From 9e4f5e29610162fd426366f3b29e3cc6e575b858 Mon Sep 17 00:00:00 2001 From: James Smart Date: Thu, 26 Mar 2009 13:33:19 -0400 Subject: [SCSI] FC Pass Thru support Attached is the ELS/CT pass-thru patch for the FC Transport. The patch creates a generic framework that lays on top of bsg and the SGIO v4 ioctl in order to pass transaction requests to LLDD's. The interface supports the following operations: On an fc_host basis: Request login to the specified N_Port_ID, creating an fc_rport. Request logout of the specified N_Port_ID, deleting an fc_rport Send ELS request to specified N_Port_ID w/o requiring a login, and wait for ELS response. Send CT request to specified N_Port_ID and wait for CT response. Login is required, but LLDD is allowed to manage login and decide whether it stays in place after the request is satisfied. Vendor-Unique request. Allows a LLDD-specific request to be passed to the LLDD, and the passing of a response back to the application. On an fc_rport basis: Send ELS request to nport and wait for ELS response. Send CT request to nport and wait for CT response. The patch also exports several headers from include/scsi such that they can be available to user-space applications: include/scsi/scsi.h include/scsi/scsi_netlink.h include/scsi/scsi_netlink_fc.h include/scsi/scsi_bsg_fc.h For further information, refer to the last RFC: http://marc.info/?l=linux-scsi&m=123436574018579&w=2 Note: Documentation is still spotty and will be added later. [bharrosh@panasas.com: update for new block API] Signed-off-by: James Smart Signed-off-by: James Bottomley --- drivers/scsi/scsi_transport_fc.c | 614 ++++++++++++++++++++++++++++++++++++++- 1 file changed, 613 insertions(+), 1 deletion(-) (limited to 'drivers/scsi') diff --git a/drivers/scsi/scsi_transport_fc.c b/drivers/scsi/scsi_transport_fc.c index a152f89ae51..3f64d93b6c8 100644 --- a/drivers/scsi/scsi_transport_fc.c +++ b/drivers/scsi/scsi_transport_fc.c @@ -35,6 +35,7 @@ #include #include #include +#include #include "scsi_priv.h" #include "scsi_transport_fc_internal.h" @@ -43,6 +44,10 @@ static void fc_vport_sched_delete(struct work_struct *work); static int fc_vport_setup(struct Scsi_Host *shost, int channel, struct device *pdev, struct fc_vport_identifiers *ids, struct fc_vport **vport); +static int fc_bsg_hostadd(struct Scsi_Host *, struct fc_host_attrs *); +static int fc_bsg_rportadd(struct Scsi_Host *, struct fc_rport *); +static void fc_bsg_remove(struct request_queue *); +static void fc_bsg_goose_queue(struct fc_rport *); /* * Redefine so that we can have same named attributes in the @@ -411,13 +416,26 @@ static int fc_host_setup(struct transport_container *tc, struct device *dev, return -ENOMEM; } + fc_bsg_hostadd(shost, fc_host); + /* ignore any bsg add error - we just can't do sgio */ + + return 0; +} + +static int fc_host_remove(struct transport_container *tc, struct device *dev, + struct device *cdev) +{ + struct Scsi_Host *shost = dev_to_shost(dev); + struct fc_host_attrs *fc_host = shost_to_fc_host(shost); + + fc_bsg_remove(fc_host->rqst_q); return 0; } static DECLARE_TRANSPORT_CLASS(fc_host_class, "fc_host", fc_host_setup, - NULL, + fc_host_remove, NULL); /* @@ -2375,6 +2393,7 @@ fc_rport_final_delete(struct work_struct *work) scsi_flush_work(shost); fc_terminate_rport_io(rport); + /* * Cancel any outstanding timers. These should really exist * only when rmmod'ing the LLDD and we're asking for @@ -2407,6 +2426,8 @@ fc_rport_final_delete(struct work_struct *work) (i->f->dev_loss_tmo_callbk)) i->f->dev_loss_tmo_callbk(rport); + fc_bsg_remove(rport->rqst_q); + transport_remove_device(dev); device_del(dev); transport_destroy_device(dev); @@ -2494,6 +2515,9 @@ fc_rport_create(struct Scsi_Host *shost, int