summaryrefslogtreecommitdiffstats
path: root/drivers/scsi/libfc/fc_disc.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/scsi/libfc/fc_disc.c')
-rw-r--r--drivers/scsi/libfc/fc_disc.c746
1 files changed, 746 insertions, 0 deletions
diff --git a/drivers/scsi/libfc/fc_disc.c b/drivers/scsi/libfc/fc_disc.c
new file mode 100644
index 0000000000..384f48ff64
--- /dev/null
+++ b/drivers/scsi/libfc/fc_disc.c
@@ -0,0 +1,746 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright(c) 2007 - 2008 Intel Corporation. All rights reserved.
+ *
+ * Maintained at www.Open-FCoE.org
+ */
+
+/*
+ * Target Discovery
+ *
+ * This block discovers all FC-4 remote ports, including FCP initiators. It
+ * also handles RSCN events and re-discovery if necessary.
+ */
+
+/*
+ * DISC LOCKING
+ *
+ * The disc mutex is can be locked when acquiring rport locks, but may not
+ * be held when acquiring the lport lock. Refer to fc_lport.c for more
+ * details.
+ */
+
+#include <linux/timer.h>
+#include <linux/slab.h>
+#include <linux/err.h>
+#include <linux/export.h>
+#include <linux/list.h>
+
+#include <asm/unaligned.h>
+
+#include <scsi/fc/fc_gs.h>
+
+#include <scsi/libfc.h>
+
+#include "fc_libfc.h"
+
+#define FC_DISC_RETRY_LIMIT 3 /* max retries */
+#define FC_DISC_RETRY_DELAY 500UL /* (msecs) delay */
+
+static void fc_disc_gpn_ft_req(struct fc_disc *);
+static void fc_disc_gpn_ft_resp(struct fc_seq *, struct fc_frame *, void *);
+static void fc_disc_done(struct fc_disc *, enum fc_disc_event);
+static void fc_disc_timeout(struct work_struct *);
+static int fc_disc_single(struct fc_lport *, struct fc_disc_port *);
+static void fc_disc_restart(struct fc_disc *);
+
+/**
+ * fc_disc_stop_rports() - Delete all the remote ports associated with the lport
+ * @disc: The discovery job to stop remote ports on
+ */
+static void fc_disc_stop_rports(struct fc_disc *disc)
+{
+ struct fc_rport_priv *rdata;
+
+ lockdep_assert_held(&disc->disc_mutex);
+
+ list_for_each_entry(rdata, &disc->rports, peers) {
+ if (kref_get_unless_zero(&rdata->kref)) {
+ fc_rport_logoff(rdata);
+ kref_put(&rdata->kref, fc_rport_destroy);
+ }
+ }
+}
+
+/**
+ * fc_disc_recv_rscn_req() - Handle Registered State Change Notification (RSCN)
+ * @disc: The discovery object to which the RSCN applies
+ * @fp: The RSCN frame
+ */
+static void fc_disc_recv_rscn_req(struct fc_disc *disc, struct fc_frame *fp)
+{
+ struct fc_lport *lport;
+ struct fc_els_rscn *rp;
+ struct fc_els_rscn_page *pp;
+ struct fc_seq_els_data rjt_data;
+ unsigned int len;
+ int redisc = 0;
+ enum fc_els_rscn_addr_fmt fmt;
+ LIST_HEAD(disc_ports);
+ struct fc_disc_port *dp, *next;
+
+ lockdep_assert_held(&disc->disc_mutex);
+
+ lport = fc_disc_lport(disc);
+
+ FC_DISC_DBG(disc, "Received an RSCN event\n");
+
+ /* make sure the frame contains an RSCN message */
+ rp = fc_frame_payload_get(fp, sizeof(*rp));
+ if (!rp)
+ goto reject;
+ /* make sure the page length is as expected (4 bytes) */
+ if (rp->rscn_page_len != sizeof(*pp))
+ goto reject;
+ /* get the RSCN payload length */
+ len = ntohs(rp->rscn_plen);
+ if (len < sizeof(*rp))
+ goto reject;
+ /* make sure the frame contains the expected payload */
