diff options
Diffstat (limited to 'pkg/sentry/syscalls/linux')
| -rw-r--r-- | pkg/sentry/syscalls/linux/BUILD | 1 | ||||
| -rw-r--r-- | pkg/sentry/syscalls/linux/linux64.go | 4 | ||||
| -rw-r--r-- | pkg/sentry/syscalls/linux/sys_membarrier.go | 70 |
3 files changed, 73 insertions, 2 deletions
diff --git a/pkg/sentry/syscalls/linux/BUILD b/pkg/sentry/syscalls/linux/BUILD index 75752b2e6..a2e441448 100644 --- a/pkg/sentry/syscalls/linux/BUILD +++ b/pkg/sentry/syscalls/linux/BUILD @@ -21,6 +21,7 @@ go_library( "sys_identity.go", "sys_inotify.go", "sys_lseek.go", + "sys_membarrier.go", "sys_mempolicy.go", "sys_mmap.go", "sys_mount.go", diff --git a/pkg/sentry/syscalls/linux/linux64.go b/pkg/sentry/syscalls/linux/linux64.go index b293669de..9c9def7cd 100644 --- a/pkg/sentry/syscalls/linux/linux64.go +++ b/pkg/sentry/syscalls/linux/linux64.go @@ -376,7 +376,7 @@ var AMD64 = &kernel.SyscallTable{ 321: syscalls.CapError("bpf", linux.CAP_SYS_ADMIN, "", nil), 322: syscalls.Supported("execveat", Execveat), 323: syscalls.ErrorWithEvent("userfaultfd", syserror.ENOSYS, "", []string{"gvisor.dev/issue/266"}), // TODO(b/118906345) - 324: syscalls.ErrorWithEvent("membarrier", syserror.ENOSYS, "", []string{"gvisor.dev/issue/267"}), // TODO(gvisor.dev/issue/267) + 324: syscalls.PartiallySupported("membarrier", Membarrier, "Not supported on all platforms.", nil), 325: syscalls.PartiallySupported("mlock2", Mlock2, "Stub implementation. The sandbox lacks appropriate permissions.", nil), // Syscalls implemented after 325 are "backports" from versions @@ -695,7 +695,7 @@ var ARM64 = &kernel.SyscallTable{ 280: syscalls.CapError("bpf", linux.CAP_SYS_ADMIN, "", nil), 281: syscalls.Supported("execveat", Execveat), 282: syscalls.ErrorWithEvent("userfaultfd", syserror.ENOSYS, "", []string{"gvisor.dev/issue/266"}), // TODO(b/118906345) - 283: syscalls.ErrorWithEvent("membarrier", syserror.ENOSYS, "", []string{"gvisor.dev/issue/267"}), // TODO(gvisor.dev/issue/267) + 283: syscalls.PartiallySupported("membarrier", Membarrier, "Not supported on all platforms.", nil), 284: syscalls.PartiallySupported("mlock2", Mlock2, "Stub implementation. The sandbox lacks appropriate permissions.", nil), // Syscalls after 284 are "backports" from versions of Linux after 4.4. diff --git a/pkg/sentry/syscalls/linux/sys_membarrier.go b/pkg/sentry/syscalls/linux/sys_membarrier.go new file mode 100644 index 000000000..288cd8512 --- /dev/null +++ b/pkg/sentry/syscalls/linux/sys_membarrier.go @@ -0,0 +1,70 @@ +// Copyright 2020 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. + +package linux + +import ( + "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/sentry/arch" + "gvisor.dev/gvisor/pkg/sentry/kernel" + "gvisor.dev/gvisor/pkg/syserror" +) + +// Membarrier implements syscall membarrier(2). +func Membarrier(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + cmd := args[0].Int() + flags := args[1].Int() + + p := t.Kernel().Platform + if !p.HaveGlobalMemoryBarrier() { + // Event for applications that want membarrier on a configuration that + // doesn't support them. + t.Kernel().EmitUnimplementedEvent(t) + return 0, nil, syserror.ENOSYS + } + + if flags != 0 { + return 0, nil, syserror.EINVAL + } + + switch cmd { + case linux.MEMBARRIER_CMD_QUERY: + const supportedCommands = linux.MEMBARRIER_CMD_GLOBAL | + linux.MEMBARRIER_CMD_GLOBAL_EXPEDITED | + linux.MEMBARRIER_CMD_REGISTER_GLOBAL_EXPEDITED | + linux.MEMBARRIER_CMD_PRIVATE_EXPEDITED | + linux.MEMBARRIER_CMD_REGISTER_PRIVATE_EXPEDITED + return supportedCommands, nil, nil + case linux.MEMBARRIER_CMD_PRIVATE_EXPEDITED: + if !t.MemoryManager().IsMembarrierPrivateEnabled() { + return 0, nil, syserror.EPERM + } + fallthrough + case linux.MEMBARRIER_CMD_GLOBAL, linux.MEMBARRIER_CMD_GLOBAL_EXPEDITED: + return 0, nil, p.GlobalMemoryBarrier() + case linux.MEMBARRIER_CMD_REGISTER_GLOBAL_EXPEDITED: + // no-op + return 0, nil, nil + case linux.MEMBARRIER_CMD_REGISTER_PRIVATE_EXPEDITED: + t.MemoryManager().EnableMembarrierPrivate() + return 0, nil, nil + case linux.MEMBARRIER_CMD_PRIVATE_EXPEDITED_SYNC_CORE, linux.MEMBARRIER_CMD_REGISTER_PRIVATE_EXPEDITED_SYNC_CORE: + // We're aware of these, but they aren't implemented since no platform + // supports them yet. + t.Kernel().EmitUnimplementedEvent(t) + fallthrough + default: + return 0, nil, syserror.EINVAL + } +} |