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-rw-r--r--src/runtime/internal/sys/consts.go36
-rw-r--r--src/runtime/internal/sys/consts_norace.go9
-rw-r--r--src/runtime/internal/sys/consts_race.go9
-rw-r--r--src/runtime/internal/sys/intrinsics.go208
-rw-r--r--src/runtime/internal/sys/intrinsics_test.go42
-rw-r--r--src/runtime/internal/sys/nih.go41
-rw-r--r--src/runtime/internal/sys/sys.go7
-rw-r--r--src/runtime/internal/syscall/asm_linux_386.s34
-rw-r--r--src/runtime/internal/syscall/asm_linux_amd64.s47
-rw-r--r--src/runtime/internal/syscall/asm_linux_arm.s32
-rw-r--r--src/runtime/internal/syscall/asm_linux_arm64.s29
-rw-r--r--src/runtime/internal/syscall/asm_linux_loong64.s68
-rw-r--r--src/runtime/internal/syscall/asm_linux_mips64x.s30
-rw-r--r--src/runtime/internal/syscall/asm_linux_mipsx.s35
-rw-r--r--src/runtime/internal/syscall/asm_linux_ppc64x.s23
-rw-r--r--src/runtime/internal/syscall/asm_linux_riscv64.s43
-rw-r--r--src/runtime/internal/syscall/asm_linux_s390x.s28
-rw-r--r--src/runtime/internal/syscall/defs_linux_386.go29
-rw-r--r--src/runtime/internal/syscall/defs_linux_amd64.go29
-rw-r--r--src/runtime/internal/syscall/defs_linux_arm.go30
-rw-r--r--src/runtime/internal/syscall/defs_linux_arm64.go30
-rw-r--r--src/runtime/internal/syscall/defs_linux_loong64.go30
-rw-r--r--src/runtime/internal/syscall/defs_linux_mips64x.go32
-rw-r--r--src/runtime/internal/syscall/defs_linux_mipsx.go32
-rw-r--r--src/runtime/internal/syscall/defs_linux_ppc64x.go32
-rw-r--r--src/runtime/internal/syscall/defs_linux_riscv64.go30
-rw-r--r--src/runtime/internal/syscall/defs_linux_s390x.go30
-rw-r--r--src/runtime/internal/syscall/syscall_linux.go62
-rw-r--r--src/runtime/internal/syscall/syscall_linux_test.go19
29 files changed, 1106 insertions, 0 deletions
diff --git a/src/runtime/internal/sys/consts.go b/src/runtime/internal/sys/consts.go
new file mode 100644
index 0000000..98c0f09
--- /dev/null
+++ b/src/runtime/internal/sys/consts.go
@@ -0,0 +1,36 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package sys
+
+import (
+ "internal/goarch"
+ "internal/goos"
+)
+
+// AIX requires a larger stack for syscalls.
+// The race build also needs more stack. See issue 54291.
+// This arithmetic must match that in cmd/internal/objabi/stack.go:stackGuardMultiplier.
+const StackGuardMultiplier = 1 + goos.IsAix + isRace
+
+// DefaultPhysPageSize is the default physical page size.
+const DefaultPhysPageSize = goarch.DefaultPhysPageSize
+
+// PCQuantum is the minimal unit for a program counter (1 on x86, 4 on most other systems).
+// The various PC tables record PC deltas pre-divided by PCQuantum.
+const PCQuantum = goarch.PCQuantum
+
+// Int64Align is the required alignment for a 64-bit integer (4 on 32-bit systems, 8 on 64-bit).
+const Int64Align = goarch.PtrSize
+
+// MinFrameSize is the size of the system-reserved words at the bottom
+// of a frame (just above the architectural stack pointer).
+// It is zero on x86 and PtrSize on most non-x86 (LR-based) systems.
+// On PowerPC it is larger, to cover three more reserved words:
+// the compiler word, the link editor word, and the TOC save word.
+const MinFrameSize = goarch.MinFrameSize
+
+// StackAlign is the required alignment of the SP register.
+// The stack must be at least word aligned, but some architectures require more.
+const StackAlign = goarch.StackAlign
diff --git a/src/runtime/internal/sys/consts_norace.go b/src/runtime/internal/sys/consts_norace.go
new file mode 100644
index 0000000..a9613b8
--- /dev/null
+++ b/src/runtime/internal/sys/consts_norace.go
@@ -0,0 +1,9 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build !race
+
+package sys
+
+const isRace = 0
diff --git a/src/runtime/internal/sys/consts_race.go b/src/runtime/internal/sys/consts_race.go
new file mode 100644
index 0000000..f824fb3
--- /dev/null
+++ b/src/runtime/internal/sys/consts_race.go
@@ -0,0 +1,9 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build race
+
+package sys
+
+const isRace = 1
diff --git a/src/runtime/internal/sys/intrinsics.go b/src/runtime/internal/sys/intrinsics.go
new file mode 100644
index 0000000..e6a3758
--- /dev/null
+++ b/src/runtime/internal/sys/intrinsics.go
@@ -0,0 +1,208 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package sys
+
+// Copied from math/bits to avoid dependence.
