From e636c8d336489bf3eed5878299e6cc045bbad077 Mon Sep 17 00:00:00 2001
From: hc <hc@nodka.com>
Date: Tue, 20 Feb 2024 01:17:29 +0000
Subject: [PATCH] debug lk
---
kernel/fs/cifs/transport.c | 721 +++++++++++++++++++++++++++++++++++++-----------------
1 files changed, 490 insertions(+), 231 deletions(-)
diff --git a/kernel/fs/cifs/transport.c b/kernel/fs/cifs/transport.c
index 59643ac..4409f56 100644
--- a/kernel/fs/cifs/transport.c
+++ b/kernel/fs/cifs/transport.c
@@ -33,6 +33,7 @@
#include <linux/uaccess.h>
#include <asm/processor.h>
#include <linux/mempool.h>
+#include <linux/sched/signal.h>
#include "cifspdu.h"
#include "cifsglob.h"
#include "cifsproto.h"
@@ -75,6 +76,8 @@
* The default is for the mid to be synchronous, so the
* default callback just wakes up the current task.
*/
+ get_task_struct(current);
+ temp->creator = current;
temp->callback = cifs_wake_up_task;
temp->callback_data = current;
@@ -85,10 +88,81 @@
static void _cifs_mid_q_entry_release(struct kref *refcount)
{
- struct mid_q_entry *mid = container_of(refcount, struct mid_q_entry,
- refcount);
+ struct mid_q_entry *midEntry =
+ container_of(refcount, struct mid_q_entry, refcount);
+#ifdef CONFIG_CIFS_STATS2
+ __le16 command = midEntry->server->vals->lock_cmd;
+ __u16 smb_cmd = le16_to_cpu(midEntry->command);
+ unsigned long now;
+ unsigned long roundtrip_time;
+#endif
+ struct TCP_Server_Info *server = midEntry->server;
- mempool_free(mid, cifs_mid_poolp);
+ if (midEntry->resp_buf && (midEntry->mid_flags & MID_WAIT_CANCELLED) &&
+ midEntry->mid_state == MID_RESPONSE_RECEIVED &&
+ server->ops->handle_cancelled_mid)
+ server->ops->handle_cancelled_mid(midEntry, server);
+
+ 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;
+ if (now < midEntry->when_alloc)
+ cifs_server_dbg(VFS, "Invalid mid allocation time\n");
+ roundtrip_time = now - midEntry->when_alloc;
+
+ if (smb_cmd < NUMBER_OF_SMB2_COMMANDS) {
+ if (atomic_read(&server->num_cmds[smb_cmd]) == 0) {
+ server->slowest_cmd[smb_cmd] = roundtrip_time;
+ server->fastest_cmd[smb_cmd] = roundtrip_time;
+ } else {
+ if (server->slowest_cmd[smb_cmd] < roundtrip_time)
+ server->slowest_cmd[smb_cmd] = roundtrip_time;
+ else if (server->fastest_cmd[smb_cmd] > roundtrip_time)
+ server->fastest_cmd[smb_cmd] = roundtrip_time;
+ }
+ cifs_stats_inc(&server->num_cmds[smb_cmd]);
+ server->time_per_cmd[smb_cmd] += roundtrip_time;
+ }
+ /*
+ * commands taking longer than one second (default) can be indications
+ * that something is wrong, unless it is quite a slow link or a very
+ * busy server. Note that this calc is unlikely or impossible to wrap
+ * as long as slow_rsp_threshold is not set way above recommended max
+ * value (32767 ie 9 hours) and is generally harmless even if wrong
+ * since only affects debug counters - so leaving the calc as simple
+ * comparison rather than doing multiple conversions and overflow
+ * checks
+ */
+ if ((slow_rsp_threshold != 0) &&
+ time_after(now, midEntry->when_alloc + (slow_rsp_threshold * HZ)) &&
+ (midEntry->command != command)) {
+ /*
+ * smb2slowcmd[NUMBER_OF_SMB2_COMMANDS] counts by command
+ * NB: le16_to_cpu returns unsigned so can not be negative below
+ */
+ if (smb_cmd < NUMBER_OF_SMB2_COMMANDS)
+ cifs_stats_inc(&server->smb2slowcmd[smb_cmd]);
+
+ trace_smb3_slow_rsp(smb_cmd, midEntry->mid, midEntry->pid,
+ midEntry->when_sent, midEntry->when_received);
+ if (cifsFYI & CIFS_TIMER) {
+ pr_debug("slow rsp: cmd %d mid %llu",
+ midEntry->command, midEntry->mid);
+ cifs_info("A: 0x%lx S: 0x%lx R: 0x%lx\n",
+ now - midEntry->when_alloc,
+ now - midEntry->when_sent,
+ now - midEntry->when_received);
+ }
+ }
+#endif
+ put_task_struct(midEntry->creator);
+
+ mempool_free(midEntry, cifs_mid_poolp);
}
void cifs_mid_q_entry_release(struct mid_q_entry *midEntry)
@@ -98,43 +172,8 @@
spin_unlock(&GlobalMid_Lock);
}
-void
-DeleteMidQEntry(struct mid_q_entry *midEntry)
+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 (time_after(now, midEntry->when_alloc + HZ) &&
- (midEntry->command != command)) {
- /* smb2slowcmd[NUMBER_OF_SMB2_COMMANDS] counts by command */
- if ((le16_to_cpu(midEntry->command) < NUMBER_OF_SMB2_COMMANDS) &&
- (le16_to_cpu(midEntry->command) >= 0))
- cifs_stats_inc(&midEntry->server->smb2slowcmd[le16_to_cpu(midEntry->command)]);
-
- trace_smb3_slow_rsp(le16_to_cpu(midEntry->command),
- midEntry->mid, midEntry->pid,
- midEntry->when_sent, midEntry->when_received);
- if (cifsFYI & CIFS_TIMER) {
- pr_debug(" CIFS slow rsp: cmd %d mid %llu",
- midEntry->command, midEntry->mid);
- pr_info(" A: 0x%lx S: 0x%lx R: 0x%lx\n",
- now - midEntry->when_alloc,
- now - midEntry->when_sent,
- now - midEntry->when_received);
- }
- }
-#endif
cifs_mid_q_entry_release(midEntry);
}
@@ -142,8 +181,10 @@
cifs_delete_mid(struct mid_q_entry *mid)
{
spin_lock(&GlobalMid_Lock);
- list_del_init(&mid->qhead);
- mid->mid_flags |= MID_DELETED;
+ if (!(mid->mid_flags & MID_DELETED)) {
+ list_del_init(&mid->qhead);
+ mid->mid_flags |= MID_DELETED;
+ }
spin_unlock(&GlobalMid_Lock);
DeleteMidQEntry(mid);
@@ -168,10 +209,6 @@
*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
@@ -201,7 +238,7 @@
retries++;
if (retries >= 14 ||
(!server->noblocksnd && (retries > 2))) {
- cifs_dbg(VFS, "sends on sock %p stuck for 15 seconds\n",
+ cifs_server_dbg(VFS, "sends on sock %p stuck for 15 seconds\n",
ssocket);
return -EAGAIN;
}
@@ -215,7 +252,7 @@
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");
+ cifs_server_dbg(VFS, "tcp sent no data\n");
msleep(500);
continue;
}
@@ -275,17 +312,18 @@
__smb_send_rqst(struct TCP_Server_Info *server, int num_rqst,
struct smb_rqst *rqst)
{
- int rc = 0;
+ int rc;
struct kvec *iov;
int n_vec;
unsigned int send_length = 0;
unsigned int i, j;
+ sigset_t mask, oldmask;
size_t total_len = 0, sent, size;
struct socket *ssocket = server->ssocket;
- struct msghdr smb_msg;
- int val = 1;
+ struct msghdr smb_msg = {};
__be32 rfc1002_marker;
+ cifs_in_send_inc(server);
if (cifs_rdma_enabled(server)) {
/* return -EAGAIN when connecting or reconnecting */
rc = -EAGAIN;
@@ -293,16 +331,34 @@
rc = smbd_send(server, num_rqst, rqst);
goto smbd_done;
}
- if (ssocket == NULL)
- return -ENOTSOCK;
+ rc = -EAGAIN;
+ if (ssocket == NULL)
+ goto out;
+
+ rc = -ERESTARTSYS;
+ if (fatal_signal_pending(current)) {
+ cifs_dbg(FYI, "signal pending before send request\n");
+ goto out;
+ }
+
+ rc = 0;
/* cork the socket */
- kernel_setsockopt(ssocket, SOL_TCP, TCP_CORK,
- (char *)&val, sizeof(val));
+ tcp_sock_set_cork(ssocket->sk, true);
for (j = 0; j < num_rqst; j++)
send_length += smb_rqst_len(server, &rqst[j]);
rfc1002_marker = cpu_to_be32(send_length);
+
+ /*
+ * We should not allow signals to interrupt the network send because
+ * any partial send will cause session reconnects thus increasing
+ * latency of system calls and overload a server with unnecessary
+ * requests.
+ */
+
+ sigfillset(&mask);
+ sigprocmask(SIG_BLOCK, &mask, &oldmask);
/* Generate a rfc1002 marker for SMB2+ */
if (server->vals->header_preamble_size == 0) {
@@ -310,11 +366,10 @@
.iov_base = &rfc1002_marker,
.iov_len = 4
};
- iov_iter_kvec(&smb_msg.msg_iter, WRITE | ITER_KVEC, &hiov,
- 1, 4);
+ iov_iter_kvec(&smb_msg.msg_iter, WRITE, &hiov, 1, 4);
rc = smb_send_kvec(server, &smb_msg, &sent);
if (rc < 0)
- goto uncork;
+ goto unmask;
total_len += sent;
send_length += 4;
@@ -332,12 +387,11 @@
size += iov[i].iov_len;
}
- iov_iter_kvec(&smb_msg.msg_iter, WRITE | ITER_KVEC,
- iov, n_vec, size);
+ iov_iter_kvec(&smb_msg.msg_iter, WRITE, iov, n_vec, size);
rc = smb_send_kvec(server, &smb_msg, &sent);
if (rc < 0)
- goto uncork;
+ goto unmask;
total_len += sent;
@@ -349,7 +403,7 @@
rqst_page_get_length(&rqst[j], i, &bvec.bv_len,
&bvec.bv_offset);
- iov_iter_bvec(&smb_msg.msg_iter, WRITE | ITER_BVEC,
+ iov_iter_bvec(&smb_msg.msg_iter, WRITE,
&bvec, 1, bvec.bv_len);
rc = smb_send_kvec(server, &smb_msg, &sent);
if (rc < 0)
@@ -359,11 +413,27 @@
}
}
-uncork:
+unmask:
+ sigprocmask(SIG_SETMASK, &oldmask, NULL);
+
+ /*
+ * If signal is pending but we have already sent the whole packet to
+ * the server we need to return success status to allow a corresponding
+ * mid entry to be kept in the pending requests queue thus allowing
+ * to handle responses from the server by the client.
