Commit Graph

11 Commits

Author SHA1 Message Date
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
scottl
74448961ec Add a helper function for registering async callbacks. Besides
eliminating a lot of duplicated code, this also fixes a locking edge case.
2007-05-16 16:54:23 +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
5688edd003 Add an xpt_rescan function and a thread that will field
rescan requests. The purpose of this is to allow a SIM
(or other entities) to request a bus rescan and have it
then fielded in a different (process) context from the
caller.

There are probably better ways to accomplish this, but
it's a very small change that helps solve a number of
problems.

Reviewed by:	Justin, Ken and Scott.
MFC after:	2 weeks
2007-02-23 05:47:36 +00:00
mjacob
18ed122eed Add an xpt_print function to reduce most of the xpt_print_path/printf
pairs. Convert the core code to use it.

Reviewed by:	scsi (various folks weighing in with good advice)
MFC after:	2 weeks
2006-12-05 07:45:28 +00:00
imp
362fcfc1e2 Start each of the license/copyright comments with /*- 2005-01-05 22:34:37 +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
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
peter
3b842d34e8 $Id$ -> $FreeBSD$ 1999-08-28 01:08:13 +00:00
gibbs
855593c295 CAM Transport Layer (XPT).
Submitted by:	The CAM Team
1998-09-15 06:33:23 +00:00