iscsi-target: Make iscsi_tpg_np driver show/store use generic code

Go ahead and fold the duplicate iscsi_tpg_np driver attribute
show/store functions into generic callers, invoked by current
driver specific functions.

This allows for future v4.8+ changes to have iscsi_target_mod
use tpg_np driver attributes at runtime, instead of having
the defaults hardcoded in iscsi_target_configfs.c.

Also, drop the unused/legacy 'sctp' attribute for non standard
RFC-3720 operation with IPPROTO_SCTP.

Cc: Varun Prakash <varun@chelsio.com>
Cc: Hariprasad Shenai <hariprasad@chelsio.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

1 files changed, 41 insertions, 158 deletions

diff --git a/drivers/target/iscsi/iscsi_target_configfs.c b/drivers/target/iscsi/iscsi_target_configfs.c
index 1b8f885dbfeb..33d811ac9539 100644
--- a/drivers/target/iscsi/iscsi_target_configfs.c
+++ b/drivers/target/iscsi/iscsi_target_configfs.c
@@ -43,14 +43,15 @@ static inline struct iscsi_tpg_np *to_iscsi_tpg_np(struct config_item *item)
         return container_of(to_tpg_np(item), struct iscsi_tpg_np, se_tpg_np);
 }
 
-static ssize_t lio_target_np_sctp_show(struct config_item *item, char *page)
+static ssize_t lio_target_np_driver_show(struct config_item *item, char *page,
+                                         enum iscsit_transport_type type)
 {
         struct iscsi_tpg_np *tpg_np = to_iscsi_tpg_np(item);
-        struct iscsi_tpg_np *tpg_np_sctp;
+        struct iscsi_tpg_np *tpg_np_new;
         ssize_t rb;
 
-        tpg_np_sctp = iscsit_tpg_locate_child_np(tpg_np, ISCSI_SCTP_TCP);
-        if (tpg_np_sctp)
+        tpg_np_new = iscsit_tpg_locate_child_np(tpg_np, type);
+        if (tpg_np_new)
                 rb = sprintf(page, "1\n");
         else
                 rb = sprintf(page, "0\n");
@@ -58,86 +59,20 @@ static ssize_t lio_target_np_sctp_show(struct config_item *item, char *page)
         return rb;
 }
 
-static ssize_t lio_target_np_sctp_store(struct config_item *item,
-                const char *page, size_t count)
+static ssize_t lio_target_np_driver_store(struct config_item *item,
+                const char *page, size_t count, enum iscsit_transport_type type,
+                const char *mod_name)
 {
         struct iscsi_tpg_np *tpg_np = to_iscsi_tpg_np(item);
         struct iscsi_np *np;
         struct iscsi_portal_group *tpg;
-        struct iscsi_tpg_np *tpg_np_sctp = NULL;
+        struct iscsi_tpg_np *tpg_np_new = NULL;
         u32 op;
-        int ret;
-
-        ret = kstrtou32(page, 0, &op);
-        if (ret)
-                return ret;
-        if ((op != 1) && (op != 0)) {
-                pr_err("Illegal value for tpg_enable: %u\n", op);
-                return -EINVAL;
-        }
-        np = tpg_np->tpg_np;
-        if (!np) {
-                pr_err("Unable to locate struct iscsi_np from"
-                                " struct iscsi_tpg_np\n");
-                return -EINVAL;
-        }
-
-        tpg = tpg_np->tpg;
-        if (iscsit_get_tpg(tpg) < 0)
-                return -EINVAL;
+        int rc;
 
-        if (op) {
-                /*
-                 * Use existing np->np_sockaddr for SCTP network portal reference
-                 */
-                tpg_np_sctp = iscsit_tpg_add_network_portal(tpg, &np->np_sockaddr,
-                                        tpg_np, ISCSI_SCTP_TCP);
-                if (!tpg_np_sctp || IS_ERR(tpg_np_sctp))
-                        goto out;
-        } else {
-                tpg_np_sctp = iscsit_tpg_locate_child_np(tpg_np, ISCSI_SCTP_TCP);
-                if (!tpg_np_sctp)
-                        goto out;
-
-                ret = iscsit_tpg_del_network_portal(tpg, tpg_np_sctp);
-                if (ret < 0)
-                        goto out;
-        }
-
-        iscsit_put_tpg(tpg);
-        return count;
-out:
-        iscsit_put_tpg(tpg);
-        return -EINVAL;
-}
-
-static ssize_t lio_target_np_iser_show(struct config_item *item, char *page)
-{
-        struct iscsi_tpg_np *tpg_np = to_iscsi_tpg_np(item);
-        struct iscsi_tpg_np *tpg_np_iser;
-        ssize_t rb;
-
-        tpg_np_iser = iscsit_tpg_locate_child_np(tpg_np, ISCSI_INFINIBAND);
-        if (tpg_np_iser)
-                rb = sprintf(page, "1\n");
-        else
-                rb = sprintf(page, "0\n");
-
-        return rb;
-}
-
-static ssize_t lio_target_np_iser_store(struct config_item *item,
-                const char *page, size_t count)
-{
-        struct iscsi_tpg_np *tpg_np = to_iscsi_tpg_np(item);
-        struct iscsi_np *np;
-        struct iscsi_portal_group *tpg;
-        struct iscsi_tpg_np *tpg_np_iser = NULL;
-        char *endptr;
-        u32 op;
-        int rc = 0;
-
-        op = simple_strtoul(page, &endptr, 0);
+        rc = kstrtou32(page, 0, &op);
+        if (rc)
+                return rc;
         if ((op != 1) && (op != 0)) {
                 pr_err("Illegal value for tpg_enable: %u\n", op);
                 return -EINVAL;
@@ -154,22 +89,23 @@ static ssize_t lio_target_np_iser_store(struct config_item *item,
                 return -EINVAL;
 
         if (op) {
-                rc = request_module("ib_isert");
-                if (rc != 0) {
-                        pr_warn("Unable to request_module for ib_isert\n");
-                        rc = 0;
+                if (strlen(mod_name)) {
+                        rc = request_module(mod_name);
+                        if (rc != 0) {
+                                pr_warn("Unable to request_module for %s\n",
+                                        mod_name);
+                                rc = 0;
+                        }
                 }
 
