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-rw-r--r--pkg/sentry/fsimpl/kernfs/BUILD150
-rw-r--r--pkg/sentry/fsimpl/kernfs/dentry_list.go221
-rw-r--r--pkg/sentry/fsimpl/kernfs/fstree.go55
-rw-r--r--pkg/sentry/fsimpl/kernfs/kernfs_state_autogen.go965
-rw-r--r--pkg/sentry/fsimpl/kernfs/kernfs_test.go409
-rw-r--r--pkg/sentry/fsimpl/kernfs/slot_list.go221
-rw-r--r--pkg/sentry/fsimpl/kernfs/static_directory_refs.go140
-rw-r--r--pkg/sentry/fsimpl/kernfs/synthetic_directory_refs.go140
8 files changed, 1742 insertions, 559 deletions
diff --git a/pkg/sentry/fsimpl/kernfs/BUILD b/pkg/sentry/fsimpl/kernfs/BUILD
deleted file mode 100644
index 4b577ea43..000000000
--- a/pkg/sentry/fsimpl/kernfs/BUILD
+++ /dev/null
@@ -1,150 +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 = "kernfs",
- prefix = "dentry",
- template = "//pkg/ilist:generic_list",
- types = {
- "Element": "*Dentry",
- "Linker": "*Dentry",
- },
-)
-
-go_template_instance(
- name = "fstree",
- out = "fstree.go",
- package = "kernfs",
- prefix = "generic",
- template = "//pkg/sentry/vfs/genericfstree:generic_fstree",
- types = {
- "Dentry": "Dentry",
- },
-)
-
-go_template_instance(
- name = "slot_list",
- out = "slot_list.go",
- package = "kernfs",
- prefix = "slot",
- template = "//pkg/ilist:generic_list",
- types = {
- "Element": "*slot",
- "Linker": "*slot",
- },
-)
-
-go_template_instance(
- name = "static_directory_refs",
- out = "static_directory_refs.go",
- package = "kernfs",
- prefix = "StaticDirectory",
- template = "//pkg/refsvfs2:refs_template",
- types = {
- "T": "StaticDirectory",
- },
-)
-
-go_template_instance(
- name = "dir_refs",
- out = "dir_refs.go",
- package = "kernfs_test",
- prefix = "dir",
- template = "//pkg/refsvfs2:refs_template",
- types = {
- "T": "dir",
- },
-)
-
-go_template_instance(
- name = "readonly_dir_refs",
- out = "readonly_dir_refs.go",
- package = "kernfs_test",
- prefix = "readonlyDir",
- template = "//pkg/refsvfs2:refs_template",
- types = {
- "T": "readonlyDir",
- },
-)
-
-go_template_instance(
- name = "synthetic_directory_refs",
- out = "synthetic_directory_refs.go",
- package = "kernfs",
- prefix = "syntheticDirectory",
- template = "//pkg/refsvfs2:refs_template",
- types = {
- "T": "syntheticDirectory",
- },
-)
-
-go_library(
- name = "kernfs",
- srcs = [
- "dentry_list.go",
- "dynamic_bytes_file.go",
- "fd_impl_util.go",
- "filesystem.go",
- "fstree.go",
- "inode_impl_util.go",
- "kernfs.go",
- "mmap_util.go",
- "save_restore.go",
- "slot_list.go",
- "static_directory_refs.go",
- "symlink.go",
- "synthetic_directory.go",
- "synthetic_directory_refs.go",
- ],
- visibility = ["//pkg/sentry:internal"],
- deps = [
- "//pkg/abi/linux",
- "//pkg/context",
- "//pkg/errors/linuxerr",
- "//pkg/fspath",
- "//pkg/hostarch",
- "//pkg/log",
- "//pkg/refs",
- "//pkg/refsvfs2",
- "//pkg/safemem",
- "//pkg/sentry/fs/fsutil",
- "//pkg/sentry/fs/lock",
- "//pkg/sentry/kernel/auth",
- "//pkg/sentry/kernel/time",
- "//pkg/sentry/memmap",
- "//pkg/sentry/socket/unix/transport",
- "//pkg/sentry/vfs",
- "//pkg/sync",
- "//pkg/usermem",
- ],
-)
-
-go_test(
- name = "kernfs_test",
- size = "small",
- srcs = [
- "dir_refs.go",
- "kernfs_test.go",
- "readonly_dir_refs.go",
- ],
- deps = [
- ":kernfs",
- "//pkg/abi/linux",
- "//pkg/context",
- "//pkg/errors/linuxerr",
- "//pkg/fspath",
- "//pkg/log",
- "//pkg/refs",
- "//pkg/refsvfs2",
- "//pkg/sentry/contexttest",
- "//pkg/sentry/fsimpl/testutil",
- "//pkg/sentry/kernel/auth",
- "//pkg/sentry/vfs",
- "//pkg/usermem",
- "@com_github_google_go_cmp//cmp:go_default_library",
- ],
-)
diff --git a/pkg/sentry/fsimpl/kernfs/dentry_list.go b/pkg/sentry/fsimpl/kernfs/dentry_list.go
new file mode 100644
index 000000000..e73cde1f1
--- /dev/null
+++ b/pkg/sentry/fsimpl/kernfs/dentry_list.go
@@ -0,0 +1,221 @@
+package kernfs
+
+// 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.
+//
+//go:nosplit
+func (l *dentryList) Empty() bool {
+ return l.head == nil
+}
+
+// Front returns the first element of list l or nil.
+//
+//go:nosplit
+func (l *dentryList) Front() *Dentry {
+ return l.head
+}
+
+// Back returns the last element of list l or nil.
+//
+//go:nosplit
+func (l *dentryList) Back() *Dentry {
+ return l.tail
+}
+
+// Len returns the number of elements in the list.
+//
+// NOTE: This is an O(n) operation.
+//
+//go:nosplit
+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.
+//
+//go:nosplit
+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.
+//
+//go:nosplit
+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.
+//
+//go:nosplit
+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.
+//
+//go:nosplit
+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.
+//
+//go:nosplit
+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.
+//
+//go:nosplit
+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.
+//
+//go:nosplit
+func (e *dentryEntry) Next() *Dentry {
+ return e.next
+}
+
+// Prev returns the entry that precedes e in the list.
+//
+//go:nosplit
+func (e *dentryEntry) Prev() *Dentry {
+ return e.prev
+}
+
+// SetNext assigns 'entry' as the entry that follows e in the list.
+//
+//go:nosplit
+func (e *dentryEntry) SetNext(elem *Dentry) {
+ e.next = elem
+}
+
+// SetPrev assigns 'entry' as the entry that precedes e in the list.
+//
+//go:nosplit
+func (e *dentryEntry) SetPrev(elem *Dentry) {
+ e.prev = elem
+}
diff --git a/pkg/sentry/fsimpl/kernfs/fstree.go b/pkg/sentry/fsimpl/kernfs/fstree.go
new file mode 100644
index 000000000..9dc52dabc
--- /dev/null
+++ b/pkg/sentry/fsimpl/kernfs/fstree.go
@@ -0,0 +1,55 @@
+package kernfs
+
+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 mnt != nil && &d.vfsd == mnt.Root() {
+ return nil
+ }
+ if d.parent == nil {
+ return vfs.PrependPathAtNonMountRootError{}
+ }
+ b.PrependComponent(d.name)
+ d = d.parent
+ }
+}
+
+// DebugPathname returns a pathname to d relative to its filesystem root.
+// DebugPathname does not correspond to any Linux function; it's used to
+// generate dentry pathnames for debugging.
+func genericDebugPathname(d *Dentry) string {
+ var b fspath.Builder
+ _ = genericPrependPath(vfs.VirtualDentry{}, nil, d, &b)
+ return b.String()
+}
diff --git a/pkg/sentry/fsimpl/kernfs/kernfs_state_autogen.go b/pkg/sentry/fsimpl/kernfs/kernfs_state_autogen.go
new file mode 100644
index 000000000..f8add23f8
--- /dev/null
+++ b/pkg/sentry/fsimpl/kernfs/kernfs_state_autogen.go
@@ -0,0 +1,965 @@
+// automatically generated by stateify.