+
+var deBruijn32tab = [32]byte{
+ 0, 1, 28, 2, 29, 14, 24, 3, 30, 22, 20, 15, 25, 17, 4, 8,
+ 31, 27, 13, 23, 21, 19, 16, 7, 26, 12, 18, 6, 11, 5, 10, 9,
+}
+
+const deBruijn32 = 0x077CB531
+
+var deBruijn64tab = [64]byte{
+ 0, 1, 56, 2, 57, 49, 28, 3, 61, 58, 42, 50, 38, 29, 17, 4,
+ 62, 47, 59, 36, 45, 43, 51, 22, 53, 39, 33, 30, 24, 18, 12, 5,
+ 63, 55, 48, 27, 60, 41, 37, 16, 46, 35, 44, 21, 52, 32, 23, 11,
+ 54, 26, 40, 15, 34, 20, 31, 10, 25, 14, 19, 9, 13, 8, 7, 6,
+}
+
+const deBruijn64 = 0x03f79d71b4ca8b09
+
+const ntz8tab = "" +
+ "\x08\x00\x01\x00\x02\x00\x01\x00\x03\x00\x01\x00\x02\x00\x01\x00" +
+ "\x04\x00\x01\x00\x02\x00\x01\x00\x03\x00\x01\x00\x02\x00\x01\x00" +
+ "\x05\x00\x01\x00\x02\x00\x01\x00\x03\x00\x01\x00\x02\x00\x01\x00" +
+ "\x04\x00\x01\x00\x02\x00\x01\x00\x03\x00\x01\x00\x02\x00\x01\x00" +
+ "\x06\x00\x01\x00\x02\x00\x01\x00\x03\x00\x01\x00\x02\x00\x01\x00" +
+ "\x04\x00\x01\x00\x02\x00\x01\x00\x03\x00\x01\x00\x02\x00\x01\x00" +
+ "\x05\x00\x01\x00\x02\x00\x01\x00\x03\x00\x01\x00\x02\x00\x01\x00" +
+ "\x04\x00\x01\x00\x02\x00\x01\x00\x03\x00\x01\x00\x02\x00\x01\x00" +
+ "\x07\x00\x01\x00\x02\x00\x01\x00\x03\x00\x01\x00\x02\x00\x01\x00" +
+ "\x04\x00\x01\x00\x02\x00\x01\x00\x03\x00\x01\x00\x02\x00\x01\x00" +
+ "\x05\x00\x01\x00\x02\x00\x01\x00\x03\x00\x01\x00\x02\x00\x01\x00" +
+ "\x04\x00\x01\x00\x02\x00\x01\x00\x03\x00\x01\x00\x02\x00\x01\x00" +
+ "\x06\x00\x01\x00\x02\x00\x01\x00\x03\x00\x01\x00\x02\x00\x01\x00" +
+ "\x04\x00\x01\x00\x02\x00\x01\x00\x03\x00\x01\x00\x02\x00\x01\x00" +
+ "\x05\x00\x01\x00\x02\x00\x01\x00\x03\x00\x01\x00\x02\x00\x01\x00" +
+ "\x04\x00\x01\x00\x02\x00\x01\x00\x03\x00\x01\x00\x02\x00\x01\x00"
+
+// TrailingZeros32 returns the number of trailing zero bits in x; the result is 32 for x == 0.
+func TrailingZeros32(x uint32) int {
+ if x == 0 {
+ return 32
+ }
+ // see comment in TrailingZeros64
+ return int(deBruijn32tab[(x&-x)*deBruijn32>>(32-5)])
+}
+
+// TrailingZeros64 returns the number of trailing zero bits in x; the result is 64 for x == 0.
+func TrailingZeros64(x uint64) int {
+ if x == 0 {
+ return 64
+ }
+ // If popcount is fast, replace code below with return popcount(^x & (x - 1)).
+ //
+ // x & -x leaves only the right-most bit set in the word. Let k be the
+ // index of that bit. Since only a single bit is set, the value is two
+ // to the power of k. Multiplying by a power of two is equivalent to
+ // left shifting, in this case by k bits. The de Bruijn (64 bit) constant
+ // is such that all six bit, consecutive substrings are distinct.
+ // Therefore, if we have a left shifted version of this constant we can
+ // find by how many bits it was shifted by looking at which six bit
+ // substring ended up at the top of the word.
+ // (Knuth, volume 4, section 7.3.1)
+ return int(deBruijn64tab[(x&-x)*deBruijn64>>(64-6)])
+}
+
+// TrailingZeros8 returns the number of trailing zero bits in x; the result is 8 for x == 0.
+func TrailingZeros8(x uint8) int {
+ return int(ntz8tab[x])
+}
+
+const len8tab = "" +
+ "\x00\x01\x02\x02\x03\x03\x03\x03\x04\x04\x04\x04\x04\x04\x04\x04" +
+ "\x05\x05\x05\x05\x05\x05\x05\x05\x05\x05\x05\x05\x05\x05\x05\x05" +
+ "\x06\x06\x06\x06\x06\x06\x06\x06\x06\x06\x06\x06\x06\x06\x06\x06" +
+ "\x06\x06\x06\x06\x06\x06\x06\x06\x06\x06\x06\x06\x06\x06\x06\x06" +
+ "\x07\x07\x07\x07\x07\x07\x07\x07\x07\x07\x07\x07\x07\x07\x07\x07" +
+ "\x07\x07\x07\x07\x07\x07\x07\x07\x07\x07\x07\x07\x07\x07\x07\x07" +
+ "\x07\x07\x07\x07\x07\x07\x07\x07\x07\x07\x07\x07\x07\x07\x07\x07" +
+ "\x07\x07\x07\x07\x07\x07\x07\x07\x07\x07\x07\x07\x07\x07\x07\x07" +
+ "\x08\x08\x08\x08\x08\x08\x08\x08\x08\x08\x08\x08\x08\x08\x08\x08" +
+ "\x08\x08\x08\x08\x08\x08\x08\x08\x08\x08\x08\x08\x08\x08\x08\x08" +
+ "\x08\x08\x08\x08\x08\x08\x08\x08\x08\x08\x08\x08\x08\x08\x08\x08" +
+ "\x08\x08\x08\x08\x08\x08\x08\x08\x08\x08\x08\x08\x08\x08\x08\x08" +
+ "\x08\x08\x08\x08\x08\x08\x08\x08\x08\x08\x08\x08\x08\x08\x08\x08" +
+ "\x08\x08\x08\x08\x08\x08\x08\x08\x08\x08\x08\x08\x08\x08\x08\x08" +
+ "\x08\x08\x08\x08\x08\x08\x08\x08\x08\x08\x08\x08\x08\x08\x08\x08" +
+ "\x08\x08\x08\x08\x08\x08\x08\x08\x08\x08\x08\x08\x08\x08\x08\x08"
+
+// Len64 returns the minimum number of bits required to represent x; the result is 0 for x == 0.
+//
+// nosplit because this is used in src/runtime/histogram.go, which make run in sensitive contexts.
+//
+//go:nosplit
+func Len64(x uint64) (n int) {
+ if x >= 1<<32 {
+ x >>= 32
+ n = 32
+ }
+ if x >= 1<<16 {
+ x >>= 16
+ n += 16
+ }
+ if x >= 1<<8 {
+ x >>= 8
+ n += 8
+ }
+ return n + int(len8tab[x])
+}
+
+// --- OnesCount ---
+
+const m0 = 0x5555555555555555 // 01010101 ...
+const m1 = 0x3333333333333333 // 00110011 ...
+const m2 = 0x0f0f0f0f0f0f0f0f // 00001111 ...
