Commit Graph

51 Commits

Author SHA1 Message Date
Brian Behlendorf
ee93035378 Use sb->s_d_op default dentry operations
As of Linux 2.6.37 the right way to register custom dentry
operations is to use the super block's ->s_d_op field.
For older kernels they should be registered as part of the
lookup operation.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #1223
2013-01-18 15:04:23 -08:00
Brian Behlendorf
7973e464de Revert "Revert "Fix unlink/xattr deadlock""
This reverts commit 53c7411919
effectively reinstating the asynchronous xattr cleanup code.

These Linux changes were reverted because after testing
and careful contemplation I was convinced that due to the
89260a1c8851ce05ea04b23606ba438b271d890 commit they were no
longer required.

Unfortunately, the deadlock described in #1176  was a case
which wasn't considered.  At mount zfs_unlinked_drain() can
occur which will unlink a list of znodes in effectively a
random order which isn't safe.  The only reason it was safe
to originally revert this change was the we could guarantee
that the VFS would always prune the xattr leaves before the
parents.

Therefore, until we can cleanly resolve this deadlock for
all cases we need to keep this change in spite of the xattr
unlink performance penalty associated with it.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #1176
Issue #457
2013-01-17 11:24:20 -08:00
Brian Behlendorf
7b3e34ba5a Fix 'zfs rollback' on mounted file systems
Rolling back a mounted filesystem with open file handles and
cached dentries+inodes never worked properly in ZoL.  The
major issue was that Linux provides no easy mechanism for
modules to invalidate the inode cache for a file system.

Because of this it was possible that an inode from the previous
filesystem would not get properly dropped from the cache during
rolling back.  Then a new inode with the same inode number would
be create and collide with the existing cached inode.  Ideally
this would trigger an VERIFY() but in practice the error wasn't
handled and it would just NULL reference.

Luckily, this issue can be resolved by sprucing up the existing
Solaris zfs_rezget() functionality for the Linux VFS.

The way it works now is that when a file system is rolled back
all the cached inodes will be traversed and refetched from disk.
If a version of the cached inode exists on disk the in-core
copy will be updated accordingly.  If there is no match for that
object on disk it will be unhashed from the inode cache and
marked as stale.

This will effectively make the inode unfindable for lookups
allowing the inode number to be immediately recycled.  The inode
will then only be accessible from the cached dentries.  Subsequent
dentry lookups which reference a stale inode will result in the
dentry being invalidated.  Once invalidated the dentry will drop
its reference on the inode allowing it to be safely pruned from
the cache.

Special care is taken for negative dentries since they do not
reference any inode.  These dentires will be invalidate based
on when they were added to the dentry cache.  Entries added
before the last rollback will be invalidate to prevent them
from masking real files in the dataset.

Two nice side effects of this fix are:

* Removes the dependency on spl_invalidate_inodes(), it can now
  be safely removed from the SPL when we choose to do so.

* zfs_znode_alloc() no longer requires a dentry to be passed.
  This effectively reverts this portition of the code to its
  upstream counterpart.  The dentry is not instantiated more
  correctly in the Linux ZPL layer.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ned Bass <bass6@llnl.gov>
Closes #795
2013-01-17 09:51:20 -08:00
Matthew Ahrens
a94addd974 Illumos #3208 cross-endian incorrect user/group accounting
3208 moving zpool cross-endian results in incorrect user/group
accounting

Reviewed by: Adam Leventhal <ahl@delphix.com>
Reviewed by: Christopher Siden <chris.siden@delphix.com>
Approved by: Richard Lowe <richlowe@richlowe.net>

References:
  illumos/illumos-gate@e828a46d29
  illumos changeset: 13835:eea81edc4f14
  https://www.illumos.org/issues/3208

Ported-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #627
Closes #1136
2013-01-14 09:32:22 -08:00
Brian Behlendorf
53c7411919 Revert "Fix unlink/xattr deadlock"
This reverts commit b00131d43c which
is no longer needed due to e89260a1c8.

This change forces all xattr znodes to hold a reference on their
parent which ensures prune_icache() will never attempt to evict
both the parent and child concurrently.  This effectively prevents
the deadlock condition from ever occuring.

