[PATCH] IB/mlx5: Fix a parameter of find_first_bit

From: Christophe JAILLET
Date: Fri Aug 26 2016 - 01:25:03 EST


The 2nd parameter of 'find_first_bit' is the number of bits to search.
In this case, we are passing 'sizeof(tmp)' which is likely to be 4 or 8
because 'tmp' is an 'unsigned long'.

It is likely that the number of bits of 'tmp' was expected here. So use
BITS_PER_LONG instead.

It has been spotted by the following coccinelle script:
@@
expression ret, x;

@@
* ret = \(find_first_bit \| find_first_zero_bit\) (x, sizeof(...));

Signed-off-by: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx>
---
__ffs could be used to reduce code verbosity
---
drivers/infiniband/hw/mlx5/mem.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/infiniband/hw/mlx5/mem.c b/drivers/infiniband/hw/mlx5/mem.c
index 40df2cca0609..996b54e366b0 100644
--- a/drivers/infiniband/hw/mlx5/mem.c
+++ b/drivers/infiniband/hw/mlx5/mem.c
@@ -71,7 +71,7 @@ void mlx5_ib_cont_pages(struct ib_umem *umem, u64 addr, int *count, int *shift,

addr = addr >> page_shift;
tmp = (unsigned long)addr;
- m = find_first_bit(&tmp, sizeof(tmp));
+ m = find_first_bit(&tmp, BITS_PER_LONG);
skip = 1 << m;
mask = skip - 1;
i = 0;
@@ -81,7 +81,7 @@ void mlx5_ib_cont_pages(struct ib_umem *umem, u64 addr, int *count, int *shift,
for (k = 0; k < len; k++) {
if (!(i & mask)) {
tmp = (unsigned long)pfn;
- m = min_t(unsigned long, m, find_first_bit(&tmp, sizeof(tmp)));
+ m = min_t(unsigned long, m, find_first_bit(&tmp, BITS_PER_LONG));
skip = 1 << m;
mask = skip - 1;
base = pfn;
@@ -89,7 +89,7 @@ void mlx5_ib_cont_pages(struct ib_umem *umem, u64 addr, int *count, int *shift,
} else {
if (base + p != pfn) {
tmp = (unsigned long)p;
- m = find_first_bit(&tmp, sizeof(tmp));
+ m = find_first_bit(&tmp, BITS_PER_LONG);
skip = 1 << m;
mask = skip - 1;
base = pfn;
--
2.7.4


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