[S390] Reset infrastructure for re-IPL.

In case of re-IPL and diag308 doesn't work we have to reset all devices manually and wait synchronously that each reset finished. This patch adds the necessary infrastucture and the first exploiter of it. Subsystems that need to add a function that needs to be called at re-IPL may register/unregister this function via struct reset_call { struct reset_call *next; void (*fn)(void); }; void register_reset_call(struct reset_call *reset); void unregister_reset_call(struct reset_call *reset); When the registered function get called the context is: - all cpus beside the current one are stopped - all machine checks and interrupts are disabled - prefixing is disabled - a default machine check handler is available for use The registered functions may not take any locks are sleep. For the common I/O layer part of this patch: Introduce a reset_call css_reset that does the following: - clear all subchannels - perform a rchp on all channel paths and wait for the resulting machine checks This replaces the calls to clear_all_subchannels() and cio_reset_channel_paths() for kexec and ccw reipl. reipl_ccw_dev() now uses reipl_find_schid() to determine the subchannel id for a given device id. Also remove cio_reset_channel_paths() and friends since they are not needed anymore. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
git-mirror · Dec 4, 2006 · 15e9b58 · 15e9b58
1 parent 2254f5a
commit 15e9b58
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Showing 13 changed files with 246 additions and 108 deletions.
diff --git a/arch/s390/kernel/Makefile b/arch/s390/kernel/Makefile
@@ -4,7 +4,7 @@
 
 EXTRA_AFLAGS	:= -traditional
 
-obj-y	:=  bitmap.o traps.o time.o process.o \
+obj-y	:=  bitmap.o traps.o time.o process.o reset.o \
             setup.o sys_s390.o ptrace.o signal.o cpcmd.o ebcdic.o \
 	    semaphore.o s390_ext.o debug.o profile.o irq.o ipl.o
 

diff --git a/arch/s390/kernel/ipl.c b/arch/s390/kernel/ipl.c
@@ -19,6 +19,7 @@
 #include <asm/cpcmd.h>
 #include <asm/cio.h>
 #include <asm/ebcdic.h>
+#include <asm/reset.h>
 
 #define IPL_PARM_BLOCK_VERSION 0
 #define LOADPARM_LEN 8
@@ -1024,3 +1025,56 @@ static int __init s390_ipl_init(void)
 }
 
 __initcall(s390_ipl_init);
+
+static LIST_HEAD(rcall);
+static DEFINE_MUTEX(rcall_mutex);
+
+void register_reset_call(struct reset_call *reset)
+{
+	mutex_lock(&rcall_mutex);
+	list_add(&reset->list, &rcall);
+	mutex_unlock(&rcall_mutex);
+}
+EXPORT_SYMBOL_GPL(register_reset_call);
+
+void unregister_reset_call(struct reset_call *reset)
+{
+	mutex_lock(&rcall_mutex);
+	list_del(&reset->list);
+	mutex_unlock(&rcall_mutex);
+}
+EXPORT_SYMBOL_GPL(unregister_reset_call);
+
+static void do_reset_calls(void)
+{
+	struct reset_call *reset;
+
+	list_for_each_entry(reset, &rcall, list)
+		reset->fn();
+}
+
+extern void reset_mcck_handler(void);
+
+void s390_reset_system(void)
+{
+	struct _lowcore *lc;
+
+	/* Disable all interrupts/machine checks */
+	__load_psw_mask(PSW_KERNEL_BITS & ~PSW_MASK_MCHECK);
+
+	/* Stack for interrupt/machine check handler */
+	lc = (struct _lowcore *)(unsigned long) store_prefix();
+	lc->panic_stack = S390_lowcore.panic_stack;
+
+	/* Disable prefixing */
+	set_prefix(0);
+
+	/* Disable lowcore protection */
+	__ctl_clear_bit(0,28);
+
+	/* Set new machine check handler */
+	S390_lowcore.mcck_new_psw.mask = PSW_KERNEL_BITS & ~PSW_MASK_MCHECK;
+	S390_lowcore.mcck_new_psw.addr =
+		PSW_ADDR_AMODE | (unsigned long) &reset_mcck_handler;
+	do_reset_calls();
+}
diff --git a/arch/s390/kernel/machine_kexec.c b/arch/s390/kernel/machine_kexec.c
@@ -22,6 +22,7 @@
 #include <asm/pgalloc.h>
 #include <asm/system.h>
 #include <asm/smp.h>
+#include <asm/reset.h>
 
 static void kexec_halt_all_cpus(void *);
 
@@ -62,12 +63,6 @@ machine_shutdown(void)
 NORET_TYPE void
 machine_kexec(struct kimage *image)
 {
-	clear_all_subchannels();
-	cio_reset_channel_paths();
-
-	/* Disable lowcore protection */
-	ctl_clear_bit(0,28);
-
 	on_each_cpu(kexec_halt_all_cpus, image, 0, 0);
 	for (;;);
 }
@@ -98,6 +93,8 @@ kexec_halt_all_cpus(void *kernel_image)
 			cpu_relax();
 	}
 
