| /* |
| * fs/cifs/transport.c |
| * |
| * Copyright (C) International Business Machines Corp., 2002,2008 |
| * Author(s): Steve French (sfrench@us.ibm.com) |
| * Jeremy Allison (jra@samba.org) 2006. |
| * |
| * This library is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU Lesser General Public License as published |
| * by the Free Software Foundation; either version 2.1 of the License, or |
| * (at your option) any later version. |
| * |
| * This library is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See |
| * the GNU Lesser General Public License for more details. |
| * |
| * You should have received a copy of the GNU Lesser General Public License |
| * along with this library; if not, write to the Free Software |
| * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| */ |
| |
| #include <linux/fs.h> |
| #include <linux/list.h> |
| #include <linux/gfp.h> |
| #include <linux/wait.h> |
| #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> |
| #include "cifspdu.h" |
| #include "cifsglob.h" |
| #include "cifsproto.h" |
| #include "cifs_debug.h" |
| |
| void |
| cifs_wake_up_task(struct mid_q_entry *mid) |
| { |
| wake_up_process(mid->callback_data); |
| } |
| |
| struct mid_q_entry * |
| AllocMidQEntry(const struct smb_hdr *smb_buffer, struct TCP_Server_Info *server) |
| { |
| struct mid_q_entry *temp; |
| |
| if (server == NULL) { |
| cifs_dbg(VFS, "Null TCP session in AllocMidQEntry\n"); |
| return NULL; |
| } |
| |
| temp = mempool_alloc(cifs_mid_poolp, GFP_NOFS); |
| if (temp == NULL) |
| return temp; |
| else { |
| memset(temp, 0, sizeof(struct mid_q_entry)); |
| temp->mid = smb_buffer->Mid; /* always LE */ |
| temp->pid = current->pid; |
| temp->command = cpu_to_le16(smb_buffer->Command); |
| cifs_dbg(FYI, "For smb_command %d\n", smb_buffer->Command); |
| /* do_gettimeofday(&temp->when_sent);*/ /* easier to use jiffies */ |
| /* when mid allocated can be before when sent */ |
| temp->when_alloc = jiffies; |
| temp->server = server; |
| |
| /* |
| * The default is for the mid to be synchronous, so the |
| * default callback just wakes up the current task. |
| */ |
| temp->callback = cifs_wake_up_task; |
| temp->callback_data = current; |
| } |
| |
| atomic_inc(&midCount); |
| temp->mid_state = MID_REQUEST_ALLOCATED; |
| return temp; |
| } |
| |
| void |
| DeleteMidQEntry(struct mid_q_entry *midEntry) |
| { |
| #ifdef CONFIG_CIFS_STATS2 |
| __le16 command = midEntry->server->vals->lock_cmd; |
| unsigned long now; |
| #endif |
| midEntry->mid_state = MID_FREE; |
| atomic_dec(&midCount); |
| if (midEntry->large_buf) |
| cifs_buf_release(midEntry->resp_buf); |
| else |
| cifs_small_buf_release(midEntry->resp_buf); |
| #ifdef CONFIG_CIFS_STATS2 |
| now = jiffies; |
| /* commands taking longer than one second are indications that |
| something is wrong, unless it is quite a slow link or server */ |
| if ((now - midEntry->when_alloc) > HZ) { |
| if ((cifsFYI & CIFS_TIMER) && (midEntry->command != command)) { |
| printk(KERN_DEBUG " CIFS slow rsp: cmd %d mid %llu", |
| midEntry->command, midEntry->mid); |
| printk(" A: 0x%lx S: 0x%lx R: 0x%lx\n", |
| now - midEntry->when_alloc, |
| now - midEntry->when_sent, |
| now - midEntry->when_received); |
| } |
| } |
| #endif |
| mempool_free(midEntry, cifs_mid_poolp); |
| } |
| |
| void |
| cifs_delete_mid(struct mid_q_entry *mid) |
| { |
