[op] Replace syscall package usage with golang.org/x/sys/unix in pkg/.

The syscall package has been deprecated in favor of golang.org/x/sys.

Note that syscall is still used in the following places:
- pkg/sentry/socket/hostinet/stack.go: some netlink related functionalities
  are not yet available in golang.org/x/sys.
- syscall.Stat_t is still used in some places because os.FileInfo.Sys() still
  returns it and not unix.Stat_t.

Updates #214

PiperOrigin-RevId: 360701387

3 files changed, 10 insertions, 10 deletions

diff --git a/pkg/usermem/BUILD b/pkg/usermem/BUILD
index 6c9ada9c7..054269b59 100644
--- a/pkg/usermem/BUILD
+++ b/pkg/usermem/BUILD
@@ -36,6 +36,7 @@ go_library(
         "//pkg/log",
         "//pkg/safemem",
         "//pkg/syserror",
+        "@org_golang_x_sys//unix:go_default_library",
     ],
 )
 
diff --git a/pkg/usermem/access_type.go b/pkg/usermem/access_type.go
index 9c1742a59..2cfca29af 100644
--- a/pkg/usermem/access_type.go
+++ b/pkg/usermem/access_type.go
@@ -14,9 +14,7 @@
 
 package usermem
 
-import (
-	"syscall"
-)
+import "golang.org/x/sys/unix"
 
 // AccessType specifies memory access types. This is used for
 // setting mapping permissions, as well as communicating faults.
@@ -54,17 +52,17 @@ func (a AccessType) Any() bool {
 	return a.Read || a.Write || a.Execute
 }
 
-// Prot returns the system prot (syscall.PROT_READ, etc.) for this access.
+// Prot returns the system prot (unix.PROT_READ, etc.) for this access.
 func (a AccessType) Prot() int {
 	var prot int
 	if a.Read {
-		prot |= syscall.PROT_READ
+		prot |= unix.PROT_READ
 	}
 	if a.Write {
-		prot |= syscall.PROT_WRITE
+		prot |= unix.PROT_WRITE
 	}
 	if a.Execute {
-		prot |= syscall.PROT_EXEC
+		prot |= unix.PROT_EXEC
 	}
 	return prot
 }
diff --git a/pkg/usermem/usermem_arm64.go b/pkg/usermem/usermem_arm64.go
index fdfc30a66..7e7529585 100644
--- a/pkg/usermem/usermem_arm64.go
+++ b/pkg/usermem/usermem_arm64.go
@@ -18,13 +18,14 @@ package usermem
 
 import (
 	"encoding/binary"
-	"syscall"
+
+	"golang.org/x/sys/unix"
 )
 
 const (
 	// PageSize is the system page size.
 	// arm64 support 4K/16K/64K page size,
-	// which can be get by syscall.Getpagesize().
+	// which can be get by unix.Getpagesize().
 	// Currently, only 4K page size is supported.
 	PageSize = 1 << PageShift
 
@@ -47,7 +48,7 @@ var (
 
 func init() {
 	// Make sure the page size is 4K on arm64 platform.
-	if size := syscall.Getpagesize(); size != PageSize {
+	if size := unix.Getpagesize(); size != PageSize {
 		panic("Only 4K page size is supported on arm64!")
 	}
 }