By setting the request_limit in send_srp_login to 1 we allowed login
requests to be sent to the server adapter.  If this was not an initial
login, but was a login after a disconnect with the server, other I/O
requests could attempt to be processed before the login occured.  These
I/O requests would fail, sometimes resulting in filesystems getting
marked read-only.

To address this we can set the request_limit to 0 while doing the login
and add an exception where login requests, along with task management
events, are always passed to the server.

There is a case where the request_limit had already reached 0 would result
in all events being sent rather than returning SCSI_MLQUEUE_HOST_BUSY; this
has also been fixed by this patch.
Signed-off-by: NRobert Jennings <rcj@linux.vnet.ibm.com>
Signed-off-by: NBrian King <brking@linux.vnet.ibm.com>
Signed-off-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>

This option is true if a low-level driver can support sg
chaining. This will be removed eventually when all the drivers are
converted to support sg chaining. q->max_phys_segments is set to
SCSI_MAX_SG_SEGMENTS if false.
Signed-off-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

If you build a multiplatform kernel for iSeries and pSeries, with
ibmvscsic support, the resulting client doesn't work on iSeries.

This fixes that, using the appropriate low-level operations
for the machine detected at runtime.

[jejb: fixed up rejections around the srp transport patch]
Signed-off-by: NDavid Woodhouse <dwmw2@infradead.org>
Acked by: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: NPaul Mackerras <paulus@samba.org>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

This adds a 'roles' attribute to rport like transport_fc. The role can
be initiator or target. That is, the initiator driver creates target
remote ports and the target driver creates initiator remote ports.
Signed-off-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: NMike Christie <michaelc@cs.wisc.edu>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

This converts ibmvscsi to use the srp transport class.
Signed-off-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: NBrian King <brking@us.ibm.com>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

Signed-off-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: NBrian King <brking@linux.vnet.ibm.com>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

No need to check use_sg since sg_tablesize is set appropriately in the
scsi host template.

Brian King's patch (2a730937) did this
cleanup but the data buffer accessors patch (written before the patch
and merged after it) restored the check.
Signed-off-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: NBrian King <brking@linux.vnet.ibm.com>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

- remove the unnecessary map_single path.

- convert to use the new accessors for the sg lists and the
parameters.
Signed-off-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Santiago Leon <santil@us.ibm.com>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

The viosrp_crq timeout field is in seconds.
Signed-off-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Santiago Leon <santil@us.ibm.com>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

Since it is completely possible for scsi core to call
a LLDD's eh_abort function after the command has completed,
fix ibmvscsi to return SUCCESS if this is the case.
Signed-off-by: NBrian King <brking@linux.vnet.ibm.com>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

Fix a couple locking bugs discovered during code inspection.
ibmvscsi_send_srp_event needs to be called with the host lock
held. This patch fixes a couple paths in the code where this
wasn't true.
Signed-off-by: NBrian King <brking@linux.vnet.ibm.com>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

Adds an eh_host_reset_handler to ibmvscsi which resets the connection
to the vscsi server. This patch also adds a timer to internally
issues commands to prevent client hangs in the case of a misbehaving
server. Tested by modifying the VIOS such that it would occasionally
drop one or more request in sequence.
Signed-off-by: NBrian King <brking@linux.vnet.ibm.com>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

Converts ibmvscsi to use dev_printk and friends to simplify
debugging. ibmvscsi adapter initialization now looks like this:

ibmvscsi 30000005: SRP_VERSION: 16.a
ibmvscsi 30000005: partner initialization complete
ibmvscsi 30000005: sent SRP login
ibmvscsi 30000005: SRP_LOGIN succeeded

Additionally, this patch adds the logging of a couple return codes in
a couple logs.
Signed-off-by: NBrian King <brking@linux.vnet.ibm.com>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

Since sg_tablesize is set appropriately in the scsi host template,
remove the unnecessary check to make sure it is not exceeded
following the dma_map_sg call.
Signed-off-by: NBrian King <brking@linux.vnet.ibm.com>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

Adds support for a changeable queue depth to ibmvscsi.
Signed-off-by: NBrian King <brking@linux.vnet.ibm.com>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

Fixed the kernel-doc comment for ibmvscsi_slave_configure.  Thanks to
Randy Dunlap for pointing this out.

