From d2c292d84c4983424938f32c9c247f6ab8719769 Mon Sep 17 00:00:00 2001 From: Jan Kara Date: Mon, 24 May 2021 13:17:49 +0200 Subject: [PATCH] xfs: Convert double locking of MMAPLOCK to use VFS helpers Convert places in XFS that take MMAPLOCK for two inodes to use helper VFS provides for it (filemap_invalidate_down_write_two()). Note that this changes lock ordering for MMAPLOCK from inode number based ordering to pointer based ordering VFS generally uses. CC: "Darrick J. Wong" Reviewed-by: Darrick J. Wong Reviewed-by: Christoph Hellwig Signed-off-by: Jan Kara --- fs/xfs/xfs_bmap_util.c | 15 ++++++++------- fs/xfs/xfs_inode.c | 37 +++++++++++-------------------------- 2 files changed, 19 insertions(+), 33 deletions(-) diff --git a/fs/xfs/xfs_bmap_util.c b/fs/xfs/xfs_bmap_util.c index 213a97a..1cd3f94 100644 --- a/fs/xfs/xfs_bmap_util.c +++ b/fs/xfs/xfs_bmap_util.c @@ -1626,7 +1626,6 @@ xfs_swap_extents( struct xfs_bstat *sbp = &sxp->sx_stat; int src_log_flags, target_log_flags; int error = 0; - int lock_flags; uint64_t f; int resblks = 0; unsigned int flags = 0; @@ -1638,8 +1637,8 @@ xfs_swap_extents( * do the rest of the checks. */ lock_two_nondirectories(VFS_I(ip), VFS_I(tip)); - lock_flags = XFS_MMAPLOCK_EXCL; - xfs_lock_two_inodes(ip, XFS_MMAPLOCK_EXCL, tip, XFS_MMAPLOCK_EXCL); + filemap_invalidate_lock_two(VFS_I(ip)->i_mapping, + VFS_I(tip)->i_mapping); /* Verify that both files have the same format */ if ((VFS_I(ip)->i_mode & S_IFMT) != (VFS_I(tip)->i_mode & S_IFMT)) { @@ -1711,7 +1710,6 @@ xfs_swap_extents( * or cancel will unlock the inodes from this point onwards. */ xfs_lock_two_inodes(ip, XFS_ILOCK_EXCL, tip, XFS_ILOCK_EXCL); - lock_flags |= XFS_ILOCK_EXCL; xfs_trans_ijoin(tp, ip, 0); xfs_trans_ijoin(tp, tip, 0); @@ -1830,13 +1828,16 @@ xfs_swap_extents( trace_xfs_swap_extent_after(ip, 0); trace_xfs_swap_extent_after(tip, 1); +out_unlock_ilock: + xfs_iunlock(ip, XFS_ILOCK_EXCL); + xfs_iunlock(tip, XFS_ILOCK_EXCL); out_unlock: - xfs_iunlock(ip, lock_flags); - xfs_iunlock(tip, lock_flags); + filemap_invalidate_unlock_two(VFS_I(ip)->i_mapping, + VFS_I(tip)->i_mapping); unlock_two_nondirectories(VFS_I(ip), VFS_I(tip)); return error; out_trans_cancel: xfs_trans_cancel(tp); - goto out_unlock; + goto out_unlock_ilock; } diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c index d6a8ac7..3c0bb21 100644 --- a/fs/xfs/xfs_inode.c +++ b/fs/xfs/xfs_inode.c @@ -552,12 +552,10 @@ again: } /* - * xfs_lock_two_inodes() can only be used to lock one type of lock at a time - - * the mmaplock or the ilock, but not more than one type at a time. If we lock - * more than one at a time, lockdep will report false positives saying we have - * violated locking orders. The iolock must be double-locked separately since - * we use i_rwsem for that. We now support taking one lock EXCL and the other - * SHARED. + * xfs_lock_two_inodes() can only be used to lock ilock. The iolock and + * mmaplock must be double-locked separately since we use i_rwsem and + * invalidate_lock for that. We now support taking one lock EXCL and the + * other SHARED. */ void xfs_lock_two_inodes( @@ -575,15 +573,8 @@ xfs_lock_two_inodes( ASSERT(hweight32(ip1_mode) == 1); ASSERT(!(ip0_mode & (XFS_IOLOCK_SHARED|XFS_IOLOCK_EXCL))); ASSERT(!(ip1_mode & (XFS_IOLOCK_SHARED|XFS_IOLOCK_EXCL))); - ASSERT(!(ip0_mode & (XFS_MMAPLOCK_SHARED|XFS_MMAPLOCK_EXCL)) || - !(ip0_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL))); - ASSERT(!(ip1_mode & (XFS_MMAPLOCK_SHARED|XFS_MMAPLOCK_EXCL)) || - !(ip1_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL))); - ASSERT(!(ip1_mode & (XFS_MMAPLOCK_SHARED|XFS_MMAPLOCK_EXCL)) || - !(ip0_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL))); - ASSERT(!(ip0_mode & (XFS_MMAPLOCK_SHARED|XFS_MMAPLOCK_EXCL)) || - !(ip1_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL))); - + ASSERT(!(ip0_mode & (XFS_MMAPLOCK_SHARED|XFS_MMAPLOCK_EXCL))); + ASSERT(!(ip1_mode & (XFS_MMAPLOCK_SHARED|XFS_MMAPLOCK_EXCL))); ASSERT(ip0->i_ino != ip1->i_ino); if (ip0->i_ino > ip1->i_ino) { @@ -3748,11 +3739,8 @@ xfs_ilock2_io_mmap( ret = xfs_iolock_two_inodes_and_break_layout(VFS_I(ip1), VFS_I(ip2)); if (ret) return ret; - if (ip1 == ip2) - xfs_ilock(ip1, XFS_MMAPLOCK_EXCL); - else - xfs_lock_two_inodes(ip1, XFS_MMAPLOCK_EXCL, - ip2, XFS_MMAPLOCK_EXCL); + filemap_invalidate_lock_two(VFS_I(ip1)->i_mapping, + VFS_I(ip2)->i_mapping); return 0; } @@ -3762,12 +3750,9 @@ xfs_iunlock2_io_mmap( struct xfs_inode *ip1, struct xfs_inode *ip2) { - bool same_inode = (ip1 == ip2); - - xfs_iunlock(ip2, XFS_MMAPLOCK_EXCL); - if (!same_inode) - xfs_iunlock(ip1, XFS_MMAPLOCK_EXCL); + filemap_invalidate_unlock_two(VFS_I(ip1)->i_mapping, + VFS_I(ip2)->i_mapping); inode_unlock(VFS_I(ip2)); - if (!same_inode) + if (ip1 != ip2) inode_unlock(VFS_I(ip1)); } -- 2.7.4