Internally ZFS keeps a small log to facilitate debugging. By default
the log is disabled, to enable it set zfs_dbgmsg_enable=1. The contents
of the log can be accessed by reading the /proc/spl/kstat/zfs/dbgmsg file.
Writing 0 to this proc file clears the log.
$ echo 1 >/sys/module/zfs/parameters/zfs_dbgmsg_enable
$ echo 0 >/proc/spl/kstat/zfs/dbgmsg
$ zpool import tank
$ cat /proc/spl/kstat/zfs/dbgmsg
1 0 0x01 -1 0 2492357525542 2525836565501
timestamp message
1441141408 spa=tank async request task=1
1441141408 txg 70 open pool version 5000; software version 5000/5; ...
1441141409 spa=tank async request task=32
1441141409 txg 72 import pool version 5000; software version 5000/5; ...
1441141414 command: lt-zpool import tank
Note the zfs_dbgmsg() and dprintf() functions are both now mapped to
the same log. As mentioned above the kernel debug log can be accessed
though the /proc/spl/kstat/zfs/dbgmsg kstat. For user space consumers
log messages are immediately written to stdout after applying the
ZFS_DEBUG environment variable.
$ ZFS_DEBUG=on ./cmd/ztest/ztest -V
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ned Bass <bass6@llnl.gov>
Closes#3728
Add the required kernel side infrastructure to parse arbitrary
mount options. This enables us to support temporary mount
options in largely the same way it is handled on other platforms.
See the 'Temporary Mount Point Properties' section of zfs(8)
for complete details.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#985Closes#3351
The misc_deregister() function was changed to a void return type.
Rather than add compatibility code to detect this change simply
ignore the return code on all kernels. It was only used to log
an informational error message of no real value.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
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#3589Closes#3344Closes#3295Closes#3257Closes#3243Closes#3030Closes#2841
Since ZoL allows large blocks to be used by volumes, unlike upstream
illumos, the feature flag must be checked prior to volume creation.
This is critical because unlike filesystems, volumes will create a
object which uses large blocks as part of the create. Therefore, it
cannot be safely checked in zfs_check_settable() after the dataset
can been created.
In addition this patch updates the relevant error messages to use
zfs_nicenum() to print the maximum blocksize.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#3591
Many key internal functions pass system return codes that are safe to
return to userland. In the case of ddi_copyin(9F), an error passes -1
and the documentation states very clearly that drivers should pass
EFAULT to userland when this happens.
http://illumos.org/man/9F/ddi_copyin
This does not happen in the ZFS source code. I believe it should be
changed to pass EFAULT. I caught this when writing man pages for the
libzfs_core API.
Signed-off-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#3575
5008 lock contention (rrw_exit) while running a read only load
Reviewed by: Matthew Ahrens <matthew.ahrens@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Alex Reece <alex.reece@delphix.com>
Reviewed by: Christopher Siden <christopher.siden@delphix.com>
Reviewed by: Richard Yao <ryao@gentoo.org>
Reviewed by: Saso Kiselkov <skiselkov.ml@gmail.com>
Approved by: Garrett D'Amore <garrett@damore.org>
Porting notes:
This patch ported perfectly cleanly to ZoL. During testing 100% cached
small-block reads, extreme contention was noticed on rrl->rr_lock from
rrw_exit() due to the frequent entering and leaving ZPL. Illumos picked
up this patch from FreeBSD and it also helps under Linux.
On a 1-minute 4K cached read test with 10 fio processes pinned to a single
socket on a 4-socket (10 thread per socket) NUMA system, contentions on
rrl->rr_lock were reduced from 508799 to 43085.
Ported-by: Tim Chase <tim@chase2k.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#3555
5946 zfs_ioc_space_snaps must check that firstsnap and lastsnap refer to snapshots
5945 zfs_ioc_send_space must ensure that fromsnap refers to a snapshot
Reviewed by: Steven Hartland <killing@multiplay.co.uk>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Approved by: Gordon Ross <gordon.ross@nexenta.com>
References:
https://www.illumos.org/issues/5946https://www.illumos.org/issues/5945https://github.com/illumos/illumos-gate/commit/24218be
Ported-by: Andriy Gapon <avg@FreeBSD.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#3552
Unit testing at ClusterHQ found that passing an invalid file handle to
zfs_ioc_hold results in a NULL pointer dereference on a system without
assertions:
IP: [<ffffffffa0218aa0>] zfsdev_getminor+0x10/0x20 [zfs]
Call Trace:
[<ffffffffa021b4b0>] zfs_onexit_fd_hold+0x20/0x40 [zfs]
[<ffffffffa0214043>] zfs_ioc_hold+0x93/0xd0 [zfs]
[<ffffffffa0215890>] zfsdev_ioctl+0x200/0x500 [zfs]
An assertion would have caught this had they been enabled, but this is
something that the kernel module should handle without failing. We
resolve this by searching the linked list to ensure that the file
handle's private_data points to a valid zfsdev_state_t.
