This is a patch for the FC transport in an effort to support pass
through services based on previous discussion as below,
http://marc.info/?t=121569558300005&r=1&w=2
Following are remarks for the changes,
- the SMP in the SAS transport has referenced, so the layout of the
changes are quite similar to it
- at this stage, the ELS/CT service packet serviced one at a time,
synchronously
- there is dedicated handler in the LLDD for ELS and CT, respectively
- the sense data area of the 'request' structure will hold service reply
- device files are created in following directories for each of
discovered initiator/targets,
= /sys/class/bsg/rport-<host_no>:<bus>-<id>
= /dev/rport-<host_no>:<bus>-<id>
And following are to-dos,
- abort mechanism
- asynchronous packet handling
- detailing error handling, etc.
The patch has created against scsi-misc.
With this patch, qla2xxx is under testing for the feature.
Thank you,
Seokmann
---
diff --git a/drivers/scsi/scsi_transport_fc.c b/drivers/scsi/
scsi_transport_fc.c
index 56823fd..44f6a9e 100644
--- a/drivers/scsi/scsi_transport_fc.c
+++ b/drivers/scsi/scsi_transport_fc.c
@@ -40,6 +40,7 @@
static int fc_queue_work(struct Scsi_Host *, struct work_struct *);
static void fc_vport_sched_delete(struct work_struct *work);
+static void fc_bsg_remove(struct Scsi_Host *, struct fc_rport *);
/*
* This is a temporary carrier for creating a vport. It will
eventually
@@ -67,6 +68,12 @@ struct fc_vport_identifiers {
static int fc_vport_create(struct Scsi_Host *shost, int channel,
struct device *pdev, struct fc_vport_identifiers *ids,
struct fc_vport **vport);
+static void fc_service_timedout(unsigned long);
+static void fc_service_done(struct fc_service *);
+static int
+fc_service_handler(struct Scsi_Host *, struct fc_rport *, struct
request *);
+
+struct kmem_cache *fc_service_cache;
/*
* Redefine so that we can have same named attributes in the
@@ -666,6 +673,11 @@ static __init int fc_transport_init(void)
error = transport_class_register(&fc_rport_class);
if (error)
return error;
+ fc_service_cache = kmem_cache_create("fc_service",
+ sizeof(struct fc_service),
+ 0, SLAB_HWCACHE_ALIGN, NULL);
+ if (!fc_service_cache)
+ return -ENOMEM;
return transport_class_register(&fc_transport_class);
}
@@ -675,6 +687,7 @@ static void __exit fc_transport_exit(void)
transport_class_unregister(&fc_rport_class);
transport_class_unregister(&fc_host_class);
transport_class_unregister(&fc_vport_class);
+ kmem_cache_destroy(fc_service_cache);
}
/*
@@ -2081,6 +2094,9 @@ fc_attach_transport(struct fc_function_template
*ft)
i->f = ft;
+ /* for FC services (FC-CT, ELS, etc.) */
+ i->f->fc_service_handler = fc_service_handler;
+
/* Transport uses the shost workq for scsi scanning */
i->t.create_work_queue = 1;
@@ -2430,12 +2446,234 @@ fc_rport_final_delete(struct work_struct *work)
transport_remove_device(dev);
device_del(dev);
+ fc_bsg_remove(shost, rport);
transport_destroy_device(dev);
put_device(&shost->shost_gendev); /* for fc_host->rport list */
put_device(dev); /* for self-reference */
}
+static void fc_service_timedout(unsigned long _service)
+{
+ struct fc_service *service = (void *) _service;
+ unsigned long flags;
+
+ spin_lock_irqsave(&service->service_state_lock, flags);
+ if (!(service->service_state_flags & FC_SERVICE_STATE_DONE))
+ service->service_state_flags |= FC_SERVICE_STATE_ABORTED;
+ spin_unlock_irqrestore(&service->service_state_lock, flags);
+
+ complete(&service->completion);
+}
+
+static void fc_service_done(struct fc_service *service)
+{
+ if (!del_timer(&service->timer))
+ return;
+ complete (&service->completion);
+}
+
+static int
+issue_fc_service(struct fc_rport *rport, void *req, int req_size,
+ void *resp, int resp_size, void *service_reply)
+{
+ int res, retry;
+ struct fc_service *service = NULL;
+ struct Scsi_Host *shost = rport_to_shost(rport);
+ struct fc_internal *i = to_fc_internal(shost->transportt);
+ struct fc_frame_header *frame = req;
+
+ if ((frame->fh_type == FC_FRAME_TYPE_ELS) ||
+ (frame->fh_type == FC_FRAME_TYPE_FC_CT))
+ service->service_type = frame->fh_type;
+ else {
+ printk(KERN_ERR "invalid FC service type = %2x\n",
+ frame->fh_type);
+ return -EINVAL;
+ }
+
