Commit Graph

10 Commits

Author SHA1 Message Date
Brian Behlendorf
bd0d24e09b
Linux 5.5 compat: blkg_tryget()
Commit https://github.com/torvalds/linux/commit/9e8d42a0f accidentally
converted the static inline function blkg_tryget() to GPL-only for
kernels built with CONFIG_PREEMPT_RCU=y and CONFIG_BLK_CGROUP=y.

Resolve the build issue by providing our own equivalent functionality
when needed which uses rcu_read_lock_sched() internally as before.

Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #9745
Closes #10072
2020-02-28 08:58:39 -08:00
Brian Behlendorf
a25861dcae
ZTS: Fix zpool_reopen_001_pos
Update the vdev_disk_open() retry logic to use a specified number
of milliseconds to be more robust.  Additionally, on failure log
both the time waited and requested timeout to the internal log.

The default maximum allowed open retry time has been increased
from 500ms to 1000ms.

Reviewed-by: Kjeld Schouten <kjeld@schouten-lebbing.nl>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #9680
2019-12-09 11:09:14 -08:00
Brian Behlendorf
9e17e6f254
Remove zfs_vdev_elevator module option
As described in commit f81d5ef6 the zfs_vdev_elevator module
option is being removed.  Users who require this functionality
should update their systems to set the disk scheduler using a
udev rule.

Reviewed-by: Richard Laager <rlaager@wiktel.com>
Reviewed-by: loli10K <ezomori.nozomu@gmail.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #8664
Closes #9417
Closes #9609
2019-11-27 10:35:49 -08:00
Matthew Macy
da92d5cbb3 Add zfs_file_* interface, remove vnodes
Provide a common zfs_file_* interface which can be implemented on all 
platforms to perform normal file access from either the kernel module
or the libzpool library.

This allows all non-portable vnode_t usage in the common code to be 
replaced by the new portable zfs_file_t.  The associated vnode and
kobj compatibility functions, types, and macros have been removed
from the SPL.  Moving forward, vnodes should only be used in platform
specific code when provided by the native operating system.

Reviewed-by: Sean Eric Fagan <sef@ixsystems.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Igor Kozhukhov <igor@dilos.org>
Reviewed-by: Jorgen Lundman <lundman@lundman.net>
Signed-off-by: Matt Macy <mmacy@FreeBSD.org>
Closes #9556
2019-11-21 09:32:57 -08:00
loli10K
7ba964cc3f Prevent NULL pointer dereference in blkg_tryget() on EL8 kernels
blkg_tryget() as shipped in EL8 kernels does not seem to handle NULL
@blkg as input; this is different from its mainline counterpart where
NULL is accepted.  To prevent dereferencing a NULL pointer when dealing
with block devices which do not set a root_blkg on the request queue
perform the NULL check in vdev_bio_associate_blkg().

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Kjeld Schouten <kjeld@schouten-lebbing.nl>
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Signed-off-by: loli10K <ezomori.nozomu@gmail.com>
Closes #9546 
Closes #9577
2019-11-13 10:19:06 -08:00
Brian Behlendorf
066e825221
Linux compat: Minimum kernel version 3.10
Increase the minimum supported kernel version from 2.6.32 to 3.10.
This removes support for the following Linux enterprise distributions.

    Distribution     | Kernel | End of Life
    ---------------- | ------ | -------------
    Ubuntu 12.04 LTS | 3.2    | Apr 28, 2017
    SLES 11          | 3.0    | Mar 32, 2019
    RHEL / CentOS 6  | 2.6.32 | Nov 30, 2020

The following changes were made as part of removing support.

* Updated `configure` to enforce a minimum kernel version as
  specified in the META file (Linux-Minimum: 3.10).

    configure: error:
        *** Cannot build against kernel version 2.6.32.
        *** The minimum supported kernel version is 3.10.

* Removed all `configure` kABI checks and matching C code for
  interfaces which solely predate the Linux 3.10 kernel.

* Updated all `configure` kABI checks to fail when an interface is
  missing which was in the 3.10 kernel up to the latest 5.1 kernel.
  Removed the HAVE_* preprocessor defines for these checks and
  updated the code to unconditionally use the verified interface.

* Inverted the detection logic in several kABI checks to match
  the new interface as it appears in 3.10 and newer and not the
  legacy interface.

* Consolidated the following checks in to individual files. Due
  the large number of changes in the checks it made sense to handle
  this now.  It would be desirable to group other related checks in
  the same fashion, but this as left as future work.