+
+// OnesCount64 returns the number of one bits ("population count") in x.
+func OnesCount64(x uint64) int {
+ // Implementation: Parallel summing of adjacent bits.
+ // See "Hacker's Delight", Chap. 5: Counting Bits.
+ // The following pattern shows the general approach:
+ //
+ // x = x>>1&(m0&m) + x&(m0&m)
+ // x = x>>2&(m1&m) + x&(m1&m)
+ // x = x>>4&(m2&m) + x&(m2&m)
+ // x = x>>8&(m3&m) + x&(m3&m)
+ // x = x>>16&(m4&m) + x&(m4&m)
+ // x = x>>32&(m5&m) + x&(m5&m)
+ // return int(x)
+ //
+ // Masking (& operations) can be left away when there's no
+ // danger that a field's sum will carry over into the next
+ // field: Since the result cannot be > 64, 8 bits is enough
+ // and we can ignore the masks for the shifts by 8 and up.
+ // Per "Hacker's Delight", the first line can be simplified
+ // more, but it saves at best one instruction, so we leave
+ // it alone for clarity.
+ const m = 1<<64 - 1
+ x = x>>1&(m0&m) + x&(m0&m)
+ x = x>>2&(m1&m) + x&(m1&m)
+ x = (x>>4 + x) & (m2 & m)
+ x += x >> 8
+ x += x >> 16
+ x += x >> 32
+ return int(x) & (1<<7 - 1)
+}
+
+// LeadingZeros64 returns the number of leading zero bits in x; the result is 64 for x == 0.
+func LeadingZeros64(x uint64) int { return 64 - Len64(x) }
+
+// LeadingZeros8 returns the number of leading zero bits in x; the result is 8 for x == 0.
+func LeadingZeros8(x uint8) int { return 8 - Len8(x) }
+
+// Len8 returns the minimum number of bits required to represent x; the result is 0 for x == 0.
+func Len8(x uint8) int {
+ return int(len8tab[x])
+}
+
+// Bswap64 returns its input with byte order reversed
+// 0x0102030405060708 -> 0x0807060504030201
+func Bswap64(x uint64) uint64 {
+ c8 := uint64(0x00ff00ff00ff00ff)
+ a := x >> 8 & c8
+ b := (x & c8) << 8
+ x = a | b
+ c16 := uint64(0x0000ffff0000ffff)
+ a = x >> 16 & c16
+ b = (x & c16) << 16
+ x = a | b
+ c32 := uint64(0x00000000ffffffff)
+ a = x >> 32 & c32
+ b = (x & c32) << 32
+ x = a | b
+ return x
+}
+
+// Bswap32 returns its input with byte order reversed
+// 0x01020304 -> 0x04030201
+func Bswap32(x uint32) uint32 {
+ c8 := uint32(0x00ff00ff)
+ a := x >> 8 & c8
+ b := (x & c8) << 8
+ x = a | b
+ c16 := uint32(0x0000ffff)
+ a = x >> 16 & c16
+ b = (x & c16) << 16
+ x = a | b
+ return x
+}
+
+// Prefetch prefetches data from memory addr to cache
+//
+// AMD64: Produce PREFETCHT0 instruction
+//
+// ARM64: Produce PRFM instruction with PLDL1KEEP option
+func Prefetch(addr uintptr) {}
+
+// PrefetchStreamed prefetches data from memory addr, with a hint that this data is being streamed.
+// That is, it is likely to be accessed very soon, but only once. If possible, this will avoid polluting the cache.
+//
+// AMD64: Produce PREFETCHNTA instruction
+//
+// ARM64: Produce PRFM instruction with PLDL1STRM option
+func PrefetchStreamed(addr uintptr) {}
diff --git a/src/runtime/internal/sys/intrinsics_test.go b/src/runtime/internal/sys/intrinsics_test.go
new file mode 100644
index 0000000..6799885
--- /dev/null
+++ b/src/runtime/internal/sys/intrinsics_test.go
@@ -0,0 +1,42 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package sys_test
+
+import (
+ "runtime/internal/sys"
+ "testing"
+)
+
+func TestTrailingZeros64(t *testing.T) {
+ for i := 0; i <= 64; i++ {
+ x := uint64(5) << uint(i)
+ if got := sys.TrailingZeros64(x); got != i {
+ t.Errorf("TrailingZeros64(%d)=%d, want %d", x, got, i)
+ }
+ }
+}
+func TestTrailingZeros32(t *testing.T) {
+ for i := 0; i <= 32; i++ {
+ x := uint32(5) << uint(i)
+ if got := sys.TrailingZeros32(x); got != i {
+ t.Errorf("TrailingZeros32(%d)=%d, want %d", x, got, i)
+ }
+ }
+}
+
+func TestBswap64(t *testing.T) {
+ x := uint64(0x1122334455667788)
+ y := sys.Bswap64(x)
+ if y != 0x8877665544332211 {
+ t.Errorf("Bswap(%x)=%x, want 0x8877665544332211", x, y)
+ }
+}
+func TestBswap32(t *testing.T) {
+ x := uint32(0x11223344)
+ y := sys.Bswap32(x)
+ if y != 0x44332211 {
+ t.Errorf("Bswap(%x)=%x, want 0x44332211", x, y)
+ }
+}
diff --git a/src/runtime/internal/sys/nih.go b/src/runtime/internal/sys/nih.go
new file mode 100644
index 0000000..17eab67
--- /dev/null
+++ b/src/runtime/internal/sys/nih.go
@@ -0,0 +1,41 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package sys
+
+// NOTE: keep in sync with cmd/compile/internal/types.CalcSize
+// to make the compiler recognize this as an intrinsic type.
+type nih struct{}
+
+// NotInHeap is a type must never be allocated from the GC'd heap or on the stack,
+// and is called not-in-heap.
+//
+// Other types can embed NotInHeap to make it not-in-heap. Specifically, pointers
+// to these types must always fail the `runtime.inheap` check. The type may be used
+// for global variables, or for objects in unmanaged memory (e.g., allocated with
+// `sysAlloc`, `persistentalloc`, r`fixalloc`, or from a manually-managed span).
+//
+// Specifically:
+//
+// 1. `new(T)`, `make([]T)`, `append([]T, ...)` and implicit heap
+// allocation of T are disallowed. (Though implicit allocations are
+// disallowed in the runtime anyway.)
