From: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
Use the reverse-mapping btree information to rebuild an inode fork.
Signed-off-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
---
fs/xfs/Makefile | 1
fs/xfs/scrub/bmap.c | 8 +
fs/xfs/scrub/bmap_repair.c | 398 ++++++++++++++++++++++++++++++++++++++++++++
fs/xfs/scrub/repair.h | 4
fs/xfs/scrub/scrub.c | 2
fs/xfs/xfs_trans.c | 54 ++++++
fs/xfs/xfs_trans.h | 2
7 files changed, 469 insertions(+)
create mode 100644 fs/xfs/scrub/bmap_repair.c
diff --git a/fs/xfs/Makefile b/fs/xfs/Makefile
index b413fb7..7a44ddbac 100644
--- a/fs/xfs/Makefile
+++ b/fs/xfs/Makefile
@@ -176,6 +176,7 @@ ifeq ($(CONFIG_XFS_ONLINE_REPAIR),y)
xfs-y += $(addprefix scrub/, \
agheader_repair.o \
alloc_repair.o \
+ bmap_repair.o \
ialloc_repair.o \
inode_repair.o \
refcount_repair.o \
diff --git a/fs/xfs/scrub/bmap.c b/fs/xfs/scrub/bmap.c
index 4805d7f..0d881e1 100644
--- a/fs/xfs/scrub/bmap.c
+++ b/fs/xfs/scrub/bmap.c
@@ -72,6 +72,14 @@ xfs_scrub_setup_inode_bmap(
error = filemap_write_and_wait(VFS_I(sc->ip)->i_mapping);
if (error)
goto out;
+
+ /* Drop the page cache if we're repairing block mappings. */
+ if (sc->sm->sm_flags & XFS_SCRUB_IFLAG_REPAIR) {
+ error = invalidate_inode_pages2(
+ VFS_I(sc->ip)->i_mapping);
+ if (error)
+ goto out;
+ }
}
error = xfs_scrub_trans_alloc(sc->sm, mp, 0, &sc->tp);
diff --git a/fs/xfs/scrub/bmap_repair.c b/fs/xfs/scrub/bmap_repair.c
new file mode 100644
index 0000000..9e04366
--- /dev/null
+++ b/fs/xfs/scrub/bmap_repair.c
@@ -0,0 +1,398 @@
+/*
+ * Copyright (C) 2018 Oracle. All Rights Reserved.
+ *
+ * Author: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it would be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+#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_inode_fork.h"
+#include "xfs_alloc.h"
+#include "xfs_rtalloc.h"
+#include "xfs_bmap.h"
+#include "xfs_bmap_util.h"
+#include "xfs_bmap_btree.h"
+#include "xfs_rmap.h"
+#include "xfs_rmap_btree.h"
+#include "xfs_refcount.h"
+#include "xfs_quota.h"
+#include "scrub/xfs_scrub.h"
+#include "scrub/scrub.h"
+#include "scrub/common.h"
+#include "scrub/btree.h"
+#include "scrub/trace.h"
+#include "scrub/repair.h"
+
+/* Inode fork block mapping (BMBT) repair. */
+
+struct xfs_repair_bmap_extent {
+ struct list_head list;
+ struct xfs_rmap_irec rmap;
+ xfs_agnumber_t agno;
+};
+
+struct xfs_repair_bmap {
+ struct list_head extlist;
+ struct xfs_repair_extent_list btlist;
+ struct xfs_repair_bmap_extent ext; /* most files have 1 extent */
+ struct xfs_scrub_context *sc;
+ xfs_ino_t ino;
+ xfs_rfsblock_t otherfork_blocks;
+ xfs_rfsblock_t bmbt_blocks;
+ xfs_extnum_t extents;
+ int whichfork;
+};
+
+/* Record extents that belong to this inode's fork. */
+STATIC int
+xfs_repair_bmap_extent_fn(
+ struct xfs_btree_cur *cur,
+ struct xfs_rmap_irec *rec,
+ void *priv)
+{
+ struct xfs_repair_bmap *rb = priv;
+ struct xfs_repair_bmap_extent *rbe;
+ struct xfs_mount *mp = cur->bc_mp;
+ xfs_fsblock_t fsbno;
+ int error = 0;
+
+ if (xfs_scrub_should_terminate(rb->sc, &error))
+ return error;
+