| spin_lock(&GlobalMid_Lock); |
| list_del(&mid->qhead); |
| spin_unlock(&GlobalMid_Lock); |
| |
| 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_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 remaining; |
| size_t first_vec = 0; |
| struct socket *ssocket = server->ssocket; |
| |
| *sent = 0; |
| |
| smb_msg.msg_name = (struct sockaddr *) &server->dstaddr; |
| smb_msg.msg_namelen = sizeof(struct sockaddr); |
| smb_msg.msg_control = NULL; |
| smb_msg.msg_controllen = 0; |
| if (server->noblocksnd) |
| smb_msg.msg_flags = MSG_DONTWAIT + MSG_NOSIGNAL; |
| else |
| smb_msg.msg_flags = MSG_NOSIGNAL; |
| |
| remaining = 0; |
| for (i = 0; i < n_vec; i++) |
| remaining += iov[i].iov_len; |
| |
| i = 0; |
| 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, remaining); |
| if (rc == -EAGAIN) { |
| i++; |
| if (i >= 14 || (!server->noblocksnd && (i > 2))) { |
| cifs_dbg(VFS, "sends on sock %p stuck for 15 seconds\n", |
| ssocket); |
| rc = -EAGAIN; |
| break; |
| } |
| msleep(1 << i); |
| continue; |
| } |
| |
| if (rc < 0) |
| break; |
| |
| /* send was at least partially successful */ |
| *sent += rc; |
| |
| if (rc == remaining) { |
| remaining = 0; |
| break; |
| } |
| |
| if (rc > remaining) { |
| cifs_dbg(VFS, "sent %d requested %d\n", rc, remaining); |
| break; |
| } |
| |
| if (rc == 0) { |
| /* should never happen, letting socket clear before |
| retrying is our only obvious option here */ |
| cifs_dbg(VFS, "tcp sent no data\n"); |
| msleep(500); |
| continue; |
| } |
| |
| remaining -= rc; |
| |
| /* the line below resets i */ |
| for (i = first_vec; i < n_vec; i++) { |
| if (iov[i].iov_len) { |
| if (rc > iov[i].iov_len) { |
| rc -= iov[i].iov_len; |
| iov[i].iov_len = 0; |
| } else { |
| iov[i].iov_base += rc; |
| iov[i].iov_len -= rc; |
| first_vec = i; |
| break; |
| } |
| } |
| } |
| |
| 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; |
| |
| if (ssocket == NULL) |
| return -ENOTSOCK; |
| |
| cifs_dbg(FYI, "Sending smb: smb_len=%u\n", 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)) { |
| cifs_dbg(FYI, "partial send (wanted=%u sent=%zu): terminating session\n", |
| 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; |
| } |
| |
| if (rc < 0 && rc != -EINTR) |
| cifs_dbg(VFS, "Error %d sending data on socket to server\n", |
| rc); |
| else |
| rc = 0; |
| |
| 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) |
| { |
| struct kvec iov; |
| |
| iov.iov_base = smb_buffer; |
| iov.iov_len = smb_buf_length + 4; |
| |
| return smb_sendv(server, &iov, 1); |
| } |
| |
| static int |
| wait_for_free_credits(struct TCP_Server_Info *server, const int timeout, |
| int *credits) |
| { |
| int rc; |
| |
| spin_lock(&server->req_lock); |
| if (timeout == CIFS_ASYNC_OP) { |
| /* oplock breaks must not be held up */ |
| server->in_flight++; |
| *credits -= 1; |
| spin_unlock(&server->req_lock); |
| return 0; |
| } |
| |
| while (1) { |
| if (*credits <= 0) { |
| spin_unlock(&server->req_lock); |
| cifs_num_waiters_inc(server); |
| rc = wait_event_killable(server->request_q, |
| has_credits(server, credits)); |
| cifs_num_waiters_dec(server); |
| if (rc) |
| return rc; |
| spin_lock(&server->req_lock); |
| } else { |
| if (server->tcpStatus == CifsExiting) { |
| spin_unlock(&server->req_lock); |
| return -ENOENT; |
| } |
| |
| /* |
| * Can not count locking commands against total |
