The waits-for relationship between an epoll instance and an inotify fd should
be restored.
This fixes flaky inotify vfs2 tests.
PiperOrigin-RevId: 340531367
Also, while we're here, make sure that gofer inotify events are generated when
files are created in remote revalidating mode.
Updates #1479.
PiperOrigin-RevId: 318536354
Events were only skipped on parent directories after their children were
unlinked; events on the unlinked file itself need to be skipped as well.
As a result, all Watches.Notify() calls need to know whether the dentry where
the call came from was unlinked.
Updates #1479.
PiperOrigin-RevId: 317979476
Because there is no inode structure stored in the sandbox, inotify watches
must be held on the dentry. This would be an issue in the presence of hard
links, where multiple dentries would need to share the same set of watches,
but in VFS2, we do not support the internal creation of hard links on gofer
fs. As a result, we make the assumption that every dentry corresponds to a
unique inode.
Furthermore, dentries can be cached and then evicted, even if the underlying
file has not be deleted. We must prevent this from occurring if there are any
watches that would be lost. Note that if the dentry was deleted or invalidated
(d.vfsd.IsDead()), we should still destroy it along with its watches.
Additionally, when a dentry’s last watch is removed, we cache it if it also
has zero references. This way, the dentry can eventually be evicted from
memory if it is no longer needed. This is accomplished with a new dentry
method, OnZeroWatches(), which is called by Inotify.RmWatch and
Inotify.Release. Note that it must be called after all inotify locks are
released to avoid violating lock order. Stress tests are added to make sure
that inotify operations don't deadlock with gofer.OnZeroWatches.
Updates #1479.
PiperOrigin-RevId: 317958034
LockFD is the generic implementation that can be embedded in
FileDescriptionImpl implementations. Unique lock ID is
maintained in vfs.FileDescription and is created on demand.
Updates #1480
PiperOrigin-RevId: 315604825
Support in other filesystem impls is still needed. Unlike in Linux and vfs1, we
need to plumb inotify down to each filesystem implementation in order to keep
track of links/inode structures properly.
IN_EXCL_UNLINK still needs to be implemented, as well as a few inotify hooks
that are not present in either vfs1 or vfs2. Those will be addressed in
subsequent changes.
Updates #1479.
PiperOrigin-RevId: 313781995
Dean Deng
Adin Scannell
Nayana Bidari
Zach Koopmans
Fabricio Voznika