Commit Graph

9 Commits

Author SHA1 Message Date
Jamie Liu dc029b4b96 Implement VFS2 tmpfs mount options.
As in VFS1, the mode, uid, and gid options are supported.

Updates #1197

PiperOrigin-RevId: 315340510
2020-06-08 13:28:18 -07:00
Dean Deng ccf69bdd7e Implement IN_EXCL_UNLINK inotify option in vfs2.
Limited to tmpfs. Inotify support in other filesystem implementations to
follow.

Updates #1479

PiperOrigin-RevId: 313828648
2020-05-29 12:28:49 -07:00
Dean Deng fe464f44b7 Port inotify to vfs2, with support in tmpfs.
Support in other filesystem impls is still needed. Unlike in Linux and vfs1, we
need to plumb inotify down to each filesystem implementation in order to keep
track of links/inode structures properly.

IN_EXCL_UNLINK still needs to be implemented, as well as a few inotify hooks
that are not present in either vfs1 or vfs2. Those will be addressed in
subsequent changes.

Updates #1479.

PiperOrigin-RevId: 313781995
2020-05-29 08:09:14 -07:00
Jamie Liu 9b5e305e05 Remove filesystem structure from vfs.Dentry.
This change:

- Drastically simplifies the synchronization model: filesystem structure is
  both implementation-defined and implementation-synchronized.

- Allows implementations of vfs.DentryImpl to use implementation-specific
  dentry types, reducing casts during path traversal.

- Doesn't require dentries representing non-directory files to waste space on a
  map of children.

- Allows dentry revalidation and mount lookup to be correctly ordered (fixed
  FIXME in fsimpl/gofer/filesystem.go).

- Removes the need to have two separate maps in gofer.dentry
  (dentry.vfsd.children and dentry.negativeChildren) for positive and negative
  lookups respectively.

//pkg/sentry/fsimpl/tmpfs/benchmark_test.go:
name                        old time/op  new time/op  delta
VFS2TmpfsStat/1-112          172ns ± 4%   165ns ± 3%   -4.08%  (p=0.002 n=9+9)
VFS2TmpfsStat/2-112          199ns ± 3%   195ns ±10%     ~     (p=0.132 n=8+9)
VFS2TmpfsStat/3-112          230ns ± 2%   216ns ± 2%   -6.15%  (p=0.000 n=8+8)
VFS2TmpfsStat/8-112          390ns ± 2%   358ns ± 4%   -8.33%  (p=0.000 n=9+8)
VFS2TmpfsStat/64-112        2.20µs ± 3%  2.01µs ± 3%   -8.48%  (p=0.000 n=10+8)
VFS2TmpfsStat/100-112       3.42µs ± 9%  3.08µs ± 2%   -9.82%  (p=0.000 n=9+8)
VFS2TmpfsMountStat/1-112     278ns ± 1%   286ns ±15%     ~     (p=0.712 n=8+10)
VFS2TmpfsMountStat/2-112     311ns ± 4%   298ns ± 2%   -4.27%  (p=0.000 n=9+8)
VFS2TmpfsMountStat/3-112     339ns ± 3%   330ns ± 9%     ~     (p=0.070 n=8+9)
VFS2TmpfsMountStat/8-112     503ns ± 3%   466ns ± 3%   -7.38%  (p=0.000 n=8+8)
VFS2TmpfsMountStat/64-112   2.53µs ±16%  2.17µs ± 7%  -14.19%  (p=0.000 n=10+9)
VFS2TmpfsMountStat/100-112  3.60µs ± 4%  3.30µs ± 8%   -8.33%  (p=0.001 n=8+9)

Updates #1035

PiperOrigin-RevId: 307655892
2020-04-21 12:18:07 -07:00
Fabricio Voznika dd3bc49997 Add NAME_MAX checks and update file times
NAME_MAX should be enforced per filesystem implementation
because other file systems may not have the same restriction.

Gofer filesystem now keeps a reference to the kernel clock to
avoid lookup in the Context on file access to update atime.

Update access, modification, and status change times in tmpfs.

Updates #1197, #1198.

PiperOrigin-RevId: 304527148
2020-04-02 19:39:03 -07:00
Fabricio Voznika c7f5673529 Set file mode and type to attribute
Makes less error prone to find file type.

Updates #1197

PiperOrigin-RevId: 302974244
2020-03-25 14:49:13 -07:00
gVisor bot 3557b26651 Allow vfs.IterDirentsCallback.Handle() to return an error.
This is easier than storing errors from e.g. CopyOut in the callback.

PiperOrigin-RevId: 295230021
2020-02-14 14:40:35 -08:00
Adin Scannell 0e2f1b7abd Update package locations.
Because the abi will depend on the core types for marshalling (usermem,
context, safemem, safecopy), these need to be flattened from the sentry
directory. These packages contain no sentry-specific details.

PiperOrigin-RevId: 291811289
2020-01-27 15:31:32 -08:00
Nicolas Lacasse 51f3ab85e0 Convert memfs into proto-tmpfs.
- Renamed memfs to tmpfs.
- Copied fileRangeSet bits from fs/fsutil/ to fsimpl/tmpfs/
- Changed tmpfs to be backed by filemem instead of byte slice.
- regularFileReadWriter uses a sync.Pool, similar to gofer client.

PiperOrigin-RevId: 288356380
2020-01-06 12:52:55 -08:00