+ service = fc_alloc_service(GFP_KERNEL);
+ if (!service)
+ return -ENOMEM;
+
+ service->ct_frame = (struct fc_ct_frame *) req;
+ service->req_size = req_size;
+ service->response = resp;
+ service->resp_size = resp_size;
+ service->rport = rport;
+ /* sense area of the request structure */
+ service->reply = service_reply;
+ service->service_done = fc_service_done;
+
+ service->timer.data = (unsigned long) service;
+ service->timer.function = fc_service_timedout;
+ service->timer.expires = jiffies + FC_SERVICE_TIMEOUT*HZ;
+
+ add_timer(&service->timer);
+
+ if (service->service_type == FC_FRAME_TYPE_ELS)
+ res = i->f->execute_fc_els_service(service);
+ else if (service->service_type == FC_FRAME_TYPE_FC_CT)
+ res = i->f->execute_fc_ct_service(service);
+ else
+ printk(KERN_WARNING "%s: ERROR: invalid "
+ "FC service type = %2x\n", __func__,
+ service->service_type);
+
+ if (res) {
+ del_timer(&service->timer);
+ printk(KERN_ERR "executing FC service failed:%d\n", res);
+ goto ex_err;
+ }
+
+ wait_for_completion(&service->completion);
+
+ res = -ECOMM;
+ if ((service->service_state_flags & FC_SERVICE_STATE_ABORTED)) {
+ printk(KERN_ERR "FC service timed out or aborted\n");
+ i->f->abort_fc_service(service);
+ if (!(service->service_state_flags &
+ FC_SERVICE_STATE_DONE)) {
+ printk(KERN_ERR "FC service aborted and not done\n");
+ goto ex_err;
+ }
+ }
+ if (service->service_status.resp == FC_SERVICE_COMPLETE)
+ res = 0;
+ else {
+ printk(KERN_ERR "%s: FC service to rport %p"
+ " response: 0x%x", __func__, rport,
+ service->service_status.resp);
+ fc_free_service(service);
+ service = NULL;
+ }
+ex_err:
+ BUG_ON(retry == 3 && service != NULL);
+ if (service != NULL) {
+ fc_free_service(service);
+ }
+ return res;
+}
+
+static int
+fc_service_handler(struct Scsi_Host *shost, struct fc_rport *rport,
+ struct request *req)
+{
+ int ret;
+ struct request *rsp = req->next_rq;
+
+ if (!rsp) {
+ printk("%s: space for a FC service response is missing\n",
+ __func__);
+ return -EINVAL;
+ }
+
+ /* do we need to support multiple segments? */
+ if (req->bio->bi_vcnt > 1 || rsp->bio->bi_vcnt > 1) {
+ printk("%s: multiple segments req %u %u, rsp %u %u\n",
+ __func__, req->bio->bi_vcnt, req->data_len,
+ rsp->bio->bi_vcnt, rsp->data_len);
+ return -EINVAL;
+ }
+
+ ret = issue_fc_service(rport, bio_data(req->bio), req->data_len,
+ bio_data(rsp->bio), rsp->data_len, req->sense);
+ if (ret > 0) {
+ /* positive number is the untransferred residual */
+ rsp->data_len = ret;
+ req->data_len = 0;
+ ret = 0;
+ } else if (ret == 0) {
+ rsp->data_len = 0;
+ req->data_len = 0;
+ }
+
+ return ret;
+}
+
+static void fc_service_request(struct request_queue *q)
+{
+ struct request *req;
+ struct fc_rport *rport = q->queuedata;
+ struct Scsi_Host *shost = rport_to_shost(rport);
+ int (*handler)(struct Scsi_Host *, struct fc_rport *,
+ 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_fc_internal(shost->transportt)->f->fc_service_handler;
+ if (handler)
+ req->errors = handler(shost, rport, req);
+
+ spin_lock_irq(q->queue_lock);
+
+ req->end_io(req, req->errors);
+ }
+}
+
+static int
+fc_bsg_initialize(struct Scsi_Host *shost, struct fc_rport *rport)
+{
+ struct request_queue *q;
+ int error;
+ struct device *dev;
+ const char *name;
+ void (*release)(struct device *);
+
+ if (!to_fc_internal(shost->transportt)->f->fc_service_handler) {
+ printk("%s can't handle FC service requests\n", shost->hostt->name);
+ return 0;
+ }
+
+ if (!rport) {
+ printk(KERN_WARNING " ERROR: rport is NULL\n");
+ return -ENOMEM;
+ }
+
+ q = blk_init_queue(fc_service_request, NULL);
+ dev = &rport->dev;
+ name = dev->bus_id;
+ release = NULL;
+
+ if (!q)
+ return -ENOMEM;
+
+ error = bsg_register_queue(q, dev, name, release);
+ if (error) {
+ blk_cleanup_queue(q);
+ return -ENOMEM;
+ }
+
+ rport->q = q;
+
+ q->queuedata = rport;
+
+ queue_flag_set_unlocked(QUEUE_FLAG_BIDI, q);
+
+ return 0;
+}
+
+static void
+fc_bsg_remove(struct Scsi_Host *shost, struct fc_rport *rport)
+{
+ struct request_queue *q = rport->q;
+
+ if (!q) {
+ printk(KERN_WARNING "%s: ERROR: invalid queue\n",
+ __func__);
+ return;
+ }
+
+ bsg_unregister_queue(q);
+}
+
/**
* fc_rport_create - allocates and creates a remote FC port.
