Unverified Commit 5080ca0f authored by Samuel Holland's avatar Samuel Holland Committed by Palmer Dabbelt
Browse files

riscv: Simplify text patching loops 



This reduces the number of variables and makes the code easier to parse.

Signed-off-by: default avatarSamuel Holland <samuel.holland@sifive.com>
Reviewed-by: default avatarBjörn Töpel <bjorn@rivosinc.com>
Reviewed-by: default avatarConor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20240327160520.791322-5-samuel.holland@sifive.com


Signed-off-by: default avatarPalmer Dabbelt <palmer@rivosinc.com>
parent b1756750

arch/riscv/kernel/patch.c

+21 −16
Original line number Diff line number Diff line
@@ -163,22 +163,24 @@ NOKPROBE_SYMBOL(__patch_insn_write); 


static int patch_insn_set(void *addr, u8 c, size_t len)

{

	size_t patched = 0;

	size_t size;

	int ret = 0;

	int ret;



	/*

	 * __patch_insn_set() can only work on 2 pages at a time so call it in a

	 * loop with len <= 2 * PAGE_SIZE.

	 */

	while (patched < len && !ret) {

		size = min_t(size_t, PAGE_SIZE * 2 - offset_in_page(addr + patched), len - patched);

		ret = __patch_insn_set(addr + patched, c, size);

	while (len) {

		size = min(len, PAGE_SIZE * 2 - offset_in_page(addr));

		ret = __patch_insn_set(addr, c, size);

		if (ret)

			return ret;



		patched += size;

		addr += size;

		len -= size;

	}



	return ret;

	return 0;

}

NOKPROBE_SYMBOL(patch_insn_set);
@@ -198,22 +200,25 @@ NOKPROBE_SYMBOL(patch_text_set_nosync); 


int patch_insn_write(void *addr, const void *insn, size_t len)

{

	size_t patched = 0;

	size_t size;

	int ret = 0;

	int ret;



	/*

	 * Copy the instructions to the destination address, two pages at a time

	 * because __patch_insn_write() can only handle len <= 2 * PAGE_SIZE.

	 */

	while (patched < len && !ret) {

		size = min_t(size_t, PAGE_SIZE * 2 - offset_in_page(addr + patched), len - patched);

		ret = __patch_insn_write(addr + patched, insn + patched, size);

	while (len) {

		size = min(len, PAGE_SIZE * 2 - offset_in_page(addr));

		ret = __patch_insn_write(addr, insn, size);

		if (ret)

			return ret;



		patched += size;

		addr += size;

		insn += size;

		len -= size;

	}



	return ret;

	return 0;

}

NOKPROBE_SYMBOL(patch_insn_write);