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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
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 */
Linus Torvalds1da177e2005-04-16 15:20:36 -070010
Linus Torvalds1da177e2005-04-16 15:20:36 -070011#include <asm/unistd.h>
Abhishek Sagar395a59d2008-06-21 23:47:27 +053012#include <asm/ftrace.h>
Catalin Marinasc4c57162009-02-16 11:42:09 +010013#include <asm/unwind.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070014
Rob Herring13a5045d2012-02-07 09:28:22 -060015#ifdef CONFIG_NEED_RET_TO_USER
16#include <mach/entry-macro.S>
17#else
18 .macro arch_ret_to_user, tmp1, tmp2
19 .endm
20#endif
21
Linus Torvalds1da177e2005-04-16 15:20:36 -070022#include "entry-header.S"
23
Linus Torvalds1da177e2005-04-16 15:20:36 -070024
25 .align 5
26/*
27 * This is the fast syscall return path. We do as little as
28 * possible here, and this includes saving r0 back into the SVC
29 * stack.
30 */
31ret_fast_syscall:
Catalin Marinasc4c57162009-02-16 11:42:09 +010032 UNWIND(.fnstart )
33 UNWIND(.cantunwind )
Russell King1ec42c02005-04-26 15:18:26 +010034 disable_irq @ disable interrupts
Linus Torvalds1da177e2005-04-16 15:20:36 -070035 ldr r1, [tsk, #TI_FLAGS]
36 tst r1, #_TIF_WORK_MASK
37 bne fast_work_pending
Todd Android Poynord13e5ed2010-12-23 01:52:44 +010038#if defined(CONFIG_IRQSOFF_TRACER)
39 asm_trace_hardirqs_on
40#endif
Russell Kingf4dc9a42005-04-26 15:20:34 +010041
Dan Williamsf80dff92007-02-16 22:16:32 +010042 /* perform architecture specific actions before user return */
43 arch_ret_to_user r1, lr
44
Catalin Marinasb86040a2009-07-24 12:32:54 +010045 restore_user_regs fast = 1, offset = S_OFF
Catalin Marinasc4c57162009-02-16 11:42:09 +010046 UNWIND(.fnend )
Linus Torvalds1da177e2005-04-16 15:20:36 -070047
48/*
49 * Ok, we need to do extra processing, enter the slow path.
50 */
51fast_work_pending:
52 str r0, [sp, #S_R0+S_OFF]! @ returned r0
53work_pending:
Linus Torvalds1da177e2005-04-16 15:20:36 -070054 mov r0, sp @ 'regs'
55 mov r2, why @ 'syscall'
Al Viro0a267fa2012-07-19 17:47:55 +010056 bl do_work_pending
Al Viro66285212012-07-19 17:48:50 +010057 cmp r0, #0
Al Viro81783782012-07-19 17:48:21 +010058 beq no_work_pending
Al Viro66285212012-07-19 17:48:50 +010059 movlt scno, #(__NR_restart_syscall - __NR_SYSCALL_BASE)
Al Viro81783782012-07-19 17:48:21 +010060 ldmia sp, {r0 - r6} @ have to reload r0 - r6
61 b local_restart @ ... and off we go
62
Linus Torvalds1da177e2005-04-16 15:20:36 -070063/*
64 * "slow" syscall return path. "why" tells us if this was a real syscall.
65 */
66ENTRY(ret_to_user)
67ret_slow_syscall:
Russell King1ec42c02005-04-26 15:18:26 +010068 disable_irq @ disable interrupts
Ming Lei9fc25522011-06-05 02:24:58 +010069ENTRY(ret_to_user_from_irq)
Linus Torvalds1da177e2005-04-16 15:20:36 -070070 ldr r1, [tsk, #TI_FLAGS]
71 tst r1, #_TIF_WORK_MASK
72 bne work_pending
73no_work_pending:
Todd Android Poynord13e5ed2010-12-23 01:52:44 +010074#if defined(CONFIG_IRQSOFF_TRACER)
75 asm_trace_hardirqs_on
76#endif
Dan Williamsf80dff92007-02-16 22:16:32 +010077 /* perform architecture specific actions before user return */
78 arch_ret_to_user r1, lr
79
Catalin Marinasb86040a2009-07-24 12:32:54 +010080 restore_user_regs fast = 0, offset = 0
Ming Lei9fc25522011-06-05 02:24:58 +010081ENDPROC(ret_to_user_from_irq)
Catalin Marinas93ed3972008-08-28 11:22:32 +010082ENDPROC(ret_to_user)
Linus Torvalds1da177e2005-04-16 15:20:36 -070083
84/*
85 * This is how we return from a fork.
