From: "Darrick J. Wong" <darrick.wong@oracle.com>
To: darrick.wong@oracle.com
Cc: linux-xfs@vger.kernel.org
Subject: [PATCH 19/19] xfs: repair damaged symlinks
Date: Fri, 25 Aug 2017 15:18:57 -0700 [thread overview]
Message-ID: <150369953779.9957.12358688240803030326.stgit@magnolia> (raw)
In-Reply-To: <150369940879.9957.6303798184036268321.stgit@magnolia>
From: Darrick J. Wong <darrick.wong@oracle.com>
Repair inconsistent symbolic link data.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
fs/xfs/scrub/repair.h | 1
fs/xfs/scrub/scrub.c | 1
fs/xfs/scrub/symlink.c | 238 ++++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 239 insertions(+), 1 deletion(-)
diff --git a/fs/xfs/scrub/repair.h b/fs/xfs/scrub/repair.h
index a56f2bc..aee17e0 100644
--- a/fs/xfs/scrub/repair.h
+++ b/fs/xfs/scrub/repair.h
@@ -84,5 +84,6 @@ int xfs_repair_refcountbt(struct xfs_scrub_context *sc);
int xfs_repair_inode(struct xfs_scrub_context *sc);
int xfs_repair_bmap_data(struct xfs_scrub_context *sc);
int xfs_repair_bmap_attr(struct xfs_scrub_context *sc);
+int xfs_repair_symlink(struct xfs_scrub_context *sc);
#endif /* __XFS_SCRUB_REPAIR_H__ */
diff --git a/fs/xfs/scrub/scrub.c b/fs/xfs/scrub/scrub.c
index 79dc9f9..7f9a4f8 100644
--- a/fs/xfs/scrub/scrub.c
+++ b/fs/xfs/scrub/scrub.c
@@ -304,6 +304,7 @@ static const struct xfs_scrub_meta_ops meta_scrub_ops[] = {
{ /* symbolic link */
.setup = xfs_scrub_setup_symlink,
.scrub = xfs_scrub_symlink,
+ .repair = xfs_repair_symlink,
},
{ /* parent pointers */
.setup = xfs_scrub_setup_parent,
diff --git a/fs/xfs/scrub/symlink.c b/fs/xfs/scrub/symlink.c
index e3b5d35..35c0071 100644
--- a/fs/xfs/scrub/symlink.c
+++ b/fs/xfs/scrub/symlink.c
@@ -32,10 +32,13 @@
#include "xfs_inode.h"
#include "xfs_inode_fork.h"
#include "xfs_symlink.h"
+#include "xfs_bmap.h"
+#include "xfs_quota.h"
#include "scrub/xfs_scrub.h"
#include "scrub/scrub.h"
#include "scrub/common.h"
#include "scrub/trace.h"
+#include "scrub/repair.h"
/* Set us up to scrub a symbolic link. */
int
@@ -48,7 +51,7 @@ xfs_scrub_setup_symlink(
if (!sc->buf)
return -ENOMEM;
- return xfs_scrub_setup_inode_contents(sc, ip, 0);
+ return xfs_scrub_setup_inode_contents(sc, ip, XFS_SYMLINK_MAPS);
}
/* Symbolic links. */
@@ -90,3 +93,236 @@ xfs_scrub_symlink(
out:
return error;
}
+
+/* Blow out the whole symlink; replace contents. */
+STATIC int
+xfs_repair_symlink_rewrite(
+ struct xfs_trans **tpp,
+ struct xfs_inode *ip,
+ const char *target_path,
+ int pathlen)
+{
+ struct xfs_defer_ops dfops;
+ struct xfs_bmbt_irec mval[XFS_SYMLINK_MAPS];
+ struct xfs_ifork *ifp;
+ const char *cur_chunk;
+ struct xfs_mount *mp = (*tpp)->t_mountp;
+ struct xfs_buf *bp;
+ xfs_fsblock_t first_block;
+ xfs_fileoff_t first_fsb;
+ xfs_filblks_t fs_blocks;
+ xfs_daddr_t d;
+ uint resblks;
+ int byte_cnt;
+ int n;
+ int nmaps;
+ int offset;
+ int error = 0;
+
+ ifp = XFS_IFORK_PTR(ip, XFS_DATA_FORK);
+
+ /* Truncate the whole data fork if it wasn't inline. */
+ if (!(ifp->if_flags & XFS_IFINLINE)) {
+ error = xfs_itruncate_extents(tpp, ip, XFS_DATA_FORK, 0);
+ if (error)
+ goto out;
+ }
+
+ /* Blow out the in-core fork and zero the on-disk fork. */
+ xfs_idestroy_fork(ip, XFS_DATA_FORK);
+ ip->i_d.di_format = XFS_DINODE_FMT_EXTENTS;
+ ip->i_d.di_nextents = 0;
+ memset(&ip->i_df, 0, sizeof(struct xfs_ifork));