| * as they are allowed to block on server. |
| */ |
| |
| /* update # of requests on the wire to server */ |
| if (timeout != CIFS_BLOCKING_OP) { |
| *credits -= 1; |
| server->in_flight++; |
| } |
| spin_unlock(&server->req_lock); |
| break; |
| } |
| } |
| return 0; |
| } |
| |
| static int |
| wait_for_free_request(struct TCP_Server_Info *server, const int timeout, |
| const int optype) |
| { |
| return wait_for_free_credits(server, timeout, |
| server->ops->get_credits_field(server, optype)); |
| } |
| |
| static int allocate_mid(struct cifs_ses *ses, struct smb_hdr *in_buf, |
| struct mid_q_entry **ppmidQ) |
| { |
| if (ses->server->tcpStatus == CifsExiting) { |
| return -ENOENT; |
| } |
| |
| if (ses->server->tcpStatus == CifsNeedReconnect) { |
| cifs_dbg(FYI, "tcp session dead - return to caller to retry\n"); |
| return -EAGAIN; |
| } |
| |
| if (ses->status != CifsGood) { |
| /* check if SMB session is bad because we are setting it up */ |
| if ((in_buf->Command != SMB_COM_SESSION_SETUP_ANDX) && |
| (in_buf->Command != SMB_COM_NEGOTIATE)) |
| return -EAGAIN; |
| /* else ok - we are setting up session */ |
| } |
| *ppmidQ = AllocMidQEntry(in_buf, ses->server); |
| if (*ppmidQ == NULL) |
| return -ENOMEM; |
| spin_lock(&GlobalMid_Lock); |
| list_add_tail(&(*ppmidQ)->qhead, &ses->server->pending_mid_q); |
| spin_unlock(&GlobalMid_Lock); |
| return 0; |
| } |
| |
| static int |
| wait_for_response(struct TCP_Server_Info *server, struct mid_q_entry *midQ) |
| { |
| int error; |
| |
| error = wait_event_freezekillable(server->response_q, |
| midQ->mid_state != MID_REQUEST_SUBMITTED); |
| if (error < 0) |
| return -ERESTARTSYS; |
| |
| return 0; |
| } |
| |
| 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 *)rqst->rq_iov[0].iov_base; |
| struct mid_q_entry *mid; |
| |
| /* enable signing if server requires it */ |
| if (server->sec_mode & (SECMODE_SIGN_REQUIRED | SECMODE_SIGN_ENABLED)) |
| hdr->Flags2 |= SMBFLG2_SECURITY_SIGNATURE; |
| |
| mid = AllocMidQEntry(hdr, server); |
| if (mid == NULL) |
| return ERR_PTR(-ENOMEM); |
| |
| rc = cifs_sign_rqst(rqst, server, &mid->sequence_number); |
| if (rc) { |
| DeleteMidQEntry(mid); |
| return ERR_PTR(rc); |
| } |
| |
| return mid; |
| } |
| |
| /* |
| * Send a SMB request and set the callback function in the mid to handle |
| * the result. Caller is responsible for dealing with timeouts. |
| */ |
| int |
| 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; |
| |
| timeout = flags & CIFS_TIMEOUT_MASK; |
| optype = flags & CIFS_OP_MASK; |
| |
| rc = wait_for_free_request(server, timeout, optype); |
| if (rc) |
| return rc; |
| |
| mutex_lock(&server->srv_mutex); |
| 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 PTR_ERR(mid); |
| } |
| |
| mid->receive = receive; |
| mid->callback = callback; |
| mid->callback_data = cbdata; |
| mid->mid_state = MID_REQUEST_SUBMITTED; |
| |
| /* put it on the pending_mid_q */ |
| spin_lock(&GlobalMid_Lock); |
| list_add_tail(&mid->qhead, &server->pending_mid_q); |
| spin_unlock(&GlobalMid_Lock); |
| |
| |
| cifs_in_send_inc(server); |
| rc = smb_send_rqst(server, rqst); |
| cifs_in_send_dec(server); |
| cifs_save_when_sent(mid); |
| |
| if (rc < 0) |
| server->sequence_number -= 2; |
| mutex_unlock(&server->srv_mutex); |
| |
| if (rc == 0) |
| return 0; |
| |
| cifs_delete_mid(mid); |
