Currently, there is an attempt to print FD flags, but
they are not decoded into a number, so we see something like this:
/criu # cat /proc/self/fdinfo/0
flags: {%!o(bool=000false)}
Actually, fdinfo has to contain file flags.
Change-Id: Idcbb7db908067447eb9ae6f2c3cfb861f2be1a97
PiperOrigin-RevId: 206794498
We have been unnecessarily creating too many savable types implicitly.
PiperOrigin-RevId: 206334201
Change-Id: Idc5a3a14bfb7ee125c4f2bb2b1c53164e46f29a8
When copying-up files from a lower fs to an upper, we also copy the extended
attributes on the file. If there is a (nested) overlay inside the lower, some
of these extended attributes configure the lower overlay, and should not be
copied-up to the upper.
In particular, whiteout attributes in the lower fs overlay should not be
copied-up, since the upper fs may actually contain the file.
PiperOrigin-RevId: 206236010
Change-Id: Ia0454ac7b99d0e11383f732a529cb195ed364062
The current revalidation logic is very simple and does not do much
introspection of the dirent being revalidated (other than looking at the type
of file).
Fancier revalidation logic is coming soon, and we need to be able to look at
the cached and uncached attributes of a given dirent, and we need a context to
perform some of these operations.
PiperOrigin-RevId: 205307351
Change-Id: If17ea1c631d8f9489c0e05a263e23d7a8a3bf159
In the general case with an overlay, all mmap calls must go through the
overlay, because in the event of a copy-up, the overlay needs to invalidate any
previously-created mappings.
If there if no lower file, however, there will never be a copy-up, so the
overlay can delegate directly to the upper file in that case.
This also allows us to correctly mmap /dev/zero when it is in an overlay. This
file has special semantics which the overlay does not know about. In
particular, it does not implement Mappable(), which (in the general case) the
overlay uses to detect if a file is mappable or not.
PiperOrigin-RevId: 205306743
Change-Id: I92331649aa648340ef6e65411c2b42c12fa69631
Dirent.FullName takes the global renameMu, but can be called during Create,
which itself takes dirent.mu and dirent.dirMu, which is a lock-order violation:
Dirent.Create
d.dirMu.Lock
d.mu.Lock
Inode.Create
gofer.inodeOperations.Create
gofer.NewFile
Dirent.FullName
d.renameMu.RLock
We only use the FullName here for logging, and in this case we can get by with
logging only the BaseName.
A `BaseName` method was added to Dirent, which simply returns the name, taking
d.parent.mu as required.
In the Create pathway, we can't call d.BaseName() because taking d.parent.mu
after d.mu violates the lock order. But we already know the base name of the
file we just created, so that's OK.
In the Open/GetFile pathway, we are free to call d.BaseName() because the other
dirent locks are not held.
PiperOrigin-RevId: 205112278
Change-Id: Ib45c734081aecc9b225249a65fa8093eb4995f10
Per the doc, usage must be kept maximally merged. Beyond that, it is simply a
good idea to keep fragmentation in usage to a minimum.
The glibc malloc allocator allocates one page at a time, potentially causing
lots of fragmentation. However, those pages are likely to have the same number
of references, often making it possible to merge ranges.
PiperOrigin-RevId: 204960339
Change-Id: I03a050cf771c29a4f05b36eaf75b1a09c9465e14
This method allows an eventfd inside the Sentry to be registered with with
the host kernel.
Update comment about memory mapping host fds via CachingInodeOperations.
PiperOrigin-RevId: 204784859
Change-Id: I55823321e2d84c17ae0f7efaabc6b55b852ae257
Otherwise required and optional can be empty or have negative length.
PiperOrigin-RevId: 204007079
Change-Id: I59e472a87a8caac11ffb9a914b8d79bf0cd70995
Updated how restoring occurs through boot.go with a separate Restore function.
This prevents a new process and new mounts from being created.
Added tests to ensure the container is restored.
Registered checkpoint and restore commands so they can be used.
Docker support for these commands is still limited.
Working on #80.
