mtd: part: Remove partition overlap checks

This patch makes MTD dynamic partitioning more flexible by removing
overlap checks for dynamic partitions. I don't see any  particular
reason why overlapping dynamic partitions should be prohibited while
static partitions are allowed to overlap freely.

The checks previously had an off-by-one error, where 'end' should be
one less than what it is currently set at, and adding partitions out of
increasing order will fail. Disabling the checks resolves this issue.

Signed-off-by: Dan Ehrenberg <dehrenberg@chromium.org>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>

diff --git a/drivers/mtd/mtdpart.c b/drivers/mtd/mtdpart.c
index be803408670154955a7bcb8ae59a1d17ef93548e..cafdb8855a794f93f2adf56ca917fcb7a283e9df 100644 (file)
--- a/drivers/mtd/mtdpart.c
+++ b/drivers/mtd/mtdpart.c
@@ -582,8 +582,7 @@ int mtd_add_partition(struct mtd_info *master, const char *name,
                      long long offset, long long length)
 {
        struct mtd_partition part;
-       struct mtd_part *p, *new;
-       uint64_t start, end;
+       struct mtd_part *new;
        int ret = 0;
 
        /* the direct offset is expected */
@@ -607,21 +606,7 @@ int mtd_add_partition(struct mtd_info *master, const char *name,
        if (IS_ERR(new))
                return PTR_ERR(new);
 
-       start = offset;
-       end = offset + length;
-
        mutex_lock(&mtd_partitions_mutex);
-       list_for_each_entry(p, &mtd_partitions, list)
-               if (p->master == master) {
-                       if ((start >= p->offset) &&
-                           (start < (p->offset + p->mtd.size)))
-                               goto err_inv;
-
-                       if ((end >= p->offset) &&
-                           (end < (p->offset + p->mtd.size)))
-                               goto err_inv;
-               }
-
        list_add(&new->list, &mtd_partitions);
        mutex_unlock(&mtd_partitions_mutex);
 
@@ -630,10 +615,6 @@ int mtd_add_partition(struct mtd_info *master, const char *name,
        mtd_add_partition_attrs(new);
 
        return ret;
-err_inv:
-       mutex_unlock(&mtd_partitions_mutex);
-       free_partition(new);
-       return -EINVAL;
 }
 EXPORT_SYMBOL_GPL(mtd_add_partition);