+ ip->i_df.if_flags |= XFS_IFEXTENTS;
+
+ /* Rewrite an inline symlink. */
+ if (pathlen <= XFS_IFORK_DSIZE(ip)) {
+ xfs_init_local_fork(ip, XFS_DATA_FORK, target_path, pathlen);
+
+ i_size_write(VFS_I(ip), pathlen);
+ ip->i_d.di_size = pathlen;
+ ip->i_d.di_format = XFS_DINODE_FMT_LOCAL;
+ xfs_trans_log_inode(*tpp, ip, XFS_ILOG_DDATA | XFS_ILOG_CORE);
+ goto out;
+
+ }
+
+ /* Rewrite a remote symlink. */
+ fs_blocks = xfs_symlink_blocks(mp, pathlen);
+ first_fsb = 0;
+ nmaps = XFS_SYMLINK_MAPS;
+
+ /* Reserve quota for new blocks. */
+ error = xfs_trans_reserve_quota_nblks(*tpp, ip, fs_blocks, 0,
+ XFS_QMOPT_RES_REGBLKS);
+ if (error)
+ goto out;
+
+ /* Map blocks, write symlink target. */
+ xfs_defer_init(&dfops, &first_block);
+
+ error = xfs_bmapi_write(*tpp, ip, first_fsb, fs_blocks,
+ XFS_BMAPI_METADATA, &first_block, fs_blocks,
+ mval, &nmaps, &dfops);
+ if (error)
+ goto out_bmap_cancel;
+
+ if (resblks)
+ resblks -= fs_blocks;
+ ip->i_d.di_size = pathlen;
+ i_size_write(VFS_I(ip), pathlen);
+ xfs_trans_log_inode(*tpp, ip, XFS_ILOG_CORE);
+
+ cur_chunk = target_path;
+ offset = 0;
+ for (n = 0; n < nmaps; n++) {
+ char *buf;
+
+ d = XFS_FSB_TO_DADDR(mp, mval[n].br_startblock);
+ byte_cnt = XFS_FSB_TO_B(mp, mval[n].br_blockcount);
+ bp = xfs_trans_get_buf(*tpp, mp->m_ddev_targp, d,
+ BTOBB(byte_cnt), 0);
+ if (!bp) {
+ error = -ENOMEM;
+ goto out_bmap_cancel;
+ }
+ bp->b_ops = &xfs_symlink_buf_ops;
+
+ byte_cnt = XFS_SYMLINK_BUF_SPACE(mp, byte_cnt);
+ byte_cnt = min(byte_cnt, pathlen);
+
+ buf = bp->b_addr;
+ buf += xfs_symlink_hdr_set(mp, ip->i_ino, offset,
+ byte_cnt, bp);
+
+ memcpy(buf, cur_chunk, byte_cnt);
+
+ cur_chunk += byte_cnt;
+ pathlen -= byte_cnt;
+ offset += byte_cnt;
+
+ xfs_trans_buf_set_type(*tpp, bp, XFS_BLFT_SYMLINK_BUF);
+ xfs_trans_log_buf(*tpp, bp, 0, (buf + byte_cnt - 1) -
+ (char *)bp->b_addr);
+ }
+ ASSERT(pathlen == 0);
+
+ error = xfs_defer_finish(tpp, &dfops, NULL);
+ if (error)
+ goto out_bmap_cancel;
+
+ return 0;
+
+out_bmap_cancel:
+ xfs_defer_cancel(&dfops);
+out:
+ return error;
+}
+
+int
+xfs_repair_symlink(
+ struct xfs_scrub_context *sc)
+{
+ struct xfs_bmbt_irec mval[XFS_SYMLINK_MAPS];
+ struct xfs_inode *ip = sc->ip;
+ struct xfs_mount *mp = sc->mp;
+ struct xfs_ifork *ifp;
+ struct xfs_buf *bp;
+ loff_t len;
+ size_t newlen;
+ xfs_daddr_t d;
+ int fsblocks;
+ int nmaps = XFS_SYMLINK_MAPS;
+ int nr;
+ int offset;
+ int n;
+ int byte_cnt;
+ int error = 0;
+
+ ifp = XFS_IFORK_PTR(ip, XFS_DATA_FORK);
+ len = i_size_read(VFS_I(ip));
+ xfs_trans_ijoin(sc->tp, ip, 0);
+
+ /* Truncate the inode if there's a zero inside the length. */
+ if (ifp->if_flags & XFS_IFINLINE) {
+ if (ifp->if_u1.if_data)
+ newlen = strnlen(ifp->if_u1.if_data,
+ XFS_IFORK_DSIZE(ip));
+ else {
+ newlen = 1;
+ ifp->if_u1.if_data = ifp->if_u2.if_inline_data;
+ ifp->if_u1.if_data[0] = '/';
+ }
+ if (len > newlen) {
+ i_size_write(VFS_I(ip), newlen);
+ ip->i_d.di_size = newlen;
+ xfs_trans_log_inode(sc->tp, ip, XFS_ILOG_DDATA |
+ XFS_ILOG_CORE);
+ }
+ goto out;
+ }
+
+ fsblocks = xfs_symlink_blocks(mp, len);
+ error = xfs_bmapi_read(ip, 0, fsblocks, mval, &nmaps, 0);
+ if (error)
+ goto out;
+
+ /* Fix everything that fails the verifiers. */
+ offset = 0;
+ for (n = 0; n < nmaps; n++) {
+ d = XFS_FSB_TO_DADDR(mp, mval[n].br_startblock);
