linux/drivers/scsi/libsas/sas_host_smp.c
Tejun Heo c3a4d78c58 block: add rq->resid_len
rq->data_len served two purposes - the length of data buffer on issue
and the residual count on completion.  This duality creates some
headaches.

First of all, block layer and low level drivers can't really determine
what rq->data_len contains while a request is executing.  It could be
the total request length or it coulde be anything else one of the
lower layers is using to keep track of residual count.  This
complicates things because blk_rq_bytes() and thus
[__]blk_end_request_all() relies on rq->data_len for PC commands.
Drivers which want to report residual count should first cache the
total request length, update rq->data_len and then complete the
request with the cached data length.

Secondly, it makes requests default to reporting full residual count,
ie. reporting that no data transfer occurred.  The residual count is
an exception not the norm; however, the driver should clear
rq->data_len to zero to signify the normal cases while leaving it
alone means no data transfer occurred at all.  This reverse default
behavior complicates code unnecessarily and renders block PC on some
drivers (ide-tape/floppy) unuseable.

This patch adds rq->resid_len which is used only for residual count.

While at it, remove now unnecessasry blk_rq_bytes() caching in
ide_pc_intr() as rq->data_len is not changed anymore.

Boaz	: spotted missing conversion in osd
Sergei	: spotted too early conversion to blk_rq_bytes() in ide-tape

[ Impact: cleanup residual count handling, report 0 resid by default ]

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Cc: Borislav Petkov <petkovbb@googlemail.com>
Cc: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Cc: Mike Miller <mike.miller@hp.com>
Cc: Eric Moore <Eric.Moore@lsi.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Doug Gilbert <dgilbert@interlog.com>
Cc: Mike Miller <mike.miller@hp.com>
Cc: Eric Moore <Eric.Moore@lsi.com>
Cc: Darrick J. Wong <djwong@us.ibm.com>
Cc: Pete Zaitcev <zaitcev@redhat.com>
Cc: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-05-11 09:50:53 +02:00

