Commit Graph

91 Commits

Author SHA1 Message Date
mav
b24d810911 MFp4:
- Extend XPT-SIM transfer settings control API. Now it allows to report to
SATA SIM number of tags supported by each device, implement ATA mode and
SATA revision negotiation for both SATA and PATA SIMs.
- Make ahci(4) and siis(4) to use submitted maximum tag number, when
scheduling requests. It allows to support NCQ on devices with lower tags
count then controller supports.
- Make PMP driver to report attached devices connection speeds.
- Implement ATA mode negotiation between user settings, device and
controller capabilities.
2009-11-24 12:47:58 +00:00
mav
17cadb1aa5 MFp4:
- Move tagged queueing control from ADA to ATA XPT. It allows to control
  device command queue length correctly. First step to support < 32 tags.
- Limit queue for non-tagged devices by 2 slots for ahci(4) and siis(4).
- Implement quirk matching for ATA devices.
- Move xpt_schedule_dev_sendq() from header to source file.
- Move delayed queue shrinking to the more expected place - element freeing.
- Remove some SCSIsms in ATA.
2009-11-11 11:10:36 +00:00
mav
924c32a1e2 MFp4:
- Reduce code duplication in ATA XPT and PMP driver.
- Move PIO size setting from ada driver to ATA XPT. It is XPT business
to negotiate transfer details. ada driver is now stateless.
- Report PIO size to SIM. It is required for correct PATA SIM operation.
- Tune PMP scan timings. It workarounds some problems with SiI.
- If reset hapens during PMP initialization - restart it.
- Introduce early-initialized periph drivers, which are used during initial
scan process. Use it for xpt, probe, aprobe and pmp. It gives pmp chance
to finish scan before mountroot and numerate devices in right order.
2009-10-31 10:43:38 +00:00
mav
d0dca34aa6 Fix iSCSI initiator and vpo driver operation, broken by CAM changes.
Reviewed by:	scottl, Danny Braniss
Approved by:	re (rwatson)
2009-08-18 08:46:54 +00:00
mjacob
2d4b24984c Add 8Gb support (isp_2500). Fix a fair number of configuration and
firmware loading bugs.

Target mode support has received some serious attention to make it
more usable and stable.

Some backward compatible additions to CAM have been made that make
target mode async events easier to deal with have also been put
into place.

Further refinement and better support for NP-IV (N-port Virtualization)
is now in place.

Code for release prior to RELENG_7 has been stripped away for code clarity.

Sponsored by: Copan Systems

Reviewed by:    scottl, ken, jung-uk kim
Approved by:    re
2009-08-01 01:04:26 +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
scottl
7605c12c0f 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
mjacob
2a86bf8073 Remove CTS_SPI_FLAGS_TAG_ENB. Nobody is using it and at least one
author can't remember why it was there.

The CTS_SCSI_FLAGS_TAG_ENB remains in place, and makes sense, and is
checked all over the place.

The CTS_SPI_FLAGS_TAG_ENB was probably an attempt to distinguish
protocol and transport tag capabilities. At the very least this can
be confusing and prone to many bugs, so let's just assume that the
transport tag case just flows from the protocol (and vice versa)
for now.
2006-12-03 07:19:28 +00:00
mjacob
19b599de4a 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
mjacob
3917690ec7 Add PIM_SEQSCAN for HBA misc flags and code that understands
what to do with it.

This forces us to scan targets sequentially, not in parallel.
The reason we might want to do this is that SPI negotiation
might not work right at the SIM level if we try to do it
in parallel. We *could* fix this for each SIM where this is
broken, but it's a lot harder to do that when we can simply
ask CAM to probe sequentially.

If PIM_SEQSCAN is not set (default), the original behaviour for
probing is unchanged.

LUN probing is still done in parallel for each target in either
case.

While we're at it, clean up some resource leakage for error
cases.

Reviewed by:	ken, scott, scsi@
MFC after:	1 week
2006-06-05 22:22:14 +00:00
mjacob
434c60ccbb Sorry- last delta was checked in by mistake. 2006-05-24 15:23:27 +00:00
mjacob
7c7ebb01c6 Make physical buffers in cam_periph_mapmem owned by the kernel in case we
return to user space w/o waiting for I/O to complete.