86 */
87ENTRY(ret_from_fork)
88 bl schedule_tail
Al Viro9fff2fa2012-10-10 22:23:29 -040089 cmp r5, #0
90 movne r0, r4
Russell King68687c82012-10-15 00:16:49 +010091 adrne lr, BSYM(1f)
Al Viro9fff2fa2012-10-10 22:23:29 -040092 movne pc, r5
Russell King68687c82012-10-15 00:16:49 +0100931: get_thread_info tsk
Linus Torvalds1da177e2005-04-16 15:20:36 -070094 b ret_slow_syscall
Catalin Marinas93ed3972008-08-28 11:22:32 +010095ENDPROC(ret_from_fork)
Linus Torvalds1da177e2005-04-16 15:20:36 -070096
Al Virofa1b4f92006-01-19 12:57:01 +000097 .equ NR_syscalls,0
98#define CALL(x) .equ NR_syscalls,NR_syscalls+1
Linus Torvalds1da177e2005-04-16 15:20:36 -070099#include "calls.S"
Wade Farnsworth1f66e062012-09-07 18:18:25 +0100100
101/*
102 * Ensure that the system call table is equal to __NR_syscalls,
103 * which is the value the rest of the system sees
104 */
105.ifne NR_syscalls - __NR_syscalls
106.error "__NR_syscalls is not equal to the size of the syscall table"
107.endif
108
Al Virofa1b4f92006-01-19 12:57:01 +0000109#undef CALL
110#define CALL(x) .long x
Linus Torvalds1da177e2005-04-16 15:20:36 -0700111
Steven Rostedt606576c2008-10-06 19:06:12 -0400112#ifdef CONFIG_FUNCTION_TRACER
Rabin Vincent686ff222010-08-03 17:09:40 +0100113/*
114 * When compiling with -pg, gcc inserts a call to the mcount routine at the
115 * start of every function. In mcount, apart from the function's address (in
116 * lr), we need to get hold of the function's caller's address.
117 *
118 * Older GCCs (pre-4.4) inserted a call to a routine called mcount like this:
119 *
120 * bl mcount
121 *
122 * These versions have the limitation that in order for the mcount routine to
123 * be able to determine the function's caller's address, an APCS-style frame
124 * pointer (which is set up with something like the code below) is required.
125 *
126 * mov ip, sp
127 * push {fp, ip, lr, pc}
128 * sub fp, ip, #4
129 *
130 * With EABI, these frame pointers are not available unless -mapcs-frame is
131 * specified, and if building as Thumb-2, not even then.
132 *
133 * Newer GCCs (4.4+) solve this problem by introducing a new version of mcount,
134 * with call sites like:
135 *
136 * push {lr}
137 * bl __gnu_mcount_nc
138 *
139 * With these compilers, frame pointers are not necessary.
140 *
141 * mcount can be thought of as a function called in the middle of a subroutine
142 * call. As such, it needs to be transparent for both the caller and the
143 * callee: the original lr needs to be restored when leaving mcount, and no
144 * registers should be clobbered. (In the __gnu_mcount_nc implementation, we
145 * clobber the ip register. This is OK because the ARM calling convention
146 * allows it to be clobbered in subroutines and doesn't use it to hold
147 * parameters.)
Rabin Vincent3b6c2232010-08-10 19:43:28 +0100148 *
149 * When using dynamic ftrace, we patch out the mcount call by a "mov r0, r0"
150 * for the mcount case, and a "pop {lr}" for the __gnu_mcount_nc case (see
151 * arch/arm/kernel/ftrace.c).
Rabin Vincent686ff222010-08-03 17:09:40 +0100152 */
Rabin Vincent09bfafa2010-08-10 19:32:37 +0100153
154#ifndef CONFIG_OLD_MCOUNT
155#if (__GNUC__ < 4 || (__GNUC__ == 4 && __GNUC_MINOR__ < 4))
156#error Ftrace requires CONFIG_FRAME_POINTER=y with GCC older than 4.4.0.
