Commit Graph

101 Commits

Author SHA1 Message Date
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
Turbo Fredriksson
47a4a6fd5f Support parallel build trees (VPATH builds)
Build products from an out of tree build should be written
relative to the build directory.  Sources should be referred
to by their locations in the source directory.

This is accomplished by adding the 'src' and 'obj' variables
for the module Makefile.am, using relative paths to reference
source files, and by setting VPATH when source files are not
co-located with the Makefile.  This enables the following:

  $ mkdir build
  $ cd build
  $ ../configure \
    --with-spl=$HOME/src/git/spl/ \
    --with-spl-obj=$HOME/src/git/spl/build
  $ make -s

This change also has the advantage of resolving the following
warning which is generated by modern versions of automake.

  Makefile.am:00: warning: source file 'xxx' is in a subdirectory,
  Makefile.am:00: but option 'subdir-objects' is disabled

Signed-off-by: Turbo Fredriksson <turbo@bayour.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #1082
2015-07-17 13:42:51 -07:00
Brian Behlendorf
bd29109f1a Linux 4.2 compat: follow_link() / put_link()
As of Linux 4.2 the kernel has completely retired the nameidata
structure.  One of the few remaining consumers of this interface
were the follow_link() and put_link() callbacks.

This patch adds the required checks to configure to detect the
interface change and updates the functions accordingly.  Migrating
to the simple_follow_link() interface was considered but was decided
against ironically due to the increased complexity.

It also should be noted that the kernel follow_link() and put_link()
interfaces changes several times after 4.1 and but before 4.2.  This
means there is a narrow range of kernel commits which never appear
in an official tag of the Linux kernel which ZoL will not build.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Richard Yao <ryao@gentoo.org>
Issue #3596
2015-07-17 09:18:16 -07:00
Brian Behlendorf
c2d17fd891 Disable gcc bool-compare warning
As of gcc version 5.1.1 a new boolean comparison warning has been
introduced.  This warning is harmless but is triggered several places
in the ZFS code base.  Because warnings are promoted to errors when
building with debugging enabled it is necessary to disable the warning
when using versions of gcc which automatically enabling this check.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2015-07-13 12:55:26 -07:00
Brian Behlendorf
218b4e0a76 Add zfs_sb_prune_aliases() function
For kernels which do not implement a per-suberblock shrinker,
those older than Linux 3.1, the shrink_dcache_parent() function
was used to attempt to reclaim dentries.  This was found not be
entirely reliable and could lead to performance issues on older
kernels running meta-data heavy workloads.

To address this issue a zfs_sb_prune_aliases() function has been
added to implement this functionality.  It relies on traversing
the list of znodes for a filesystem and adding them to a private
list with a reference held.  The private list can then be safely
walked outside the z_znodes_lock to prune dentires and drop the
last reference so the inode can be freed.

This provides the same synchronous behavior as the per-filesystem
shrinker and has the advantage of depending on only long standing
interfaces.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Tim Chase <tim@chase2k.com>
Closes #3501
2015-06-22 10:22:49 -07:00
Matus Kral
57ae840077 Linux 4.1 compat: use read_iter() / write_iter()
Linux 3.15 commit torvalds/linux@293bc98 introduced two new methods.
The ->read_iter() and ->write_iter() methods were designed to replace
the ->aio_read() and ->aio_write() interfaces.  Both interfaces were
preserved for several kernel releases in order to migrate all existing
consumers to the new interfaces.  But as of Linux 4.1 the legacy
interface has been retired and the ZFS code must be updated to use
the new interfaces.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #3352
2015-06-18 12:06:59 -07:00
Tim Chase
90947b2357 3.12 compat, NUMA-aware per-superblock shrinker
Kernels >= 3.12 have a NUMA-aware superblock shrinker which is used in
ZoL by zfs_sb_prune().  This patch calls the shrinker for each on-line
NUMA node in order that memory be freed for each one.

