From 1a2ae03b1938b050c3bbd79e79d5075e0307fe20 Mon Sep 17 00:00:00 2001 From: Gerald Schaefer Date: Thu, 20 Feb 2020 16:22:30 +0100 Subject: s390/ipl: add support to control memory clearing for FCP and CCW re-IPL 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 Reviewed-by: Heiko Carstens Signed-off-by: Vasily Gorbik --- arch/s390/kernel/ipl.c | 73 +++++++++++++++++++++++++++++++++++++++++++++----- 1 file changed, 66 insertions(+), 7 deletions(-) (limited to 'arch/s390/kernel/ipl.c') diff --git a/arch/s390/kernel/ipl.c b/arch/s390/kernel/ipl.c index 6837affc19e8..4a71061974fd 100644 --- a/arch/s390/kernel/ipl.c +++ b/arch/s390/kernel/ipl.c @@ -144,6 +144,9 @@ static struct ipl_parameter_block *dump_block_ccw; 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_fcp_loadparm_attr = __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_attr_group = { .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_ccw_loadparm_attr = __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) -- cgit v1.2.3-59-g8ed1b