This is to cover the common pattern: open->read/write->close,
where SetAttr needs to be called to update atime/mtime before
the file is closed.
Benchmark results:
BM_OpenReadClose/10240 CPU
setattr+clunk: 63783 ns
VFS2: 68109 ns
VFS1: 72507 ns
Updates #1198
PiperOrigin-RevId: 329628461
There was a very bare get/setxattr in the InodeOperations interface. Add
context.Context to both, size to getxattr, and flags to setxattr.
Note that extended attributes are passed around as strings in this
implementation, so size is automatically encoded into the value. Size is
added in getxattr so that implementations can return ERANGE if a value is larger
than can fit in the user-allocated buffer. This prevents us from unnecessarily
passing around an arbitrarily large xattr when the user buffer is actually too
small.
Don't use the existing xattrwalk and xattrcreate messages and define our
own, mainly for the sake of simplicity.
Extended attributes will be implemented in future commits.
PiperOrigin-RevId: 290121300
The backing 9p server must allow named pipe creation, which the runsc
fsgofer currently does not.
There are small changes to the overlay here. GetFile may block when
opening a named pipe, which can cause a deadlock:
1. open(O_RDONLY) -> copyMu.Lock() -> GetFile()
2. open(O_WRONLY) -> copyMu.Lock() -> Deadlock
A named pipe usable for writing must already be on the upper filesystem,
but we are still taking copyMu for write when checking for upper. That
can be changed to a read lock to fix the common case.
However, a named pipe on the lower filesystem would still deadlock in
open(O_WRONLY) when it tries to actually perform copy up (which would
simply return EINVAL). Move the copy up type check before taking copyMu
for write to avoid this.
p9 must be modified, as it was incorrectly removing the file mode when
sending messages on the wire.
PiperOrigin-RevId: 249154033
Change-Id: Id6637130e567b03758130eb6c7cdbc976384b7d6
Cache last used messages and reuse them for subsequent requests.
If more messages are needed, they are created outside the cache
on demand.
PiperOrigin-RevId: 245836910
Change-Id: Icf099ddff95df420db8e09f5cdd41dcdce406c61
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
p9.messageByType was taking 7% of p9.recv before, spending time
with reflection and map lookup. Now it's reduced to 1%.
PiperOrigin-RevId: 244947313
Change-Id: I42813f920557b7656f8b29157eb32acd79e11fa5
Fabricio Voznika
Sevki
Uros Prestor
gVisor bot
Dean Deng
Adin Scannell
Michael Pratt
Ian Gudger
Googler