[SCSI] transport_sas: add SAS management protocol support
The sas transport class attaches one bsg device to every SAS object
(host, device, expander, etc). LLDs can define a function to handle
SMP requests via sas_function_template::smp_handler.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
diff --git a/drivers/scsi/Kconfig b/drivers/scsi/Kconfig
index 07a6911..bebe43e 100644
--- a/drivers/scsi/Kconfig
+++ b/drivers/scsi/Kconfig
@@ -282,7 +282,7 @@
config SCSI_SAS_ATTRS
tristate "SAS Transport Attributes"
- depends on SCSI
+ depends on SCSI && BLK_DEV_BSG
help
If you wish to export transport-specific information about
each attached SAS device to sysfs, say Y.
diff --git a/drivers/scsi/scsi_transport_sas.c b/drivers/scsi/scsi_transport_sas.c
index b2ef71a..2871fd0 100644
--- a/drivers/scsi/scsi_transport_sas.c
+++ b/drivers/scsi/scsi_transport_sas.c
@@ -29,6 +29,8 @@
#include <linux/err.h>
#include <linux/slab.h>
#include <linux/string.h>
+#include <linux/blkdev.h>
+#include <linux/bsg.h>
#include <scsi/scsi.h>
#include <scsi/scsi_device.h>
@@ -152,6 +154,76 @@
sas_bitfield_name_search(linkspeed, sas_linkspeed_names)
sas_bitfield_name_set(linkspeed, sas_linkspeed_names)
+static void sas_smp_request(struct request_queue *q, struct Scsi_Host *shost,
+ struct sas_rphy *rphy)
+{
+ struct request *req;
+ int ret;
+ int (*handler)(struct Scsi_Host *, struct sas_rphy *, struct request *);
+
+ while (!blk_queue_plugged(q)) {
+ req = elv_next_request(q);
+ if (!req)
+ break;
+
+ blkdev_dequeue_request(req);
+
+ spin_unlock_irq(q->queue_lock);
+
+ handler = to_sas_internal(shost->transportt)->f->smp_handler;
+ ret = handler(shost, rphy, req);
+
+ spin_lock_irq(q->queue_lock);
+
+ req->end_io(req, ret);
+ }
+}
+
+static void sas_host_smp_request(struct request_queue *q)
+{
+ sas_smp_request(q, (struct Scsi_Host *)q->queuedata, NULL);
+}
+
+static void sas_non_host_smp_request(struct request_queue *q)
+{
+ struct sas_rphy *rphy = q->queuedata;
+ sas_smp_request(q, rphy_to_shost(rphy), rphy);
+}
+
+static int sas_bsg_initialize(struct Scsi_Host *shost, struct sas_rphy *rphy,
+ char *name)
+{
+ struct request_queue *q;
+ int error;
+
+ if (!to_sas_internal(shost->transportt)->f->smp_handler) {
+ printk("%s can't handle SMP requests\n", shost->hostt->name);
+ return 0;
+ }
+
+ if (rphy)
+ q = blk_init_queue(sas_non_host_smp_request, NULL);
+ else
+ q = blk_init_queue(sas_host_smp_request, NULL);
+ if (!q)
+ return -ENOMEM;
+
+ error = bsg_register_queue(q, name);
+ if (error) {
+ blk_cleanup_queue(q);
+ return -ENOMEM;
+ }
+
+ if (rphy)
+ q->queuedata = rphy;
+ else
+ q->queuedata = shost;
+
+ set_bit(QUEUE_FLAG_BIDI, &q->queue_flags);
+
+ return 0;
+}
+
/*
* SAS host attributes
*/
@@ -161,12 +233,19 @@
{
struct Scsi_Host *shost = dev_to_shost(dev);
struct sas_host_attrs *sas_host = to_sas_host_attrs(shost);
+ char name[BUS_ID_SIZE];
INIT_LIST_HEAD(&sas_host->rphy_list);
mutex_init(&sas_host->lock);
sas_host->next_target_id = 0;
sas_host->next_expander_id = 0;
sas_host->next_port_id = 0;
+
+ snprintf(name, sizeof(name), "sas_host%d", shost->host_no);
+ if (sas_bsg_initialize(shost, NULL, name))
+ dev_printk(KERN_ERR, dev, "fail to a bsg device %d\n",
+ shost->host_no);
+
return 0;
}
@@ -1221,6 +1300,9 @@
sas_rphy_initialize(&rdev->rphy);
transport_setup_device(&rdev->rphy.dev);
+ if (sas_bsg_initialize(shost, &rdev->rphy, rdev->rphy.dev.bus_id))
+ printk("fail to a bsg device %s\n", rdev->rphy.dev.bus_id);
+
return &rdev->rphy;
}
EXPORT_SYMBOL(sas_end_device_alloc);
@@ -1260,6 +1342,9 @@
sas_rphy_initialize(&rdev->rphy);
transport_setup_device(&rdev->rphy.dev);
+ if (sas_bsg_initialize(shost, &rdev->rphy, rdev->rphy.dev.bus_id))
+ printk("fail to a bsg device %s\n", rdev->rphy.dev.bus_id);
+
return &rdev->rphy;
}
EXPORT_SYMBOL(sas_expander_alloc);