Make VFS hooks dynamic while we're here and say farewell to VFS_ATTACH and
VFS_HOOKS_ATTACH linksets.
As a consequence, most of the file systems can now be loaded as new style
modules.
Quick sanity check by ad@.
Introduce a per-FS rename lock and new vfsops to manipulate it.
Get this lock while renaming. Also add another relookup() in do_sys_rename,
which is a hack to kludge around some of the worst deficiencies of
ufs_rename.
reviewed-by: pooka (and an earlier rev by ad)
posted on tech-kern with no objections.
The general trend is to remove it from all kernel interfaces and
this is a start. In case the calling lwp is desired, curlwp should
be used.
quick consensus on tech-kern
knew what it was supposed to be used for and wrstuden gave a go-ahead
* while rototilling, convert file systems which went easily to
use VFS_PROTOS() instead of manually prototyping the methods
fs code is a kernel buffer, pass though the length of the buffer as well.
Since the length of the userspace buffer isn'it (yet) passed through the mount
system call, add a field to the vfsops structure containing the default length.
Split sys_mount() for calls from compat code.
Ride one of the recent kernel version changes - old fs LKMs will load, but
sys_mount() will reject any attempt to use them.
MNT_FORCE is given
* decrease cargo cult index by getting rid of commented sections
with mntflushbuf() in them - AFAICT the call was removed from our
kernel over 13 years ago with the 4.4BSDlite import
corresponding flags.
Revert softdep_trackbufs() to its state before vn_start_write() was added.
Remove from struct mount now unneeded flags IMNT_SUSPEND* and
members mnt_writeopcountupper, mnt_writeopcountlower and mnt_leaf.
Welcome to 4.99.17
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().
- Add a few scopes to the kernel: system, network, and machdep.
- Add a few more actions/sub-actions (requests), and start using them as
opposed to the KAUTH_GENERIC_ISSUSER place-holders.
- Introduce a basic set of listeners that implement our "traditional"
security model, called "bsd44". This is the default (and only) model we
have at the moment.
- Update all relevant documentation.
- Add some code and docs to help folks who want to actually use this stuff:
* There's a sample overlay model, sitting on-top of "bsd44", for
fast experimenting with tweaking just a subset of an existing model.
This is pretty cool because it's *really* straightforward to do stuff
you had to use ugly hacks for until now...
* And of course, documentation describing how to do the above for quick
reference, including code samples.
All of these changes were tested for regressions using a Python-based
testsuite that will be (I hope) available soon via pkgsrc. Information
about the tests, and how to write new ones, can be found on:
http://kauth.linbsd.org/kauthwiki
NOTE FOR DEVELOPERS: *PLEASE* don't add any code that does any of the
following:
- Uses a KAUTH_GENERIC_ISSUSER kauth(9) request,
- Checks 'securelevel' directly,
- Checks a uid/gid directly.
(or if you feel you have to, contact me first)
This is still work in progress; It's far from being done, but now it'll
be a lot easier.
Relevant mailing list threads:
http://mail-index.netbsd.org/tech-security/2006/01/25/0011.htmlhttp://mail-index.netbsd.org/tech-security/2006/03/24/0001.htmlhttp://mail-index.netbsd.org/tech-security/2006/04/18/0000.htmlhttp://mail-index.netbsd.org/tech-security/2006/05/15/0000.htmlhttp://mail-index.netbsd.org/tech-security/2006/08/01/0000.htmlhttp://mail-index.netbsd.org/tech-security/2006/08/25/0000.html
Many thanks to YAMAMOTO Takashi, Matt Thomas, and Christos Zoulas for help
stablizing kauth(9).
Full credit for the regression tests, making sure these changes didn't break
anything, goes to Matt Fleming and Jaime Fournier.
Happy birthday Randi! :)
- Remove all NFS related stuff from file system specific code.
- Drop the vfs_checkexp hook and generalize it in the new nfs_check_export
function, thus removing redundancy from all file systems.
- Move all NFS export-related stuff from kern/vfs_subr.c to the new
file sys/nfs/nfs_export.c. The former was becoming large and its code
is always compiled, regardless of the build options. Using the latter,
the code is only compiled in when NFSSERVER is enabled. While doing this,
also make some functions in nfs_subs.c conditional to NFSSERVER.
- Add a new command in nfssvc(2), called NFSSVC_SETEXPORTSLIST, that takes a
path and a set of export entries. At the moment it can only clear the
exports list or append entries, one by one, but it is done in a way that
allows setting the whole set of entries atomically in the future (see the
comment in mountd_set_exports_list or in doc/TODO).
- Change mountd(8) to use the nfssvc(2) system call instead of mount(2) so
that it becomes file system agnostic. In fact, all this whole thing was
done to remove a 'XXX' block from this utility!
- Change the mount*, newfs and fsck* userland utilities to not deal with NFS
exports initialization; done internally by the kernel when initializing
the NFS support for each file system.
- Implement an interface for VFS (called VFS hooks) so that several kernel
subsystems can run arbitrary code upon receipt of specific VFS events.
At the moment, this only provides support for unmount and is used to
destroy NFS exports lists from the file systems being unmounted, though it
has room for extension.
Thanks go to yamt@, chs@, thorpej@, wrstuden@ and others for their comments
and advice in the development of this patch.
into the "vfsops" link set.
- Use VFS_ATTACH() where vfsops are declared for individual file systems.
- In vfsinit(), traverse the "vfsops" link set, rather than vfs_list_initial[].
PDIRUNLOCK. The whole reason we have the flag is to note (rare)
cases where we are supposed to have the parent directory locked
but don't. Permits error handling code to know what to do with
the parrent vnode (vrele() vs vput()).
through a layered file system.
Note: we don't actually support snapshots through a layered file system,
and this routine returns an error. However we: 1) have clearly documented
what needs fixing (which isn't trivial to fix) and 2) if we do fix
this, all layered file systems can take advantage of it at once.
fix for layered-file-removal. It will work for the case of accessing
and deleting a file through the layered file system. Accessing via
the layer and deleting on the underlying still won't work, nor will
accessing via complicated structures (like two umap layers over a
given file systems).
We still need VOP_UPCALL(), but this is better than things were before.
This patch has been discussed off & on for a while. This incarnation
was tested by hannken at netbsd dot org.
- Not enabled by default. Needs kernel option FFS_SNAPSHOT.
- Change parameters of ffs_blkfree.
- Let the copy-on-write functions return an error so spec_strategy
may fail if the copy-on-write fails.
- Change genfs_*lock*() to use vp->v_vnlock instead of &vp->v_lock.
- Add flag B_METAONLY to VOP_BALLOC to return indirect block buffer.
- Add a function ffs_checkfreefile needed for snapshot creation.
- Add special handling of snapshot files:
Snapshots may not be opened for writing and the attributes are read-only.
Use the mtime as the time this snapshot was taken.
Deny mtime updates for snapshot files.
- Add function transferlockers to transfer any waiting processes from
one lock to another.
- Add vfsop VFS_SNAPSHOT to take a snapshot and make it accessible through
a vnode.
- Add snapshot support to ls, fsck_ffs and dump.
Welcome to 2.0F.
Approved by: Jason R. Thorpe <thorpej@netbsd.org>
rumble