Again, just a change in the arguments and some function renaming here.
In later patches, we'll change this code to deal with page arrays.
In this patch, we add a new smb_send_rqst wrapper and have smb_sendv
call that. Then we move most of the existing smb_sendv code into a new
function -- smb_send_kvec. This seems a little redundant, but later
we'll flesh this out to deal with arrays of pages.
Reviewed-by: Pavel Shilovsky <pshilovsky@xxxxxxxxx>
Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxx>
---
fs/cifs/transport.c | 135 ++++++++++++++++++++++++++++++++++------------------
1 file changed, 90 insertions(+), 45 deletions(-)
diff --git a/fs/cifs/transport.c b/fs/cifs/transport.c
index bc9ccdd..766307b 100644
--- a/fs/cifs/transport.c
+++ b/fs/cifs/transport.c
@@ -119,18 +119,29 @@ cifs_delete_mid(struct mid_q_entry *mid)
DeleteMidQEntry(mid);
}
+/*
+ * smb_send_kvec - send an array of kvecs to the server
+ * @server: Server to send the data to
+ * @iov: Pointer to array of kvecs
+ * @n_vec: length of kvec array
+ * @sent: amount of data sent on socket is stored here
+ *
+ * Our basic "send data to server" function. Should be called with srv_mutex
+ * held. The caller is responsible for handling the results.
+ */
static int
-smb_sendv(struct TCP_Server_Info *server, struct kvec *iov, int n_vec)
+smb_send_kvec(struct TCP_Server_Info *server, struct kvec *iov, size_t n_vec,
+ size_t *sent)
{
int rc = 0;
int i = 0;
struct msghdr smb_msg;
- unsigned int len = iov[0].iov_len;
- unsigned int total_len;
- int first_vec = 0;
- unsigned int smb_buf_length = get_rfc1002_length(iov[0].iov_base);
+ unsigned int remaining;
+ size_t first_vec = 0;
struct socket *ssocket = server->ssocket;
+ *sent = 0;
+
if (ssocket == NULL)
return -ENOTSOCK; /* BB eventually add reconnect code here */
@@ -143,56 +154,60 @@ smb_sendv(struct TCP_Server_Info *server, struct kvec *iov, int n_vec)
else
smb_msg.msg_flags = MSG_NOSIGNAL;
- total_len = 0;
+ remaining = 0;
for (i = 0; i < n_vec; i++)
- total_len += iov[i].iov_len;
-
- cFYI(1, "Sending smb: total_len %d", total_len);
- dump_smb(iov[0].iov_base, len);
+ remaining += iov[i].iov_len;
i = 0;
- while (total_len) {
+ while (remaining) {
+ /*
+ * If blocking send, we try 3 times, since each can block
+ * for 5 seconds. For nonblocking we have to try more
+ * but wait increasing amounts of time allowing time for
+ * socket to clear. The overall time we wait in either
+ * case to send on the socket is about 15 seconds.
+ * Similarly we wait for 15 seconds for a response from
+ * the server in SendReceive[2] for the server to send
+ * a response back for most types of requests (except
+ * SMB Write past end of file which can be slow, and
+ * blocking lock operations). NFS waits slightly longer
+ * than CIFS, but this can make it take longer for
+ * nonresponsive servers to be detected and 15 seconds
+ * is more than enough time for modern networks to
+ * send a packet. In most cases if we fail to send
+ * after the retries we will kill the socket and
+ * reconnect which may clear the network problem.
+ */
rc = kernel_sendmsg(ssocket, &smb_msg, &iov[first_vec],
- n_vec - first_vec, total_len);
- if ((rc == -ENOSPC) || (rc == -EAGAIN)) {
+ n_vec - first_vec, remaining);
+ if (rc == -ENOSPC || rc == -EAGAIN) {
i++;
- /*
- * If blocking send we try 3 times, since each can block
- * for 5 seconds. For nonblocking we have to try more
- * but wait increasing amounts of time allowing time for
- * socket to clear. The overall time we wait in either
- * case to send on the socket is about 15 seconds.
