Commit Graph

90 Commits

Author SHA1 Message Date
Chunwei Chen 15126e5d08 Linux 4.4 compat: xattr operations takes xattr_handler
The xattr_hander->{list,get,set} were changed to take a xattr_handler,
and handler_flags argument was removed and should be accessed by
handler->flags.

Signed-off-by: Chunwei Chen <david.chen@osnexus.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #4021
2015-12-04 14:59:10 -08:00
Lukas Wunner c1013eb7ba Linux 4.3 compat: bio_end_io_t / BIO_UPTODATE
Commit torvalds/linux@4246a0b63b
("block: add a bi_error field to struct bio") dropped the error
argument from bio_endio in favor of newly introduced bio->bi_error.
This also replaces bio->bi_flags value BIO_UPTODATE.

bio_endio was a 3 argument function until Linux 2.6.24, which made it
a 2 argument function, and now the prototype has changed yet again to
a 1 argument function. Support for pre 2.6.24 kernels was already
dropped with 37f9dac592 ("zvol processing should use struct bio")
which assumed the 2 argument version in zvol_request(). Remaining code
to support the 3 argument version is hereby removed.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Issue #3799
2015-09-29 15:27:14 -07:00
Richard Yao 8198d18ca7 Reintroduce IO accounting on zvols on Linux 3.19+
zfsonlinux/zfs@e20cd6f7a8 caused us to
lose IO accounting on zvols. When I originally wrote that last year, the
symbols we needed to maintain IO accounting were GPL exported, but
torvalds/linux@394ffa503b provided
suitable symbols for restoring this functionality 4 months later.  We
can call them to restore the IO accounting on Linux 3.19 and later as
well as any older kernels where that patch is backported.

Signed-off-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #3741
2015-09-09 09:29:24 -07:00
Richard Yao 7d6e2adb4e Remove blk_rq_bytes()/blk_rq_sectors autotools checks
Signed-off-by: Richard Yao <ryao@gentoo.org>
2015-09-04 15:37:24 -04:00
Richard Yao f952eaa7ec Remove blk_rq_pos() autotools check
Signed-off-by: Richard Yao <ryao@gentoo.org>
2015-09-04 15:37:24 -04:00
Richard Yao f8c56b405d Remove blk_fetch_request() autotools check
Signed-off-by: Richard Yao <ryao@gentoo.org>
2015-09-04 15:37:24 -04:00
Richard Yao e8c6be131c Remove blk_requeue_request() autotools check
Signed-off-by: Richard Yao <ryao@gentoo.org>
2015-09-04 15:37:24 -04:00
Richard Yao dd6f9fe61b Remove blk_end_request() autotools check.
Signed-off-by: Richard Yao <ryao@gentoo.org>
2015-09-04 15:37:24 -04:00
Richard Yao 65f340e725 Remove rq_is_sync() autotools check
Signed-off-by: Richard Yao <ryao@gentoo.org>
2015-09-04 15:37:24 -04:00
Richard Yao 9ddf9b8e15 Remove rq_for_each_segment() autotools check
Signed-off-by: Richard Yao <ryao@gentoo.org>
2015-09-04 15:37:24 -04:00
Richard Yao 37f9dac592 zvol processing should use struct bio
Internally, zvols are files exposed through the block device API. This
is intended to reduce overhead when things require block devices.
However, the ZoL zvol code emulates a traditional block device in that
it has a top half and a bottom half. This is an unnecessary source of
overhead that does not exist on any other OpenZFS platform does this.
This patch removes it. Early users of this patch reported double digit
performance gains in IOPS on zvols in the range of 50% to 80%.

Comments in the code suggest that the current implementation was done to
obtain IO merging from Linux's IO elevator. However, the DMU already
does write merging while arc_read() should implicitly merge read IOs
because only 1 thread is permitted to fetch the buffer into ARC. In
addition, commercial ZFSOnLinux distributions report that regular files
are more performant than zvols under the current implementation, and the
main consumers of zvols are VMs and iSCSI targets, which have their own
elevators to merge IOs.