| add_credits(server, 1, optype); |
| wake_up(&server->request_q); |
| return rc; |
| } |
| |
| /* |
| * |
| * Send an SMB Request. No response info (other than return code) |
| * needs to be parsed. |
| * |
| * flags indicate the type of request buffer and how long to wait |
| * and whether to log NT STATUS code (error) before mapping it to POSIX error |
| * |
| */ |
| int |
| SendReceiveNoRsp(const unsigned int xid, struct cifs_ses *ses, |
| char *in_buf, int flags) |
| { |
| int rc; |
| struct kvec iov[1]; |
| int resp_buf_type; |
| |
| iov[0].iov_base = in_buf; |
| iov[0].iov_len = get_rfc1002_length(in_buf) + 4; |
| flags |= CIFS_NO_RESP; |
| rc = SendReceive2(xid, ses, iov, 1, &resp_buf_type, flags); |
| cifs_dbg(NOISY, "SendRcvNoRsp flags %d rc %d\n", flags, rc); |
| |
| return rc; |
| } |
| |
| static int |
| cifs_sync_mid_result(struct mid_q_entry *mid, struct TCP_Server_Info *server) |
| { |
| int rc = 0; |
| |
| cifs_dbg(FYI, "%s: cmd=%d mid=%llu state=%d\n", |
| __func__, le16_to_cpu(mid->command), mid->mid, mid->mid_state); |
| |
| spin_lock(&GlobalMid_Lock); |
| switch (mid->mid_state) { |
| case MID_RESPONSE_RECEIVED: |
| spin_unlock(&GlobalMid_Lock); |
| return rc; |
| case MID_RETRY_NEEDED: |
| rc = -EAGAIN; |
| break; |
| case MID_RESPONSE_MALFORMED: |
| rc = -EIO; |
| break; |
| case MID_SHUTDOWN: |
| rc = -EHOSTDOWN; |
| break; |
| default: |
| list_del_init(&mid->qhead); |
| cifs_dbg(VFS, "%s: invalid mid state mid=%llu state=%d\n", |
| __func__, mid->mid, mid->mid_state); |
| rc = -EIO; |
| } |
| spin_unlock(&GlobalMid_Lock); |
| |
| DeleteMidQEntry(mid); |
| return rc; |
| } |
| |
| static inline int |
| send_cancel(struct TCP_Server_Info *server, void *buf, struct mid_q_entry *mid) |
| { |
| return server->ops->send_cancel ? |
| server->ops->send_cancel(server, buf, mid) : 0; |
| } |
| |
| int |
| cifs_check_receive(struct mid_q_entry *mid, struct TCP_Server_Info *server, |
| bool log_error) |
| { |
| unsigned int len = get_rfc1002_length(mid->resp_buf) + 4; |
| |
| dump_smb(mid->resp_buf, min_t(u32, 92, len)); |
| |
| /* 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 */ |
| rc = cifs_verify_signature(&rqst, server, |
| mid->sequence_number + 1); |
| if (rc) |
| cifs_dbg(VFS, "SMB signature verification returned error = %d\n", |
| rc); |
| } |
| |
| /* BB special case reconnect tid and uid here? */ |
| return map_smb_to_linux_error(mid->resp_buf, log_error); |
| } |
| |
| struct mid_q_entry * |
| cifs_setup_request(struct cifs_ses *ses, struct smb_rqst *rqst) |
| { |
| int rc; |
| 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 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 |
| SendReceive2(const unsigned int xid, struct cifs_ses *ses, |
| struct kvec *iov, int n_vec, int *resp_buf_type /* ret */, |
| const int flags) |
| { |
| int rc = 0; |
| int timeout, optype; |
| 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; |
| |
| *resp_buf_type = CIFS_NO_BUFFER; /* no response buf yet */ |
| |
| if ((ses == NULL) || (ses->server == NULL)) { |
| cifs_small_buf_release(buf); |
| cifs_dbg(VFS, "Null session\n"); |
| return -EIO; |
| } |
| |
| if (ses->server->tcpStatus == CifsExiting) { |
| cifs_small_buf_release(buf); |
| return -ENOENT; |
| } |
| |
| /* |
| * Ensure that we do not send more than 50 overlapping requests |
| * to the same server. We may make this configurable later or |
