diff options
author | Al Viro <viro@zeniv.linux.org.uk> | 2020-07-16 17:19:37 +0300 |
---|---|---|
committer | Al Viro <viro@zeniv.linux.org.uk> | 2021-01-04 04:05:17 +0300 |
commit | c4da8e0dc6f7cec80f32af080cadf47c1753a2ab (patch) | |
tree | 3bf7e849fce58917c8fbd2b8e24351adb1fd9b69 /arch/sparc | |
parent | cfd5fa7021a54b8ed9bad16246b6b34851fd48d1 (diff) | |
download | linux-c4da8e0dc6f7cec80f32af080cadf47c1753a2ab.tar.xz |
sparc32: switch copy_user.S away from range exception table entries
Those were the last range exception table entries, which will allow
to get rid of a lot of weirdness. Emits the same code into .text.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Diffstat (limited to 'arch/sparc')
-rw-r--r-- | arch/sparc/lib/copy_user.S | 315 |
1 files changed, 112 insertions, 203 deletions
diff --git a/arch/sparc/lib/copy_user.S b/arch/sparc/lib/copy_user.S index dc72f2b970b7..954572c78539 100644 --- a/arch/sparc/lib/copy_user.S +++ b/arch/sparc/lib/copy_user.S @@ -21,98 +21,134 @@ /* Work around cpp -rob */ #define ALLOC #alloc #define EXECINSTR #execinstr + +#define EX_ENTRY(l1, l2) \ + .section __ex_table,ALLOC; \ + .align 4; \ + .word l1, l2; \ + .text; + #define EX(x,y,a,b) \ 98: x,y; \ .section .fixup,ALLOC,EXECINSTR; \ .align 4; \ -99: ba fixupretl; \ - a, b, %g3; \ - .section __ex_table,ALLOC; \ - .align 4; \ - .word 98b, 99b; \ - .text; \ - .align 4 +99: retl; \ + a, b, %o0; \ + EX_ENTRY(98b, 99b) #define EX2(x,y,c,d,e,a,b) \ 98: x,y; \ .section .fixup,ALLOC,EXECINSTR; \ .align 4; \ 99: c, d, e; \ - ba fixupretl; \ - a, b, %g3; \ - .section __ex_table,ALLOC; \ - .align 4; \ - .word 98b, 99b; \ - .text; \ - .align 4 + retl; \ + a, b, %o0; \ + EX_ENTRY(98b, 99b) #define EXO2(x,y) \ 98: x, y; \ - .section __ex_table,ALLOC; \ - .align 4; \ - .word 98b, 97f; \ - .text; \ - .align 4 + EX_ENTRY(98b, 97f) -#define EXT(start,end,handler) \ - .section __ex_table,ALLOC; \ - .align 4; \ - .word start, 0, end, handler; \ - .text; \ - .align 4 +#define LD(insn, src, offset, reg, label) \ +98: insn [%src + (offset)], %reg; \ + .section .fixup,ALLOC,EXECINSTR; \ +99: ba label; \ + mov offset, %g5; \ + EX_ENTRY(98b, 99b) -/* Please do not change following macros unless you change logic used - * in .fixup at the end of this file as well - */ +#define ST(insn, dst, offset, reg, label) \ +98: insn %reg, [%dst + (offset)]; \ + .section .fixup,ALLOC,EXECINSTR; \ +99: ba label; \ + mov offset, %g5; \ + EX_ENTRY(98b, 99b) /* Both these macros have to start with exactly the same insn */ +/* left: g7 + (g1 % 128) - offset */ #define MOVE_BIGCHUNK(src, dst, offset, t0, t1, t2, t3, t4, t5, t6, t7) \ - ldd [%src + (offset) + 0x00], %t0; \ - ldd [%src + (offset) + 0x08], %t2; \ - ldd [%src + (offset) + 0x10], %t4; \ - ldd [%src + (offset) + 0x18], %t6; \ - st %t0, [%dst + (offset) + 0x00]; \ - st %t1, [%dst + (offset) + 0x04]; \ - st %t2, [%dst + (offset) + 0x08]; \ - st %t3, [%dst + (offset) + 0x0c]; \ - st %t4, [%dst + (offset) + 0x10]; \ - st %t5, [%dst + (offset) + 0x14]; \ - st %t6, [%dst + (offset) + 0x18]; \ - st %t7, [%dst + (offset) + 0x1c]; - + LD(ldd, src, offset + 0x00, t0, bigchunk_fault) \ + LD(ldd, src, offset + 0x08, t2, bigchunk_fault) \ + LD(ldd, src, offset + 0x10, t4, bigchunk_fault) \ + LD(ldd, src, offset + 0x18, t6, bigchunk_fault) \ + ST(st, dst, offset + 0x00, t0, bigchunk_fault) \ + ST(st, dst, offset + 0x04, t1, bigchunk_fault) \ + ST(st, dst, offset + 0x08, t2, bigchunk_fault) \ + ST(st, dst, offset + 0x0c, t3, bigchunk_fault) \ + ST(st, dst, offset + 0x10, t4, bigchunk_fault) \ + ST(st, dst, offset + 0x14, t5, bigchunk_fault) \ + ST(st, dst, offset + 0x18, t6, bigchunk_fault) \ + ST(st, dst, offset + 0x1c, t7, bigchunk_fault) + +/* left: g7 + (g1 % 128) - offset */ #define MOVE_BIGALIGNCHUNK(src, dst, offset, t0, t1, t2, t3, t4, t5, t6, t7) \ - ldd [%src + (offset) + 0x00], %t0; \ - ldd [%src + (offset) + 0x08], %t2; \ - ldd [%src + (offset) + 0x10], %t4; \ - ldd [%src + (offset) + 0x18], %t6; \ - std %t0, [%dst + (offset) + 0x00]; \ - std %t2, [%dst + (offset) + 0x08]; \ - std %t4, [%dst + (offset) + 0x10]; \ - std %t6, [%dst + (offset) + 0x18]; + LD(ldd, src, offset + 0x00, t0, bigchunk_fault) \ + LD(ldd, src, offset + 0x08, t2, bigchunk_fault) \ + LD(ldd, src, offset + 0x10, t4, bigchunk_fault) \ + LD(ldd, src, offset + 0x18, t6, bigchunk_fault) \ + ST(std, dst, offset + 0x00, t0, bigchunk_fault) \ + ST(std, dst, offset + 0x08, t2, bigchunk_fault) \ + ST(std, dst, offset + 0x10, t4, bigchunk_fault) \ + ST(std, dst, offset + 0x18, t6, bigchunk_fault) + .section .fixup,#alloc,#execinstr +bigchunk_fault: + sub %g7, %g5, %o0 + and %g1, 127, %g1 + retl + add %o0, %g1, %o0 + +/* left: offset + 16 + (g1 % 16) */ #define MOVE_LASTCHUNK(src, dst, offset, t0, t1, t2, t3) \ - ldd [%src - (offset) - 0x10], %t0; \ - ldd [%src - (offset) - 0x08], %t2; \ - st %t0, [%dst - (offset) - 