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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
11#include <asm/assembler.h>
12#include <asm/unistd.h>
13#include <asm/ftrace.h>
14#include <asm/unwind.h>
15
16#ifdef CONFIG_NEED_RET_TO_USER
17#include <mach/entry-macro.S>
18#else
19 .macro arch_ret_to_user, tmp1, tmp2
20 .endm
21#endif
22
23#include "entry-header.S"
24
25
26 .align 5
27#if !(IS_ENABLED(CONFIG_TRACE_IRQFLAGS) || IS_ENABLED(CONFIG_CONTEXT_TRACKING))
28/*
29 * This is the fast syscall return path. We do as little as possible here,
30 * such as avoiding writing r0 to the stack. We only use this path if we
31 * have tracing and context tracking disabled - the overheads from those
32 * features make this path too inefficient.
33 */
34ret_fast_syscall:
35 UNWIND(.fnstart )
36 UNWIND(.cantunwind )
37 disable_irq_notrace @ disable interrupts
38 ldr r1, [tsk, #TI_FLAGS] @ re-check for syscall tracing
39 tst r1, #_TIF_SYSCALL_WORK | _TIF_WORK_MASK
40 bne fast_work_pending
41
42 /* perform architecture specific actions before user return */
43 arch_ret_to_user r1, lr
44
45 restore_user_regs fast = 1, offset = S_OFF
46 UNWIND(.fnend )
47ENDPROC(ret_fast_syscall)
48
49 /* Ok, we need to do extra processing, enter the slow path. */
50fast_work_pending:
51 str r0, [sp, #S_R0+S_OFF]! @ returned r0
52 /* fall through to work_pending */
53#else
54/*
55 * The "replacement" ret_fast_syscall for when tracing or context tracking
56 * is enabled. As we will need to call out to some C functions, we save
57 * r0 first to avoid needing to save registers around each C function call.
58 */
59ret_fast_syscall:
60 UNWIND(.fnstart )
61 UNWIND(.cantunwind )
62 str r0, [sp, #S_R0 + S_OFF]! @ save returned r0
63 disable_irq_notrace @ disable interrupts
64 ldr r1, [tsk, #TI_FLAGS] @ re-check for syscall tracing
65 tst r1, #_TIF_SYSCALL_WORK | _TIF_WORK_MASK
66 beq no_work_pending
67 UNWIND(.fnend )
68ENDPROC(ret_fast_syscall)
69
70 /* Slower path - fall through to work_pending */
71#endif
72
73 tst r1, #_TIF_SYSCALL_WORK
74 bne __sys_trace_return_nosave
75slow_work_pending:
76 mov r0, sp @ 'regs'
77 mov r2, why @ 'syscall'
78 bl do_work_pending
79 cmp r0, #0
80 beq no_work_pending
81 movlt scno, #(__NR_restart_syscall - __NR_SYSCALL_BASE)
82 ldmia sp, {r0 - r6} @ have to reload r0 - r6
83 b local_restart @ ... and off we go
84ENDPROC(ret_fast_syscall)
85
86/*
87 * "slow" syscall return path. "why" tells us if this was a real syscall.
88 * IRQs may be enabled here, so always disable them. Note that we use the
89 * "notrace" version to avoid calling into the tracing code unnecessarily.
90 * do_work_pending() will update this state if necessary.
91 */
92ENTRY(ret_to_user)
93ret_slow_syscall:
94 disable_irq_notrace @ disable interrupts
95ENTRY(ret_to_user_from_irq)
96 ldr r1, [tsk, #TI_FLAGS]
97 tst r1, #_TIF_WORK_MASK
98 bne slow_work_pending
99no_work_pending:
100 asm_trace_hardirqs_on save = 0
101
102 /* perform architecture specific actions before user return */
103 arch_ret_to_user r1, lr
104 ct_user_enter save = 0
105
106 restore_user_regs fast = 0, offset = 0
107ENDPROC(ret_to_user_from_irq)
108ENDPROC(ret_to_user)
109
110/*
111 * This is how we return from a fork.
