The suspension helpers are now put into file system specific operations.
This means every file system not supporting these helpers cannot be suspended
and therefore snapshots are no longer possible.
Implemented for file systems of type ffs.
The new API is enabled on a kernel option NEWVNGATE. This option is
not enabled by default in any kernel config.
Presented and discussed on tech-kern with much input from
Bill Studenmund <wrstuden@netbsd.org> and YAMAMOTO Takashi <yamt@netbsd.org>.
Welcome to 4.99.9 (new vfs op vfs_suspendctl).
- LOCKPARENT is no longer relevant for lookup(), relookup() or VOP_LOOKUP().
these now always return the parent vnode locked. namei() works as before.
lookup() and various other paths no longer acquire vnode locks in the
wrong order via vrele(). fixes PR 32535.
as a nice side effect, path lookup is also up to 25% faster.
- the above allows us to get rid of PDIRUNLOCK.
- also get rid of WANTPARENT (just use LOCKPARENT and unlock it).
- remove an assumption in layer_node_find() that all file systems implement
a recursive VOP_LOCK() (unionfs doesn't).
- require that all file systems supply vfs_vptofh and vfs_fhtovp routines.
fill in eopnotsupp() for file systems that don't support being exported
and remove the checks for NULL. (layerfs calls these without checking.)
- in union_lookup1(), don't change refcounts in the ISDOTDOT case, just
adjust which vnode is locked. fixes PR 33374.
- apply fixes for ufs_rename() from ufs_vnops.c rev. 1.61 to ext2fs_rename().
predictable. This solves a problem that may appear when serving a tmpfs
over NFS: if the server reboots, newly allocated files should have
different file handles; otherwise the remote clients could access files
they were not supposed to touch.
not persistent across reboots but neither are those of MFS, which we are
trying to replace. We should probably warn the user somehow, but not
prevent him doing this if he really wants to.
While here add a "reply" to the code-style change item.
binaries which cast the returned values to 64-bits and fail due to sign
expansion. More details are provided in the big comment in tmpfs.h that
describes how the new tmpfs_dircookie works.
This is a rather ugly hack that shall be fixed with a cleaner solution,
but this resolves the problem in an effective way.
Fixes kern PR/32034.
array's contents and returning all the requested pages. Otherwise there
are problems (accessing invalid memory) when the a_m vector is passed
uninitialized as the NFS server code does. Fixes PR kern/34959.
Note that this is not a "real" fix. While this makes tmpfs's getpages
operation consistent with the behavior of other file systems, it does
not resolve the different semantics between uvn_get and uao_get as
described in PR kern/32166. I'm adding a comment in the code mentioning
exactly this so that it can be reviewed when this last problem is
addressed.
it, not the mtime of the file itself. This fixes the problems exposed when
unpacking software under a tmpfs and trying to build it because dependencies
were not calculated properly (e.g. autoconf 2.60 as reported by tls@).
While touching all vptofh/fhtovp functions, get rid of VFS_MAXFIDSIZ,
version the getfh(2) syscall and explicitly pass the size available in
the filehandle from userland.
Discussed on tech-kern, with lots of help from yamt (thanks!).
- struct timeval time is gone
time.tv_sec -> time_second
- struct timeval mono_time is gone
mono_time.tv_sec -> time_uptime
- access to time via
{get,}{micro,nano,bin}time()
get* versions are fast but less precise
- support NTP nanokernel implementation (NTP API 4)
- further reading:
Timecounter Paper: http://phk.freebsd.dk/pubs/timecounter.pdf
NTP Nanokernel: http://www.eecis.udel.edu/~mills/ntp/html/kern.html
- make sure that kernel only files don't compile in userland using #error
- XXX: some kernel only files still get installed.
- XXX: some files used in userland, don't get installed.
because VOP_UPDATE() usually succeeded, spec_close() was not usually
called. Only skip the spec_close() step if VOP_UPDATE() returns
an error result. Now /dev/watchdog works as expected when /dev/
is a tmpfs; previously, it was impossible to disarm a user-tickled
watchdog.
per yamt's suggestion. Previously, if /dev/ was mounted on a tmpfs,
block device buffers were never flushed to disk. Trying to unmount
a dirty filesystem (umount /dev/wd0e, say) caused an endless stream
of vflushbuf warnings, because tmpfs_bwrite was not flushing buffers.
The fix told to me by yamt solves the problem.
hannken