[PATCH] vfs_glusterfs: Add fallocate support for vfs_glusterfs

[David Disseldorp]

Hi Sachin,

A couple of comments inline...

On Tue, 09 Jan 2018 13:02:13 +0530, Sachin Prabhu via samba-technical wrote:

> From 05f47588b2641242d219564e6eb8468f9484a3d4 Mon Sep 17 00:00:00 2001
> From: Sachin Prabhu <sprabhu at redhat.com>
> Date: Tue, 14 Nov 2017 15:51:44 +0530
> Subject: [PATCH] vfs_glusterfs: Add fallocate support for vfs_glusterfs
> 
> Adds fallocate support to the vfs glusterfs plugin.
> 
> RHBZ: 1478875
> 
> Signed-off-by: Sachin Prabhu <sprabhu at redhat.com>
> ---
>  source3/modules/vfs_glusterfs.c | 26 ++++++++++++++++++++++----
>  1 file changed, 22 insertions(+), 4 deletions(-)
> 
> diff --git a/source3/modules/vfs_glusterfs.c b/source3/modules/vfs_glusterfs.c
> index 953c46af4cd..c0ea722c1df 100644
> --- a/source3/modules/vfs_glusterfs.c
> +++ b/source3/modules/vfs_glusterfs.c
> @@ -462,7 +462,8 @@ static int vfs_gluster_statvfs(struct vfs_handle_struct *handle,
>  static uint32_t vfs_gluster_fs_capabilities(struct vfs_handle_struct *handle,
>  					    enum timestamp_set_resolution *p_ts_res)
>  {
> -	uint32_t caps = FILE_CASE_SENSITIVE_SEARCH | FILE_CASE_PRESERVED_NAMES;
> +	uint32_t caps = FILE_CASE_SENSITIVE_SEARCH | FILE_CASE_PRESERVED_NAMES
> +			| FILE_SUPPORTS_SPARSE_FILES;

Does glusterfs support SEEK_DATA / SEEK_HOLE? Keep in mind that sparse
aware clients may issue Query Allocated Ranges requests, which can be
mapped by the SMB2 server into VFS lseek(SEEK_DATA / SEEK_HOLE) calls.

>  #ifdef STAT_HAVE_NSEC
>  	*p_ts_res = TIMESTAMP_SET_NT_OR_BETTER;
> @@ -1148,9 +1149,26 @@ static int vfs_gluster_fallocate(struct vfs_handle_struct *handle,
>  				 uint32_t mode,
>  				 off_t offset, off_t len)
>  {
> -	/* TODO: add support using glfs_fallocate() and glfs_zerofill() */
> -	errno = ENOTSUP;
> -	return -1;
> +	int keep_size, punch_hole;
> +
> +	keep_size = mode & VFS_FALLOCATE_FL_KEEP_SIZE;
> +	punch_hole = mode & VFS_FALLOCATE_FL_PUNCH_HOLE;
> +
> +	mode &= ~(VFS_FALLOCATE_FL_KEEP_SIZE|VFS_FALLOCATE_FL_PUNCH_HOLE);
> +	if (mode) {
> +		errno = ENOTSUP;
> +		return -1;
> +	}
> +
> +	if (punch_hole) {
> +		return glfs_discard(*(glfs_fd_t **)
> +				    VFS_FETCH_FSP_EXTENSION(handle, fsp),
> +				    offset, len);

I assume glfs_discard() will never change the file size here, i.e. it
matches fallocate(mode = VFS_FALLOCATE_FL_PUNCH_HOLE
			| VFS_FALLOCATE_FL_KEEP_SIZE) behaviour?
> +	}
> +
> +	return glfs_fallocate(*(glfs_fd_t **)
> +			      VFS_FETCH_FSP_EXTENSION(handle, fsp),
> +			      keep_size, offset, len);
>  }
>  
>  static struct smb_filename *vfs_gluster_realpath(struct vfs_handle_struct *handle,

Cheers, David