Initialized BUILD with license
Mount is still unimplemented and is not meant to be
part of this CL. Rest of the fs interface is implemented.
Referenced the Linux kernel appropriately when needed
PiperOrigin-RevId: 249741997
Change-Id: Id1e4c7c9e68b3f6946da39896fc6a0c3dcd7f98c
Separate MountSource from Mount. This is needed to allow
mounts to be shared by multiple containers within the same
pod.
PiperOrigin-RevId: 249617810
Change-Id: Id2944feb7e4194951f355cbe6d4944ae3c02e468
The previous commit adds WNOTHREAD support to waitid, so we may as well
complete the upstream change.
Linux added WCLONE, WALL, WNOTHREAD support to waitid(2) in
91c4e8ea8f05916df0c8a6f383508ac7c9e10dba ("wait: allow sys_waitid() to
accept __WNOTHREAD/__WCLONE/__WALL"). i.e., Linux 4.7.
PiperOrigin-RevId: 249560587
Change-Id: Iff177b0848a3f7bae6cb5592e44500c5a942fbeb
There no obvious reason to require that BlockSize and StatFS
are MountSource operations. Today they are in INodeOperations,
and they can be moved elsewhere in the future as part of a
normal refactor process.
PiperOrigin-RevId: 249549982
Change-Id: Ib832e02faeaf8253674475df4e385bcc53d780f3
Pipe internals are made more efficient by avoiding garbage collection.
A pool is now used that can be shared by all pipes, and buffers are
chained via an intrusive list. The documentation for pipe structures
and methods is also simplified and clarified.
The pipe tests are now parameterized, so that they are run on all
different variants (named pipes, small buffers, default buffers).
The pipe buffer sizes are exposed by fcntl, which is now supported
by this change. A size change test has been added to the suite.
These new tests uncovered a bug regarding the semantics of open
named pipes with O_NONBLOCK, which is also fixed by this CL. This
fix also addresses the lack of the O_LARGEFILE flag for named pipes.
PiperOrigin-RevId: 249375888
Change-Id: I48e61e9c868aedb0cadda2dff33f09a560dee773
* A segment with filesz == 0, memsz > 0 should be an anonymous only
mapping. We were failing to load such an ELF.
* Anonymous pages are always mapped RW, regardless of the segment
protections.
PiperOrigin-RevId: 249355239
Change-Id: I251e5c0ce8848cf8420c3aadf337b0d77b1ad991
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
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
* Creation of files, directories (and other fs objects) in a directory
should always update ctime.
* Same for removal.
* atime should not be updated on lookup, only readdir.
I've also renamed some misleading functions that update mtime and ctime.
PiperOrigin-RevId: 249115063
Change-Id: I30fa275fa7db96d01aa759ed64628c18bb3a7dc7
There is a lot of redundancy that we can simplify in the stat_times
test. This will make it easier to add new tests. However, the
simplification reveals that cached uattrs on goferfs don't properly
update ctime on rename.
PiperOrigin-RevId: 248773425
Change-Id: I52662728e1e9920981555881f9a85f9ce04041cf
And stop storing the Filesystem in the MountSource.
This allows us to decouple the MountSource filesystem type from the name of the
filesystem.
PiperOrigin-RevId: 247292982
Change-Id: I49cbcce3c17883b7aa918ba76203dfd6d1b03cc8
This feature allows MemoryFile to delay eviction of "optional"
allocations, such as unused cached file pages.
Note that this incidentally makes CachingInodeOperations writeback
asynchronous, in the sense that it doesn't occur until eviction; this is
necessary because between when a cached page becomes evictable and when
it's evicted, file writes (via CachingInodeOperations.Write) may dirty
the page.
As currently implemented, this feature won't meaningfully impact
steady-state memory usage or caching; the reclaimer goroutine will
schedule eviction as soon as it runs out of other work to do. Future CLs
increase caching by adding constraints on when eviction is scheduled.
PiperOrigin-RevId: 246014822
Change-Id: Ia85feb25a2de92a48359eb84434b6ec6f9bea2cb
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
Previously, createAt was eating all errors from FindInode except for EACCES and
proceeding with the creation. This is incorrect, as FindInode can return many
other errors (like ENAMETOOLONG) that should stop creation.
This CL changes createAt to return all errors encountered except for ENOENT,
which we can ignore because we are about to create the thing.
PiperOrigin-RevId: 245773222
Change-Id: I1b317021de70f0550fb865506f6d8147d4aebc56
Maximum filename length is filesystem-dependent, and obtained via
statfs::f_namelen. This limit is usually 255 bytes (NAME_MAX), but not
always. For example, VFAT supports filenames of up to 255... UCS-2
characters, which Linux conservatively takes to mean UTF-8-encoded
bytes: fs/fat/inode.c:fat_statfs(), FAT_LFN_LEN * NLS_MAX_CHARSET_SIZE.
