diff options
Diffstat (limited to 'arch/mips')
| -rw-r--r-- | arch/mips/Kconfig | 1 | ||||
| -rw-r--r-- | arch/mips/include/asm/jump_label.h | 48 | ||||
| -rw-r--r-- | arch/mips/kernel/Makefile | 2 | ||||
| -rw-r--r-- | arch/mips/kernel/jump_label.c | 54 | ||||
| -rw-r--r-- | arch/mips/kernel/module.c | 5 |
5 files changed, 110 insertions, 0 deletions
diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig index 2106781d747..95430406822 100644 --- a/arch/mips/Kconfig +++ b/arch/mips/Kconfig @@ -21,6 +21,7 @@ config MIPS select HAVE_DMA_API_DEBUG select HAVE_GENERIC_HARDIRQS select GENERIC_IRQ_PROBE + select HAVE_ARCH_JUMP_LABEL menu "Machine selection" diff --git a/arch/mips/include/asm/jump_label.h b/arch/mips/include/asm/jump_label.h new file mode 100644 index 00000000000..7622ccf7507 --- /dev/null +++ b/arch/mips/include/asm/jump_label.h @@ -0,0 +1,48 @@ +/* + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + * + * Copyright (c) 2010 Cavium Networks, Inc. + */ +#ifndef _ASM_MIPS_JUMP_LABEL_H +#define _ASM_MIPS_JUMP_LABEL_H + +#include <linux/types.h> + +#ifdef __KERNEL__ + +#define JUMP_LABEL_NOP_SIZE 4 + +#ifdef CONFIG_64BIT +#define WORD_INSN ".dword" +#else +#define WORD_INSN ".word" +#endif + +#define JUMP_LABEL(key, label) \ + do { \ + asm goto("1:\tnop\n\t" \ + "nop\n\t" \ + ".pushsection __jump_table, \"a\"\n\t" \ + WORD_INSN " 1b, %l[" #label "], %0\n\t" \ + ".popsection\n\t" \ + : : "i" (key) : : label); \ + } while (0) + + +#endif /* __KERNEL__ */ + +#ifdef CONFIG_64BIT +typedef u64 jump_label_t; +#else +typedef u32 jump_label_t; +#endif + +struct jump_entry { + jump_label_t code; + jump_label_t target; + jump_label_t key; +}; + +#endif /* _ASM_MIPS_JUMP_LABEL_H */ diff --git a/arch/mips/kernel/Makefile b/arch/mips/kernel/Makefile index 39773979ca6..cedee2bcbd1 100644 --- a/arch/mips/kernel/Makefile +++ b/arch/mips/kernel/Makefile @@ -107,4 +107,6 @@ obj-$(CONFIG_MIPS_CPUFREQ) += cpufreq/ obj-$(CONFIG_HW_PERF_EVENTS) += perf_event.o +obj-$(CONFIG_JUMP_LABEL) += jump_label.o + CPPFLAGS_vmlinux.lds := $(KBUILD_CFLAGS) diff --git a/arch/mips/kernel/jump_label.c b/arch/mips/kernel/jump_label.c new file mode 100644 index 00000000000..6001610cfe5 --- /dev/null +++ b/arch/mips/kernel/jump_label.c @@ -0,0 +1,54 @@ +/* + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + * + * Copyright (c) 2010 Cavium Networks, Inc. + */ + +#include <linux/jump_label.h> +#include <linux/kernel.h> +#include <linux/memory.h> +#include <linux/mutex.h> +#include <linux/types.h> +#include <linux/cpu.h> + +#include <asm/cacheflush.h> +#include <asm/inst.h> + +#ifdef HAVE_JUMP_LABEL + +#define J_RANGE_MASK ((1ul << 28) - 1) + +void arch_jump_label_transform(struct jump_entry *e, + enum jump_label_type type) +{ + union mips_instruction insn; + union mips_instruction *insn_p = + (union mips_instruction *)(unsigned long)e->code; + + /* Jump only works within a 256MB aligned region. */ + BUG_ON((e->target & ~J_RANGE_MASK) != (e->code & ~J_RANGE_MASK)); + + /* Target must have 4 byte alignment. */ + BUG_ON((e->target & 3) != 0); + + if (type == JUMP_LABEL_ENABLE) { + insn.j_format.opcode = j_op; + insn.j_format.target = (e->target & J_RANGE_MASK) >> 2; + } else { + insn.word = 0; /* nop */ + } + + get_online_cpus(); + mutex_lock(&text_mutex); + *insn_p = insn; + + flush_icache_range((unsigned long)insn_p, + (unsigned long)insn_p + sizeof(*insn_p)); + + mutex_unlock(&text_mutex); + put_online_cpus(); +} + +#endif /* HAVE_JUMP_LABEL */ diff --git a/arch/mips/kernel/module.c b/arch/mips/kernel/module.c index d87a72e9fac..dd940b70196 100644 --- a/arch/mips/kernel/module.c +++ b/arch/mips/kernel/module.c @@ -30,6 +30,8 @@ #include <linux/kernel.h> #include <linux/module.h> #include <linux/spinlock.h> +#include <linux/jump_label.h> + #include <asm/pgtable.h> /* MODULE_START */ struct mips_hi16 { @@ -382,6 +384,9 @@ int module_finalize(const Elf_Ehdr *hdr, const Elf_Shdr *s; char *secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset; + /* Make jump label nops. */ + jump_label_apply_nops(me); + INIT_LIST_HEAD(&me->arch.dbe_list); for (s = sechdrs; s < sechdrs + hdr->e_shnum; s++) { if (strcmp("__dbe_table", secstrings + s->sh_name) != 0) |