Commit Graph

103 Commits

Author SHA1 Message Date
mav
c8679b8bb2 Drop periph lock around cam_periph_unmapmem().
Since r345656 it may call copyout(), that may sleep.

MFC after:	3 days
Sponsored by:	iXsystems, Inc.
2019-05-06 19:08:03 +00:00
scottl
2452912a61 cam_periph_runccb() changed several years ago to overwrite the ccb callback
pointer.  It's now unhelpful and misleading for callers to continue to set
it, so bring all callers into conformance.  There's no real functional change,
but it makes reading the code a lot less confusing.

Sponsored by:	Netflix
2018-05-01 20:09:29 +00:00
brooks
9d79658aab Move most of the contents of opt_compat.h to opt_global.h.
opt_compat.h is mentioned in nearly 180 files. In-progress network
driver compabibility improvements may add over 100 more so this is
closer to "just about everywhere" than "only some files" per the
guidance in sys/conf/options.

Keep COMPAT_LINUX32 in opt_compat.h as it is confined to a subset of
sys/compat/linux/*.c.  A fake _COMPAT_LINUX option ensure opt_compat.h
is created on all architectures.

Move COMPAT_LINUXKPI to opt_dontuse.h as it is only used to control the
set of compiled files.

Reviewed by:	kib, cem, jhb, jtl
Sponsored by:	DARPA, AFRL
Differential Revision:	https://reviews.freebsd.org/D14941
2018-04-06 17:35:35 +00:00
brooks
8e8de6204b Reject CAMIOGET and CAMIOQUEUE ioctl's on pass(4) in 32-bit compat mode.
These take a union ccb argument which is full of kernel pointers.
Substantial translation efforts would be required to make this work.
By rejecting the request we avoid processing or returning entierly
wrong data.

Reviewed by:	imp, ken, markj, cem
Obtained from:	CheriBSD
MFC after:	1 week
Sponsored by:	DARPA, AFRL
Differential Revision:	https://reviews.freebsd.org/D14654
2018-03-12 22:58:07 +00:00
scottl
e437fbd6d8 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
2018-02-06 06:42:25 +00:00
kan
c8da6fae2c Do pass removing some write-only variables from the kernel.
This reduces noise when kernel is compiled by newer GCC versions,
such as one used by external toolchain ports.

Reviewed by: kib, andrew(sys/arm and sys/arm64), emaste(partial), erj(partial)
Reviewed by: jhb (sys/dev/pci/* sys/kern/vfs_aio.c and sys/kern/kern_synch.c)
Differential Revision: https://reviews.freebsd.org/D10385
2017-12-25 04:48:39 +00:00
imp
e3a601760b Define xpt_path_inq.
This provides a nice wrarpper around the XPT_PATH_INQ ccb creation and
calling.

Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D13387
2017-12-06 23:05:22 +00:00
imp
e461367ac8 Remove unused 4th argument to match the standard error routines.
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D13386
2017-12-06 00:29:50 +00:00
pfg
39ac7c1b27 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.
2017-11-27 15:12:43 +00:00
imp
49559f2464 Add missing test for NVME CCBs for nvme passthru support.
Submitted by: Chuck Tuffli
2017-08-29 21:04:29 +00:00
imp
6267655c2e Add CAM/NVMe support for CAM_DATA_SG
This adds support in pass(4) for data to be described with a
scatter-gather list (sglist) to augment the existing (single) virtual
address.

Differential Revision: https://reviews.freebsd.org/D11361
Submitted by: Chuck Tuffli
Reviewed by: imp@, scottl@, kenm@
2017-08-29 15:29:57 +00:00
imp
4859d0d3e7 This adds CAM pass(4) support for NVMe IO's. Applications indicate
the IO type (Admin or NVM) using XPT op-codes XPT_NVME_ADMIN or
XPT_NVME_IO.

Submitted by:   Chuck Tuffli <chuck@tuffli.net>
Differential Revision:  https://reviews.freebsd.org/D10247
2017-07-14 14:52:20 +00:00
imp
a87c7a85be An MMC/SD/SDIO stack using CAM
Implement the MMC/SD/SDIO protocol within a CAM framework. CAM's
flexible queueing will make it easier to write non-storage drivers
than the legacy stack. SDIO drivers from both the kernel and as
userland daemons are possible, though much of that functionality will
come later.

Some of the CAM integration isn't complete (there are sleeps in the
device probe state machine, for example), but those minor issues can
be improved in-tree more easily than out of tree and shouldn't gate
progress on other fronts. Appologies to reviews if specific items
have been overlooked.

Submitted by: Ilya Bakulin
Reviewed by: emaste, imp, mav, adrian, ian
Differential Review: https://reviews.freebsd.org/D4761

merge with first commit, various compile hacks.
2017-07-09 16:57:24 +00:00
ken
477d3db78f Fix error recovery behavior in the pass(4) driver.
After FreeBSD SVN revision 236814, the pass(4) driver changed from
only doing error recovery when the CAM_PASS_ERR_RECOVER flag was
set on a CCB to sometimes doing error recovery if the passed in
retry count was non-zero.

Error recovery would happen if two conditions were met:

1.  The error recovery action was simply a retry.  (Which is most
    cases.)
2.  The retry_count is non-zero. (Which happened a lot because of
    cut-and-pasted code.)

This explains a bug I noticed in with camcontrol:

# camcontrol tur da34 -v
Unit is ready
# camcontrol reset da34
Reset of 1:172:0 was successful

At this point, there should be a Unit Attention:

# camcontrol tur da34 -v
Unit is ready

No Unit Attention.

Try it again:

# camcontrol reset da34
Reset of 1:172:0 was successful

Now set the retry_count to 0 for the TUR:

# camcontrol tur da34 -v -C 0
Unit is not ready
(pass42:mps1:0:172:0): TEST UNIT READY. CDB: 00 00 00 00 00 00
(pass42:mps1:0:172:0): CAM status: SCSI Status Error
(pass42:mps1:0:172:0): SCSI status: Check Condition
(pass42:mps1:0:172:0): SCSI sense: UNIT ATTENTION asc:29,2 (SCSI bus reset occurred)
(pass42:mps1:0:172:0): Field Replaceable Unit: 2

There is the unit attention. camcontrol(8) has a default
retry_count of 1, in case someone sets the -E flag without
setting -C.

