Decouple filemem from platform and move it to pgalloc.MemoryFile.

This is in preparation for improved page cache reclaim, which requires
greater integration between the page cache and page allocator.

PiperOrigin-RevId: 238444706
Change-Id: Id24141b3678d96c7d7dc24baddd9be555bffafe4

1 files changed, 1 insertions, 13 deletions

diff --git a/pkg/sentry/platform/ptrace/ptrace.go b/pkg/sentry/platform/ptrace/ptrace.go
index 8d3f6ac9a..3c0713e95 100644
--- a/pkg/sentry/platform/ptrace/ptrace.go
+++ b/pkg/sentry/platform/ptrace/ptrace.go
@@ -50,7 +50,6 @@ import (
 	"gvisor.googlesource.com/gvisor/pkg/abi/linux"
 	"gvisor.googlesource.com/gvisor/pkg/sentry/arch"
 	"gvisor.googlesource.com/gvisor/pkg/sentry/platform"
-	"gvisor.googlesource.com/gvisor/pkg/sentry/platform/filemem"
 	"gvisor.googlesource.com/gvisor/pkg/sentry/platform/interrupt"
 	"gvisor.googlesource.com/gvisor/pkg/sentry/usermem"
 )
@@ -181,7 +180,6 @@ func (c *context) Interrupt() {
 type PTrace struct {
 	platform.MMapMinAddr
 	platform.NoCPUPreemptionDetection
-	*filemem.FileMem
 }
 
 // New returns a new ptrace-based implementation of the platform interface.
@@ -202,12 +200,7 @@ func New() (*PTrace, error) {
 		globalPool.master = master
 	})
 
-	fm, err := filemem.New("ptrace-memory")
-	if err != nil {
-		return nil, err
-	}
-
-	return &PTrace{FileMem: fm}, nil
+	return &PTrace{}, nil
 }
 
 // SupportsAddressSpaceIO implements platform.Platform.SupportsAddressSpaceIO.
@@ -243,8 +236,3 @@ func (p *PTrace) NewAddressSpace(_ interface{}) (platform.AddressSpace, <-chan s
 func (*PTrace) NewContext() platform.Context {
 	return &context{}
 }
-
-// Memory returns the platform memory used to do allocations.
-func (p *PTrace) Memory() platform.Memory {
-	return p.FileMem
-}