Therefore we can safely revert back to the upstream synchronous
cleanup code.  This is nice because it keeps our code base closer
to upstream and resolves the performance issues introduced by the
original deadlock fix.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #457
2012-12-05 13:41:30 -08:00
Matthew Ahrens
04434775b7 Illumos #3100: zvol rename fails with EBUSY when dirty.
illumos/illumos-gate@2e2c135528
Illumos changeset: 13780:6da32a929222

3100 zvol rename fails with EBUSY when dirty

Reviewed by: Christopher Siden <chris.siden@delphix.com>
Reviewed by: Adam H. Leventhal <ahl@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Garrett D'Amore <garrett@damore.org>
Approved by: Eric Schrock <eric.schrock@delphix.com>

Ported-by: Etienne Dechamps <etienne.dechamps@ovh.net>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #995
2012-10-03 13:59:02 -07:00
Cyril Plisko
04f9432d3b Make ZFS filesystem id persistent across different machines
Use ZFS dataset fsid guid as a unique file system id, similar to what is
done on Illumos/OpenSolaris.

Signed-off-by: Cyril Plisko <cyril.plisko@mountall.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #888
2012-09-06 12:47:11 -07:00
Brian Behlendorf
bafc4e9e2a Suppress 'zfs_sb_create' memory warning
When mutex debugging is enabled in your kernel the increased
size of the mutex structures can push the zfs_sb_t type beyond
the 8k warning threshold.  This isn't harmful so we suppress
the warning for this case.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #628
2012-08-10 16:43:32 -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
Gunnar Beutner
1f0d8a566f Fixed a NULL pointer dereference bug in zfs_preumount
When zpl_fill_super -> zfs_domount fails (e.g. because the dataset
was destroyed before it could be successfully mounted) the subsequent
call to zpl_kill_sb -> zfs_preumount would derefence a NULL pointer.

This bug can be reproduced using this shell script:

 #!/bin/sh
 (
 while true; do
 	zfs create -o mountpoint=legacz tank/bar
 	zfs destroy tank/bar
 done
 ) &

 (
 while true; do
 	mount -t zfs tank/bar /mnt
 	umount /mnt
 done
 ) &

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #639
2012-04-05 11:29:42 -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
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
Brian Behlendorf
82a37189aa Implement SA based xattrs
The current ZFS implementation stores xattrs on disk using a hidden
directory.  In this directory a file name represents the xattr name
and the file contexts are the xattr binary data.  This approach is
very flexible and allows for arbitrarily large xattrs.  However,
it also suffers from a significant performance penalty.  Accessing
a single xattr can requires up to three disk seeks.

  1) Lookup the dnode object.
  2) Lookup the dnodes's xattr directory object.
  3) Lookup the xattr object in the directory.

To avoid this performance penalty Linux filesystems such as ext3
and xfs try to store the xattr as part of the inode on disk.  When
the xattr is to large to store in the inode then a single external
block is allocated for them.  In practice most xattrs are small
and this approach works well.

The addition of System Attributes (SA) to zfs provides us a clean
way to make this optimization.  When the dataset property 'xattr=sa'
is set then xattrs will be preferentially stored as System Attributes.
This allows tiny xattrs (~100 bytes) to be stored with the dnode and
up to 64k of xattrs to be stored in the spill block.  If additional
xattr space is required, which is unlikely under Linux, they will be
stored using the traditional directory approach.

This optimization results in roughly a 3x performance improvement
when accessing xattrs which brings zfs roughly to parity with ext4
and xfs (see table below).  When multiple xattrs are stored per-file
the performance improvements are even greater because all of the
xattrs stored in the spill block will be cached.

However, by default SA based xattrs are disabled in the Linux port
to maximize compatibility with other implementations.  If you do
enable SA based xattrs then they will not be visible on platforms
which do not support this feature.

