[patch 04/14] cio: Cleanup crw interface.
From: Martin Schwidefsky
Date: Tue Jun 03 2008 - 13:09:18 EST
From: Cornelia Huck <cornelia.huck@xxxxxxxxxx>
Eliminate the need for the machine check handler to call into
the common I/O layer directly by introducing an interface to
register handlers for crws per rsc.
Signed-off-by: Cornelia Huck <cornelia.huck@xxxxxxxxxx>
Signed-off-by: Martin Schwidefsky <schwidefsky@xxxxxxxxxx>
---
drivers/s390/cio/chp.c | 49 +++++++++++++++++++----
drivers/s390/cio/chp.h | 1
drivers/s390/cio/chsc.c | 25 +++++++++--
drivers/s390/cio/chsc.h | 2
drivers/s390/cio/css.c | 31 +++++++++++---
drivers/s390/cio/css.h | 1
drivers/s390/s390mach.c | 102 +++++++++++++++++++++---------------------------
drivers/s390/s390mach.h | 7 +++
8 files changed, 140 insertions(+), 78 deletions(-)
Index: quilt-2.6/drivers/s390/cio/chp.c
===================================================================
--- quilt-2.6.orig/drivers/s390/cio/chp.c
+++ quilt-2.6/drivers/s390/cio/chp.c
@@ -18,6 +18,7 @@
#include <asm/chpid.h>
#include <asm/sclp.h>
+#include "../s390mach.h"
#include "cio.h"
#include "css.h"
#include "ioasm.h"
@@ -476,24 +477,52 @@ void *chp_get_chp_desc(struct chp_id chp
/**
* chp_process_crw - process channel-path status change
- * @id: channel-path ID number
- * @status: non-zero if channel-path has become available, zero otherwise
+ * @crw0: channel report-word to handler
+ * @crw1: second channel-report word (always NULL)
+ * @overflow: crw overflow indication
*
* Handle channel-report-words indicating that the status of a channel-path
* has changed.
*/
-void chp_process_crw(int id, int status)
+static void chp_process_crw(struct crw *crw0, struct crw *crw1,
+ int overflow)
{
struct chp_id chpid;
+ if (overflow) {
+ css_schedule_eval_all();
+ return;
+ }
+ CIO_CRW_EVENT(2, "CRW reports slct=%d, oflw=%d, "
+ "chn=%d, rsc=%X, anc=%d, erc=%X, rsid=%X\n",
+ crw0->slct, crw0->oflw, crw0->chn, crw0->rsc, crw0->anc,
+ crw0->erc, crw0->rsid);
+ /*
+ * Check for solicited machine checks. These are
+ * created by reset channel path and need not be
+ * handled here.
+ */
+ if (crw0->slct) {
+ CIO_CRW_EVENT(2, "solicited machine check for "
+ "channel path %02X\n", crw0->rsid);
+ return;
+ }
chp_id_init(&chpid);
- chpid.id = id;
- if (status) {
+ chpid.id = crw0->rsid;
+ switch (crw0->erc) {
+ case CRW_ERC_IPARM: /* Path has come. */
if (!chp_is_registered(chpid))
chp_new(chpid);
chsc_chp_online(chpid);
- } else
+ break;
+ case CRW_ERC_PERRI: /* Path has gone. */
+ case CRW_ERC_PERRN:
chsc_chp_offline(chpid);
+ break;
+ default:
+ CIO_CRW_EVENT(2, "Don't know how to handle erc=%x\n",
+ crw0->erc);
+ }
}
int chp_ssd_get_mask(struct chsc_ssd_info *ssd, struct res_acc_data *data)
@@ -674,10 +703,16 @@ static int cfg_wait_idle(void)
static int __init chp_init(void)
{
struct chp_id chpid;
+ int ret;
+ ret = s390_register_crw_handler(CRW_RSC_CPATH, chp_process_crw);
+ if (ret)
+ return ret;
chp_wq = create_singlethread_workqueue("cio_chp");
- if (!chp_wq)
+ if (!chp_wq) {
+ s390_unregister_crw_handler(CRW_RSC_CPATH);
return -ENOMEM;
+ }