+ *
+ * If only part of the packet has been sent there is no need to hide
+ * interrupt because the session will be reconnected anyway, so there
+ * won't be any response from the server to handle.
+ */
+
+ if (signal_pending(current) && (total_len != send_length)) {
+ cifs_dbg(FYI, "signal is pending after attempt to send\n");
+ rc = -ERESTARTSYS;
+ }
+
/* uncork it */
- val = 0;
- kernel_setsockopt(ssocket, SOL_TCP, TCP_CORK,
- (char *)&val, sizeof(val));
+ tcp_sock_set_cork(ssocket->sk, false);
if ((total_len > 0) && (total_len != send_length)) {
cifs_dbg(FYI, "partial send (wanted=%u sent=%zu): terminating session\n",
@@ -379,11 +449,12 @@
}
smbd_done:
if (rc < 0 && rc != -EINTR)
- cifs_dbg(VFS, "Error %d sending data on socket to server\n",
+ cifs_server_dbg(VFS, "Error %d sending data on socket to server\n",
rc);
else if (rc > 0)
rc = 0;
-
+out:
+ cifs_in_send_dec(server);
return rc;
}
@@ -403,8 +474,7 @@
return -ENOMEM;
if (!server->ops->init_transform_rq) {
- cifs_dbg(VFS, "Encryption requested but transform callback "
- "is missing\n");
+ cifs_server_dbg(VFS, "Encryption requested but transform callback is missing\n");
return -EIO;
}
@@ -450,29 +520,57 @@
}
static int
-wait_for_free_credits(struct TCP_Server_Info *server, const int timeout,
- int *credits)
+wait_for_free_credits(struct TCP_Server_Info *server, const int num_credits,
+ const int timeout, const int flags,
+ unsigned int *instance)
{
- int rc;
+ long rc;
+ int *credits;
+ int optype;
+ long int t;
+
+ if (timeout < 0)
+ t = MAX_JIFFY_OFFSET;
+ else
+ t = msecs_to_jiffies(timeout);
+
+ optype = flags & CIFS_OP_MASK;
+
+ *instance = 0;
+
+ credits = server->ops->get_credits_field(server, optype);
+ /* Since an echo is already inflight, no need to wait to send another */
+ if (*credits <= 0 && optype == CIFS_ECHO_OP)
+ return -EAGAIN;
spin_lock(&server->req_lock);
- if (timeout == CIFS_ASYNC_OP) {
+ if ((flags & CIFS_TIMEOUT_MASK) == CIFS_NON_BLOCKING) {
/* oplock breaks must not be held up */
server->in_flight++;
+ if (server->in_flight > server->max_in_flight)
+ server->max_in_flight = server->in_flight;
*credits -= 1;
+ *instance = server->reconnect_instance;
spin_unlock(&server->req_lock);
return 0;
}
while (1) {
- if (*credits <= 0) {
+ if (*credits < num_credits) {
spin_unlock(&server->req_lock);
cifs_num_waiters_inc(server);
- rc = wait_event_killable(server->request_q,
- has_credits(server, credits));
+ rc = wait_event_killable_timeout(server->request_q,
+ has_credits(server, credits, num_credits), t);
cifs_num_waiters_dec(server);
- if (rc)
- return rc;
+ if (!rc) {
+ trace_smb3_credit_timeout(server->CurrentMid,
+ server->hostname, num_credits, 0);
+ cifs_server_dbg(VFS, "wait timed out after %d ms\n",
+ timeout);
+ return -ENOTSUPP;
+ }
+ if (rc == -ERESTARTSYS)
+ return -ERESTARTSYS;
spin_lock(&server->req_lock);
} else {
if (server->tcpStatus == CifsExiting) {
@@ -481,14 +579,56 @@
}
/*
+ * For normal commands, reserve the last MAX_COMPOUND
+ * credits to compound requests.
+ * Otherwise these compounds could be permanently
+ * starved for credits by single-credit requests.
+ *
+ * To prevent spinning CPU, block this thread until
+ * there are >MAX_COMPOUND credits available.
+ * But only do this is we already have a lot of
+ * credits in flight to avoid triggering this check
+ * for servers that are slow to hand out credits on
+ * new sessions.
