Commit Graph

59 Commits

Author SHA1 Message Date
Will Andrews e6cfd633be Illumos 3749 - zfs event processing should work on R/O root filesystems
3749 zfs event processing should work on R/O root filesystems
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Eric Schrock <eric.schrock@delphix.com>
Approved by: Christopher Siden <christopher.siden@delphix.com>

References:
  https://www.illumos.org/issues/3749
  https://github.com/illumos/illumos-gate/commit/3cb69f7

Porting notes:
- [include/sys/spa_impl.h]
  - ffe9d38 Add generic errata infrastructure
  - 1421c89 Add visibility in to arc_read
- [include/sys/fm/fs/zfs.h]
  - 2668527 Add linux events
  - 6283f55 Support custom build directories and move includes
- [module/zfs/spa_config.c]
  - Updated spa_config_sync() to match illumos with the exception
    of a Linux specific block.

Ported-by: kernelOfTruth kerneloftruth@gmail.com
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2016-01-12 14:42:32 -08:00
Brian Behlendorf b870c7e5f4 Revert "Illumos 3749 - zfs event processing should work on R/O root filesystems"
This reverts commit b47637ecdc which
introduced a regression in ztest.

$ ./cmd/ztest/ztest -V
5 vdevs, 7 datasets, 23 threads, 300 seconds...
*** Error in `/rpool/home/behlendo/src/git/zfs/cmd/ztest/.libs/lt-ztest':
double free or corruption (fasttop): 0x0000000000d339f0 ***
2016-01-11 14:10:30 -08:00
Will Andrews b47637ecdc Illumos 3749 - zfs event processing should work on R/O root filesystems
3749 zfs event processing should work on R/O root filesystems
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Eric Schrock <eric.schrock@delphix.com>
Approved by: Christopher Siden <christopher.siden@delphix.com>

References:
  https://www.illumos.org/issues/3749
  https://github.com/illumos/illumos-gate/commit/3cb69f7

Porting notes:
- [include/sys/spa_impl.h]
  - ffe9d38 Add generic errata infrastructure
  - 1421c89 Add visibility in to arc_read
- [include/sys/fm/fs/zfs.h]
  - 2668527 Add linux events
  - 6283f55 Support custom build directories and move includes
- [module/zfs/spa_config.c]
  - Updated spa_config_sync() to match illumos with the exception
    of a Linux specific block.

Ported-by: kernelOfTruth kerneloftruth@gmail.com
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2016-01-11 09:23:37 -08:00
Turbo Fredriksson d050c627b5 Improve on the ZFS events documentation
* Add information about the 'zpool events' command in zpool(8).
* More events and payloads defined in zfs-events(5).
* I/O Stages and I/O Flags sections added.
* Remove unused legacy "zio_deadline" payload define.

Signed-off-by: Turbo Fredriksson <turbo@bayour.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #3467
2015-06-09 11:19:19 -07:00
Richard Yao 3cd33ffc3b Kernel header installation should respect --prefix
This is the upstream component of work that enables preliminary support
for building Gentoo's ZFS packaging on other Linux systems via Gentoo
Prefix.

Signed-off-by: Richard Yao <richard.yao@clusterhq.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #2641
2014-10-28 09:37:06 -07:00
Isaac Huang 0426c16804 Fixed memory leaks in zevent handling
Some nvlist_t could be leaked in error handling paths.
Also make sure cb argument to zfs_zevent_post() cannnot
be NULL.

Signed-off-by: Isaac Huang <he.huang@intel.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #2158
2014-08-20 10:45:16 -07:00
Brian Behlendorf 904ea2763e Add automatic hot spare functionality
When a vdev starts getting I/O or checksum errors it is now
possible to automatically rebuild to a hot spare device.

To cleanly support this functionality in a shell script some
additional information was added to all zevent ereports which
include a vdev.  This covers both io and checksum zevents but
may be used but other scripts.

In the Illumos FMA solution the same information is required
but it is retrieved through the libzfs library interface.
Specifically the following members were added:

  vdev_spare_paths  - List of vdev paths for all hot spares.
  vdev_spare_guids  - List of vdev guids for all hot spares.
  vdev_read_errors  - Read errors for the problematic vdev
  vdev_write_errors - Write errors for the problematic vdev
  vdev_cksum_errors - Checksum errors for the problematic vdev.

By default the required hot spare scripts are installed but this
functionality is disabled.  To enable hot sparing uncomment the
ZED_SPARE_ON_IO_ERRORS and ZED_SPARE_ON_CHECKSUM_ERRORS in the
/etc/zfs/zed.d/zed.rc configuration file.