channel, transport_add_device(dev); transport_configure_device(dev); + fc_bsg_rportadd(shost, rport); + /* ignore any bsg add error - we just can't do sgio */ + if (rport->roles & FC_PORT_ROLE_FCP_TARGET) { /* initiate a scan of the target */ rport->flags |= FC_RPORT_SCAN_PENDING; @@ -2658,6 +2682,8 @@ fc_remote_port_add(struct Scsi_Host *shost, int channel, spin_unlock_irqrestore(shost->host_lock, flags); + fc_bsg_goose_queue(rport); + return rport; } } @@ -3343,6 +3369,592 @@ fc_vport_sched_delete(struct work_struct *work) } +/* + * BSG support + */ + + +/** + * fc_destroy_bsgjob - routine to teardown/delete a fc bsg job + * @job: fc_bsg_job that is to be torn down + */ +static void +fc_destroy_bsgjob(struct fc_bsg_job *job) +{ + unsigned long flags; + + spin_lock_irqsave(&job->job_lock, flags); + if (job->ref_cnt) { + spin_unlock_irqrestore(&job->job_lock, flags); + return; + } + spin_unlock_irqrestore(&job->job_lock, flags); + + put_device(job->dev); /* release reference for the request */ + + kfree(job->request_payload.sg_list); + kfree(job->reply_payload.sg_list); + kfree(job); +} + + +/** + * fc_bsg_jobdone - completion routine for bsg requests that the LLD has + * completed + * @job: fc_bsg_job that is complete + */ +static void +fc_bsg_jobdone(struct fc_bsg_job *job) +{ + struct request *req = job->req; + struct request *rsp = req->next_rq; + unsigned long flags; + int err; + + spin_lock_irqsave(&job->job_lock, flags); + job->state_flags |= FC_RQST_STATE_DONE; + job->ref_cnt--; + spin_unlock_irqrestore(&job->job_lock, flags); + + err = job->req->errors = job->reply->result; + if (err < 0) + /* we're only returning the result field in the reply */ + job->req->sense_len = sizeof(uint32_t); + else + job->req->sense_len = job->reply_len; + + /* we assume all request payload was transferred, residual == 0 */ + req->resid_len = 0; + + if (rsp) { + WARN_ON(job->reply->reply_payload_rcv_len > rsp->resid_len); + + /* set reply (bidi) residual */ + rsp->resid_len -= min(job->reply->reply_payload_rcv_len, + rsp->resid_len); + } + + blk_end_request_all(req, err); + + fc_destroy_bsgjob(job); +} + + +/** + * fc_bsg_job_timeout - handler for when a bsg request timesout + * @req: request that timed out + */ +static enum blk_eh_timer_return +fc_bsg_job_timeout(struct request *req) +{ + struct fc_bsg_job *job = (void *) req->special; + struct Scsi_Host *shost = job->shost; + struct fc_internal *i = to_fc_internal(shost->transportt); + unsigned long flags; + int err = 0, done = 0; + + if (job->rport && job->rport->port_state == FC_PORTSTATE_BLOCKED) + return BLK_EH_RESET_TIMER; + + spin_lock_irqsave(&job->job_lock, flags); + if (job->state_flags & FC_RQST_STATE_DONE) + done = 1; + else + job->ref_cnt++; + spin_unlock_irqrestore(&job->job_lock, flags); + + if (!done && i->f->bsg_timeout) { + /* call LLDD to abort the i/o as it has timed out */ + err = i->f->bsg_timeout(job); + if (err) + printk(KERN_ERR "ERROR: FC BSG request timeout - LLD " + "abort failed with status %d\n", err); + } + + if (!done) { + spin_lock_irqsave(&job->job_lock, flags); + job->ref_cnt--; + spin_unlock_irqrestore(&job->job_lock, flags); + fc_destroy_bsgjob(job); + } + + /* the blk_end_sync_io() doesn't check the error */ + return BLK_EH_HANDLED; +} + + + +static int +fc_bsg_map_buffer(struct fc_bsg_buffer *buf, struct request *req) +{ + size_t sz = (sizeof(struct scatterlist) * req->nr_phys_segments); + + BUG_ON(!req->nr_phys_segments); + + buf->sg_list = kzalloc(sz, GFP_KERNEL); + if (!buf->sg_list) + return -ENOMEM; + sg_init_table(buf->sg_list, req->nr_phys_segments); + buf->sg_cnt = blk_rq_map_sg(req->q, req, buf->sg_list); + buf->payload_len = blk_rq_bytes(req); + return 0; +} + + +/** + * fc_req_to_bsgjob - Allocate/create the fc_bsg_job structure for the + * bsg request + * @shost: SCSI Host corresponding to the bsg object + * @rport: (optional) FC Remote Port corresponding to the bsg object + * @req: BSG request that needs a job structure + */ +static int +fc_req_to_bsgjob(struct Scsi_Host *shost, struct fc_rport *rport, + struct request *req) +{ + struct fc_internal *i = to_fc_internal(shost->transportt); + struct request *rsp = req->next_rq; + struct fc_bsg_job *job; + int ret; + + BUG_ON(req->special); + + job = kzalloc(sizeof(struct fc_bsg_job) + i->f->dd_bsg_size, + GFP_KERNEL); + if (!job) + return -ENOMEM; + + /* + * Note: this is a bit silly. + * The request gets formatted as a SGIO v4 ioctl request, which + * then gets reformatted as a blk request, which then gets + * reformatted as a fc bsg request. And on completion, we have + * to wrap return results such that SGIO v4 thinks it was a scsi + * status. I hope this was all worth it. + */ + + req->special = job; + job->shost = shost; + job->rport = rport; + job->req = req; + if (i->f->dd_bsg_size) + job->dd_data = (void *)&job[1]; + spin_lock_init(&job->job_lock); + job->request = (struct fc_bsg_request *)req->cmd; + job->request_len = req->cmd_len; + job->reply = req->sense; + job->reply_len = SCSI_SENSE_BUFFERSIZE; /* Size of sense buffer + * allocated */ + if (req->bio) { + ret = fc_bsg_map_buffer(&job->request_payload, req); + if (ret) + goto failjob_rls_job; + } + if (rsp && rsp->bio) { + ret = fc_bsg_map_buffer(&job->reply_payload, rsp); + if (ret) + goto failjob_rls_rqst_payload; + } + job->job_done = fc_bsg_jobdone; + if (rport) + job->dev = &rport->dev; + else + job->dev = &shost->shost_gendev; + get_device(job->dev); /* take a reference for the request */ + + job->ref_cnt = 1; + + return 0; + + +failjob_rls_rqst_payload: + kfree(job->request_payload.sg_list); +failjob_rls_job: + kfree(job); + return -ENOMEM; +} + + +enum fc_dispatch_result { + FC_DISPATCH_BREAK, /* on return, q is locked, break from q loop */ + FC_DISPATCH_LOCKED, /* on return, q is locked, continue on */ + FC_DISPATCH_UNLOCKED, /* on return, q is unlocked, continue on */ +}; + + +/** + * fc_bsg_host_dispatch - process fc host bsg requests and dispatch to LLDD + * @shost: scsi host rport attached to + * @job: bsg job to be processed + */ +static enum fc_dispatch_result +fc_bsg_host_dispatch(struct request_queue *q, struct Scsi_Host *shost, + struct fc_bsg_job *job) +{ + struct fc_internal *i = to_fc_internal(shost->transportt); + int cmdlen = sizeof(uint32_t); /* start with length of msgcode */ + int ret; + + /* Validate the host command */ + switch (job->request->msgcode) { + case FC_BSG_HST_ADD_RPORT: + cmdlen += sizeof(struct fc_bsg_host_add_rport); + break; + + case FC_BSG_HST_DEL_RPORT: + cmdlen += sizeof(struct fc_bsg_host_del_rport); + break; + + case FC_BSG_HST_ELS_NOLOGIN: + cmdlen += sizeof(struct fc_bsg_host_els); + /* there better be a xmt and rcv payloads */ + if ((!job->request_payload.payload_len) || + (!job->reply_payload.payload_len)) { + ret = -EINVAL; + goto fail_host_msg; + } + break; + + case FC_BSG_HST_CT: + cmdlen += sizeof(struct fc_bsg_host_ct); + /* there better be xmt and rcv payloads */ + if ((!job->request_payload.payload_len) || + (!job->reply_payload.payload_len)) { + ret = -EINVAL; + goto fail_host_msg; + } + break; + + case FC_BSG_HST_VENDOR: + cmdlen += sizeof(struct fc_bsg_host_vendor); + if ((shost->hostt->vendor_id == 0L) || + (job->request->rqst_data.h_vendor.vendor_id != + shost->hostt->vendor_id)) { + ret = -ESRCH; + goto fail_host_msg; + } + break; + + default: + ret = -EBADR; + goto fail_host_msg; + } + + /* check if we really have all the request data needed */ + if (job->request_len < cmdlen) { + ret = -ENOMSG; + goto fail_host_msg; + } + + ret = i->f->bsg_request(job); + if (!ret) + return FC_DISPATCH_UNLOCKED; + +fail_host_msg: + /* return the errno failure code as the only status */ + BUG_ON(job->reply_len < sizeof(uint32_t)); + job->reply->result = ret; + job->reply_len = sizeof(uint32_t); + fc_bsg_jobdone(job); + return FC_DISPATCH_UNLOCKED; +} + + +/* + * fc_bsg_goose_queue - restart rport queue in case it was stopped + * @rport: rport to be restarted + */ +static void +fc_bsg_goose_queue(struct fc_rport *rport) +{ + int flagset; + + if (!rport->rqst_q) + return; + + get_device(&rport->dev); + + spin_lock(rport->rqst_q->queue_lock); + flagset = test_bit(QUEUE_FLAG_REENTER, &rport->rqst_q->queue_flags) && + !test_bit(QUEUE_FLAG_REENTER, &rport->rqst_q->queue_flags); + if (flagset) + queue_flag_set(QUEUE_FLAG_REENTER, rport->rqst_q); + __blk_run_queue(rport->rqst_q); + if (flagset) + queue_flag_clear(QUEUE_FLAG_REENTER, rport->rqst_q); + spin_unlock(rport->rqst_q->queue_lock); + + put_device(&rport->dev); +} + + +/** + * fc_bsg_rport_dispatch - process rport bsg requests and dispatch to LLDD + * @shost: scsi host rport attached to + * @rport: rport request destined to + * @job: bsg job to be processed + */ +static enum fc_dispatch_result +fc_bsg_rport_dispatch(struct request_queue *q, struct Scsi_Host *shost, + struct fc_rport *rport, struct fc_bsg_job *job) +{ + struct fc_internal *i = to_fc_internal(shost->transportt); + int cmdlen = sizeof(uint32_t); /* start with length of msgcode */ + int ret; + + /* Validate the rport command */ + switch (job->request->msgcode) { + case FC_BSG_RPT_ELS: + cmdlen += sizeof(struct fc_bsg_rport_els); + goto check_bidi; + + case FC_BSG_RPT_CT: + cmdlen += sizeof(struct fc_bsg_rport_ct); +check_bidi: + /* there better be xmt and rcv payloads */ + if ((!job->request_payload.payload_len) || + (!job->reply_payload.payload_len)) { + ret = -EINVAL; + goto fail_rport_msg; + } + break; + default: + ret = -EBADR; + goto fail_rport_msg; + } + + /* check if we really have all the request data needed */ + if (job->request_len < cmdlen) { + ret = -ENOMSG; + goto fail_rport_msg; + } + + ret = i->f->bsg_request(job); + if (!ret) + return FC_DISPATCH_UNLOCKED; + +fail_rport_msg: + /* return the errno failure code as the only status */ + BUG_ON(job->reply_len < sizeof(uint32_t)); + job->reply->result = ret; + job->reply_len = sizeof(uint32_t); + fc_bsg_jobdone(job); + return FC_DISPATCH_UNLOCKED; +} + + +/** + * fc_bsg_request_handler - generic handler for bsg requests + * @q: request queue to manage + * @shost: Scsi_Host related to the bsg object + * @rport: FC remote port related to the bsg object (optional) + * @dev: device structure for bsg object + */ +static void +fc_bsg_request_handler(struct request_queue *q, struct Scsi_Host *shost, + struct fc_rport *rport, struct device *dev) +{ + struct request *req; + struct fc_bsg_job *job; + enum fc_dispatch_result ret; + + if (!get_device(dev)) + return; + + while (!blk_queue_plugged(q)) { + if (rport && (rport->port_state == FC_PORTSTATE_BLOCKED)) + break; + + req = blk_fetch_request(q); + if (!req) + break; + + if (rport && (rport->port_state != FC_PORTSTATE_ONLINE)) { + req->errors = -ENXIO; + spin_unlock_irq(q->queue_lock); + blk_end_request(req, -ENXIO, blk_rq_bytes(req)); + spin_lock_irq(q->queue_lock); + continue; + } + + spin_unlock_irq(q->queue_lock); + + ret = fc_req_to_bsgjob(shost, rport, req); + if (ret) { + req->errors = ret; + blk_end_request(req, ret, blk_rq_bytes(req)); + spin_lock_irq(q->queue_lock); + continue; + } + + job = req->special; + + /* check if we have the msgcode value at least */ + if (job->request_len < sizeof(uint32_t)) { + BUG_ON(job->reply_len < sizeof(uint32_t)); + job->reply->result = -ENOMSG; + job->reply_len = sizeof(uint32_t); + fc_bsg_jobdone(job); + spin_lock_irq(q->queue_lock); + continue; + } + + /* the