Merge to Fedora kernel-2.6.18-1.2224_FC5 patched with stable patch-2.6.18.1-vs2.0...

[linux-2.6.git] / arch / s390 / kernel / s390_ext.c

diff --git a/arch/s390/kernel/s390_ext.c b/arch/s390/kernel/s390_ext.c
index c00e5e3..6f5bafb 100644 (file)
--- a/arch/s390/kernel/s390_ext.c
+++ b/arch/s390/kernel/s390_ext.c
@@ -12,19 +12,25 @@
 #include <linux/slab.h>
 #include <linux/errno.h>
 #include <linux/kernel_stat.h>
+#include <linux/interrupt.h>
+#include <linux/vs_context.h>
 
 #include <asm/lowcore.h>
 #include <asm/s390_ext.h>
 #include <asm/irq.h>
 
 /*
- * Simple hash strategy: index = code & 0xff;
  * ext_int_hash[index] is the start of the list for all external interrupts
  * that hash to this index. With the current set of external interrupts 
  * (0x1202 external call, 0x1004 cpu timer, 0x2401 hwc console, 0x4000
  * iucv and 0x2603 pfault) this is always the first element. 
  */
-ext_int_info_t *ext_int_hash[256] = { 0, };
+ext_int_info_t *ext_int_hash[256] = { NULL, };
+
+static inline int ext_hash(__u16 code)
+{
+       return (code + (code >> 9)) & 0xff;
+}
 
 int register_external_interrupt(__u16 code, ext_int_handler_t handler)
 {
@@ -36,7 +42,7 @@ int register_external_interrupt(__u16 code, ext_int_handler_t handler)
                 return -ENOMEM;
         p->code = code;
         p->handler = handler;
-        index = code & 0xff;
+       index = ext_hash(code);
         p->next = ext_int_hash[index];
         ext_int_hash[index] = p;
         return 0;
@@ -51,7 +57,7 @@ int register_early_external_interrupt(__u16 code, ext_int_handler_t handler,
                 return -EINVAL;
         p->code = code;
         p->handler = handler;
-        index = code & 0xff;
+       index = ext_hash(code);
         p->next = ext_int_hash[index];
         ext_int_hash[index] = p;
         return 0;
@@ -62,7 +68,7 @@ int unregister_external_interrupt(__u16 code, ext_int_handler_t handler)
         ext_int_info_t *p, *q;
         int index;
 
-        index = code & 0xff;
+       index = ext_hash(code);
         q = NULL;
         p = ext_int_hash[index];
         while (p != NULL) {
@@ -89,7 +95,7 @@ int unregister_early_external_interrupt(__u16 code, ext_int_handler_t handler,
 
        if (p == NULL || p->code != code || p->handler != handler)
                return -EINVAL;
-       index = code & 0xff;
+       index = ext_hash(code);
        q = ext_int_hash[index];
        if (p != q) {
                while (q != NULL) {
@@ -108,20 +114,27 @@ int unregister_early_external_interrupt(__u16 code, ext_int_handler_t handler,
 void do_extint(struct pt_regs *regs, unsigned short code)
 {
         ext_int_info_t *p;
+       struct vx_info_save vxis;
         int index;
 
        irq_enter();
        asm volatile ("mc 0,0");
        if (S390_lowcore.int_clock >= S390_lowcore.jiffy_timer)
+               /**
+                * Make sure that the i/o interrupt did not "overtake"
+                * the last HZ timer interrupt.
+                */
                account_ticks(regs);
        kstat_cpu(smp_processor_id()).irqs[EXTERNAL_INTERRUPT]++;
-        index = code & 0xff;
+        index = ext_hash(code);
+       __enter_vx_admin(&vxis);
        for (p = ext_int_hash[index]; p; p = p->next) {
                if (likely(p->code == code)) {
                        if (likely(p->handler))
                                p->handler(regs, code);
                }
        }
+       __leave_vx_admin(&vxis);
        irq_exit();
 }