summaryrefslogtreecommitdiff
path: root/fs/cifs/transport.c
diff options
context:
space:
mode:
Diffstat (limited to 'fs/cifs/transport.c')
-rw-r--r--fs/cifs/transport.c427
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;