INIT_WORK(&cfg_work, cfg_func);
init_waitqueue_head(&cfg_wait_queue);
if (info_update())
Index: quilt-2.6/drivers/s390/cio/chp.h
===================================================================
--- quilt-2.6.orig/drivers/s390/cio/chp.h
+++ quilt-2.6/drivers/s390/cio/chp.h
@@ -54,7 +54,6 @@ int chp_get_status(struct chp_id chpid);
u8 chp_get_sch_opm(struct subchannel *sch);
int chp_is_registered(struct chp_id chpid);
void *chp_get_chp_desc(struct chp_id chpid);
-void chp_process_crw(int id, int available);
void chp_remove_cmg_attr(struct channel_path *chp);
int chp_add_cmg_attr(struct channel_path *chp);
int chp_new(struct chp_id chpid);
Index: quilt-2.6/drivers/s390/cio/chsc.c
===================================================================
--- quilt-2.6.orig/drivers/s390/cio/chsc.c
+++ quilt-2.6/drivers/s390/cio/chsc.c
@@ -16,6 +16,7 @@
#include <asm/cio.h>
#include <asm/chpid.h>
+#include "../s390mach.h"
#include "css.h"
#include "cio.h"
#include "cio_debug.h"
@@ -372,17 +373,25 @@ static void chsc_process_sei(struct chsc
}
}
-void chsc_process_crw(void)
+static void chsc_process_crw(struct crw *crw0, struct crw *crw1, int overflow)
{
struct chsc_sei_area *sei_area;
+ if (overflow) {
+ css_schedule_eval_all();
+ return;
+ }
+ CIO_CRW_EVENT(2, "CRW reports slct=%d, oflw=%d, "
+ "chn=%d, rsc=%X, anc=%d, erc=%X, rsid=%X\n",
+ crw0->slct, crw0->oflw, crw0->chn, crw0->rsc, crw0->anc,
+ crw0->erc, crw0->rsid);
if (!sei_page)
return;
/* Access to sei_page is serialized through machine check handler
* thread, so no need for locking. */
sei_area = sei_page;
- CIO_TRACE_EVENT( 2, "prcss");
+ CIO_TRACE_EVENT(2, "prcss");
do {
memset(sei_area, 0, sizeof(*sei_area));
sei_area->request.length = 0x0010;
@@ -751,15 +760,23 @@ out:
int __init chsc_alloc_sei_area(void)
{
+ int ret;
+
sei_page = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
- if (!sei_page)
+ if (!sei_page) {
CIO_MSG_EVENT(0, "Can't allocate page for processing of "
"chsc machine checks!\n");
- return (sei_page ? 0 : -ENOMEM);
+ return -ENOMEM;
+ }
+ ret = s390_register_crw_handler(CRW_RSC_CSS, chsc_process_crw);
+ if (ret)
+ kfree(sei_page);
+ return ret;
}
void __init chsc_free_sei_area(void)
{
+ s390_unregister_crw_handler(CRW_RSC_CSS);
kfree(sei_page);
}
Index: quilt-2.6/drivers/s390/cio/chsc.h
===================================================================
--- quilt-2.6.orig/drivers/s390/cio/chsc.h
+++ quilt-2.6/drivers/s390/cio/chsc.h
@@ -36,8 +36,6 @@ struct channel_path_desc {
struct channel_path;
-extern void chsc_process_crw(void);
-
struct css_general_char {
u64 : 41;
u32 aif : 1; /* bit 41 */
Index: quilt-2.6/drivers/s390/cio/css.c
===================================================================
--- quilt-2.6.orig/drivers/s390/cio/css.c
+++ quilt-2.6/drivers/s390/cio/css.c
@@ -14,6 +14,7 @@
#include <linux/list.h>
#include <linux/reboot.h>
+#include "../s390mach.h"
#include "css.h"
#include "cio.h"
#include "cio_debug.h"
@@ -530,18 +531,29 @@ EXPORT_SYMBOL_GPL(css_schedule_reprobe);
/*
* Called from the machine check handler for subchannel report words.