PiperOrigin-RevId: 202710950
Change-Id: I2b893ceaef6b9442b1ce3743bd112383cb92af0c
FIOASYNC and friends are used to send signals when a file is ready for IO.
This may or may not be needed by Nginx. While Nginx does use it, it is unclear
if the code that uses it has any effect.
PiperOrigin-RevId: 201550828
Change-Id: I7ba05a7db4eb2dfffde11e9bd9a35b65b98d7f50
The new policy is identical to FSCACHE (which caches everything in memory), but
it also flushes writes to the backing fs agent immediately.
All gofer cache policy decisions have been moved into the cachePolicy type.
Previously they were sprinkled around the codebase.
There are many different things that we cache (page cache, negative dirents,
dirent LRU, unstable attrs, readdir results....), and I don't think we should
have individual flags to control each of these. Instead, we should have a few
high-level cache policies that are consistent and useful to users. This
refactoring makes it easy to add more such policies.
PiperOrigin-RevId: 201206937
Change-Id: I6e225c382b2e5e1b0ad4ccf8ca229873f4cd389d
Boot loader tries to stat mount to determine whether it's a file or not. This
may file if the sandbox process doesn't have access to the file. Instead, add
overlay on top of file, which is better anyway since we don't want to propagate
changes to the host.
PiperOrigin-RevId: 200411261
Change-Id: I14222410e8bc00ed037b779a1883d503843ffebb
This is the first iteration of checkpoint that actually saves to a file.
Tests for checkpoint are included.
Ran into an issue when private unix sockets are enabled. An error message
was added for this case and the mutex state was set.
PiperOrigin-RevId: 200269470
Change-Id: I28d29a9f92c44bf73dc4a4b12ae0509ee4070e93
Minor refactor. line_discipline.go was home to 2 large structs (lineDiscipline
and queue), and queue is now large enough IMO to get its own file.
Also moves queue locks into the queue struct, making locking simpler.
PiperOrigin-RevId: 200080301
Change-Id: Ia75a0e9b3d9ac8d7e5a0f0099a54e1f5b8bdea34
Adds support for echo to terminals. Echoing is just copying input back out to
the user, e.g. when I type "foo" into a terminal, I expect "foo" to be echoed
back to my terminal.
Also makes the transform function part of the queue, eliminating the need to
pass them around together and the possibility of using the wrong transform for a
queue.
PiperOrigin-RevId: 199655147
Change-Id: I37c490d4fc1ee91da20ae58ba1f884a5c14fd0d8
This change will add support for /proc/sys/net and /proc/net which will
be managed and owned by rpcinet. This will allow these inodes to be forward
as rpcs.
PiperOrigin-RevId: 199370799
Change-Id: I2c876005d98fe55dd126145163bee5a645458ce4
When doing a BidirectionalConnect we don't need to continue holding
the ConnectingEndpoint's mutex when creating the NewConnectedEndpoint
as it was held during the Connect. Additionally, we're not holding
the baseEndpoint mutex while Unregistering an event.
PiperOrigin-RevId: 196875557
Change-Id: Ied4ceed89de883121c6cba81bc62aa3a8549b1e9
Previously, inet.Stack was referenced in 2 structs in sentry/socket that can be
saved/restored. If an app is saved and restored on another machine, it may try
to use the old stack, which will have been replaced by a new stack on the new
machine.
PiperOrigin-RevId: 196733985
Change-Id: I6a8cfe73b5d7a90749734677dada635ab3389cb9
When file is backed by host FD, atime and mtime for the host file and the
cached attributes in the Sentry must be close together. In this case,
the call to update atime and mtime can be skipped. This is important when
host filesystem is using overlay because updating atime and mtime explicitly
forces a copy up for every file that is touched.
PiperOrigin-RevId: 196176413
Change-Id: I3933ea91637a071ba2ea9db9d8ac7cdba5dc0482
Zhaozhong Ni
Andrei Vagin
Justine Olshan
Nicolas Lacasse
Kevin Krakauer
Michael Pratt
Neel Natu
Jamie Liu
Rahat Mahmood
Fabricio Voznika
Ian Gudger
Brielle Broder
Brian Geffon