CIFS: Add SMB2 credits support
For SMB2 protocol we can add more than one credit for one received
request: it depends on CreditRequest field in SMB2 response header.
Also we divide all requests by type: echoes, oplocks and others.
Each type uses its own slot pull.
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Pavel Shilovsky <pshilovsky@samba.org>
Signed-off-by: Steve French <smfrench@gmail.com>
diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
index 3575f0f..480b638 100644
--- a/fs/cifs/cifsglob.h
+++ b/fs/cifs/cifsglob.h
@@ -343,6 +343,11 @@
char server_GUID[16];
__u16 sec_mode;
bool session_estab; /* mark when very first sess is established */
+#ifdef CONFIG_CIFS_SMB2
+ int echo_credits; /* echo reserved slots */
+ int oplock_credits; /* oplock break reserved slots */
+ bool echoes:1; /* enable echoes */
+#endif
u16 dialect; /* dialect index that server chose */
enum securityEnum secType;
bool oplocks:1; /* enable oplocks */
diff --git a/fs/cifs/cifsproto.h b/fs/cifs/cifsproto.h
index 88967d0..3b4d41f 100644
--- a/fs/cifs/cifsproto.h
+++ b/fs/cifs/cifsproto.h
@@ -91,6 +91,7 @@
struct smb_hdr *in_buf ,
struct smb_hdr *out_buf,
int *bytes_returned);
+extern int cifs_reconnect(struct TCP_Server_Info *server);
extern int checkSMB(char *buf, unsigned int length);
extern bool is_valid_oplock_break(char *, struct TCP_Server_Info *);
extern bool backup_cred(struct cifs_sb_info *);
diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index cfb7e77..a619722 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -297,7 +297,7 @@
* reconnect tcp session
* wake up waiters on reconnection? - (not needed currently)
*/
-static int
+int
cifs_reconnect(struct TCP_Server_Info *server)
{
int rc = 0;
diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c
index 09530f4..67a0598 100644
--- a/fs/cifs/smb2ops.c
+++ b/fs/cifs/smb2ops.c
@@ -20,6 +20,81 @@
#include "cifsglob.h"
#include "smb2pdu.h"
#include "smb2proto.h"
+#include "cifsproto.h"
+#include "cifs_debug.h"
+
+static int
+change_conf(struct TCP_Server_Info *server)
+{
+ server->credits += server->echo_credits + server->oplock_credits;
+ server->oplock_credits = server->echo_credits = 0;
+ switch (server->credits) {
+ case 0:
+ return -1;
+ case 1:
+ server->echoes = false;
+ server->oplocks = false;
+ cERROR(1, "disabling echoes and oplocks");
+ break;
+ case 2:
+ server->echoes = true;
+ server->oplocks = false;
+ server->echo_credits = 1;
+ cFYI(1, "disabling oplocks");
+ break;
+ default:
+ server->echoes = true;
+ server->oplocks = true;
+ server->echo_credits = 1;
+ server->oplock_credits = 1;
+ }
+ server->credits -= server->echo_credits + server->oplock_credits;
+ return 0;
+}
+
+static void
+smb2_add_credits(struct TCP_Server_Info *server, const unsigned int add,
+ const int optype)
+{
+ int *val, rc = 0;
+ spin_lock(&server->req_lock);
+ val = server->ops->get_credits_field(server, optype);
+ *val += add;
+ server->in_flight--;
+ if (server->in_flight == 0)
+ rc = change_conf(server);
+ spin_unlock(&server->req_lock);
+ wake_up(&server->request_q);
+ if (rc)
+ cifs_reconnect(server);
+}
+
+static void
+smb2_set_credits(struct TCP_Server_Info *server, const int val)
+{
+ spin_lock(&server->req_lock);
+ server->credits = val;
+ spin_unlock(&server->req_lock);
+}
+
+static int *
+smb2_get_credits_field(struct TCP_Server_Info *server, const int optype)
+{
+ switch (optype) {
+ case CIFS_ECHO_OP:
+ return &server->echo_credits;
+ case CIFS_OBREAK_OP:
+ return &server->oplock_credits;
+ default:
+ return &server->credits;
+ }
+}
+
+static unsigned int
+smb2_get_credits(struct mid_q_entry *mid)
+{
+ return le16_to_cpu(((struct smb2_hdr *)mid->resp_buf)->CreditRequest);
+}
static __u64
smb2_get_next_mid(struct TCP_Server_Info *server)
@@ -35,6 +110,10 @@
struct smb_version_operations smb21_operations = {
.setup_request = smb2_setup_request,
.check_receive = smb2_check_receive,
+ .add_credits = smb2_add_credits,
+ .set_credits = smb2_set_credits,
+ .get_credits_field = smb2_get_credits_field,
+ .get_credits = smb2_get_credits,
.get_next_mid = smb2_get_next_mid,
};