linux-toradex.git/drivers/scsi/fnic, branch v3.10.42

lseek(fd, n, SEEK_END) does not go to eof - n

2013-06-16T18:10:53+00:00

When you copy some code, you are supposed to read it.  If nothing else,
there's a chance to spot and fix an obvious bug instead of sharing it...

X-Song: "I Got It From Agnes", by Tom Lehrer
Signed-off-by: Al Viro 
[ Tom Lehrer? You're dating yourself, Al ]
Signed-off-by: Linus Torvalds

[SCSI] fnic: Incremented driver version

2013-05-02T14:32:24+00:00

Signed-off-by: Brian Uchino 
Signed-off-by: Hiral Patel 
Signed-off-by: James Bottomley

[SCSI] fnic: Kernel panic due to FIP mode misconfiguration

2013-05-02T14:32:23+00:00

If switch configured in FIP and adapter configured in non-fip mode, driver
panics while queueing FIP frame in non-existing fip_frame_queue. Added config
check before queueing FIP frame in misconfiguration case to avoid kernel panic.

Signed-off-by: Hiral Patel 
Signed-off-by: James Bottomley

[SCSI] fnic: FIP VLAN Discovery Feature Support

2013-05-02T14:30:40+00:00

FIP VLAN discovery discovers the FCoE VLAN that will be used by all other FIP
protocols as well as by the FCoE encapsulation for Fibre Channel payloads on
the established virtual link. One of the goals of FC-BB-5 was to be as
nonintrusive as possible on initiators and targets, and therefore FIP VLAN
discovery occurs in the native VLAN used by the initiator or target to
exchange Ethernet traffic. The FIP VLAN discovery protocol is the only FIP
protocol running on the native VLAN; all other FIP protocols run on the
discovered FCoE VLANs.

If an administrator has manually configured FCoE VLANs on ENodes and FCFs,
there is no need to use this protocol. FIP and FCoE will run over the
configured VLANs.

An ENode without FCoE VLANs configuration would use this automated discovery
protocol to discover over which VLANs FCoE is running.

The ENode sends a FIP VLAN discovery request to a multicast MAC address called
All-FCF-MACs, which is a multicast MAC address to which all FCFs listen.

All FCFs that can be reached in the native VLAN of the ENode are expected to
respond on the same VLAN with a response that lists one or more FCoE VLANs
that are available for the ENode's VN_Port login. This protocol has the sole
purpose of allowing the ENode to discover all the available FCoE VLANs.

Now the ENode may enable a subset of these VLANs for FCoE Running the FIP
protocol in these VLANs on a per VLAN basis. And FCoE data transactions also
would occur on this VLAN. Hence, Except for FIP VLAN discovery, all other FIP
and FCoE traffic runs on the selected FCoE VLAN.  Its only the FIP VLAN
Discovery protocol that is permitted to run on the Default native VLAN of the
system.

[**** NOTE ****]
We are working on moving this feature definitions and functionality to libfcoe
module. We need this patch to be approved, as Suse is looking forward to merge
this feature in SLES 11 SP3 release.  Once this patch is approved, we will
submit patch which should move vlan discovery feature to libfoce.

[Fengguang Wu : kmalloc cast removal]
Signed-off-by: Anantha Prakash T 
Signed-off-by: Hiral Patel 
Signed-off-by: James Bottomley

[SCSI] fnic: Fnic Trace Utility

2013-02-22T17:32:07+00:00

Fnic Trace utility is a tracing functionality built directly into fnic driver
to trace events. The benefit that trace buffer brings to fnic driver is the
ability to see what it happening inside the fnic driver. It also provides the
capability to trace every IO event inside fnic driver to debug panics, hangs
and potentially IO corruption issues. This feature makes it easy to find
problems in fnic driver and it also helps in tracking down strange bugs in a
more manageable way. Trace buffer is shared across all fnic instances for
this implementation.

Signed-off-by: Hiral Patel 
Signed-off-by: James Bottomley

[SCSI] fnic: New debug flags and debug log messages

2013-02-22T17:31:09+00:00

Added new fnic debug flags for identifying IO state at every stage of IO while
debugging and also added more log messages for better debugging capability.