+//
+// 2. A pointer to a regular type (other than `unsafe.Pointer`) cannot be
+// converted to a pointer to a not-in-heap type, even if they have the
+// same underlying type.
+//
+// 3. Any type that containing a not-in-heap type is itself considered as not-in-heap.
+//
+// - Structs and arrays are not-in-heap if their elements are not-in-heap.
+// - Maps and channels contains no-in-heap types are disallowed.
+//
+// 4. Write barriers on pointers to not-in-heap types can be omitted.
+//
+// The last point is the real benefit of NotInHeap. The runtime uses
+// it for low-level internal structures to avoid memory barriers in the
+// scheduler and the memory allocator where they are illegal or simply
+// inefficient. This mechanism is reasonably safe and does not compromise
+// the readability of the runtime.
+type NotInHeap struct{ _ nih }
diff --git a/src/runtime/internal/sys/sys.go b/src/runtime/internal/sys/sys.go
new file mode 100644
index 0000000..694101d
--- /dev/null
+++ b/src/runtime/internal/sys/sys.go
@@ -0,0 +1,7 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// package sys contains system- and configuration- and architecture-specific
+// constants used by the runtime.
+package sys
diff --git a/src/runtime/internal/syscall/asm_linux_386.s b/src/runtime/internal/syscall/asm_linux_386.s
new file mode 100644
index 0000000..15aae4d
--- /dev/null
+++ b/src/runtime/internal/syscall/asm_linux_386.s
@@ -0,0 +1,34 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "textflag.h"
+
+// See ../sys_linux_386.s for the reason why we always use int 0x80
+// instead of the glibc-specific "CALL 0x10(GS)".
+#define INVOKE_SYSCALL INT $0x80
+
+// func Syscall6(num, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2, errno uintptr)
+//
+// Syscall # in AX, args in BX CX DX SI DI BP, return in AX
+TEXT ·Syscall6(SB),NOSPLIT,$0-40
+ MOVL num+0(FP), AX // syscall entry
+ MOVL a1+4(FP), BX
+ MOVL a2+8(FP), CX
+ MOVL a3+12(FP), DX
+ MOVL a4+16(FP), SI
+ MOVL a5+20(FP), DI
+ MOVL a6+24(FP), BP
+ INVOKE_SYSCALL
+ CMPL AX, $0xfffff001
+ JLS ok
+ MOVL $-1, r1+28(FP)
+ MOVL $0, r2+32(FP)
+ NEGL AX
+ MOVL AX, errno+36(FP)
+ RET
+ok:
+ MOVL AX, r1+28(FP)
+ MOVL DX, r2+32(FP)
+ MOVL $0, errno+36(FP)
+ RET
diff --git a/src/runtime/internal/syscall/asm_linux_amd64.s b/src/runtime/internal/syscall/asm_linux_amd64.s
new file mode 100644
index 0000000..3740ef1
--- /dev/null
+++ b/src/runtime/internal/syscall/asm_linux_amd64.s
@@ -0,0 +1,47 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "textflag.h"
+
+// func Syscall6(num, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2, errno uintptr)
+//
+// We need to convert to the syscall ABI.
+//
+// arg | ABIInternal | Syscall
+// ---------------------------
+// num | AX | AX
+// a1 | BX | DI
+// a2 | CX | SI
+// a3 | DI | DX
+// a4 | SI | R10
+// a5 | R8 | R8
+// a6 | R9 | R9
+//
+// r1 | AX | AX
+// r2 | BX | DX
+// err | CX | part of AX
+//
+// Note that this differs from "standard" ABI convention, which would pass 4th
+// arg in CX, not R10.
+TEXT ·Syscall6<ABIInternal>(SB),NOSPLIT,$0
+ // a6 already in R9.
+ // a5 already in R8.
+ MOVQ SI, R10 // a4
+ MOVQ DI, DX // a3
+ MOVQ CX, SI // a2
+ MOVQ BX, DI // a1
+ // num already in AX.
+ SYSCALL
+ CMPQ AX, $0xfffffffffffff001
+ JLS ok
+ NEGQ AX
+ MOVQ AX, CX // errno
+ MOVQ $-1, AX // r1
+ MOVQ $0, BX // r2
+ RET
+ok:
+ // r1 already in AX.
+ MOVQ DX, BX // r2
+ MOVQ $0, CX // errno
+ RET
diff --git a/src/runtime/internal/syscall/asm_linux_arm.s b/src/runtime/internal/syscall/asm_linux_arm.s
new file mode 100644
index 0000000..dbf1826
--- /dev/null
+++ b/src/runtime/internal/syscall/asm_linux_arm.s
@@ -0,0 +1,32 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "textflag.h"
+
+// func Syscall6(num, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2, errno uintptr)
+TEXT ·Syscall6(SB),NOSPLIT,$0-40
+ MOVW num+0(FP), R7 // syscall entry
+ MOVW a1+4(FP), R0
+ MOVW a2+8(FP), R1
+ MOVW a3+12(FP), R2
+ MOVW a4+16(FP), R3
+ MOVW a5+20(FP), R4
+ MOVW a6+24(FP), R5
+ SWI $0
+ MOVW $0xfffff001, R6
+ CMP R6, R0
+ BLS ok
+ MOVW $-1, R1
+ MOVW R1, r1+28(FP)
+ MOVW $0, R2
+ MOVW R2, r2+32(FP)
+ RSB $0, R0, R0
+ MOVW R0, errno+36(FP)
+ RET
+ok:
+ MOVW R0, r1+28(FP)
+ MOVW R1, r2+32(FP)
+ MOVW $0, R0
+ MOVW R0, errno+36(FP)
+ RET
diff --git a/src/runtime/internal/syscall/asm_linux_arm64.s b/src/runtime/internal/syscall/asm_linux_arm64.s
new file mode 100644
index 0000000..83e862f
--- /dev/null
+++ b/src/runtime/internal/syscall/asm_linux_arm64.s
@@ -0,0 +1,29 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "textflag.h"
+
+// func Syscall6(num, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2, errno uintptr)
+TEXT ·Syscall6(SB),NOSPLIT,$0-80
+ MOVD num+0(FP), R8 // syscall entry
+ MOVD a1+8(FP), R0
+ MOVD a2+16(FP), R1
+ MOVD a3+24(FP), R2
+ MOVD a4+32(FP), R3
+ MOVD a5+40(FP), R4
+ MOVD a6+48(FP), R5
+ SVC
+ CMN $4095, R0
+ BCC ok
+ MOVD $-1, R4
+ MOVD R4, r1+56(FP)
+ MOVD ZR, r2+64(FP)
+ NEG R0, R0
+ MOVD R0, errno+72(FP)
+ RET
+ok:
+ MOVD R0, r1+56(FP)
+ MOVD R1, r2+64(FP)
+ MOVD ZR, errno+72(FP)
+ RET
diff --git a/src/runtime/internal/syscall/asm_linux_loong64.s b/src/runtime/internal/syscall/asm_linux_loong64.s
new file mode 100644
index 0000000..11c5bc2
--- /dev/null
+++ b/src/runtime/internal/syscall/asm_linux_loong64.s
@@ -0,0 +1,68 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "textflag.h"
+
+// func Syscall6(num, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2, errno uintptr)
+//
+// We need to convert to the syscall ABI.
