Re: [PATCH v5 6/7] ext4: call dax_pfn_mkwrite() for DAX fsync/msync

Jan Kara
2015-12-21T17:32:27Z

On Fri 18-12-15 22:22:19, Ross Zwisler wrote:
> To properly support the new DAX fsync/msync infrastructure filesystems
> need to call dax_pfn_mkwrite() so that DAX can track when user pages are
> dirtied.

The patch looks good to me. You can add:

Reviewed-by: Jan Kara <jack@suse.cz>

Honza

>
> Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
> ---
> fs/ext4/file.c | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/fs/ext4/file.c b/fs/ext4/file.c
> index 749b222..8c8965c 100644
> --- a/fs/ext4/file.c
> +++ b/fs/ext4/file.c
> @@ -291,8 +291,8 @@ static int ext4_dax_pfn_mkwrite(struct vm_area_struct *vma,
> {
> struct inode *inode = file_inode(vma->vm_file);
> struct super_block *sb = inode->i_sb;
> - int ret = VM_FAULT_NOPAGE;
> loff_t size;
> + int ret;
>
> sb_start_pagefault(sb);
> file_update_time(vma->vm_file);
> @@ -300,6 +300,8 @@ static int ext4_dax_pfn_mkwrite(struct vm_area_struct *vma,
> size = (i_size_read(inode) + PAGE_SIZE - 1) >> PAGE_SHIFT;
> if (vmf->pgoff >= size)
> ret = VM_FAULT_SIGBUS;
> + else
> + ret = dax_pfn_mkwrite(vma, vmf);
> up_read(&EXT4_I(inode)->i_mmap_sem);
> sb_end_pagefault(sb);
>
> --
> 2.5.0
>
>
--
Jan Kara <jack@suse.com>
SUSE Labs, CR