Only automatically mount a clone when 'canmount == on'.

According to the man page, "When the noauto option is set, a dataset
can only be mounted and unmounted explicitly. The dataset is not
mounted automatically when the dataset is created or imported ...."

When cloning a dataset the canmount property was not being honored.
This patch adds the required check to achieve the behavior described
in the man page.

Signed-off-by: Turbo Fredriksson <turbo@bayour.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #2241
Document the fact that ashift is vdev specific, not a pool global.

Users need to be aware that when adding devices to an existing pool
they may need to override automatically detected ashift value.
This will all depend on the exact hardware they are using.

Signed-off-by: Turbo Fredriksson <turbo@bayour.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes: #2024
Man page updates for 'zfs share'

* Remove the references to share(1M), unshare(1M) and dfstab(4)
  since they are not applicable to Linux.
* Add the exact exportfs command line used when setting sharenfs=on.

Signed-off-by: Turbo Fredriksson <turbo@bayour.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue: #1641
Expand the description of scan-related and other parameters.

Document that the scan-related parameters are, in fact, applicable only
to scrub and/or resilver operations as appropriate.

Expand a few of the prefetch-related descriptions.

Add clarification to other module parameters.

Signed-off-by: Tim Chase <tim@chase2k.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #2361
Document the -X and -T options to 'zpool import'

These options have existed for a long time but have historically
been undocumented because they are not guaranteed to be safe.  They
should only be used as a last resort when attempting to recover a
damaged pool.

Signed-off-by: Turbo Fredriksson <turbo@bayour.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #1130
Set LANG to a reasonable default (C)

Set LANG=C before calling 'rpmbuild' to avoid rpmbuild failing on
the translated date string in the changelog.

Signed-off-by: Turbo Fredriksson <turbo@bayour.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes: zfsonlinux/spl#306
Revert "Fix __zio_execute() asynchronous dispatch"

This reverts commit 91579709fccd3e55a21970742b66c388fb1403db which
limited the asynchronous dispatch to kernel space.  We want to do
this for two reasons:

1) While we have slightly more headroom in user space excessively
   deep stacks have been observed while running ztest, see #2293.

2) Removing this conditional makes the pipeline behave consistently
   regardless of if it's executing in kernel space or user space.
   This way we're more likely to uncover subtle issues with ztest.

Signed-off-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #2384
Accept udev and dracut paths specified by ./configure

There are two common locations where udev and dracut components are
commonly installed.  When building packages using the 'make rpm|deb'
targets check those common locations and pass them to rpmbuild.  For
non-standard configurations these values can be provided by the
the following configure options:

  --with-udevdir=DIR      install udev helpers [default=check]
  --with-udevruledir=DIR  install udev rules [[UDEVDIR/rules.d]]
  --with-dracutdir=DIR    install dracut helpers [default=check]

When rebuilding using the source packages the per-distribution
default values specified in the spec file will be used.  This is
the preferred way to build packages for a distribution but the
ability to override the defaults is provided as a convenience.

Signed-off-by: Turbo Fredriksson <turbo@bayour.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #2310
Closes #1680
Fix zfs.spec.in defaults

Commit 2ee4e7da accidentally introduced two issues which only occur
when rebuilding the ZFS source rpm outside the ZFS build system.

1) The _dracutdir, _udevdir, and _udevruledir macros must be checked
   using the 'undefined' keyword.  This was just overlooked in the
   patch review and does not cause a failure when using 'make pkg'
   because the values are provided by the make target.

2) The default _udevruledir path included a typo.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #2310
Tag zfs-0.6.3

META file and release log updated.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Fix man zpool property feature_guid

The property name gets mangled with the explanation due to the property
length.  Fixed by putting the explanation on the next line.

Before:
  unsupported@feature_Info rmation about unsupported features that are
  enabled on the pool. See zpool-features(5) for details.

After:
  unsupported@feature_guid
  Information about unsupported features that are enabled on the pool. See
  zpool-features(5) for details.

Signed-off-by: SenH <sen@senhaerens.be>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #2419
Add information about the -o option to zpool replace

Users need to be aware that when replacing devices in an existing
pool they may need to override automatically detected ashift value.
This will all depend on the exact hardware they are using.

Signed-off-by: Turbo Fredriksson <turbo@bayour.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #2024
Improve differing sector size error

When adding or replacing a vdev with a different sector size the
error message should be more useful.  In addition to describing
the problem provide a hint that the '-o ashift' option can be
used to override the optimal default value.

Since using a non-optimal value may incur a significant performance
penalty we should issue this error.  But there a numerous reasons
why a administrator may wish to do this anyway.

Signed-off-by: Niklas Edmundsson <ZNikke@github>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #2421
Comment the lack of real_LZ4_uncompress()

Added several comments regarding the removal of real_LZ4_uncompress()
which exists in the reference implementation but has been removed here
since it's not used.