I tried to get several folks who know this code better than me to review it
with no luck. I *do* know that w/o this code, using the SCSI target driver
panics in userret (if it doesn't panic in knote first).
2006-05-24 15:22:21 +00:00
mjacob
d8f173b52a CAM_NEW_TRAN_CODE placeholders for SAS support.
Reviewed by:	nate, ken, justin
MFC after:	1 month
2006-01-20 19:21:38 +00:00
imp
362fcfc1e2 Start each of the license/copyright comments with /*- 2005-01-05 22:34:37 +00:00
scottl
a866680c8a Reformat the comments for cam_hdr so that they can be read. 2004-06-07 19:12:44 +00:00
njl
1cd634adc1 Add a PATH_INQ flag, PIM_NO_6_BYTE, which indicates the SIM never wishes to
receive 6 byte commands.  Add a check for this flag to da(4) and cd(4) so
that they honor it.  This is a quick workaround for many devices (especially
USB) that require da(4) quirks to operate.  The more complete approach is
to finish the new transport code which will be aware of the SCSI version a
transport implements.

MFC after:	1 day
2003-07-28 06:15:59 +00:00
njl
b184633199 Merge common XPT_CALC_GEOMETRY functions into a single convenience function.
Devices below may experience a change in geometry.

* Due to a bug, aic(4) never used extended geometry.  Changes all drives
  >1G to now use extended translation.
* sbp(4) drives exactly 1 GB in size now no longer use extended geometry.
* umass(4) drives exactly 1 GB in size now no longer use extended geometry.

For all other controllers in this commit, this should be a no-op.

PR:
Submitted by:
Looked over by:	scottl
Approved by:
Obtained from:
MFC after:
2003-06-14 22:17:38 +00:00
ken
3c97032a19 Add support to CAM for devices with more than 2^32 blocks. (2TB if you're
using 512 byte blocks).

cam_ccb.h:	Bump up volume_size and cylinders in ccb_calc_geometry to
		64 bits and 32 bits respectively, so we can hold larger
		device sizes.  cylinders would overflow at about 500GB.
		Bump CAM_VERSION for this change.  Note that this will
		require a recompile of all applications that talk to the
		pass(4) driver.

scsi_all.c:	Add descriptions for READ/WRITE(16), update READ/WRITE(12)
		descriptions, add descriptions for SERVICE ACTION IN/OUT.
		Add a new function, scsi_read_capacity_16(), that issues
		the read capacity service action.  (Necessary for arrays
		larger than 2^32 sectors.)  Update scsi_read_write() to use
		a 64 bit LBA and issue READ(16) or WRITE(16) if necessary.
		NOTE the API change.  This should be largely transparnet
		to most userland applications at compile time, but will
		break binary compatibility.  The CAM_VERSION bump, above,
		also serves the purpose of forcing a recompile for any
		applications that talk to CAM.

scsi_all.h:	Add 16 byte READ/WRITE structures, structures for 16 byte
		READ CAPACITY/SERVICE ACTION IN.  Add scsi_u64to8b() and
		scsi_8btou64.

scsi_da.c:	The da(4) driver probe now has two stages for devices
		larger than 2TB.  If a standard READ CAPACITY(10) returns
		0xffffffff, we issue the 16 byte version of read capacity
		to determine the true array capacity.  We also do the same
		thing in daopen() -- use the 16 byte read capacity if the
		device is large enough.

		The sysctl/loader code has also been updated to accept
		16 bytes as a minimum command size.
2003-04-30 00:35:22 +00:00
kan
9468fdaf14 Deprecate machine/limits.h in favor of new sys/limits.h.
Change all in-tree consumers to include <sys/limits.h>

Discussed on:	standards@
Partially submitted by: Craig Rodrigues <rodrigc@attbi.com>
2003-04-29 13:36:06 +00:00
mjacob
f4263fe731 Add a transport settings variant for Fibre Channel. 2001-06-24 18:17:45 +00:00
mjacob
989a523fa8 first blush at some FC path inquiry settings 2001-06-04 18:08:30 +00:00
ken
24c4b1e75b Rewrite of the CAM error recovery code.
Some of the major changes include:

	- The SCSI error handling portion of cam_periph_error() has
	  been broken out into a number of subfunctions to better
	  modularize the code that handles the hierarchy of SCSI errors.
	  As a result, the code is now much easier to read.

	- String handling and error printing has been significantly
	  revamped.  We now use sbufs to do string formatting instead
	  of using printfs (for the kernel) and snprintf/strncat (for
	  userland) as before.

	  There is a new catchall error printing routine,
	  cam_error_print() and its string-based counterpart,
	  cam_error_string() that allow the kernel and userland
	  applications to pass in a CCB and have errors printed out
	  properly, whether or not they're SCSI errors.  Among other
	  things, this helped eliminate a fair amount of duplicate code
	  in camcontrol.

	  We now print out more information than before, including
	  the CAM status and SCSI status and the error recovery action
	  taken to remedy the problem.