+//
+// arg | ABIInternal | Syscall
+// ---------------------------
+// num | R4 | R11
+// a1 | R5 | R4
+// a2 | R6 | R5
+// a3 | R7 | R6
+// a4 | R8 | R7
+// a5 | R9 | R8
+// a6 | R10 | R9
+//
+// r1 | R4 | R4
+// r2 | R5 | R5
+// err | R6 | part of R4
+TEXT ·Syscall6<ABIInternal>(SB),NOSPLIT,$0-80
+#ifdef GOEXPERIMENT_regabiargs
+ MOVV R4, R11 // syscall entry
+ MOVV R5, R4
+ MOVV R6, R5
+ MOVV R7, R6
+ MOVV R8, R7
+ MOVV R9, R8
+ MOVV R10, R9
+#else
+ MOVV num+0(FP), R11 // syscall entry
+ MOVV a1+8(FP), R4
+ MOVV a2+16(FP), R5
+ MOVV a3+24(FP), R6
+ MOVV a4+32(FP), R7
+ MOVV a5+40(FP), R8
+ MOVV a6+48(FP), R9
+#endif
+ SYSCALL
+#ifdef GOEXPERIMENT_regabiargs
+ MOVV R0, R5 // r2 is not used. Always set to 0.
+ MOVW $-4096, R12
+ BGEU R12, R4, ok
+ SUBVU R4, R0, R6 // errno
+ MOVV $-1, R4 // r1
+#else
+ MOVW $-4096, R12
+ BGEU R12, R4, ok
+ MOVV $-1, R12
+ MOVV R12, r1+56(FP)
+ MOVV R0, r2+64(FP)
+ SUBVU R4, R0, R4
+ MOVV R4, errno+72(FP)
+#endif
+ RET
+ok:
+#ifdef GOEXPERIMENT_regabiargs
+ // r1 already in R4
+ MOVV R0, R6 // errno
+#else
+ MOVV R4, r1+56(FP)
+ MOVV R0, r2+64(FP) // r2 is not used. Always set to 0.
+ MOVV R0, errno+72(FP)
+#endif
+ RET
diff --git a/src/runtime/internal/syscall/asm_linux_mips64x.s b/src/runtime/internal/syscall/asm_linux_mips64x.s
new file mode 100644
index 0000000..6b7c524
--- /dev/null
+++ b/src/runtime/internal/syscall/asm_linux_mips64x.s
@@ -0,0 +1,30 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build linux && (mips64 || mips64le)
+
+#include "textflag.h"
+
+// func Syscall6(num, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2, errno uintptr)
+TEXT ·Syscall6(SB),NOSPLIT,$0-80
+ MOVV num+0(FP), R2 // syscall entry
+ MOVV a1+8(FP), R4
+ MOVV a2+16(FP), R5
+ MOVV a3+24(FP), R6
+ MOVV a4+32(FP), R7
+ MOVV a5+40(FP), R8
+ MOVV a6+48(FP), R9
+ MOVV R0, R3 // reset R3 to 0 as 1-ret SYSCALL keeps it
+ SYSCALL
+ BEQ R7, ok
+ MOVV $-1, R1
+ MOVV R1, r1+56(FP)
+ MOVV R0, r2+64(FP)
+ MOVV R2, errno+72(FP)
+ RET
+ok:
+ MOVV R2, r1+56(FP)
+ MOVV R3, r2+64(FP)
+ MOVV R0, errno+72(FP)
+ RET
diff --git a/src/runtime/internal/syscall/asm_linux_mipsx.s b/src/runtime/internal/syscall/asm_linux_mipsx.s
new file mode 100644
index 0000000..561310f
--- /dev/null
+++ b/src/runtime/internal/syscall/asm_linux_mipsx.s
@@ -0,0 +1,35 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build linux && (mips || mipsle)
+
+#include "textflag.h"
+
+// func Syscall6(num, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2, errno uintptr)
+//
+// The 5th and 6th arg go at sp+16, sp+20.
+// Note that frame size of 20 means that 24 bytes gets reserved on stack.
+TEXT ·Syscall6(SB),NOSPLIT,$20-40
+ MOVW num+0(FP), R2 // syscall entry
+ MOVW a1+4(FP), R4
+ MOVW a2+8(FP), R5
+ MOVW a3+12(FP), R6
+ MOVW a4+16(FP), R7
+ MOVW a5+20(FP), R8
+ MOVW a6+24(FP), R9
+ MOVW R8, 16(R29)
+ MOVW R9, 20(R29)
+ MOVW R0, R3 // reset R3 to 0 as 1-ret SYSCALL keeps it
+ SYSCALL
+ BEQ R7, ok
+ MOVW $-1, R1
+ MOVW R1, r1+28(FP)
+ MOVW R0, r2+32(FP)
+ MOVW R2, errno+36(FP)
+ RET
+ok:
+ MOVW R2, r1+28(FP)
+ MOVW R3, r2+32(FP)
+ MOVW R0, errno+36(FP)
+ RET
diff --git a/src/runtime/internal/syscall/asm_linux_ppc64x.s b/src/runtime/internal/syscall/asm_linux_ppc64x.s
new file mode 100644
index 0000000..3e985ed
--- /dev/null
+++ b/src/runtime/internal/syscall/asm_linux_ppc64x.s
@@ -0,0 +1,23 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build linux && (ppc64 || ppc64le)
+
+#include "textflag.h"
+
+// func Syscall6(num, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2, errno uintptr)
+TEXT ·Syscall6<ABIInternal>(SB),NOSPLIT,$0-80
+ MOVD R3, R10 // Move syscall number to R10. SYSCALL will move it R0, and restore R0.
