diff options
Diffstat (limited to 'fs/cifs/transport.c')
-rw-r--r-- | fs/cifs/transport.c | 427 |
1 files changed, 203 insertions, 224 deletions
diff --git a/fs/cifs/transport.c b/fs/cifs/transport.c index 59ca81b16919..c8e2808cd5e6 100644 --- a/fs/cifs/transport.c +++ b/fs/cifs/transport.c @@ -36,7 +36,13 @@ extern mempool_t *cifs_mid_poolp; -static struct mid_q_entry * +static void +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; @@ -58,28 +64,28 @@ AllocMidQEntry(const struct smb_hdr *smb_buffer, struct TCP_Server_Info *server) /* do_gettimeofday(&temp->when_sent);*/ /* easier to use jiffies */ /* when mid allocated can be before when sent */ temp->when_alloc = jiffies; - temp->tsk = current; + + /* + * The default is for the mid to be synchronous, so the + * default callback just wakes up the current task. + */ + temp->callback = wake_up_task; + temp->callback_data = current; } - spin_lock(&GlobalMid_Lock); - list_add_tail(&temp->qhead, &server->pending_mid_q); atomic_inc(&midCount); temp->midState = MID_REQUEST_ALLOCATED; - spin_unlock(&GlobalMid_Lock); return temp; } -static void +void DeleteMidQEntry(struct mid_q_entry *midEntry) { #ifdef CONFIG_CIFS_STATS2 unsigned long now; #endif - spin_lock(&GlobalMid_Lock); midEntry->midState = MID_FREE; - list_del(&midEntry->qhead); atomic_dec(&midCount); - spin_unlock(&GlobalMid_Lock); if (midEntry->largeBuf) cifs_buf_release(midEntry->resp_buf); else @@ -103,6 +109,16 @@ DeleteMidQEntry(struct mid_q_entry *midEntry) mempool_free(midEntry, cifs_mid_poolp); } +static void +delete_mid(struct mid_q_entry *mid) +{ + spin_lock(&GlobalMid_Lock); + list_del(&mid->qhead); + spin_unlock(&GlobalMid_Lock); + + DeleteMidQEntry(mid); +} + static int smb_sendv(struct TCP_Server_Info *server, struct kvec *iov, int n_vec) { @@ -244,31 +260,31 @@ smb_send(struct TCP_Server_Info *server, struct smb_hdr *smb_buffer, return smb_sendv(server, &iov, 1); } -static int wait_for_free_request(struct cifsSesInfo *ses, const int long_op) +static int wait_for_free_request(struct TCP_Server_Info *server, + const int long_op) { if (long_op == CIFS_ASYNC_OP) { /* oplock breaks must not be held up */ - atomic_inc(&ses->server->inFlight); + atomic_inc(&server->inFlight); return 0; } spin_lock(&GlobalMid_Lock); while (1) { - if (atomic_read(&ses->server->inFlight) >= - cifs_max_pending){ + if (atomic_read(&server->inFlight) >= cifs_max_pending) { spin_unlock(&GlobalMid_Lock); #ifdef CONFIG_CIFS_STATS2 - atomic_inc(&ses->server->num_waiters); + atomic_inc(&server->num_waiters); #endif - wait_event(ses->server->request_q, - atomic_read(&ses->server->inFlight) + wait_event(server->request_q, + atomic_read(&server->inFlight) < cifs_max_pending); #ifdef CONFIG_CIFS_STATS2 - atomic_dec(&ses->server->num_waiters); + atomic_dec(&server->num_waiters); #endif spin_lock(&GlobalMid_Lock); } else { - if (ses->server->tcpStatus == CifsExiting) { + if (server->tcpStatus == CifsExiting) { spin_unlock(&GlobalMid_Lock); return -ENOENT; } @@ -278,7 +294,7 @@ static int wait_for_free_request(struct cifsSesInfo *ses, const int long_op) /* update # of requests on the wire to server */ if (long_op != CIFS_BLOCKING_OP) - atomic_inc(&ses->server->inFlight); + atomic_inc(&server->inFlight); spin_unlock(&GlobalMid_Lock); break; } @@ -308,53 +324,81 @@ static int allocate_mid(struct cifsSesInfo *ses, struct smb_hdr *in_buf, *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 cifsSesInfo *ses, - struct mid_q_entry *midQ, - unsigned