fedora core 6 1.2949 + vserver 2.2.0

[linux-2.6.git] / arch / arm / kernel / fiq.c

diff --git a/arch/arm/kernel/fiq.c b/arch/arm/kernel/fiq.c
index 6f79381..e8e9034 100644 (file)
--- a/arch/arm/kernel/fiq.c
+++ b/arch/arm/kernel/fiq.c
@@ -38,6 +38,7 @@
 #include <linux/module.h>
 #include <linux/kernel.h>
 #include <linux/init.h>
+#include <linux/interrupt.h>
 #include <linux/seq_file.h>
 
 #include <asm/cacheflush.h>
@@ -46,32 +47,16 @@
 #include <asm/system.h>
 #include <asm/uaccess.h>
 
-#define FIQ_VECTOR (vectors_base() + 0x1c)
-
 static unsigned long no_fiq_insn;
 
-static inline void unprotect_page_0(void)
-{
-       modify_domain(DOMAIN_USER, DOMAIN_MANAGER);
-}
-
-static inline void protect_page_0(void)
-{
-       modify_domain(DOMAIN_USER, DOMAIN_CLIENT);
-}
-
 /* Default reacquire function
  * - we always relinquish FIQ control
  * - we always reacquire FIQ control
  */
 static int fiq_def_op(void *ref, int relinquish)
 {
-       if (!relinquish) {
-               unprotect_page_0();
-               *(unsigned long *)FIQ_VECTOR = no_fiq_insn;
-               protect_page_0();
-               flush_icache_range(FIQ_VECTOR, FIQ_VECTOR + 4);
-       }
+       if (!relinquish)
+               set_fiq_handler(&no_fiq_insn, sizeof(no_fiq_insn));
 
        return 0;
 }
@@ -93,56 +78,51 @@ int show_fiq_list(struct seq_file *p, void *v)
 
 void set_fiq_handler(void *start, unsigned int length)
 {
-       unprotect_page_0();
-
-       memcpy((void *)FIQ_VECTOR, start, length);
-
-       protect_page_0();
-       flush_icache_range(FIQ_VECTOR, FIQ_VECTOR + length);
+       memcpy((void *)0xffff001c, start, length);
+       flush_icache_range(0xffff001c, 0xffff001c + length);
+       if (!vectors_high())
+               flush_icache_range(0x1c, 0x1c + length);
 }
 
 /*
  * Taking an interrupt in FIQ mode is death, so both these functions
- * disable irqs for the duration. 
+ * disable irqs for the duration.  Note - these functions are almost
+ * entirely coded in assembly.
  */
-void set_fiq_regs(struct pt_regs *regs)
+void __attribute__((naked)) set_fiq_regs(struct pt_regs *regs)
 {
-       register unsigned long tmp, tmp2;
-       __asm__ volatile (
-       "mrs    %0, cpsr\n\
-       mov     %1, %3\n\
-       msr     cpsr_c, %1      @ select FIQ mode\n\
+       register unsigned long tmp;
+       asm volatile (
+       "mov    ip, sp\n\
+       stmfd   sp!, {fp, ip, lr, pc}\n\
+       sub     fp, ip, #4\n\
+       mrs     %0, cpsr\n\
+       msr     cpsr_c, %2      @ select FIQ mode\n\
        mov     r0, r0\n\
-       ldmia   %2, {r8 - r14}\n\
+       ldmia   %1, {r8 - r14}\n\
        msr     cpsr_c, %0      @ return to SVC mode\n\
-       mov     r0, r0"
-       : "=&r" (tmp), "=&r" (tmp2)
-       : "r" (&regs->ARM_r8), "I" (PSR_I_BIT | PSR_F_BIT | FIQ_MODE)
-       /* These registers aren't modified by the above code in a way
-          visible to the compiler, but we mark them as clobbers anyway
-          so that GCC won't put any of the input or output operands in
-          them.  */
-       : "r8", "r9", "r10", "r11", "r12", "r13", "r14");
+       mov     r0, r0\n\
+       ldmfd   sp, {fp, sp, pc}"
+       : "=&r" (tmp)
+       : "r" (&regs->ARM_r8), "I" (PSR_I_BIT | PSR_F_BIT | FIQ_MODE));
 }
 
-void get_fiq_regs(struct pt_regs *regs)
+void __attribute__((naked)) get_fiq_regs(struct pt_regs *regs)
 {
-       register unsigned long tmp, tmp2;
-       __asm__ volatile (
-       "mrs    %0, cpsr\n\
-       mov     %1, %3\n\
-       msr     cpsr_c, %1      @ select FIQ mode\n\
+       register unsigned long tmp;
+       asm volatile (
+       "mov    ip, sp\n\
+       stmfd   sp!, {fp, ip, lr, pc}\n\
+       sub     fp, ip, #4\n\
+       mrs     %0, cpsr\n\
+       msr     cpsr_c, %2      @ select FIQ mode\n\
        mov     r0, r0\n\
-       stmia   %2, {r8 - r14}\n\
+       stmia   %1, {r8 - r14}\n\
        msr     cpsr_c, %0      @ return to SVC mode\n\
-       mov     r0, r0"
-       : "=&r" (tmp), "=&r" (tmp2)
-       : "r" (&regs->ARM_r8), "I" (PSR_I_BIT | PSR_F_BIT | FIQ_MODE)
-       /* These registers aren't modified by the above code in a way
-          visible to the compiler, but we mark them as clobbers anyway
-          so that GCC won't put any of the input or output operands in
-          them.  */
-       : "r8", "r9", "r10", "r11", "r12", "r13", "r14");
+       mov     r0, r0\n\
+       ldmfd   sp, {fp, sp, pc}"
+       : "=&r" (tmp)
+       : "r" (&regs->ARM_r8), "I" (PSR_I_BIT | PSR_F_BIT | FIQ_MODE));
 }
 
 int claim_fiq(struct fiq_handler *f)
@@ -198,6 +178,5 @@ EXPORT_SYMBOL(disable_fiq);
 
 void __init init_FIQ(void)
 {
-       no_fiq_insn = *(unsigned long *)FIQ_VECTOR;
-       set_fs(get_fs());
+       no_fiq_insn = *(unsigned long *)0xffff001c;
 }