diff options
author | Dave Chinner <dchinner@redhat.com> | 2015-06-04 09:18:18 +1000 |
---|---|---|
committer | Ben Hutchings <ben@decadent.org.uk> | 2016-06-15 21:29:33 +0100 |
commit | a80de2c9dd4c7c129813f9c70853bf97c0372ea0 (patch) | |
tree | 0b45d90b4a65d4816b5ce427f219d43fb45600bb /fs | |
parent | 7cafecfabbd7119ca94bd5583411ff245bcbbaec (diff) |
xfs: mmap lock needs to be inside freeze protection
commit ec56b1f1fdc69599963574ce94cc5693d535dd64 upstream.
Lock ordering for the new mmap lock needs to be:
mmap_sem
sb_start_pagefault
i_mmap_lock
page lock
<fault processsing>
Right now xfs_vm_page_mkwrite gets this the wrong way around,
While technically it cannot deadlock due to the current freeze
ordering, it's still a landmine that might explode if we change
anything in future. Hence we need to nest the locks correctly.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Jan Kara <jack@suse.cz>
Cc: xfs@oss.sgi.com
Diffstat (limited to 'fs')
-rw-r--r-- | fs/xfs/xfs_file.c | 11 |
1 files changed, 8 insertions, 3 deletions
diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c index 975aaac7494e..d2f4cb598b46 100644 --- a/fs/xfs/xfs_file.c +++ b/fs/xfs/xfs_file.c @@ -1441,15 +1441,20 @@ xfs_filemap_page_mkwrite( struct vm_fault *vmf) { struct xfs_inode *ip = XFS_I(vma->vm_file->f_mapping->host); - int error; + int ret; trace_xfs_filemap_page_mkwrite(ip); + sb_start_pagefault(VFS_I(ip)->i_sb); + file_update_time(vma->vm_file); xfs_ilock(ip, XFS_MMAPLOCK_SHARED); - error = block_page_mkwrite(vma, vmf, xfs_get_blocks); + + ret = __block_page_mkwrite(vma, vmf, xfs_get_blocks); + xfs_iunlock(ip, XFS_MMAPLOCK_SHARED); + sb_end_pagefault(VFS_I(ip)->i_sb); - return error; + return block_page_mkwrite_return(ret); } const struct file_operations xfs_file_operations = { |