diff options
Diffstat (limited to 'arch/arm64')
| -rw-r--r-- | arch/arm64/Kconfig | 1 | ||||
| -rw-r--r-- | arch/arm64/include/asm/jump_label.h | 52 | ||||
| -rw-r--r-- | arch/arm64/kernel/Makefile | 1 | ||||
| -rw-r--r-- | arch/arm64/kernel/jump_label.c | 58 |
4 files changed, 112 insertions, 0 deletions
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 249acb9da4e..dd4327f09ba 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -25,6 +25,7 @@ config ARM64 select GENERIC_STRNLEN_USER select GENERIC_TIME_VSYSCALL select HARDIRQS_SW_RESEND + select HAVE_ARCH_JUMP_LABEL select HAVE_ARCH_TRACEHOOK select HAVE_DEBUG_BUGVERBOSE select HAVE_DEBUG_KMEMLEAK diff --git a/arch/arm64/include/asm/jump_label.h b/arch/arm64/include/asm/jump_label.h new file mode 100644 index 00000000000..076a1c71404 --- /dev/null +++ b/arch/arm64/include/asm/jump_label.h @@ -0,0 +1,52 @@ +/* + * Copyright (C) 2013 Huawei Ltd. + * Author: Jiang Liu <liuj97@gmail.com> + * + * Based on arch/arm/include/asm/jump_label.h + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ +#ifndef __ASM_JUMP_LABEL_H +#define __ASM_JUMP_LABEL_H +#include <linux/types.h> +#include <asm/insn.h> + +#ifdef __KERNEL__ + +#define JUMP_LABEL_NOP_SIZE AARCH64_INSN_SIZE + +static __always_inline bool arch_static_branch(struct static_key *key) +{ + asm goto("1: nop\n\t" + ".pushsection __jump_table, \"aw\"\n\t" + ".align 3\n\t" + ".quad 1b, %l[l_yes], %c0\n\t" + ".popsection\n\t" + : : "i"(key) : : l_yes); + + return false; +l_yes: + return true; +} + +#endif /* __KERNEL__ */ + +typedef u64 jump_label_t; + +struct jump_entry { + jump_label_t code; + jump_label_t target; + jump_label_t key; +}; + +#endif /* __ASM_JUMP_LABEL_H */ diff --git a/arch/arm64/kernel/Makefile b/arch/arm64/kernel/Makefile index 1ea7221f885..2d4554b1341 100644 --- a/arch/arm64/kernel/Makefile +++ b/arch/arm64/kernel/Makefile @@ -19,6 +19,7 @@ arm64-obj-$(CONFIG_HW_PERF_EVENTS) += perf_event.o arm64-obj-$(CONFIG_HAVE_HW_BREAKPOINT)+= hw_breakpoint.o arm64-obj-$(CONFIG_EARLY_PRINTK) += early_printk.o arm64-obj-$(CONFIG_ARM64_CPU_SUSPEND) += sleep.o suspend.o +arm64-obj-$(CONFIG_JUMP_LABEL) += jump_label.o obj-y += $(arm64-obj-y) vdso/ obj-m += $(arm64-obj-m) diff --git a/arch/arm64/kernel/jump_label.c b/arch/arm64/kernel/jump_label.c new file mode 100644 index 00000000000..263a166291f --- /dev/null +++ b/arch/arm64/kernel/jump_label.c @@ -0,0 +1,58 @@ +/* + * Copyright (C) 2013 Huawei Ltd. + * Author: Jiang Liu <liuj97@gmail.com> + * + * Based on arch/arm/kernel/jump_label.c + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ +#include <linux/kernel.h> +#include <linux/jump_label.h> +#include <asm/insn.h> + +#ifdef HAVE_JUMP_LABEL + +static void __arch_jump_label_transform(struct jump_entry *entry, + enum jump_label_type type, + bool is_static) +{ + void *addr = (void *)entry->code; + u32 insn; + + if (type == JUMP_LABEL_ENABLE) { + insn = aarch64_insn_gen_branch_imm(entry->code, + entry->target, + AARCH64_INSN_BRANCH_NOLINK); + } else { + insn = aarch64_insn_gen_nop(); + } + + if (is_static) + aarch64_insn_patch_text_nosync(addr, insn); + else + aarch64_insn_patch_text(&addr, &insn, 1); +} + +void arch_jump_label_transform(struct jump_entry *entry, + enum jump_label_type type) +{ + __arch_jump_label_transform(entry, type, false); +} + +void arch_jump_label_transform_static(struct jump_entry *entry, + enum jump_label_type type) +{ + __arch_jump_label_transform(entry, type, true); +} + +#endif /* HAVE_JUMP_LABEL */ |