src/sys/dev/xen/blkback, branch main

sys/xen: Use __printflike() instead of format(printf)

2025-12-28T21:16:40+00:00

The __printflike macro sets the format to freebsd_kprintf which recent
clang understands and warns about. Fixes the following error:
`passing 'printf' format string where 'freebsd_kprintf' format string is expected [-Werror,-Wformat]`

MFC after:	1 week

xen/blk{front,back}: fix usage of sector sizes different than 512b

2024-10-08T07:29:13+00:00

The units of the size reported in the 'sectors' xenbus node is always 512b,
regardless of the value of the 'sector-size' node.  The sector offsets in
the ring requests are also always based on 512b sectors, regardless of the
'sector-size' reported in xenbus.

Fix both blkfront and blkback to assume 512b sectors in the required fields.

The blkif.h public header has been recently updated in upstream Xen repository
to fix the regressions in the specification introduced by later modifications,
and clarify the base units of xenstore and shared ring fields.

PR: 280884
Reported by: Christian Kujau
MFC after: 1 week
Sponsored by: Cloud Software Group
Reviewed by: markj
Differential revision: https://reviews.freebsd.org/D46756

xen/dev: switch to DEVMETHOD_END

2023-11-28T12:31:47+00:00

Switch to the preferred end of the device method table.  These hadn't
been updated previously.

Reviewed by: royger

sys: Remove $FreeBSD$: one-line .c pattern

2023-08-16T17:54:36+00:00

Remove /^[\s*]*__FBSDID\("\$FreeBSD\$"\);?\s*\n/

spdx: The BSD-2-Clause-FreeBSD identifier is obsolete, drop -FreeBSD

2023-05-12T16:44:03+00:00

The SPDX folks have obsoleted the BSD-2-Clause-FreeBSD identifier. Catch
up to that fact and revert to their recommended match of BSD-2-Clause.

Discussed with:		pfg
MFC After:		3 days
Sponsored by:		Netflix

Fix unused variable warning in xen's blkback.c

2022-07-26T17:59:55+00:00

With clang 15, the following -Werror warning is produced:

    sys/dev/xen/blkback/blkback.c:1561:12: error: variable 'req_seg_idx' set but not used [-Werror,-Wunused-but-set-variable]
                    u_int                    req_seg_idx;
                                             ^

The 'req_seg_idx' variable was used in the for loop later in the
xbb_dispatch_io() function, but refactoring in 112cacaee408 got rid of
it. Remove the variable since it no longer serves any purpose.

MFC after:	3 days

xen/blkback: do not use x86 CPUID in generic code

2022-06-28T07:51:57+00:00

Move checker for whether Xen creates IOMMU mappings for foreign pages
into a helper that's defined in arch-specific code.

Reported by: Elliott Mitchell 
Fixes: 1d528f95e8ce ('xen/blkback: remove bounce buffering mode')
Sponsored by: Citrix Systems R&D

xen/blkback: remove bounce buffering mode

2022-06-07T10:29:53+00:00

Remove bounce buffering code for blkback and only attach if Xen
creates IOMMU entries for grant mapped pages.

Such bounce buffering consumed a non trivial amount of memory and CPU
resources to do the memory copy, when it's been a long time since Xen
has been creating IOMMU entries for grant maps.

Refuse to attach blkback if Xen doesn't advertise that IOMMU entries
are created for grant maps.

Sponsored by: Citrix Systems R&D

xen/blkback: fix tear-down issues

2022-06-07T10:29:53+00:00

Handle tearing down a blkback that hasn't been fully initialized. This
requires carefully checking that fields are allocated before trying to
access them.  Also communication memory is allocated before setting
XBBF_RING_CONNECTED, so gating it's freeing on XBBF_RING_CONNECTED
being set is wrong and will lead to memory leaks.

Also stop using xbb_disconnect() in error paths. Use xenbus_dev_fatal
and let the normal disconnection procedure take care of the cleanup.

Reported by: Ze Dupsys 
Sponsored by: Citrix Systems R&D

xen: Remove unused devclass arguments to DRIVER_MODULE.

2022-05-06T22:46:58+00:00