+ rp = fc_frame_payload_get(fp, len);
+ if (!rp)
+ goto reject;
+ /* payload must be a multiple of the RSCN page size */
+ len -= sizeof(*rp);
+ if (len % sizeof(*pp))
+ goto reject;
+
+ for (pp = (void *)(rp + 1); len > 0; len -= sizeof(*pp), pp++) {
+ fmt = pp->rscn_page_flags >> ELS_RSCN_ADDR_FMT_BIT;
+ fmt &= ELS_RSCN_ADDR_FMT_MASK;
+ /*
+ * if we get an address format other than port
+ * (area, domain, fabric), then do a full discovery
+ */
+ switch (fmt) {
+ case ELS_ADDR_FMT_PORT:
+ FC_DISC_DBG(disc, "Port address format for port "
+ "(%6.6x)\n", ntoh24(pp->rscn_fid));
+ dp = kzalloc(sizeof(*dp), GFP_KERNEL);
+ if (!dp) {
+ redisc = 1;
+ break;
+ }
+ dp->lp = lport;
+ dp->port_id = ntoh24(pp->rscn_fid);
+ list_add_tail(&dp->peers, &disc_ports);
+ break;
+ case ELS_ADDR_FMT_AREA:
+ case ELS_ADDR_FMT_DOM:
+ case ELS_ADDR_FMT_FAB:
+ default:
+ FC_DISC_DBG(disc, "Address format is (%d)\n", fmt);
+ redisc = 1;
+ break;
+ }
+ }
+ fc_seq_els_rsp_send(fp, ELS_LS_ACC, NULL);
+
+ /*
+ * If not doing a complete rediscovery, do GPN_ID on
+ * the individual ports mentioned in the list.
+ * If any of these get an error, do a full rediscovery.
+ * In any case, go through the list and free the entries.
+ */
+ list_for_each_entry_safe(dp, next, &disc_ports, peers) {
+ list_del(&dp->peers);
+ if (!redisc)
+ redisc = fc_disc_single(lport, dp);
+ kfree(dp);
+ }
+ if (redisc) {
+ FC_DISC_DBG(disc, "RSCN received: rediscovering\n");
+ fc_disc_restart(disc);
+ } else {
+ FC_DISC_DBG(disc, "RSCN received: not rediscovering. "
+ "redisc %d state %d in_prog %d\n",
+ redisc, lport->state, disc->pending);
+ }
+ fc_frame_free(fp);
+ return;
+reject:
+ FC_DISC_DBG(disc, "Received a bad RSCN frame\n");
+ rjt_data.reason = ELS_RJT_LOGIC;
+ rjt_data.explan = ELS_EXPL_NONE;
+ fc_seq_els_rsp_send(fp, ELS_LS_RJT, &rjt_data);
+ fc_frame_free(fp);
+}
+
+/**
+ * fc_disc_recv_req() - Handle incoming requests
+ * @lport: The local port receiving the request
+ * @fp: The request frame
+ *
+ * Locking Note: This function is called from the EM and will lock
+ * the disc_mutex before calling the handler for the
+ * request.
+ */
+static void fc_disc_recv_req(struct fc_lport *lport, struct fc_frame *fp)
+{
+ u8 op;
+ struct fc_disc *disc = &lport->disc;
+
+ op = fc_frame_payload_op(fp);
+ switch (op) {
+ case ELS_RSCN:
+ mutex_lock(&disc->disc_mutex);
+ fc_disc_recv_rscn_req(disc, fp);
+ mutex_unlock(&disc->disc_mutex);
+ break;
+ default:
+ FC_DISC_DBG(disc, "Received an unsupported request, "
+ "the opcode is (%x)\n", op);
+ fc_frame_free(fp);
+ break;
+ }
+}
+
+/**
+ * fc_disc_restart() - Restart discovery
+ * @disc: The discovery object to be restarted
+ */
+static void fc_disc_restart(struct fc_disc *disc)
+{
+ lockdep_assert_held(&disc->disc_mutex);
+
+ if (!disc->disc_callback)
+ return;
+
+ FC_DISC_DBG(disc, "Restarting discovery\n");
+
+ disc->requested = 1;
+ if (disc->pending)
+ return;
+
+ /*
+ * Advance disc_id. This is an arbitrary non-zero number that will
+ * match the value in the fc_rport_priv after discovery for all
+ * freshly-discovered remote ports. Avoid wrapping to zero.