112 */
113ENTRY(ret_from_fork)
114 bl schedule_tail
115 cmp r5, #0
116 movne r0, r4
117 badrne lr, 1f
118 retne r5
1191: get_thread_info tsk
120 b ret_slow_syscall
121ENDPROC(ret_from_fork)
122
123 .equ NR_syscalls,0
124#define CALL(x) .equ NR_syscalls,NR_syscalls+1
125#include "calls.S"
126
127/*
128 * Ensure that the system call table is equal to __NR_syscalls,
129 * which is the value the rest of the system sees
130 */
131.ifne NR_syscalls - __NR_syscalls
132.error "__NR_syscalls is not equal to the size of the syscall table"
133.endif
134
135#undef CALL
136#define CALL(x) .long x
137
138/*=============================================================================
139 * SWI handler
140 *-----------------------------------------------------------------------------
141 */
142
143 .align 5
144ENTRY(vector_swi)
145#ifdef CONFIG_CPU_V7M
146 v7m_exception_entry
147#else
148 sub sp, sp, #S_FRAME_SIZE
149 stmia sp, {r0 - r12} @ Calling r0 - r12
150 ARM( add r8, sp, #S_PC )
151 ARM( stmdb r8, {sp, lr}^ ) @ Calling sp, lr
152 THUMB( mov r8, sp )
153 THUMB( store_user_sp_lr r8, r10, S_SP ) @ calling sp, lr
154 mrs r8, spsr @ called from non-FIQ mode, so ok.
155 str lr, [sp, #S_PC] @ Save calling PC
156 str r8, [sp, #S_PSR] @ Save CPSR
157 str r0, [sp, #S_OLD_R0] @ Save OLD_R0
158#endif
159 zero_fp
160 alignment_trap r10, ip, __cr_alignment
161 enable_irq
162 ct_user_exit
163 get_thread_info tsk
164
165 /*
166 * Get the system call number.
167 */
168
169#if defined(CONFIG_OABI_COMPAT)
170
171 /*
172 * If we have CONFIG_OABI_COMPAT then we need to look at the swi
173 * value to determine if it is an EABI or an old ABI call.
174 */
175#ifdef CONFIG_ARM_THUMB
176 tst r8, #PSR_T_BIT
177 movne r10, #0 @ no thumb OABI emulation
178 USER( ldreq r10, [lr, #-4] ) @ get SWI instruction
179#else
180 USER( ldr r10, [lr, #-4] ) @ get SWI instruction
181#endif
182 ARM_BE8(rev r10, r10) @ little endian instruction
183
184#elif defined(CONFIG_AEABI)
185
186 /*
187 * Pure EABI user space always put syscall number into scno (r7).
188 */
189#elif defined(CONFIG_ARM_THUMB)
190 /* Legacy ABI only, possibly thumb mode. */
191 tst r8, #PSR_T_BIT @ this is SPSR from save_user_regs
192 addne scno, r7, #__NR_SYSCALL_BASE @ put OS number in
193 USER( ldreq scno, [lr, #-4] )
194
195#else
196 /* Legacy ABI only. */
197 USER( ldr scno, [lr, #-4] ) @ get SWI instruction
198#endif
199
200 uaccess_disable tbl
201
202 adr tbl, sys_call_table @ load syscall table pointer
203
204#if defined(CONFIG_OABI_COMPAT)
205 /*
206 * If the swi argument is zero, this is an EABI call and we do nothing.
207 *
208 * If this is an old ABI call, get the syscall number into scno and
209 * get the old ABI syscall table address.
210 */
211 bics r10, r10, #0xff000000
212 eorne scno, r10, #__NR_OABI_SYSCALL_BASE
213 ldrne tbl, =sys_oabi_call_table
214#elif !defined(CONFIG_AEABI)
215 bic scno, scno, #0xff000000 @ mask off SWI op-code
216 eor scno, scno, #__NR_SYSCALL_BASE @ check OS number
217#endif
218
219local_restart:
220 ldr r10, [tsk, #TI_FLAGS] @ check for syscall tracing
221 stmdb sp!, {r4, r5} @ push fifth and sixth args
222
223 tst r10, #_TIF_SYSCALL_WORK @ are we tracing syscalls?