Signed-off-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Andriy Gapon <avg@FreeBSD.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#3506
Per the documentation for dnode_next_offset in dnode.c, the "txg"
parameter specifies a lower bound on which transaction the dnode can
be found in. We are interested in all dnodes that are removed between
the first and last transaction in the snapshot. It doesn't need to be
created in that snapshot to correspond to a removed file.
In fact, the behavior of zfs diff in the test case exactly matches
this: the transaction that created the data that was deleted in snapshot
"2" was produced before, in snapshot "1", definitely predating the first
transaction in snapshot "2".
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Tim Chase <Tim Chase <tim@onlight.com>
Closes#2081
5765 add support for estimating send stream size with lzc_send_space when source is a bookmark
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Christopher Siden <christopher.siden@delphix.com>
Reviewed by: Steven Hartland <killing@multiplay.co.uk>
Reviewed by: Bayard Bell <buffer.g.overflow@gmail.com>
Approved by: Albert Lee <trisk@nexenta.com>
References:
https://www.illumos.org/issues/5765https://github.com/illumos/illumos-gate/commit/643da460
Porting notes:
* Unused variable 'recordsize' in dmu_send_estimate() dropped
Ported-by: DHE <git@dehacked.net>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#3397
5027 zfs large block support
Reviewed by: Alek Pinchuk <pinchuk.alek@gmail.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Josef 'Jeff' Sipek <josef.sipek@nexenta.com>
Reviewed by: Richard Elling <richard.elling@richardelling.com>
Reviewed by: Saso Kiselkov <skiselkov.ml@gmail.com>
Reviewed by: Brian Behlendorf <behlendorf1@llnl.gov>
Approved by: Dan McDonald <danmcd@omniti.com>
References:
https://www.illumos.org/issues/5027https://github.com/illumos/illumos-gate/commit/b515258
Porting Notes:
* Included in this patch is a tiny ISP2() cleanup in zio_init() from
Illumos 5255.
* Unlike the upstream Illumos commit this patch does not impose an
arbitrary 128K block size limit on volumes. Volumes, like filesystems,
are limited by the zfs_max_recordsize=1M module option.
* By default the maximum record size is limited to 1M by the module
option zfs_max_recordsize. This value may be safely increased up to
16M which is the largest block size supported by the on-disk format.
At the moment, 1M blocks clearly offer a significant performance
improvement but the benefits of going beyond this for the majority
of workloads are less clear.
* The illumos version of this patch increased DMU_MAX_ACCESS to 32M.
This was determined not to be large enough when using 16M blocks
because the zfs_make_xattrdir() function will fail (EFBIG) when
assigning a TX. This was immediately observed under Linux because
all newly created files must have a security xattr created and
that was failing. Therefore, we've set DMU_MAX_ACCESS to 64M.
* On 32-bit platforms a hard limit of 1M is set for blocks due
to the limited virtual address space. We should be able to relax
this one the ABD patches are merged.
Ported-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#354
4951 ZFS administrative commands should use reserved space, not with ENOSPC
Reviewed by: John Kennedy <john.kennedy@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Christopher Siden <christopher.siden@delphix.com>
Reviewed by: Dan McDonald <danmcd@omniti.com>
Approved by: Garrett D'Amore <garrett@damore.org>
References:
https://www.illumos.org/issues/4373https://github.com/illumos/illumos-gate/commit/7d46dc6
Ported by: Brian Behlendorf <behlendorf1@llnl.gov>
3897 zfs filesystem and snapshot limits
Author: Jerry Jelinek <jerry.jelinek@joyent.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Approved by: Christopher Siden <christopher.siden@delphix.com>
References:
https://www.illumos.org/issues/3897https://github.com/illumos/illumos-gate/commit/a2afb61
Porting Notes:
dsl_dataset_snapshot_check(): reduce stack usage using kmem_alloc().