| * use ses->maxReq. |
| */ |
| |
| rc = wait_for_free_request(ses->server, timeout, optype); |
| if (rc) { |
| cifs_small_buf_release(buf); |
| return rc; |
| } |
| |
| /* |
| * Make sure that we sign in the same order that we send on this socket |
| * and avoid races inside tcp sendmsg code that could cause corruption |
| * of smb data. |
| */ |
| |
| mutex_lock(&ses->server->srv_mutex); |
| |
| 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 PTR_ERR(midQ); |
| } |
| |
| midQ->mid_state = MID_REQUEST_SUBMITTED; |
| cifs_in_send_inc(ses->server); |
| rc = smb_sendv(ses->server, iov, n_vec); |
| cifs_in_send_dec(ses->server); |
| cifs_save_when_sent(midQ); |
| |
| if (rc < 0) |
| ses->server->sequence_number -= 2; |
| mutex_unlock(&ses->server->srv_mutex); |
| |
| if (rc < 0) { |
| cifs_small_buf_release(buf); |
| goto out; |
| } |
| |
| if (timeout == CIFS_ASYNC_OP) { |
| cifs_small_buf_release(buf); |
| goto out; |
| } |
| |
| rc = wait_for_response(ses->server, midQ); |
| if (rc != 0) { |
| send_cancel(ses->server, buf, midQ); |
| spin_lock(&GlobalMid_Lock); |
| if (midQ->mid_state == MID_REQUEST_SUBMITTED) { |
| midQ->callback = DeleteMidQEntry; |
| spin_unlock(&GlobalMid_Lock); |
| cifs_small_buf_release(buf); |
| add_credits(ses->server, 1, optype); |
| return rc; |
| } |
| spin_unlock(&GlobalMid_Lock); |
| } |
| |
| cifs_small_buf_release(buf); |
| |
| rc = cifs_sync_mid_result(midQ, ses->server); |
| if (rc != 0) { |
| add_credits(ses->server, 1, optype); |
| return rc; |
| } |
| |
| if (!midQ->resp_buf || midQ->mid_state != MID_RESPONSE_RECEIVED) { |
| rc = -EIO; |
| cifs_dbg(FYI, "Bad MID state?\n"); |
| goto out; |
| } |
| |
| buf = (char *)midQ->resp_buf; |
| iov[0].iov_base = buf; |
| iov[0].iov_len = get_rfc1002_length(buf) + 4; |
| if (midQ->large_buf) |
| *resp_buf_type = CIFS_LARGE_BUFFER; |
| else |
| *resp_buf_type = CIFS_SMALL_BUFFER; |
| |
| credits = ses->server->ops->get_credits(midQ); |
| |
| rc = ses->server->ops->check_receive(midQ, ses->server, |
| flags & CIFS_LOG_ERROR); |
| |
| /* mark it so buf will not be freed by cifs_delete_mid */ |
| if ((flags & CIFS_NO_RESP) == 0) |
| midQ->resp_buf = NULL; |
| out: |
| cifs_delete_mid(midQ); |
| add_credits(ses->server, credits, optype); |
| |
| return rc; |
| } |
| |
| int |
| SendReceive(const unsigned int xid, struct cifs_ses *ses, |
| struct smb_hdr *in_buf, struct smb_hdr *out_buf, |
| int *pbytes_returned, const int timeout) |
| { |
| int rc = 0; |
| struct mid_q_entry *midQ; |
| |
| if (ses == NULL) { |
| cifs_dbg(VFS, "Null smb session\n"); |
| return -EIO; |
| } |
| if (ses->server == NULL) { |
| cifs_dbg(VFS, "Null tcp session\n"); |
| return -EIO; |
| } |
| |
| if (ses->server->tcpStatus == CifsExiting) |
| return -ENOENT; |
| |
| /* Ensure that we do not send more than 50 overlapping requests |
| to the same server. We may make this configurable later or |
| use ses->maxReq */ |
| |
| if (be32_to_cpu(in_buf->smb_buf_length) > CIFSMaxBufSize + |
| MAX_CIFS_HDR_SIZE - 4) { |
| cifs_dbg(VFS, "Illegal length, greater than maximum frame, %d\n", |
| be32_to_cpu(in_buf->smb_buf_length)); |
| return -EIO; |
| } |
| |
| rc = wait_for_free_request(ses->server, timeout, 0); |
| if (rc) |
| return rc; |
| |
| /* make sure that we sign in the same order that we send on this socket |