+
+package kernfs
+
+import (
+ "gvisor.dev/gvisor/pkg/state"
+)
+
+func (l *dentryList) StateTypeName() string {
+ return "pkg/sentry/fsimpl/kernfs.dentryList"
+}
+
+func (l *dentryList) StateFields() []string {
+ return []string{
+ "head",
+ "tail",
+ }
+}
+
+func (l *dentryList) beforeSave() {}
+
+// +checklocksignore
+func (l *dentryList) StateSave(stateSinkObject state.Sink) {
+ l.beforeSave()
+ stateSinkObject.Save(0, &l.head)
+ stateSinkObject.Save(1, &l.tail)
+}
+
+func (l *dentryList) afterLoad() {}
+
+// +checklocksignore
+func (l *dentryList) StateLoad(stateSourceObject state.Source) {
+ stateSourceObject.Load(0, &l.head)
+ stateSourceObject.Load(1, &l.tail)
+}
+
+func (e *dentryEntry) StateTypeName() string {
+ return "pkg/sentry/fsimpl/kernfs.dentryEntry"
+}
+
+func (e *dentryEntry) StateFields() []string {
+ return []string{
+ "next",
+ "prev",
+ }
+}
+
+func (e *dentryEntry) beforeSave() {}
+
+// +checklocksignore
+func (e *dentryEntry) StateSave(stateSinkObject state.Sink) {
+ e.beforeSave()
+ stateSinkObject.Save(0, &e.next)
+ stateSinkObject.Save(1, &e.prev)
+}
+
+func (e *dentryEntry) afterLoad() {}
+
+// +checklocksignore
+func (e *dentryEntry) StateLoad(stateSourceObject state.Source) {
+ stateSourceObject.Load(0, &e.next)
+ stateSourceObject.Load(1, &e.prev)
+}
+
+func (f *DynamicBytesFile) StateTypeName() string {
+ return "pkg/sentry/fsimpl/kernfs.DynamicBytesFile"
+}
+
+func (f *DynamicBytesFile) StateFields() []string {
+ return []string{
+ "InodeAttrs",
+ "InodeNoStatFS",
+ "InodeNoopRefCount",
+ "InodeNotDirectory",
+ "InodeNotSymlink",
+ "locks",
+ "data",
+ }
+}
+
+func (f *DynamicBytesFile) beforeSave() {}
+
+// +checklocksignore
+func (f *DynamicBytesFile) StateSave(stateSinkObject state.Sink) {
+ f.beforeSave()
+ stateSinkObject.Save(0, &f.InodeAttrs)
+ stateSinkObject.Save(1, &f.InodeNoStatFS)
+ stateSinkObject.Save(2, &f.InodeNoopRefCount)
+ stateSinkObject.Save(3, &f.InodeNotDirectory)
+ stateSinkObject.Save(4, &f.InodeNotSymlink)
+ stateSinkObject.Save(5, &f.locks)
+ stateSinkObject.Save(6, &f.data)
+}
+
+func (f *DynamicBytesFile) afterLoad() {}
+
+// +checklocksignore
+func (f *DynamicBytesFile) StateLoad(stateSourceObject state.Source) {
+ stateSourceObject.Load(0, &f.InodeAttrs)
+ stateSourceObject.Load(1, &f.InodeNoStatFS)
+ stateSourceObject.Load(2, &f.InodeNoopRefCount)
+ stateSourceObject.Load(3, &f.InodeNotDirectory)
+ stateSourceObject.Load(4, &f.InodeNotSymlink)
+ stateSourceObject.Load(5, &f.locks)
+ stateSourceObject.Load(6, &f.data)
+}
+
+func (fd *DynamicBytesFD) StateTypeName() string {
+ return "pkg/sentry/fsimpl/kernfs.DynamicBytesFD"
+}
+
+func (fd *DynamicBytesFD) StateFields() []string {
+ return []string{
+ "FileDescriptionDefaultImpl",
+ "DynamicBytesFileDescriptionImpl",
+ "LockFD",
+ "vfsfd",
+ "inode",
+ }
+}
+
+func (fd *DynamicBytesFD) beforeSave() {}
+
+// +checklocksignore
+func (fd *DynamicBytesFD) StateSave(stateSinkObject state.Sink) {
+ fd.beforeSave()
+ stateSinkObject.Save(0, &fd.FileDescriptionDefaultImpl)
+ stateSinkObject.Save(1, &fd.DynamicBytesFileDescriptionImpl)
+ stateSinkObject.Save(2, &fd.LockFD)
+ stateSinkObject.Save(3, &fd.vfsfd)
+ stateSinkObject.Save(4, &fd.inode)
+}
+
+func (fd *DynamicBytesFD) afterLoad() {}
+
+// +checklocksignore
+func (fd *DynamicBytesFD) StateLoad(stateSourceObject state.Source) {
+ stateSourceObject.Load(0, &fd.FileDescriptionDefaultImpl)
+ stateSourceObject.Load(1, &fd.DynamicBytesFileDescriptionImpl)
+ stateSourceObject.Load(2, &fd.LockFD)
+ stateSourceObject.Load(3, &fd.vfsfd)
+ stateSourceObject.Load(4, &fd.inode)
+}
+
+func (s *SeekEndConfig) StateTypeName() string {
+ return "pkg/sentry/fsimpl/kernfs.SeekEndConfig"
+}
+
+func (s *SeekEndConfig) StateFields() []string {
+ return nil
+}
+
+func (g *GenericDirectoryFDOptions) StateTypeName() string {
+ return "pkg/sentry/fsimpl/kernfs.GenericDirectoryFDOptions"
+}
+
+func (g *GenericDirectoryFDOptions) StateFields() []string {
+ return []string{
+ "SeekEnd",
+ }
+}
+
+func (g *GenericDirectoryFDOptions) beforeSave() {}
+
+// +checklocksignore
+func (g *GenericDirectoryFDOptions) StateSave(stateSinkObject state.Sink) {
+ g.beforeSave()
+ stateSinkObject.Save(0, &g.SeekEnd)
+}
+
+func (g *GenericDirectoryFDOptions) afterLoad() {}
+
+// +checklocksignore
+func (g *GenericDirectoryFDOptions) StateLoad(stateSourceObject state.Source) {
+ stateSourceObject.Load(0, &g.SeekEnd)
+}
+
+func (fd *GenericDirectoryFD) StateTypeName() string {
+ return "pkg/sentry/fsimpl/kernfs.GenericDirectoryFD"
+}
+
+func (fd *GenericDirectoryFD) StateFields() []string {
+ return []string{
+ "FileDescriptionDefaultImpl",
+ "DirectoryFileDescriptionDefaultImpl",
+ "LockFD",
+ "seekEnd",
+ "vfsfd",
+ "children",
+ "off",
+ }
+}
+
+func (fd *GenericDirectoryFD) beforeSave() {}
+
+// +checklocksignore
+func (fd *GenericDirectoryFD) StateSave(stateSinkObject state.Sink) {
+ fd.beforeSave()
+ stateSinkObject.Save(0, &fd.FileDescriptionDefaultImpl)
+ stateSinkObject.Save(1, &fd.DirectoryFileDescriptionDefaultImpl)
+ stateSinkObject.Save(2, &fd.LockFD)
+ stateSinkObject.Save(3, &fd.seekEnd)
+ stateSinkObject.Save(4, &fd.vfsfd)
+ stateSinkObject.Save(5, &fd.children)
+ stateSinkObject.Save(6, &fd.off)
+}
+
+func (fd *GenericDirectoryFD) afterLoad() {}
+
+// +checklocksignore
+func (fd *GenericDirectoryFD) StateLoad(stateSourceObject state.Source) {
+ stateSourceObject.Load(0, &fd.FileDescriptionDefaultImpl)
+ stateSourceObject.Load(1, &fd.DirectoryFileDescriptionDefaultImpl)
+ stateSourceObject.Load(2, &fd.LockFD)
+ stateSourceObject.Load(3, &fd.seekEnd)
+ stateSourceObject.Load(4, &fd.vfsfd)
+ stateSourceObject.Load(5, &fd.children)
+ stateSourceObject.Load(6, &fd.off)
+}
+
+func (i *InodeNoopRefCount) StateTypeName() string {
+ return "pkg/sentry/fsimpl/kernfs.InodeNoopRefCount"
+}
+
+func (i *InodeNoopRefCount) StateFields() []string {
+ return []string{
+ "InodeTemporary",
+ }
+}
+
+func (i *InodeNoopRefCount) beforeSave() {}
+
+// +checklocksignore
+func (i *InodeNoopRefCount) StateSave(stateSinkObject state.Sink) {
+ i.beforeSave()
+ stateSinkObject.Save(0, &i.InodeTemporary)
+}
+
+func (i *InodeNoopRefCount) afterLoad() {}
+
+// +checklocksignore
+func (i *InodeNoopRefCount) StateLoad(stateSourceObject state.Source) {
+ stateSourceObject.Load(0, &i.InodeTemporary)
+}
+
+func (i *InodeDirectoryNoNewChildren) StateTypeName() string {
+ return "pkg/sentry/fsimpl/kernfs.InodeDirectoryNoNewChildren"
+}
+
+func (i *InodeDirectoryNoNewChildren) StateFields() []string {
+ return []string{}
+}
+
+func (i *InodeDirectoryNoNewChildren) beforeSave() {}
+
+// +checklocksignore
+func (i *InodeDirectoryNoNewChildren) StateSave(stateSinkObject state.Sink) {
+ i.beforeSave()
+}
+
+func (i *InodeDirectoryNoNewChildren) afterLoad() {}
+
+// +checklocksignore