The CAM_PASS_ERR_RECOVER behavior was only broken with the
CAMIOCOMMAND ioctl, which is the synchronous pass(4) API.  It has
worked as intended (error recovery is only done when the flag
is set) in the asynchronous API (CAMIOQUEUE ioctl).

sys/cam/scsi/scsi_pass.c:
	In passsendccb(), when calling cam_periph_runccb(), only
	specify the error routine when CAM_PASS_ERR_RECOVER is set.

share/man/man4/pass.4:
	Document that CAM_PASS_ERR_RECOVER is needed to enable
	error recovery.

Reported by:	Terry Kennedy <TERRY@glaver.org>
PR:		kern/218572
MFC after:	1 week
Sponsored by:	Spectra Logic
2017-05-03 20:59:47 +00:00
markj
aee44fc238 Reject userland CCBs that have CAM_UNLOCKED set.
CAM_UNLOCKED is internal flag and cannot correctly be set by userland.
Return EINVAL from CAMIOCOMMAND and CAMIOQUEUE if it is set.

Also fix leaks in some of the error paths for CAMIOQUEUE.

PR:		215356
Reviewed by:	ken, mav
MFC after:	1 week
Differential Revision:	https://reviews.freebsd.org/D9869
2017-03-03 20:51:57 +00:00
cem
3b49140b27 cam: Zero bio pointer in user-supplied SCSI CCBs
The BUF_TRACKING bio pointer only makes sense for kernel consumers of
CCBs.

PR:		214250
Reported by:	trasz@
Reviewed by:	imp@, markj@
Sponsored by:	Dell EMC Isilon
Differential Revision:	https://reviews.freebsd.org/D8477
2016-11-08 21:17:24 +00:00
mav
7945b79f20 Make pass driver better support CAM_CDB_POINTER flag.
Previously pass driver just ignored the flag, making random kernel code
access user-space pointer, sometime causing crashes even for correctly
written applications if user-level context was switched or swapped out.
This patch tries to copyin the CDB into kernel space to avoid it.

MFC after:	2 weeks
2016-10-17 15:02:17 +00:00
markj
fc8a4ae06d opt_kdtrace.h is not needed for SDT probes as of r258541. 2016-05-15 20:04:43 +00:00
imp
1821739d94 tag_action is not used at all in ata. It's set to 1 for ordered
transactions, but that value isn't used. It's bogusly used to report
in devstat, due to a cut and paste error from SCSI. Mark it as unused
in cam_fill_ataio. Reclaim the memory as a new ata_flags. In addition,
tag_id and init_id are completely unused, so reclaim those as 'unused'
now too. These were needlessly copied when ata was split from scsi.

This allows us, in the future, to create structures that can
communicate AUXILIARY regsiter to the SIMs, which cannot be done now.

Differential Revision: https://reviews.freebsd.org/D5598
2016-04-17 05:24:28 +00:00
araujo
bf546063c0 Clean up unused-but-set-variable spotted by gcc-4.9.
Reviewed by:	mav
Approved by:	rodrigc (mentor)
MFC after:	2 weeks
Sponsored by:	gandi.net
Differential Revision:	https://reviews.freebsd.org/D5109
2016-02-01 02:33:58 +00:00
kib
b96b9a6148 Convert sys/cam to use make_dev_s().
Reviewed by:	hps, jhb
Sponsored by:	The FreeBSD Foundation
MFC after:	3 weeks
Differential revision:	https://reviews.freebsd.org/D4746
2016-01-07 20:22:55 +00:00
ken
d0f081c521 Add asynchronous command support to the pass(4) driver, and the new
camdd(8) utility.

CCBs may be queued to the driver via the new CAMIOQUEUE ioctl, and
completed CCBs may be retrieved via the CAMIOGET ioctl.  User
processes can use poll(2) or kevent(2) to get notification when
I/O has completed.

While the existing CAMIOCOMMAND blocking ioctl interface only
supports user virtual data pointers in a CCB (generally only
one per CCB), the new CAMIOQUEUE ioctl supports user virtual and
physical address pointers, as well as user virtual and physical
scatter/gather lists.  This allows user applications to have more
flexibility in their data handling operations.

Kernel memory for data transferred via the queued interface is
allocated from the zone allocator in MAXPHYS sized chunks, and user
data is copied in and out.  This is likely faster than the
vmapbuf()/vunmapbuf() method used by the CAMIOCOMMAND ioctl in
configurations with many processors (there are more TLB shootdowns
caused by the mapping/unmapping operation) but may not be as fast
as running with unmapped I/O.

The new memory handling model for user requests also allows
applications to send CCBs with request sizes that are larger than
MAXPHYS.  The pass(4) driver now limits queued requests to the I/O
size listed by the SIM driver in the maxio field in the Path
Inquiry (XPT_PATH_INQ) CCB.

There are some things things would be good to add:

1. Come up with a way to do unmapped I/O on multiple buffers.
   Currently the unmapped I/O interface operates on a struct bio,
   which includes only one address and length.  It would be nice
   to be able to send an unmapped scatter/gather list down to
   busdma.  This would allow eliminating the copy we currently do
   for data.

2. Add an ioctl to list currently outstanding CCBs in the various
   queues.

3. Add an ioctl to cancel a request, or use the XPT_ABORT CCB to do
   that.

4. Test physical address support.  Virtual pointers and scatter
   gather lists have been tested, but I have not yet tested
   physical addresses or scatter/gather lists.

5. Investigate multiple queue support.  At the moment there is one
   queue of commands per pass(4) device.  If multiple processes
   open the device, they will submit I/O into the same queue and
   get events for the same completions.  This is probably the right
   model for most applications, but it is something that could be
   changed later on.

Also, add a new utility, camdd(8) that uses the asynchronous pass(4)
driver interface.

This utility is intended to be a basic data transfer/copy utility,
a simple benchmark utility, and an example of how to use the
asynchronous pass(4) interface.

