linux-kernel - [PATCH v2 6/7] riscv: Use offset_in_page() in text patching functions

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Date: Wed, 27 Mar 2024 09:04:45 -0700
From: Samuel Holland <samuel.holland@...ive.com>
To: Palmer Dabbelt <palmer@...belt.com>
Cc: Björn Töpel <bjorn@...osinc.com>,
	linux-riscv@...ts.infradead.org,
	linux-kernel@...r.kernel.org,
	Samuel Holland <samuel.holland@...ive.com>
Subject: [PATCH v2 6/7] riscv: Use offset_in_page() in text patching functions

This is a bit easier to parse than the equivalent bit manipulation.

Reviewed-by: Björn Töpel <bjorn@...osinc.com>
Signed-off-by: Samuel Holland <samuel.holland@...ive.com>
---

(no changes since v1)

 arch/riscv/kernel/patch.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/arch/riscv/kernel/patch.c b/arch/riscv/kernel/patch.c
index 243e1573410b..cfcb9926e722 100644
--- a/arch/riscv/kernel/patch.c
+++ b/arch/riscv/kernel/patch.c
@@ -54,7 +54,7 @@ static __always_inline void *patch_map(void *addr, const unsigned int fixmap)
 	BUG_ON(!page);
 
 	return (void *)set_fixmap_offset(fixmap, page_to_phys(page) +
-					 (uintaddr & ~PAGE_MASK));
+					 offset_in_page(addr));
 }
 
 static void patch_unmap(int fixmap)
@@ -65,8 +65,8 @@ NOKPROBE_SYMBOL(patch_unmap);
 
 static int __patch_insn_set(void *addr, u8 c, size_t len)
 {
+	bool across_pages = (offset_in_page(addr) + len) > PAGE_SIZE;
 	void *waddr = addr;
-	bool across_pages = (((uintptr_t)addr & ~PAGE_MASK) + len) > PAGE_SIZE;
 
 	/*
 	 * Only two pages can be mapped at a time for writing.
@@ -98,8 +98,8 @@ NOKPROBE_SYMBOL(__patch_insn_set);
 
 static int __patch_insn_write(void *addr, const void *insn, size_t len)
 {
+	bool across_pages = (offset_in_page(addr) + len) > PAGE_SIZE;
 	void *waddr = addr;
-	bool across_pages = (((uintptr_t) addr & ~PAGE_MASK) + len) > PAGE_SIZE;
 	int ret;
 
 	/*
-- 
2.43.1