+ /* Skip extents which are not owned by this inode and fork. */
+ if (rec->rm_owner != rb->ino) {
+ return 0;
+ } else if (rb->whichfork == XFS_DATA_FORK &&
+ (rec->rm_flags & XFS_RMAP_ATTR_FORK)) {
+ rb->otherfork_blocks += rec->rm_blockcount;
+ return 0;
+ } else if (rb->whichfork == XFS_ATTR_FORK &&
+ !(rec->rm_flags & XFS_RMAP_ATTR_FORK)) {
+ rb->otherfork_blocks += rec->rm_blockcount;
+ return 0;
+ }
+
+ rb->extents++;
+
+ /* Delete the old bmbt blocks later. */
+ if (rec->rm_flags & XFS_RMAP_BMBT_BLOCK) {
+ fsbno = XFS_AGB_TO_FSB(mp, cur->bc_private.a.agno,
+ rec->rm_startblock);
+ rb->bmbt_blocks += rec->rm_blockcount;
+ return xfs_repair_collect_btree_extent(rb->sc, &rb->btlist,
+ fsbno, rec->rm_blockcount);
+ }
+
+ /* Remember this rmap. */
+ trace_xfs_repair_bmap_extent_fn(mp, cur->bc_private.a.agno,
+ rec->rm_startblock, rec->rm_blockcount, rec->rm_owner,
+ rec->rm_offset, rec->rm_flags);
+
+ if (list_empty(&rb->extlist)) {
+ rbe = &rb->ext;
+ } else {
+ rbe = kmem_alloc(sizeof(struct xfs_repair_bmap_extent),
+ KM_MAYFAIL | KM_NOFS);
+ if (!rbe)
+ return -ENOMEM;
+ }
+
+ INIT_LIST_HEAD(&rbe->list);
+ rbe->rmap = *rec;
+ rbe->agno = cur->bc_private.a.agno;
+ list_add_tail(&rbe->list, &rb->extlist);
+
+ return 0;
+}
+
+/* Compare two bmap extents. */
+static int
+xfs_repair_bmap_extent_cmp(
+ void *priv,
+ struct list_head *a,
+ struct list_head *b)
+{
+ struct xfs_repair_bmap_extent *ap;
+ struct xfs_repair_bmap_extent *bp;
+
+ ap = container_of(a, struct xfs_repair_bmap_extent, list);
+ bp = container_of(b, struct xfs_repair_bmap_extent, list);
+
+ if (ap->rmap.rm_offset > bp->rmap.rm_offset)
+ return 1;
+ else if (ap->rmap.rm_offset < bp->rmap.rm_offset)
+ return -1;
+ return 0;
+}
+
+/* Scan one AG for reverse mappings that we can turn into extent maps. */
+STATIC int
+xfs_repair_bmap_scan_ag(
+ struct xfs_repair_bmap *rb,
+ xfs_agnumber_t agno)
+{
+ struct xfs_scrub_context *sc = rb->sc;
+ struct xfs_mount *mp = sc->mp;
+ struct xfs_buf *agf_bp = NULL;
+ struct xfs_btree_cur *cur;
+ int error;
+
+ error = xfs_alloc_read_agf(mp, sc->tp, agno, 0, &agf_bp);
+ if (error)
+ return error;
+ if (!agf_bp)
+ return -ENOMEM;
+ cur = xfs_rmapbt_init_cursor(mp, sc->tp, agf_bp, agno);
+ error = xfs_rmap_query_all(cur, xfs_repair_bmap_extent_fn, rb);
+ if (error == XFS_BTREE_QUERY_RANGE_ABORT)
+ error = 0;
+ xfs_btree_del_cursor(cur, error ? XFS_BTREE_ERROR :
+ XFS_BTREE_NOERROR);
+ xfs_trans_brelse(sc->tp, agf_bp);
+ return error;
+}
+
+/* Insert bmap records into an inode fork, given an rmap. */
+STATIC int
+xfs_repair_bmap_insert_rec(
+ struct xfs_scrub_context *sc,
+ struct xfs_repair_bmap_extent *rbe,
+ int baseflags)
+{
+ struct xfs_bmbt_irec bmap;
+ struct xfs_defer_ops dfops;
+ xfs_fsblock_t firstfsb;
+ xfs_extlen_t extlen;
+ int flags;
+ int error = 0;
+
+ /* Form the "new" mapping... */
+ bmap.br_startblock = XFS_AGB_TO_FSB(sc->mp, rbe->agno,
+ rbe->rmap.rm_startblock);
+ bmap.br_startoff = rbe->rmap.rm_offset;
+
+ flags = 0;
+ if (rbe->rmap.rm_flags & XFS_RMAP_UNWRITTEN)
+ flags = XFS_BMAPI_PREALLOC;
+ while (rbe->rmap.rm_blockcount > 0) {
+ xfs_defer_init(&dfops, &firstfsb);