It can copy data to and from pass(4) devices using any target queue
depth, starting offset and blocksize for the input and ouptut devices.
It currently only supports SCSI devices, but could be easily extended
to support ATA devices.

It can also copy data to and from regular files, block devices, tape
devices, pipes, stdin, and stdout.  It does not support queueing
multiple commands to any of those targets, since it uses the standard
read(2)/write(2)/writev(2)/readv(2) system calls.

The I/O is done by two threads, one for the reader and one for the
writer.  The reader thread sends completed read requests to the
writer thread in strictly sequential order, even if they complete
out of order.  That could be modified later on for random I/O patterns
or slightly out of order I/O.

camdd(8) uses kqueue(2)/kevent(2) to get I/O completion events from
the pass(4) driver and also to send request notifications internally.

For pass(4) devcies, camdd(8) uses a single buffer (CAM_DATA_VADDR)
per CAM CCB on the reading side, and a scatter/gather list
(CAM_DATA_SG) on the writing side.  In addition to testing both
interfaces, this makes any potential reblocking of I/O easier.  No
data is copied between the reader and the writer, but rather the
reader's buffers are split into multiple I/O requests or combined
into a single I/O request depending on the input and output blocksize.

For the file I/O path, camdd(8) also uses a single buffer (read(2),
write(2), pread(2) or pwrite(2)) on reads, and a scatter/gather list
(readv(2), writev(2), preadv(2), pwritev(2)) on writes.

Things that would be nice to do for camdd(8) eventually:

1.  Add support for I/O pattern generation.  Patterns like all
    zeros, all ones, LBA-based patterns, random patterns, etc. Right
    Now you can always use /dev/zero, /dev/random, etc.

2.  Add support for a "sink" mode, so we do only reads with no
    writes.  Right now, you can use /dev/null.

3.  Add support for automatic queue depth probing, so that we can
    figure out the right queue depth on the input and output side
    for maximum throughput.  At the moment it defaults to 6.

4.  Add support for SATA device passthrough I/O.

5.  Add support for random LBAs and/or lengths on the input and
    output sides.

6.  Track average per-I/O latency and busy time.  The busy time
    and latency could also feed in to the automatic queue depth
    determination.

sys/cam/scsi/scsi_pass.h:
	Define two new ioctls, CAMIOQUEUE and CAMIOGET, that queue
	and fetch asynchronous CAM CCBs respectively.

	Although these ioctls do not have a declared argument, they
	both take a union ccb pointer.  If we declare a size here,
	the ioctl code in sys/kern/sys_generic.c will malloc and free
	a buffer for either the CCB or the CCB pointer (depending on
	how it is declared).  Since we have to keep a copy of the
	CCB (which is fairly large) anyway, having the ioctl malloc
	and free a CCB for each call is wasteful.

sys/cam/scsi/scsi_pass.c:
	Add asynchronous CCB support.

	Add two new ioctls, CAMIOQUEUE and CAMIOGET.

	CAMIOQUEUE adds a CCB to the incoming queue.  The CCB is
	executed immediately (and moved to the active queue) if it
	is an immediate CCB, but otherwise it will be executed
	in passstart() when a CCB is available from the transport layer.

	When CCBs are completed (because they are immediate or
	passdone() if they are queued), they are put on the done
	queue.

	If we get the final close on the device before all pending
	I/O is complete, all active I/O is moved to the abandoned
	queue and we increment the peripheral reference count so
	that the peripheral driver instance doesn't go away before
	all pending I/O is done.

	The new passcreatezone() function is called on the first
	call to the CAMIOQUEUE ioctl on a given device to allocate
	the UMA zones for I/O requests and S/G list buffers.  This
	may be good to move off to a taskqueue at some point.
	The new passmemsetup() function allocates memory and
	scatter/gather lists to hold the user's data, and copies
	in any data that needs to be written.  For virtual pointers
	(CAM_DATA_VADDR), the kernel buffer is malloced from the
	new pass(4) driver malloc bucket.  For virtual
	scatter/gather lists (CAM_DATA_SG), buffers are allocated
	from a new per-pass(9) UMA zone in MAXPHYS-sized chunks.
	Physical pointers are passed in unchanged.  We have support
	for up to 16 scatter/gather segments (for the user and
	kernel S/G lists) in the default struct pass_io_req, so
	requests with longer S/G lists require an extra kernel malloc.

	The new passcopysglist() function copies a user scatter/gather
	list to a kernel scatter/gather list.  The number of elements
	in each list may be different, but (obviously) the amount of data
	stored has to be identical.

	The new passmemdone() function copies data out for the
	CAM_DATA_VADDR and CAM_DATA_SG cases.

	The new passiocleanup() function restores data pointers in
	user CCBs and frees memory.

	Add new functions to support kqueue(2)/kevent(2):

	passreadfilt() tells kevent whether or not the done
	queue is empty.

	passkqfilter() adds a knote to our list.

	passreadfiltdetach() removes a knote from our list.

	Add a new function, passpoll(), for poll(2)/select(2)
	to use.

	Add devstat(9) support for the queued CCB path.

sys/cam/ata/ata_da.c:
	Add support for the BIO_VLIST bio type.

sys/cam/cam_ccb.h:
	Add a new enumeration for the xflags field in the CCB header.
	(This doesn't change the CCB header, just adds an enumeration to
	use.)

sys/cam/cam_xpt.c:
	Add a new function, xpt_setup_ccb_flags(), that allows specifying
	CCB flags.

sys/cam/cam_xpt.h:
	Add a prototype for xpt_setup_ccb_flags().

sys/cam/scsi/scsi_da.c:
	Add support for BIO_VLIST.

sys/dev/md/md.c:
	Add BIO_VLIST support to md(4).

sys/geom/geom_disk.c:
	Add BIO_VLIST support to the GEOM disk class.  Re-factor the I/O size
	limiting code in g_disk_start() a bit.

sys/kern/subr_bus_dma.c:
	Change _bus_dmamap_load_vlist() to take a starting offset and
	length.

	Add a new function, _bus_dmamap_load_pages(), that will load a list
	of physical pages starting at an offset.

