From 3471997294d25e29da423fb5d1cc7f4ea0bfd6b0 Mon Sep 17 00:00:00 2001
From: zhijian <djx@juicedata.io>
Date: Wed, 20 Nov 2024 13:26:46 +0800
Subject: [PATCH] vfs:support O_TMPFILE flag

---
 go.mod                |  2 +-
 go.sum                |  4 ++--
 pkg/meta/base.go      |  3 +++
 pkg/meta/interface.go |  1 +
 pkg/vfs/vfs.go        | 18 ++++++++++++++++++
 5 files changed, 25 insertions(+), 3 deletions(-)

diff --git a/go.mod b/go.mod
index 409aa74535c7..286d9fdbb894 100644
--- a/go.mod
+++ b/go.mod
@@ -249,7 +249,7 @@ require (
 
 replace github.com/minio/minio v0.0.0-20210206053228-97fe57bba92c => github.com/juicedata/minio v0.0.0-20240912134328-6a47725331ab
 
-replace github.com/hanwen/go-fuse/v2 v2.1.1-0.20210611132105-24a1dfe6b4f8 => github.com/juicedata/go-fuse/v2 v2.1.1-0.20240809072820-d78c97ed7b7a
+replace github.com/hanwen/go-fuse/v2 v2.1.1-0.20210611132105-24a1dfe6b4f8 => github.com/juicedata/go-fuse/v2 v2.1.1-0.20241119160225-81ccbb4066e4
 
 replace github.com/dgrijalva/jwt-go v3.2.0+incompatible => github.com/golang-jwt/jwt v3.2.1+incompatible
 
diff --git a/go.sum b/go.sum
index be59fe1a0e2a..623a3d0c48a8 100644
--- a/go.sum
+++ b/go.sum
@@ -501,8 +501,8 @@ github.com/jtolds/gls v4.20.0+incompatible h1:xdiiI2gbIgH/gLH7ADydsJ1uDOEzR8yvV7
 github.com/jtolds/gls v4.20.0+incompatible/go.mod h1:QJZ7F/aHp+rZTRtaJ1ow/lLfFfVYBRgL+9YlvaHOwJU=
 github.com/juicedata/cli/v2 v2.19.4-0.20230605075551-9c9c5c0dce83 h1:RyHTka3jCnTaUqfRYjlwcQlr53aasmkvHEbYLXthqr8=
 github.com/juicedata/cli/v2 v2.19.4-0.20230605075551-9c9c5c0dce83/go.mod h1:1CNUng3PtjQMtRzJO4FMXBQvkGtuYRxxiR9xMa7jMwI=
-github.com/juicedata/go-fuse/v2 v2.1.1-0.20240809072820-d78c97ed7b7a h1:Rzopfv1+KpROzMWd6NVAs1wTjr5bc5ZdzIhIs0u5XBc=
-github.com/juicedata/go-fuse/v2 v2.1.1-0.20240809072820-d78c97ed7b7a/go.mod h1:xKwi1cF7nXAOBCXujD5ie0ZKsxc8GGSA1rlMJc+8IJs=
+github.com/juicedata/go-fuse/v2 v2.1.1-0.20241119160225-81ccbb4066e4 h1:lMjWJaHLita+9s8z174ZUp8L1MtIMUl0FCau/dfBJsQ=
+github.com/juicedata/go-fuse/v2 v2.1.1-0.20241119160225-81ccbb4066e4/go.mod h1:xKwi1cF7nXAOBCXujD5ie0ZKsxc8GGSA1rlMJc+8IJs=
 github.com/juicedata/go-nfs-client v0.0.0-20231018052507-dbca444fa7e8 h1:mVVipCbohnzKZPiHGzFncLKEJZpypqjpGr4End2PP48=
 github.com/juicedata/go-nfs-client v0.0.0-20231018052507-dbca444fa7e8/go.mod h1:xOMqi3lOrcGe9uZLnSzgaq94Vc3oz6VPCNDLJUnXpKs=
 github.com/juicedata/godaemon v0.0.0-20210629045518-3da5144a127d h1:kpQMvNZJKGY3PTt7OSoahYc4nM0HY67SvK0YyS0GLwA=
diff --git a/pkg/meta/base.go b/pkg/meta/base.go
index 8279efffc63d..37edc8080556 100644
--- a/pkg/meta/base.go
+++ b/pkg/meta/base.go
@@ -1180,6 +1180,9 @@ func (m *baseMeta) Link(ctx Context, inode, parent Ino, name string, attr *Attr)
 	if attr.Typ == TypeDirectory {
 		return syscall.EPERM
 	}
+	if attr.Flags*FlagTmpFile != 0 {
+		return syscall.ENOENT
+	}
 	if m.checkDirQuota(ctx, parent, align4K(attr.Length), 1) {
 		return syscall.EDQUOT
 	}
diff --git a/pkg/meta/interface.go b/pkg/meta/interface.go
index a601c6bc7eea..65b1d1345225 100644
--- a/pkg/meta/interface.go
+++ b/pkg/meta/interface.go
@@ -93,6 +93,7 @@ const (
 const (
 	FlagImmutable = 1 << iota
 	FlagAppend
+	FlagTmpFile
 )
 
 const (
diff --git a/pkg/vfs/vfs.go b/pkg/vfs/vfs.go
index c46c91aa1d4d..84f48fe935ae 100644
--- a/pkg/vfs/vfs.go
+++ b/pkg/vfs/vfs.go
@@ -27,6 +27,7 @@ import (
 	"syscall"
 	"time"
 
+	"github.com/google/uuid"
 	"github.com/juicedata/juicefs/pkg/acl"
 	"github.com/juicedata/juicefs/pkg/chunk"
 	"github.com/juicedata/juicefs/pkg/meta"
@@ -474,10 +475,17 @@ func (v *VFS) Releasedir(ctx Context, ino Ino, fh uint64) int {
 	return 0
 }
 
+const O_TMPFILE = 020000000
+
 func (v *VFS) Create(ctx Context, parent Ino, name string, mode uint16, cumask uint16, flags uint32) (entry *meta.Entry, fh uint64, err syscall.Errno) {
 	defer func() {
 		logit(ctx, "create", err, "(%d,%s,%s:0%04o):%s [fh:%d]", parent, name, smode(mode), mode, (*Entry)(entry), fh)
 	}()
+	// O_TMPFILE support
+	doUnlink := runtime.GOOS == "linux" && flags&O_TMPFILE != 0
+	if doUnlink {
+		name = fmt.Sprintf("tmpfile_%s", uuid.New().String())
+	}
 	if parent == rootID && IsSpecialName(name) {
 		err = syscall.EEXIST
 		return
@@ -499,6 +507,16 @@ func (v *VFS) Create(ctx Context, parent Ino, name string, mode uint16, cumask u
 		entry = &meta.Entry{Inode: inode, Attr: attr}
 		v.invalidateDirHandle(parent, name, inode, attr)
 	}
+
+	if doUnlink {
+		if flags&syscall.O_EXCL != 0 {
+			attr.Flags |= meta.FlagTmpFile
+			if err = v.Meta.SetAttr(ctx, inode, uint16(meta.SetAttrFlag), 0, attr); err != 0 {
+				return
+			}
+		}
+		err = v.Unlink(ctx, parent, name)
+	}
 	return
 }