| /* |
| * Copyright 2010 Tilera Corporation. All Rights Reserved. |
| * |
| * This program is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU General Public License |
| * as published by the Free Software Foundation, version 2. |
| * |
| * This program is distributed in the hope that it will be useful, but |
| * WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or |
| * NON INFRINGEMENT. See the GNU General Public License for |
| * more details. |
| */ |
| |
| #include <linux/linkage.h> |
| #include <asm/errno.h> |
| #include <asm/cache.h> |
| #include <arch/chip.h> |
| |
| /* Access user memory, but use MMU to avoid propagating kernel exceptions. */ |
| |
| .pushsection .fixup,"ax" |
| |
| get_user_fault: |
| { move r0, zero; move r1, zero } |
| { movei r2, -EFAULT; jrp lr } |
| ENDPROC(get_user_fault) |
| |
| put_user_fault: |
| { movei r0, -EFAULT; jrp lr } |
| ENDPROC(put_user_fault) |
| |
| .popsection |
| |
| /* |
| * __get_user_N functions take a pointer in r0, and return 0 in r2 |
| * on success, with the value in r0; or else -EFAULT in r2. |
| */ |
| #define __get_user_N(bytes, LOAD) \ |
| STD_ENTRY(__get_user_##bytes); \ |
| 1: { LOAD r0, r0; move r1, zero; move r2, zero }; \ |
| jrp lr; \ |
| STD_ENDPROC(__get_user_##bytes); \ |
| .pushsection __ex_table,"a"; \ |
| .word 1b, get_user_fault; \ |
| .popsection |
| |
| __get_user_N(1, lb_u) |
| __get_user_N(2, lh_u) |
| __get_user_N(4, lw) |
| |
| /* |
| * __get_user_8 takes a pointer in r0, and returns 0 in r2 |
| * on success, with the value in r0/r1; or else -EFAULT in r2. |
| */ |
| STD_ENTRY(__get_user_8); |
| 1: { lw r0, r0; addi r1, r0, 4 }; |
| 2: { lw r1, r1; move r2, zero }; |
| jrp lr; |
| STD_ENDPROC(__get_user_8); |
| .pushsection __ex_table,"a"; |
| .word 1b, get_user_fault; |
| .word 2b, get_user_fault; |
| .popsection |
| |
| /* |
| * __put_user_N functions take a value in r0 and a pointer in r1, |
| * and return 0 in r0 on success or -EFAULT on failure. |
| */ |
| #define __put_user_N(bytes, STORE) \ |
| STD_ENTRY(__put_user_##bytes); \ |
| 1: { STORE r1, r0; move r0, zero }; \ |
| jrp lr; \ |
| STD_ENDPROC(__put_user_##bytes); \ |
| .pushsection __ex_table,"a"; \ |
| .word 1b, put_user_fault; \ |
| .popsection |
| |
| __put_user_N(1, sb) |
| __put_user_N(2, sh) |
| __put_user_N(4, sw) |
| |
| /* |
| * __put_user_8 takes a value in r0/r1 and a pointer in r2, |
| * and returns 0 in r0 on success or -EFAULT on failure. |
| */ |
| STD_ENTRY(__put_user_8) |
| 1: { sw r2, r0; addi r2, r2, 4 } |
| 2: { sw r2, r1; move r0, zero } |
| jrp lr |
| STD_ENDPROC(__put_user_8) |
| .pushsection __ex_table,"a" |
| .word 1b, put_user_fault |
| .word 2b, put_user_fault |
| .popsection |
| |
| |
| /* |
| * strnlen_user_asm takes the pointer in r0, and the length bound in r1. |
| * It returns the length, including the terminating NUL, or zero on exception. |
| * If length is greater than the bound, returns one plus the bound. |
| */ |
| STD_ENTRY(strnlen_user_asm) |
| { bz r1, 2f; addi r3, r0, -1 } /* bias down to include NUL */ |
| 1: { lb_u r4, r0; addi r1, r1, -1 } |
| bz r4, 2f |
| { bnzt r1, 1b; addi r0, r0, 1 } |
| 2: { sub r0, r0, r3; jrp lr } |
| STD_ENDPROC(strnlen_user_asm) |
| .pushsection .fixup,"ax" |
| strnlen_user_fault: |
| { move r0, zero; jrp lr } |
| ENDPROC(strnlen_user_fault) |
| .section __ex_table,"a" |
| .word 1b, strnlen_user_fault |
| .popsection |
| |
| /* |
| * strncpy_from_user_asm takes the kernel target pointer in r0, |
