From 5400da7dc0862d73523691038c044535f518a57f Mon Sep 17 00:00:00 2001 From: Brian Foster Date: Thu, 24 Jul 2014 19:40:22 +1000 Subject: [PATCH] xfs: add scan owner field to xfs_eofblocks From: Brian Foster The scan owner field represents an optional inode number that is responsible for the current scan. The purpose is to identify that an inode is under iolock and as such, the iolock shouldn't be attempted when trimming eofblocks. This is an internal only field. Signed-off-by: Brian Foster Reviewed-by: Dave Chinner Signed-off-by: Dave Chinner --- fs/xfs/xfs_icache.c | 13 ++++++++++++- fs/xfs/xfs_icache.h | 2 ++ 2 files changed, 14 insertions(+), 1 deletion(-) diff --git a/fs/xfs/xfs_icache.c b/fs/xfs/xfs_icache.c index 08ba4c6e1359..6e522ff5a006 100644 --- a/fs/xfs/xfs_icache.c +++ b/fs/xfs/xfs_icache.c @@ -1211,6 +1211,9 @@ xfs_inode_free_eofblocks( { int ret; struct xfs_eofblocks *eofb = args; + bool need_iolock = true; + + ASSERT(!eofb || (eofb && eofb->eof_scan_owner != 0)); if (!xfs_can_free_eofblocks(ip, false)) { /* inode could be preallocated or append-only */ @@ -1235,9 +1238,17 @@ xfs_inode_free_eofblocks( if (eofb->eof_flags & XFS_EOF_FLAGS_MINFILESIZE && XFS_ISIZE(ip) < eofb->eof_min_file_size) return 0; + + /* + * A scan owner implies we already hold the iolock. Skip it in + * xfs_free_eofblocks() to avoid deadlock. This also eliminates + * the possibility of EAGAIN being returned. + */ + if (eofb->eof_scan_owner == ip->i_ino) + need_iolock = false; } - ret = xfs_free_eofblocks(ip->i_mount, ip, true); + ret = xfs_free_eofblocks(ip->i_mount, ip, need_iolock); /* don't revisit the inode if we're not waiting */ if (ret == -EAGAIN && !(flags & SYNC_WAIT)) diff --git a/fs/xfs/xfs_icache.h b/fs/xfs/xfs_icache.h index 6250430d609c..98687af6a99d 100644 --- a/fs/xfs/xfs_icache.h +++ b/fs/xfs/xfs_icache.h @@ -27,6 +27,7 @@ struct xfs_eofblocks { kgid_t eof_gid; prid_t eof_prid; __u64 eof_min_file_size; + xfs_ino_t eof_scan_owner; }; #define SYNC_WAIT 0x0001 /* wait for i/o to complete */ @@ -84,6 +85,7 @@ xfs_fs_eofblocks_from_user( dst->eof_flags = src->eof_flags; dst->eof_prid = src->eof_prid; dst->eof_min_file_size = src->eof_min_file_size; + dst->eof_scan_owner = NULLFSINO; dst->eof_uid = INVALID_UID; if (src->eof_flags & XFS_EOF_FLAGS_UID) { -- 2.39.5