[SCSI] iscsi class, qla4xxx: fix sess/conn refcounting when find fns are used

This fixes a bug where the iscsi class/driver did not do a put_device
when a sess/conn device was found. This also simplifies the interface
by not having to pass in some arguments that were duplicated and did
not need to be exported.

Reported-by: Zhao Hongjiang <zhaohongjiang@huawei.com>
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Acked-by: Vikas Chaudhary <vikas.chaudhary@qlogic.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

2 files changed, 47 insertions, 49 deletions

diff --git a/drivers/scsi/qla4xxx/ql4_os.c b/drivers/scsi/qla4xxx/ql4_os.c
index d777332dbed8..4d231c12463e 100644
--- a/drivers/scsi/qla4xxx/ql4_os.c
+++ b/drivers/scsi/qla4xxx/ql4_os.c
@@ -5605,6 +5605,7 @@ static int qla4xxx_sysfs_ddb_add(struct Scsi_Host *shost, const char *buf,
                 ql4_printk(KERN_ERR, ha,
                            "%s: A non-persistent entry %s found\n",
                            __func__, dev->kobj.name);
+                put_device(dev);
                 goto exit_ddb_add;
         }
 
@@ -6112,8 +6113,7 @@ qla4xxx_sysfs_ddb_get_param(struct iscsi_bus_flash_session *fnode_sess,
         int parent_type, parent_index = 0xffff;
         int rc = 0;
 
-        dev = iscsi_find_flashnode_conn(fnode_sess, NULL,
-                                        iscsi_is_flashnode_conn_dev);
+        dev = iscsi_find_flashnode_conn(fnode_sess);
         if (!dev)
                 return -EIO;
 
@@ -6347,6 +6347,8 @@ qla4xxx_sysfs_ddb_get_param(struct iscsi_bus_flash_session *fnode_sess,
                 rc = -ENOSYS;
                 break;
         }
+
+        put_device(dev);
         return rc;
 }
 
diff --git a/drivers/scsi/scsi_transport_iscsi.c b/drivers/scsi/scsi_transport_iscsi.c
index 475265a51a51..133926b1bb78 100644
--- a/drivers/scsi/scsi_transport_iscsi.c
+++ b/drivers/scsi/scsi_transport_iscsi.c
@@ -1019,8 +1019,7 @@ exit_match_index:
 /**
  * iscsi_get_flashnode_by_index -finds flashnode session entry by index
  * @shost: pointer to host data
- * @data: pointer to data containing value to use for comparison
- * @fn: function pointer that does actual comparison
+ * @idx: index to match
  *
  * Finds the flashnode session object for the passed index
  *
@@ -1029,13 +1028,13 @@ exit_match_index:
  *  %NULL on failure
  */
 static struct iscsi_bus_flash_session *
-iscsi_get_flashnode_by_index(struct Scsi_Host *shost, void *data,
-                             int (*fn)(struct device *dev, void *data))
+iscsi_get_flashnode_by_index(struct Scsi_Host *shost, uint32_t idx)
 {
         struct iscsi_bus_flash_session *fnode_sess = NULL;
         struct device *dev;
 
-        dev = device_find_child(&shost->shost_gendev, data, fn);
+        dev = device_find_child(&shost->shost_gendev, &idx,
+                                flashnode_match_index);
         if (dev)
                 fnode_sess = iscsi_dev_to_flash_session(dev);
 
@@ -1059,18 +1058,13 @@ struct device *
 iscsi_find_flashnode_sess(struct Scsi_Host *shost, void *data,
                           int (*fn)(struct device *dev, void *data))
 {
-        struct device *dev;
-
-        dev = device_find_child(&shost->shost_gendev, data, fn);
-        return dev;
+        return device_find_child(&shost->shost_gendev, data, fn);
 }
 EXPORT_SYMBOL_GPL(iscsi_find_flashnode_sess);
 
