Commit Graph

1844 Commits

Author SHA1 Message Date
Konstantin Belousov
ddd6b3fc33 Add flags argument to vfs_write_resume() and remove
vfs_write_resume_flags().

Sponsored by:	The FreeBSD Foundation
2013-01-11 06:08:32 +00:00
Konstantin Belousov
f99cb34c4f The process_deferred_inactive() function locks the vnodes of the ufs
mount, which means that is must not be called while the snaplock is
owned.  The vfs_write_resume(9) does call the function as the
VFS_SUSP_CLEAN() method, which is too early and falls into the region
still protected by snaplock.

Add yet another flag for the vfs_write_resume_flags() to avoid calling
suspension cleanup handler after the suspend is lifted, and use it in
the ffs_snapshot() call to vfs_write_resume.

Reported and tested by:	pho
Sponsored by:	The FreeBSD Foundation
MFC after:	2 weeks
2013-01-01 16:14:48 +00:00
Konstantin Belousov
91e9474552 Make it possible to atomically resume writes on the mount and account
the write start, by adding a variation of the vfs_write_resume(9)
which accepts flags.

Use the new function to prevent a deadlock between parallel suspension
and snapshotting a UFS mount.  The ffs_snapshot() code performed
vfs_write_resume() followed by vn_start_write() while owning the
snaplock.  If the suspension intervene between resume and
vn_start_write(), the deadlock occured after the suspending thread
tried to lock the snaplock, most typically during the write in the
ffs_copyonwrite().

Reported and tested by:	Andreas Longwitz <longwitz@incore.de>
Reviewed by:	mckusick
MFC after:	2 weeks
X-MFC-note:	make the vfs_write_resume(9) function a macro after the MFC,
	in HEAD
2012-12-28 23:08:30 +00:00
Attilio Rao
b1308d72c2 Fixup r218424: uio_yield() was scaling directly to userland priority.
When kern_yield() was introduced with the possibility to specify
a new priority, the behaviour changed by not lowering priority at all
in the consumers, making the yielding mechanism highly ineffective for
high priority kthreads like bufdaemon, syncer, vlrudaemon, etc.
There are no evidences that consumers could bear with such change in
semantic and this situation could finally lead to bugs similar to the
ones fixed in r244240.
Re-specify userland pri for kthreads involved.

Tested by:	pho
Reviewed by:	kib, mdf
MFC after:	1 week
2012-12-21 13:14:12 +00:00
Konstantin Belousov
9f37ee804a Fix a typo, resulting in the NULL pointer dereference.
Reported and tested by:	pho
Sponsored by:	The FreeBSD Foundation
MFC after:	3 days
2012-12-15 02:03:59 +00:00
Attilio Rao
c6e0355cee r16312 is not any longer real since many years (likely since when VFS
received granular locking) but the comment present in UFS has been
copied all over other filesystems code incorrectly for several times.

Removes comments that makes no sense now.

Reviewed by:	kib
MFC after:	3 days
2012-11-19 22:43:45 +00:00
Edward Tomasz Napierala
213a71c68b Fix build of kdump(1). 2012-11-18 22:03:31 +00:00
Edward Tomasz Napierala
1848286ada Add UFS writesuspension mechanism, designed to allow userland processes
to modify on-disk metadata for filesystems mounted for write.

Reviewed by:	kib, mckusick
Sponsored by:	FreeBSD Foundation
2012-11-18 18:57:19 +00:00
Jeff Roberson
ad9cdc05ba - Fix a truncation bug with softdep journaling that could leak blocks on
crash.  When truncating a file that never made it to disk we use the
   canceled allocation dependencies to hold the journal records until
   the truncation completes.  Previously allocdirect dependencies on
   the id_bufwait list were not considered and their journal space
   could expire before the bitmaps were written.  Cancel them and attach
   them to the freeblks as we do for other allocdirects.
 - Add KTR traces that were used to debug this problem.
 - When adding jsegdeps, always use jwork_insert() so we don't have more
   than one segdep on a given jwork list.

Sponsored by:	EMC / Isilon Storage Division
2012-11-14 06:37:43 +00:00
Jeff Roberson
b2c29d39cd - Fix a bug that has existed since the original softdep implementation.
When a background copy of a cg is written we complete any work associated
   with that bmsafemap.  If new work has been added to the non-background
   copy of the buffer it will be completed before the next write happens.
   The solution is to do the rollbacks when we make the copy so only those
   dependencies that were present at the time of writing will be completed
   when the background write completes.  This would've resulted in various
   bitmap related corruptions and panics.  It also would've expired journal
   entries early causing journal replay to miss some records.

