on ia64) was not the result of a change in the vector operations. It
was caused by the NFS locking code using a FIFO and those bypassing
the vnode. This indirectly caused the panic. The NFS locking code has
been changed.
Requested by: phk
prematurely report that they were full and/or to panic the kernel
with the message ``ffs_clusteralloc: allocated out of group''.
Submitted by: Henry Whincup <henry@jot.to>
MFC after: 1 week
split the conversion of the remaining three filesystems out from the root
mounting changes, so in one go:
cd9660:
Convert to nmount.
Add omount compat shims.
Remove dedicated rootfs mounting code.
Use vfs_mountedfrom()
Rely on vfs_mount.c calling VFS_STATFS()
nfs(client):
Convert to nmount (the simple way, mount_nfs(8) is still necessary).
Add omount compat shims.
Drop COMPAT_PRELITE2 mount arg compatibility.
ffs:
Convert to nmount.
Add omount compat shims.
Remove dedicated rootfs mounting code.
Use vfs_mountedfrom()
Rely on vfs_mount.c calling VFS_STATFS()
Remove vfs_omount() method, all filesystems are now converted.
Remove MNTK_WANTRDWR, handling RO/RW conversions is a filesystem
task, and they all do it now.
Change rootmounting to use DEVFS trampoline:
vfs_mount.c:
Mount devfs on /. Devfs needs no 'from' so this is clean.
symlink /dev to /. This makes it possible to lookup /dev/foo.
Mount "real" root filesystem on /.
Surgically move the devfs mountpoint from under the real root
filesystem onto /dev in the real root filesystem.
Remove now unnecessary getdiskbyname().
kern_init.c:
Don't do devfs mounting and rootvnode assignment here, it was
already handled by vfs_mount.c.
Remove now unused bdevvp(), addaliasu() and addalias(). Put the
few necessary lines in devfs where they belong. This eliminates the
second-last source of bogo vnodes, leaving only the lemming-syncer.
Remove rootdev variable, it doesn't give meaning in a global context and
was not trustworth anyway. Correct information is provided by
statfs(/).
doesn't. Most of the implementations have grown weeds for this so they
copy some fields from mnt_stat if the passed argument isn't that.
Fix this the cleaner way: Always call the implementation on mnt_stat
and copy that in toto to the VFS_STATFS argument if different.
commit. In the new world order, the transitive closure on the vector
operations is not precomputed. As such, it's unsafe to actually use
any of the function pointers in an indirect function call. They can
be null, and we need to use the default vector in that case.
This is mostly a quick fix for the four function pointers that are
ed explicitly. A more generic or scalable solution is likely to see
the light of day.
No pathos on: current@
initializations but we did have lofty goals and big ideals.
Adjust to more contemporary circumstances and gain type checking.
Replace the entire vop_t frobbing thing with properly typed
structures. The only casualty is that we can not add a new
VOP_ method with a loadable module. History has not given
us reason to belive this would ever be feasible in the the
first place.
Eliminate in toto VOCALL(), vop_t, VNODEOP_SET() etc.
Give coda correct prototypes and function definitions for
all vop_()s.
Generate a bit more data from the vnode_if.src file: a
struct vop_vector and protype typedefs for all vop methods.
Add a new vop_bypass() and make vop_default be a pointer
to another struct vop_vector.
Remove a lot of vfs_init since vop_vector is ready to use
from the compiler.
Cast various vop_mumble() to void * with uppercase name,
for instance VOP_PANIC, VOP_NULL etc.
Implement VCALL() by making vdesc_offset the offsetof() the
relevant function pointer in vop_vector. This is disgusting
but since the code is generated by a script comparatively
safe. The alternative for nullfs etc. would be much worse.
Fix up all vnode method vectors to remove casts so they
become typesafe. (The bulk of this is generated by scripts)
setting the B_REMFREE flag in the buf. This is done to prevent lock order
reversals with code that must call bremfree() with a local lock held.
This also reduces overhead by removing two lock operations per buf for
fsync() and similar.
- Check for the B_REMFREE flag in brelse() and bqrelse() after the bqlock
has been acquired so that we may remove ourself from the free-list.
- Provide a bremfreef() function to immediately remove a buf from a
free-list for use only by NFS. This is done because the nfsclient code
overloads the b_freelist queue for its own async. io queue.
- Simplify the numfreebuffers accounting by removing a switch statement
that executed the same code in every possible case.
- getnewbuf() can encounter locked bufs on free-lists once Giant is removed.
Remove a panic associated with this condition and delay asserts that
inspect the buf until after it is locked.
Reviewed by: phk
Sponsored by: Isilon Systems, Inc.
instead of a vnode for it.
The vnode_pager does not and should not have any interest in what
the filesystem uses for backend.
(vfs_cluster doesn't use the backing store argument.)
This eliminates a bunch of vnode overhead (approx 1-2 % speed
improvement) and gives us more control over the access to the storage
device.
Access counts on the underlying device are not correctly tracked and
therefore it is possible to read-only mount the same disk device multiple
times:
syv# mount -p
/dev/md0 /var ufs rw 2 2
/dev/ad0 /mnt ufs ro 1 1
/dev/ad0 /mnt2 ufs ro 1 1
/dev/ad0 /mnt3 ufs ro 1 1
Since UFS/FFS is not a synchrousely consistent filesystem (ie: it caches
things in RAM) this is not possible with read-write mounts, and the system
will correctly reject this.
Details:
Add a geom consumer and a bufobj pointer to ufsmount.
Eliminate the vnode argument from softdep_disk_prewrite().
Pick the vnode out of bp->b_vp for now. Eventually we
should find it through bp->b_bufobj->b_private.
In the mountcode, use g_vfs_open() once we have used
VOP_ACCESS() to check permissions.
When upgrading and downgrading between r/o and r/w do the
right thing with GEOM access counts. Remove all the
workarounds for not being able to do this with VOP_OPEN().
If we are the root mount, drop the exclusive access count
until we upgrade to r/w. This allows fsck of the root
filesystem and the MNT_RELOAD to work correctly.
Set bo_private to the GEOM consumer on the device bufobj.
Change the ffs_ops->strategy function to call g_vfs_strategy()
In ufs_strategy() directly call the strategy on the disk
bufobj. Same in rawread.
In ffs_fsync() we will no longer see VCHR device nodes, so
remove code which synced the filesystem mounted on it, in
case we came there. I'm not sure this code made sense in
the first place since we would have taken the specfs route
on such a vnode.
Redo the highly bogus readblock() function in the snapshot
code to something slightly less bogus: Constructing an uio
and using physio was really quite a detour. Instead just
fill in a bio and ship it down.
Give ffs it's own bufobj->bo_ops vector and create a private strategy
routine, (currently misnamed for forwards compatibility), which is
just a copy of the generic bufstrategy routine except we call
softdep_disk_prewrite() directly instead of through the buf_prewrite()
indirection.
Teach UFS about the need for softdep_disk_prewrite() and call the
function directly in FFS.
Remove buf_prewrite() from the default bufstrategy() and from the
global bio_ops method vector.
