Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * linux/arch/arm/kernel/entry-common.S |
| 3 | * |
| 4 | * Copyright (C) 2000 Russell King |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or modify |
| 7 | * it under the terms of the GNU General Public License version 2 as |
| 8 | * published by the Free Software Foundation. |
| 9 | */ |
| 10 | #include <linux/config.h> |
| 11 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 12 | #include <asm/unistd.h> |
| 13 | |
| 14 | #include "entry-header.S" |
| 15 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 16 | |
| 17 | .align 5 |
| 18 | /* |
| 19 | * This is the fast syscall return path. We do as little as |
| 20 | * possible here, and this includes saving r0 back into the SVC |
| 21 | * stack. |
| 22 | */ |
| 23 | ret_fast_syscall: |
Russell King | 1ec42c0 | 2005-04-26 15:18:26 +0100 | [diff] [blame] | 24 | disable_irq @ disable interrupts |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 25 | ldr r1, [tsk, #TI_FLAGS] |
| 26 | tst r1, #_TIF_WORK_MASK |
| 27 | bne fast_work_pending |
Russell King | f4dc9a4 | 2005-04-26 15:20:34 +0100 | [diff] [blame] | 28 | |
| 29 | @ fast_restore_user_regs |
| 30 | ldr r1, [sp, #S_OFF + S_PSR] @ get calling cpsr |
| 31 | ldr lr, [sp, #S_OFF + S_PC]! @ get pc |
| 32 | msr spsr_cxsf, r1 @ save in spsr_svc |
| 33 | ldmdb sp, {r1 - lr}^ @ get calling r1 - lr |
| 34 | mov r0, r0 |
| 35 | add sp, sp, #S_FRAME_SIZE - S_PC |
| 36 | movs pc, lr @ return & move spsr_svc into cpsr |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 37 | |
| 38 | /* |
| 39 | * Ok, we need to do extra processing, enter the slow path. |
| 40 | */ |
| 41 | fast_work_pending: |
| 42 | str r0, [sp, #S_R0+S_OFF]! @ returned r0 |
| 43 | work_pending: |
| 44 | tst r1, #_TIF_NEED_RESCHED |
| 45 | bne work_resched |
| 46 | tst r1, #_TIF_NOTIFY_RESUME | _TIF_SIGPENDING |
| 47 | beq no_work_pending |
| 48 | mov r0, sp @ 'regs' |
| 49 | mov r2, why @ 'syscall' |
| 50 | bl do_notify_resume |
Daniel Jacobowitz | a6c61e9 | 2005-11-19 10:01:07 +0000 | [diff] [blame] | 51 | b ret_slow_syscall @ Check work again |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 52 | |
| 53 | work_resched: |
| 54 | bl schedule |
| 55 | /* |
| 56 | * "slow" syscall return path. "why" tells us if this was a real syscall. |
| 57 | */ |
| 58 | ENTRY(ret_to_user) |
| 59 | ret_slow_syscall: |
Russell King | 1ec42c0 | 2005-04-26 15:18:26 +0100 | [diff] [blame] | 60 | disable_irq @ disable interrupts |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 61 | ldr r1, [tsk, #TI_FLAGS] |
| 62 | tst r1, #_TIF_WORK_MASK |
| 63 | bne work_pending |
| 64 | no_work_pending: |
Russell King | f4dc9a4 | 2005-04-26 15:20:34 +0100 | [diff] [blame] | 65 | @ slow_restore_user_regs |
| 66 | ldr r1, [sp, #S_PSR] @ get calling cpsr |
| 67 | ldr lr, [sp, #S_PC]! @ get pc |
| 68 | msr spsr_cxsf, r1 @ save in spsr_svc |
| 69 | ldmdb sp, {r0 - lr}^ @ get calling r1 - lr |
| 70 | mov r0, r0 |
| 71 | add sp, sp, #S_FRAME_SIZE - S_PC |
| 72 | movs pc, lr @ return & move spsr_svc into cpsr |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 73 | |
