cam: Let cam_periph_unmapmem() return an error

As of commit b059686a71c8, cam_periph_unmapmem() can legitimately fail
if the copyout() operation fails. However, this failure was never
signaled to u

cam: Let cam_periph_unmapmem() return an error

As of commit b059686a71c8, cam_periph_unmapmem() can legitimately fail
if the copyout() operation fails. However, this failure was never
signaled to upper layers. In practice it is unlikely to occur
since cap_periph_mapmem() would most likely fail in such
circumstances anyway, but an error is nonetheless possible.

However, some code reading revealed a few paths where the return value
of cam_periph_mapmem() is not checked, and this is definitely a bug.
Add error checking there and let cam_periph_unmapmem() return errors
from copyout().

Reviewed by: dab, mav
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D43201

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sys: Remove $FreeBSD$: two-line .h pattern

Remove /^\s*\*\n \*\s+\$FreeBSD\$$\n/

cam: Migrate to modern uintXX_t from u_intXX_t

As per https://lists.freebsd.org/archives/freebsd-scsi/2023-July/000257.html
move to the modern uintXX_t.

MFC After: 3 days
Sponsored by: Netflix

spdx: The BSD-2-Clause-FreeBSD identifier is obsolete, drop -FreeBSD

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

spdx: The BSD-2-Clause-FreeBSD identifier is obsolete, drop -FreeBSD

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

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Delay GEOM disk_create() until CAM periph probe completes.

Before this patch CAM periph drivers called both disk_alloc() and
disk_create() same time on periph creation. But then prevented disks
fro

Delay GEOM disk_create() until CAM periph probe completes.

Before this patch CAM periph drivers called both disk_alloc() and
disk_create() same time on periph creation. But then prevented disks
from opening until the periph probe completion with cam_periph_hold().
As result, especially if disk misbehaves during the probe, GEOM event
thread, triggered to taste the disk, got blocked on open attempt,
potentially for a long time, unable to process other events.

This patch moves disk_create() call from periph creation to the end of
the probe. To allow disk_create() calls from non-sleepable CAM contexts
some of its duties requiring memory allocations are moved either back
to disk_alloc() or forward to g_disk_create(), so now disk_alloc() and
disk_add_alias() are the only disk methods that require sleeping. If
disk fails during the probe disk_create() may just be skipped, going
directly to disk_destroy(). Other method calls during that time are
just ignored. Since GEOM may now see the disks after CAM bus scan is
already completed, introduce per-periph boot hold functions. Enclosure
driver already had such mechanism, so just generalize it.

Reviewed by: imp
MFC after: 1 month
Sponsored by: iXsystems, Inc.
Differential Revision: https://reviews.freebsd.org/D35784

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cam: allocate CCBs from UMA for SCSI and ATA IO

This patch makes it possible for CAM to use small CCBs allocated
from an periph-specific UMA zone instead of the usual, huge ones.
The end result is t

cam: allocate CCBs from UMA for SCSI and ATA IO

This patch makes it possible for CAM to use small CCBs allocated
from an periph-specific UMA zone instead of the usual, huge ones.
The end result is that CCBs issued via da(4) take 544B (size of
ccb_scsiio) instead of the usual 2kB (size of 'union ccb', ~1.5kB,
rounded up by malloc(9)). For ATA it's 272B. We waste less
memory, we avoid zeroing the unused 1kB, and it should be easier
to allocate those CCBs in low memory conditions. It should also
be possible to use uma_zone_reserve(9) to improve behaviour
in low memory conditions even further.

Note that this does not change the size, or the layout, of CCBs
as such. CCBs get allocated in various different ways, in particular
on the stack, and I don't want to redo all that. Instead, this
provides an opt-in mechanism for the periph to declare "my start()
callback is fine with receiving a CCB allocated from this UMA zone".
In other words, most of the code works exactly as it used to; the
change only happens to IOs issued by xpt_run_allockq(), which
is - conveniently - pretty much all that matters for performance.

The reason for doing it this way is that it's pretty small, localized
change, and can be implemented gradually and iteratively: take a
periph, make sure its start() callback only casts the CCBs it takes
to a particular type of CCB, for example ccb_scsiio, and that it only
casts CCBs returned by cam_periph_getccb() to that type, then add UMA
zone for that size, and declare it safe to XPT.

This is disabled by default. Set 'kern.cam.ada.enable_uma_ccbs=1'
and 'kern.cam.da.enable_uma_ccbs=1' tunables to enable it. Testing
is welcome; I will flip the default to enable in two weeks from now.

Reviewed By: imp
Sponsored by: NetApp, Inc.
Sponsored by: Klara, Inc.
Differential Revision: https://reviews.freebsd.org/D28674

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Do not retry long ready waits if previous gave nothing.

I have some disks reporting "Logical unit is in process of becoming ready"
for about half an hour before finally reporting failure. During th

Do not retry long ready waits if previous gave nothing.

I have some disks reporting "Logical unit is in process of becoming ready"
for about half an hour before finally reporting failure. During that time
CAM waits for the readiness during ~2 minutes for each request, that makes
system boot take very long time.

This change reduces wait times for the following requests to ~1 second if
previously long wait for that device has timed out.

MFC after: 2 weeks
Sponsored by: iXsystems, Inc.