157#endif
158#endif
159
Rabin Vincentd68133b2012-01-24 16:52:52 +0100160.macro mcount_adjust_addr rd, rn
161 bic \rd, \rn, #1 @ clear the Thumb bit if present
162 sub \rd, \rd, #MCOUNT_INSN_SIZE
163.endm
164
Rabin Vincentd3b9dc92010-10-07 17:39:47 +0530165.macro __mcount suffix
166 mcount_enter
Rabin Vincent28e192d2010-08-03 17:08:09 +0100167 ldr r0, =ftrace_trace_function
168 ldr r2, [r0]
Rabin Vincenta3ba87a2010-08-10 19:37:21 +0100169 adr r0, .Lftrace_stub
Rabin Vincent28e192d2010-08-03 17:08:09 +0100170 cmp r0, r2
Rabin Vincentd3b9dc92010-10-07 17:39:47 +0530171 bne 1f
Uwe Kleine-König181f8172009-08-13 20:38:16 +0200172
Tim Bird376cfa82010-10-09 22:24:38 +0530173#ifdef CONFIG_FUNCTION_GRAPH_TRACER
174 ldr r1, =ftrace_graph_return
175 ldr r2, [r1]
176 cmp r0, r2
177 bne ftrace_graph_caller\suffix
178
179 ldr r1, =ftrace_graph_entry
180 ldr r2, [r1]
181 ldr r0, =ftrace_graph_entry_stub
182 cmp r0, r2
183 bne ftrace_graph_caller\suffix
184#endif
185
Rabin Vincentd3b9dc92010-10-07 17:39:47 +0530186 mcount_exit
Uwe Kleine-König181f8172009-08-13 20:38:16 +0200187
Rabin Vincentd3b9dc92010-10-07 17:39:47 +05301881: mcount_get_lr r1 @ lr of instrumented func
Rabin Vincentd68133b2012-01-24 16:52:52 +0100189 mcount_adjust_addr r0, lr @ instrumented function
Rabin Vincentd3b9dc92010-10-07 17:39:47 +0530190 adr lr, BSYM(2f)
Rabin Vincent28e192d2010-08-03 17:08:09 +0100191 mov pc, r2
Rabin Vincentd3b9dc92010-10-07 17:39:47 +05301922: mcount_exit
193.endm
194
195.macro __ftrace_caller suffix
196 mcount_enter
197
198 mcount_get_lr r1 @ lr of instrumented func
Rabin Vincentd68133b2012-01-24 16:52:52 +0100199 mcount_adjust_addr r0, lr @ instrumented function
Rabin Vincentd3b9dc92010-10-07 17:39:47 +0530200
201 .globl ftrace_call\suffix
202ftrace_call\suffix:
203 bl ftrace_stub
204
Rabin Vincentdd686eb2010-11-06 23:03:21 +0530205#ifdef CONFIG_FUNCTION_GRAPH_TRACER
206 .globl ftrace_graph_call\suffix
207ftrace_graph_call\suffix:
208 mov r0, r0
209#endif
210
Rabin Vincentd3b9dc92010-10-07 17:39:47 +0530211 mcount_exit
212.endm
Uwe Kleine-König181f8172009-08-13 20:38:16 +0200213
Tim Bird376cfa82010-10-09 22:24:38 +0530214.macro __ftrace_graph_caller
215 sub r0, fp, #4 @ &lr of instrumented routine (&parent)
Rabin Vincentdd686eb2010-11-06 23:03:21 +0530216#ifdef CONFIG_DYNAMIC_FTRACE
217 @ called from __ftrace_caller, saved in mcount_enter
218 ldr r1, [sp, #16] @ instrumented routine (func)
Rabin Vincentd68133b2012-01-24 16:52:52 +0100219 mcount_adjust_addr r1, r1
Rabin Vincentdd686eb2010-11-06 23:03:21 +0530220#else
221 @ called from __mcount, untouched in lr