224 bne __sys_trace
225
226 cmp scno, #NR_syscalls @ check upper syscall limit
227 badr lr, ret_fast_syscall @ return address
228 ldrcc pc, [tbl, scno, lsl #2] @ call sys_* routine
229
230 add r1, sp, #S_OFF
2312: cmp scno, #(__ARM_NR_BASE - __NR_SYSCALL_BASE)
232 eor r0, scno, #__NR_SYSCALL_BASE @ put OS number back
233 bcs arm_syscall
234 mov why, #0 @ no longer a real syscall
235 b sys_ni_syscall @ not private func
236
237#if defined(CONFIG_OABI_COMPAT) || !defined(CONFIG_AEABI)
238 /*
239 * We failed to handle a fault trying to access the page
240 * containing the swi instruction, but we're not really in a
241 * position to return -EFAULT. Instead, return back to the
242 * instruction and re-enter the user fault handling path trying
243 * to page it in. This will likely result in sending SEGV to the
244 * current task.
245 */
2469001:
247 sub lr, lr, #4
248 str lr, [sp, #S_PC]
249 b ret_fast_syscall
250#endif
251ENDPROC(vector_swi)
252
253 /*
254 * This is the really slow path. We're going to be doing
255 * context switches, and waiting for our parent to respond.
256 */
257__sys_trace:
258 mov r1, scno
259 add r0, sp, #S_OFF
260 bl syscall_trace_enter
261
262 badr lr, __sys_trace_return @ return address
263 mov scno, r0 @ syscall number (possibly new)
264 add r1, sp, #S_R0 + S_OFF @ pointer to regs
265 cmp scno, #NR_syscalls @ check upper syscall limit
266 ldmccia r1, {r0 - r6} @ have to reload r0 - r6
267 stmccia sp, {r4, r5} @ and update the stack args
268 ldrcc pc, [tbl, scno, lsl #2] @ call sys_* routine
269 cmp scno, #-1 @ skip the syscall?
270 bne 2b
271 add sp, sp, #S_OFF @ restore stack
272 b ret_slow_syscall
273
274__sys_trace_return:
275 str r0, [sp, #S_R0 + S_OFF]! @ save returned r0
276 mov r0, sp
277 bl syscall_trace_exit
278 b ret_slow_syscall
279
280__sys_trace_return_nosave:
281 enable_irq_notrace
282 mov r0, sp
283 bl syscall_trace_exit
284 b ret_slow_syscall
285
286 .align 5
287#ifdef CONFIG_ALIGNMENT_TRAP
288 .type __cr_alignment, #object
289__cr_alignment:
290 .word cr_alignment
291#endif
292 .ltorg
293
294/*
295 * This is the syscall table declaration for native ABI syscalls.
296 * With EABI a couple syscalls are obsolete and defined as sys_ni_syscall.
297 */
298#define ABI(native, compat) native
299#ifdef CONFIG_AEABI
300#define OBSOLETE(syscall) sys_ni_syscall
301#else
302#define OBSOLETE(syscall) syscall
303#endif
304
305 .type sys_call_table, #object
306ENTRY(sys_call_table)
307#include "calls.S"
308#undef ABI
309#undef OBSOLETE
310
311/*============================================================================
312 * Special system call wrappers
313 */
314@ r0 = syscall number
315@ r8 = syscall table
316sys_syscall:
317 bic scno, r0, #__NR_OABI_SYSCALL_BASE
318 cmp scno, #__NR_syscall - __NR_SYSCALL_BASE
319 cmpne scno, #NR_syscalls @ check range
320 stmloia sp, {r5, r6} @ shuffle args
321 movlo r0, r1
322 movlo r1, r2
323 movlo r2, r3
324 movlo r3, r4
325 ldrlo pc, [tbl, scno, lsl #2]
326 b sys_ni_syscall
327ENDPROC(sys_syscall)
328
329sys_sigreturn_wrapper:
330 add r0, sp, #S_OFF
331 mov why, #0 @ prevent syscall restart handling
332 b sys_sigreturn
333ENDPROC(sys_sigreturn_wrapper)
334
335sys_rt_sigreturn_wrapper:
336 add r0, sp, #S_OFF
337 mov why, #0 @ prevent syscall restart handling
338 b sys_rt_sigreturn
339ENDPROC(sys_rt_sigreturn_wrapper)
340
341sys_statfs64_wrapper:
342 teq r1, #88
343 moveq r1, #84
344 b sys_statfs64
345ENDPROC(sys_statfs64_wrapper)
346
347sys_fstatfs64_wrapper:
348 teq r1, #88
349 moveq r1, #84
350 b sys_fstatfs64
351ENDPROC(sys_fstatfs64_wrapper)
352
353/*
354 * Note: off_4k (r5) is always units of 4K. If we can't do the requested
355 * offset, we return EINVAL.
