CIFS: Prepare credits code for a slot reservation

that is essential for CIFS/SMB/SMB2 oplock breaks and SMB2 echos.

Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Pavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: Steve French <sfrench@us.ibm.com>
This commit is contained in:
Pavel Shilovsky 2012-03-15 13:22:27 +03:00 committed by Steve French
parent 5bc594982f
commit bc205ed19b
2 changed files with 26 additions and 10 deletions

View File

@ -315,12 +315,22 @@ in_flight(struct TCP_Server_Info *server)
return num;
}
static inline int*
get_credits_field(struct TCP_Server_Info *server)
{
/*
* This will change to switch statement when we reserve slots for echos
* and oplock breaks.
*/
return &server->credits;
}
static inline bool
has_credits(struct TCP_Server_Info *server)
has_credits(struct TCP_Server_Info *server, int *credits)
{
int num;
spin_lock(&server->req_lock);
num = server->credits;
num = *credits;
spin_unlock(&server->req_lock);
return num > 0;
}

View File

@ -255,26 +255,26 @@ smb_send(struct TCP_Server_Info *server, struct smb_hdr *smb_buffer,
}
static int
wait_for_free_request(struct TCP_Server_Info *server, const int long_op)
wait_for_free_credits(struct TCP_Server_Info *server, const int optype,
int *credits)
{
int rc;
spin_lock(&server->req_lock);
if (long_op == CIFS_ASYNC_OP) {
if (optype == CIFS_ASYNC_OP) {
/* oplock breaks must not be held up */
server->in_flight++;
server->credits--;
*credits -= 1;
spin_unlock(&server->req_lock);
return 0;
}
while (1) {
if (server->credits <= 0) {
if (*credits <= 0) {
spin_unlock(&server->req_lock);
cifs_num_waiters_inc(server);
rc = wait_event_killable(server->request_q,
has_credits(server));
has_credits(server, credits));
cifs_num_waiters_dec(server);
if (rc)
return rc;
@ -291,8 +291,8 @@ wait_for_free_request(struct TCP_Server_Info *server, const int long_op)
*/
/* update # of requests on the wire to server */
if (long_op != CIFS_BLOCKING_OP) {
server->credits--;
if (optype != CIFS_BLOCKING_OP) {
*credits -= 1;
server->in_flight++;
}
spin_unlock(&server->req_lock);
@ -302,6 +302,12 @@ wait_for_free_request(struct TCP_Server_Info *server, const int long_op)
return 0;
}
static int
wait_for_free_request(struct TCP_Server_Info *server, const int optype)
{
return wait_for_free_credits(server, optype, get_credits_field(server));
}
static int allocate_mid(struct cifs_ses *ses, struct smb_hdr *in_buf,
struct mid_q_entry **ppmidQ)
{