long timeout, - unsigned long time_to_wait) +static int +wait_for_response(struct TCP_Server_Info *server, struct mid_q_entry *midQ) { - unsigned long curr_timeout; + int error; - for (;;) { - curr_timeout = timeout + jiffies; - wait_event_timeout(ses->server->response_q, - midQ->midState != MID_REQUEST_SUBMITTED, timeout); + error = wait_event_killable(server->response_q, + midQ->midState != MID_REQUEST_SUBMITTED); + if (error < 0) + return -ERESTARTSYS; - if (time_after(jiffies, curr_timeout) && - (midQ->midState == MID_REQUEST_SUBMITTED) && - ((ses->server->tcpStatus == CifsGood) || - (ses->server->tcpStatus == CifsNew))) { + return 0; +} - unsigned long lrt; - /* We timed out. Is the server still - sending replies ? */ - spin_lock(&GlobalMid_Lock); - lrt = ses->server->lstrp; - spin_unlock(&GlobalMid_Lock); +/* + * 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_hdr *in_buf, + mid_callback_t *callback, void *cbdata) +{ + int rc; + struct mid_q_entry *mid; - /* Calculate time_to_wait past last receive time. - Although we prefer not to time out if the - server is still responding - we will time - out if the server takes more than 15 (or 45 - or 180) seconds to respond to this request - and has not responded to any request from - other threads on the client within 10 seconds */ - lrt += time_to_wait; - if (time_after(jiffies, lrt)) { - /* No replies for time_to_wait. */ - cERROR(1, "server not responding"); - return -1; - } - } else { - return 0; - } + rc = wait_for_free_request(server, CIFS_ASYNC_OP); + if (rc) + return rc; + + mutex_lock(&server->srv_mutex); + mid = AllocMidQEntry(in_buf, server); + if (mid == NULL) { + mutex_unlock(&server->srv_mutex); + return -ENOMEM; } -} + /* put it on the pending_mid_q */ + spin_lock(&GlobalMid_Lock); + list_add_tail(&mid->qhead, &server->pending_mid_q); + spin_unlock(&GlobalMid_Lock); + + rc = cifs_sign_smb(in_buf, server, &mid->sequence_number); + if (rc) { + mutex_unlock(&server->srv_mutex); + goto out_err; + } + + mid->callback = callback; + mid->callback_data = cbdata; + mid->midState = MID_REQUEST_SUBMITTED; +#ifdef CONFIG_CIFS_STATS2 + atomic_inc(&server->inSend); +#endif + rc = smb_send(server, in_buf, in_buf->smb_buf_length); +#ifdef CONFIG_CIFS_STATS2 + atomic_dec(&server->inSend); + mid->when_sent = jiffies; +#endif + mutex_unlock(&server->srv_mutex); + if (rc) + goto out_err; + + return rc; +out_err: + delete_mid(mid); + atomic_dec(&server->inFlight); + wake_up(&server->request_q); + return rc; +} /* * @@ -382,6 +426,81 @@ SendReceiveNoRsp(const unsigned int xid, struct cifsSesInfo *ses, return rc; } +static int +sync_mid_result(struct mid_q_entry *mid, struct TCP_Server_Info *server) +{ + int rc = 0; + + cFYI(1, "%s: cmd=%d mid=%d state=%d", __func__, mid->command, + mid->mid, mid->midState); + + spin_lock(&GlobalMid_Lock); + /* ensure that it's no longer on the pending_mid_q */ + list_del_init(&mid->qhead); + + switch (mid->midState) { + case MID_RESPONSE_RECEIVED: + spin_unlock(&GlobalMid_Lock); + return rc; + case MID_REQUEST_SUBMITTED: + /* socket is going down, reject all calls */ + if (server->tcpStatus == CifsExiting) { + cERROR(1, "%s: canceling mid=%d cmd=0x%x state=%d", + __func__, mid->mid, mid->command, mid->midState); + rc = -EHOSTDOWN; + break; + } + case MID_RETRY_NEEDED: + rc = -EAGAIN; + break; + default: + cERROR(1, "%s: invalid mid state mid=%d state=%d", __func__, + mid->mid, mid->midState); + rc = -EIO; + } + spin_unlock(&GlobalMid_Lock); + + DeleteMidQEntry(mid); + return