dispatch routines will unlock the queue_lock */ + if (rport) + ret = fc_bsg_rport_dispatch(q, shost, rport, job); + else + ret = fc_bsg_host_dispatch(q, shost, job); + + /* did dispatcher hit state that can't process any more */ + if (ret == FC_DISPATCH_BREAK) + break; + + /* did dispatcher had released the lock */ + if (ret == FC_DISPATCH_UNLOCKED) + spin_lock_irq(q->queue_lock); + } + + spin_unlock_irq(q->queue_lock); + put_device(dev); + spin_lock_irq(q->queue_lock); +} + + +/** + * fc_bsg_host_handler - handler for bsg requests for a fc host + * @q: fc host request queue + */ +static void +fc_bsg_host_handler(struct request_queue *q) +{ + struct Scsi_Host *shost = q->queuedata; + + fc_bsg_request_handler(q, shost, NULL, &shost->shost_gendev); +} + + +/** + * fc_bsg_rport_handler - handler for bsg requests for a fc rport + * @q: rport request queue + */ +static void +fc_bsg_rport_handler(struct request_queue *q) +{ + struct fc_rport *rport = q->queuedata; + struct Scsi_Host *shost = rport_to_shost(rport); + + fc_bsg_request_handler(q, shost, rport, &rport->dev); +} + + +/** + * fc_bsg_hostadd - Create and add the bsg hooks so we can receive requests + * @shost: shost for fc_host + * @fc_host: fc_host adding the structures to + */ +static int +fc_bsg_hostadd(struct Scsi_Host *shost, struct fc_host_attrs *fc_host) +{ + struct device *dev = &shost->shost_gendev; + struct fc_internal *i = to_fc_internal(shost->transportt); + struct request_queue *q; + int err; + char bsg_name[BUS_ID_SIZE]; /*20*/ + + fc_host->rqst_q = NULL; + + if (!i->f->bsg_request) + return -ENOTSUPP; + + snprintf(bsg_name, sizeof(bsg_name), + "fc_host%d", shost->host_no); + + q = __scsi_alloc_queue(shost, fc_bsg_host_handler); + if (!q) { + printk(KERN_ERR "fc_host%d: bsg interface failed to " + "initialize - no request queue\n", + shost->host_no); + return -ENOMEM; + } + + q->queuedata = shost; + queue_flag_set_unlocked(QUEUE_FLAG_BIDI, q); + blk_queue_rq_timed_out(q, fc_bsg_job_timeout); + blk_queue_rq_timeout(q, FC_DEFAULT_BSG_TIMEOUT); + + err = bsg_register_queue(q, dev, bsg_name, NULL); + if (err) { + printk(KERN_ERR "fc_host%d: bsg interface failed to " + "initialize - register queue\n", + shost->host_no); + blk_cleanup_queue(q); + return err; + } + + fc_host->rqst_q = q; + return 0; +} + + +/** + * fc_bsg_rportadd - Create and add the bsg hooks so we can receive requests + * @shost: shost that rport is attached to + * @rport: rport that the bsg hooks are being attached to + */ +static int +fc_bsg_rportadd(struct Scsi_Host *shost, struct fc_rport *rport) +{ + struct device *dev = &rport->dev; + struct fc_internal *i = to_fc_internal(shost->transportt); + struct request_queue *q; + int err; + + rport->rqst_q = NULL; + + if (!i->f->bsg_request) + return -ENOTSUPP; + + q = __scsi_alloc_queue(shost, fc_bsg_rport_handler); + if (!q) { + printk(KERN_ERR "%s: bsg interface failed to " + "initialize - no request queue\n", + dev->kobj.name); + return -ENOMEM; + } + + q->queuedata = rport; + queue_flag_set_unlocked(QUEUE_FLAG_BIDI, q); + blk_queue_rq_timed_out(q, fc_bsg_job_timeout); + blk_queue_rq_timeout(q, BLK_DEFAULT_SG_TIMEOUT); + + err = bsg_register_queue(q, dev, NULL, NULL); + if (err) { + printk(KERN_ERR "%s: bsg interface failed to " + "initialize - register queue\n", + dev->kobj.name); + blk_cleanup_queue(q); + return err; + } + + rport->rqst_q = q; + return 0; +} + + +/** + * fc_bsg_remove - Deletes the bsg hooks on fchosts/rports + * @q: the request_queue that is to be torn down. + */ +static void +fc_bsg_remove(struct request_queue *q) +{ + if (q) { + bsg_unregister_queue(q); + blk_cleanup_queue(q); + } +} + + /* Original Author: Martin Hicks */ MODULE_AUTHOR("James Smart"); MODULE_DESCRIPTION("FC Transport Attributes"); -- cgit v1.2.3