Signed-off-by: Tim Chase <tim@chase2k.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #3495
2015-06-17 10:43:13 -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
Ned Bass
4e30e68caf Don't use AC_LANG_SOURCE for conftest.h source
Using AC_LANG_SOURCE with some versions of autoconf is problematic if
the given source is to be written to a header file. Such versions assume
the contents are to be written to conftest.c and generate shell code to
that effect. The contents of the test program to detect support for
Linux tracepoints were consequently malformed (containing the source for
conftest.h) so the build system incorrectly disabled tracepoints
support. Fix this in ZFS_LINUX_TRY_COMPILE_HEADER by passing the header
source directly to ZFS_LINUX_COMPILE_IFELSE.

Signed-off-by: Ned Bass <bass6@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #2953
2015-01-06 16:53:30 -08:00
Prakash Surya
0b39b9f96f Swap DTRACE_PROBE* with Linux tracepoints
This patch leverages Linux tracepoints from within the ZFS on Linux
code base. It also refactors the debug code to bring it back in sync
with Illumos.

The information exported via tracepoints can be used for a variety of
reasons (e.g. debugging, tuning, general exploration/understanding,
etc). It is advantageous to use Linux tracepoints as the mechanism to
export this kind of information (as opposed to something else) for a
number of reasons:

    * A number of external tools can make use of our tracepoints
      "automatically" (e.g. perf, systemtap)
    * Tracepoints are designed to be extremely cheap when disabled
    * It's one of the "accepted" ways to export this kind of
      information; many other kernel subsystems use tracepoints too.

Unfortunately, though, there are a few caveats as well:

    * Linux tracepoints appear to only be available to GPL licensed
      modules due to the way certain kernel functions are exported.
      Thus, to actually make use of the tracepoints introduced by this
      patch, one might have to patch and re-compile the kernel;
      exporting the necessary functions to non-GPL modules.

    * Prior to upstream kernel version v3.14-rc6-30-g66cc69e, Linux
      tracepoints are not available for unsigned kernel modules
      (tracepoints will get disabled due to the module's 'F' taint).
      Thus, one either has to sign the zfs kernel module prior to
      loading it, or use a kernel versioned v3.14-rc6-30-g66cc69e or
      newer.

Assuming the above two requirements are satisfied, lets look at an
example of how this patch can be used and what information it exposes
(all commands run as 'root'):

    # list all zfs tracepoints available

    $ ls /sys/kernel/debug/tracing/events/zfs
    enable              filter              zfs_arc__delete
    zfs_arc__evict      zfs_arc__hit        zfs_arc__miss
    zfs_l2arc__evict    zfs_l2arc__hit      zfs_l2arc__iodone
    zfs_l2arc__miss     zfs_l2arc__read     zfs_l2arc__write
    zfs_new_state__mfu  zfs_new_state__mru

    # enable all zfs tracepoints, clear the tracepoint ring buffer

    $ echo 1 > /sys/kernel/debug/tracing/events/zfs/enable
    $ echo 0 > /sys/kernel/debug/tracing/trace

    # import zpool called 'tank', inspect tracepoint data (each line was
    # truncated, they're too long for a commit message otherwise)