Ported-by: Chris Dunlop <chris@onthe.net.au>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Prevent deadlocks by disabling direct reclaim during all ZPL and ioctl
calls as well as the l2arc and adapt ARC threads.
This obviates the need for MUTEX_FSTRANS so its previous uses and
definition have been eliminated.
Signed-off-by: Tim Chase <tim@chase2k.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#3225
Cleanly destroying or exporting a pool requires that the pool
not be suspended. Therefore, set the POOL_CHECK_SUSPENDED flag
for these ioctls so the utilities will output a descriptive
error message rather than block.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #2878
In the original implementation of the SPL wrappers were provided
for module initialization and cleanup. This was done to abstract
away any compatibility code which might be needed for the SPL.
As it turned out the only significant compatibility issue was that
the default pwd during module load differed under Illumos and Linux.
Since this is such as minor thing and the wrappers complicate the
code they are being retired.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#2985
Several of the nvlist functions may perform allocations larger than
the 32k warning threshold. Convert them to use vmem_alloc() so the
best allocator is used.
Commit efcd79a retired KM_NODEBUG which was used to suppress large
allocation warnings. Concurrently the large allocation warning threshold
was increased from 8k to 32k. The goal was to identify the remaining
locations, such as this one, where the allocation can be larger than
32k. This patch is expected fine tuning resulting for the kmem-rework
changes, see commit 6e9710f.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#3057Closes#3079Closes#3081
By marking DMU transaction processing contexts with PF_FSTRANS
we can revert the KM_PUSHPAGE -> KM_SLEEP changes. This brings
us back in line with upstream. In some cases this means simply
swapping the flags back. For others fnvlist_alloc() was replaced
by nvlist_alloc(..., KM_PUSHPAGE) and must be reverted back to
fnvlist_alloc() which assumes KM_SLEEP.
The one place KM_PUSHPAGE is kept is when allocating ARC buffers
which allows us to dip in to reserved memory. This is again the
same as upstream.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Callers of kmem_alloc() which passed the KM_NODEBUG flag to suppress
the large allocation warning have been replaced by vmem_alloc() as
appropriate. The updated vmem_alloc() call will not print a warning
regardless of the size of the allocation.
A careful reader will notice that not all callers have been changed
to vmem_alloc(). Some have only had the KM_NODEBUG flag removed.
This was possible because the default warning threshold has been
increased to 32k. This is desirable because it minimizes the need
for Linux specific code changes.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Inclusion of SPL compatibility headers was moved out of the public
header sys/types.h to avoid conflicts with external packages. Include a
few compatiblity headers explicitly to cope with that change. Also,
sort some linux-specific inclusions alphabetically.
Signed-off-by: Ned Bass <bass6@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#2898
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>
Reviewed by Matthew Ahrens <mahrens@delphix.com>
Reviewed by Saso Kiselkov <skiselkov.ml@gmail.com>
Approved by: Christopher Siden <christopher.siden@delphix.com>
References:
https://github.com/illumos/illumos-gate/commit/b8289d2https://www.illumos.org/issues/3756
Porting notes:
The static function zfs_prop_activate_feature() was removed because
this change removes the only caller. The function was not removed
from Illumos but instead left as dead code. However, to keep gcc
happy it was removed from Linux and may be easily restored if needed.
Ported by: DHE <git@dehacked.net>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#1540
4757 ZFS embedded-data block pointers ("zero block compression")
4913 zfs release should not be subject to space checks
Reviewed by: Adam Leventhal <ahl@delphix.com>
Reviewed by: Max Grossman <max.grossman@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Christopher Siden <christopher.siden@delphix.com>
Reviewed by: Dan McDonald <danmcd@omniti.com>
Approved by: Dan McDonald <danmcd@omniti.com>
References:
https://www.illumos.org/issues/4757https://www.illumos.org/issues/4913https://github.com/illumos/illumos-gate/commit/5d7b4d4
Porting notes:
For compatibility with the fastpath code the zio_done() function
needed to be updated. Because embedded-data block pointers do
not require DVAs to be allocated the associated vdevs will not
be marked and therefore should not be unmarked.
