diff options
Diffstat (limited to 'arch/parisc/kernel/patch.c')
-rw-r--r-- | arch/parisc/kernel/patch.c | 88 |
1 files changed, 72 insertions, 16 deletions
diff --git a/arch/parisc/kernel/patch.c b/arch/parisc/kernel/patch.c index cdcd981278b3..80a0ab372802 100644 --- a/arch/parisc/kernel/patch.c +++ b/arch/parisc/kernel/patch.c @@ -17,15 +17,20 @@ struct patch { void *addr; - unsigned int insn; + u32 *insn; + unsigned int len; }; -static void __kprobes *patch_map(void *addr, int fixmap) +static DEFINE_RAW_SPINLOCK(patch_lock); + +static void __kprobes *patch_map(void *addr, int fixmap, unsigned long *flags, + int *need_unmap) { unsigned long uintaddr = (uintptr_t) addr; bool module = !core_kernel_text(uintaddr); struct page *page; + *need_unmap = 0; if (module && IS_ENABLED(CONFIG_STRICT_MODULE_RWX)) page = vmalloc_to_page(addr); else if (!module && IS_ENABLED(CONFIG_STRICT_KERNEL_RWX)) @@ -33,36 +38,74 @@ static void __kprobes *patch_map(void *addr, int fixmap) else return addr; + *need_unmap = 1; set_fixmap(fixmap, page_to_phys(page)); + if (flags) + raw_spin_lock_irqsave(&patch_lock, *flags); + else + __acquire(&patch_lock); return (void *) (__fix_to_virt(fixmap) + (uintaddr & ~PAGE_MASK)); } -static void __kprobes patch_unmap(int fixmap) +static void __kprobes patch_unmap(int fixmap, unsigned long *flags) { clear_fixmap(fixmap); + + if (flags) + raw_spin_unlock_irqrestore(&patch_lock, *flags); + else + __release(&patch_lock); +} + +void __kprobes __patch_text_multiple(void *addr, u32 *insn, unsigned int len) +{ + unsigned long start = (unsigned long)addr; + unsigned long end = (unsigned long)addr + len; + unsigned long flags; + u32 *p, *fixmap; + int mapped; + + /* Make sure we don't have any aliases in cache */ + flush_kernel_vmap_range(addr, len); + flush_icache_range(start, end); + + p = fixmap = patch_map(addr, FIX_TEXT_POKE0, &flags, &mapped); + + while (len >= 4) { + *p++ = *insn++; + addr += sizeof(u32); + len -= sizeof(u32); + if (len && offset_in_page(addr) == 0) { + /* + * We're crossing a page boundary, so + * need to remap + */ + flush_kernel_vmap_range((void *)fixmap, + (p-fixmap) * sizeof(*p)); + if (mapped) + patch_unmap(FIX_TEXT_POKE0, &flags); + p = fixmap = patch_map(addr, FIX_TEXT_POKE0, &flags, + &mapped); + } + } + + flush_kernel_vmap_range((void *)fixmap, (p-fixmap) * sizeof(*p)); + if (mapped) + patch_unmap(FIX_TEXT_POKE0, &flags); + flush_icache_range(start, end); } -void __kprobes __patch_text(void *addr, unsigned int insn) +void __kprobes __patch_text(void *addr, u32 insn) { - void *waddr = addr; - int size; - - waddr = patch_map(addr, FIX_TEXT_POKE0); - *(u32 *)waddr = insn; - size = sizeof(u32); - flush_kernel_vmap_range(waddr, size); - patch_unmap(FIX_TEXT_POKE0); - flush_icache_range((uintptr_t)(addr), - (uintptr_t)(addr) + size); + __patch_text_multiple(addr, &insn, sizeof(insn)); } static int __kprobes patch_text_stop_machine(void *data) { struct patch *patch = data; - __patch_text(patch->addr, patch->insn); - + __patch_text_multiple(patch->addr, patch->insn, patch->len); return 0; } @@ -70,7 +113,20 @@ void __kprobes patch_text(void *addr, unsigned int insn) { struct patch patch = { .addr = addr, + .insn = &insn, + .len = sizeof(insn), + }; + + stop_machine_cpuslocked(patch_text_stop_machine, &patch, NULL); +} + +void __kprobes patch_text_multiple(void *addr, u32 *insn, unsigned int len) +{ + + struct patch patch = { + .addr = addr, .insn = insn, + .len = len }; stop_machine_cpuslocked(patch_text_stop_machine, &patch, NULL); |