Rabin Vincentd68133b2012-01-24 16:52:52 +0100222 mcount_adjust_addr r1, lr @ instrumented routine (func)
Rabin Vincentdd686eb2010-11-06 23:03:21 +0530223#endif
Tim Bird376cfa82010-10-09 22:24:38 +0530224 mov r2, fp @ frame pointer
225 bl prepare_ftrace_return
226 mcount_exit
227.endm
Abhishek Sagar014c2572008-05-31 14:23:50 +0530228
Rabin Vincent09bfafa2010-08-10 19:32:37 +0100229#ifdef CONFIG_OLD_MCOUNT
230/*
Rabin Vincentd3b9dc92010-10-07 17:39:47 +0530231 * mcount
Rabin Vincent09bfafa2010-08-10 19:32:37 +0100232 */
Abhishek Sagar014c2572008-05-31 14:23:50 +0530233
Rabin Vincentd3b9dc92010-10-07 17:39:47 +0530234.macro mcount_enter
235 stmdb sp!, {r0-r3, lr}
236.endm
237
238.macro mcount_get_lr reg
239 ldr \reg, [fp, #-4]
240.endm
241
242.macro mcount_exit
243 ldr lr, [fp, #-4]
Rabin Vincent28e192d2010-08-03 17:08:09 +0100244 ldmia sp!, {r0-r3, pc}
Rabin Vincentd3b9dc92010-10-07 17:39:47 +0530245.endm
246
247ENTRY(mcount)
248#ifdef CONFIG_DYNAMIC_FTRACE
249 stmdb sp!, {lr}
250 ldr lr, [fp, #-4]
251 ldmia sp!, {pc}
252#else
253 __mcount _old
254#endif
Rabin Vincent72fa62f2010-08-10 19:33:52 +0100255ENDPROC(mcount)
Rabin Vincentd3b9dc92010-10-07 17:39:47 +0530256
257#ifdef CONFIG_DYNAMIC_FTRACE
258ENTRY(ftrace_caller_old)
259 __ftrace_caller _old
260ENDPROC(ftrace_caller_old)
Rabin Vincent09bfafa2010-08-10 19:32:37 +0100261#endif
Abhishek Sagar014c2572008-05-31 14:23:50 +0530262
Tim Bird376cfa82010-10-09 22:24:38 +0530263#ifdef CONFIG_FUNCTION_GRAPH_TRACER
264ENTRY(ftrace_graph_caller_old)
265 __ftrace_graph_caller
266ENDPROC(ftrace_graph_caller_old)
267#endif
268
Rabin Vincentd3b9dc92010-10-07 17:39:47 +0530269.purgem mcount_enter
270.purgem mcount_get_lr
271.purgem mcount_exit
272#endif
273
274/*
275 * __gnu_mcount_nc
276 */
277
278.macro mcount_enter
279 stmdb sp!, {r0-r3, lr}
280.endm
281
282.macro mcount_get_lr reg
283 ldr \reg, [sp, #20]
284.endm
285
286.macro mcount_exit
287 ldmia sp!, {r0-r3, ip, lr}
288 mov pc, ip
289.endm
290
291ENTRY(__gnu_mcount_nc)
292#ifdef CONFIG_DYNAMIC_FTRACE
293 mov ip, lr
294 ldmia sp!, {lr}
295 mov pc, ip
296#else
297 __mcount
298#endif
299ENDPROC(__gnu_mcount_nc)
300
301#ifdef CONFIG_DYNAMIC_FTRACE
302ENTRY(ftrace_caller)
303 __ftrace_caller
304ENDPROC(ftrace_caller)
305#endif
306
Tim Bird376cfa82010-10-09 22:24:38 +0530307#ifdef CONFIG_FUNCTION_GRAPH_TRACER
308ENTRY(ftrace_graph_caller)
309 __ftrace_graph_caller
310ENDPROC(ftrace_graph_caller)
311#endif
312
Rabin Vincentd3b9dc92010-10-07 17:39:47 +0530313.purgem mcount_enter
314.purgem mcount_get_lr
315.purgem mcount_exit
Abhishek Sagar014c2572008-05-31 14:23:50 +0530316
Tim Bird376cfa82010-10-09 22:24:38 +0530317#ifdef CONFIG_FUNCTION_GRAPH_TRACER