| and avoid races inside tcp sendmsg code that could cause corruption |
| of smb data */ |
| |
| mutex_lock(&ses->server->srv_mutex); |
| |
| rc = allocate_mid(ses, in_buf, &midQ); |
| if (rc) { |
| mutex_unlock(&ses->server->srv_mutex); |
| /* Update # of requests on wire to server */ |
| add_credits(ses->server, 1, 0); |
| return rc; |
| } |
| |
| rc = cifs_sign_smb(in_buf, ses->server, &midQ->sequence_number); |
| if (rc) { |
| mutex_unlock(&ses->server->srv_mutex); |
| goto out; |
| } |
| |
| midQ->mid_state = MID_REQUEST_SUBMITTED; |
| |
| cifs_in_send_inc(ses->server); |
| rc = smb_send(ses->server, in_buf, be32_to_cpu(in_buf->smb_buf_length)); |
| cifs_in_send_dec(ses->server); |
| cifs_save_when_sent(midQ); |
| |
| if (rc < 0) |
| ses->server->sequence_number -= 2; |
| |
| mutex_unlock(&ses->server->srv_mutex); |
| |
| if (rc < 0) |
| goto out; |
| |
| if (timeout == CIFS_ASYNC_OP) |
| goto out; |
| |
| rc = wait_for_response(ses->server, midQ); |
| if (rc != 0) { |
| send_cancel(ses->server, in_buf, midQ); |
| spin_lock(&GlobalMid_Lock); |
| if (midQ->mid_state == MID_REQUEST_SUBMITTED) { |
| /* no longer considered to be "in-flight" */ |
| midQ->callback = DeleteMidQEntry; |
| spin_unlock(&GlobalMid_Lock); |
| add_credits(ses->server, 1, 0); |
| return rc; |
| } |
| spin_unlock(&GlobalMid_Lock); |
| } |
| |
| rc = cifs_sync_mid_result(midQ, ses->server); |
| if (rc != 0) { |
| add_credits(ses->server, 1, 0); |
| return rc; |
| } |
| |
| if (!midQ->resp_buf || !out_buf || |
| midQ->mid_state != MID_RESPONSE_RECEIVED) { |
| rc = -EIO; |
| cifs_dbg(VFS, "Bad MID state?\n"); |
| goto out; |
| } |
| |
| *pbytes_returned = get_rfc1002_length(midQ->resp_buf); |
| memcpy(out_buf, midQ->resp_buf, *pbytes_returned + 4); |
| rc = cifs_check_receive(midQ, ses->server, 0); |
| out: |
| cifs_delete_mid(midQ); |
| add_credits(ses->server, 1, 0); |
| |
| return rc; |
| } |
| |
| /* We send a LOCKINGX_CANCEL_LOCK to cause the Windows |
| blocking lock to return. */ |
| |
| static int |
| send_lock_cancel(const unsigned int xid, struct cifs_tcon *tcon, |
| struct smb_hdr *in_buf, |
| struct smb_hdr *out_buf) |
| { |
| int bytes_returned; |
| struct cifs_ses *ses = tcon->ses; |
| LOCK_REQ *pSMB = (LOCK_REQ *)in_buf; |
| |
| /* We just modify the current in_buf to change |
| the type of lock from LOCKING_ANDX_SHARED_LOCK |
| or LOCKING_ANDX_EXCLUSIVE_LOCK to |
| LOCKING_ANDX_CANCEL_LOCK. */ |
| |
| pSMB->LockType = LOCKING_ANDX_CANCEL_LOCK|LOCKING_ANDX_LARGE_FILES; |
| pSMB->Timeout = 0; |
| pSMB->hdr.Mid = get_next_mid(ses->server); |
| |
| return SendReceive(xid, ses, in_buf, out_buf, |
| &bytes_returned, 0); |
| } |
| |
| int |
| SendReceiveBlockingLock(const unsigned int xid, struct cifs_tcon *tcon, |
| struct smb_hdr *in_buf, struct smb_hdr *out_buf, |
| int *pbytes_returned) |
| { |
| int rc = 0; |
| int rstart = 0; |
| struct mid_q_entry *midQ; |
| struct cifs_ses *ses; |
| |
| if (tcon == NULL || tcon->ses == NULL) { |
| cifs_dbg(VFS, "Null smb session\n"); |
| return -EIO; |
| } |
| ses = tcon->ses; |
| |
| if (ses->server == NULL) { |
| cifs_dbg(VFS, "Null tcp session\n"); |
| return -EIO; |
| } |
| |
| if (ses->server->tcpStatus == CifsExiting) |
| return -ENOENT; |
| |
| /* Ensure that we do not send more than 50 overlapping requests |
| to the same server. We may make this configurable later or |