* @shost: scsi host the remote port is connected to.
@@ -2495,6 +2733,7 @@ fc_rport_create(struct Scsi_Host *shost, int
channel,
else
rport->scsi_target_id = -1;
list_add_tail(&rport->peers, &fc_host->rports);
+
get_device(&shost->shost_gendev); /* for fc_host->rport list */
spin_unlock_irqrestore(shost->host_lock, flags);
@@ -2515,6 +2754,9 @@ fc_rport_create(struct Scsi_Host *shost, int
channel,
transport_add_device(dev);
transport_configure_device(dev);
+ if (fc_bsg_initialize(shost, rport))
+ printk("fail to a bsg device %s\n", rport->dev.bus_id);
+
if (rport->roles & FC_PORT_ROLE_FCP_TARGET) {
/* initiate a scan of the target */
rport->flags |= FC_RPORT_SCAN_PENDING;
diff --git a/include/scsi/scsi_transport_fc.h b/include/scsi/
scsi_transport_fc.h
index 878373c..f54e067 100644
--- a/include/scsi/scsi_transport_fc.h
+++ b/include/scsi/scsi_transport_fc.h
@@ -32,7 +32,7 @@
#include <scsi/scsi_netlink.h>
struct scsi_transport_template;
-
+extern struct kmem_cache *fc_service_cache;
/*
* FC Port definitions - Following FC HBAAPI guidelines
@@ -333,6 +333,8 @@ struct fc_rport { /* aka fc_starget_attrs */
struct delayed_work fail_io_work;
struct work_struct stgt_delete_work;
struct work_struct rport_delete_work;
+
+ struct request_queue *q;
} __attribute__((aligned(sizeof(unsigned long))));
/* bit field values for struct fc_rport "flags" field: */
@@ -495,6 +497,129 @@ struct fc_host_attrs {
struct workqueue_struct *devloss_work_q;
};
+#define FC_STATUS_BUF_SIZE 96
+
+enum fc_frame_type {
+ FC_FRAME_TYPE_BS,
+ FC_FRAME_TYPE_ELS,
+ FC_FRAME_TYPE_IEC = 4,
+ FC_FRAME_TYPE_IP,
+ FC_FRAME_TYPE_FCP = 8,
+ FC_FRAME_TYPE_GPP,
+ FC_FRAME_TYPE_FC_CT = 0x20,
+};
+
+enum service_response {
+ FC_SERVICE_COMPLETE,
+ FC_SERVICE_UNDELIVERED = -1,
+};
+
+#define FC_SERVICE_STATE_PENDING 1
+#define FC_SERVICE_STATE_DONE 2
+#define FC_SERVICE_STATE_ABORTED 4
+#define FC_SERVICE_AT_INITIATOR 16
+
+struct fc_service_status {
+ enum service_response resp;
+ int buf_valid_size;
+
+ u8 buf[FC_STATUS_BUF_SIZE];
+
+ u32 residual;
+};
+
+/* NOTE - fc_frame_header is already defined in open-fcoe-upstream
branch */
+/*
+ * Frame header
+ */
+struct fc_frame_header {
+ __u8 fh_r_ctl; /* routing control */
+ __u8 fh_d_id[3]; /* Destination ID */
+
+ __u8 fh_cs_ctl; /* class of service control / pri */
+ __u8 fh_s_id[3]; /* Source ID */
+
+ __u8 fh_type; /* see enum fc_fh_type below */
+ __u8 fh_f_ctl[3]; /* frame control */
+
+ __u8 fh_seq_id; /* sequence ID */
+ __u8 fh_df_ctl; /* data field control */
+ __be16 fh_seq_cnt; /* sequence count */
+
+ __be16 fh_ox_id; /* originator exchange ID */
+ __be16 fh_rx_id; /* responder exchange ID */
+ __be32 fh_parm_offset; /* parameter or relative offset */
+};
+
+/* TBD - fc_els_hdr to move to ~/include/scsi/fc/fc_els.h */
+struct fc_els_hdr {
+ __u8 els_cmd;
+ __u8 els_param[3];
+};
+
+/* NOTE - fc_ct_hdr is already defined in open-fcoe-upstream branch */
+/*
+ * Fibre Channel Services - Common Transport.