	Update _bus_dmamap_load_bio() to allow loading BIO_VLIST bios.
	Allow unmapped I/O to start at an offset.

sys/kern/subr_uio.c:
	Add two new functions, physcopyin_vlist() and physcopyout_vlist().

sys/pc98/include/bus.h:
	Guard kernel-only parts of the pc98 machine/bus.h header with
	#ifdef _KERNEL.

	This allows userland programs to include <machine/bus.h> to get the
	definition of bus_addr_t and bus_size_t.

sys/sys/bio.h:
	Add a new bio flag, BIO_VLIST.

sys/sys/uio.h:
	Add prototypes for physcopyin_vlist() and physcopyout_vlist().

share/man/man4/pass.4:
	Document the CAMIOQUEUE and CAMIOGET ioctls.

usr.sbin/Makefile:
	Add camdd.

usr.sbin/camdd/Makefile:
	Add a makefile for camdd(8).

usr.sbin/camdd/camdd.8:
	Man page for camdd(8).

usr.sbin/camdd/camdd.c:
	The new camdd(8) utility.

Sponsored by:	Spectra Logic
MFC after:	1 week
2015-12-03 20:54:55 +00:00
mav
efed61f85c Make pass, sg and targ drivers respect HBA's maxio.
Previous limitation of 64K (DFLTPHYS) is quite annoying.
2015-09-30 13:31:37 +00:00
imp
eebc91c3f0 Remove instances of variables that were set, but never used. gcc 4.9
warns about these by default.
2014-03-30 23:43:36 +00:00
mav
99ff385fd0 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
2013-10-21 12:00:26 +00:00
mav
75519cc725 Unify periph invalidation and destruction reporting.
Print message containing device model and serial number on invalidation.

Requested by:   glebius
MFC after:	1 week
2013-10-15 17:59:41 +00:00
scottl
e2e8dc4dbb Re-do r255853. Along with adding back the API/ABI changes from the
original, this hides the contents of cam_compat.h from ktrace/kdump/truss,
avoiding problems there.  There are no user-servicable parts in there, so
no need for those tools to be groping around in there.

Approved by:	re
2013-09-25 15:55:56 +00:00
gjb
d965f28ba1 Revert r255853 pending fixes to build errors in usr.bin/kdump
Approved by:	re (implicit)
2013-09-25 01:48:45 +00:00
scottl
108b7070e7 Update the CAM API for FreeBSD 10:
- Remove the timeout_ch field.  It's been deprecated since FreeBSD 7.0;
  MPSAFE drivers should be managing their own timeout storage.  The
  remaining non-MPSAFE drivers have been modified to also manage their own
  storage, and should be considered for updating to MPSAFE (or removal)
  during the FreeBSD 10.x lifecycle.

- Add fields related to soft timeouts and quality of service, to be used
  in upcoming work.

- Add room for more flags in the CCB header and path_inq structures.

- Begin support for extended 64-bit LUNs.

- Bump the CAM version number to 0x18, but add compat shims.  Tested with
  camcontrol and smartctl.

Reviewed by:    nathanw, ken, kib
Approved by:    re
Obtained from:  Netflix
2013-09-24 16:50:53 +00:00
scottl
95ba85598a Add infrastructure for doing compatibility shims, as has been sorely
needed for the last 10 years.  Far too much of the internal API is
exposed, and every small adjustment causes applications to stop working.
To kick this off, bump the API version to 0x17 as should have been done
with r246713, but add shims to compensate.  Thanks to the shims, there
should be no visible change in application behavior.

I have plans to do a significant overhaul of the API to harnen it for
the future, but until then, I welcome others to add shims for older
versions of the API.

Obtained from:	Netflix
2013-06-17 08:57:09 +00:00
scottl
3300ef5cf8 Simplify the checking of flags for cam_periph_mapmem(). This gets rid of
a lot of code redundancy and grossness at very minor expense.

Reviewed by:	smh
Obtained from:	Netflix
MFC after:	3 days
2013-06-07 00:22:38 +00:00
gabor
d3ee8e3ff6 - Correct mispellings of the word occurrence
Submitted by:	Christoph Mallon <christoph.mallon@gmx.de> (via private mail)
2013-04-17 11:40:10 +00:00
mav
f73c311ca3 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
2013-04-14 09:28:14 +00:00
mav
a67b1a1c2d MFprojects/camlock r248931:
Replace some direct mutex operations with wrappers.

MFC after:	2 weeks
2013-04-04 19:07:37 +00:00
kib
bd7f0fa0bb Reform the busdma API so that new types may be added without modifying
every architecture's busdma_machdep.c.  It is done by unifying the
bus_dmamap_load_buffer() routines so that they may be called from MI
code.  The MD busdma is then given a chance to do any final processing
in the complete() callback.

The cam changes unify the bus_dmamap_load* handling in cam drivers.

The arm and mips implementations are updated to track virtual
addresses for sync().  Previously this was done in a type specific
way.  Now it is done in a generic way by recording the list of
virtuals in the map.

Submitted by:	jeff (sponsored by EMC/Isilon)
Reviewed by:	kan (previous version), scottl,
	mjacob (isp(4), no objections for target mode changes)
Discussed with:	     ian (arm changes)
Tested by:	marius (sparc64), mips (jmallet), isci(4) on x86 (jharris),
	amd64 (Fabian Keil <freebsd-listen@fabiankeil.de>)
2013-02-12 16:57:20 +00:00
ken
ff1edb089b Fix a device departure bug for the the pass(4), enc(4), sg(4) and ch(4)
drivers.

The bug occurrs when a userland process has the driver instance
open and the underlying device goes away.  We get the devfs
callback that the device node has been destroyed, but not all of
the closes necessary to fully decrement the reference count on the
CAM peripheral.

The reason is that once devfs calls back and says the device has
been destroyed, it is moved off to deadfs, and devfs guarantees
that there will be no more open or close calls.  So the solution
is to keep track of how many outstanding open calls there are on
the device, and just release that many references when we get the
callback from devfs.

scsi_pass.c,
scsi_enc.c,
scsi_enc_internal.h:	Add an open count to the softc in these
			drivers.  Increment it on open and
			decrement it on close.

