diff options
| -rw-r--r-- | fs/xfs/xfs_bmap_util.c | 81 |
1 files changed, 37 insertions, 44 deletions
diff --git a/fs/xfs/xfs_bmap_util.c b/fs/xfs/xfs_bmap_util.c index 5d29aa17475e..8f7da5877fa3 100644 --- a/fs/xfs/xfs_bmap_util.c +++ b/fs/xfs/xfs_bmap_util.c @@ -1672,6 +1672,30 @@ xfs_swap_extents_check_format( } int +xfs_swap_extent_flush( + struct xfs_inode *ip) +{ + int error; + + error = filemap_write_and_wait(VFS_I(ip)->i_mapping); + if (error) + return error; + truncate_pagecache_range(VFS_I(ip), 0, -1); + + /* Verify O_DIRECT for ftmp */ + if (VFS_I(ip)->i_mapping->nrpages) + return -EINVAL; + + /* + * Don't try to swap extents on mmap()d files because we can't lock + * out races against page faults safely. + */ + if (mapping_mapped(VFS_I(ip)->i_mapping)) + return -EBUSY; + return 0; +} + +int xfs_swap_extents( xfs_inode_t *ip, /* target inode */ xfs_inode_t *tip, /* tmp inode */ @@ -1715,26 +1739,28 @@ xfs_swap_extents( goto out_unlock; } - error = filemap_write_and_wait(VFS_I(tip)->i_mapping); + error = xfs_swap_extent_flush(ip); + if (error) + goto out_unlock; + error = xfs_swap_extent_flush(tip); if (error) goto out_unlock; - truncate_pagecache_range(VFS_I(tip), 0, -1); - - xfs_lock_two_inodes(ip, tip, XFS_ILOCK_EXCL); - lock_flags |= XFS_ILOCK_EXCL; - /* Verify O_DIRECT for ftmp */ - if (VFS_I(tip)->i_mapping->nrpages) { - error = -EINVAL; + tp = xfs_trans_alloc(mp, XFS_TRANS_SWAPEXT); + error = xfs_trans_reserve(tp, &M_RES(mp)->tr_ichange, 0, 0); + if (error) { + xfs_trans_cancel(tp, 0); goto out_unlock; } + xfs_lock_two_inodes(ip, tip, XFS_ILOCK_EXCL); + lock_flags |= XFS_ILOCK_EXCL; /* Verify all data are being swapped */ if (sxp->sx_offset != 0 || sxp->sx_length != ip->i_d.di_size || sxp->sx_length != tip->i_d.di_size) { error = -EFAULT; - goto out_unlock; + goto out_trans_cancel; } trace_xfs_swap_extent_before(ip, 0); @@ -1746,7 +1772,7 @@ xfs_swap_extents( xfs_notice(mp, "%s: inode 0x%llx format is incompatible for exchanging.", __func__, ip->i_ino); - goto out_unlock; + goto out_trans_cancel; } /* @@ -1761,41 +1787,8 @@ xfs_swap_extents( (sbp->bs_mtime.tv_sec != VFS_I(ip)->i_mtime.tv_sec) || (sbp->bs_mtime.tv_nsec != VFS_I(ip)->i_mtime.tv_nsec)) { error = -EBUSY; - goto out_unlock; - } - - /* We need to fail if the file is memory mapped. Once we have tossed - * all existing pages, the page fault will have no option - * but to go to the filesystem for pages. By making the page fault call - * vop_read (or write in the case of autogrow) they block on the iolock - * until we have switched the extents. - */ - if (mapping_mapped(VFS_I(ip)->i_mapping)) { - error = -EBUSY; - goto out_unlock; - } - - xfs_iunlock(ip, XFS_ILOCK_EXCL); - xfs_iunlock(tip, XFS_ILOCK_EXCL); - lock_flags &= ~XFS_ILOCK_EXCL; - - /* - * There is a race condition here since we gave up the - * ilock. However, the data fork will not change since - * we have the iolock (locked for truncation too) so we - * are safe. We don't really care if non-io related - * fields change. - */ - truncate_pagecache_range(VFS_I(ip), 0, -1); - - tp = xfs_trans_alloc(mp, XFS_TRANS_SWAPEXT); - error = xfs_trans_reserve(tp, &M_RES(mp)->tr_ichange, 0, 0); - if (error) goto out_trans_cancel; - - xfs_lock_two_inodes(ip, tip, XFS_ILOCK_EXCL); - lock_flags |= XFS_ILOCK_EXCL; - + } /* * Count the number of extended attribute blocks */ |