From 37a217aca4a128d66a6dd4969375ea81bd879ac7 Mon Sep 17 00:00:00 2001
From: Fabricio Voznika <fvoznika@google.com>
Date: Tue, 1 Sep 2020 19:20:37 -0700
Subject: Implement setattr+clunk in 9P

This is to cover the common pattern: open->read/write->close,
where SetAttr needs to be called to update atime/mtime before
the file is closed.

Benchmark results:

BM_OpenReadClose/10240 CPU
setattr+clunk: 63783 ns
VFS2:          68109 ns
VFS1:          72507 ns

Updates #1198

PiperOrigin-RevId: 329628461
---
 pkg/p9/messages.go | 60 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 60 insertions(+)

(limited to 'pkg/p9/messages.go')

diff --git a/pkg/p9/messages.go b/pkg/p9/messages.go
index 2cb59f934..cf13cbb69 100644
--- a/pkg/p9/messages.go
+++ b/pkg/p9/messages.go
@@ -317,6 +317,64 @@ func (r *Rclunk) String() string {
 	return "Rclunk{}"
 }
 
+// Tsetattrclunk is a setattr+close request.
+type Tsetattrclunk struct {
+	// FID is the FID to change.
+	FID FID
+
+	// Valid is the set of bits which will be used.
+	Valid SetAttrMask
+
+	// SetAttr is the set request.
+	SetAttr SetAttr
+}
+
+// decode implements encoder.decode.
+func (t *Tsetattrclunk) decode(b *buffer) {
+	t.FID = b.ReadFID()
+	t.Valid.decode(b)
+	t.SetAttr.decode(b)
+}
+
+// encode implements encoder.encode.
+func (t *Tsetattrclunk) encode(b *buffer) {
+	b.WriteFID(t.FID)
+	t.Valid.encode(b)
+	t.SetAttr.encode(b)
+}
+
+// Type implements message.Type.
+func (*Tsetattrclunk) Type() MsgType {
+	return MsgTsetattrclunk
+}
+
+// String implements fmt.Stringer.
+func (t *Tsetattrclunk) String() string {
+	return fmt.Sprintf("Tsetattrclunk{FID: %d, Valid: %v, SetAttr: %s}", t.FID, t.Valid, t.SetAttr)
+}
+
+// Rsetattrclunk is a setattr+close response.
+type Rsetattrclunk struct {
+}
+
+// decode implements encoder.decode.
+func (*Rsetattrclunk) decode(*buffer) {
+}
+
+// encode implements encoder.encode.
+func (*Rsetattrclunk) encode(*buffer) {
+}
+
+// Type implements message.Type.
+func (*Rsetattrclunk) Type() MsgType {
+	return MsgRsetattrclunk
+}
+
+// String implements fmt.Stringer.
+func (r *Rsetattrclunk) String() string {
+	return "Rsetattrclunk{}"
+}
+
 // Tremove is a remove request.
 //
 // This will eventually be replaced by Tunlinkat.
@@ -2657,6 +2715,8 @@ func init() {
 	msgRegistry.register(MsgRlconnect, func() message { return &Rlconnect{} })
 	msgRegistry.register(MsgTallocate, func() message { return &Tallocate{} })
 	msgRegistry.register(MsgRallocate, func() message { return &Rallocate{} })
+	msgRegistry.register(MsgTsetattrclunk, func() message { return &Tsetattrclunk{} })
+	msgRegistry.register(MsgRsetattrclunk, func() message { return &Rsetattrclunk{} })
 	msgRegistry.register(MsgTchannel, func() message { return &Tchannel{} })
 	msgRegistry.register(MsgRchannel, func() message { return &Rchannel{} })
 }
-- 
cgit v1.2.3