| 1 | #ifndef _SYSCALLASM_H_ |
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| 2 | #define _SYSCALLASM_H_ |
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| 3 | |
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| 4 | /* |
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| 5 | * This file defines the system calls for SPARC for the assembler. |
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| 6 | * Anything C-ish is not allowed in this file. |
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| 7 | * C files should include syscall.h. |
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| 8 | */ |
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| 9 | |
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| 10 | #include "syscall.h" |
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| 11 | |
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| 12 | /* Some macros for writing assember syscall stubs. */ |
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| 13 | |
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| 14 | #ifdef SVR4 |
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| 15 | #define TEXT_SECTION .section ".text" |
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| 16 | #define DATA_SECTION .section ".data" |
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| 17 | #define ALIGN(x) .align x |
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| 18 | #define GLOBAL(sym) .global sym |
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| 19 | #define WORD(x) .long x |
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| 20 | #define ASM_SYMBOL(name) name |
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| 21 | #define ASM_PRIVATE_SYMBOL(name) _##name |
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| 22 | #define SYSCALL_TRAP 8 |
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| 23 | #else |
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| 24 | #define TEXT_SECTION .text |
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| 25 | #define DATA_SECTION .data |
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| 26 | #define ALIGN(x) .align x |
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| 27 | #define GLOBAL(sym) .global sym |
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| 28 | #define WORD(x) .word x |
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| 29 | #define ASM_SYMBOL(name) _##name |
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| 30 | #define ASM_PRIVATE_SYMBOL(name) name |
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| 31 | #define SYSCALL_TRAP 0 |
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| 32 | #endif |
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| 33 | |
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| 34 | #define defsyscall(name, n) \ |
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| 35 | TEXT_SECTION ; \ |
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| 36 | ALIGN (4) ; \ |
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| 37 | GLOBAL (ASM_SYMBOL (name)) ; \ |
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| 38 | ASM_SYMBOL (name): \ |
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| 39 | mov n,%g1 ; \ |
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| 40 | ta SYSCALL_TRAP ; \ |
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| 41 | bcc noerr ; \ |
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| 42 | sethi %hi (ASM_PRIVATE_SYMBOL (cerror)),%g1 ; \ |
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| 43 | or %g1,%lo (ASM_PRIVATE_SYMBOL (cerror)),%g1 ; \ |
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| 44 | jmpl %g1+%g0,%g0 ; \ |
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| 45 | nop ; \ |
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| 46 | noerr: \ |
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| 47 | jmpl %o7+8,%g0 ; \ |
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| 48 | nop |
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| 49 | |
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| 50 | /* Support for reentrant syscalls. The "struct _reent *" arg is always the |
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| 51 | the first one. After that we allow up to four additional args. We could |
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| 52 | allow more, but that's all we need for now. |
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| 53 | |
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| 54 | It may seem inefficient to have the reent arg be the first one as it means |
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| 55 | copying all the other args into place (as opposed to making the reent arg |
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| 56 | the last one in which case there wouldn't be any copying). I chose a clean |
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| 57 | design over an extra four instructions in a system call. All other |
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| 58 | reentrant functions use the first arg this way. |
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| 59 | ??? Of course this scheme breaks down if we need to support 6 or more args. |
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| 60 | |
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| 61 | And of course the system calls aren't *really* reentrant. The intent |
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| 62 | is to exercise the reentrancy framework rather than provide/claim |
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| 63 | real reentrancy for this port. |
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| 64 | */ |
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| 65 | |
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| 66 | #define defsyscall_r(name, n) \ |
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| 67 | TEXT_SECTION ; \ |
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| 68 | ALIGN (4) ; \ |
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| 69 | GLOBAL (ASM_SYMBOL (name)) ; \ |
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| 70 | ASM_SYMBOL (name): \ |
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| 71 | mov n,%g1 ; \ |
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| 72 | mov %o0,%o5 ; \ |
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| 73 | mov %o1,%o0 ; \ |
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| 74 | mov %o2,%o1 ; \ |
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| 75 | mov %o3,%o2 ; \ |
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| 76 | mov %o4,%o3 ; \ |
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| 77 | ta SYSCALL_TRAP ; \ |
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| 78 | bcc noerr ; \ |
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| 79 | sethi %hi (ASM_PRIVATE_SYMBOL (cerror_r)),%g1 ; \ |
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| 80 | or %g1,%lo (ASM_PRIVATE_SYMBOL (cerror_r)),%g1 ; \ |
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| 81 | jmpl %g1+%g0,%g0 ; \ |
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| 82 | mov %o5,%o1 ; \ |
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| 83 | noerr: \ |
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| 84 | jmpl %o7+8,%g0 ; \ |
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| 85 | nop |
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| 86 | |
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| 87 | #define seterrno() \ |
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| 88 | sethi %hi (ASM_PRIVATE_SYMBOL (cerror)),%g1 ; \ |
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| 89 | or %g1,%lo (ASM_PRIVATE_SYMBOL (cerror)),%g1 ; \ |
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| 90 | jmpl %g1+%g0,%g0 ; \ |
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| 91 | nop |
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| 92 | |
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| 93 | #endif /* _SYSCALLASM_H_ */ |
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