+func (i *InodeDirectoryNoNewChildren) StateLoad(stateSourceObject state.Source) {
+}
+
+func (i *InodeNotDirectory) StateTypeName() string {
+ return "pkg/sentry/fsimpl/kernfs.InodeNotDirectory"
+}
+
+func (i *InodeNotDirectory) StateFields() []string {
+ return []string{
+ "InodeAlwaysValid",
+ }
+}
+
+func (i *InodeNotDirectory) beforeSave() {}
+
+// +checklocksignore
+func (i *InodeNotDirectory) StateSave(stateSinkObject state.Sink) {
+ i.beforeSave()
+ stateSinkObject.Save(0, &i.InodeAlwaysValid)
+}
+
+func (i *InodeNotDirectory) afterLoad() {}
+
+// +checklocksignore
+func (i *InodeNotDirectory) StateLoad(stateSourceObject state.Source) {
+ stateSourceObject.Load(0, &i.InodeAlwaysValid)
+}
+
+func (i *InodeNotSymlink) StateTypeName() string {
+ return "pkg/sentry/fsimpl/kernfs.InodeNotSymlink"
+}
+
+func (i *InodeNotSymlink) StateFields() []string {
+ return []string{}
+}
+
+func (i *InodeNotSymlink) beforeSave() {}
+
+// +checklocksignore
+func (i *InodeNotSymlink) StateSave(stateSinkObject state.Sink) {
+ i.beforeSave()
+}
+
+func (i *InodeNotSymlink) afterLoad() {}
+
+// +checklocksignore
+func (i *InodeNotSymlink) StateLoad(stateSourceObject state.Source) {
+}
+
+func (a *InodeAttrs) StateTypeName() string {
+ return "pkg/sentry/fsimpl/kernfs.InodeAttrs"
+}
+
+func (a *InodeAttrs) StateFields() []string {
+ return []string{
+ "devMajor",
+ "devMinor",
+ "ino",
+ "mode",
+ "uid",
+ "gid",
+ "nlink",
+ "blockSize",
+ "atime",
+ "mtime",
+ "ctime",
+ }
+}
+
+func (a *InodeAttrs) beforeSave() {}
+
+// +checklocksignore
+func (a *InodeAttrs) StateSave(stateSinkObject state.Sink) {
+ a.beforeSave()
+ stateSinkObject.Save(0, &a.devMajor)
+ stateSinkObject.Save(1, &a.devMinor)
+ stateSinkObject.Save(2, &a.ino)
+ stateSinkObject.Save(3, &a.mode)
+ stateSinkObject.Save(4, &a.uid)
+ stateSinkObject.Save(5, &a.gid)
+ stateSinkObject.Save(6, &a.nlink)
+ stateSinkObject.Save(7, &a.blockSize)
+ stateSinkObject.Save(8, &a.atime)
+ stateSinkObject.Save(9, &a.mtime)
+ stateSinkObject.Save(10, &a.ctime)
+}
+
+func (a *InodeAttrs) afterLoad() {}
+
+// +checklocksignore
+func (a *InodeAttrs) StateLoad(stateSourceObject state.Source) {
+ stateSourceObject.Load(0, &a.devMajor)
+ stateSourceObject.Load(1, &a.devMinor)
+ stateSourceObject.Load(2, &a.ino)
+ stateSourceObject.Load(3, &a.mode)
+ stateSourceObject.Load(4, &a.uid)
+ stateSourceObject.Load(5, &a.gid)
+ stateSourceObject.Load(6, &a.nlink)
+ stateSourceObject.Load(7, &a.blockSize)
+ stateSourceObject.Load(8, &a.atime)
+ stateSourceObject.Load(9, &a.mtime)
+ stateSourceObject.Load(10, &a.ctime)
+}
+
+func (s *slot) StateTypeName() string {
+ return "pkg/sentry/fsimpl/kernfs.slot"
+}
+
+func (s *slot) StateFields() []string {
+ return []string{
+ "name",
+ "inode",
+ "static",
+ "slotEntry",
+ }
+}
+
+func (s *slot) beforeSave() {}
+
+// +checklocksignore
+func (s *slot) StateSave(stateSinkObject state.Sink) {
+ s.beforeSave()
+ stateSinkObject.Save(0, &s.name)
+ stateSinkObject.Save(1, &s.inode)
+ stateSinkObject.Save(2, &s.static)
+ stateSinkObject.Save(3, &s.slotEntry)
+}
+
+func (s *slot) afterLoad() {}
+
+// +checklocksignore
+func (s *slot) StateLoad(stateSourceObject state.Source) {
+ stateSourceObject.Load(0, &s.name)
+ stateSourceObject.Load(1, &s.inode)
+ stateSourceObject.Load(2, &s.static)
+ stateSourceObject.Load(3, &s.slotEntry)
+}
+
+func (o *OrderedChildrenOptions) StateTypeName() string {
+ return "pkg/sentry/fsimpl/kernfs.OrderedChildrenOptions"
+}
+
+func (o *OrderedChildrenOptions) StateFields() []string {
+ return []string{
+ "Writable",
+ }
+}
+
+func (o *OrderedChildrenOptions) beforeSave() {}
+
+// +checklocksignore
+func (o *OrderedChildrenOptions) StateSave(stateSinkObject state.Sink) {
+ o.beforeSave()
+ stateSinkObject.Save(0, &o.Writable)
+}
+
+func (o *OrderedChildrenOptions) afterLoad() {}
+
+// +checklocksignore
+func (o *OrderedChildrenOptions) StateLoad(stateSourceObject state.Source) {
+ stateSourceObject.Load(0, &o.Writable)
+}
+
+func (o *OrderedChildren) StateTypeName() string {
+ return "pkg/sentry/fsimpl/kernfs.OrderedChildren"
+}
+
+func (o *OrderedChildren) StateFields() []string {
+ return []string{
+ "writable",
+ "order",
+ "set",
+ }
+}
+
+func (o *OrderedChildren) beforeSave() {}
+
+// +checklocksignore
+func (o *OrderedChildren) StateSave(stateSinkObject state.Sink) {
+ o.beforeSave()
+ stateSinkObject.Save(0, &o.writable)
+ stateSinkObject.Save(1, &o.order)
+ stateSinkObject.Save(2, &o.set)
+}
+
+func (o *OrderedChildren) afterLoad() {}
+
+// +checklocksignore
+func (o *OrderedChildren) StateLoad(stateSourceObject state.Source) {
+ stateSourceObject.Load(0, &o.writable)
+ stateSourceObject.Load(1, &o.order)
+ stateSourceObject.Load(2, &o.set)
+}
+
+func (i *InodeSymlink) StateTypeName() string {
+ return "pkg/sentry/fsimpl/kernfs.InodeSymlink"
+}
+
+func (i *InodeSymlink) StateFields() []string {
+ return []string{
+ "InodeNotDirectory",
+ }
+}
+
+func (i *InodeSymlink) beforeSave() {}
+
+// +checklocksignore
+func (i *InodeSymlink) StateSave(stateSinkObject state.Sink) {
+ i.beforeSave()
+ stateSinkObject.Save(0, &i.InodeNotDirectory)
+}
+
+func (i *InodeSymlink) afterLoad() {}
+
+// +checklocksignore
+func (i *InodeSymlink) StateLoad(stateSourceObject state.Source) {
+ stateSourceObject.Load(0, &i.InodeNotDirectory)
+}
+
+func (s *StaticDirectory) StateTypeName() string {
+ return "pkg/sentry/fsimpl/kernfs.StaticDirectory"
+}
+
+func (s *StaticDirectory) StateFields() []string {
+ return []string{
+ "InodeAlwaysValid",
+ "InodeAttrs",
+ "InodeDirectoryNoNewChildren",
+ "InodeNoStatFS",
+ "InodeNotSymlink",
+ "InodeTemporary",
+ "OrderedChildren",
+ "StaticDirectoryRefs",
+ "locks",
+ "fdOpts",
+ }
+}
+
+func (s *StaticDirectory) beforeSave() {}
+
+// +checklocksignore
+func (s *StaticDirectory) StateSave(stateSinkObject state.Sink) {
+ s.beforeSave()
+ stateSinkObject.Save(0, &s.InodeAlwaysValid)
+ stateSinkObject.Save(1, &s.InodeAttrs)
+ stateSinkObject.Save(2, &s.InodeDirectoryNoNewChildren)
+ stateSinkObject.Save(3, &s.InodeNoStatFS)
+ stateSinkObject.Save(4, &s.InodeNotSymlink)
+ stateSinkObject.Save(5, &s.InodeTemporary)
+ stateSinkObject.Save(6, &s.OrderedChildren)
+ stateSinkObject.Save(7, &s.StaticDirectoryRefs)
+ stateSinkObject.Save(8, &s.locks)
+ stateSinkObject.Save(9, &s.fdOpts)
+}
+
+func (s *StaticDirectory) afterLoad() {}
+
+// +checklocksignore
+func (s *StaticDirectory) StateLoad(stateSourceObject state.Source) {
+ stateSourceObject.Load(0, &s.InodeAlwaysValid)
+ stateSourceObject.Load(1, &s.InodeAttrs)
+ stateSourceObject.Load(2, &s.InodeDirectoryNoNewChildren)
+ stateSourceObject.Load(3, &s.InodeNoStatFS)
+ stateSourceObject.Load(4, &s.InodeNotSymlink)
+ stateSourceObject.Load(5, &s.InodeTemporary)
+ stateSourceObject.Load(6, &s.OrderedChildren)
+ stateSourceObject.Load(7, &s.StaticDirectoryRefs)