We keep si_bsize_phys around for now as that is the simplest way to pull
the number out of disk device drivers in devfs_open(). The correct solution
would be to do an ioctl(DIOCGSECTORSIZE), but the point is probably mooth
when filesystems sit on GEOM, so don't bother for now.
is ffs_copyonwrite() and the only place it can be called from is FFS which
would never want to call another filesystems copyonwrite method, should one
exist, so there is no reason why anything generic should know about this.
Extend it with a strategy method.
Add bufstrategy() which do the usual VOP_SPECSTRATEGY/VOP_STRATEGY
song and dance.
Rename ibwrite to bufwrite().
Move the two NFS buf_ops to more sensible places, add bufstrategy
to them.
Add inlines for bwrite() and bstrategy() which calls through
buf->b_bufobj->b_ops->b_{write,strategy}().
Replace almost all VOP_STRATEGY()/VOP_SPECSTRATEGY() calls with bstrategy().
Initialize b_bufobj for all buffers.
Make incore() and gbincore() take a bufobj instead of a vnode.
Make inmem() local to vfs_bio.c
Change a lot of VI_[UN]LOCK(bp->b_vp) to BO_[UN]LOCK(bp->b_bufobj)
also VI_MTX() to BO_MTX(),
Make buf_vlist_add() take a bufobj instead of a vnode.
Eliminate other uses of bp->b_vp where bp->b_bufobj will do.
Various minor polishing: remove "register", turn panic into KASSERT,
use new function declarations, TAILQ_FOREACH_SAFE() etc.
Add bufobj_wref(), bufobj_wdrop() and bufobj_wwait() to handle the write
count on a bufobj. Bufobj_wdrop() replaces vwakeup().
Use these functions all relevant places except in ffs_softdep.c where
the use if interlocked_sleep() makes this impossible.
Rename b_vnbufs to b_bobufs now that we touch all the relevant files anyway.
It can be used to delay mounting root partition to give a chance to GEOM
providers to show up.
Now, when there is no needed provider, vfs_rootmount() function will look
for it every second and if it can't be find in defined time, it'll ask
for root device name (before this change it was done immediately).
This will allow to boot from gmirror device in degraded mode.
too much kernel copying, but it is not the right way to do it, and it is
in the way for straightening out the buffer cache.
The right way is to pass the VM page array down through the struct
bio to the disk device driver and DMA directly in to/out off the
physical memory. Once the VM/buf thing is sorted out it is next on
the list.
Retire most of vnode method. ffs_getpages(). It is not clear if what is
left shouldn't be in the default implementation which we now fall back to.
Retire specfs_getpages() as well, as it has no users now.
and the previously malloc'ed snapshot lock.
Malloc struct snapdata instead of just the lock.
Replace snapshot fields in cdev with pointer to snapdata (saves 16 bytes).
While here, give the private readblock() function a vnode argument
in preparation for moving UFS to access GEOM directly.
preparation for integration of p4::phk_bufwork. In the future,
local filesystems will talk to GEOM directly and they will consequently
be able to issue BIO_DELETE directly. Since the removal of the fla
driver, BIO_DELETE has effectively been a no-op anyway.
field.
Replace three instances of longhaired initialization va_filerev fields.
Added XXX comment wondering why we don't use random bits instead of
uptime of the system for this purpose.
be manipulated by prison root. In 4.x prison root can not manipulate
system flags, regardless of the security level. This behavior
should remain consistent to avoid any surprises which could lead
to security problems for system administrators which give out
privileged access to jails.
This commit changes suser_cred's flag argument from SUSER_ALLOWJAIL
to 0. This will prevent prison root from being able to manipulate
system flags on files.
This may be a MFC candidate for RELENG_5.
Discussed with: cperciva
Reviewed by: rwatson
Approved by: bmilekic (mentor)
PR: kern/70298
has only been partly initialized via newfs(8) so that it applies to both
UFS1 and UFS2.
Submitted by: "Xin LI" delphij at frontfree dot net
MFC: maybe?
address of the dirhash, rather than the first sizeof(struct dirhash
*) bytes of the structure (which, thankfully, seem to be constant).
Submitted by: Ted Unangst <tedu@zeitbombe.org>
MFC after: 2 weeks
a more complete subsystem, and removes the knowlege of how things are
implemented from the drivers. Include locking around filter ops, so a
module like aio will know when not to be unloaded if there are outstanding
knotes using it's filter ops.
Currently, it uses the MTX_DUPOK even though it is not always safe to
aquire duplicate locks. Witness currently doesn't support the ability
to discover if a dup lock is ok (in some cases).
Reviewed by: green, rwatson (both earlier versions)
and refuse initializing filesystems with a wrong version. This will
aid maintenance activites on the 5-stable branch.
s/vfs_mount/vfs_omount/
s/vfs_nmount/vfs_mount/
Name our filesystems mount function consistently.
Eliminate the namiedata argument to both vfs_mount and vfs_omount.
It was originally there to save stack space. A few places abused
it to get hold of some credentials to pass around. Effectively
it is unused.
Reorganize the root filesystem selection code.
Add local rootvp variables as needed.
Remove checks for miniroot's in the swappartition. We never did that
and most of the filesystems could never be used for that, but it had
still been copy&pasted all over the place.
somewhat clearer, but more importantly allows for a consistent naming
scheme for suser_cred flags.
The old name is still defined, but will be removed in a few days (unless I
hear any complaints...)
Discussed with: rwatson, scottl
Requested by: jhb
This is to allow filesystems to decide based on the passed thread
which vnode to return.
Several filesystems used curthread, they now use the passed thread.
our cached 'next vnode' being removed from this mountpoint. If we
find that it was recycled, we restart our traversal from the start
of the list.
Code to do that is in all local disk filesystems (and a few other
places) and looks roughly like this:
MNT_ILOCK(mp);
loop:
for (vp = TAILQ_FIRST(&mp...);
(vp = nvp) != NULL;
nvp = TAILQ_NEXT(vp,...)) {
if (vp->v_mount != mp)
goto loop;
MNT_IUNLOCK(mp);
...
MNT_ILOCK(mp);
}
MNT_IUNLOCK(mp);
The code which takes vnodes off a mountpoint looks like this:
MNT_ILOCK(vp->v_mount);
...
TAILQ_REMOVE(&vp->v_mount->mnt_nvnodelist, vp, v_nmntvnodes);
...
MNT_IUNLOCK(vp->v_mount);
...
vp->v_mount = something;
(Take a moment and try to spot the locking error before you read on.)
On a SMP system, one CPU could have removed nvp from our mountlist
but not yet gotten to assign a new value to vp->v_mount while another
CPU simultaneously get to the top of the traversal loop where it
finds that (vp->v_mount != mp) is not true despite the fact that
the vnode has indeed been removed from our mountpoint.
Fix:
Introduce the macro MNT_VNODE_FOREACH() to traverse the list of
vnodes on a mountpoint while taking into account that vnodes may
be removed from the list as we go. This saves approx 65 lines of
duplicated code.
Split the insmntque() which potentially moves a vnode from one mount
point to another into delmntque() and insmntque() which does just
what the names say.
Fix delmntque() to set vp->v_mount to NULL while holding the
mountpoint lock.
because UFS uses fixed-size directory blocks. When using this code with
other file systems, such as HFS+, the value of auio.uio_resid will need
to be taken into account.
local to a function. Remove a couple of blank lines in variable
declarations.
