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Diffstat (limited to 'arch/powerpc/lib/code-patching.c')
-rw-r--r--arch/powerpc/lib/code-patching.c37
1 files changed, 21 insertions, 16 deletions
diff --git a/arch/powerpc/lib/code-patching.c b/arch/powerpc/lib/code-patching.c
index d469224c4ada..e0d881ab304e 100644
--- a/arch/powerpc/lib/code-patching.c
+++ b/arch/powerpc/lib/code-patching.c
@@ -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;
}
+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;
@@ -148,8 +155,8 @@ int patch_instruction(unsigned int *addr, unsigned int instr)
* when text_poke_area is not ready, but we still need
* to allow patching. We just do the plain old patching
*/
- if (!this_cpu_read(*PTRRELOC(&text_poke_area)))
- return __patch_instruction(addr, instr);
+ if (!this_cpu_read(text_poke_area))
+ 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 */
@@ -302,6 +302,11 @@ int instr_is_relative_branch(unsigned int instr)
return instr_is_branch_iform(instr) || instr_is_branch_bform(instr);
}
+int instr_is_relative_link_branch(unsigned int instr)
+{
+ return instr_is_relative_branch(instr) && (instr & BRANCH_SET_LINK);
+}
+
static unsigned long branch_iform_target(const unsigned int *instr)
{
signed long imm;