+ stateSourceObject.Load(8, &s.locks)
+ stateSourceObject.Load(9, &s.fdOpts)
+}
+
+func (i *InodeAlwaysValid) StateTypeName() string {
+ return "pkg/sentry/fsimpl/kernfs.InodeAlwaysValid"
+}
+
+func (i *InodeAlwaysValid) StateFields() []string {
+ return []string{}
+}
+
+func (i *InodeAlwaysValid) beforeSave() {}
+
+// +checklocksignore
+func (i *InodeAlwaysValid) StateSave(stateSinkObject state.Sink) {
+ i.beforeSave()
+}
+
+func (i *InodeAlwaysValid) afterLoad() {}
+
+// +checklocksignore
+func (i *InodeAlwaysValid) StateLoad(stateSourceObject state.Source) {
+}
+
+func (i *InodeTemporary) StateTypeName() string {
+ return "pkg/sentry/fsimpl/kernfs.InodeTemporary"
+}
+
+func (i *InodeTemporary) StateFields() []string {
+ return []string{}
+}
+
+func (i *InodeTemporary) beforeSave() {}
+
+// +checklocksignore
+func (i *InodeTemporary) StateSave(stateSinkObject state.Sink) {
+ i.beforeSave()
+}
+
+func (i *InodeTemporary) afterLoad() {}
+
+// +checklocksignore
+func (i *InodeTemporary) StateLoad(stateSourceObject state.Source) {
+}
+
+func (i *InodeNoStatFS) StateTypeName() string {
+ return "pkg/sentry/fsimpl/kernfs.InodeNoStatFS"
+}
+
+func (i *InodeNoStatFS) StateFields() []string {
+ return []string{}
+}
+
+func (i *InodeNoStatFS) beforeSave() {}
+
+// +checklocksignore
+func (i *InodeNoStatFS) StateSave(stateSinkObject state.Sink) {
+ i.beforeSave()
+}
+
+func (i *InodeNoStatFS) afterLoad() {}
+
+// +checklocksignore
+func (i *InodeNoStatFS) StateLoad(stateSourceObject state.Source) {
+}
+
+func (fs *Filesystem) StateTypeName() string {
+ return "pkg/sentry/fsimpl/kernfs.Filesystem"
+}
+
+func (fs *Filesystem) StateFields() []string {
+ return []string{
+ "vfsfs",
+ "deferredDecRefs",
+ "nextInoMinusOne",
+ "cachedDentries",
+ "cachedDentriesLen",
+ "MaxCachedDentries",
+ "root",
+ }
+}
+
+func (fs *Filesystem) beforeSave() {}
+
+// +checklocksignore
+func (fs *Filesystem) StateSave(stateSinkObject state.Sink) {
+ fs.beforeSave()
+ stateSinkObject.Save(0, &fs.vfsfs)
+ stateSinkObject.Save(1, &fs.deferredDecRefs)
+ stateSinkObject.Save(2, &fs.nextInoMinusOne)
+ stateSinkObject.Save(3, &fs.cachedDentries)
+ stateSinkObject.Save(4, &fs.cachedDentriesLen)
+ stateSinkObject.Save(5, &fs.MaxCachedDentries)
+ stateSinkObject.Save(6, &fs.root)
+}
+
+func (fs *Filesystem) afterLoad() {}
+
+// +checklocksignore
+func (fs *Filesystem) StateLoad(stateSourceObject state.Source) {
+ stateSourceObject.Load(0, &fs.vfsfs)
+ stateSourceObject.Load(1, &fs.deferredDecRefs)
+ stateSourceObject.Load(2, &fs.nextInoMinusOne)
+ stateSourceObject.Load(3, &fs.cachedDentries)
+ stateSourceObject.Load(4, &fs.cachedDentriesLen)
+ stateSourceObject.Load(5, &fs.MaxCachedDentries)
+ stateSourceObject.Load(6, &fs.root)
+}
+
+func (d *Dentry) StateTypeName() string {
+ return "pkg/sentry/fsimpl/kernfs.Dentry"
+}
+
+func (d *Dentry) StateFields() []string {
+ return []string{
+ "vfsd",
+ "refs",
+ "fs",
+ "flags",
+ "parent",
+ "name",
+ "cached",
+ "dentryEntry",
+ "children",
+ "inode",
+ }
+}
+
+func (d *Dentry) beforeSave() {}
+
+// +checklocksignore
+func (d *Dentry) StateSave(stateSinkObject state.Sink) {
+ d.beforeSave()
+ stateSinkObject.Save(0, &d.vfsd)
+ stateSinkObject.Save(1, &d.refs)
+ stateSinkObject.Save(2, &d.fs)
+ stateSinkObject.Save(3, &d.flags)
+ stateSinkObject.Save(4, &d.parent)
+ stateSinkObject.Save(5, &d.name)
+ stateSinkObject.Save(6, &d.cached)
+ stateSinkObject.Save(7, &d.dentryEntry)
+ stateSinkObject.Save(8, &d.children)
+ stateSinkObject.Save(9, &d.inode)
+}
+
+// +checklocksignore
+func (d *Dentry) StateLoad(stateSourceObject state.Source) {
+ stateSourceObject.Load(0, &d.vfsd)
+ stateSourceObject.Load(1, &d.refs)
+ stateSourceObject.Load(2, &d.fs)
+ stateSourceObject.Load(3, &d.flags)
+ stateSourceObject.Load(4, &d.parent)
+ stateSourceObject.Load(5, &d.name)
+ stateSourceObject.Load(6, &d.cached)
+ stateSourceObject.Load(7, &d.dentryEntry)
+ stateSourceObject.Load(8, &d.children)
+ stateSourceObject.Load(9, &d.inode)
+ stateSourceObject.AfterLoad(d.afterLoad)
+}
+
+func (i *inodePlatformFile) StateTypeName() string {
+ return "pkg/sentry/fsimpl/kernfs.inodePlatformFile"
+}
+
+func (i *inodePlatformFile) StateFields() []string {
+ return []string{
+ "hostFD",
+ "fdRefs",
+ "fileMapper",
+ }
+}
+
+func (i *inodePlatformFile) beforeSave() {}
+
+// +checklocksignore
+func (i *inodePlatformFile) StateSave(stateSinkObject state.Sink) {
+ i.beforeSave()
+ stateSinkObject.Save(0, &i.hostFD)
+ stateSinkObject.Save(1, &i.fdRefs)
+ stateSinkObject.Save(2, &i.fileMapper)
+}
+
+// +checklocksignore
+func (i *inodePlatformFile) StateLoad(stateSourceObject state.Source) {
+ stateSourceObject.Load(0, &i.hostFD)
+ stateSourceObject.Load(1, &i.fdRefs)
+ stateSourceObject.Load(2, &i.fileMapper)
+ stateSourceObject.AfterLoad(i.afterLoad)
+}
+
+func (i *CachedMappable) StateTypeName() string {
+ return "pkg/sentry/fsimpl/kernfs.CachedMappable"
+}
+
+func (i *CachedMappable) StateFields() []string {
+ return []string{
+ "mappings",
+ "pf",
+ }
+}
+
+func (i *CachedMappable) beforeSave() {}
+
+// +checklocksignore
+func (i *CachedMappable) StateSave(stateSinkObject state.Sink) {
+ i.beforeSave()
+ stateSinkObject.Save(0, &i.mappings)
+ stateSinkObject.Save(1, &i.pf)
+}
+
+func (i *CachedMappable) afterLoad() {}
+
+// +checklocksignore
+func (i *CachedMappable) StateLoad(stateSourceObject state.Source) {
+ stateSourceObject.Load(0, &i.mappings)
+ stateSourceObject.Load(1, &i.pf)
+}
+
+func (l *slotList) StateTypeName() string {
+ return "pkg/sentry/fsimpl/kernfs.slotList"
+}
+
+func (l *slotList) StateFields() []string {
+ return []string{
+ "head",
+ "tail",
+ }
+}
+
+func (l *slotList) beforeSave() {}
+
+// +checklocksignore
+func (l *slotList) StateSave(stateSinkObject state.Sink) {
+ l.beforeSave()
+ stateSinkObject.Save(0, &l.head)
+ stateSinkObject.Save(1, &l.tail)
+}
+
+func (l *slotList) afterLoad() {}
+
+// +checklocksignore
+func (l *slotList) StateLoad(stateSourceObject state.Source) {
+ stateSourceObject.Load(0, &l.head)
+ stateSourceObject.Load(1, &l.tail)
+}
+
+func (e *slotEntry) StateTypeName() string {
+ return "pkg/sentry/fsimpl/kernfs.slotEntry"
+}
+
+func (e *slotEntry) StateFields() []string {
+ return []string{
+ "next",
+ "prev",
+ }
+}
+
+func (e *slotEntry) beforeSave() {}
+
+// +checklocksignore
+func (e *slotEntry) StateSave(stateSinkObject state.Sink) {
+ e.beforeSave()
+ stateSinkObject.Save(0, &e.next)
+ stateSinkObject.Save(1, &e.prev)
+}
+
+func (e *slotEntry) afterLoad() {}
+
+// +checklocksignore
+func (e *slotEntry) StateLoad(stateSourceObject state.Source) {
+ stateSourceObject.Load(0, &e.next)
+ stateSourceObject.Load(1, &e.prev)
+}
+
+func (r *StaticDirectoryRefs) StateTypeName() string {
+ return "pkg/sentry/fsimpl/kernfs.StaticDirectoryRefs"
+}
