CIFS: SMBD: Read correct returned data length for RDMA write (SMB read) I/O
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@microsoft.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c
index c8fa4c4..e3393ff 100644
--- a/fs/cifs/smb2ops.c
+++ b/fs/cifs/smb2ops.c
@@ -957,9 +957,13 @@ smb2_read_data_offset(char *buf)
}
static unsigned int
-smb2_read_data_length(char *buf)
+smb2_read_data_length(char *buf, bool in_remaining)
{
struct smb2_read_rsp *rsp = (struct smb2_read_rsp *)buf;
+
+ if (in_remaining)
+ return le32_to_cpu(rsp->DataRemaining);
+
return le32_to_cpu(rsp->DataLength);
}
@@ -2421,6 +2425,7 @@ handle_read_data(struct TCP_Server_Info *server, struct mid_q_entry *mid,
struct iov_iter iter;
struct kvec iov;
int length;
+ bool use_rdma_mr = false;
if (shdr->Command != SMB2_READ) {
cifs_dbg(VFS, "only big read responses are supported\n");
@@ -2447,7 +2452,10 @@ handle_read_data(struct TCP_Server_Info *server, struct mid_q_entry *mid,
}
data_offset = server->ops->read_data_offset(buf) + 4;
- data_len = server->ops->read_data_length(buf);
+#ifdef CONFIG_CIFS_SMB_DIRECT
+ use_rdma_mr = rdata->mr;
+#endif
+ data_len = server->ops->read_data_length(buf, use_rdma_mr);
if (data_offset < server->vals->read_rsp_size) {
/*