Ported by: Tim Chase <tim@chase2k.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#2544
4171 clean up spa_feature_*() interfaces
4172 implement extensible_dataset feature for use by other zpool features
Reviewed by: Max Grossman <max.grossman@delphix.com>
Reviewed by: Christopher Siden <christopher.siden@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Jerry Jelinek <jerry.jelinek@joyent.com>
Approved by: Garrett D'Amore <garrett@damore.org>a
References:
https://www.illumos.org/issues/4171https://www.illumos.org/issues/4172https://github.com/illumos/illumos-gate/commit/2acef22
Ported-by: Tim Chase <tim@chase2k.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#2528
Restructure the zfsdev_state_list to allow for lock-free reading by
converting to a simple singly-linked list from which items are never
deleted and over which only forward iterations are performed. It depends
on, among other things, the atomicity of accessing the zs_minor integer
and zs_next pointer.
This fixes a lock inversion in which the zfsdev_state_lock is used by
both the sync task (txg_sync) and indirectly by any user program which
uses /dev/zfs; the zfsdev_release method uses the same lock and then
blocks on the sync task.
The most typical failure scenerio occurs when the sync task is cleaning
up a user hold while various concurrent "zfs" commands are in progress.
Neither Illumos nor Solaris are affected by this issue because they use
DDI interface which provides lock-free reading of device state via the
ddi_get_soft_state() function.
Signed-off-by: Tim Chase <tim@chase2k.com>
Signed-off-by: Chunwei Chen <tuxoko@gmail.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#2301
Due to an asymmetry in the kmem accounting a memory leak was being
reported when it was only an accounting issue. All memory allocated
with kmem_alloc() must be released with kmem_free() or it will not
be properly accounted for.
In this case the code used strfree() to release the memory allocated
by kmem_alloc(). Presumably this was done because the size of the
memory region wasn't available when the memory needed to be freed.
To resolve this issue the code has been updated to use strdup() instead
of kmem_alloc() to allocate the memory. Like strfree(), strdup() is
not integrated with the memory accounting. This means we can use
strfree() to release it like Illumos.
SPL: kmem leaked 10/4368729 bytes
address size data func:line
ffff880067e9aa40 10 ZZZZZZZZZZ zfsdev_ioctl:5655
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Tim Chase <tim@chase2k.com>
Signed-off-by: Chunwei Chen <tuxoko@gmail.com>
Closes#2262
Due to the very poorly chosen argument name 'cleanup_fd' it was
completely unclear that this file descriptor is used to track the
current cursor location. When the file descriptor is created by
opening ZFS_DEV a private cursor is created in the kernel for the
returned file descriptor. Subsequent calls to zpool_events_next()
and zpool_events_seek() then require the file descriptor as an
argument to reposition the cursor. When the file descriptor is
closed the kernel state tracking the cursor is destroyed.
This patch contains no functional change, it just changes a
few variable names and clarifies the documentation.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Chris Dunlap <cdunlap@llnl.gov>
Issue #2
The ZFS_IOC_EVENTS_SEEK ioctl was added to allow user space callers
to seek around the zevent file descriptor by EID. When a specific
EID is passed and it exists the cursor will be positioned there.
If the EID is no longer cached by the kernel ENOENT is returned.
The caller may also pass ZEVENT_SEEK_START or ZEVENT_SEEK_END to seek
to those respective locations.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Chris Dunlap <cdunlap@llnl.gov>
Issue #2
Remove the redundant call to zfs_unmount_snap() which was being
done after char array was freed,
This fixes an upstream regression that was introduced in commit
zfsonlinux/zfs@d09f25dc66, which
ported the Illumos 3744 changes.
Signed-off-by: Andrey Vesnovaty <andrey.vesnovaty@gmail.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Richard Yao <ryao@gentoo.org>
Closes#2156
Move the libzfs_fini() after the zpool_log_history() call so the
ZPOOL_HIST_CMD entry can get written.
Fix the handling of saved_poolname in zfsdev_ioctl()
which was broken as part of the stack-reduction work in
a168788053.
Since ZoL destroys the TSD data in which the previously successful
ioctl()'s pool name is stored following every vop, the ZFS_IOC_LOG_HISTORY
ioctl has a very important restriction: it can only successfully write
a long entry following a successful ioctl() if no intervening vops have
been performed. Some of zfs subcommands do perform intervening vops and
to do the logging themselves. At the moment, the "create" and "clone"
subcommands have been modified appropriately.
Signed-off-by: Tim Chase <tim@chase2k.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#1998
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
In order to minimize any future disruption caused by the addition
and removal /dev/zfs ioctls this patch makes the following changes.
