1 files changed, 202 insertions, 88 deletions

diff --git a/fs/cifs/transport.c b/fs/cifs/transport.c
index 83867ef348df..2126ab185045 100644
--- a/fs/cifs/transport.c
+++ b/fs/cifs/transport.c
@@ -27,6 +27,8 @@
 #include <linux/net.h>
 #include <linux/delay.h>
 #include <linux/freezer.h>
+#include <linux/tcp.h>
+#include <linux/highmem.h>
 #include <asm/uaccess.h>
 #include <asm/processor.h>
 #include <linux/mempool.h>
@@ -109,8 +111,8 @@ DeleteMidQEntry(struct mid_q_entry *midEntry)
         mempool_free(midEntry, cifs_mid_poolp);
 }
 
-static void
-delete_mid(struct mid_q_entry *mid)
+void
+cifs_delete_mid(struct mid_q_entry *mid)
 {
         spin_lock(&GlobalMid_Lock);
         list_del(&mid->qhead);
@@ -119,18 +121,29 @@ 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 +156,60 @@ 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 +217,9 @@ 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 +234,97 @@ 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;
+}
+
+/**
+ * rqst_page_to_kvec - Turn a slot in the smb_rqst page array into a kvec
+ * @rqst: pointer to smb_rqst
+ * @idx: index into the array of the page
+ * @iov: pointer to struct kvec that will hold the result
+ *
+ * Helper function to convert a slot in the rqst->rq_pages array into a kvec.
+ * The page will be kmapped and the address placed into iov_base. The length
+ * will then be adjusted according to the ptailoff.
+ */
+void
+cifs_rqst_page_to_kvec(struct smb_rqst *rqst, unsigned int idx,
+                        struct kvec *iov)
+{
+        /*
+         * FIXME: We could avoid this kmap altogether if we used
+         * kernel_sendpage instead of kernel_sendmsg. That will only
+         * work if signing is disabled though as sendpage inlines the
+         * page directly into the fraglist. If userspace modifies the
+         * page after we calculate the signature, then the server will
+         * reject it and may break the connection. kernel_sendmsg does
+         * an extra copy of the data and avoids that issue.
+         */
+        iov->iov_base = kmap(rqst->rq_pages[idx]);
+
+        /* if last page, don't send beyond this offset into page */
+        if (idx == (rqst->rq_npages - 1))
+                iov->iov_len = rqst->rq_tailsz;
+        else
+                iov->iov_len = rqst->rq_pagesz;
+}
+
+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);
+        unsigned int i;
+        size_t total_len = 0, sent;
+        struct socket *ssocket = server->ssocket;
+        int val = 1;
+
+        cFYI(1, "Sending smb: smb_len=%u", smb_buf_length);
+        dump_smb(iov[0].iov_base, iov[0].iov_len);
+
+        /* cork the socket */
+        kernel_setsockopt(ssocket, SOL_TCP, TCP_CORK,
+                                (char *)&val, sizeof(val));
+
+        rc = smb_send_kvec(server, iov, n_vec, &sent);
+        if (rc < 0)
+                goto uncork;
+
+        total_len += sent;
+
+        /* now walk the page array and send each page in it */
+        for (i = 0; i < rqst->rq_npages; i++) {
+                struct kvec p_iov;
+
+                cifs_rqst_page_to_kvec(rqst, i, &p_iov);
+                rc = smb_send_kvec(server, &p_iov, 1, &sent);
+                kunmap(rqst->rq_pages[i]);
+                if (rc < 0)
+                        break;
+
+                total_len += sent;
+        }
+
+uncork:
+        /* uncork it */
+        val = 0;
+        kernel_setsockopt(ssocket, SOL_TCP, TCP_CORK,
+                                (char *)&val, sizeof(val));
 
         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 +336,15 @@ 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)
@@ -345,12 +454,11 @@ wait_for_response(struct TCP_Server_Info *server, struct mid_q_entry *midQ)
         return 0;
 }
 
-int
-cifs_setup_async_request(struct TCP_Server_Info *server, struct kvec *iov,
-                         unsigned int nvec, struct mid_q_entry **ret_mid)
+struct mid_q_entry *
+cifs_setup_async_request(struct TCP_Server_Info *server, struct smb_rqst *rqst)
 {
         int rc;
-        struct smb_hdr *hdr = (struct smb_hdr *)iov[0].iov_base;
+        struct smb_hdr *hdr = (struct smb_hdr *)rqst->rq_iov[0].iov_base;
         struct mid_q_entry *mid;
 