| 74 | /* |
| 75 | * This is how we return from a fork. |
| 76 | */ |
| 77 | ENTRY(ret_from_fork) |
| 78 | bl schedule_tail |
| 79 | get_thread_info tsk |
| 80 | ldr r1, [tsk, #TI_FLAGS] @ check for syscall tracing |
| 81 | mov why, #1 |
| 82 | tst r1, #_TIF_SYSCALL_TRACE @ are we tracing syscalls? |
| 83 | beq ret_slow_syscall |
| 84 | mov r1, sp |
| 85 | mov r0, #1 @ trace exit [IP = 1] |
| 86 | bl syscall_trace |
| 87 | b ret_slow_syscall |
| 88 | |
| 89 | |
| 90 | #include "calls.S" |
| 91 | |
| 92 | /*============================================================================= |
| 93 | * SWI handler |
| 94 | *----------------------------------------------------------------------------- |
| 95 | */ |
| 96 | |
| 97 | /* If we're optimising for StrongARM the resulting code won't |
| 98 | run on an ARM7 and we can save a couple of instructions. |
| 99 | --pb */ |
| 100 | #ifdef CONFIG_CPU_ARM710 |
Nicolas Pitre | 3f2829a | 2006-01-14 16:31:29 +0000 | [diff] [blame] | 101 | #define A710(code...) code |
| 102 | .Larm710bug: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 103 | ldmia sp, {r0 - lr}^ @ Get calling r0 - lr |
| 104 | mov r0, r0 |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 105 | add sp, sp, #S_FRAME_SIZE |
Nicolas Pitre | 60ac133 | 2005-10-12 19:51:24 +0100 | [diff] [blame] | 106 | subs pc, lr, #4 |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 107 | #else |
Nicolas Pitre | 3f2829a | 2006-01-14 16:31:29 +0000 | [diff] [blame] | 108 | #define A710(code...) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 109 | #endif |
| 110 | |
| 111 | .align 5 |
| 112 | ENTRY(vector_swi) |
Russell King | f4dc9a4 | 2005-04-26 15:20:34 +0100 | [diff] [blame] | 113 | sub sp, sp, #S_FRAME_SIZE |
| 114 | stmia sp, {r0 - r12} @ Calling r0 - r12 |
| 115 | add r8, sp, #S_PC |
| 116 | stmdb r8, {sp, lr}^ @ Calling sp, lr |
| 117 | mrs r8, spsr @ called from non-FIQ mode, so ok. |
| 118 | str lr, [sp, #S_PC] @ Save calling PC |
| 119 | str r8, [sp, #S_PSR] @ Save CPSR |
| 120 | str r0, [sp, #S_OLD_R0] @ Save OLD_R0 |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 121 | zero_fp |
Russell King | e0f9f4a | 2005-04-26 15:19:24 +0100 | [diff] [blame] | 122 | |
| 123 | /* |
| 124 | * Get the system call number. |
| 125 | */ |
Nicolas Pitre | 3f2829a | 2006-01-14 16:31:29 +0000 | [diff] [blame] | 126 | #if defined(CONFIG_AEABI) |
| 127 | |
| 128 | @ syscall number is in scno (r7) already. |
| 129 | |
| 130 | A710( ldr ip, [lr, #-4] @ get SWI instruction ) |
| 131 | A710( and ip, ip, #0x0f000000 @ check for SWI ) |
| 132 | A710( teq ip, #0x0f000000 ) |
| 133 | A710( bne .Larm710bug ) |
| 134 | #elif defined(CONFIG_ARM_THUMB) |
Russell King | e0f9f4a | 2005-04-26 15:19:24 +0100 | [diff] [blame] | 135 | tst r8, #PSR_T_BIT @ this is SPSR from save_user_regs |
| 136 | addne scno, r7, #__NR_SYSCALL_BASE @ put OS number in |
| 137 | ldreq scno, [lr, #-4] |
| 138 | #else |
| 139 | ldr scno, [lr, #-4] @ get SWI instruction |
Nicolas Pitre | 3f2829a | 2006-01-14 16:31:29 +0000 | [diff] [blame] | 140 | A710( and ip, scno, #0x0f000000 @ check for SWI ) |
