x86/kexec: Merge x86_32 and x86_64 code using macros from <asm/asm.h>

Merge common x86_32 and x86_64 code in crash_setup_regs()
using macros from <asm/asm.h>.

The compiled object files before and after the patch are unchanged.

Signed-off-by: Uros Bizjak <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
Cc: David Woodhouse <[email protected]>
Cc: Baoquan He <[email protected]>
Cc: Vivek Goyal <[email protected]>
Cc: Dave Young <[email protected]>
Cc: Ard Biesheuvel <[email protected]>
Cc: "H. Peter Anvin" <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

Author: ubizjak

arch/x86/include/asm/kexec.h

@@ -18,6 +18,7 @@
 #include <linux/string.h>
 #include <linux/kernel.h>
 
+#include <asm/asm.h>
 #include <asm/page.h>
 #include <asm/ptrace.h>
 
@@ -71,41 +72,32 @@ static inline void crash_setup_regs(struct pt_regs *newregs,
 	if (oldregs) {
 		memcpy(newregs, oldregs, sizeof(*newregs));
 	} else {
+		asm volatile("mov %%" _ASM_BX ",%0" : "=m"(newregs->bx));
+		asm volatile("mov %%" _ASM_CX ",%0" : "=m"(newregs->cx));
+		asm volatile("mov %%" _ASM_DX ",%0" : "=m"(newregs->dx));
+		asm volatile("mov %%" _ASM_SI ",%0" : "=m"(newregs->si));
+		asm volatile("mov %%" _ASM_DI ",%0" : "=m"(newregs->di));
+		asm volatile("mov %%" _ASM_BP ",%0" : "=m"(newregs->bp));
+		asm volatile("mov %%" _ASM_AX ",%0" : "=m"(newregs->ax));
+		asm volatile("mov %%" _ASM_SP ",%0" : "=m"(newregs->sp));
+#ifdef CONFIG_X86_64
+		asm volatile("mov %%r8,%0" : "=m"(newregs->r8));
+		asm volatile("mov %%r9,%0" : "=m"(newregs->r9));
+		asm volatile("mov %%r10,%0" : "=m"(newregs->r10));
+		asm volatile("mov %%r11,%0" : "=m"(newregs->r11));
+		asm volatile("mov %%r12,%0" : "=m"(newregs->r12));
+		asm volatile("mov %%r13,%0" : "=m"(newregs->r13));
+		asm volatile("mov %%r14,%0" : "=m"(newregs->r14));
+		asm volatile("mov %%r15,%0" : "=m"(newregs->r15));
+#endif
+		asm volatile("mov %%ss,%k0" : "=a"(newregs->ss));
+		asm volatile("mov %%cs,%k0" : "=a"(newregs->cs));
 #ifdef CONFIG_X86_32
-		asm volatile("movl %%ebx,%0" : "=m"(newregs->bx));
-		asm volatile("movl %%ecx,%0" : "=m"(newregs->cx));
-		asm volatile("movl %%edx,%0" : "=m"(newregs->dx));
-		asm volatile("movl %%esi,%0" : "=m"(newregs->si));
-		asm volatile("movl %%edi,%0" : "=m"(newregs->di));
-		asm volatile("movl %%ebp,%0" : "=m"(newregs->bp));
-		asm volatile("movl %%eax,%0" : "=m"(newregs->ax));
-		asm volatile("movl %%esp,%0" : "=m"(newregs->sp));
-		asm volatile("movl %%ss, %%eax;" :"=a"(newregs->ss));
-		asm volatile("movl %%cs, %%eax;" :"=a"(newregs->cs));
-		asm volatile("movl %%ds, %%eax;" :"=a"(newregs->ds));
-		asm volatile("movl %%es, %%eax;" :"=a"(newregs->es));
-		asm volatile("pushfl; popl %0" :"=m"(newregs->flags));
-#else
-		asm volatile("movq %%rbx,%0" : "=m"(newregs->bx));
-		asm volatile("movq %%rcx,%0" : "=m"(newregs->cx));
-		asm volatile("movq %%rdx,%0" : "=m"(newregs->dx));
-		asm volatile("movq %%rsi,%0" : "=m"(newregs->si));
-		asm volatile("movq %%rdi,%0" : "=m"(newregs->di));
-		asm volatile("movq %%rbp,%0" : "=m"(newregs->bp));
-		asm volatile("movq %%rax,%0" : "=m"(newregs->ax));
-		asm volatile("movq %%rsp,%0" : "=m"(newregs->sp));
-		asm volatile("movq %%r8,%0" : "=m"(newregs->r8));
-		asm volatile("movq %%r9,%0" : "=m"(newregs->r9));
-		asm volatile("movq %%r10,%0" : "=m"(newregs->r10));
-		asm volatile("movq %%r11,%0" : "=m"(newregs->r11));
-		asm volatile("movq %%r12,%0" : "=m"(newregs->r12));
-		asm volatile("movq %%r13,%0" : "=m"(newregs->r13));
-		asm volatile("movq %%r14,%0" : "=m"(newregs->r14));
-		asm volatile("movq %%r15,%0" : "=m"(newregs->r15));
-		asm volatile("movl %%ss, %%eax;" :"=a"(newregs->ss));
-		asm volatile("movl %%cs, %%eax;" :"=a"(newregs->cs));
-		asm volatile("pushfq; popq %0" :"=m"(newregs->flags));
+		asm volatile("mov %%ds,%k0" : "=a"(newregs->ds));
+		asm volatile("mov %%es,%k0" : "=a"(newregs->es));
 #endif
+		asm volatile("pushf\n\t"
+			     "pop %0" : "=m"(newregs->flags));
 		newregs->ip = _THIS_IP_;
 	}
 }