318 .globl return_to_handler
319return_to_handler:
320 stmdb sp!, {r0-r3}
321 mov r0, fp @ frame pointer
322 bl ftrace_return_to_handler
323 mov lr, r0 @ r0 has real ret addr
324 ldmia sp!, {r0-r3}
325 mov pc, lr
326#endif
Abhishek Sagar014c2572008-05-31 14:23:50 +0530327
Rabin Vincent72fa62f2010-08-10 19:33:52 +0100328ENTRY(ftrace_stub)
Rabin Vincenta3ba87a2010-08-10 19:37:21 +0100329.Lftrace_stub:
Rabin Vincent28e192d2010-08-03 17:08:09 +0100330 mov pc, lr
Rabin Vincent72fa62f2010-08-10 19:33:52 +0100331ENDPROC(ftrace_stub)
Abhishek Sagar014c2572008-05-31 14:23:50 +0530332
Steven Rostedt606576c2008-10-06 19:06:12 -0400333#endif /* CONFIG_FUNCTION_TRACER */
Abhishek Sagar014c2572008-05-31 14:23:50 +0530334
Linus Torvalds1da177e2005-04-16 15:20:36 -0700335/*=============================================================================
336 * SWI handler
337 *-----------------------------------------------------------------------------
338 */
339
Linus Torvalds1da177e2005-04-16 15:20:36 -0700340 .align 5
341ENTRY(vector_swi)
Russell Kingf4dc9a42005-04-26 15:20:34 +0100342 sub sp, sp, #S_FRAME_SIZE
343 stmia sp, {r0 - r12} @ Calling r0 - r12
Catalin Marinasb86040a2009-07-24 12:32:54 +0100344 ARM( add r8, sp, #S_PC )
345 ARM( stmdb r8, {sp, lr}^ ) @ Calling sp, lr
346 THUMB( mov r8, sp )
347 THUMB( store_user_sp_lr r8, r10, S_SP ) @ calling sp, lr
Russell Kingf4dc9a42005-04-26 15:20:34 +0100348 mrs r8, spsr @ called from non-FIQ mode, so ok.
349 str lr, [sp, #S_PC] @ Save calling PC
350 str r8, [sp, #S_PSR] @ Save CPSR
351 str r0, [sp, #S_OLD_R0] @ Save OLD_R0
Linus Torvalds1da177e2005-04-16 15:20:36 -0700352 zero_fp
Russell Kinge0f9f4a2005-04-26 15:19:24 +0100353
354 /*
355 * Get the system call number.
356 */
Nicolas Pitre3f2829a2006-01-14 16:31:29 +0000357
Nicolas Pitredd35afc2006-01-14 16:36:12 +0000358#if defined(CONFIG_OABI_COMPAT)
Nicolas Pitre3f2829a2006-01-14 16:31:29 +0000359
Nicolas Pitredd35afc2006-01-14 16:36:12 +0000360 /*
361 * If we have CONFIG_OABI_COMPAT then we need to look at the swi
362 * value to determine if it is an EABI or an old ABI call.
363 */
364#ifdef CONFIG_ARM_THUMB
365 tst r8, #PSR_T_BIT
366 movne r10, #0 @ no thumb OABI emulation
367 ldreq r10, [lr, #-4] @ get SWI instruction
368#else
369 ldr r10, [lr, #-4] @ get SWI instruction
Nicolas Pitredd35afc2006-01-14 16:36:12 +0000370#endif
Catalin Marinas26584852009-05-30 14:00:18 +0100371#ifdef CONFIG_CPU_ENDIAN_BE8
372 rev r10, r10 @ little endian instruction
373#endif
Nicolas Pitredd35afc2006-01-14 16:36:12 +0000374
375#elif defined(CONFIG_AEABI)
376
377 /*
378 * Pure EABI user space always put syscall number into scno (r7).
