History log of /freebsd-current/sys/cam/cam_xpt_sim.h
Revision Date Author Comments
# 95ee2897 16-Aug-2023 Warner Losh <imp@FreeBSD.org>

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

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


# 7af2f2c8 24-Jul-2023 Warner Losh <imp@FreeBSD.org>

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


# 4d846d26 10-May-2023 Warner Losh <imp@FreeBSD.org>

spdx: The BSD-2-Clause-FreeBSD identifier is obsolete, drop -FreeBSD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


# 30f8afd0 28-Jun-2021 Warner Losh <imp@FreeBSD.org>

cam: fix xpt_bus_register and xpt_bus_deregister return errno

xpt_bus_register and xpt_bus_deregister returns a hybrid error that's
neither a cam_status, nor an errno, but a mix of both. Update
xpt_bus_register and xpt_bus_deregister to return an errno. The vast
majority of current users compare against zero, which can also be
spelled CAM_SUCCESS. Nobody uses CAM_FAILURE, so remove that symbol
to prevent comfusion (nothing returns it either).

Where the return value is saved, ensure that the variable 'error' is
used to store an errno and 'status' is used to store a cam_status where
it makes the code clearer (usually just in functions that already mix
and match). Where the return value isn't used at all, avoid storing it
at all.

Reviewed by: scottl@, mav@ (earlier version)
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D30860


# 27dcd3d9 01-Sep-2020 Mateusz Guzik <mjg@FreeBSD.org>

cam: clean up empty lines in .c and .h files


# bec9534d 27-Nov-2017 Pedro F. Giffuni <pfg@FreeBSD.org>

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.


# 227d67aa 20-Oct-2013 Alexander Motin <mav@FreeBSD.org>

Merge CAM locking changes from the projects/camlock branch to radically
reduce lock congestion and improve SMP scalability of the SCSI/ATA stack,
preparing the ground for the coming next GEOM direct dispatch support.

Replace big per-SIM locks with bunch of smaller ones:
- per-LUN locks to protect device and peripheral drivers state;
- per-target locks to protect list of LUNs on target;
- per-bus locks to protect reference counting;
- per-send queue locks to protect queue of CCBs to be sent;
- per-done queue locks to protect queue of completed CCBs;
- remaining per-SIM locks now protect only HBA driver internals.

While holding LUN lock it is allowed (while not recommended for performance
reasons) to take SIM lock. The opposite acquisition order is forbidden.
All the other locks are leaf locks, that can be taken anywhere, but should
not be cascaded. Many functions, such as: xpt_action(), xpt_done(),
xpt_async(), xpt_create_path(), etc. are no longer require (but allow) SIM
lock to be held.

To keep compatibility and solve cases where SIM lock can't be dropped, all
xpt_async() calls in addition to xpt_done() calls are queued to completion
threads for async processing in clean environment without SIM lock held.

Instead of single CAM SWI thread, used for commands completion processing
before, use multiple (depending on number of CPUs) threads. Load balanced
between them using "hash" of the device B:T:L address.

HBA drivers that can drop SIM lock during completion processing and have
sufficient number of completion threads to efficiently scale to multiple
CPUs can use new function xpt_done_direct() to avoid extra context switch.
Make ahci(4) driver to use this mechanism depending on hardware setup.

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


# cccf4220 14-Apr-2013 Alexander Motin <mav@FreeBSD.org>

MFprojects/camlock r248890, r248897, r248898, r248900, r248903, r248905,
r248917, r248918, r248978, r249001, r249014, r249030:

Remove multilevel freezing mechanism, implemented to handle specifics of
the ATA/SATA error recovery, when post-reset recovery commands should be
allocated when queues are already full of payload requests. Instead of
removing frozen CCBs with specified range of priorities from the queue
to provide free openings, use simple hack, allowing explicit CCBs over-
allocation for requests with priority higher (numerically lower) then
CAM_PRIORITY_OOB threshold.

Simplify CCB allocation logic by removing SIM-level allocation queue.
After that SIM-level queue manages only CCBs execution, while allocation
logic is localized within each single device.

Suggested by: gibbs


# 4373522a 04-Apr-2013 Alexander Motin <mav@FreeBSD.org>

Remove xpt_sim_opened(), the only consumer of which was atapicam, which is
now gone.


# 711f6613 12-May-2012 Alexander Motin <mav@FreeBSD.org>

Add two functions xpt_batch_start() and xpt_batch_done() to the CAM SIM KPI
to allow drivers to handle request completion directly without passing
them to the CAM SWI thread removing extra context switch.
Modify all ATA/SATA drivers to use them.

Reviewed by: gibbs, ken
MFC after: 2 weeks


# a7d5f7eb 19-Oct-2010 Jamie Gritton <jamie@FreeBSD.org>

A new jail(8) with a configuration file, to replace the work currently done
by /etc/rc.d/jail.