  - config/kernel-blkdev.m4 - Block device kABI checks
  - config/kernel-blk-queue.m4 - Block queue kABI checks
  - config/kernel-bio.m4 - Bio interface kABI checks

* Removed the kABI checks for sops->nr_cached_objects() and
  sops->free_cached_objects().  These interfaces are currently unused.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #9566
2019-11-12 08:59:06 -08:00
Matthew Macy
e4f5fa1229 Fix strdup conflict on other platforms
In the FreeBSD kernel the strdup signature is:

```
char	*strdup(const char *__restrict, struct malloc_type *);
```

It's unfortunate that the developers have chosen to change
the signature of libc functions - but it's what I have to
deal with.

Reviewed-by: Jorgen Lundman <lundman@lundman.net>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Matt Macy <mmacy@FreeBSD.org>
Closes #9433
2019-10-10 09:47:06 -07:00
Brian Behlendorf
f81d5ef686
Add warning for zfs_vdev_elevator option removal
Originally the zfs_vdev_elevator module option was added as a
convenience so the requested elevator would be automatically set
on the underlying block devices.  At the time this was simple
because the kernel provided an API function which did exactly this.

This API was then removed in the Linux 4.12 kernel which prompted
us to add compatibly code to set the elevator via a usermodehelper.
While well intentioned this introduced a bug which could cause a
system hang, that issue was subsequently fixed by commit 2a0d4188.

In order to avoid future bugs in this area, and to simplify the code,
this functionality is being deprecated.  A console warning has been
added to notify any existing consumers and the documentation updated
accordingly.  This option will remain for the lifetime of the 0.8.x
series for compatibility but if planned to be phased out of master.

Reviewed-by: Richard Laager <rlaager@wiktel.com>
Reviewed-by: loli10K <ezomori.nozomu@gmail.com>
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #8664
Closes #9317
2019-09-25 09:23:29 -07:00
loli10K
2a0d41889e Scrubbing root pools may deadlock on kernels without elevator_change() (#9321)
Originally the zfs_vdev_elevator module option was added as a
convenience so the requested elevator would be automatically set
on the underlying block devices. At the time this was simple
because the kernel provided an API function which did exactly this.

This API was then removed in the Linux 4.12 kernel which prompted
us to add compatibly code to set the elevator via a usermodehelper.

Unfortunately changing the evelator via usermodehelper requires reading
some userland binaries, most notably modprobe(8) or sh(1), from a zfs
dataset on systems with root-on-zfs. This can deadlock the system if
used during the following call path because it may need, if the data
is not already cached in the ARC, reading directly from disk while
holding the spa config lock as a writer:

  zfs_ioc_pool_scan()
    -> spa_scan()
      -> spa_scan()
        -> vdev_reopen()
          -> vdev_elevator_switch()
            -> call_usermodehelper()

While the usermodehelper waits sh(1), modprobe(8) is blocked in the
ZIO pipeline trying to read from disk:

  INFO: task modprobe:2650 blocked for more than 10 seconds.
       Tainted: P           OE     5.2.14
  modprobe        D    0  2650    206 0x00000000
  Call Trace:
   ? __schedule+0x244/0x5f0
   schedule+0x2f/0xa0
   cv_wait_common+0x156/0x290 [spl]
   ? do_wait_intr_irq+0xb0/0xb0
   spa_config_enter+0x13b/0x1e0 [zfs]
   zio_vdev_io_start+0x51d/0x590 [zfs]
   ? tsd_get_by_thread+0x3b/0x80 [spl]
   zio_nowait+0x142/0x2f0 [zfs]
   arc_read+0xb2d/0x19d0 [zfs]
   ...
   zpl_iter_read+0xfa/0x170 [zfs]
   new_sync_read+0x124/0x1b0
   vfs_read+0x91/0x140
   ksys_read+0x59/0xd0
   do_syscall_64+0x4f/0x130
   entry_SYSCALL_64_after_hwframe+0x44/0xa9

This commit changes how we use the usermodehelper functionality from
synchronous (UMH_WAIT_PROC) to asynchronous (UMH_NO_WAIT) which prevents
scrubs, and other vdev_elevator_switch() consumers, from triggering the
aforementioned issue.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: loli10K <ezomori.nozomu@gmail.com>
Issue #8664 
Closes #9321
2019-09-13 18:09:59 -07:00
Matthew Macy
bced7e3aaa OpenZFS restructuring - move platform specific sources
Move platform specific Linux source under module/os/linux/
and update the build system accordingly.  Additional code
restructuring will follow to make the common code fully
portable.
    
Reviewed-by: Jorgen Lundman <lundman@lundman.net>
Reviewed-by: Igor Kozhukhov <igor@dilos.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Matthew Macy <mmacy@FreeBSD.org>
Closes #9206
2019-09-06 11:26:26 -07:00