+ */
+ disc->disc_id = (disc->disc_id + 2) | 1;
+ disc->retry_count = 0;
+ fc_disc_gpn_ft_req(disc);
+}
+
+/**
+ * fc_disc_start() - Start discovery on a local port
+ * @lport: The local port to have discovery started on
+ * @disc_callback: Callback function to be called when discovery is complete
+ */
+static void fc_disc_start(void (*disc_callback)(struct fc_lport *,
+ enum fc_disc_event),
+ struct fc_lport *lport)
+{
+ struct fc_disc *disc = &lport->disc;
+
+ /*
+ * At this point we may have a new disc job or an existing
+ * one. Either way, let's lock when we make changes to it
+ * and send the GPN_FT request.
+ */
+ mutex_lock(&disc->disc_mutex);
+ disc->disc_callback = disc_callback;
+ fc_disc_restart(disc);
+ mutex_unlock(&disc->disc_mutex);
+}
+
+/**
+ * fc_disc_done() - Discovery has been completed
+ * @disc: The discovery context
+ * @event: The discovery completion status
+ */
+static void fc_disc_done(struct fc_disc *disc, enum fc_disc_event event)
+{
+ struct fc_lport *lport = fc_disc_lport(disc);
+ struct fc_rport_priv *rdata;
+
+ lockdep_assert_held(&disc->disc_mutex);
+ FC_DISC_DBG(disc, "Discovery complete\n");
+
+ disc->pending = 0;
+ if (disc->requested) {
+ fc_disc_restart(disc);
+ return;
+ }
+
+ /*
+ * Go through all remote ports. If they were found in the latest
+ * discovery, reverify or log them in. Otherwise, log them out.
+ * Skip ports which were never discovered. These are the dNS port
+ * and ports which were created by PLOGI.
+ *
+ * We don't need to use the _rcu variant here as the rport list
+ * is protected by the disc mutex which is already held on entry.
+ */
+ list_for_each_entry(rdata, &disc->rports, peers) {
+ if (!kref_get_unless_zero(&rdata->kref))
+ continue;
+ if (rdata->disc_id) {
+ if (rdata->disc_id == disc->disc_id)
+ fc_rport_login(rdata);
+ else
+ fc_rport_logoff(rdata);
+ }
+ kref_put(&rdata->kref, fc_rport_destroy);
+ }
+ mutex_unlock(&disc->disc_mutex);
+ disc->disc_callback(lport, event);
+ mutex_lock(&disc->disc_mutex);
+}
+
+/**
+ * fc_disc_error() - Handle error on dNS request
+ * @disc: The discovery context
+ * @fp: The error code encoded as a frame pointer
+ */
+static void fc_disc_error(struct fc_disc *disc, struct fc_frame *fp)
+{
+ struct fc_lport *lport = fc_disc_lport(disc);
+ unsigned long delay = 0;
+
+ FC_DISC_DBG(disc, "Error %d, retries %d/%d\n",
+ PTR_ERR_OR_ZERO(fp), disc->retry_count,
+ FC_DISC_RETRY_LIMIT);
+
+ if (!fp || PTR_ERR(fp) == -FC_EX_TIMEOUT) {
+ /*
+ * Memory allocation failure, or the exchange timed out,
+ * retry after delay.