*/
-void css_process_crw(int rsid1, int rsid2)
+static void css_process_crw(struct crw *crw0, struct crw *crw1, int overflow)
{
struct subchannel_id mchk_schid;
- CIO_CRW_EVENT(2, "source is subchannel %04X, subsystem id %x\n",
- rsid1, rsid2);
+ if (overflow) {
+ css_schedule_eval_all();
+ return;
+ }
+ CIO_CRW_EVENT(2, "CRW0 reports slct=%d, oflw=%d, "
+ "chn=%d, rsc=%X, anc=%d, erc=%X, rsid=%X\n",
+ crw0->slct, crw0->oflw, crw0->chn, crw0->rsc, crw0->anc,
+ crw0->erc, crw0->rsid);
+ if (crw1)
+ CIO_CRW_EVENT(2, "CRW1 reports slct=%d, oflw=%d, "
+ "chn=%d, rsc=%X, anc=%d, erc=%X, rsid=%X\n",
+ crw1->slct, crw1->oflw, crw1->chn, crw1->rsc,
+ crw1->anc, crw1->erc, crw1->rsid);
init_subchannel_id(&mchk_schid);
- mchk_schid.sch_no = rsid1;
- if (rsid2 != 0)
- mchk_schid.ssid = (rsid2 >> 8) & 3;
+ mchk_schid.sch_no = crw0->rsid;
+ if (crw1)
+ mchk_schid.ssid = (crw1->rsid >> 8) & 3;
- /*
+ /*
* Since we are always presented with IPI in the CRW, we have to
* use stsch() to find out if the subchannel in question has come
* or gone.
@@ -740,6 +752,10 @@ init_channel_subsystem (void)
if (ret)
goto out;
+ ret = s390_register_crw_handler(CRW_RSC_SCH, css_process_crw);
+ if (ret)
+ goto out;
+
if ((ret = bus_register(&css_bus_type)))
goto out;
@@ -817,6 +833,7 @@ out_unregister:
out_bus:
bus_unregister(&css_bus_type);
out:
+ s390_unregister_crw_handler(CRW_RSC_CSS);
chsc_free_sei_area();
kfree(slow_subchannel_set);
printk(KERN_WARNING"cio: failed to initialize css driver (%d)!\n",
Index: quilt-2.6/drivers/s390/cio/css.h
===================================================================
--- quilt-2.6.orig/drivers/s390/cio/css.h
+++ quilt-2.6/drivers/s390/cio/css.h
@@ -103,7 +103,6 @@ int for_each_subchannel_staged(int (*fn_
int (*fn_unknown)(struct subchannel_id,
void *), void *data);
extern int for_each_subchannel(int(*fn)(struct subchannel_id, void *), void *);
-extern void css_process_crw(int, int);
extern void css_reiterate_subchannels(void);
void css_update_ssd_info(struct subchannel *sch);
Index: quilt-2.6/drivers/s390/s390mach.c
===================================================================
--- quilt-2.6.orig/drivers/s390/s390mach.c
+++ quilt-2.6/drivers/s390/s390mach.c
@@ -2,10 +2,10 @@
* drivers/s390/s390mach.c
* S/390 machine check handler
*
- * S390 version
- * Copyright (C) 2000 IBM Deutschland Entwicklung GmbH, IBM Corporation
+ * Copyright IBM Corp. 2000,2008
* Author(s): Ingo Adlung (adlung@xxxxxxxxxx)
* Martin Schwidefsky (schwidefsky@xxxxxxxxxx)
+ * Cornelia Huck <cornelia.huck@xxxxxxxxxx>
*/
#include <linux/init.h>
@@ -18,10 +18,6 @@
#include <asm/etr.h>
#include <asm/lowcore.h>
#include <asm/cio.h>
-#include "cio/cio.h"
-#include "cio/chsc.h"
-#include "cio/css.h"
-#include "cio/chp.h"
#include "s390mach.h"
static struct semaphore m_sem;
@@ -36,13 +32,40 @@ s390_handle_damage(char *msg)
for(;;);
}
+static crw_handler_t crw_handlers[NR_RSCS];
+
+/**
+ * s390_register_crw_handler() - register a channel report word handler
+ * @rsc: reporting source code to handle
+ * @handler: handler to be registered
+ *
+ * Returns %0 on success and a negative error value otherwise.