Some minor refactoring allows us to register zfs_request() as our
->make_request() handler in place of the generic_make_request()
function. This eliminates the layer of code that broke IO requests on
zvols into a top half and a bottom half. This has several benefits:

1. No per zvol spinlocks.
2. No redundant IO elevator processing.
3. Interrupts are disabled only when actually necessary.
4. No redispatching of IOs when all taskq threads are busy.
5. Linux's page out routines will properly block.
6. Many autotools checks become obsolete.

An unfortunate consequence of eliminating the layer that
generic_make_request() is that we no longer calls the instrumentation
hooks for block IO accounting. Those hooks are GPL-exported, so we
cannot call them ourselves and consequently, we lose the ability to do
IO monitoring via iostat.  Since zvols are internally files mapped as
block devices, this should be okay. Anyone who is willing to accept the
performance penalty for the block IO layer's accounting could use the
loop device in between the zvol and its consumer. Alternatively, perf
and ftrace likely could be used. Also, tools like latencytop will still
work. Tools such as latencytop sometimes provide a better view of
performance bottlenecks than the traditional block IO accounting tools
do.

Lastly, if direct reclaim occurs during spacemap loading and swap is on
a zvol, this code will deadlock. That deadlock could already occur with
sync=always on zvols. Given that swap on zvols is not yet production
ready, this is not a blocker.

Signed-off-by: Richard Yao <ryao@gentoo.org>
2015-09-04 15:30:24 -04:00
Richard Yao 782b2c326e VDEV_REQ_FUA should be mapped to REQ_FUA
Pre-2.6.37 kernels support REQ_FUA in request flags, but not in BIO
flags. zvols are the only consumer of VDEV_REQ_FUA and since they are
passed requests, they should be obey the REQ_FUA flag like later
kernels. This optimization will only matter on 2.6.36 and 2.6.37 because
the zvol rework changes things to use bio, where we no longer are able
to distinguish on earlier kernels

Signed-off-by: Richard Yao <ryao@gentoo.org>
2015-09-02 12:39:08 -04:00
Richard Yao 97771edaca Remove blk_queue_io_opt() autotools check
This is needed for supporting kernels earlier than 2.6.30. Support for
those kernels was dropped, so we can safely remove this check.

Signed-off-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2015-09-01 09:33:18 -07:00
Richard Yao 3c119330a6 Remove blk_queue_physical_block_size() autotools check
This is needed for supporting kernels earlier than 2.6.30. Support for
those kernels was dropped, so we can safely remove this check.

Signed-off-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2015-09-01 09:33:18 -07:00
Brian Behlendorf 278bee9319 Linux 3.18 compat: Snapshot auto-mounting
Re-factor the .zfs/snapshot auto-mouting code to take in to account
changes made to the upstream kernels.  And to lay the groundwork for
enabling access to .zfs snapshots via NFS clients.  This patch makes
the following core improvements.

* All actively auto-mounted snapshots are now tracked in two global
trees which are indexed by snapshot name and objset id respectively.
This allows for fast lookups of any auto-mounted snapshot regardless
without needing access to the parent dataset.

* Snapshot entries are added to the tree in zfsctl_snapshot_mount().
However, they are now removed from the tree in the context of the
unmount process.  This eliminates the need complicated error logic
in zfsctl_snapshot_unmount() to handle unmount failures.

* References are now taken on the snapshot entries in the tree to
ensure they always remain valid while a task is outstanding.

* The MNT_SHRINKABLE flag is set on the snapshot vfsmount_t right
after the auto-mount succeeds.  This allows to kernel to unmount
idle auto-mounted snapshots if needed removing the need for the
zfsctl_unmount_snapshots() function.

* Snapshots in active use will not be automatically unmounted.  As
long as at least one dentry is revalidated every zfs_expire_snapshot/2
seconds the auto-unmount expiration timer will be extended.

