using the ahc driver hang when probing scsi devices. The problem may be in
the ahc driver and not in this change, but back it out until this has been
fixed anyway.
called via a callout, kick the completion thread to run it for us (uses
a new flag, SCSIPI_CHAN_KICK).
If we've received BUSY status and we haven't started the completion
thread yet, don't freeze do a callout to scsipi_periph_timed_thaw which
then will try and kick the completion thread- instead treat the command
as if it were a polled command and just call delay for 1 second.
If DIAGNOSTIC is defined, and the periph qfreeze count is less than
zero, panic because some HBA has corrupted the periph structure's
accounting.
not present" don't print any message but still return ENODEV.
Use this in cd driver to allow open of character raw partition even if
the drive is empty (older drives fails at LOAD_UNLOAD time, newer
ones fail at TEST_UNIT_READY time).
This is a completely rewritten scsipi_xfer execution engine, and the
associated changes to HBA drivers. Overview of changes & features:
- All xfers are queued in the mid-layer, rather than doing so in an
ad-hoc fashion in individual adapter drivers.
- Adapter/channel resource management in the mid-layer, avoids even trying
to start running an xfer if the adapter/channel doesn't have the resources.
- Better communication between the mid-layer and the adapters.
- Asynchronous event notification mechanism from adapter to mid-layer and
peripherals.
- Better peripheral queue management: freeze/thaw, sorted requeueing during
recovery, etc.
- Clean separation of peripherals, adapters, and adapter channels (no more
scsipi_link).
- Kernel thread for each scsipi_channel makes error recovery much easier
(no more dealing with interrupt context when recovering from an error).
- Mid-layer support for tagged queueing: commands can have the tag type
set explicitly, tag IDs are allocated in the mid-layer (thus eliminating
the need to use buggy tag ID allocation schemes in many adapter drivers).
- support for QUEUE FULL and CHECK CONDITION status in mid-layer; the command
will be requeued, or a REQUEST SENSE will be sent as appropriate.
Just before the merge syssrc has been tagged with thorpej_scsipi_beforemerge
it when considering whether to attach devices. This is to facilitate
`non-SCSI' RAID controller drivers that want to provide SCSI pass-through
services to the kernel.
timeout()/untimeout() API:
- Clients supply callout handle storage, thus eliminating problems of
resource allocation.
- Insertion and removal of callouts is constant time, important as
this facility is used quite a lot in the kernel.
The old timeout()/untimeout() API has been removed from the kernel.
- `flags' is now gone, replaced with `xs_control' and `xs_status'.
- Massive cleanup of the control flags. Now we explicitly say that
a job is to complete asynchronously, rather than relying on side-effects,
and use a new flag to now that device discovery is being performed.
- Do SCSI device discovery interrupt-driven.
- the cap field is a u_int8_t, so none of the defined flags would fit in.
Looks like nobody had a drive using 16 bytes commands.
- the ACAP_DRQ_* flags are all wrong. Just remove them and use the definitions
from ata/atareg.h, there's no need to duplicate theses. The effect of this
was that we were always polling for the command phase, even for drives
with interrupt DRQ. This didn't break until the code was changed to support
shared interrupts.
Should fix the lookup problems or 'boot hangs' reported by some users, and
kern/7111.
"device_q" TAILQ entries. The former is for use by the adapter driver,
as it sees fit. The latter is for the scsipi middle layer to track
pending xfers per device.
- Add a pending_xfers queue to scsipi_link, to track pending xfers per
device.
- Grow scsipi_link's flags to int, and add SDEV_WAITDRAIN, to indicate that
we're waiting for the pending_xfers queue to empty.
scsi_base.c to scsipi_base.c. Rename the functions from scsi_verbose.c
too, and rename the file itself. Cleaup includes too (scsi_*.h should not
be #included in scsipi_*.h files, which are supposed to be
common to atapi and scsi).
struct scsipi_adapter; they were not used.
Add a scsipi_ioctl entry point to struct scsipi_adapter. This will be
used to issue ioctl commands to the host adapters.
Inspired by PR #6090, from Matt Jacob.
scsipi_xfer structures.
When scsipi_execute_xs() calls the driver's scsi_cmd function, it assumes
that it can still dereference a pointer to the scsipi_xfer struct. Since
scsipi_done() has already been called, which in turn has called
scsipi_free_xs(), the struct has already been returned the structure to
the pool! In other words, xs->flags has been compromised, but we are still
testing it.
These changes resolve the problem by doing the following:
- In scsipi_execute_xs(), if the hardware driver's scsi_cmd function
returns SUCCESSFULLY_QUEUED, set a new flag (SCSI_ASYNCREQ) in xs->flags.
Since the request will be handled asynchronously, we will need the
scsipi_xfer struct to be freed in scsipi_done().
If the hardware driver's scsi_cmd function returns COMPLETE, we now
simply return any actual errors, or 0 if none occurred. (Previously,
we may have returned EJUSTRETURN, of which the sole effect was to
avoid freeing the scsipi_xfer struct in our caller.)
- In scsipi_done(), only free the scsipi_xfer struct for async requests.
The contents of the struct will otherwise remain valid until the
function that initiated the transfer frees it.
With this change, responsibility for freeing the struct now lies in two
places, depending on the type of the request:
- For synchronous requests, the routine calling scsipi_execute_xs()
must clean up.
- For asynchronous requests, scsipi_done() cleans up (as it always has).
[Note: this change also corrects a problem with sddump(): scsipi_done()
was attempting to return a static scsipi_xfer struct to the pool! Since
dumps are performed synchronously, we now handle this correctly.]
This solution was provided by Jason Thorpe, after I got him to look at
some related (but insufficient) attempts of my own.
-store printable product ID in cd's and sd's softc, use it as "typename"
-for this, add a "destination buffer length" argument to scsipi_strvis()
-return ATAPI device type for ATAPI devices
