CAM. This can significantly improve performance particularly for SSDs
which don't suffer from seek latencies.
The sysctl / tunable kern.cam.sort_io_queues provides the systems default
setting where:-
0 = queued BIOs are NOT sorted
1 = queued BIOs are sorted (default)
Each device gets its own sysctl kern.cam.<type>.<id>.sort_io_queue
Valid values are:-
-1 = use system default (default)
0 = queued BIOs are NOT sorted
1 = queued BIOs are sorted
Note: Additional patch will look to add automatic use of none sorted queues
for none rotating media e.g. SSD's
Reviewed by: scottl
Approved by: pjd (mentor)
MFC after: 2 weeks
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.
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
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.
- 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.
- 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.
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
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
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.
