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powerpc/lib/code-patching: refactor patch_instruction() 

commit 8cf4c05712 upstream.

patch_instruction() uses almost the same sequence as
__patch_instruction()

This patch refactor it so that patch_instruction() uses
__patch_instruction() instead of duplicating code.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Acked-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
pull/10/head
Christophe Leroy 2017-11-24 08:31:07 +01:00 committed by Greg Kroah-Hartman
parent 0f6e2f4e06
commit 4e43fbc8ef
1 changed files with 15 additions and 15 deletions
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30
arch/powerpc/lib/code-patching.c
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@ -23,19 +23,26 @@
#include <asm/code-patching.h>
#include <asm/setup.h>
static int __patch_instruction(unsigned int *addr, unsigned int instr)
static int __patch_instruction(unsigned int *exec_addr, unsigned int instr,
unsigned int *patch_addr)
{
int err;
__put_user_size(instr, addr, 4, err);
__put_user_size(instr, patch_addr, 4, err);
if (err)
return err;
asm ("dcbst 0, %0; sync; icbi 0,%0; sync; isync" :: "r" (addr));
asm ("dcbst 0, %0; sync; icbi 0,%1; sync; isync" :: "r" (patch_addr),
"r" (exec_addr));
return 0;
}
static int raw_patch_instruction(unsigned int *addr, unsigned int instr)
{
return __patch_instruction(addr, instr, addr);
}
#ifdef CONFIG_STRICT_KERNEL_RWX
static DEFINE_PER_CPU(struct vm_struct *, text_poke_area);
@ -138,7 +145,7 @@ static inline int unmap_patch_area(unsigned long addr)
int patch_instruction(unsigned int *addr, unsigned int instr)
{
int err;
unsigned int *dest = NULL;
unsigned int *patch_addr = NULL;
unsigned long flags;
unsigned long text_poke_addr;
unsigned long kaddr = (unsigned long)addr;
@ -149,7 +156,7 @@ int patch_instruction(unsigned int *addr, unsigned int instr)
* to allow patching. We just do the plain old patching
*/
if (!this_cpu_read(*PTRRELOC(&text_poke_area)))
return __patch_instruction(addr, instr);
return raw_patch_instruction(addr, instr);
local_irq_save(flags);
@ -159,17 +166,10 @@ int patch_instruction(unsigned int *addr, unsigned int instr)
goto out;
}
dest = (unsigned int *)(text_poke_addr) +
patch_addr = (unsigned int *)(text_poke_addr) +
((kaddr & ~PAGE_MASK) / sizeof(unsigned int));
/*
* We use __put_user_size so that we can handle faults while
* writing to dest and return err to handle faults gracefully
*/
__put_user_size(instr, dest, 4, err);
if (!err)
asm ("dcbst 0, %0; sync; icbi 0,%0; icbi 0,%1; sync; isync"
::"r" (dest), "r"(addr));
__patch_instruction(addr, instr, patch_addr);
err = unmap_patch_area(text_poke_addr);
if (err)
@ -184,7 +184,7 @@ out:
int patch_instruction(unsigned int *addr, unsigned int instr)
{
return __patch_instruction(addr, instr);
return raw_patch_instruction(addr, instr);
}
#endif /* CONFIG_STRICT_KERNEL_RWX */