+ */
+ if (!optype && num_credits == 1 &&
+ server->in_flight > 2 * MAX_COMPOUND &&
+ *credits <= MAX_COMPOUND) {
+ spin_unlock(&server->req_lock);
+ cifs_num_waiters_inc(server);
+ rc = wait_event_killable_timeout(
+ server->request_q,
+ has_credits(server, credits,
+ MAX_COMPOUND + 1),
+ t);
+ cifs_num_waiters_dec(server);
+ if (!rc) {
+ trace_smb3_credit_timeout(
+ server->CurrentMid,
+ server->hostname, num_credits,
+ 0);
+ cifs_server_dbg(VFS, "wait timed out after %d ms\n",
+ timeout);
+ return -ENOTSUPP;
+ }
+ if (rc == -ERESTARTSYS)
+ return -ERESTARTSYS;
+ spin_lock(&server->req_lock);
+ continue;
+ }
+
+ /*
* 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++;
+ if ((flags & CIFS_TIMEOUT_MASK) != CIFS_BLOCKING_OP) {
+ *credits -= num_credits;
+ server->in_flight += num_credits;
+ if (server->in_flight > server->max_in_flight)
+ server->max_in_flight = server->in_flight;
+ *instance = server->reconnect_instance;
}
spin_unlock(&server->req_lock);
break;
@@ -498,24 +638,57 @@
}
static int
-wait_for_free_request(struct TCP_Server_Info *server, const int timeout,
- const int optype)
+wait_for_free_request(struct TCP_Server_Info *server, const int flags,
+ unsigned int *instance)
{
- int *val;
+ return wait_for_free_credits(server, 1, -1, flags,
+ instance);
+}
- val = server->ops->get_credits_field(server, optype);
- /* Since an echo is already inflight, no need to wait to send another */
- if (*val <= 0 && optype == CIFS_ECHO_OP)
- return -EAGAIN;
- return wait_for_free_credits(server, timeout, val);
+static int
+wait_for_compound_request(struct TCP_Server_Info *server, int num,
+ const int flags, unsigned int *instance)
+{
+ int *credits;
+
+ credits = server->ops->get_credits_field(server, flags & CIFS_OP_MASK);
+
+ spin_lock(&server->req_lock);
+ if (*credits < num) {
+ /*
+ * If the server is tight on resources or just gives us less
+ * credits for other reasons (e.g. requests are coming out of
+ * order and the server delays granting more credits until it
+ * processes a missing mid) and we exhausted most available
+ * credits there may be situations when we try to send
+ * a compound request but we don't have enough credits. At this
+ * point the client needs to decide if it should wait for
+ * additional credits or fail the request. If at least one
+ * request is in flight there is a high probability that the
+ * server will return enough credits to satisfy this compound
+ * request.
+ *
+ * Return immediately if no requests in flight since we will be
+ * stuck on waiting for credits.
+ */
+ if (server->in_flight == 0) {
+ spin_unlock(&server->req_lock);
+ return -ENOTSUPP;
+ }
+ }
+ spin_unlock(&server->req_lock);
+
+ return wait_for_free_credits(server, num, 60000, flags,
+ instance);
}
int
cifs_wait_mtu_credits(struct TCP_Server_Info *server, unsigned int size,
- unsigned int *num, unsigned int *credits)
+ unsigned int *num, struct cifs_credits *credits)
{
*num = size;
- *credits = 0;
+ credits->value = 0;
+ credits->instance = server->reconnect_instance;
return 0;
}
@@ -602,27 +775,43 @@
int
cifs_call_async(struct TCP_Server_Info *server, struct smb_rqst *rqst,
mid_receive_t *receive, mid_callback_t *callback,
- mid_handle_t *handle, void *cbdata, const int flags)
+ mid_handle_t *handle, void *cbdata, const int flags,
+ const struct cifs_credits *exist_credits)
{
- int rc, timeout, optype;
+ int rc;
struct mid_q_entry *mid;
- unsigned int credits = 0;
+ struct cifs_credits credits = { .value = 0, .instance = 0 };
+ unsigned int instance;
+ int optype;
- timeout = flags & CIFS_TIMEOUT_MASK;
optype = flags & CIFS_OP_MASK;
if ((flags & CIFS_HAS_CREDITS) == 0) {
- rc = wait_for_free_request(server, timeout, optype);
+ rc = wait_for_free_request(server, flags, &instance);
if (rc)
return rc;
- credits = 1;
- }
+ credits.value = 1;
+ credits.instance = instance;
+ } else
+ instance = exist_credits->instance;
mutex_lock(&server->srv_mutex);
+
+ /*
+ * We can't use credits obtained from the previous session to send this
+ * request. Check if there were reconnects after we obtained credits and
+ * return -EAGAIN in such cases to let callers handle it.
+ */
+ if (instance != server->reconnect_instance) {
+ mutex_unlock(&server->srv_mutex);
+ add_credits_and_wake_if(server, &credits, optype);
+ return -EAGAIN;
+ }
+
mid = server->ops->setup_async_request(server, rqst);
if (IS_ERR(mid)) {
mutex_unlock(&server->srv_mutex);
- add_credits_and_wake_if(server, credits, optype);
+ add_credits_and_wake_if(server, &credits, optype);
return PTR_ERR(mid);
}
@@ -642,9 +831,7 @@
* I/O response may come back and free the mid entry on another thread.
