X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=arch%2Fs390%2Fmm%2Ffault.c;fp=arch%2Fs390%2Fmm%2Ffault.c;h=1c59d40a496704243c6cef7b42a5bc4433e25466;hb=97bf2856c6014879bd04983a3e9dfcdac1e7fe85;hp=81ade401b073bfe62627c9a946de3ac3b04e0483;hpb=76828883507a47dae78837ab5dec5a5b4513c667;p=linux-2.6.git

diff --git a/arch/s390/mm/fault.c b/arch/s390/mm/fault.c
index 81ade401b..1c59d40a4 100644
--- a/arch/s390/mm/fault.c
+++ b/arch/s390/mm/fault.c
@@ -10,7 +10,6 @@
  *    Copyright (C) 1995  Linus Torvalds
  */
 
-#include <linux/config.h>
 #include <linux/signal.h>
 #include <linux/sched.h>
 #include <linux/kernel.h>
@@ -26,10 +25,13 @@
 #include <linux/console.h>
 #include <linux/module.h>
 #include <linux/hardirq.h>
+#include <linux/kprobes.h>
 
 #include <asm/system.h>
 #include <asm/uaccess.h>
 #include <asm/pgtable.h>
+#include <asm/kdebug.h>
+#include <asm/s390_ext.h>
 
 #ifndef CONFIG_64BIT
 #define __FAIL_ADDR_MASK 0x7ffff000
@@ -49,6 +51,38 @@ extern int sysctl_userprocess_debug;
 
 extern void die(const char *,struct pt_regs *,long);
 
+#ifdef CONFIG_KPROBES
+ATOMIC_NOTIFIER_HEAD(notify_page_fault_chain);
+int register_page_fault_notifier(struct notifier_block *nb)
+{
+	return atomic_notifier_chain_register(&notify_page_fault_chain, nb);
+}
+
+int unregister_page_fault_notifier(struct notifier_block *nb)
+{
+	return atomic_notifier_chain_unregister(&notify_page_fault_chain, nb);
+}
+
+static inline int notify_page_fault(enum die_val val, const char *str,
+			struct pt_regs *regs, long err, int trap, int sig)
+{
+	struct die_args args = {
+		.regs = regs,
+		.str = str,
+		.err = err,
+		.trapnr = trap,
+		.signr = sig
+	};
+	return atomic_notifier_call_chain(&notify_page_fault_chain, val, &args);
+}
+#else
+static inline int notify_page_fault(enum die_val val, const char *str,
+			struct pt_regs *regs, long err, int trap, int sig)
+{
+	return NOTIFY_DONE;
+}
+#endif
+
 extern spinlock_t timerlist_lock;
 
 /*
@@ -145,7 +179,7 @@ static void do_sigsegv(struct pt_regs *regs, unsigned long error_code,
 #endif
 	si.si_signo = SIGSEGV;
 	si.si_code = si_code;
-	si.si_addr = (void *) address;
+	si.si_addr = (void __user *) address;
 	force_sig_info(SIGSEGV, &si, current);
 }
 
@@ -160,7 +194,7 @@ static void do_sigsegv(struct pt_regs *regs, unsigned long error_code,
  *   11       Page translation     ->  Not present       (nullification)
  *   3b       Region third trans.  ->  Not present       (nullification)
  */
-static inline void
+static inline void __kprobes
 do_exception(struct pt_regs *regs, unsigned long error_code, int is_protection)
 {
         struct task_struct *tsk;
@@ -174,6 +208,10 @@ do_exception(struct pt_regs *regs, unsigned long error_code, int is_protection)
         tsk = current;
         mm = tsk->mm;
 	
