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-rw-r--r--pkg/sentry/fsimpl/tmpfs/BUILD125
-rw-r--r--pkg/sentry/fsimpl/tmpfs/benchmark_test.go486
-rw-r--r--pkg/sentry/fsimpl/tmpfs/dentry_list.go193
-rw-r--r--pkg/sentry/fsimpl/tmpfs/fstree.go46
-rw-r--r--pkg/sentry/fsimpl/tmpfs/inode_refs.go118
-rw-r--r--pkg/sentry/fsimpl/tmpfs/pipe_test.go238
-rw-r--r--pkg/sentry/fsimpl/tmpfs/regular_file_test.go349
-rw-r--r--pkg/sentry/fsimpl/tmpfs/stat_test.go236
-rw-r--r--pkg/sentry/fsimpl/tmpfs/tmpfs_state_autogen.go88
-rw-r--r--pkg/sentry/fsimpl/tmpfs/tmpfs_test.go156
10 files changed, 445 insertions, 1590 deletions
diff --git a/pkg/sentry/fsimpl/tmpfs/BUILD b/pkg/sentry/fsimpl/tmpfs/BUILD
deleted file mode 100644
index 5cd428d64..000000000
--- a/pkg/sentry/fsimpl/tmpfs/BUILD
+++ /dev/null
@@ -1,125 +0,0 @@
-load("//tools:defs.bzl", "go_library", "go_test")
-load("//tools/go_generics:defs.bzl", "go_template_instance")
-
-licenses(["notice"])
-
-go_template_instance(
- name = "dentry_list",
- out = "dentry_list.go",
- package = "tmpfs",
- prefix = "dentry",
- template = "//pkg/ilist:generic_list",
- types = {
- "Element": "*dentry",
- "Linker": "*dentry",
- },
-)
-
-go_template_instance(
- name = "fstree",
- out = "fstree.go",
- package = "tmpfs",
- prefix = "generic",
- template = "//pkg/sentry/vfs/genericfstree:generic_fstree",
- types = {
- "Dentry": "dentry",
- },
-)
-
-go_template_instance(
- name = "inode_refs",
- out = "inode_refs.go",
- package = "tmpfs",
- prefix = "inode",
- template = "//pkg/refs_vfs2:refs_template",
- types = {
- "T": "inode",
- },
-)
-
-go_library(
- name = "tmpfs",
- srcs = [
- "dentry_list.go",
- "device_file.go",
- "directory.go",
- "filesystem.go",
- "fstree.go",
- "inode_refs.go",
- "named_pipe.go",
- "regular_file.go",
- "socket_file.go",
- "symlink.go",
- "tmpfs.go",
- ],
- visibility = ["//pkg/sentry:internal"],
- deps = [
- "//pkg/abi/linux",
- "//pkg/amutex",
- "//pkg/context",
- "//pkg/fspath",
- "//pkg/log",
- "//pkg/refs",
- "//pkg/safemem",
- "//pkg/sentry/arch",
- "//pkg/sentry/fs",
- "//pkg/sentry/fs/fsutil",
- "//pkg/sentry/fs/lock",
- "//pkg/sentry/kernel/auth",
- "//pkg/sentry/kernel/pipe",
- "//pkg/sentry/kernel/time",
- "//pkg/sentry/memmap",
- "//pkg/sentry/pgalloc",
- "//pkg/sentry/platform",
- "//pkg/sentry/socket/unix/transport",
- "//pkg/sentry/uniqueid",
- "//pkg/sentry/usage",
- "//pkg/sentry/vfs",
- "//pkg/sentry/vfs/memxattr",
- "//pkg/sync",
- "//pkg/syserror",
- "//pkg/usermem",
- ],
-)
-
-go_test(
- name = "benchmark_test",
- size = "small",
- srcs = ["benchmark_test.go"],
- deps = [
- ":tmpfs",
- "//pkg/abi/linux",
- "//pkg/context",
- "//pkg/fspath",
- "//pkg/refs",
- "//pkg/sentry/contexttest",
- "//pkg/sentry/fs",
- "//pkg/sentry/fs/tmpfs",
- "//pkg/sentry/kernel/auth",
- "//pkg/sentry/vfs",
- "//pkg/syserror",
- ],
-)
-
-go_test(
- name = "tmpfs_test",
- size = "small",
- srcs = [
- "pipe_test.go",
- "regular_file_test.go",
- "stat_test.go",
- "tmpfs_test.go",
- ],
- library = ":tmpfs",
- deps = [
- "//pkg/abi/linux",
- "//pkg/context",
- "//pkg/fspath",
- "//pkg/sentry/contexttest",
- "//pkg/sentry/fs/lock",
- "//pkg/sentry/kernel/auth",
- "//pkg/sentry/vfs",
- "//pkg/syserror",
- "//pkg/usermem",
- ],
-)
diff --git a/pkg/sentry/fsimpl/tmpfs/benchmark_test.go b/pkg/sentry/fsimpl/tmpfs/benchmark_test.go
deleted file mode 100644
index e5a4218e8..000000000
--- a/pkg/sentry/fsimpl/tmpfs/benchmark_test.go
+++ /dev/null
@@ -1,486 +0,0 @@
-// Copyright 2019 The gVisor Authors.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package benchmark_test
-
-import (
- "fmt"
- "runtime"
- "strings"
- "testing"
-
- "gvisor.dev/gvisor/pkg/abi/linux"
- "gvisor.dev/gvisor/pkg/context"
- "gvisor.dev/gvisor/pkg/fspath"
- "gvisor.dev/gvisor/pkg/refs"
- "gvisor.dev/gvisor/pkg/sentry/contexttest"
- "gvisor.dev/gvisor/pkg/sentry/fs"
- _ "gvisor.dev/gvisor/pkg/sentry/fs/tmpfs"
- "gvisor.dev/gvisor/pkg/sentry/fsimpl/tmpfs"
- "gvisor.dev/gvisor/pkg/sentry/kernel/auth"
- "gvisor.dev/gvisor/pkg/sentry/vfs"
- "gvisor.dev/gvisor/pkg/syserror"
-)
-
-// Differences from stat_benchmark:
-//
-// - Syscall interception, CopyInPath, copyOutStat, and overlayfs overheads are
-// not included.
-//
-// - *MountStat benchmarks use a tmpfs root mount and a tmpfs submount at /tmp.
-// Non-MountStat benchmarks use a tmpfs root mount and no submounts.
-// stat_benchmark uses a varying root mount, a tmpfs submount at /tmp, and a
-// subdirectory /tmp/<top_dir> (assuming TEST_TMPDIR == "/tmp"). Thus
-// stat_benchmark at depth 1 does a comparable amount of work to *MountStat
-// benchmarks at depth 2, and non-MountStat benchmarks at depth 3.
-var depths = []int{1, 2, 3, 8, 64, 100}
-
-const (
- mountPointName = "tmp"
- filename = "gvisor_test_temp_0_1557494568"
-)
-
-// This is copied from syscalls/linux/sys_file.go, with the dependency on
-// kernel.Task stripped out.
-func fileOpOn(ctx context.Context, mntns *fs.MountNamespace, root, wd *fs.Dirent, dirFD int32, path string, resolve bool, fn func(root *fs.Dirent, d *fs.Dirent) error) error {
- var (
- d *fs.Dirent // The file.
- rel *fs.Dirent // The relative directory for search (if required.)
- err error
- )
-
- // Extract the working directory (maybe).
- if len(path) > 0 && path[0] == '/' {
- // Absolute path; rel can be nil.
- } else if dirFD == linux.AT_FDCWD {
- // Need to reference the working directory.
- rel = wd
- } else {
- // Need to extract the given FD.
- return syserror.EBADF
- }
-
- // Lookup the node.
- remainingTraversals := uint(linux.MaxSymlinkTraversals)
- if resolve {
- d, err = mntns.FindInode(ctx, root, rel, path, &remainingTraversals)
- } else {
- d, err = mntns.FindLink(ctx, root, rel, path, &remainingTraversals)
- }
- if err != nil {
- return err
- }
-
- err = fn(root, d)
- d.DecRef(ctx)
- return err
-}
-
-func BenchmarkVFS1TmpfsStat(b *testing.B) {
- for _, depth := range depths {
- b.Run(fmt.Sprintf("%d", depth), func(b *testing.B) {
- ctx := contexttest.Context(b)
-
- // Create VFS.
- tmpfsFS, ok := fs.FindFilesystem("tmpfs")
- if !ok {
- b.Fatalf("failed to find tmpfs filesystem type")
- }
- rootInode, err := tmpfsFS.Mount(ctx, "tmpfs", fs.MountSourceFlags{}, "", nil)
- if err != nil {
- b.Fatalf("failed to create tmpfs root mount: %v", err)
- }
- mntns, err := fs.NewMountNamespace(ctx, rootInode)
- if err != nil {
- b.Fatalf("failed to create mount namespace: %v", err)
- }
- defer mntns.DecRef(ctx)
-
- var filePathBuilder strings.Builder
- filePathBuilder.WriteByte('/')
-
- // Create nested directories with given depth.
- root := mntns.Root()
- defer root.DecRef(ctx)
- d := root
- d.IncRef()
- defer d.DecRef(ctx)
- for i := depth; i > 0; i-- {
- name := fmt.Sprintf("%d", i)
- if err := d.Inode.CreateDirectory(ctx, d, name, fs.FilePermsFromMode(0755)); err != nil {
- b.Fatalf("failed to create directory %q: %v", name, err)
- }
- next, err := d.Walk(ctx, root, name)
- if err != nil {
- b.Fatalf("failed to walk to directory %q: %v", name, err)
- }
- d.DecRef(ctx)
- d = next
- filePathBuilder.WriteString(name)
- filePathBuilder.WriteByte('/')
- }
-
- // Create the file that will be stat'd.