356 */
357sys_mmap2:
358#if PAGE_SHIFT > 12
359 tst r5, #PGOFF_MASK
360 moveq r5, r5, lsr #PAGE_SHIFT - 12
361 streq r5, [sp, #4]
362 beq sys_mmap_pgoff
363 mov r0, #-EINVAL
364 ret lr
365#else
366 str r5, [sp, #4]
367 b sys_mmap_pgoff
368#endif
369ENDPROC(sys_mmap2)
370
371#ifdef CONFIG_OABI_COMPAT
372
373/*
374 * These are syscalls with argument register differences
375 */
376
377sys_oabi_pread64:
378 stmia sp, {r3, r4}
379 b sys_pread64
380ENDPROC(sys_oabi_pread64)
381
382sys_oabi_pwrite64:
383 stmia sp, {r3, r4}
384 b sys_pwrite64
385ENDPROC(sys_oabi_pwrite64)
386
387sys_oabi_truncate64:
388 mov r3, r2
389 mov r2, r1
390 b sys_truncate64
391ENDPROC(sys_oabi_truncate64)
392
393sys_oabi_ftruncate64:
394 mov r3, r2
395 mov r2, r1
396 b sys_ftruncate64
397ENDPROC(sys_oabi_ftruncate64)
398
399sys_oabi_readahead:
400 str r3, [sp]
401 mov r3, r2
402 mov r2, r1
403 b sys_readahead
404ENDPROC(sys_oabi_readahead)
405
406/*
407 * Let's declare a second syscall table for old ABI binaries
408 * using the compatibility syscall entries.
409 */
410#define ABI(native, compat) compat
411#define OBSOLETE(syscall) syscall
412
413 .type sys_oabi_call_table, #object
414ENTRY(sys_oabi_call_table)
415#include "calls.S"
416#undef ABI
417#undef OBSOLETE
418
419#endif
420
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
11#include <asm/assembler.h>
12#include <asm/unistd.h>
13#include <asm/ftrace.h>
14#include <asm/unwind.h>
15#ifdef CONFIG_AEABI
16#include <asm/unistd-oabi.h>
17#endif
18
19 .equ NR_syscalls, __NR_syscalls
20
21#ifdef CONFIG_NEED_RET_TO_USER
22#include <mach/entry-macro.S>
23#else
24 .macro arch_ret_to_user, tmp1, tmp2
25 .endm
26#endif
27
28#include "entry-header.S"
29
30
31 .align 5
32#if !(IS_ENABLED(CONFIG_TRACE_IRQFLAGS) || IS_ENABLED(CONFIG_CONTEXT_TRACKING))
33/*
34 * This is the fast syscall return path. We do as little as possible here,
35 * such as avoiding writing r0 to the stack. We only use this path if we
36 * have tracing and context tracking disabled - the overheads from those
37 * features make this path too inefficient.
38 */
39ret_fast_syscall:
40 UNWIND(.fnstart )
41 UNWIND(.cantunwind )
42 disable_irq_notrace @ disable interrupts
43 ldr r1, [tsk, #TI_FLAGS] @ re-check for syscall tracing
44 tst r1, #_TIF_SYSCALL_WORK | _TIF_WORK_MASK
45 bne fast_work_pending
46
47 /* perform architecture specific actions before user return */
48 arch_ret_to_user r1, lr
49
50 restore_user_regs fast = 1, offset = S_OFF
51 UNWIND(.fnend )
52ENDPROC(ret_fast_syscall)
53
54 /* Ok, we need to do extra processing, enter the slow path. */
55fast_work_pending:
56 str r0, [sp, #S_R0+S_OFF]! @ returned r0
57 /* fall through to work_pending */
58#else
59/*
60 * The "replacement" ret_fast_syscall for when tracing or context tracking
61 * is enabled. As we will need to call out to some C functions, we save
62 * r0 first to avoid needing to save registers around each C function call.