+	s390_reset_system();
+
 	image = (struct kimage *) kernel_image;
 	data_mover = (relocate_kernel_t)
 		(page_to_pfn(image->control_code_page) << PAGE_SHIFT);

diff --git a/arch/s390/kernel/reipl.S b/arch/s390/kernel/reipl.S
@@ -11,19 +11,10 @@
 		.globl	do_reipl_asm
 do_reipl_asm:	basr	%r13,0
 .Lpg0:		lpsw	.Lnewpsw-.Lpg0(%r13)
-
-		# switch off lowcore protection
-
-.Lpg1:		stctl	%c0,%c0,.Lctlsave1-.Lpg0(%r13)
-		stctl	%c0,%c0,.Lctlsave2-.Lpg0(%r13)
-		ni	.Lctlsave1-.Lpg0(%r13),0xef
-		lctl	%c0,%c0,.Lctlsave1-.Lpg0(%r13)
-
-		# do store status of all registers
+.Lpg1:		# do store status of all registers
 
 		stm	%r0,%r15,__LC_GPREGS_SAVE_AREA
 		stctl	%c0,%c15,__LC_CREGS_SAVE_AREA
-		mvc	__LC_CREGS_SAVE_AREA(4),.Lctlsave2-.Lpg0(%r13)
 		stam	%a0,%a15,__LC_AREGS_SAVE_AREA
 		stpx	__LC_PREFIX_SAVE_AREA
 		stckc	.Lclkcmp-.Lpg0(%r13)
@@ -56,18 +47,14 @@ do_reipl_asm:	basr	%r13,0
 .L002:		tm	.Liplirb+8-.Lpg0(%r13),0xf3
 		jz	.L003
 		bas	%r14,.Ldisab-.Lpg0(%r13)
-.L003:		spx	.Lnull-.Lpg0(%r13)
-		st	%r1,__LC_SUBCHANNEL_ID
+.L003:		st	%r1,__LC_SUBCHANNEL_ID
 		lpsw	0
 		sigp	0,0,0(6)
 .Ldisab:	st	%r14,.Ldispsw+4-.Lpg0(%r13)
 		lpsw	.Ldispsw-.Lpg0(%r13)
 		.align	8
 .Lclkcmp:	.quad	0x0000000000000000
 .Lall:		.long	0xff000000
-.Lnull:		.long	0x00000000
-.Lctlsave1:	.long	0x00000000
-.Lctlsave2:	.long	0x00000000
 		.align	8
 .Lnewpsw:	.long	0x00080000,0x80000000+.Lpg1
 .Lpcnew:	.long	0x00080000,0x80000000+.Lecs

diff --git a/arch/s390/kernel/reipl64.S b/arch/s390/kernel/reipl64.S
@@ -10,10 +10,10 @@
 #include <asm/lowcore.h>
 		.globl	do_reipl_asm
 do_reipl_asm:	basr	%r13,0
+.Lpg0:		lpswe	.Lnewpsw-.Lpg0(%r13)
+.Lpg1:		# do store status of all registers
 
-		# do store status of all registers
-
-.Lpg0:		stg	%r1,.Lregsave-.Lpg0(%r13)
+		stg	%r1,.Lregsave-.Lpg0(%r13)
 		lghi	%r1,0x1000
 		stmg	%r0,%r15,__LC_GPREGS_SAVE_AREA-0x1000(%r1)
 		lg	%r0,.Lregsave-.Lpg0(%r13)
@@ -27,11 +27,7 @@ do_reipl_asm:	basr	%r13,0
 		stpt	__LC_CPU_TIMER_SAVE_AREA-0x1000(%r1)
 		stg	%r13, __LC_PSW_SAVE_AREA-0x1000+8(%r1)
 
-		lpswe	.Lnewpsw-.Lpg0(%r13)
-.Lpg1:		lctlg	%c6,%c6,.Lall-.Lpg0(%r13)
-		stctg	%c0,%c0,.Lregsave-.Lpg0(%r13)
-		ni	.Lregsave+4-.Lpg0(%r13),0xef
-		lctlg	%c0,%c0,.Lregsave-.Lpg0(%r13)
+		lctlg	%c6,%c6,.Lall-.Lpg0(%r13)
 		lgr	%r1,%r2
 		mvc	__LC_PGM_NEW_PSW(16),.Lpcnew-.Lpg0(%r13)
 		stsch	.Lschib-.Lpg0(%r13)
@@ -56,8 +52,7 @@ do_reipl_asm:	basr	%r13,0
 .L002:		tm	.Liplirb+8-.Lpg0(%r13),0xf3
 		jz	.L003
 		bas	%r14,.Ldisab-.Lpg0(%r13)
-.L003:		spx	.Lnull-.Lpg0(%r13)
-		st	%r1,__LC_SUBCHANNEL_ID
+.L003:		st	%r1,__LC_SUBCHANNEL_ID
 		lhi	%r1,0		 # mode 0 = esa
 		slr	%r0,%r0 	 # set cpuid to zero
 		sigp	%r1,%r0,0x12	 # switch to esa mode
@@ -70,7 +65,6 @@ do_reipl_asm:	basr	%r13,0
 .Lclkcmp:	.quad	0x0000000000000000
 .Lall:		.quad	0x00000000ff000000
 .Lregsave:	.quad	0x0000000000000000
-.Lnull:		.long	0x0000000000000000
 		.align	16
 /*
  * These addresses have to be 31 bit otherwise