+ MOVD R4, R3
+ MOVD R5, R4
+ MOVD R6, R5
+ MOVD R7, R6
+ MOVD R8, R7
+ MOVD R9, R8
+ SYSCALL R10
+ MOVD $-1, R6
+ ISEL CR0SO, R3, R0, R5 // errno = (error) ? R3 : 0
+ ISEL CR0SO, R6, R3, R3 // r1 = (error) ? -1 : 0
+ MOVD $0, R4 // r2 is not used on linux/ppc64
+ RET
diff --git a/src/runtime/internal/syscall/asm_linux_riscv64.s b/src/runtime/internal/syscall/asm_linux_riscv64.s
new file mode 100644
index 0000000..15e50ec
--- /dev/null
+++ b/src/runtime/internal/syscall/asm_linux_riscv64.s
@@ -0,0 +1,43 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "textflag.h"
+
+// func Syscall6(num, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2, errno uintptr)
+//
+// We need to convert to the syscall ABI.
+//
+// arg | ABIInternal | Syscall
+// ---------------------------
+// num | A0 | A7
+// a1 | A1 | A0
+// a2 | A2 | A1
+// a3 | A3 | A2
+// a4 | A4 | A3
+// a5 | A5 | A4
+// a6 | A6 | A5
+//
+// r1 | A0 | A0
+// r2 | A1 | A1
+// err | A2 | part of A0
+TEXT ·Syscall6<ABIInternal>(SB),NOSPLIT,$0-80
+ MOV A0, A7
+ MOV A1, A0
+ MOV A2, A1
+ MOV A3, A2
+ MOV A4, A3
+ MOV A5, A4
+ MOV A6, A5
+ ECALL
+ MOV $-4096, T0
+ BLTU T0, A0, err
+ // r1 already in A0
+ // r2 already in A1
+ MOV ZERO, A2 // errno
+ RET
+err:
+ SUB A0, ZERO, A2 // errno
+ MOV $-1, A0 // r1
+ MOV ZERO, A1 // r2
+ RET
diff --git a/src/runtime/internal/syscall/asm_linux_s390x.s b/src/runtime/internal/syscall/asm_linux_s390x.s
new file mode 100644
index 0000000..1b27f29
--- /dev/null
+++ b/src/runtime/internal/syscall/asm_linux_s390x.s
@@ -0,0 +1,28 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "textflag.h"
+
+// func Syscall6(num, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2, errno uintptr)
+TEXT ·Syscall6(SB),NOSPLIT,$0-80
+ MOVD num+0(FP), R1 // syscall entry
+ MOVD a1+8(FP), R2
+ MOVD a2+16(FP), R3
+ MOVD a3+24(FP), R4
+ MOVD a4+32(FP), R5
+ MOVD a5+40(FP), R6
+ MOVD a6+48(FP), R7
+ SYSCALL
+ MOVD $0xfffffffffffff001, R8
+ CMPUBLT R2, R8, ok
+ MOVD $-1, r1+56(FP)
+ MOVD $0, r2+64(FP)
+ NEG R2, R2
+ MOVD R2, errno+72(FP)
+ RET
+ok:
+ MOVD R2, r1+56(FP)
+ MOVD R3, r2+64(FP)
+ MOVD $0, errno+72(FP)
+ RET
diff --git a/src/runtime/internal/syscall/defs_linux_386.go b/src/runtime/internal/syscall/defs_linux_386.go
new file mode 100644
index 0000000..dc723a6
--- /dev/null
+++ b/src/runtime/internal/syscall/defs_linux_386.go
@@ -0,0 +1,29 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package syscall
+
+const (
+ SYS_FCNTL = 55
+ SYS_EPOLL_CTL = 255
+ SYS_EPOLL_PWAIT = 319
+ SYS_EPOLL_CREATE1 = 329
+ SYS_EPOLL_PWAIT2 = 441
+
+ EPOLLIN = 0x1
+ EPOLLOUT = 0x4
+ EPOLLERR = 0x8
+ EPOLLHUP = 0x10
+ EPOLLRDHUP = 0x2000
+ EPOLLET = 0x80000000
+ EPOLL_CLOEXEC = 0x80000
+ EPOLL_CTL_ADD = 0x1
+ EPOLL_CTL_DEL = 0x2
+ EPOLL_CTL_MOD = 0x3
+)
+
+type EpollEvent struct {
+ Events uint32
+ Data [8]byte // to match amd64
+}
diff --git a/src/runtime/internal/syscall/defs_linux_amd64.go b/src/runtime/internal/syscall/defs_linux_amd64.go
new file mode 100644
index 0000000..886eb5b
--- /dev/null
+++ b/src/runtime/internal/syscall/defs_linux_amd64.go
@@ -0,0 +1,29 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package syscall
+
+const (
+ SYS_FCNTL = 72
+ SYS_EPOLL_CTL = 233
+ SYS_EPOLL_PWAIT = 281
+ SYS_EPOLL_CREATE1 = 291
+ SYS_EPOLL_PWAIT2 = 441
+
+ EPOLLIN = 0x1
+ EPOLLOUT = 0x4
+ EPOLLERR = 0x8
+ EPOLLHUP = 0x10
+ EPOLLRDHUP = 0x2000
+ EPOLLET = 0x80000000
+ EPOLL_CLOEXEC = 0x80000
+ EPOLL_CTL_ADD = 0x1
+ EPOLL_CTL_DEL = 0x2
+ EPOLL_CTL_MOD = 0x3
+)
+
+type EpollEvent struct {
+ Events uint32
+ Data [8]byte // unaligned uintptr
+}
diff --git a/src/runtime/internal/syscall/defs_linux_arm.go b/src/runtime/internal/syscall/defs_linux_arm.go
new file mode 100644
index 0000000..8f812a2
--- /dev/null
+++ b/src/runtime/internal/syscall/defs_linux_arm.go
@@ -0,0 +1,30 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package syscall
+
+const (
+ SYS_FCNTL = 55
+ SYS_EPOLL_CTL = 251
+ SYS_EPOLL_PWAIT = 346
+ SYS_EPOLL_CREATE1 = 357
+ SYS_EPOLL_PWAIT2 = 441
+
+ EPOLLIN = 0x1
+ EPOLLOUT = 0x4
+ EPOLLERR = 0x8
+ EPOLLHUP = 0x10
+ EPOLLRDHUP = 0x2000
+ EPOLLET = 0x80000000
+ EPOLL_CLOEXEC = 0x80000
+ EPOLL_CTL_ADD = 0x1
+ EPOLL_CTL_DEL = 0x2
+ EPOLL_CTL_MOD = 0x3
+)
+
+type EpollEvent struct {
