diff options
| author | Ronnie Sahlberg <lsahlber@redhat.com> | 2019-03-08 03:58:22 +0100 |
|---|---|---|
| committer | Steve French <stfrench@microsoft.com> | 2019-03-15 01:32:35 +0100 |
| commit | 2b53b929faedacc6531bbb4315585cb7c14a252d (patch) | |
| tree | fb8824c64da425a206749e1ae8a054177a26e4f4 /fs | |
| parent | cifs: prevent starvation in wait_for_free_credits for multi-credit requests (diff) | |
| download | linux-2b53b929faedacc6531bbb4315585cb7c14a252d.tar.xz linux-2b53b929faedacc6531bbb4315585cb7c14a252d.zip | |
cifs: add a timeout argument to wait_for_free_credits
A negative timeout is the same as the current behaviour, i.e. no timeout.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/cifs/transport.c | 40 |
1 files changed, 30 insertions, 10 deletions
diff --git a/fs/cifs/transport.c b/fs/cifs/transport.c index 9e08ce722dbb..b3d04018195c 100644 --- a/fs/cifs/transport.c +++ b/fs/cifs/transport.c @@ -487,11 +487,18 @@ smb_send(struct TCP_Server_Info *server, struct smb_hdr *smb_buffer, static int wait_for_free_credits(struct TCP_Server_Info *server, const int num_credits, - const int flags, unsigned int *instance) + const int timeout, const int flags, + unsigned int *instance) { int 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; @@ -516,11 +523,16 @@ wait_for_free_credits(struct TCP_Server_Info *server, const int num_credits, 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, num_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) { + cifs_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) { @@ -546,12 +558,19 @@ wait_for_free_credits(struct TCP_Server_Info *server, const int num_credits, *credits <= MAX_COMPOUND) { spin_unlock(&server->req_lock); cifs_num_waiters_inc(server); - rc = wait_event_killable(server->request_q, + rc = wait_event_killable_timeout( + server->request_q, has_credits(server, credits, - MAX_COMPOUND + 1)); + MAX_COMPOUND + 1), + t); cifs_num_waiters_dec(server); - if (rc) - return rc; + if (!rc) { + cifs_dbg(VFS, "wait timed out after %d ms\n", + timeout); + return -ENOTSUPP; + } + if (rc == -ERESTARTSYS) + return -ERESTARTSYS; spin_lock(&server->req_lock); continue; } @@ -578,7 +597,8 @@ static int wait_for_free_request(struct TCP_Server_Info *server, const int flags, unsigned int *instance) { - return wait_for_free_credits(server, 1, flags, instance); + return wait_for_free_credits(server, 1, -1, flags, + instance); } int |