*/
cifs_save_when_sent(mid);
- cifs_in_send_inc(server);
rc = smb_send_rqst(server, 1, rqst, flags);
- cifs_in_send_dec(server);
if (rc < 0) {
revert_current_mid(server, mid->credits);
@@ -657,7 +844,7 @@
if (rc == 0)
return 0;
- add_credits_and_wake_if(server, credits, optype);
+ add_credits_and_wake_if(server, &credits, optype);
return rc;
}
@@ -681,7 +868,7 @@
iov[0].iov_base = in_buf;
iov[0].iov_len = get_rfc1002_length(in_buf) + 4;
- flags |= CIFS_NO_RESP;
+ flags |= CIFS_NO_RSP_BUF;
rc = SendReceive2(xid, ses, iov, 1, &resp_buf_type, flags, &rsp_iov);
cifs_dbg(NOISY, "SendRcvNoRsp flags %d rc %d\n", flags, rc);
@@ -711,8 +898,11 @@
rc = -EHOSTDOWN;
break;
default:
- list_del_init(&mid->qhead);
- cifs_dbg(VFS, "%s: invalid mid state mid=%llu state=%d\n",
+ if (!(mid->mid_flags & MID_DELETED)) {
+ list_del_init(&mid->qhead);
+ mid->mid_flags |= MID_DELETED;
+ }
+ cifs_server_dbg(VFS, "%s: invalid mid state mid=%llu state=%d\n",
__func__, mid->mid, mid->mid_state);
rc = -EIO;
}
@@ -753,16 +943,17 @@
rc = cifs_verify_signature(&rqst, server,
mid->sequence_number);
if (rc)
- cifs_dbg(VFS, "SMB signature verification returned error = %d\n",
+ cifs_server_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);
+ return map_and_check_smb_error(mid, log_error);
}
struct mid_q_entry *
-cifs_setup_request(struct cifs_ses *ses, struct smb_rqst *rqst)
+cifs_setup_request(struct cifs_ses *ses, struct TCP_Server_Info *ignored,
+ struct smb_rqst *rqst)
{
int rc;
struct smb_hdr *hdr = (struct smb_hdr *)rqst->rq_iov[0].iov_base;
@@ -784,61 +975,101 @@
}
static void
-cifs_noop_callback(struct mid_q_entry *mid)
+cifs_compound_callback(struct mid_q_entry *mid)
{
+ struct TCP_Server_Info *server = mid->server;
+ struct cifs_credits credits;
+
+ credits.value = server->ops->get_credits(mid);
+ credits.instance = server->reconnect_instance;
+
+ add_credits(server, &credits, mid->optype);
+}
+
+static void
+cifs_compound_last_callback(struct mid_q_entry *mid)
+{
+ cifs_compound_callback(mid);
+ cifs_wake_up_task(mid);
+}
+
+static void
+cifs_cancelled_callback(struct mid_q_entry *mid)
+{
+ cifs_compound_callback(mid);
+ DeleteMidQEntry(mid);
+}
+
+/*
+ * Return a channel (master if none) of @ses that can be used to send
+ * regular requests.
+ *
+ * If we are currently binding a new channel (negprot/sess.setup),
+ * return the new incomplete channel.
+ */
+struct TCP_Server_Info *cifs_pick_channel(struct cifs_ses *ses)
+{
+ uint index = 0;
+
+ if (!ses)
+ return NULL;
+
+ if (!ses->binding) {
+ /* round robin */
+ if (ses->chan_count > 1) {
+ index = (uint)atomic_inc_return(&ses->chan_seq);
+ index %= ses->chan_count;
+ }
+ return ses->chans[index].server;
+ } else {
+ return cifs_ses_server(ses);
+ }
}
int
compound_send_recv(const unsigned int xid, struct cifs_ses *ses,
+ struct TCP_Server_Info *server,
const int flags, const int num_rqst, struct smb_rqst *rqst,
int *resp_buf_type, struct kvec *resp_iov)
{
- int i, j, rc = 0;
- int timeout, optype;
+ int i, j, optype, rc = 0;
struct mid_q_entry *midQ[MAX_COMPOUND];
bool cancelled_mid[MAX_COMPOUND] = {false};
- unsigned int credits[MAX_COMPOUND] = {0};
+ struct cifs_credits credits[MAX_COMPOUND] = {
+ { .value = 0, .instance = 0 }
+ };
+ unsigned int instance;
char *buf;
- timeout = flags & CIFS_TIMEOUT_MASK;
optype = flags & CIFS_OP_MASK;
for (i = 0; i < num_rqst; i++)
resp_buf_type[i] = CIFS_NO_BUFFER; /* no response buf yet */
- if ((ses == NULL) || (ses->server == NULL)) {
+ if (!ses || !ses->server || !server) {
cifs_dbg(VFS, "Null session\n");
return -EIO;
}
- if (ses->server->tcpStatus == CifsExiting)
+ if (server->tcpStatus == CifsExiting)
return -ENOENT;
/*
- * Ensure we obtain 1 credit per request in the compound chain.
- * It can be optimized further by waiting for all the credits
- * at once but this can wait long enough if we don't have enough
- * credits due to some heavy operations in progress or the server
- * not granting us much, so a fallback to the current approach is
- * needed anyway.
+ * Wait for all the requests to become available.
+ * This approach still leaves the possibility to be stuck waiting for
+ * credits if the server doesn't grant credits to the outstanding
+ * requests and if the client is completely idle, not generating any
+ * other requests.
+ * This can be handled by the eventual session reconnect.
*/
+ rc = wait_for_compound_request(server, num_rqst, flags,
+ &instance);
+ if (rc)
+ return rc;
+
for (i = 0; i < num_rqst; i++) {
- rc = wait_for_free_request(ses->server, timeout, optype);
- if (rc) {
- /*
- * We haven't sent an SMB packet to the server yet but
- * we already obtained credits for i requests in the
- * compound chain - need to return those credits back
- * for future use. Note that we need to call add_credits
- * multiple times to match the way we obtained credits
- * in the first place and to account for in flight
- * requests correctly.
- */
- for (j = 0; j < i; j++)
- add_credits(ses->server, 1, optype);
- return rc;
- }
- credits[i] = 1;
+ credits[i].value = 1;
+ credits[i].instance = instance;
}
/*
@@ -847,86 +1078,114 @@
* of smb data.