+ */
+ if (disc->retry_count < FC_DISC_RETRY_LIMIT) {
+ /* go ahead and retry */
+ if (!fp)
+ delay = msecs_to_jiffies(FC_DISC_RETRY_DELAY);
+ else {
+ delay = msecs_to_jiffies(lport->e_d_tov);
+
+ /* timeout faster first time */
+ if (!disc->retry_count)
+ delay /= 4;
+ }
+ disc->retry_count++;
+ schedule_delayed_work(&disc->disc_work, delay);
+ } else
+ fc_disc_done(disc, DISC_EV_FAILED);
+ } else if (PTR_ERR(fp) == -FC_EX_CLOSED) {
+ /*
+ * if discovery fails due to lport reset, clear
+ * pending flag so that subsequent discovery can
+ * continue
+ */
+ disc->pending = 0;
+ }
+}
+
+/**
+ * fc_disc_gpn_ft_req() - Send Get Port Names by FC-4 type (GPN_FT) request
+ * @disc: The discovery context
+ */
+static void fc_disc_gpn_ft_req(struct fc_disc *disc)
+{
+ struct fc_frame *fp;
+ struct fc_lport *lport = fc_disc_lport(disc);
+
+ lockdep_assert_held(&disc->disc_mutex);
+
+ WARN_ON(!fc_lport_test_ready(lport));
+
+ disc->pending = 1;
+ disc->requested = 0;
+
+ disc->buf_len = 0;
+ disc->seq_count = 0;
+ fp = fc_frame_alloc(lport,
+ sizeof(struct fc_ct_hdr) +
+ sizeof(struct fc_ns_gid_ft));
+ if (!fp)
+ goto err;
+
+ if (lport->tt.elsct_send(lport, 0, fp,
+ FC_NS_GPN_FT,
+ fc_disc_gpn_ft_resp,
+ disc, 3 * lport->r_a_tov))
+ return;
+err:
+ fc_disc_error(disc, NULL);
+}
+
+/**
+ * fc_disc_gpn_ft_parse() - Parse the body of the dNS GPN_FT response.
+ * @disc: The discovery context
+ * @buf: The GPN_FT response buffer
+ * @len: The size of response buffer
+ *
+ * Goes through the list of IDs and names resulting from a request.
+ */
+static int fc_disc_gpn_ft_parse(struct fc_disc *disc, void *buf, size_t len)
+{
+ struct fc_lport *lport;
+ struct fc_gpn_ft_resp *np;
+ char *bp;
+ size_t plen;
+ size_t tlen;
+ int error = 0;
+ struct fc_rport_identifiers ids;
+ struct fc_rport_priv *rdata;
+
+ lport = fc_disc_lport(disc);
+ disc->seq_count++;
+
+ /*
+ * Handle partial name record left over from previous call.
+ */
+ bp = buf;
+ plen = len;
+ np = (struct fc_gpn_ft_resp *)bp;
+ tlen = disc->buf_len;
+ disc->buf_len = 0;
+ if (tlen) {
+ WARN_ON(tlen >= sizeof(*np));
+ plen = sizeof(*np) - tlen;
+ WARN_ON(plen <= 0);
+ WARN_ON(plen >= sizeof(*np));
+ if (plen > len)
+ plen = len;
+ np = &disc->partial_buf;
+ memcpy((char *)np + tlen, bp, plen);
+
+ /*
+ * Set bp so that the loop below will advance it to the
+ * first valid full name element.
+ */
+ bp -= tlen;
+ len += tlen;
+ plen += tlen;
+ disc->buf_len = (unsigned char) plen;
+ if (plen == sizeof(*np))
+ disc->buf_len = 0;
+ }
+
+ /*
+ * Handle full name records, including the one filled from above.
+ * Normally, np == bp and plen == len, but from the partial case above,
+ * bp, len describe the overall buffer, and np, plen describe the
+ * partial buffer, which if would usually be full now.
+ * After the first time through the loop, things return to "normal".
+ */
+ while (plen >= sizeof(*np)) {
+ ids.port_id = ntoh24(np->fp_fid);
+ ids.port_name = ntohll(np->fp_wwpn);
+
+ if (ids.port_id != lport->port_id &&
+ ids.port_name != lport->wwpn) {
+ rdata = fc_rport_create(lport, ids.port_id);
+ if (rdata) {
+ rdata->ids.port_name = ids.port_name;
+ rdata->disc_id = disc->disc_id;
+ } else {
+ printk(KERN_WARNING "libfc: Failed to allocate "
+ "memory for the newly discovered port "
+ "(%6.6x)\n", ids.port_id);
+ error = -ENOMEM;
+ }
+ }
+
+ if (np->fp_flags & FC_NS_FID_LAST) {
+ fc_disc_done(disc, DISC_EV_SUCCESS);
+ len = 0;
+ break;
+ }
+ len -= sizeof(*np);
+ bp += sizeof(*np);
+ np = (struct fc_gpn_ft_resp *)bp;
+ plen = len;
+ }
+
+ /*
+ * Save any partial record at the end of the buffer for next time.