+ */
+int s390_register_crw_handler(int rsc, crw_handler_t handler)
+{
+ if ((rsc < 0) || (rsc >= NR_RSCS))
+ return -EINVAL;
+ if (!cmpxchg(&crw_handlers[rsc], NULL, handler))
+ return 0;
+ return -EBUSY;
+}
+
+/**
+ * s390_unregister_crw_handler() - unregister a channel report word handler
+ * @rsc: reporting source code to handle
+ */
+void s390_unregister_crw_handler(int rsc)
+{
+ if ((rsc < 0) || (rsc >= NR_RSCS))
+ return;
+ xchg(&crw_handlers[rsc], NULL);
+ synchronize_sched();
+}
+
/*
* Retrieve CRWs and call function to handle event.
- *
- * Note : we currently process CRWs for io and chsc subchannels only
*/
-static int
-s390_collect_crw_info(void *param)
+static int s390_collect_crw_info(void *param)
{
struct crw crw[2];
int ccode;
@@ -84,57 +107,24 @@ repeat:
crw[chain].rsid);
/* Check for overflows. */
if (crw[chain].oflw) {
+ int i;
+
pr_debug("%s: crw overflow detected!\n", __func__);
- css_schedule_eval_all();
+ for (i = 0; i < NR_RSCS; i++) {
+ if (crw_handlers[i])
+ crw_handlers[i](NULL, NULL, 1);
+ }
chain = 0;
continue;
}
- switch (crw[chain].rsc) {
- case CRW_RSC_SCH:
- if (crw[0].chn && !chain)
- break;
- pr_debug("source is subchannel %04X\n", crw[0].rsid);
- css_process_crw(crw[0].rsid, chain ? crw[1].rsid : 0);
- break;
- case CRW_RSC_MONITOR:
- pr_debug("source is monitoring facility\n");
- break;
- case CRW_RSC_CPATH:
- pr_debug("source is channel path %02X\n", crw[0].rsid);
- /*
- * Check for solicited machine checks. These are
- * created by reset channel path and need not be
- * reported to the common I/O layer.
- */
- if (crw[chain].slct) {
- pr_debug("solicited machine check for "
- "channel path %02X\n", crw[0].rsid);
- break;
- }
- switch (crw[0].erc) {
- case CRW_ERC_IPARM: /* Path has come. */
- chp_process_crw(crw[0].rsid, 1);
- break;
- case CRW_ERC_PERRI: /* Path has gone. */
- case CRW_ERC_PERRN:
- chp_process_crw(crw[0].rsid, 0);
- break;
- default:
- pr_debug("Don't know how to handle erc=%x\n",
- crw[0].erc);
- }
- break;
- case CRW_RSC_CONFIG:
- pr_debug("source is configuration-alert facility\n");
- break;
- case CRW_RSC_CSS:
- pr_debug("source is channel subsystem\n");
- chsc_process_crw();
- break;
- default:
- pr_debug("unknown source\n");
- break;
+ if (crw[0].chn && !chain) {
+ chain++;
+ continue;
}
+ if (crw_handlers[crw[chain].rsc])
+ crw_handlers[crw[chain].rsc](&crw[0],
+ chain ? &crw[1] : NULL,
+ 0);
/* chain is always 0 or 1 here. */
chain = crw[chain].chn ? chain + 1 : 0;
}
Index: quilt-2.6/drivers/s390/s390mach.h
===================================================================
--- quilt-2.6.orig/drivers/s390/s390mach.h
+++ quilt-2.6/drivers/s390/s390mach.h
@@ -72,6 +72,13 @@ struct crw {
__u32 rsid : 16; /* reporting-source ID */
} __attribute__ ((packed));
+typedef void (*crw_handler_t)(struct crw *, struct crw *, int);
+
+extern int s390_register_crw_handler(int rsc, crw_handler_t handler);
+extern void s390_unregister_crw_handler(int rsc);
+
+#define NR_RSCS 16
+
#define CRW_RSC_MONITOR 0x2 /* monitoring facility */
#define CRW_RSC_SCH 0x3 /* subchannel */
#define CRW_RSC_CPATH 0x4 /* channel path */
--
blue skies,
Martin.
"Reality continues to ruin my life." - Calvin.
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