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MFHead @348740

Sponsored by: The FreeBSD Foundation

Extract eventfilter declarations to sys/_eventfilter.h

This allows replacing "sys/eventfilter.h" includes with "sys/_eventfilter.h"
in other header files (e.g., sys/{bus,conf,cpu}.h) and reduces hea

Extract eventfilter declarations to sys/_eventfilter.h

This allows replacing "sys/eventfilter.h" includes with "sys/_eventfilter.h"
in other header files (e.g., sys/{bus,conf,cpu}.h) and reduces header
pollution substantially.

EVENTHANDLER_DECLARE and EVENTHANDLER_LIST_DECLAREs were moved out of .c
files into appropriate headers (e.g., sys/proc.h, powernv/opal.h).

As a side effect of reduced header pollution, many .c files and headers no
longer contain needed definitions. The remainder of the patch addresses
adding appropriate includes to fix those files.

LOCK_DEBUG and LOCK_FILE_LINE_ARG are moved to sys/_lock.h, as required by
sys/mutex.h since r326106 (but silently protected by header pollution prior
to this change).

No functional change (intended). Of course, any out of tree modules that
relied on header pollution for sys/eventhandler.h, sys/lock.h, or
sys/mutex.h inclusion need to be fixed. __FreeBSD_version has been bumped.

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MFHead@r345677

Do not map small IOCTL buffers to KVA, but copy.

CAM IOCTL interfaces traditionally mapped user-space data buffers to KVA.
It was nice originally, but now it takes too much to handle respective
TLB

Do not map small IOCTL buffers to KVA, but copy.

CAM IOCTL interfaces traditionally mapped user-space data buffers to KVA.
It was nice originally, but now it takes too much to handle respective
TLB shootdowns, while small kernel memory allocations up to 64KB backed
by UMA and accompanied by copyin()/copyout() can be much cheaper.

For large buffers mapping still may have sense, and unmapped I/O would
be even better, but the last unfortunately is more tricky, since unmapped
I/O API is too specific to struct bio now.

MFC after: 2 weeks
Sponsored by: iXsystems, Inc.

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Create a sysctl kern.cam.{,a,n}da.X.invalidate

kern.cam.{,a,n}da.X.invalidate=1 forces *daX to detach by calling
cam_periph_invalidate on the underlying periph. This is for testing
purposes only. In

Create a sysctl kern.cam.{,a,n}da.X.invalidate

kern.cam.{,a,n}da.X.invalidate=1 forces *daX to detach by calling
cam_periph_invalidate on the underlying periph. This is for testing
purposes only. Include only with options CAM_TEST_FAILURE and rename
the former [AN]DA_TEST_FAILURE, and fix nda to compile with it set.
We're using it at work to harden geom and the buffer cache to be
resilient in the face of drive failure. Today, it far too often
results in a panic. While much work was done on SIM initiated removal
for the USB thumnb drive removal work, little has been done for periph
initiated removal. This simulates what *daerror() does for some errors
nicely: we get the same panics with it that we do with failing drives.

Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D14581

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Return a C errno for cam_periph_acquire().

There's no compelling reason to return a cam_status type for this
function and doing so only creates confusion with normal C
coding practices. It's technic

Return a C errno for cam_periph_acquire().

There's no compelling reason to return a cam_status type for this
function and doing so only creates confusion with normal C
coding practices. It's technically an API change, but the periph API
isn't widely used. No efffective change to operation.

Reviewed by: imp, mav, ken
Sponsored by: Netflix
Differential Revision: D14063

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Move CAM_PERIPH_PRINT() to cam_periph.h

Merge ^/head r327624 through r327885.

Protect against a possible NULL deference from an accessor
function.

Obtained from: Netflix

Remove unused 4th argument to match the standard error routines.

Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D13386

sys/cam: further adoption of SPDX licensing ID tags.

Mainly focus on files that use BSD 2-Clause license, however the tool I
was using misidentified many licenses so this was mostly a manual - error

sys/cam: further adoption of SPDX licensing ID tags.

Mainly focus on files that use BSD 2-Clause license, however the tool I
was using misidentified many licenses so this was mostly a manual - error
prone - task.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.

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Add mechanism to unload CAM periph drivers.

For now it allows to unload CTL kernel module if there are no target-capable
SIMs in CAM. As next step full teardown of CAM targets can be implemented.

Merge ^/head r306412 through r306905.

cam_periph_ccbwait could return while ccb in progress

In cam_periph_runccb, cam_periph_ccbwait was using the value of the ccb
pinfo.index and status fields to determine whether the ccb was done,
but

cam_periph_ccbwait could return while ccb in progress

In cam_periph_runccb, cam_periph_ccbwait was using the value of the ccb
pinfo.index and status fields to determine whether the ccb was done,
but these fields are updated without a contending lock and could glitch
into states that would be erroneously interpreted as done. Instead,
have cam_periph_ccbwait look for the explicit result of the function
cam_periph_done.

Submitted by: Ryan Libby <rlibby@gmail.com>
Reviewed by: mav
MFC after: 3 weeks
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D8020

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Merge from head

Sponsored by: Gandi.net

Merge from head

Sync up with head up to r289211.

Merge ^/head r288197 through r288456.