[PATCH] s390: introduce for_each_subchannel
for_each_subchannel() is an iterator calling a function for every possible
subchannel id until non-zero is returned. Convert the current iterating
functions to it.
Signed-off-by: Cornelia Huck <cohuck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/drivers/s390/cio/css.c b/drivers/s390/cio/css.c
index 5137daf..dba632a 100644
--- a/drivers/s390/cio/css.c
+++ b/drivers/s390/cio/css.c
@@ -21,7 +21,6 @@
#include "ioasm.h"
#include "chsc.h"
-unsigned int highest_subchannel;
int need_rescan = 0;
int css_init_done = 0;
@@ -32,6 +31,22 @@
.bus_id = "css0",
};
+inline int
+for_each_subchannel(int(*fn)(struct subchannel_id, void *), void *data)
+{
+ struct subchannel_id schid;
+ int ret;
+
+ init_subchannel_id(&schid);
+ ret = -ENODEV;
+ do {
+ ret = fn(schid, data);
+ if (ret)
+ break;
+ } while (schid.sch_no++ < __MAX_SUBCHANNEL);
+ return ret;
+}
+
static struct subchannel *
css_alloc_subchannel(struct subchannel_id schid)
{
@@ -280,25 +295,10 @@
return ret;
}
-static void
-css_rescan_devices(void)
+static int
+css_rescan_devices(struct subchannel_id schid, void *data)
{
- int ret;
- struct subchannel_id schid;
-
- init_subchannel_id(&schid);
- do {
- ret = css_evaluate_subchannel(schid, 1);
- /* No more memory. It doesn't make sense to continue. No
- * panic because this can happen in midflight and just
- * because we can't use a new device is no reason to crash
- * the system. */
- if (ret == -ENOMEM)
- break;
- /* -ENXIO indicates that there are no more subchannels. */
- if (ret == -ENXIO)
- break;
- } while (schid.sch_no++ < __MAX_SUBCHANNEL);
+ return css_evaluate_subchannel(schid, 1);
}
struct slow_subchannel {
@@ -316,7 +316,7 @@
if (need_rescan) {
need_rescan = 0;
- css_rescan_devices();
+ for_each_subchannel(css_rescan_devices, NULL);
return;
}
@@ -383,6 +383,43 @@
return ret;
}
+static int __init
+__init_channel_subsystem(struct subchannel_id schid, void *data)
+{
+ struct subchannel *sch;
+ int ret;
+
+ if (cio_is_console(schid))
+ sch = cio_get_console_subchannel();
+ else {
+ sch = css_alloc_subchannel(schid);
+ if (IS_ERR(sch))
+ ret = PTR_ERR(sch);
+ else
+ ret = 0;
+ switch (ret) {
+ case 0:
+ break;
+ case -ENOMEM:
+ panic("Out of memory in init_channel_subsystem\n");
+ /* -ENXIO: no more subchannels. */
+ case -ENXIO:
+ return ret;
+ default:
+ return 0;
+ }
+ }
+ /*
+ * We register ALL valid subchannels in ioinfo, even those
+ * that have been present before init_channel_subsystem.
+ * These subchannels can't have been registered yet (kmalloc
+ * not working) so we do it now. This is true e.g. for the
+ * console subchannel.
+ */
+ css_register_subchannel(sch);
+ return 0;
+}
+
static void __init
css_generate_pgid(void)
{
@@ -410,7 +447,6 @@
init_channel_subsystem (void)
{
int ret;
- struct subchannel_id schid;
if (chsc_determine_css_characteristics() == 0)
css_characteristics_avail = 1;
@@ -426,38 +462,8 @@
ctl_set_bit(6, 28);
- init_subchannel_id(&schid);
- do {
- struct subchannel *sch;
-
- if (cio_is_console(schid))
- sch = cio_get_console_subchannel();
- else {
- sch = css_alloc_subchannel(schid);
- if (IS_ERR(sch))
- ret = PTR_ERR(sch);
- else
- ret = 0;
- if (ret == -ENOMEM)
- panic("Out of memory in "
- "init_channel_subsystem\n");
- /* -ENXIO: no more subchannels. */
- if (ret == -ENXIO)
- break;
- if (ret)
- continue;
- }
- /*
- * We register ALL valid subchannels in ioinfo, even those
- * that have been present before init_channel_subsystem.
- * These subchannels can't have been registered yet (kmalloc
- * not working) so we do it now. This is true e.g. for the
- * console subchannel.
- */
- css_register_subchannel(sch);
- } while (schid.sch_no++ < __MAX_SUBCHANNEL);
+ for_each_subchannel(__init_channel_subsystem, NULL);
return 0;
-
out_bus:
bus_unregister(&css_bus_type);
out: