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2019-11-18Add vfs.GenericParseMountOptions().Jamie Liu
Equivalent to fs.GenericMountSourceOptions(). PiperOrigin-RevId: 281179287
2019-10-29Update build tags to allow Go 1.14Michael Pratt
Currently there are no ABI changes. We should check again closer to release. PiperOrigin-RevId: 277349744
2019-10-19Add support for pipes in VFS2.Kevin Krakauer
PiperOrigin-RevId: 275650307
2019-10-15Minor vfs.FileDescriptionImpl fixes.Jamie Liu
- Pass context.Context to OnClose(). - Pass memmap.MMapOpts to ConfigureMMap() by pointer so that implementations can actually mutate it as required. PiperOrigin-RevId: 274934967
2019-10-04Change linux.FileMode from uint to uint16, and update VFS to use FileMode.Kevin Krakauer
In Linux (include/linux/types.h), mode_t is an unsigned short. PiperOrigin-RevId: 272956350
2019-09-20Change vfs.Dirent.Off to NextOff.Jamie Liu
"d_off is the distance from the start of the directory to the start of the next linux_dirent." - getdents(2). PiperOrigin-RevId: 270349685
2019-09-12Remove go_test from go_stateify and go_marshalMichael Pratt
They are no-ops, so the standard rule works fine. PiperOrigin-RevId: 268776264
2019-08-16vfs: Remove vfs.DefaultDirectoryFD from embedding vfs.DefaultFD.Ayush Ranjan
This fixes the implementation ambiguity issues when a filesystem implementation embeds vfs.DefaultDirectoryFD to its directory FD along with an internal common fileDescription utility. For similar reasons also removes FileDescriptionDefaultImpl from DynamicBytesFileDescriptionImpl. PiperOrigin-RevId: 263795513
2019-08-13Add vfs.DynamicBytesFileDescriptionImpl.Jamie Liu
This replaces fs/proc/seqfile for vfs2-based filesystems. PiperOrigin-RevId: 263254647
2019-07-18Sentry virtual filesystem, v2Jamie Liu
Major differences from the current ("v1") sentry VFS: - Path resolution is Filesystem-driven (FilesystemImpl methods call vfs.ResolvingPath methods) rather than VFS-driven (fs package owns a Dirent tree and calls fs.InodeOperations methods to populate it). This drastically improves performance, primarily by reducing overhead from inefficient synchronization and indirection. It also makes it possible to implement remote filesystem protocols that translate FS system calls into single RPCs, rather than having to make (at least) one RPC per path component, significantly reducing the latency of remote filesystems (especially during cold starts and for uncacheable shared filesystems). - Mounts are correctly represented as a separate check based on contextual state (current mount) rather than direct replacement in a fs.Dirent tree. This makes it possible to support (non-recursive) bind mounts and mount namespaces. Included in this CL is fsimpl/memfs, an incomplete in-memory filesystem that exists primarily to demonstrate intended filesystem implementation patterns and for benchmarking: BenchmarkVFS1TmpfsStat/1-6 3000000 497 ns/op BenchmarkVFS1TmpfsStat/2-6 2000000 676 ns/op BenchmarkVFS1TmpfsStat/3-6 2000000 904 ns/op BenchmarkVFS1TmpfsStat/8-6 1000000 1944 ns/op BenchmarkVFS1TmpfsStat/64-6 100000 14067 ns/op BenchmarkVFS1TmpfsStat/100-6 50000 21700 ns/op BenchmarkVFS2MemfsStat/1-6 10000000 197 ns/op BenchmarkVFS2MemfsStat/2-6 5000000 233 ns/op BenchmarkVFS2MemfsStat/3-6 5000000 268 ns/op BenchmarkVFS2MemfsStat/8-6 3000000 477 ns/op BenchmarkVFS2MemfsStat/64-6 500000 2592 ns/op BenchmarkVFS2MemfsStat/100-6 300000 4045 ns/op BenchmarkVFS1TmpfsMountStat/1-6 2000000 679 ns/op BenchmarkVFS1TmpfsMountStat/2-6 2000000 912 ns/op BenchmarkVFS1TmpfsMountStat/3-6 1000000 1113 ns/op BenchmarkVFS1TmpfsMountStat/8-6 1000000 2118 ns/op BenchmarkVFS1TmpfsMountStat/64-6 100000 14251 ns/op BenchmarkVFS1TmpfsMountStat/100-6 100000 22397 ns/op BenchmarkVFS2MemfsMountStat/1-6 5000000 317 ns/op BenchmarkVFS2MemfsMountStat/2-6 5000000 361 ns/op BenchmarkVFS2MemfsMountStat/3-6 5000000 387 ns/op BenchmarkVFS2MemfsMountStat/8-6 3000000 582 ns/op BenchmarkVFS2MemfsMountStat/64-6 500000 2699 ns/op BenchmarkVFS2MemfsMountStat/100-6 300000 4133 ns/op From this we can infer that, on this machine: - Constant cost for tmpfs stat() is ~160ns in VFS2 and ~280ns in VFS1. - Per-path-component cost is ~35ns in VFS2 and ~215ns in VFS1, a difference of about 6x. - The cost of crossing a mount boundary is about 80ns in VFS2 (MemfsMountStat/1 does approximately the same amount of work as MemfsStat/2, except that it also crosses a mount boundary). This is an inescapable cost of the separate mount lookup needed to support bind mounts and mount namespaces. PiperOrigin-RevId: 258853946