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66 Commits

Author SHA1 Message Date
Alexander Motin
6f954fb36b Remove MAXBSIZE use from drivers where it has nothing to do.
In some cases limits are just not needed, in others -- DFLTPHYS is the
right constant to use instead.

MFC after:	1 month
2015-03-22 16:10:28 +00:00
Steven Hartland
85c9dd9d89 Prevent overflow issues in timeout processing
Previously, any timeout value for which (timeout * hz) will overflow the
signed integer, will give weird results, since callout(9) routines will
convert negative values of ticks to '1'. For unsigned integer overflow we
will get sufficiently smaller timeout values than expected.

Switch from callout_reset, which requires conversion to int based ticks
to callout_reset_sbt to avoid this.

Also correct isci to correctly resolve ccb timeout.

This was based on the original work done by Eygene Ryabinkin
<rea@freebsd.org> back in 5 Aug 2011 which used a macro to help avoid
the overlow.

Differential Revision:	https://reviews.freebsd.org/D1157
Reviewed by:	mav, davide
MFC after:	1 month
Sponsored by:	Multiplay
2014-11-21 21:01:24 +00:00
John Baldwin
7ff829cb0e Lock iir(4) and mark it MPSAFE.
- Add a per-device mutex to the softc and use it for bus_dma tags,
  CAM SIMs, callouts, and interrupt handler.
- Switch from timeout(9) to callout(9).
- Add a separate global mutex to protect the global event buffer ring.
- Return completed index from iir_intr_locked() and remove the global
  gdt_wait_* variables.
- Remove global list of gdt softcs and replace its use with
  devclass_get_device().
- Use si_drv1 to store softc pointer in the SDEV_PER_HBA case instead
  of minor numbers.
- Do math on osreldate instead of dubious char math on osrelease[]
  that didn't work on 10.0+.
- Use bus_*() instead of bus_space_*().
- Use device_printf() instead of printf() with a unit number.

Tested by:	no one
2014-11-13 22:00:18 +00:00
Scott Long
eb8a7632ba 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 17:16:21 +00:00
Glen Barber
0082e54e9d Revert r255853 pending fixes to build errors in usr.bin/kdump
Approved by:	re (implicit)
2013-09-25 01:48:45 +00:00
Scott Long
185884259b 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
Jung-uk Kim
bd00cfe2c8 Avoid potential redefinition of the macro. 2013-08-15 20:03:22 +00:00
Konstantin Belousov
dd0b4fb6d5 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
Juli Mallett
f1bd1e9dd7 Remove comments about creating DMA tags as children of the DMA tags of their
parent bus where the code has now been modified to do so.

Reviewed by:	scottl
2012-03-12 19:29:32 +00:00
Scott Long
b6f97155cc Convert a number of drivers to obtaining their parent DMA tag from their
PCI device attachment.
2012-03-12 08:03:51 +00:00
Ed Schouten
d745c852be Mark MALLOC_DEFINEs static that have no corresponding MALLOC_DECLAREs.
This means that their use is restricted to a single C file.
2011-11-07 06:44:47 +00:00
Kenneth D. Merry
1cc052e80f Add descriptor sense support to CAM, and honor sense residuals properly in
CAM.

Desriptor sense is a new sense data format that originated in SPC-3.  Among
other things, it allows for an 8-byte info field, which is necessary to
pass back block numbers larger than 4 bytes.

This change adds a number of new functions to scsi_all.c (and therefore
libcam) that abstract out most access to sense data.

This includes a bump of CAM_VERSION, because the CCB ABI has changed.
Userland programs that use the CAM pass(4) driver will need to be
recompiled.

camcontrol.c:	Change uses of scsi_extract_sense() to use
		scsi_extract_sense_len().

