_aborted = true; + mutex_unlock(&rx->lock); + return NOTIFY_DONE; +} + +/* + * Prepare both inodes' attribute forks for an exchange. Promote the tempfile + * from short format to leaf format, and if the file being repaired has a short + * format attr fork, turn it into an empty extent list. + */ +STATIC int +xrep_xattr_swap_prep( + struct xfs_scrub *sc, + bool temp_local, + bool ip_local) +{ + int error; + + /* + * If the tempfile's attributes are in shortform format, convert that + * to a single leaf extent so that we can use the atomic mapping + * exchange. + */ + if (temp_local) { + struct xfs_da_args args = { + .dp = sc->tempip, + .geo = sc->mp->m_attr_geo, + .whichfork = XFS_ATTR_FORK, + .trans = sc->tp, + .total = 1, + .owner = sc->ip->i_ino, + }; + + error = xfs_attr_shortform_to_leaf(&args); + if (error) + return error; + + /* + * Roll the deferred log items to get us back to a clean + * transaction. + */ + error = xfs_defer_finish(&sc->tp); + if (error) + return error; + } + + /* + * If the file being repaired had a shortform attribute fork, convert + * that to an empty extent list in preparation for the atomic mapping + * exchange. + */ + if (ip_local) { + struct xfs_ifork *ifp; + + ifp = xfs_ifork_ptr(sc->ip, XFS_ATTR_FORK); + + xfs_idestroy_fork(ifp); + ifp->if_format = XFS_DINODE_FMT_EXTENTS; + ifp->if_nextents = 0; + ifp->if_bytes = 0; + ifp->if_data = NULL; + ifp->if_height = 0; + + xfs_trans_log_inode(sc->tp, sc->ip, + XFS_ILOG_CORE | XFS_ILOG_ADATA); + } + + return 0; +} + +/* Exchange the temporary file's attribute fork with the one being repaired. */ +int +xrep_xattr_swap( + struct xfs_scrub *sc, + struct xrep_tempexch *tx) +{ + bool ip_local, temp_local; + int error = 0; + + ip_local = sc->ip->i_af.if_format == XFS_DINODE_FMT_LOCAL; + temp_local = sc->tempip->i_af.if_format == XFS_DINODE_FMT_LOCAL; + + /* + * If the both files have a local format attr fork and the rebuilt + * xattr data would fit in the repaired file's attr fork, just copy + * the contents from the tempfile and declare ourselves done. + */ + if (ip_local && temp_local) { + int forkoff; + int newsize; + + newsize = xfs_attr_sf_totsize(sc->tempip); + forkoff = xfs_attr_shortform_bytesfit(sc->ip, newsize); + if (forkoff > 0) { + sc->ip->i_forkoff = forkoff; + xrep_tempfile_copyout_local(sc, XFS_ATTR_FORK); + return 0; + } + } + + /* Otherwise, make sure both attr forks are in block-mapping mode. */ + error = xrep_xattr_swap_prep(sc, temp_local, ip_local); + if (error) + return error; + + return xrep_tempexch_contents(sc, tx); +} + +/* + * Finish replaying stashed parent pointer updates, allocate a transaction for + * exchanging extent mappings, and take the ILOCKs of both files before we + * commit the new extended attribute structure. + */ +STATIC int +xrep_xattr_finalize_tempfile( + struct xrep_xattr *rx) +{ + struct xfs_scrub *sc = rx->sc; + int error; + + if (!xfs_has_parent(sc->mp)) + return xrep_tempexch_trans_alloc(sc, XFS_ATTR_FORK, &rx->tx); + + /* + * Repair relies on the ILOCK to quiesce all possible xattr updates. + * Replay all queued parent pointer updates into the tempfile before + * exchanging the contents, even if that means dropping the ILOCKs and + * the transaction. + */ + do { + error = xrep_xattr_replay_pptr_updates(rx); + if (error) + return