In one case, explicitly test against NULL rather than using a pointer
as a boolean directly.
lots of errors. Blind substitution of "dev_t foo" by "struct cdev *foo"
in comments usually just created an English syntax error (e.g.,
"struct cdev *changes"), but here it did less than that since the dev_t
is a user dev_t.
fixes was applicable to HEAD, originally it was thought this
should only be done in RELENG_4. Implement IO_INVAL in the vnode
op for writing by marking the buffer as "no cache". This fix
has already been applied to RELENG_4 as Rev. 1.65.2.15 of
ufs/ufs/ufs_readwrite.c.
Reviewed by: alc, tegge
fragment to zero the valid parts of a VM_IO buffer.
RE would like this to be part of 4.10-RC3 so this will be MFC-ed immediately.
Reviewed by: alc, tegge
things which compare /etc/fstab entries to results from
getfsstat(). The real way to fix this is to make 'ufs2'
a recognized filesystem (for real, no beating around the
bush).
This should fix things like 'umount -a -t ufs' now.
Appologies for the previous breakage.
libufs, which only works for Charlie root.
This change reverts the introduction of libufs and moves the
check into the kernel. Since the f_fstypename is the same
for both ufs and ufs2, we check fs_magic for presence of
ufs2 and copy "ufs2" explicitly instead.
Submitted by: Christian S.J. Peron <maneo@bsdpro.com>
license, per letter dated July 22, 1999 and irc message from Robert
Watson saying that clause 3 can be removed from those files with an
NAI copyright that also have only a University of California
copyrights.
Approved by: core, rwatson
WARNS=6. I don't change the WARNS level in the Makefile because I
didn't tested this on other archs.
The fs.h fix was suggested by: marcel
Reviewed by: md5(1)
group block locked. If filesystem has any active snapshots, bawrite
can come back trying to allocate new snapshot data block from the same
cylinder group and cause panic due to recursive lock attempt.
PR: 64206
Reviewed by: mckusick
Tested by: pjd
were a rather overwhelming task. I soon learned that if you don't know
where you're going to store something, at least try to pile it next to
something slightly related in the hope that a pattern emerges.
Apply the same principle to the ffs/snapshot/softupdates code which have
leaked into specfs: Add yet a buf-quasi-method and call it from the
only two places I can see it can make a difference and implement the
magic in ffs_softdep.c where it belongs.
It's not pretty, but at least it's one less layer violated.
AFTER the call to vn_start_write(), not before it. Otherwise, it is
possible to unlock it multiple times if the vn_start_write() fails.
Submitted by: Juergen Hannken-Illjes <hannken@eis.cs.tu-bs.de>
In ufs_lock, check for attempts to acquire shared locks on
snapshot files and change them to be exclusive locks. This
change eliminates deadlocks and machine lockups reported in
-current since most read requests started using shared lock
requests.
Submitted by: Jun Kuriyama <kuriyama@imgsrc.co.jp>
to use the "year1-year3" format, as opposed to "year1, year2, year3".
This seems to make lawyers more happy, but also prevents the
lines from getting excessively long as the years start to add up.
Suggested by: imp
- don't unlock the vnode after vinvalbuf() only to have to relock it
almost immediately.
- don't refer to devices classified by vn_isdisk() as block devices.
operators) in and near revs.1.169-1.170 (open mode bandaid). This
(or better a proper fix) should have been done before cloning the
bandaid to many other file systems.
- rev.1.42 of ffs_readwrite.c added a special case in ffs_read() for reads
that are initially at EOF, and rev.1.62 of ufs_readwrite.c fixed
timestamp bugs in it. Removal of most of vfs_ioopt made it just and
optimization, and removal of the vm object reference calls made it less
than an optimization. It was cloned in rev.1.94 of ufs_readwrite.c as
part of cloning ffs_extwrite() although it was always less than an
optimization in ffs_extwrite().
- some comments, compound statements and vertical whitespace were vestiges
of dead code.
- struct plimit includes a mutex to protect a reference count. The plimit
structure is treated similarly to struct ucred in that is is always copy
on write, so having a reference to a structure is sufficient to read from
it without needing a further lock.
- The proc lock protects the p_limit pointer and must be held while reading
limits from a process to keep the limit structure from changing out from
under you while reading from it.
- Various global limits that are ints are not protected by a lock since
int writes are atomic on all the archs we support and thus a lock
wouldn't buy us anything.
- All accesses to individual resource limits from a process are abstracted
behind a simple lim_rlimit(), lim_max(), and lim_cur() API that return
either an rlimit, or the current or max individual limit of the specified
resource from a process.
- dosetrlimit() was renamed to kern_setrlimit() to match existing style of
other similar syscall helper functions.
- The alpha OSF/1 compat layer no longer calls getrlimit() and setrlimit()
(it didn't used the stackgap when it should have) but uses lim_rlimit()
and kern_setrlimit() instead.
- The svr4 compat no longer uses the stackgap for resource limits calls,
but uses lim_rlimit() and kern_setrlimit() instead.
- The ibcs2 compat no longer uses the stackgap for resource limits. It
also no longer uses the stackgap for accessing sysctl's for the
ibcs2_sysconf() syscall but uses kernel_sysctl() instead. As a result,
ibcs2_sysconf() no longer needs Giant.
- The p_rlimit macro no longer exists.
Submitted by: mtm (mostly, I only did a few cleanups and catchups)
Tested on: i386
Compiled on: alpha, amd64
and ffs_write(). These calls trace their origins to the dead vfs_ioopt
code, first appearing in revision 1.39 of ufs_readwrite.c.
Observed by: bde
Discussed with: tegge
Replace wrong check returned EFBIG with EOVERFLOW handling from POSIX:
36708 [EOVERFLOW] The file is a regular file, nbyte is greater than 0, the
starting position is before the end-of-file, and the starting position is
greater than or equal to the offset maximum established in the open file
description associated with fildes.
ffs_write:
Replace u_int64_t cast with uoff_t cast which is more natural for types
used.
ffs_write & ffs_read:
Remove uio_offset and uio_resid checks for negative values, the caller
supposed to do it already. Add comments about it.
Reviewed by: bde
Move diagnostic printf after vget. This might delay the debug
output some, but at least it keeps kernel from exploding if
DEBUG_VFS_LOCKS is in effect.
system super block after fsck has repaired the file system. The value of
fs_ronly was getting overwritten, which caused ffs_update() to attempt to
update inode timestamps even though the file system was still mounted
read-only.
This fixes the "giving up on N buffers" error that is triggered by running
fsck on the root file system and then rebooting without mounting the file
system read-write.
of newfs, to signify the newfs operation has not yet completed. Re-
write the superblock with the correct magic number once all of the
cylinder groups have been created to show the operation has finished.
Sponsored by: St. Bernard Software
accurate reporting of multi-terabyte filesystem sizes.
You should build and boot a new kernel BEFORE doing a `make world'
as the new kernel will know about binaries using the old statfs
structure, but an old kernel will not know about the new system
calls that support the new statfs structure. Running an old kernel
after a `make world' will cause programs such as `df' that do a
statfs system call to fail with a bad system call.