| * the userspace source pointer in r1, and the length bound (including |
| * the trailing NUL) in r2. On success, it returns the string length |
| * (not including the trailing NUL), or -EFAULT on failure. |
| */ |
| STD_ENTRY(strncpy_from_user_asm) |
| { bz r2, 2f; move r3, r0 } |
| 1: { lb_u r4, r1; addi r1, r1, 1; addi r2, r2, -1 } |
| { sb r0, r4; addi r0, r0, 1 } |
| bz r2, 2f |
| bnzt r4, 1b |
| addi r0, r0, -1 /* don't count the trailing NUL */ |
| 2: { sub r0, r0, r3; jrp lr } |
| STD_ENDPROC(strncpy_from_user_asm) |
| .pushsection .fixup,"ax" |
| strncpy_from_user_fault: |
| { movei r0, -EFAULT; jrp lr } |
| ENDPROC(strncpy_from_user_fault) |
| .section __ex_table,"a" |
| .word 1b, strncpy_from_user_fault |
| .popsection |
| |
| /* |
| * clear_user_asm takes the user target address in r0 and the |
| * number of bytes to zero in r1. |
| * It returns the number of uncopiable bytes (hopefully zero) in r0. |
| * Note that we don't use a separate .fixup section here since we fall |
| * through into the "fixup" code as the last straight-line bundle anyway. |
| */ |
| STD_ENTRY(clear_user_asm) |
| { bz r1, 2f; or r2, r0, r1 } |
| andi r2, r2, 3 |
| bzt r2, .Lclear_aligned_user_asm |
| 1: { sb r0, zero; addi r0, r0, 1; addi r1, r1, -1 } |
| bnzt r1, 1b |
| 2: { move r0, r1; jrp lr } |
| .pushsection __ex_table,"a" |
| .word 1b, 2b |
| .popsection |
| |
| .Lclear_aligned_user_asm: |
| 1: { sw r0, zero; addi r0, r0, 4; addi r1, r1, -4 } |
| bnzt r1, 1b |
| 2: { move r0, r1; jrp lr } |
| STD_ENDPROC(clear_user_asm) |
| .pushsection __ex_table,"a" |
| .word 1b, 2b |
| .popsection |
| |
| /* |
| * flush_user_asm takes the user target address in r0 and the |
| * number of bytes to flush in r1. |
| * It returns the number of unflushable bytes (hopefully zero) in r0. |
| */ |
| STD_ENTRY(flush_user_asm) |
| bz r1, 2f |
| { movei r2, L2_CACHE_BYTES; add r1, r0, r1 } |
| { sub r2, zero, r2; addi r1, r1, L2_CACHE_BYTES-1 } |
| { and r0, r0, r2; and r1, r1, r2 } |
| { sub r1, r1, r0 } |
| 1: { flush r0; addi r1, r1, -CHIP_FLUSH_STRIDE() } |
| { addi r0, r0, CHIP_FLUSH_STRIDE(); bnzt r1, 1b } |
| 2: { move r0, r1; jrp lr } |
| STD_ENDPROC(flush_user_asm) |
| .pushsection __ex_table,"a" |
| .word 1b, 2b |
| .popsection |
| |
| /* |
| * inv_user_asm takes the user target address in r0 and the |
| * number of bytes to invalidate in r1. |
| * It returns the number of not inv'able bytes (hopefully zero) in r0. |
| */ |
| STD_ENTRY(inv_user_asm) |
| bz r1, 2f |
| { movei r2, L2_CACHE_BYTES; add r1, r0, r1 } |
| { sub r2, zero, r2; addi r1, r1, L2_CACHE_BYTES-1 } |
| { and r0, r0, r2; and r1, r1, r2 } |
| { sub r1, r1, r0 } |
| 1: { inv r0; addi r1, r1, -CHIP_INV_STRIDE() } |
| { addi r0, r0, CHIP_INV_STRIDE(); bnzt r1, 1b } |
| 2: { move r0, r1; jrp lr } |
| STD_ENDPROC(inv_user_asm) |
| .pushsection __ex_table,"a" |
| .word 1b, 2b |
| .popsection |
| |
| /* |
| * finv_user_asm takes the user target address in r0 and the |
| * number of bytes to flush-invalidate in r1. |
| * It returns the number of not finv'able bytes (hopefully zero) in r0. |
| */ |
| STD_ENTRY(finv_user_asm) |
| bz r1, 2f |
| { movei r2, L2_CACHE_BYTES; add r1, r0, r1 } |
| { sub r2, zero, r2; addi r1, r1, L2_CACHE_BYTES-1 } |
| { and r0, r0, r2; and r1, r1, r2 } |
| { sub r1, r1, r0 } |
| 1: { finv r0; addi r1, r1, -CHIP_FINV_STRIDE() } |
| { addi r0, r0, CHIP_FINV_STRIDE(); bnzt r1, 1b } |
| 2: { move r0, r1; jrp lr } |
| STD_ENDPROC(finv_user_asm) |
| .pushsection __ex_table,"a" |
| .word 1b, 2b |
| .popsection |