- file, err := d.Inode.Create(ctx, d, filename, fs.FileFlags{Read: true, Write: true}, fs.FilePermsFromMode(0644))
- if err != nil {
- b.Fatalf("failed to create file %q: %v", filename, err)
- }
- file.DecRef(ctx)
- filePathBuilder.WriteString(filename)
- filePath := filePathBuilder.String()
-
- dirPath := false
- runtime.GC()
- b.ResetTimer()
- for i := 0; i < b.N; i++ {
- err := fileOpOn(ctx, mntns, root, root, linux.AT_FDCWD, filePath, true /* resolve */, func(root *fs.Dirent, d *fs.Dirent) error {
- if dirPath && !fs.IsDir(d.Inode.StableAttr) {
- return syserror.ENOTDIR
- }
- uattr, err := d.Inode.UnstableAttr(ctx)
- if err != nil {
- return err
- }
- // Sanity check.
- if uattr.Perms.User.Execute {
- b.Fatalf("got wrong permissions (%0o)", uattr.Perms.LinuxMode())
- }
- return nil
- })
- if err != nil {
- b.Fatalf("stat(%q) failed: %v", filePath, err)
- }
- }
- // Don't include deferred cleanup in benchmark time.
- b.StopTimer()
- })
- }
-}
-
-func BenchmarkVFS2TmpfsStat(b *testing.B) {
- for _, depth := range depths {
- b.Run(fmt.Sprintf("%d", depth), func(b *testing.B) {
- ctx := contexttest.Context(b)
- creds := auth.CredentialsFromContext(ctx)
-
- // Create VFS.
- vfsObj := vfs.VirtualFilesystem{}
- if err := vfsObj.Init(ctx); err != nil {
- b.Fatalf("VFS init: %v", err)
- }
- vfsObj.MustRegisterFilesystemType("tmpfs", tmpfs.FilesystemType{}, &vfs.RegisterFilesystemTypeOptions{
- AllowUserMount: true,
- })
- mntns, err := vfsObj.NewMountNamespace(ctx, creds, "", "tmpfs", &vfs.GetFilesystemOptions{})
- if err != nil {
- b.Fatalf("failed to create tmpfs root mount: %v", err)
- }
- defer mntns.DecRef(ctx)
-
- var filePathBuilder strings.Builder
- filePathBuilder.WriteByte('/')
-
- // Create nested directories with given depth.
- root := mntns.Root()
- defer root.DecRef(ctx)
- vd := root
- vd.IncRef()
- for i := depth; i > 0; i-- {
- name := fmt.Sprintf("%d", i)
- pop := vfs.PathOperation{
- Root: root,
- Start: vd,
- Path: fspath.Parse(name),
- }
- if err := vfsObj.MkdirAt(ctx, creds, &pop, &vfs.MkdirOptions{
- Mode: 0755,
- }); err != nil {
- b.Fatalf("failed to create directory %q: %v", name, err)
- }
- nextVD, err := vfsObj.GetDentryAt(ctx, creds, &pop, &vfs.GetDentryOptions{})
- if err != nil {
- b.Fatalf("failed to walk to directory %q: %v", name, err)
- }
- vd.DecRef(ctx)
- vd = nextVD
- filePathBuilder.WriteString(name)
- filePathBuilder.WriteByte('/')
- }
-
- // Create the file that will be stat'd.
- fd, err := vfsObj.OpenAt(ctx, creds, &vfs.PathOperation{
- Root: root,
- Start: vd,
- Path: fspath.Parse(filename),
- FollowFinalSymlink: true,
- }, &vfs.OpenOptions{
- Flags: linux.O_RDWR | linux.O_CREAT | linux.O_EXCL,
- Mode: 0644,
- })
- vd.DecRef(ctx)
- vd = vfs.VirtualDentry{}
- if err != nil {
- b.Fatalf("failed to create file %q: %v", filename, err)
- }
- defer fd.DecRef(ctx)
- filePathBuilder.WriteString(filename)
- filePath := filePathBuilder.String()
-
- runtime.GC()
- b.ResetTimer()
- for i := 0; i < b.N; i++ {
- stat, err := vfsObj.StatAt(ctx, creds, &vfs.PathOperation{
- Root: root,
- Start: root,
- Path: fspath.Parse(filePath),
- FollowFinalSymlink: true,
- }, &vfs.StatOptions{})
- if err != nil {
- b.Fatalf("stat(%q) failed: %v", filePath, err)
- }
- // Sanity check.
- if stat.Mode&^linux.S_IFMT != 0644 {
- b.Fatalf("got wrong permissions (%0o)", stat.Mode)
- }
- }
- // Don't include deferred cleanup in benchmark time.
- b.StopTimer()
- })
- }
-}
-
-func BenchmarkVFS1TmpfsMountStat(b *testing.B) {
- for _, depth := range depths {
- b.Run(fmt.Sprintf("%d", depth), func(b *testing.B) {
- ctx := contexttest.Context(b)
-
- // Create VFS.
- tmpfsFS, ok := fs.FindFilesystem("tmpfs")
- if !ok {
- b.Fatalf("failed to find tmpfs filesystem type")
- }
- rootInode, err := tmpfsFS.Mount(ctx, "tmpfs", fs.MountSourceFlags{}, "", nil)
- if err != nil {
- b.Fatalf("failed to create tmpfs root mount: %v", err)
- }
- mntns, err := fs.NewMountNamespace(ctx, rootInode)
- if err != nil {
- b.Fatalf("failed to create mount namespace: %v", err)
- }
- defer mntns.DecRef(ctx)
-
- var filePathBuilder strings.Builder
- filePathBuilder.WriteByte('/')
-
- // Create and mount the submount.
- root := mntns.Root()
- defer root.DecRef(ctx)
- if err := root.Inode.CreateDirectory(ctx, root, mountPointName, fs.FilePermsFromMode(0755)); err != nil {
- b.Fatalf("failed to create mount point: %v", err)
- }
- mountPoint, err := root.Walk(ctx, root, mountPointName)
- if err != nil {
- b.Fatalf("failed to walk to mount point: %v", err)
- }
- defer mountPoint.DecRef(ctx)
- submountInode, err := tmpfsFS.Mount(ctx, "tmpfs", fs.MountSourceFlags{}, "", nil)
- if err != nil {
- b.Fatalf("failed to create tmpfs submount: %v", err)
- }
- if err := mntns.Mount(ctx, mountPoint, submountInode); err != nil {
- b.Fatalf("failed to mount tmpfs submount: %v", err)
- }
- filePathBuilder.WriteString(mountPointName)
- filePathBuilder.WriteByte('/')
-
- // Create nested directories with given depth.
- d, err := root.Walk(ctx, root, mountPointName)
- if err != nil {
- b.Fatalf("failed to walk to mount root: %v", err)
- }
- defer d.DecRef(ctx)
- for i := depth; i > 0; i-- {
- name := fmt.Sprintf("%d", i)
- if err := d.Inode.CreateDirectory(ctx, d, name, fs.FilePermsFromMode(0755)); err != nil {
- b.Fatalf("failed to create directory %q: %v", name, err)
- }
- next, err := d.Walk(ctx, root, name)
- if err != nil {
- b.Fatalf("failed to walk to directory %q: %v", name, err)
- }
- d.DecRef(ctx)
- d = next
- filePathBuilder.WriteString(name)
- filePathBuilder.WriteByte('/')
- }
-
- // Create the file that will be stat'd.
- file, err := d.Inode.Create(ctx, d, filename, fs.FileFlags{Read: true, Write: true}, fs.FilePermsFromMode(0644))
- if err != nil {
- b.Fatalf("failed to create file %q: %v", filename, err)
- }
- file.DecRef(ctx)
- filePathBuilder.WriteString(filename)
- filePath := filePathBuilder.String()
-
- dirPath := false
- runtime.GC()
- b.ResetTimer()
- for i := 0; i < b.N; i++ {
- err := fileOpOn(ctx, mntns, root, root, linux.AT_FDCWD, filePath, true /* resolve */, func(root *fs.Dirent, d *fs.Dirent) error {
- if dirPath && !fs.IsDir(d.Inode.StableAttr) {
- return syserror.ENOTDIR
- }
- uattr, err := d.Inode.UnstableAttr(ctx)
- if err != nil {
- return err
- }
- // Sanity check.
- if uattr.Perms.User.Execute {
- b.Fatalf("got wrong permissions (%0o)", uattr.Perms.LinuxMode())
- }
- return nil
- })
- if err != nil {
- b.Fatalf("stat(%q) failed: %v", filePath, err)
- }
- }
- // Don't include deferred cleanup in benchmark time.
- b.StopTimer()
- })
- }
-}
-
-func BenchmarkVFS2TmpfsMountStat(b *testing.B) {
- for _, depth := range depths {
- b.Run(fmt.Sprintf("%d", depth), func(b *testing.B) {
- ctx := contexttest.Context(b)
- creds := auth.CredentialsFromContext(ctx)
-
- // Create VFS.
- vfsObj := vfs.VirtualFilesystem{}
- if err := vfsObj.Init(ctx); err != nil {
- b.Fatalf("VFS init: %v", err)
- }
- vfsObj.MustRegisterFilesystemType("tmpfs", tmpfs.FilesystemType{}, &vfs.RegisterFilesystemTypeOptions{
- AllowUserMount: true,
- })
- mntns, err := vfsObj.NewMountNamespace(ctx, creds, "", "tmpfs", &vfs.GetFilesystemOptions{})
- if err != nil {
- b.Fatalf("failed to create tmpfs root mount: %v", err)
- }
- defer mntns.DecRef(ctx)
-
- var filePathBuilder strings.Builder
- filePathBuilder.WriteByte('/')
-
- // Create the mount point.
