[067/272] [S390] qdio: use proper QEBSM operand for SIGA-R and SIGA-S

Greg KH
2011-02-16T01:42:02Z

From: Jan Glauber <jang@linux.vnet.ibm.com>

commit 958c0ba403cb6a693b54be2389f9ef53377fa259 upstream.

If QIOASSIST is enabled for a qdio device the SIGA instruction requires
a modified function code. This function code modifier was missing for
SIGA-R and SIGA-S which can lead to a kernel panic caused by an
operand exception.

Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
drivers/s390/cio/qdio.h | 6 ++++++
drivers/s390/cio/qdio_main.c | 43 ++++++++++++++++++++++++++++---------------
2 files changed, 34 insertions(+), 15 deletions(-)

--- a/drivers/s390/cio/qdio.h
+++ b/drivers/s390/cio/qdio.h
@@ -91,6 +91,12 @@ enum qdio_irq_states {
#define AC1_SC_QEBSM_AVAILABLE 0x02 /* available for subchannel */
#define AC1_SC_QEBSM_ENABLED 0x01 /* enabled for subchannel */

+/* SIGA flags */
+#define QDIO_SIGA_WRITE 0x00
+#define QDIO_SIGA_READ 0x01
+#define QDIO_SIGA_SYNC 0x02
+#define QDIO_SIGA_QEBSM_FLAG 0x80
+
#ifdef CONFIG_64BIT
static inline int do_sqbs(u64 token, unsigned char state, int queue,
int *start, int *count)
--- a/drivers/s390/cio/qdio_main.c
+++ b/drivers/s390/cio/qdio_main.c
@@ -29,11 +29,12 @@ MODULE_AUTHOR("Utz Bacher <utz.bacher@de
MODULE_DESCRIPTION("QDIO base support");
MODULE_LICENSE("GPL");

-static inline int do_siga_sync(struct subchannel_id schid,
- unsigned int out_mask, unsigned int in_mask)
+static inline int do_siga_sync(unsigned long schid,
+ unsigned int out_mask, unsigned int in_mask,
+ unsigned int fc)
{
- register unsigned long __fc asm ("0") = 2;
- register struct subchannel_id __schid asm ("1") = schid;
+ register unsigned long __fc asm ("0") = fc;
+ register unsigned long __schid asm ("1") = schid;
register unsigned long out asm ("2") = out_mask;
register unsigned long in asm ("3") = in_mask;
int cc;
@@ -47,10 +48,11 @@ static inline int do_siga_sync(struct su
return cc;
}

-static inline int do_siga_input(struct subchannel_id schid, unsigned int mask)
+static inline int do_siga_input(unsigned long schid, unsigned int mask,
+ unsigned int fc)
{
- register unsigned long __fc asm ("0") = 1;
- register struct subchannel_id __schid asm ("1") = schid;
+ register unsigned long __fc asm ("0") = fc;
+ register unsigned long __schid asm ("1") = schid;
register unsigned long __mask asm ("2") = mask;
int cc;

@@ -279,6 +281,8 @@ void qdio_init_buf_states(struct qdio_ir
static inline int qdio_siga_sync(struct qdio_q *q, unsigned int output,
unsigned int input)
{
+ unsigned long schid = *((u32 *) &q->irq_ptr->schid);
+ unsigned int fc = QDIO_SIGA_SYNC;
int cc;

if (!need_siga_sync(q))
@@ -287,7 +291,12 @@ static inline int qdio_siga_sync(struct
DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "siga-s:%1d", q->nr);
qperf_inc(q, siga_sync);

- cc = do_siga_sync(q->irq_ptr->schid, output, input);
+ if (is_qebsm(q)) {
+ schid = q->irq_ptr->sch_token;
+ fc |= QDIO_SIGA_QEBSM_FLAG;
+ }
+
+ cc = do_siga_sync(schid, output, input, fc);
if (cc)
DBF_ERROR("%4x SIGA-S:%2d", SCH_NO(q), cc);
return cc;
@@ -313,8 +322,8 @@ static inline int qdio_siga_sync_all(str

static int qdio_siga_output(struct qdio_q *q, unsigned int *busy_bit)
{
- unsigned long schid;
- unsigned int fc = 0;
+ unsigned long schid = *((u32 *) &q->irq_ptr->schid);
+ unsigned int fc = QDIO_SIGA_WRITE;
u64 start_time = 0;
int cc;

@@ -323,11 +332,8 @@ static int qdio_siga_output(struct qdio_

if (is_qebsm(q)) {
schid = q->irq_ptr->sch_token;
- fc |= 0x80;
+ fc |= QDIO_SIGA_QEBSM_FLAG;
}
- else
- schid = *((u32 *)&q->irq_ptr->schid);
-
again:
cc = do_siga_output(schid, q->mask, busy_bit, fc);

@@ -347,12 +353,19 @@ again:

static inline int qdio_siga_input(struct qdio_q *q)
{
+ unsigned long schid = *((u32 *) &q->irq_ptr->schid);
+ unsigned int fc = QDIO_SIGA_READ;
int cc;

DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "siga-r:%1d", q->nr);
qperf_inc(q, siga_read);

- cc = do_siga_input(q->irq_ptr->schid, q->mask);
+ if (is_qebsm(q)) {
+ schid = q->irq_ptr->sch_token;
+ fc |= QDIO_SIGA_QEBSM_FLAG;
+ }
+
+ cc = do_siga_input(schid, q->mask, fc);
if (cc)
DBF_ERROR("%4x SIGA-R:%2d", SCH_NO(q), cc);
return cc;