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path: root/drivers/scsi/libfc/fc_disc.c
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Diffstat (limited to 'drivers/scsi/libfc/fc_disc.c')
-rw-r--r--drivers/scsi/libfc/fc_disc.c845
1 files changed, 845 insertions, 0 deletions
diff --git a/drivers/scsi/libfc/fc_disc.c b/drivers/scsi/libfc/fc_disc.c
new file mode 100644
index 000000000000..dd1564c9e04a
--- /dev/null
+++ b/drivers/scsi/libfc/fc_disc.c
@@ -0,0 +1,845 @@
+/*
+ * Copyright(c) 2007 - 2008 Intel Corporation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * 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/err.h>
+#include <asm/unaligned.h>
+
+#include <scsi/fc/fc_gs.h>
+
+#include <scsi/libfc.h>
+
+#define FC_DISC_RETRY_LIMIT 3 /* max retries */
+#define FC_DISC_RETRY_DELAY 500UL /* (msecs) delay */
+
+#define FC_DISC_DELAY 3
+
+static int fc_disc_debug;
+
+#define FC_DEBUG_DISC(fmt...) \
+ do { \
+ if (fc_disc_debug) \
+ FC_DBG(fmt); \
+ } while (0)
+
+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 int fc_disc_new_target(struct fc_disc *, struct fc_rport *,
+ struct fc_rport_identifiers *);
+static void fc_disc_del_target(struct fc_disc *, struct fc_rport *);
+static void fc_disc_done(struct fc_disc *);
+static void fc_disc_timeout(struct work_struct *);
+static void fc_disc_single(struct fc_disc *, struct fc_disc_port *);
+static void fc_disc_restart(struct fc_disc *);
+
+/**
+ * fc_disc_lookup_rport - lookup a remote port by port_id
+ * @lport: Fibre Channel host port instance
+ * @port_id: remote port port_id to match
+ */
+struct fc_rport *fc_disc_lookup_rport(const struct fc_lport *lport,
+ u32 port_id)
+{
+ const struct fc_disc *disc = &lport->disc;
+ struct fc_rport *rport, *found = NULL;
+ struct fc_rport_libfc_priv *rdata;
+ int disc_found = 0;
+
+ list_for_each_entry(rdata, &disc->rports, peers) {
+ rport = PRIV_TO_RPORT(rdata);
+ if (rport->port_id == port_id) {
+ disc_found = 1;
+ found = rport;
+ break;
+ }
+ }
+
+ if (!disc_found)
+ found = NULL;
+
+ return found;
+}
+
+/**
+ * fc_disc_stop_rports - delete all the remote ports associated with the lport
+ * @disc: The discovery job to stop rports on
+ *
+ * Locking Note: This function expects that the lport mutex is locked before
+ * calling it.
+ */
+void fc_disc_stop_rports(struct fc_disc *disc)
+{
+ struct fc_lport *lport;
+ struct fc_rport *rport;
+ struct fc_rport_libfc_priv *rdata, *next;
+
+ lport = disc->lport;
+
+ mutex_lock(&disc->disc_mutex);
+ list_for_each_entry_safe(rdata, next, &disc->rports, peers) {
+ rport = PRIV_TO_RPORT(rdata);
+ list_del(&rdata->peers);
+ lport->tt.rport_logoff(rport);
+ }
+
+ mutex_unlock(&disc->disc_mutex);
+}
+
+/**
+ * fc_disc_rport_callback - Event handler for rport events
+ * @lport: The lport which is receiving the event
+ * @rport: The rport which the event has occured on
+ * @event: The event that occured
+ *
+ * Locking Note: The rport lock should not be held when calling
+ * this function.
+ */
+static void fc_disc_rport_callback(struct fc_lport *lport,
+ struct fc_rport *rport,
+ enum fc_rport_event event)
+{
+ struct fc_rport_libfc_priv *rdata = rport->dd_data;
+ struct fc_disc *disc = &lport->disc;
+ int found = 0;
+
+ FC_DEBUG_DISC("Received a %d event for port (%6x)\n", event,
+ rport->port_id);
+
+ if (event == RPORT_EV_CREATED) {
+ if (disc) {
+ found = 1;
+ mutex_lock(&disc->disc_mutex);
+ list_add_tail(&rdata->peers, &disc->rports);
+ mutex_unlock(&disc->disc_mutex);
+ }
+ }
+
+ if (!found)
+ FC_DEBUG_DISC("The rport (%6x) is not maintained "
+ "by the discovery layer\n", rport->port_id);
+}
+
+/**
+ * fc_disc_recv_rscn_req - Handle Registered State Change Notification (RSCN)
+ * @sp: Current sequence of the RSCN exchange
+ * @fp: RSCN Frame
+ * @lport: Fibre Channel host port instance
+ *
+ * Locking Note: This function expects that the disc_mutex is locked
+ * before it is called.
