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
Convert zfs_mg_noalloc_threshold to a module parameter and document

The parameter was added as illumos issue 4081 which was committed to
zfsonlinux in ac72fac3eaa569902cad88053167f7d74e7fe7e4.  This patch
documents the parameter and allows for it to be set as a module parameter.

Signed-off-by: Tim Chase <tim@chase2k.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #2483
Illumos 4168, 4169, 4170: ztest, zdb and zhack fixes

4168 ztest assertion failure in dbuf_undirty
4169 verbatim import causes zdb to segfault
4170 zhack leaves pool in ACTIVE state
Reviewed by: Adam Leventhal <ahl@delphix.com>
Reviewed by: Eric Schrock <eric.schrock@delphix.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Approved by: Dan McDonald <danmcd@nexenta.com>

References:
    https://www.illumos.org/issues/4168
    https://www.illumos.org/issues/4169
    https://www.illumos.org/issues/4170
    https://github.com/illumos/illumos-gate/commit/7fdd916

Porting notes:

Of particular interest when troubleshooting corrupted pools, the
commonly-used "zdb -e" operation may perform verbatim imports and
furthermore, it will soon have direct support for verbatim imports via
a new "-V" option.  The 4169 fix eliminates a common segfault case in
which spa_history_log_version() tries to access an un-opened dsl_pool_t.

Ported by: Tim Chase <tim@chase2k.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #2451
Closes #2283
Closes #2467
zdb: Introduce -V for verbatim import

When given a pool name via -e, zdb would attempt an import. If it
failed, then it would attempt a verbatim import. This behavior is
not always desirable so a -V switch is added to zdb to control the
behavior. When specified, a verbatim import is done. Otherwise,
the behavior is as it was previously, except no verbatim import
is done on failure.

Signed-off-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #2372
Fix zil_commit() NULL dereference

Update the current code to ensure inodes are never dirtied if they are
part of a read-only file system or snapshot.  If they do somehow get
dirtied an attempt will make made to write them to disk.  In the case
of snapshots, which don't have a ZIL, this will result in a NULL
dereference in zil_commit().

Signed-off-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #2405
Use Linux kzalloc()/kfree() for superblocks

We store the bdi in the superblock. This is accessed using virt_to_page
in bit_waitqueue(), which does not work on kernel virtual memory. We
switch to kzalloc()/kfree() to fix this.

Signed-off-by: Richard Yao <ryao@gentoo.org>
Revert "Use taskq for dump_bytes()"

This reverts commit 044baf009aac4935eca0f96477eb3c43e95d758a.

Conflicts:
	module/zfs/dmu_send.c
	module/zfs/spa.c
Remove Linux-specific taskq_empty_ent/taskq_init_ent

Signed-off-by: Richard Yao <ryao@gentoo.org>
Do not use taskq_dispatch_delay() in zpl_posix_acl_free()

Signed-off-by: Richard Yao <ryao@gentoo.org>
Revert "3246 ZFS I/O deadman thread"

This reverts commit cc92e9d0c3e67a7e66c844466f85696a087bf60a.

Signed-off-by: Richard Yao <ryao@gentoo.org>

Conflicts:
	cmd/zinject/zinject.c
	include/sys/fm/fs/zfs.h
	include/sys/spa_impl.h
	include/sys/vdev_impl.h
	include/sys/zfs_context.h
	include/sys/zfs_ioctl.h
	include/sys/zio.h
	lib/libzpool/taskq.c
	module/zfs/spa.c
	module/zfs/spa_misc.c
	module/zfs/vdev.c
	module/zfs/vdev_queue.c
	module/zfs/zfs_fm.c
	module/zfs/zio.c
	module/zfs/zio_inject.c
Remove assert

Signed-off-by: Richard Yao <ryao@gentoo.org>