    $ zpool import tank
    $ cat /sys/kernel/debug/tracing/trace | head -n35
    # tracer: nop
    #
    # entries-in-buffer/entries-written: 1219/1219   #P:8
    #
    #                              _-----=> irqs-off
    #                             / _----=> need-resched
    #                            | / _---=> hardirq/softirq
    #                            || / _--=> preempt-depth
    #                            ||| /     delay
    #           TASK-PID   CPU#  ||||    TIMESTAMP  FUNCTION
    #              | |       |   ||||       |         |
            lt-zpool-30132 [003] .... 91344.200050: zfs_arc__miss: hdr...
          z_rd_int/0-30156 [003] .... 91344.200611: zfs_new_state__mru...
            lt-zpool-30132 [003] .... 91344.201173: zfs_arc__miss: hdr...
          z_rd_int/1-30157 [003] .... 91344.201756: zfs_new_state__mru...
            lt-zpool-30132 [003] .... 91344.201795: zfs_arc__miss: hdr...
          z_rd_int/2-30158 [003] .... 91344.202099: zfs_new_state__mru...
            lt-zpool-30132 [003] .... 91344.202126: zfs_arc__hit: hdr ...
            lt-zpool-30132 [003] .... 91344.202130: zfs_arc__hit: hdr ...
            lt-zpool-30132 [003] .... 91344.202134: zfs_arc__hit: hdr ...
            lt-zpool-30132 [003] .... 91344.202146: zfs_arc__miss: hdr...
          z_rd_int/3-30159 [003] .... 91344.202457: zfs_new_state__mru...
            lt-zpool-30132 [003] .... 91344.202484: zfs_arc__miss: hdr...
          z_rd_int/4-30160 [003] .... 91344.202866: zfs_new_state__mru...
            lt-zpool-30132 [003] .... 91344.202891: zfs_arc__hit: hdr ...
            lt-zpool-30132 [001] .... 91344.203034: zfs_arc__miss: hdr...
          z_rd_iss/1-30149 [001] .... 91344.203749: zfs_new_state__mru...
            lt-zpool-30132 [001] .... 91344.203789: zfs_arc__hit: hdr ...
            lt-zpool-30132 [001] .... 91344.203878: zfs_arc__miss: hdr...
          z_rd_iss/3-30151 [001] .... 91344.204315: zfs_new_state__mru...
            lt-zpool-30132 [001] .... 91344.204332: zfs_arc__hit: hdr ...
            lt-zpool-30132 [001] .... 91344.204337: zfs_arc__hit: hdr ...
            lt-zpool-30132 [001] .... 91344.204352: zfs_arc__hit: hdr ...
            lt-zpool-30132 [001] .... 91344.204356: zfs_arc__hit: hdr ...
            lt-zpool-30132 [001] .... 91344.204360: zfs_arc__hit: hdr ...

To highlight the kind of detailed information that is being exported
using this infrastructure, I've taken the first tracepoint line from the
output above and reformatted it such that it fits in 80 columns:

    lt-zpool-30132 [003] .... 91344.200050: zfs_arc__miss:
        hdr {
            dva 0x1:0x40082
            birth 15491
            cksum0 0x163edbff3a
            flags 0x640
            datacnt 1
            type 1
            size 2048
            spa 3133524293419867460
            state_type 0
            access 0
            mru_hits 0
            mru_ghost_hits 0
            mfu_hits 0
            mfu_ghost_hits 0
            l2_hits 0
            refcount 1
        } bp {
            dva0 0x1:0x40082
            dva1 0x1:0x3000e5
            dva2 0x1:0x5a006e
            cksum 0x163edbff3a:0x75af30b3dd6:0x1499263ff5f2b:0x288bd118815e00
            lsize 2048
        } zb {
            objset 0
            object 0
            level -1
            blkid 0
        }

For the specific tracepoint shown here, 'zfs_arc__miss', data is
exported detailing the arc_buf_hdr_t (hdr), blkptr_t (bp), and
zbookmark_t (zb) that caused the ARC miss (down to the exact DVA!).
This kind of precise and detailed information can be extremely valuable
when trying to answer certain kinds of questions.

For anybody unfamiliar but looking to build on this, I found the XFS
source code along with the following three web links to be extremely
helpful:

    * http://lwn.net/Articles/379903/
    * http://lwn.net/Articles/381064/
    * http://lwn.net/Articles/383362/

I should also node the more "boring" aspects of this patch:

    * The ZFS_LINUX_COMPILE_IFELSE autoconf macro was modified to
       support a sixth paramter. This parameter is used to populate the
       contents of the new conftest.h file. If no sixth parameter is
       provided, conftest.h will be empty.