diff --git a/arch/s390/kernel/relocate_kernel.S b/arch/s390/kernel/relocate_kernel.S
@@ -26,8 +26,7 @@
 	relocate_kernel:
 		basr	%r13,0		# base address
 	.base:
-		stnsm	sys_msk-.base(%r13),0xf8	# disable DAT and IRQ (external)
-		spx	zero64-.base(%r13)	# absolute addressing mode
+		stnsm	sys_msk-.base(%r13),0xfb	# disable DAT
 		stctl	%c0,%c15,ctlregs-.base(%r13)
 		stm	%r0,%r15,gprregs-.base(%r13)
 		la	%r1,load_psw-.base(%r13)
@@ -97,8 +96,6 @@
 		lpsw	0		# hopefully start new kernel...
 
 		.align	8
-	zero64:
-		.quad	0
 	load_psw:
 		.long	0x00080000,0x80000000
 	sys_msk:

diff --git a/arch/s390/kernel/relocate_kernel64.S b/arch/s390/kernel/relocate_kernel64.S
@@ -27,8 +27,7 @@
 	relocate_kernel:
 		basr	%r13,0		# base address
 	.base:
-		stnsm	sys_msk-.base(%r13),0xf8	# disable DAT and IRQs
-		spx	zero64-.base(%r13)	# absolute addressing mode
+		stnsm	sys_msk-.base(%r13),0xfb	# disable DAT
 		stctg	%c0,%c15,ctlregs-.base(%r13)
 		stmg	%r0,%r15,gprregs-.base(%r13)
 		lghi	%r0,3
@@ -100,8 +99,6 @@
 		lpsw	0		# hopefully start new kernel...
 
 		.align	8
-	zero64:
-		.quad	0
 	load_psw:
 		.long	0x00080000,0x80000000
 	sys_msk:

diff --git a/arch/s390/kernel/reset.S b/arch/s390/kernel/reset.S
@@ -0,0 +1,48 @@
+/*
+ *  arch/s390/kernel/reset.S
+ *
+ *    Copyright (C) IBM Corp. 2006
+ *    Author(s): Heiko Carstens <heiko.carstens@de.ibm.com>
+ */
+
+#include <asm/ptrace.h>
+#include <asm/lowcore.h>
+
+#ifdef CONFIG_64BIT
+
+	.globl	reset_mcck_handler
+reset_mcck_handler:
+	basr	%r13,0
+0:	lg	%r15,__LC_PANIC_STACK	# load panic stack
+	aghi	%r15,-STACK_FRAME_OVERHEAD
+	lg	%r1,s390_reset_mcck_handler-0b(%r13)
+	ltgr	%r1,%r1
+	jz	1f
+	basr	%r14,%r1
+1:	la	%r1,4095
+	lmg	%r0,%r15,__LC_GPREGS_SAVE_AREA-4095(%r1)
+	lpswe	__LC_MCK_OLD_PSW
+
+	.globl	s390_reset_mcck_handler
+s390_reset_mcck_handler:
+	.quad	0
+
+#else /* CONFIG_64BIT */
+
+	.globl	reset_mcck_handler
+reset_mcck_handler:
+	basr	%r13,0
+0:	l	%r15,__LC_PANIC_STACK	# load panic stack
+	ahi	%r15,-STACK_FRAME_OVERHEAD
+	l	%r1,s390_reset_mcck_handler-0b(%r13)
+	ltr	%r1,%r1
+	jz	1f
+	basr	%r14,%r1
+1:	lm	%r0,%r15,__LC_GPREGS_SAVE_AREA
+	lpsw	__LC_MCK_OLD_PSW
+
+	.globl	s390_reset_mcck_handler
+s390_reset_mcck_handler:
+	.long	0
+
+#endif /* CONFIG_64BIT */
diff --git a/drivers/s390/cio/chsc.c b/drivers/s390/cio/chsc.c
@@ -1465,41 +1465,6 @@ chsc_get_chp_desc(struct subchannel *sch, int chp_no)
 	return desc;
 }
 
-static int reset_channel_path(struct channel_path *chp)
-{
-	int cc;
-
-	cc = rchp(chp->id);
-	switch (cc) {
-	case 0:
-		return 0;
-	case 2:
-		return -EBUSY;
-	default:
-		return -ENODEV;
-	}
-}
-
-static void reset_channel_paths_css(struct channel_subsystem *css)
-{
-	int i;
-
-	for (i = 0; i <= __MAX_CHPID; i++) {
-		if (css->chps[i])
-			reset_channel_path(css->chps[i]);
-	}
-}
-
-void cio_reset_channel_paths(void)
-{
-	int i;
-
-	for (i = 0; i <= __MAX_CSSID; i++) {
-		if (css[i] && css[i]->valid)
-			reset_channel_paths_css(css[i]);
-	}
-}
-
 static int __init
 chsc_alloc_sei_area(void)
 {