*/
- mutex_lock(&ses->server->srv_mutex);
+ mutex_lock(&server->srv_mutex);
+
+ /*
+ * All the parts of the compound chain belong obtained credits from the
+ * same session. We can not use credits obtained from the previous
+ * session to send this request. Check if there were reconnects after
+ * we obtained credits and return -EAGAIN in such cases to let callers
+ * handle it.
+ */
+ if (instance != server->reconnect_instance) {
+ mutex_unlock(&server->srv_mutex);
+ for (j = 0; j < num_rqst; j++)
+ add_credits(server, &credits[j], optype);
+ return -EAGAIN;
+ }
for (i = 0; i < num_rqst; i++) {
- midQ[i] = ses->server->ops->setup_request(ses, &rqst[i]);
+ midQ[i] = server->ops->setup_request(ses, server, &rqst[i]);
if (IS_ERR(midQ[i])) {
- revert_current_mid(ses->server, i);
+ revert_current_mid(server, i);
for (j = 0; j < i; j++)
cifs_delete_mid(midQ[j]);
- mutex_unlock(&ses->server->srv_mutex);
+ mutex_unlock(&server->srv_mutex);
/* Update # of requests on wire to server */
for (j = 0; j < num_rqst; j++)
- add_credits(ses->server, credits[j], optype);
+ add_credits(server, &credits[j], optype);
return PTR_ERR(midQ[i]);
}
midQ[i]->mid_state = MID_REQUEST_SUBMITTED;
+ midQ[i]->optype = optype;
/*
- * We don't invoke the callback compounds unless it is the last
- * request.
+ * Invoke callback for every part of the compound chain
+ * to calculate credits properly. Wake up this thread only when
+ * the last element is received.
*/
if (i < num_rqst - 1)
- midQ[i]->callback = cifs_noop_callback;
+ midQ[i]->callback = cifs_compound_callback;
+ else
+ midQ[i]->callback = cifs_compound_last_callback;
}
- cifs_in_send_inc(ses->server);
- rc = smb_send_rqst(ses->server, num_rqst, rqst, flags);
- cifs_in_send_dec(ses->server);
+ rc = smb_send_rqst(server, num_rqst, rqst, flags);
for (i = 0; i < num_rqst; i++)
cifs_save_when_sent(midQ[i]);
if (rc < 0) {
- revert_current_mid(ses->server, num_rqst);
- ses->server->sequence_number -= 2;
+ revert_current_mid(server, num_rqst);
+ server->sequence_number -= 2;
}
- mutex_unlock(&ses->server->srv_mutex);
+ mutex_unlock(&server->srv_mutex);
- if (rc < 0)
+ /*
+ * If sending failed for some reason or it is an oplock break that we
+ * will not receive a response to - return credits back
+ */
+ if (rc < 0 || (flags & CIFS_NO_SRV_RSP)) {
+ for (i = 0; i < num_rqst; i++)
+ add_credits(server, &credits[i], optype);
goto out;
+ }
+
+ /*
+ * At this point the request is passed to the network stack - we assume
+ * that any credits taken from the server structure on the client have
+ * been spent and we can't return them back. Once we receive responses
+ * we will collect credits granted by the server in the mid callbacks
+ * and add those credits to the server structure.
+ */
/*
* Compounding is never used during session establish.
*/
if ((ses->status == CifsNew) || (optype & CIFS_NEG_OP)) {
- mutex_lock(&ses->server->srv_mutex);
+ mutex_lock(&server->srv_mutex);
smb311_update_preauth_hash(ses, rqst[0].rq_iov,
rqst[0].rq_nvec);
- mutex_unlock(&ses->server->srv_mutex);
+ mutex_unlock(&server->srv_mutex);
}
- if (timeout == CIFS_ASYNC_OP)
- goto out;
-
for (i = 0; i < num_rqst; i++) {
- rc = wait_for_response(ses->server, midQ[i]);
- if (rc != 0) {
- cifs_dbg(FYI, "Cancelling wait for mid %llu\n",
- midQ[i]->mid);
- send_cancel(ses->server, &rqst[i], midQ[i]);
+ rc = wait_for_response(server, midQ[i]);
+ if (rc != 0)
+ break;
+ }
+ if (rc != 0) {
+ for (; i < num_rqst; i++) {
+ cifs_server_dbg(FYI, "Cancelling wait for mid %llu cmd: %d\n",
+ midQ[i]->mid, le16_to_cpu(midQ[i]->command));
+ send_cancel(server, &rqst[i], midQ[i]);
spin_lock(&GlobalMid_Lock);
+ midQ[i]->mid_flags |= MID_WAIT_CANCELLED;
if (midQ[i]->mid_state == MID_REQUEST_SUBMITTED) {
- midQ[i]->mid_flags |= MID_WAIT_CANCELLED;
- midQ[i]->callback = DeleteMidQEntry;
+ midQ[i]->callback = cifs_cancelled_callback;
cancelled_mid[i] = true;
+ credits[i].value = 0;
}
spin_unlock(&GlobalMid_Lock);
}
}
- for (i = 0; i < num_rqst; i++)
- if (!cancelled_mid[i] && midQ[i]->resp_buf
- && (midQ[i]->mid_state == MID_RESPONSE_RECEIVED))
- credits[i] = ses->server->ops->get_credits(midQ[i]);
-
for (i = 0; i < num_rqst; i++) {
if (rc < 0)
goto out;
- rc = cifs_sync_mid_result(midQ[i], ses->server);