MFC after:	2 weeks
2012-11-12 19:53:55 +00:00
Attilio Rao
bc2258da88 Complete MPSAFE VFS interface and remove MNTK_MPSAFE flag.
Porters should refer to __FreeBSD_version 1000021 for this change as
it may have happened at the same timeframe.
2012-11-09 18:02:25 +00:00
Jeff Roberson
53cc0bebb9 - Correct rev 242734, segments can sometimes get stuck. Be a bit more
defensive with segment state.

Reported by:	 b. f. <bf1783@googlemail.com>
2012-11-09 04:04:25 +00:00
Jeff Roberson
40b43503c0 - Implement BIO_FLUSH support around journal entries. This will not 100%
solve power loss problems with dishonest write caches.  However, it
   should improve the situation and force a full fsck when it is unable
   to resolve with the journal.
 - Resolve a case where the journal could wrap in an unsafe way causing
   us to prematurely lose journal entries in very specific scenarios.

Discussed with:	mckusick
MFC after:	1 month
2012-11-08 01:41:04 +00:00
Kirk McKusick
aa7ddc85c7 When a file is first being written, the dynamic block reallocation
(implemented by ffs_reallocblks_ufs[12]) relocates the file's blocks
so as to cluster them together into a contiguous set of blocks on
the disk.

When the cluster crosses the boundary into the first indirect block,
the first indirect block is initially allocated in a position
immediately following the last direct block.  Block reallocation
would usually destroy locality by moving the indirect block out of
the way to keep the data blocks contiguous.  This change compensates
for this problem by noting that the first indirect block should be
left immediately following the last direct block.  It then tries
to start a new cluster of contiguous blocks (referenced by the
indirect block) immediately following the indirect block.

We should also do this for other indirect block boundaries, but it
is only important for the first one.

Suggested by: Bruce Evans
MFC:          2 weeks
2012-11-03 18:55:55 +00:00
Jeff Roberson
6d95eb4c5f - In cancel_mkdir_dotdot don't panic if the inodedep is not available. If
the previous diradd had already finished it could have been reclaimed
   already.  This would only happen under heavy dependency pressure.

Reported by:	Andrey Zonov <zont@FreeBSD.org>
Discussed with:	mckusick
MFC after:	1 week
2012-11-02 21:04:06 +00:00
Konstantin Belousov
140dedb81c The r241025 fixed the case when a binary, executed from nullfs mount,
was still possible to open for write from the lower filesystem.  There
is a symmetric situation where the binary could already has file
descriptors opened for write, but it can be executed from the nullfs
overlay.

Handle the issue by passing one v_writecount reference to the lower
vnode if nullfs vnode has non-zero v_writecount.  Note that only one
write reference can be donated, since nullfs only keeps one use
reference on the lower vnode.  Always use the lower vnode v_writecount
for the checks.

Introduce the VOP_GET_WRITECOUNT to read v_writecount, which is
currently always bypassed to the lower vnode, and VOP_ADD_WRITECOUNT
to manipulate the v_writecount value, which manages a single bypass
reference to the lower vnode.  Caling the VOPs instead of directly
accessing v_writecount provide the fix described in the previous
paragraph.

Tested by:	pho
MFC after:	3 weeks
2012-11-02 13:56:36 +00:00
Edward Tomasz Napierala
549f62fa42 Fix problem with geom_label(4) not recognizing UFS labels on filesystems
extended using growfs(8).  The problem here is that geom_label checks if
the filesystem size recorded in UFS superblock is equal to the provider
(i.e. device) size.  This check cannot be removed due to backward
compatibility.  On the other hand, in most cases growfs(8) cannot set
fs_size in the superblock to match the provider size, because, differently
from newfs(8), it cannot recompute cylinder group sizes.

To fix this problem, add another superblock field, fs_providersize, used
only for this purpose.  The geom_label(4) will attach if either fs_size
(filesystem created with newfs(8)) or fs_providersize (filesystem expanded
using growfs(8)) matches the device size.

PR:		kern/165962
Reviewed by:	mckusick
Sponsored by:	FreeBSD Foundation
2012-10-30 21:32:10 +00:00
Edward Tomasz Napierala
f1988d463c Fix two problems that caused instant panic when the device mounted
with softupdates went away.  Note that this does not fix the problem
entirely; I'm committing it now to make it easier for someone to pick
up the work.

Reviewed by:	mckusick
2012-10-28 18:53:28 +00:00
Konstantin Belousov
5050aa86cf Remove the support for using non-mpsafe filesystem modules.
In particular, do not lock Giant conditionally when calling into the
filesystem module, remove the VFS_LOCK_GIANT() and related
macros. Stop handling buffers belonging to non-mpsafe filesystems.