-                tpg_np_iser = iscsit_tpg_add_network_portal(tpg, &np->np_sockaddr,
-                                tpg_np, ISCSI_INFINIBAND);
-                if (IS_ERR(tpg_np_iser)) {
-                        rc = PTR_ERR(tpg_np_iser);
+                tpg_np_new = iscsit_tpg_add_network_portal(tpg,
+                                        &np->np_sockaddr, tpg_np, type);
+                if (IS_ERR(tpg_np_new))
                         goto out;
-                }
         } else {
-                tpg_np_iser = iscsit_tpg_locate_child_np(tpg_np, ISCSI_INFINIBAND);
-                if (tpg_np_iser) {
-                        rc = iscsit_tpg_del_network_portal(tpg, tpg_np_iser);
+                tpg_np_new = iscsit_tpg_locate_child_np(tpg_np, type);
+                if (tpg_np_new) {
+                        rc = iscsit_tpg_del_network_portal(tpg, tpg_np_new);
                         if (rc < 0)
                                 goto out;
                 }
@@ -182,86 +118,33 @@ out:
         return rc;
 }
 
-static ssize_t lio_target_np_hw_offload_show(struct config_item *item,
-                                             char *page)
+static ssize_t lio_target_np_iser_show(struct config_item *item, char *page)
 {
-        struct iscsi_tpg_np *tpg_np = to_iscsi_tpg_np(item);
-        struct iscsi_tpg_np *tpg_np_hw_offload;
-        ssize_t rb;
+        return lio_target_np_driver_show(item, page, ISCSI_INFINIBAND);
+}
 
-        tpg_np_hw_offload = iscsit_tpg_locate_child_np(tpg_np,
-                                                       ISCSI_HW_OFFLOAD);
-        if (tpg_np_hw_offload)
-                rb = sprintf(page, "1\n");
-        else
-                rb = sprintf(page, "0\n");
+static ssize_t lio_target_np_iser_store(struct config_item *item,
+                                        const char *page, size_t count)
+{
+        return lio_target_np_driver_store(item, page, count,
+                                          ISCSI_INFINIBAND, "ib_isert");
+}
+CONFIGFS_ATTR(lio_target_np_, iser);
 
-        return rb;
+static ssize_t lio_target_np_hw_offload_show(struct config_item *item, char *page)
+{
+        return lio_target_np_driver_show(item, page, ISCSI_HW_OFFLOAD);
 }
 
 static ssize_t lio_target_np_hw_offload_store(struct config_item *item,
                                               const char *page, size_t count)
 {
-        struct iscsi_tpg_np *tpg_np = to_iscsi_tpg_np(item);
-        struct iscsi_np *np;
-        struct iscsi_portal_group *tpg;
-        struct iscsi_tpg_np *tpg_np_hw_offload = NULL;
-        u32 op;
-        int rc = 0;
-
-        rc = kstrtou32(page, 0, &op);
-        if (rc)
-                return rc;
-
-        if ((op != 1) && (op != 0)) {
-                pr_err("Illegal value for tpg_enable: %u\n", op);
-                return -EINVAL;
-        }
-
-        np = tpg_np->tpg_np;
-        if (!np) {
-                pr_err("Unable to locate struct iscsi_np from"
-                       " struct iscsi_tpg_np\n");
-                return -EINVAL;
-        }
-
-        tpg = tpg_np->tpg;
-        if (iscsit_get_tpg(tpg) < 0)
-                return -EINVAL;
-
-        if (op) {
-                tpg_np_hw_offload = iscsit_tpg_add_network_portal(tpg,
-                                &np->np_sockaddr, tpg_np, ISCSI_HW_OFFLOAD);
-
-                if (IS_ERR(tpg_np_hw_offload)) {
-                        rc = PTR_ERR(tpg_np_hw_offload);
-                        goto out;
-                }
-        } else {
-                tpg_np_hw_offload = iscsit_tpg_locate_child_np(tpg_np,
-                                ISCSI_HW_OFFLOAD);
-
-                if (tpg_np_hw_offload) {
-                        rc = iscsit_tpg_del_network_portal(tpg,
-                                                           tpg_np_hw_offload);
-                        if (rc < 0)
-                                goto out;
-                }
-        }
-
-        iscsit_put_tpg(tpg);
-        return count;
-out:
-        iscsit_put_tpg(tpg);
-        return rc;
+        return lio_target_np_driver_store(item, page, count,
+                                          ISCSI_HW_OFFLOAD, "");
 }
-
-CONFIGFS_ATTR(lio_target_np_, sctp);
-CONFIGFS_ATTR(lio_target_np_, iser);
 CONFIGFS_ATTR(lio_target_np_, hw_offload);
 
 static struct configfs_attribute *lio_target_portal_attrs[] = {
-        &lio_target_np_attr_sctp,
         &lio_target_np_attr_iser,
         &lio_target_np_attr_hw_offload,
         NULL,