1 files changed, 41 insertions, 58 deletions
diff --git a/pkg/sentry/kernel/pipe/pipe_util.go b/pkg/sentry/kernel/pipe/pipe_util.go
index f665920cb..77246edbe 100644
--- a/pkg/sentry/kernel/pipe/pipe_util.go
+++ b/pkg/sentry/kernel/pipe/pipe_util.go
@@ -21,9 +21,9 @@ import (
 
 	"gvisor.dev/gvisor/pkg/abi/linux"
 	"gvisor.dev/gvisor/pkg/amutex"
-	"gvisor.dev/gvisor/pkg/buffer"
 	"gvisor.dev/gvisor/pkg/context"
 	"gvisor.dev/gvisor/pkg/marshal/primitive"
+	"gvisor.dev/gvisor/pkg/safemem"
 	"gvisor.dev/gvisor/pkg/sentry/arch"
 	"gvisor.dev/gvisor/pkg/sync"
 	"gvisor.dev/gvisor/pkg/usermem"
@@ -44,46 +44,37 @@ func (p *Pipe) Release(context.Context) {
 
 // Read reads from the Pipe into dst.
 func (p *Pipe) Read(ctx context.Context, dst usermem.IOSequence) (int64, error) {
-	n, err := p.read(ctx, readOps{
-		left: func() int64 {
-			return dst.NumBytes()
-		},
-		limit: func(l int64) {
-			dst = dst.TakeFirst64(l)
-		},
-		read: func(view *buffer.View) (int64, error) {
-			n, err := dst.CopyOutFrom(ctx, view)
-			dst = dst.DropFirst64(n)
-			view.TrimFront(n)
-			return n, err
-		},
-	})
+	n, err := dst.CopyOutFrom(ctx, p)
 	if n > 0 {
 		p.Notify(waiter.EventOut)
 	}
 	return n, err
 }
 
+// ReadToBlocks implements safemem.Reader.ReadToBlocks for Pipe.Read.
+func (p *Pipe) ReadToBlocks(dsts safemem.BlockSeq) (uint64, error) {
+	n, err := p.read(int64(dsts.NumBytes()), func(srcs safemem.BlockSeq) (uint64, error) {
+		return safemem.CopySeq(dsts, srcs)
+	}, true /* removeFromSrc */)
+	return uint64(n), err
+}
+
+func (p *Pipe) read(count int64, f func(srcs safemem.BlockSeq) (uint64, error), removeFromSrc bool) (int64, error) {
+	p.mu.Lock()
+	defer p.mu.Unlock()
+	n, err := p.peekLocked(count, f)
+	if n > 0 && removeFromSrc {
+		p.consumeLocked(n)
+	}
+	return n, err
+}
+
 // WriteTo writes to w from the Pipe.
 func (p *Pipe) WriteTo(ctx context.Context, w io.Writer, count int64, dup bool) (int64, error) {
-	ops := readOps{
-		left: func() int64 {
-			return count
-		},
-		limit: func(l int64) {
-			count = l
-		},
-		read: func(view *buffer.View) (int64, error) {
-			n, err := view.ReadToWriter(w, count)
-			if !dup {
-				view.TrimFront(n)
-			}
-			count -= n
-			return n, err
-		},
-	}
-	n, err := p.read(ctx, ops)
-	if n > 0 {
+	n, err := p.read(count, func(srcs safemem.BlockSeq) (uint64, error) {
+		return safemem.FromIOWriter{w}.WriteFromBlocks(srcs)
+	}, !dup /* removeFromSrc */)
+	if n > 0 && !dup {
 		p.Notify(waiter.EventOut)
 	}
 	return n, err
@@ -91,39 +82,31 @@ func (p *Pipe) WriteTo(ctx context.Context, w io.Writer, count int64, dup bool)
 
 // Write writes to the Pipe from src.
 func (p *Pipe) Write(ctx context.Context, src usermem.IOSequence) (int64, error) {
-	n, err := p.write(ctx, writeOps{
-		left: func() int64 {
-			return src.NumBytes()
-		},
-		limit: func(l int64) {
-			src = src.TakeFirst64(l)
-		},
-		write: func(view *buffer.View) (int64, error) {
-			n, err := src.CopyInTo(ctx, view)
-			src = src.DropFirst64(n)
-			return n, err
-		},
-	})
+	n, err := src.CopyInTo(ctx, p)
 	if n > 0 {
 		p.Notify(waiter.EventIn)
 	}
 	return n, err
 }
 
+// WriteFromBlocks implements safemem.Writer.WriteFromBlocks for Pipe.Write.
+func (p *Pipe) WriteFromBlocks(srcs safemem.BlockSeq) (uint64, error) {
+	n, err := p.write(int64(srcs.NumBytes()), func(dsts safemem.BlockSeq) (uint64, error) {
+		return safemem.CopySeq(dsts, srcs)
+	})
+	return uint64(n), err
+}
+
+func (p *Pipe) write(count int64, f func(safemem.BlockSeq) (uint64, error)) (int64, error) {
+	p.mu.Lock()
+	defer p.mu.Unlock()
+	return p.writeLocked(count, f)
+}
+
 // ReadFrom reads from r to the Pipe.
 func (p *Pipe) ReadFrom(ctx context.Context, r io.Reader, count int64) (int64, error) {
-	n, err := p.write(ctx, writeOps{
-		left: func() int64 {
-			return count
-		},
-		limit: func(l int64) {
-			count = l
-		},
-		write: func(view *buffer.View) (int64, error) {
-			n, err := view.WriteFromReader(r, count)
-			count -= n
-			return n, err
-		},
+	n, err := p.write(count, func(dsts safemem.BlockSeq) (uint64, error) {
+		return safemem.FromIOReader{r}.ReadToBlocks(dsts)
 	})
 	if n > 0 {
 		p.Notify(waiter.EventIn)