mirror_zfs/include/os
Brian Behlendorf 6152014d1a
Linux 4.18.0-257.el8 compat: blk_alloc_queue()
The CentOS stream 4.18.0-257 kernel appears to have backported
the Linux 5.9 change to make_request_fn and the associated API.
To maintain weak modules compatibility the original symbol was
retained and the new interface blk_alloc_queue_rh() was added.

Unfortunately, blk_alloc_queue() was replaced in the blkdev.h
header by blk_alloc_queue_bh() so there doesn't seem to be a way
to build new kmods against the old interfces.  Even though they
appear to still be available for weak module binding.

To accommodate this a configure check is added for the new _rh()
variant of the function and used if available.  If compatibility
code gets added to the kernel for the original blk_alloc_queue()
interface this should be fine.  OpenZFS will simply continue to
prefer the new interface and only fallback to blk_alloc_queue()
when blk_alloc_queue_rh() isn't available.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #11374
2020-12-21 10:11:56 -08:00
..
freebsd FreeBSD: Implement sysctl for fletcher4 impl 2020-12-11 10:29:01 -08:00
linux Linux 4.18.0-257.el8 compat: blk_alloc_queue() 2020-12-21 10:11:56 -08:00
Makefile.am Add FreeBSD support to OpenZFS 2020-04-14 11:36:28 -07:00