There are certain rogue devices (and the aic7xxx driver) that return
BUSY or QUEUE_FULL forever.  This code will apply a global timeout (of
the total number of retries times the per command timer) to a given
command.  If it is exceeded, the command is completed regardless of its
state.

The patch also removes the unused field in the command: timeout and
timeout_total.

This solves the problem of detecting an endless loop in the mid-layer
because of BUSY/QUEUE_FULL bouncing, but will not recover the device.
In the aic7xxx case, the driver can be recovered by sending a bus reset,
so possibly this should be tied into the error handler?
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

We never look at it except for the old megaraid driver that abuses it
for sending internal commands.  That usage can be fixed easily because
those internal commands are single-threaded by a mutex and we can easily
use a completion there.
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

never checked anywhere
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

Never used for anything but printing it out in debug routines.
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

it's never set to anything, and just three broken drivers are looking
at it and doing odd things.
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

scsi_cmnd->serial_number_at_timeout doesn't serve any purpose
anymore.  All serial_number == serial_number_at_timeout tests
are always true in abort callbacks.  Kill the field.  Also, as
->pid always equals ->serial_number and ->serial_number
doesn't have any special meaning anymore, update comments
above ->serial_number accordingly.  Once we remove all uses of
this field from all lldd's, this field should go.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

scsi_cmnd->internal_timeout field doesn't have any meaning
anymore.  Kill the field.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

scsi_cmnd->serial_number_at_timeout doesn't serve any purpose
anymore.  All serial_number == serial_number_at_timeout tests
are always true in abort callbacks.  Kill the field.  Also, as
->pid always equals ->serial_number and ->serial_number
doesn't have any special meaning anymore, update comments
above ->serial_number accordingly.  Once we remove all uses of
this field from all lldd's, this field should go.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

scsi_cmnd->internal_timeout field doesn't have any meaning
anymore.  Kill the field.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!