Update package locations.

Because the abi will depend on the core types for marshalling (usermem,
context, safemem, safecopy), these need to be flattened from the sentry
directory. These packages contain no sentry-specific details.

PiperOrigin-RevId: 291811289

1 files changed, 136 insertions, 0 deletions

diff --git a/pkg/safecopy/atomic_amd64.s b/pkg/safecopy/atomic_amd64.s
new file mode 100644
index 000000000..a0cd78f33
--- /dev/null
+++ b/pkg/safecopy/atomic_amd64.s
@@ -0,0 +1,136 @@
+// Copyright 2018 The gVisor Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "textflag.h"
+
+// handleSwapUint32Fault returns the value stored in DI. Control is transferred
+// to it when swapUint32 below receives SIGSEGV or SIGBUS, with the signal
+// number stored in DI.
+//
+// It must have the same frame configuration as swapUint32 so that it can undo
+// any potential call frame set up by the assembler.
+TEXT handleSwapUint32Fault(SB), NOSPLIT, $0-24
+  MOVL DI, sig+20(FP)
+  RET
+
+// swapUint32 atomically stores new into *addr and returns (the previous *addr
+// value, 0). If a SIGSEGV or SIGBUS signal is received during the swap, the
+// value of old is unspecified, and sig is the number of the signal that was
+// received.
+//
+// Preconditions: addr must be aligned to a 4-byte boundary.
+//
+//func swapUint32(ptr unsafe.Pointer, new uint32) (old uint32, sig int32)
+TEXT ·swapUint32(SB), NOSPLIT, $0-24
+  // Store 0 as the returned signal number. If we run to completion,
+  // this is the value the caller will see; if a signal is received,
+  // handleSwapUint32Fault will store a different value in this address.
+  MOVL $0, sig+20(FP)
+
+  MOVQ addr+0(FP), DI
+  MOVL new+8(FP), AX
+  XCHGL AX, 0(DI)
+  MOVL AX, old+16(FP)
+  RET
+
+// handleSwapUint64Fault returns the value stored in DI. Control is transferred
+// to it when swapUint64 below receives SIGSEGV or SIGBUS, with the signal
+// number stored in DI.
+//
+// It must have the same frame configuration as swapUint64 so that it can undo
+// any potential call frame set up by the assembler.
+TEXT handleSwapUint64Fault(SB), NOSPLIT, $0-28
+  MOVL DI, sig+24(FP)
+  RET
+
+// swapUint64 atomically stores new into *addr and returns (the previous *addr
+// value, 0). If a SIGSEGV or SIGBUS signal is received during the swap, the
+// value of old is unspecified, and sig is the number of the signal that was
+// received.
+//
+// Preconditions: addr must be aligned to a 8-byte boundary.
+//
+//func swapUint64(ptr unsafe.Pointer, new uint64) (old uint64, sig int32)
+TEXT ·swapUint64(SB), NOSPLIT, $0-28
+  // Store 0 as the returned signal number. If we run to completion,
+  // this is the value the caller will see; if a signal is received,
+  // handleSwapUint64Fault will store a different value in this address.
+  MOVL $0, sig+24(FP)
+
+  MOVQ addr+0(FP), DI
+  MOVQ new+8(FP), AX
+  XCHGQ AX, 0(DI)
+  MOVQ AX, old+16(FP)
+  RET
+
+// handleCompareAndSwapUint32Fault returns the value stored in DI. Control is
+// transferred to it when swapUint64 below receives SIGSEGV or SIGBUS, with the
+// signal number stored in DI.
+//
+// It must have the same frame configuration as compareAndSwapUint32 so that it
+// can undo any potential call frame set up by the assembler.
+TEXT handleCompareAndSwapUint32Fault(SB), NOSPLIT, $0-24
+  MOVL DI, sig+20(FP)
+  RET
+
+// compareAndSwapUint32 is like sync/atomic.CompareAndSwapUint32, but returns
+// (the value previously stored at addr, 0). If a SIGSEGV or SIGBUS signal is
+// received during the operation, the value of prev is unspecified, and sig is
+// the number of the signal that was received.
+//
+// Preconditions: addr must be aligned to a 4-byte boundary.
+//
+//func compareAndSwapUint32(ptr unsafe.Pointer, old, new uint32) (prev uint32, sig int32)
+TEXT ·compareAndSwapUint32(SB), NOSPLIT, $0-24
+  // Store 0 as the returned signal number. If we run to completion, this is
+  // the value the caller will see; if a signal is received,
+  // handleCompareAndSwapUint32Fault will store a different value in this
+  // address.
+  MOVL $0, sig+20(FP)
+
+  MOVQ addr+0(FP), DI
+  MOVL old+8(FP), AX
+  MOVL new+12(FP), DX
+  LOCK
+  CMPXCHGL DX, 0(DI)
+  MOVL AX, prev+16(FP)
+  RET
+
+// handleLoadUint32Fault returns the value stored in DI. Control is transferred
+// to it when LoadUint32 below receives SIGSEGV or SIGBUS, with the signal
+// number stored in DI.
+//
+// It must have the same frame configuration as loadUint32 so that it can undo
+// any potential call frame set up by the assembler.
+TEXT handleLoadUint32Fault(SB), NOSPLIT, $0-16
+  MOVL DI, sig+12(FP)
+  RET
+
+// loadUint32 atomically loads *addr and returns it. If a SIGSEGV or SIGBUS
+// signal is received, the value returned is unspecified, and sig is the number
+// of the signal that was received.
+//
+// Preconditions: addr must be aligned to a 4-byte boundary.
+//
+//func loadUint32(ptr unsafe.Pointer) (val uint32, sig int32)
+TEXT ·loadUint32(SB), NOSPLIT, $0-16
+  // Store 0 as the returned signal number. If we run to completion,
+  // this is the value the caller will see; if a signal is received,
+  // handleLoadUint32Fault will store a different value in this address.
+  MOVL $0, sig+12(FP)
+
+  MOVQ addr+0(FP), AX
+  MOVL (AX), BX
+  MOVL BX, val+8(FP)
+  RET