diff options
| -rw-r--r-- | arch/csky/Kconfig | 2 | ||||
| -rw-r--r-- | arch/csky/include/asm/jump_label.h | 47 | ||||
| -rw-r--r-- | arch/csky/kernel/Makefile | 1 | ||||
| -rw-r--r-- | arch/csky/kernel/jump_label.c | 54 |
4 files changed, 104 insertions, 0 deletions
diff --git a/arch/csky/Kconfig b/arch/csky/Kconfig index 21d72b078eef..41d7d614f7a2 100644 --- a/arch/csky/Kconfig +++ b/arch/csky/Kconfig @@ -40,6 +40,8 @@ config CSKY select GX6605S_TIMER if CPU_CK610 select HAVE_ARCH_TRACEHOOK select HAVE_ARCH_AUDITSYSCALL + select HAVE_ARCH_JUMP_LABEL if !CPU_CK610 + select HAVE_ARCH_JUMP_LABEL_RELATIVE select HAVE_ARCH_MMAP_RND_BITS select HAVE_ARCH_SECCOMP_FILTER select HAVE_CONTEXT_TRACKING diff --git a/arch/csky/include/asm/jump_label.h b/arch/csky/include/asm/jump_label.h new file mode 100644 index 000000000000..d488ba6084bc --- /dev/null +++ b/arch/csky/include/asm/jump_label.h @@ -0,0 +1,47 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ + +#ifndef __ASM_CSKY_JUMP_LABEL_H +#define __ASM_CSKY_JUMP_LABEL_H + +#ifndef __ASSEMBLY__ + +#include <linux/types.h> + +#define JUMP_LABEL_NOP_SIZE 4 + +static __always_inline bool arch_static_branch(struct static_key *key, + bool branch) +{ + asm_volatile_goto( + "1: nop32 \n" + " .pushsection __jump_table, \"aw\" \n" + " .align 2 \n" + " .long 1b - ., %l[label] - . \n" + " .long %0 - . \n" + " .popsection \n" + : : "i"(&((char *)key)[branch]) : : label); + + return false; +label: + return true; +} + +static __always_inline bool arch_static_branch_jump(struct static_key *key, + bool branch) +{ + asm_volatile_goto( + "1: bsr32 %l[label] \n" + " .pushsection __jump_table, \"aw\" \n" + " .align 2 \n" + " .long 1b - ., %l[label] - . \n" + " .long %0 - . \n" + " .popsection \n" + : : "i"(&((char *)key)[branch]) : : label); + + return false; +label: + return true; +} + +#endif /* __ASSEMBLY__ */ +#endif /* __ASM_CSKY_JUMP_LABEL_H */ diff --git a/arch/csky/kernel/Makefile b/arch/csky/kernel/Makefile index 4eb41421ca5b..6f14c924b20d 100644 --- a/arch/csky/kernel/Makefile +++ b/arch/csky/kernel/Makefile @@ -13,6 +13,7 @@ obj-$(CONFIG_STACKTRACE) += stacktrace.o obj-$(CONFIG_CSKY_PMU_V1) += perf_event.o obj-$(CONFIG_PERF_EVENTS) += perf_callchain.o obj-$(CONFIG_HAVE_PERF_REGS) += perf_regs.o +obj-$(CONFIG_JUMP_LABEL) += jump_label.o ifdef CONFIG_FUNCTION_TRACER CFLAGS_REMOVE_ftrace.o = $(CC_FLAGS_FTRACE) diff --git a/arch/csky/kernel/jump_label.c b/arch/csky/kernel/jump_label.c new file mode 100644 index 000000000000..d0e8b21447e1 --- /dev/null +++ b/arch/csky/kernel/jump_label.c @@ -0,0 +1,54 @@ +// SPDX-License-Identifier: GPL-2.0-only + +#include <linux/jump_label.h> +#include <linux/kernel.h> +#include <linux/memory.h> +#include <linux/mutex.h> +#include <linux/uaccess.h> +#include <asm/cacheflush.h> + +#define NOP32_HI 0xc400 +#define NOP32_LO 0x4820 +#define BSR_LINK 0xe000 + +void arch_jump_label_transform(struct jump_entry *entry, + enum jump_label_type type) +{ + unsigned long addr = jump_entry_code(entry); + u16 insn[2]; + int ret = 0; + + if (type == JUMP_LABEL_JMP) { + long offset = jump_entry_target(entry) - jump_entry_code(entry); + + if (WARN_ON(offset & 1 || offset < -67108864 || offset >= 67108864)) + return; + + offset = offset >> 1; + + insn[0] = BSR_LINK | + ((uint16_t)((unsigned long) offset >> 16) & 0x3ff); + insn[1] = (uint16_t)((unsigned long) offset & 0xffff); + } else { + insn[0] = NOP32_HI; + insn[1] = NOP32_LO; + } + + ret = copy_to_kernel_nofault((void *)addr, insn, 4); + WARN_ON(ret); + + flush_icache_range(addr, addr + 4); +} + +void arch_jump_label_transform_static(struct jump_entry *entry, + enum jump_label_type type) +{ + /* + * We use the same instructions in the arch_static_branch and + * arch_static_branch_jump inline functions, so there's no + * need to patch them up here. + * The core will call arch_jump_label_transform when those + * instructions need to be replaced. + */ + arch_jump_label_transform(entry, type); +} |