+ byte_cnt = XFS_FSB_TO_B(mp, mval[n].br_blockcount);
+
+ error = xfs_trans_read_buf(mp, sc->tp, mp->m_ddev_targp,
+ d, BTOBB(byte_cnt), 0, &bp, NULL);
+ if (error)
+ goto out;
+ bp->b_ops = &xfs_symlink_buf_ops;
+
+ byte_cnt = XFS_SYMLINK_BUF_SPACE(mp, byte_cnt);
+ if (len < byte_cnt)
+ byte_cnt = len;
+
+ nr = xfs_symlink_hdr_set(mp, ip->i_ino, offset, byte_cnt, bp);
+
+ len -= byte_cnt;
+ offset += byte_cnt;
+
+ xfs_trans_buf_set_type(sc->tp, bp, XFS_BLFT_SYMLINK_BUF);
+ xfs_trans_log_buf(sc->tp, bp, 0, nr - 1);
+ xfs_trans_brelse(sc->tp, bp);
+ }
+ if (len != 0) {
+ error = -EFSCORRUPTED;
+ goto out;
+ }
+
+ /* Roll transaction, release buffers. */
+ error = xfs_trans_roll(&sc->tp, ip);
+ if (error)
+ goto out;
+
+ /* Size set correctly? */
+ len = i_size_read(VFS_I(ip));
+ xfs_iunlock(ip, XFS_ILOCK_EXCL);
+ error = xfs_readlink(ip, sc->buf);
+ xfs_ilock(ip, XFS_ILOCK_EXCL);
+ if (error)
+ goto out;
+
+ /*
+ * Figure out the new target length. We can't handle zero-length
+ * symlinks, so make sure that we don't write that out.
+ */
+ newlen = strnlen(sc->buf, XFS_SYMLINK_MAXLEN);
+ if (newlen == 0) {
+ *((char *)sc->buf) = '/';
+ newlen = 1;
+ }
+
+ if (len > newlen)
+ error = xfs_repair_symlink_rewrite(&sc->tp, ip, sc->buf,
+ newlen);
+out:
+ return error;
+}
prev parent reply other threads:[~2017-08-25 22:19 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-08-25 22:16 [PATCH v9 00/19] xfs: online fs repair support Darrick J. Wong
2017-08-25 22:16 ` [PATCH 01/19] xfs: add helpers to calculate btree size Darrick J. Wong
2017-08-25 22:17 ` [PATCH 02/19] xfs: expose various functions to repair code Darrick J. Wong
2017-08-25 22:17 ` [PATCH 03/19] xfs: add repair helpers for the reverse mapping btree Darrick J. Wong
2017-08-25 22:17 ` [PATCH 04/19] xfs: add repair helpers for the reference count btree Darrick J. Wong
2017-08-25 22:17 ` [PATCH 05/19] xfs: add BMAPI_NORMAP flag to perform block remapping without updating rmpabt Darrick J. Wong
2017-08-25 22:17 ` [PATCH 06/19] xfs: halt auto-reclamation activities while rebuilding rmap Darrick J. Wong
2017-08-25 22:17 ` [PATCH 07/19] xfs: create tracepoints for online repair Darrick J. Wong
2017-08-25 22:17 ` [PATCH 08/19] xfs: implement the metadata repair ioctl flag Darrick J. Wong
2017-08-25 22:17 ` [PATCH 09/19] xfs: add helper routines for the repair code Darrick J. Wong
2017-08-25 22:17 ` [PATCH 10/19] xfs: repair superblocks Darrick J. Wong
2017-08-25 22:18 ` [PATCH 11/19] xfs: repair the AGF and AGFL Darrick J. Wong
2017-08-25 22:18 ` [PATCH 12/19] xfs: rebuild the AGI Darrick J. Wong
2017-08-25 22:18 ` [PATCH 13/19] xfs: repair free space btrees Darrick J. Wong
2017-08-25 22:18 ` [PATCH 14/19] xfs: repair inode btrees Darrick J. Wong
2017-08-25 22:18 ` [PATCH 15/19] xfs: rebuild the rmapbt Darrick J. Wong
2017-08-25 22:18 ` [PATCH 16/19] xfs: repair refcount btrees Darrick J. Wong
2017-08-25 22:18 ` [PATCH 17/19] xfs: online repair of inodes Darrick J. Wong
2017-08-25 22:18 ` [PATCH 18/19] xfs: repair inode block maps Darrick J. Wong
2017-08-25 22:18 ` Darrick J. Wong [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=150369953779.9957.12358688240803030326.stgit@magnolia \
--to=darrick.wong@oracle.com \
--cc=linux-xfs@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).