+
+func (r *StaticDirectoryRefs) StateFields() []string {
+ return []string{
+ "refCount",
+ }
+}
+
+func (r *StaticDirectoryRefs) beforeSave() {}
+
+// +checklocksignore
+func (r *StaticDirectoryRefs) StateSave(stateSinkObject state.Sink) {
+ r.beforeSave()
+ stateSinkObject.Save(0, &r.refCount)
+}
+
+// +checklocksignore
+func (r *StaticDirectoryRefs) StateLoad(stateSourceObject state.Source) {
+ stateSourceObject.Load(0, &r.refCount)
+ stateSourceObject.AfterLoad(r.afterLoad)
+}
+
+func (s *StaticSymlink) StateTypeName() string {
+ return "pkg/sentry/fsimpl/kernfs.StaticSymlink"
+}
+
+func (s *StaticSymlink) StateFields() []string {
+ return []string{
+ "InodeAttrs",
+ "InodeNoopRefCount",
+ "InodeSymlink",
+ "InodeNoStatFS",
+ "target",
+ }
+}
+
+func (s *StaticSymlink) beforeSave() {}
+
+// +checklocksignore
+func (s *StaticSymlink) StateSave(stateSinkObject state.Sink) {
+ s.beforeSave()
+ stateSinkObject.Save(0, &s.InodeAttrs)
+ stateSinkObject.Save(1, &s.InodeNoopRefCount)
+ stateSinkObject.Save(2, &s.InodeSymlink)
+ stateSinkObject.Save(3, &s.InodeNoStatFS)
+ stateSinkObject.Save(4, &s.target)
+}
+
+func (s *StaticSymlink) afterLoad() {}
+
+// +checklocksignore
+func (s *StaticSymlink) StateLoad(stateSourceObject state.Source) {
+ stateSourceObject.Load(0, &s.InodeAttrs)
+ stateSourceObject.Load(1, &s.InodeNoopRefCount)
+ stateSourceObject.Load(2, &s.InodeSymlink)
+ stateSourceObject.Load(3, &s.InodeNoStatFS)
+ stateSourceObject.Load(4, &s.target)
+}
+
+func (dir *syntheticDirectory) StateTypeName() string {
+ return "pkg/sentry/fsimpl/kernfs.syntheticDirectory"
+}
+
+func (dir *syntheticDirectory) StateFields() []string {
+ return []string{
+ "InodeAlwaysValid",
+ "InodeAttrs",
+ "InodeNoStatFS",
+ "InodeNotSymlink",
+ "OrderedChildren",
+ "syntheticDirectoryRefs",
+ "locks",
+ }
+}
+
+func (dir *syntheticDirectory) beforeSave() {}
+
+// +checklocksignore
+func (dir *syntheticDirectory) StateSave(stateSinkObject state.Sink) {
+ dir.beforeSave()
+ stateSinkObject.Save(0, &dir.InodeAlwaysValid)
+ stateSinkObject.Save(1, &dir.InodeAttrs)
+ stateSinkObject.Save(2, &dir.InodeNoStatFS)
+ stateSinkObject.Save(3, &dir.InodeNotSymlink)
+ stateSinkObject.Save(4, &dir.OrderedChildren)
+ stateSinkObject.Save(5, &dir.syntheticDirectoryRefs)
+ stateSinkObject.Save(6, &dir.locks)
+}
+
+func (dir *syntheticDirectory) afterLoad() {}
+
+// +checklocksignore
+func (dir *syntheticDirectory) StateLoad(stateSourceObject state.Source) {
+ stateSourceObject.Load(0, &dir.InodeAlwaysValid)
+ stateSourceObject.Load(1, &dir.InodeAttrs)
+ stateSourceObject.Load(2, &dir.InodeNoStatFS)
+ stateSourceObject.Load(3, &dir.InodeNotSymlink)
+ stateSourceObject.Load(4, &dir.OrderedChildren)
+ stateSourceObject.Load(5, &dir.syntheticDirectoryRefs)
+ stateSourceObject.Load(6, &dir.locks)
+}
+
+func (r *syntheticDirectoryRefs) StateTypeName() string {
+ return "pkg/sentry/fsimpl/kernfs.syntheticDirectoryRefs"
+}
+
+func (r *syntheticDirectoryRefs) StateFields() []string {
+ return []string{
+ "refCount",
+ }
+}
+
+func (r *syntheticDirectoryRefs) beforeSave() {}
+
+// +checklocksignore
+func (r *syntheticDirectoryRefs) StateSave(stateSinkObject state.Sink) {
+ r.beforeSave()
+ stateSinkObject.Save(0, &r.refCount)
+}
+
+// +checklocksignore
+func (r *syntheticDirectoryRefs) StateLoad(stateSourceObject state.Source) {
+ stateSourceObject.Load(0, &r.refCount)
+ stateSourceObject.AfterLoad(r.afterLoad)
+}
+
+func init() {
+ state.Register((*dentryList)(nil))
+ state.Register((*dentryEntry)(nil))
+ state.Register((*DynamicBytesFile)(nil))
+ state.Register((*DynamicBytesFD)(nil))
+ state.Register((*SeekEndConfig)(nil))
+ state.Register((*GenericDirectoryFDOptions)(nil))
+ state.Register((*GenericDirectoryFD)(nil))
+ state.Register((*InodeNoopRefCount)(nil))
+ state.Register((*InodeDirectoryNoNewChildren)(nil))
+ state.Register((*InodeNotDirectory)(nil))
+ state.Register((*InodeNotSymlink)(nil))
+ state.Register((*InodeAttrs)(nil))
+ state.Register((*slot)(nil))
+ state.Register((*OrderedChildrenOptions)(nil))
+ state.Register((*OrderedChildren)(nil))
+ state.Register((*InodeSymlink)(nil))
+ state.Register((*StaticDirectory)(nil))
+ state.Register((*InodeAlwaysValid)(nil))
+ state.Register((*InodeTemporary)(nil))
+ state.Register((*InodeNoStatFS)(nil))
+ state.Register((*Filesystem)(nil))
+ state.Register((*Dentry)(nil))
+ state.Register((*inodePlatformFile)(nil))
+ state.Register((*CachedMappable)(nil))
+ state.Register((*slotList)(nil))
+ state.Register((*slotEntry)(nil))
+ state.Register((*StaticDirectoryRefs)(nil))
+ state.Register((*StaticSymlink)(nil))
+ state.Register((*syntheticDirectory)(nil))
+ state.Register((*syntheticDirectoryRefs)(nil))
+}
diff --git a/pkg/sentry/fsimpl/kernfs/kernfs_test.go b/pkg/sentry/fsimpl/kernfs/kernfs_test.go
deleted file mode 100644
index a2aba9321..000000000
--- a/pkg/sentry/fsimpl/kernfs/kernfs_test.go
+++ /dev/null
@@ -1,409 +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 kernfs_test
-
-import (
- "bytes"
- "fmt"
- "testing"
-
- "github.com/google/go-cmp/cmp"
- "gvisor.dev/gvisor/pkg/abi/linux"
- "gvisor.dev/gvisor/pkg/context"
- "gvisor.dev/gvisor/pkg/errors/linuxerr"
- "gvisor.dev/gvisor/pkg/fspath"
- "gvisor.dev/gvisor/pkg/sentry/contexttest"
- "gvisor.dev/gvisor/pkg/sentry/fsimpl/kernfs"
- "gvisor.dev/gvisor/pkg/sentry/fsimpl/testutil"
- "gvisor.dev/gvisor/pkg/sentry/kernel/auth"
- "gvisor.dev/gvisor/pkg/sentry/vfs"
- "gvisor.dev/gvisor/pkg/usermem"
-)
-
-const defaultMode linux.FileMode = 01777
-const staticFileContent = "This is sample content for a static test file."
-
-// RootDentryFn is a generator function for creating the root dentry of a test
-// filesystem. See newTestSystem.
-type RootDentryFn func(context.Context, *auth.Credentials, *filesystem) kernfs.Inode
-
-// newTestSystem sets up a minimal environment for running a test, including an
-// instance of a test filesystem. Tests can control the contents of the
-// filesystem by providing an appropriate rootFn, which should return a
-// pre-populated root dentry.
-func newTestSystem(t *testing.T, rootFn RootDentryFn) *testutil.System {
- ctx := contexttest.Context(t)
- creds := auth.CredentialsFromContext(ctx)
- v := &vfs.VirtualFilesystem{}
- if err := v.Init(ctx); err != nil {
- t.Fatalf("VFS init: %v", err)
- }
- v.MustRegisterFilesystemType("testfs", &fsType{rootFn: rootFn}, &vfs.RegisterFilesystemTypeOptions{
- AllowUserMount: true,
- })
- mns, err := v.NewMountNamespace(ctx, creds, "", "testfs", &vfs.MountOptions{})
- if err != nil {
- t.Fatalf("Failed to create testfs root mount: %v", err)
- }
- return testutil.NewSystem(ctx, t, v, mns)
-}
-
-type fsType struct {
- rootFn RootDentryFn
-}
-
-type filesystem struct {
- kernfs.Filesystem
-}
-
-// MountOptions implements vfs.FilesystemImpl.MountOptions.