0x10]; \ - st %t1, [%dst - (offset) - 0x0c]; \ - st %t2, [%dst - (offset) - 0x08]; \ - st %t3, [%dst - (offset) - 0x04]; + LD(ldd, src, -(offset + 0x10), t0, lastchunk_fault) \ + LD(ldd, src, -(offset + 0x08), t2, lastchunk_fault) \ + ST(st, dst, -(offset + 0x10), t0, lastchunk_fault) \ + ST(st, dst, -(offset + 0x0c), t1, lastchunk_fault) \ + ST(st, dst, -(offset + 0x08), t2, lastchunk_fault) \ + ST(st, dst, -(offset + 0x04), t3, lastchunk_fault) -#define MOVE_HALFCHUNK(src, dst, offset, t0, t1, t2, t3) \ - lduh [%src + (offset) + 0x00], %t0; \ - lduh [%src + (offset) + 0x02], %t1; \ - lduh [%src + (offset) + 0x04], %t2; \ - lduh [%src + (offset) + 0x06], %t3; \ - sth %t0, [%dst + (offset) + 0x00]; \ - sth %t1, [%dst + (offset) + 0x02]; \ - sth %t2, [%dst + (offset) + 0x04]; \ - sth %t3, [%dst + (offset) + 0x06]; + .section .fixup,#alloc,#execinstr +lastchunk_fault: + and %g1, 15, %g1 + retl + sub %g1, %g5, %o0 +/* left: o3 + (o2 % 16) - offset */ +#define MOVE_HALFCHUNK(src, dst, offset, t0, t1, t2, t3) \ + LD(lduh, src, offset + 0x00, t0, halfchunk_fault) \ + LD(lduh, src, offset + 0x02, t1, halfchunk_fault) \ + LD(lduh, src, offset + 0x04, t2, halfchunk_fault) \ + LD(lduh, src, offset + 0x06, t3, halfchunk_fault) \ + ST(sth, dst, offset + 0x00, t0, halfchunk_fault) \ + ST(sth, dst, offset + 0x02, t1, halfchunk_fault) \ + ST(sth, dst, offset + 0x04, t2, halfchunk_fault) \ + ST(sth, dst, offset + 0x06, t3, halfchunk_fault) + +/* left: o3 + (o2 % 16) + offset + 2 */ #define MOVE_SHORTCHUNK(src, dst, offset, t0, t1) \ - ldub [%src - (offset) - 0x02], %t0; \ - ldub [%src - (offset) - 0x01], %t1; \ - stb %t0, [%dst - (offset) - 0x02]; \ - stb %t1, [%dst - (offset) - 0x01]; + LD(ldub, src, -(offset + 0x02), t0, halfchunk_fault) \ + LD(ldub, src, -(offset + 0x01), t1, halfchunk_fault) \ + ST(stb, dst, -(offset + 0x02), t0, halfchunk_fault) \ + ST(stb, dst, -(offset + 0x01), t1, halfchunk_fault) + + .section .fixup,#alloc,#execinstr +halfchunk_fault: + and %o2, 15, %o2 + sub %o3, %g5, %o3 + retl + add %o2, %o3, %o0 + +/* left: offset + 2 + (o2 % 2) */ +#define MOVE_LAST_SHORTCHUNK(src, dst, offset, t0, t1) \ + LD(ldub, src, -(offset + 0x02), t0, last_shortchunk_fault) \ + LD(ldub, src, -(offset + 0x01), t1, last_shortchunk_fault) \ + ST(stb, dst, -(offset + 0x02), t0, last_shortchunk_fault) \ + ST(stb, dst, -(offset + 0x01), t1, last_shortchunk_fault) + + .section .fixup,#alloc,#execinstr +last_shortchunk_fault: + and %o2, 1, %o2 + retl + sub %o2, %g5, %o0 .text .align 4 @@ -182,8 +218,6 @@ __copy_user: /* %o0=dst %o1=src %o2=len */ MOVE_BIGCHUNK(o1, o0, 0x20, o2, o3, o4, o5, g2, g3, g4, g5) MOVE_BIGCHUNK(o1, o0, 0x40, o2, o3, o4, o5, g2, g3, g4, g5) MOVE_BIGCHUNK(o1, o0, 0x60, o2, o3, o4, o5, g2, g3, g4, g5) -80: - EXT(5b, 80b, 50f) subcc %g7, 128, %g7 add %o1, 128, %o1 bne 5b @@ -201,7 +235,6 @@ __copy_user: /* %o0=dst %o1=src %o2=len */ jmpl %o5 + %lo(copy_user_table_end), %g0 add %o0, %g7, %o0 -copy_user_table: MOVE_LASTCHUNK(o1, o0, 0x60, g2, g3, g4, g5) MOVE_LASTCHUNK(o1, o0, 0x50, g2, g3, g4, g5) MOVE_LASTCHUNK(o1, o0, 0x40, g2, g3, g4, g5) @@ -210,7 +243,6 @@ copy_user_table: MOVE_LASTCHUNK(o1, o0, 0x10, g2, g3, g4, g5) MOVE_LASTCHUNK(o1, o0, 0x00, g2, g3, g4, g5) copy_user_table_end: - EXT(copy_user_table, copy_user_table_end, 51f) be copy_user_last7 andcc %g1, 4, %g0 @@ -250,8 +282,6 @@ ldd_std: MOVE_BIGALIGNCHUNK(o1, o0, 0x20, o2, o3, o4, o5, g2, g3, g4, g5) MOVE_BIGALIGNCHUNK(o1, o0, 0x40, o2, o3, o4, o5, g2, g3, g4, g5) MOVE_BIGALIGNCHUNK(o1, o0, 0x60, o2, o3, o4, o5, g2, g3, g4, g5) -81: - EXT(ldd_std, 81b, 52f) subcc %g7, 128, %g7 add %o1, 128, %o1 bne ldd_std @@ -290,8 +320,6 @@ cannot_optimize: 10: MOVE_HALFCHUNK(o1, o0, 0x00, g2, g3, g4, g5) MOVE_HALFCHUNK(o1, o0, 0x08, g2, g3, g4, g5) -82: - EXT(10b, 82b, 53f) subcc %o3, 0x10, %o3 add %o1, 0x10, %o1 bne 10b @@ -308,8 +336,6 @@ byte_chunk: MOVE_SHORTCHUNK(o1, o0, -0x0c, g2, g3) MOVE_SHORTCHUNK(o1, o0, -0x0e, g2, g3) MOVE_SHORTCHUNK(o1, o0, -0x10, g2, g3) -83: - EXT(byte_chunk, 83b, 54f) subcc %o3, 0x10, %o3 add %o1, 0x10, %o1 bne byte_chunk @@ -325,16 +351,14 @@ short_end: add %o1, %o3, %o1 jmpl %o5 + %lo(short_table_end), %g0 andcc %o2, 1, %g0 -84: - MOVE_SHORTCHUNK(o1, o0, 0x0c, g2, g3) - MOVE_SHORTCHUNK(o1, o0, 0x0a, g2, g3) - MOVE_SHORTCHUNK(o1, o0, 0x08, g2, g3) - MOVE_SHORTCHUNK(o1, o0, 0x06, g2, g3) - MOVE_SHORTCHUNK(o1, o0, 0x04, g2, g3) - MOVE_SHORTCHUNK(o1, o0, 0x02, g2, g3) - MOVE_SHORTCHUNK(o1, o0, 0x00, g2, g3) + MOVE_LAST_SHORTCHUNK(o1, o0, 0x0c, g2, g3) + MOVE_LAST_SHORTCHUNK(o1, o0, 0x0a, g2, g3) + MOVE_LAST_SHORTCHUNK(o1, o0, 0x08, g2, g3) + MOVE_LAST_SHORTCHUNK(o1, o0, 0x06, g2, g3) + MOVE_LAST_SHORTCHUNK(o1, o0, 0x04, g2, g3) + MOVE_LAST_SHORTCHUNK(o1, o0, 0x02, g2, g3) + MOVE_LAST_SHORTCHUNK(o1, o0, 0x00, g2, g3) short_table_end: - EXT(84b, short_table_end, 55f) be 1f nop EX(ldub [%o1], %g2, add %g0, 1) @@ -363,123 +387,8 @@ short_aligned_end: .section .fixup,#alloc,#execinstr .align 4 97: - mov %o2, %g3 -fixupretl: retl - mov %g3, %o0 - -/* exception routine sets %g2 to (broken_insn - first_insn)>>2 */ -50: -/* This magic counts how many bytes are left when crash in MOVE_BIGCHUNK - * happens. This is derived from the amount ldd reads, st stores, etc. - * x = g2 % 12; - * g3 = g1 + g7 - ((g2 / 12) * 32 + (x < 4) ? 0 : (x - 4) * 4); - * o0 += (g2 / 12) * 32; - */ - cmp %g2, 12 - add %o0, %g7, %o0 - bcs 1f - cmp %g2, 24 - bcs 2f - cmp %g2, 36 - bcs 3f - nop - sub %g2, 12, %g2 - sub %g7, 32, %g7 -3: sub %g2, 12, %g2 - sub %g7, 32, %g7 -2: sub %g2, 12, %g2 - sub %g7, 32, %g7 -1: cmp %g2, 4 - bcs,a 60f - clr %g2 - sub %g2, 4, %g2 - sll %g2, 2, %g2 -60: and %g1, 0x7f, %g3 - sub %o0, %g7, %o0 - add %g3, %g7, %g3 - ba fixupretl - sub %g3, %g2, %g3 -51: -/* i = 41 - g2; j = i % 6; - * g3 = (g1 & 15) + (i / 6) * 16 + (j < 4) ? (j + 1) * 4 : 16; - * o0 -= (i / 6) * 16 + 16; - */ - neg %g2 - and %g1, 0xf, %g1 - add %g2, 41, %g2 - add %o0, %g1, %o0 -1: cmp %g2, 6 - bcs,a 2f - cmp %g2, 4 - add %g1, 16, %g1 - b 1b - sub %g2, 6, %g2 -2: bcc,a 2f - mov 16, %g2 - inc %g2 - sll %g2, 2, %g2 -2: add %g1, %g2, %g3 - ba fixupretl - sub %o0, %g3, %o0 -52: -/* g3 = g1 + g7 - (g2 / 8) * 32 + (g2 & 4) ? (g2 & 3) * 8 : 0; - o0 += (g2 / 8) * 32 */ - andn %g2, 7, %g4 - add %o0, %g7, %o0 - andcc %g2, 4, %g0 - and %g2, 3, %g2 - sll %g4, 2, %g4 - sll %g2, 3, %g2 - bne 60b - sub %g7, %g4, %g7 - ba 60b - clr %g2 -53: -/* g3 = o3 + (o2 & 15) - (g2 & 8) - (g2 & 4) ? (g2 & 3) * 2 : 0; - o0 += (g2 & 8) */ - and %g2, 3, %g4 - andcc %g2, 4, %g0 - and %g2, 8, %g2 - sll %g4, 1, %g4 - be 1f - add %o0, %g2, %o0 - add %g2, %g4, %g2 -1: and %o2, 0xf, %g3 - add %g3, %o3, %g3 - ba fixupretl - sub %g3, %g2, %g3 -54: -/* g3 = o3 + (o2 & 15) - (g2 / 4) * 2 - (g2 & 2) ? (g2 & 1) : 0; - o0 += (g2 / 4) * 2 */ - srl %g2, 2, %o4 - and %g2, 1, %o5 - srl %g2, 1, %g2 - add %o4, %o4, %o4 - and %o5, %g2, %o5 - and %o2, 0xf, %o2 - add %o0, %o4, %o0 - sub %o3, %o5, %o3 - sub %o2, %o4, %o2 - ba fixupretl - add %o2, %o3, %g3 -55: -/* i = 27 - g2; - g3 = (o2 & 1) + i / 4 * 2 + !(i & 3); - o0 -= i / 4 * 2 + 1 */ - neg %g2 - and %o2, 1, %o2 - add %g2, 27, %g2 - srl %g2, 2, %o5 - andcc %g2, 3, %g0 - mov 1, %g2 - add %o5, %o5, %o5 - be,a 1f - clr %g2 -1: add %g2, %o5, %g3 - sub %o0, %g3, %o0 - ba fixupretl - add %g3, %o2, %g3 + mov %o2, %o0 .globl __copy_user_end __copy_user_end: |