Re: [PATCH 3/3] Import fw-sbp2 driver.

Kristian Høgsberg
2006-12-14T20:50:50Z

Jeff Garzik wrote:

Again, thanks for your comments, I've added patches to my git repo, will send
out a new set on LKML before the end of this week.

>> +/* I don't know why the SCSI stack doesn't define something like
>> this... */
>> +typedef void (*scsi_done_fn_t) (struct scsi_cmnd *);
>
> submit a patch?

Hehe, yeah, that might work.

>> +struct sbp2_status {
>> + unsigned int orb_high:16;
>
> unsigned short? probably generates better code than a bitfield:16

This and all other bit fields are now just u32s that I access by shifting and
masking.

>> +struct sbp2_login_response {
>> + u16 login_id;
>> + u16 length;
>> + u32 command_block_agent_high;
>> + u32 command_block_agent_low;
>> + u32 reconnect_hold;
>> +};
>
> __le16 and __le32?

This struct is filled in using fw_memcpy_from_be32() to copy and byteswap the
incoming payload, so the fields here are always cpu endian. The two u16
fields assume little endian ordering though, I fixed that.

>> +sbp2_send_management_orb(struct fw_unit *unit, int node_id, int
>> generation,
>> + int function, int lun, void *response)
>> +{
>> + struct fw_device *device = fw_device(unit->device.parent);
>> + struct sbp2_device *sd = unit->device.driver_data;
>> + struct sbp2_management_orb *orb;
>> + unsigned long timeout;
>> + int retval = -EIO;
>> +
>> + orb = kzalloc(sizeof *orb, GFP_ATOMIC);
>> + if (orb == NULL)
>> + return -ENOMEM;
>> +
>> + /* The sbp2 device is going to send a block read request to
>> + * read out the request from host memory, so map it for
>> + * dma. */
>> + orb->base.request_bus =
>> + dma_map_single(device->card->device, &orb->request,
>> + sizeof orb->request, DMA_TO_DEVICE);
>> +
>> + orb->response_bus =
>> + dma_map_single(device->card->device, &orb->response,
>> + sizeof orb->response, DMA_FROM_DEVICE);
>
> check for DMA mapping error

Oops, fixed.

>> + if (sd->workarounds)
>> + fw_notify("Workarounds for node %s: 0x%x "
>> + "(firmware_revision 0x%06x, model_id 0x%06x)\n",
>> + unit->device.bus_id,
>> + sd->workarounds, firmware_revision, model);
>> +
>> + /* FIXME: Make this work for multi-lun devices. */
>> + lun = 0;
>
> doesn't allowing the stack to issue REPORT LUNS take care of this?

Possibly, I don't have firewire multi-LUN devices to test with here. The LUNs
are also discoverable from the firewire config rom, which is why I put the
comment there. This doesn't mean that the SCSI commands for discovering LUNs
doesn't also work.

>> +/* SCSI stack integration */
>> +
>> +static int sbp2_scsi_queuecommand(struct scsi_cmnd *cmd,
>> scsi_done_fn_t done)
>> +{
>> + if (cmd->cmnd[0] == REQUEST_SENSE) {
>> + fw_notify("request_sense");
>> + memcpy(cmd->request_buffer, cmd->sense_buffer,
>> cmd->request_bufflen);
>> + memset(cmd->sense_buffer, 0, sizeof(cmd->sense_buffer));
>> + cmd->result = DID_OK << 16;
>> + done(cmd);
>> + return 0;
>> + }
>
> this is a broken emulation. this command is specified to not repeatedly
> return the same sense data.

I copied it over from the old stack under the assumption that it fixed
something for some device. I took it out and tested with the 10 or so storage
devices I have here and it makes no difference. I've never seen the
fw_notify() that I put in there trigger. I'm taking out this workaround for
now, unless someone can tell me why it should stay there.

Kristian