 /**
  * iscsi_find_flashnode_conn - finds flashnode connection entry
  * @fnode_sess: pointer to parent flashnode session entry
- * @data: pointer to data containing value to use for comparison
- * @fn: function pointer that does actual comparison
  *
  * Finds the flashnode connection object comparing the data passed using logic
  * defined in passed function pointer
@@ -1080,14 +1074,10 @@ EXPORT_SYMBOL_GPL(iscsi_find_flashnode_sess);
  *  %NULL on failure
  */
 struct device *
-iscsi_find_flashnode_conn(struct iscsi_bus_flash_session *fnode_sess,
-                          void *data,
-                          int (*fn)(struct device *dev, void *data))
+iscsi_find_flashnode_conn(struct iscsi_bus_flash_session *fnode_sess)
 {
-        struct device *dev;
-
-        dev = device_find_child(&fnode_sess->dev, data, fn);
-        return dev;
+        return device_find_child(&fnode_sess->dev, NULL,
+                                 iscsi_is_flashnode_conn_dev);
 }
 EXPORT_SYMBOL_GPL(iscsi_find_flashnode_conn);
 
@@ -2808,7 +2798,7 @@ static int iscsi_set_flashnode_param(struct iscsi_transport *transport,
         struct iscsi_bus_flash_session *fnode_sess;
         struct iscsi_bus_flash_conn *fnode_conn;
         struct device *dev;
-        uint32_t *idx;
+        uint32_t idx;
         int err = 0;
 
         if (!transport->set_flashnode_param) {
@@ -2824,25 +2814,27 @@ static int iscsi_set_flashnode_param(struct iscsi_transport *transport,
                 goto put_host;
         }
 
-        idx = &ev->u.set_flashnode.flashnode_idx;
-        fnode_sess = iscsi_get_flashnode_by_index(shost, idx,
-                                                  flashnode_match_index);
+        idx = ev->u.set_flashnode.flashnode_idx;
+        fnode_sess = iscsi_get_flashnode_by_index(shost, idx);
         if (!fnode_sess) {
                 pr_err("%s could not find flashnode %u for host no %u\n",
-                       __func__, *idx, ev->u.set_flashnode.host_no);
+                       __func__, idx, ev->u.set_flashnode.host_no);
                 err = -ENODEV;
                 goto put_host;
         }
 
-        dev = iscsi_find_flashnode_conn(fnode_sess, NULL,
-                                        iscsi_is_flashnode_conn_dev);
+        dev = iscsi_find_flashnode_conn(fnode_sess);
         if (!dev) {
                 err = -ENODEV;
-                goto put_host;
+                goto put_sess;
         }
 
         fnode_conn = iscsi_dev_to_flash_conn(dev);
         err = transport->set_flashnode_param(fnode_sess, fnode_conn, data, len);
+        put_device(dev);
+
+put_sess:
+        put_device(&fnode_sess->dev);
 
 put_host:
         scsi_host_put(shost);
@@ -2891,7 +2883,7 @@ static int iscsi_del_flashnode(struct iscsi_transport *transport,
 {
         struct Scsi_Host *shost;
         struct iscsi_bus_flash_session *fnode_sess;
-        uint32_t *idx;
+        uint32_t idx;
         int err = 0;
 
         if (!transport->del_flashnode) {
@@ -2907,17 +2899,17 @@ static int iscsi_del_flashnode(struct iscsi_transport *transport,
                 goto put_host;
         }
 