    * The ZFS_LINUX_TRY_COMPILE_HEADER autoconf macro was introduced.
      This macro is nearly identical to the ZFS_LINUX_TRY_COMPILE macro,
      except it has support for a fifth option that is then passed as
      the sixth parameter to ZFS_LINUX_COMPILE_IFELSE.

These autoconf changes were needed to test the availability of the Linux
tracepoint macros. Due to the odd nature of the Linux tracepoint macro
API, a separate ".h" must be created (the path and filename is used
internally by the kernel's define_trace.h file).

    * The HAVE_DECLARE_EVENT_CLASS autoconf macro was introduced. This
      is to determine if we can safely enable the Linux tracepoint
      functionality. We need to selectively disable the tracepoint code
      due to the kernel exporting certain functions as GPL only. Without
      this check, the build process will fail at link time.

In addition, the SET_ERROR macro was modified into a tracepoint as well.
To do this, the 'sdt.h' file was moved into the 'include/sys' directory
and now contains a userspace portion and a kernel space portion. The
dprintf and zfs_dbgmsg* interfaces are now implemented as tracepoint as
well.

Signed-off-by: Prakash Surya <surya1@llnl.gov>
Signed-off-by: Ned Bass <bass6@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2014-11-17 11:13:55 -08:00
Richard Yao
d8d7826721 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
2014-10-28 09:37:23 -07:00
Brian Behlendorf
e33045ee98 Make license compatibility checks consistent
Apply the license specified in the META file to ensure the
compatibility checks are all performed consistently.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #2757
2014-10-17 14:58:38 -07:00
Brian Behlendorf
1139491da7 Revert "Disable GCCs aggressive loop optimization"
This reverts commit 0f62f3f9ab.

Signed-off-by: Tim Chase <tim@chase2k.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #2010
2014-07-22 09:56:55 -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
Brian Behlendorf
0f62f3f9ab Disable GCCs aggressive loop optimization
GCC >+ 4.8's aggressive loop optimization breaks some of the iterators
over the dn_blkptr[] pseudo-array in dnode_phys. Since dn_blkptr[] is
defined as a single-element array, GCC believes an iterator can only
access index 0 and will unroll the loop into a single iteration.

One way to resolve the issue would be to cast the array to a pointer
and fix all the iterators that might break.  The only loop where it
is known to cause a problem is this loop in dmu_objset_write_ready():

    for (i = 0; i < dnp->dn_nblkptr; i++)
            bp->blk_fill += dnp->dn_blkptr[i].blk_fill;

In the common case where dn_nblkptr is 3, the loop is only executed a
single time and "i" is equal to 1 following the loop.

The specific breakage caused by this problem is that the blk_fill of
root block pointers wouldn't be set properly when more than one blkptr
is in use (when no indrect blocks are needed).

The simple reproducing sequence is:

zpool create tank /tank.img
zdb -ddddd tank 0

Notice that "fill=31", however, there are two L0 indirect blocks with
"F=31" and "F=5". The fill count should be 36 rather than 31. This
problem causes an assert to be hit in a simple "zdb tank" when built
with --enable-debug.

However, this approach was not taken because we need to be absolutely
sure we catch all instances of this unwanted optimization.  Therefore,
the build system has been updated to detect if GCC supports the
aggressive loop optimization.  If it does the optimization will be
explicitly disabled using the -fno-aggressive-loop-optimization option.

Original-fix-by: Tim Chase <tim@chase2k.com>
Signed-off-by: Tim Chase <tim@chase2k.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #2010
Closes #2051
2014-01-14 13:55:58 -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
Richard Yao
0f37d0c8be Linux 3.11 compat: fops->iterate()
Commit torvalds/linux@2233f31aad
replaced ->readdir() with ->iterate() in struct file_operations.
All filesystems must now use the new ->iterate method.

To handle this the code was reworked to use the new ->iterate
interface.  Care was taken to keep the majority of changes
confined to the ZPL layer which is already Linux specific.
However, minor changes were required to the common zfs_readdir()
function.

