1 /* 2 * Copyright (c) 2007 Apple Inc. All rights reserved. 3 * 4 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@ 5 * 6 * This file contains Original Code and/or Modifications of Original Code 7 * as defined in and that are subject to the Apple Public Source License 8 * Version 2.0 (the 'License'). You may not use this file except in 9 * compliance with the License. The rights granted to you under the License 10 * may not be used to create, or enable the creation or redistribution of, 11 * unlawful or unlicensed copies of an Apple operating system, or to 12 * circumvent, violate, or enable the circumvention or violation of, any 13 * terms of an Apple operating system software license agreement. 14 * 15 * Please obtain a copy of the License at 16 * http://www.opensource.apple.com/apsl/ and read it before using this file. 17 * 18 * The Original Code and all software distributed under the License are 19 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER 20 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, 21 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, 22 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. 23 * Please see the License for the specific language governing rights and 24 * limitations under the License. 25 * 26 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ 27 */ 28 /* 29 * FILE_ID: syscall_sw.h 30 */ 31 32 #ifndef _MACH_ARM_SYSCALL_SW_H_ 33 #define _MACH_ARM_SYSCALL_SW_H_ 34 35 #if defined(__arm__) 36 37 #include <mach/machine/vm_param.h> 38 #include <architecture/arm/asm_help.h> 39 40 /* 0 to 4 args are already loaded in r0-r3 */ 41 #define _kernel_trap_0to4(trap_name, trap_number) \ 42 mov r12, # ## trap_number /* load syscall number */ ; \ 43 swi #SWI_SYSCALL ; \ 44 bx lr /* return */ ; 45 46 #define _kernel_trap_5(trap_name, trap_number) \ 47 mov ip, sp /* save pointer to args */ ; \ 48 stmfd sp!, { r4-r5 } /* save r4-r5, keep stack 64-bit aligned */; \ 49 ldr r4, [ ip ] /* load arg 5 */ ; \ 50 mov r12, # ## trap_number /* load syscall number */ ; \ 51 swi #SWI_SYSCALL ; \ 52 ldmfd sp!, { r4-r5 } /* restore r4-r5 */ ;\ 53 bx lr /* return */ ; 54 55 #define _kernel_trap_6to9(trap_name, trap_number, save_regs, arg_regs) \ 56 mov ip, sp /* save pointer to args */ ; \ 57 stmfd sp!, { save_regs } /* callee saved regs */; \ 58 ldmia ip, { arg_regs } /* load arg registers (above r0-r3) */ ;\ 59 mov r12, # ## trap_number /* load syscall number */ ; \ 60 swi #SWI_SYSCALL ; \ 61 ldmfd sp!, { save_regs } /* restore callee saved regs */ ;\ 62 bx lr /* return */ ; 63 64 #define COMMA , 65 66 /* For the armv7k ABI, the alignment requirements may add padding. So we 67 * let the kernel figure it out and push extra on the stack to avoid un-needed 68 * copy-ins. We are relying on arguments that aren't in registers starting 69 * 32 bytes from sp. */ 70 #if __BIGGEST_ALIGNMENT__ > 4 71 72 #define _kernel_trap_0(trap_name, trap_number) _kernel_trap_0to4(trap_name, trap_number) 73 #define _kernel_trap_1(trap_name, trap_number) _kernel_trap_0to4(trap_name, trap_number) 74 #define _kernel_trap_2(trap_name, trap_number) _kernel_trap_0to4(trap_name, trap_number) 75 #define _kernel_trap_3(trap_name, trap_number) _kernel_trap_0to4(trap_name, trap_number) 76 #define _kernel_trap_4(trap_name, trap_number) _kernel_trap_6to9(trap_name, trap_number, r4-r5, r4-r5) 77 #undef _kernel_trap_5 78 #define _kernel_trap_5(trap_name, trap_number) _kernel_trap_6to9(trap_name, trap_number, r4-r5, r4-r5) 79 #define _kernel_trap_6(trap_name, trap_number) _kernel_trap_6to9(trap_name, trap_number, r4-r6 COMMA r8, r4-r6 COMMA r8) 80 #define _kernel_trap_7(trap_name, trap_number) _kernel_trap_6to9(trap_name, trap_number, r4-r6 COMMA r8, r4-r6 COMMA r8) 81 #define _kernel_trap_8(trap_name, trap_number) _kernel_trap_6to9(trap_name, trap_number, r4-r6 COMMA r8, r4-r6 COMMA r8) 82 #define _kernel_trap_9(trap_name, trap_number) _kernel_trap_6to9(trap_name, trap_number, r4-r6 COMMA r8, r4-r6 COMMA r8) 83 #else // !(__BIGGEST_ALIGNMENT__ > 4) 84 85 #define _kernel_trap_0(trap_name, trap_number) _kernel_trap_0to4(trap_name, trap_number) 86 #define _kernel_trap_1(trap_name, trap_number) _kernel_trap_0to4(trap_name, trap_number) 87 #define _kernel_trap_2(trap_name, trap_number) _kernel_trap_0to4(trap_name, trap_number) 88 #define _kernel_trap_3(trap_name, trap_number) _kernel_trap_0to4(trap_name, trap_number) 89 #define _kernel_trap_4(trap_name, trap_number) _kernel_trap_0to4(trap_name, trap_number) 90 /* _kernel_trap_5 defined above */ 91 #define _kernel_trap_6(trap_name, trap_number) _kernel_trap_6to9(trap_name, trap_number, r4-r5, r4-r5) 92 /* need to save r8 not just for alignment but because mach_msg_trap overwrites the eighth argument */ 93 #define _kernel_trap_7(trap_name, trap_number) _kernel_trap_6to9(trap_name, trap_number, r4-r6 COMMA r8, r4-r6) 94 #define _kernel_trap_8(trap_name, trap_number) _kernel_trap_6to9(trap_name, trap_number, r4-r6 COMMA r8, r4-r6 COMMA r8) 95 /* there is only one nine-argument trap (mach_msg_overwrite_trap) and it doesn't use the ninth argument */ 96 #define _kernel_trap_9(trap_name, trap_number) _kernel_trap_8(trap_name, trap_number) 97 98 #endif // __BIGGEST_ALIGNMENT__ > 4 99 100 101 /* select the appropriate trap macro based off the number of args */ 102 #define kernel_trap(trap_name, trap_number, num_args) \ 103 LEAF(_##trap_name, 0) \ 104 _kernel_trap_##num_args(trap_name, trap_number) 105 106 #elif defined(__arm64__) 107 108 #include <mach/machine/vm_param.h> 109 110 #define kernel_trap(trap_name, trap_number, num_args) \ 111 .globl _##trap_name %% \ 112 .text %% \ 113 .align 2 %% \ 114 _##trap_name: %% \ 115 mov x16, #(trap_number) %% \ 116 svc #SWI_SYSCALL %% \ 117 ret 118 119 #else 120 #error Unsupported architecture 121 #endif 122 123 #endif /* _MACH_ARM_SYSCALL_SW_H_ */ 124