dm stripe: use struct_size() in kmalloc()

One of the more common cases of allocation size calculations is finding
the size of a structure that has a zero-sized array at the end, along
with memory for some number of elements for that array. For example:

struct stripe_c {
        ...
        struct stripe stripe[0];
};

In this case alloc_context() and dm_array_too_big() are removed and
replaced by the direct use of the struct_size() helper in kmalloc().

Notice that open-coded form is prone to type mistakes.

This code was detected with the help of Coccinelle.

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

1 files changed, 0 insertions, 3 deletions

diff --git a/include/linux/device-mapper.h b/include/linux/device-mapper.h
index 399ad8632356..2e13826898b2 100644
--- a/include/linux/device-mapper.h
+++ b/include/linux/device-mapper.h
@@ -594,9 +594,6 @@ void *dm_vcalloc(unsigned long nmemb, unsigned long elem_size);
  */
 #define dm_round_up(n, sz) (dm_div_up((n), (sz)) * (sz))
 
-#define dm_array_too_big(fixed, obj, num) \
-	((num) > (UINT_MAX - (fixed)) / (obj))
-
 /*
  * Sector offset taken relative to the start of the target instead of
  * relative to the start of the device.