These scripts do no add support for the autoexpand property. At
a minimum this requires adding a new udev rule to detect when
a new device is added to the system.  It also requires that the
autoexpand policy be ported from Illumos, see:

  https://github.com/illumos/illumos-gate/blob/master/usr/src/cmd/syseventd/modules/zfs_mod/zfs_mod.c

Support for detecting the correct name of a vdev when it's not
a whole disk was added by Turbo Fredriksson.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Chris Dunlap <cdunlap@llnl.gov>
Signed-off-by: Turbo Fredriksson <turbo@bayour.com>
Issue #2
2014-04-02 13:10:08 -07:00
Brian Behlendorf 75e3ff58fe Add zpool_events_seek() functionality
The ZFS_IOC_EVENTS_SEEK ioctl was added to allow user space callers
to seek around the zevent file descriptor by EID.  When a specific
EID is passed and it exists the cursor will be positioned there.
If the EID is no longer cached by the kernel ENOENT is returned.
The caller may also pass ZEVENT_SEEK_START or ZEVENT_SEEK_END to seek
to those respective locations.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Chris Dunlap <cdunlap@llnl.gov>
Issue #2
2014-03-31 16:10:57 -07:00
Brian Behlendorf a2f1945ee3 Add a unique "eid" value to all zevents
Tagging each zevent with a unique monotonically increasing EID
(Event IDentifier) provides the required infrastructure for a user
space daemon to reliably process zevents.  By writing the EID to
persistent storage the daemon can safely resume where it left off
in the event stream when it's restarted.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Chris Dunlap <cdunlap@llnl.gov>
Issue #2
2014-03-31 16:10:41 -07:00
Michael Kjorling d1d7e2689d cstyle: Resolve C style issues
The vast majority of these changes are in Linux specific code.
They are the result of not having an automated style checker to
validate the code when it was originally written.  Others were
caused when the common code was slightly adjusted for Linux.

This patch contains no functional changes.  It only refreshes
the code to conform to style guide.

Everyone submitting patches for inclusion upstream should now
run 'make checkstyle' and resolve any warning prior to opening
a pull request.  The automated builders have been updated to
fail a build if when 'make checkstyle' detects an issue.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #1821
2013-12-18 16:46:35 -08:00
George.Wilson cc92e9d0c3 3246 ZFS I/O deadman thread
Reviewed by: Matt Ahrens <matthew.ahrens@delphix.com>
Reviewed by: Eric Schrock <eric.schrock@delphix.com>
Reviewed by: Christopher Siden <chris.siden@delphix.com>
Approved by: Garrett D'Amore <garrett@damore.org>

NOTES: This patch has been reworked from the original in the
following ways to accomidate Linux ZFS implementation

*) Usage of the cyclic interface was replaced by the delayed taskq
   interface.  This avoids the need to implement new compatibility
   code and allows us to rely on the existing taskq implementation.

*) An extern for zfs_txg_synctime_ms was added to sys/dsl_pool.h
   because declaring externs in source files as was done in the
   original patch is just plain wrong.

*) Instead of panicing the system when the deadman triggers a
   zevent describing the blocked vdev and the first pending I/O
   is posted.  If the panic behavior is desired Linux provides
   other generic methods to panic the system when threads are
   observed to hang.

*) For reference, to delay zios by 30 seconds for testing you can
   use zinject as follows: 'zinject -d <vdev> -D30 <pool>'

References:
  illumos/illumos-gate@283b84606b
  https://www.illumos.org/issues/3246

Ported-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #1396
2013-05-01 17:05:52 -07:00
Brian Behlendorf 775f2d34a3 Change zfs-kmod-devel install path
Install the common zfs kernel development headers under
/usr/src/zfs-<version>/ rather than in a kernel specific
directory.  The kernel specific build products such as
zfs_config.h and Modules.symvers are left installed under
/usr/src/zfs-<version>/<kernel>.

This was done to be consistent with where dkms expects
kernel module source to be packaged.  It also allows for
a common zfs-kmod-devel package which includes the headers,
and per-kernel zfs-kmod-devel-<kernel> packages.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2013-03-13 13:42:16 -07:00
George Wilson 32a9872bba Illumos #2671: zpool import should not fail if vdev ashift has increased
Reviewed by: Adam Leventhal <ahl@delphix.com>
Reviewed by: Eric Schrock <eric.schrock@delphix.com>
Reviewed by: Richard Elling <richard.elling@richardelling.com>
Reviewed by: Gordon Ross <gwr@nexenta.com>
Reviewed by: Garrett D'Amore <garrett@damore.org>
Approved by: Richard Lowe <richlowe@richlowe.net>

Refererces to Illumos issue:
      https://www.illumos.org/issues/2671

This patch has been slightly modified from the upstream Illumos
version.  In the upstream implementation a warning message is
logged to the console.  To prevent pointless console noise this
notification is now posted as a "ereport.fs.zfs.vdev.bad_ashift"
event.