# 50ae5fde 14-Feb-2010 Alexander Motin <mav@FreeBSD.org>

MFC r203108:
Large set of CAM improvements:
- Unify bus reset/probe sequence. Whenever bus attached at boot or later,
CAM will automatically reset and scan it. It allows to remove duplicate
code from many drivers.
- Any bus, attached before CAM completed it's boot-time initialization,
will equally join to the process, delaying boot if needed.
- New kern.cam.boot_delay loader tunable should help controllers that
are still unable to register their buses in time (such as slow USB/
PCCard/ CardBus devices), by adding one more event to wait on boot.
- To allow synchronization between different CAM levels, concept of
requests priorities was extended. Priorities now split between several
"run levels". Device can be freezed at specified level, allowing higher
priority requests to pass. For example, no payload requests allowed,
until PMP driver enable port. ATA XPT negotiate transfer parameters,
periph driver configure caching and so on.
- Frozen requests are no more counted by request allocation scheduler.
It fixes deadlocks, when frozen low priority payload requests occupying
slots, required by higher levels to manage theit execution.
- Two last changes were holding proper ATA reinitialization and error
recovery implementation. Now it is done: SATA controllers and Port
Multipliers now implement automatic hot-plug and should correctly
recover from timeouts and bus resets.
- Improve SCSI error recovery for devices on buses without automatic sense
reporting, such as ATAPI or USB. For example, it allows CAM to wait, while
CD drive loads disk, instead of immediately return error status.
- Decapitalize diagnostic messages and make them more readable and sensible.
- Teach PMP driver to limit maximum speed on fan-out ports.
- Make boot wait for PMP scan completes, and make rescan more reliable.
- Fix pass driver, to return CCB to user level in case of error.
- Increase number of retries in cd driver, as device may return several UAs.


# 83c5d981 28-Jan-2010 Alexander Motin <mav@FreeBSD.org>

MFp4: Large set of CAM inprovements.

- Unify bus reset/probe sequence. Whenever bus attached at boot or later,
CAM will automatically reset and scan it. It allows to remove duplicate
code from many drivers.
- Any bus, attached before CAM completed it's boot-time initialization,
will equally join to the process, delaying boot if needed.
- New kern.cam.boot_delay loader tunable should help controllers that
are still unable to register their buses in time (such as slow USB/
PCCard/ CardBus devices), by adding one more event to wait on boot.
- To allow synchronization between different CAM levels, concept of
requests priorities was extended. Priorities now split between several
"run levels". Device can be freezed at specified level, allowing higher
priority requests to pass. For example, no payload requests allowed,
until PMP driver enable port. ATA XPT negotiate transfer parameters,
periph driver configure caching and so on.
- Frozen requests are no more counted by request allocation scheduler.
It fixes deadlocks, when frozen low priority payload requests occupying
slots, required by higher levels to manage theit execution.
- Two last changes were holding proper ATA reinitialization and error
recovery implementation. Now it is done: SATA controllers and Port
Multipliers now implement automatic hot-plug and should correctly
recover from timeouts and bus resets.
- Improve SCSI error recovery for devices on buses without automatic sense
reporting, such as ATAPI or USB. For example, it allows CAM to wait, while
CD drive loads disk, instead of immediately return error status.
- Decapitalize diagnostic messages and make them more readable and sensible.
- Teach PMP driver to limit maximum speed on fan-out ports.
- Make boot wait for PMP scan completes, and make rescan more reliable.
- Fix pass driver, to return CCB to user level in case of error.
- Increase number of retries in cd driver, as device may return several UAs.


# 02caf36e 08-Jan-2009 Edward Tomasz Napierala <trasz@FreeBSD.org>

Make "kldunload atapicam" return EBUSY instead of deadlocking when a device
created by atapicam is being kept opened or mounted. This is probably just
a temporary solution until we invent something better.

Reviewed by: scottl
Approved by: rwatson (mentor)
Sponsored by: FreeBSD Foundation
Reported by: Jaakko Heinonen


# d7f03759 19-Oct-2008 Ulf Lilleengen <lulf@FreeBSD.org>

- Import the HEAD csup code which is the basis for the cvsmode work.


# b50569b7 16-Jun-2007 Scott Long <scottl@FreeBSD.org>

Prepare for future integration between CAM and newbus. xpt_bus_register
now takes a device_t to be the parent of the bus that is being created.
Most SIMs have been updated with a reasonable argument, but a few exceptions
just pass NULL for now. This argument isn't used yet and the newbus
integration likely won't be ready until after 7.0-RELEASE.


# 898b0535 05-Jan-2005 Warner Losh <imp@FreeBSD.org>

Start each of the license/copyright comments with /*-


# 434bbf6e 14-Jan-2000 Justin T. Gibbs <gibbs@FreeBSD.org>

Clean up the xpt_sim creation to mirror how HBA drivers perform this task.

Clean up node creation in the EDT so that initialization follows member
declaration.

Sort registered paths by pathid so that we probe busses in order of
ascending pathid. This makes hardwiring of busses without wiring
individual targets do what the user expects. (submitted by tegge@FreeBSD.org)

Fix an EDT node leak. Target nodes would never go away.

Implement xpt_bus_deregister().
(prodded by some patches from T. Ichinoseki, but implemented differently.)


# c4473420 28-Dec-1999 Peter Wemm <peter@FreeBSD.org>

Change #ifdef KERNEL to #ifdef _KERNEL in the public headers. "KERNEL"
is an application space macro and the applications are supposed to be free
to use it as they please (but cannot). This is consistant with the other
BSD's who made this change quite some time ago. More commits to come.


# c3aac50f 27-Aug-1999 Peter Wemm <peter@FreeBSD.org>

$Id$ -> $FreeBSD$


# e5f5a0d8 16-Aug-1999 Justin T. Gibbs <gibbs@FreeBSD.org>

xpt_release_devq now takes a count.


# d1dc9ab1 05-Mar-1999 Justin T. Gibbs <gibbs@FreeBSD.org>

xpt_done has no reason to take a volatile ccb *.


# b4e36adf 27-Jan-1999 Matthew Dillon <dillon@FreeBSD.org>

Fix warnings preparing for -Wall -Wcast-qual

Also disable one usb module in LINT due to fatal compilation errors,
temporary.


# 8b8a9b1d 15-Sep-1998 Justin T. Gibbs <gibbs@FreeBSD.org>

CAM Transport Layer (XPT).

Submitted by: The CAM Team