+	if (notify_page_fault(DIE_PAGE_FAULT, "page fault", regs, error_code, 14,
+					SIGSEGV) == NOTIFY_STOP)
+		return;
+
 	/* 
          * Check for low-address protection.  This needs to be treated
 	 * as a special case because the translation exception code 
@@ -316,11 +354,13 @@ no_context:
 */
 out_of_memory:
 	up_read(&mm->mmap_sem);
-	if (tsk->pid == 1) {
+	if (is_init(tsk)) {
 		yield();
+		down_read(&mm->mmap_sem);
 		goto survive;
 	}
-	printk("VM: killing process %s\n", tsk->comm);
+	printk("VM: killing process %s(%d:#%u)\n",
+		tsk->comm, tsk->pid, tsk->xid);
 	if (regs->psw.mask & PSW_MASK_PSTATE)
 		do_exit(SIGKILL);
 	goto no_context;
@@ -356,6 +396,7 @@ void do_dat_exception(struct pt_regs *regs, unsigned long error_code)
 /*
  * 'pfault' pseudo page faults routines.
  */
+static ext_int_info_t ext_int_pfault;
 static int pfault_disable = 0;
 
 static int __init nopfault(char *str)
@@ -384,22 +425,15 @@ int pfault_init(void)
 		  __PF_RES_FIELD };
         int rc;
 
-	if (pfault_disable)
+	if (!MACHINE_IS_VM || pfault_disable)
 		return -1;
-        __asm__ __volatile__(
-                "    diag  %1,%0,0x258\n"
-		"0:  j     2f\n"
-		"1:  la    %0,8\n"
+	asm volatile(
+		"	diag	%1,%0,0x258\n"
+		"0:	j	2f\n"
+		"1:	la	%0,8\n"
 		"2:\n"
-		".section __ex_table,\"a\"\n"
-		"   .align 4\n"
-#ifndef CONFIG_64BIT
-		"   .long  0b,1b\n"
-#else /* CONFIG_64BIT */
-		"   .quad  0b,1b\n"
-#endif /* CONFIG_64BIT */
-		".previous"
-                : "=d" (rc) : "a" (&refbk), "m" (refbk) : "cc" );
+		EX_TABLE(0b,1b)
+		: "=d" (rc) : "a" (&refbk), "m" (refbk) : "cc");
         __ctl_set_bit(0, 9);
         return rc;
 }
@@ -409,25 +443,18 @@ void pfault_fini(void)
 	pfault_refbk_t refbk =
 	{ 0x258, 1, 5, 2, 0ULL, 0ULL, 0ULL, 0ULL };
 
-	if (pfault_disable)
+	if (!MACHINE_IS_VM || pfault_disable)
 		return;
 	__ctl_clear_bit(0,9);
-        __asm__ __volatile__(
-                "    diag  %0,0,0x258\n"
+	asm volatile(
+		"	diag	%0,0,0x258\n"
 		"0:\n"
-		".section __ex_table,\"a\"\n"
-		"   .align 4\n"
-#ifndef CONFIG_64BIT
-		"   .long  0b,0b\n"
-#else /* CONFIG_64BIT */
-		"   .quad  0b,0b\n"
-#endif /* CONFIG_64BIT */
-		".previous"
-		: : "a" (&refbk), "m" (refbk) : "cc" );
+		EX_TABLE(0b,0b)
+		: : "a" (&refbk), "m" (refbk) : "cc");
 }
 
 asmlinkage void
-pfault_interrupt(struct pt_regs *regs, __u16 error_code)
+pfault_interrupt(__u16 error_code)
 {
 	struct task_struct *tsk;
 	__u16 subcode;
@@ -476,5 +503,25 @@ pfault_interrupt(struct pt_regs *regs, __u16 error_code)
 			set_tsk_need_resched(tsk);
 	}
 }
-#endif
 
+void __init pfault_irq_init(void)
+{
+	if (!MACHINE_IS_VM)
+		return;
+
+	/*
+	 * Try to get pfault pseudo page faults going.
+	 */
+	if (register_early_external_interrupt(0x2603, pfault_interrupt,
+					      &ext_int_pfault) != 0)
+		panic("Couldn't request external interrupt 0x2603");
+
+	if (pfault_init() == 0)
+		return;
+
+	/* Tough luck, no pfault. */
+	pfault_disable = 1;
+	unregister_early_external_interrupt(0x2603, pfault_interrupt,
+					    &ext_int_pfault);
+}
+#endif