Enable automated marshalling for mempolicy syscalls.

PiperOrigin-RevId: 308170679

6 files changed, 27 insertions, 21 deletions

diff --git a/pkg/abi/linux/mm.go b/pkg/abi/linux/mm.go
index cd043dac3..07cc1895e 100644
--- a/pkg/abi/linux/mm.go
+++ b/pkg/abi/linux/mm.go
@@ -90,14 +90,19 @@ const (
 	MS_SYNC       = 1 << 2
 )
 
+// NumaPolicy is the NUMA memory policy for a memory range. See numa(7).
+//
+// +marshal
+type NumaPolicy int32
+
 // Policies for get_mempolicy(2)/set_mempolicy(2).
 const (
-	MPOL_DEFAULT    = 0
-	MPOL_PREFERRED  = 1
-	MPOL_BIND       = 2
-	MPOL_INTERLEAVE = 3
-	MPOL_LOCAL      = 4
-	MPOL_MAX        = 5
+	MPOL_DEFAULT    NumaPolicy = 0
+	MPOL_PREFERRED  NumaPolicy = 1
+	MPOL_BIND       NumaPolicy = 2
+	MPOL_INTERLEAVE NumaPolicy = 3
+	MPOL_LOCAL      NumaPolicy = 4
+	MPOL_MAX        NumaPolicy = 5
 )
 
 // Flags for get_mempolicy(2).
diff --git a/pkg/sentry/kernel/task.go b/pkg/sentry/kernel/task.go
index e5d133d6c..f48247c94 100644
--- a/pkg/sentry/kernel/task.go
+++ b/pkg/sentry/kernel/task.go
@@ -484,7 +484,7 @@ type Task struct {
 	// bit.
 	//
 	// numaPolicy and numaNodeMask are protected by mu.
-	numaPolicy   int32
+	numaPolicy   linux.NumaPolicy
 	numaNodeMask uint64
 
 	// netns is the task's network namespace. netns is never nil.
diff --git a/pkg/sentry/kernel/task_sched.go b/pkg/sentry/kernel/task_sched.go
index 8b148db35..09366b60c 100644
--- a/pkg/sentry/kernel/task_sched.go
+++ b/pkg/sentry/kernel/task_sched.go
@@ -653,14 +653,14 @@ func (t *Task) SetNiceness(n int) {
 }
 
 // NumaPolicy returns t's current numa policy.
-func (t *Task) NumaPolicy() (policy int32, nodeMask uint64) {
+func (t *Task) NumaPolicy() (policy linux.NumaPolicy, nodeMask uint64) {
 	t.mu.Lock()
 	defer t.mu.Unlock()
 	return t.numaPolicy, t.numaNodeMask
 }
 
 // SetNumaPolicy sets t's numa policy.
-func (t *Task) SetNumaPolicy(policy int32, nodeMask uint64) {
+func (t *Task) SetNumaPolicy(policy linux.NumaPolicy, nodeMask uint64) {
 	t.mu.Lock()
 	defer t.mu.Unlock()
 	t.numaPolicy = policy
diff --git a/pkg/sentry/mm/mm.go b/pkg/sentry/mm/mm.go
index 34d3bde7a..6db7c3d40 100644
--- a/pkg/sentry/mm/mm.go
+++ b/pkg/sentry/mm/mm.go
@@ -35,6 +35,7 @@
 package mm
 
 import (
+	"gvisor.dev/gvisor/pkg/abi/linux"
 	"gvisor.dev/gvisor/pkg/safemem"
 	"gvisor.dev/gvisor/pkg/sentry/arch"
 	"gvisor.dev/gvisor/pkg/sentry/fsbridge"
@@ -286,7 +287,7 @@ type vma struct {
 	mlockMode memmap.MLockMode
 
 	// numaPolicy is the NUMA policy for this vma set by mbind().
-	numaPolicy int32
+	numaPolicy linux.NumaPolicy
 
 	// numaNodemask is the NUMA nodemask for this vma set by mbind().
 	numaNodemask uint64
diff --git a/pkg/sentry/mm/syscalls.go b/pkg/sentry/mm/syscalls.go
index c5dfa5972..3f496aa9f 100644
--- a/pkg/sentry/mm/syscalls.go
+++ b/pkg/sentry/mm/syscalls.go
@@ -974,7 +974,7 @@ func (mm *MemoryManager) MLockAll(ctx context.Context, opts MLockAllOpts) error
 }
 