+ extlen = min_t(xfs_extlen_t, rbe->rmap.rm_blockcount,
+ MAXEXTLEN);
+ bmap.br_blockcount = extlen;
+
+ /* Re-add the extent to the fork. */
+ error = xfs_bmapi_remap(sc->tp, sc->ip,
+ bmap.br_startoff, extlen,
+ bmap.br_startblock, &dfops,
+ baseflags | flags);
+ if (error)
+ goto out_cancel;
+
+ bmap.br_startblock += extlen;
+ bmap.br_startoff += extlen;
+ rbe->rmap.rm_blockcount -= extlen;
+ error = xfs_defer_ijoin(&dfops, sc->ip);
+ if (error)
+ goto out_cancel;
+ error = xfs_defer_finish(&sc->tp, &dfops);
+ if (error)
+ goto out;
+ /* Make sure we roll the transaction. */
+ error = xfs_trans_roll_inode(&sc->tp, sc->ip);
+ if (error)
+ goto out;
+ }
+
+ return 0;
+out_cancel:
+ xfs_defer_cancel(&dfops);
+out:
+ return error;
+}
+
+/* Repair an inode fork. */
+STATIC int
+xfs_repair_bmap(
+ struct xfs_scrub_context *sc,
+ int whichfork)
+{
+ struct xfs_repair_bmap rb;
+ struct xfs_owner_info oinfo;
+ struct xfs_inode *ip = sc->ip;
+ struct xfs_mount *mp = ip->i_mount;
+ struct xfs_repair_bmap_extent *rbe;
+ struct xfs_repair_bmap_extent *n;
+ xfs_agnumber_t agno;
+ unsigned int resblks;
+ int baseflags;
+ int error = 0;
+
+ ASSERT(whichfork == XFS_DATA_FORK || whichfork == XFS_ATTR_FORK);
+
+ /* Don't know how to repair the other fork formats. */
+ if (XFS_IFORK_FORMAT(sc->ip, whichfork) != XFS_DINODE_FMT_EXTENTS &&
+ XFS_IFORK_FORMAT(sc->ip, whichfork) != XFS_DINODE_FMT_BTREE)
+ return -EOPNOTSUPP;
+
+ /* Only files, symlinks, and directories get to have data forks. */
+ if (whichfork == XFS_DATA_FORK && !S_ISREG(VFS_I(ip)->i_mode) &&
+ !S_ISDIR(VFS_I(ip)->i_mode) && !S_ISLNK(VFS_I(ip)->i_mode))
+ return -EINVAL;
+
+ /* If we somehow have delalloc extents, forget it. */
+ if (whichfork == XFS_DATA_FORK && ip->i_delayed_blks)
+ return -EBUSY;
+
+ /*
+ * If there's no attr fork area in the inode, there's
+ * no attr fork to rebuild.
+ */
+ if (whichfork == XFS_ATTR_FORK && !XFS_IFORK_Q(ip))
+ return -ENOENT;
+
+ /* We require the rmapbt to rebuild anything. */
+ if (!xfs_sb_version_hasrmapbt(&mp->m_sb))
+ return -EOPNOTSUPP;
+
+ /* Don't know how to rebuild realtime data forks. */
+ if (XFS_IS_REALTIME_INODE(ip) && whichfork == XFS_DATA_FORK)
+ return -EOPNOTSUPP;
+
+ /*
+ * If this is a file data fork, wait for all pending directio to
+ * complete, then tear everything out of the page cache.
+ */
+ if (S_ISREG(VFS_I(ip)->i_mode) && whichfork == XFS_DATA_FORK) {
+ inode_dio_wait(VFS_I(ip));
+ truncate_inode_pages(VFS_I(ip)->i_mapping, 0);
+ }
+
+ /* Collect all reverse mappings for this fork's extents. */
+ memset(&rb, 0, sizeof(rb));
+ INIT_LIST_HEAD(&rb.extlist);
+ xfs_repair_init_extent_list(&rb.btlist);
+ rb.ino = ip->i_ino;
+ rb.whichfork = whichfork;
+ rb.sc = sc;
+
+ /* Iterate the rmaps for extents. */
+ for (agno = 0; agno < mp->m_sb.sb_agcount; agno++) {
+ error = xfs_repair_bmap_scan_ag(&rb, agno);
+ if (error)
+ goto out;
+ }
+
+ /*
+ * Guess how many blocks we're going to need to rebuild an entire bmap
+ * from the number of extents we found, and get ourselves a new
+ * transaction with proper block reservations.