1) Sync ZoL's ioctl ordering such that it matches Illumos. For
historic reasons the ZFS_IOC_DESTROY_SNAPS and ZFS_IOC_POOL_REGUID
ioctls were out of order.
2) Move Linux and FreeBSD specific ioctls in to their own reserved
ranges. This allows us to preserve the existing ordering when
new ioctls are added by either Illumos or FreeBSD. When an
ioctl is no longer needed it should be retired in place.
This change alters the ZFS user/kernel ABI so make sure you rebuild
both your user and kernel modules. However, it should allow for a
much stabler interface going forward.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ned Bass <bass6@llnl.gov>
Closes#1973
Early versions of ZFS coordinated the creation and destruction
of device minors from userspace. This was inherently racy and
in late 2009 these ioctl()s were removed leaving everything up
to the kernel. This significantly simplified the code.
However, we never picked up these changes in ZoL since we'd
already significantly adjusted this code for Linux. This patch
aims to rectify that by finally removing ZFC_IOC_*_MINOR ioctl()s
and moving all the functionality down in to the kernel. Since
this cleanup will change the kernel/user ABI it's being done
in the same tag as the previous libzfs_core ABI changes. This
will minimize, but not eliminate, the disruption to end users.
Once merged ZoL, Illumos, and FreeBSD will basically be back
in sync in regards to handling ZVOLs in the common code. While
each platform must have its own custom zvol.c implemenation the
interfaces provided are consistent.
NOTES:
1) This patch introduces one subtle change in behavior which
could not be easily avoided. Prior to this change callers
of 'zfs create -V ...' were guaranteed that upon exit the
/dev/zvol/ block device link would be created or an error
returned. That's no longer the case. The utilities will no
longer block waiting for the symlink to be created. Callers
are now responsible for blocking, this is why a 'udev_wait'
call was added to the 'label' function in scripts/common.sh.
2) The read-only behavior of a ZVOL now solely depends on if
the ZVOL_RDONLY bit is set in zv->zv_flags. The redundant
policy setting in the gendisk structure was removed. This
both simplifies the code and allows us to safely leverage
set_disk_ro() to issue a KOBJ_CHANGE uevent. See the
comment in the code for futher details on this.
3) Because __zvol_create_minor() and zvol_alloc() may now be
called in a sync task they must use KM_PUSHPAGE.
References:
illumos/illumos-gate@681d9761e8
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ned Bass <bass6@llnl.gov>
Signed-off-by: Tim Chase <tim@chase2k.com>
Closes#1969
Use the standard Linux MODULE_VERSION macro to expose the installed
zavl, znvpair, zunicode, zcommon, zfs, and zpios module versions.
This will also automatically add a checksum of the .c files and
headers in "srcversion". See:
/sys/module/zavl/version
/sys/module/zavl/srcversion
/sys/module/znvpair/version
/sys/module/znvpair/srcversion
/sys/module/zunicode/version
/sys/module/zunicode/srcversion
/sys/module/zcommon/version
/sys/module/zcommon/srcversion
/sys/module/zfs/version
/sys/module/zfs/srcversion
/sys/module/zpios/version
/sys/module/zpios/srcversion
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#1923
Under Linux this restriction does not apply because we have access
to all the required devices.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#1631
During pool import stack overflows may still occur due to the
potentially deep recursion of traverse_visitbp(). This is most
likely to occur when additional layers are added to the block
device stack such as DM multipath. To minimize the stack usage
for this call path the following changes were made:
1) Added the keywork 'noinline' to the vdev_*_map_alloc() functions
to prevent them from being inlined by gcc. This reduced the
stack usage of vdev_raidz_io_start() from 208 to 128 bytes, and
vdev_mirror_io_start() from 144 to 128 bytes.
2) The 'saved_poolname' charater array in zfsdev_ioctl() was moved
from the stack to the heap. This reduced the stack usage of
zfsdev_ioctl() from 368 to 112 bytes.
3) The major saving came from slimming down traverse_visitbp() from
from 224 to 144 bytes. Since this function is called recursively
the 80 bytes saved per invokation adds up. The following changes
were made:
a) The 'hard' local variable was replaced by a TD_HARD() macro.
b) The 'pd' local variable was replaced by 'td->td_pfd' references.
c) The zbookmark_t was moved to the heap. This does cost us an
additional memory allocation per recursion by that cost should
still be minimal. The cost could be further reduced by adding
a dedicated zbookmark_t slab cache.
d) The variable declarations in 'if (BP_GET_LEVEL()) { }' were
restructured to use the minimum amount of stack. This includes
removing the 'cbp' local variable.