 // NumaPolicy implements the semantics of Linux's get_mempolicy(MPOL_F_ADDR).
-func (mm *MemoryManager) NumaPolicy(addr usermem.Addr) (int32, uint64, error) {
+func (mm *MemoryManager) NumaPolicy(addr usermem.Addr) (linux.NumaPolicy, uint64, error) {
 	mm.mappingMu.RLock()
 	defer mm.mappingMu.RUnlock()
 	vseg := mm.vmas.FindSegment(addr)
@@ -986,7 +986,7 @@ func (mm *MemoryManager) NumaPolicy(addr usermem.Addr) (int32, uint64, error) {
 }
 
 // SetNumaPolicy implements the semantics of Linux's mbind().
-func (mm *MemoryManager) SetNumaPolicy(addr usermem.Addr, length uint64, policy int32, nodemask uint64) error {
+func (mm *MemoryManager) SetNumaPolicy(addr usermem.Addr, length uint64, policy linux.NumaPolicy, nodemask uint64) error {
 	if !addr.IsPageAligned() {
 		return syserror.EINVAL
 	}
diff --git a/pkg/sentry/syscalls/linux/sys_mempolicy.go b/pkg/sentry/syscalls/linux/sys_mempolicy.go
index ac934dc6f..9b4a5c3f1 100644
--- a/pkg/sentry/syscalls/linux/sys_mempolicy.go
+++ b/pkg/sentry/syscalls/linux/sys_mempolicy.go
@@ -162,10 +162,10 @@ func GetMempolicy(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.
 			if err != nil {
 				return 0, nil, err
 			}
-			policy = 0 // maxNodes == 1
+			policy = linux.MPOL_DEFAULT // maxNodes == 1
 		}
 		if mode != 0 {
-			if _, err := t.CopyOut(mode, policy); err != nil {
+			if _, err := policy.CopyOut(t, mode); err != nil {
 				return 0, nil, err
 			}
 		}
@@ -199,10 +199,10 @@ func GetMempolicy(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.
 		if policy&^linux.MPOL_MODE_FLAGS != linux.MPOL_INTERLEAVE {
 			return 0, nil, syserror.EINVAL
 		}
-		policy = 0 // maxNodes == 1
+		policy = linux.MPOL_DEFAULT // maxNodes == 1
 	}
 	if mode != 0 {
-		if _, err := t.CopyOut(mode, policy); err != nil {
+		if _, err := policy.CopyOut(t, mode); err != nil {
 			return 0, nil, err
 		}
 	}
@@ -216,7 +216,7 @@ func GetMempolicy(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.
 
 // SetMempolicy implements the syscall set_mempolicy(2).
 func SetMempolicy(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) {
-	modeWithFlags := args[0].Int()
+	modeWithFlags := linux.NumaPolicy(args[0].Int())
 	nodemask := args[1].Pointer()
 	maxnode := args[2].Uint()
 
@@ -233,7 +233,7 @@ func SetMempolicy(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.
 func Mbind(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) {
 	addr := args[0].Pointer()
 	length := args[1].Uint64()
-	mode := args[2].Int()
+	mode := linux.NumaPolicy(args[2].Int())
 	nodemask := args[3].Pointer()
 	maxnode := args[4].Uint()
 	flags := args[5].Uint()
@@ -258,9 +258,9 @@ func Mbind(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscall
 	return 0, nil, err
 }
 
-func copyInMempolicyNodemask(t *kernel.Task, modeWithFlags int32, nodemask usermem.Addr, maxnode uint32) (int32, uint64, error) {
-	flags := modeWithFlags & linux.MPOL_MODE_FLAGS
-	mode := modeWithFlags &^ linux.MPOL_MODE_FLAGS
+func copyInMempolicyNodemask(t *kernel.Task, modeWithFlags linux.NumaPolicy, nodemask usermem.Addr, maxnode uint32) (linux.NumaPolicy, uint64, error) {
+	flags := linux.NumaPolicy(modeWithFlags & linux.MPOL_MODE_FLAGS)
+	mode := linux.NumaPolicy(modeWithFlags &^ linux.MPOL_MODE_FLAGS)
 	if flags == linux.MPOL_MODE_FLAGS {
 		// Can't specify both mode flags simultaneously.
 		return 0, 0, syserror.EINVAL