         /* enable signing if server requires it */
@@ -359,16 +467,15 @@ cifs_setup_async_request(struct TCP_Server_Info *server, struct kvec *iov,
 
         mid = AllocMidQEntry(hdr, server);
         if (mid == NULL)
-                return -ENOMEM;
+                return ERR_PTR(-ENOMEM);
 
-        rc = cifs_sign_smbv(iov, nvec, server, &mid->sequence_number);
+        rc = cifs_sign_rqst(rqst, server, &mid->sequence_number);
         if (rc) {
                 DeleteMidQEntry(mid);
-                return rc;
+                return ERR_PTR(rc);
         }
 
-        *ret_mid = mid;
-        return 0;
+        return mid;
 }
 
 /*
@@ -376,9 +483,9 @@ cifs_setup_async_request(struct TCP_Server_Info *server, struct kvec *iov,
  * the result. Caller is responsible for dealing with timeouts.
  */
 int
-cifs_call_async(struct TCP_Server_Info *server, struct kvec *iov,
-                unsigned int nvec, mid_receive_t *receive,
-                mid_callback_t *callback, void *cbdata, const int flags)
+cifs_call_async(struct TCP_Server_Info *server, struct smb_rqst *rqst,
+                mid_receive_t *receive, mid_callback_t *callback,
+                void *cbdata, const int flags)
 {
         int rc, timeout, optype;
         struct mid_q_entry *mid;
@@ -391,12 +498,12 @@ cifs_call_async(struct TCP_Server_Info *server, struct kvec *iov,
                 return rc;
 
         mutex_lock(&server->srv_mutex);
-        rc = server->ops->setup_async_request(server, iov, nvec, &mid);
-        if (rc) {
+        mid = server->ops->setup_async_request(server, rqst);
+        if (IS_ERR(mid)) {
                 mutex_unlock(&server->srv_mutex);
                 add_credits(server, 1, optype);
                 wake_up(&server->request_q);
-                return rc;
+                return PTR_ERR(mid);
         }
 
         mid->receive = receive;
@@ -411,7 +518,7 @@ cifs_call_async(struct TCP_Server_Info *server, struct kvec *iov,
 
 
         cifs_in_send_inc(server);
-        rc = smb_sendv(server, iov, nvec);
+        rc = smb_send_rqst(server, rqst);
         cifs_in_send_dec(server);
         cifs_save_when_sent(mid);
         mutex_unlock(&server->srv_mutex);
@@ -419,7 +526,7 @@ cifs_call_async(struct TCP_Server_Info *server, struct kvec *iov,
         if (rc == 0)
                 return 0;
 
-        delete_mid(mid);
+        cifs_delete_mid(mid);
         add_credits(server, 1, optype);
         wake_up(&server->request_q);
         return rc;
@@ -503,35 +610,40 @@ cifs_check_receive(struct mid_q_entry *mid, struct TCP_Server_Info *server,
         /* convert the length into a more usable form */
         if (server->sec_mode & (SECMODE_SIGN_REQUIRED | SECMODE_SIGN_ENABLED)) {
                 struct kvec iov;
+                int rc = 0;
+                struct smb_rqst rqst = { .rq_iov = &iov,
+                                         .rq_nvec = 1 };
 
                 iov.iov_base = mid->resp_buf;
                 iov.iov_len = len;
                 /* FIXME: add code to kill session */
-                if (cifs_verify_signature(&iov, 1, server,
-                                          mid->sequence_number + 1) != 0)
-                        cERROR(1, "Unexpected SMB signature");
+                rc = cifs_verify_signature(&rqst, server,
+                                           mid->sequence_number + 1);
+                if (rc)
+                        cERROR(1, "SMB signature verification returned error = "
+                               "%d", rc);
         }
 
         /* BB special case reconnect tid and uid here? */
         return map_smb_to_linux_error(mid->resp_buf, log_error);
 }
 
-int
-cifs_setup_request(struct cifs_ses *ses, struct kvec *iov,
-                   unsigned int nvec, struct mid_q_entry **ret_mid)
+struct mid_q_entry *
+cifs_setup_request(struct cifs_ses *ses, struct smb_rqst *rqst)
 {
         int rc;
-        struct smb_hdr *hdr = (struct smb_hdr *)iov[0].iov_base;
+        struct smb_hdr *hdr = (struct smb_hdr *)rqst->rq_iov[0].iov_base;
         struct mid_q_entry *mid;
 