The event indicates a non-optimial (but entirely safe) ashift
value was used to create the pool.  Depending on your workload
this may impact pool performance.  Unfortunately, the only way
to correct the issue is to recreate the pool with a new ashift.

NOTE: The unrelated fix to the comment in zpool_main.c appears
in the upstream commit and was preserved for consistnecy.

Ported-by: Cyril Plisko <cyril.plisko@mountall.com>
Reworked-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #955
2012-11-15 11:05:59 -08:00
Brian Behlendorf 9dcb971983 Log I/Os longer than zio_delay_max (30s default)
There have been reports of ZFS deadlocking due to what appears to
be a lost IO.  This patch addes some debugging to determine the
exact state of the IO which neither 1) completed, 2) failed, or
3) timed out after zio_delay_max (30) seconds.

This information will be logged using the ZFS FMA infrastructure
as a 'delay' event and posted to the internal zevent log.  By
default the last 64 events will be kept in the log but the limit
is configurable via the zfs_zevent_len_max module option.

To dump the contents of the log use the 'zpool events -v' command
and look for the resource.fs.zfs.delay event.  It will include
various information about the pool, vdev, and zio which may shed
some light on the issue.

In the context of this change the 120 second kernel blocked thread
watchdog has been disabled for synchronous IOs.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #930
2012-11-02 15:45:59 -07:00
Brian Behlendorf ca8b5af89d Remove autotools products
Remove all of the generated autotools products from the repository
and update the .gitignore files accordingly.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #718
2012-08-27 11:47:44 -07:00
Etienne Dechamps ee5fd0bb80 Set zvol discard_granularity to the volblocksize.
Currently, zvols have a discard granularity set to 0, which suggests to
the upper layer that discard requests of arbirarily small size and
alignment can be made efficiently.

In practice however, ZFS does not handle unaligned discard requests
efficiently: indeed, it is unable to free a part of a block. It will
write zeros to the specified range instead, which is both useless and
inefficient (see dnode_free_range).

With this patch, zvol block devices expose volblocksize as their discard
granularity, so the upper layer is aware that it's not supposed to send
discard requests smaller than volblocksize.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #862
2012-08-07 14:55:31 -07:00
Richard Yao 739a1a82e0 Linux 3.5 compat, end_writeback() changed to clear_inode()
The end_writeback() function was changed by moving the call to
inode_sync_wait() earlier in to evict().   This effecitvely changes
the ordering of the sync but it does not impact the details of
the zfs implementation.

However, as part of this change end_writeback() was renamed to
clear_inode() to reflect the new semantics.  This change does
impact us and clear_inode() now maps to end_writeback() for
kernels prior to 3.5.

Signed-off-by: Richard Yao <ryao@cs.stonybrook.edu>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #784
2012-07-23 12:29:36 -07:00
Richard Yao ea1fdf46e2 Linux 3.5 compat, iops->truncate_range() removed
The vmtruncate_range() support has been removed from the kernel in
favor of using the fallocate method in the file_operations table.

Signed-off-by: Richard Yao <ryao@cs.stonybrook.edu>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #784
2012-07-23 12:29:32 -07:00
Richard Yao 756c3e5a9c Linux 3.5 compat, eops->encode_fh() takes inodes
The export_operations member ->encode_fh() has been updated to
take both the child and parent inodes.  This interface used to
take the child dentry and a bool describing if the parent is needed.

NOTE: While updating this code I noticed that we do not currently
cleanly handle the case where we're passed a connectable parent.
This code should be audited to make sure we're doing the right thing.

Signed-off-by: Richard Yao <ryao@cs.stonybrook.edu>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #784
2012-07-23 12:29:23 -07:00
Etienne Dechamps b5a28807cd Move partition scanning from userspace to module.
Currently, zpool online -e (dynamic vdev expansion) doesn't work on
whole disks because we're invoking ioctl(BLKRRPART) from userspace
while ZFS still has a partition open on the disk, which results in
EBUSY.

This patch moves the BLKRRPART invocation from the zpool utility to the
module. Specifically, this is done just before opening the device in
vdev_disk_open() which is called inside vdev_reopen(). This requires
jumping through some hoops to get to the disk device from the partition
device, and to make sure we can still open the partition after the
BLKRRPART call.

Note that this new code path is triggered on dynamic vdev expansion
only; other actions, like creating a new pool, are unchanged and still
call BLKRRPART from userspace.

