[PATCH lib/bitmap 5/9] lib: bitmap: move ERANGE check from set_region to check_region

paulmck
2021-03-04T00:27:06Z

It makes sense to do all the checks in check_region() and not 1/2
in check_region and 1/2 in set_region.

Since set_region is called immediately after check_region, the net
effect on runtime is zero, but it gets rid of an if (...) return...

Cc: Yury Norov <yury.norov@gmail.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Yury Norov <yury.norov@gmail.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
---
lib/bitmap.c | 14 +++++---------
1 file changed, 5 insertions(+), 9 deletions(-)

diff --git a/lib/bitmap.c b/lib/bitmap.c
index 162e285..833f152a 100644
--- a/lib/bitmap.c
+++ b/lib/bitmap.c
@@ -500,17 +500,12 @@ struct region {
unsigned int nbits;
};

-static int bitmap_set_region(const struct region *r, unsigned long *bitmap)
+static void bitmap_set_region(const struct region *r, unsigned long *bitmap)
{
unsigned int start;

- if (r->end >= r->nbits)
- return -ERANGE;
-
for (start = r->start; start <= r->end; start += r->group_len)
bitmap_set(bitmap, start, min(r->end - start + 1, r->off));
-
- return 0;
}

static int bitmap_check_region(const struct region *r)
@@ -518,6 +513,9 @@ static int bitmap_check_region(const struct region *r)
if (r->start > r->end || r->group_len == 0 || r->off > r->group_len)
return -EINVAL;

+ if (r->end >= r->nbits)
+ return -ERANGE;
+
return 0;
}

@@ -656,9 +654,7 @@ int bitmap_parselist(const char *buf, unsigned long *maskp, int nmaskbits)
if (ret)
return ret;

- ret = bitmap_set_region(&r, maskp);
- if (ret)
- return ret;
+ bitmap_set_region(&r, maskp);
}

return 0;
--
2.9.5