Reviewed by: Bruce Evans <bde@zeta.org.au>
Reviewed by: Tim Robbins <tjr@freebsd.org>
Reviewed by: Julian Elischer <julian@elischer.org>
Reviewed by: the hoards of <arch@freebsd.org>
Sponsored by: DARPA & NAI Labs.
Introduce two new macros MNT_ILOCK(mp)/MNT_IUNLOCK(mp) to
operate on this mutex transparently.
Eventually new mutex will be protecting more fields in
struct mount, not only vnode list.
Discussed with: jeff
wasn't curthread, i.e. when we receive a thread pointer to use
as a function argument. Use VOP_UNLOCK/vrele in these cases.
The only case there td != curthread known at the moment is
boot() calling sync with thread0 pointer.
This fixes the panic on shutdown people have reported.
those cylinder groups that have at least 75% of the average free
space per cylinder group for that file system are considered as
candidates for the creation of a new directory. The previous formula
for minbfree would set it to zero if the file system was more than
75% full, which allowed cylinder groups with no free space at all
to be chosen as candidates for directory creation, which resulted
in an expensive search for free blocks for each file that was
subsequently created in that directory.
Modify the calculation of minifree in the same way.
Decrease maxcontigdirs as the file system fills to decrease the
likelyhood that a cluster of directories will overflow the available
space in a cylinder group.
Reviewed by: mckusick
Tested by: kmarx@vicor.com
MFC after: 2 weeks
so make the code slightly more uniform. The vnode lock is acquired in
all cases and now the only difference between VCHR and other is we
call UFS_UPDATE instead of VOP_FSYNC().
- Slightly rewrite the fsync loop to be more lock friendly. We must
acquire the vnode interlock before dropping the mnt lock. We must
also check XLOCK to prevent vclean() races.
- Use LK_INTERLOCK in the vget() in ffs_sync to further prevent vclean()
races.
- Use a local variable to store the results of the nvp == TAILQ_NEXT
test so that we do not access the vp after we've vrele()d it.
- Add an XXX comment about UFS_UPDATE() not being protected by any lock
here. I suspect that it should need the VOP lock.
we release the mntvnode_mtx.
- Call vgonel() directly instead of going through vrecycle() since we own
the interlock now.
- Remove a few cases where we locked the interlock just so that we could
call VOP_UNLOCK with interlock held.
mntvnode_mtx.
- Use a local variable to store the results of the test to see if the
next vnode on the mount list has changed. This is so that we no longer
acess the vnode after we vput() it.
in a list head instead of a pointer to the first element at the time of
the first call. These lists are subject to change, and getdirtybuf()
would refetch from the wrong list in some cases.
Spottedy by: tegge
Pointy hat to: me
bail out if the buffer is not already present.
- The buffer returned by incore() is not locked and should not be sent to
brelse(). Use getblk() with the new GB_NOCREAT flag to preserve the
desired semantics.
caller to acquire it. This permits drain_output() to be done atomically
with other operations as well as reducing the number of lock operations.
- Assert that the proper locks are held in drain_output().
- Change getdirtybuf() to accept a mutex as an argument. This mutex is used
to protect the vnode's buf list and the BKGRDWAIT flag. This lock is
dropped when we successfully acquire a buffer and held on return
otherwise. These semantics reduce the number of cumbersome cases in
calling code.
- Pass the mtx from getdirtybuf() into interlocked_sleep() and allow this
mutex to be used as the interlock argument to BUF_LOCK() in the LOCKBUF
case of interlocked_sleep().
- Change the return value of getdirtybuf() to be the resulting locked buffer
or NULL otherwise. This is for callers who pass in a list head that
requires a lock. It is necessary since the lock that protects the list
head must be dropped in getdirtybuf() so that we don't have a lock order
reversal with the buf queues lock in bremfree().
- Adjust all callers of getdirtybuf() to match the new semantics.
- Add a comment in indir_trunc() that points at unlocked access to a buf.
This may also be one of the last instances of incore() in the tree.
- Surround all accesses of the BKGRD{WAIT,INPROG} flags with the vnode
interlock.
- Don't use the B_LOCKED flag and QUEUE_LOCKED for background write
buffers. Check for the BKGRDINPROG flag before recycling or throwing
away a buffer. We do this instead because it is not safe for us to move
the original buffer to a new queue from the callback on the background
write buffer.
- Remove the B_LOCKED flag and the locked buffer queue. They are no longer
used.
- The vnode interlock is used around checks for BKGRDINPROG where it may
not be strictly necessary. If we hold the buf lock the a back-ground
write will not be started without our knowledge, one may only be
completed while we're not looking. Rather than remove the code, Document
two of the places where this extra locking is done. A pass should be
done to verify and minimize the locking later.
get the same value from ip->i_ump->um_devvp.
This saves a pointer in the memory copies of inodes, which can
easily run into several hundred kilobytes.
The extra indirection is unmeasurable in benchmarks.
Approved by: mckusick
generate the inode mode from a default ACL and creation mask,
implement ufs_sync_inode_from_acl() using acl_posix1e_newfilemode().
Since ACL_OVERRIDE_MASK/ACL_PRESERVE_MASK are defined, we no
longer need to explicitly pass in a "preserve_mask" field: this
is implicit in the use of POSIX.1e semantics.
Note: this change contains a semantic bugfix for new file creation:
we now intersect the ACL-generated mode and the cmode requested by
the user process. This means permissions on newly created file
objects will now be more conservative. In the future, we may want
to provide alternative semantics (similar to Solaris and Linux) in
which the ACL mask overrides the umask, permitting ACLs to broaden
the rights beyond the requested umask.
PR: 50148
Reported by: Ritz, Bruno <bruno_ritz@gmx.ch>
Obtained from: TrustedBSD Project
cases:
- Setting sticky bit on non-directory
- Setting setgid on a file with a group that isn't in the effective
or extended groups of the authorizing credential
I.e., test the requirement first, then do the privilege test,
rather than doing the privilege test regardless of the need for
privilege.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
kernel ACL interfaces and system call names.
Break out UFS2 and FFS extattr delete and list vnode operations from
setextattr and getextattr to deleteextattr and listextattr, which
cleans up the implementations, and makes the results more readable,
and makes the APIs more clear.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
contain the filedescriptor number on opens from userland.
The index is used rather than a "struct file *" since it conveys a bit
more information, which may be useful to in particular fdescfs and /dev/fd/*
For now pass -1 all over the place.
UFS quota implementation. Push some quite broken access control
logic out of ufs_quotactl() into the individual command
implementations in ufs_quota.c; fix that logic. Pass in the thread
argument to any quotactl command that will need to perform access
control.
o quotaon() requires privilege (PRISON_ROOT).
o quotaoff() requires privilege (PRISON_ROOT).
o getquota() requires that:
If the type is USRQUOTA, either the effective uid match the
requested quota ID, that the unprivileged_get_quota flag be
set, or that the thread be privileged (PRISON_ROOT).
If the type is GRPQUOTA, require that either the thread be
a member of the group represented by the requested quota ID,
that the unprivileged_get_quota flag be set, or that the
thread be privileged (PRISON_ROOT).
o setquota() requires privilege (PRISON_ROOT).
o setuse() requires privilege (PRISON_ROOT).
o qsync() requires no special privilege (consistent with what
was present before, but probably not very useful).
