Implement sysv shm.

PiperOrigin-RevId: 197058289
Change-Id: I3946c25028b7e032be4894d61acb48ac0c24d574

2 files changed, 76 insertions, 0 deletions

diff --git a/pkg/abi/linux/BUILD b/pkg/abi/linux/BUILD
index a428e61a3..693ce0fdd 100644
--- a/pkg/abi/linux/BUILD
+++ b/pkg/abi/linux/BUILD
@@ -51,6 +51,7 @@ go_library(
         "sched.go",
         "seccomp.go",
         "sem.go",
+        "shm.go",
         "signal.go",
         "socket.go",
         "time.go",
diff --git a/pkg/abi/linux/shm.go b/pkg/abi/linux/shm.go
new file mode 100644
index 000000000..9149ed094
--- /dev/null
+++ b/pkg/abi/linux/shm.go
@@ -0,0 +1,75 @@
+// 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
+
+// shmat(2) flags. Source: include/uapi/linux/shm.h
+const (
+	SHM_RDONLY = 010000  // Read-only access.
+	SHM_RND    = 020000  // Round attach address to SHMLBA boundary.
+	SHM_REMAP  = 040000  // Take-over region on attach.
+	SHM_EXEC   = 0100000 // Execution access.
+)
+
+// IPCPerm.Mode upper byte flags. Source: include/linux/shm.h
+const (
+	SHM_DEST      = 01000  // Segment will be destroyed on last detach.
+	SHM_LOCKED    = 02000  // Segment will not be swapped.
+	SHM_HUGETLB   = 04000  // Segment will use huge TLB pages.
+	SHM_NORESERVE = 010000 // Don't check for reservations.
+)
+
+// Additional Linux-only flags for shmctl(2). Source: include/uapi/linux/shm.h
+const (
+	SHM_LOCK   = 11
+	SHM_UNLOCK = 12
+	SHM_STAT   = 13
+	SHM_INFO   = 14
+)
+
+// ShmidDS is equivalent to struct shmid64_ds. Source:
+// include/uapi/asm-generic/shmbuf.h
+type ShmidDS struct {
+	ShmPerm    IPCPerm
+	ShmSegsz   uint64
+	ShmAtime   TimeT
+	ShmDtime   TimeT
+	ShmCtime   TimeT
+	ShmCpid    int32
+	ShmLpid    int32
+	ShmNattach uint64
+
+	Unused4 uint64
+	Unused5 uint64
+}
+
+// ShmParams is equivalent to struct shminfo. Source: include/uapi/linux/shm.h
+type ShmParams struct {
+	ShmMax uint64
+	ShmMin uint64
+	ShmMni uint64
+	ShmSeg uint64
+	ShmAll uint64
+}
+
+// ShmInfo is equivalent to struct shm_info. Source: include/uapi/linux/shm.h
+type ShmInfo struct {
+	UsedIDs       int32 // Number of currently existing segments.
+	_             [4]byte
+	ShmTot        uint64 // Total number of shared memory pages.
+	ShmRss        uint64 // Number of resident shared memory pages.
+	ShmSwp        uint64 // Number of swapped shared memory pages.
+	SwapAttempts  uint64 // Unused since Linux 2.4.
+	SwapSuccesses uint64 // Unused since Linux 2.4.
+}