diff options
| author | Dave Chinner <dchinner@redhat.com> | 2015-02-23 11:44:19 +0100 |
|---|---|---|
| committer | Dave Chinner <david@fromorbit.com> | 2015-02-23 11:44:19 +0100 |
| commit | de0e8c20ba3a65b0f15040aabbefdc1999876e6b (patch) | |
| tree | 1b727063b3d8c6a41e2ccb6a16f5f8134c566f09 /fs/xfs | |
| parent | xfs: introduce mmap/truncate lock (diff) | |
| download | linux-de0e8c20ba3a65b0f15040aabbefdc1999876e6b.tar.xz linux-de0e8c20ba3a65b0f15040aabbefdc1999876e6b.zip | |
xfs: use i_mmaplock on read faults
Take the i_mmaplock over read page faults. These come through the
->fault callout, so we need to wrap the generic implementation
with the i_mmaplock. While there, add tracepoints for the read
fault as it passes through XFS.
This gives us a lock order of mmap_sem -> i_mmaplock -> page_lock
-> i_lock.
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')
| -rw-r--r-- | fs/xfs/xfs_file.c | 28 | ||||
| -rw-r--r-- | fs/xfs/xfs_trace.h | 2 |
2 files changed, 29 insertions, 1 deletions
diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c index ce615d12fb44..ac174226244a 100644 --- a/fs/xfs/xfs_file.c +++ b/fs/xfs/xfs_file.c @@ -1379,6 +1379,32 @@ xfs_file_llseek( } } +/* + * Locking for serialisation of IO during page faults. This results in a lock + * ordering of: + * + * mmap_sem (MM) + * i_mmap_lock (XFS - truncate serialisation) + * page_lock (MM) + * i_lock (XFS - extent map serialisation) + */ +STATIC int +xfs_filemap_fault( + struct vm_area_struct *vma, + struct vm_fault *vmf) +{ + struct xfs_inode *ip = XFS_I(vma->vm_file->f_mapping->host); + int error; + + trace_xfs_filemap_fault(ip); + + xfs_ilock(ip, XFS_MMAPLOCK_SHARED); + error = filemap_fault(vma, vmf); + xfs_iunlock(ip, XFS_MMAPLOCK_SHARED); + + return error; +} + const struct file_operations xfs_file_operations = { .llseek = xfs_file_llseek, .read = new_sync_read, @@ -1411,7 +1437,7 @@ const struct file_operations xfs_dir_file_operations = { }; static const struct vm_operations_struct xfs_file_vm_ops = { - .fault = filemap_fault, + .fault = xfs_filemap_fault, .map_pages = filemap_map_pages, .page_mkwrite = xfs_vm_page_mkwrite, }; diff --git a/fs/xfs/xfs_trace.h b/fs/xfs/xfs_trace.h index 51372e34d988..c496153b976b 100644 --- a/fs/xfs/xfs_trace.h +++ b/fs/xfs/xfs_trace.h @@ -685,6 +685,8 @@ DEFINE_INODE_EVENT(xfs_inode_set_eofblocks_tag); DEFINE_INODE_EVENT(xfs_inode_clear_eofblocks_tag); DEFINE_INODE_EVENT(xfs_inode_free_eofblocks_invalid); +DEFINE_INODE_EVENT(xfs_filemap_fault); + DECLARE_EVENT_CLASS(xfs_iref_class, TP_PROTO(struct xfs_inode *ip, unsigned long caller_ip), TP_ARGS(ip, caller_ip), |