> ----------------------------
> revision 1.54
> date: 2001/08/26 01:25:12; author: iedowse; state: Exp; lines: +30 -12
> When compacting directories, ufs_direnter() always trusted DIRSIZ()
> to supply the number of bytes to be bcopy()'d to move an entry. If
> d_ino == 0 however, DIRSIZ() is not guaranteed to return a sensible
> length, so ufs_direnter could end up corrupting a directory during
> compaction. In practice I believe this can only happen after fsck_ffs
> has fixed a previously-corrupted directory.
>
> We now deal with any mid-block unused entries specially to avoid
> using DIRSIZ() or bcopy() on such entries. We also ensure that the
> variables 'dsize' and 'spacefree' contain meaningful values at all
> times. Add a few comments to describe better this intricate piece
> of code.
>
> The special handling of mid-block unused entries makes the dirhash-
> specific bugfix in the previous revision (1.53) now uncecessary,
> so this change removes it.
>
> Reviewed by: mckusick
> ----------------------------
> revision 1.53
> date: 2001/08/22 01:35:17; author: iedowse; state: Exp; lines: +2 -2
> When compressing directory blocks, the dirhash code didn't check
> that the directory entry was in use before attempting to find it
> in the hash structures to change its offset. Normally, unused
> entries do not need to be moved, but fsck can leave behind some
> unused entries that do. A dirhash sanity panic resulted when the
> entry to be moved was not found. Add a check that stops entries
> with d_ino == 0 from being passed to ufsdirhash_move().
- for structure fields that are conditionally present,
make those fields always present.
- for functions which are conditionally inline, make them never inline.
- remove some other functions which are conditionally defined but
don't actually do anything anymore.
- make a lock-debugging function conditional on only LOCKDEBUG.
as discussed on tech-kern some time back.
otherwise, once the corresponding bit in the inode bitmap is cleared,
an unrelated inode with the same inode number can be allocated and
ufs_ihashget() picks a stale in-core vnode for it.
PR/32301 by Matthias Scheler.
- rather than embedding bufq_state in driver softc,
have a pointer to the former.
- move bufq related functions from kern/subr_disk.c to kern/subr_bufq.c.
- rename method to strategy for consistency.
- move some definitions which don't need to be exposed to the rest of kernel
from sys/bufq.h to sys/bufq_impl.h.
(is it better to move it to kern/ or somewhere?)
- fix some obvious breakage in dev/qbus/ts.c. (not tested)
- 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.
if the filesystem is not compiled in the kernel still links. Probably
a better solution is to use weak symbols.
- move the filesystem-specific itime macros to the filesystem header files.
from macros to real functions. Original patch and review from chuq.
Note: ext2fs only keeps seconds in the on-disk inode, and msdosfs does not
have enough precision for all fields, so this is not very useful for those
two.
has been written or not individually by (ab)using b_resid
in pcbp as a bitmap.
- add a comment to explain why it's needed.
PR/15364. reviewed by Chuck Silvers.
backing file per attribute type indexed by inode number to hold the extended
attributes.
This is working pretty well on my test systems, except for the "autostart"
feature. I need someone with a better handle on the VFS locking protocol
to go over that.
This is a work-in-progress. There are parts of this that could be re-factored
allowing this approach to be used on other types of file systems.
Adapted from FreeBSD.
to prevent unnecessary block allocations in the case that
page size > block size.
- ufs_balloc_range: use VM_PROT_WRITE+PGO_NOBLOCKALLOC rather than
VM_PROT_READ.
we change the size of the inode, and use ext2fs_size uniformly.
This fixes a crash that occurs when I create a directory, then
move it, all on an ext2 filesystem.
The __UNCONST macro is now used only where necessary and the RW macros
are gone. Most of the changes here are consumers of the
sysctl_createv(9) interface that now takes a pair of const pointers
which used not to be.
