struct list_head list;
struct sclp_req sclp_req;
int retry_count;
- struct timer_list retry_timer;
};
/* VT220 SCCB */
static int sclp_vt220_flush_later;
static void sclp_vt220_receiver_fn(struct evbuf_header *evbuf);
-static void __sclp_vt220_emit(struct sclp_vt220_request *request);
+static int __sclp_vt220_emit(struct sclp_vt220_request *request);
static void sclp_vt220_emit_current(void);
/* Registration structure for our interest in SCLP event buffers */
sclp_vt220_process_queue(struct sclp_vt220_request *request)
{
unsigned long flags;
- struct sclp_vt220_request *next;
void *page;
- /* Put buffer back to list of empty buffers */
- page = request->sclp_req.sccb;
- spin_lock_irqsave(&sclp_vt220_lock, flags);
- /* Move request from outqueue to empty queue */
- list_del(&request->list);
- sclp_vt220_outqueue_count--;
- list_add_tail((struct list_head *) page, &sclp_vt220_empty);
- /* Check if there is a pending buffer on the out queue. */
- next = NULL;
- if (!list_empty(&sclp_vt220_outqueue))
- next = list_entry(sclp_vt220_outqueue.next,
- struct sclp_vt220_request, list);
- spin_unlock_irqrestore(&sclp_vt220_lock, flags);
- if (next != NULL)
- __sclp_vt220_emit(next);
- else if (sclp_vt220_flush_later)
+ do {
+ /* Put buffer back to list of empty buffers */
+ page = request->sclp_req.sccb;
+ spin_lock_irqsave(&sclp_vt220_lock, flags);
+ /* Move request from outqueue to empty queue */
+ list_del(&request->list);
+ sclp_vt220_outqueue_count--;
+ list_add_tail((struct list_head *) page, &sclp_vt220_empty);
+ /* Check if there is a pending buffer on the out queue. */
+ request = NULL;
+ if (!list_empty(&sclp_vt220_outqueue))
+ request = list_entry(sclp_vt220_outqueue.next,
+ struct sclp_vt220_request, list);
+ spin_unlock_irqrestore(&sclp_vt220_lock, flags);
+ } while (request && __sclp_vt220_emit(request));
+ if (request == NULL && sclp_vt220_flush_later)
sclp_vt220_emit_current();
wake_up(&sclp_vt220_waitq);
/* Check if the tty needs a wake up call */
}
}
-/*
- * Retry sclp write request after waiting some time for an sclp equipment
- * check to pass.
- */
-static void
-sclp_vt220_retry(unsigned long data)
-{
- struct sclp_vt220_request *request;
- struct sclp_vt220_sccb *sccb;
-
- request = (struct sclp_vt220_request *) data;
- request->sclp_req.status = SCLP_REQ_FILLED;
- sccb = (struct sclp_vt220_sccb *) request->sclp_req.sccb;
- sccb->header.response_code = 0x0000;
- sclp_add_request(&request->sclp_req);
-}
-
-#define SCLP_BUFFER_MAX_RETRY 5
-#define SCLP_BUFFER_RETRY_INTERVAL 2
+#define SCLP_BUFFER_MAX_RETRY 1
/*
* Callback through which the result of a write request is reported by the
break;
case 0x0340: /* Contained SCLP equipment check */
- if (vt220_request->retry_count++ > SCLP_BUFFER_MAX_RETRY)
+ if (++vt220_request->retry_count > SCLP_BUFFER_MAX_RETRY)
break;
/* Remove processed buffers and requeue rest */
if (sclp_remove_processed((struct sccb_header *) sccb) > 0) {
/* Not all buffers were processed */
sccb->header.response_code = 0x0000;
vt220_request->sclp_req.status = SCLP_REQ_FILLED;
- sclp_add_request(request);
- return;
+ if (sclp_add_request(request) == 0)
+ return;
}
break;
case 0x0040: /* SCLP equipment check */
- if (vt220_request->retry_count++ > SCLP_BUFFER_MAX_RETRY)
+ if (++vt220_request->retry_count > SCLP_BUFFER_MAX_RETRY)
break;
- /* Wait some time, then retry request */
- vt220_request->retry_timer.function = sclp_vt220_retry;
- vt220_request->retry_timer.data =
- (unsigned long) vt220_request;
- vt220_request->retry_timer.expires =
- jiffies + SCLP_BUFFER_RETRY_INTERVAL*HZ;
- add_timer(&vt220_request->retry_timer);
- return;
+ sccb->header.response_code = 0x0000;
+ vt220_request->sclp_req.status = SCLP_REQ_FILLED;
+ if (sclp_add_request(request) == 0)
+ return;
+ break;
default:
break;
}
/*
- * Emit vt220 request buffer to SCLP.
+ * Emit vt220 request buffer to SCLP. Return zero on success, non-zero
+ * otherwise.
*/
-static void
+static int
__sclp_vt220_emit(struct sclp_vt220_request *request)
{
if (!(sclp_vt220_register.sclp_send_mask & EvTyp_VT220Msg_Mask)) {
request->sclp_req.status = SCLP_REQ_FAILED;
- sclp_vt220_callback(&request->sclp_req, (void *) request);
- return;
+ return -EIO;
}
request->sclp_req.command = SCLP_CMDW_WRITEDATA;
request->sclp_req.status = SCLP_REQ_FILLED;
request->sclp_req.callback = sclp_vt220_callback;
request->sclp_req.callback_data = (void *) request;
- sclp_add_request(&request->sclp_req);
+ return sclp_add_request(&request->sclp_req);
}
/*
spin_unlock_irqrestore(&sclp_vt220_lock, flags);
/* Emit only the first buffer immediately - callback takes care of
* the rest */
- if (count == 0)
- __sclp_vt220_emit(request);
+ if (count == 0 && __sclp_vt220_emit(request))
+ sclp_vt220_process_queue(request);
}
/*
- * Queue and emit current request.
+ * Queue and emit current request. Return zero on success, non-zero otherwise.
*/
static void
sclp_vt220_emit_current(void)
/* Place request structure at end of page */
request = ((struct sclp_vt220_request *)
((addr_t) page + PAGE_SIZE)) - 1;
- init_timer(&request->retry_timer);
request->retry_count = 0;
request->sclp_req.sccb = page;
/* SCCB goes at start of page */
* number of characters actually accepted for writing.
*/
static int
-sclp_vt220_write(struct tty_struct *tty, int from_user,
- const unsigned char *buf, int count)
+sclp_vt220_write(struct tty_struct *tty, const unsigned char *buf, int count)
{
- int length;
- int ret;
-
- if (!from_user)
- return __sclp_vt220_write(buf, count, 1, 0);
- /* Use intermediate buffer to prevent calling copy_from_user() while
- * holding a lock. */
- ret = 0;
- while (count > 0) {
- length = count < SCLP_VT220_BUF_SIZE ?
- count : SCLP_VT220_BUF_SIZE;
- length -= copy_from_user(tty->driver_data,
- (const unsigned char __user *)buf, length);
- if (length == 0) {
- if (!ret)
- return -EFAULT;
- break;
- }
- length = __sclp_vt220_write(tty->driver_data, length, 1, 0);
- buf += length;
- count -= length;
- ret += length;
- }
- return ret;
+ return __sclp_vt220_write(buf, count, 1, 0);
}
#define SCLP_VT220_SESSION_ENDED 0x01
git://git.onelab.eu / linux-2.6.git / blobdiff