diff options
Diffstat (limited to 'pkg/sentry/kernel/epoll')
| -rw-r--r-- | pkg/sentry/kernel/epoll/BUILD | 14 | ||||
| -rw-r--r-- | pkg/sentry/kernel/epoll/epoll.go | 74 | ||||
| -rw-r--r-- | pkg/sentry/kernel/epoll/epoll_state.go | 16 | ||||
| -rw-r--r-- | pkg/sentry/kernel/epoll/epoll_test.go | 7 |
4 files changed, 51 insertions, 60 deletions
diff --git a/pkg/sentry/kernel/epoll/BUILD b/pkg/sentry/kernel/epoll/BUILD index 3361e8b7d..75eedd5a2 100644 --- a/pkg/sentry/kernel/epoll/BUILD +++ b/pkg/sentry/kernel/epoll/BUILD @@ -1,6 +1,5 @@ -load("@io_bazel_rules_go//go:def.bzl", "go_test") +load("//tools:defs.bzl", "go_library", "go_test") load("//tools/go_generics:defs.bzl", "go_template_instance") -load("//tools/go_stateify:defs.bzl", "go_library") package(licenses = ["notice"]) @@ -23,15 +22,16 @@ go_library( "epoll_list.go", "epoll_state.go", ], - importpath = "gvisor.dev/gvisor/pkg/sentry/kernel/epoll", visibility = ["//pkg/sentry:internal"], deps = [ + "//pkg/abi/linux", + "//pkg/context", "//pkg/refs", - "//pkg/sentry/context", "//pkg/sentry/fs", "//pkg/sentry/fs/anon", "//pkg/sentry/fs/fsutil", - "//pkg/sentry/usermem", + "//pkg/sync", + "//pkg/usermem", "//pkg/waiter", ], ) @@ -42,9 +42,9 @@ go_test( srcs = [ "epoll_test.go", ], - embed = [":epoll"], + library = ":epoll", deps = [ - "//pkg/sentry/context/contexttest", + "//pkg/sentry/contexttest", "//pkg/sentry/fs/filetest", "//pkg/waiter", ], diff --git a/pkg/sentry/kernel/epoll/epoll.go b/pkg/sentry/kernel/epoll/epoll.go index 9c0a4e1b4..15519f0df 100644 --- a/pkg/sentry/kernel/epoll/epoll.go +++ b/pkg/sentry/kernel/epoll/epoll.go @@ -18,31 +18,19 @@ package epoll import ( "fmt" - "sync" "syscall" + "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/refs" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/anon" "gvisor.dev/gvisor/pkg/sentry/fs/fsutil" - "gvisor.dev/gvisor/pkg/sentry/usermem" + "gvisor.dev/gvisor/pkg/sync" + "gvisor.dev/gvisor/pkg/usermem" "gvisor.dev/gvisor/pkg/waiter" ) -// Event describes the event mask that was observed and the user data to be -// returned when one of the events occurs. It has this format to match the linux -// format to avoid extra copying/allocation when writing events to userspace. -type Event struct { - // Events is the event mask containing the set of events that have been - // observed on an entry. - Events uint32 - - // Data is an opaque 64-bit value provided by the caller when adding the - // entry, and returned to the caller when the entry reports an event. - Data [2]int32 -} - // EntryFlags is a bitmask that holds an entry's flags. type EntryFlags int @@ -88,8 +76,8 @@ type pollEntry struct { // WeakRefGone implements refs.WeakRefUser.WeakRefGone. // weakReferenceGone is called when the file in the weak reference is destroyed. // The poll entry is removed in response to this. -func (p *pollEntry) WeakRefGone() { - p.epoll.RemoveEntry(p.id) +func (p *pollEntry) WeakRefGone(ctx context.Context) { + p.epoll.RemoveEntry(ctx, p.id) } // EventPoll holds all the state associated with an event poll object, that is, @@ -119,7 +107,7 @@ type EventPoll struct { // different lock to avoid circular lock acquisition order involving // the wait queue mutexes and mu. The full order is mu, observed file // wait queue mutex, then listsMu; this allows listsMu to be acquired - // when readyCallback is called. + // when (*pollEntry).Callback