Adding a slave_configure function for the driver. Now the disks can be
restarted by the scsi mid-layer when the are disconnected and reconnected.
Signed-off-by: N"Robert Jennings" <rcj@linux.vnet.ibm.com>
Signed-off-by: N"Santiago Leon" <santil@us.ibm.com>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

The request limit calculations used previously on the client failed to
mirror the state of the server.  Additionally, when a value < 3 was provided
there could be problems setting can_queue and handling abort and reset
commands.
Signed-off-by: N"Robert Jennings" <rcj@linux.vnet.ibm.com>
Signed-off-by: NSantiago Leon <santil@us.ibm.com>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

The "ibmvscsi: treat busy and error conditions separately" patch
submitted by Dave Boutcher back in June incorrectly reenables the CRQ.
The broken logic causes the adapter to get disabled if the CRQ
connection happens to close temporarily.  This patch "fixes that
obviously wrong logic check" (Dave's words).
Signed-off-by: NSantiago Leon <santil@us.ibm.com>
Signed-off-by: NDavid Boutcher <sleddog@us.ibm.com>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

This patch fixes a condition where ibmvscsi treats a transport error as a
"busy" condition, so no errors were returned to the scsi mid-layer.
In a RAID environment this means that I/O hung rather than failing
over.
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

Signed-off-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

Convert kmalloc + memset to kcalloc in ibmvscsi
Signed-off-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: NDave Boutcher <sleddog@us.ibm.com>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

Signed-off-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

There is a window where we can be re-enabling an adapter, but
still allow SCSI commands to be sent to the target.  This fix
sets our window (request_limit) to -1 as soon as we know the
adapter is being reenabled, and closes a very teeny tiny
window where we could set the window back to 1 before we
grab a lock.
Signed-off-by: NDave Boutcher <sleddog@us.ibm.com>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

New versions of the Power5 firmware can send a "re-enable" message to
the virtual scsi adapter.  This fix makes us handle the message
correctly.  Without it, the driver goes catatonic and the system crashes
unpleasantly.
Signed-off-by: NDave Boutcher <sleddog@us.ibm.com>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>

Just set the name field directly in the device_driver structure
contained in the vio_driver struct.
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>

Linda Xie ever so gently pointed out that she had a patch
to preserve compatibility with older SLES targets, and I told
her we didn't need to push it to mainline.

This patch explicitly checks the version of the IBMVSCSI target
and ensures that large scatterlists are not sent to older
targets.
Signed-off-by: NLinda Xie <lxie@us.ibm.com>
Signed-off-by: NDave Boutcher <boutcher@us.ibm.com>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

The maximum size of a scatter-gather list that the current IBM VSCSI
Client can handle is 10.  This patch adds large scatter-gather support
to the client so that it is capable of handling up to SG_ALL(255)
number of requests in the scatter-gather list.
Signed-off-by: NLinda Xie <lxie@us.ibm.com>
Acked by: Dave C Boutcher <sleddog@us.ibm.com>

Rejections fixed up and
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

Make MODULE_DEVICE_TABLE work for vio devices.
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

This patch fixes a long term borkenness in
ibmvscsi where we were using the wrong timeout
field from the scsi command (and using the
wrong units.)  Now broken by the fact that the
scsi_cmnd timeout field is gone entirely.
This only worked before because all the SCSI
targets assumed that 0 was default.
Signed-off-by: NDave Boutcher <boutcher@us.ibm.com>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

With the removal of the spinlocking around eh calls, we need to add a
little more locking back in, otherwise we do some naked list
manipulation.
Signed-off-by: NDave Boutcher <boutcher@us.ibm.com>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

Fix the problem in IBM VSCSI Client where the client doesn't send the
information which is expected by the server.
Signed-off-by: NLinda Xie <lxie@us.ibm.com>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.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!