The VFS_VERSION is bumped to indicate the interface change which does
not result in the interface signatures changes.

Conducted and reviewed by:	attilio
Tested by:	pho
2012-10-22 17:50:54 +00:00
Matthew D Fleming
fc8fdae0df Fix up kernel sources to be ready for a 64-bit ino_t.
Original code by:	Gleb Kurtsou
2012-09-27 23:30:49 +00:00
Mateusz Guzik
1ec9bedabe Remove unused member of struct indir (in_exists) from UFS and EXT2 code.
Reviewed by:	mckusick
Approved by:	trasz (mentor)
MFC after:	1 week
2012-08-17 17:45:27 +00:00
Konstantin Belousov
1c771f9222 After the PHYS_TO_VM_PAGE() function was de-inlined, the main reason
to pull vm_param.h was removed.  Other big dependency of vm_page.h on
vm_param.h are PA_LOCK* definitions, which are only needed for
in-kernel code, because modules use KBI-safe functions to lock the
pages.

Stop including vm_param.h into vm_page.h. Include vm_param.h
explicitely for the kernel code which needs it.

Suggested and reviewed by:	alc
MFC after:    2 weeks
2012-08-05 14:11:42 +00:00
Kevin Lo
f7a3729c91 Use NULL instead of 0 for pointers 2012-07-22 15:40:31 +00:00
Konstantin Belousov
c5c1199c83 Extend the KPI to lock and unlock f_offset member of struct file. It
now fully encapsulates all accesses to f_offset, and extends f_offset
locking to other consumers that need it, in particular, to lseek() and
variants of getdirentries().

Ensure that on 32bit architectures f_offset, which is 64bit quantity,
always read and written under the mtxpool protection. This fixes
apparently easy to trigger race when parallel lseek()s or lseek() and
read/write could destroy file offset.

The already broken ABI emulations, including iBCS and SysV, are not
converted (yet).

Tested by:	pho
No objections from:	jhb
MFC after:    3 weeks
2012-07-02 21:01:03 +00:00
Konstantin Belousov
7aac7bc18a Fix unbounded-length malloc, controlled from usermode. The added check
is performed before exact size of the buffer is calculated, but the
buffer cannot have size greater then the total space allocated for
extended attributes. The existing check is executing with precise
size, but it is too late, since buffer needs to be allocated in
advance.

Also, adapt to uio_resid being of ssize_t type.  Use lblktosize instead of
multiplying by fs block size by hand as well.

Reported and tested by:	  pho
MFC after:   1 week
2012-06-21 09:20:07 +00:00
Kirk McKusick
aa445c9d7c In softdep_setup_inomapdep() we may have to allocate both inodedep
and bmsafemap dependency structures in inodedep_lookup() and
bmsafemap_lookup() respectively. The setup of these structures must
be done while holding the soft-dependency mutex. If the inodedep is
allocated first, it may be freed in the I/O completion callback when
the mutex is released to allocate the bmsafemap. If the bmsafemap is
allocated first, it may be freed in the I/O completion callback when
the mutex is released to allocate the inodedep.

To resolve this problem, bmsafemap_lookup has had a parameter added
that allows a pre-malloc'ed bmsafemap to be passed in so that it does
not need to release the mutex to create a new bmsafemap. The
softdep_setup_inomapdep() routine pre-malloc's a bmsafemap dependency
before acquiring the mutex and starting to build the inodedep with a
call to inodedep_lookup(). The subsequent call to bmsafemap_lookup()
is passed this pre-allocated bmsafemap entry so that it need not
release the mutex if it needs to create a new one.