is called. // // An entry is always in one of the following lists: // readyList -- when there's a chance that it's ready to have @@ -128,7 +116,7 @@ type EventPoll struct { // readEvents() functions always call the entry's file // Readiness() function to confirm it's ready. // waitingList -- when there's no chance that the entry is ready, - // so it's waiting for the readyCallback to be called + // so it's waiting for the (*pollEntry).Callback to be called // on it before it gets moved to the readyList. // disabledList -- when the entry is disabled. This happens when // a one-shot entry gets delivered via readEvents(). @@ -156,14 +144,14 @@ func NewEventPoll(ctx context.Context) *fs.File { // name matches fs/eventpoll.c:epoll_create1. dirent := fs.NewDirent(ctx, anon.NewInode(ctx), fmt.Sprintf("anon_inode:[eventpoll]")) // Release the initial dirent reference after NewFile takes a reference. - defer dirent.DecRef() + defer dirent.DecRef(ctx) return fs.NewFile(ctx, dirent, fs.FileFlags{}, &EventPoll{ files: make(map[FileIdentifier]*pollEntry), }) } // Release implements fs.FileOperations.Release. -func (e *EventPoll) Release() { +func (e *EventPoll) Release(ctx context.Context) { // We need to take the lock now because files may be attempting to // remove entries in parallel if they get destroyed. e.mu.Lock() @@ -172,8 +160,9 @@ func (e *EventPoll) Release() { // Go through all entries and clean up. for _, entry := range e.files { entry.id.File.EventUnregister(&entry.waiter) - entry.file.Drop() + entry.file.Drop(ctx) } + e.files = nil } // Read implements fs.FileOperations.Read. @@ -226,9 +215,9 @@ func (e *EventPoll) Readiness(mask waiter.EventMask) waiter.EventMask { } // ReadEvents returns up to max available events. -func (e *EventPoll) ReadEvents(max int) []Event { +func (e *EventPoll) ReadEvents(max int) []linux.EpollEvent { var local pollEntryList - var ret []Event + var ret []linux.EpollEvent e.listsMu.Lock() @@ -250,7 +239,7 @@ func (e *EventPoll) ReadEvents(max int) []Event { } // Add event to the array that will be returned to caller. - ret = append(ret, Event{ + ret = append(ret, linux.EpollEvent{ Events: uint32(ready), Data: entry.userData, }) @@ -280,23 +269,23 @@ func (e *EventPoll) ReadEvents(max int) []Event { return ret } -// readyCallback is called when one of the files we're polling becomes ready. It -// moves said file to the readyList if it's currently in the waiting list. -type readyCallback struct{} - // Callback implements waiter.EntryCallback.Callback. -func (*readyCallback) Callback(w *waiter.Entry) { - entry := w.Context.(*pollEntry) - e := entry.epoll +// +// Callback is called when one of the files we're polling becomes ready. It +// moves said file to the readyList if it's currently in the waiting list. +func (p *pollEntry) Callback(*waiter.Entry) { + e := p.epoll e.listsMu.Lock() - if entry.curList == &e.waitingList { - e.waitingList.Remove(entry) - e.readyList.PushBack(entry) - entry.curList = &e.readyList + if p.curList == &e.waitingList { + e.waitingList.Remove(p) + e.readyList.PushBack(p) + p.curList = &e.readyList + e.listsMu.Unlock() e.Notify(waiter.EventIn) + return } e.listsMu.Unlock() @@ -319,7 +308,7 @@ func (e *EventPoll) initEntryReadiness(entry *pollEntry) { // Check if the file happens to already be in a ready state. ready := f.Readiness(entry.mask) & entry.mask if ready != 0 { - (*readyCallback).Callback(nil, &entry.waiter) + entry.Callback(&entry.waiter) } } @@ -389,10 +378,9 @@ func (e *EventPoll) AddEntry(id FileIdentifier, flags EntryFlags, mask waiter.Ev userData: data, epoll: e, flags: flags, - waiter: waiter.Entry{Callback: &readyCallback{}}, mask: mask, } - entry.waiter.Context = entry + entry.waiter.Callback = entry e.files[id] = entry entry.file = refs.NewWeakRef(id.File, entry) @@ -415,7 +403,7 @@ func (e *EventPoll) UpdateEntry(id FileIdentifier, flags EntryFlags, mask waiter } // Unregister the old mask and remove entry from the list it's in, so - // readyCallback is guaranteed to not be called on this entry anymore. + // (*pollEntry).Callback is guaranteed to not be called on this entry anymore. entry.id.File.EventUnregister(&entry.waiter) // Remove entry from whatever list it's in. This ensure that no other @@ -435,7 +423,7 @@ func (e *EventPoll) UpdateEntry(id FileIdentifier, flags EntryFlags, mask waiter } // RemoveEntry a files from the collection of observed files. -func (e *EventPoll) RemoveEntry(id FileIdentifier) error { +func (e *EventPoll) RemoveEntry(ctx context.Context, id FileIdentifier) error { e.mu.Lock() defer e.mu.Unlock() @@ -457,7 +445,7 @@ func (e *EventPoll) RemoveEntry(id FileIdentifier) error { // Remove file from map, and drop weak reference. delete(e.files, id) - entry.file.Drop() + entry.file.Drop(ctx) return nil } diff --git a/pkg/sentry/kernel/epoll/epoll_state.go b/pkg/sentry/kernel/epoll/epoll_state.go index a0d35d350..7c61e0258 100644 --- a/pkg/sentry/kernel/epoll/epoll_state.go +++ b/pkg/sentry/kernel/epoll/epoll_state.go @@ -21,8 +21,7 @@ import ( // afterLoad is invoked by stateify. func (p *pollEntry) afterLoad() { - p.waiter = waiter.Entry{Callback: &readyCallback{}} - p.waiter.Context = p + p.waiter.Callback = p p.file = refs.NewWeakRef(p.id.File, p) p.id.File.EventRegister(&p.waiter, p.mask) } @@ -38,11 +37,14 @@ func (e *EventPoll) afterLoad() { } } - for it := e.waitingList.Front(); it != nil; it = it.Next() { - if it.id.File.Readiness(it.mask) != 0 { - e.waitingList.Remove(it) - e.readyList.PushBack(it) - it.curList = &e.readyList + for it := e.waitingList.Front(); it != nil; { + entry := it + it = it.Next() + + if entry.id.File.Readiness(entry.mask) != 0 { + e.waitingList.Remove(entry) + e.readyList.PushBack(entry) + entry.curList = &e.readyList e.Notify(waiter.EventIn) } } diff --git a/pkg/sentry/kernel/epoll/epoll_test.go b/pkg/sentry/kernel/epoll/epoll_test.go index 4a20d4c82..55b505593 100644 --- a/pkg/sentry/kernel/epoll/epoll_test.go +++ b/pkg/sentry/kernel/epoll/epoll_test.go @@ -17,7 +17,7 @@ package epoll import ( "testing" - "gvisor.dev/gvisor/pkg/sentry/context/contexttest" + "gvisor.dev/gvisor/pkg/sentry/contexttest" "gvisor.dev/gvisor/pkg/sentry/fs/filetest" "gvisor.dev/gvisor/pkg/waiter" ) @@ -26,7 +26,8 @@ func TestFileDestroyed(t *testing.T) { f := filetest.NewTestFile(t) id := FileIdentifier{f, 12} - efile := NewEventPoll(contexttest.Context(t)) + ctx := contexttest.Context(t) + efile := NewEventPoll(ctx) e := efile.FileOperations.(*EventPoll) if err := e.AddEntry(id, 0, waiter.EventIn, [2]int32{}); err != nil { t.Fatalf("addEntry failed: %v", err) @@ -44,7 +45,7 @@ func TestFileDestroyed(t *testing.T) { } // Destroy the file. Check that we get no more events. - f.DecRef() + f.DecRef(ctx) evt = e.ReadEvents(1) if len(evt) != 0 { |