Signed-off-by: Sesidhar Baddela 
Signed-off-by: Hiral Patel 
Signed-off-by: James Bottomley

[SCSI] fnic: fnic driver may hit BUG_ON on device reset

2013-02-22T17:30:19+00:00

The issue was observed when LUN Reset is issued through IOCTL or sg_reset
utility.

fnic driver issues LUN RESET to firmware. On successful completion of device
reset, driver cleans up all the pending IOs that were issued prior to device
reset. These pending IOs are expected to be in ABTS_PENDING state. This works
fine, when the device reset operation resulted from midlayer, but not when
device reset was triggered from IOCTL path as the pending IOs were not in
ABTS_PENDING state. execution path hits panic if the pending IO is not in
ABTS_PENDING state.

Changes:
The fix replaces BUG_ON check in fnic_clean_pending_aborts() with marking
pending IOs as ABTS_PENDING if they were not in ABTS_PENDING state and skips
if they were already in ABTS_PENDING state. An extra check is added to validate
the abort status of the commands after a delay of 2 * E_D_TOV using a
helper function. The helper function returns 1 if it finds any pending IO in
ABTS_PENDING state, belong to the LUN on which device reset was issued else 0.
With this, device reset operation returns success only if the helper funciton
returns 0, otherwise it returns failure.

Other changes:
- Removed code in fnic_clean_pending_aborts() that returns failure if it finds
  io_req NULL, instead of returning failure added code to continue with next io
- Added device reset flags for debugging in fnic_terminate_rport_io,
  fnic_rport_exch_reset, and fnic_clean_pending_aborts

Signed-off-by: Narsimhulu Musini 
Signed-off-by: Hiral Patel 
Signed-off-by: James Bottomley

[SCSI] fnic: Fix SGEs limit

2013-02-22T17:29:35+00:00

Driver allows IOs with more SGEs than max SGEs supported by Palo. The current
max SGEs supported by the fnic driver is 1024. The current register settings
on Palo supports a max of 256 only. Palo would return any IO with more than
256 SGEs with an error indicating INVALID_SGLS. Fnic driver should limit the
max supported SGLs in the driver to 256 to avoid this error.

Signed-off-by: Sesidhar Baddela 
Signed-off-by: Hiral Patel 
Signed-off-by: James Bottomley

[SCSI] fnic: fixing issues in device and firmware reset code

2013-02-22T17:28:19+00:00

1. Handling overlapped firmware resets
     This fix serialize multiple firmware resets to avoid situation where fnic
     device fails to come up for link up event, when firmware resets are issued
     back to back. If there are overlapped firmware resets are issued,
     the firmware reset operation checks whether there is any firmware reset in
     progress, if so it polls for its completion in a loop with 100ms delay.

2. Handling device reset timeout
     fnic_device_reset code has been modified to handle Device reset timeout:
     - Issue terminate on device reset timeout.
     - Introduced flags field (one of the scratch fields in scsi_cmnd).
     With this, device reset request would have DEVICE_RESET flag set for other
     routines to determine the type of the request.
     Also modified fnic_terminate_rport_io, fnic_rport_exch_rset, completion
     routines to handle SCSI commands with DEVICE_RESET flag.

3. LUN/Device Reset hangs when issued through IOCTL using utilities like
   sg_reset.
     Each SCSI command is associated with a valid tag, fnic uses this tag to
     retrieve associated scsi command on completion. the LUN/Device Reset issued
     through IOCTL resulting into a SCSI command that is not associated with a
     valid tag. So fnic fails to retrieve associated scsi command on completion,
     which causes hang. This fix allocates tag, associates it with the
     scsi command and frees the tag, when the operation completed.

4. Preventing IOs during firmware reset.
     Current fnic implementation allows IO submissions during firmware reset.
     This fix synchronizes IO submissions and firmware reset operations.
     It ensures that IOs issued to fnic prior to reset will be issued to the
     firmware before firmware reset.

Signed-off-by: Narsimhulu Musini 
Signed-off-by: Hiral Patel 
Signed-off-by: James Bottomley

[SCSI] fnic: fix for trusted cos

2013-01-29T03:00:04+00:00

Modified fnic driver to let hardware insert the COS value. Set bit
in descriptor to 0 telling hardware to use its lif COS configurations
to insert the COS value in the frames.

Signed-off-by: Narsimhulu Musini 
Signed-off-by: Hiral Patel 
Signed-off-by: James Bottomley