- 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.
attachment of new devices that arrive (and we notice them
via async Fibre Channel events). We've always had the
right thing (of sorts) happen when devices go away- this
is the corollary function that makes multipath failover
actually work.
MFC after: 2 weeks
holders. The license that was approved for my changes to this driver
originally came from LSI, but the changes to the driver core are not
owned by LSI.
MFC: 1 day
o Add timeout error recovery (from a thread context to avoid
the deferral of other critical interrupts).
o Properly recover commands across controller reset events.
o Update the driver to handle events and status codes that
have been added to the MPI spec since the driver was
originally written.
o Make the driver more modular to improve maintainability and
support dynamic "personality" registration (e.g. SCSI Initiator,
RAID, SAS, FC, etc).
o Shorten and simplify the common I/O path to improve driver
performance.
o Add RAID volume and RAID member state/settings reporting.
o Add periodic volume resynchronization status reporting.
o Add support for sysctl tunable resync rate, member write cache
enable, and volume transaction queue depth.
Sponsored by
----------------
Avid Technologies Inc:
SCSI error recovery, driver re-organization, update of MPI library
headers, portions of dynamic personality registration, and misc bug
fixes.
Wheel Open Technologies:
RAID event notification, RAID member pass-thru support, firmware
upload/download support, enhanced RAID resync speed, portions
of dynamic personality registration, and misc bug fixes.
Detailed Changes
================
mpt.c mpt_cam.c mpt_raid.c mpt_pci.c:
o Add support for personality modules. Each module exports
load, and unload module scope methods as well as probe, attach,
event, reset, shutdown, and detach per-device instance
methods
mpt.c mpt.h mpt_pci.c:
o The driver now associates a callback function (via an
index) with every transaction submitted to the controller.
This allows the main interrupt handler to absolve itself
of any knowledge of individual transaction/response types
by simply calling the callback function "registered" for
the transaction. We use a callback index instead of a
callback function pointer in each requests so we can
properly handle responses (e.g. event notifications)
that are not associated with a transaction. Personality
modules dynamically register their callbacks with the
driver core to receive the callback index to use for their
handlers.
o Move the interrupt handler into mpt.c. The ISR algorithm
is bus transport and OS independent and thus had no reason
to be in mpt_pci.c.
o Simplify configuration message reply handling by copying
reply frame data for the requester and storing completion
status in the original request structure.
o Add the mpt_complete_request_chain() helper method and use
it to implement reset handlers that must abort transactions.
o Keep track of all pending requests on the new
requests_pending_list in the softc.
o Add default handlers to mpt.c to handle generic event
notifications and controller reset activities. The event
handler code is largely the same as in the original driver.
The reset handler is new and terminates any pending transactions
with a status code indicating the controller needs to be
re-initialized.
o Add some endian support to the driver. A complete audit is
still required for this driver to have any hope of operating
in a big-endian environment.
o Use inttypes.h and __inline. Come closer to being style(9)
compliant.
o Remove extraneous use of typedefs.
o Convert request state from a strict enumeration to a series
of flags. This allows us to, for example, tag transactions
that have timed-out while retaining the state that the
transaction is still in-flight on the controller.
o Add mpt_wait_req() which allows a caller to poll or sleep
for the completion of a request. Use this to simplify
and factor code out from many initialization routines.
We also use this to sleep for task management request
completions in our CAM timeout handler.
mpt.c:
o Correct a bug in the event handler where request structures were
freed even if the request reply was marked as a continuation
reply. Continuation replies indicate that the controller still owns
the request and freeing these replies prematurely corrupted
controller state.
o Implement firmware upload and download. On controllers that do
not have dedicated NVRAM (as in the Sun v20/v40z), the firmware
image is downloaded to the controller by the system BIOS. This
image occupies precious controller RAM space until the host driver
fetches the image, reducing the number of concurrent I/Os the
controller can processes. The uploaded image is used to
re-program the controller during hard reset events since the
controller cannot fetch the firmware on its own. Implementing this
feature allows much higher queue depths when RAID volumes
are configured.