error; + + error = xrep_tempexch_trans_alloc(sc, XFS_ATTR_FORK, &rx->tx); + if (error) + return error; + + if (xfarray_length(rx->pptr_recs) == 0) + break; + + xchk_trans_cancel(sc); + xrep_tempfile_iunlock_both(sc); + } while (!xchk_should_terminate(sc, &error)); + return error; +} + +/* + * Exchange the new extended attribute data (which we created in the tempfile) + * with the file being repaired. + */ +STATIC int +xrep_xattr_rebuild_tree( + struct xrep_xattr *rx) +{ + struct xfs_scrub *sc = rx->sc; + int error; + + /* + * If we didn't find any attributes to salvage, repair the file by + * zapping its attr fork. + */ + if (rx->attrs_found == 0) { + xfs_trans_ijoin(sc->tp, sc->ip, 0); + error = xrep_xattr_reset_fork(sc); + if (error) + return error; + + goto forget_acls; + } + + trace_xrep_xattr_rebuild_tree(sc->ip, sc->tempip); + + /* + * Commit the repair transaction and drop the ILOCKs so that we can use + * the atomic file content exchange helper functions to compute the + * correct resource reservations. + * + * We still hold IOLOCK_EXCL (aka i_rwsem) which will prevent xattr + * modifications, but there's nothing to prevent userspace from reading + * the attributes until we're ready for the exchange operation. Reads + * will return -EIO without shutting down the fs, so we're ok with + * that. + */ + error = xrep_trans_commit(sc); + if (error) + return error; + + xchk_iunlock(sc, XFS_ILOCK_EXCL); + + /* + * Take the IOLOCK on the temporary file so that we can run xattr + * operations with the same locks held as we would for a normal file. + * We still hold sc->ip's IOLOCK. + */ + error = xrep_tempfile_iolock_polled(rx->sc); + if (error) + return error; + + /* + * Allocate transaction, lock inodes, and make sure that we've replayed + * all the stashed parent pointer updates to the temp file. After this + * point, we're ready to exchange attr fork mappings. + */ + error = xrep_xattr_finalize_tempfile(rx); + if (error) + return error; + + /* + * Exchange the blocks mapped by the tempfile's attr fork with the file + * being repaired. The old attr blocks will then be attached to the + * tempfile, so reap its attr fork. + */ + error = xrep_xattr_swap(sc, &rx->tx); + if (error) + return error; + + error = xrep_xattr_reset_tempfile_fork(sc); + if (error) + return error; + + /* + * Roll to get a transaction without any inodes joined to it. Then we + * can drop the tempfile's ILOCK and IOLOCK before doing more work on + * the scrub target file. + */ + error = xfs_trans_roll(&sc->tp); + if (error) + return error; + + xrep_tempfile_iunlock(sc); + xrep_tempfile_iounlock(sc); + +forget_acls: + /* Invalidate cached ACLs now that we've reloaded all the xattrs. */ + xfs_forget_acl(VFS_I(sc->ip), SGI_ACL_FILE); + xfs_forget_acl(VFS_I(sc->ip), SGI_ACL_DEFAULT); + return 0; +} + +/* Tear down all the incore scan stuff we created. */ +STATIC void +xrep_xattr_teardown( + struct xrep_xattr *rx) +{ + if (xfs_has_parent(rx->sc->mp)) + xfs_dir_hook_del(rx->sc->mp, &rx->dhook); + if (rx->pptr_names) + xfblob_destroy(rx->pptr_names); + if (rx->pptr_recs) + xfarray_destroy(rx->pptr_recs); + xfblob_destroy(rx->xattr_blobs); + xfarray_destroy(rx->xattr_records); + mutex_destroy(&rx->lock); + kfree(rx); +} + +/* Set up the filesystem scan so we can regenerate extended