[SCSI] qla4xxx: multi-session fix for flash ddbs

Allow multi-session to target (for flash ddbs) accesible via
multiple network portal

Signed-off-by: Vikas Chaudhary <vikas.chaudhary@qlogic.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

2 files changed, 144 insertions, 13 deletions

diff --git a/drivers/scsi/qla4xxx/ql4_def.h b/drivers/scsi/qla4xxx/ql4_def.h
index 96a5616a8fda..7fdba7f1ffb7 100644
--- a/drivers/scsi/qla4xxx/ql4_def.h
+++ b/drivers/scsi/qla4xxx/ql4_def.h
@@ -279,6 +279,7 @@ struct qla_ddb_index {
         struct list_head list;
         uint16_t fw_ddb_idx;
         struct dev_db_entry fw_ddb;
+        uint8_t flash_isid[6];
 };
 
 #define DDB_IPADDR_LEN 64
diff --git a/drivers/scsi/qla4xxx/ql4_os.c b/drivers/scsi/qla4xxx/ql4_os.c
index cd15678f9ada..9da426628b97 100644
--- a/drivers/scsi/qla4xxx/ql4_os.c
+++ b/drivers/scsi/qla4xxx/ql4_os.c
@@ -4299,7 +4299,8 @@ static void qla4xxx_get_param_ddb(struct ddb_entry *ddb_entry,
 }
 
 static void qla4xxx_convert_param_ddb(struct dev_db_entry *fw_ddb_entry,
-                                      struct ql4_tuple_ddb *tddb)
+                                      struct ql4_tuple_ddb *tddb,
+                                      uint8_t *flash_isid)
 {
         uint16_t options = 0;
 
@@ -4314,7 +4315,12 @@ static void qla4xxx_convert_param_ddb(struct dev_db_entry *fw_ddb_entry,
                 sprintf(tddb->ip_addr, "%pI4", fw_ddb_entry->ip_addr);
 
         tddb->port = le16_to_cpu(fw_ddb_entry->port);
-        memcpy(&tddb->isid[0], &fw_ddb_entry->isid[0], sizeof(tddb->isid));
+
+        if (flash_isid == NULL)
+                memcpy(&tddb->isid[0], &fw_ddb_entry->isid[0],
+                       sizeof(tddb->isid));
+        else
+                memcpy(&tddb->isid[0], &flash_isid[0], sizeof(tddb->isid));
 }
 
 static int qla4xxx_compare_tuple_ddb(struct scsi_qla_host *ha,
@@ -4385,7 +4391,7 @@ static int qla4xxx_is_session_exists(struct scsi_qla_host *ha,
                 goto exit_check;
         }
 
-        qla4xxx_convert_param_ddb(fw_ddb_entry, fw_tddb);
+        qla4xxx_convert_param_ddb(fw_ddb_entry, fw_tddb, NULL);
 
         for (idx = 0; idx < MAX_DDB_ENTRIES; idx++) {
                 ddb_entry = qla4xxx_lookup_ddb_by_fw_index(ha, idx);
@@ -4407,6 +4413,102 @@ exit_check:
         return ret;
 }
 
+/**
+ * qla4xxx_check_existing_isid - check if target with same isid exist
+ *                               in target list
+ * @list_nt: list of target
+ * @isid: isid to check
+ *
+ * This routine return QLA_SUCCESS if target with same isid exist
+ **/
+static int qla4xxx_check_existing_isid(struct list_head *list_nt, uint8_t *isid)
+{
+        struct qla_ddb_index *nt_ddb_idx, *nt_ddb_idx_tmp;
+        struct dev_db_entry *fw_ddb_entry;
+
+        list_for_each_entry_safe(nt_ddb_idx, nt_ddb_idx_tmp, list_nt, list) {
+                fw_ddb_entry = &nt_ddb_idx->fw_ddb;
+
+                if (memcmp(&fw_ddb_entry->isid[0], &isid[0],
+                           sizeof(nt_ddb_idx->fw_ddb.isid)) == 0) {
+                        return QLA_SUCCESS;
+                }
+        }
+        return QLA_ERROR;
+}
+
+/**
+ * qla4xxx_update_isid - compare ddbs and updated isid
+ * @ha: Pointer to host adapter structure.
+ * @list_nt: list of nt target
+ * @fw_ddb_entry: firmware ddb entry
+ *
+ * This routine update isid if ddbs have same iqn, same isid and
+ * different IP addr.
+ * Return QLA_SUCCESS if isid is updated.
+ **/
+static int qla4xxx_update_isid(struct scsi_qla_host *ha,
+                               struct list_head *list_nt,
+                               struct dev_db_entry *fw_ddb_entry)
+{
+        uint8_t base_value, i;
+
+        base_value = fw_ddb_entry->isid[1] & 0x1f;
+        for (i = 0; i < 8; i++) {
+                fw_ddb_entry->isid[1] = (base_value | (i << 5));
+                if (qla4xxx_check_existing_isid(list_nt, fw_ddb_entry->isid))
+                        break;
+        }
+
+        if (!qla4xxx_check_existing_isid(list_nt, fw_ddb_entry->isid))
+                return QLA_ERROR;
+
+        return QLA_SUCCESS;
+}
+
+/**
+ * qla4xxx_should_update_isid - check if isid need to update
+ * @ha: Pointer to host adapter structure.
+ * @old_tddb: ddb tuple
+ * @new_tddb: ddb tuple
+ *
+ * Return QLA_SUCCESS if different IP, different PORT, same iqn,
+ * same isid
+ **/
+static int qla4xxx_should_update_isid(struct scsi_qla_host *ha,
+                                      struct ql4_tuple_ddb *old_tddb,
+                                      struct ql4_tuple_ddb *new_tddb)
+{
+        if (strcmp(old_tddb->ip_addr, new_tddb->ip_addr) == 0) {
+                /* Same ip */
+                if (old_tddb->port == new_tddb->port)
+                        return QLA_ERROR;
+        }
+
+        if (strcmp(old_tddb->iscsi_name, new_tddb->iscsi_name))
+                /* different iqn */
+                return QLA_ERROR;
+
+        if (memcmp(&old_tddb->isid[0], &new_tddb->isid[0],
+                   sizeof(old_tddb->isid)))
+                /* different isid */
+                return QLA_ERROR;
+
+        return QLA_SUCCESS;
+}
+
+/**
+ * qla4xxx_is_flash_ddb_exists - check if fw_ddb_entry already exists in list_nt
+ * @ha: Pointer to host adapter structure.
+ * @list_nt: list of nt target.
+ * @fw_ddb_entry: firmware ddb entry.
+ *
+ * This routine check if fw_ddb_entry already exists in list_nt to avoid
+ * duplicate ddb in list_nt.
+ * Return QLA_SUCCESS if duplicate ddb exit in list_nl.
+ * Note: This function also update isid of DDB if required.
+ **/
+
 static int qla4xxx_is_flash_ddb_exists(struct scsi_qla_host *ha,
                                        struct list_head *list_nt,
                                        struct dev_db_entry *fw_ddb_entry)
@@ -4414,7 +4516,7 @@ static int qla4xxx_is_flash_ddb_exists(struct scsi_qla_host *ha,
         struct qla_ddb_index  *nt_ddb_idx, *nt_ddb_idx_tmp;
         struct ql4_tuple_ddb *fw_tddb = NULL;
         struct ql4_tuple_ddb *tmp_tddb = NULL;
-        int ret = QLA_ERROR;
+        int rval, ret = QLA_ERROR;
 