379 */
Nicolas Pitre3f2829a2006-01-14 16:31:29 +0000380#elif defined(CONFIG_ARM_THUMB)
Nicolas Pitredd35afc2006-01-14 16:36:12 +0000381 /* Legacy ABI only, possibly thumb mode. */
Russell Kinge0f9f4a2005-04-26 15:19:24 +0100382 tst r8, #PSR_T_BIT @ this is SPSR from save_user_regs
383 addne scno, r7, #__NR_SYSCALL_BASE @ put OS number in
384 ldreq scno, [lr, #-4]
Nicolas Pitredd35afc2006-01-14 16:36:12 +0000385
Russell Kinge0f9f4a2005-04-26 15:19:24 +0100386#else
Nicolas Pitredd35afc2006-01-14 16:36:12 +0000387 /* Legacy ABI only. */
Russell Kinge0f9f4a2005-04-26 15:19:24 +0100388 ldr scno, [lr, #-4] @ get SWI instruction
389#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700390
391#ifdef CONFIG_ALIGNMENT_TRAP
392 ldr ip, __cr_alignment
393 ldr ip, [ip]
394 mcr p15, 0, ip, c1, c0 @ update control register
395#endif
Russell King1ec42c02005-04-26 15:18:26 +0100396 enable_irq
Linus Torvalds1da177e2005-04-16 15:20:36 -0700397
Linus Torvalds1da177e2005-04-16 15:20:36 -0700398 get_thread_info tsk
Nicolas Pitredd35afc2006-01-14 16:36:12 +0000399 adr tbl, sys_call_table @ load syscall table pointer
Nicolas Pitredd35afc2006-01-14 16:36:12 +0000400
401#if defined(CONFIG_OABI_COMPAT)
402 /*
403 * If the swi argument is zero, this is an EABI call and we do nothing.
404 *
405 * If this is an old ABI call, get the syscall number into scno and
406 * get the old ABI syscall table address.
407 */
408 bics r10, r10, #0xff000000
409 eorne scno, r10, #__NR_OABI_SYSCALL_BASE
410 ldrne tbl, =sys_oabi_call_table
411#elif !defined(CONFIG_AEABI)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700412 bic scno, scno, #0xff000000 @ mask off SWI op-code
Russell Kinge0f9f4a2005-04-26 15:19:24 +0100413 eor scno, scno, #__NR_SYSCALL_BASE @ check OS number
Nicolas Pitre3f2829a2006-01-14 16:31:29 +0000414#endif
Nicolas Pitredd35afc2006-01-14 16:36:12 +0000415
Al Viro81783782012-07-19 17:48:21 +0100416local_restart:
Nicolas Pitre70c70d92010-08-26 15:08:35 -0700417 ldr r10, [tsk, #TI_FLAGS] @ check for syscall tracing
Nicolas Pitre3f2829a2006-01-14 16:31:29 +0000418 stmdb sp!, {r4, r5} @ push fifth and sixth args
Nicolas Pitre70c70d92010-08-26 15:08:35 -0700419
Nathaniel Husted29ef73b2012-01-03 14:23:09 -0500420 tst r10, #_TIF_SYSCALL_WORK @ are we tracing syscalls?
Linus Torvalds1da177e2005-04-16 15:20:36 -0700421 bne __sys_trace
422
Linus Torvalds1da177e2005-04-16 15:20:36 -0700423 cmp scno, #NR_syscalls @ check upper syscall limit
Catalin Marinasb86040a2009-07-24 12:32:54 +0100424 adr lr, BSYM(ret_fast_syscall) @ return address
Linus Torvalds1da177e2005-04-16 15:20:36 -0700425 ldrcc pc, [tbl, scno, lsl #2] @ call sys_* routine
426
427 add r1, sp, #S_OFF
4282: mov why, #0 @ no longer a real syscall
Russell Kinge0f9f4a2005-04-26 15:19:24 +0100429 cmp scno, #(__ARM_NR_BASE - __NR_SYSCALL_BASE)
430 eor r0, scno, #__NR_SYSCALL_BASE @ put OS number back
Linus Torvalds1da177e2005-04-16 15:20:36 -0700431 bcs arm_syscall
432 b sys_ni_syscall @ not private func
Catalin Marinas93ed3972008-08-28 11:22:32 +0100433ENDPROC(vector_swi)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700434
435 /*
436 * This is the really slow path. We're going to be doing
437 * context switches, and waiting for our parent to respond.
438 */
439__sys_trace:
Will Deaconad722542012-07-06 15:50:14 +0100440 mov r1, scno
441 add r0, sp, #S_OFF
442 bl syscall_trace_enter
Linus Torvalds1da177e2005-04-16 15:20:36 -0700443
Catalin Marinasb86040a2009-07-24 12:32:54 +0100444 adr lr, BSYM(__sys_trace_return) @ return address
Nicolas Pitre3f471122006-01-14 19:30:04 +0000445 mov scno, r0 @ syscall number (possibly new)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700446 add r1, sp, #S_R0 + S_OFF @ pointer to regs
447 cmp scno, #NR_syscalls @ check upper syscall limit
Will Deaconc7aa00d2012-07-19 17:49:22 +0100448 ldmccia r1, {r0 - r6} @ have to reload r0 - r6
449 stmccia sp, {r4, r5} @ and update the stack args
Linus Torvalds1da177e2005-04-16 15:20:36 -0700450 ldrcc pc, [tbl, scno, lsl #2] @ call sys_* routine
Kees Cookad75b512012-11-15 22:12:17 +0100451 cmp scno, #-1 @ skip the syscall?