- root := mntns.Root()
- defer root.DecRef(ctx)
- pop := vfs.PathOperation{
- Root: root,
- Start: root,
- Path: fspath.Parse(mountPointName),
- }
- if err := vfsObj.MkdirAt(ctx, creds, &pop, &vfs.MkdirOptions{
- Mode: 0755,
- }); err != nil {
- b.Fatalf("failed to create mount point: %v", err)
- }
- // Save the mount point for later use.
- mountPoint, err := vfsObj.GetDentryAt(ctx, creds, &pop, &vfs.GetDentryOptions{})
- if err != nil {
- b.Fatalf("failed to walk to mount point: %v", err)
- }
- defer mountPoint.DecRef(ctx)
- // Create and mount the submount.
- if _, err := vfsObj.MountAt(ctx, creds, "", &pop, "tmpfs", &vfs.MountOptions{}); err != nil {
- b.Fatalf("failed to mount tmpfs submount: %v", err)
- }
- filePathBuilder.WriteString(mountPointName)
- filePathBuilder.WriteByte('/')
-
- // Create nested directories with given depth.
- vd, err := vfsObj.GetDentryAt(ctx, creds, &pop, &vfs.GetDentryOptions{})
- if err != nil {
- b.Fatalf("failed to walk to mount root: %v", err)
- }
- for i := depth; i > 0; i-- {
- name := fmt.Sprintf("%d", i)
- pop := vfs.PathOperation{
- Root: root,
- Start: vd,
- Path: fspath.Parse(name),
- }
- if err := vfsObj.MkdirAt(ctx, creds, &pop, &vfs.MkdirOptions{
- Mode: 0755,
- }); err != nil {
- b.Fatalf("failed to create directory %q: %v", name, err)
- }
- nextVD, err := vfsObj.GetDentryAt(ctx, creds, &pop, &vfs.GetDentryOptions{})
- if err != nil {
- b.Fatalf("failed to walk to directory %q: %v", name, err)
- }
- vd.DecRef(ctx)
- vd = nextVD
- filePathBuilder.WriteString(name)
- filePathBuilder.WriteByte('/')
- }
-
- // Create the file that will be stat'd.
- fd, err := vfsObj.OpenAt(ctx, creds, &vfs.PathOperation{
- Root: root,
- Start: vd,
- Path: fspath.Parse(filename),
- FollowFinalSymlink: true,
- }, &vfs.OpenOptions{
- Flags: linux.O_RDWR | linux.O_CREAT | linux.O_EXCL,
- Mode: 0644,
- })
- vd.DecRef(ctx)
- if err != nil {
- b.Fatalf("failed to create file %q: %v", filename, err)
- }
- fd.DecRef(ctx)
- filePathBuilder.WriteString(filename)
- filePath := filePathBuilder.String()
-
- runtime.GC()
- b.ResetTimer()
- for i := 0; i < b.N; i++ {
- stat, err := vfsObj.StatAt(ctx, creds, &vfs.PathOperation{
- Root: root,
- Start: root,
- Path: fspath.Parse(filePath),
- FollowFinalSymlink: true,
- }, &vfs.StatOptions{})
- if err != nil {
- b.Fatalf("stat(%q) failed: %v", filePath, err)
- }
- // Sanity check.
- if stat.Mode&^linux.S_IFMT != 0644 {
- b.Fatalf("got wrong permissions (%0o)", stat.Mode)
- }
- }
- // Don't include deferred cleanup in benchmark time.
- b.StopTimer()
- })
- }
-}
-
-func init() {
- // Turn off reference leak checking for a fair comparison between vfs1 and
- // vfs2.
- refs.SetLeakMode(refs.NoLeakChecking)
-}
diff --git a/pkg/sentry/fsimpl/tmpfs/dentry_list.go b/pkg/sentry/fsimpl/tmpfs/dentry_list.go
new file mode 100644
index 000000000..95e3d13d5
--- /dev/null
+++ b/pkg/sentry/fsimpl/tmpfs/dentry_list.go
@@ -0,0 +1,193 @@
+package tmpfs
+
+// ElementMapper provides an identity mapping by default.
+//
+// This can be replaced to provide a struct that maps elements to linker
+// objects, if they are not the same. An ElementMapper is not typically
+// required if: Linker is left as is, Element is left as is, or Linker and
+// Element are the same type.
+type dentryElementMapper struct{}
+
+// linkerFor maps an Element to a Linker.
+//
+// This default implementation should be inlined.
+//
+//go:nosplit
+func (dentryElementMapper) linkerFor(elem *dentry) *dentry { return elem }
+
+// List is an intrusive list. Entries can be added to or removed from the list
+// in O(1) time and with no additional memory allocations.
+//
+// The zero value for List is an empty list ready to use.
+//
+// To iterate over a list (where l is a List):
+// for e := l.Front(); e != nil; e = e.Next() {
+// // do something with e.
+// }
+//
+// +stateify savable
+type dentryList struct {
+ head *dentry
+ tail *dentry
+}
+
+// Reset resets list l to the empty state.
+func (l *dentryList) Reset() {
+ l.head = nil
+ l.tail = nil
+}
+
+// Empty returns true iff the list is empty.
+func (l *dentryList) Empty() bool {
+ return l.head == nil
+}
+
+// Front returns the first element of list l or nil.
+func (l *dentryList) Front() *dentry {
+ return l.head
+}
+
+// Back returns the last element of list l or nil.
+func (l *dentryList) Back() *dentry {
+ return l.tail
+}
+
+// Len returns the number of elements in the list.
+//
+// NOTE: This is an O(n) operation.
+func (l *dentryList) Len() (count int) {
+ for e := l.Front(); e != nil; e = (dentryElementMapper{}.linkerFor(e)).Next() {
+ count++
+ }
+ return count
+}
+
+// PushFront inserts the element e at the front of list l.
+func (l *dentryList) PushFront(e *dentry) {
+ linker := dentryElementMapper{}.linkerFor(e)
+ linker.SetNext(l.head)
+ linker.SetPrev(nil)
+ if l.head != nil {
+ dentryElementMapper{}.linkerFor(l.head).SetPrev(e)
+ } else {
+ l.tail = e
+ }
+
+ l.head = e
+}
+
+// PushBack inserts the element e at the back of list l.
+func (l *dentryList) PushBack(e *dentry) {
+ linker := dentryElementMapper{}.linkerFor(e)
+ linker.SetNext(nil)
+ linker.SetPrev(l.tail)
+ if l.tail != nil {
+ dentryElementMapper{}.linkerFor(l.tail).SetNext(e)
+ } else {
+ l.head = e
+ }
+
+ l.tail = e
+}
+
+// PushBackList inserts list m at the end of list l, emptying m.
+func (l *dentryList) PushBackList(m *dentryList) {
+ if l.head == nil {
+ l.head = m.head
+ l.tail = m.tail
+ } else if m.head != nil {
+ dentryElementMapper{}.linkerFor(l.tail).SetNext(m.head)
+ dentryElementMapper{}.linkerFor(m.head).SetPrev(l.tail)
+
+ l.tail = m.tail
+ }
+ m.head = nil
+ m.tail = nil
+}
+
+// InsertAfter inserts e after b.
+func (l *dentryList) InsertAfter(b, e *dentry) {
+ bLinker := dentryElementMapper{}.linkerFor(b)
+ eLinker := dentryElementMapper{}.linkerFor(e)
+
+ a := bLinker.Next()
+
+ eLinker.SetNext(a)
+ eLinker.SetPrev(b)
+ bLinker.SetNext(e)
+
+ if a != nil {
+ dentryElementMapper{}.linkerFor(a).SetPrev(e)
+ } else {
+ l.tail = e
+ }
+}
+
+// InsertBefore inserts e before a.
+func (l *dentryList) InsertBefore(a, e *dentry) {
+ aLinker := dentryElementMapper{}.linkerFor(a)
+ eLinker := dentryElementMapper{}.linkerFor(e)
+
+ b := aLinker.Prev()
+ eLinker.SetNext(a)
+ eLinker.SetPrev(b)
+ aLinker.SetPrev(e)
+
+ if b != nil {
+ dentryElementMapper{}.linkerFor(b).SetNext(e)
+ } else {
+ l.head = e
+ }
+}
+
+// Remove removes e from l.
+func (l *dentryList) Remove(e *dentry) {
+ linker := dentryElementMapper{}.linkerFor(e)
+ prev := linker.Prev()
+ next := linker.Next()
+
+ if prev != nil {
+ dentryElementMapper{}.linkerFor(prev).SetNext(next)
+ } else if l.head == e {
+ l.head = next
+ }
+
+ if next != nil {
+ dentryElementMapper{}.linkerFor(next).SetPrev(prev)
+ } else if l.tail == e {
+ l.tail = prev
+ }
+
+ linker.SetNext(nil)
+ linker.SetPrev(nil)
+}
+
+// Entry is a default implementation of Linker. Users can add anonymous fields
+// of this type to their structs to make them automatically implement the
+// methods needed by List.
+//
+// +stateify savable
+type dentryEntry struct {
+ next *dentry
+ prev *dentry
+}
+
+// Next returns the entry that follows e in the list.
+func (e *dentryEntry) Next() *dentry {
+ return e.next
+}
+
+// Prev returns the entry that precedes e in the list.