rc; +} + +/* + * An NT cancel request header looks just like the original request except: + * + * The Command is SMB_COM_NT_CANCEL + * The WordCount is zeroed out + * The ByteCount is zeroed out + * + * This function mangles an existing request buffer into a + * SMB_COM_NT_CANCEL request and then sends it. + */ +static int +send_nt_cancel(struct TCP_Server_Info *server, struct smb_hdr *in_buf, + struct mid_q_entry *mid) +{ + int rc = 0; + + /* -4 for RFC1001 length and +2 for BCC field */ + in_buf->smb_buf_length = sizeof(struct smb_hdr) - 4 + 2; + in_buf->Command = SMB_COM_NT_CANCEL; + in_buf->WordCount = 0; + BCC_LE(in_buf) = 0; + + mutex_lock(&server->srv_mutex); + rc = cifs_sign_smb(in_buf, server, &mid->sequence_number); + if (rc) { + mutex_unlock(&server->srv_mutex); + return rc; + } + rc = smb_send(server, in_buf, in_buf->smb_buf_length); + mutex_unlock(&server->srv_mutex); + + cFYI(1, "issued NT_CANCEL for mid %u, rc = %d", + in_buf->Mid, rc); + + return rc; +} + int SendReceive2(const unsigned int xid, struct cifsSesInfo *ses, struct kvec *iov, int n_vec, int *pRespBufType /* ret */, @@ -390,7 +509,6 @@ SendReceive2(const unsigned int xid, struct cifsSesInfo *ses, int rc = 0; int long_op; unsigned int receive_len; - unsigned long timeout; struct mid_q_entry *midQ; struct smb_hdr *in_buf = iov[0].iov_base; @@ -413,7 +531,7 @@ SendReceive2(const unsigned int xid, struct cifsSesInfo *ses, to the same server. We may make this configurable later or use ses->maxReq */ - rc = wait_for_free_request(ses, long_op); + rc = wait_for_free_request(ses->server, long_op); if (rc) { cifs_small_buf_release(in_buf); return rc; @@ -457,65 +575,20 @@ SendReceive2(const unsigned int xid, struct cifsSesInfo *ses, if (rc < 0) goto out; - if (long_op == CIFS_STD_OP) - timeout = 15 * HZ; - else if (long_op == CIFS_VLONG_OP) /* e.g. slow writes past EOF */ - timeout = 180 * HZ; - else if (long_op == CIFS_LONG_OP) - timeout = 45 * HZ; /* should be greater than - servers oplock break timeout (about 43 seconds) */ - else if (long_op == CIFS_ASYNC_OP) + if (long_op == CIFS_ASYNC_OP) goto out; - else if (long_op == CIFS_BLOCKING_OP) - timeout = 0x7FFFFFFF; /* large, but not so large as to wrap */ - else { - cERROR(1, "unknown timeout flag %d", long_op); - rc = -EIO; - goto out; - } - - /* wait for 15 seconds or until woken up due to response arriving or - due to last connection to this server being unmounted */ - if (signal_pending(current)) { - /* if signal pending do not hold up user for full smb timeout - but we still give response a chance to complete */ - timeout = 2 * HZ; - } - - /* No user interrupts in wait - wreaks havoc with performance */ - wait_for_response(ses, midQ, timeout, 10 * HZ); - - spin_lock(&GlobalMid_Lock); - if (midQ->resp_buf == NULL) { - cERROR(1, "No response to cmd %d mid %d", - midQ->command, midQ->mid); - if (midQ->midState == MID_REQUEST_SUBMITTED) { - if (ses->server->tcpStatus == CifsExiting) - rc = -EHOSTDOWN; - else { - ses->server->tcpStatus = CifsNeedReconnect; - midQ->midState = MID_RETRY_NEEDED; - } - } + rc = wait_for_response(ses->server, midQ); + if (rc != 0) + goto out; - if (rc != -EHOSTDOWN) { - if (midQ->midState == MID_RETRY_NEEDED) { - rc = -EAGAIN; - cFYI(1, "marking request for retry"); - } else { - rc = -EIO; - } - } - spin_unlock(&GlobalMid_Lock); - DeleteMidQEntry(midQ); - /* Update # of requests on wire to server */ + rc = sync_mid_result(midQ, ses->server); + if (rc != 