diff options
author | Dave Chinner <david@fromorbit.com> | 2014-08-04 07:55:27 +0400 |
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committer | Dave Chinner <david@fromorbit.com> | 2014-08-04 07:55:27 +0400 |
commit | 645f9857213476407d8ed1b59619fdff7128d3e6 (patch) | |
tree | f48e76ffa8b4af8bfa0c64d54ff96d76b61f6f65 /fs/xfs/xfs_bmap_util.c | |
parent | b076d8720d793cde04b75b4941b8774e209649b4 (diff) | |
parent | 4ef897a27543b513351262881660147366c042a1 (diff) | |
download | linux-645f9857213476407d8ed1b59619fdff7128d3e6.tar.xz |
Merge branch 'xfs-misc-fixes-3.17-2' into for-next
Diffstat (limited to 'fs/xfs/xfs_bmap_util.c')
-rw-r--r-- | fs/xfs/xfs_bmap_util.c | 100 |
1 files changed, 48 insertions, 52 deletions
diff --git a/fs/xfs/xfs_bmap_util.c b/fs/xfs/xfs_bmap_util.c index d32889af1777..2f1e30d39a35 100644 --- a/fs/xfs/xfs_bmap_util.c +++ b/fs/xfs/xfs_bmap_util.c @@ -809,7 +809,7 @@ xfs_can_free_eofblocks(struct xfs_inode *ip, bool force) * have speculative prealloc/delalloc blocks to remove. */ if (VFS_I(ip)->i_size == 0 && - VN_CACHED(VFS_I(ip)) == 0 && + VFS_I(ip)->i_mapping->nrpages == 0 && ip->i_delayed_blks == 0) return false; @@ -1619,6 +1619,30 @@ 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 */ @@ -1633,6 +1657,7 @@ xfs_swap_extents( int aforkblks = 0; int taforkblks = 0; __uint64_t tmp; + int lock_flags; tempifp = kmem_alloc(sizeof(xfs_ifork_t), KM_MAYFAIL); if (!tempifp) { @@ -1641,13 +1666,13 @@ xfs_swap_extents( } /* - * we have to do two separate lock calls here to keep lockdep - * happy. If we try to get all the locks in one call, lock will - * report false positives when we drop the ILOCK and regain them - * below. + * Lock up the inodes against other IO and truncate to begin with. + * Then we can ensure the inodes are flushed and have no page cache + * safely. Once we have done this we can take the ilocks and do the rest + * of the checks. */ + lock_flags = XFS_IOLOCK_EXCL; xfs_lock_two_inodes(ip, tip, XFS_IOLOCK_EXCL); - xfs_lock_two_inodes(ip, tip, XFS_ILOCK_EXCL); /* Verify that both files have the same format */ if ((ip->i_d.di_mode & S_IFMT) != (tip->i_d.di_mode & S_IFMT)) { @@ -1661,23 +1686,28 @@ 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); - /* Verify O_DIRECT for ftmp */ - if (VN_CACHED(VFS_I(tip)) != 0) { - 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); @@ -1689,7 +1719,7 @@ 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; } /* @@ -1704,42 +1734,8 @@ 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 (VN_MAPPED(VFS_I(ip))) { - error = -EBUSY; - goto out_unlock; - } - - xfs_iunlock(ip, XFS_ILOCK_EXCL); - xfs_iunlock(tip, 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) { - xfs_iunlock(ip, XFS_IOLOCK_EXCL); - xfs_iunlock(tip, XFS_IOLOCK_EXCL); - xfs_trans_cancel(tp, 0); - goto out; + goto out_trans_cancel; } - xfs_lock_two_inodes(ip, tip, XFS_ILOCK_EXCL); - /* * Count the number of extended attribute blocks */ @@ -1757,8 +1753,8 @@ xfs_swap_extents( goto out_trans_cancel; } - xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL | XFS_IOLOCK_EXCL); - xfs_trans_ijoin(tp, tip, XFS_ILOCK_EXCL | XFS_IOLOCK_EXCL); + xfs_trans_ijoin(tp, ip, lock_flags); + xfs_trans_ijoin(tp, tip, lock_flags); /* * Before we've swapped the forks, lets set the owners of the forks @@ -1887,8 +1883,8 @@ out: return error; out_unlock: - xfs_iunlock(ip, XFS_ILOCK_EXCL | XFS_IOLOCK_EXCL); - xfs_iunlock(tip, XFS_ILOCK_EXCL | XFS_IOLOCK_EXCL); + xfs_iunlock(ip, lock_flags); + xfs_iunlock(tip, lock_flags); goto out; out_trans_cancel: |