+func (e *dentryEntry) Prev() *dentry {
+ return e.prev
+}
+
+// SetNext assigns 'entry' as the entry that follows e in the list.
+func (e *dentryEntry) SetNext(elem *dentry) {
+ e.next = elem
+}
+
+// SetPrev assigns 'entry' as the entry that precedes e in the list.
+func (e *dentryEntry) SetPrev(elem *dentry) {
+ e.prev = elem
+}
diff --git a/pkg/sentry/fsimpl/tmpfs/fstree.go b/pkg/sentry/fsimpl/tmpfs/fstree.go
new file mode 100644
index 000000000..2dd98a921
--- /dev/null
+++ b/pkg/sentry/fsimpl/tmpfs/fstree.go
@@ -0,0 +1,46 @@
+package tmpfs
+
+import (
+ "gvisor.dev/gvisor/pkg/fspath"
+ "gvisor.dev/gvisor/pkg/sentry/vfs"
+)
+
+// IsAncestorDentry returns true if d is an ancestor of d2; that is, d is
+// either d2's parent or an ancestor of d2's parent.
+func genericIsAncestorDentry(d, d2 *dentry) bool {
+ for d2 != nil {
+ if d2.parent == d {
+ return true
+ }
+ if d2.parent == d2 {
+ return false
+ }
+ d2 = d2.parent
+ }
+ return false
+}
+
+// ParentOrSelf returns d.parent. If d.parent is nil, ParentOrSelf returns d.
+func genericParentOrSelf(d *dentry) *dentry {
+ if d.parent != nil {
+ return d.parent
+ }
+ return d
+}
+
+// PrependPath is a generic implementation of FilesystemImpl.PrependPath().
+func genericPrependPath(vfsroot vfs.VirtualDentry, mnt *vfs.Mount, d *dentry, b *fspath.Builder) error {
+ for {
+ if mnt == vfsroot.Mount() && &d.vfsd == vfsroot.Dentry() {
+ return vfs.PrependPathAtVFSRootError{}
+ }
+ if &d.vfsd == mnt.Root() {
+ return nil
+ }
+ if d.parent == nil {
+ return vfs.PrependPathAtNonMountRootError{}
+ }
+ b.PrependComponent(d.name)
+ d = d.parent
+ }
+}
diff --git a/pkg/sentry/fsimpl/tmpfs/inode_refs.go b/pkg/sentry/fsimpl/tmpfs/inode_refs.go
new file mode 100644
index 000000000..4f4037adb
--- /dev/null
+++ b/pkg/sentry/fsimpl/tmpfs/inode_refs.go
@@ -0,0 +1,118 @@
+package tmpfs
+
+import (
+ "runtime"
+ "sync/atomic"
+
+ "fmt"
+ "gvisor.dev/gvisor/pkg/log"
+ refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
+)
+
+// ownerType is used to customize logging. Note that we use a pointer to T so
+// that we do not copy the entire object when passed as a format parameter.
+var inodeownerType *inode
+
+// Refs implements refs.RefCounter. It keeps a reference count using atomic
+// operations and calls the destructor when the count reaches zero.
+//
+// Note that the number of references is actually refCount + 1 so that a default
+// zero-value Refs object contains one reference.
+//
+// TODO(gvisor.dev/issue/1486): Store stack traces when leak check is enabled in
+// a map with 16-bit hashes, and store the hash in the top 16 bits of refCount.
+// This will allow us to add stack trace information to the leak messages
+// without growing the size of Refs.
+//
+// +stateify savable
+type inodeRefs struct {
+ // refCount is composed of two fields:
+ //
+ // [32-bit speculative references]:[32-bit real references]
+ //
+ // Speculative references are used for TryIncRef, to avoid a CompareAndSwap
+ // loop. See IncRef, DecRef and TryIncRef for details of how these fields are
+ // used.
+ refCount int64
+}
+
+func (r *inodeRefs) finalize() {
+ var note string
+ switch refs_vfs1.GetLeakMode() {
+ case refs_vfs1.NoLeakChecking:
+ return
+ case refs_vfs1.UninitializedLeakChecking:
+ note = "(Leak checker uninitialized): "
+ }
+ if n := r.ReadRefs(); n != 0 {
+ log.Warningf("%sRefs %p owned by %T garbage collected with ref count of %d (want 0)", note, r, inodeownerType, n)
+ }
+}
+
+// EnableLeakCheck checks for reference leaks when Refs gets garbage collected.
+func (r *inodeRefs) EnableLeakCheck() {
+ if refs_vfs1.GetLeakMode() != refs_vfs1.NoLeakChecking {
+ runtime.SetFinalizer(r, (*inodeRefs).finalize)
+ }
+}
+
+// ReadRefs returns the current number of references. The returned count is
+// inherently racy and is unsafe to use without external synchronization.
+func (r *inodeRefs) ReadRefs() int64 {
+
+ return atomic.LoadInt64(&r.refCount) + 1
+}
+
+// IncRef implements refs.RefCounter.IncRef.
+//
+//go:nosplit
+func (r *inodeRefs) IncRef() {
+ if v := atomic.AddInt64(&r.refCount, 1); v <= 0 {
+ panic(fmt.Sprintf("Incrementing non-positive ref count %p owned by %T", r, inodeownerType))
+ }
+}
+
+// TryIncRef implements refs.RefCounter.TryIncRef.
+//
+// To do this safely without a loop, a speculative reference is first acquired
+// on the object. This allows multiple concurrent TryIncRef calls to distinguish
+// other TryIncRef calls from genuine references held.
+//
+//go:nosplit
+func (r *inodeRefs) TryIncRef() bool {
+ const speculativeRef = 1 << 32
+ v := atomic.AddInt64(&r.refCount, speculativeRef)
+ if int32(v) < 0 {
+
+ atomic.AddInt64(&r.refCount, -speculativeRef)
+ return false
+ }
+
+ atomic.AddInt64(&r.refCount, -speculativeRef+1)
+ return true
+}
+
+// DecRef implements refs.RefCounter.DecRef.
+//
+// Note that speculative references are counted here. Since they were added
+// prior to real references reaching zero, they will successfully convert to
+// real references. In other words, we see speculative references only in the
+// following case:
+//
+// A: TryIncRef [speculative increase => sees non-negative references]
+// B: DecRef [real decrease]
+// A: TryIncRef [transform speculative to real]
+//
+//go:nosplit
+func (r *inodeRefs) DecRef(destroy func()) {
+ switch v := atomic.AddInt64(&r.refCount, -1); {
+ case v < -1:
+ panic(fmt.Sprintf("Decrementing non-positive ref count %p, owned by %T", r, inodeownerType))
+
+ case v == -1:
+
+ if destroy != nil {
+ destroy()
+ }
+ }
+}
diff --git a/pkg/sentry/fsimpl/tmpfs/pipe_test.go b/pkg/sentry/fsimpl/tmpfs/pipe_test.go
deleted file mode 100644
index ec2701d8b..000000000
--- a/pkg/sentry/fsimpl/tmpfs/pipe_test.go
+++ /dev/null
@@ -1,238 +0,0 @@
-// Copyright 2019 The gVisor Authors.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package tmpfs
-
-import (
- "bytes"
- "testing"
-
- "gvisor.dev/gvisor/pkg/abi/linux"
- "gvisor.dev/gvisor/pkg/context"
- "gvisor.dev/gvisor/pkg/fspath"
- "gvisor.dev/gvisor/pkg/sentry/contexttest"
- "gvisor.dev/gvisor/pkg/sentry/kernel/auth"
- "gvisor.dev/gvisor/pkg/sentry/vfs"
- "gvisor.dev/gvisor/pkg/syserror"
- "gvisor.dev/gvisor/pkg/usermem"
-)
-
-const fileName = "mypipe"
-
-func TestSeparateFDs(t *testing.T) {
- ctx, creds, vfsObj, root := setup(t)
- defer root.DecRef(ctx)
-
- // Open the read side. This is done in a concurrently because opening
- // One end the pipe blocks until the other end is opened.
- pop := vfs.PathOperation{
- Root: root,
- Start: root,
- Path: fspath.Parse(fileName),
- FollowFinalSymlink: true,
- }
- rfdchan := make(chan *vfs.FileDescription)
- go func() {
- openOpts := vfs.OpenOptions{Flags: linux.O_RDONLY}
- rfd, _ := vfsObj.OpenAt(ctx, creds, &pop, &openOpts)
- rfdchan <- rfd
- }()
-
- // Open the write side.
- openOpts := vfs.OpenOptions{Flags: linux.O_WRONLY}
- wfd, err := vfsObj.OpenAt(ctx, creds, &pop, &openOpts)
- if err != nil {
- t.Fatalf("failed to open pipe for writing %q: %v", fileName, err)
- }
- defer wfd.DecRef(ctx)
-
- rfd, ok := <-rfdchan
- if !ok {
- t.Fatalf("failed to open pipe for reading %q", fileName)
- }
- defer rfd.DecRef(ctx)
-
- const msg = "vamos azul"
- checkEmpty(ctx, t, rfd)
- checkWrite(ctx, t, wfd, msg)
- checkRead(ctx, t, rfd, msg)
-}
-
-func TestNonblockingRead(t *testing.T) {
- ctx, creds, vfsObj, root := setup(t)
- defer root.DecRef(ctx)
-
- // Open the read side as nonblocking.
- pop := vfs.PathOperation{
- Root: root,
- Start: root,
- Path: fspath.Parse(fileName),
- FollowFinalSymlink: true,
- }
- openOpts := vfs.OpenOptions{Flags: linux.O_RDONLY | linux.O_NONBLOCK}
- rfd, err := vfsObj.OpenAt(ctx, creds, &pop, &openOpts)
- if err != nil {
- t.Fatalf("failed to open pipe for reading %q: %v", fileName, err)
- }
- defer rfd.DecRef(ctx)
-
- // Open the write side.