	- sbufs are now available in userland, via libsbuf.  This
	  change was necessary since most of the error printing code
	  is shared between libcam and the kernel.

	- A new transfer settings interface is included in this checkin.
	  This code is #ifdef'ed out, and is primarily intended to aid
	  discussion with HBA driver authors on the final form the
	  interface should take.  There is example code in the ahc(4)
	  driver that implements the HBA driver side of the new
	  interface.  The new transfer settings code won't be enabled
	  until we're ready to switch all HBA drivers over to the new
	  interface.

src/Makefile.inc1,
lib/Makefile:		Add libsbuf.  It must be built before libcam,
			since libcam uses sbuf routines.

libcam/Makefile:	libcam now depends on libsbuf.

libsbuf/Makefile:	Add a makefile for libsbuf.  This pulls in the
			sbuf sources from sys/kern.

bsd.libnames.mk:	Add LIBSBUF.

camcontrol/Makefile:	Add -lsbuf.  Since camcontrol is statically
			linked, we can't depend on the dynamic linker
			to pull in libsbuf.

camcontrol.c:		Use cam_error_print() instead of checking for
			CAM_SCSI_STATUS_ERROR on every failed CCB.

sbuf.9:			Change the prototypes for sbuf_cat() and
			sbuf_cpy() so that the source string is now a
			const char *.  This is more in line wth the
			standard system string functions, and helps
			eliminate warnings when dealing with a const
			source buffer.

			Fix a typo.

cam.c:			Add description strings for the various CAM
			error status values, as well as routines to
			look up those strings.

			Add new cam_error_string() and
			cam_error_print() routines for userland and
			the kernel.

cam.h:			Add a new CAM flag, CAM_RETRY_SELTO.

			Add enumerated types for the various options
			available with cam_error_print() and
			cam_error_string().

cam_ccb.h:		Add new transfer negotiation structures/types.

			Change inq_len in the ccb_getdev structure to
			be "reserved".  This field has never been
			filled in, and will be removed when we next
			bump the CAM version.

cam_debug.h:		Fix typo.

cam_periph.c:		Modularize cam_periph_error().  The SCSI error
			handling part of cam_periph_error() is now
			in camperiphscsistatuserror() and
			camperiphscsisenseerror().

			In cam_periph_lock(), increase the reference
			count on the periph while we wait for our lock
			attempt to succeed so that the periph won't go
			away while we're sleeping.

cam_xpt.c:		Add new transfer negotiation code.  (ifdefed
			out)

			Add a new function, xpt_path_string().  This
			is a string/sbuf analog to xpt_print_path().

scsi_all.c:		Revamp string handing and error printing code.
			We now use sbufs for much of the string
			formatting code.  More of that code is shared
			between userland the kernel.

scsi_all.h:		Get rid of SS_TURSTART, it wasn't terribly
			useful in the first place.

			Add a new error action, SS_REQSENSE.  (Send a
			request sense and then retry the command.)
			This is useful when the controller hasn't
			performed autosense for some reason.

			Change the default actions around a bit.

scsi_cd.c,
scsi_da.c,
scsi_pt.c,
scsi_ses.c:		SF_RETRY_SELTO -> CAM_RETRY_SELTO.  Selection
			timeouts shouldn't be covered by a sense flag.

scsi_pass.[ch]:		SF_RETRY_SELTO -> CAM_RETRY_SELTO.

			Get rid of the last vestiges of a read/write
			interface.

libkern/bsearch.c,
sys/libkern.h,
conf/files:		Add bsearch.c, which is needed for some of the
			new table lookup routines.

aic7xxx_freebsd.c:	Define AHC_NEW_TRAN_SETTINGS if
			CAM_NEW_TRAN_CODE is defined.

sbuf.h,
subr_sbuf.c:		Add the appropriate #ifdefs so sbufs can
			compile and run in userland.

			Change sbuf_printf() to use vsnprintf()
			instead of kvprintf(), which is only available
			in the kernel.

			Change the source string for sbuf_cpy() and
			sbuf_cat() to be a const char *.

			Add __BEGIN_DECLS and __END_DECLS around
			function prototypes since they're now exported
			to userland.

kdump/mkioctls:		Include stdio.h before cam.h since cam.h now
			includes a function with a FILE * argument.

