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.
Remove "???" from T_IT8_1/2. They actually are pre-press devices for graphic arts as described by ASC IT8
Zeros and blanks scsipi_inquiry_data from byte 58 to byte 74 if additional_length is less than 58
statically. Since this function may called for another luns immediately,
allocating it statically doesn't make sense and may cause race condition
as pointed out by PR#9749.
- `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.
FC loops). Change the semantics of scsi_probedev so that it returns 1 if
you should continue probing at this target, else 0 for not.
Replace the blanket use of '7' with the use of the new sc_maxlun property
that is now gathered from HBAs. Allocate scsipi_link arrays based upon this.
Fix a really nasty and silly bug that has been there for a while where the
number of first level scsipi_link structures was one less than it needed
to be.
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).
Implement ioctl pass-through to the host bus adapter, allowing both
SCBUS* ioctls handled at that level and host adapter-specific ioctls
to be implemented. Implement SCBUSIORESET as a pass-through.
Inspired by PR #6090, from Matt Jacob.
pk