Overall for the offending use case roughly 1584 of total stack space
has been saved. This is enough to avoid overflowing the stack on
stock kernels with 8k stacks. See #1778 for additional details.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ned Bass <bass6@llnl.gov>
Closes#1778
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
3996 want a libzfs_core API to rollback to latest snapshot
Reviewed by: Christopher Siden <christopher.siden@delphix.com>
Reviewed by: Adam Leventhal <ahl@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Andy Stormont <andyjstormont@gmail.com>
Approved by: Richard Lowe <richlowe@richlowe.net>
References:
https://www.illumos.org/issues/3996illumos/illumos-gate@a7027df17f
Ported-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #1775
3973 zfs_ioc_rename alters passed in zc->zc_name
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Approved by: Christopher Siden <christopher.siden@delphix.com>
References:
https://www.illumos.org/issues/3973illumos/illumos-gate@a0c1127b14
Ported-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #1775
3875 panic in zfs_root() after failed rollback
Reviewed by: Jerry Jelinek <jerry.jelinek@joyent.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Approved by: Gordon Ross <gwr@nexenta.com>
References:
https://www.illumos.org/issues/3875illumos/illumos-gate@91948b51b8
Ported-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #1775
3740 Poor ZFS send / receive performance due to snapshot
hold / release processing
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Approved by: Christopher Siden <christopher.siden@delphix.com>
References:
https://www.illumos.org/issues/3740illumos/illumos-gate@a7a845e4bf
Ported-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #1775
Porting notes:
1. 13fe019870 introduced a merge conflict
in dsl_dataset_user_release_tmp where some variables were moved
outside of the preprocessor directive.
2. dea9dfefdd747534b3846845629d2200f0616dad made the previous merge
conflict worse by switching KM_SLEEP to KM_PUSHPAGE. This is notable
because this commit refactors the code, adding a new KM_SLEEP
allocation. It is not clear to me whether this should be converted
to KM_PUSHPAGE.
3. We had a merge conflict in libzfs_sendrecv.c because of copyright
notices.
4. Several small C99 compatibility fixed were made.
3744 zfs shouldn't ignore errors unmounting snapshots
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Approved by: Christopher Siden <christopher.siden@delphix.com>
References:
https://www.illumos.org/issues/3744illumos/illumos-gate@fc7a6e3fef
Ported-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #1775
Porting notes:
1. There is no clear way to distinguish between a failure when we
tried to unmount the snapdir of a zvol (which does not exist)
and the failure when we try to unmount a snapdir of a dataset,
so the changes to zfs_unmount_snap() were dropped in favor of
an altered Linux function that unconditionally returns 0.
3742 zfs comments need cleaner, more consistent style
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Eric Schrock <eric.schrock@delphix.com>
Approved by: Christopher Siden <christopher.siden@delphix.com>
References:
https://www.illumos.org/issues/3742illumos/illumos-gate@f717074149
Ported-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #1775
Porting notes:
1. The change to zfs_vfsops.c was dropped because it involves
zfs_mount_label_policy, which does not exist in the Linux port.
3598 want to dtrace when errors are generated in zfs
Reviewed by: Dan Kimmel <dan.kimmel@delphix.com>
Reviewed by: Adam Leventhal <ahl@delphix.com>
Reviewed by: Christopher Siden <christopher.siden@delphix.com>
Approved by: Garrett D'Amore <garrett@damore.org>
References:
https://www.illumos.org/issues/3598illumos/illumos-gate@be6fd75a69
Ported-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #1775
Porting notes:
1. include/sys/zfs_context.h has been modified to render some new
macros inert until dtrace is available on Linux.
2. Linux-specific changes have been adapted to use SET_ERROR().
3. I'm NOT happy about this change. It does nothing but ugly
up the code under Linux. Unfortunately we need to take it to
avoid more merge conflicts in the future. -Brian
Modifying the length of a string returned by strdup() is incorrect
because strfree() is allowed to use strlen() to determine which slab
cache was used to do the allocation.
Signed-off-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #1775
Some ZFS errors such as certain snapshot failures can occur in
the sync task context. Because they may require additional memory
allocations, the initial nvlist must be allocated with KM_PUSHPAGE.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #1746
Issue #1737