* Commit torvalds/linux@bafc9b7 caused snapshots auto-mounted by ZFS
to be immediately unmounted when the dentry was revalidated.  This
was a consequence of ZFS invaliding all snapdir dentries to ensure that
negative dentries didn't mask new snapshots.  This patch modifies the
behavior such that only negative dentries are invalidated.  This solves
the issue and may result in a performance improvement.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #3589
Closes #3344
Closes #3295
Closes #3257
Closes #3243
Closes #3030
Closes #2841
2015-08-31 13:54:39 -07:00
Chunwei Chen 17888ae30d Add compatibility layer for {kmap,kunmap}_atomic
Starting from linux-2.6.37, {kmap,kunmap}_atomic takes 1 argument instead of 2.
We use zfs_{kmap,kunmap}_atomic as wrappers and always take 2 argument, but
ignore the 2nd for newer kernel.

Signed-off-by: Chunwei Chen <tuxoko@gmail.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2015-08-24 10:13:25 -07:00
Brian Behlendorf e80da86447 Linux 4.2 compat: bdi_setup_and_register()
The vfs_compat.h header should include the linux/backing-dev.h header
because it depends on the bdi_* functions defined there.  In previous
kernels this header was being indirectly included which prevented a
build failure.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Richard Yao <ryao@gentoo.org>
Closes #3596
2015-07-17 09:15:43 -07:00
Tim Chase e48533383b Linux 2.6.36 compat, use REQ_FAILFAST_MASK and remove pre-2.6.36 support
Commit f4af6bb783 which added support
for REQ_FAILFAST_MASK but the new autoconf test didn't use the same
preprocessor macro name as the code did.

The effect is that FAILFAST mode has not been enabled for ZoL in any
post-2.6.35 kernel.

Retire the HAVE_BIO_RW_FAILFAST interface used in pre-2.6.28 kernels.

Raise an error condition if the FAILFAST interface can't be detected.

Signed-off-by: Tim Chase <tim@onlight.com
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #3386
2015-05-11 15:07:00 -07:00
Brian Behlendorf 8c45def24a Linux 4.0 compat: bdi_setup_and_register()
The 'capabilities' argument which was passed to bdi_setup_and_register()
has been removed.  File systems should no longer pass BDI_CAP_MAP_COPY.
For our purposes this means there are now three different interfaces
which must be handled.  A zpl_bdi_setup_and_register() wrapper function
has been introduced to provide a single interface to the ZPL code.

* 2.6.32 - 2.6.33, bdi_setup_and_register() is not exported.
* 2.6.34 - 3.19, bdi_setup_and_register() takes 3 arguments.
* 4.0 - x.y, bdi_setup_and_register() takes 2 arguments.

I've also taken this opportunity to remove HAVE_BDI because kernels
older then 2.6.32 are no longer supported.  All kernels newer than
this will have one of the above interfaces.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Chunwei Chen <tuxoko@gmail.com>
Closes #3128
2015-03-03 10:49:45 -08:00
Jörg Thalheim 534759fad3 Linux 3.19 compat: file_inode was added
struct access f->f_dentry->d_inode was replaced by accessor function
file_inode(f)

Signed-off-by: Joerg Thalheim <joerg@higgsboson.tk>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #3084
2015-02-10 11:24:51 -08:00
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
Brian Behlendorf f0e324f25d Update utsname support
Modify the code to use the utsname() kernel function rather than
a global variable.  This results is cleaner more portable code
because utsname() is already provided by the kernel and can be
easily emulated in user space via uname(2).  This means that it
will behave consistently in both contexts.

This is also has the benefit that it allows the removal of a few
_KERNEL pre-processor conditions.  And it also is a pre-requisite
for a proper FUSE port because we need to provide a valid utsname.

Finally, it allows us to remove this functionality from the SPL
and all the related compatibility code.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #2757
2014-10-17 14:58:57 -07:00
Richard Yao 194e56234a Include sys/taskq.h in linux/vfs_compat.h
We should have included sys/taskq.h directly because we use the taskq
code here, but we instead had files that included sys/taskq.h also
include sys/kmem.h, which happened to include sys/taskq.h. sys/kmem.h no
longer does this, so we must define the include as we should
have done in the first place.

Signed-off-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #2411
2014-08-14 12:38:17 -07:00
Chris Wedgwood 62a05896e8 Allow building without ACLs
Some kernel definitions were buried inside the #if... #endif logic for
ACLs.  When ACLs are not available these definitions get lost causing
the build to fail.