63 */
64ret_fast_syscall:
65 UNWIND(.fnstart )
66 UNWIND(.cantunwind )
67 str r0, [sp, #S_R0 + S_OFF]! @ save returned r0
68 disable_irq_notrace @ disable interrupts
69 ldr r1, [tsk, #TI_FLAGS] @ re-check for syscall tracing
70 tst r1, #_TIF_SYSCALL_WORK | _TIF_WORK_MASK
71 beq no_work_pending
72 UNWIND(.fnend )
73ENDPROC(ret_fast_syscall)
74
75 /* Slower path - fall through to work_pending */
76#endif
77
78 tst r1, #_TIF_SYSCALL_WORK
79 bne __sys_trace_return_nosave
80slow_work_pending:
81 mov r0, sp @ 'regs'
82 mov r2, why @ 'syscall'
83 bl do_work_pending
84 cmp r0, #0
85 beq no_work_pending
86 movlt scno, #(__NR_restart_syscall - __NR_SYSCALL_BASE)
87 ldmia sp, {r0 - r6} @ have to reload r0 - r6
88 b local_restart @ ... and off we go
89ENDPROC(ret_fast_syscall)
90
91/*
92 * "slow" syscall return path. "why" tells us if this was a real syscall.
93 * IRQs may be enabled here, so always disable them. Note that we use the
94 * "notrace" version to avoid calling into the tracing code unnecessarily.
95 * do_work_pending() will update this state if necessary.
96 */
97ENTRY(ret_to_user)
98ret_slow_syscall:
99 disable_irq_notrace @ disable interrupts
100ENTRY(ret_to_user_from_irq)
101 ldr r1, [tsk, #TI_FLAGS]
102 tst r1, #_TIF_WORK_MASK
103 bne slow_work_pending
104no_work_pending:
105 asm_trace_hardirqs_on save = 0
106
107 /* perform architecture specific actions before user return */
108 arch_ret_to_user r1, lr
109 ct_user_enter save = 0
110
111 restore_user_regs fast = 0, offset = 0
112ENDPROC(ret_to_user_from_irq)
113ENDPROC(ret_to_user)
114
115/*
116 * This is how we return from a fork.
117 */
118ENTRY(ret_from_fork)
119 bl schedule_tail
120 cmp r5, #0
121 movne r0, r4
122 badrne lr, 1f
123 retne r5
1241: get_thread_info tsk
125 b ret_slow_syscall
126ENDPROC(ret_from_fork)
127
128/*=============================================================================
129 * SWI handler
130 *-----------------------------------------------------------------------------
131 */
132
133 .align 5
134ENTRY(vector_swi)
135#ifdef CONFIG_CPU_V7M
136 v7m_exception_entry
137#else
138 sub sp, sp, #PT_REGS_SIZE
139 stmia sp, {r0 - r12} @ Calling r0 - r12
140 ARM( add r8, sp, #S_PC )
141 ARM( stmdb r8, {sp, lr}^ ) @ Calling sp, lr
142 THUMB( mov r8, sp )
143 THUMB( store_user_sp_lr r8, r10, S_SP ) @ calling sp, lr
144 mrs r8, spsr @ called from non-FIQ mode, so ok.
145 str lr, [sp, #S_PC] @ Save calling PC
146 str r8, [sp, #S_PSR] @ Save CPSR
147 str r0, [sp, #S_OLD_R0] @ Save OLD_R0
148#endif
149 zero_fp
150 alignment_trap r10, ip, __cr_alignment
151 enable_irq
152 ct_user_exit
153 get_thread_info tsk
154
155 /*
156 * Get the system call number.
157 */
158
159#if defined(CONFIG_OABI_COMPAT)
160
161 /*
162 * If we have CONFIG_OABI_COMPAT then we need to look at the swi
163 * value to determine if it is an EABI or an old ABI call.
164 */
165#ifdef CONFIG_ARM_THUMB
166 tst r8, #PSR_T_BIT
167 movne r10, #0 @ no thumb OABI emulation
168 USER( ldreq r10, [lr, #-4] ) @ get SWI instruction
169#else
170 USER( ldr r10, [lr, #-4] ) @ get SWI instruction
171#endif
172 ARM_BE8(rev r10, r10) @ little endian instruction
173
174#elif defined(CONFIG_AEABI)
175
176 /*
177 * Pure EABI user space always put syscall number into scno (r7).
