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).
fixes the case where a directory lookup is done in a directory has never
been visted/listed; the search optimalisation that searches the directory
from where it left behind the last time would never reach the initial
offset of zero since it would always have at least processed one entry.
of rolling around VOP_FSYNC(). The user server will be given the
VFS_SYNC instruction and it can do its own equivalent of VOP_FSYNC()
if it pleases, no need for the kernel to explicitly issue #{vnodes}
FSYNCs.
kernel caching. Currently supported are only flushing the name
cache for a directory or flushing the name cache for the entire fs.
Also, get rid of PNODE_INACTIVE status, since it was racy and
essentially didn't work. All this on top of being useless in the
first place ....
kernel->server calls at that time and it allows a window where
operations use an incorrect root node cookie.
XXX: there's still a (very much smaller and biglock safe) race, but
that's going to be solved by some more thorough restructuring
from under someone waiting for the fs server response in puffs_unmount()
if the descriptor was closed during the response wait (such as bug
leading to a crash in fs implementation unmount()).
- 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().
from under us while waiting for syncer_lock and before we got to vfs_busy.
This happens easily e.g. when the userspace server loses its will to
live in VOP_RECLAIM, which is called from vflush() in VFS_UNMOUNT. We
get two competing unmounters. When the first one finishes, it releases
syncer_lock. Now the second one tries to vfs_busy(), but is greeted
with garbage in *mp.
XXX: Technically this is a more general issue and should be fixed
elsewhere, but it's hard to trigger it with normal file systems
unless they are unmounted "simultaneously" twice and are dirty
enough for flushing to take a while. So make a note about it in
the little black book next to the poems and postpone the crusade
for now.
mmap and therefore execution of binaries starting to work, some
speed improvements with large file I/O also. caching semantics
and error case handling most likely need revisiting.
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.
reference to the parent directory's vnode instead of its smbnode to
avoid a use-after-free bug causing a panic when a smbfs mount is
forcefully unmounted.
Keep trying to flush the vnode list for the mount while some are still
busy and we are making progress towards making them not busy. This
stops attempts to unmount idle smbfs mounts failing with EBUSY.
The easiest way to reproduce the above problem, from what I have seen is:
1) Assume /s is a smbfs mount point.
2) mount /s
3) stat /s/foo/1
4) umount /s
Returns error because the file system is busy.
5) Shutdown the machine: panic in smbfs_reclaim because vrele
accesses already-released memory.
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@).
loops where vnodes can get removed or added during the loops. This could
lead to panic's on unmount since nodes are skipped or otherwise
TAILQ_NEXT(0xdeadbeef, ...) was dereferenced.
all waiters *before* trying to get the syncer lock necessary for
dounmount(). This prevents a deadlock if the userspace server dies
while the syncer is running.
getnewvnode() while holding on to any vnode lock deadlocks the
system if the file system is being forcibly unmounted.
Normal file systems don't trigger this problem because of two reaons:
1) they don't hold on to vnode locks while idling who-knows-where, so
the race doesn't trigger
2) they aren't usually unmounted with FORCE; puffs is, in case "someone"
manages to make a crashy userspace server
Nevertheless, a real solution is slowly being braised.
It contains the VFS attachment and userspace message-passing interface.
This work was initially started and completed for Google SoC 2005
and tweaked to work a bit better in the past few weeks. While
being far from complete, it is functional enough to be able and
stable to host a fairly general-purpose in-memory file system in
userspace. Even so, puffs should be considered experimental and
no binary compatibility for interfaces or crash-freedom or zero
security implications should be relied upon just yet.
The GSoC project was mentored by William Studenmund and the final
review for the code was done by Christos.
vnodes were synced and processed backwards. This meant that the last
accessed node was processed first and the earlierst last.
An extra benefit is the removal of the ugly hack from the Berkly days on
LFS.
In the proces, i've also replaced the various variations hand written loops
by the TAILQ_FOREACH() macro's.
the udf_verbose variable. So when something goes wrong, it can be examined
on the spot without needing to reboot a new kernel and possibly loosing
state.
. get rid of struct adirent which didn't match struct dirent anymore
. fix cookies, move all the code handling them to the end of the function
Includes many minor changes to the code of this function.
"Add a 3rd entry in the cache, which keeps the end position
from just before extending a file.
This has the desired effect of keeping the write speed constant."
And yes, that helps a lot copying large files... always at full speed
now. This closes my PR kern/30868 "Poor performance copying large files
on msdosfs".
Also remove a 2 if-statements testing the same condition, combine them.
All that from Rhialto, thank you very much.
If you perform this request on a directory with exactly 50 files
(plus '.' and '..' which brings the total to 52 objects), the first
reply for the SMB server completely satisfies the query (server
side is Windows 2000 Professional).
The smbfs client then performs a TRANS2_FIND_NEXT2 using the last
file name as the resume key. The response returns a SearchCount
of zero (ctx->f_ecnt == 0) and an EndOfSearch code of zero.
Any attempt to get more entries with calls to TRANS2_FIND_NEXT2
result in Badfid (bad file descriptor). I suspect the return of
SearchCount of zero means that end-of-search has been reached and
the Sid is now closed.
The solution is to set "SMB_RDD_EOF | SMB_RDD_NOCLOSE" after getting
back a zero SearchCount, I've tested this in the field on a quite
a few systems, aggressively accessing Windows shares over smbfs
and it appears flawless.
I was initially concerned about the possibility of resource exhaustion
on the Windows server. I was afraid by not officially closing the
search, it would leave a resource hung-up and over time, exhaust
some sort of "open search table" limit. I've since convinced myself
this is NOT the case.
Windows needs to be able to handle clients that come and go over
time. If the search is not closed, Windows will close it if it
finds it needs more resources. I've testing this on directory
searches descending into 10's of thousands of folders, with 100's
of thousands of files.
it was initialised quite late due to its reliance on disc data the mount
process could have stopped before initialising and thus could panic again
only now for uninitialising an not initialised pool! *sigh*
the same memory block allocated as before and it bombs out on its
descriptor pool allready being initialised. It turns out that the pool was
not allways destroyed. This fix ought to clean it up whatever the cause of
the mishap that results in a reject.
253 of the superblock be zero. Searching the net failed to find any
justification for checking these bytes; all available references say
that they are part of the boot code and not BOOTSIG2 and BOOTSIG3.
Modify the MSDOS 7.1 bootsector definition to have 420 bytes of boot
code and no BOOTSIG[23], rather than 418 bytes of boot code, to follow
available references and apparent Windows practice. A test build
showed that these defines are not used other than in the check removed
by this commit.
Patch tested on netbsd-3, and enabled mounting of a 4 GB CF formatted
under Windows XP and then in a digital camera. The CF was previously
unmountable.
Concept approved on tech-kern by christos@ and martin@.
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!).
allocated space was 2048 bytes, but when adding 1024 to the variable
`unix_name' to split the allocated space in half it effectively starts just
OUTSIDE the allocated space. This ought to fix memory corruption bugs when
using UDF.
This is a routine to revisit one day.
- 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
- use vmspace rather than proc or lwp where appropriate.
the latter is more natural to specify an address space.
(and less likely to be abused for random purposes.)
- fix a swdmover race.
hannken