+ */
+static void fc_disc_recv_rscn_req(struct fc_seq *sp, struct fc_frame *fp,
+ struct fc_disc *disc)
+{
+ struct fc_lport *lport;
+ struct fc_rport *rport;
+ struct fc_rport_libfc_priv *rdata;
+ 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_ev_qual ev_qual;
+ enum fc_els_rscn_addr_fmt fmt;
+ LIST_HEAD(disc_ports);
+ struct fc_disc_port *dp, *next;
+
+ lport = disc->lport;
+
+ FC_DEBUG_DISC("Received an RSCN event on port (%6x)\n",
+ fc_host_port_id(lport->host));
+
+ /* 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++) {
+ ev_qual = pp->rscn_page_flags >> ELS_RSCN_EV_QUAL_BIT;
+ ev_qual &= ELS_RSCN_EV_QUAL_MASK;
+ 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_DEBUG_DISC("Port address format for port (%6x)\n",
+ ntoh24(pp->rscn_fid));
+ dp = kzalloc(sizeof(*dp), GFP_KERNEL);
+ if (!dp) {
+ redisc = 1;
+ break;
+ }
+ dp->lp = lport;
+ dp->ids.port_id = ntoh24(pp->rscn_fid);
+ dp->ids.port_name = -1;
+ dp->ids.node_name = -1;
+ dp->ids.roles = FC_RPORT_ROLE_UNKNOWN;
+ 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_DEBUG_DISC("Address format is (%d)\n", fmt);
+ redisc = 1;
+ break;
+ }
+ }
+ lport->tt.seq_els_rsp_send(sp, ELS_LS_ACC, NULL);
+ if (redisc) {
+ FC_DEBUG_DISC("RSCN received: rediscovering\n");
+ fc_disc_restart(disc);
+ } else {
+ FC_DEBUG_DISC("RSCN received: not rediscovering. "
+ "redisc %d state %d in_prog %d\n",
+ redisc, lport->state, disc->pending);
+ list_for_each_entry_safe(dp, next, &disc_ports, peers) {
+ list_del(&dp->peers);
+ rport = lport->tt.rport_lookup(lport, dp->ids.port_id);
+ if (rport) {
+ rdata = RPORT_TO_PRIV(rport);
+ list_del(&rdata->peers);
+ lport->tt.rport_logoff(rport);
+ }
+ fc_disc_single(disc, dp);
+ }
+ }
+ fc_frame_free(fp);
+ return;
+reject:
+ FC_DEBUG_DISC("Received a bad RSCN frame\n");
+ rjt_data.fp = NULL;
+ rjt_data.reason = ELS_RJT_LOGIC;
+ rjt_data.explan = ELS_EXPL_NONE;
+ lport->tt.seq_els_rsp_send(sp, ELS_LS_RJT, &rjt_data);
+ fc_frame_free(fp);
+}
+
+/**
+ * fc_disc_recv_req - Handle incoming requests
+ * @sp: Current sequence of the request exchange
+ * @fp: The frame
+ * @lport: The FC local port
+ *
+ * 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_seq *sp, struct fc_frame *fp,
+ struct fc_lport *lport)
+{
+ 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(sp, fp, disc);
+ mutex_unlock(&disc->disc_mutex);
+ break;
+ default:
+ FC_DBG("Received an unsupported request. opcode (%x)\n", op);
+ break;
+ }
+}
+
+/**
+ * fc_disc_restart - Restart discovery
+ * @lport: FC discovery context
+ *
+ * Locking Note: This function expects that the disc mutex
+ * is already locked.