Reported by: Peter Holm
Tested by:   Peter Holm
MFC after:   1 week
2012-06-11 23:07:21 +00:00
Konstantin Belousov
b569050a78 Enable vn_io_fault() lock avoidance for UFS.
Tested by:	pho
MFC after:	2 months
2012-05-30 16:45:41 +00:00
Konstantin Belousov
6ee10a96c0 Implement SEEK_HOLE/SEEK_DATA for UFS.
MFC after:	2 weeks
2012-05-26 05:29:53 +00:00
Kirk McKusick
8b6207110d Add missing `continue' statement at end of case.
Found by:  Kevin Lo (kevlo@)
MFC after: 1 week
2012-05-18 15:20:21 +00:00
Edward Tomasz Napierala
06c65b6b41 Remove unused thread argument from ufs_extattr_uepm_lock()/ufs_extattr_uepm_unlock(). 2012-04-23 17:56:35 +00:00
Edward Tomasz Napierala
05cc75de83 Fix build. 2012-04-23 17:54:49 +00:00
Edward Tomasz Napierala
26621e1f06 Remove unused thread argument from clear_inodeps() and clear_remove(). 2012-04-23 14:44:18 +00:00
Edward Tomasz Napierala
af6e6b87ad Remove unused thread argument to vrecycle().
Reviewed by:	kib
2012-04-23 14:10:34 +00:00
Edward Tomasz Napierala
c52fd858ae Remove unused thread argument from vtruncbuf().
Reviewed by:	kib
2012-04-23 13:21:28 +00:00
Edward Tomasz Napierala
72b8ff1c74 Fix use-after-free introduced in r234036.
Reviewed by:	mckusick
Tested by:	pho
2012-04-21 10:45:46 +00:00
Kirk McKusick
dca5e0ec50 This update uses the MNT_VNODE_FOREACH_ACTIVE interface that loops
over just the active vnodes associated with a mount point to replace
MNT_VNODE_FOREACH_ALL in the vfs_msync, ffs_sync_lazy, and qsync
routines.

The vfs_msync routine is run every 30 seconds for every writably
mounted filesystem. It ensures that any files mmap'ed from the
filesystem with modified pages have those pages queued to be
written back to the file from which they are mapped.

The ffs_lazy_sync and qsync routines are run every 30 seconds for
every writably mounted UFS/FFS filesystem. The ffs_lazy_sync routine
ensures that any files that have been accessed in the previous
30 seconds have had their access times queued for updating in the
filesystem. The qsync routine ensures that any files with modified
quotas have those quotas queued to be written back to their
associated quota file.

In a system configured with 250,000 vnodes, less than 1000 are
typically active at any point in time. Prior to this change all
250,000 vnodes would be locked and inspected twice every minute
by the syncer. For UFS/FFS filesystems they would be locked and
inspected six times every minute (twice by each of these three
routines since each of these routines does its own pass over the
vnodes associated with a mount point). With this change the syncer
now locks and inspects only the tiny set of vnodes that are active.

Reviewed by: kib
Tested by:   Peter Holm
MFC after:   2 weeks
2012-04-20 07:00:28 +00:00
Jaakko Heinonen
808dd116cb The part about exec atime no longer applies in the comment.
Pointed out by:	bde
2012-04-18 15:19:00 +00:00
Kirk McKusick
71469bb38f Replace the MNT_VNODE_FOREACH interface with MNT_VNODE_FOREACH_ALL.
The primary changes are that the user of the interface no longer
needs to manage the mount-mutex locking and that the vnode that
is returned has its mutex locked (thus avoiding the need to check
to see if its is DOOMED or other possible end of life senarios).

To minimize compatibility issues for third-party developers, the
old MNT_VNODE_FOREACH interface will remain available so that this
change can be MFC'ed to 9. Following the MFC to 9, MNT_VNODE_FOREACH
will be removed in head.

The reason for this update is to prepare for the addition of the
MNT_VNODE_FOREACH_ACTIVE interface that will loop over just the
active vnodes associated with a mount point (typically less than
1% of the vnodes associated with the mount point).

Reviewed by: kib
Tested by:   Peter Holm
MFC after:   2 weeks
2012-04-17 16:28:22 +00:00
Kirk McKusick
ecb6e528c5 Export vinactive() from kern/vfs_subr.c (e.g., make it no longer
static and declare its prototype in sys/vnode.h) so that it can be
called from process_deferred_inactive() (in ufs/ffs/ffs_snapshot.c)
instead of the body of vinactive() being cut and pasted into
process_deferred_inactive().

Reviewed by: kib
MFC after:   2 weeks
2012-04-11 23:01:11 +00:00
Jaakko Heinonen
fce74feae1 - Return EPERM from ufs_setattr() when an user without PRIV_VFS_SYSFLAGS
privilege attempts to toggle SF_SETTABLE flags.
- Use the '^' operator in the SF_SNAPSHOT anti-toggling check.

Flags are now stored to ip->i_flags in one place after all checks.

Submitted by:	bde
2012-04-10 15:59:37 +00:00
Edward Tomasz Napierala
2b028c25d3 Fix panic in ffs_reload(), which may happen when read-only filesystem
gets resized and then reloaded.

Reviewed by:	kib, mckusick (earlier version)
Sponsored by:	The FreeBSD Foundation
2012-04-08 13:44:55 +00:00
Kirk McKusick
b73ffa31d4 Drop an unnecessary setting of si_mountpt when updating a UFS mount point.
Clearly it must have been set when the mount was done.

