UBI: fix and cleanup volume opening functions

This patch fixes error codes of the functions - if the device number
is out of range, -EINVAL should be returned. It also removes unneeded
try_module_get call from the open by name function.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>

diff --git a/drivers/mtd/ubi/kapi.c b/drivers/mtd/ubi/kapi.c
index 96f5fef..9c28376 100644 (file)
--- a/drivers/mtd/ubi/kapi.c
+++ b/drivers/mtd/ubi/kapi.c
@@ -104,37 +104,32 @@ struct ubi_volume_desc *ubi_open_volume(int ubi_num, int vol_id, int mode)
 
        dbg_msg("open device %d volume %d, mode %d", ubi_num, vol_id, mode);
 
-       err = -ENODEV;
-       if (ubi_num < 0)
-               return ERR_PTR(err);
-
-       ubi = ubi_devices[ubi_num];
+       if (ubi_num < 0 || ubi_num >= UBI_MAX_DEVICES)
+               return ERR_PTR(-EINVAL);
 
-       if (!try_module_get(THIS_MODULE))
-               return ERR_PTR(err);
+       if (mode != UBI_READONLY && mode != UBI_READWRITE &&
+           mode != UBI_EXCLUSIVE)
+               return ERR_PTR(-EINVAL);
 
-       if (ubi_num >= UBI_MAX_DEVICES || !ubi)
-               goto out_put;
+       ubi = ubi_devices[ubi_num];
+       if (!ubi)
+               return ERR_PTR(-ENODEV);
 
-       err = -EINVAL;
        if (vol_id < 0 || vol_id >= ubi->vtbl_slots)
-               goto out_put;
-       if (mode != UBI_READONLY && mode != UBI_READWRITE &&
-           mode != UBI_EXCLUSIVE)
-               goto out_put;
+               return ERR_PTR(-EINVAL);
 
        desc = kmalloc(sizeof(struct ubi_volume_desc), GFP_KERNEL);
-       if (!desc) {
-               err = -ENOMEM;
-               goto out_put;
-       }
+       if (!desc)
+               return ERR_PTR(-ENOMEM);
+
+       err = -ENODEV;
+       if (!try_module_get(THIS_MODULE))
+               goto out_free;
 
        spin_lock(&ubi->volumes_lock);
        vol = ubi->volumes[vol_id];
-       if (!vol) {
-               err = -ENODEV;
+       if (!vol)
                goto out_unlock;
-       }
 
        err = -EBUSY;
        switch (mode) {
@@ -184,13 +179,14 @@ struct ubi_volume_desc *ubi_open_volume(int ubi_num, int vol_id, int mode)
                vol->checked = 1;
        }
        mutex_unlock(&ubi->volumes_mutex);
+
        return desc;
 
 out_unlock:
        spin_unlock(&ubi->volumes_lock);
-       kfree(desc);
-out_put:
        module_put(THIS_MODULE);
+out_free:
+       kfree(desc);
        return ERR_PTR(err);
 }
 EXPORT_SYMBOL_GPL(ubi_open_volume);
@@ -207,7 +203,6 @@ struct ubi_volume_desc *ubi_open_volume_nm(int ubi_num, const char *name,
                                           int mode)
 {
        int i, vol_id = -1, len;
-       struct ubi_volume_desc *ret;
        struct ubi_device *ubi;
 
        dbg_msg("open volume %s, mode %d", name, mode);
@@ -219,14 +214,12 @@ struct ubi_volume_desc *ubi_open_volume_nm(int ubi_num, const char *name,
        if (len > UBI_VOL_NAME_MAX)
                return ERR_PTR(-EINVAL);
 
-       ret = ERR_PTR(-ENODEV);
-       if (!try_module_get(THIS_MODULE))
-               return ret;
-
-       if (ubi_num < 0 || ubi_num >= UBI_MAX_DEVICES || !ubi_devices[ubi_num])
-               goto out_put;
+       if (ubi_num < 0 || ubi_num >= UBI_MAX_DEVICES)
+               return ERR_PTR(-EINVAL);
 
        ubi = ubi_devices[ubi_num];
+       if (!ubi)
+               return ERR_PTR(-ENODEV);
 
        spin_lock(&ubi->volumes_lock);
        /* Walk all volumes of this UBI device */
@@ -241,13 +234,9 @@ struct ubi_volume_desc *ubi_open_volume_nm(int ubi_num, const char *name,
        spin_unlock(&ubi->volumes_lock);
 
        if (vol_id < 0)
-               goto out_put;
-
-       ret = ubi_open_volume(ubi_num, vol_id, mode);
+               return ERR_PTR(-ENODEV);
 
-out_put:
-       module_put(THIS_MODULE);
-       return ret;
+       return ubi_open_volume(ubi_num, vol_id, mode);
 }
 EXPORT_SYMBOL_GPL(ubi_open_volume_nm);