Linux 3.12 compat: shrinker semantics

The new shrinker API as of Linux 3.12 modifies "struct shrinker" by
replacing the @shrink callback with the pair of @count_objects and
@scan_objects.  It also requires the return value of @count_objects to
return the number of objects actually freed whereas the previous @shrink
callback returned the number of remaining freeable objects.

This patch adds support for the new @scan_objects return value semantics.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Tim Chase <tim@chase2k.com>
Closes #2837
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
Search /usr/local/src for SPL Object Directory

Since we changed the default location for the kernel headers to respect
--prefix in the SPL, we must search that location to prevent user builds
from breaking.

Signed-off-by: Richard Yao <richard.yao@clusterhq.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #2641
Make directory into which mount.zfs is installed configurable

Installing outside of the prefix is not permissible under Gentoo Prefix.
The package manager will cause the installation process to fail if/when
it sees this. I could script a workaround inside the ebuild, but it
seemed to make more sense to make this more configurable.

Signed-off-by: Richard Yao <richard.yao@clusterhq.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #2641
Make systemd-modules-load.service file directory configurable

Installing outside of the prefix is not permissible under Gentoo Prefix.
The package manager will cause the installation process to fail if/when
it sees this. We could handle this by disabling systemd support on
prefix because systemd does not check these paths, but the Gentoo
Council decided that small files such as these should be installed.
That means disabling systemd support on prefix is not an acceptable
workaround. As a consequence, we need some way of control the directory
into which these files are installed.

Making this configurable increases our compliance with the
freedesktop.org specification, which allows these files to be installed
into /etc/modules-load.d:

http://www.freedesktop.org/software/systemd/man/modules-load.d.html

Signed-off-by: Richard Yao <richard.yao@clusterhq.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #2641
Fix modules installation directory

When building zfs modules with kernel, compiled from deb.src, the
packaging process ends up installing the modules in the wrong place.

Signed-off-by: Alexander Pyhalov <apyhalov@gmail.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #2822
Add config/compile to config/.gitignore

This file may be added by automake and therefore should be added
to config/.gitignore.  For the full list of possible auxiliary
programs see the full automake documentation.

http://www.gnu.org/software/automake/manual/automake.html#Auxiliary-Programs

Signed-off-by: Marcel Wysocki <maci.stgn@gmail.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #2848
Improve zvol symlink handling.

Change the zvol helper program to replace any embedded spaces
in the pool or dataset names with '+' to ensure we have valid
symlinks.

The '+' character was choosen because it is not a valid character
for a dataset name but it is allowed by udev.  This ensures that
all dataset names with an embedded space will be translated to
a unique /dev/zvol/ symlink.

Signed-off-by: Dan Swartzendruber <dswartz@druber.com>
Signed-off-by: Darik Horn <dajhorn@vanadac.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #2834
Using the atomics around the vnode_create() only protected us from calls
starting in ZFS, not from other consumers (HFS+) which can also end up
calling fsync/pageout/reclaim. Since vclean() sets VL_TERMINATE before
calling all 3 VNOPs, we use vnode_isrecycled() to test for that and ignore
the request (since we know vnop_reclaim will also be called).
Merge
Export symbols for ZIL interface

These symbols are needed by consumers (i.e. Lustre) who wish to
integrate with the ZIL.  In addition the zil_rollback_destroy()
prototype was removed because the implementation of this function
was removed long ago.

Signed-off-by: Alex Zhuravlev <alexey.zhuravlev@intel.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #2892
Reduce buf/dbuf mutex contention

Due to evidence of contention both the buf_hash_table and the
dbuf_hash_table sizes have been increased from 256 to 8192.

This increase in hash table size adds approximating 0.5M to
our fixed memory footprint.  This relatively small increase
is not expected to cause problems even on low memory machines.
This footprint will also become dynamic when the persistent
L2ARC support is finalized.  In the meanwhile, this small
change significantly reduces contention for certain workloads.

Signed-off-by: Chris Wedgwood <cw@f00f.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Pavel Snajdr <snajpa@snajpa.net>
Closes #1291
Fix inaccurate field descriptions

The field descriptions from arcstat.py -v for the demand accesses
are inaccurate. They all begin with "Demand Data" yet the fields
actually covered both demand data and demand meta-data accesses.

Signed-off-by: Isaac Huang <he.huang@intel.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #2842
Print header properly when terminal resizes

Added a handler for SIGWINCH, so that one header
is printed per screen even when the terminal resizes.

Signed-off-by: Isaac Huang <he.huang@intel.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #2847
Illumos 5213 - panic in metaslab_init due to space_map_open returning ENXIO

5213 panic in metaslab_init due to space_map_open returning ENXIO
Reviewed by: Matthew Ahrens mahrens@delphix.com
Reviewed by: George Wilson george.wilson@delphix.com

References:
  https://www.illumos.org/issues/5213
  https://reviews.csiden.org/r/110

Porting notes:

For the Linux port, KM_SLEEP was replaced with KM_PUSHPAGE.

Ported by: Turbo Fredriksson <turbo@bayour.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #2745
Fix small spelling mistake

recieve becomes receive

Signed-off-by: Randall Mason <ClashTheBunny@gmail.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #2877
vnop_remove fastpath

Attempt to enable the delete fastpath from Illumos, instead of always using
unlinkedlist, with inactive_drain.
In XNU you can not force a release a vnode, only via calling vnode_recycle,
and you can not assume it is gone unless that succeeds (and vnop_reclaim
is called).  This mean zfs_znode_delete() can't be called directly, but
rather as for recycle. The fastpath will do the same, setting z_fastpath
to let vnop_reclaim know to not actually release it. If recycle comes
back successful we can release the zp. Otherwise fallback to using
unlinkedlist.
On zfs recv of a zvol, call zvol_create_minors
Merge pull request #248 from openzfsonosx/recv-zvol

On zfs recv of a zvol, call zvol_create_minors
Improved reclaim work.

Attempt to do as much direct reclaim as possible, and only defer
to the reclaim thread in the one special case.
This means we finally release the contents of XATTR dirs, as well as
delete fastpath.

Note that the first import after this patch will most likely take
considerably longer, due to finally releasing the unlinked list.