Based on the guidelines at
https://opensource.google.com/docs/releasing/authors/.
1. $ rg -l "Google LLC" | xargs sed -i 's/Google LLC.*/The gVisor Authors./'
2. Manual fixup of "Google Inc" references.
3. Add AUTHORS file. Authors may request to be added to this file.
4. Point netstack AUTHORS to gVisor AUTHORS. Drop CONTRIBUTORS.
Fixes#209
PiperOrigin-RevId: 245823212
Change-Id: I64530b24ad021a7d683137459cafc510f5ee1de9
- Document fsutil.CachedFileObject.FD() requirements on access
permissions, and change gofer.inodeFileState.FD() to honor them.
Fixes#147.
- Combine gofer.inodeFileState.readonly and
gofer.inodeFileState.readthrough, and simplify handle caching logic.
- Inline gofer.cachePolicy.cacheHandles into
gofer.inodeFileState.setSharedHandles, because users with access to
gofer.inodeFileState don't necessarily have access to the fs.Inode
(predictably, this is a save/restore problem).
Before this CL:
$ docker run --runtime=runsc-d -v $(pwd)/gvisor/repro:/root/repro -it ubuntu bash
root@34d51017ed67:/# /root/repro/runsc-b147
mmap: 0x7f3c01e45000
Segmentation fault
After this CL:
$ docker run --runtime=runsc-d -v $(pwd)/gvisor/repro:/root/repro -it ubuntu bash
root@d3c3cb56bbf9:/# /root/repro/runsc-b147
mmap: 0x7f78987ec000
o
PiperOrigin-RevId: 240818413
Change-Id: I49e1d4a81a0cb9177832b0a9f31a10da722a896b
fs/gofer/inodeOperations.Release does some asynchronous work. Previously it
was calling fs.Async with an anonymous function, which caused the function to
be allocated on the heap. Because Release is relatively hot, this results in a
lot of small allocations and increased GC pressure, noticeable in perf profiles.
This CL adds a new function, AsyncWithContext, which is just like Async, but
passes a context to the async function. It avoids the need for an extra
anonymous function in fs/gofer/inodeOperations.Release. The Async function
itself still requires a single anonymous function.
PiperOrigin-RevId: 233141763
Change-Id: I1dce4a883a7be9a8a5b884db01e654655f16d19c
Dirty should be set only when the attribute is changed in the cache
only. Instances where the change was also sent to the backing file
doesn't need to dirty the attribute.
Also remove size update during WriteOut as writing dirty page would
naturaly grow the file if needed.
RELNOTES: relnotes is needed for the parent CL.
PiperOrigin-RevId: 232068978
Change-Id: I00ba54693a2c7adc06efa9e030faf8f2e8e7f188
This changed required making fsutil.HostMappable use
a backing file to ensure the correct FD would be used
for read/write operations.
RELNOTES: relnotes is needed for the parent CL.
PiperOrigin-RevId: 231836164
Change-Id: I8ae9639715529874ea7d80a65e2c711a5b4ce254
When file size changes outside the sandbox, page cache was not
refreshing file size which is required for cacheRemoteRevalidating.
In fact, cacheRemoteRevalidating should be skipping the cache
completely since it's not really benefiting from it. The cache is
cache is already bypassed for unstable attributes (see
cachePolicy.cacheUAttrs). And althought the cache is called to
map pages, they will always miss the cache and map directly from
the host.
Created a HostMappable struct that maps directly to the host and
use it for files with cacheRemoteRevalidating.
Closes#124
PiperOrigin-RevId: 230998440
Change-Id: Ic5f632eabe33b47241e05e98c95e9b2090ae08fc
More helper structs have been added to the fsutil package to make it easier to
implement fs.InodeOperations and fs.FileOperations.
PiperOrigin-RevId: 229305982
Change-Id: Ib6f8d3862f4216745116857913dbfa351530223b
Replaces the WaitGroup with a RWMutex. Calls to Async hold the mutex for
reading, while AsyncBarrier takes the lock for writing. This ensures that all
executing Async work finishes before AsyncBarrier returns.
Also pushes the Async() call from Inode.Release into
gofer/InodeOperations.Release(). This removes a recursive Async call which
should not have been allowed in the first place. The gofer Release call is the
slow one (since it may make RPCs to the gofer), so putting the Async call there
makes sense.
PiperOrigin-RevId: 223093067
Change-Id: I116da7b20fce5ebab8d99c2ab0f27db7c89d890e
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
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
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
Adin Scannell
Fabricio Voznika
Michael Pratt
Nicolas Lacasse
Jamie Liu
Ian Gudger
Zhaozhong Ni
Googler