+ Events uint32
+ _pad uint32
+ Data [8]byte // to match amd64
+}
diff --git a/src/runtime/internal/syscall/defs_linux_arm64.go b/src/runtime/internal/syscall/defs_linux_arm64.go
new file mode 100644
index 0000000..48e11b0
--- /dev/null
+++ b/src/runtime/internal/syscall/defs_linux_arm64.go
@@ -0,0 +1,30 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package syscall
+
+const (
+ SYS_EPOLL_CREATE1 = 20
+ SYS_EPOLL_CTL = 21
+ SYS_EPOLL_PWAIT = 22
+ SYS_FCNTL = 25
+ SYS_EPOLL_PWAIT2 = 441
+
+ EPOLLIN = 0x1
+ EPOLLOUT = 0x4
+ EPOLLERR = 0x8
+ EPOLLHUP = 0x10
+ EPOLLRDHUP = 0x2000
+ EPOLLET = 0x80000000
+ EPOLL_CLOEXEC = 0x80000
+ EPOLL_CTL_ADD = 0x1
+ EPOLL_CTL_DEL = 0x2
+ EPOLL_CTL_MOD = 0x3
+)
+
+type EpollEvent struct {
+ Events uint32
+ _pad uint32
+ Data [8]byte // to match amd64
+}
diff --git a/src/runtime/internal/syscall/defs_linux_loong64.go b/src/runtime/internal/syscall/defs_linux_loong64.go
new file mode 100644
index 0000000..b78ef81
--- /dev/null
+++ b/src/runtime/internal/syscall/defs_linux_loong64.go
@@ -0,0 +1,30 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package syscall
+
+const (
+ SYS_EPOLL_CREATE1 = 20
+ SYS_EPOLL_CTL = 21
+ SYS_EPOLL_PWAIT = 22
+ SYS_FCNTL = 25
+ SYS_EPOLL_PWAIT2 = 441
+
+ EPOLLIN = 0x1
+ EPOLLOUT = 0x4
+ EPOLLERR = 0x8
+ EPOLLHUP = 0x10
+ EPOLLRDHUP = 0x2000
+ EPOLLET = 0x80000000
+ EPOLL_CLOEXEC = 0x80000
+ EPOLL_CTL_ADD = 0x1
+ EPOLL_CTL_DEL = 0x2
+ EPOLL_CTL_MOD = 0x3
+)
+
+type EpollEvent struct {
+ Events uint32
+ pad_cgo_0 [4]byte
+ Data [8]byte // unaligned uintptr
+}
diff --git a/src/runtime/internal/syscall/defs_linux_mips64x.go b/src/runtime/internal/syscall/defs_linux_mips64x.go
new file mode 100644
index 0000000..92b49ca
--- /dev/null
+++ b/src/runtime/internal/syscall/defs_linux_mips64x.go
@@ -0,0 +1,32 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build linux && (mips64 || mips64le)
+
+package syscall
+
+const (
+ SYS_FCNTL = 5070
+ SYS_EPOLL_CTL = 5208
+ SYS_EPOLL_PWAIT = 5272
+ SYS_EPOLL_CREATE1 = 5285
+ SYS_EPOLL_PWAIT2 = 5441
+
+ EPOLLIN = 0x1
+ EPOLLOUT = 0x4
+ EPOLLERR = 0x8
+ EPOLLHUP = 0x10
+ EPOLLRDHUP = 0x2000
+ EPOLLET = 0x80000000
+ EPOLL_CLOEXEC = 0x80000
+ EPOLL_CTL_ADD = 0x1
+ EPOLL_CTL_DEL = 0x2
+ EPOLL_CTL_MOD = 0x3
+)
+
+type EpollEvent struct {
+ Events uint32
+ pad_cgo_0 [4]byte
+ Data [8]byte // unaligned uintptr
+}
diff --git a/src/runtime/internal/syscall/defs_linux_mipsx.go b/src/runtime/internal/syscall/defs_linux_mipsx.go
new file mode 100644
index 0000000..e28d09c
--- /dev/null
+++ b/src/runtime/internal/syscall/defs_linux_mipsx.go
@@ -0,0 +1,32 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build linux && (mips || mipsle)
+
+package syscall
+
+const (
+ SYS_FCNTL = 4055
+ SYS_EPOLL_CTL = 4249
+ SYS_EPOLL_PWAIT = 4313
+ SYS_EPOLL_CREATE1 = 4326
+ SYS_EPOLL_PWAIT2 = 4441
+
+ EPOLLIN = 0x1
+ EPOLLOUT = 0x4
+ EPOLLERR = 0x8
+ EPOLLHUP = 0x10
+ EPOLLRDHUP = 0x2000
+ EPOLLET = 0x80000000
+ EPOLL_CLOEXEC = 0x80000
+ EPOLL_CTL_ADD = 0x1
+ EPOLL_CTL_DEL = 0x2
+ EPOLL_CTL_MOD = 0x3
+)
+
+type EpollEvent struct {
+ Events uint32
+ pad_cgo_0 [4]byte
+ Data uint64
+}
diff --git a/src/runtime/internal/syscall/defs_linux_ppc64x.go b/src/runtime/internal/syscall/defs_linux_ppc64x.go
new file mode 100644
index 0000000..a74483e
--- /dev/null
+++ b/src/runtime/internal/syscall/defs_linux_ppc64x.go
@@ -0,0 +1,32 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build linux && (ppc64 || ppc64le)
+
+package syscall
+
+const (
+ SYS_FCNTL = 55
+ SYS_EPOLL_CTL = 237
+ SYS_EPOLL_PWAIT = 303
+ SYS_EPOLL_CREATE1 = 315
+ SYS_EPOLL_PWAIT2 = 441
+
+ EPOLLIN = 0x1
+ EPOLLOUT = 0x4
+ EPOLLERR = 0x8
+ EPOLLHUP = 0x10
+ EPOLLRDHUP = 0x2000
+ EPOLLET = 0x80000000
+ EPOLL_CLOEXEC = 0x80000
+ EPOLL_CTL_ADD = 0x1
+ EPOLL_CTL_DEL = 0x2
+ EPOLL_CTL_MOD = 0x3
+)
+
+type EpollEvent struct {
+ Events uint32
+ pad_cgo_0 [4]byte
+ Data [8]byte // unaligned uintptr
+}
diff --git a/src/runtime/internal/syscall/defs_linux_riscv64.go b/src/runtime/internal/syscall/defs_linux_riscv64.go
new file mode 100644
index 0000000..b78ef81
--- /dev/null
+++ b/src/runtime/internal/syscall/defs_linux_riscv64.go
@@ -0,0 +1,30 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package syscall
