Re: [PATCH 3/3] nfsd: Add DEALLOCATE support

["J. Bruce Fields" <bfields@fieldses.org>]

On Tue, Sep 09, 2014 at 10:49:42AM -0400, Anna.Schumaker@netapp.com wrote:
> From: Anna Schumaker <Anna.Schumaker@Netapp.com>
> 
> The DEALLOCATE operation is used to punch holes in a file.
> 
> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
> ---
>  fs/nfsd/nfs4proc.c | 31 ++++++++++++++++++++++++++++++-
>  fs/nfsd/nfs4xdr.c  | 19 ++++++++++++++++++-
>  fs/nfsd/vfs.c      |  8 ++++++--
>  fs/nfsd/vfs.h      |  2 +-
>  fs/nfsd/xdr4.h     |  8 ++++++++
>  5 files changed, 63 insertions(+), 5 deletions(-)
> 
> diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c
> index f9d8fac..ac18be6 100644
> --- a/fs/nfsd/nfs4proc.c
> +++ b/fs/nfsd/nfs4proc.c
> @@ -1028,7 +1028,7 @@ nfsd4_allocate(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
>  		return status;
>  	}
>  
> -	status = nfsd4_vfs_fallocate(&cstate->current_fh, file,
> +	status = nfsd4_vfs_fallocate(&cstate->current_fh, file, false,
>  				     allocate->alloc_offset,
>  				     allocate->alloc_length);
>  	fput(file);
> @@ -1036,6 +1036,28 @@ nfsd4_allocate(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
>  }
>  
>  static __be32
> +nfsd4_deallocate(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
> +		struct nfsd4_deallocate *deallocate)
> +{
> +	__be32 status = nfserr_notsupp;
> +	struct file *file;
> +
> +	status = nfs4_preprocess_stateid_op(SVC_NET(rqstp), cstate,
> +					    &deallocate->dealloc_stateid,
> +					    WR_STATE, &file);
> +	if (status != nfs_ok) {
> +		dprintk("NFSD: nfsd4_deallocate: couldn't process stateid!\n");
> +		return status;
> +	}
> +
> +	status = nfsd4_vfs_fallocate(&cstate->current_fh, file, true,
> +				     deallocate->dealloc_offset,
> +				     deallocate->dealloc_length);

Same comment as in allocate case.

--b.