----------------------------------------------------------------------
   Time in seconds to get/set one xattr of N bytes on 100,000 files
------+--------------------------------+------------------------------
      |            setxattr            |            getxattr
bytes |  ext4     xfs zfs-dir  zfs-sa  |  ext4     xfs zfs-dir  zfs-sa
------+--------------------------------+------------------------------
1     |  2.33   31.88   21.50    4.57  |  2.35    2.64    6.29    2.43
32    |  2.79   30.68   21.98    4.60  |  2.44    2.59    6.78    2.48
256   |  3.25   31.99   21.36    5.92  |  2.32    2.71    6.22    3.14
1024  |  3.30   32.61   22.83    8.45  |  2.40    2.79    6.24    3.27
4096  |  3.57  317.46   22.52   10.73  |  2.78   28.62    6.90    3.94
16384 |   n/a 2342.39   34.30   19.20  |   n/a   45.44  145.90    7.55
65536 |   n/a 2941.39  128.15  131.32* |   n/a  141.92  256.85  262.12*

Legend:
* ext4      - Stock RHEL6.1 ext4 mounted with '-o user_xattr'.
* xfs       - Stock RHEL6.1 xfs mounted with default options.
* zfs-dir   - Directory based xattrs only.
* zfs-sa    - Prefer SAs but spill in to directories as needed, a
              trailing * indicates overflow in to directories occured.

NOTE: Ext4 supports 4096 bytes of xattr name/value pairs per file.
NOTE: XFS and ZFS have no limit on xattr name/value pairs per file.
NOTE: Linux limits individual name/value pairs to 65536 bytes.
NOTE: All setattr/getattr's were done after dropping the cache.
NOTE: All tests were run against a single hard drive.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #443
2011-11-28 15:45:51 -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
591fb62f19 Disown dataset in zfs_sb_create()
Fix an unlikely failure cause in zfs_sb_create() which could
leave the dataset owned on error and thus unavailable until
after a reboot.  Disown the dataset if SA are expected but
are in fact missing.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2011-11-08 10:18:40 -08:00
Brian Behlendorf
86f35f34f4 Export symbols for the VFS API
Export all symbols already marked extern in the zfs_vfsops.h
header.  Several non-static symbols have also been added to
the header and exportewd.  This allows external modules to
more easily create and manipulate properly created ZFS
filesystem type datasets.

Rename zfsvfs_teardown() to zfs_sb_teardown and export it.
This is done simply for consistency with the rest of the code
base.  All other zfsvfs_* functions have already been renamed.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2011-10-11 10:25:59 -07:00
Andreas Dilger
baab063016 zpl: Fix "df -i" to have better free inodes value
Due to the confusion in Linux statfs between f_frsize and f_bsize
the blocks counts were changed to be in units of z_max_blksize
instead of SPA_MINBLOCKSIZE as it is on other platforms.

However, the free files calculation in zfs_statvfs() is limited by
the free blocks count, since each dnode consumes one block/sector.
This provided a reasonable estimate of free inodes, but on Linux
this meant that the free inodes count was underestimated by a large
amount, since 256 512-byte dnodes can fit into a 128kB block, and
more if the max blocksize is increased to 1MB or larger.

Also, the use of SPA_MINBLOCKSIZE is semantically incorrect since
DNODE_SIZE may change to a value other than SPA_MINBLOCKSIZE and
may even change per dataset, and devices with large sectors setting
ashift will also use a larger blocksize.

Correct the f_ffree calculation to use (availbytes >> DNODE_SHIFT)
to more accurately compute the maximum number of dnodes that can
be created.

Signed-off-by: Andreas Dilger <adilger@whamcloud.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #413
Closes #400
2011-09-28 11:27:10 -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
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
Gunnar Beutner
b00131d43c Fix unlink/xattr deadlock
The problem here is that prune_icache() tries to evict/delete
both the xattr directory inode as well as at least one xattr
inode contained in that directory. Here's what happens:

1. File is created.
2. xattr is created for that file (behind the scenes a xattr
   directory and a file in that xattr directory are created)
3. File is deleted.
4. Both the xattr directory inode and at least one xattr
   inode from that directory are evicted by prune_icache();
   prune_icache() acquires a lock on both inodes before it
   calls ->evict() on the inodes

When the xattr directory inode is evicted zfs_zinactive attempts
to delete the xattr files contained in that directory. While
enumerating these files zfs_zget() is called to obtain a reference
to the xattr file znode - which tries to lock the xattr inode.
However that very same xattr inode was already locked by
prune_icache() further up the call stack, thus leading to a
deadlock.

