where segment 0 is being considered for writing. This allows for automated
checkpoint vailidity scanning, and could be used (in conjunction with the
existing LFCNREWIND) for e.g. snapshot dumps as well.
Include a regression test that does such scanning.
When writing the Ifile, loop through the dirty block list three times to
make sure that the checkpoint is always consistent (the first and second
times the Ifile blocks can cross a segment boundary; not so the third time
unless the segments are very small). Discovered by using the aforementioned
regression test.
explicitly (especially since we didn't know about VFREEING at all before),
but notice the EBUSY return from vget() instead.
Fix some more MP locking protocol issues, most of which were pointed out by
Christian Ehrhardt this morning on tech-kern.
instead of bytes for the index, and never search below fs->lfs_freehd.
Fix a bug in the previous version of the search (an erroneous assumption
that ino_t was signed).
Free the bitmap when we unmount the filesystem.
The writer daemon, if it does not need to flush the whole filesystem,
now only writes the vnodes for which the pagedaemon has requested pageouts
(although it does not pay attention to the page ranges the pagedaemon
supplies).
by Michel Oey, in which an aged LFS writes up to an extra Ifile block for
every file created; and paves the way for the truncation of the Ifile when
many files are deleted.
* Correct (weak) segment lock assertions in lfs_fragextend and lfs_putpages.
* Keep IN_MODIFIED set if we run out of avail in lfs_putpages.
* Don't try to (re)write buffers on a VBLK vnode; fixes a panic I found
while running with an LFS root.
* Raise priority of LFCNSEGWAIT to PVFS; PUSER is way too low for
something the pagedaemon is relying on.
- remove GOP_SIZE_READ/GOP_SIZE_WRITE flags.
they have not been used since the change.
- ufs_balloc_range: remove code which has been no-op since the change.
thanks Konrad Schroder for explaining the original intention of the code.
- ffs_gop_size: don't extend past eof, in the case of GOP_SIZE_MEM.
otherwise genfs_getpages end up to allocate pages past eof unnecessarily.
* Acknowledge that sometimes there are more dirty pages to be written to
disk than clean segments. When we reach the danger line,
lfs_gop_write() now returns EAGAIN. The caller of VOP_PUTPAGES(), if
it holds the segment lock, drops it and waits for the cleaner to make
room before continuing.
* Note and avoid a three-way deadlock in lfs_putpages (a writer holding
a page busy blocks on the cleaner while the cleaner blocks on the
segment lock while lfs_putpages blocks on the page).
- 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.
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.
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.
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().
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.
* Rather than using mnt_maxsymlinklen to indicate that a file systems returns
d_type fields(!), add a new internal flag, IMNT_DTYPE.
Add 3 new elements to ufsmount:
* um_maxsymlinklen, replaces mnt_maxsymlinklen (which never should have existed
in the first place).
* um_dirblksiz, which tracks the current directory block size, eliminating the
FS-specific checks littered throughout the code. This may be used later to
make the block size variable.
* um_maxfilesize, which is the maximum file size, possibly adjusted lower due
to implementation issues.
Sync some bug fixes from FFS into ext2fs, particularly:
* ffs_lookup.c 1.21, 1.28, 1.33, 1.48
* ffs_inode.c 1.43, 1.44, 1.45, 1.66, 1.67
* ffs_vnops.c 1.84, 1.85, 1.86
Clean up some crappy pointer frobnication.
rarely in the normal case. (Note: This happens at reboot/shutdown time because
all file systems are unmounted.)
Also, for IN_MODIFY, use IN_ACCESSED, not IN_MODIFIED; otherwise "ls -l" of
your device node or FIFO would cause the time stamps to get written too
quickly.
setting those flags, it does not cause the inode to be written in the periodic
sync. This is used for writes to special files (devices and named pipes) and
FIFOs.
Do not preemptively sync updates to access times and modification times. They
are now updated in the inode only opportunistically, or when the file or device
is closed. (Really, it should be delayed beyond close, but this is enough to
help substantially with device nodes.)
And the most amusing part:
Trickle sync was broken on both FFS and ext2fs, in different ways. In FFS, the
periodic call to VFS_SYNC(MNT_LAZY) was still causing all file data to be
synced. In ext2fs, it was causing the metadata to *not* be synced. We now
only call VOP_UPDATE() on the node if we're doing MNT_LAZY. I've confirmed
that we do in fact trickle correctly now.
- 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>
and tweak lkminit_*.c (where applicable) to call them, and to call
sysctl_teardown() when being unloaded.
This consists of (1) making setup functions not be static when being
compiled as lkms (change to sys/sysctl.h), (2) making prototypes
visible for the various setup functions in header files (changes to
various header files), and (3) making simple "load" and "unload"
functions in the actual lkminit stuff.
linux_sysctl.c also needs its root exposed (ie, made not static) for
this (when built as an lkm).
an _LKM.
This adds pools to the list of things that lkms must do manually
because they're set up with link sets. Not that there's anything
wrong with link sets, but that we need to try harder to remember that
lkms are second class citizens. Of a sort.
to pool_init. Untouched pools are ones that either in arch-specific
code, or aren't initialiased during initial system startup.
Convert struct session, ucred and lockf to pools.
VOP_STRATEGY(bp) is replaced by one of two new functions:
- VOP_STRATEGY(vp, bp) Call the strategy routine of vp for bp.
- DEV_STRATEGY(bp) Call the d_strategy routine of bp->b_dev for bp.
DEV_STRATEGY(bp) is used only for block-to-block device situations.
virtual memory reservation and a private pool of memory pages -- by a scheme
based on memory pools.
This allows better utilization of memory because buffers can now be allocated
with a granularity finer than the system's native page size (useful for
filesystems with e.g. 1k or 2k fragment sizes). It also avoids fragmentation
of virtual to physical memory mappings (due to the former fixed virtual
address reservation) resulting in better utilization of MMU resources on some
platforms. Finally, the scheme is more flexible by allowing run-time decisions
on the amount of memory to be used for buffers.
On the other hand, the effectiveness of the LRU queue for buffer recycling
may be somewhat reduced compared to the traditional method since, due to the
nature of the pool based memory allocation, the actual least recently used
buffer may release its memory to a pool different from the one needed by a
newly allocated buffer. However, this effect will kick in only if the
system is under memory pressure.
Gone are the old kern_sysctl(), cpu_sysctl(), hw_sysctl(),
vfs_sysctl(), etc, routines, along with sysctl_int() et al. Now all
nodes are registered with the tree, and nodes can be added (or
removed) easily, and I/O to and from the tree is handled generically.
Since the nodes are registered with the tree, the mapping from name to
number (and back again) can now be discovered, instead of having to be
hard coded. Adding new nodes to the tree is likewise much simpler --
the new infrastructure handles almost all the work for simple types,
and just about anything else can be done with a small helper function.
All existing nodes are where they were before (numerically speaking),
so all existing consumers of sysctl information should notice no
difference.
PS - I'm sorry, but there's a distinct lack of documentation at the
moment. I'm working on sysctl(3/8/9) right now, and I promise to
watch out for buses.
mv MNT_GONE, MNT_UNMOUNT and MNT_WANTRDWR to this field
additonally add mnt_writeopcountupper and mnt_writeopcountlower fields
in preparation for pending write suspension support work
bump kernel version to 1.6ZD