- Add a missing ACTIVECG_CLR().
ffs/ffs_snapshot.c:
- Use async/delayed writes for snapshot creation and sync/uncache these buffers
on end. Reduces the time the file system must be suspended.
- Remove um_snaplistsize. Was a duplicate of um_snapblklist[0].
- Byte swap the list of preallocated blocks on read/write instead of access.
- Always keep this list on ip->i_snapblklist so it may be rolled back when the
newest snapshot gets removed. Fixes a rare snapshot corruption when using
more than one snapshot on a file system.
ufs/ufsmount.h:
- Make TAILQ_LAST() possible on member um_snapshots.
- Remove um_snaplistsize. Was a duplicate of um_snapblklist[0].
do this anymore (it hasn't for quite some time). Add a couple of conditional
debugging messages to indicate why segments are not cleaned, in the event
that lfs_segclean is used.
Make the LFCNSEGWAITALL fcntl work again.
segments containing zero-block FINFO records. These records cause segments
to become uncleanable, which would eventually result in a "no clean segments"
panic.
The last block of the file system is written to the snapshot before the
file system is suspended. If the last cylinder group is modified after
the file system is suspended the last block of the snapshot may contain
old data. So update this block again.
lfs_balloc(), and use that to estimate the number of dirty pages belonging
to LFS (subsystem or filesystem). This is almost certainly wrong for
the case of a large mmap()ed region, but the accounting is tighter than
what we had before, and performs much better in the typical case of pages
dirtied through write().
into a single, system-wide table, rather than having a separate hash table
per inode. Significantly reduces the "system" cpu usage of your average
file write.
be assured that the last byte of a file is always allocated. Previously
a file extension could cause the filesystem to be flushed, writing an
inconsistent inode to disk. Although this condition would be corrected
the next time blocks were written to disk, an intervening crash would leave
the filesystem in an inconsistent state, leaving fsck_lfs to complain
of an inode "partially truncated".
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[].
to prevent a deadlock trying to call VOP_PUTPAGES() on a VDIROP vnode.
This can happen when a stacked filesystem is mounted on top of an LFS: an
LFS dirop needs to get a vnode, which is available from the upper layer.
The corresponding lower layer vnode, however, is VDIROP, so the upper layer
can't be cleaned out since its VOP_PUTPAGES() is passed through to the lower
layer, which waits for dirops to drain before it can proceed. Deadlock.
Tweak ufs_makeinode() and ufs_mkdir() to pass the a_vpp argument through
to VOP_VALLOC().
Partially addresses PR # 26043, though it probably does not completely fix
the problem described there.
stuff under '#ifdef DEBUG', and use sysctl knobs to turn on/off particular
parts of the debugging reporting (if DEBUG is enabled). Re-enable the LFS
statistics in sysctl, while I'm there. A bit of a rototill.
Use log(9) to warn the user instead of printf(9). Since the theory is that
the Ifile is "always in cache", but the greater performance risk is
when the inode entries can't be held in cache, note these two cases
separately, at different log levels (notice and warning, respectively).
* Note when lfs_putpages(9) thinks it is not going to be writing any
pages before calling genfs_putpages(9). This prevents a situation in
which blocks can be queued for writing without a segment header.
* Correct computation of NRESERVE(), though it is still a gross
overestimate in most cases. Note that if NRESERVE() is too high, it
may be impossible to create files on the filesystem. We catch this
case on filesystem mount and refuse to mount r/w.
* Allow filesystems to be mounted whose block size is == MAXBSIZE.
* Somewhere along the line, ufs_bmaparray(9) started mangling UNWRITTEN
entries in indirect blocks again, triggering a failed assertion "daddr
<= LFS_MAX_DADDR". Explicitly convert to and from int32_t to correct
this.
* Add a high-water mark for the number of dirty pages any given LFS can
hold before triggering a flush. This is settable by sysctl, but off
(zero) by default.
* Be more careful about the MAX_BYTES and MAX_BUFS computations so we
shouldn't see "please increase to at least zero" messages.