         rc = allocate_mid(ses, hdr, &mid);
         if (rc)
-                return rc;
-        rc = cifs_sign_smbv(iov, nvec, ses->server, &mid->sequence_number);
-        if (rc)
-                delete_mid(mid);
-        *ret_mid = mid;
-        return rc;
+                return ERR_PTR(rc);
+        rc = cifs_sign_rqst(rqst, ses->server, &mid->sequence_number);
+        if (rc) {
+                cifs_delete_mid(mid);
+                return ERR_PTR(rc);
+        }
+        return mid;
 }
 
 int
@@ -544,6 +656,8 @@ SendReceive2(const unsigned int xid, struct cifs_ses *ses,
         struct mid_q_entry *midQ;
         char *buf = iov[0].iov_base;
         unsigned int credits = 1;
+        struct smb_rqst rqst = { .rq_iov = iov,
+                                 .rq_nvec = n_vec };
 
         timeout = flags & CIFS_TIMEOUT_MASK;
         optype = flags & CIFS_OP_MASK;
@@ -581,13 +695,13 @@ SendReceive2(const unsigned int xid, struct cifs_ses *ses,
 
         mutex_lock(&ses->server->srv_mutex);
 
-        rc = ses->server->ops->setup_request(ses, iov, n_vec, &midQ);
-        if (rc) {
+        midQ = ses->server->ops->setup_request(ses, &rqst);
+        if (IS_ERR(midQ)) {
                 mutex_unlock(&ses->server->srv_mutex);
                 cifs_small_buf_release(buf);
                 /* Update # of requests on wire to server */
                 add_credits(ses->server, 1, optype);
-                return rc;
+                return PTR_ERR(midQ);
         }
 
         midQ->mid_state = MID_REQUEST_SUBMITTED;
@@ -649,11 +763,11 @@ SendReceive2(const unsigned int xid, struct cifs_ses *ses,
         rc = ses->server->ops->check_receive(midQ, ses->server,
                                              flags & CIFS_LOG_ERROR);
 
-        /* mark it so buf will not be freed by delete_mid */
+        /* mark it so buf will not be freed by cifs_delete_mid */
         if ((flags & CIFS_NO_RESP) == 0)
                 midQ->resp_buf = NULL;
 out:
-        delete_mid(midQ);
+        cifs_delete_mid(midQ);
         add_credits(ses->server, credits, optype);
 
         return rc;
@@ -759,7 +873,7 @@ SendReceive(const unsigned int xid, struct cifs_ses *ses,
         memcpy(out_buf, midQ->resp_buf, *pbytes_returned + 4);
         rc = cifs_check_receive(midQ, ses->server, 0);
 out:
-        delete_mid(midQ);
+        cifs_delete_mid(midQ);
         add_credits(ses->server, 1, 0);
 
         return rc;
@@ -843,7 +957,7 @@ SendReceiveBlockingLock(const unsigned int xid, struct cifs_tcon *tcon,
 
         rc = cifs_sign_smb(in_buf, ses->server, &midQ->sequence_number);
         if (rc) {
-                delete_mid(midQ);
+                cifs_delete_mid(midQ);
                 mutex_unlock(&ses->server->srv_mutex);
                 return rc;
         }
@@ -856,7 +970,7 @@ SendReceiveBlockingLock(const unsigned int xid, struct cifs_tcon *tcon,
         mutex_unlock(&ses->server->srv_mutex);
 
         if (rc < 0) {
-                delete_mid(midQ);
+                cifs_delete_mid(midQ);
                 return rc;
         }
 
@@ -877,7 +991,7 @@ SendReceiveBlockingLock(const unsigned int xid, struct cifs_tcon *tcon,
                            blocking lock to return. */
                         rc = send_cancel(ses->server, in_buf, midQ);
                         if (rc) {
-                                delete_mid(midQ);
+                                cifs_delete_mid(midQ);
                                 return rc;
                         }
                 } else {
@@ -889,7 +1003,7 @@ SendReceiveBlockingLock(const unsigned int xid, struct cifs_tcon *tcon,
                         /* If we get -ENOLCK back the lock may have
                            already been removed. Don't exit in this case. */
                         if (rc && rc != -ENOLCK) {
-                                delete_mid(midQ);
+                                cifs_delete_mid(midQ);
                                 return rc;
                         }
                 }
@@ -926,7 +1040,7 @@ SendReceiveBlockingLock(const unsigned int xid, struct cifs_tcon *tcon,
         memcpy(out_buf, midQ->resp_buf, *pbytes_returned + 4);
         rc = cifs_check_receive(midQ, ses->server, 0);
 out:
-        delete_mid(midQ);
+        cifs_delete_mid(midQ);
         if (rstart && rc == -EACCES)
                 return -ERESTARTSYS;
         return rc;