-        idx = &ev->u.del_flashnode.flashnode_idx;
-        fnode_sess = iscsi_get_flashnode_by_index(shost, idx,
-                                                  flashnode_match_index);
+        idx = ev->u.del_flashnode.flashnode_idx;
+        fnode_sess = iscsi_get_flashnode_by_index(shost, idx);
         if (!fnode_sess) {
                 pr_err("%s could not find flashnode %u for host no %u\n",
-                       __func__, *idx, ev->u.del_flashnode.host_no);
+                       __func__, idx, ev->u.del_flashnode.host_no);
                 err = -ENODEV;
                 goto put_host;
         }
 
         err = transport->del_flashnode(fnode_sess);
+        put_device(&fnode_sess->dev);
 
 put_host:
         scsi_host_put(shost);
@@ -2933,7 +2925,7 @@ static int iscsi_login_flashnode(struct iscsi_transport *transport,
         struct iscsi_bus_flash_session *fnode_sess;
         struct iscsi_bus_flash_conn *fnode_conn;
         struct device *dev;
-        uint32_t *idx;
+        uint32_t idx;
         int err = 0;
 
         if (!transport->login_flashnode) {
@@ -2949,25 +2941,27 @@ static int iscsi_login_flashnode(struct iscsi_transport *transport,
                 goto put_host;
         }
 
-        idx = &ev->u.login_flashnode.flashnode_idx;
-        fnode_sess = iscsi_get_flashnode_by_index(shost, idx,
-                                                  flashnode_match_index);
+        idx = ev->u.login_flashnode.flashnode_idx;
+        fnode_sess = iscsi_get_flashnode_by_index(shost, idx);
         if (!fnode_sess) {
                 pr_err("%s could not find flashnode %u for host no %u\n",
-                       __func__, *idx, ev->u.login_flashnode.host_no);
+                       __func__, idx, ev->u.login_flashnode.host_no);
                 err = -ENODEV;
                 goto put_host;
         }
 
-        dev = iscsi_find_flashnode_conn(fnode_sess, NULL,
-                                        iscsi_is_flashnode_conn_dev);
+        dev = iscsi_find_flashnode_conn(fnode_sess);
         if (!dev) {
                 err = -ENODEV;
-                goto put_host;
+                goto put_sess;
         }
 
         fnode_conn = iscsi_dev_to_flash_conn(dev);
         err = transport->login_flashnode(fnode_sess, fnode_conn);
+        put_device(dev);
+
+put_sess:
+        put_device(&fnode_sess->dev);
 
 put_host:
         scsi_host_put(shost);
@@ -2983,7 +2977,7 @@ static int iscsi_logout_flashnode(struct iscsi_transport *transport,
         struct iscsi_bus_flash_session *fnode_sess;
         struct iscsi_bus_flash_conn *fnode_conn;
         struct device *dev;
-        uint32_t *idx;
+        uint32_t idx;
         int err = 0;
 
         if (!transport->logout_flashnode) {
@@ -2999,26 +2993,28 @@ static int iscsi_logout_flashnode(struct iscsi_transport *transport,
                 goto put_host;
         }
 
-        idx = &ev->u.logout_flashnode.flashnode_idx;
-        fnode_sess = iscsi_get_flashnode_by_index(shost, idx,
-                                                  flashnode_match_index);
+        idx = ev->u.logout_flashnode.flashnode_idx;
+        fnode_sess = iscsi_get_flashnode_by_index(shost, idx);
         if (!fnode_sess) {
                 pr_err("%s could not find flashnode %u for host no %u\n",
-                       __func__, *idx, ev->u.logout_flashnode.host_no);
+                       __func__, idx, ev->u.logout_flashnode.host_no);
                 err = -ENODEV;
                 goto put_host;
         }
 
-        dev = iscsi_find_flashnode_conn(fnode_sess, NULL,
-                                        iscsi_is_flashnode_conn_dev);
+        dev = iscsi_find_flashnode_conn(fnode_sess);
         if (!dev) {
                 err = -ENODEV;
-                goto put_host;
+                goto put_sess;
         }
 
         fnode_conn = iscsi_dev_to_flash_conn(dev);
 
         err = transport->logout_flashnode(fnode_sess, fnode_conn);
+        put_device(dev);
+
+put_sess:
+        put_device(&fnode_sess->dev);
 
 put_host:
         scsi_host_put(shost);