+ */
+ if (error == 0 && len > 0 && len < sizeof(*np)) {
+ if (np != &disc->partial_buf) {
+ FC_DISC_DBG(disc, "Partial buffer remains "
+ "for discovery\n");
+ memcpy(&disc->partial_buf, np, len);
+ }
+ disc->buf_len = (unsigned char) len;
+ }
+ return error;
+}
+
+/**
+ * fc_disc_timeout() - Handler for discovery timeouts
+ * @work: Structure holding discovery context that needs to retry discovery
+ */
+static void fc_disc_timeout(struct work_struct *work)
+{
+ struct fc_disc *disc = container_of(work,
+ struct fc_disc,
+ disc_work.work);
+ mutex_lock(&disc->disc_mutex);
+ fc_disc_gpn_ft_req(disc);
+ mutex_unlock(&disc->disc_mutex);
+}
+
+/**
+ * fc_disc_gpn_ft_resp() - Handle a response frame from Get Port Names (GPN_FT)
+ * @sp: The sequence that the GPN_FT response was received on
+ * @fp: The GPN_FT response frame
+ * @disc_arg: The discovery context
+ *
+ * Locking Note: This function is called without disc mutex held, and
+ * should do all its processing with the mutex held
+ */
+static void fc_disc_gpn_ft_resp(struct fc_seq *sp, struct fc_frame *fp,
+ void *disc_arg)
+{
+ struct fc_disc *disc = disc_arg;
+ struct fc_ct_hdr *cp;
+ struct fc_frame_header *fh;
+ enum fc_disc_event event = DISC_EV_NONE;
+ unsigned int seq_cnt;
+ unsigned int len;
+ int error = 0;
+
+ mutex_lock(&disc->disc_mutex);
+ FC_DISC_DBG(disc, "Received a GPN_FT response\n");
+
+ if (IS_ERR(fp)) {
+ fc_disc_error(disc, fp);
+ mutex_unlock(&disc->disc_mutex);
+ return;
+ }
+
+ WARN_ON(!fc_frame_is_linear(fp)); /* buffer must be contiguous */
+ fh = fc_frame_header_get(fp);
+ len = fr_len(fp) - sizeof(*fh);
+ seq_cnt = ntohs(fh->fh_seq_cnt);
+ if (fr_sof(fp) == FC_SOF_I3 && seq_cnt == 0 && disc->seq_count == 0) {
+ cp = fc_frame_payload_get(fp, sizeof(*cp));
+ if (!cp) {
+ FC_DISC_DBG(disc, "GPN_FT response too short, len %d\n",
+ fr_len(fp));
+ event = DISC_EV_FAILED;
+ } else if (ntohs(cp->ct_cmd) == FC_FS_ACC) {
+
+ /* Accepted, parse the response. */
+ len -= sizeof(*cp);
+ error = fc_disc_gpn_ft_parse(disc, cp + 1, len);
+ } else if (ntohs(cp->ct_cmd) == FC_FS_RJT) {
+ FC_DISC_DBG(disc, "GPN_FT rejected reason %x exp %x "
+ "(check zoning)\n", cp->ct_reason,
+ cp->ct_explan);
+ event = DISC_EV_FAILED;
+ if (cp->ct_reason == FC_FS_RJT_UNABL &&
+ cp->ct_explan == FC_FS_EXP_FTNR)
+ event = DISC_EV_SUCCESS;
+ } else {
+ FC_DISC_DBG(disc, "GPN_FT unexpected response code "
+ "%x\n", ntohs(cp->ct_cmd));
+ event = DISC_EV_FAILED;
+ }
+ } else if (fr_sof(fp) == FC_SOF_N3 && seq_cnt == disc->seq_count) {
+ error = fc_disc_gpn_ft_parse(disc, fh + 1, len);
+ } else {
+ FC_DISC_DBG(disc, "GPN_FT unexpected frame - out of sequence? "
+ "seq_cnt %x expected %x sof %x eof %x\n",
+ seq_cnt, disc->seq_count, fr_sof(fp), fr_eof(fp));
+ event = DISC_EV_FAILED;
+ }
+ if (error)
+ fc_disc_error(disc, ERR_PTR(error));
+ else if (event != DISC_EV_NONE)
+ fc_disc_done(disc, event);
+ fc_frame_free(fp);
+ mutex_unlock(&disc->disc_mutex);
+}
+
+/**
+ * fc_disc_gpn_id_resp() - Handle a response frame from Get Port Names (GPN_ID)
+ * @sp: The sequence the GPN_ID is on
+ * @fp: The response frame
+ * @rdata_arg: The remote port that sent the GPN_ID response
+ *
+ * Locking Note: This function is called without disc mutex held.
