Commit bffbbd2d authored by Jan Glauber's avatar Jan Glauber Committed by Martin Schwidefsky
Browse files

[S390] qdio: reset error states immediately 



The qdio hardware may surpress further interrupts as long as a SBAL is in
the error state. That can lead to unnotified data in the SBALs following
the error state. To prevent this behaviour change the SBAL[s] in error
state immediately to another program owned state so interrupts are again
received for further traffic on the device.

Signed-off-by: default avatarJan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
parent e4c031b4

drivers/s390/cio/qdio_main.c

+12 −5
Original line number Diff line number Diff line
@@ -407,8 +407,11 @@ static inline void account_sbals(struct qdio_q *q, int count) 
	q->q_stats.nr_sbals[pos]++;

}



static void announce_buffer_error(struct qdio_q *q, int count)

static void process_buffer_error(struct qdio_q *q, int count)

{

	unsigned char state = (q->is_input_q) ? SLSB_P_INPUT_NOT_INIT :

					SLSB_P_OUTPUT_NOT_INIT;



	q->qdio_error |= QDIO_ERROR_SLSB_STATE;



	/* special handling for no target buffer empty */
@@ -426,6 +429,12 @@ static void announce_buffer_error(struct qdio_q *q, int count) 
	DBF_ERROR("F14:%2x F15:%2x",

		  q->sbal[q->first_to_check]->element[14].flags & 0xff,

		  q->sbal[q->first_to_check]->element[15].flags & 0xff);



	/*

	 * Interrupts may be avoided as long as the error is present

	 * so change the buffer state immediately to avoid starvation.

	 */

	set_buf_states(q, q->first_to_check, state, count);

}



static inline void inbound_primed(struct qdio_q *q, int count)
@@ -506,8 +515,7 @@ static int get_inbound_buffer_frontier(struct qdio_q *q) 
			account_sbals(q, count);

		break;

	case SLSB_P_INPUT_ERROR:

		announce_buffer_error(q, count);

		/* process the buffer, the upper layer will take care of it */

		process_buffer_error(q, count);

		q->first_to_check = add_buf(q->first_to_check, count);

		atomic_sub(count, &q->nr_buf_used);

		if (q->irq_ptr->perf_stat_enabled)
@@ -677,8 +685,7 @@ static int get_outbound_buffer_frontier(struct qdio_q *q) 
			account_sbals(q, count);

		break;

	case SLSB_P_OUTPUT_ERROR:

		announce_buffer_error(q, count);

		/* process the buffer, the upper layer will take care of it */

		process_buffer_error(q, count);

		q->first_to_check = add_buf(q->first_to_check, count);

		atomic_sub(count, &q->nr_buf_used);

		if (q->irq_ptr->perf_stat_enabled)

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