		Use scsi_get_sks() instead of accessing sense key specific
		data directly.

scsi_modes:	Update the control mode page to the latest version (SPC-4).

scsi_cmds.c,
scsi_target.c:	Change references to struct scsi_sense_data to struct
		scsi_sense_data_fixed.  This should be changed to allow the
		user to specify fixed or descriptor sense, and then use
		scsi_set_sense_data() to build the sense data.

ps3cdrom.c:	Use scsi_set_sense_data() instead of setting sense data
		manually.

cam_periph.c:	Use scsi_extract_sense_len() instead of using
		scsi_extract_sense() or accessing sense data directly.

cam_ccb.h:	Bump the CAM_VERSION from 0x15 to 0x16.  The change of
		struct scsi_sense_data from 32 to 252 bytes changes the
		size of struct ccb_scsiio, but not the size of union ccb.
		So the version must be bumped to prevent structure
		mis-matches.

scsi_all.h:	Lots of updated SCSI sense data and other structures.

		Add function prototypes for the new sense data functions.

		Take out the inline implementation of scsi_extract_sense().
		It is now too large to put in a header file.

		Add macros to calculate whether fields are present and
		filled in fixed and descriptor sense data

scsi_all.c:	In scsi_op_desc(), allow the user to pass in NULL inquiry
		data, and we'll assume a direct access device in that case.

		Changed the SCSI RESERVED sense key name and description
		to COMPLETED, as it is now defined in the spec.

		Change the error recovery action for a number of read errors
		to prevent lots of retries when the drive has said that the
		block isn't accessible.  This speeds up reconstruction of
		the block by any RAID software running on top of the drive
		(e.g. ZFS).

		In scsi_sense_desc(), allow for invalid sense key numbers.
		This allows calling this routine without checking the input
		values first.

		Change scsi_error_action() to use scsi_extract_sense_len(),
		and handle things when invalid asc/ascq values are
		encountered.

		Add a new routine, scsi_desc_iterate(), that will call the
		supplied function for every descriptor in descriptor format
		sense data.

		Add scsi_set_sense_data(), and scsi_set_sense_data_va(),
		which build descriptor and fixed format sense data.  They
		currently default to fixed format sense data.

		Add a number of scsi_get_*() functions, which get different
		types of sense data fields from either fixed or descriptor
		format sense data, if the data is present.

		Add a number of scsi_*_sbuf() functions, which print
		formatted versions of various sense data fields.  These
		functions work for either fixed or descriptor sense.

		Add a number of scsi_sense_*_sbuf() functions, which have a
		standard calling interface and print the indicated field.
		These functions take descriptors only.

		Add scsi_sense_desc_sbuf(), which will print a formatted
		version of the given sense descriptor.

		Pull out a majority of the scsi_sense_sbuf() function and
		put it into scsi_sense_only_sbuf().  This allows callers
		that don't use struct ccb_scsiio to easily utilize the
		printing routines.  Revamp that function to handle
		descriptor sense and use the new sense fetching and
		printing routines.

		Move scsi_extract_sense() into scsi_all.c, and implement it
		in terms of the new function, scsi_extract_sense_len().
		The _len() version takes a length (which should be the
		sense length - residual) and can indicate which fields are
		present and valid in the sense data.

		Add a couple of new scsi_get_*() routines to get the sense
		key, asc, and ascq only.

mly.c:		Rename struct scsi_sense_data to struct
		scsi_sense_data_fixed.

sbp_targ.c:	Use the new sense fetching routines to get sense data
		instead of accessing it directly.

sbp.c:		Change the firewire/SCSI sense data transformation code to
		use struct scsi_sense_data_fixed instead of struct
		scsi_sense_data.  This should be changed later to use
		scsi_set_sense_data().

ciss.c:		Calculate the sense residual properly.  Use
		scsi_get_sense_key() to fetch the sense key.

mps_sas.c,
mpt_cam.c:	Set the sense residual properly.

iir.c:		Use scsi_set_sense_data() instead of building sense data by
		hand.

iscsi_subr.c:	Use scsi_extract_sense_len() instead of grabbing sense data
		directly.

umass.c:	Use scsi_set_sense_data() to build sense data.

		Grab the sense key using scsi_get_sense_key().

		Calculate the sense residual properly.

isp_freebsd.h:	Use scsi_get_*() routines to grab asc, ascq, and sense key
		values.

