diff options
| author | Dave Chinner <dchinner@redhat.com> | 2015-11-03 12:37:02 +1100 |
|---|---|---|
| committer | Dave Chinner <david@fromorbit.com> | 2015-11-03 12:37:02 +1100 |
| commit | 13ad4fe3e087ab66a140f1e00d98f28aa4e3bb28 (patch) | |
| tree | e8f2cddd593803af2c6b8f6c31721ce7fe9d1fdb /fs/xfs/xfs_file.c | |
| parent | 3af49285854df66260a263198cc15abb07b95287 (diff) | |
xfs: xfs_filemap_pmd_fault treats read faults as write faults
The code initially committed didn't have the same checks for write
faults as the dax_pmd_fault code and hence treats all faults as
write faults. We can get read faults through this path because they
is no pmd_mkwrite path for write faults similar to the normal page
fault path. Hence we need to ensure that we only do c/mtime updates
on write faults, and freeze protection is unnecessary for read
faults.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Diffstat (limited to 'fs/xfs/xfs_file.c')
| -rw-r--r-- | fs/xfs/xfs_file.c | 20 |
1 files changed, 16 insertions, 4 deletions
diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c index f429662d7d42..ce208e3896aa 100644 --- a/fs/xfs/xfs_file.c +++ b/fs/xfs/xfs_file.c @@ -1477,7 +1477,7 @@ xfs_file_llseek( * * mmap_sem (MM) * sb_start_pagefault(vfs, freeze) - * i_mmap_lock (XFS - truncate serialisation) + * i_mmaplock (XFS - truncate serialisation) * page_lock (MM) * i_lock (XFS - extent map serialisation) */ @@ -1545,6 +1545,13 @@ xfs_filemap_fault( return ret; } +/* + * Similar to xfs_filemap_fault(), the DAX fault path can call into here on + * both read and write faults. Hence we need to handle both cases. There is no + * ->pmd_mkwrite callout for huge pages, so we have a single function here to + * handle both cases here. @flags carries the information on the type of fault + * occuring. + */ STATIC int xfs_filemap_pmd_fault( struct vm_area_struct *vma, @@ -1561,13 +1568,18 @@ xfs_filemap_pmd_fault( trace_xfs_filemap_pmd_fault(ip); - sb_start_pagefault(inode->i_sb); - file_update_time(vma->vm_file); + if (flags & FAULT_FLAG_WRITE) { + sb_start_pagefault(inode->i_sb); + file_update_time(vma->vm_file); + } + xfs_ilock(XFS_I(inode), XFS_MMAPLOCK_SHARED); ret = __dax_pmd_fault(vma, addr, pmd, flags, xfs_get_blocks_dax_fault, NULL); xfs_iunlock(XFS_I(inode), XFS_MMAPLOCK_SHARED); - sb_end_pagefault(inode->i_sb); + + if (flags & FAULT_FLAG_WRITE) + sb_end_pagefault(inode->i_sb); return ret; } |