1 files changed, 42 insertions, 0 deletions
diff --git a/pkg/sentry/syscalls/linux/sys_sysinfo.go b/pkg/sentry/syscalls/linux/sys_sysinfo.go
new file mode 100644
index 000000000..bd0ffcd5c
--- /dev/null
+++ b/pkg/sentry/syscalls/linux/sys_sysinfo.go
@@ -0,0 +1,42 @@
+// Copyright 2018 Google Inc.
+//
+// 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.googlesource.com/gvisor/pkg/abi/linux"
+	"gvisor.googlesource.com/gvisor/pkg/sentry/arch"
+	"gvisor.googlesource.com/gvisor/pkg/sentry/kernel"
+	"gvisor.googlesource.com/gvisor/pkg/sentry/usage"
+)
+
+// Sysinfo implements the sysinfo syscall as described in man 2 sysinfo.
+func Sysinfo(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) {
+	addr := args[0].Pointer()
+
+	mem := t.Kernel().Platform.Memory()
+	mem.UpdateUsage()
+	_, totalUsage := usage.MemoryAccounting.Copy()
+	totalSize := usage.TotalMemory(mem.TotalSize(), totalUsage)
+
+	// Only a subset of the fields in sysinfo_t make sense to return.
+	si := linux.Sysinfo{
+		Procs:    uint16(len(t.PIDNamespace().Tasks())),
+		Uptime:   t.Kernel().MonotonicClock().Now().Seconds(),
+		TotalRAM: totalSize,
+		FreeRAM:  totalSize - totalUsage,
+	}
+	_, err := t.CopyOut(addr, si)
+	return 0, nil, err
+}