Something went wrong. Try again.
Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Something went wrong. Try again.
1234567891011121314151617181920212223242526272829303132333435363738394041424344454647484950515253545556575859606162636465666768697071727374757677787980818283// SPDX-License-Identifier: GPL-2.0-only/* Copyright (C) 2020 SiFive * Copyright (C) 2025 Chen Miao */
#include <linux/mm.h>#include <linux/kernel.h>#include <linux/spinlock.h>#include <linux/uaccess.h>
#include <asm/insn-def.h>#include <asm/cacheflush.h>#include <asm/page.h>#include <asm/fixmap.h>#include <asm/text-patching.h>#include <asm/sections.h>
static DEFINE_RAW_SPINLOCK(patch_lock);
static __always_inline void *patch_map(void *addr, int fixmap){ uintptr_t uaddr = (uintptr_t) addr; phys_addr_t phys;
if (core_kernel_text(uaddr)) { phys = __pa_symbol(addr); } else { struct page *page = vmalloc_to_page(addr); BUG_ON(!page); phys = page_to_phys(page) + offset_in_page(addr); }
return (void *)set_fixmap_offset(fixmap, phys);}
static void patch_unmap(int fixmap){ clear_fixmap(fixmap);}
static int __patch_insn_write(void *addr, u32 insn){ void *waddr = addr; unsigned long flags = 0; int ret;
raw_spin_lock_irqsave(&patch_lock, flags);
waddr = patch_map(addr, FIX_TEXT_POKE0);
ret = copy_to_kernel_nofault(waddr, &insn, OPENRISC_INSN_SIZE); if (!IS_ENABLED(CONFIG_DCACHE_WRITETHROUGH)) local_dcache_range_flush((unsigned long)waddr, (unsigned long)waddr + OPENRISC_INSN_SIZE); local_icache_range_inv((unsigned long)waddr, (unsigned long)waddr + OPENRISC_INSN_SIZE);
patch_unmap(FIX_TEXT_POKE0);
raw_spin_unlock_irqrestore(&patch_lock, flags);
return ret;}
/* * patch_insn_write - Write a single instruction to a specified memory location * This API provides a single-instruction patching, primarily used for runtime * code modification. * By the way, the insn size must be 4 bytes. */int patch_insn_write(void *addr, u32 insn){ u32 *tp = addr; int ret;
if ((uintptr_t) tp & 0x3) return -EINVAL;
ret = __patch_insn_write(tp, insn);
return ret;}