Port most syscalls to VFS2.

pipe and pipe2 aren't ported, pending a slight rework of pipe FDs for VFS2.
mount and umount2 aren't ported out of temporary laziness. access and faccessat
need additional FSImpl methods to implement properly, but are stubbed to
prevent googletest from CHECK-failing. Other syscalls require additional
plumbing.

Updates #1623

PiperOrigin-RevId: 297188448

1 files changed, 2 insertions, 10 deletions

diff --git a/pkg/sentry/vfs/mount_unsafe.go b/pkg/sentry/vfs/mount_unsafe.go
index 1fe766a44..bc7581698 100644
--- a/pkg/sentry/vfs/mount_unsafe.go
+++ b/pkg/sentry/vfs/mount_unsafe.go
@@ -26,6 +26,7 @@ import (
 	"sync/atomic"
 	"unsafe"
 
+	"gvisor.dev/gvisor/pkg/gohacks"
 	"gvisor.dev/gvisor/pkg/sync"
 )
 
@@ -160,7 +161,7 @@ func newMountTableSlots(cap uintptr) unsafe.Pointer {
 // Lookup may be called even if there are concurrent mutators of mt.
 func (mt *mountTable) Lookup(parent *Mount, point *Dentry) *Mount {
 	key := mountKey{parent: unsafe.Pointer(parent), point: unsafe.Pointer(point)}
-	hash := memhash(noescape(unsafe.Pointer(&key)), uintptr(mt.seed), mountKeyBytes)
+	hash := memhash(gohacks.Noescape(unsafe.Pointer(&key)), uintptr(mt.seed), mountKeyBytes)
 
 loop:
 	for {
@@ -361,12 +362,3 @@ func memhash(p unsafe.Pointer, seed, s uintptr) uintptr
 
 //go:linkname rand32 runtime.fastrand
 func rand32() uint32
-
-// This is copy/pasted from runtime.noescape(), and is needed because arguments
-// apparently escape from all functions defined by linkname.
-//
-//go:nosplit
-func noescape(p unsafe.Pointer) unsafe.Pointer {
-	x := uintptr(p)
-	return unsafe.Pointer(x ^ 0)
-}