Compatibility with older kernels was accomplished by adding
versions of the trivial dir_emit* helper functions.  Also the
various *_readdir() functions were reworked in to wrappers
which create a dir_context structure to pass to the new
*_iterate() functions.

Unfortunately, the new dir_emit* functions prevent us from
passing a private pointer to the filldir function.  The xattr
directory code leveraged this ability through zfs_readdir()
to generate the list of xattr names.  Since we can no longer
use zfs_readdir() a simplified zpl_xattr_readdir() function
was added to perform the same task.

Signed-off-by: Richard Yao <ryao@cs.stonybrook.edu>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #1653
Issue #1591
2013-08-15 16:19:07 -07:00
Brian Behlendorf
dba1d70566 Fix arc_adapt() spinning in iterate_supers_type()
The iterate_supers_type() function which was introduced in the
3.0 kernel was supposed to provide a safe way to call an arbitrary
function on all super blocks of a specific type.  Unfortunately,
because a list_head was used a bug was introduced which made it
possible for iterate_supers_type() to get stuck spinning on a
super block which was just deactivated.

This can occur because when the list head is removed from the
fs_supers list it is reinitialized to point to itself.  If the
iterate_supers_type() function happened to be processing the
removed list_head it will get stuck spinning on that list_head.

The bug was fixed in the 3.3 kernel by converting the list_head
to an hlist_node.  However, to resolve the issue for existing
3.0 - 3.2 kernels we detect when a list_head is used.  Then to
prevent the spinning from occurring the .next pointer is set to
the fs_supers list_head which ensures the iterate_supers_type()
function will always terminate.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #1045
Closes #861
Closes #790
2013-07-17 09:28:06 -07:00
Chris Dunlop
a1d9543a39 3.10 API change: block_device_operations->release() returns void
Linux kernel commit torvalds/linux@db2a144 changed the return type
of block_device_operations->release() to void.  Detect the expected
prototype and defined our callout accordingly.

Signed-off-by: Chris Dunlop <chris@onthe.net.au>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #1494
2013-07-08 15:41:57 -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
Carlos Alberto Lopez Perez
5165473737 Ensure --with-spl-timeout waits for spl_config.h and symvers
The previous code was only waiting for the symver file. But the
postinst target of the DKMS script for SPL will not only create
the symvers file, but also the header spl_config.h.

If we are waiting in the configure script of ZFS for the SPL
symvers file, then we also need to wait for spl_config.h.
Otherwise the configure script will abort because the spl_config.h
is not yet available.

On top of that, the function ZFS_AC_SPL_MODULE_SYMVERS is moved
to the end of the function ZFS_AC_SPL to allow both checks share
the with-spl-timeout parameter.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #1431
2013-05-02 15:40:44 -07:00
Jan Engelhardt
4e95cc99b0 build: resolve orthographic and other grammatical errors
Signed-off-by: Jan Engelhardt <jengelh@inai.de>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2013-04-02 10:44:52 -07:00
Brian Behlendorf
9b2af9a097 Configure --with-spl{-obj} auto-detect cleanup
Because the install location for the spl/zfs-devel headers was
changed we need to refresh the auto-detect code.  Note that
for packaging which already explicitly calls --with-spl{-obj}
nothing has changed.

The updated code is now structured like that in ZFS_AC_KERNEL
and should be cleaner and easier to maintain.  In addition,
it's stricter about detecting a valid source and object
directory.  It requires:

* The source directory contains the file 'spl.release'
* The object directory contains the file 'spl_config.h'
* The following paths will be checked.  Notice the /var/lib/
  and /usr/src paths require that the spl and zfs version be
  matched.  This is done to prevent accidentally mixing releases.

        dnl # 1) /var/lib/dkms/spl/<version>/build
        dnl # 2) /usr/src/spl-<version>/<kernel-version>
        dnl # 3) /usr/src/spl-<version>
        dnl # 4) ../spl
        dnl # 5) /usr/src/kernels/<kernel-version>

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2013-03-13 13:42:16 -07:00
Etienne Dechamps
d9b0ebbe82 Remove the bio_empty_barrier() check.
To determine whether the kernel is capable of handling empty barrier
BIOs, we check for the presence of the bio_empty_barrier() macro,
which was introduced in 2.6.24. If this macro is defined, then we can
flush disk vdevs; if it isn't, then flushing is disabled.