		Calculate and set the sense residual.

MFC after:	3 days
Sponsored by:	Spectra Logic Corporation
2011-10-03 20:32:55 +00:00
Edward Tomasz Napierala
5de96da8e3 Get rid of #ident. 2010-01-08 20:40:28 +00:00
Edward Tomasz Napierala
d8a9f5a9d9 Remove unused iir_watchdog().
Reviewed by:	scottl
2010-01-08 15:47:23 +00:00
Marcel Moolenaar
44979e8d7a Include <sys/sysctl.h>, to get the declarations of ostype and
osrelease. Remove the duplicate declarations from this file.
2009-12-02 20:24:37 +00:00
Poul-Henning Kamp
6778431478 Revert previous commit and add myself to the list of people who should
know better than to commit with a cat in the area.
2009-09-08 13:19:05 +00:00
Poul-Henning Kamp
b34421bf9c Add necessary include. 2009-09-08 13:16:55 +00:00
John Baldwin
8985d7f35e Remove unused VM includes. 2009-06-03 20:25:13 +00:00
Warner Losh
00b4e54ae7 We no longer need to use d_thread_t, migrate to struct thread *. 2009-05-20 17:29:21 +00:00
Christian Brueffer
3af3ff479b Compare the correct variable against NULL.
Reviewed by:	scottl
Found with:	Coverity Prevent(tm)
CID:		821
MFC after:	2 weeks
2009-05-14 13:32:33 +00:00
Ed Schouten
6bfa9a2d66 Replace all calls to minor() with dev2unit().
After I removed all the unit2minor()/minor2unit() calls from the kernel
yesterday, I realised calling minor() everywhere is quite confusing.
Character devices now only have the ability to store a unit number, not
a minor number. Remove the confusion by using dev2unit() everywhere.

This commit could also be considered as a bug fix. A lot of drivers call
minor(), while they should actually be calling dev2unit(). In -CURRENT
this isn't a problem, but it turns out we never had any problem reports
related to that issue in the past. I suspect not many people connect
more than 256 pieces of the same hardware.

Reviewed by:	kib
2008-09-27 08:51:18 +00:00
Scott Long
15d0222f66 Fix a buffer overflow in the processing of various SCSI commands. This likely
fixes a an great number of weird problems that have been reported with this
driver.

PR: 119114
Submitted by: Jens Rehsack
2008-01-09 20:02:56 +00:00
Scott Long
b50569b71d 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.
2007-06-17 05:55:54 +00:00
Scott Long
2b83592fdc Remove Giant from CAM. Drivers (SIMs) now register a mutex that CAM will
use to synchornize and protect all data objects that are used for that
SIM.  Drivers that are not yet MPSAFE register Giant and operate as
usual.  RIght now, no drivers are MPSAFE, though a few will be changed
in the coming week as this work settles down.

The driver API has changed, so all CAM drivers will need to be recompiled.
The userland API has not changed, so tools like camcontrol do not need to
be recompiled.
2007-04-15 08:49:19 +00:00
Paolo Pisati
ef544f6312 o break newbus api: add a new argument of type driver_filter_t to
bus_setup_intr()

o add an int return code to all fast handlers

o retire INTR_FAST/IH_FAST

For more info: http://docs.freebsd.org/cgi/getmsg.cgi?fetch=465712+0+current/freebsd-current

Reviewed by: many
Approved by: re@
2007-02-23 12:19:07 +00:00
Matt Jacob
b3d93fd0c9 Add MODULE_DEPENDS for cam, pci, mca, eisa and isa where needed.
PR:		106543
MFC after:	3 days
2006-12-11 18:28:31 +00:00
Matt Jacob
bd3fd815a7 2nd and final commit that moves us to CAM_NEW_TRAN_CODE
as the default.

Reviewed by multitudes.
2006-11-02 00:54:38 +00:00
Matt Jacob
fa9ed86506 The first of 3 major steps to move the CAM layer forward to using
the CAM_NEW_TRAN_CODE that has been in the tree for some years now.

