mtd: concat: replace alloc + calloc with 1 alloc

A flex array can be used to reduce the allocation to 1.

And actually mtdconcat was using the pointer + 1 trick to point to the
overallocated area. Better alternatives exist.

Signed-off-by: Rosen Penev <rosenp@gmail.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

diff --git a/drivers/mtd/mtd_virt_concat.c b/drivers/mtd/mtd_virt_concat.c
index 72689545e48effae5fc630a0739dbaca28895a18..37075ead0f3377b601c616400496f26f0521917d 100644 (file)
--- a/drivers/mtd/mtd_virt_concat.c
+++ b/drivers/mtd/mtd_virt_concat.c
@@ -182,18 +182,12 @@ static int mtd_virt_concat_create_item(struct device_node *parts,
        for (i = 1; i < count; i++)
                item->nodes[i] = of_parse_phandle(parts, CONCAT_PROP, (i - 1));
 
-       concat = kzalloc(sizeof(*concat), GFP_KERNEL);
+       concat = kzalloc_flex(*concat, subdev, count, GFP_KERNEL);
        if (!concat) {
                kfree(item);
                return -ENOMEM;
        }
 
-       concat->subdev = kcalloc(count, sizeof(*concat->subdev), GFP_KERNEL);
-       if (!concat->subdev) {
-               kfree(item);
-               kfree(concat);
-               return -ENOMEM;
-       }
        item->concat = concat;
 
        list_add_tail(&item->head, &concat_node_list);

diff --git a/drivers/mtd/mtdconcat.c b/drivers/mtd/mtdconcat.c
index 241d15235d0101fce40fc64a054717c1721d3e97..c97167d51fe2d8a5d101603ecb2307d2a504bbd1 100644 (file)
--- a/drivers/mtd/mtdconcat.c
+++ b/drivers/mtd/mtdconcat.c
@@ -627,7 +627,6 @@ struct mtd_info *mtd_concat_create(struct mtd_info *subdev[],       /* subdevices to c
                                   const char *name)
 {                              /* name for the new device   */
        int i;
-       size_t size;
        struct mtd_concat *concat;
        struct mtd_info *subdev_master = NULL;
        uint32_t max_erasesize, curr_erasesize;
@@ -640,15 +639,13 @@ struct mtd_info *mtd_concat_create(struct mtd_info *subdev[],     /* subdevices to c
        printk(KERN_NOTICE "into device \"%s\"\n", name);
 
        /* allocate the device structure */
-       size = SIZEOF_STRUCT_MTD_CONCAT(num_devs);
-       concat = kzalloc(size, GFP_KERNEL);
+       concat = kzalloc_flex(*concat, subdev, num_devs, GFP_KERNEL);
        if (!concat) {
                printk
                    ("memory allocation error while creating concatenated device \"%s\"\n",
                     name);
                return NULL;
        }
-       concat->subdev = (struct mtd_info **) (concat + 1);
 
        /*
         * Set up the new "super" device's MTD object structure, check for

diff --git a/include/linux/mtd/concat.h b/include/linux/mtd/concat.h
index 2cd9d48958a8cdc34519692e161351295517efb2..f8d4d6ac1fc1dc11b40e0eb29f1fa04212f86e99 100644 (file)
--- a/include/linux/mtd/concat.h
+++ b/include/linux/mtd/concat.h
@@ -18,7 +18,7 @@
 struct mtd_concat {
        struct mtd_info mtd;
        int num_subdev;
-       struct mtd_info **subdev;
+       struct mtd_info *subdev[];
 };
 
 struct mtd_info *mtd_concat_create(