			When we get a devfs callback to say that
			the device node has gone away, decrement
			the peripheral reference count by the
			number of still outstanding opens.

			Make sure we don't access the peripheral
			with cam_periph_unlock() after what might
			be the final call to
			cam_periph_release_locked().  The
			peripheral might have been freed, and we
			will be dereferencing freed memory.

scsi_ch.c,
scsi_sg.c:		For the ch(4) and sg(4) drivers, add the
			same changes described above, and in
			addition, fix another bug that was
			previously fixed in the pass(4) and enc(4)
			drivers.

			These drivers were calling destroy_dev()
			from their cleanup routine, but that could
			cause a deadlock because the cleanup
			routine could be indirectly called from
			the driver's close routine.  This would
			cause a deadlock, because the device node
			is being held open by the active close
			call, and can't be destroyed.

Sponsored by:	Spectra Logic Corporation
MFC after:	1 week
2012-12-08 04:03:04 +00:00
mav
dd686c1964 Remove priority enforcement from xpt_ation(). It is not good and even not
safe in some cases to reduce CCB priority after it was scheduled with high
priority.  This fixes reproducible deadlock when command sent through the
pass interface while ATA XPT recovers from command timeout.

Instead of that enforce priority at passioctl().  libcam provides no obvious
interface to specify CCB priority and so much (all?) code specifies zero
(highest) priority.  This change limits pass CCBs priority to NORMAL run
level, allowing XPT to complete bus and device recovery after reset before
running any payload.
2012-10-27 10:14:12 +00:00
mav
c5f476d2d7 Protect xpt_getattr() calls with the SIM lock and assert that.
Submitted by:	ken@ (earlier version)
2012-10-12 17:18:24 +00:00
mav
35f2c3dc00 Remove 'periph == NULL' check from bunch of periph drivers.
This condition can never be true as functions are called from single place
and the checks just pollute the code and confuse Clang Static Analyzer.
2012-10-10 18:10:11 +00:00
ken
188f5a2133 Fix several reference counting and object lifetime issues between
the pass(4) and enc(4) drivers and devfs.

The pass(4) driver uses the destroy_dev_sched() routine to
schedule its device node for destruction in a separate thread
context.  It does this because the passcleanup() routine can get
called indirectly from the passclose() routine, and that would
cause a deadlock if the close routine tried to destroy its own
device node.

In any case, once a particular passthrough driver number, e.g.
pass3, is destroyed, CAM considers that unit number (3 in this
case) available for reuse.

The problem is that devfs may not be done cleaning up the previous
instance of pass3, and will panic if isn't done cleaning up the
previous instance.

The solution is to get a callback from devfs when the device node
is removed, and make sure we hold a reference to the peripheral
until that happens.

Testing exposed some other cases where we have reference counting
issues, and those were also fixed in the pass(4) driver.

cam_periph.c:	In camperiphfree(), reorder some of the operations.

		The peripheral destructor needs to be called before
		the peripheral is removed from the peripheral is
		removed from the list.  This is because once we
		remove the peripheral from the list, and drop the
		topology lock, the peripheral number may be reused.
		But if the destructor hasn't been called yet, there
		may still be resources hanging around (like devfs
		nodes) that haven't been fully cleaned up.

cam_xpt.c:	Add an argument to xpt_remove_periph() to indicate
		whether the topology lock is already held.

scsi_enc.c:	Acquire an extra reference to the peripheral during
		registration, and release it once we get a callback
		from devfs indicating that the device node is gone.

		Call destroy_dev_sched_cb() in enc_oninvalidate()
		instead of calling destroy_dev() in the cleanup
		routine.

scsi_pass.c:	Add reference counting to handle peripheral and
		devfs object lifetime issues.

		Add a reference to the peripheral and the devfs
		node in the peripheral registration.

		Don't attempt to add a physical path alias if the
		peripheral has been marked invalid.

		Release the devfs reference once the initial
		physical path alias taskqueue run has completed.

		Schedule devfs node destruction in the
		passoninvalidate(), and release our peripheral
		reference in a new routine, passdevgonecb() once
		the devfs node is gone.  This allows the peripheral
		to fully go away, and the peripheral destructor,
		passcleanup(), will get called.

MFC after:	3 days
Sponsored by:	Spectra Logic
2012-06-20 17:08:00 +00:00
mav
478d881b57 One more major cam_periph_error() rewrite to improve error handling and
reporting. It includes:
 - removing of error messages controlled by bootverbose, replacing them
with more universal and informative debugging on CAM_DEBUG_INFO level,
that is now built into the kernel by default;
 - more close following to the arguments submitted by caller, such as
SF_PRINT_ALWAYS, SF_QUIET_IR and SF_NO_PRINT; consumer knows better which
errors are usual/expected at this point and which are really informative;
 - adding two new flags SF_NO_RECOVERY and SF_NO_RETRY to allow caller
specify how much assistance it needs at this point; previously consumers
controlled that by not calling cam_periph_error() at all, but that made
behavior inconsistent and debugging complicated;
 - tuning debug messages and taken actions order to make debugging output
more readable and cause-effect relationships visible;
 - making camperiphdone() (common device recovery completion handler) to
also use cam_periph_error() in most cases, instead of own dumb code;
 - removing manual sense fetching code from cam_periph_error(); I was told
by number of people that it is SIM obligation to fetch sense data, so this
code is useless and only significantly complicates recovery logic;
 - making ada, da and pass driver to use cam_periph_error() with new limited
recovery options to handle error recovery and debugging in common way;
as one of results, CAM_REQUEUE_REQ and other retrying statuses are now
working fine with pass driver, that caused many problems before.
 - reverting r186891 by raj@ to avoid burning few seconds in tight DELAY()
loops on device probe, while device simply loads media; I think that problem
may already be fixed in other way, and even if it is not, solution must be
different.

Sponsored by:	iXsystems, Inc.
MFC after:	2 weeks
2012-06-09 13:07:44 +00:00
ken
498f14d067 Work around a race condition in devfs by changing the way closes
are handled in most CAM peripheral drivers that are not handled by
GEOM's disk class.

The usual character driver open and close semantics are that the
driver gets N open calls, but only one close, when the last caller
closes the device.