Unfortunately, the bio_empty_barrier() macro was removed in 2.6.37,
even though the kernel is still capable of handling empty barrier BIOs.

As a result, flushing is effectively disabled on kernels >= 2.6.37,
meaning that starting from this kernel version, zfs doesn't use
barriers to guarantee on-disk data consistency. This is quite bad and
can lead to potential data corruption on power failures.

This patch fixes the issue by removing the configure check for
bio_empty_barrier(), as we don't support kernels <= 2.6.24 anymore.

Thanks to Richard Kojedzinszky for catching this nasty bug.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #1318
2013-02-24 10:22:34 -08:00
Etienne Dechamps
d75af3c0eb Use -Werror for all kernel configure tests.
As a matter of fact, we're already using -Werror for most tests because
of a bug in kernel-bio-empty-barrier.m4 which sets -Werror without
reverting it afterwards. This meant that all tests which ran after this
one was using -Werror.

This patch simply makes it clear that we're using -Werror and makes
the code more readable and more predictable.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #1317
2013-02-24 10:20:28 -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
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
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
8780c53961 Update SAs when an inode is dirtied
Revert the portion of commit d3aa3ea which always resulted in the
SAs being update when an mmap()'ed file was closed.  That change
accidentally resulted in unexpected ctime updates which upset tools
like git.  That was always a horrible hack and I'm happy it will
never make it in to a tagged release.

The right fix is something I initially resisted doing because I
was worried about the additional overhead.  However, in hindsight
the overhead isn't as bad as I feared.

This patch implemented the sops->dirty_inode() callback which is
unsurprisingly called when an inode is dirtied.  We leverage this
callback to keep the znode SAs strictly in sync with the inode.

However, for now we're going to go slowly to avoid introducing
any new unexpected issues by only updating the atime, mtime, and
ctime.  This will cover the callpath of most concern to us.

  ->filemap_page_mkwrite->file_update_time->update_time->
      mark_inode_dirty_sync->__mark_inode_dirty->dirty_inode

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #764
Closes #1140
2012-12-14 12:18:54 -08:00
Brian Behlendorf
56a517ae3a Verify --with-linux source directory exists
Previously this check was only performed when ./configure was
attempting to autodetect your kernel source directory.  But we
should also handle the case where --with-linux was provided
and is obviously wrong.  This way we catch the error before
invoking make and compiling the source with an incorrect
autoconf results.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes zfsonlinux/spl#162
2012-11-29 15:08:35 -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
558ef6d080 Linux 3.6 compat, iops->create()
As of Linux commit ebfc3b49a7ac25920cb5be5445f602e51d2ea559 the
struct nameidata is no longer passed to iops->create.  Instead
only the result of (inamedata->flags & LOOKUP_EXCL) is passed.

ZFS like almost all Linux fileystems never made use of this so
only the prototype needs to be wrapped for compatibility.

Signed-off-by: Yuxuan Shui <yshuiv7@gmail.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #873
2012-10-14 14:42:25 -07:00
Yuxuan Shui
8f195a908f Linux 3.6 compat, iops->lookup()
As of Linux commit 00cd8dd3bf95f2cc8435b4cac01d9995635c6d0b the
struct nameidata is no longer passed to iops->lookup.  Instead
only the inamedata->flags are passed.

ZFS like almost all Linux fileystems never made use of this so
only the prototype needs to be wrapped for compatibility.