This can be reliably reproduced like this:
$ touch test
$ attr -s a -V b test
$ rm test
$ echo 3 > /proc/sys/vm/drop_caches

This patch fixes the deadlock by moving the zfs_purgedir() call to
zfs_unlinked_drain().  Instead zfs_rmnode() now checks whether the
xattr dir is empty and leaves the xattr dir in the unlinked set if
it finds any xattrs.

To ensure zfs_unlinked_drain() never accesses a stale super block
zfsvfs_teardown() has been update to block until the iput taskq
has been drained.  This avoids a potential race where a file with
an xattr directory is removed and the file system is immediately
unmounted.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #266
2011-06-20 13:47:03 -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
e30c0ada6d Linux 2.6.39 compat, invalidate_inodes()
Update code to use the spl_invalidate_inodes() wrapper.  This hides
some of the complexity of determining if invalidate_inodes() was
exported, and if so what is its prototype.  The second argument
of spl_invalidate_inodes() determined the behavior of how dirty
inodes are handled.  By passing a zero we are indicated that we
want those inodes to be treated as busy and skipped.
2011-04-19 08:57:23 -07:00
Brian Behlendorf
0de19dad9c Register .remount_fs handler
Register the missing .remount_fs handler.  This handler isn't strictly
required because the VFS does a pretty good job updating most of the
MS_* flags.  However, there's no harm in using the hook to call the
registered zpl callback for various MS_* flags.  Additionaly, this
allows us to lay the ground work for more complicated argument parsing
in the future.
2011-03-15 13:33:29 -07:00
Brian Behlendorf
03f9ba9d99 Register .sync_fs handler
Register the missing .sync_fs handler.  This is a noop in most cases
because the usual requirement is that sync just be initiated.  As part
of the DMU's normal transaction processing txgs will be frequently
synced.  However, when the 'wait' flag is set the requirement is that
.sync_fs must not return until the data is safe on disk.  With the
addition of the .sync_fs handler this is now properly implemented.
2011-03-15 13:33:29 -07:00
Brian Behlendorf
53cf50e081 Set stat->st_dev and statfs->f_fsid
Filesystems like ZFS must use what the kernel calls an anonymous super
block.  Basically, this is just a filesystem which is not backed by a
single block device.  Normally this block device's dev_t is stored in
the super block.  For anonymous super blocks a unique reserved dev_t
is assigned as part of get_sb().

This sb->s_dev must then be set in the returned stat structures as
stat->st_dev.  This allows userspace utilities to easily detect the
boundries of a specific filesystem.  Tools such as 'du' depend on this
for proper accounting.

Additionally, under OpenSolaris the statfs->f_fsid is set to the device
id.  To preserve consistency with OpenSolaris we also set the fsid to
the device id.  Other Linux filesystem (ext) set the fsid to a unique
value determined by the filesystems uuid.  This value is unique but
maintains no relationship to the device id.  This may be desirable
when exporting NFS filesystem because it minimizes to chance of a
client observing the same fsid from two different servers.

Closes #140
2011-03-07 16:06:22 -08:00
Brian Behlendorf
05ff35c602 Increase fragment size to block size
The underlying storage pool actually uses multiple block
size.  Under Solaris frsize (fragment size) is reported as
the smallest block size we support, and bsize (block size)
as the filesystem's maximum block size.  Unfortunately,
under Linux the fragment size and block size are often used
interchangeably.  Thus we are forced to report both of them
as the filesystem's maximum block size.