452 bne 2b
453 add sp, sp, #S_OFF @ restore stack
454 b ret_slow_syscall
Linus Torvalds1da177e2005-04-16 15:20:36 -0700455
456__sys_trace_return:
457 str r0, [sp, #S_R0 + S_OFF]! @ save returned r0
Will Deaconad722542012-07-06 15:50:14 +0100458 mov r0, sp
459 bl syscall_trace_exit
Linus Torvalds1da177e2005-04-16 15:20:36 -0700460 b ret_slow_syscall
461
462 .align 5
463#ifdef CONFIG_ALIGNMENT_TRAP
464 .type __cr_alignment, #object
465__cr_alignment:
466 .word cr_alignment
467#endif
Nicolas Pitredd35afc2006-01-14 16:36:12 +0000468 .ltorg
469
470/*
471 * This is the syscall table declaration for native ABI syscalls.
472 * With EABI a couple syscalls are obsolete and defined as sys_ni_syscall.
473 */
474#define ABI(native, compat) native
475#ifdef CONFIG_AEABI
476#define OBSOLETE(syscall) sys_ni_syscall
477#else
478#define OBSOLETE(syscall) syscall
479#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700480
481 .type sys_call_table, #object
482ENTRY(sys_call_table)
483#include "calls.S"
Nicolas Pitredd35afc2006-01-14 16:36:12 +0000484#undef ABI
485#undef OBSOLETE
Linus Torvalds1da177e2005-04-16 15:20:36 -0700486
487/*============================================================================
488 * Special system call wrappers
489 */
490@ r0 = syscall number
Russell King567bd982005-12-17 15:25:42 +0000491@ r8 = syscall table
Linus Torvalds1da177e2005-04-16 15:20:36 -0700492sys_syscall:
Paul Brook52475932006-05-16 14:25:55 +0100493 bic scno, r0, #__NR_OABI_SYSCALL_BASE
Linus Torvalds1da177e2005-04-16 15:20:36 -0700494 cmp scno, #__NR_syscall - __NR_SYSCALL_BASE
495 cmpne scno, #NR_syscalls @ check range
496 stmloia sp, {r5, r6} @ shuffle args
497 movlo r0, r1
498 movlo r1, r2
499 movlo r2, r3
500 movlo r3, r4
501 ldrlo pc, [tbl, scno, lsl #2]
502 b sys_ni_syscall
Catalin Marinas93ed3972008-08-28 11:22:32 +0100503ENDPROC(sys_syscall)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700504
Linus Torvalds1da177e2005-04-16 15:20:36 -0700505sys_sigreturn_wrapper:
506 add r0, sp, #S_OFF
Al Viro653d48b2010-09-17 14:34:39 +0100507 mov why, #0 @ prevent syscall restart handling
Linus Torvalds1da177e2005-04-16 15:20:36 -0700508 b sys_sigreturn
Catalin Marinas93ed3972008-08-28 11:22:32 +0100509ENDPROC(sys_sigreturn_wrapper)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700510
511sys_rt_sigreturn_wrapper:
512 add r0, sp, #S_OFF
Al Viro653d48b2010-09-17 14:34:39 +0100513 mov why, #0 @ prevent syscall restart handling
Linus Torvalds1da177e2005-04-16 15:20:36 -0700514 b sys_rt_sigreturn
Catalin Marinas93ed3972008-08-28 11:22:32 +0100515ENDPROC(sys_rt_sigreturn_wrapper)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700516
517sys_sigaltstack_wrapper:
518 ldr r2, [sp, #S_OFF + S_SP]
519 b do_sigaltstack
Catalin Marinas93ed3972008-08-28 11:22:32 +0100520ENDPROC(sys_sigaltstack_wrapper)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700521
Nicolas Pitre713c4812006-01-14 16:35:03 +0000522sys_statfs64_wrapper:
523 teq r1, #88
524 moveq r1, #84
525 b sys_statfs64
Catalin Marinas93ed3972008-08-28 11:22:32 +0100526ENDPROC(sys_statfs64_wrapper)
Nicolas Pitre713c4812006-01-14 16:35:03 +0000527
528sys_fstatfs64_wrapper:
529 teq r1, #88
530 moveq r1, #84
531 b sys_fstatfs64
Catalin Marinas93ed3972008-08-28 11:22:32 +0100532ENDPROC(sys_fstatfs64_wrapper)
Nicolas Pitre713c4812006-01-14 16:35:03 +0000533
Linus Torvalds1da177e2005-04-16 15:20:36 -0700534/*
535 * Note: off_4k (r5) is always units of 4K. If we can't do the requested
536 * offset, we return EINVAL.
