diff options
Diffstat (limited to 'arch/mips/kernel/jump_label.c')
| -rw-r--r-- | arch/mips/kernel/jump_label.c | 54 |
1 files changed, 54 insertions, 0 deletions
diff --git a/arch/mips/kernel/jump_label.c b/arch/mips/kernel/jump_label.c new file mode 100644 index 000000000000..6001610cfe55 --- /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 */ |