+ */
+static void fc_disc_restart(struct fc_disc *disc)
+{
+ struct fc_rport *rport;
+ struct fc_rport_libfc_priv *rdata, *next;
+ struct fc_lport *lport = disc->lport;
+
+ FC_DEBUG_DISC("Restarting discovery for port (%6x)\n",
+ fc_host_port_id(lport->host));
+
+ list_for_each_entry_safe(rdata, next, &disc->rports, peers) {
+ rport = PRIV_TO_RPORT(rdata);
+ FC_DEBUG_DISC("list_del(%6x)\n", rport->port_id);
+ list_del(&rdata->peers);
+ lport->tt.rport_logoff(rport);
+ }
+
+ disc->requested = 1;
+ if (!disc->pending)
+ fc_disc_gpn_ft_req(disc);
+}
+
+/**
+ * fc_disc_start - Fibre Channel Target discovery
+ * @lport: FC local port
+ *
+ * Returns non-zero if discovery cannot be started.
+ */
+static void fc_disc_start(void (*disc_callback)(struct fc_lport *,
+ enum fc_disc_event),
+ struct fc_lport *lport)
+{
+ struct fc_rport *rport;
+ struct fc_rport_identifiers ids;
+ 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;
+
+ /*
+ * If not ready, or already running discovery, just set request flag.
+ */
+ disc->requested = 1;
+
+ if (disc->pending) {
+ mutex_unlock(&disc->disc_mutex);
+ return;
+ }
+
+ /*
+ * Handle point-to-point mode as a simple discovery
+ * of the remote port. Yucky, yucky, yuck, yuck!
+ */
+ rport = disc->lport->ptp_rp;
+ if (rport) {
+ ids.port_id = rport->port_id;
+ ids.port_name = rport->port_name;
+ ids.node_name = rport->node_name;
+ ids.roles = FC_RPORT_ROLE_UNKNOWN;
+ get_device(&rport->dev);
+
+ if (!fc_disc_new_target(disc, rport, &ids)) {
+ disc->event = DISC_EV_SUCCESS;
+ fc_disc_done(disc);
+ }
+ put_device(&rport->dev);
+ } else {
+ fc_disc_gpn_ft_req(disc); /* get ports by FC-4 type */
+ }
+
+ mutex_unlock(&disc->disc_mutex);
+}
+
+static struct fc_rport_operations fc_disc_rport_ops = {
+ .event_callback = fc_disc_rport_callback,
+};
+
+/**
+ * fc_disc_new_target - Handle new target found by discovery
+ * @lport: FC local port
+ * @rport: The previous FC remote port (NULL if new remote port)
+ * @ids: Identifiers for the new FC remote port
+ *
+ * Locking Note: This function expects that the disc_mutex is locked
+ * before it is called.
+ */
+static int fc_disc_new_target(struct fc_disc *disc,
+ struct fc_rport *rport,
+ struct fc_rport_identifiers *ids)
+{
+ struct fc_lport *lport = disc->lport;
+ struct fc_rport_libfc_priv *rp;
+ int error = 0;
+
+ if (rport && ids->port_name) {
+ if (rport->port_name == -1) {
+ /*
+ * Set WWN and fall through to notify of create.
+ */
+ fc_rport_set_name(rport, ids->port_name,
+ rport->node_name);
+ } else if (rport->port_name != ids->port_name) {
+ /*
+ * This is a new port with the same FCID as
+ * a previously-discovered port. Presumably the old
+ * port logged out and a new port logged in and was
+ * assigned the same FCID. This should be rare.
+ * Delete the old one and fall thru to re-create.