Signed-off-by: Chris Wedgwood <cw@f00f.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #2349
2014-05-30 12:01:57 -07:00
Richard Yao 9d317793aa Implement File Attribute Support
We add support for lsattr and chattr to resolve a regression caused
by 88c283952f that broke Python's
xattr.list(). That changet broke Gentoo Portage's FEATURES=xattr,
which depended on Python's xattr.list().

Only attributes common to both Solaris and Linux are supported. These
are 'a', 'd' and 'i' in Linux's lsattr and chattr commands. File
attributes exclusive to Solaris are present in the ZFS code, but cannot
be accessed or modified through this method.  That was the case prior to
this patch. The resolution of issue zfsonlinux/zfs#229 should implement
some method to permit access and modification of Solaris-specific
attributes.

References:
  https://bugs.gentoo.org/show_bug.cgi?id=483516

Original-patch-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #1691
2014-05-01 10:11:18 -07:00
Chunwei Chen b761912b34 Linux 3.14 compat: rq_for_each_segment in dmu_req_copy
rq_for_each_segment changed from taking bio_vec * to taking bio_vec.
We provide rq_for_each_segment4 which takes both.

Signed-off-by: Chunwei Chen <tuxoko@gmail.com>
Signed-off-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #2124
2014-04-10 14:28:51 -07:00
Chunwei Chen d4541210f3 Linux 3.14 compat: Immutable biovec changes in vdev_disk.c
bi_sector, bi_size and bi_idx are moved from bio to bio->bi_iter.
This patch creates BIO_BI_*(bio) macros to hide the differences.

Signed-off-by: Chunwei Chen <tuxoko@gmail.com>
Signed-off-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #2124
2014-04-10 14:28:38 -07:00
Chunwei Chen 408ec0d2e1 Linux 3.14 compat: posix_acl_{create,chmod}
posix_acl_{create,chmod} is changed to __posix_acl_{create_chmod}

Signed-off-by: Chunwei Chen <tuxoko@gmail.com>
Signed-off-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #2124
2014-04-10 14:27:03 -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
Massimo Maggi b695c34ea4 Honor CONFIG_FS_POSIX_ACL kernel option
The required Posix ACL interfaces are only available for kernels
with CONFIG_FS_POSIX_ACL defined.  Therefore, only enable Posix
ACL support for these kernels.  All major distribution kernels
enable CONFIG_FS_POSIX_ACL by default.

If your kernel does not support Posix ACLs the following warning
will be printed at ZFS module load time.

  "ZFS: Posix ACLs disabled by kernel"

Signed-off-by: Massimo Maggi <me@massimo-maggi.eu>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #1825
2013-11-05 16:22:05 -08:00
Massimo Maggi 023699cd62 Posix ACL Support
This change adds support for Posix ACLs by storing them as an xattr
which is common practice for many Linux file systems.  Since the
Posix ACL is stored as an xattr it will not overwrite any existing
ZFS/NFSv4 ACLs which may have been set.  The Posix ACL will also
be non-functional on other platforms although it may be visible
as an xattr if that platform understands SA based xattrs.

By default Posix ACLs are disabled but they may be enabled with
the new 'aclmode=noacl|posixacl' property.  Set the property to
'posixacl' to enable them.  If ZFS/NFSv4 ACL support is ever added
an appropriate acltype will be added.

This change passes the POSIX Test Suite cleanly with the exception
of xacl/00.t test 45 which is incorrect for Linux (Ext4 fails too).

  http://www.tuxera.com/community/posix-test-suite/

Signed-off-by: Massimo Maggi <me@massimo-maggi.eu>
Signed-off-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #170
2013-10-29 14:54:26 -07:00
Li Dongyang 802e7b5feb Add SEEK_DATA/SEEK_HOLE to lseek()/llseek()
The approach taken was the rework zfs_holey() as little as
possible and then just wrap the code as needed to ensure
correct locking and error handling.