| use ses->maxReq */ |
| |
| if (be32_to_cpu(in_buf->smb_buf_length) > CIFSMaxBufSize + |
| MAX_CIFS_HDR_SIZE - 4) { |
| cifs_dbg(VFS, "Illegal length, greater than maximum frame, %d\n", |
| be32_to_cpu(in_buf->smb_buf_length)); |
| return -EIO; |
| } |
| |
| rc = wait_for_free_request(ses->server, CIFS_BLOCKING_OP, 0); |
| if (rc) |
| return rc; |
| |
| /* make sure that we sign in the same order that we send on this socket |
| and avoid races inside tcp sendmsg code that could cause corruption |
| of smb data */ |
| |
| mutex_lock(&ses->server->srv_mutex); |
| |
| rc = allocate_mid(ses, in_buf, &midQ); |
| if (rc) { |
| mutex_unlock(&ses->server->srv_mutex); |
| return rc; |
| } |
| |
| rc = cifs_sign_smb(in_buf, ses->server, &midQ->sequence_number); |
| if (rc) { |
| cifs_delete_mid(midQ); |
| mutex_unlock(&ses->server->srv_mutex); |
| return rc; |
| } |
| |
| midQ->mid_state = MID_REQUEST_SUBMITTED; |
| cifs_in_send_inc(ses->server); |
| rc = smb_send(ses->server, in_buf, be32_to_cpu(in_buf->smb_buf_length)); |
| cifs_in_send_dec(ses->server); |
| cifs_save_when_sent(midQ); |
| |
| if (rc < 0) |
| ses->server->sequence_number -= 2; |
| |
| mutex_unlock(&ses->server->srv_mutex); |
| |
| if (rc < 0) { |
| cifs_delete_mid(midQ); |
| return rc; |
| } |
| |
| /* Wait for a reply - allow signals to interrupt. */ |
| rc = wait_event_interruptible(ses->server->response_q, |
| (!(midQ->mid_state == MID_REQUEST_SUBMITTED)) || |
| ((ses->server->tcpStatus != CifsGood) && |
| (ses->server->tcpStatus != CifsNew))); |
| |
| /* Were we interrupted by a signal ? */ |
| if ((rc == -ERESTARTSYS) && |
| (midQ->mid_state == MID_REQUEST_SUBMITTED) && |
| ((ses->server->tcpStatus == CifsGood) || |
| (ses->server->tcpStatus == CifsNew))) { |
| |
| if (in_buf->Command == SMB_COM_TRANSACTION2) { |
| /* POSIX lock. We send a NT_CANCEL SMB to cause the |
| blocking lock to return. */ |
| rc = send_cancel(ses->server, in_buf, midQ); |
| if (rc) { |
| cifs_delete_mid(midQ); |
| return rc; |
| } |
| } else { |
| /* Windows lock. We send a LOCKINGX_CANCEL_LOCK |
| to cause the blocking lock to return. */ |
| |
| rc = send_lock_cancel(xid, tcon, in_buf, out_buf); |
| |
| /* If we get -ENOLCK back the lock may have |
| already been removed. Don't exit in this case. */ |
| if (rc && rc != -ENOLCK) { |
| cifs_delete_mid(midQ); |
| return rc; |
| } |
| } |
| |
| rc = wait_for_response(ses->server, midQ); |
| if (rc) { |
| send_cancel(ses->server, in_buf, midQ); |
| spin_lock(&GlobalMid_Lock); |
| if (midQ->mid_state == MID_REQUEST_SUBMITTED) { |
| /* no longer considered to be "in-flight" */ |
| midQ->callback = DeleteMidQEntry; |
| spin_unlock(&GlobalMid_Lock); |
| return rc; |
| } |
| spin_unlock(&GlobalMid_Lock); |
| } |
| |
| /* We got the response - restart system call. */ |
| rstart = 1; |
| } |
| |
| rc = cifs_sync_mid_result(midQ, ses->server); |
| if (rc != 0) |
| return rc; |
| |
| /* rcvd frame is ok */ |
| if (out_buf == NULL || midQ->mid_state != MID_RESPONSE_RECEIVED) { |
| rc = -EIO; |
| cifs_dbg(VFS, "Bad MID state?\n"); |
| goto out; |
| } |
| |
| *pbytes_returned = get_rfc1002_length(midQ->resp_buf); |
| memcpy(out_buf, midQ->resp_buf, *pbytes_returned + 4); |
| rc = cifs_check_receive(midQ, ses->server, 0); |
| out: |
| cifs_delete_mid(midQ); |
| if (rstart && rc == -EACCES) |
| return -ERESTARTSYS; |
| return rc; |
| } |