+ */
+ fc_disc_del_target(disc, rport);
+ rport = NULL;
+ }
+ }
+ if (((ids->port_name != -1) || (ids->port_id != -1)) &&
+ ids->port_id != fc_host_port_id(lport->host) &&
+ ids->port_name != lport->wwpn) {
+ if (!rport) {
+ rport = lport->tt.rport_lookup(lport, ids->port_id);
+ if (!rport) {
+ struct fc_disc_port dp;
+ dp.lp = lport;
+ dp.ids.port_id = ids->port_id;
+ dp.ids.port_name = ids->port_name;
+ dp.ids.node_name = ids->node_name;
+ dp.ids.roles = ids->roles;
+ rport = fc_rport_rogue_create(&dp);
+ }
+ if (!rport)
+ error = -ENOMEM;
+ }
+ if (rport) {
+ rp = rport->dd_data;
+ rp->ops = &fc_disc_rport_ops;
+ rp->rp_state = RPORT_ST_INIT;
+ lport->tt.rport_login(rport);
+ }
+ }
+ return error;
+}
+
+/**
+ * fc_disc_del_target - Delete a target
+ * @disc: FC discovery context
+ * @rport: The remote port to be removed
+ */
+static void fc_disc_del_target(struct fc_disc *disc, struct fc_rport *rport)
+{
+ struct fc_lport *lport = disc->lport;
+ struct fc_rport_libfc_priv *rdata = RPORT_TO_PRIV(rport);
+ list_del(&rdata->peers);
+ lport->tt.rport_logoff(rport);
+}
+
+/**
+ * fc_disc_done - Discovery has been completed
+ * @disc: FC discovery context
+ */
+static void fc_disc_done(struct fc_disc *disc)
+{
+ struct fc_lport *lport = disc->lport;
+
+ FC_DEBUG_DISC("Discovery complete for port (%6x)\n",
+ fc_host_port_id(lport->host));
+
+ disc->disc_callback(lport, disc->event);
+ disc->event = DISC_EV_NONE;
+
+ if (disc->requested)
+ fc_disc_gpn_ft_req(disc);
+ else
+ disc->pending = 0;
+}
+
+/**
+ * fc_disc_error - Handle error on dNS request
+ * @disc: FC discovery context
+ * @fp: The frame pointer
+ */
+static void fc_disc_error(struct fc_disc *disc, struct fc_frame *fp)
+{
+ struct fc_lport *lport = disc->lport;
+ unsigned long delay = 0;
+ if (fc_disc_debug)
+ FC_DBG("Error %ld, retries %d/%d\n",
+ PTR_ERR(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 {
+ /* exceeded retries */
+ disc->event = DISC_EV_FAILED;
+ fc_disc_done(disc);
+ }
+ }
+}
+
+/**
+ * fc_disc_gpn_ft_req - Send Get Port Names by FC-4 type (GPN_FT) request
+ * @lport: FC discovery context
+ *
+ * Locking Note: This function expects that the disc_mutex is locked
+ * before it is called.
+ */
+static void fc_disc_gpn_ft_req(struct fc_disc *disc)
+{
+ struct fc_frame *fp;
+ struct fc_lport *lport = disc->lport;
+
+ 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, NULL, fp,
+ FC_NS_GPN_FT,
+ fc_disc_gpn_ft_resp,
+ disc, lport->e_d_tov))
+ return;
+err:
+ fc_disc_error(disc, fp);
+}
+
+/**
+ * fc_disc_gpn_ft_parse - Parse the list of IDs and names resulting from a request
+ * @lport: Fibre Channel host port instance
+ * @buf: GPN_FT response buffer
+ * @len: size of response buffer
+ */
+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_disc_port dp;
+ struct fc_rport *rport;
+ struct fc_rport_libfc_priv *rdata;
+
+ lport = disc->lport;
+
+ /*
+ * Handle partial name record left over from previous call.
+ */
+ bp = buf;
+ plen = len;
+ np = (struct fc_gpn_ft_resp *)bp;
+ tlen = disc->buf_len;
+ 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)) {
+ dp.lp = lport;
+ dp.ids.port_id = ntoh24(np->fp_fid);
+ dp.ids.port_name = ntohll(np->fp_wwpn);
+ dp.ids.node_name = -1;
+ dp.ids.roles = FC_RPORT_ROLE_UNKNOWN;
+
+ if ((dp.ids.port_id != fc_host_port_id(lport->host)) &&
+ (dp.ids.port_name != lport->wwpn)) {
+ rport = fc_rport_rogue_create(&dp);
+ if (rport) {
+ rdata = rport->dd_data;
+ rdata->ops = &fc_disc_rport_ops;
+ rdata->local_port = lport;
+ lport->tt.rport_login(rport);
+ } else
+ FC_DBG("Failed to allocate memory for "
+ "the newly discovered port (%6x)\n",
+ dp.ids.port_id);
+ }
+
+ if (np->fp_flags & FC_NS_FID_LAST) {
+ disc->event = DISC_EV_SUCCESS;
+ fc_disc_done(disc);
+ 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_DEBUG_DISC("Partial buffer remains "
+ "for discovery by (%6x)\n",
+ fc_host_port_id(lport->host));
+ memcpy(&disc->partial_buf, np, len);
+ }
+ disc->buf_len = (unsigned char) len;
+ } else {
+ disc->buf_len = 0;
+ }
+ return error;
+}
+
+/*
+ * Handle retry of memory allocation for remote ports.
+ */
+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);
+ if (disc->requested && !disc->pending)
+ 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: Current sequence of GPN_FT exchange
+ * @fp: response frame
+ * @lp_arg: Fibre Channel host port instance
+ *
+ * Locking Note: This function expects that the disc_mutex is locked
+ * before it is called.