+
+const (
+ SYS_EPOLL_CREATE1 = 20
+ SYS_EPOLL_CTL = 21
+ SYS_EPOLL_PWAIT = 22
+ SYS_FCNTL = 25
+ SYS_EPOLL_PWAIT2 = 441
+
+ EPOLLIN = 0x1
+ EPOLLOUT = 0x4
+ EPOLLERR = 0x8
+ EPOLLHUP = 0x10
+ EPOLLRDHUP = 0x2000
+ EPOLLET = 0x80000000
+ EPOLL_CLOEXEC = 0x80000
+ EPOLL_CTL_ADD = 0x1
+ EPOLL_CTL_DEL = 0x2
+ EPOLL_CTL_MOD = 0x3
+)
+
+type EpollEvent struct {
+ Events uint32
+ pad_cgo_0 [4]byte
+ Data [8]byte // unaligned uintptr
+}
diff --git a/src/runtime/internal/syscall/defs_linux_s390x.go b/src/runtime/internal/syscall/defs_linux_s390x.go
new file mode 100644
index 0000000..a7bb1ba
--- /dev/null
+++ b/src/runtime/internal/syscall/defs_linux_s390x.go
@@ -0,0 +1,30 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package syscall
+
+const (
+ SYS_FCNTL = 55
+ SYS_EPOLL_CTL = 250
+ SYS_EPOLL_PWAIT = 312
+ SYS_EPOLL_CREATE1 = 327
+ SYS_EPOLL_PWAIT2 = 441
+
+ EPOLLIN = 0x1
+ EPOLLOUT = 0x4
+ EPOLLERR = 0x8
+ EPOLLHUP = 0x10
+ EPOLLRDHUP = 0x2000
+ EPOLLET = 0x80000000
+ EPOLL_CLOEXEC = 0x80000
+ EPOLL_CTL_ADD = 0x1
+ EPOLL_CTL_DEL = 0x2
+ EPOLL_CTL_MOD = 0x3
+)
+
+type EpollEvent struct {
+ Events uint32
+ pad_cgo_0 [4]byte
+ Data [8]byte // unaligned uintptr
+}
diff --git a/src/runtime/internal/syscall/syscall_linux.go b/src/runtime/internal/syscall/syscall_linux.go
new file mode 100644
index 0000000..7209634
--- /dev/null
+++ b/src/runtime/internal/syscall/syscall_linux.go
@@ -0,0 +1,62 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package syscall provides the syscall primitives required for the runtime.
+package syscall
+
+import (
+ "unsafe"
+)
+
+// TODO(https://go.dev/issue/51087): This package is incomplete and currently
+// only contains very minimal support for Linux.
+
+// Syscall6 calls system call number 'num' with arguments a1-6.
+func Syscall6(num, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2, errno uintptr)
+
+// syscall_RawSyscall6 is a push linkname to export Syscall6 as
+// syscall.RawSyscall6.
+//
+// //go:uintptrkeepalive because the uintptr argument may be converted pointers
+// that need to be kept alive in the caller (this is implied for Syscall6 since
+// it has no body).
+//
+// //go:nosplit because stack copying does not account for uintptrkeepalive, so
+// the stack must not grow. Stack copying cannot blindly assume that all
+// uintptr arguments are pointers, because some values may look like pointers,
+// but not really be pointers, and adjusting their value would break the call.
+//
+// This is a separate wrapper because we can't export one function as two
+// names. The assembly implementations name themselves Syscall6 would not be
+// affected by a linkname.
+//
+//go:uintptrkeepalive
+//go:nosplit
+//go:linkname syscall_RawSyscall6 syscall.RawSyscall6
+func syscall_RawSyscall6(num, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2, errno uintptr) {
+ return Syscall6(num, a1, a2, a3, a4, a5, a6)
+}
+
+func EpollCreate1(flags int32) (fd int32, errno uintptr) {
+ r1, _, e := Syscall6(SYS_EPOLL_CREATE1, uintptr(flags), 0, 0, 0, 0, 0)
+ return int32(r1), e
+}
+
+var _zero uintptr
+
+func EpollWait(epfd int32, events []EpollEvent, maxev, waitms int32) (n int32, errno uintptr) {
+ var ev unsafe.Pointer
+ if len(events) > 0 {
+ ev = unsafe.Pointer(&events[0])
+ } else {
+ ev = unsafe.Pointer(&_zero)
+ }
+ r1, _, e := Syscall6(SYS_EPOLL_PWAIT, uintptr(epfd), uintptr(ev), uintptr(maxev), uintptr(waitms), 0, 0)
+ return int32(r1), e
+}
+
+func EpollCtl(epfd, op, fd int32, event *EpollEvent) (errno uintptr) {
+ _, _, e := Syscall6(SYS_EPOLL_CTL, uintptr(epfd), uintptr(op), uintptr(fd), uintptr(unsafe.Pointer(event)), 0, 0)
+ return e
+}
diff --git a/src/runtime/internal/syscall/syscall_linux_test.go b/src/runtime/internal/syscall/syscall_linux_test.go
new file mode 100644
index 0000000..1976da5
--- /dev/null
+++ b/src/runtime/internal/syscall/syscall_linux_test.go
@@ -0,0 +1,19 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package syscall_test
+
+import (
+ "runtime/internal/syscall"
+ "testing"
+)
+
+func TestEpollctlErrorSign(t *testing.T) {
+ v := syscall.EpollCtl(-1, 1, -1, &syscall.EpollEvent{})
+
+ const EBADF = 0x09
+ if v != EBADF {
+ t.Errorf("epollctl = %v, want %v", v, EBADF)
+ }
+}