Tested with xfstests 285 and 286.  All tests pass except for
7-9 of 285 which try to reserve blocks first via fallocate(2)
and fail because fallocate(2) is not yet supported.

Note that the filp->f_lock spinlock did not exist prior to
Linux 2.6.30, but we avoid the need for autotools check by
virtue of the fact that SEEK_DATA/SEEK_HOLE support was not
added until Linux 3.1.

An autoconf check was added for lseek_execute() which is
currently a private function but the expectation is that it
will be exported perhaps as early as Linux 3.11.

Reviewed-by: Richard Laager <rlaager@wiktel.com>
Signed-off-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #1384
2013-07-02 09:24:43 -07:00
Brian Behlendorf 88c283952f Return -EOPNOTSUPP for ZFS_IOC_{GET|SET}FLAGS
Until these hooks are fully implemented return the expected
-EOPNOTSUPP error to indicate they are not functional.  This
allows test suites such as xfstests to cleanly skip testing
this functionality until it's implemented.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #229
2013-06-26 15:20:13 -07:00
Ying Zhu 6822a0d058 Fix compile warning on 32-bit systems
The definition of zfs_vdev_holder casts VDEV_HOLDER into a function pointer
passing to linux kernel's block layer function blkdev_get_by_path.
However current VDEV_HOLDER is defined to be wider than 32 bits and the compiler
warns about potential overflows. Instead of specifying different values for 32-bit and
64-bit systems using ifdefs, choose the common factor 32-bit addresses.
Redefine VDEV_HOLDER to 0x2401de7("zholder") here.

Signed-off-by: Ying Zhu <casualfisher@gmail.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #1520
2013-06-19 17:11:55 -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
Brian Behlendorf 8128bd89fb Fix hot spares
The issue with hot spares in ZoL is because it opens all leaf
vdevs exclusively (O_EXCL).  On Linux, exclusive opens cause
subsequent exclusive opens to fail with EBUSY.

This could be resolved by not opening any of the devices
exclusively, which is what Illumos does, but the additional
protection offered by exclusive opens is desirable.  It cleanly
prevents you from accidentally adding an in-use non-ZFS device
to your pool.

To fix this we very slightly relaxed the usage of O_EXCL in
the following ways.

1) Functions which open the device but only read had the
   O_EXCL flag removed and were updated to use O_RDONLY.

2) A common holder was added to the vdev disk code.  This
   allow the ZFS code to internally open the device multiple
   times but non-ZFS callers may not.

3) An exception was added to make_disks() for hot spare when
   creating partition tables.  For hot spare devices which
   are already opened exclusively we skip creating the partition
   table because this must already have been done when the disk
   was originally added as a hot spare.

Additional minor changes include fixing check_in_use() to use
a partition instead of a slice suffix.  And is_spare() was moved
above make_disks() to avoid adding a forward reference.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #250
2013-03-01 13:31:02 -08:00
Brian Behlendorf 2b7ab9d4d9 Linux 2.6.26 compat, lookup_bdev()
It's doubtful many people were impacted by this but commit 6c28567
accidentally broke ZFS builds for 2.6.26 and earlier kernels.  This
commit depends on the lookup_bdev() function which exists in 2.6.26
but wasn't exported until 2.6.27.

The availability of the function isn't critical so a wrapper is
introduced which returns ERR_PTR(-ENOTSUP) when the function isn't
defined.  This will have the effect of causing zvol_is_zvol() to
always fail for 2.6.26 kernels.  This in turn means vdevs will
always get opened concurrently which is good for normal usage.
This will only become an issue if your using a zvol as a vdev in
another pool.  In which case you really should be using a newer
kernel anyway.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #1205
2013-01-28 15:35:00 -08:00
Brian Behlendorf bf01b5e616 Add d_clear_d_op() compatibility
Added d_clear_d_op() helper function which clears some flags and the
registered dentry->d_op table.  This is required because d_set_d_op()
issues a warning when the dentry operations table is already set.
For the .zfs control directory to work properly we must be able to
override the default operations table and register custom .d_automount
and .d_revalidate callbacks.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ned Bass <bass6@llnl.gov>
Closes #1230
2013-01-23 16:33:29 -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
Ned Bass f1a05fa114 Fix false ENOENT on snapshot control dentries
Lookups in the snapshot control directory for an existing snapshot
fail with ENOENT if an earlier lookup failed before the snapshot was
created.  This is because the earlier lookup causes a negative dentry
to be cached which is never invalidated.