This first step consists solely of adding to or correcting
CAM_NEW_TRAN_CODE pieces in the kernel source tree such
that a both a GENERIC (at least on i386) and a LINT build
with CAM_NEW_TRAN_CODE as an option will compile correctly
and run (at least with some the h/w I have).

After a short settle time, the other pieces (making
CAM_NEW_TRAN_CODE the default and updating libcam
and camcontrol) will be brought in.

This will be an incompatible change in that the size of structures
related to XPT_PATH_INQ and XPT_{GET,SET}_TRAN_SETTINGS change
in both size and content. However, basic system operation and
basic system utilities work well enough with this change.

Reviewed by:	freebsd-scsi and specific stakeholders
2006-10-31 05:53:29 +00:00
Poul-Henning Kamp
c40da00ca3 Since DELAY() was moved, most <machine/clock.h> #includes have been
unnecessary.
2006-05-16 14:37:58 +00:00
Scott Long
3469383f4f Big update to the iir driver:
- Don't use a common buffer in the softc to store per-command data.  Reserve
  a buffer in the command itself.
- Don't allocate DMA memory for the kernel command structures when all you
  really need is DMA memory for the scratch buffer embedded in them.  Instead
  allocate a slab for the scratch buffers and divide it up as needed.
- Call bus_dmamap_unload() at the completion of commands.
- Preserve and clear the CAM CCB status flags at completion.
- Reorder some low-level command operations to try to close races.
- Limit the simq to 32 commands for now.  There are some serious problems
  with the driver under load that are not well understood, so keeping the
  simq lower helps avoid this.  It has been tested at a higher value, but
  this is a safe value that doesn't show much performance degredation.

These changes allow the driver to work reliably with >4GB of memory on i386
and amd64, and also work around deadlocks seen under very high load in
certain situations.  The work-around is far from ideal, but without and
documentation it is hard to know what the right fix is.

MFC candidate
2006-03-01 07:24:39 +00:00
Robert Watson
04fe37f68e Convert iir inlines to ANSI C function declarations.
MFC after:	1 week
2006-01-21 19:56:19 +00:00
Yoshihiro Takahashi
d4fcf3cba5 Remove bus_{mem,p}io.h and related code for a micro-optimization on i386
and amd64.  The optimization is a trivial on recent machines.

Reviewed by:	-arch (imp, marcel, dfr)
2005-05-29 04:42:30 +00:00
Colin Percival
c340af03a0 Correct improper permissions on /dev/iir. The earlier permissions
of 0644 allowed for people to do Evil Things via ioctl(2).

Security: FreeBSD-SA-05:06.iir
2005-05-06 02:33:46 +00:00
Warner Losh
b77e575e1d Use BUS_PROBE_DEFAULT for pci probe return value 2005-03-05 18:17:35 +00:00
Joerg Wunsch
a5f50ef9e4 netchild's mega-patch to isolate compiler dependencies into a central
place.

This moves the dependency on GCC's and other compiler's features into
the central sys/cdefs.h file, while the individual source files can
then refer to #ifdef __COMPILER_FEATURE_FOO where they by now used to
refer to #if __GNUC__ > 3.1415 && __BARC__ <= 42.

By now, GCC and ICC (the Intel compiler) have been actively tested on
IA32 platforms by netchild.  Extension to other compilers is supposed
to be possible, of course.

Submitted by:	netchild
Reviewed by:	various developers on arch@, some time ago
2005-03-02 21:33:29 +00:00
Scott Long
9e521c8906 Remove a dead vtophys() reference. 2005-01-31 01:26:22 +00:00
Warner Losh
098ca2bda9 Start each of the license/copyright comments with /*-, minor shuffle of lines 2005-01-06 01:43:34 +00:00
Scott Long
21b1acfb93 Panic if given a CAM_DATA_PHYS pointer from CAM instead of trying to handle it.
It makes no sense in a PAE environment and is impossible to handle correctly.
This case is also never used right now.  This should make the iir(4) driver
ready for PAE.
2004-09-03 08:44:23 +00:00
Poul-Henning Kamp
89c9c53da0 Do the dreaded s/dev_t/struct cdev */
Bump __FreeBSD_version accordingly.
2004-06-16 09:47:26 +00:00
Scott Long
7cb88a352e Update from vendor. This also adds support for newer management tools.
Submitted by:	Achim Leubner
2004-05-19 17:46:34 +00:00
Scott Long
fa2ed23667 Fix the ioctl types for two ioctls. I'm not sure if the switch was my
fault or the vendor's fault when I brought in rev 1.5.  This allows
the 'storcon' utility to work again.

