mirror of https://gitee.com/openkylin/linux.git
151 lines
5.0 KiB
C
151 lines
5.0 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
|
|
#ifndef _ASM_S390_ALTERNATIVE_H
|
|
#define _ASM_S390_ALTERNATIVE_H
|
|
|
|
#ifndef __ASSEMBLY__
|
|
|
|
#include <linux/types.h>
|
|
#include <linux/stddef.h>
|
|
#include <linux/stringify.h>
|
|
|
|
struct alt_instr {
|
|
s32 instr_offset; /* original instruction */
|
|
s32 repl_offset; /* offset to replacement instruction */
|
|
u16 facility; /* facility bit set for replacement */
|
|
u8 instrlen; /* length of original instruction */
|
|
u8 replacementlen; /* length of new instruction */
|
|
} __packed;
|
|
|
|
void apply_alternative_instructions(void);
|
|
void apply_alternatives(struct alt_instr *start, struct alt_instr *end);
|
|
|
|
/*
|
|
* |661: |662: |6620 |663:
|
|
* +-----------+---------------------+
|
|
* | oldinstr | oldinstr_padding |
|
|
* | +----------+----------+
|
|
* | | | |
|
|
* | | >6 bytes |6/4/2 nops|
|
|
* | |6 bytes jg----------->
|
|
* +-----------+---------------------+
|
|
* ^^ static padding ^^
|
|
*
|
|
* .altinstr_replacement section
|
|
* +---------------------+-----------+
|
|
* |6641: |6651:
|
|
* | alternative instr 1 |
|
|
* +-----------+---------+- - - - - -+
|
|
* |6642: |6652: |
|
|
* | alternative instr 2 | padding
|
|
* +---------------------+- - - - - -+
|
|
* ^ runtime ^
|
|
*
|
|
* .altinstructions section
|
|
* +---------------------------------+
|
|
* | alt_instr entries for each |
|
|
* | alternative instr |
|
|
* +---------------------------------+
|
|
*/
|
|
|
|
#define b_altinstr(num) "664"#num
|
|
#define e_altinstr(num) "665"#num
|
|
|
|
#define e_oldinstr_pad_end "663"
|
|
#define oldinstr_len "662b-661b"
|
|
#define oldinstr_total_len e_oldinstr_pad_end"b-661b"
|
|
#define altinstr_len(num) e_altinstr(num)"b-"b_altinstr(num)"b"
|
|
#define oldinstr_pad_len(num) \
|
|
"-(((" altinstr_len(num) ")-(" oldinstr_len ")) > 0) * " \
|
|
"((" altinstr_len(num) ")-(" oldinstr_len "))"
|
|
|
|
#define INSTR_LEN_SANITY_CHECK(len) \
|
|
".if " len " > 254\n" \
|
|
"\t.error \"cpu alternatives does not support instructions " \
|
|
"blocks > 254 bytes\"\n" \
|
|
".endif\n" \
|
|
".if (" len ") %% 2\n" \
|
|
"\t.error \"cpu alternatives instructions length is odd\"\n" \
|
|
".endif\n"
|
|
|
|
#define OLDINSTR_PADDING(oldinstr, num) \
|
|
".if " oldinstr_pad_len(num) " > 6\n" \
|
|
"\tjg " e_oldinstr_pad_end "f\n" \
|
|
"6620:\n" \
|
|
"\t.fill (" oldinstr_pad_len(num) " - (6620b-662b)) / 2, 2, 0x0700\n" \
|
|
".else\n" \
|
|
"\t.fill " oldinstr_pad_len(num) " / 6, 6, 0xc0040000\n" \
|
|
"\t.fill " oldinstr_pad_len(num) " %% 6 / 4, 4, 0x47000000\n" \
|
|