         fw_tddb = vzalloc(sizeof(*fw_tddb));
         if (!fw_tddb) {
@@ -4432,12 +4534,28 @@ static int qla4xxx_is_flash_ddb_exists(struct scsi_qla_host *ha,
                 goto exit_check;
         }
 
-        qla4xxx_convert_param_ddb(fw_ddb_entry, fw_tddb);
+        qla4xxx_convert_param_ddb(fw_ddb_entry, fw_tddb, NULL);
 
         list_for_each_entry_safe(nt_ddb_idx, nt_ddb_idx_tmp, list_nt, list) {
-                qla4xxx_convert_param_ddb(&nt_ddb_idx->fw_ddb, tmp_tddb);
-                if (!qla4xxx_compare_tuple_ddb(ha, fw_tddb, tmp_tddb, true)) {
-                        ret = QLA_SUCCESS; /* found */
+                qla4xxx_convert_param_ddb(&nt_ddb_idx->fw_ddb, tmp_tddb,
+                                          nt_ddb_idx->flash_isid);
+                ret = qla4xxx_compare_tuple_ddb(ha, fw_tddb, tmp_tddb, true);
+                /* found duplicate ddb */
+                if (ret == QLA_SUCCESS)
+                        goto exit_check;
+        }
+
+        list_for_each_entry_safe(nt_ddb_idx, nt_ddb_idx_tmp, list_nt, list) {
+                qla4xxx_convert_param_ddb(&nt_ddb_idx->fw_ddb, tmp_tddb, NULL);
+
+                ret = qla4xxx_should_update_isid(ha, tmp_tddb, fw_tddb);
+                if (ret == QLA_SUCCESS) {
+                        rval = qla4xxx_update_isid(ha, list_nt, fw_ddb_entry);
+                        if (rval == QLA_SUCCESS)
+                                ret = QLA_ERROR;
+                        else
+                                ret = QLA_SUCCESS;
+
                         goto exit_check;
                 }
         }
@@ -4788,14 +4906,26 @@ static void qla4xxx_build_nt_list(struct scsi_qla_host *ha,
 
                         nt_ddb_idx->fw_ddb_idx = idx;
 
-                        memcpy(&nt_ddb_idx->fw_ddb, fw_ddb_entry,
-                               sizeof(struct dev_db_entry));
-
-                        if (qla4xxx_is_flash_ddb_exists(ha, list_nt,
-                                        fw_ddb_entry) == QLA_SUCCESS) {
+                        /* Copy original isid as it may get updated in function
+                         * qla4xxx_update_isid(). We need original isid in
+                         * function qla4xxx_compare_tuple_ddb to find duplicate
+                         * target */
+                        memcpy(&nt_ddb_idx->flash_isid[0],
+                               &fw_ddb_entry->isid[0],
+                               sizeof(nt_ddb_idx->flash_isid));
+
+                        ret = qla4xxx_is_flash_ddb_exists(ha, list_nt,
+                                                          fw_ddb_entry);
+                        if (ret == QLA_SUCCESS) {
+                                /* free nt_ddb_idx and do not add to list_nt */
                                 vfree(nt_ddb_idx);
                                 goto continue_next_nt;
                         }
+
+                        /* Copy updated isid */
+                        memcpy(&nt_ddb_idx->fw_ddb, fw_ddb_entry,
+                               sizeof(struct dev_db_entry));
+
                         list_add_tail(&nt_ddb_idx->list, list_nt);
                 } else if (is_reset == RESET_ADAPTER) {
                         if (qla4xxx_is_session_exists(ha, fw_ddb_entry) ==