CAM peripheral drivers expect that behavior to be honored to the
letter, and the CAM peripheral driver code (specifically
cam_periph_release_locked_busses()) panics if it is done incorrectly.

Since devfs has to drop its locks while it calls a driver's close
routine, and it does not have a way to delay or prevent open calls
while it is calling the close routine, there is a race.

The sequence of events, simplified a bit, is:

- devfs acquires a lock
- devfs checks the reference count, and if it is 1, continues to close.
- devfs releases the lock

- 2nd process open call on the device happens here

- devfs calls the driver's close routine

- devfs acquires a lock
- devfs decrements the reference count
- devfs releases the lock

- 2nd process close call on the device happens here

At the second close, we get a panic in
cam_periph_release_locked_busses(), complaining that peripheral
has been released when the reference count is already 0.  This is
because we have gotten two closes in a row, which should not
happen.

The fix is to add the D_TRACKCLOSE flag to the driver's cdevsw, so
that we get a close() call for each open().  That does happen
reliably, so we can make sure that our reference counts are
correct.

Note that the sa(4) and pt(4) drivers only allow one context
through the open routine.  So these drivers aren't exposed to the
same race condition.

scsi_ch.c,
scsi_enc.c,
scsi_enc_internal.h,
scsi_pass.c,
scsi_sg.c:
		For these drivers, change the open() routine to
		increment the reference count for every open, and
		just decrement the reference count in the close.

		Call cam_periph_release_locked() in some scenarios
		to avoid additional lock and unlock calls.

scsi_pt.c:	Call cam_periph_release_locked() in some scenarios
		to avoid additional lock and unlock calls.

MFC after:	3 days
2012-05-27 06:11:09 +00:00
gibbs
094b6aca1d Plumb device physical path reporting from CAM devices, through GEOM and
DEVFS, and make it accessible via the diskinfo utility.

Extend GEOM's generic attribute query mechanism into generic disk consumers.
sys/geom/geom_disk.c:
sys/geom/geom_disk.h:
sys/cam/scsi/scsi_da.c:
sys/cam/ata/ata_da.c:
	- Allow disk providers to implement a new method which can override
	  the default BIO_GETATTR response, d_getattr(struct bio *).  This
	  function returns -1 if not handled, otherwise it returns 0 or an
	  errno to be passed to g_io_deliver().

sys/cam/scsi/scsi_da.c:
sys/cam/ata/ata_da.c:
	- Don't copy the serial number to dp->d_ident anymore, as the CAM XPT
	  is now responsible for returning this information via
	  d_getattr()->(a)dagetattr()->xpt_getatr().

sys/geom/geom_dev.c:
	- Implement a new ioctl, DIOCGPHYSPATH, which returns the GEOM
	  attribute "GEOM::physpath", if possible.  If the attribute request
	  returns a zero-length string, ENOENT is returned.

usr.sbin/diskinfo/diskinfo.c:
	- If the DIOCGPHYSPATH ioctl is successful, report physical path
	  data when diskinfo is executed with the '-v' option.

Submitted by:	will
Reviewed by:	gibbs
Sponsored by:	Spectra Logic Corporation

Add generic attribute change notification support to GEOM.

sys/sys/geom/geom.h:
	Add a new attrchanged method field to both g_class
	and g_geom.

sys/sys/geom/geom.h:
sys/geom/geom_event.c:
	- Provide the g_attr_changed() function that providers
	  can use to advertise attribute changes.
	- Perform delivery of attribute change notifications
	  from a thread context via the standard GEOM event
	  mechanism.

sys/geom/geom_subr.c:
	Inherit the attrchanged method from class to geom (class instance).

sys/geom/geom_disk.c:
	Provide disk_attr_changed() to provide g_attr_changed() access
	to consumers of the disk API.

sys/cam/scsi/scsi_pass.c:
sys/cam/scsi/scsi_da.c:
sys/geom/geom_dev.c:
sys/geom/geom_disk.c:
	Use attribute changed events to track updates to physical path
	information.

sys/cam/scsi/scsi_da.c:
	Add AC_ADVINFO_CHANGED to the registered asynchronous CAM
	events for this driver.  When this event occurs, and
	the updated buffer type references our physical path
	attribute, emit a GEOM attribute changed event via the
	disk_attr_changed() API.

sys/cam/scsi/scsi_pass.c:
	Add AC_ADVINFO_CHANGED to the registered asynchronous CAM
	events for this driver.  When this event occurs, update
	the physical patch devfs alias for this pass instance.

Submitted by:	gibbs
Sponsored by:	Spectra Logic Corporation
2011-06-14 17:10:32 +00:00
gibbs
19d8ec29e2 Lay groundwork in CAM for recording and reporting physical path and
other device attributes stored in the CAM Existing Device Table (EDT).
This includes some infrastructure requried by the enclosure services
driver to export physical path information.

Make the CAM device advanced info interface accept store requests.

  sys/cam/scsi/scsi_all.c:
  sys/cam/scsi/scsi_all.h:
	- Replace scsi_get_sas_addr() with a scsi_get_devid() which takes
	  a callback that decides whether to accept a particular descriptor.
	  Provide callbacks for NAA IEEE Registered addresses and for SAS
	  addresses, replacing the old function.  This is needed because
	  the old function doesn't work for an enclosure address for a SAS
	  device, which is not flagged as a SAS address, but is NAA IEEE
	  Registered.  It may be worthwhile merging this interface with the
	  devid match interface.
	- Add a few more defines for some device ID fields.

  sbin/camcontrol/camcontrol.c:
	- Update for the CCB_DEV_ADVINFO interface change.

  cam/cam_xpt_internal.h:
	- Add the new fields for the physical path string to the CAM EDT.
  cam/cam_ccb.h:
	- Rename CCB_GDEV_ADVINFO to simply CCB_DEV_ADVINFO, and the ccb
	  structure to ccb_dev_advinfo.
	- Add a flag that changes this CCB's action to store, rather than
	  the default, retrieve.
	- Add a new buffer type, CDAI_TYPE_PHYS_PATH, for the new CAM EDT
	  physpath field.
	- Remove the never-implemented transport & proto flags.
  cam/cam_xpt.c:
  cam/cam_xpt.h:
	- Add xpt_getattr(), which provides a wrapper for fetching a device's
	  attribute using the GEOM strings as key.  This method currently
	  supports "GEOM::ident" and "GEOM::physpath".