+ rc = cifs_sync_mid_result(midQ[i], server);
if (rc != 0) {
/* mark this mid as cancelled to not free it below */
cancelled_mid[i] = true;
@@ -943,18 +1202,18 @@
buf = (char *)midQ[i]->resp_buf;
resp_iov[i].iov_base = buf;
resp_iov[i].iov_len = midQ[i]->resp_buf_size +
- ses->server->vals->header_preamble_size;
+ server->vals->header_preamble_size;
if (midQ[i]->large_buf)
resp_buf_type[i] = CIFS_LARGE_BUFFER;
else
resp_buf_type[i] = CIFS_SMALL_BUFFER;
- rc = ses->server->ops->check_receive(midQ[i], ses->server,
+ rc = server->ops->check_receive(midQ[i], server,
flags & CIFS_LOG_ERROR);
/* mark it so buf will not be freed by cifs_delete_mid */
- if ((flags & CIFS_NO_RESP) == 0)
+ if ((flags & CIFS_NO_RSP_BUF) == 0)
midQ[i]->resp_buf = NULL;
}
@@ -967,9 +1226,9 @@
.iov_base = resp_iov[0].iov_base,
.iov_len = resp_iov[0].iov_len
};
- mutex_lock(&ses->server->srv_mutex);
+ mutex_lock(&server->srv_mutex);
smb311_update_preauth_hash(ses, &iov, 1);
- mutex_unlock(&ses->server->srv_mutex);
+ mutex_unlock(&server->srv_mutex);
}
out:
@@ -982,7 +1241,6 @@
for (i = 0; i < num_rqst; i++) {
if (!cancelled_mid[i])
cifs_delete_mid(midQ[i]);
- add_credits(ses->server, credits[i], optype);
}
return rc;
@@ -990,11 +1248,12 @@
int
cifs_send_recv(const unsigned int xid, struct cifs_ses *ses,
+ struct TCP_Server_Info *server,
struct smb_rqst *rqst, int *resp_buf_type, const int flags,
struct kvec *resp_iov)
{
- return compound_send_recv(xid, ses, flags, 1, rqst, resp_buf_type,
- resp_iov);
+ return compound_send_recv(xid, ses, server, flags, 1,
+ rqst, resp_buf_type, resp_iov);
}
int
@@ -1029,7 +1288,8 @@
rqst.rq_iov = new_iov;
rqst.rq_nvec = n_vec + 1;
- rc = cifs_send_recv(xid, ses, &rqst, resp_buf_type, flags, resp_iov);
+ rc = cifs_send_recv(xid, ses, ses->server,
+ &rqst, resp_buf_type, flags, resp_iov);
if (n_vec + 1 > CIFS_MAX_IOV_SIZE)
kfree(new_iov);
return rc;
@@ -1038,24 +1298,27 @@
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 *pbytes_returned, const int flags)
{
int rc = 0;
struct mid_q_entry *midQ;
unsigned int len = be32_to_cpu(in_buf->smb_buf_length);
struct kvec iov = { .iov_base = in_buf, .iov_len = len };
struct smb_rqst rqst = { .rq_iov = &iov, .rq_nvec = 1 };
+ struct cifs_credits credits = { .value = 1, .instance = 0 };
+ struct TCP_Server_Info *server;
if (ses == NULL) {
cifs_dbg(VFS, "Null smb session\n");
return -EIO;
}
- if (ses->server == NULL) {
+ server = ses->server;
+ if (server == NULL) {
cifs_dbg(VFS, "Null tcp session\n");
return -EIO;
}
- if (ses->server->tcpStatus == CifsExiting)
+ if (server->tcpStatus == CifsExiting)
return -ENOENT;
/* Ensure that we do not send more than 50 overlapping requests
@@ -1063,12 +1326,12 @@
use ses->maxReq */
if (len > CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4) {
- cifs_dbg(VFS, "Illegal length, greater than maximum frame, %d\n",
- len);
+ cifs_server_dbg(VFS, "Invalid length, greater than maximum frame, %d\n",
+ len);
return -EIO;
}
- rc = wait_for_free_request(ses->server, timeout, 0);
+ rc = wait_for_free_request(server, flags, &credits.instance);
if (rc)
return rc;
@@ -1076,73 +1339,68 @@
and avoid races inside tcp sendmsg code that could cause corruption
of smb data */
- mutex_lock(&ses->server->srv_mutex);
+ mutex_lock(&server->srv_mutex);
rc = allocate_mid(ses, in_buf, &midQ);
if (rc) {
- mutex_unlock(&ses->server->srv_mutex);
+ mutex_unlock(&server->srv_mutex);
/* Update # of requests on wire to server */
- add_credits(ses->server, 1, 0);
+ add_credits(server, &credits, 0);
return rc;
}
- rc = cifs_sign_smb(in_buf, ses->server, &midQ->sequence_number);
+ rc = cifs_sign_smb(in_buf, server, &midQ->sequence_number);
if (rc) {
- mutex_unlock(&ses->server->srv_mutex);
+ mutex_unlock(&server->srv_mutex);
goto out;
}
midQ->mid_state = MID_REQUEST_SUBMITTED;
- cifs_in_send_inc(ses->server);
- rc = smb_send(ses->server, in_buf, len);
- cifs_in_send_dec(ses->server);
+ rc = smb_send(server, in_buf, len);
cifs_save_when_sent(midQ);
if (rc < 0)
- ses->server->sequence_number -= 2;
+ server->sequence_number -= 2;
- mutex_unlock(&ses->server->srv_mutex);
+ mutex_unlock(&server->srv_mutex);
if (rc < 0)
goto out;
- if (timeout == CIFS_ASYNC_OP)
- goto out;
-
- rc = wait_for_response(ses->server, midQ);