| 141 | A710( teq ip, #0x0f000000 ) |
| 142 | A710( bne .Larm710bug ) |
Russell King | e0f9f4a | 2005-04-26 15:19:24 +0100 | [diff] [blame] | 143 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 144 | |
| 145 | #ifdef CONFIG_ALIGNMENT_TRAP |
| 146 | ldr ip, __cr_alignment |
| 147 | ldr ip, [ip] |
| 148 | mcr p15, 0, ip, c1, c0 @ update control register |
| 149 | #endif |
Russell King | 1ec42c0 | 2005-04-26 15:18:26 +0100 | [diff] [blame] | 150 | enable_irq |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 151 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 152 | get_thread_info tsk |
| 153 | ldr ip, [tsk, #TI_FLAGS] @ check for syscall tracing |
Nicolas Pitre | 3f2829a | 2006-01-14 16:31:29 +0000 | [diff] [blame] | 154 | #ifndef CONFIG_AEABI |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 155 | bic scno, scno, #0xff000000 @ mask off SWI op-code |
Russell King | e0f9f4a | 2005-04-26 15:19:24 +0100 | [diff] [blame] | 156 | eor scno, scno, #__NR_SYSCALL_BASE @ check OS number |
Nicolas Pitre | 3f2829a | 2006-01-14 16:31:29 +0000 | [diff] [blame] | 157 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 158 | adr tbl, sys_call_table @ load syscall table pointer |
Nicolas Pitre | 3f2829a | 2006-01-14 16:31:29 +0000 | [diff] [blame] | 159 | stmdb sp!, {r4, r5} @ push fifth and sixth args |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 160 | tst ip, #_TIF_SYSCALL_TRACE @ are we tracing syscalls? |
| 161 | bne __sys_trace |
| 162 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 163 | cmp scno, #NR_syscalls @ check upper syscall limit |
Nicolas Pitre | 3f2829a | 2006-01-14 16:31:29 +0000 | [diff] [blame] | 164 | adr lr, ret_fast_syscall @ return address |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 165 | ldrcc pc, [tbl, scno, lsl #2] @ call sys_* routine |
| 166 | |
| 167 | add r1, sp, #S_OFF |
| 168 | 2: mov why, #0 @ no longer a real syscall |
Russell King | e0f9f4a | 2005-04-26 15:19:24 +0100 | [diff] [blame] | 169 | cmp scno, #(__ARM_NR_BASE - __NR_SYSCALL_BASE) |
| 170 | eor r0, scno, #__NR_SYSCALL_BASE @ put OS number back |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 171 | bcs arm_syscall |
| 172 | b sys_ni_syscall @ not private func |
| 173 | |
| 174 | /* |
| 175 | * This is the really slow path. We're going to be doing |
| 176 | * context switches, and waiting for our parent to respond. |
| 177 | */ |
| 178 | __sys_trace: |
| 179 | add r1, sp, #S_OFF |
| 180 | mov r0, #0 @ trace entry [IP = 0] |
| 181 | bl syscall_trace |
| 182 | |
| 183 | adr lr, __sys_trace_return @ return address |
| 184 | add r1, sp, #S_R0 + S_OFF @ pointer to regs |
| 185 | cmp scno, #NR_syscalls @ check upper syscall limit |
| 186 | ldmccia r1, {r0 - r3} @ have to reload r0 - r3 |
| 187 | ldrcc pc, [tbl, scno, lsl #2] @ call sys_* routine |
| 188 | b 2b |
| 189 | |
| 190 | __sys_trace_return: |
| 191 | str r0, [sp, #S_R0 + S_OFF]! @ save returned r0 |
| 192 | mov r1, sp |
| 193 | mov r0, #1 @ trace exit [IP = 1] |
| 194 | bl syscall_trace |
| 195 | b ret_slow_syscall |
| 196 | |
