From dcb18bea6159e841b8c894ac606f471882513429 Mon Sep 17 00:00:00 2001 From: Rich Felker Date: Wed, 10 Apr 2019 19:23:15 -0400 Subject: [PATCH] implement inline 5- and 6-argument syscalls for mips the OABI passes these on the stack, using the convention that their position on the stack is as if the first four arguments (in registers) also had stack slots. originally this was deemed too awkward to do inline, falling back to external __syscall, but it's not that bad and now that external __syscall is being removed, it's necessary. --- arch/mips/syscall_arch.h | 39 +++++++++++++++++++++++++++++++++------ 1 file changed, 33 insertions(+), 6 deletions(-) diff --git a/arch/mips/syscall_arch.h b/arch/mips/syscall_arch.h index 01de67b8..3b33ce18 100644 --- a/arch/mips/syscall_arch.h +++ b/arch/mips/syscall_arch.h @@ -3,8 +3,6 @@ ((union { long long ll; long l[2]; }){ .ll = x }).l[1] #define __SYSCALL_LL_O(x) 0, __SYSCALL_LL_E((x)) -hidden long (__syscall)(long, ...); - #define SYSCALL_RLIM_INFINITY (-1UL/2) #if _MIPSEL || __MIPSEL || __MIPSEL__ @@ -104,8 +102,22 @@ static inline long __syscall4(long n, long a, long b, long c, long d) static inline long __syscall5(long n, long a, long b, long c, long d, long e) { - long r2 = (__syscall)(n, a, b, c, d, e); - if (r2 > -4096UL) return r2; + register long r4 __asm__("$4") = a; + register long r5 __asm__("$5") = b; + register long r6 __asm__("$6") = c; + register long r7 __asm__("$7") = d; + register long r8 __asm__("$8") = e; + register long r2 __asm__("$2"); + __asm__ __volatile__ ( + "subu $sp,$sp,32 ; sw $8,16($sp) ; " + "addu $2,$0,%3 ; syscall ;" + "addu $sp,$sp,32" + : "=&r"(r2), "=r"(r7), "+r"(r8) + : "ir"(n), "0"(r2), "1"(r7), "r"(r4), "r"(r5), "r"(r6) + : "$1", "$3", "$9", "$10", "$11", "$12", "$13", + "$14", "$15", "$24", "$25", "hi", "lo", "memory"); + if (r7) return -r2; + long ret = r2; if (n == SYS_stat64 || n == SYS_fstat64 || n == SYS_lstat64) __stat_fix(b); if (n == SYS_fstatat64) __stat_fix(c); return r2; @@ -113,8 +125,23 @@ static inline long __syscall5(long n, long a, long b, long c, long d, long e) static inline long __syscall6(long n, long a, long b, long c, long d, long e, long f) { - long r2 = (__syscall)(n, a, b, c, d, e, f); - if (r2 > -4096UL) return r2; + register long r4 __asm__("$4") = a; + register long r5 __asm__("$5") = b; + register long r6 __asm__("$6") = c; + register long r7 __asm__("$7") = d; + register long r8 __asm__("$8") = e; + register long r9 __asm__("$9") = f; + register long r2 __asm__("$2"); + __asm__ __volatile__ ( + "subu $sp,$sp,32 ; sw $8,16($sp) ; sw $9,20($sp) ; " + "addu $2,$0,%4 ; syscall ;" + "addu $sp,$sp,32" + : "=&r"(r2), "=r"(r7), "+r"(r8), "+r"(r9) + : "ir"(n), "0"(r2), "1"(r7), "r"(r4), "r"(r5), "r"(r6) + : "$1", "$3", "$10", "$11", "$12", "$13", + "$14", "$15", "$24", "$25", "hi", "lo", "memory"); + if (r7) return -r2; + long ret = r2; if (n == SYS_stat64 || n == SYS_fstat64 || n == SYS_lstat64) __stat_fix(b); if (n == SYS_fstatat64) __stat_fix(c); return r2; -- 2.25.1