Sponsored by:	freebsdsystems.com
2004-03-20 19:02:46 +00:00
Nate Lawson
5f96beb9e0 Convert callers to the new bus_alloc_resource_any(9) API.
Submitted by:	Mark Santcroos <marks@ripe.net>
Reviewed by:	imp, dfr, bde
2004-03-17 17:50:55 +00:00
Tom Rhodes
a122cca953 These are changes to allow to use the Intel C/C++ compiler (lang/icc)
to build the kernel. It doesn't affect the operation if gcc.

Most of the changes are just adding __INTEL_COMPILER to #ifdef's, as
icc v8 may define __GNUC__ some parts may look strange but are
necessary.

Additional changes:
 - in_cksum.[ch]:
   * use a generic C version instead of the assembly version in the !gcc
     case (ASM code breaks with the optimizations icc does)
     -> no bad checksums with an icc compiled kernel
     Help from:		andre, grehan, das
     Stolen from: 	alpha version via ppc version
     The entire checksum code should IMHO be replaced with the DragonFly
     version (because it isn't guaranteed future revisions of gcc will
     include similar optimizations) as in:
        ---snip---
          Revision  Changes    Path
          1.12      +1 -0      src/sys/conf/files.i386
          1.4       +142 -558  src/sys/i386/i386/in_cksum.c
          1.5       +33 -69    src/sys/i386/include/in_cksum.h
          1.5       +2 -0      src/sys/netinet/igmp.c
          1.6       +0 -1      src/sys/netinet/in.h
          1.6       +2 -0      src/sys/netinet/ip_icmp.c

          1.4       +3 -4      src/contrib/ipfilter/ip_compat.h
          1.3       +1 -2      src/sbin/natd/icmp.c
          1.4       +0 -1      src/sbin/natd/natd.c
          1.48      +1 -0      src/sys/conf/files
          1.2       +0 -1      src/sys/conf/files.amd64
          1.13      +0 -1      src/sys/conf/files.i386
          1.5       +0 -1      src/sys/conf/files.pc98
          1.7       +1 -1      src/sys/contrib/ipfilter/netinet/fil.c
          1.10      +2 -3      src/sys/contrib/ipfilter/netinet/ip_compat.h
          1.10      +1 -1      src/sys/contrib/ipfilter/netinet/ip_fil.c
          1.7       +1 -1      src/sys/dev/netif/txp/if_txp.c
          1.7       +1 -1      src/sys/net/ip_mroute/ip_mroute.c
          1.7       +1 -2      src/sys/net/ipfw/ip_fw2.c
          1.6       +1 -2      src/sys/netinet/igmp.c
          1.4       +158 -116  src/sys/netinet/in_cksum.c
          1.6       +1 -1      src/sys/netinet/ip_gre.c
          1.7       +1 -2      src/sys/netinet/ip_icmp.c
          1.10      +1 -1      src/sys/netinet/ip_input.c
          1.10      +1 -2      src/sys/netinet/ip_output.c
          1.13      +1 -2      src/sys/netinet/tcp_input.c
          1.9       +1 -2      src/sys/netinet/tcp_output.c
          1.10      +1 -1      src/sys/netinet/tcp_subr.c
          1.10      +1 -1      src/sys/netinet/tcp_syncache.c
          1.9       +1 -2      src/sys/netinet/udp_usrreq.c