Submitted by:	gibbs (mostly)
Reviewed by:	jdp, marcel (libsbuf makefile changes)
Reviewed by:	des (sbuf changes)
Reviewed by:	ken
2001-03-27 05:45:52 +00:00
gibbs
ce75b526ee cam_ccb.h:
Bring back the CAM_NEGOTIATE ccb flag.  This flag indicates
	that SPI transfer negotiation should occur concurrently with the
	execution of this CCB.  The flag is not yet used by the XPT but
	is required for proper support of multi-initiator configurations
	where topology scans cannot rely on a bus reset to invalidate
	prior negotiations.

cam_xpt.c:
	Don't allow DT transmission rates to be specified for devices
	that don't have the DT feature listed in their inquiry data.
2000-07-18 19:47:14 +00:00
jake
961b97d434 Back out the previous change to the queue(3) interface.
It was not discussed and should probably not happen.

Requested by:		msmith and others
2000-05-26 02:09:24 +00:00
jake
d93fbc9916 Change the way that the queue(3) structures are declared; don't assume that
the type argument to *_HEAD and *_ENTRY is a struct.

Suggested by:	phk
Reviewed by:	phk
Approved by:	mdodd
2000-05-23 20:41:01 +00:00
n_hibma
c79db87671 Various typo's.
One minor nit. The speed was displayed wrong when below 1Mb/s.
2000-03-15 21:55:48 +00:00
mjacob
0ca52ef8b9 Because we added 4 bytes to the inquiry data size, we need to
rev the CAM revision too. Tsk.
Submitted by:	ken@freebsd.org
2000-01-25 21:24:52 +00:00
mjacob
84d60a5744 Shift bits for CAM flags so that the top bit isn't set in an enum
(at request of Ken Merry). Garbage collect items out of the ccb_getdev
structure and and a length field so that consumes will know how much
of the inq_data tag is valid. Clean up a few misspellings. Add
a CAM_SEND_STATUS target mode flag.

All of this necessitated a CAM_VERSION bump.

JHK approved.

Reviewed by:	gibbs@freebsd.org, ken@freebsd.org
2000-01-17 06:15:35 +00:00
mjacob
d1d5787ce4 Widen width of tag && initiator ids to u_int
(from u_int8_t) in ccb_accept_tio structure. This
matches usage elsewhere and also allows me to
overload the tag id with the RX_ID for fibre
channel target mode.
Reviewed by:	gibbs@freebsd.org
2000-01-03 08:54:51 +00:00
peter
d53e4c1d80 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.
1999-12-29 05:07:58 +00:00
ken
f491f5dd58 Get rid of some trailing commas in enumerated types that cause gcc to
complain when some warnings are turned on.

Requested by:	Bertrand Petit <elrond@phoe.frmug.org>
1999-11-17 05:06:52 +00:00
peter
3b842d34e8 $Id$ -> $FreeBSD$ 1999-08-28 01:08:13 +00:00
gibbs
83b4c498f6 Bump CAM version number. 1999-08-16 23:18:24 +00:00
gibbs
0d50de05e5 Add another command characteristic flag for commands that are queued
on physical devices as oposed to just in the XPT.  This is used to
mark XPT_SCSI_IO, XPT_RESET_DEV, XPT_ENG_EXEC, XPT_TARGET_IO, and
XPT_CONT_TARGET_IO function codes.

Change tag_id and init_id to be u_int from u_int8_t.  Some topologies
supported by CAM support much larger ID and tag ID address spaces
than parallel SCSI.

Kill some unused fields in the IMMED_NOTIFY ccb type.
1999-08-16 22:14:47 +00:00
gibbs
95e29ded40 Rely on the statistics in XPT_GDEV_STATS instead of the versions still
retained in XPT_GDEV_TYPE for binary compatibility.  Mark the legacy
structure values for removal when we bump the major CAM revision.
1999-05-23 18:57:29 +00:00
gibbs
95dc85b099 Add the XPT_PATH_STATS and XPT_GDEV_STATS function codes. These ccb
types allow the reporting of error counts and other statistics.  Currently
we provide information on the last BDR or bus reset as well as active
transaction inforamtion, but this will be expanded as more information is
added to aid in error recovery.

Use the 'last reset' information to better handle bus settle delays.
Peripheral drivers now control whether a bus settle delay occurs and
for how long.  This allows target mode peripheral drivers to avoid
having their device queue frozen by the XPT for what shoudl only be
initiator type behavior.

Don't perform a bus reset if the target device is incapable of performing
transfer negotiation (e.g. Fiber Channel).

If we don't perform a bus reset but the controller is capable of transfer
negotiations, force negotiations on the first transaction to go to the
device.  This ensures that we aren't tripped up by a left over negotiation
from the prom, BIOS, loader, etc.

Add a default async handler funstion to cam_periph.c to remove duplicated
code in all initiator type peripheral drivers.