Add a new sysctl, security.bsd.unprivileged_get_quota, which when
set to a non-zero value, will permit unprivileged users to query user
quotas with non-matching uids and gids. Set this to 0 by default
to be mostly consistent with the previous behavior (the same for
USRQUOTA, but not for GRPQUOTA).
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
attribute name of "" from ffs_getextattr(). Invoking VOP_GETETATTR()
with an empty name is now no longer supported; user application
compatibility is provided by a system call level compatibility
wrapper. We make sure to explicitly reject attempts to set an EA
with the name "".
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
extended attribute retrieval code: it's no longer special-cased,
and is caught by the normal UFS1 EA validity checks (and, in
fact, returns the same error, EINVAL).
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
if we permit them to occur, the kernel panics due to our performing
EA operations using VOP_STRATEGY on the vnode. This went unnoticed
previously because there are very for users of device nodes on UFS2
due to the introduction of devfs. However, this can come up with
the Linux compat directories and its hard-coded dev nodes (which will
need to go away as we move away from hard-coded device numbers).
This can come up if you use EA-intensive features such as ACLs and
MAC.
The proper fix is pretty complicated, but this band-aid would be
an excellent MFC candidate for the release.
only while holding appropriate vnode locks. This patch slides the lock
release for ufs_extattr_enable() to continue to hold the active vnode lock
on a backing file until after the flag change; it also acquires a vnode
lock when disabling an attribute and hence clearing a flag on the backing
vnode. This permits VFS_DEBUG_LOCKS to run UFS1 extended attributes
without panicking, as well as preventing a potential race and vnode flag
problem.
Approved by: re (jhb)
Pointed out by: DEBUG_VFS_LOCKS
These fields can be left as NULL if ffs_vget() allocates an inode but
fails before the dinode memory has been allocated. There are two cases
when this can occur: when we lose a race and another process has added
the inode to the hash, and when reading the inode off disk fails.
The bug was observed by Kris on one of the package-building machines.
See http://marc.theaimsgroup.com/?l=freebsd-current&m=105172731013411&w=2
In Kris's case, it was the bread() that failed because of a disk error.
The alternative to this patch is to ensure that ffs_vget() does not call
vput() when the inode that hasn't been properly initialised.
kg_nice is now protected by both. Being protected by both means that
other places in the kernel that want to read kg_nice only need one of the
two locks.
requiring locked bufs in vfs_bio_awrite(). Previously the buf could
have been written out by fsync before we acquired the buf lock if it
weren't for giant. The cluster_wbuild() handles this race properly but
the single write at the end of vfs_bio_awrite() would not.
- Modify flushbufqueues() so there is only one copy of the loop. Pass a
parameter in that says whether or not we should sync bufs with deps.
- Call flushbufqueues() a second time and then break if we couldn't find
any bufs without deps.
of a snapshot's copy of a superblock. This patch fixes a panic
when taking a snapshot of a 4096/512 filesystem.
Reported by: Ian Freislich <ianf@za.uu.net>
Sponsored by: DARPA & NAI Labs.
- Define one flag GB_LOCK_NOWAIT that tells getblk() to pass the LK_NOWAIT
flag to the initial BUF_LOCK(). This will eventually be used in cases
were we want to use a buffer only if it is not currently in use.
- Convert all consumers of the getblk() api to use this extra parameter.
Reviwed by: arch
Not objected to by: mckusick
Remove extraneous uses of vop_null, instead defering to the default op.
Rename vnode type "vfs" to the more descriptive "syncer".
Fix formatting for various filesystems that use vop_print.
from the filesystem size field to the filesystem maximum blocksize
field. The problem is that older versions of growfs updated only the
new size field and not the old size field. This resulted in the old
(smaller) size field being copied up to the new size field which
caused the filesystem to appear to fsck to be badly trashed.
This also adds a sanity check to ensure that the superblock is not
being updated when the filesystem is mounted read-only. Obviously
such an update should never happen.
Reported by: Nate Lawson <nate@root.org>
Sponsored by: DARPA & NAI Labs.
- Remove the buftimelock mutex and acquire the buf's interlock to protect
these fields instead.
- Hold the vnode interlock while locking bufs on the clean/dirty queues.
This reduces some cases from one BUF_LOCK with a LK_NOWAIT and another
BUF_LOCK with a LK_TIMEFAIL to a single lock.
Reviewed by: arch, mckusick
a snapshot. As part of taking a snapshot of a filesystem, the kernel
builds up a list of the filesystem metadata (such as the cylinder
group bitmaps) that are contained in the snapshot. When doing a
copy-on-write check, the list is first consulted. If the block being
written is found on the list, then the full snapshot lookup can be
avoided. Besides providing an important performance speedup this
check also avoids a potential deadlock between the code creating
the snapshot and the bufdaemon trying to cleanup snapshot related
buffers. This fix creates a temporary list containing the key
metadata blocks that can cause the deadlock. This temporary list
is used between the time that the snapshot is first enabled and the
time that the fully complete list is built.
Reported by: Attila Nagy <bra@fsn.hu>
Sponsored by: DARPA & NAI Labs.
is being taken from panicing with either "freeing free block" or
"freeing free inode". The problem arises when the snapshot code
is scanning the filesystem looking for inodes with a reference
count of zero (e.g., unlinked but still open) so that it can
expunge them from its view. If it encounters a reclaimed vnode
and has to restart its scan, then it will panic if it encounters
and tries to free an inode that it has already processed. The fix
is to check each candidate inode to see if it has already been
processed before trying to delete it from the snapshot image.
Sponsored by: DARPA & NAI Labs.
that they convert to 64-bit values before shifting rather than
afterwards. Once fixed, they can be used rather than inline expanded.
Sponsored by: DARPA & NAI Labs.
values for the initial inode generation numbers in newfs and for
newly allocated inode generation numbers in the kernel.
Submitted by: Theo de Raadt <deraadt@cvs.openbsd.org>
Sponsored by: DARPA & NAI Labs.
that is protected by the vnode lock.
- Move B_SCANNED into b_vflags and call it BV_SCANNED.
- Create a vop_stdfsync() modeled after spec's sync.
- Replace spec_fsync, msdos_fsync, and hpfs_fsync with the stdfsync and some
fs specific processing. This gives all of these filesystems proper
behavior wrt MNT_WAIT/NOWAIT and the use of the B_SCANNED flag.
- Annotate the locking in buf.h
pointer types, and remove a huge number of casts from code using it.
Change struct xfile xf_data to xun_data (ABI is still compatible).
If we need to add a #define for f_data and xf_data we can, but I don't
think it will be necessary. There are no operational changes in this
commit.
padding is not specific to non-i386 architectures. It is
caused by non-i386 specific alignment requirements of
fs_swuid,
o Add a CTASSERT to catch a change in the size of struct fs
at compile-time rather than run-time.
Ok'd: gordon
Tested on: i386 ia64
will be used to support volume names with the help of a GEOM module (to be
committed). uuid will be used to deal with conflicting volume names (which
doesn't work just yet).