178 */
179#elif defined(CONFIG_ARM_THUMB)
180 /* Legacy ABI only, possibly thumb mode. */
181 tst r8, #PSR_T_BIT @ this is SPSR from save_user_regs
182 addne scno, r7, #__NR_SYSCALL_BASE @ put OS number in
183 USER( ldreq scno, [lr, #-4] )
184
185#else
186 /* Legacy ABI only. */
187 USER( ldr scno, [lr, #-4] ) @ get SWI instruction
188#endif
189
190 uaccess_disable tbl
191
192 adr tbl, sys_call_table @ load syscall table pointer
193
194#if defined(CONFIG_OABI_COMPAT)
195 /*
196 * If the swi argument is zero, this is an EABI call and we do nothing.
197 *
198 * If this is an old ABI call, get the syscall number into scno and
199 * get the old ABI syscall table address.
200 */
201 bics r10, r10, #0xff000000
202 eorne scno, r10, #__NR_OABI_SYSCALL_BASE
203 ldrne tbl, =sys_oabi_call_table
204#elif !defined(CONFIG_AEABI)
205 bic scno, scno, #0xff000000 @ mask off SWI op-code
206 eor scno, scno, #__NR_SYSCALL_BASE @ check OS number
207#endif
208
209local_restart:
210 ldr r10, [tsk, #TI_FLAGS] @ check for syscall tracing
211 stmdb sp!, {r4, r5} @ push fifth and sixth args
212
213 tst r10, #_TIF_SYSCALL_WORK @ are we tracing syscalls?
214 bne __sys_trace
215
216 cmp scno, #NR_syscalls @ check upper syscall limit
217 badr lr, ret_fast_syscall @ return address
218 ldrcc pc, [tbl, scno, lsl #2] @ call sys_* routine
219
220 add r1, sp, #S_OFF
2212: cmp scno, #(__ARM_NR_BASE - __NR_SYSCALL_BASE)
222 eor r0, scno, #__NR_SYSCALL_BASE @ put OS number back
223 bcs arm_syscall
224 mov why, #0 @ no longer a real syscall
225 b sys_ni_syscall @ not private func
226
227#if defined(CONFIG_OABI_COMPAT) || !defined(CONFIG_AEABI)
228 /*
229 * We failed to handle a fault trying to access the page
230 * containing the swi instruction, but we're not really in a
231 * position to return -EFAULT. Instead, return back to the
232 * instruction and re-enter the user fault handling path trying
233 * to page it in. This will likely result in sending SEGV to the
234 * current task.
235 */
2369001:
237 sub lr, lr, #4
238 str lr, [sp, #S_PC]
239 b ret_fast_syscall
240#endif
241ENDPROC(vector_swi)
242
243 /*
244 * This is the really slow path. We're going to be doing
245 * context switches, and waiting for our parent to respond.
246 */
247__sys_trace:
248 mov r1, scno
249 add r0, sp, #S_OFF
250 bl syscall_trace_enter
251
252 badr lr, __sys_trace_return @ return address
253 mov scno, r0 @ syscall number (possibly new)
254 add r1, sp, #S_R0 + S_OFF @ pointer to regs
255 cmp scno, #NR_syscalls @ check upper syscall limit
256 ldmccia r1, {r0 - r6} @ have to reload r0 - r6
257 stmccia sp, {r4, r5} @ and update the stack args
258 ldrcc pc, [tbl, scno, lsl #2] @ call sys_* routine
259 cmp scno, #-1 @ skip the syscall?
260 bne 2b
261 add sp, sp, #S_OFF @ restore stack
262 b ret_slow_syscall
263
264__sys_trace_return:
265 str r0, [sp, #S_R0 + S_OFF]! @ save returned r0
266 mov r0, sp
267 bl syscall_trace_exit
268 b ret_slow_syscall
269
270__sys_trace_return_nosave:
271 enable_irq_notrace
272 mov r0, sp
273 bl syscall_trace_exit
274 b ret_slow_syscall
275
276 .align 5
277#ifdef CONFIG_ALIGNMENT_TRAP
278 .type __cr_alignment, #object
279__cr_alignment:
280 .word cr_alignment
281#endif
282 .ltorg
283
284 .macro syscall_table_start, sym
285 .equ __sys_nr, 0
286 .type \sym, #object
287ENTRY(\sym)
288 .endm
289
290 .macro syscall, nr, func
291 .ifgt __sys_nr - \nr
292 .error "Duplicated/unorded system call entry"
293 .endif
294 .rept \nr - __sys_nr
295 .long sys_ni_syscall
296 .endr
297 .long \func
298 .equ __sys_nr, \nr + 1
299 .endm
300
301 .macro syscall_table_end, sym
302 .ifgt __sys_nr - __NR_syscalls
303 .error "System call table too big"
304 .endif
305 .rept __NR_syscalls - __sys_nr
306 .long sys_ni_syscall
307 .endr
308 .size \sym, . - \sym
309 .endm
310
311#define NATIVE(nr, func) syscall nr, func
312
313/*
314 * This is the syscall table declaration for native ABI syscalls.