- * Similarly we wait for 15 seconds for a response from
- * the server in SendReceive[2] for the server to send
- * a response back for most types of requests (except
- * SMB Write past end of file which can be slow, and
- * blocking lock operations). NFS waits slightly longer
- * than CIFS, but this can make it take longer for
- * nonresponsive servers to be detected and 15 seconds
- * is more than enough time for modern networks to
- * send a packet. In most cases if we fail to send
- * after the retries we will kill the socket and
- * reconnect which may clear the network problem.
- */
- if ((i >= 14) || (!server->noblocksnd && (i > 2))) {
- cERROR(1, "sends on sock %p stuck for 15 seconds",
- ssocket);
+ if (i >= 14 || (!server->noblocksnd && (i > 2))) {
+ cERROR(1, "sends on sock %p stuck for 15 "
+ "seconds", ssocket);
rc = -EAGAIN;
break;
}
msleep(1 << i);
continue;
}
+
if (rc < 0)
break;
- if (rc == total_len) {
- total_len = 0;
+ /* send was at least partially successful */
+ *sent += rc;
+
+ if (rc == remaining) {
+ remaining = 0;
break;
- } else if (rc > total_len) {
- cERROR(1, "sent %d requested %d", rc, total_len);
+ }
+
+ if (rc > remaining) {
+ cERROR(1, "sent %d requested %d", rc, remaining);
break;
}
+
if (rc == 0) {
/* should never happen, letting socket clear before
retrying is our only obvious option here */
@@ -200,7 +215,9 @@ smb_sendv(struct TCP_Server_Info *server, struct kvec *iov, int n_vec)
msleep(500);
continue;
}
- total_len -= rc;
+
+ remaining -= rc;
+
/* the line below resets i */
for (i = first_vec; i < n_vec; i++) {
if (iov[i].iov_len) {
@@ -215,16 +232,35 @@ smb_sendv(struct TCP_Server_Info *server, struct kvec *iov, int n_vec)
}
}
}
+
i = 0; /* in case we get ENOSPC on the next send */
+ rc = 0;
}
+ return rc;
+}
+
+static int
+smb_send_rqst(struct TCP_Server_Info *server, struct smb_rqst *rqst)
+{
+ int rc;
+ struct kvec *iov = rqst->rq_iov;
+ int n_vec = rqst->rq_nvec;
+ unsigned int smb_buf_length = get_rfc1002_length(iov[0].iov_base);
+ size_t total_len;
+
+ cFYI(1, "Sending smb: smb_len=%u", smb_buf_length);
+ dump_smb(iov[0].iov_base, iov[0].iov_len);
+
+ rc = smb_send_kvec(server, iov, n_vec, &total_len);
if ((total_len > 0) && (total_len != smb_buf_length + 4)) {
- cFYI(1, "partial send (%d remaining), terminating session",
- total_len);
- /* If we have only sent part of an SMB then the next SMB
- could be taken as the remainder of this one. We need
- to kill the socket so the server throws away the partial
- SMB */
+ cFYI(1, "partial send (wanted=%u sent=%zu): terminating "
+ "session", smb_buf_length + 4, total_len);
+ /*
+ * If we have only sent part of an SMB then the next SMB could
+ * be taken as the remainder of this one. We need to kill the
+ * socket so the server throws away the partial SMB
+ */
server->tcpStatus = CifsNeedReconnect;
}
@@ -236,6 +272,15 @@ smb_sendv(struct TCP_Server_Info *server, struct kvec *iov, int n_vec)
return rc;
}
+static int
+smb_sendv(struct TCP_Server_Info *server, struct kvec *iov, int n_vec)
+{
+ struct smb_rqst rqst = { .rq_iov = iov,
+ .rq_nvec = n_vec };
+
+ return smb_send_rqst(server, &rqst);
+}
+
int
smb_send(struct TCP_Server_Info *server, struct smb_hdr *smb_buffer,
unsigned int smb_buf_length)
--
1.7.11.2
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