linux-stable/arch/parisc/include/asm/alternative.h
Helge Deller 33f806da2d parisc: Mark altinstructions read-only and 32-bit aligned
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org   # v6.0+
2023-11-25 09:43:17 +01:00

66 lines
2 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __ASM_PARISC_ALTERNATIVE_H
#define __ASM_PARISC_ALTERNATIVE_H
#define ALT_COND_ALWAYS 0x80 /* always replace instruction */
#define ALT_COND_NO_SMP 0x01 /* when running UP instead of SMP */
#define ALT_COND_NO_DCACHE 0x02 /* if system has no d-cache */
#define ALT_COND_NO_ICACHE 0x04 /* if system has no i-cache */
#define ALT_COND_NO_SPLIT_TLB 0x08 /* if split_tlb == 0 */
#define ALT_COND_NO_IOC_FDC 0x10 /* if I/O cache does not need flushes */
#define ALT_COND_RUN_ON_QEMU 0x20 /* if running on QEMU */
#define INSN_PxTLB 0x02 /* modify pdtlb, pitlb */
#define INSN_NOP 0x08000240 /* nop */
#ifndef __ASSEMBLY__
#include <linux/init.h>
#include <linux/types.h>
#include <linux/stddef.h>
#include <linux/stringify.h>
struct alt_instr {
s32 orig_offset; /* offset to original instructions */
s16 len; /* end of original instructions */
u16 cond; /* see ALT_COND_XXX */
u32 replacement; /* replacement instruction or code */
} __packed;
void set_kernel_text_rw(int enable_read_write);
void apply_alternatives_all(void);
void apply_alternatives(struct alt_instr *start, struct alt_instr *end,
const char *module_name);
/* Alternative SMP implementation. */
#define ALTERNATIVE(cond, replacement) "!0:" \
".section .altinstructions, \"a\" !" \
".align 4 !" \
".word (0b-4-.) !" \
".hword 1, " __stringify(cond) " !" \
".word " __stringify(replacement) " !" \
".previous"
#else
/* to replace one single instructions by a new instruction */
#define ALTERNATIVE(from, to, cond, replacement)\
.section .altinstructions, "a" ! \
.align 4 ! \
.word (from - .) ! \
.hword (to - from)/4, cond ! \
.word replacement ! \
.previous
/* to replace multiple instructions by new code */
#define ALTERNATIVE_CODE(from, num_instructions, cond, new_instr_ptr)\
.section .altinstructions, "a" ! \
.align 4 ! \
.word (from - .) ! \
.hword -num_instructions, cond ! \
.word (new_instr_ptr - .) ! \
.previous
#endif /* __ASSEMBLY__ */
#endif /* __ASM_PARISC_ALTERNATIVE_H */