diff options
| -rw-r--r-- | fs/cifs/transport.c | 135 |
1 files changed, 90 insertions, 45 deletions
diff --git a/fs/cifs/transport.c b/fs/cifs/transport.c index bc9ccddad937..766307b725bd 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) |