* Note that VBLK and VCHR vnodes can have nonzero values in di_db[0]
even though their v_size == 0. Don't panic when we see this.
* Change lfs_bfree to a signed quantity. The manner in which it is
processed before being passed to the cleaner means that sometimes it
may drop below zero, and the cleaner must be aware of this.
* Never report bfree < 0 (or higher than lfs_dsize) through
lfs_statvfs(9). This prevents df(1) from ever telling us that our full
filesystems have 16TB free.
* Account space allocated through lfs_balloc(9) that does not have
associated buffer headers, so that the pagedaemon doesn't run us out
of segments.
* Return ENOSPC from lfs_balloc(9) when bfree drops to zero.
* Address a deadlock in lfs_bmapv/lfs_markv when the filesystem is being
unmounted. Because vfs_busy() is a shared lock, and
lfs_bmapv/lfs_markv mark the filesystem vfs_busy(), the cleaner can be
holding the lock that umount() is blocking on, then try to vfs_busy()
again in getnewvnode().
Will allow INSTALL_TINY to fit back in its designated space.
Since the calling code doesn't allow a snapshot mount to fail, this code
will output a warning and delete any snapshots it finds.
This only happend on rw mounts - snapshots don't seem to be created
when mounting ro.
The whole way the snapshots gets mounted is a PITA anyway, the superblock
'last mounted' time should be used to validate that the fs hasn't been
mounted elsewhere.
Like Linux, automagically convert old filesystem to use this,
if they are already at revision 1.
For revision 0, just punt (unlike Linux; makes me a bit too nervous.)
There should be an option to fsck_ext2fs to upgrade revision 0 to revision 1.
Reviewd by Manuel (bouyer@).
- Ffs internal snapshots get compiled in unconditionally.
- File system snapshot device fss(4) added to all kernel configs that
have a disk. Device is commented out on all non-GENERIC kernels.
Reviewed by: Jason Thorpe <thorpej@netbsd.org>
directories are created on the fly and used to increase
performance by circumventing ufs_lookup's linear search.
Dirhash is enabled by the UFS_DIRHASH option, but not
by default.
this means we can no longer look at the vnode size to determine how many
pages to request in a fault, which is good since for NFS the size can change
out from under us on the server anyway. there's also a new flag UBC_UNMAP
for ubc_release(), so that the file system code can make the decision about
whether to cache mappings for files being used as executables.
foo_mountfs() to foo_mount(), to match the new mountroot API.
Also, for ext2fs and lfs, copy some restructuring from ffs to allow changing
file system parameters without specifying the device name.
(ntfs could use some more work.)
and just passes it on to the file system functions. This avoids opening and
closing the device several times.
Mentioned on tech-kern some time ago, IIRC. I've been running this for a
long time.
top bit in block addresses.
Also, change some daddr_t->int32_t casts (mostly as arguments to ufs_rw32(),
where they would get promoted anyway) to u_int32_t.
previously, the number was relative to the cylinder group, which was confusing.
prefix debug message with "ifree:" so this can be differentiated in bug reports.
this condition can occur if ufs_inactive experiences failure attempting
to write the inode out. Instead, have ufs_reclaim always call VOP_UPDATE
which will only write out the inode if there are unflushed changes
calls to ensure that the vnode lock state is as expected when the VOP
call is made. Modify vnode_if.src to set the expected state according
to the documenting lock table for each VOP. Modify vnode_if.sh to emit
the checks.
Notes:
- The checks are only performed if the vnode has the VLOCKSWORK bit
set. Some file systems (e.g. specfs) don't even bother with vnode
locks, so of course the checks will fail.
- We can't actually run with VNODE_LOCKDEBUG because there are so many
vnode locking problems, not the least of which is the "use SHARED for
VOP_READ()" issue, which screws things up for the entire call chain.
Inspired by similar changes in OpenBSD, but implemented differently.
yamt