0) { atomic_dec(&ses->server->inFlight); wake_up(&ses->server->request_q); return rc; } - spin_unlock(&GlobalMid_Lock); receive_len = midQ->resp_buf->smb_buf_length; if (receive_len > CIFSMaxBufSize + MAX_CIFS_HDR_SIZE) { @@ -564,14 +637,14 @@ SendReceive2(const unsigned int xid, struct cifsSesInfo *ses, if ((flags & CIFS_NO_RESP) == 0) midQ->resp_buf = NULL; /* mark it so buf will not be freed by - DeleteMidQEntry */ + delete_mid */ } else { rc = -EIO; cFYI(1, "Bad MID state?"); } out: - DeleteMidQEntry(midQ); + delete_mid(midQ); atomic_dec(&ses->server->inFlight); wake_up(&ses->server->request_q); @@ -585,7 +658,6 @@ SendReceive(const unsigned int xid, struct cifsSesInfo *ses, { int rc = 0; unsigned int receive_len; - unsigned long timeout; struct mid_q_entry *midQ; if (ses == NULL) { @@ -610,7 +682,7 @@ SendReceive(const unsigned int xid, struct cifsSesInfo *ses, return -EIO; } - rc = wait_for_free_request(ses, long_op); + rc = wait_for_free_request(ses->server, long_op); if (rc) return rc; @@ -649,64 +721,20 @@ SendReceive(const unsigned int xid, struct cifsSesInfo *ses, if (rc < 0) goto out; - if (long_op == CIFS_STD_OP) - timeout = 15 * HZ; - /* wait for 15 seconds or until woken up due to response arriving or - due to last connection to this server being unmounted */ - else if (long_op == CIFS_ASYNC_OP) + if (long_op == CIFS_ASYNC_OP) goto out; - else if (long_op == CIFS_VLONG_OP) /* writes past EOF can be slow */ - timeout = 180 * HZ; - else if (long_op == CIFS_LONG_OP) - timeout = 45 * HZ; /* should be greater than - servers oplock break timeout (about 43 seconds) */ - else if (long_op == CIFS_BLOCKING_OP) - timeout = 0x7FFFFFFF; /* large but no so large as to wrap */ - else { - cERROR(1, "unknown timeout flag %d", long_op); - rc = -EIO; - goto out; - } - if (signal_pending(current)) { - /* if signal pending do not hold up user for full smb timeout - but we still give response a chance to complete */ - timeout = 2 * HZ; - } - - /* No user interrupts in wait - wreaks havoc with performance */ - wait_for_response(ses, midQ, timeout, 10 * HZ); - - spin_lock(&GlobalMid_Lock); - if (midQ->resp_buf == NULL) { - cERROR(1, "No response for cmd %d mid %d", - midQ->command, midQ->mid); - if (midQ->midState == MID_REQUEST_SUBMITTED) { - if (ses->server->tcpStatus == CifsExiting) - rc = -EHOSTDOWN; - else { - ses->server->tcpStatus = CifsNeedReconnect; - midQ->midState = MID_RETRY_NEEDED; - } - } + rc = wait_for_response(ses->server, midQ); + if (rc != 0) + goto out; - if (rc != -EHOSTDOWN) { - if (midQ->midState == MID_RETRY_NEEDED) { - rc = -EAGAIN; - cFYI(1, "marking request for retry"); - } else { - rc = -EIO; - } - } - spin_unlock(&GlobalMid_Lock); - DeleteMidQEntry(midQ); - /* Update # of requests on wire to server */ + rc = sync_mid_result(midQ, ses->server); + if (rc != 0) { atomic_dec(&ses->server->inFlight); wake_up(&ses->server->request_q); return rc; } - spin_unlock(&GlobalMid_Lock); receive_len = midQ->resp_buf->smb_buf_length; if (receive_len > CIFSMaxBufSize + MAX_CIFS_HDR_SIZE) { @@ -755,36 +783,13 @@ SendReceive(const unsigned int xid, struct cifsSesInfo *ses, } out: - DeleteMidQEntry(midQ); + delete_mid(midQ); atomic_dec(&ses->server->inFlight); wake_up(&ses->server->request_q); return rc; } -/* Send an NT_CANCEL SMB to cause the POSIX blocking lock to return. */ - -static int -send_nt_cancel(struct cifsTconInfo *tcon, struct smb_hdr *in_buf, - struct mid_q_entry *midQ) -{ - int rc = 0; - struct cifsSesInfo *ses = tcon->ses; - __u16 mid = in_buf->Mid; - - header_assemble(in_buf, SMB_COM_NT_CANCEL, tcon, 0); - in_buf->Mid = mid; - mutex_lock(&ses->server->srv_mutex); - rc = cifs_sign_smb(in_buf, ses->server, &midQ->sequence_number); - if (rc) { - mutex_unlock(&ses->server->srv_mutex); - return rc; - } - rc = smb_send(ses->server, in_buf, in_buf->smb_buf_length); - mutex_unlock(&ses->server->srv_mutex); - return rc; -} - /* We send a LOCKINGX_CANCEL_LOCK to cause the Windows blocking lock to return. */ @@ -807,7 +812,7 @@ send_lock_cancel(const unsigned int xid, struct cifsTconInfo *tcon, pSMB->hdr.Mid = GetNextMid(ses->server); return SendReceive(xid, ses, in_buf, out_buf, - &bytes_returned, CIFS_STD_OP); + &bytes_returned, 0); } int @@ -845,7 +850,7 @@ SendReceiveBlockingLock(const unsigned int xid, struct cifsTconInfo *tcon, return -EIO; } - rc = wait_for_free_request(ses, CIFS_BLOCKING_OP); + rc = wait_for_free_request(ses->server, CIFS_BLOCKING_OP); if (rc) return rc; @@ -863,7 +868,7 @@ SendReceiveBlockingLock(const unsigned int xid, struct cifsTconInfo *tcon, rc = cifs_sign_smb(in_buf, ses->server, &midQ->sequence_number); if (rc) { - DeleteMidQEntry(midQ); + delete_mid(midQ); mutex_unlock(&ses->server->srv_mutex); return rc; } @@ -880,7 +885,7 @@ SendReceiveBlockingLock(const unsigned int xid, struct cifsTconInfo *tcon, mutex_unlock(&ses->server->srv_mutex); if (rc < 0) { - DeleteMidQEntry(midQ); + delete_mid(midQ); return rc; } @@ -899,10 +904,9 @@ SendReceiveBlockingLock(const unsigned int xid, struct cifsTconInfo *tcon, if (in_buf->Command == SMB_COM_TRANSACTION2) { /* POSIX lock. We send a NT_CANCEL SMB to cause the blocking lock to return. */ - - rc = send_nt_cancel(tcon, in_buf, midQ); + rc = send_nt_cancel(ses->server, in_buf, midQ); if (rc) { - DeleteMidQEntry(midQ); + delete_mid(midQ); return rc; } } else { @@ -914,47 +918,22 @@ SendReceiveBlockingLock(const unsigned int xid, struct cifsTconInfo *tcon, /* If we get -ENOLCK back the lock may have already been removed. Don't exit in this case. */ if (rc && rc != -ENOLCK) { - DeleteMidQEntry(midQ); + delete_mid(midQ); return rc; } } - /* Wait 5 seconds for the response. */ - if (wait_for_response(ses, midQ, 5 * HZ, 5 * HZ) == 0) { + if (wait_for_response(ses->server, midQ) == 0) { /* We got the response - restart system call. */ rstart = 1; } } - spin_lock(&GlobalMid_Lock); - if (midQ->resp_buf) { - spin_unlock(&GlobalMid_Lock); - receive_len = midQ->resp_buf->smb_buf_length; - } else { - cERROR(1, "No response for cmd %d mid %d", - midQ->command, midQ->mid); - if (midQ->midState == MID_REQUEST_SUBMITTED) { - if (ses->server->tcpStatus == CifsExiting) - rc = -EHOSTDOWN; - else { - ses->server->tcpStatus = CifsNeedReconnect; - midQ->midState = MID_RETRY_NEEDED; - } - } - - if (rc != -EHOSTDOWN) { - if (midQ->midState == MID_RETRY_NEEDED) { - rc = -EAGAIN; - cFYI(1, "marking request for retry"); - } else { - rc = -EIO; - } - } - spin_unlock(&GlobalMid_Lock); - DeleteMidQEntry(midQ); + rc = sync_mid_result(midQ, ses->server); + if (rc != 0) return rc; - } + receive_len = midQ->resp_buf->smb_buf_length; if (receive_len > CIFSMaxBufSize + MAX_CIFS_HDR_SIZE) { cERROR(1, "Frame too large received. Length: %d Xid: %d", receive_len, xid); @@ -1001,7 +980,7 @@ SendReceiveBlockingLock(const unsigned int xid, struct cifsTconInfo *tcon, BCC(out_buf) = le16_to_cpu(BCC_LE(out_buf)); out: - DeleteMidQEntry(midQ); + delete_mid(midQ); if (rstart && rc == -EACCES) return -ERESTARTSYS; return rc; |