"\t.fill " oldinstr_pad_len(num) " %% 6 %% 4 / 2, 2, 0x0700\n" \
|
|
".endif\n"
|
|
|
|
#define OLDINSTR(oldinstr, num) \
|
|
"661:\n\t" oldinstr "\n662:\n" \
|
|
OLDINSTR_PADDING(oldinstr, num) \
|
|
e_oldinstr_pad_end ":\n" \
|
|
INSTR_LEN_SANITY_CHECK(oldinstr_len)
|
|
|
|
#define OLDINSTR_2(oldinstr, num1, num2) \
|
|
"661:\n\t" oldinstr "\n662:\n" \
|
|
".if " altinstr_len(num1) " < " altinstr_len(num2) "\n" \
|
|
OLDINSTR_PADDING(oldinstr, num2) \
|
|
".else\n" \
|
|
OLDINSTR_PADDING(oldinstr, num1) \
|
|
".endif\n" \
|
|
e_oldinstr_pad_end ":\n" \
|
|
INSTR_LEN_SANITY_CHECK(oldinstr_len)
|
|
|
|
#define ALTINSTR_ENTRY(facility, num) \
|
|
"\t.long 661b - .\n" /* old instruction */ \
|
|
"\t.long " b_altinstr(num)"b - .\n" /* alt instruction */ \
|
|
"\t.word " __stringify(facility) "\n" /* facility bit */ \
|
|
"\t.byte " oldinstr_total_len "\n" /* source len */ \
|
|
"\t.byte " altinstr_len(num) "\n" /* alt instruction len */
|
|
|
|
#define ALTINSTR_REPLACEMENT(altinstr, num) /* replacement */ \
|
|
b_altinstr(num)":\n\t" altinstr "\n" e_altinstr(num) ":\n" \
|
|
INSTR_LEN_SANITY_CHECK(altinstr_len(num))
|
|
|
|
/* alternative assembly primitive: */
|
|
#define ALTERNATIVE(oldinstr, altinstr, facility) \
|
|
".pushsection .altinstr_replacement, \"ax\"\n" \
|
|
ALTINSTR_REPLACEMENT(altinstr, 1) \
|
|
".popsection\n" \
|
|
OLDINSTR(oldinstr, 1) \
|
|
".pushsection .altinstructions,\"a\"\n" \
|
|
ALTINSTR_ENTRY(facility, 1) \
|
|
".popsection\n"
|
|
|
|
#define ALTERNATIVE_2(oldinstr, altinstr1, facility1, altinstr2, facility2)\
|
|
".pushsection .altinstr_replacement, \"ax\"\n" \
|
|
ALTINSTR_REPLACEMENT(altinstr1, 1) \
|
|
ALTINSTR_REPLACEMENT(altinstr2, 2) \
|
|
".popsection\n" \
|
|
OLDINSTR_2(oldinstr, 1, 2) \
|
|
".pushsection .altinstructions,\"a\"\n" \
|
|
ALTINSTR_ENTRY(facility1, 1) \
|
|
ALTINSTR_ENTRY(facility2, 2) \
|
|
".popsection\n"
|
|
|
|
/*
|
|
* Alternative instructions for different CPU types or capabilities.
|
|
*
|
|
* This allows to use optimized instructions even on generic binary
|
|
* kernels.
|
|
*
|
|
* oldinstr is padded with jump and nops at compile time if altinstr is
|
|
* longer. altinstr is padded with jump and nops at run-time during patching.
|
|
*
|
|
* For non barrier like inlines please define new variants
|
|
* without volatile and memory clobber.
|
|
*/
|
|
#define alternative(oldinstr, altinstr, facility) \
|
|
asm volatile(ALTERNATIVE(oldinstr, altinstr, facility) : : : "memory")
|
|
|
|
#define alternative_2(oldinstr, altinstr1, facility1, altinstr2, facility2) \
|
|
asm volatile(ALTERNATIVE_2(oldinstr, altinstr1, facility1, \
|
|
altinstr2, facility2) ::: "memory")
|
|
|
|
#endif /* __ASSEMBLY__ */
|
|
|
|
#endif /* _ASM_S390_ALTERNATIVE_H */
|