Closes #112
2011-02-23 14:00:06 -08:00
Brian Behlendorf
ceb43b935d Invalidate dcache and inode cache
When performing a 'zfs rollback' it's critical to invalidate
the previous dcache and inode cache.  If we don't there will
stale cache entries which when accessed will result in EIOs.
2011-02-10 09:27:22 -08:00
Brian Behlendorf
3558fd73b5 Prototype/structure update for Linux
I appologize in advance why to many things ended up in this commit.
When it could be seperated in to a whole series of commits teasing
that all apart now would take considerable time and I'm not sure
there's much merrit in it.  As such I'll just summerize the intent
of the changes which are all (or partly) in this commit.  Broadly
the intent is to remove as much Solaris specific code as possible
and replace it with native Linux equivilants.  More specifically:

1) Replace all instances of zfsvfs_t with zfs_sb_t.  While the
type is largely the same calling it private super block data
rather than a zfsvfs is more consistent with how Linux names
this.  While non critical it makes the code easier to read when
your thinking in Linux friendly VFS terms.

2) Replace vnode_t with struct inode.  The Linux VFS doesn't have
the notion of a vnode and there's absolutely no good reason to
create one.  There are in fact several good reasons to remove it.
It just adds overhead on Linux if we were to manage one, it
conplicates the code, and it likely will lead to bugs so there's
a good change it will be out of date.  The code has been updated
to remove all need for this type.

3) Replace all vtype_t's with umode types.  Along with this shift
all uses of types to mode bits.  The Solaris code would pass a
vtype which is redundant with the Linux mode.  Just update all the
code to use the Linux mode macros and remove this redundancy.

4) Remove using of vn_* helpers and replace where needed with
inode helpers.  The big example here is creating iput_aync to
replace vn_rele_async.  Other vn helpers will be addressed as
needed but they should be be emulated.  They are a Solaris VFS'ism
and should simply be replaced with Linux equivilants.

5) Update znode alloc/free code.  Under Linux it's common to
embed the inode specific data with the inode itself.  This removes
the need for an extra memory allocation.  In zfs this information
is called a znode and it now embeds the inode with it.  Allocators
have been updated accordingly.

6) Minimal integration with the vfs flags for setting up the
super block and handling mount options has been added this
code will need to be refined but functionally it's all there.

This will be the first and last of these to large to review commits.
2011-02-10 09:27:21 -08:00
Brian Behlendorf
bcf308227c Remove zfs_ctldir.[ch]
This code is used for snapshot and heavily leverages Solaris
functionality we do not want to reimplement.  These files have
been removed, including references to them, and will be replaced
by a zfs_snap.c/zpl_snap.c implementation which handles snapshots.
2011-02-10 09:27:21 -08:00
Brian Behlendorf
b516a07b99 Disable fuid features
These features should probably be enabled in the Linux zpl code.
For now I'm disabling them until it's clear what needs to be done.
2011-02-10 09:27:20 -08:00
Brian Behlendorf
d5e53f9d06 Disable zfs_sync during oops/panic
Minor update to ensure zfs_sync() is disabled if a kernel oops/panic
is triggered.  As the comment says 'data integrity is job one'.  This
change could have been done by defining panicstr to oops_in_progress
in the SPL.  But I felt it was better to use the native Linux API
here since to be clear.
2011-02-10 09:27:20 -08:00
Brian Behlendorf
acb5376940 Disable Shutdown/Reboot
This support has been disable with HAVE_SHUTDOWN.  We can support
this at some point by adding the needed reboot notifiers.
2011-02-10 09:27:20 -08:00
Brian Behlendorf
cb28b3494e Remove SYNC_ATTR check
This flag does not need to be support under Linux.  As the comment
says it was only there to support fsflush() for old filesystem like
UFS.  This is not needed under Linux.
2011-02-10 09:27:20 -08:00
Brian Behlendorf
e15c023014 Remove mount options
Mount option parsing is still very Linux specific and will be
handled above this zfs filesystem layer.  Honoring those mount
options once set if of course the responsibility of the lower
layers.
2011-02-10 09:27:20 -08:00
Brian Behlendorf
d7cafa8e3e Remove zfs_active_fs_count
This variable was used to ensure that the ZFS module is never
removed while the filesystem is mounted.  Once again the generic
Linux VFS handles this case for us so it can be removed.
2011-02-10 09:27:20 -08:00
Brian Behlendorf
42ab36aa36 Remove unused mount functions
The functions zfs_mount_label_policy(), zfs_mountroot(), zfs_mount()
will not be needed because most of what they do is already handled
by the generic Linux VFS layer.  They all call zfs_domount() which
creates the actual dataset, the caller of this library call which
will be in the zpl layer is responsible for what's left.
2011-02-10 09:27:20 -08:00
Brian Behlendorf
c0b3dc7d07 Remove zfs_major/zfs_minor/zfsfstype
Under Linux we don't need to reserve a major or minor number for
the filesystem.  We can rely on the VFS to handle colisions without
this being handled by the lower ZFS layers.

