[Cluster-devel] [PATCH 1/3] gfs2: Use inode_newsize_ok and get_write_access in fallocate

[Steven Whitehouse]

Hi,

All three patches now in the -nmw tree. Thanks,

Steve.

On 12/11/14 17:24, Andrew Price wrote:
> gfs2_fallocate wasn't checking inode_newsize_ok nor get_write_access.
> Split out the context setup and inode locking pieces into a separate
> function to make it more clear and add these missing calls.
>
> inode_newsize_ok is called conditional on FALLOC_FL_KEEP_SIZE as there
> is no need to enforce a file size limit if it isn't going to change.
>
> Signed-off-by: Andrew Price <anprice at redhat.com>
> ---
>   fs/gfs2/file.c | 66 ++++++++++++++++++++++++++++++++++++++--------------------
>   1 file changed, 44 insertions(+), 22 deletions(-)
>
> diff --git a/fs/gfs2/file.c b/fs/gfs2/file.c
> index 80dd44d..08ee6ce 100644
> --- a/fs/gfs2/file.c
> +++ b/fs/gfs2/file.c
> @@ -796,8 +796,7 @@ static void calc_max_reserv(struct gfs2_inode *ip, loff_t max, loff_t *len,
>   	}
>   }
>   
> -static long gfs2_fallocate(struct file *file, int mode, loff_t offset,
> -			   loff_t len)
> +static long __gfs2_fallocate(struct file *file, int mode, loff_t offset, loff_t len)
>   {
>   	struct inode *inode = file_inode(file);
>   	struct gfs2_sbd *sdp = GFS2_SB(inode);
> @@ -811,14 +810,9 @@ static long gfs2_fallocate(struct file *file, int mode, loff_t offset,
>   	loff_t bsize_mask = ~((loff_t)sdp->sd_sb.sb_bsize - 1);
>   	loff_t next = (offset + len - 1) >> sdp->sd_sb.sb_bsize_shift;
>   	loff_t max_chunk_size = UINT_MAX & bsize_mask;
> -	struct gfs2_holder gh;
>   
>   	next = (next + 1) << sdp->sd_sb.sb_bsize_shift;
>   
> -	/* We only support the FALLOC_FL_KEEP_SIZE mode */
> -	if (mode & ~FALLOC_FL_KEEP_SIZE)
> -		return -EOPNOTSUPP;
> -
>   	offset &= bsize_mask;
>   
>   	len = next - offset;
> @@ -829,17 +823,6 @@ static long gfs2_fallocate(struct file *file, int mode, loff_t offset,
>   	if (bytes == 0)
>   		bytes = sdp->sd_sb.sb_bsize;
>   
> -	error = gfs2_rs_alloc(ip);
> -	if (error)
> -		return error;
> -
> -	mutex_lock(&inode->i_mutex);
> -
> -	gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
> -	error = gfs2_glock_nq(&gh);
> -	if (unlikely(error))
> -		goto out_uninit;
> -
>   	gfs2_size_hint(file, offset, len);
>   
>   	while (len > 0) {
> @@ -852,8 +835,7 @@ static long gfs2_fallocate(struct file *file, int mode, loff_t offset,
>   		}
>   		error = gfs2_quota_lock_check(ip);
>   		if (error)
> -			goto out_unlock;
> -
> +			return error;
>   retry:
>   		gfs2_write_calc_reserv(ip, bytes, &data_blocks, &ind_blocks);
>   
> @@ -897,18 +879,58 @@ retry:
>   
>   	if (error == 0)
>   		error = generic_write_sync(file, pos, count);
> -	goto out_unlock;
> +	return error;
>   
>   out_trans_fail:
>   	gfs2_inplace_release(ip);
>   out_qunlock:
>   	gfs2_quota_unlock(ip);
> +	return error;
> +}
> +
> +static long gfs2_fallocate(struct file *file, int mode, loff_t offset, loff_t len)
> +{
> +	struct inode *inode = file_inode(file);
> +	struct gfs2_inode *ip = GFS2_I(inode);
> +	struct gfs2_holder gh;
> +	int ret;
> +
> +	if (mode & ~FALLOC_FL_KEEP_SIZE)
> +		return -EOPNOTSUPP;
> +
> +	mutex_lock(&inode->i_mutex);
> +
> +	gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
> +	ret = gfs2_glock_nq(&gh);
> +	if (ret)
> +		goto out_uninit;
> +
> +	if (!(mode & FALLOC_FL_KEEP_SIZE) &&
> +	    (offset + len) > inode->i_size) {
> +		ret = inode_newsize_ok(inode, offset + len);
> +		if (ret)
> +			goto out_unlock;
> +	}
> +
> +	ret = get_write_access(inode);
> +	if (ret)
> +		goto out_unlock;
> +
> +	ret = gfs2_rs_alloc(ip);
> +	if (ret)
> +		goto out_putw;
> +
> +	ret = __gfs2_fallocate(file, mode, offset, len);
> +	if (ret)
> +		gfs2_rs_deltree(ip->i_res);
> +out_putw:
> +	put_write_access(inode);
>   out_unlock:
>   	gfs2_glock_dq(&gh);
>   out_uninit:
>   	gfs2_holder_uninit(&gh);
>   	mutex_unlock(&inode->i_mutex);
> -	return error;
> +	return ret;
>   }
>   
>   #ifdef CONFIG_GFS2_FS_LOCKING_DLM