Signed-off-by: Yuxuan Shui <yshuiv7@gmail.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #873
2012-10-14 13:06:54 -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
6d1d976b2c Modify vdev_elevator_switch() to use elevator_change()
As of Linux 2.6.36 an elevator_change() interface was added.
This commit updates vdev_elevator_switch() to use this interface
when available, otherwise it falls back to the usermodehelper
method.

Original-patch-by: foobarz <sysop@xeon.(none)>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #906
2012-10-03 13:31:44 -07:00
Cyril Plisko
393b44c711 Implement .commit_metadata hook for NFS export
In order to implement synchronous NFS metadata semantics ZFS
needs to provide the .commit_metadata hook.  All it takes there
is to make sure changes are committed to ZIL.  Fortunately
zfs_fsync() does just that, so simply calling it from
zpl_commit_metadata() does the trick.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #969
2012-10-03 10:49:45 -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
Prakash Surya
f86373f5b2 Remove autoconf check for CONFIG_PREEMPT
The autoconf macro which failed if CONFIG_PREEMPT was set in the kernel
config was removed. With the inclusion of a few previous patches
targeting support for preempt enabled kernels, it is now safe to run
with this kernel config option enabled.

Signed-off-by: Prakash Surya <surya1@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #83
2012-08-27 11:54:41 -07:00
Richard Yao
074e72953c Check kernel source directory for SPL
ZFS fails to build when SPL is built into the kernel on unless
--with-spl=/path/to/kernel/sources is specified. We fallback to the
kernel sources directory when SPL is not found elsewhere to resolve
that.

Signed-off-by: Richard Yao <ryao@cs.stonybrook.edu>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closed #896
2012-08-26 13:49:09 -07:00
Prakash Surya
26e08952e6 Support building a zfs-modules-dkms sub package
This commit adds support for building a zfs-modules-dkms sub package
built around Dynamic Kernel Module Support. This is to allow building
packages using the DKMS infrastructure which is intended to ease the
burden of kernel version changes, upgrades, etc.

By default zfs-modules-dkms-* sub package will be built as part of
the 'make rpm' target.  Alternately, you can build only the DKMS
module package using the 'make rpm-dkms' target.

Examples:

    # To build packaged binaries as well as a dkms packages
    $ ./configure && make rpm

    # To build only the packaged binary utilities and dkms packages
    $ ./configure && make rpm-utils rpm-dkms

Note: Only the RHEL 5/6, CHAOS 5, and Fedora distributions are
      supported for building the dkms sub package.

Signed-off-by: Prakash Surya <surya1@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #535
2012-08-08 15:21:01 -07:00
Prakash Surya
5085d55817 Add '--with-spl-timeout' option
When checking for the SPL Module.symvers file, a timeout can now be
passed in which will pause the configure step while it waits for this
file to be generated. By default, the configure behavior is unchanged as
a timeout of 0 is used. If a positive number of seconds is passed,
configure will wait that number of seconds for the Module.symvers file
before moving on.

The main motivation for this change was to support parallel execution of
'./configure && make' for the SPL and ZFS packages in preparation of
supporting DKMS based packages.

Signed-off-by: Prakash Surya <surya1@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2012-08-08 15:20:55 -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
Etienne Dechamps
705741827a When checking for symbol exports, try compiling.
This patch adds a new autoconf function: ZFS_LINUX_TRY_COMPILE_SYMBOL.
This new function does the following:

 - Call LINUX_TRY_COMPILE with the specified parameters.
 - If unsuccessful, return false.
 - If successful and we're configuring with --enable-linux-builtin,
   return true.
 - Else, call CHECK_SYMBOL_EXPORT with the specified parameters and
   return the result.

All calls to CHECK_SYMBOL_EXPORT are converted to
LINUX_TRY_COMPILE_SYMBOL so that the tests work even when configuring
for builtin on a kernel which doesn't have loadable module support, or
hasn't been built yet.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #851
2012-07-26 13:42:57 -07:00