315 * With EABI a couple syscalls are obsolete and defined as sys_ni_syscall.
316 */
317 syscall_table_start sys_call_table
318#define COMPAT(nr, native, compat) syscall nr, native
319#ifdef CONFIG_AEABI
320#include <calls-eabi.S>
321#else
322#include <calls-oabi.S>
323#endif
324#undef COMPAT
325 syscall_table_end sys_call_table
326
327/*============================================================================
328 * Special system call wrappers
329 */
330@ r0 = syscall number
331@ r8 = syscall table
332sys_syscall:
333 bic scno, r0, #__NR_OABI_SYSCALL_BASE
334 cmp scno, #__NR_syscall - __NR_SYSCALL_BASE
335 cmpne scno, #NR_syscalls @ check range
336 stmloia sp, {r5, r6} @ shuffle args
337 movlo r0, r1
338 movlo r1, r2
339 movlo r2, r3
340 movlo r3, r4
341 ldrlo pc, [tbl, scno, lsl #2]
342 b sys_ni_syscall
343ENDPROC(sys_syscall)
344
345sys_sigreturn_wrapper:
346 add r0, sp, #S_OFF
347 mov why, #0 @ prevent syscall restart handling
348 b sys_sigreturn
349ENDPROC(sys_sigreturn_wrapper)
350
351sys_rt_sigreturn_wrapper:
352 add r0, sp, #S_OFF
353 mov why, #0 @ prevent syscall restart handling
354 b sys_rt_sigreturn
355ENDPROC(sys_rt_sigreturn_wrapper)
356
357sys_statfs64_wrapper:
358 teq r1, #88
359 moveq r1, #84
360 b sys_statfs64
361ENDPROC(sys_statfs64_wrapper)
362
363sys_fstatfs64_wrapper:
364 teq r1, #88
365 moveq r1, #84
366 b sys_fstatfs64
367ENDPROC(sys_fstatfs64_wrapper)
368
369/*
370 * Note: off_4k (r5) is always units of 4K. If we can't do the requested
371 * offset, we return EINVAL.
372 */
373sys_mmap2:
374#if PAGE_SHIFT > 12
375 tst r5, #PGOFF_MASK
376 moveq r5, r5, lsr #PAGE_SHIFT - 12
377 streq r5, [sp, #4]
378 beq sys_mmap_pgoff
379 mov r0, #-EINVAL
380 ret lr
381#else
382 str r5, [sp, #4]
383 b sys_mmap_pgoff
384#endif
385ENDPROC(sys_mmap2)
386
387#ifdef CONFIG_OABI_COMPAT
388
389/*
390 * These are syscalls with argument register differences
391 */
392
393sys_oabi_pread64:
394 stmia sp, {r3, r4}
395 b sys_pread64
396ENDPROC(sys_oabi_pread64)
397
398sys_oabi_pwrite64:
399 stmia sp, {r3, r4}
400 b sys_pwrite64
401ENDPROC(sys_oabi_pwrite64)
402
403sys_oabi_truncate64:
404 mov r3, r2
405 mov r2, r1
406 b sys_truncate64
407ENDPROC(sys_oabi_truncate64)
408
409sys_oabi_ftruncate64:
410 mov r3, r2
411 mov r2, r1
412 b sys_ftruncate64
413ENDPROC(sys_oabi_ftruncate64)
414
415sys_oabi_readahead:
416 str r3, [sp]
417 mov r3, r2
418 mov r2, r1
419 b sys_readahead
420ENDPROC(sys_oabi_readahead)
421
422/*
423 * Let's declare a second syscall table for old ABI binaries
424 * using the compatibility syscall entries.
425 */
426 syscall_table_start sys_oabi_call_table
427#define COMPAT(nr, native, compat) syscall nr, compat
428#include <calls-oabi.S>
429 syscall_table_end sys_oabi_call_table
430
431#endif
432