This change also depends on API changes which are available in 2.6.37
and latter kernels.  The build system has been updated to detect this,
but there is no compatibility mode for older kernels.  This means that
online expansion will NOT be available in older kernels.  However, it
will still be possible to expand the vdev offline.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #808
2012-07-17 09:17:31 -07:00
Garrett D'Amore 3541dc6d02 Illumos #1748: desire support for reguid in zfs
Reviewed by: George Wilson <gwilson@zfsmail.com>
Reviewed by: Igor Kozhukhov <ikozhukhov@gmail.com>
Reviewed by: Alexander Eremin <alexander.eremin@nexenta.com>
Reviewed by: Alexander Stetsenko <ams@nexenta.com>
Approved by: Richard Lowe <richlowe@richlowe.net>

References:
  https://www.illumos.org/issues/1748

This commit modifies the user to kernel space ioctl ABI.  Extra
care should be taken when updating to ensure both the kernel
modules and utilities are updated.  If only the user space
component is updated both the 'zpool events' command and the
'zpool reguid' command will not work until the kernel modules
are updated.

Ported by:     Martin Matuska <martin@matuska.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #665
2012-07-11 13:08:56 -07:00
Richard Yao 6a0936babc Linux 3.4 compat, d_make_root() replaces d_alloc_root()
torvalds/linux@adc0e91ab1 introduced
introduced d_make_root() as a replacement for d_alloc_root(). Further
commits appear to have removed d_alloc_root() from the Linux source
tree. This causes the following failure:

  error: implicit declaration of function 'd_alloc_root'
  [-Werror=implicit-function-declaration]

To correct this we update the code to use the current d_make_root()
interface for readability.  Then we introduce an autotools check
to determine if d_make_root() is available.  If it isn't then we
define some compatibility logic which used the older d_alloc_root()
interface.

Signed-off-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #776
2012-06-11 10:04:49 -07:00
Brian Behlendorf b39d3b9f7b Linux 3.3 compat, iops->create()/mkdir()/mknod()
The mode argument of iops->create()/mkdir()/mknod() was changed from
an 'int' to a 'umode_t'.  To prevent a compiler warning an autoconf
check was added to detect the API change and then correctly set a
zpl_umode_t typedef.  There is no functional change.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #701
2012-04-30 12:52:38 -07:00
Brian Behlendorf 1c5de20ae2 Add --enable-debug-dmu-tx configure option
Allow rigorous (and expensive) tx validation to be enabled/disabled
indepentantly from the standard zfs debugging.  When enabled these
checks ensure that all txs are constructed properly and that a dbuf
is never dirtied without taking the correct tx hold.

This checking is particularly helpful when adding new dmu consumers
like Lustre.  However, for established consumers such as the zpl
with no known outstanding tx construction problems this is just
overhead.

--enable-debug-dmu-tx  - Enable/disable validation of each tx as
--disable-debug-dmu-tx   it is constructed.  By default validation
                         is disabled due to performance concerns.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2012-03-23 12:25:17 -07:00
Brian Behlendorf ebe7e575ea Add .zfs control directory
Add support for the .zfs control directory.  This was accomplished
by leveraging as much of the existing ZFS infrastructure as posible
and updating it for Linux as required.  The bulk of the core
functionality is now all there with the following limitations.

*) The .zfs/snapshot directory automount support requires a 2.6.37
   or newer kernel.  The exception is RHEL6.2 which has backported
   the d_automount patches.

*) Creating/destroying/renaming snapshots with mkdir/rmdir/mv
   in the .zfs/snapshot directory works as expected.  However,
   this functionality is only available to root until zfs
   delegations are finished.

      * mkdir - create a snapshot
      * rmdir - destroy a snapshot
      * mv    - rename a snapshot

The following issues are known defeciences, but we expect them to
be addressed by future commits.

*) Add automount support for kernels older the 2.6.37.  This should
   be possible using follow_link() which is what Linux did before.

*) Accessing the .zfs/snapshot directory via NFS is not yet possible.
   The majority of the ground work for this is complete.  However,
   finishing this work will require resolving some lingering
   integration issues with the Linux NFS kernel server.

*) The .zfs/shares directory exists but no futher smb functionality
   has yet been implemented.

Contributions-by: Rohan Puri <rohan.puri15@gmail.com>
Contributiobs-by: Andrew Barnes <barnes333@gmail.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #173
2012-03-22 13:03:47 -07:00
Brian Behlendorf 4b787d75c8 Cleanly support debug packages
Allow a source rpm to be rebuilt with debugging enabled.  This
avoids the need to have to manually modify the spec file.  By
default debugging is still largely disabled.  To enable specific
debugging features use the following options with rpmbuild.