- openOpts = vfs.OpenOptions{Flags: linux.O_WRONLY}
- wfd, err := vfsObj.OpenAt(ctx, creds, &pop, &openOpts)
- if err != nil {
- t.Fatalf("failed to open pipe for writing %q: %v", fileName, err)
- }
- defer wfd.DecRef(ctx)
-
- const msg = "geh blau"
- checkEmpty(ctx, t, rfd)
- checkWrite(ctx, t, wfd, msg)
- checkRead(ctx, t, rfd, msg)
-}
-
-func TestNonblockingWriteError(t *testing.T) {
- ctx, creds, vfsObj, root := setup(t)
- defer root.DecRef(ctx)
-
- // Open the write side as nonblocking, which should return ENXIO.
- pop := vfs.PathOperation{
- Root: root,
- Start: root,
- Path: fspath.Parse(fileName),
- FollowFinalSymlink: true,
- }
- openOpts := vfs.OpenOptions{Flags: linux.O_WRONLY | linux.O_NONBLOCK}
- _, err := vfsObj.OpenAt(ctx, creds, &pop, &openOpts)
- if err != syserror.ENXIO {
- t.Fatalf("expected ENXIO, but got error: %v", err)
- }
-}
-
-func TestSingleFD(t *testing.T) {
- ctx, creds, vfsObj, root := setup(t)
- defer root.DecRef(ctx)
-
- // Open the pipe as readable and writable.
- pop := vfs.PathOperation{
- Root: root,
- Start: root,
- Path: fspath.Parse(fileName),
- FollowFinalSymlink: true,
- }
- openOpts := vfs.OpenOptions{Flags: linux.O_RDWR}
- fd, err := vfsObj.OpenAt(ctx, creds, &pop, &openOpts)
- if err != nil {
- t.Fatalf("failed to open pipe for writing %q: %v", fileName, err)
- }
- defer fd.DecRef(ctx)
-
- const msg = "forza blu"
- checkEmpty(ctx, t, fd)
- checkWrite(ctx, t, fd, msg)
- checkRead(ctx, t, fd, msg)
-}
-
-// setup creates a VFS with a pipe in the root directory at path fileName. The
-// returned VirtualDentry must be DecRef()'d be the caller. It calls t.Fatal
-// upon failure.
-func setup(t *testing.T) (context.Context, *auth.Credentials, *vfs.VirtualFilesystem, vfs.VirtualDentry) {
- ctx := contexttest.Context(t)
- creds := auth.CredentialsFromContext(ctx)
-
- // Create VFS.
- vfsObj := &vfs.VirtualFilesystem{}
- if err := vfsObj.Init(ctx); err != nil {
- t.Fatalf("VFS init: %v", err)
- }
- vfsObj.MustRegisterFilesystemType("tmpfs", FilesystemType{}, &vfs.RegisterFilesystemTypeOptions{
- AllowUserMount: true,
- })
- mntns, err := vfsObj.NewMountNamespace(ctx, creds, "", "tmpfs", &vfs.GetFilesystemOptions{})
- if err != nil {
- t.Fatalf("failed to create tmpfs root mount: %v", err)
- }
-
- // Create the pipe.
- root := mntns.Root()
- pop := vfs.PathOperation{
- Root: root,
- Start: root,
- Path: fspath.Parse(fileName),
- }
- mknodOpts := vfs.MknodOptions{Mode: linux.ModeNamedPipe | 0644}
- if err := vfsObj.MknodAt(ctx, creds, &pop, &mknodOpts); err != nil {
- t.Fatalf("failed to create file %q: %v", fileName, err)
- }
-
- // Sanity check: the file pipe exists and has the correct mode.
- stat, err := vfsObj.StatAt(ctx, creds, &vfs.PathOperation{
- Root: root,
- Start: root,
- Path: fspath.Parse(fileName),
- FollowFinalSymlink: true,
- }, &vfs.StatOptions{})
- if err != nil {
- t.Fatalf("stat(%q) failed: %v", fileName, err)
- }
- if stat.Mode&^linux.S_IFMT != 0644 {
- t.Errorf("got wrong permissions (%0o)", stat.Mode)
- }
- if stat.Mode&linux.S_IFMT != linux.ModeNamedPipe {
- t.Errorf("got wrong file type (%0o)", stat.Mode)
- }
-
- return ctx, creds, vfsObj, root
-}
-
-// checkEmpty calls t.Fatal if the pipe in fd is not empty.
-func checkEmpty(ctx context.Context, t *testing.T, fd *vfs.FileDescription) {
- readData := make([]byte, 1)
- dst := usermem.BytesIOSequence(readData)
- bytesRead, err := fd.Read(ctx, dst, vfs.ReadOptions{})
- if err != syserror.ErrWouldBlock {
- t.Fatalf("expected ErrWouldBlock reading from empty pipe %q, but got: %v", fileName, err)
- }
- if bytesRead != 0 {
- t.Fatalf("expected to read 0 bytes, but got %d", bytesRead)
- }
-}
-
-// checkWrite calls t.Fatal if it fails to write all of msg to fd.
-func checkWrite(ctx context.Context, t *testing.T, fd *vfs.FileDescription, msg string) {
- writeData := []byte(msg)
- src := usermem.BytesIOSequence(writeData)
- bytesWritten, err := fd.Write(ctx, src, vfs.WriteOptions{})
- if err != nil {
- t.Fatalf("error writing to pipe %q: %v", fileName, err)
- }
- if bytesWritten != int64(len(writeData)) {
- t.Fatalf("expected to write %d bytes, but wrote %d", len(writeData), bytesWritten)
- }
-}
-
-// checkRead calls t.Fatal if it fails to read msg from fd.
-func checkRead(ctx context.Context, t *testing.T, fd *vfs.FileDescription, msg string) {
- readData := make([]byte, len(msg))
- dst := usermem.BytesIOSequence(readData)
- bytesRead, err := fd.Read(ctx, dst, vfs.ReadOptions{})
- if err != nil {
- t.Fatalf("error reading from pipe %q: %v", fileName, err)
- }
- if bytesRead != int64(len(msg)) {
- t.Fatalf("expected to read %d bytes, but got %d", len(msg), bytesRead)
- }
- if !bytes.Equal(readData, []byte(msg)) {
- t.Fatalf("expected to read %q from pipe, but got %q", msg, string(readData))
- }
-}
diff --git a/pkg/sentry/fsimpl/tmpfs/regular_file_test.go b/pkg/sentry/fsimpl/tmpfs/regular_file_test.go
deleted file mode 100644
index 146c7fdfe..000000000
--- a/pkg/sentry/fsimpl/tmpfs/regular_file_test.go
+++ /dev/null
@@ -1,349 +0,0 @@
-// Copyright 2019 The gVisor Authors.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package tmpfs
-
-import (
- "bytes"
- "fmt"
- "io"
- "testing"
-
- "gvisor.dev/gvisor/pkg/abi/linux"
- "gvisor.dev/gvisor/pkg/sentry/contexttest"
- "gvisor.dev/gvisor/pkg/sentry/fs/lock"
- "gvisor.dev/gvisor/pkg/sentry/vfs"
- "gvisor.dev/gvisor/pkg/syserror"
- "gvisor.dev/gvisor/pkg/usermem"
-)
-
-// Test that we can write some data to a file and read it back.`
-func TestSimpleWriteRead(t *testing.T) {
- ctx := contexttest.Context(t)
- fd, cleanup, err := newFileFD(ctx, 0644)
- if err != nil {
- t.Fatal(err)
- }
- defer cleanup()
-
- // Write.
- data := []byte("foobarbaz")
- n, err := fd.Write(ctx, usermem.BytesIOSequence(data), vfs.WriteOptions{})
- if err != nil {
- t.Fatalf("fd.Write failed: %v", err)
- }
- if n != int64(len(data)) {
- t.Errorf("fd.Write got short write length %d, want %d", n, len(data))
- }
- if got, want := fd.Impl().(*regularFileFD).off, int64(len(data)); got != want {
- t.Errorf("fd.Write left offset at %d, want %d", got, want)
- }
-
- // Seek back to beginning.
- if _, err := fd.Seek(ctx, 0, linux.SEEK_SET); err != nil {
- t.Fatalf("fd.Seek failed: %v", err)
- }
- if got, want := fd.Impl().(*regularFileFD).off, int64(0); got != want {
- t.Errorf("fd.Seek(0) left offset at %d, want %d", got, want)
- }
-
- // Read.
- buf := make([]byte, len(data))
- n, err = fd.Read(ctx, usermem.BytesIOSequence(buf), vfs.ReadOptions{})
- if err != nil && err != io.EOF {
- t.Fatalf("fd.Read failed: %v", err)
- }
- if n != int64(len(data)) {
- t.Errorf("fd.Read got short read length %d, want %d", n, len(data))
- }
- if got, want := string(buf), string(data); got != want {
- t.Errorf("Read got %q want %s", got, want)
- }
- if got, want := fd.Impl().(*regularFileFD).off, int64(len(data)); got != want {
- t.Errorf("fd.Write left offset at %d, want %d", got, want)
- }
-}
-
-func TestPWrite(t *testing.T) {
- ctx := contexttest.Context(t)
- fd, cleanup, err := newFileFD(ctx, 0644)
- if err != nil {
- t.Fatal(err)
- }
- defer cleanup()
-
- // Fill file with 1k 'a's.
