Commit 6b21af74 authored by Christophe Leroy's avatar Christophe Leroy Committed by Michael Ellerman
Browse files

powerpc/code-patching: Reorganise do_patch_instruction() to ease error handling 



Split do_patch_instruction() in two functions, the caller doing the
spin locking and the callee doing everything else.

And remove a few unnecessary initialisations and intermediate
variables.

This allows the callee to return from anywhere in the function.

Signed-off-by: default avatarChristophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/dbc85980a0d2a935731b272e8907e8bb1d8fc8c5.1638446239.git.christophe.leroy@csgroup.eu
parent a3483c3d

arch/powerpc/lib/code-patching.c

+21 −16
Original line number Diff line number Diff line
@@ -129,13 +129,30 @@ static void unmap_patch_area(unsigned long addr) 
	flush_tlb_kernel_range(addr, addr + PAGE_SIZE);

}



static int __do_patch_instruction(u32 *addr, ppc_inst_t instr)

{

	int err;

	u32 *patch_addr;

	unsigned long text_poke_addr;



	text_poke_addr = (unsigned long)__this_cpu_read(text_poke_area)->addr;

	patch_addr = (u32 *)(text_poke_addr + offset_in_page(addr));



	err = map_patch_area(addr, text_poke_addr);

	if (err)

		return err;



	err = __patch_instruction(addr, instr, patch_addr);



	unmap_patch_area(text_poke_addr);



	return err;

}



static int do_patch_instruction(u32 *addr, ppc_inst_t instr)

{

	int err;

	u32 *patch_addr = NULL;

	unsigned long flags;

	unsigned long text_poke_addr;

	unsigned long kaddr = (unsigned long)addr;



	/*

	 * During early early boot patch_instruction is called
@@ -146,19 +163,7 @@ static int do_patch_instruction(u32 *addr, ppc_inst_t instr) 
		return raw_patch_instruction(addr, instr);



	local_irq_save(flags);



	text_poke_addr = (unsigned long)__this_cpu_read(text_poke_area)->addr;

	err = map_patch_area(addr, text_poke_addr);

	if (err)

		goto out;



	patch_addr = (u32 *)(text_poke_addr + (kaddr & ~PAGE_MASK));



	err = __patch_instruction(addr, instr, patch_addr);



	unmap_patch_area(text_poke_addr);



out:

	err = __do_patch_instruction(addr, instr);

	local_irq_restore(flags);



	return err;