The bug can be reproduced as follows (the second ls should succeed):

 $ ls /tank/.zfs/snapshot/s
 ls: cannot access /tank/.zfs/snapshot/s: No such file or directory
 $ zfs snap tank@s
 $ ls /tank/.zfs/snapshot/s
 ls: cannot access /tank/.zfs/snapshot/s: No such file or directory

To remedy this, always invalidate cached dentries in the snapshot
control directory.  Since these entries never exist on disk there is
no significant performance penalty for the extra lookups.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #1192
2013-01-16 16:28:54 -08:00
Brian Behlendorf 2404b01499 Improve AF hard disk detection
Use the bdev_physical_block_size() interface to determine the
minimize write size which can be issued without incurring a
read-modify-write operation.  This is used to set the ashift
correctly to prevent a performance penalty when using AF hard
disks.

Unfortunately, this interface isn't entirely reliable because
it's not uncommon for disks to misreport this value.  For this
reason you may still need to manually set your ashift with:

  zpool create -o ashift=12 ...

The solution to this in the upstream Illumos source was to add
a white list of known offending drives.  Maintaining such a list
will be a burden, but it still may be worth doing if we can
detect a large number of these drives.  This should be considered
as future work.

Reported-by: Richard Yao <ryao@cs.stonybrook.edu>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #916
2012-11-15 11:06:14 -08:00
Richard Yao 95f5c63b47 Linux 3.6 compat, iops->mkdir()
Use .mkdir instead of .create in 3.3 compatibility check.  Linux 3.6
modifies inode_operations->create's function prototype. This causes
an autotools Linux 3.3. compatibility check for a function prototype
change in create, mkdir and mknode to fail. Since mkdir and mknode
are unchanged, we modify the check to examine it instead.

Signed-off-by: Richard Yao <ryao@cs.stonybrook.edu>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #873
2012-10-14 15:29:26 -07:00
Yuxuan Shui 3c20361075 Linux 3.6 compat, sget()
As of Linux commit 9249e17fe094d853d1ef7475dd559a2cc7e23d42 the
mount flags are now passed to sget() so they can be used when
initializing a new superblock.

ZFS never uses sget() in this fashion so we can simply pass a
zero and add a zpl_sget() compatibility wrapper.

Signed-off-by: Yuxuan Shui <yshuiv7@gmail.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #873
2012-10-14 13:06:48 -07:00
Brian Behlendorf cda4db408c Revert "Improve AF hard disk detection"
This reverts commit 395350c85d which
accidentally introduced issue #955.

Pools using AF drives which were originally created with a sector
size of 512 bytes will now be correctly detected to have physical
sector size of 4096.  This is desirable for a new pool, however for
an existing pool abruptly changing the sector size causes problems.

For this reason, this change is being reverted until the additional
logic can be added to detect the existing pool case.  Existing
pools must use the ashift size stored in the label regardless of
what the disk reports.  This is critical for compatibility.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #955
2012-09-11 16:33:49 -07:00
Brian Behlendorf 395350c85d Improve AF hard disk detection
Use the bdev_physical_block_size() interface to determine the
minimize write size which can be issued without incurring a
read-modify-write operation.  This is used to set the ashift
correctly to prevent a performance penalty when using AF hard
disks.

Unfortunately, this interface isn't entirely reliable because
it's not uncommon for disks to misreport this value.  For this
reason you may still need to manually set your ashift with:

  zpool create -o ashift=12 ...

The solution to this in the upstream Illumos source was to add
a while list of known offending drives.  Maintaining such a list
will be a burden, but it still may be worth doing if we can
detect a large number of these drives.  This should be considered
as future work.

Reported-by: Richard Yao <ryao@cs.stonybrook.edu>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #916
2012-09-04 15:35:32 -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