From: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Date: Thu, 20 Feb 2020 16:22:30 +0100
Subject: s390/ipl: add support to control memory clearing for FCP and CCW
re-IPL
Git-commit: 1a2ae03b1938b050c3bbd79e79d5075e0307fe20
Patch-mainline: v5.7-rc1
References: jsc#SLE-13740
Re-IPL for both CCW and FCP is currently done by using diag 308 with the
"Load Clear" subcode, which means that all memory will be cleared.
This can increase re-IPL duration considerably on very large machines.
For CCW devices, there is also a "Load Normal" subcode that was only used
for dump kernels so far. For FCP devices, a similar "Load Normal" subcode
was introduced with z14. The "Load Normal" diag 308 subcode allows to
re-IPL without clearing memory.
This patch adds a new "clear" sysfs attribute to /sys/firmware/reipl for
both the ccw and fcp subdirectories, which can be set to either "0" or "1"
to disable or enable re-IPL with memory clearing. The default value is "0",
which disables memory clearing.
Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Acked-by: Petr Tesarik <ptesarik@suse.com>
---
arch/s390/include/asm/ipl.h | 1
arch/s390/kernel/ipl.c | 73 +++++++++++++++++++++++++++++++++++++++-----
2 files changed, 67 insertions(+), 7 deletions(-)
--- a/arch/s390/include/asm/ipl.h
+++ b/arch/s390/include/asm/ipl.h
@@ -119,6 +119,7 @@ enum diag308_subcode {
DIAG308_LOAD_NORMAL_DUMP = 4,
DIAG308_SET = 5,
DIAG308_STORE = 6,
+ DIAG308_LOAD_NORMAL = 7,
};
enum diag308_rc {
--- a/arch/s390/kernel/ipl.c
+++ b/arch/s390/kernel/ipl.c
@@ -144,6 +144,9 @@ static struct ipl_parameter_block *dump_
static struct sclp_ipl_info sclp_ipl_info;
+static bool reipl_fcp_clear;
+static bool reipl_ccw_clear;
+
static inline int __diag308(unsigned long subcode, void *addr)
{
register unsigned long _addr asm("0") = (unsigned long) addr;
@@ -691,6 +694,21 @@ static struct kobj_attribute sys_reipl_f
__ATTR(loadparm, S_IRUGO | S_IWUSR, reipl_fcp_loadparm_show,
reipl_fcp_loadparm_store);
+static ssize_t reipl_fcp_clear_show(struct kobject *kobj,
+ struct kobj_attribute *attr, char *page)
+{
+ return sprintf(page, "%u\n", reipl_fcp_clear);
+}
+
+static ssize_t reipl_fcp_clear_store(struct kobject *kobj,
+ struct kobj_attribute *attr,
+ const char *buf, size_t len)
+{
+ if (strtobool(buf, &reipl_fcp_clear) < 0)
+ return -EINVAL;
+ return len;
+}
+
static struct attribute *reipl_fcp_attrs[] = {
&sys_reipl_fcp_device_attr.attr,
&sys_reipl_fcp_wwpn_attr.attr,
@@ -706,6 +724,9 @@ static struct attribute_group reipl_fcp_
.bin_attrs = reipl_fcp_bin_attrs,
};
+static struct kobj_attribute sys_reipl_fcp_clear_attr =
+ __ATTR(clear, 0644, reipl_fcp_clear_show, reipl_fcp_clear_store);
+
/* CCW reipl device attributes */
DEFINE_IPL_CCW_ATTR_RW(reipl_ccw, device, reipl_block_ccw->ccw);
@@ -741,16 +762,36 @@ static struct kobj_attribute sys_reipl_c
__ATTR(loadparm, S_IRUGO | S_IWUSR, reipl_ccw_loadparm_show,
reipl_ccw_loadparm_store);
+static ssize_t reipl_ccw_clear_show(struct kobject *kobj,
+ struct kobj_attribute *attr, char *page)
+{
+ return sprintf(page, "%u\n", reipl_ccw_clear);
+}
+
+static ssize_t reipl_ccw_clear_store(struct kobject *kobj,
+ struct kobj_attribute *attr,
+ const char *buf, size_t len)
+{
+ if (strtobool(buf, &reipl_ccw_clear) < 0)
+ return -EINVAL;
+ return len;
+}
+
+static struct kobj_attribute sys_reipl_ccw_clear_attr =
+ __ATTR(clear, 0644, reipl_ccw_clear_show, reipl_ccw_clear_store);
+
static struct attribute *reipl_ccw_attrs_vm[] = {
&sys_reipl_ccw_device_attr.attr,
&sys_reipl_ccw_loadparm_attr.attr,
&sys_reipl_ccw_vmparm_attr.attr,
+ &sys_reipl_ccw_clear_attr.attr,
NULL,
};
static struct attribute *reipl_ccw_attrs_lpar[] = {
&sys_reipl_ccw_device_attr.attr,
&sys_reipl_ccw_loadparm_attr.attr,
+ &sys_reipl_ccw_clear_attr.attr,
NULL,
};
@@ -892,11 +933,17 @@ static void __reipl_run(void *unused)
switch (reipl_type) {
case IPL_TYPE_CCW:
diag308(DIAG308_SET, reipl_block_ccw);
- diag308(DIAG308_LOAD_CLEAR, NULL);
+ if (reipl_ccw_clear)
+ diag308(DIAG308_LOAD_CLEAR, NULL);
+ else
+ diag308(DIAG308_LOAD_NORMAL_DUMP, NULL);
break;
case IPL_TYPE_FCP:
diag308(DIAG308_SET, reipl_block_fcp);
- diag308(DIAG308_LOAD_CLEAR, NULL);
+ if (reipl_fcp_clear)
+ diag308(DIAG308_LOAD_CLEAR, NULL);
+ else
+ diag308(DIAG308_LOAD_NORMAL, NULL);
break;
case IPL_TYPE_NSS:
diag308(DIAG308_SET, reipl_block_nss);
@@ -1008,11 +1055,16 @@ static int __init reipl_fcp_init(void)
}
rc = sysfs_create_group(&reipl_fcp_kset->kobj, &reipl_fcp_attr_group);
- if (rc) {
- kset_unregister(reipl_fcp_kset);
- free_page((unsigned long) reipl_block_fcp);
- return rc;
- }
+ if (rc)
+ goto out1;
+
+ if (test_facility(141)) {
+ rc = sysfs_create_file(&reipl_fcp_kset->kobj,
+ &sys_reipl_fcp_clear_attr.attr);
+ if (rc)
+ goto out2;
+ } else
+ reipl_fcp_clear = true;
if (ipl_info.type == IPL_TYPE_FCP) {
memcpy(reipl_block_fcp, &ipl_block, sizeof(ipl_block));
@@ -1032,6 +1084,13 @@ static int __init reipl_fcp_init(void)
}
reipl_capabilities |= IPL_TYPE_FCP;
return 0;
+
+out2:
+ sysfs_remove_group(&reipl_fcp_kset->kobj, &reipl_fcp_attr_group);
+out1:
+ kset_unregister(reipl_fcp_kset);
+ free_page((unsigned long) reipl_block_fcp);
+ return rc;
}
static int __init reipl_type_init(void)