Allow mapping of XPT_CONT_TARGET_IO ccbs from userland.  They are
itentical to XPT_SCSI_IO ccbs as far as data mapping is concerned.
1999-05-22 21:58:47 +00:00
ken
2bb789d7a3 Add a number of interrelated CAM feature enhancements and bug fixes.
NOTE:  These changes will require recompilation of any userland
applications, like cdrecord, xmcd, etc., that use the CAM passthrough
interface.  A make world is recommended.

camcontrol.[c8]:
 - We now support two new commands, "tags" and "negotiate".

	- The tags commands allows users to view the number of tagged
	  openings for a device as well as a number of other related
	  parameters, and it allows users to set tagged openings for
	  a device.

	- The negotiate command allows users to enable and disable
	  disconnection and tagged queueing, set sync rates, offsets
	  and bus width.  Note that not all of those features are
	  available for all controllers.  Only the adv, ahc, and ncr
	  drivers fully support all of the features at this point.
	  Some cards do not allow the setting of sync rates, offsets and
	  the like, and some of the drivers don't have any facilities to
	  do so.  Some drivers, like the adw driver, only support enabling
	  or disabling sync negotiation, but do not support setting sync
	  rates.

 - new description in the camcontrol man page of how to format a disk
 - cleanup of the camcontrol inquiry command
 - add support in the 'devlist' command for skipping unconfigured devices if
   -v was not specified on the command line.
 - make use of the new base_transfer_speed in the path inquiry CCB.
 - fix CCB bzero cases

cam_xpt.c, cam_sim.[ch], cam_ccb.h:

 - new flags on many CCB function codes to designate whether they're
   non-immediate, use a user-supplied CCB, and can only be passed from
   userland programs via the xpt device.  Use these flags in the transport
   layer and pass driver to categorize CCBs.

 - new flag in the transport layer device matching code for device nodes
   that indicates whether a device is unconfigured

 - bump the CAM version from 0x10 to 0x11

 - Change the CAM ioctls to use the version as their group code, so we can
   force users to recompile code even when the CCB size doesn't change.

 - add + fill in a new value in the path inquiry CCB, base_transfer_speed.
   Remove a corresponding field from the cam_sim structure, and add code to
   every SIM to set this field to the proper value.

 - Fix the set transfer settings code in the transport layer.

scsi_cd.c:

 - make some variables volatile instead of just casting them in various
   places
 - fix a race condition in the changer code
 - attach unless we get a "logical unit not supported" error.  This should
   fix all of the cases where people have devices that return weird errors
   when they don't have media in the drive.

scsi_da.c:

 - attach unless we get a "logical unit not supported" error

scsi_pass.c:

 - for immediate CCBs, just malloc a CCB to send the user request in.  This
   gets rid of the 'held' count problem in camcontrol tags.

scsi_pass.h:

 - change the CAM ioctls to use the CAM version as their group code.

adv driver:

 - Allow changing the sync rate and offset separately.

adw driver

 - Allow changing the sync rate and offset separately.

aha driver:

 - Don't return CAM_REQ_CMP for SET_TRAN_SETTINGS CCBs.

ahc driver:

 - Allow setting offset and sync rate separately

bt driver:

 - Don't return CAM_REQ_CMP for SET_TRAN_SETTINGS CCBs.

NCR driver:

 - Fix the ultra/ultra 2 negotiation bug
 - allow setting both the sync rate and offset separately

Other HBA drivers:
 - Put code in to set the base_transfer_speed field for
   XPT_GET_TRAN_SETTINGS CCBs.

Reviewed by:	gibbs, mjacob (isp), imp (aha)
1999-05-06 20:16:39 +00:00
gibbs
a18208654b Add constants and macros for dealing with XPT opcode group types. 1999-03-05 23:13:20 +00:00
gibbs
d4b7c14a09 Expand the hba_misc fied in the Path Inquiry ccb to allow a controller driver
to specify that it does not provide initiator services (PIM_NOINITIATOR)
and that the initial bus reset for device probing should be avoided
(PIM_NOBUSRESET).

Modify the XPT layer to honor these flags.
1998-12-10 04:05:49 +00:00
gibbs
391b30cdfa Add a mechanism to send a non-tagged transaction even if a device is
currently operating in a tagged mode.  The SIM driver should determine
if a device is in tag mode by looking at the CAM_TAG_ACTION_VALID flag
in the ccb header.  If the flag is set, the tag_action field is either
a SCSI II tag message (simple, ordered, head) or CAM_TAG_ACTION_NONE
to specify that no tagging should be performed.
1998-10-15 23:17:35 +00:00
gibbs
855593c295 CAM Transport Layer (XPT).
Submitted by:	The CAM Team
1998-09-15 06:33:23 +00:00