| 5,6 → 5,7 |
|---|
| #include <linux/stddef.h> |
| #include <linux/stringify.h> |
| #include <asm/asm.h> |
| #include <asm/ptrace.h> |
| |
| /* |
| * Alternative inline assembly for SMP. |
| 47,9 → 48,16 |
|---|
| s32 repl_offset; /* offset to replacement instruction */ |
| u16 cpuid; /* cpuid bit set for replacement */ |
| u8 instrlen; /* length of original instruction */ |
| u8 replacementlen; /* length of new instruction, <= instrlen */ |
| }; |
| u8 replacementlen; /* length of new instruction */ |
| u8 padlen; /* length of build-time padding */ |
| } __packed; |
| |
| /* |
| * Debug flag that can be tested to see whether alternative |
| * instructions were patched in already: |
| */ |
| extern int alternatives_patched; |
| |
| extern void alternative_instructions(void); |
| extern void apply_alternatives(struct alt_instr *start, struct alt_instr *end); |
| |
| 75,50 → 83,69 |
|---|
| } |
| #endif /* CONFIG_SMP */ |
| |
| #define OLDINSTR(oldinstr) "661:\n\t" oldinstr "\n662:\n" |
| #define b_replacement(num) "664"#num |
| #define e_replacement(num) "665"#num |
| |
| #define b_replacement(number) "663"#number |
| #define e_replacement(number) "664"#number |
| |
| #define alt_end_marker "663" |
| #define alt_slen "662b-661b" |
| #define alt_rlen(number) e_replacement(number)"f-"b_replacement(number)"f" |
| #define alt_pad_len alt_end_marker"b-662b" |
| #define alt_total_slen alt_end_marker"b-661b" |
| #define alt_rlen(num) e_replacement(num)"f-"b_replacement(num)"f" |
| |
| #define ALTINSTR_ENTRY(feature, number) \ |
| #define __OLDINSTR(oldinstr, num) \ |
| "661:\n\t" oldinstr "\n662:\n" \ |
| ".skip -(((" alt_rlen(num) ")-(" alt_slen ")) > 0) * " \ |
| "((" alt_rlen(num) ")-(" alt_slen ")),0x90\n" |
| |
| #define OLDINSTR(oldinstr, num) \ |
| __OLDINSTR(oldinstr, num) \ |
| alt_end_marker ":\n" |
| |
| /* |
| * max without conditionals. Idea adapted from: |
| * http://graphics.stanford.edu/~seander/bithacks.html#IntegerMinOrMax |
| * |
| * The additional "-" is needed because gas works with s32s. |
| */ |
| #define alt_max_short(a, b) "((" a ") ^ (((" a ") ^ (" b ")) & -(-((" a ") - (" b ")))))" |
| |
| /* |
| * Pad the second replacement alternative with additional NOPs if it is |
| * additionally longer than the first replacement alternative. |
| */ |
| #define OLDINSTR_2(oldinstr, num1, num2) \ |
| "661:\n\t" oldinstr "\n662:\n" \ |
| ".skip -((" alt_max_short(alt_rlen(num1), alt_rlen(num2)) " - (" alt_slen ")) > 0) * " \ |
| "(" alt_max_short(alt_rlen(num1), alt_rlen(num2)) " - (" alt_slen ")), 0x90\n" \ |
| alt_end_marker ":\n" |
| |
| #define ALTINSTR_ENTRY(feature, num) \ |
| " .long 661b - .\n" /* label */ \ |
| " .long " b_replacement(number)"f - .\n" /* new instruction */ \ |
| " .long " b_replacement(num)"f - .\n" /* new instruction */ \ |
| " .word " __stringify(feature) "\n" /* feature bit */ \ |
| " .byte " alt_slen "\n" /* source len */ \ |
| " .byte " alt_rlen(number) "\n" /* replacement len */ |
| " .byte " alt_total_slen "\n" /* source len */ \ |
| " .byte " alt_rlen(num) "\n" /* replacement len */ \ |
| " .byte " alt_pad_len "\n" /* pad len */ |
| |
| #define DISCARD_ENTRY(number) /* rlen <= slen */ \ |
| " .byte 0xff + (" alt_rlen(number) ") - (" alt_slen ")\n" |
| #define ALTINSTR_REPLACEMENT(newinstr, feature, num) /* replacement */ \ |
| b_replacement(num)":\n\t" newinstr "\n" e_replacement(num) ":\n\t" |
| |
| #define ALTINSTR_REPLACEMENT(newinstr, feature, number) /* replacement */ \ |
| b_replacement(number)":\n\t" newinstr "\n" e_replacement(number) ":\n\t" |
| |
| /* alternative assembly primitive: */ |
| #define ALTERNATIVE(oldinstr, newinstr, feature) \ |
| OLDINSTR(oldinstr) \ |
| OLDINSTR(oldinstr, 1) \ |
| ".pushsection .altinstructions,\"a\"\n" \ |
| ALTINSTR_ENTRY(feature, 1) \ |
| ".popsection\n" \ |
| ".pushsection .discard,\"aw\",@progbits\n" \ |
| DISCARD_ENTRY(1) \ |
| ".popsection\n" \ |
| ".pushsection .altinstr_replacement, \"ax\"\n" \ |
| ALTINSTR_REPLACEMENT(newinstr, feature, 1) \ |
| ".popsection" |
| |
| #define ALTERNATIVE_2(oldinstr, newinstr1, feature1, newinstr2, feature2)\ |
| OLDINSTR(oldinstr) \ |
| OLDINSTR_2(oldinstr, 1, 2) \ |
| ".pushsection .altinstructions,\"a\"\n" \ |
| ALTINSTR_ENTRY(feature1, 1) \ |
| ALTINSTR_ENTRY(feature2, 2) \ |
| ".popsection\n" \ |
| ".pushsection .discard,\"aw\",@progbits\n" \ |
| DISCARD_ENTRY(1) \ |
| DISCARD_ENTRY(2) \ |
| ".popsection\n" \ |
| ".pushsection .altinstr_replacement, \"ax\"\n" \ |
| ALTINSTR_REPLACEMENT(newinstr1, feature1, 1) \ |
| ALTINSTR_REPLACEMENT(newinstr2, feature2, 2) \ |
| 145,6 → 172,9 |
|---|
| #define alternative(oldinstr, newinstr, feature) \ |
| asm volatile (ALTERNATIVE(oldinstr, newinstr, feature) : : : "memory") |
| |
| #define alternative_2(oldinstr, newinstr1, feature1, newinstr2, feature2) \ |
| asm volatile(ALTERNATIVE_2(oldinstr, newinstr1, feature1, newinstr2, feature2) ::: "memory") |
| |
| /* |
| * Alternative inline assembly with input. |
| * |