+ */
+ resblks = xfs_bmbt_calc_size(mp, rb.extents);
+ error = xfs_trans_reserve_more(sc->tp, resblks, 0);
+ if (error)
+ goto out;
+
+ /* Blow out the in-core fork and zero the on-disk fork. */
+ sc->ip->i_d.di_nblocks = rb.otherfork_blocks;
+ xfs_trans_ijoin(sc->tp, sc->ip, 0);
+ if (XFS_IFORK_PTR(ip, whichfork) != NULL)
+ xfs_idestroy_fork(sc->ip, whichfork);
+ XFS_IFORK_FMT_SET(sc->ip, whichfork, XFS_DINODE_FMT_EXTENTS);
+ XFS_IFORK_NEXT_SET(sc->ip, whichfork, 0);
+
+ /* Reinitialize the on-disk fork. */
+ if (whichfork == XFS_DATA_FORK) {
+ memset(&ip->i_df, 0, sizeof(struct xfs_ifork));
+ ip->i_df.if_flags |= XFS_IFEXTENTS;
+ } else if (whichfork == XFS_ATTR_FORK) {
+ if (list_empty(&rb.extlist))
+ ip->i_afp = NULL;
+ else {
+ ip->i_afp = kmem_zone_zalloc(xfs_ifork_zone, KM_NOFS);
+ ip->i_afp->if_flags |= XFS_IFEXTENTS;
+ }
+ }
+ xfs_trans_log_inode(sc->tp, sc->ip, XFS_ILOG_CORE);
+ error = xfs_trans_roll_inode(&sc->tp, sc->ip);
+ if (error)
+ goto out;
+
+ baseflags = XFS_BMAPI_NORMAP;
+ if (whichfork == XFS_ATTR_FORK)
+ baseflags |= XFS_BMAPI_ATTRFORK;
+
+ /* Release quota counts for the old bmbt blocks. */
+ if (rb.bmbt_blocks) {
+ xfs_trans_mod_dquot_byino(sc->tp, sc->ip, XFS_TRANS_DQ_BCOUNT,
+ -rb.bmbt_blocks);
+ error = xfs_trans_roll_inode(&sc->tp, sc->ip);
+ if (error)
+ goto out;
+ }
+
+ /* "Remap" the extents into the fork. */
+ list_sort(NULL, &rb.extlist, xfs_repair_bmap_extent_cmp);
+ list_for_each_entry_safe(rbe, n, &rb.extlist, list) {
+ error = xfs_repair_bmap_insert_rec(sc, rbe, baseflags);
+ if (error)
+ goto out;
+ list_del(&rbe->list);
+ if (rbe != &rb.ext)
+ kmem_free(rbe);
+ }
+
+ /* Dispose of all the old bmbt blocks. */
+ xfs_rmap_ino_bmbt_owner(&oinfo, sc->ip->i_ino, whichfork);
+ return xfs_repair_reap_btree_extents(sc, &rb.btlist, &oinfo,
+ XFS_AG_RESV_NONE);
+out:
+ xfs_repair_cancel_btree_extents(sc, &rb.btlist);
+ list_for_each_entry_safe(rbe, n, &rb.extlist, list) {
+ list_del(&rbe->list);
+ if (rbe != &rb.ext)
+ kmem_free(rbe);
+ }
+ return error;
+}
+
+/* Repair an inode's data fork. */
+int
+xfs_repair_bmap_data(
+ struct xfs_scrub_context *sc,
+ uint32_t scrub_oflags)
+{
+ return xfs_repair_bmap(sc, XFS_DATA_FORK);
+}
+
+/* Repair an inode's attr fork. */
+int
+xfs_repair_bmap_attr(
+ struct xfs_scrub_context *sc,
+ uint32_t scrub_oflags)
+{
+ return xfs_repair_bmap(sc, XFS_ATTR_FORK);
+}
diff --git a/fs/xfs/scrub/repair.h b/fs/xfs/scrub/repair.h
index 0fbc8f8..1c5d562 100644
--- a/fs/xfs/scrub/repair.h
+++ b/fs/xfs/scrub/repair.h
@@ -122,6 +122,8 @@ int xfs_repair_iallocbt(struct xfs_scrub_context *sc, uint32_t scrub_oflags);
int xfs_repair_rmapbt(struct xfs_scrub_context *sc, uint32_t scrub_oflags);
int xfs_repair_refcountbt(struct xfs_scrub_context *sc, uint32_t scrub_oflags);
int xfs_repair_inode(struct xfs_scrub_context *sc, uint32_t scrub_oflags);
+int xfs_repair_bmap_data(struct xfs_scrub_context *sc, uint32_t scrub_oflags);
+int xfs_repair_bmap_attr(struct xfs_scrub_context *sc, uint32_t scrub_oflags);
#else
@@ -155,6 +157,8 @@ xfs_repair_calc_ag_resblks(