Reviewed by: kib
2012-04-08 06:14:49 +00:00
Jaakko Heinonen
63dfd849a1 Add a check for unsupported file flags to ufs_setattr().
Discussed with:	bde
MFC after:	2 weeks
2012-04-04 14:50:21 +00:00
Kirk McKusick
23d6e518da A file cannot be deallocated until its last name has been removed
and it is no longer referenced by a user process. The inode for a
file whose name has been removed, but is still referenced at the
time of a crash will still be allocated in the filesystem, but will
have no references (e.g., they will have no names referencing them
from any directory).

With traditional soft updates these unreferenced inodes will be
found and reclaimed when the background fsck is run. When using
journaled soft updates, the kernel must keep track of these inodes
so that it can find and reclaim them during the cleanup process.
Their existence cannot be stored in the journal as the journal only
handles short-term events, and they may persist for days. So, they
are tracked by keeping them in a linked list whose head pointer is
stored in the superblock. The journal tracks them only until their
linked list pointers have been commited to disk. Part of the cleanup
process involves traversing the list of unreferenced inodes and
reclaiming them.

This bug was triggered when confusion arose in the commit steps
of keeping the unreferenced-inode linked list coherent on disk.
Notably, a race between the link() system call adding a link-count
to a file and the unlink() system call removing a link-count to
the file. Here if the unlink() ran after link() had looked up
the file but before link() had incremented the link-count of the
file, the file's link-count would drop to zero before the link()
incremented it back up to one. If the file was referenced by a
user process, the first transition through zero made it appear
that it should be added to the unreferenced-inode list when in
fact it should not have been added. If the new name created by
link() was deleted within a few seconds (with the file still
referenced by a user process) it would legitimately be a candidate
for addition to the unreferenced-inode list. The result was that
there were two attempts to add the same inode to the unreferenced-inode
list which scrambled the unreferenced-inode list's pointers leading
to a panic. The fix is to detect and avoid the false attempt at
adding it to the unreferenced-inode list by having the link()
system call check to see if the link count is zero before it
increments it. If it is, the link() fails with ENOENT (showing that
it has failed the link()/unlink() race).

While tracking down this bug, we have added additional assertions
to detect the problem sooner and also simplified some of the code.

Reported by:      Kirk Russell
Fix submitted by: Jeff Roberson
Tested by:        Peter Holm
PR:               kern/159971
MFC (to 9 only):  2 weeks
2012-04-02 21:58:37 +00:00
Jaakko Heinonen
fccf286d24 - Use more natural ip->i_flags instead of vap->va_flags in the final
flags check.
- Add a comment for the immutable/append check done after handling of
  the flags.
- Style improvements.

No functional change intended.

Submitted by:	bde
MFC after:	2 weeks
2012-04-02 16:33:21 +00:00
Kirk McKusick
6c09f4a27c A refinement of change 232351 to avoid a race with a forcible unmount.
While we have a snapshot vnode unlocked to avoid a deadlock with another
inode in the same inode block being updated, the filesystem containing
it may be forcibly unmounted. When that happens the snapshot vnode is
revoked. We need to check for that condition and fail appropriately.

This change will be included along with 232351 when it is MFC'ed to 9.

Spotted by:  kib
Reviewed by: kib
2012-03-28 21:21:19 +00:00
Kirk McKusick
1faacf5d09 Keep track of the mount point associated with a special device
to enable the collection of counts of synchronous and asynchronous
reads and writes for its associated filesystem. The counts are
displayed using `mount -v'.

Ensure that buffers used for paging indicate the vnode from
which they are operating so that counts of paging I/O operations
from the filesystem are collected.

This checkin only adds the setting of the mount point for the
UFS/FFS filesystem, but it would be trivial to add the setting
and clearing of the mount point at filesystem mount/unmount
time for other filesystems too.

Reviewed by: kib
2012-03-28 20:49:11 +00:00
Konstantin Belousov
ea573a50b3 Do trivial reformatting of the comment to record the missed commit
message for r233609:
Restore the writes of atimes, quotas and superblock from syncer vnode.

Noted by:   rdivacky
2012-03-28 14:16:15 +00:00
Konstantin Belousov
a988a5c609 Reviewed by: bde, mckusick
Tested by:	pho
MFC after:	2 weeks
2012-03-28 14:06:47 +00:00
Konstantin Belousov
64c8ead942 Microoptimize: in qsync loop over mount vnodes, only unlock mount
interlock after we committed to try to vget() the vnode.

Submitted by:	bde
Reviewed by:	mckusick
Tested by:	pho
MFC after:	1 week
2012-03-28 13:56:18 +00:00