attributes. */ +STATIC int +xrep_xattr_setup_scan( + struct xfs_scrub *sc, + struct xrep_xattr **rxp) +{ + struct xrep_xattr *rx; + char *descr; + int max_len; + int error; + + rx = kzalloc(sizeof(struct xrep_xattr), XCHK_GFP_FLAGS); + if (!rx) + return -ENOMEM; + rx->sc = sc; + rx->can_flush = true; + rx->xname.name = rx->namebuf; + + mutex_init(&rx->lock); + + /* + * Allocate enough memory to handle loading local attr values from the + * xfblob data while flushing stashed attrs to the temporary file. + * We only realloc the buffer when salvaging remote attr values. + */ + max_len = xfs_attr_leaf_entsize_local_max(sc->mp->m_attr_geo->blksize); + error = xchk_setup_xattr_buf(rx->sc, max_len); + if (error == -ENOMEM) + error = -EDEADLOCK; + if (error) + goto out_rx; + + /* Set up some staging for salvaged attribute keys and values */ + descr = xchk_xfile_ino_descr(sc, "xattr keys"); + error = xfarray_create(descr, 0, sizeof(struct xrep_xattr_key), + &rx->xattr_records); + kfree(descr); + if (error) + goto out_rx; + + descr = xchk_xfile_ino_descr(sc, "xattr names"); + error = xfblob_create(descr, &rx->xattr_blobs); + kfree(descr); + if (error) + goto out_keys; + + if (xfs_has_parent(sc->mp)) { + ASSERT(sc->flags & XCHK_FSGATES_DIRENTS); + + descr = xchk_xfile_ino_descr(sc, + "xattr retained parent pointer entries"); + error = xfarray_create(descr, 0, + sizeof(struct xrep_xattr_pptr), + &rx->pptr_recs); + kfree(descr); + if (error) + goto out_values; + + descr = xchk_xfile_ino_descr(sc, + "xattr retained parent pointer names"); + error = xfblob_create(descr, &rx->pptr_names); + kfree(descr); + if (error) + goto out_pprecs; + + xfs_dir_hook_setup(&rx->dhook, xrep_xattr_live_dirent_update); + error = xfs_dir_hook_add(sc->mp, &rx->dhook); + if (error) + goto out_ppnames; + } + + *rxp = rx; + return 0; +out_ppnames: + xfblob_destroy(rx->pptr_names); +out_pprecs: + xfarray_destroy(rx->pptr_recs); +out_values: + xfblob_destroy(rx->xattr_blobs); +out_keys: + xfarray_destroy(rx->xattr_records); +out_rx: + mutex_destroy(&rx->lock); + kfree(rx); + return error; +} + +/* + * Repair the extended attribute metadata. + * + * XXX: Remote attribute value buffers encompass the entire (up to 64k) buffer. + * The buffer cache in XFS can't handle aliased multiblock buffers, so this + * might misbehave if the attr fork is crosslinked with other filesystem + * metadata. + */ +int +xrep_xattr( + struct xfs_scrub *sc) +{ + struct xrep_xattr *rx = NULL; + int error; + + if (!xfs_inode_hasattr(sc->ip)) + return -ENOENT; + + /* The rmapbt is required to reap the old attr fork. */ + if (!xfs_has_rmapbt(sc->mp)) + return -EOPNOTSUPP; + /* We require atomic file exchange range to rebuild anything. */ + if (!xfs_has_exchange_range(sc->mp)) + return -EOPNOTSUPP; + + error = xrep_xattr_setup_scan(sc, &rx); + if (error) + return error; + + ASSERT(sc->ilock_flags & XFS_ILOCK_EXCL); + + error = xrep_xattr_salvage_attributes(rx); + if (error) + goto out_scan; + + if (rx->live_update_aborted) { + error = -EIO; + goto out_scan; + } + + /* Last chance to abort before we start committing fixes. */ + if (xchk_should_terminate(sc, &error)) + goto out_scan; + + error = xrep_xattr_rebuild_tree(rx); + if (error) + goto out_scan; + +out_scan: + xrep_xattr_teardown(rx); + return error; +} |