          1.5       +1 -2      src/sys/netinet6/ipsec.c
          1.5       +1 -2      src/sys/netproto/ipsec/ipsec.c
          1.5       +1 -1      src/sys/netproto/ipsec/ipsec_input.c
          1.4       +1 -2      src/sys/netproto/ipsec/ipsec_output.c

          and finally remove
            sys/i386/i386        in_cksum.c
            sys/i386/include     in_cksum.h
        ---snip---
 - endian.h:
   * DTRT in C++ mode
 - quad.h:
   * we don't use gcc v1 anymore, remove support for it
   Suggested by:	bde (long ago)
 - assym.h:
   * avoid zero-length arrays (remove dependency on a gcc specific
     feature)
     This change changes the contents of the object file, but as it's
     only used to generate some values for a header, and the generator
     knows how to handle this, there's no impact in the gcc case.
   Explained by:	bde
   Submitted by:	Marius Strobl <marius@alchemy.franken.de>
 - aicasm.c:
   * minor change to teach it about the way icc spells "-nostdinc"
   Not approved by:	gibbs (no reply to my mail)
 - bump __FreeBSD_version (lang/icc needs to know about the changes)

Incarnations of this patch survive gcc compiles since a loooong time,
I use it on my desktop. An icc compiled kernel works since Nov. 2003
(exceptions: snd_* if used as modules), it survives a build of the
entire ports collection with icc.

Parts of this commit contains suggestions or submissions from
Marius Strobl <marius@alchemy.franken.de>.

Reviewed by:	-arch
Submitted by:	netchild
2004-03-12 21:45:33 +00:00
Poul-Henning Kamp
dc08ffec87 Device megapatch 4/6:
Introduce d_version field in struct cdevsw, this must always be
initialized to D_VERSION.

Flip sense of D_NOGIANT flag to D_NEEDGIANT, this involves removing
four D_NOGIANT flags and adding 145 D_NEEDGIANT flags.
2004-02-21 21:10:55 +00:00
Scott Long
444dbd3802 Remove the static major assignment for iir(4).
Submitted by:	phk (partially)
2004-02-14 23:18:58 +00:00
Scott Long
50e2aaa00c Update email addresses, copyrights, and tweak the management interface.
Submitted by: "Leubner, Achim" <Achim_Leubner@adaptec.com>
2003-09-26 15:36:47 +00:00
John Baldwin
e27951b29c Use PCIR_BAR(x) instead of PCIR_MAPS.
Glanced over by:	imp, gibbs
Tested by:		i386 LINT
2003-09-02 17:30:40 +00:00
David E. O'Brien
aad970f1fe Use __FBSDID().
Also some minor style cleanups.
2003-08-24 17:55:58 +00:00
Warner Losh
77e6a3b2dd Prefer new location of pci include files (which have only been in the
tree for two or more years now), except in a few places where there's
code to be compatible with older versions of FreeBSD.
2003-08-22 06:00:27 +00:00
Scott Long
f6b1c44d1f Mega busdma API commit.
Add two new arguments to bus_dma_tag_create(): lockfunc and lockfuncarg.
Lockfunc allows a driver to provide a function for managing its locking
semantics while using busdma.  At the moment, this is used for the
asynchronous busdma_swi and callback mechanism.  Two lockfunc implementations
are provided: busdma_lock_mutex() performs standard mutex operations on the
mutex that is specified from lockfuncarg.  dftl_lock() is a panic
implementation and is defaulted to when NULL, NULL are passed to
bus_dma_tag_create().  The only time that NULL, NULL should ever be used is
when the driver ensures that bus_dmamap_load() will not be deferred.
Drivers that do not provide their own locking can pass
busdma_lock_mutex,&Giant args in order to preserve the former behaviour.

sparc64 and powerpc do not provide real busdma_swi functions, so this is
largely a noop on those platforms.  The busdma_swi on is64 is not properly
locked yet, so warnings will be emitted on this platform when busdma
callback deferrals happen.

If anyone gets panics or warnings from dflt_lock() being called, please
let me know right away.

Reviewed by:	tmm, gibbs
2003-07-01 15:52:06 +00:00