+ */
+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;
+ unsigned int seq_cnt;
+ void *buf = NULL;
+ unsigned int len;
+ int error;
+
+ FC_DEBUG_DISC("Received a GPN_FT response on port (%6x)\n",
+ fc_host_port_id(disc->lport->host));
+
+ if (IS_ERR(fp)) {
+ fc_disc_error(disc, fp);
+ 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_DBG("GPN_FT response too short, len %d\n",
+ fr_len(fp));
+ } else if (ntohs(cp->ct_cmd) == FC_FS_ACC) {
+
+ /*
+ * Accepted. Parse response.
+ */
+ buf = cp + 1;
+ len -= sizeof(*cp);
+ } else if (ntohs(cp->ct_cmd) == FC_FS_RJT) {
+ FC_DBG("GPN_FT rejected reason %x exp %x "
+ "(check zoning)\n", cp->ct_reason,
+ cp->ct_explan);
+ disc->event = DISC_EV_FAILED;
+ fc_disc_done(disc);
+ } else {
+ FC_DBG("GPN_FT unexpected response code %x\n",
+ ntohs(cp->ct_cmd));
+ }
+ } else if (fr_sof(fp) == FC_SOF_N3 &&
+ seq_cnt == disc->seq_count) {
+ buf = fh + 1;
+ } else {
+ FC_DBG("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));
+ }
+ if (buf) {
+ error = fc_disc_gpn_ft_parse(disc, buf, len);
+ if (error)
+ fc_disc_error(disc, fp);
+ else
+ disc->seq_count++;
+ }
+ fc_frame_free(fp);
+}
+
+/**
+ * fc_disc_single - Discover the directory information for a single target
+ * @lport: FC local port
+ * @dp: The port to rediscover
+ *
+ * Locking Note: This function expects that the disc_mutex is locked
+ * before it is called.
+ */
+static void fc_disc_single(struct fc_disc *disc, struct fc_disc_port *dp)
+{
+ struct fc_lport *lport;
+ struct fc_rport *rport;
+ struct fc_rport *new_rport;
+ struct fc_rport_libfc_priv *rdata;
+
+ lport = disc->lport;
+
+ if (dp->ids.port_id == fc_host_port_id(lport->host))
+ goto out;
+
+ rport = lport->tt.rport_lookup(lport, dp->ids.port_id);
+ if (rport)
+ fc_disc_del_target(disc, rport);
+
+ new_rport = fc_rport_rogue_create(dp);
+ if (new_rport) {
+ rdata = new_rport->dd_data;
+ rdata->ops = &fc_disc_rport_ops;
+ kfree(dp);
+ lport->tt.rport_login(new_rport);
+ }
+ return;
+out:
+ kfree(dp);
+}
+
+/**
+ * fc_disc_stop - Stop discovery for a given lport
+ * @lport: The lport that discovery should stop for
+ */
+void fc_disc_stop(struct fc_lport *lport)
+{
+ struct fc_disc *disc = &lport->disc;
+
+ if (disc) {
+ cancel_delayed_work_sync(&disc->disc_work);
+ fc_disc_stop_rports(disc);
+ }
+}
+
+/**
+ * fc_disc_stop_final - Stop discovery for a given lport
+ * @lport: The lport that discovery should stop for
+ *
+ * This function will block until discovery has been
+ * completely stopped and all rports have been deleted.
+ */
+void fc_disc_stop_final(struct fc_lport *lport)
+{
+ fc_disc_stop(lport);
+ lport->tt.rport_flush_queue();
+}
+
+/**
+ * fc_disc_init - Initialize the discovery block
+ * @lport: FC local port
+ */
+int fc_disc_init(struct fc_lport *lport)
+{
+ 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;
+
+ if (!lport->tt.rport_lookup)
+ lport->tt.rport_lookup = fc_disc_lookup_rport;
+
+ disc = &lport->disc;
+ INIT_DELAYED_WORK(&disc->disc_work, fc_disc_timeout);
+ mutex_init(&disc->disc_mutex);
+ INIT_LIST_HEAD(&disc->rports);
+
+ disc->lport = lport;
+ disc->delay = FC_DISC_DELAY;
+ disc->event = DISC_EV_NONE;
+
+ return 0;
+}
+EXPORT_SYMBOL(fc_disc_init);