> +	fput(file);
> +	return status;
> +}
> +
> +static __be32
>  nfsd4_seek(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
>  		struct nfsd4_seek *seek)
>  {
> @@ -1949,6 +1971,13 @@ static struct nfsd4_operation nfsd4_ops[] = {
>  		.op_rsize_bop = (nfsd4op_rsize)nfsd4_write_rsize,
>  		.op_get_currentstateid = (stateid_getter)nfsd4_get_writestateid,
>  	},
> +	[OP_DEALLOCATE] = {
> +		.op_func = (nfsd4op_func)nfsd4_deallocate,
> +		.op_flags = OP_MODIFIES_SOMETHING | OP_CACHEME,
> +		.op_name = "OP_DEALLOCATE",
> +		.op_rsize_bop = (nfsd4op_rsize)nfsd4_write_rsize,
> +		.op_get_currentstateid = (stateid_getter)nfsd4_get_writestateid,
> +	},
>  	[OP_SEEK] = {
>  		.op_func = (nfsd4op_func)nfsd4_seek,
>  		.op_name = "OP_SEEK",
> diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
> index a55aa3b..e1059ce 100644
> --- a/fs/nfsd/nfs4xdr.c
> +++ b/fs/nfsd/nfs4xdr.c
> @@ -1538,6 +1538,23 @@ nfsd4_decode_allocate(struct nfsd4_compoundargs *argp,
>  }
>  
>  static __be32
> +nfsd4_decode_deallocate(struct nfsd4_compoundargs *argp,
> +		      struct nfsd4_deallocate *deallocate)
> +{
> +	DECODE_HEAD;
> +
> +	status = nfsd4_decode_stateid(argp, &deallocate->dealloc_stateid);
> +	if (status)
> +		return status;
> +
> +	READ_BUF(16);
> +	p = xdr_decode_hyper(p, &deallocate->dealloc_offset);
> +	xdr_decode_hyper(p, &deallocate->dealloc_length);
> +
> +	DECODE_TAIL;
> +}
> +
> +static __be32
>  nfsd4_decode_seek(struct nfsd4_compoundargs *argp, struct nfsd4_seek *seek)
>  {
>  	DECODE_HEAD;
> @@ -1631,7 +1648,7 @@ static nfsd4_dec nfsd4_dec_ops[] = {
>  	[OP_ALLOCATE]		= (nfsd4_dec)nfsd4_decode_allocate,
>  	[OP_COPY]		= (nfsd4_dec)nfsd4_decode_notsupp,
>  	[OP_COPY_NOTIFY]	= (nfsd4_dec)nfsd4_decode_notsupp,
> -	[OP_DEALLOCATE]		= (nfsd4_dec)nfsd4_decode_notsupp,
> +	[OP_DEALLOCATE]		= (nfsd4_dec)nfsd4_decode_deallocate,
>  	[OP_IO_ADVISE]		= (nfsd4_dec)nfsd4_decode_notsupp,
>  	[OP_LAYOUTERROR]	= (nfsd4_dec)nfsd4_decode_notsupp,
>  	[OP_LAYOUTSTATS]	= (nfsd4_dec)nfsd4_decode_notsupp,
> diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
> index 4b1dba0..2bf5263 100644
> --- a/fs/nfsd/vfs.c
> +++ b/fs/nfsd/vfs.c
> @@ -525,9 +525,13 @@ __be32 nfsd4_set_nfs4_label(struct svc_rqst *rqstp, struct svc_fh *fhp,
>  #endif
>  
>  __be32 nfsd4_vfs_fallocate(struct svc_fh *fhp, struct file *file,
> -			   loff_t offset, loff_t len)
> +			   bool punch, loff_t offset, loff_t len)
>  {
> -	int error = vfs_fallocate(file, 0, offset, len);
> +	int error, mode = 0;
> +	if (punch)
> +		mode = FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE;
> +
> +	error = vfs_fallocate(file, mode, offset, len);
>  	if (error < 0)
>  		return nfserrno(error);
>  	return nfserrno(commit_metadata(fhp));
> diff --git a/fs/nfsd/vfs.h b/fs/nfsd/vfs.h
> index 9d88c88..9301e8e 100644
> --- a/fs/nfsd/vfs.h
> +++ b/fs/nfsd/vfs.h
> @@ -54,7 +54,7 @@ int nfsd_mountpoint(struct dentry *, struct svc_export *);
>  #ifdef CONFIG_NFSD_V4
>  __be32          nfsd4_set_nfs4_label(struct svc_rqst *, struct svc_fh *,
>  		    struct xdr_netobj *);
> -__be32		nfsd4_vfs_fallocate(struct svc_fh *, struct file *, loff_t, loff_t);
> +__be32		nfsd4_vfs_fallocate(struct svc_fh *, struct file *, bool, loff_t, loff_t);
>  #endif /* CONFIG_NFSD_V4 */
>  __be32		nfsd_create(struct svc_rqst *, struct svc_fh *,
>  				char *name, int len, struct iattr *attrs,
> diff --git a/fs/nfsd/xdr4.h b/fs/nfsd/xdr4.h
> index 4a01fa8..2866921 100644
> --- a/fs/nfsd/xdr4.h
> +++ b/fs/nfsd/xdr4.h
> @@ -435,6 +435,13 @@ struct nfsd4_allocate {
>  	u64		alloc_length;
>  };
>  
> +struct nfsd4_deallocate {
> +	/* request */
> +	stateid_t	dealloc_stateid;
> +	loff_t		dealloc_offset;
> +	u64		dealloc_length;
> +};
> +
>  struct nfsd4_seek {
>  	/* request */
>  	stateid_t	seek_stateid;
> @@ -494,6 +501,7 @@ struct nfsd4_op {
>  
>  		/* NFSv4.2 */
>  		struct nfsd4_allocate		allocate;
> +		struct nfsd4_deallocate		deallocate;
>  		struct nfsd4_seek		seek;
>  	} u;
>  	struct nfs4_replay *			replay;
> -- 
> 2.1.0
>