+ */
+static void fc_disc_gpn_id_resp(struct fc_seq *sp, struct fc_frame *fp,
+ void *rdata_arg)
+{
+ struct fc_rport_priv *rdata = rdata_arg;
+ struct fc_rport_priv *new_rdata;
+ struct fc_lport *lport;
+ struct fc_disc *disc;
+ struct fc_ct_hdr *cp;
+ struct fc_ns_gid_pn *pn;
+ u64 port_name;
+
+ lport = rdata->local_port;
+ disc = &lport->disc;
+
+ if (PTR_ERR(fp) == -FC_EX_CLOSED)
+ goto out;
+ if (IS_ERR(fp)) {
+ mutex_lock(&disc->disc_mutex);
+ fc_disc_restart(disc);
+ mutex_unlock(&disc->disc_mutex);
+ goto out;
+ }
+
+ cp = fc_frame_payload_get(fp, sizeof(*cp));
+ if (!cp)
+ goto redisc;
+ if (ntohs(cp->ct_cmd) == FC_FS_ACC) {
+ if (fr_len(fp) < sizeof(struct fc_frame_header) +
+ sizeof(*cp) + sizeof(*pn))
+ goto redisc;
+ pn = (struct fc_ns_gid_pn *)(cp + 1);
+ port_name = get_unaligned_be64(&pn->fn_wwpn);
+ mutex_lock(&rdata->rp_mutex);
+ if (rdata->ids.port_name == -1)
+ rdata->ids.port_name = port_name;
+ else if (rdata->ids.port_name != port_name) {
+ FC_DISC_DBG(disc, "GPN_ID accepted. WWPN changed. "
+ "Port-id %6.6x wwpn %16.16llx\n",
+ rdata->ids.port_id, port_name);
+ mutex_unlock(&rdata->rp_mutex);
+ fc_rport_logoff(rdata);
+ mutex_lock(&lport->disc.disc_mutex);
+ new_rdata = fc_rport_create(lport, rdata->ids.port_id);
+ mutex_unlock(&lport->disc.disc_mutex);
+ if (new_rdata) {
+ new_rdata->disc_id = disc->disc_id;
+ fc_rport_login(new_rdata);
+ }
+ goto free_fp;
+ }
+ rdata->disc_id = disc->disc_id;
+ mutex_unlock(&rdata->rp_mutex);
+ fc_rport_login(rdata);
+ } else if (ntohs(cp->ct_cmd) == FC_FS_RJT) {
+ FC_DISC_DBG(disc, "GPN_ID rejected reason %x exp %x\n",
+ cp->ct_reason, cp->ct_explan);
+ fc_rport_logoff(rdata);
+ } else {
+ FC_DISC_DBG(disc, "GPN_ID unexpected response code %x\n",
+ ntohs(cp->ct_cmd));
+redisc:
+ mutex_lock(&disc->disc_mutex);
+ fc_disc_restart(disc);
+ mutex_unlock(&disc->disc_mutex);
+ }
+free_fp:
+ fc_frame_free(fp);
+out:
+ kref_put(&rdata->kref, fc_rport_destroy);
+}
+
+/**
+ * fc_disc_gpn_id_req() - Send Get Port Names by ID (GPN_ID) request
+ * @lport: The local port to initiate discovery on
+ * @rdata: remote port private data
+ *
+ * On failure, an error code is returned.