- data := bytes.Repeat([]byte{'a'}, 1000)
- n, err := fd.Write(ctx, usermem.BytesIOSequence(data), vfs.WriteOptions{})
- if err != nil {
- t.Fatalf("fd.Write failed: %v", err)
- }
- if n != int64(len(data)) {
- t.Errorf("fd.Write got short write length %d, want %d", n, len(data))
- }
-
- // Write "gVisor is awesome" at various offsets.
- buf := []byte("gVisor is awesome")
- offsets := []int{0, 1, 2, 10, 20, 50, 100, len(data) - 100, len(data) - 1, len(data), len(data) + 1}
- for _, offset := range offsets {
- name := fmt.Sprintf("PWrite offset=%d", offset)
- t.Run(name, func(t *testing.T) {
- n, err := fd.PWrite(ctx, usermem.BytesIOSequence(buf), int64(offset), vfs.WriteOptions{})
- if err != nil {
- t.Errorf("fd.PWrite got err %v want nil", err)
- }
- if n != int64(len(buf)) {
- t.Errorf("fd.PWrite got %d bytes want %d", n, len(buf))
- }
-
- // Update data to reflect expected file contents.
- if len(data) < offset+len(buf) {
- data = append(data, make([]byte, (offset+len(buf))-len(data))...)
- }
- copy(data[offset:], buf)
-
- // Read the whole file and compare with data.
- readBuf := make([]byte, len(data))
- n, err = fd.PRead(ctx, usermem.BytesIOSequence(readBuf), 0, vfs.ReadOptions{})
- if err != nil {
- t.Fatalf("fd.PRead failed: %v", err)
- }
- if n != int64(len(data)) {
- t.Errorf("fd.PRead got short read length %d, want %d", n, len(data))
- }
- if got, want := string(readBuf), string(data); got != want {
- t.Errorf("PRead got %q want %s", got, want)
- }
-
- })
- }
-}
-
-func TestLocks(t *testing.T) {
- ctx := contexttest.Context(t)
- fd, cleanup, err := newFileFD(ctx, 0644)
- if err != nil {
- t.Fatal(err)
- }
- defer cleanup()
-
- uid1 := 123
- uid2 := 456
- if err := fd.Impl().LockBSD(ctx, uid1, lock.ReadLock, nil); err != nil {
- t.Fatalf("fd.Impl().LockBSD failed: err = %v", err)
- }
- if err := fd.Impl().LockBSD(ctx, uid2, lock.ReadLock, nil); err != nil {
- t.Fatalf("fd.Impl().LockBSD failed: err = %v", err)
- }
- if got, want := fd.Impl().LockBSD(ctx, uid2, lock.WriteLock, nil), syserror.ErrWouldBlock; got != want {
- t.Fatalf("fd.Impl().LockBSD failed: got = %v, want = %v", got, want)
- }
- if err := fd.Impl().UnlockBSD(ctx, uid1); err != nil {
- t.Fatalf("fd.Impl().UnlockBSD failed: err = %v", err)
- }
- if err := fd.Impl().LockBSD(ctx, uid2, lock.WriteLock, nil); err != nil {
- t.Fatalf("fd.Impl().LockBSD failed: err = %v", err)
- }
-
- if err := fd.Impl().LockPOSIX(ctx, uid1, lock.ReadLock, 0, 1, linux.SEEK_SET, nil); err != nil {
- t.Fatalf("fd.Impl().LockPOSIX failed: err = %v", err)
- }
- if err := fd.Impl().LockPOSIX(ctx, uid2, lock.ReadLock, 1, 2, linux.SEEK_SET, nil); err != nil {
- t.Fatalf("fd.Impl().LockPOSIX failed: err = %v", err)
- }
- if err := fd.Impl().LockPOSIX(ctx, uid1, lock.WriteLock, 0, 1, linux.SEEK_SET, nil); err != nil {
- t.Fatalf("fd.Impl().LockPOSIX failed: err = %v", err)
- }
- if got, want := fd.Impl().LockPOSIX(ctx, uid2, lock.ReadLock, 0, 1, linux.SEEK_SET, nil), syserror.ErrWouldBlock; got != want {
- t.Fatalf("fd.Impl().LockPOSIX failed: got = %v, want = %v", got, want)
- }
- if err := fd.Impl().UnlockPOSIX(ctx, uid1, 0, 1, linux.SEEK_SET); err != nil {
- t.Fatalf("fd.Impl().UnlockPOSIX failed: err = %v", err)
- }
-}
-
-func TestPRead(t *testing.T) {
- ctx := contexttest.Context(t)
- fd, cleanup, err := newFileFD(ctx, 0644)
- if err != nil {
- t.Fatal(err)
- }
- defer cleanup()
-
- // Write 100 sequences of 'gVisor is awesome'.
- data := bytes.Repeat([]byte("gVisor is awsome"), 100)
- n, err := fd.Write(ctx, usermem.BytesIOSequence(data), vfs.WriteOptions{})
- if err != nil {
- t.Fatalf("fd.Write failed: %v", err)
- }
- if n != int64(len(data)) {
- t.Errorf("fd.Write got short write length %d, want %d", n, len(data))
- }
-
- // Read various sizes from various offsets.
- sizes := []int{0, 1, 2, 10, 20, 50, 100, 1000}
- offsets := []int{0, 1, 2, 10, 20, 50, 100, 1000, len(data) - 100, len(data) - 1, len(data), len(data) + 1}
-
- for _, size := range sizes {
- for _, offset := range offsets {
- name := fmt.Sprintf("PRead offset=%d size=%d", offset, size)
- t.Run(name, func(t *testing.T) {
- var (
- wantRead []byte
- wantErr error
- )
- if offset < len(data) {
- wantRead = data[offset:]
- } else if size > 0 {
- wantErr = io.EOF
- }
- if offset+size < len(data) {
- wantRead = wantRead[:size]
- }
- buf := make([]byte, size)
- n, err := fd.PRead(ctx, usermem.BytesIOSequence(buf), int64(offset), vfs.ReadOptions{})
- if err != wantErr {
- t.Errorf("fd.PRead got err %v want %v", err, wantErr)
- }
- if n != int64(len(wantRead)) {
- t.Errorf("fd.PRead got %d bytes want %d", n, len(wantRead))
- }
- if got := string(buf[:n]); got != string(wantRead) {
- t.Errorf("fd.PRead got %q want %q", got, string(wantRead))
- }
- })
- }
- }
-}
-
-func TestTruncate(t *testing.T) {
- ctx := contexttest.Context(t)
- fd, cleanup, err := newFileFD(ctx, 0644)
- if err != nil {
- t.Fatal(err)
- }
- defer cleanup()
-
- // Fill the file with some data.
- data := bytes.Repeat([]byte("gVisor is awsome"), 100)
- written, err := fd.Write(ctx, usermem.BytesIOSequence(data), vfs.WriteOptions{})
- if err != nil {
- t.Fatalf("fd.Write failed: %v", err)
- }
-
- // Size should be same as written.
- sizeStatOpts := vfs.StatOptions{Mask: linux.STATX_SIZE}
- stat, err := fd.Stat(ctx, sizeStatOpts)
- if err != nil {
- t.Fatalf("fd.Stat failed: %v", err)
- }
- if got, want := int64(stat.Size), written; got != want {
- t.Errorf("fd.Stat got size %d, want %d", got, want)
- }
-
- // Truncate down.
- newSize := uint64(10)
- if err := fd.SetStat(ctx, vfs.SetStatOptions{
- Stat: linux.Statx{
- Mask: linux.STATX_SIZE,
- Size: newSize,
- },
- }); err != nil {
- t.Errorf("fd.Truncate failed: %v", err)
- }
- // Size should be updated.
- statAfterTruncateDown, err := fd.Stat(ctx, sizeStatOpts)
- if err != nil {
- t.Fatalf("fd.Stat failed: %v", err)
- }
- if got, want := statAfterTruncateDown.Size, newSize; got != want {
- t.Errorf("fd.Stat got size %d, want %d", got, want)
- }
- // We should only read newSize worth of data.
- buf := make([]byte, 1000)
- if n, err := fd.PRead(ctx, usermem.BytesIOSequence(buf), 0, vfs.ReadOptions{}); err != nil && err != io.EOF {
- t.Fatalf("fd.PRead failed: %v", err)
- } else if uint64(n) != newSize {
- t.Errorf("fd.PRead got size %d, want %d", n, newSize)
- }
- // Mtime and Ctime should be bumped.
- if got := statAfterTruncateDown.Mtime.ToNsec(); got <= stat.Mtime.ToNsec() {
- t.Errorf("fd.Stat got Mtime %v, want > %v", got, stat.Mtime)
- }
- if got := statAfterTruncateDown.Ctime.ToNsec(); got <= stat.Ctime.ToNsec() {
- t.Errorf("fd.Stat got Ctime %v, want > %v", got, stat.Ctime)
- }
-
- // Truncate up.
- newSize = 100
- if err := fd.SetStat(ctx, vfs.SetStatOptions{
- Stat: linux.Statx{
- Mask: linux.STATX_SIZE,
- Size: newSize,
- },
- }); err != nil {
- t.Errorf("fd.Truncate failed: %v", err)
- }
- // Size should be updated.
- statAfterTruncateUp, err := fd.Stat(ctx, sizeStatOpts)
- if err != nil {
- t.Fatalf("fd.Stat failed: %v", err)
- }
- if got, want := statAfterTruncateUp.Size, newSize; got != want {
- t.Errorf("fd.Stat got size %d, want %d", got, want)
- }
- // We should read newSize worth of data.