Submitted by: will
Reviewed by : gibbs

Extend the XPT_DEV_MATCH api to allow a device search by device ID.
As far as the API is concerned, device ID is a binary blob to be
interpreted by the transport layer.  The SCSI implementation assumes
it is an array of VPD device ID descriptors.

  sys/cam/cam_ccb.h:
	Create a new structure, device_id_match_pattern, and
	update the XPT_DEV_MATCH datastructures and flags so
	that this pattern type can be used.

  sys/cam/cam_xpt.c:
	- A single pattern matching on both inquiry data and device
	  ID is invalid.  Report any violators.
	- Pass device ID match requests through to the new routine
	  scsi_devid_match().  The direct call of a SCSI routine is
	  a layering violation, but no worse than the one a few
	  lines up that checks inquiry data.  Defer cleaning this
	  up until our future, larger, rototilling of CAM.
	- Zero out cam_ed and cam_et nodes on allocation.  Prior to
	  this change, device_id_len and device_id were not inialized,
	  preventing proper detection of the presence of this
	  information.

  sys/cam/scsi/scsi_all.c:
  sys/cam/scsi/scsi_all.h:
	Add the scsi_match_devid() routine.

Add a helper function for extracting peripherial driver names

  sys/cam/cam_periph.c:
  sys/cam/cam_periph.h:
	Add the cam_periph_list() method which fills an sbuf
	with a comma delimited list of the peripheral instances
	associated with a given CAM path.

Add a helper functions for SCSI commands used by the SES driver.

  sys/cam/scsi/scsi_all.c:
  sys/cam/scsi/scsi_all.h:
	Add structure definitions and csio filling functions for
	the receive diagnostic results and send diagnostic commands.

Misc CAM XPT cleanups.

  sys/cam/cam_xpt.c:
	Broadcast AC_FOUND_DEVICE and AC_PATH_REGISTERED
	events at the time async event handlers are attached
	even when registering just for events on a partitular
	SIM.  Previously, you had to register for these
	events on all SIMs in the system in order to get
	the initial broadcast even though subsequent device
	and path arrivals would be delivered.

  sys/cam/cam_xpt.c:
	Remove SIM mutex held asserts from path accessors.
	CAM paths are reference counted and it is this
	reference count, not the sim mutex, that garantees
	they are stable.

Sponsored by: Spectra Logic Corporation
2011-06-14 14:53:17 +00:00
mav
9bc238fc03 Make CAM report devices with ATA/SATA transport to devstat(9) as IDE. 2011-04-14 21:25:32 +00:00
ken
ff1d787db7 Fix a few issues related to the XPT_GDEV_ADVINFO CCB.
camcontrol.c:	In buildbusdevlist(), don't attempt to get call
		getdevid() for an unconfigured device, even when the
		verbose flag is set.  The cam_open_btl() call will almost
		certainly fail.

		Probe for the buffer size when issuing the XPT_GDEV_ADVINFO
		CCB.  Probing for the buffer size first helps us avoid
		allocating the maximum buffer size when it really may not
		be necessary.  This also helps avoid errors from
		cam_periph_mapmem() if we attempt to map more than MAXPHYS.

cam_periph.c:	In cam_periph_mapmem(), if the XPT_GDEV_ADVINFO CCB
		shows a bufsiz of 0, we don't have anything to map,
		so just return.

		Also, set the maximum mapping size to MAXPHYS
		instead of DFLTPHYS for XPT_GDEV_ADVINFO CCBs,
		since they don't actually go down to the hardware.

scsi_pass.c:	Don't bother mapping the buffer in XPT_GDEV_ADVINFO
		CCBs if bufsiz is 0.
2010-12-10 21:38:51 +00:00
ken
7f0ccdf947 Add Serial Management Protocol (SMP) passthrough support to CAM.
This includes support in the kernel, camcontrol(8), libcam and the mps(4)
driver for SMP passthrough.

The CAM SCSI probe code has been modified to fetch Inquiry VPD page 0x00
to determine supported pages, and will now fetch page 0x83 in addition to
page 0x80 if supported.

Add two new CAM CCBs, XPT_SMP_IO, and XPT_GDEV_ADVINFO.  The SMP CCB is
intended for SMP requests and responses.  The ADVINFO is currently used to
fetch cached VPD page 0x83 data from the transport layer, but is intended
to be extensible to fetch other types of device-specific data.

SMP-only devices are not currently represented in the CAM topology, and so
the current semantics are that the SIM will route SMP CCBs to either the
addressed device, if it contains an SMP target, or its parent, if it
contains an SMP target.  (This is noted in cam_ccb.h, since it will change
later once we have the ability to have SMP-only devices in CAM's topology.)

smp_all.c,
smp_all.h:		New helper routines for SMP.  This includes
			SMP request building routines, response parsing
			routines, error decoding routines, and structure
			definitions for a number of SMP commands.

libcam/Makefile:	Add smp_all.c to libcam, so that SMP functionality
			is available to userland applications.

camcontrol.8,
camcontrol.c:		Add smp passthrough support to camcontrol.  Several
			new subcommands are now available:

			'smpcmd' functions much like 'cmd', except that it
			allows the user to send generic SMP commands.

			'smprg' sends the SMP report general command, and
			displays the decoded output.  It will automatically
			fetch extended output if it is available.

			'smppc' sends the SMP phy control command, with any
			number of potential options.  Among other things,
			this allows the user to reset a phy on a SAS
			expander, or disable a phy on an expander.

			'smpmaninfo' sends the SMP report manufacturer
			information and displays the decoded output.

			'smpphylist' displays a list of phys on an
			expander, and the CAM devices attached to those
			phys, if any.

cam.h,
cam.c:			Add a status value for SMP errors
			(CAM_SMP_STATUS_ERROR).

			Add a missing description for CAM_SCSI_IT_NEXUS_LOST.