Approved by: mckusick@
repeatedly truncate the same file. Each time the file is truncated,
a buffer is grabbed to store the indirect block numbers that need
to be freed. Those blocks cannot be freed until the inode claiming
them is written to disk. Thus, the number of buffers being held by
soft updates explodes and in extreme cases can run the kernel out
of buffers. The problem can be avoided by doing an fsync on the
file every debug.maxindirdep truncates (currently defaulted to 50).
The fsync causes the inode to be written so that the held buffers
can be freed. The check for excessive buffers is checked as part
of the existing hook for excessive dependencies (softdep_slowdown)
in the truncate code.
Reported by: David Schultz <dschultz@uclink.Berkeley.EDU>
Sponsored by: DARPA & NAI Labs.
MFC after: 3 weeks
to sort out disk-io from file-io in the vm/buffer/filesystem space.
The intent is to sort VOP_STRATEGY calls into those which operate
on "real" vnodes and those which operate on VCHR vnodes. For
the latter kind, the call will be changed to VOP_SPECSTRATEGY,
possibly conditionally for those places where dual-use happens.
Add a default VOP_SPECSTRATEGY method which will call the normal
VOP_STRATEGY. First time it is called it will print debugging
information. This will only happen if a normal vnode is passed
to VOP_SPECSTRATEGY by mistake.
Add a real VOP_SPECSTRATEGY in specfs, which does what VOP_STRATEGY
does on a VCHR vnode today.
Add a new VOP_STRATEGY method in specfs to catch instances where
the conversion to VOP_SPECSTRATEGY has not yet happened. Handle
the request just like we always did, but first time called print
debugging information.
Apart up to two instances of console messages per boot, this amounts
to a glorified no-op commit.
If you get any of the messages on your console I would very much
like a copy of them mailed to phk@freebsd.org
kern/vfs_defaults.c it is wrong for the individual filesystems to use
the std* functions as that prevents override of the default.
Found by: src/tools/tools/vop_table
this was causing filedesc work to be very painful.
In order to make this work split out sigio definitions to thier own header
(sigio.h) which is included from proc.h for the time being.
Remove the malloctype from the ufs mount structure, instead add a callback
to the storage method for freeing inodes: UFS_IFREE().
Add vfs_ifree() method function which frees an inode.
Unvariablelize the malloc type used for allocating inodes.
so as to work correctly on 64-bit platforms.
Reported-by: Jake Burkholder <jake@locore.ca>
Sponsored by: DARPA & NAI Labs.
Approved by: Ian Dowse <iedowse@maths.tcd.ie>
that were copied in all of the earlier snapshots, thus its precomputed
list must be used in the copyonwrite test. Using incomplete lists may
lead to deadlock. Also do not include the blocks used for the indirect
pointers in the indirect pointers as this may lead to inconsistent
snapshots.
Sponsored by: DARPA & NAI Labs.
Approved by: re
previously allocated block as the previous use of the block may
have fallen out of the cache. Failure to reread its contents cause
zeroed results to be written instead of the proper contents.
Conversely, when the block is going to be entirely filled in, it
is not necessary reread the old contents.
Sponsored by: DARPA & NAI Labs.
Approved by: re
converting from individual vnode locks to the snapshot
lock, be sure to pass any waiting processes along to the
new lock as well. This transfer is done by a new function
in the lock manager, transferlockers(from_lock, to_lock);
Thanks to Lamont Granquist <lamont@scriptkiddie.org> for
his help in pounding on snapshots beyond all reason and
finding this deadlock.
Sponsored by: DARPA & NAI Labs.
1) Release the snapshot file lock while suspending the system. Otherwise
a process trying to read the lock may block on its containing directory
preventing the suspension from completing. Thanks to Sean Kelly
<smkelly@zombie.org> for finding this deadlock.
2) Replace some bdwrite's with bawrite's so as not to fill all the
buffers with dirty data. The buffers could not be cleaned as the
snapshot vnode was locked hence the system could deadlock when
making snapshots of really massive filesystems. Thanks to
Hidetoshi Shimokawa <simokawa@sat.t.u-tokyo.ac.jp> for figuring
this out.
Sponsored by: DARPA & NAI Labs.
before using it to write the superblock. This is to guard against
accidentally trashing the disklabel if the superblock format missed
being upgraded by the new kernel.
Reported by: Sam Leffler <sam@errno.com>
Sponsored by: DARPA & NAI Labs.
Approved by: Murray Stokely <murray@FreeBSD.org>
the old 8-bit fs_old_flags to the new location the first time that the
filesystem is mounted by a new kernel. One of the unused flags in
fs_old_flags is used to indicate that the flags have been moved.
Leave the fs_old_flags word intact so that it will work properly if
used on an old kernel.
Change the fs_sblockloc superblock location field to be in units
of bytes instead of in units of filesystem fragments. The old units
did not work properly when the fragment size exceeeded the superblock
size (8192). Update old fs_sblockloc values at the same time that
the flags are moved.
Suggested by: BOUWSMA Barry <freebsd-misuser@netscum.dyndns.dk>
Sponsored by: DARPA & NAI Labs.
in half because of reports that under heavy load the kernel could
exhaust its memory pool. The limit is now (desiredvnodes * 4)
rather than (desiredvnodes * 8), so it will still scale with
larger systems, just not as quickly.
Sponsored by: DARPA & NAI Labs.
not have hit the disk and the dependencies cannot be unrolled.
In this case, the system will mark the buffer as dirty again so
that the write can be retried in the future. When the write
succeeds or the system gives up on the buffer and marks it as
invalid (B_INVAL), the dependencies will be cleared.
Sponsored by: DARPA & NAI Labs.
"refreshing" the label on the vnode before use, just get the label
right from inception. For single-label file systems, set the label
in the generic VFS getnewvnode() code; for multi-label file systems,
leave the labeling up to the file system. With UFS1/2, this means
reading the extended attribute during vfs_vget() as the inode is
pulled off disk, rather than hitting the extended attributes
frequently during operations later, improving performance. This
also corrects sematics for shared vnode locks, which were not
previously present in the system. This chances the cache
coherrency properties WRT out-of-band access to label data, but in
an acceptable form. With UFS1, there is a small race condition
during automatic extended attribute start -- this is not present
with UFS2, and occurs because EAs aren't available at vnode
inception. We'll introduce a work around for this shortly.
Approved by: re
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
check for and/or report I/O errors. The result is that a VFS_SYNC
or VOP_FSYNC called with MNT_WAIT could loop infinitely on ufs in
the presence of a hard error writing a disk sector or in a filesystem
full condition. This patch ensures that I/O errors will always be
checked and returned. This patch also ensures that every call to
VFS_SYNC or VOP_FSYNC with MNT_WAIT set checks for and takes
appropriate action when an error is returned.
Sponsored by: DARPA & NAI Labs.
the ffs_copyonwrite routine to avoid a deadlock between the syncer
daemon trying to sync out a snapshot vnode and the bufdaemon
trying to write out a buffer containing the snapshot inode.
With any luck this will be the last snapshot race condition.
Sponsored by: DARPA & NAI Labs.
a full filesystem. Previously, if the allocation failed, we had to
fsync the file before rolling back any partial allocation of indirect
blocks. Most block allocation requests only need to allocate a single
data block and if that allocation fails, there is nothing to unroll.