  '--with debug'               - Enables ASSERTs

  # For example:
  $ rpmbuild --rebuild --with debug zfs-modules-0.6.0-rc6.src.rpm

Additionally, ZFS_CONFIG has been added to zfs_config.h for
packages which build against these headers.  This is critical
to ensure both zfs and the dependant package are using the same
prototype and structure definitions.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2012-02-27 14:08:17 -08:00
Etienne Dechamps 30930fba21 Add support for DISCARD to ZVOLs.
DISCARD (REQ_DISCARD, BLKDISCARD) is useful for thin provisioning.
It allows ZVOL clients to discard (unmap, trim) block ranges from
a ZVOL, thus optimizing disk space usage by allowing a ZVOL to
shrink instead of just grow.

We can't use zfs_space() or zfs_freesp() here, since these functions
only work on regular files, not volumes. Fortunately we can use the
low-level function dmu_free_long_range() which does exactly what we
want.

Currently the discard operation is not added to the log. That's not
a big deal since losing discard requests cannot result in data
corruption. It would however result in disk space usage higher than
it should be. Thus adding log support to zvol_discard() is probably
a good idea for a future improvement.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2012-02-09 16:19:38 -08:00
Etienne Dechamps cb2d19010d Support the fallocate() file operation.
Currently only the (FALLOC_FL_PUNCH_HOLE) flag combination is
supported, since it's the only one that matches the behavior of
zfs_space(). This makes it pretty much useless in its current
form, but it's a start.

To support other flag combinations we would need to modify
zfs_space() to make it more flexible, or emulate the desired
functionality in zpl_fallocate().

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #334
2012-02-09 16:19:32 -08:00
Etienne Dechamps 34037afe24 Improve ZVOL queue behavior.
The Linux block device queue subsystem exposes a number of configurable
settings described in Linux block/blk-settings.c. The defaults for these
settings are tuned for hard drives, and are not optimized for ZVOLs. Proper
configuration of these options would allow upper layers (I/O scheduler) to
take better decisions about write merging and ordering.

Detailed rationale:

 - max_hw_sectors is set to unlimited (UINT_MAX). zvol_write() is able to
   handle writes of any size, so there's no reason to impose a limit. Let the
   upper layer decide.

 - max_segments and max_segment_size are set to unlimited. zvol_write() will
   copy the requests' contents into a dbuf anyway, so the number and size of
   the segments are irrelevant. Let the upper layer decide.

 - physical_block_size and io_opt are set to the ZVOL's block size. This
   has the potential to somewhat alleviate issue #361 for ZVOLs, by warning
   the upper layers that writes smaller than the volume's block size will be
   slow.

 - The NONROT flag is set to indicate this isn't a rotational device.
   Although the backing zpool might be composed of rotational devices, the
   resulting ZVOL often doesn't exhibit the same behavior due to the COW
   mechanisms used by ZFS. Setting this flag will prevent upper layers from
   making useless decisions (such as reordering writes) based on incorrect
   assumptions about the behavior of the ZVOL.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2012-02-07 16:23:06 -08:00
Etienne Dechamps b18019d2d8 Fix synchronicity for ZVOLs.
zvol_write() assumes that the write request must be written to stable storage
if rq_is_sync() is true. Unfortunately, this assumption is incorrect. Indeed,
"sync" does *not* mean what we think it means in the context of the Linux
block layer. This is well explained in linux/fs.h:

    WRITE:       A normal async write. Device will be plugged.
    WRITE_SYNC:  Synchronous write. Identical to WRITE, but passes down
                 the hint that someone will be waiting on this IO
                 shortly.
    WRITE_FLUSH: Like WRITE_SYNC but with preceding cache flush.
    WRITE_FUA:   Like WRITE_SYNC but data is guaranteed to be on
                 non-volatile media on completion.

In other words, SYNC does not *mean* that the write must be on stable storage
on completion. It just means that someone is waiting on us to complete the
write request. Thus triggering a ZIL commit for each SYNC write request on a
ZVOL is unnecessary and harmful for performance. To make matters worse, ZVOL
users have no way to express that they actually want data to be written to
stable storage, which means the ZIL is broken for ZVOLs.

The request for stable storage is expressed by the FUA flag, so we must
commit the ZIL after the write if the FUA flag is set. In addition, we must
commit the ZIL before the write if the FLUSH flag is set.

Also, we must inform the block layer that we actually support FLUSH and FUA.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2012-02-07 16:23:06 -08:00
Brian Behlendorf 47621f3d76 Linux 3.3 compat, sops->show_options()
The second argument of sops->show_options() was changed from a
'struct vfsmount *' to a 'struct dentry *'.  Add an autoconf check
to detect the API change and then conditionally define the expected
interface.  In either case we are only interested in the zfs_sb_t.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #549
2012-02-03 10:02:01 -08:00
Brian Behlendorf b40a77aefc Add the release component to headers
When the original build system code was added the release
component was accidentally omited from the development header
install path.  This patch adds the missing path component so
it's always clear exactly what release your compiling against.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2012-01-18 12:19:47 -08:00
Brian Behlendorf ab26409db7 Linux 3.1 compat, super_block->s_shrink
The Linux 3.1 kernel has introduced the concept of per-filesystem
shrinkers which are directly assoicated with a super block.  Prior
to this change there was one shared global shrinker.

