[S390] cio: introduce cio_commit_config
To change the configuration of a subchannel we alter the modifiable
bits of the subchannel's schib field and issue a modify subchannel.
There can be the case that not all changes were applied -or worse-
quietly overwritten by the hardware. With the next store subchannel
we obtain the current state of the hardware but lose our target
configuration.
With this patch we introduce a subchannel_config structure which
contains the target subchannel configuration. Additionally the msch
wrapper cio_modify is replaced with cio_commit_config which
copies the desired changes to a temporary schib. msch is then
called with the temporary schib. This schib is only written back
to the subchannel if all changes were applied.
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/drivers/s390/cio/cio.h b/drivers/s390/cio/cio.h
index fb125ef..5150fba 100644
--- a/drivers/s390/cio/cio.h
+++ b/drivers/s390/cio/cio.h
@@ -45,6 +45,19 @@
/* ... in an operand exception. */
} __attribute__ ((packed));
+/* Target SCHIB configuration. */
+struct schib_config {
+ u64 mba;
+ u32 intparm;
+ u16 mbi;
+ u32 isc:3;
+ u32 ena:1;
+ u32 mme:2;
+ u32 mp:1;
+ u32 csense:1;
+ u32 mbfc:1;
+} __attribute__ ((packed));
+
/*
* subchannel information block
*/
@@ -83,6 +96,7 @@
struct css_driver *driver;
void *private; /* private per subchannel type data */
struct work_struct work;
+ struct schib_config config;
} __attribute__ ((aligned(8)));
#define IO_INTERRUPT_TYPE 0 /* I/O interrupt type */
@@ -101,8 +115,8 @@
extern int cio_cancel (struct subchannel *);
extern int cio_set_options (struct subchannel *, int);
extern int cio_get_options (struct subchannel *);
-extern int cio_modify (struct subchannel *);
extern int cio_update_schib(struct subchannel *sch);
+extern int cio_commit_config(struct subchannel *sch);
int cio_tm_start_key(struct subchannel *sch, struct tcw *tcw, u8 lpm, u8 key);
int cio_tm_intrg(struct subchannel *sch);