| /* |
| * arch/alpha/lib/copy_user.S |
| * |
| * Copy to/from user space, handling exceptions as we go.. This |
| * isn't exactly pretty. |
| * |
| * This is essentially the same as "memcpy()", but with a few twists. |
| * Notably, we have to make sure that $0 is always up-to-date and |
| * contains the right "bytes left to copy" value (and that it is updated |
| * only _after_ a successful copy). There is also some rather minor |
| * exception setup stuff.. |
| */ |
| |
| #include <asm/export.h> |
| |
| /* Allow an exception for an insn; exit if we get one. */ |
| #define EXI(x,y...) \ |
| 99: x,##y; \ |
| .section __ex_table,"a"; \ |
| .long 99b - .; \ |
| lda $31, $exitin-99b($31); \ |
| .previous |
| |
| #define EXO(x,y...) \ |
| 99: x,##y; \ |
| .section __ex_table,"a"; \ |
| .long 99b - .; \ |
| lda $31, $exitout-99b($31); \ |
| .previous |
| |
| .set noat |
| .align 4 |
| .globl __copy_user |
| .ent __copy_user |
| __copy_user: |
| .prologue 0 |
| and $18,$18,$0 |
| and $16,7,$3 |
| beq $0,$35 |
| beq $3,$36 |
| subq $3,8,$3 |
| .align 4 |
| $37: |
| EXI( ldq_u $1,0($17) ) |
| EXO( ldq_u $2,0($16) ) |
| extbl $1,$17,$1 |
| mskbl $2,$16,$2 |
| insbl $1,$16,$1 |
| addq $3,1,$3 |
| bis $1,$2,$1 |
| EXO( stq_u $1,0($16) ) |
| subq $0,1,$0 |
| addq $16,1,$16 |
| addq $17,1,$17 |
| beq $0,$41 |
| bne $3,$37 |
| $36: |
| and $17,7,$1 |
| bic $0,7,$4 |
| beq $1,$43 |
| beq $4,$48 |
| EXI( ldq_u $3,0($17) ) |
| .align 4 |
| $50: |
| EXI( ldq_u $2,8($17) ) |
| subq $4,8,$4 |
| extql $3,$17,$3 |
| extqh $2,$17,$1 |
| bis $3,$1,$1 |
| EXO( stq $1,0($16) ) |
| addq $17,8,$17 |
| subq $0,8,$0 |
| addq $16,8,$16 |
| bis $2,$2,$3 |
| bne $4,$50 |
| $48: |
| beq $0,$41 |
| .align 4 |
| $57: |
| EXI( ldq_u $1,0($17) ) |
| EXO( ldq_u $2,0($16) ) |
| extbl $1,$17,$1 |
| mskbl $2,$16,$2 |
| insbl $1,$16,$1 |
| bis $1,$2,$1 |
| EXO( stq_u $1,0($16) ) |
| subq $0,1,$0 |
| addq $16,1,$16 |
| addq $17,1,$17 |
| bne $0,$57 |
| br $31,$41 |
| .align 4 |
| $43: |
| beq $4,$65 |
| .align 4 |
| $66: |
| EXI( ldq $1,0($17) ) |
| subq $4,8,$4 |
| EXO( stq $1,0($16) ) |
| addq $17,8,$17 |
| subq $0,8,$0 |
| addq $16,8,$16 |
| bne $4,$66 |
| $65: |
| beq $0,$41 |
| EXI( ldq $2,0($17) ) |
| EXO( ldq $1,0($16) ) |
| mskql $2,$0,$2 |
| mskqh $1,$0,$1 |
| bis $2,$1,$2 |
| EXO( stq $2,0($16) ) |
| bis $31,$31,$0 |
| $41: |
| $35: |
| $exitin: |
| $exitout: |
| ret $31,($26),1 |
| |
| .end __copy_user |
| EXPORT_SYMBOL(__copy_user) |