The zfs code relied on being able to call the global shrinker when
the arc_meta_limit was exceeded.  This would cause the VFS to drop
references on a fraction of the dentries in the dcache.  The ARC
could then safely reclaim the memory used by these entries and
honor the arc_meta_limit.  Unfortunately, when per-filesystem
shrinkers were added the old interfaces were made unavailable.

This change adds support to use the new per-filesystem shrinker
interface so we can continue to honor the arc_meta_limit.  The
major benefit of the new interface is that we can now target
only the zfs filesystem for dentry and inode pruning.  Thus we
can minimize any impact on the caching of other filesystems.

In the context of making this change several other important
issues related to managing the ARC were addressed, they include:

* The dnlc_reduce_cache() function which was called by the ARC
to drop dentries for the Posix layer was replaced with a generic
zfs_prune_t callback.  The ZPL layer now registers a callback to
drop these dentries removing a layering violation which dates
back to the Solaris code.  This callback can also be used by
other ARC consumers such as Lustre.

  arc_add_prune_callback()
  arc_remove_prune_callback()

* The arc_reduce_dnlc_percent module option has been changed to
arc_meta_prune for clarity.  The dnlc functions are specific to
Solaris's VFS and have already been largely eliminated already.
The replacement tunable now represents the number of bytes the
prune callback will request when invoked.

* Less aggressively invoke the prune callback.  We used to call
this whenever we exceeded the arc_meta_limit however that's not
strictly correct since it results in over zeleous reclaim of
dentries and inodes.  It is now only called once the arc_meta_limit
is exceeded and every effort has been made to evict other data from
the ARC cache.

* More promptly manage exceeding the arc_meta_limit.  When reading
meta data in to the cache if a buffer was unable to be recycled
notify the arc_reclaim thread to invoke the required prune.

* Added arcstat_prune kstat which is incremented when the ARC
is forced to request that a consumer prune its cache.  Remember
this will only occur when the ARC has no other choice.  If it
can evict buffers safely without invoking the prune callback
it will.

* This change is also expected to resolve the unexpect collapses
of the ARC cache.  This would occur because when exceeded just the
arc_meta_limit reclaim presure would be excerted on the arc_c
value via arc_shrink().  This effectively shrunk the entire cache
when really we just needed to reclaim meta data.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #466
Closes #292
2012-01-11 11:46:02 -08:00
Darik Horn 28eb9213d8 Linux 3.2 compat: set_nlink()
Directly changing inode->i_nlink is deprecated in Linux 3.2 by commit

  SHA: bfe8684869601dacfcb2cd69ef8cfd9045f62170

Use the new set_nlink() kernel function instead.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes: #462
2011-12-16 20:02:52 -08:00
Prakash Surya 6ba3b44614 Add make rule for building Arch Linux packages
Added the necessary build infrastructure for building packages
compatible with the Arch Linux distribution. As such, one can now run:

    $ ./configure
    $ make pkg     # Alternatively, one can run 'make arch' as well

on the Arch Linux machine to create two binary packages compatible with
the pacman package manager, one for the zfs userland utilities and
another for the zfs kernel modules. The new packages can then be
installed by running:

    # pacman -U $package.pkg.tar.xz

In addition, source-only packages suitable for an Arch Linux chroot
environment or remote builder can also be build using the 'sarch' make
rule.

NOTE: Since the source dist tarball is created on the fly from the head
of the build tree, it's MD5 hash signature will be continually influx.
As a result, the md5sum variable was intentionally omitted from the
PKGBUILD files, and the '--skipinteg' makepkg option is used. This may
or may not have any serious security implications, as the source tarball
is not being downloaded from an outside source.

Signed-off-by: Prakash Surya <surya1@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #491
2011-12-14 19:14:23 -08:00
Brian Behlendorf 5547c2f1bf Simplify BDI integration
Update the code to use the bdi_setup_and_register() helper to
simplify the bdi integration code.  The updated code now just
registers the bdi during mount and destroys it during unmount.

The only complication is that for 2.6.32 - 2.6.33 kernels the
helper wasn't available so in these cases the zfs code must
provide it.  Luckily the bdi_setup_and_register() function
is trivial.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #367
2011-11-08 10:19:03 -08:00
Brian Behlendorf de0a1c099b Autogen refresh for udev changes
Run autogen.sh using the same autotools versions as upstream:

 * autoconf-2.63
 * automake-1.11.1
 * libtool-2.2.6b
2011-08-08 16:30:27 -07:00
Brian Behlendorf 76659dc110 Add backing_device_info per-filesystem
For a long time now the kernel has been moving away from using the
pdflush daemon to write 'old' dirty pages to disk.  The primary reason
for this is because the pdflush daemon is single threaded and can be
a limiting factor for performance.  Since pdflush sequentially walks
the dirty inode list for each super block any delay in processing can
slow down dirty page writeback for all filesystems.