537 */
538sys_mmap2:
539#if PAGE_SHIFT > 12
540 tst r5, #PGOFF_MASK
541 moveq r5, r5, lsr #PAGE_SHIFT - 12
542 streq r5, [sp, #4]
Al Virof8b72562009-11-30 17:37:04 -0500543 beq sys_mmap_pgoff
Linus Torvalds1da177e2005-04-16 15:20:36 -0700544 mov r0, #-EINVAL
Russell King7999d8d2006-06-25 11:17:23 +0100545 mov pc, lr
Linus Torvalds1da177e2005-04-16 15:20:36 -0700546#else
547 str r5, [sp, #4]
Al Virof8b72562009-11-30 17:37:04 -0500548 b sys_mmap_pgoff
Linus Torvalds1da177e2005-04-16 15:20:36 -0700549#endif
Catalin Marinas93ed3972008-08-28 11:22:32 +0100550ENDPROC(sys_mmap2)
Nicolas Pitre687ad012006-01-14 16:35:31 +0000551
552#ifdef CONFIG_OABI_COMPAT
Nicolas Pitredd35afc2006-01-14 16:36:12 +0000553
Nicolas Pitre687ad012006-01-14 16:35:31 +0000554/*
555 * These are syscalls with argument register differences
556 */
557
558sys_oabi_pread64:
559 stmia sp, {r3, r4}
560 b sys_pread64
Catalin Marinas93ed3972008-08-28 11:22:32 +0100561ENDPROC(sys_oabi_pread64)
Nicolas Pitre687ad012006-01-14 16:35:31 +0000562
563sys_oabi_pwrite64:
564 stmia sp, {r3, r4}
565 b sys_pwrite64
Catalin Marinas93ed3972008-08-28 11:22:32 +0100566ENDPROC(sys_oabi_pwrite64)
Nicolas Pitre687ad012006-01-14 16:35:31 +0000567
568sys_oabi_truncate64:
569 mov r3, r2
570 mov r2, r1
571 b sys_truncate64
Catalin Marinas93ed3972008-08-28 11:22:32 +0100572ENDPROC(sys_oabi_truncate64)
Nicolas Pitre687ad012006-01-14 16:35:31 +0000573
574sys_oabi_ftruncate64:
575 mov r3, r2
576 mov r2, r1
577 b sys_ftruncate64
Catalin Marinas93ed3972008-08-28 11:22:32 +0100578ENDPROC(sys_oabi_ftruncate64)
Nicolas Pitre687ad012006-01-14 16:35:31 +0000579
580sys_oabi_readahead:
581 str r3, [sp]
582 mov r3, r2
583 mov r2, r1
584 b sys_readahead
Catalin Marinas93ed3972008-08-28 11:22:32 +0100585ENDPROC(sys_oabi_readahead)
Nicolas Pitre687ad012006-01-14 16:35:31 +0000586
Nicolas Pitredd35afc2006-01-14 16:36:12 +0000587/*
588 * Let's declare a second syscall table for old ABI binaries
589 * using the compatibility syscall entries.
590 */
591#define ABI(native, compat) compat
592#define OBSOLETE(syscall) syscall
593
594 .type sys_oabi_call_table, #object
595ENTRY(sys_oabi_call_table)
596#include "calls.S"
597#undef ABI
598#undef OBSOLETE
599
Nicolas Pitre687ad012006-01-14 16:35:31 +0000600#endif
601