+ * From T11.org FC-GS-2 Rev 5.3 November 1998.
+ */
+
+struct fc_ct_hdr {
+ __u8 ct_rev; /* revision */
+ __u8 ct_in_id[3]; /* N_Port ID of original requestor */
+ __u8 ct_fs_type; /* type of fibre channel service */
+ __u8 ct_fs_subtype; /* subtype */
+ __u8 ct_options;
+ __u8 _ct_resvd1;
+ __be16 ct_cmd; /* command / response code */
+ __be16 ct_mr_size; /* maximum / residual size */
+ __u8 _ct_resvd2;
+ __u8 ct_reason; /* reject reason */
+ __u8 ct_explan; /* reason code explanation */
+ __u8 ct_vendor; /* vendor unique data */
+};
+
+struct fc_ct_frame {
+ struct fc_frame_header fc_hdr;
+ struct fc_ct_hdr ct_hdr;
+ u32 ct_cmd[1];
+};
+
+struct fc_els_frame {
+ struct fc_frame_header fc_hdr;
+ struct fc_els_hdr els_hdr;
+ u32 els_cmd[4];
+};
+
+#define FC_SERVICE_TIMEOUT 10
+
+struct fc_service {
+ struct fc_rport *rport;
+ struct list_head list;
+
+ spinlock_t service_state_lock;
+ unsigned service_state_flags;
+
+ enum fc_frame_type service_type;
+
+ /* Used by the discovery code. */
+ struct timer_list timer;
+ struct completion completion;
+
+ union {
+ struct fc_ct_frame *ct_frame;
+ struct fc_els_frame *els_frame;
+ };
+ int req_size;
+ void *response;
+ int resp_size;
+
+ struct fc_service_status service_status;
+ void *reply; /* pointer to sense area of request */
+ void (*service_done)(struct fc_service *);
+
+ struct work_struct abort_work;
+};
+
#define shost_to_fc_host(x) \
((struct fc_host_attrs *)(x)->shost_data)
@@ -593,6 +718,14 @@ struct fc_function_template {
int (* tsk_mgmt_response)(struct Scsi_Host *, u64, u64, int);
int (* it_nexus_response)(struct Scsi_Host *, u64, int);
+ /* fibre-channel services */
+ int (*fc_service_handler)(struct Scsi_Host *,
+ struct fc_rport *rport,
+ struct request *);
+ int (*execute_fc_els_service)(struct fc_service *);
+ int (*execute_fc_ct_service)(struct fc_service *);
+ int (*abort_fc_service)(struct fc_service *);
+
/* allocation lengths for host-specific data */
u32 dd_fcrport_size;
u32 dd_fcvport_size;
@@ -713,6 +846,31 @@ fc_vport_set_state(struct fc_vport *vport, enum
fc_vport_state new_state)
vport->vport_state = new_state;
}
+static inline struct fc_service *
+fc_alloc_service(gfp_t flags)
+{
+ struct fc_service *service = kmem_cache_zalloc(fc_service_cache,
flags);
+
+ if (service) {
+ INIT_LIST_HEAD(&service->list);
+ spin_lock_init(&service->service_state_lock);
+ service->service_state_flags = FC_SERVICE_STATE_PENDING;
+ init_timer(&service->timer);
+ init_completion(&service->completion);
+ }
+
+ return service;
+}
+
+static inline void
+fc_free_service(struct fc_service *service)
+{
+ if (service) {
+ BUG_ON(!list_empty(&service->list));
+ kmem_cache_free(fc_service_cache, service);
+ }
+}
+
struct scsi_transport_template *fc_attach_transport(
struct fc_function_template *);
---
--
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