-func (fs *filesystem) MountOptions() string {
- return ""
-}
-
-type file struct {
- kernfs.DynamicBytesFile
- content string
-}
-
-func (fs *filesystem) newFile(ctx context.Context, creds *auth.Credentials, content string) kernfs.Inode {
- f := &file{}
- f.content = content
- f.DynamicBytesFile.Init(ctx, creds, 0 /* devMajor */, 0 /* devMinor */, fs.NextIno(), f, 0777)
- return f
-}
-
-func (f *file) Generate(ctx context.Context, buf *bytes.Buffer) error {
- fmt.Fprintf(buf, "%s", f.content)
- return nil
-}
-
-type attrs struct {
- kernfs.InodeAttrs
-}
-
-func (*attrs) SetStat(context.Context, *vfs.Filesystem, *auth.Credentials, vfs.SetStatOptions) error {
- return linuxerr.EPERM
-}
-
-type readonlyDir struct {
- readonlyDirRefs
- attrs
- kernfs.InodeAlwaysValid
- kernfs.InodeDirectoryNoNewChildren
- kernfs.InodeNoStatFS
- kernfs.InodeNotSymlink
- kernfs.InodeTemporary
- kernfs.OrderedChildren
-
- locks vfs.FileLocks
-}
-
-func (fs *filesystem) newReadonlyDir(ctx context.Context, creds *auth.Credentials, mode linux.FileMode, contents map[string]kernfs.Inode) kernfs.Inode {
- dir := &readonlyDir{}
- dir.attrs.Init(ctx, creds, 0 /* devMajor */, 0 /* devMinor */, fs.NextIno(), linux.ModeDirectory|mode)
- dir.OrderedChildren.Init(kernfs.OrderedChildrenOptions{})
- dir.InitRefs()
- dir.IncLinks(dir.OrderedChildren.Populate(contents))
- return dir
-}
-
-func (d *readonlyDir) Open(ctx context.Context, rp *vfs.ResolvingPath, kd *kernfs.Dentry, opts vfs.OpenOptions) (*vfs.FileDescription, error) {
- fd, err := kernfs.NewGenericDirectoryFD(rp.Mount(), kd, &d.OrderedChildren, &d.locks, &opts, kernfs.GenericDirectoryFDOptions{
- SeekEnd: kernfs.SeekEndStaticEntries,
- })
- if err != nil {
- return nil, err
- }
- return fd.VFSFileDescription(), nil
-}
-
-func (d *readonlyDir) DecRef(ctx context.Context) {
- d.readonlyDirRefs.DecRef(func() { d.Destroy(ctx) })
-}
-
-type dir struct {
- dirRefs
- attrs
- kernfs.InodeAlwaysValid
- kernfs.InodeNotSymlink
- kernfs.InodeNoStatFS
- kernfs.InodeTemporary
- kernfs.OrderedChildren
-
- locks vfs.FileLocks
-
- fs *filesystem
-}
-
-func (fs *filesystem) newDir(ctx context.Context, creds *auth.Credentials, mode linux.FileMode, contents map[string]kernfs.Inode) kernfs.Inode {
- dir := &dir{}
- dir.fs = fs
- dir.attrs.Init(ctx, creds, 0 /* devMajor */, 0 /* devMinor */, fs.NextIno(), linux.ModeDirectory|mode)
- dir.OrderedChildren.Init(kernfs.OrderedChildrenOptions{Writable: true})
- dir.InitRefs()
-
- dir.IncLinks(dir.OrderedChildren.Populate(contents))
- return dir
-}
-
-func (d *dir) Open(ctx context.Context, rp *vfs.ResolvingPath, kd *kernfs.Dentry, opts vfs.OpenOptions) (*vfs.FileDescription, error) {
- fd, err := kernfs.NewGenericDirectoryFD(rp.Mount(), kd, &d.OrderedChildren, &d.locks, &opts, kernfs.GenericDirectoryFDOptions{
- SeekEnd: kernfs.SeekEndStaticEntries,
- })
- if err != nil {
- return nil, err
- }
- return fd.VFSFileDescription(), nil
-}
-
-func (d *dir) DecRef(ctx context.Context) {
- d.dirRefs.DecRef(func() { d.Destroy(ctx) })
-}
-
-func (d *dir) NewDir(ctx context.Context, name string, opts vfs.MkdirOptions) (kernfs.Inode, error) {
- creds := auth.CredentialsFromContext(ctx)
- dir := d.fs.newDir(ctx, creds, opts.Mode, nil)
- if err := d.OrderedChildren.Insert(name, dir); err != nil {
- dir.DecRef(ctx)
- return nil, err
- }
- d.TouchCMtime(ctx)
- d.IncLinks(1)
- return dir, nil
-}
-
-func (d *dir) NewFile(ctx context.Context, name string, opts vfs.OpenOptions) (kernfs.Inode, error) {
- creds := auth.CredentialsFromContext(ctx)
- f := d.fs.newFile(ctx, creds, "")
- if err := d.OrderedChildren.Insert(name, f); err != nil {
- f.DecRef(ctx)
- return nil, err
- }
- d.TouchCMtime(ctx)
- return f, nil
-}
-
-func (*dir) NewLink(context.Context, string, kernfs.Inode) (kernfs.Inode, error) {
- return nil, linuxerr.EPERM
-}
-
-func (*dir) NewSymlink(context.Context, string, string) (kernfs.Inode, error) {
- return nil, linuxerr.EPERM
-}
-
-func (*dir) NewNode(context.Context, string, vfs.MknodOptions) (kernfs.Inode, error) {
- return nil, linuxerr.EPERM
-}
-
-func (fsType) Name() string {
- return "kernfs"
-}
-
-func (fsType) Release(ctx context.Context) {}
-
-func (fst fsType) GetFilesystem(ctx context.Context, vfsObj *vfs.VirtualFilesystem, creds *auth.Credentials, source string, opt vfs.GetFilesystemOptions) (*vfs.Filesystem, *vfs.Dentry, error) {
- fs := &filesystem{}
- fs.VFSFilesystem().Init(vfsObj, &fst, fs)
- root := fst.rootFn(ctx, creds, fs)
- var d kernfs.Dentry
- d.Init(&fs.Filesystem, root)
- return fs.VFSFilesystem(), d.VFSDentry(), nil
-}
-
-// -------------------- Remainder of the file are test cases --------------------
-
-func TestBasic(t *testing.T) {
- sys := newTestSystem(t, func(ctx context.Context, creds *auth.Credentials, fs *filesystem) kernfs.Inode {
- return fs.newReadonlyDir(ctx, creds, 0755, map[string]kernfs.Inode{
- "file1": fs.newFile(ctx, creds, staticFileContent),
- })
- })
- defer sys.Destroy()
- sys.GetDentryOrDie(sys.PathOpAtRoot("file1")).DecRef(sys.Ctx)
-}
-
-func TestMkdirGetDentry(t *testing.T) {
- sys := newTestSystem(t, func(ctx context.Context, creds *auth.Credentials, fs *filesystem) kernfs.Inode {
- return fs.newReadonlyDir(ctx, creds, 0755, map[string]kernfs.Inode{
- "dir1": fs.newDir(ctx, creds, 0755, nil),
- })
- })
- defer sys.Destroy()
-
- pop := sys.PathOpAtRoot("dir1/a new directory")
- if err := sys.VFS.MkdirAt(sys.Ctx, sys.Creds, pop, &vfs.MkdirOptions{Mode: 0755}); err != nil {
- t.Fatalf("MkdirAt for PathOperation %+v failed: %v", pop, err)
- }
- sys.GetDentryOrDie(pop).DecRef(sys.Ctx)
-}
-
-func TestReadStaticFile(t *testing.T) {
- sys := newTestSystem(t, func(ctx context.Context, creds *auth.Credentials, fs *filesystem) kernfs.Inode {
- return fs.newReadonlyDir(ctx, creds, 0755, map[string]kernfs.Inode{
- "file1": fs.newFile(ctx, creds, staticFileContent),
- })
- })
- defer sys.Destroy()
-
- pop := sys.PathOpAtRoot("file1")
- fd, err := sys.VFS.OpenAt(sys.Ctx, sys.Creds, pop, &vfs.OpenOptions{
- Flags: linux.O_RDONLY,
- })
- if err != nil {
- t.Fatalf("OpenAt for PathOperation %+v failed: %v", pop, err)
- }
- defer fd.DecRef(sys.Ctx)
-
- content, err := sys.ReadToEnd(fd)
- if err != nil {
- t.Fatalf("Read failed: %v", err)
- }
- if diff := cmp.Diff(staticFileContent, content); diff != "" {
- t.Fatalf("Read returned unexpected data:\n--- want\n+++ got\n%v", diff)
- }
-}
-
-func TestCreateNewFileInStaticDir(t *testing.T) {
- sys := newTestSystem(t, func(ctx context.Context, creds *auth.Credentials, fs *filesystem) kernfs.Inode {
- return fs.newReadonlyDir(ctx, creds, 0755, map[string]kernfs.Inode{
- "dir1": fs.newDir(ctx, creds, 0755, nil),
- })
- })
- defer sys.Destroy()
-
- pop := sys.PathOpAtRoot("dir1/newfile")
- opts := &vfs.OpenOptions{Flags: linux.O_CREAT | linux.O_EXCL, Mode: defaultMode}
- fd, err := sys.VFS.OpenAt(sys.Ctx, sys.Creds, pop, opts)
- if err != nil {
- t.Fatalf("OpenAt(pop:%+v, opts:%+v) failed: %v", pop, opts, err)
- }
-
- // Close the file. The file should persist.
- fd.DecRef(sys.Ctx)
-
- fd, err = sys.VFS.OpenAt(sys.Ctx, sys.Creds, pop, &vfs.OpenOptions{
- Flags: linux.O_RDONLY,
- })
- if err != nil {
- t.Fatalf("OpenAt(pop:%+v) = %+v failed: %v", pop, fd, err)
- }
- fd.DecRef(sys.Ctx)
-}
-
-func TestDirFDReadWrite(t *testing.T) {
- sys := newTestSystem(t, func(ctx context.Context, creds *auth.Credentials, fs *filesystem) kernfs.Inode {
- return fs.newReadonlyDir(ctx, creds, 0755, nil)
- })
- defer sys.Destroy()
-
- pop := sys.PathOpAtRoot("/")
- fd, err := sys.VFS.OpenAt(sys.Ctx, sys.Creds, pop, &vfs.OpenOptions{
- Flags: linux.O_RDONLY,
- })
- if err != nil {
- t.Fatalf("OpenAt for PathOperation %+v failed: %v", pop, err)
- }
- defer fd.DecRef(sys.Ctx)
-
- // Read/Write should fail for directory FDs.