Additionally, there is no need to keep a zfsfstype around.  We are
not limited on Linux by the OpenSolaris infrastructure which needed
this.  The upper zpl layer can specify the filesystem type.
2011-02-10 09:27:20 -08:00
Brian Behlendorf
4b3f12ecd5 Remove Solaris VFS Hooks
The ZFS code is being restructured to act as a library and a stand
alone module.  This allows us to leverage most of the existing code
with minimal modification.  It also means we need to drop the Solaris
vfs/vnode functions they will be replaced by Linux equivilants and
updated to be Linux friendly.
2011-02-10 09:27:20 -08:00
Brian Behlendorf
960e08fe3e VFS: Add zfs_inode_update() helper
For the moment we have left ZFS unchanged and it updates many values
as part of the znode.  However, some of these values should be set
in the inode.  For the moment this is handled by adding a function
called zfs_inode_update() which updates the inode based on the znode.

This is considered a workaround until we can systematically go
through the ZFS code and have it directly update the inode.  At
which point zfs_update_inode() can be dropped entirely.  Keeping
two copies of the same data isn't only inefficient it's a breeding
ground for bugs.
2011-02-10 09:27:20 -08:00
Brian Behlendorf
4e1b54fdde Remove zfs_parse_bootfs() support
Remove unneeded bootfs functions.  This support shouldn't be required
for the Linux port, and even if it is it would need to be reworked
to integrate cleanly with Linux.
2011-02-10 09:21:43 -08:00
Brian Behlendorf
bc3e15e386 Wrap with HAVE_MLSLABEL
The zfs_check_global_label() function is part of the HAVE_MLSLABEL
support which was previously commented out by a HAVE_ZPL check.
Since we're still deciding what to do about mls labels wrap it
with the preexisting macro to keep it compiled out.
2011-02-10 09:21:42 -08:00
Brian Behlendorf
e5c39b95a7 Export required vfs/vn symbols 2011-02-10 09:21:42 -08:00
Brian Behlendorf
149e873ab1 Fix minor compiler warnings
These compiler warnings were introduced when code which was
previously #ifdef'ed out by HAVE_ZPL was re-added for use
by the posix layer.  All of the following changes should be
obviously correct and will cause no semantic changes.
2011-01-06 15:04:28 -08:00
Ricardo M. Correia
0151834d65 Register the space accounting callback even when we don't have the ZPL.
This callback is needed for properly accounting the per-uid and per-gid
space usage.  Even if we don't have the ZPL, we still need this callback
in order to have proper on-disk ZPL compatibility and to be able to use
Lustre quotas.

Fortunately, the callback doesn't have any ZPL/VFS dependencies so we
can just move it out of #ifdef HAVE_ZPL.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2010-10-04 11:34:39 -07:00
Brian Behlendorf
60101509ee Add linux kernel disk support
Native Linux vdev disk interfaces

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2010-08-31 13:41:57 -07:00
Brian Behlendorf
572e285762 Update to onnv_147
This is the last official OpenSolaris tag before the public
development tree was closed.
2010-08-26 14:24:34 -07:00
Brian Behlendorf
428870ff73 Update core ZFS code from build 121 to build 141. 2010-05-28 13:45:14 -07:00
Brian Behlendorf
45d1cae3b8 Rebase master to b121 2009-08-18 11:43:27 -07:00
Brian Behlendorf
9babb37438 Rebase master to b117 2009-07-02 15:44:48 -07:00
Brian Behlendorf
fb5f0bc833 Rebase master to b105 2009-01-15 13:59:39 -08:00