So, before doing the fsync, we check to see if any rollback will
really be necessary. If none is necessary, then we simply return.
This update eliminates the flurry of disk activity that got triggered
whenever a filesystem would run out of space.
Sponsored by: DARPA & NAI Labs.
that works in the new threaded kernel. It was commented out of
the disksort routine earlier this year for the reasons given in
kern/subr_disklabel.c (which is where this code used to reside
before it moved to kern/subr_disk.c):
----------------------------
revision 1.65
date: 2002/04/22 06:53:20; author: phk; state: Exp; lines: +5 -0
Comment out Kirks io-request priority hack until we can do this in a
civilized way which doesn't cause grief.
The problem is that it is not generally safe to cast a "struct bio
*" to a "struct buf *". Things like ccd, vinum, ata-raid and GEOM
constructs bio's which are not entrails of a struct buf.
Also, curthread may or may not have anything to do with the I/O request
at hand.
The correct solution can either be to tag struct bio's with a
priority derived from the requesting threads nice and have disksort
act on this field, this wouldn't address the "silly-seek syndrome"
where two equal processes bang the diskheads from one edge to the
other of the disk repeatedly.
Alternatively, and probably better: a sleep should be introduced
either at the time the I/O is requested or at the time it is completed
where we can be sure to sleep in the right thread.
The sleep also needs to be in constant timeunits, 1/hz can be practicaly
any sub-second size, at high HZ the current code practically doesn't
do anything.
----------------------------
As suggested in this comment, it is no longer located in the disk sort
routine, but rather now resides in spec_strategy where the disk operations
are being queued by the thread that is associated with the process that
is really requesting the I/O. At that point, the disk queues are not
visible, so the I/O for positively niced processes is always slowed
down whether or not there is other activity on the disk.
On the issue of scaling HZ, I believe that the current scheme is
better than using a fixed quantum of time. As machines and I/O
subsystems get faster, the resolution on the clock also rises.
So, ten years from now we will be slowing things down for shorter
periods of time, but the proportional effect on the system will
be about the same as it is today. So, I view this as a feature
rather than a drawback. Hence this patch sticks with using HZ.
Sponsored by: DARPA & NAI Labs.
Reviewed by: Poul-Henning Kamp <phk@critter.freebsd.dk>
_POSIX_MAC_PRESENT based on available mount flags, if the services are
available.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
of a file in chunks that are less then the filesystem block size, if the
data is not already cached the system will perform a read-before-write.
The problem is that it does this on a block-by-block basis, breaking up the
I/Os and making clustering impossible for the writes. Programs such
as INN using cyclic file buffers suffer greatly. This problem is only going
to get worse as we use larger and larger filesystem block sizes.
The solution is to extend the sequential heuristic so UFS[2] can perform
a far larger read and readahead when dealing with this case.
(note: maximum disk write bandwidth is 27MB/sec thru filesystem)
(note: filesystem blocksize in test is 8K (1K frag))
dd if=/dev/zero of=test.dat bs=1k count=2m conv=notrunc
Before: (note half of these are reads)
tty da0 da1 acd0 cpu
tin tout KB/t tps MB/s KB/t tps MB/s KB/t tps MB/s us ni sy in id
0 76 14.21 598 8.30 0.00 0 0.00 0.00 0 0.00 0 0 7 1 92
0 76 14.09 813 11.19 0.00 0 0.00 0.00 0 0.00 0 0 9 5 86
0 76 14.28 821 11.45 0.00 0 0.00 0.00 0 0.00 0 0 8 1 91
After: (note half of these are reads)
tty da0 da1 acd0 cpu
tin tout KB/t tps MB/s KB/t tps MB/s KB/t tps MB/s us ni sy in id
0 76 63.62 434 26.99 0.00 0 0.00 0.00 0 0.00 0 0 18 1 80
0 76 63.58 424 26.30 0.00 0 0.00 0.00 0 0.00 0 0 17 2 82
0 76 63.82 438 27.32 0.00 0 0.00 0.00 0 0.00 1 0 19 2 79
Reviewed by: mckusick
Approved by: re
X-MFC after: immediately (was heavily tested in -stable for 4 months)
is required to use EAs with UFS2, and that UFS2 is recommend for EA use
for a variety of reasons.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
note that UFS2 doesn't require explicit extended attribute configuration,
and is recommends for this and other reasons if you plan to use ACLs.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
a common lock. This change avoids a deadlock between snapshots when
separate requests cause them to deadlock checking each other for a
need to copy blocks that are close enough together that they fall
into the same indirect block. Although I had anticipated a slowdown
from contention for the single lock, my filesystem benchmarks show
no measurable change in throughput on a uniprocessor system with
three active snapshots. I conjecture that this result is because
every copy-on-write fault must check all the active snapshots, so
the process was inherently serial already. This change removes the
last of the deadlocks of which I am aware in snapshots.
Sponsored by: DARPA & NAI Labs.
to be administratively disabled as needed on UFS/UFS2 file systems. This
also has the effect of preventing the slightly more expensive ACL code
from running on non-ACL file systems, avoiding storage allocation for
ACLs that may be read from disk. MNT_ACLS may be set at mount-time
using mount -o acls, or implicitly by setting the FS_ACLS flag using
tunefs. On UFS1, you may also have to configure ACL store.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
automatically set MNT_MULTILABEL in the mount flags.
If FS_ACLS is set in a UFS or UFS2 superblock, automatically
set MNT_ACLS in the mount flags.
If either of these flags is set, but the appropriate kernel option
to support the features associated with the flag isn't available,
then print a warning at mount-time.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
or fifo in UFS2, the normal ufs_strategy routine needs to be used
rather than the spec_strategy or fifo_strategy routine. Thus the
ffsext_strategy routine is interposed in the ffs_vnops vectors for
special devices and fifo's to pick off this special case. Otherwise
it simply falls through to the usual spec_strategy or fifo_strategy
routine.
Submitted by: Robert Watson <rwatson@FreeBSD.org>
Sponsored by: DARPA & NAI Labs.
if failures occur, make sure that we release both the default ACL
and access ACL storage during new object creation.
Spotted by: phk and his pet flexelint
Sponsored by: DARPA, Network Associates Laboratories
FS_ACLS Administrative enable/disable of extended ACL support
FS_MULTILABEL Administrative flag to indicate to the MAC Framework
that objects in the file system are individually
labeled using extended attributes.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
Reviewed by: (in principal) mckusick, phk
that use it. Specifically, vop_stdlock uses the lock pointed to by
vp->v_vnlock. By default, getnewvnode sets up vp->v_vnlock to
reference vp->v_lock. Filesystems that wish to use the default
do not need to allocate a lock at the front of their node structure
(as some still did) or do a lockinit. They can simply start using
vn_lock/VOP_UNLOCK. Filesystems that wish to manage their own locks,
but still use the vop_stdlock functions (such as nullfs) can simply
replace vp->v_vnlock with a pointer to the lock that they wish to
have used for the vnode. Such filesystems are responsible for
setting the vp->v_vnlock back to the default in their vop_reclaim
routine (e.g., vp->v_vnlock = &vp->v_lock).