Signed-off-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Tim Chase <tim@chase2k.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Illumos #4936 fix potential overflow in lz4

4936 lz4 could theoretically overflow a pointer with a certain input
Reviewed by: Saso Kiselkov <skiselkov.ml@gmail.com>
Reviewed by: Keith Wesolowski <keith.wesolowski@joyent.com>
Approved by: Gordon Ross <gordon.ross@nexenta.com>
Ported by: Tim Chase <tim@chase2k.com>

References:
  https://illumos.org/issues/4936
  https://github.com/illumos/illumos-gate/commit/58d0718

Porting notes:

This fixes the widely-reported "20-year-old vulnerability" in
LZO/LZ4 implementations which inherited said bug from the reference
implementation.

Signed-off-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Tim Chase <tim@chase2k.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #2429
Return default value on numeric properties failing the "head check.

Updates 962d52421236fc9cd61d59b4f18cff3276077da9.

The referenced fix to get_numeric_property() caused numeric property
lookups to consider the type of the parent (head) dataset when checking
validity but there are some cases in the caller expects to see the
property's default value even when the lookup is invalid.

One case in which this is true is change_one() which is part of the
renaming infrastructure.  It may look up "zoned" on a snapshot of a volume
which is not valid but it expects to see the default value of false.

There may be other, yet unidentified cases in which zfs_prop_get_int()
is used on technically invalid properties but which expect the property's
default value to be returned.

Signed-off-by: Tim Chase <tim@chase2k.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Turbo Fredriksson <turbo@bayour.com>
Closes #2320
Document the optional "device" argument for "zpool split"

Most ZFS implementations seemed to have missed this bit of documentation.
The additional text is based on FreeBSD's man page.

Signed-off-by: Tim Chase <tim@chase2k.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #2416
Fix comment spelling errors.

Signed-off-by: Garrison Jensen <garrison.jensen@gmail.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #2402
Preserve asize when last mirror child promoted to top-level vdev

If the smaller of 2 different sized child vdev's of a mirrored vdev is
detached, and the pool has the autoexpand property set to off, as the
remaining larger vdev is promoted to a top level vdev it fails to retain
the asize of the original top level mirror vdev and therefore partially
autoexpands.

This partially autoexpanded state leaves the new vdev too large to
re-mirror by adding the smaller vdev back in, and the pool fails to
utilize the space until next imported.

If the autoexpand property is set to on, the child vdev grows
in size after it has been promoted to a top level vdev as expected.

This commit causes the remaining child mirror to retain the asize of its
old parent mirror vdev if the autoexpand property is set to off,
this allows the smaller vdev to be re-added if required the vdev
can then be told to expand if required by the usual using zpool online -e.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Andrew Barnes <barnes333@gmail.com>
Signed-off-by: George Wilson <george.wilson@delphix.com>
Closes #1208
Illumos #3641 compressed block histograms with zdb

This patch is a zdb extension of the '-b' option, producing a histogram
of the physical compressed block sizes per DMU object type on disk. The
'-bbbb' option to zdb will uncover this new feature; here's an example
usage on a new pool and snippet of the output it generates:

    # zpool create tank /dev/vd{b,c,d}
    # dd bs=1k  if=/dev/urandom of=/tank/1kfile  count=1
    # dd bs=3k  if=/dev/urandom of=/tank/3kfile  count=1
    # dd bs=64k if=/dev/urandom of=/tank/64kfile count=1
    # zdb -bbbb tank
    ...
         3  68.0K   68.0K   68.0K   22.7K    1.00    34.26  ZFS plain file
    psize (in 512-byte sectors): number of blocks
                              2:      1 *
                              3:      0
                              4:      0
                              5:      0
                              6:      1 *
                              7:      0
    ...
                            127:      0
                            128:      1 *
    ...

The blocks are also broken down by their indirection level. Expanding on
the above example:

    # zfs set recordsize=1k tank
    # dd bs=1k if=/dev/urandom of=/tank/2x1kfile count=2
    # zdb -bbbb tank
    ...
         1    16K      1K      2K      2K   16.00     1.02      L1 ZFS plain file
    psize (in 512-byte sectors): number of blocks
                              2:      1 *
         5  70.0K   70.0K   70.0K   14.0K    1.00    35.71      L0 ZFS plain file
    psize (in 512-byte sectors): number of blocks
                              2:      3 ***
                              3:      0
                              4:      0
                              5:      0
                              6:      1 *
                              7:      0
    ...
                            127:      0
                            128:      1 *
         6  86.0K   71.0K   72.0K   12.0K    1.21    36.73  ZFS plain file
    psize (in 512-byte sectors): number of blocks
                              2:      4 ****
                              3:      0
                              4:      0
                              5:      0
                              6:      1 *
                              7:      0
    ...
                            127:      0
                            128:      1 *
    ...

There's now a single 1K L1 block which is the indirect block needed for
the '2x1kfile' file just created, as well as two more 1K L0 blocks from
the same file.

This can be used to get a distribution of the block sizes used within
the pool, on a per object type basis.

References:
  https://illumos.org/issues/3641
  https://github.com/illumos/illumos-gate/commit/490d05b

Ported by: Tim Chase <tim@chase2k.com>
Signed-off-by: Prakash Surya <surya1@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Boris Protopopov <boris.protopopov@me.com>
Closes #2456