# define xfs_repair_fs_thaw xfs_repair_fail
# define xfs_repair_refcountbt (NULL)
# define xfs_repair_inode (NULL)
+# define xfs_repair_bmap_data (NULL)
+# define xfs_repair_bmap_attr (NULL)
#endif /* IS_ENABLED(CONFIG_XFS_ONLINE_REPAIR) */
diff --git a/fs/xfs/scrub/scrub.c b/fs/xfs/scrub/scrub.c
index e167afe..2a3a292 100644
--- a/fs/xfs/scrub/scrub.c
+++ b/fs/xfs/scrub/scrub.c
@@ -291,11 +291,13 @@ static const struct xfs_scrub_meta_ops meta_scrub_ops[] = {
.type = ST_INODE,
.setup = xfs_scrub_setup_inode_bmap,
.scrub = xfs_scrub_bmap_data,
+ .repair = xfs_repair_bmap_data,
},
[XFS_SCRUB_TYPE_BMBTA] = { /* inode attr fork */
.type = ST_INODE,
.setup = xfs_scrub_setup_inode_bmap,
.scrub = xfs_scrub_bmap_attr,
+ .repair = xfs_repair_bmap_attr,
},
[XFS_SCRUB_TYPE_BMBTC] = { /* inode CoW fork */
.type = ST_INODE,
diff --git a/fs/xfs/xfs_trans.c b/fs/xfs/xfs_trans.c
index 86f92df..e961435 100644
--- a/fs/xfs/xfs_trans.c
+++ b/fs/xfs/xfs_trans.c
@@ -132,6 +132,60 @@ xfs_trans_dup(
}
/*
+ * Try to reserve more blocks for a transaction. The single use case we
+ * support is for online repair -- use a transaction to gather data without
+ * fear of btree cycle deadlocks; calculate how many blocks we really need
+ * from that data; and only then start modifying data. This can fail due to
+ * ENOSPC, so we have to be able to cancel the transaction.
+ */
+int
+xfs_trans_reserve_more(
+ struct xfs_trans *tp,
+ uint blocks,
+ uint rtextents)
+{
+ struct xfs_mount *mp = tp->t_mountp;
+ bool rsvd = (tp->t_flags & XFS_TRANS_RESERVE) != 0;
+ int error = 0;
+
+ ASSERT(!(tp->t_flags & XFS_TRANS_DIRTY));
+
+ /*
+ * Attempt to reserve the needed disk blocks by decrementing
+ * the number needed from the number available. This will
+ * fail if the count would go below zero.
+ */
+ if (blocks > 0) {
+ error = xfs_mod_fdblocks(mp, -((int64_t)blocks), rsvd);
+ if (error != 0)
+ return -ENOSPC;
+ tp->t_blk_res += blocks;
+ }
+
+ /*
+ * Attempt to reserve the needed realtime extents by decrementing
+ * the number needed from the number available. This will
+ * fail if the count would go below zero.
+ */
+ if (rtextents > 0) {
+ error = xfs_mod_frextents(mp, -((int64_t)rtextents));
+ if (error) {
+ error = -ENOSPC;
+ goto out_blocks;
+ }
+ tp->t_rtx_res += rtextents;
+ }
+
+ return 0;
+out_blocks:
+ if (blocks > 0) {
+ xfs_mod_fdblocks(mp, (int64_t)blocks, rsvd);
+ tp->t_blk_res -= blocks;
+ }
+ return error;
+}
+
+/*
* This is called to reserve free disk blocks and log space for the
* given transaction. This must be done before allocating any resources
* within the transaction.
diff --git a/fs/xfs/xfs_trans.h b/fs/xfs/xfs_trans.h
index 9d542df..1dcf8e2 100644
--- a/fs/xfs/xfs_trans.h
+++ b/fs/xfs/xfs_trans.h
@@ -158,6 +158,8 @@ typedef struct xfs_trans {
int xfs_trans_alloc(struct xfs_mount *mp, struct xfs_trans_res *resp,
uint blocks, uint rtextents, uint flags,
struct xfs_trans **tpp);
+int xfs_trans_reserve_more(struct xfs_trans *tp, uint blocks,
+ uint rtextents);
int xfs_trans_alloc_empty(struct xfs_mount *mp,
struct xfs_trans **tpp);
void xfs_trans_mod_sb(xfs_trans_t *, uint, int64_t);
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