- if _, err := fd.Read(sys.Ctx, usermem.BytesIOSequence([]byte{}), vfs.ReadOptions{}); !linuxerr.Equals(linuxerr.EISDIR, err) {
- t.Fatalf("Read for directory FD failed with unexpected error: %v", err)
- }
- if _, err := fd.Write(sys.Ctx, usermem.BytesIOSequence([]byte{}), vfs.WriteOptions{}); !linuxerr.Equals(linuxerr.EBADF, err) {
- t.Fatalf("Write for directory FD failed with unexpected error: %v", err)
- }
-}
-
-func TestDirFDIterDirents(t *testing.T) {
- sys := newTestSystem(t, func(ctx context.Context, creds *auth.Credentials, fs *filesystem) kernfs.Inode {
- return fs.newReadonlyDir(ctx, creds, 0755, map[string]kernfs.Inode{
- // Fill root with nodes backed by various inode implementations.
- "dir1": fs.newReadonlyDir(ctx, creds, 0755, nil),
- "dir2": fs.newDir(ctx, creds, 0755, map[string]kernfs.Inode{
- "dir3": fs.newDir(ctx, creds, 0755, nil),
- }),
- "file1": fs.newFile(ctx, creds, staticFileContent),
- })
- })
- defer sys.Destroy()
-
- pop := sys.PathOpAtRoot("/")
- sys.AssertAllDirentTypes(sys.ListDirents(pop), map[string]testutil.DirentType{
- "dir1": linux.DT_DIR,
- "dir2": linux.DT_DIR,
- "file1": linux.DT_REG,
- })
-}
-
-func TestDirWalkDentryTree(t *testing.T) {
- sys := newTestSystem(t, func(ctx context.Context, creds *auth.Credentials, fs *filesystem) kernfs.Inode {
- return fs.newDir(ctx, creds, 0755, map[string]kernfs.Inode{
- "dir1": fs.newDir(ctx, creds, 0755, nil),
- "dir2": fs.newDir(ctx, creds, 0755, map[string]kernfs.Inode{
- "file1": fs.newFile(ctx, creds, staticFileContent),
- "dir3": fs.newDir(ctx, creds, 0755, nil),
- }),
- })
- })
- defer sys.Destroy()
-
- testWalk := func(from *kernfs.Dentry, getDentryPath, walkPath string, expectedErr error) {
- var d *kernfs.Dentry
- if getDentryPath != "" {
- pop := sys.PathOpAtRoot(getDentryPath)
- vd := sys.GetDentryOrDie(pop)
- defer vd.DecRef(sys.Ctx)
- d = vd.Dentry().Impl().(*kernfs.Dentry)
- }
-
- match, err := from.WalkDentryTree(sys.Ctx, sys.VFS, fspath.Parse(walkPath))
- if err == nil {
- defer match.DecRef(sys.Ctx)
- }
-
- if err != expectedErr {
- t.Fatalf("WalkDentryTree from %q to %q (with expected error: %v) unexpected error, want: %v, got: %v", from.FSLocalPath(), walkPath, expectedErr, expectedErr, err)
- }
- if expectedErr != nil {
- return
- }
-
- if d != match {
- t.Fatalf("WalkDentryTree from %q to %q (with expected error: %v) found unexpected dentry; want: %v, got: %v", from.FSLocalPath(), walkPath, expectedErr, d, match)
- }
- }
-
- rootD := sys.Root.Dentry().Impl().(*kernfs.Dentry)
-
- testWalk(rootD, "dir1", "/dir1", nil)
- testWalk(rootD, "", "/dir-non-existent", linuxerr.ENOENT)
- testWalk(rootD, "", "/dir1/child-non-existent", linuxerr.ENOENT)
- testWalk(rootD, "", "/dir2/inner-non-existent/dir3", linuxerr.ENOENT)
-
- testWalk(rootD, "dir2/dir3", "/dir2/../dir2/dir3", nil)
- testWalk(rootD, "dir2/dir3", "/dir2/././dir3", nil)
- testWalk(rootD, "dir2/dir3", "/dir2/././dir3/.././dir3", nil)
-
- pop := sys.PathOpAtRoot("dir2")
- dir2VD := sys.GetDentryOrDie(pop)
- defer dir2VD.DecRef(sys.Ctx)
- dir2D := dir2VD.Dentry().Impl().(*kernfs.Dentry)
-
- testWalk(dir2D, "dir2/dir3", "/dir3", nil)
- testWalk(dir2D, "dir2/dir3", "/../../../dir3", nil)
- testWalk(dir2D, "dir2/file1", "/file1", nil)
- testWalk(dir2D, "dir2/file1", "file1", nil)
-}
diff --git a/pkg/sentry/fsimpl/kernfs/slot_list.go b/pkg/sentry/fsimpl/kernfs/slot_list.go
new file mode 100644
index 000000000..181fe7c8f
--- /dev/null
+++ b/pkg/sentry/fsimpl/kernfs/slot_list.go
@@ -0,0 +1,221 @@
+package kernfs
+
+// 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 slotElementMapper struct{}
+
+// linkerFor maps an Element to a Linker.
+//
+// This default implementation should be inlined.
+//
+//go:nosplit
+func (slotElementMapper) linkerFor(elem *slot) *slot { 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 slotList struct {
+ head *slot
+ tail *slot
+}
+
+// Reset resets list l to the empty state.
+func (l *slotList) Reset() {
+ l.head = nil
+ l.tail = nil
+}
+
+// Empty returns true iff the list is empty.
+//
+//go:nosplit
+func (l *slotList) Empty() bool {
+ return l.head == nil
+}
+
+// Front returns the first element of list l or nil.
+//
+//go:nosplit
+func (l *slotList) Front() *slot {
+ return l.head
+}
+
+// Back returns the last element of list l or nil.
+//
+//go:nosplit
+func (l *slotList) Back() *slot {
+ return l.tail
+}
+
+// Len returns the number of elements in the list.
+//
+// NOTE: This is an O(n) operation.
+//
+//go:nosplit
+func (l *slotList) Len() (count int) {
+ for e := l.Front(); e != nil; e = (slotElementMapper{}.linkerFor(e)).Next() {
+ count++
+ }
+ return count
+}
+
+// PushFront inserts the element e at the front of list l.
+//
+//go:nosplit
+func (l *slotList) PushFront(e *slot) {
+ linker := slotElementMapper{}.linkerFor(e)
+ linker.SetNext(l.head)
+ linker.SetPrev(nil)
+ if l.head != nil {
+ slotElementMapper{}.linkerFor(l.head).SetPrev(e)
+ } else {
+ l.tail = e
+ }
+
+ l.head = e
+}
+
+// PushBack inserts the element e at the back of list l.
+//
+//go:nosplit
+func (l *slotList) PushBack(e *slot) {
+ linker := slotElementMapper{}.linkerFor(e)
+ linker.SetNext(nil)
+ linker.SetPrev(l.tail)
+ if l.tail != nil {
+ slotElementMapper{}.linkerFor(l.tail).SetNext(e)
+ } else {
+ l.head = e
+ }
+
+ l.tail = e
+}
+
+// PushBackList inserts list m at the end of list l, emptying m.
+//
+//go:nosplit
+func (l *slotList) PushBackList(m *slotList) {
+ if l.head == nil {
+ l.head = m.head
+ l.tail = m.tail
+ } else if m.head != nil {
+ slotElementMapper{}.linkerFor(l.tail).SetNext(m.head)
+ slotElementMapper{}.linkerFor(m.head).SetPrev(l.tail)
+
+ l.tail = m.tail
+ }
+ m.head = nil
+ m.tail = nil
+}
+
+// InsertAfter inserts e after b.
+//
+//go:nosplit
+func (l *slotList) InsertAfter(b, e *slot) {
+ bLinker := slotElementMapper{}.linkerFor(b)
+ eLinker := slotElementMapper{}.linkerFor(e)
+
+ a := bLinker.Next()
+
+ eLinker.SetNext(a)
+ eLinker.SetPrev(b)
+ bLinker.SetNext(e)
+
+ if a != nil {
+ slotElementMapper{}.linkerFor(a).SetPrev(e)
+ } else {
+ l.tail = e
+ }
+}
+
+// InsertBefore inserts e before a.
+//
+//go:nosplit
+func (l *slotList) InsertBefore(a, e *slot) {
+ aLinker := slotElementMapper{}.linkerFor(a)
+ eLinker := slotElementMapper{}.linkerFor(e)
+
+ b := aLinker.Prev()
+ eLinker.SetNext(a)
+ eLinker.SetPrev(b)
+ aLinker.SetPrev(e)
+
+ if b != nil {
+ slotElementMapper{}.linkerFor(b).SetNext(e)
+ } else {
+ l.head = e
+ }
+}
+
+// Remove removes e from l.
+//
+//go:nosplit
+func (l *slotList) Remove(e *slot) {
+ linker := slotElementMapper{}.linkerFor(e)
+ prev := linker.Prev()
+ next := linker.Next()
+
+ if prev != nil {
+ slotElementMapper{}.linkerFor(prev).SetNext(next)
+ } else if l.head == e {
+ l.head = next
+ }
+
+ if next != nil {
+ slotElementMapper{}.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 slotEntry struct {
+ next *slot
+ prev *slot
+}
+
+// Next returns the entry that follows e in the list.
