2017-10-18 16:09 GMT-07:00 Long Li <longli@xxxxxxxxxxxxxxxxxxxxxx>:
> From: Long Li <longli@xxxxxxxxxxxxx>
>
> This patch is for preparing upper layer doing SMB read via RDMA write.
>
> When RDMA write is used for SMB read, the returned data length is in
> DataRemaining in the response packet. Reading it properly by adding a
> parameter to specifiy where the returned data length is.
>
> Add the defition for memory registration to wdata and return the correct
> length based on if RDMA write is used.
>
> Signed-off-by: Long Li <longli@xxxxxxxxxxxxx>
> ---
> fs/cifs/cifsglob.h | 13 +++++++++++--
> fs/cifs/cifssmb.c | 7 ++++++-
> fs/cifs/smb1ops.c | 6 +++++-
> fs/cifs/smb2ops.c | 12 ++++++++++--
> 4 files changed, 32 insertions(+), 6 deletions(-)
>
> diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
> index 2ae7d02..ddf83d8 100644
> --- a/fs/cifs/cifsglob.h
> +++ b/fs/cifs/cifsglob.h
> @@ -228,8 +228,14 @@ struct smb_version_operations {
> __u64 (*get_next_mid)(struct TCP_Server_Info *);
> /* data offset from read response message */
> unsigned int (*read_data_offset)(char *);
> - /* data length from read response message */
> - unsigned int (*read_data_length)(char *);
> + /*
> + * Data length from read response message
> + * When in_remaining is true, the returned data length is in
> + * message field DataRemaining for out-of-band data read (e.g through
> + * Memory Registration RDMA write in SMBD).
> + * Otherwise, the returned data length is in message field DataLength.
> + */
> + unsigned int (*read_data_length)(char *, bool in_remaining);
> /* map smb to linux error */
> int (*map_error)(char *, bool);
> /* find mid corresponding to the response message */
> @@ -1148,6 +1154,9 @@ struct cifs_readdata {
> struct cifs_readdata *rdata,
> struct iov_iter *iter);
> struct kvec iov[2];
> +#ifdef CONFIG_CIFS_SMB_DIRECT
> + struct smbd_mr *mr;
> +#endif
> unsigned int pagesz;
> unsigned int tailsz;
> unsigned int credits;
> diff --git a/fs/cifs/cifssmb.c b/fs/cifs/cifssmb.c
> index 08ff56a..a343db4 100644
> --- a/fs/cifs/cifssmb.c
> +++ b/fs/cifs/cifssmb.c
> @@ -1533,8 +1533,13 @@ cifs_readv_receive(struct TCP_Server_Info *server, struct mid_q_entry *mid)
> rdata->iov[0].iov_base, server->total_read);
>
> /* how much data is in the response? */
> - data_len = server->ops->read_data_length(buf);
> +#ifdef CONFIG_CIFS_SMB_DIRECT
> + data_len = server->ops->read_data_length(buf, rdata->mr);
> + if (!rdata->mr && (data_offset + data_len > buflen)) {
> +#else
> + data_len = server->ops->read_data_length(buf, false);
> if (data_offset + data_len > buflen) {
> +#endif
> /* data_len is corrupt -- discard frame */
> rdata->result = -EIO;
> return cifs_readv_discard(server, mid);
> diff --git a/fs/cifs/smb1ops.c b/fs/cifs/smb1ops.c
> index a723df3..b718bb8 100644
> --- a/fs/cifs/smb1ops.c
> +++ b/fs/cifs/smb1ops.c
> @@ -87,9 +87,13 @@ cifs_read_data_offset(char *buf)
> }
>
> static unsigned int
> -cifs_read_data_length(char *buf)
> +cifs_read_data_length(char *buf, bool in_remaining)
> {
> READ_RSP *rsp = (READ_RSP *)buf;
> + if (in_remaining) {
> + cifs_dbg(VFS, "Invalid SMB1 calling path, check code\n");
I would suggest to do WARN_ON(1) instead.
> + return 0;
> + }
> return (le16_to_cpu(rsp->DataLengthHigh) << 16) +
> le16_to_cpu(rsp->DataLength);
> }
--
Best regards,
Pavel Shilovsky
--
To unsubscribe from this list: send the line "unsubscribe linux-rdma" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
