| Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Access to the shared data page by the vDSO & syscall map |
| 3 | * |
| 4 | * Copyright (C) 2004 Benjamin Herrenschmuidt (benh@kernel.crashing.org), IBM Corp. |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or |
| 7 | * modify it under the terms of the GNU General Public License |
| 8 | * as published by the Free Software Foundation; either version |
| 9 | * 2 of the License, or (at your option) any later version. |
| 10 | */ |
| 11 | |
| 12 | #include <linux/config.h> |
| 13 | #include <asm/processor.h> |
| 14 | #include <asm/ppc_asm.h> |
| Sam Ravnborg | 0013a85 | 2005-09-09 20:57:26 +0200 | [diff] [blame] | 15 | #include <asm/asm-offsets.h> |
| Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 16 | #include <asm/unistd.h> |
| 17 | #include <asm/vdso.h> |
| 18 | |
| 19 | .text |
| 20 | V_FUNCTION_BEGIN(__get_datapage) |
| 21 | .cfi_startproc |
| 22 | /* We don't want that exposed or overridable as we want other objects |
| 23 | * to be able to bl directly to here |
| 24 | */ |
| 25 | .protected __get_datapage |
| 26 | .hidden __get_datapage |
| 27 | |
| 28 | mflr r0 |
| 29 | .cfi_register lr,r0 |
| 30 | |
| 31 | bcl 20,31,1f |
| 32 | .global __kernel_datapage_offset; |
| 33 | __kernel_datapage_offset: |
| 34 | .long 0 |
| 35 | 1: |
| 36 | mflr r3 |
| 37 | mtlr r0 |
| 38 | lwz r0,0(r3) |
| 39 | add r3,r0,r3 |
| 40 | blr |
| 41 | .cfi_endproc |
| 42 | V_FUNCTION_END(__get_datapage) |
| 43 | |
| 44 | /* |
| 45 | * void *__kernel_get_syscall_map(unsigned int *syscall_count) ; |
| 46 | * |
| 47 | * returns a pointer to the syscall map. the map is agnostic to the |
| 48 | * size of "long", unlike kernel bitops, it stores bits from top to |
| 49 | * bottom so that memory actually contains a linear bitmap |
| 50 | * check for syscall N by testing bit (0x80000000 >> (N & 0x1f)) of |
| 51 | * 32 bits int at N >> 5. |
| 52 | */ |
| 53 | V_FUNCTION_BEGIN(__kernel_get_syscall_map) |
| 54 | .cfi_startproc |
| 55 | mflr r12 |
| 56 | .cfi_register lr,r12 |
| Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 57 | mr r4,r3 |
| 58 | bl V_LOCAL_FUNC(__get_datapage) |
| 59 | mtlr r12 |
| 60 | addi r3,r3,CFG_SYSCALL_MAP64 |
| 61 | cmpli cr0,r4,0 |
| Benjamin Herrenschmidt | 5d66da3 | 2005-11-16 13:54:32 +1100 | [diff] [blame] | 62 | crclr cr0*4+so |
| Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 63 | beqlr |
| 64 | li r0,__NR_syscalls |
| 65 | stw r0,0(r4) |
| 66 | blr |
| 67 | .cfi_endproc |
| 68 | V_FUNCTION_END(__kernel_get_syscall_map) |
| Benjamin Herrenschmidt | a7f290d | 2005-11-11 21:15:21 +1100 | [diff] [blame] | 69 | |
| 70 | |
| 71 | /* |
| 72 | * void unsigned long __kernel_get_tbfreq(void); |
| 73 | * |
| 74 | * returns the timebase frequency in HZ |
| 75 | */ |
| 76 | V_FUNCTION_BEGIN(__kernel_get_tbfreq) |
| 77 | .cfi_startproc |
| 78 | mflr r12 |
| 79 | .cfi_register lr,r12 |
| 80 | bl V_LOCAL_FUNC(__get_datapage) |
| 81 | ld r3,CFG_TB_TICKS_PER_SEC(r3) |
| 82 | mtlr r12 |
| Benjamin Herrenschmidt | 5d66da3 | 2005-11-16 13:54:32 +1100 | [diff] [blame] | 83 | crclr cr0*4+so |
| Benjamin Herrenschmidt | 0c37ec2 | 2005-11-14 14:55:58 +1100 | [diff] [blame] | 84 | blr |
| Benjamin Herrenschmidt | a7f290d | 2005-11-11 21:15:21 +1100 | [diff] [blame] | 85 | .cfi_endproc |
| 86 | V_FUNCTION_END(__kernel_get_tbfreq) |