- buf = make([]byte, 1000)
- if n, err := fd.PRead(ctx, usermem.BytesIOSequence(buf), 0, vfs.ReadOptions{}); err != nil && err != io.EOF {
- t.Fatalf("fd.PRead failed: %v", err)
- } else if uint64(n) != newSize {
- t.Errorf("fd.PRead got size %d, want %d", n, newSize)
- }
- // Bytes should be null after 10, since we previously truncated to 10.
- for i := uint64(10); i < newSize; i++ {
- if buf[i] != 0 {
- t.Errorf("fd.PRead got byte %d=%x, want 0", i, buf[i])
- break
- }
- }
- // Mtime and Ctime should be bumped.
- if got := statAfterTruncateUp.Mtime.ToNsec(); got <= statAfterTruncateDown.Mtime.ToNsec() {
- t.Errorf("fd.Stat got Mtime %v, want > %v", got, statAfterTruncateDown.Mtime)
- }
- if got := statAfterTruncateUp.Ctime.ToNsec(); got <= statAfterTruncateDown.Ctime.ToNsec() {
- t.Errorf("fd.Stat got Ctime %v, want > %v", got, stat.Ctime)
- }
-
- // Truncate to the current size.
- newSize = statAfterTruncateUp.Size
- if err := fd.SetStat(ctx, vfs.SetStatOptions{
- Stat: linux.Statx{
- Mask: linux.STATX_SIZE,
- Size: newSize,
- },
- }); err != nil {
- t.Errorf("fd.Truncate failed: %v", err)
- }
- statAfterTruncateNoop, err := fd.Stat(ctx, sizeStatOpts)
- if err != nil {
- t.Fatalf("fd.Stat failed: %v", err)
- }
- // Mtime and Ctime should not be bumped, since operation is a noop.
- if got := statAfterTruncateNoop.Mtime.ToNsec(); got != statAfterTruncateUp.Mtime.ToNsec() {
- t.Errorf("fd.Stat got Mtime %v, want %v", got, statAfterTruncateUp.Mtime)
- }
- if got := statAfterTruncateNoop.Ctime.ToNsec(); got != statAfterTruncateUp.Ctime.ToNsec() {
- t.Errorf("fd.Stat got Ctime %v, want %v", got, statAfterTruncateUp.Ctime)
- }
-}
diff --git a/pkg/sentry/fsimpl/tmpfs/stat_test.go b/pkg/sentry/fsimpl/tmpfs/stat_test.go
deleted file mode 100644
index f7ee4aab2..000000000
--- a/pkg/sentry/fsimpl/tmpfs/stat_test.go
+++ /dev/null
@@ -1,236 +0,0 @@
-// Copyright 2020 The gVisor Authors.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package tmpfs
-
-import (
- "fmt"
- "testing"
-
- "gvisor.dev/gvisor/pkg/abi/linux"
- "gvisor.dev/gvisor/pkg/sentry/contexttest"
- "gvisor.dev/gvisor/pkg/sentry/kernel/auth"
- "gvisor.dev/gvisor/pkg/sentry/vfs"
-)
-
-func TestStatAfterCreate(t *testing.T) {
- ctx := contexttest.Context(t)
- mode := linux.FileMode(0644)
-
- // Run with different file types.
- for _, typ := range []string{"file", "dir", "pipe"} {
- t.Run(fmt.Sprintf("type=%q", typ), func(t *testing.T) {
- var (
- fd *vfs.FileDescription
- cleanup func()
- err error
- )
- switch typ {
- case "file":
- fd, cleanup, err = newFileFD(ctx, mode)
- case "dir":
- fd, cleanup, err = newDirFD(ctx, mode)
- case "pipe":
- fd, cleanup, err = newPipeFD(ctx, mode)
- default:
- panic(fmt.Sprintf("unknown typ %q", typ))
- }
- if err != nil {
- t.Fatal(err)
- }
- defer cleanup()
-
- got, err := fd.Stat(ctx, vfs.StatOptions{})
- if err != nil {
- t.Fatalf("Stat failed: %v", err)
- }
-
- // Atime, Ctime, Mtime should all be current time (non-zero).
- atime, ctime, mtime := got.Atime.ToNsec(), got.Ctime.ToNsec(), got.Mtime.ToNsec()
- if atime != ctime || ctime != mtime {
- t.Errorf("got atime=%d ctime=%d mtime=%d, wanted equal values", atime, ctime, mtime)
- }
- if atime == 0 {
- t.Errorf("got atime=%d, want non-zero", atime)
- }
-
- // Btime should be 0, as it is not set by tmpfs.
- if btime := got.Btime.ToNsec(); btime != 0 {
- t.Errorf("got btime %d, want 0", got.Btime.ToNsec())
- }
-
- // Size should be 0 (except for directories, which make up a size
- // of 20 per entry, including the "." and ".." entries present in
- // otherwise-empty directories).
- wantSize := uint64(0)
- if typ == "dir" {
- wantSize = 40
- }
- if got.Size != wantSize {
- t.Errorf("got size %d, want %d", got.Size, wantSize)
- }
-
- // Nlink should be 1 for files, 2 for dirs.
- wantNlink := uint32(1)
- if typ == "dir" {
- wantNlink = 2
- }
- if got.Nlink != wantNlink {
- t.Errorf("got nlink %d, want %d", got.Nlink, wantNlink)
- }
-
- // UID and GID are set from context creds.
- creds := auth.CredentialsFromContext(ctx)
- if got.UID != uint32(creds.EffectiveKUID) {
- t.Errorf("got uid %d, want %d", got.UID, uint32(creds.EffectiveKUID))
- }
- if got.GID != uint32(creds.EffectiveKGID) {
- t.Errorf("got gid %d, want %d", got.GID, uint32(creds.EffectiveKGID))
- }
-
- // Mode.
- wantMode := uint16(mode)
- switch typ {
- case "file":
- wantMode |= linux.S_IFREG
- case "dir":
- wantMode |= linux.S_IFDIR
- case "pipe":
- wantMode |= linux.S_IFIFO
- default:
- panic(fmt.Sprintf("unknown typ %q", typ))
- }
-
- if got.Mode != wantMode {
- t.Errorf("got mode %x, want %x", got.Mode, wantMode)
- }
-
- // Ino.
- if got.Ino == 0 {
- t.Errorf("got ino %d, want not 0", got.Ino)
- }
- })
- }
-}
-
-func TestSetStatAtime(t *testing.T) {
- ctx := contexttest.Context(t)
- fd, cleanup, err := newFileFD(ctx, 0644)
- if err != nil {
- t.Fatal(err)
- }
- defer cleanup()
-
- allStatOptions := vfs.StatOptions{Mask: linux.STATX_ALL}
-
- // Get initial stat.
- initialStat, err := fd.Stat(ctx, allStatOptions)
- if err != nil {
- t.Fatalf("Stat failed: %v", err)
- }
-
- // Set atime, but without the mask.
- if err := fd.SetStat(ctx, vfs.SetStatOptions{Stat: linux.Statx{
- Mask: 0,
- Atime: linux.NsecToStatxTimestamp(100),
- }}); err != nil {
- t.Errorf("SetStat atime without mask failed: %v", err)
- }
- // Atime should be unchanged.
- if gotStat, err := fd.Stat(ctx, allStatOptions); err != nil {
- t.Errorf("Stat got error: %v", err)
- } else if gotStat.Atime != initialStat.Atime {
- t.Errorf("Stat got atime %d, want %d", gotStat.Atime, initialStat.Atime)
- }
-
- // Set atime, this time included in the mask.
- setStat := linux.Statx{
- Mask: linux.STATX_ATIME,
- Atime: linux.NsecToStatxTimestamp(100),
- }
- if err := fd.SetStat(ctx, vfs.SetStatOptions{Stat: setStat}); err != nil {
- t.Errorf("SetStat atime with mask failed: %v", err)
- }
- if gotStat, err := fd.Stat(ctx, allStatOptions); err != nil {
- t.Errorf("Stat got error: %v", err)
- } else if gotStat.Atime != setStat.Atime {
- t.Errorf("Stat got atime %d, want %d", gotStat.Atime, setStat.Atime)
- }
-}
-
-func TestSetStat(t *testing.T) {
- ctx := contexttest.Context(t)
- mode := linux.FileMode(0644)
-
- // Run with different file types.
- for _, typ := range []string{"file", "dir", "pipe"} {
- t.Run(fmt.Sprintf("type=%q", typ), func(t *testing.T) {
- var (
- fd *vfs.FileDescription
- cleanup func()
- err error
- )
- switch typ {
- case "file":
- fd, cleanup, err = newFileFD(ctx, mode)
- case "dir":
- fd, cleanup, err = newDirFD(ctx, mode)
- case "pipe":
- fd, cleanup, err = newPipeFD(ctx, mode)
- default:
- panic(fmt.Sprintf("unknown typ %q", typ))
- }
- if err != nil {
- t.Fatal(err)
- }
- defer cleanup()
-
- allStatOptions := vfs.StatOptions{Mask: linux.STATX_ALL}
-
- // Get initial stat.
- initialStat, err := fd.Stat(ctx, allStatOptions)
- if err != nil {
- t.Fatalf("Stat failed: %v", err)
- }
-
- // Set atime, but without the mask.
- if err := fd.SetStat(ctx, vfs.SetStatOptions{Stat: linux.Statx{
- Mask: 0,
- Atime: linux.NsecToStatxTimestamp(100),
- }}); err != nil {
- t.Errorf("SetStat atime without mask failed: %v", err)
- }
- // Atime should be unchanged.