| 197 | .align 5 |
| 198 | #ifdef CONFIG_ALIGNMENT_TRAP |
| 199 | .type __cr_alignment, #object |
| 200 | __cr_alignment: |
| 201 | .word cr_alignment |
| 202 | #endif |
| 203 | |
| 204 | .type sys_call_table, #object |
| 205 | ENTRY(sys_call_table) |
| 206 | #include "calls.S" |
| 207 | |
| 208 | /*============================================================================ |
| 209 | * Special system call wrappers |
| 210 | */ |
| 211 | @ r0 = syscall number |
Russell King | 567bd98 | 2005-12-17 15:25:42 +0000 | [diff] [blame] | 212 | @ r8 = syscall table |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 213 | .type sys_syscall, #function |
| 214 | sys_syscall: |
Nicolas Pitre | 3f2829a | 2006-01-14 16:31:29 +0000 | [diff] [blame] | 215 | #ifndef CONFIG_AEABI |
Russell King | e0f9f4a | 2005-04-26 15:19:24 +0100 | [diff] [blame] | 216 | eor scno, r0, #__NR_SYSCALL_BASE |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 217 | cmp scno, #__NR_syscall - __NR_SYSCALL_BASE |
| 218 | cmpne scno, #NR_syscalls @ check range |
| 219 | stmloia sp, {r5, r6} @ shuffle args |
| 220 | movlo r0, r1 |
| 221 | movlo r1, r2 |
| 222 | movlo r2, r3 |
| 223 | movlo r3, r4 |
| 224 | ldrlo pc, [tbl, scno, lsl #2] |
Nicolas Pitre | 3f2829a | 2006-01-14 16:31:29 +0000 | [diff] [blame] | 225 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 226 | b sys_ni_syscall |
| 227 | |
| 228 | sys_fork_wrapper: |
| 229 | add r0, sp, #S_OFF |
| 230 | b sys_fork |
| 231 | |
| 232 | sys_vfork_wrapper: |
| 233 | add r0, sp, #S_OFF |
| 234 | b sys_vfork |
| 235 | |
| 236 | sys_execve_wrapper: |
| 237 | add r3, sp, #S_OFF |
| 238 | b sys_execve |
| 239 | |
| 240 | sys_clone_wrapper: |
| 241 | add ip, sp, #S_OFF |
| 242 | str ip, [sp, #4] |
| 243 | b sys_clone |
| 244 | |
| 245 | sys_sigsuspend_wrapper: |
| 246 | add r3, sp, #S_OFF |
| 247 | b sys_sigsuspend |
| 248 | |
| 249 | sys_rt_sigsuspend_wrapper: |
| 250 | add r2, sp, #S_OFF |
| 251 | b sys_rt_sigsuspend |
| 252 | |
| 253 | sys_sigreturn_wrapper: |
| 254 | add r0, sp, #S_OFF |
| 255 | b sys_sigreturn |
| 256 | |
| 257 | sys_rt_sigreturn_wrapper: |
| 258 | add r0, sp, #S_OFF |
| 259 | b sys_rt_sigreturn |
| 260 | |
| 261 | sys_sigaltstack_wrapper: |
| 262 | ldr r2, [sp, #S_OFF + S_SP] |
| 263 | b do_sigaltstack |
| 264 | |
Nicolas Pitre | 713c481 | 2006-01-14 16:35:03 +0000 | [diff] [blame^] | 265 | sys_statfs64_wrapper: |
| 266 | teq r1, #88 |
| 267 | moveq r1, #84 |
| 268 | b sys_statfs64 |
| 269 | |
| 270 | sys_fstatfs64_wrapper: |
| 271 | teq r1, #88 |
| 272 | moveq r1, #84 |
| 273 | b sys_fstatfs64 |
| 274 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 275 | /* |
| 276 | * Note: off_4k (r5) is always units of 4K. If we can't do the requested |
| 277 | * offset, we return EINVAL. |
| 278 | */ |
| 279 | sys_mmap2: |
| 280 | #if PAGE_SHIFT > 12 |
| 281 | tst r5, #PGOFF_MASK |
| 282 | moveq r5, r5, lsr #PAGE_SHIFT - 12 |
| 283 | streq r5, [sp, #4] |
| 284 | beq do_mmap2 |
| 285 | mov r0, #-EINVAL |
| 286 | RETINSTR(mov,pc, lr) |
| 287 | #else |
| 288 | str r5, [sp, #4] |
| 289 | b do_mmap2 |
| 290 | #endif |