Removes package syserror and moves still relevant code to either linuxerr
or to syserr (to be later removed).
Internal errors are converted from random types to *errors.Error types used
in linuxerr. Internal errors are in linuxerr/internal.go.
PiperOrigin-RevId: 390724202
Update all instances of the above errors to the faster linuxerr implementation.
With the temporary linuxerr.Equals(), no logical changes are made.
PiperOrigin-RevId: 382306655
Remove three syserror entries duplicated in linuxerr. Because of the
linuxerr.Equals method, this is a mere change of return values from
syserror to linuxerr definitions.
Done with only these three errnos as CLs removing all grow to a significantly
large size.
PiperOrigin-RevId: 382173835
- Remove the pipe package's dependence on the buffer package, which becomes
unused as a result. The buffer package is currently intended to serve two use
cases, pipes and temporary buffers, and does neither optimally as a result;
this change facilitates retooling the buffer package to better serve the
latter.
- Pass callbacks taking safemem.BlockSeq to the internal pipe I/O methods,
which makes most callbacks trivial.
- Fix VFS1's splice() and tee() to immediately return if a pipe returns a
partial write.
PiperOrigin-RevId: 351911375
Writes to pipes of size < PIPE_BUF are guaranteed to be atomic, so writes
larger than that will return EAGAIN if the pipe has capacity < PIPE_BUF.
Writes to eventfds will return EAGAIN if the write would cause the eventfd
value to go over the max.
In both such cases, calling Ready() on the FD will return true (because it is
possible to write), but specific kinds of writes will in fact return EAGAIN.
This CL fixes an infinite loop in splice and sendfile (VFS1 and VFS2) by
forcing skipping the readiness check for the outfile in send, splice, and tee.
PiperOrigin-RevId: 341102260
Splice, setxattr and removexattr should generate events. Note that VFS2 already
generates events for extended attributes.
Updates #1479.
PiperOrigin-RevId: 314244261
Splice must not allow negative offsets. Writes also must not allow offset +
size to overflow int64. Reads are similarly broken, but not just in splice
(b/148095030).
Reported-by: syzbot+0e1ff0b95fb2859b4190@syzkaller.appspotmail.com
PiperOrigin-RevId: 292361208
Special files can have additional requirements for granularity.
For example, read from eventfd returns EINVAL if a size is less 8 bytes.
Reported-by: syzbot+3905f5493bec08eb7b02@syzkaller.appspotmail.com
PiperOrigin-RevId: 292002926
The input file descriptor is always a regular file, so sendfile can't lose any
data if it will not be able to write them to the output file descriptor.
Reported-by: syzbot+22d22330a35fa1c02155@syzkaller.appspotmail.com
PiperOrigin-RevId: 272730357
It isn't allowed to splice data from and into the same pipe.
But right now this check is broken, because we don't check that both ends are
pipes.
PiperOrigin-RevId: 272107022
This also allows the tee(2) implementation to be enabled, since dup can now be
properly supported via WriteTo.
Note that this change necessitated some minor restructoring with the
fs.FileOperations splice methods. If the *fs.File is passed through directly,
then only public API methods are accessible, which will deadlock immediately
since the locking is already done by fs.Splice. Instead, we pass through an
abstract io.Reader or io.Writer, which elide locks and use the underlying
fs.FileOperations directly.
PiperOrigin-RevId: 268805207
This renames FDMap to FDTable and drops the kernel.FD type, which had an entire
package to itself and didn't serve much use (it was freely cast between types,
and served as more of an annoyance than providing any protection.)
Based on BenchmarkFDLookupAndDecRef-12, we can expect 5-10 ns per lookup
operation, and 10-15 ns per concurrent lookup operation of savings.
This also fixes two tangential usage issues with the FDMap. Namely, non-atomic
use of NewFDFrom and associated calls to Remove (that are both racy and fail to
drop the reference on the underlying file.)
PiperOrigin-RevId: 256285890
The sendfile syscall's backing doSplice contained a race with regard to
blocking. If the first attempt failed with syserror.ErrWouldBlock and then
the blocking file became ready before registering a waiter, we would just
return the ErrWouldBlock (even if we were supposed to block).
PiperOrigin-RevId: 254114432
This does not actually implement an efficient splice or sendfile. Rather, it
adds a generic plumbing to the file internals so that this can be added. All
file implementations use the stub fileutil.NoSplice implementation, which
causes sendfile and splice to fall back to an internal copy.
A basic splice system call interface is added, along with a test.
PiperOrigin-RevId: 249335960
Change-Id: Ic5568be2af0a505c19e7aec66d5af2480ab0939b
Currently the implementation matches the behavior of moving data
between two file descriptors. However, it does not implement this
through zero-copy movement. Thus, this code is a starting point
to build the more complex implementation.
PiperOrigin-RevId: 208284483
Change-Id: Ibde79520a3d50bc26aead7ad4f128d2be31db14e
Zach Koopmans
Jamie Liu
Nicolas Lacasse
Rahat Mahmood
Dean Deng
Nayana Bidari
Bhasker Hariharan
Andrei Vagin
Michael Pratt
Adin Scannell
Fabricio Voznika
Ian Gudger
Justine Olshan