The replacement for pdflush is called bdi (backing device info).  The
bdi system involves creating a per-filesystem control structure each
with its own private sets of queues to manage writeback.  The advantage
is greater parallelism which improves performance and prevents a single
filesystem from slowing writeback to the others.

For a long time both systems co-existed in the kernel so it wasn't
strictly required to implement the bdi scheme.  However, as of
Linux 2.6.36 kernels the pdflush functionality has been retired.

Since ZFS already bypasses the page cache for most I/O this is only
an issue for mmap(2) writes which must go through the page cache.
Even then adding this missing support for newer kernels was overlooked
because there are other mechanisms which can trigger writeback.

However, there is one critical case where not implementing the bdi
functionality can cause problems.  If an application handles a page
fault it can enter the balance_dirty_pages() callpath.  This will
result in the application hanging until the number of dirty pages in
the system drops below the dirty ratio.

Without a registered backing_device_info for the filesystem the
dirty pages will not get written out.  Thus the application will hang.
As mentioned above this was less of an issue with older kernels because
pdflush would eventually write out the dirty pages.

This change adds a backing_device_info structure to the zfs_sb_t
which is already allocated per-super block.  It is then registered
when the filesystem mounted and unregistered on unmount.  It will
not be registered for mounted snapshots which are read-only.  This
change will result in flush-<pool> thread being dynamically created
and destroyed per-mounted filesystem for writeback.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #174
2011-08-04 13:37:38 -07:00
Kyle Fuller 615ab66d18 Provide a rc.d script for archlinux
Unlike most other Linux distributions archlinux installs its
init scripts in /etc/rc.d insead of /etc/init.d.  This commit
provides an archlinux rc.d script for zfs and extends the
build infrastructure to ensure it get's installed in the
correct place.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #322
2011-07-11 14:12:23 -07:00
Brian Behlendorf 2cf7f52bc4 Linux compat 2.6.39: mount_nodev()
The .get_sb callback has been replaced by a .mount callback
in the file_system_type structure.  When using the new
interface the caller must now use the mount_nodev() helper.

Unfortunately, the new interface no longer passes the vfsmount
down to the zfs layers.  This poses a problem for the existing
implementation because we currently save this pointer in the
super block for latter use.  It provides our only entry point
in to the namespace layer for manipulating certain mount options.

This needed to be done originally to allow commands like
'zfs set atime=off tank' to work properly.  It also allowed me
to keep more of the original Solaris code unmodified.  Under
Solaris there is a 1-to-1 mapping between a mount point and a
file system so this is a fairly natural thing to do.  However,
under Linux they many be multiple entries in the namespace
which reference the same filesystem.  Thus keeping a back
reference from the filesystem to the namespace is complicated.

Rather than introduce some ugly hack to get the vfsmount and
continue as before.  I'm leveraging this API change to update
the ZFS code to do things in a more natural way for Linux.
This has the upside that is resolves the compatibility issue
for the long term and fixes several other minor bugs which
have been reported.

This commit updates the code to remove this vfsmount back
reference entirely.  All modifications to filesystem mount
options are now passed in to the kernel via a '-o remount'.
This is the expected Linux mechanism and allows the namespace
to properly handle any options which apply to it before passing
them on to the file system itself.

Aside from fixing the compatibility issue, removing the
vfsmount has had the benefit of simplifying the code.  This
change which fairly involved has turned out nicely.

Closes #246
Closes #217
Closes #187
Closes #248
Closes #231
2011-07-01 13:36:39 -07:00
Brian Behlendorf 5c03efc379 Linux compat 2.6.39: security_inode_init_security()
The security_inode_init_security() function now takes an additional
qstr argument which must be passed in from the dentry if available.
Passing a NULL is safe when no qstr is available the relevant
security checks will just be skipped.

Closes #246
Closes #217
Closes #187
2011-07-01 12:40:08 -07:00
Prasad Joshi b312979252 Tear down and flush the mmap region
The inode eviction should unmap the pages associated with the inode.
These pages should also be flushed to disk to avoid the data loss.
Therefore, use truncate_setsize() in evict_inode() to release the
pagecache.

The API truncate_setsize() was added in 2.6.35 kernel. To ensure
compatibility with the old kernel, the patch defines its own
truncate_setsize function.