In theory, this set of changes cleans up the existing filesystem
lock interface and should have no function change to the existing
locking scheme.
Sponsored by: DARPA & NAI Labs.
Whenever doing a copy-on-write check, first look in the list of
initially allocated blocks to see if it is there. If so, no further
check is needed. If not, fall through and do the full check. This
change eliminates one of two known deadlocks caused by snapshots.
Handling the second deadlock will be the subject of another check-in.
This change also reduces the cost of the copy-on-write check by
speeding up the verification of frequently checked blocks.
Sponsored by: DARPA & NAI Labs.
Whenever doing a copy-on-write check, first look in the list of
initially allocated blocks to see if it is there. If so, no further
check is needed. If not, fall through and do the full check. This
change eliminates one of two known deadlocks caused by snapshots.
Handling the second deadlock will be the subject of another check-in.
This change also reduces the cost of the copy-on-write check by
speeding up the verification of frequently checked blocks.
Sponsored by: DARPA & NAI Labs.
even when the underlying device has a larger sector size. Therefore,
the filesystem code should not (and with this patch does not) try to
use the underlying sector size when doing disk block address calculations.
This patch fixes problems in -current when using the swap-based
memory-disk device (mdconfig -a -t swap ...). This bugfix is not
relevant to -stable as -stable does not have the memory-disk device.
Sponsored by: DARPA & NAI Labs.
wasn't doing. Rather than just lock and unlock the vnode around the call
to VOP_FSYNC(), implement rwatson's suggestion to lock the file vnode
in kern_link() before calling VOP_LINK(), since the other filesystems
also locked the file vnode right away in their link methods. Remove the
locking and and unlocking from the leaf filesystem link methods.
Reviewed by: rwatson, bde (except for the unionfs_link() changes)
v_tag is now const char * and should only be used for debugging.
Additionally:
1. All users of VT_NTS now check vfsconf->vf_type VFCF_NETWORK
2. The user of VT_PROCFS now checks for the new flag VV_PROCDEP, which
is propagated by pseudofs to all child vnodes if the fs sets PFS_PROCDEP.
Suggested by: phk
Reviewed by: bde, rwatson (earlier version)
Changed rename(2) to follow the letter of the POSIX spec. POSIX
requires rename() to have no effect if its args "resolve to the same
existing file". I think "file" can only reasonably be read as referring
to the inode, although the rationale and "resolve" seem to say that
sameness is at the level of (resolved) directory entries.
ext2fs_vnops.c, ufs_vnops.c:
Replaced code that gave the historical BSD behaviour of removing one
link name by checks that this code is now unreachable. This fixes
some races. All vnodes needed to be unlocked for the removal, and
locking at another level using something like IN_RENAME was not even
attempted, so it was possible for rename(x, y) to return with both x
and y removed even without any unlink(2) syscalls (one process can
remove x using rename(x, y) and another process can remove y using
rename(y, x)).
Prodded by: alfred
MFC after: 8 weeks
PR: 42617
layers deep in <sys/proc.h> or <sys/vnode.h>.
Include <sys/vmmeter.h> instead of depending on namespace pollution in
<sys/pcpu.h>.
Sorted includes as much as possible.
pmap_zero_page() and pmap_zero_page_area() were modified to accept
a struct vm_page * instead of a physical address, vm_page_zero_fill()
and vm_page_zero_fill_area() have served no purpose.
make a series of modifications to the credential arguments relating
to file read and write operations to cliarfy which credential is
used for what:
- Change fo_read() and fo_write() to accept "active_cred" instead of
"cred", and change the semantics of consumers of fo_read() and
fo_write() to pass the active credential of the thread requesting
an operation rather than the cached file cred. The cached file
cred is still available in fo_read() and fo_write() consumers
via fp->f_cred. These changes largely in sys_generic.c.
For each implementation of fo_read() and fo_write(), update cred
usage to reflect this change and maintain current semantics:
- badfo_readwrite() unchanged
- kqueue_read/write() unchanged
pipe_read/write() now authorize MAC using active_cred rather
than td->td_ucred
- soo_read/write() unchanged
- vn_read/write() now authorize MAC using active_cred but
VOP_READ/WRITE() with fp->f_cred
Modify vn_rdwr() to accept two credential arguments instead of a
single credential: active_cred and file_cred. Use active_cred
for MAC authorization, and select a credential for use in
VOP_READ/WRITE() based on whether file_cred is NULL or not. If
file_cred is provided, authorize the VOP using that cred,
otherwise the active credential, matching current semantics.
Modify current vn_rdwr() consumers to pass a file_cred if used
in the context of a struct file, and to always pass active_cred.
When vn_rdwr() is used without a file_cred, pass NOCRED.
These changes should maintain current semantics for read/write,
but avoid a redundant passing of fp->f_cred, as well as making
it more clear what the origin of each credential is in file
descriptor read/write operations.
Follow-up commits will make similar changes to other file descriptor
operations, and modify the MAC framework to pass both credentials
to MAC policy modules so they can implement either semantic for
revocation.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
parts rather than use vop_{read,write}_args. Access to these
functions will ultimately not be available through the
"vop_{read,write}+IO_EXT" API but this functionality is retained
for debugging purposes for now.
Sponsored by: DARPA & NAI Labs.
UFS only thing, and FFS should in principle not know if it is enabled
or not.
This commit cleans ffs_vnops.c for such knowledge, but not ffs_vfsops.c
Sponsored by: DARPA and NAI Labs.
these in the main filesystems. This does not change the resulting code
but makes the source a little bit more grepable.
Sponsored by: DARPA and NAI Labs.
enforcement of MAC policy on the read or write operations:
- In ext2fs, don't enforce MAC on loop-back reads and writes supporting
directory read operations in lookup(), directory modifications in
rename(), directory write operations in mkdir(), symlink write
operations in symlink().
- In the NFS client locking code, perform vn_rdwr() on the NFS locking
socket without enforcing MAC, since the write is done on behalf of
the kernel NFS implementation rather than the user process.
- In UFS, don't enforce MAC on loop-back reads and writes supporting
directory read operations in lookup(), and symlink write operations
in symlink().
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
- v_vflag is protected by the vnode lock and is used when synchronization
with VOP calls is needed.
- v_iflag is protected by interlock and is used for dealing with vnode
management issues. These flags include X/O LOCK, FREE, DOOMED, etc.
- All accesses to v_iflag and v_vflag have either been locked or marked with
mp_fixme's.
- Many ASSERT_VOP_LOCKED calls have been added where the locking was not
clear.
- Many functions in vfs_subr.c were restructured to provide for stronger
locking.
Idea stolen from: BSD/OS
kernel access control.
Instrument UFS to support per-inode MAC labels. In particular,
invoke MAC framework entry points for generically supporting the
backing of MAC labels into extended attributes. This ends up
introducing new vnode operation vector entries point at the MAC
framework entry points, as well as some explicit entry point
invocations for file and directory creation events so that the
MAC framework can push labels to disk before the directory names
become persistent (this will work better once EAs in UFS2 are
hooked into soft updates). The generic EA MAC entry points
support executing with the file system in either single label
or multilabel operation, and will fall back to the mount label
if multilabel is not specified at mount-time.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