+ rc = wait_for_response(server, midQ);
if (rc != 0) {
- send_cancel(ses->server, &rqst, midQ);
+ send_cancel(server, &rqst, 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);
+ add_credits(server, &credits, 0);
return rc;
}
spin_unlock(&GlobalMid_Lock);
}
- rc = cifs_sync_mid_result(midQ, ses->server);
+ rc = cifs_sync_mid_result(midQ, server);
if (rc != 0) {
- add_credits(ses->server, 1, 0);
+ add_credits(server, &credits, 0);
return rc;
}
if (!midQ->resp_buf || !out_buf ||
midQ->mid_state != MID_RESPONSE_RECEIVED) {
rc = -EIO;
- cifs_dbg(VFS, "Bad MID state?\n");
+ cifs_server_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);
+ rc = cifs_check_receive(midQ, server, 0);
out:
cifs_delete_mid(midQ);
- add_credits(ses->server, 1, 0);
+ add_credits(server, &credits, 0);
return rc;
}
@@ -1184,19 +1442,22 @@
unsigned int len = be32_to_cpu(in_buf->smb_buf_length);
struct kvec iov = { .iov_base = in_buf, .iov_len = len };
struct smb_rqst rqst = { .rq_iov = &iov, .rq_nvec = 1 };
+ unsigned int instance;
+ struct TCP_Server_Info *server;
if (tcon == NULL || tcon->ses == NULL) {
cifs_dbg(VFS, "Null smb session\n");
return -EIO;
}
ses = tcon->ses;
+ server = ses->server;
- if (ses->server == NULL) {
+ if (server == NULL) {
cifs_dbg(VFS, "Null tcp session\n");
return -EIO;
}
- if (ses->server->tcpStatus == CifsExiting)
+ if (server->tcpStatus == CifsExiting)
return -ENOENT;
/* Ensure that we do not send more than 50 overlapping requests
@@ -1204,12 +1465,12 @@
use ses->maxReq */
if (len > CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4) {
- cifs_dbg(VFS, "Illegal length, greater than maximum frame, %d\n",
- len);
+ cifs_tcon_dbg(VFS, "Invalid length, greater than maximum frame, %d\n",
+ len);
return -EIO;
}
- rc = wait_for_free_request(ses->server, CIFS_BLOCKING_OP, 0);
+ rc = wait_for_free_request(server, CIFS_BLOCKING_OP, &instance);
if (rc)
return rc;
@@ -1217,31 +1478,29 @@
and avoid races inside tcp sendmsg code that could cause corruption
of smb data */
- mutex_lock(&ses->server->srv_mutex);
+ mutex_lock(&server->srv_mutex);
rc = allocate_mid(ses, in_buf, &midQ);
if (rc) {
- mutex_unlock(&ses->server->srv_mutex);
+ mutex_unlock(&server->srv_mutex);
return rc;
}
- rc = cifs_sign_smb(in_buf, ses->server, &midQ->sequence_number);
+ rc = cifs_sign_smb(in_buf, server, &midQ->sequence_number);
if (rc) {
cifs_delete_mid(midQ);
- mutex_unlock(&ses->server->srv_mutex);
+ mutex_unlock(&server->srv_mutex);
return rc;
}
midQ->mid_state = MID_REQUEST_SUBMITTED;
- cifs_in_send_inc(ses->server);
- rc = smb_send(ses->server, in_buf, len);
- cifs_in_send_dec(ses->server);
+ rc = smb_send(server, in_buf, len);
cifs_save_when_sent(midQ);
if (rc < 0)
- ses->server->sequence_number -= 2;
+ server->sequence_number -= 2;
- mutex_unlock(&ses->server->srv_mutex);
+ mutex_unlock(&server->srv_mutex);
if (rc < 0) {
cifs_delete_mid(midQ);
@@ -1249,21 +1508,21 @@
}
/* Wait for a reply - allow signals to interrupt. */
- rc = wait_event_interruptible(ses->server->response_q,
+ rc = wait_event_interruptible(server->response_q,
(!(midQ->mid_state == MID_REQUEST_SUBMITTED)) ||
- ((ses->server->tcpStatus != CifsGood) &&
- (ses->server->tcpStatus != CifsNew)));
+ ((server->tcpStatus != CifsGood) &&
+ (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))) {
+ ((server->tcpStatus == CifsGood) ||
+ (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, &rqst, midQ);
+ rc = send_cancel(server, &rqst, midQ);
if (rc) {
cifs_delete_mid(midQ);
return rc;
@@ -1282,9 +1541,9 @@
}
}
- rc = wait_for_response(ses->server, midQ);
+ rc = wait_for_response(server, midQ);
if (rc) {
- send_cancel(ses->server, &rqst, midQ);
+ send_cancel(server, &rqst, midQ);
spin_lock(&GlobalMid_Lock);
if (midQ->mid_state == MID_REQUEST_SUBMITTED) {
/* no longer considered to be "in-flight" */
@@ -1299,20 +1558,20 @@
rstart = 1;
}
- rc = cifs_sync_mid_result(midQ, ses->server);
+ rc = cifs_sync_mid_result(midQ, 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");
+ cifs_tcon_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);
+ rc = cifs_check_receive(midQ, server, 0);
out:
cifs_delete_mid(midQ);
if (rstart && rc == -EACCES)
--
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