Current procfs has some bugs. After executing ls twice, many dirs come
out with same name like "1" or ".". Files like "cpuinfo" disappear.
Here variable names is a slice with cap() > len(). Sort after appending
to it will not alloc a new space and impact orignal slice. Same to m.
Signed-off-by: Ruidong Cao <crdfrank@gmail.com>
Change-Id: I83e5cd1c7968c6fe28c35ea4fee497488d4f9eef
PiperOrigin-RevId: 236222270
In addition to simplifying the implementation, this fixes two bugs:
- seqfile.NewSeqFile unconditionally creates an inode with mode 0444,
but {uid,gid}_map have mode 0644.
- idMapSeqFile.Write implements fs.FileOperations.Write ... but it
doesn't implement any other fs.FileOperations methods and is never
used as fs.FileOperations. idMapSeqFile.GetFile() =>
seqfile.SeqFile.GetFile() uses seqfile.seqFileOperations instead,
which rejects all writes.
PiperOrigin-RevId: 234638212
Change-Id: I4568f741ab07929273a009d7e468c8205a8541bc
If a background process tries to read from a TTY, linux sends it a SIGTTIN
unless the signal is blocked or ignored, or the process group is an orphan, in
which case the syscall returns EIO.
See drivers/tty/n_tty.c:n_tty_read()=>job_control().
If a background process tries to write a TTY, set the termios, or set the
foreground process group, linux then sends a SIGTTOU. If the signal is ignored
or blocked, linux allows the write. If the process group is an orphan, the
syscall returns EIO.
See drivers/tty/tty_io.c:tty_check_change().
PiperOrigin-RevId: 234044367
Change-Id: I009461352ac4f3f11c5d42c43ac36bb0caa580f9
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
- Change proc to return envp on overwrite of argv with limitations from
upstream.
- Add unit tests
- Change layout of argv/envp on the stack so that end of argv is contiguous with
beginning of envp.
PiperOrigin-RevId: 232506107
Change-Id: I993880499ab2c1220f6dc456a922235c49304dec
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
Nothing reads them and they can simply get stale.
Generated with:
$ sed -i "s/licenses(\(.*\)).*/licenses(\1)/" **/BUILD
PiperOrigin-RevId: 231818945
Change-Id: Ibc3f9838546b7e94f13f217060d31f4ada9d4bf0
We were modifying InodeSimpleAttributes.Unstable.AccessTime without holding
the necessary lock. Luckily for us, InodeSimpleAttributes already has a
NotifyAccess method that will do the update while holding the lock.
In addition, we were holding dfo.dir.mu.Lock while setting AccessTime, which
is unnecessary, so that lock has been removed.
PiperOrigin-RevId: 231278447
Change-Id: I81ed6d3dbc0b18e3f90c1df5e5a9c06132761769
It never actually should have applied to environ (the relevant change in
Linux 4.2 is c2c0bb44620d "proc: fix PAGE_SIZE limit of
/proc/$PID/cmdline"), and we claim to be Linux 4.4 now anyway.
PiperOrigin-RevId: 231250661
Change-Id: I37f9c4280a533d1bcb3eebb7803373ac3c7b9f15
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
Most of the entries are stubbed out at the moment, but even those were
only displayed if IPv6 support was enabled. The entries should be
displayed with IPv4-support only, and with only loopback devices.
PiperOrigin-RevId: 229946441
Change-Id: I18afaa3af386322787f91bf9d168ab66c01d5a4c
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
overlayFileOperations.Readdir was holding overlay.copyMu while calling
DirentReaddir, which then attempts to take take the corresponding Dirent.mu,
causing a lock order violation. (See lock order documentation in
fs/copy_up.go.)
We only actually need to hold copyMu during readdirEntries(), so holding the
lock is moved in there, thus avoiding the lock order violation.
A new lock was added to protect overlayFileOperations.dirCache. We were
inadvertently relying on copyMu to protect this. There is no reason it should
not have its own lock.
PiperOrigin-RevId: 228542473
Change-Id: I03c3a368c8cbc0b5a79d50cc486fc94adaddc1c2
epoll_wait acquires EventPoll.listsMu (in EventPoll.ReadEvents) and
then calls Inotify.Readiness which tries to acquire Inotify.evMu.
getdents acquires Inotify.evMu (in Inotify.queueEvent) and then calls
readyCallback.Callback which tries to acquire EventPoll.listsMu.
The fix is to release Inotify.evMu before calling Queue.Notify. Queue
is thread-safe and doesn't require Inotify.evMu to be held.
Closes#121
PiperOrigin-RevId: 227066695
Change-Id: Id29364bb940d1727f33a5dff9a3c52f390c15761
The code that matches the event being published with events watchers
was wronly matching all watchers in case any of the control event bits
were set.
Issue #121
PiperOrigin-RevId: 226521230
Change-Id: Ie2c42bc4366faaf59fbf80a74e9297499bd93f9e
We must wait for all lazy resources to be released before closing the rootFile.
PiperOrigin-RevId: 226419499
Change-Id: I1d4d961a92b3816e02690cf3eaf0a88944d730cc
The old overlayBoundEndpoint assumed that the lower is not an overlay. It
should check if the lower is an overlay and handle that case.
PiperOrigin-RevId: 225882303
Change-Id: I60660c587d91db2826e0719da0983ec8ad024cb8
Platform objects are not savable, storing references to them in
filesystem datastructures would cause save to fail if someone actually
passed in a Platform.
Current implementations work because everywhere a Platform is
expected, we currently pass in a Kernel object which embeds Platform
and thus satisfies the interface.
Eliminate this indirection and save pointers to Kernel directly.
PiperOrigin-RevId: 225288336
Change-Id: Ica399ff43f425e15bc150a0d7102196c3d54a2ab
MSG_WAITALL requests that recv family calls do not perform short reads. It only
has an effect for SOCK_STREAM sockets, other types ignore it.
PiperOrigin-RevId: 224918540
Change-Id: Id97fbf972f1f7cbd4e08eec0138f8cbdf1c94fe7
By Walking before checking that the directory is writable and
executable, MayDelete may return the Walk error (e.g., ENOENT) which
would normally be masked by a permission error (EACCES).
PiperOrigin-RevId: 224222453
Change-Id: I108a7f730e6bdaa7f277eaddb776267c00805475
The number of symbolic links that are allowed to be followed
are for a full path and not just a chain of symbolic links.
PiperOrigin-RevId: 224047321
Change-Id: I5e3c4caf66a93c17eeddcc7f046d1e8bb9434a40
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