As a result, Linux's VFS does not enforce NAME_MAX:
$ rg --maxdepth=1 '\WNAME_MAX\W' fs/ include/linux/
fs/libfs.c
38: buf->f_namelen = NAME_MAX;
64: if (dentry->d_name.len > NAME_MAX)
include/linux/relay.h
74: char base_filename[NAME_MAX]; /* saved base filename */
include/linux/fscrypt.h
149: * filenames up to NAME_MAX bytes, since base64 encoding expands the length.
include/linux/exportfs.h
176: * understanding that it is already pointing to a a %NAME_MAX+1 sized
Remove this check from core VFS, and add it to ramfs (and by extension
tmpfs), where it is actually applicable:
mm/shmem.c:shmem_dir_inode_operations.lookup == simple_lookup *does*
enforce NAME_MAX.
PiperOrigin-RevId: 245324748
Change-Id: I17567c4324bfd60e31746a5270096e75db963fac
For a symbol link to some directory, eg.
`/tmp/symlink -> /tmp/dir`
`fstatat("/tmp/symlink")` should return symbol link data, but
`fstatat("/tmp/symlink/")` (symlink with trailing slash) should return
directory data it points following linux behaviour.
Currently fstatat() a symlink with trailing slash will get "not a
directory" error which is wrong.
Signed-off-by: Wei Zhang <zhangwei198900@gmail.com>
Change-Id: I63469b1fb89d083d1c1255d32d52864606fbd7e2
PiperOrigin-RevId: 244783916
The MSG_TRUNC flag is set in the msghdr when a message is truncated.
Fixesgoogle/gvisor#200
PiperOrigin-RevId: 244440486
Change-Id: I03c7d5e7f5935c0c6b8d69b012db1780ac5b8456
Only emit unimplemented syscall events for setting SO_OOBINLINE and SO_LINGER
when attempting to set unsupported values.
PiperOrigin-RevId: 244229675
Change-Id: Icc4562af8f733dd75a90404621711f01a32a9fc1
The existing logic attempting to do this is incorrect. Unary ^ has
higher precedence than &^, so mask always has UnblockableSignals
cleared, allowing dequeueSignalLocked to dequeue unblockable signals
(which allows userspace to ignore them).
Switch the logic so that unblockable signals are always masked.
PiperOrigin-RevId: 244058487
Change-Id: Ib19630ac04068a1fbfb9dc4a8eab1ccbdb21edc3
FD limit and file size limit is read from the host, instead
of using hard-coded defaults, given that they effect the sandbox
process. Also limit the direct cache to use no more than half
if the available FDs.
PiperOrigin-RevId: 244050323
Change-Id: I787ad0fdf07c49d589e51aebfeae477324fe26e6
Current, doPoll copies the user struct pollfd array into a
[]syscalls.PollFD, which contains internal kdefs.FD and
waiter.EventMask types. While these are currently binary-compatible with
the Linux versions, we generally discourage copying directly to internal
types (someone may inadvertantly change kdefs.FD to uint64).
Instead, copy directly to a []linux.PollFD, which will certainly be
binary compatible. Most of syscalls/polling.go is included directly into
syscalls/linux/sys_poll.go, as it can then operate directly on
linux.PollFD. The additional syscalls.PollFD type is providing little
value.
I've also added explicit conversion functions for waiter.EventMask,
which creates the possibility of a different binary format.
PiperOrigin-RevId: 244042947
Change-Id: I24e5b642002a32b3afb95a9dcb80d4acd1288abf
Normal files display their path in the current mount namespace:
I0410 10:57:54.964196 216336 x:0] [ 1] ls X read(0x3 /proc/filesystems, 0x55cee3bdb2c0 "nodev\t9p\nnodev\tdevpts \nnodev\tdevtmpfs\nnodev\tproc\nnodev\tramdiskfs\nnodev\tsysfs\nnodev\ttmpfs\n", 0x1000) = 0x58 (24.462?s)
AT_FDCWD includes the CWD:
I0411 12:58:48.278427 1526 x:0] [ 1] stat_test E newfstatat(AT_FDCWD /home/prattmic, 0x55ea719b564e /proc/self, 0x7ef5cefc2be8, 0x0)
Sockets (and other non-vfs files) display an inode number (like
/proc/PID/fd):
I0410 10:54:38.909123 207684 x:0] [ 1] nc E bind(0x3 socket:[1], 0x55b5a1652040 {Family: AF_INET, Addr: , Port: 8080}, 0x10)
I also fixed a few syscall args that should be Path.
PiperOrigin-RevId: 243169025
Change-Id: Ic7dda6a82ae27062fe2a4a371557acfd6a21fa2a
RootFromContext can return a dirent with reference taken, or nil. We must call
DecRef if (and only if) a real dirent is returned.
PiperOrigin-RevId: 242965515
Change-Id: Ie2b7b4cb19ee09b6ccf788b71f3fd7efcdf35a11