+ */
+static int fc_disc_gpn_id_req(struct fc_lport *lport,
+ struct fc_rport_priv *rdata)
+{
+ struct fc_frame *fp;
+
+ lockdep_assert_held(&lport->disc.disc_mutex);
+ fp = fc_frame_alloc(lport, sizeof(struct fc_ct_hdr) +
+ sizeof(struct fc_ns_fid));
+ if (!fp)
+ return -ENOMEM;
+ if (!lport->tt.elsct_send(lport, rdata->ids.port_id, fp, FC_NS_GPN_ID,
+ fc_disc_gpn_id_resp, rdata,
+ 3 * lport->r_a_tov))
+ return -ENOMEM;
+ kref_get(&rdata->kref);
+ return 0;
+}
+
+/**
+ * fc_disc_single() - Discover the directory information for a single target
+ * @lport: The local port the remote port is associated with
+ * @dp: The port to rediscover
+ */
+static int fc_disc_single(struct fc_lport *lport, struct fc_disc_port *dp)
+{
+ struct fc_rport_priv *rdata;
+
+ lockdep_assert_held(&lport->disc.disc_mutex);
+
+ rdata = fc_rport_create(lport, dp->port_id);
+ if (!rdata)
+ return -ENOMEM;
+ rdata->disc_id = 0;
+ return fc_disc_gpn_id_req(lport, rdata);
+}
+
+/**
+ * fc_disc_stop() - Stop discovery for a given lport
+ * @lport: The local port that discovery should stop on
+ */
+static void fc_disc_stop(struct fc_lport *lport)
+{
+ struct fc_disc *disc = &lport->disc;
+
+ if (disc->pending)
+ cancel_delayed_work_sync(&disc->disc_work);
+ mutex_lock(&disc->disc_mutex);
+ fc_disc_stop_rports(disc);
+ mutex_unlock(&disc->disc_mutex);
+}
+
+/**
+ * fc_disc_stop_final() - Stop discovery for a given lport
+ * @lport: The lport that discovery should stop on
+ *
+ * This function will block until discovery has been
+ * completely stopped and all rports have been deleted.
+ */
+static void fc_disc_stop_final(struct fc_lport *lport)
+{
+ fc_disc_stop(lport);
+ fc_rport_flush_queue();
+}
+
+/**
+ * fc_disc_config() - Configure the discovery layer for a local port
+ * @lport: The local port that needs the discovery layer to be configured
+ * @priv: Private data structre for users of the discovery layer
+ */
+void fc_disc_config(struct fc_lport *lport, void *priv)
+{
+ struct fc_disc *disc;
+
+ if (!lport->tt.disc_start)
+ lport->tt.disc_start = fc_disc_start;
+
+ if (!lport->tt.disc_stop)
+ lport->tt.disc_stop = fc_disc_stop;
+
+ if (!lport->tt.disc_stop_final)
+ lport->tt.disc_stop_final = fc_disc_stop_final;
+
+ if (!lport->tt.disc_recv_req)
+ lport->tt.disc_recv_req = fc_disc_recv_req;
+
+ disc = &lport->disc;
+
+ disc->priv = priv;
+}
+EXPORT_SYMBOL(fc_disc_config);
+
+/**
+ * fc_disc_init() - Initialize the discovery layer for a local port
+ * @lport: The local port that needs the discovery layer to be initialized
+ */
+void fc_disc_init(struct fc_lport *lport)
+{
+ struct fc_disc *disc = &lport->disc;
+
+ INIT_DELAYED_WORK(&disc->disc_work, fc_disc_timeout);
+ mutex_init(&disc->disc_mutex);
+ INIT_LIST_HEAD(&disc->rports);
+}
+EXPORT_SYMBOL(fc_disc_init);
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-02 01:54:17 +0000