			Add support for SMP commands to cam_error_string().

cam_ccb.h:		Rename the CAM_DIR_RESV flag to CAM_DIR_BOTH.  SMP
			commands are by nature bi-directional, and we may
			need to support bi-directional SCSI commands later.

			Add the XPT_SMP_IO CCB.  Since SMP commands are
			bi-directional, there are pointers for both the
			request and response.

			Add a fill routine for SMP CCBs.

			Add the XPT_GDEV_ADVINFO CCB.  This is currently
			used to fetch cached page 0x83 data from the
			transport later, but is extensible to fetch many
			other types of data.

cam_periph.c:		Add support in cam_periph_mapmem() for XPT_SMP_IO
			and XPT_GDEV_ADVINFO CCBs.

cam_xpt.c:		Add support for executing XPT_SMP_IO CCBs.

cam_xpt_internal.h:	Add fields for VPD pages 0x00 and 0x83 in struct
			cam_ed.

scsi_all.c:		Add scsi_get_sas_addr(), a function that parses
			VPD page 0x83 data and pulls out a SAS address.

scsi_all.h:		Add VPD page 0x00 and 0x83 structures, and a
			prototype for scsi_get_sas_addr().

scsi_pass.c:		Add support for mapping buffers in XPT_SMP_IO and
			XPT_GDEV_ADVINFO CCBs.

scsi_xpt.c:		In the SCSI probe code, first ask the device for
			VPD page 0x00.  If any VPD pages are supported,
			that page is required to be implemented.  Based on
			the response, we may probe for the serial number
			(page 0x80) or device id (page 0x83).

			Add support for the XPT_GDEV_ADVINFO CCB.

sys/conf/files:		Add smp_all.c.

mps.c:			Add support for passing in a uio in mps_map_command(),
			so we can map a S/G list at once.

			Add support for SMP passthrough commands in
			mps_data_cb().  SMP is a special case, because the
			first buffer in the S/G list is outbound and the
			second buffer is inbound.

			Add support for warning the user if the busdma code
			comes back with more buffers than will work for the
			command.  This will, for example, help the user
			determine why an SMP command failed if busdma comes
			back with three buffers.

mps_pci.c:		Add sys/uio.h.

mps_sas.c:		Add the SAS address and the parent handle to the
			list of fields we pull from device page 0 and cache
			in struct mpssas_target.  These are needed for SMP
			passthrough.

			Add support for the XPT_SMP_IO CCB.  For now, this
			CCB is routed to the addressed device if it supports
			SMP, or to its parent if it does not and the parent
			does.  This is necessary because CAM does not
			currently support SMP-only nodes in the topology.

			Make SMP passthrough support conditional on
			__FreeBSD_version >= 900026.  This will make it
			easier to MFC this change to the driver without
			MFCing the CAM changes as well.

mps_user.c:		Un-staticize mpi_init_sge() so we can use it for
			the SMP passthrough code.

mpsvar.h:		Add a uio and iovecs into struct mps_command for
			SMP passthrough commands.

			Add a cm_max_segs field to struct mps_command so
			that we can warn the user if busdma comes back with
			too many segments.

			Clear the cm_reply when a command gets freed.  If
			it is not cleared, reply frames will eventually get
			freed into the pool multiple times and corrupt the
			pool.  (This fix is from scottl.)

			Add a prototype for mpi_init_sge().

sys/param.h:		Bump __FreeBSD_version to 900026 for the for the
			inclusion of the XPT_GDEV_ADVINFO and XPT_SMP_IO
			CAM CCBs.
2010-11-30 22:39:46 +00:00
mdf
e9f1044ef2 Use destroy_dev_sched(9) instead of destroy_dev(9) in passcleanup() as
it is indirectly a d_close method.

Prompted by:	kib
Reviewed by:	mav
MFC after:	2 weeks
2010-09-20 19:42:14 +00:00
mav
72062fdcec 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.
2010-01-28 08:41:30 +00:00
scottl
e33e5dce32 Separate the parallel scsi knowledge out of the core of the XPT, and
modularize it so that new transports can be created.

Add a transport for SATA

Add a periph+protocol layer for ATA

Add a driver for AHCI-compliant hardware.

Add a maxio field to CAM so that drivers can advertise their max
I/O capability.  Modify various drivers so that they are insulated
from the value of MAXPHYS.

The new ATA/SATA code supports AHCI-compliant hardware, and will override
the classic ATA driver if it is loaded as a module at boot time or compiled
into the kernel.  The stack now support NCQ (tagged queueing) for increased
performance on modern SATA drives.  It also supports port multipliers.

ATA drives are accessed via 'ada' device nodes.  ATAPI drives are
accessed via 'cd' device nodes.  They can all be enumerated and manipulated
via camcontrol, just like SCSI drives.  SCSI commands are not translated to
their ATA equivalents; ATA native commands are used throughout the entire
stack, including camcontrol.  See the camcontrol manpage for further
details.  Testing this code may require that you update your fstab, and
possibly modify your BIOS to enable AHCI functionality, if available.

This code is very experimental at the moment.  The userland ABI/API has
changed, so applications will need to be recompiled.  It may change
further in the near future.  The 'ada' device name may also change as
more infrastructure is completed in this project.  The goal is to
eventually put all CAM busses and devices until newbus, allowing for
interesting topology and management options.

Few functional changes will be seen with existing SCSI/SAS/FC drivers,
though the userland ABI has still changed.  In the future, transports
specific modules for SAS and FC may appear in order to better support
the topologies and capabilities of these technologies.

The modularization of CAM and the addition of the ATA/SATA modules is
meant to break CAM out of the mold of being specific to SCSI, letting it
grow to be a framework for arbitrary transports and protocols.  It also
allows drivers to be written to support discrete hardware without
jeopardizing the stability of non-related hardware.  While only an AHCI
driver is provided now, a Silicon Image driver is also in the works.
Drivers for ICH1-4, ICH5-6, PIIX, classic IDE, and any other hardware
is possible and encouraged.  Help with new transports is also encouraged.

Submitted by:	scottl, mav
Approved by:	re
2009-07-10 08:18:08 +00:00