+//
+//go:nosplit
+func (e *slotEntry) Next() *slot {
+ return e.next
+}
+
+// Prev returns the entry that precedes e in the list.
+//
+//go:nosplit
+func (e *slotEntry) Prev() *slot {
+ return e.prev
+}
+
+// SetNext assigns 'entry' as the entry that follows e in the list.
+//
+//go:nosplit
+func (e *slotEntry) SetNext(elem *slot) {
+ e.next = elem
+}
+
+// SetPrev assigns 'entry' as the entry that precedes e in the list.
+//
+//go:nosplit
+func (e *slotEntry) SetPrev(elem *slot) {
+ e.prev = elem
+}
diff --git a/pkg/sentry/fsimpl/kernfs/static_directory_refs.go b/pkg/sentry/fsimpl/kernfs/static_directory_refs.go
new file mode 100644
index 000000000..69534a2d2
--- /dev/null
+++ b/pkg/sentry/fsimpl/kernfs/static_directory_refs.go
@@ -0,0 +1,140 @@
+package kernfs
+
+import (
+ "fmt"
+ "sync/atomic"
+
+ "gvisor.dev/gvisor/pkg/refsvfs2"
+)
+
+// enableLogging indicates whether reference-related events should be logged (with
+// stack traces). This is false by default and should only be set to true for
+// debugging purposes, as it can generate an extremely large amount of output
+// and drastically degrade performance.
+const StaticDirectoryenableLogging = false
+
+// obj 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 StaticDirectoryobj *StaticDirectory
+
+// Refs implements refs.RefCounter. It keeps a reference count using atomic
+// operations and calls the destructor when the count reaches zero.
+//
+// NOTE: Do not introduce additional fields to the Refs struct. It is used by
+// many filesystem objects, and we want to keep it as small as possible (i.e.,
+// the same size as using an int64 directly) to avoid taking up extra cache
+// space. In general, this template should not be extended at the cost of
+// performance. If it does not offer enough flexibility for a particular object
+// (example: b/187877947), we should implement the RefCounter/CheckedObject
+// interfaces manually.
+//
+// +stateify savable
+type StaticDirectoryRefs 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
+}
+
+// InitRefs initializes r with one reference and, if enabled, activates leak
+// checking.
+func (r *StaticDirectoryRefs) InitRefs() {
+ atomic.StoreInt64(&r.refCount, 1)
+ refsvfs2.Register(r)
+}
+
+// RefType implements refsvfs2.CheckedObject.RefType.
+func (r *StaticDirectoryRefs) RefType() string {
+ return fmt.Sprintf("%T", StaticDirectoryobj)[1:]
+}
+
+// LeakMessage implements refsvfs2.CheckedObject.LeakMessage.
+func (r *StaticDirectoryRefs) LeakMessage() string {
+ return fmt.Sprintf("[%s %p] reference count of %d instead of 0", r.RefType(), r, r.ReadRefs())
+}
+
+// LogRefs implements refsvfs2.CheckedObject.LogRefs.
+func (r *StaticDirectoryRefs) LogRefs() bool {
+ return StaticDirectoryenableLogging
+}
+
+// ReadRefs returns the current number of references. The returned count is
+// inherently racy and is unsafe to use without external synchronization.
+func (r *StaticDirectoryRefs) ReadRefs() int64 {
+ return atomic.LoadInt64(&r.refCount)
+}
+
+// IncRef implements refs.RefCounter.IncRef.
+//
+//go:nosplit
+func (r *StaticDirectoryRefs) IncRef() {
+ v := atomic.AddInt64(&r.refCount, 1)
+ if StaticDirectoryenableLogging {
+ refsvfs2.LogIncRef(r, v)
+ }
+ if v <= 1 {
+ panic(fmt.Sprintf("Incrementing non-positive count %p on %s", r, r.RefType()))
+ }
+}
+
+// TryIncRef implements refs.TryRefCounter.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 *StaticDirectoryRefs) TryIncRef() bool {
+ const speculativeRef = 1 << 32
+ if v := atomic.AddInt64(&r.refCount, speculativeRef); int32(v) == 0 {
+
+ atomic.AddInt64(&r.refCount, -speculativeRef)
+ return false
+ }
+
+ v := atomic.AddInt64(&r.refCount, -speculativeRef+1)
+ if StaticDirectoryenableLogging {
+ refsvfs2.LogTryIncRef(r, v)
+ }
+ 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 *StaticDirectoryRefs) DecRef(destroy func()) {
+ v := atomic.AddInt64(&r.refCount, -1)
+ if StaticDirectoryenableLogging {
+ refsvfs2.LogDecRef(r, v)
+ }
+ switch {
+ case v < 0:
+ panic(fmt.Sprintf("Decrementing non-positive ref count %p, owned by %s", r, r.RefType()))
+
+ case v == 0:
+ refsvfs2.Unregister(r)
+
+ if destroy != nil {
+ destroy()
+ }
+ }
+}
+
+func (r *StaticDirectoryRefs) afterLoad() {
+ if r.ReadRefs() > 0 {
+ refsvfs2.Register(r)
+ }
+}
diff --git a/pkg/sentry/fsimpl/kernfs/synthetic_directory_refs.go b/pkg/sentry/fsimpl/kernfs/synthetic_directory_refs.go
new file mode 100644
index 000000000..3c5fdf15e
--- /dev/null
+++ b/pkg/sentry/fsimpl/kernfs/synthetic_directory_refs.go
@@ -0,0 +1,140 @@
+package kernfs
+
+import (
+ "fmt"
+ "sync/atomic"
+
+ "gvisor.dev/gvisor/pkg/refsvfs2"
+)
+
+// enableLogging indicates whether reference-related events should be logged (with
+// stack traces). This is false by default and should only be set to true for
+// debugging purposes, as it can generate an extremely large amount of output
+// and drastically degrade performance.
+const syntheticDirectoryenableLogging = false
+
+// obj 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 syntheticDirectoryobj *syntheticDirectory
+
+// Refs implements refs.RefCounter. It keeps a reference count using atomic
+// operations and calls the destructor when the count reaches zero.
+//
+// NOTE: Do not introduce additional fields to the Refs struct. It is used by
+// many filesystem objects, and we want to keep it as small as possible (i.e.,
+// the same size as using an int64 directly) to avoid taking up extra cache
+// space. In general, this template should not be extended at the cost of
+// performance. If it does not offer enough flexibility for a particular object
+// (example: b/187877947), we should implement the RefCounter/CheckedObject
+// interfaces manually.
+//
+// +stateify savable
+type syntheticDirectoryRefs 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
+}
+
+// InitRefs initializes r with one reference and, if enabled, activates leak
+// checking.
+func (r *syntheticDirectoryRefs) InitRefs() {
+ atomic.StoreInt64(&r.refCount, 1)
+ refsvfs2.Register(r)
+}
+
+// RefType implements refsvfs2.CheckedObject.RefType.
+func (r *syntheticDirectoryRefs) RefType() string {
+ return fmt.Sprintf("%T", syntheticDirectoryobj)[1:]
+}
+
+// LeakMessage implements refsvfs2.CheckedObject.LeakMessage.
+func (r *syntheticDirectoryRefs) LeakMessage() string {
+ return fmt.Sprintf("[%s %p] reference count of %d instead of 0", r.RefType(), r, r.ReadRefs())
+}
+
+// LogRefs implements refsvfs2.CheckedObject.LogRefs.
+func (r *syntheticDirectoryRefs) LogRefs() bool {
+ return syntheticDirectoryenableLogging
+}
+
+// ReadRefs returns the current number of references. The returned count is
+// inherently racy and is unsafe to use without external synchronization.
+func (r *syntheticDirectoryRefs) ReadRefs() int64 {
+ return atomic.LoadInt64(&r.refCount)
+}
+
+// IncRef implements refs.RefCounter.IncRef.
+//
+//go:nosplit
+func (r *syntheticDirectoryRefs) IncRef() {
+ v := atomic.AddInt64(&r.refCount, 1)
+ if syntheticDirectoryenableLogging {
+ refsvfs2.LogIncRef(r, v)
+ }
+ if v <= 1 {
+ panic(fmt.Sprintf("Incrementing non-positive count %p on %s", r, r.RefType()))
+ }
+}
+
+// TryIncRef implements refs.TryRefCounter.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 *syntheticDirectoryRefs) TryIncRef() bool {
+ const speculativeRef = 1 << 32
+ if v := atomic.AddInt64(&r.refCount, speculativeRef); int32(v) == 0 {
+
+ atomic.AddInt64(&r.refCount, -speculativeRef)
+ return false
+ }
+
+ v := atomic.AddInt64(&r.refCount, -speculativeRef+1)
+ if syntheticDirectoryenableLogging {
+ refsvfs2.LogTryIncRef(r, v)
+ }
+ 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 *syntheticDirectoryRefs) DecRef(destroy func()) {
+ v := atomic.AddInt64(&r.refCount, -1)
+ if syntheticDirectoryenableLogging {
+ refsvfs2.LogDecRef(r, v)
+ }
+ switch {
+ case v < 0:
+ panic(fmt.Sprintf("Decrementing non-positive ref count %p, owned by %s", r, r.RefType()))
+
+ case v == 0:
+ refsvfs2.Unregister(r)
+
+ if destroy != nil {
+ destroy()
+ }
+ }
+}
+
+func (r *syntheticDirectoryRefs) afterLoad() {
+ if r.ReadRefs() > 0 {
+ refsvfs2.Register(r)
+ }
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-21 09:02:13 +0000