- if gotStat, err := fd.Stat(ctx, allStatOptions); err != nil {
- t.Errorf("Stat got error: %v", err)
- } else if gotStat.Atime != initialStat.Atime {
- t.Errorf("Stat got atime %d, want %d", gotStat.Atime, initialStat.Atime)
- }
-
- // Set atime, this time included in the mask.
- setStat := linux.Statx{
- Mask: linux.STATX_ATIME,
- Atime: linux.NsecToStatxTimestamp(100),
- }
- if err := fd.SetStat(ctx, vfs.SetStatOptions{Stat: setStat}); err != nil {
- t.Errorf("SetStat atime with mask failed: %v", err)
- }
- if gotStat, err := fd.Stat(ctx, allStatOptions); err != nil {
- t.Errorf("Stat got error: %v", err)
- } else if gotStat.Atime != setStat.Atime {
- t.Errorf("Stat got atime %d, want %d", gotStat.Atime, setStat.Atime)
- }
- })
- }
-}
diff --git a/pkg/sentry/fsimpl/tmpfs/tmpfs_state_autogen.go b/pkg/sentry/fsimpl/tmpfs/tmpfs_state_autogen.go
new file mode 100644
index 000000000..d88136656
--- /dev/null
+++ b/pkg/sentry/fsimpl/tmpfs/tmpfs_state_autogen.go
@@ -0,0 +1,88 @@
+// automatically generated by stateify.
+
+package tmpfs
+
+import (
+ "gvisor.dev/gvisor/pkg/state"
+)
+
+func (x *dentryList) StateTypeName() string {
+ return "pkg/sentry/fsimpl/tmpfs.dentryList"
+}
+
+func (x *dentryList) StateFields() []string {
+ return []string{
+ "head",
+ "tail",
+ }
+}
+
+func (x *dentryList) beforeSave() {}
+
+func (x *dentryList) StateSave(m state.Sink) {
+ x.beforeSave()
+ m.Save(0, &x.head)
+ m.Save(1, &x.tail)
+}
+
+func (x *dentryList) afterLoad() {}
+
+func (x *dentryList) StateLoad(m state.Source) {
+ m.Load(0, &x.head)
+ m.Load(1, &x.tail)
+}
+
+func (x *dentryEntry) StateTypeName() string {
+ return "pkg/sentry/fsimpl/tmpfs.dentryEntry"
+}
+
+func (x *dentryEntry) StateFields() []string {
+ return []string{
+ "next",
+ "prev",
+ }
+}
+
+func (x *dentryEntry) beforeSave() {}
+
+func (x *dentryEntry) StateSave(m state.Sink) {
+ x.beforeSave()
+ m.Save(0, &x.next)
+ m.Save(1, &x.prev)
+}
+
+func (x *dentryEntry) afterLoad() {}
+
+func (x *dentryEntry) StateLoad(m state.Source) {
+ m.Load(0, &x.next)
+ m.Load(1, &x.prev)
+}
+
+func (x *inodeRefs) StateTypeName() string {
+ return "pkg/sentry/fsimpl/tmpfs.inodeRefs"
+}
+
+func (x *inodeRefs) StateFields() []string {
+ return []string{
+ "refCount",
+ }
+}
+
+func (x *inodeRefs) beforeSave() {}
+
+func (x *inodeRefs) StateSave(m state.Sink) {
+ x.beforeSave()
+ m.Save(0, &x.refCount)
+}
+
+func (x *inodeRefs) afterLoad() {}
+
+func (x *inodeRefs) StateLoad(m state.Source) {
+ m.Load(0, &x.refCount)
+}
+
+func init() {
+ state.Register((*dentryList)(nil))
+ state.Register((*dentryEntry)(nil))
+ state.Register((*inodeRefs)(nil))
+}
diff --git a/pkg/sentry/fsimpl/tmpfs/tmpfs_test.go b/pkg/sentry/fsimpl/tmpfs/tmpfs_test.go
deleted file mode 100644
index 6f3e3ae6f..000000000
--- a/pkg/sentry/fsimpl/tmpfs/tmpfs_test.go
+++ /dev/null
@@ -1,156 +0,0 @@
-// Copyright 2019 The gVisor Authors.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package tmpfs
-
-import (
- "fmt"
- "sync/atomic"
-
- "gvisor.dev/gvisor/pkg/abi/linux"
- "gvisor.dev/gvisor/pkg/context"
- "gvisor.dev/gvisor/pkg/fspath"
- "gvisor.dev/gvisor/pkg/sentry/kernel/auth"
- "gvisor.dev/gvisor/pkg/sentry/vfs"
-)
-
-// nextFileID is used to generate unique file names.
-var nextFileID int64
-
-// newTmpfsRoot creates a new tmpfs mount, and returns the root. If the error
-// is not nil, then cleanup should be called when the root is no longer needed.
-func newTmpfsRoot(ctx context.Context) (*vfs.VirtualFilesystem, vfs.VirtualDentry, func(), error) {
- creds := auth.CredentialsFromContext(ctx)
-
- vfsObj := &vfs.VirtualFilesystem{}
- if err := vfsObj.Init(ctx); err != nil {
- return nil, vfs.VirtualDentry{}, nil, fmt.Errorf("VFS init: %v", err)
- }
-
- vfsObj.MustRegisterFilesystemType("tmpfs", FilesystemType{}, &vfs.RegisterFilesystemTypeOptions{
- AllowUserMount: true,
- })
- mntns, err := vfsObj.NewMountNamespace(ctx, creds, "", "tmpfs", &vfs.GetFilesystemOptions{})
- if err != nil {
- return nil, vfs.VirtualDentry{}, nil, fmt.Errorf("failed to create tmpfs root mount: %v", err)
- }
- root := mntns.Root()
- return vfsObj, root, func() {
- root.DecRef(ctx)
- mntns.DecRef(ctx)
- }, nil
-}
-
-// newFileFD creates a new file in a new tmpfs mount, and returns the FD. If
-// the returned err is not nil, then cleanup should be called when the FD is no
-// longer needed.
-func newFileFD(ctx context.Context, mode linux.FileMode) (*vfs.FileDescription, func(), error) {
- creds := auth.CredentialsFromContext(ctx)
- vfsObj, root, cleanup, err := newTmpfsRoot(ctx)
- if err != nil {
- return nil, nil, err
- }
-
- filename := fmt.Sprintf("tmpfs-test-file-%d", atomic.AddInt64(&nextFileID, 1))
-
- // Create the file that will be write/read.
- fd, err := vfsObj.OpenAt(ctx, creds, &vfs.PathOperation{
- Root: root,
- Start: root,
- Path: fspath.Parse(filename),
- }, &vfs.OpenOptions{
- Flags: linux.O_RDWR | linux.O_CREAT | linux.O_EXCL,
- Mode: linux.ModeRegular | mode,
- })
- if err != nil {
- cleanup()
- return nil, nil, fmt.Errorf("failed to create file %q: %v", filename, err)
- }
-
- return fd, cleanup, nil
-}
-
-// newDirFD is like newFileFD, but for directories.
-func newDirFD(ctx context.Context, mode linux.FileMode) (*vfs.FileDescription, func(), error) {
- creds := auth.CredentialsFromContext(ctx)
- vfsObj, root, cleanup, err := newTmpfsRoot(ctx)
- if err != nil {
- return nil, nil, err
- }
-
- dirname := fmt.Sprintf("tmpfs-test-dir-%d", atomic.AddInt64(&nextFileID, 1))
-
- // Create the dir.
- if err := vfsObj.MkdirAt(ctx, creds, &vfs.PathOperation{
- Root: root,
- Start: root,
- Path: fspath.Parse(dirname),
- }, &vfs.MkdirOptions{
- Mode: linux.ModeDirectory | mode,
- }); err != nil {
- cleanup()
- return nil, nil, fmt.Errorf("failed to create directory %q: %v", dirname, err)
- }
-
- // Open the dir and return it.
- fd, err := vfsObj.OpenAt(ctx, creds, &vfs.PathOperation{
- Root: root,
- Start: root,
- Path: fspath.Parse(dirname),
- }, &vfs.OpenOptions{
- Flags: linux.O_RDONLY | linux.O_DIRECTORY,
- })
- if err != nil {
- cleanup()
- return nil, nil, fmt.Errorf("failed to open directory %q: %v", dirname, err)
- }
-
- return fd, cleanup, nil
-}
-
-// newPipeFD is like newFileFD, but for pipes.
-func newPipeFD(ctx context.Context, mode linux.FileMode) (*vfs.FileDescription, func(), error) {
- creds := auth.CredentialsFromContext(ctx)
- vfsObj, root, cleanup, err := newTmpfsRoot(ctx)
- if err != nil {
- return nil, nil, err
- }
-
- name := fmt.Sprintf("tmpfs-test-%d", atomic.AddInt64(&nextFileID, 1))
-
- if err := vfsObj.MknodAt(ctx, creds, &vfs.PathOperation{
- Root: root,
- Start: root,
- Path: fspath.Parse(name),
- }, &vfs.MknodOptions{
- Mode: linux.ModeNamedPipe | mode,
- }); err != nil {
- cleanup()
- return nil, nil, fmt.Errorf("failed to create pipe %q: %v", name, err)
- }
-
- fd, err := vfsObj.OpenAt(ctx, creds, &vfs.PathOperation{
- Root: root,
- Start: root,
- Path: fspath.Parse(name),
- }, &vfs.OpenOptions{
- Flags: linux.O_RDWR,
- })
- if err != nil {
- cleanup()
- return nil, nil, fmt.Errorf("failed to open pipe %q: %v", name, err)
- }
-
- return fd, cleanup, nil
-}