Signed-off-by: Prasad Joshi <pjoshi@stec-inc.com>
Closes #255
2011-06-27 09:59:19 -07:00
Brian Behlendorf 2e08aedba4 Always check -Wno-unused-but-set-variable gcc support
The previous commit 8a7e1ceefa wasn't
quite right.  This check applies to both the user and kernel space
build and as such we must make sure it runs regardless of what
the --with-config option is set too.

For example, if --with-config=kernel then the autoconf test does
not run and we generate build warnings when compiling the kernel
packages.
2011-06-14 16:40:35 -07:00
Brian Behlendorf 8a7e1ceefa Check for -Wno-unused-but-set-variable gcc support
Gcc versions 4.3.2 and earlier do not support the compiler flag
-Wno-unused-but-set-variable.  This can lead to build failures
on older Linux platforms such as Debian Lenny.  Since this is
an optional build argument this changes add a new autoconf check
for the option.  If it is supported by the installed version of
gcc then it is used otherwise it is omited.

See commit's 12c1acde76 and
79713039a2 for the reason the
-Wno-unused-but-set-variable options was originally added.
2011-06-14 14:43:22 -07:00
Brian Behlendorf df554c148e Fix 'zfs set volsize=N pool/dataset'
This change fixes a kernel panic which would occur when resizing
a dataset which was not open.  The objset_t stored in the
zvol_state_t will be set to NULL when the block device is closed.
To avoid this issue we pass the correct objset_t as the third arg.

The code has also been updated to correctly notify the kernel
when the block device capacity changes.  For 2.6.28 and newer
kernels the capacity change will be immediately detected.  For
earlier kernels the capacity change will be detected when the
device is next opened.  This is a known limitation of older
kernels.

Online ext3 resize test case passes on 2.6.28+ kernels:
$ dd if=/dev/zero of=/tmp/zvol bs=1M count=1 seek=1023
$ zpool create tank /tmp/zvol
$ zfs create -V 500M tank/zd0
$ mkfs.ext3 /dev/zd0
$ mkdir /mnt/zd0
$ mount /dev/zd0 /mnt/zd0
$ df -h /mnt/zd0
$ zfs set volsize=800M tank/zd0
$ resize2fs /dev/zd0
$ df -h /mnt/zd0

Original-patch-by: Fajar A. Nugraha <github@fajar.net>
Closes #68
Closes #84
2011-05-02 08:54:40 -07:00
Gunnar Beutner 055656d4f4 Implemented NFS export_operations.
Implemented the required NFS operations for exporting ZFS datasets
using the in-kernel NFS daemon.
2011-04-29 12:36:13 -07:00
Brian Behlendorf bdf4328b04 Linux 2.6.28 compat, insert_inode_locked()
Added insert_inode_locked() helper function, prior to this most callers
used insert_inode_hash().  The older method doesn't check for collisions
in the inode_hashtable but it still acceptible for use.  Fallback to
using insert_inode_hash() when insert_inode_locked() is unavailable.
2011-03-22 12:15:54 -07:00
Brian Behlendorf 01c0e61da0 Add init scripts
To support automatically mounting your zfs on filesystem on boot
a basic init script is needed.  Unfortunately, every distribution
has their own idea of the _right_ way to do things.  Rather than
write one very complicated portable init script, which would be
invariably replaced by the distributions own anyway.  I have
instead added support to provide multiple distribution specific
init scripts.

The correct init script for your distribution will be selected
by ZFS_AC_DEFAULT_PACKAGE which will set DEFAULT_INIT_SCRIPT.
During 'make install' the correct script for your system will
be installed from zfs/etc/init.d/zfs.DEFAULT_INIT_SCRIPT to the
usual /etc/init.d/zfs location.

Currently, there is zfs.fedora and a more generic zfs.lsb init
script.  Hopefully, the distribution maintainers who know best
how they want their init scripts to function will feedback their
approved versions to be included in the project.

This change does not consider upstart jobs but I'm not at all
opposed to add that sort of thing.
2011-03-17 16:51:54 -07:00
Brian Behlendorf 45066d1f20 Linux 2.6.38 compat, blkdev_get_by_path()
The open_bdev_exclusive() function has been replaced (again) by the
more generic blkdev_get_by_path() function.  Additionally, the
counterpart function close_bdev_exclusive() has been replaced by
blkdev_put().  Because these functions are more generic versions
of the functions they replaced the compatibility macro must add
the FMODE_EXCL mask to ensure they are exclusive.

Closes #114
2011-02-23 12:29:38 -08:00
Brian Behlendorf 2c395def27 Linux 2.6.36 compat, sops->evict_inode()
The new prefered inteface for evicting an inode from the inode cache
is the ->evict_inode() callback.  It replaces both the ->delete_inode()
and ->clear_inode() callbacks which were previously used for this.
2011-02-11 13:47:51 -08:00