syscall: always use prlimit for getrlimit/setrlimit on Linux

Linux added the prlimit system call in version 2.6.36.
As our minimum Linux kernel version is now 3.2,
simplify the various getrlimit/setlrimit implementations
to just always use prlimit.

For #67001

Change-Id: I2512c21c947d0bc83f8f9077c143163fd8d83be3
Reviewed-on: https://go-review.googlesource.com/c/go/+/609178
Reviewed-by: Cherry Mui <cherryyz@google.com>
Reviewed-by: Damien Neil <dneil@google.com>
Auto-Submit: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Tobias Klauser <tobias.klauser@gmail.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>

1 files changed, 0 insertions, 90 deletions

diff --git a/src/syscall/syscall_linux_mipsx.go b/src/syscall/syscall_linux_mipsx.go
index 7d4f8f2264..aa08792606 100644
--- a/src/syscall/syscall_linux_mipsx.go
+++ b/src/syscall/syscall_linux_mipsx.go
@@ -117,96 +117,6 @@ func mmap(addr uintptr, length uintptr, prot int, flags int, fd int, offset int6
 	return mmap2(addr, length, prot, flags, fd, page)
 }
 
-const rlimInf32 = ^uint32(0)
-const rlimInf64 = ^uint64(0)
-
-type rlimit32 struct {
-	Cur uint32
-	Max uint32
-}
-
-//sysnb getrlimit(resource int, rlim *rlimit32) (err error) = SYS_GETRLIMIT
-
-func Getrlimit(resource int, rlim *Rlimit) (err error) {
-	err = prlimit(0, resource, nil, rlim)
-	if err != ENOSYS {
-		return err
-	}
-
-	rl := rlimit32{}
-	err = getrlimit(resource, &rl)
-	if err != nil {
-		return
-	}
-
-	if rl.Cur == rlimInf32 {
-		rlim.Cur = rlimInf64
-	} else {
-		rlim.Cur = uint64(rl.Cur)
-	}
-
-	if rl.Max == rlimInf32 {
-		rlim.Max = rlimInf64
-	} else {
-		rlim.Max = uint64(rl.Max)
-	}
-	return
-}
-
-//sysnb setrlimit1(resource int, rlim *rlimit32) (err error) = SYS_SETRLIMIT
-
-func setrlimit(resource int, rlim *Rlimit) (err error) {
-	err = prlimit(0, resource, rlim, nil)
-	if err != ENOSYS {
-		return err
-	}
-
-	rl := rlimit32{}
-	if rlim.Cur == rlimInf64 {
-		rl.Cur = rlimInf32
-	} else if rlim.Cur < uint64(rlimInf32) {
-		rl.Cur = uint32(rlim.Cur)
-	} else {
-		return EINVAL
-	}
-	if rlim.Max == rlimInf64 {
-		rl.Max = rlimInf32
-	} else if rlim.Max < uint64(rlimInf32) {
-		rl.Max = uint32(rlim.Max)
-	} else {
-		return EINVAL
-	}
-
-	return setrlimit1(resource, &rl)
-}
-
-//go:nosplit
-func rawSetrlimit(resource int, rlim *Rlimit) Errno {
-	_, _, errno := RawSyscall6(SYS_PRLIMIT64, 0, uintptr(resource), uintptr(unsafe.Pointer(rlim)), 0, 0, 0)
-	if errno != ENOSYS {
-		return errno
-	}
-
-	rl := rlimit32{}
-	if rlim.Cur == rlimInf64 {
-		rl.Cur = rlimInf32
-	} else if rlim.Cur < uint64(rlimInf32) {
-		rl.Cur = uint32(rlim.Cur)
-	} else {
-		return EINVAL
-	}
-	if rlim.Max == rlimInf64 {
-		rl.Max = rlimInf32
-	} else if rlim.Max < uint64(rlimInf32) {
-		rl.Max = uint32(rlim.Max)
-	} else {
-		return EINVAL
-	}
-
-	_, _, errno = RawSyscall(SYS_SETRLIMIT, uintptr(resource), uintptr(unsafe.Pointer(rlim)), 0)
-	return errno
-}
-
 func (r *PtraceRegs) PC() uint64 { return uint64(r.Regs[64]) }
 
 func (r *PtraceRegs) SetPC(pc uint64) { r.Regs[64] = uint32(pc) }