o Changed configuration page accessors to allow threads to sleep
rather than busy wait for completion.
o Removed hard coded data transfer sizes from configuration page
routines so that RAID configuration page processing is possible.
mpt_reg.h:
o Move controller register definitions into a separate file.
mpt.h:
o Re-arrange includes to allow inlined functions to be
defined in mpt.h.
o Add reply, event, and reset handler definitions.
o Add softc fields for handling timeout and controller
reset recovery.
mpt_cam.c:
o Move mpt_freebsd.c to mpt_cam.c. Move all core functionality,
such as event handling, into mpt.c leaving only CAM SCSI
support here.
o Revamp completion handler to provide correct CAM status for
all currently defined SCSI MPI message result codes.
o Register event and reset handlers with the MPT core. Modify
the event handler to notify CAM of bus reset events. The
controller reset handler will abort any transactions that
have timed out. All other pending CAM transactions are
correctly aborted by the core driver's reset handler.
o Allocate a single request up front to perform task management
operations. This guarantees that we can always perform a
TMF operation even when the controller is saturated with other
operations. The single request also serves as a perfect
mechanism of guaranteeing that only a single TMF is in flight
at a time - something that is required according to the MPT
Fusion documentation.
o Add a helper function for issuing task management requests
to the controller. This is used to abort individual requests
or perform a bus reset.
o Modify the CAM XPT_BUS_RESET ccb handler to wait for and
properly handle the status of the bus reset task management
frame used to reset the bus. The previous code assumed that
the reset request would always succeed.
o Add timeout recovery support. When a timeout occurs, the
timed-out request is added to a queue to be processed by
our recovery thread and the thread is woken up. The recovery
thread processes timed-out command serially, attempting first
to abort them and then falling back to a bus reset if an
abort fails.
o Add calls to mpt_reset() to reset the controller if any
handshake command, bus reset attempt or abort attempt
fails due to a timeout.
o Export a secondary "bus" to CAM that exposes all volume drive
members as pass-thru devices, allowing CAM to perform proper
speed negotiation to hidden devices.
o Add a CAM async event handler tracking the AC_FOUND_DEVICE event.
Use this to trigger calls to set the per-volume queue depth once
the volume is fully registered with CAM. This is required to avoid
hitting firmware limits on volume queue depth. Exceeding the
limit causes the firmware to hang.
mpt_cam.h:
o Add several helper functions for interfacing to CAM and
performing timeout recovery.
mpt_pci.c:
o Disable interrupts on the controller before registering and
enabling interrupt delivery to the OS. Otherwise we risk
receiving interrupts before the driver is ready to receive
them.
o Make use of compatibility macros that allow the driver to
be compiled under 4.x and 5.x.
mpt_raid.c:
o Add a per-controller instance RAID thread to perform settings
changes and query status (minimizes CPU busy wait loops).
o Use a shutdown handler to disable "Member Write Cache Enable"
(MWCE) setting for RAID arrays set to enable MWCE During Rebuild.
o Change reply handler function signature to allow handlers to defer
the deletion of reply frames. Use this to allow the event reply
handler to queue up events that need to be acked if no resources
are available to immediately ack an event. Queued events are
processed in mpt_free_request() where resources are freed. This
avoids a panic on resource shortage.
o Parse and print out RAID controller capabilities during driver probe.
o Define, allocate, and maintain RAID data structures for volumes,
hidden member physical disks and spare disks.
o Add dynamic sysctls for per-instance setting of the log level, array
resync rate, array member cache enable, and volume queue depth.
mpt_debug.c:
o Add mpt_lprt and mpt_lprtc for printing diagnostics conditioned on
a particular log level to aid in tracking down driver issues.
o Add mpt_decode_value() which parses the bits in an integer
value based on a parsing table (mask, value, name string, tuples).
mpilib/*:
o Update mpi library header files to latest distribution from LSI.
Submitted by: gibbs
Approved by: re