277 lines
6.9 KiB
C

/*
* Serial Attached SCSI (SAS) Expander discovery and configuration
*
* Copyright (C) 2007 James E.J. Bottomley
* <James.Bottomley@HansenPartnership.com>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; version 2 only.
*/
#include <linux/scatterlist.h>
#include <linux/blkdev.h>
#include "sas_internal.h"
#include <scsi/scsi_transport.h>
#include <scsi/scsi_transport_sas.h>
#include "../scsi_sas_internal.h"
static void sas_host_smp_discover(struct sas_ha_struct *sas_ha, u8 *resp_data,
u8 phy_id)
{
struct sas_phy *phy;
struct sas_rphy *rphy;
if (phy_id >= sas_ha->num_phys) {
resp_data[2] = SMP_RESP_NO_PHY;
return;
}
resp_data[2] = SMP_RESP_FUNC_ACC;
phy = sas_ha->sas_phy[phy_id]->phy;
resp_data[9] = phy_id;
resp_data[13] = phy->negotiated_linkrate;
memcpy(resp_data + 16, sas_ha->sas_addr, SAS_ADDR_SIZE);
memcpy(resp_data + 24, sas_ha->sas_phy[phy_id]->attached_sas_addr,
SAS_ADDR_SIZE);
resp_data[40] = (phy->minimum_linkrate << 4) |
phy->minimum_linkrate_hw;
resp_data[41] = (phy->maximum_linkrate << 4) |
phy->maximum_linkrate_hw;
if (!sas_ha->sas_phy[phy_id]->port ||
!sas_ha->sas_phy[phy_id]->port->port_dev)
return;
rphy = sas_ha->sas_phy[phy_id]->port->port_dev->rphy;
resp_data[12] = rphy->identify.device_type << 4;
resp_data[14] = rphy->identify.initiator_port_protocols;
resp_data[15] = rphy->identify.target_port_protocols;
}
static void sas_report_phy_sata(struct sas_ha_struct *sas_ha, u8 *resp_data,
u8 phy_id)
{
struct sas_rphy *rphy;
struct dev_to_host_fis *fis;
int i;
if (phy_id >= sas_ha->num_phys) {
resp_data[2] = SMP_RESP_NO_PHY;
return;
}
resp_data[2] = SMP_RESP_PHY_NO_SATA;
if (!sas_ha->sas_phy[phy_id]->port)
return;
rphy = sas_ha->sas_phy[phy_id]->port->port_dev->rphy;
fis = (struct dev_to_host_fis *)
sas_ha->sas_phy[phy_id]->port->port_dev->frame_rcvd;
if (rphy->identify.target_port_protocols != SAS_PROTOCOL_SATA)
return;
resp_data[2] = SMP_RESP_FUNC_ACC;
resp_data[9] = phy_id;
memcpy(resp_data + 16, sas_ha->sas_phy[phy_id]->attached_sas_addr,
SAS_ADDR_SIZE);
/* check to see if we have a valid d2h fis */
if (fis->fis_type != 0x34)
return;
/* the d2h fis is required by the standard to be in LE format */
for (i = 0; i < 20; i += 4) {
u8 *dst = resp_data + 24 + i, *src =
&sas_ha->sas_phy[phy_id]->port->port_dev->frame_rcvd[i];
dst[0] = src[3];
dst[1] = src[2];
dst[2] = src[1];
dst[3] = src[0];
}
}
static void sas_phy_control(struct sas_ha_struct *sas_ha, u8 phy_id,
u8 phy_op, enum sas_linkrate min,
enum sas_linkrate max, u8 *resp_data)
{
struct sas_internal *i =
to_sas_internal(sas_ha->core.shost->transportt);
struct sas_phy_linkrates rates;
if (phy_id >= sas_ha->num_phys) {
resp_data[2] = SMP_RESP_NO_PHY;
return;
}
switch (phy_op) {
case PHY_FUNC_NOP:
case PHY_FUNC_LINK_RESET:
case PHY_FUNC_HARD_RESET:
case PHY_FUNC_DISABLE:
case PHY_FUNC_CLEAR_ERROR_LOG:
case PHY_FUNC_CLEAR_AFFIL:
case PHY_FUNC_TX_SATA_PS_SIGNAL:
break;
default:
resp_data[2] = SMP_RESP_PHY_UNK_OP;
return;
}
rates.minimum_linkrate = min;
rates.maximum_linkrate = max;
if (i->dft->lldd_control_phy(sas_ha->sas_phy[phy_id], phy_op, &rates))
resp_data[2] = SMP_RESP_FUNC_FAILED;
else
resp_data[2] = SMP_RESP_FUNC_ACC;
}
int sas_smp_host_handler(struct Scsi_Host *shost, struct request *req,
struct request *rsp)
{
u8 *req_data = NULL, *resp_data = NULL, *buf;
struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
int error = -EINVAL;
/* eight is the minimum size for request and response frames */
if (req->data_len < 8 || rsp->data_len < 8)
goto out;
if (bio_offset(req->bio) + req->data_len > PAGE_SIZE ||
bio_offset(rsp->bio) + rsp->data_len > PAGE_SIZE) {
shost_printk(KERN_ERR, shost,
"SMP request/response frame crosses page boundary");
goto out;
}
req_data = kzalloc(req->data_len, GFP_KERNEL);
/* make sure frame can always be built ... we copy
* back only the requested length */
resp_data = kzalloc(max(rsp->data_len, 128U), GFP_KERNEL);
if (!req_data || !resp_data) {
error = -ENOMEM;
goto out;
}
local_irq_disable();
buf = kmap_atomic(bio_page(req->bio), KM_USER0) + bio_offset(req->bio);
memcpy(req_data, buf, req->data_len);
kunmap_atomic(buf - bio_offset(req->bio), KM_USER0);
local_irq_enable();
if (req_data[0] != SMP_REQUEST)
goto out;
/* always succeeds ... even if we can't process the request
* the result is in the response frame */
error = 0;
/* set up default don't know response */
resp_data[0] = SMP_RESPONSE;
resp_data[1] = req_data[1];
resp_data[2] = SMP_RESP_FUNC_UNK;
req->resid_len = req->data_len;
rsp->resid_len = rsp->data_len;
switch (req_data[1]) {
case SMP_REPORT_GENERAL:
req->resid_len -= 8;
rsp->resid_len -= 32;
resp_data[2] = SMP_RESP_FUNC_ACC;
resp_data[9] = sas_ha->num_phys;
break;
case SMP_REPORT_MANUF_INFO:
req->resid_len -= 8;
rsp->resid_len -= 64;
resp_data[2] = SMP_RESP_FUNC_ACC;
memcpy(resp_data + 12, shost->hostt->name,
SAS_EXPANDER_VENDOR_ID_LEN);
memcpy(resp_data + 20, "libsas virt phy",
SAS_EXPANDER_PRODUCT_ID_LEN);
break;
case SMP_READ_GPIO_REG:
/* FIXME: need GPIO support in the transport class */
break;
case SMP_DISCOVER:
req->resid_len -= 16;
if ((int)req->resid_len < 0) {
req->resid_len = 0;
error = -EINVAL;
goto out;
}
rsp->resid_len -= 56;
sas_host_smp_discover(sas_ha, resp_data, req_data[9]);
break;
case SMP_REPORT_PHY_ERR_LOG:
/* FIXME: could implement this with additional
* libsas callbacks providing the HW supports it */
break;
case SMP_REPORT_PHY_SATA:
req->resid_len -= 16;
if ((int)req->resid_len < 0) {
req->resid_len = 0;
error = -EINVAL;
goto out;
}
rsp->resid_len -= 60;
sas_report_phy_sata(sas_ha, resp_data, req_data[9]);
break;
case SMP_REPORT_ROUTE_INFO:
/* Can't implement; hosts have no routes */
break;
case SMP_WRITE_GPIO_REG:
/* FIXME: need GPIO support in the transport class */
break;
case SMP_CONF_ROUTE_INFO:
/* Can't implement; hosts have no routes */
break;
case SMP_PHY_CONTROL:
req->resid_len -= 44;
if ((int)req->resid_len < 0) {
req->resid_len = 0;
error = -EINVAL;
goto out;
}
rsp->resid_len -= 8;
sas_phy_control(sas_ha, req_data[9], req_data[10],
req_data[32] >> 4, req_data[33] >> 4,
resp_data);
break;
case SMP_PHY_TEST_FUNCTION:
/* FIXME: should this be implemented? */
break;
default:
/* probably a 2.0 function */
break;
}
local_irq_disable();
buf = kmap_atomic(bio_page(rsp->bio), KM_USER0) + bio_offset(rsp->bio);
memcpy(buf, resp_data, rsp->data_len);
flush_kernel_dcache_page(bio_page(rsp->bio));
kunmap_atomic(buf - bio_offset(rsp->bio), KM_USER0);
local_irq_enable();
out:
kfree(req_data);
kfree(resp_data);
return error;
}