linux-kernel - [PATCH 1/7] staging: vc04_services: Using macro DIV_ROUND

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Date:   Wed, 22 Feb 2017 00:21:03 +0530
From:   simran singhal <singhalsimran0@...il.com>
To:     abbotti@....co.uk
Cc:     hsweeten@...ionengravers.com, gregkh@...uxfoundation.org,
        devel@...verdev.osuosl.org, linux-kernel@...r.kernel.org,
        outreachy-kernel@...glegroups.com
Subject: [PATCH 1/7] staging: vc04_services: Using macro DIV_ROUND_UP

The macro DIV_ROUND_UP performs the computation (((n) + (d) - 1) /(d)).
It clarifies the divisor calculations. This occurence was detected using
the coccinelle script:

@@
expression e1;
expression e2;
@@
(
- ((e1) + e2 - 1) / (e2)
+ DIV_ROUND_UP(e1,e2)
|
- ((e1) + (e2 - 1)) / (e2)
+ DIV_ROUND_UP(e1,e2)
)

Signed-off-by: simran singhal <singhalsimran0@...il.com>
---
 drivers/staging/vc04_services/interface/vchiq_arm/vchiq_2835_arm.c | 2 +-
 drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c      | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_2835_arm.c b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_2835_arm.c
index e6241fb..e09731e 100644
--- a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_2835_arm.c
+++ b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_2835_arm.c
@@ -400,7 +400,7 @@ create_pagelist(char __user *buf, size_t count, unsigned short type,
 	dma_addr_t dma_addr;
 
 	offset = ((unsigned int)(unsigned long)buf & (PAGE_SIZE - 1));
-	num_pages = (count + offset + PAGE_SIZE - 1) / PAGE_SIZE;
+	num_pages = DIV_ROUND_UP(count + offset, PAGE_SIZE);
 
 	pagelist_size = sizeof(PAGELIST_T) +
 			(num_pages * sizeof(u32)) +
diff --git a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c
index 0525211..d0938de 100644
--- a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c
+++ b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c
@@ -1557,7 +1557,7 @@ dump_phys_mem(void *virt_addr, u32 num_bytes)
 	offset = (int)(long)virt_addr & (PAGE_SIZE - 1);
 	end_offset = (int)(long)end_virt_addr & (PAGE_SIZE - 1);
 
-	num_pages = (offset + num_bytes + PAGE_SIZE - 1) / PAGE_SIZE;
+	num_pages = DIV_ROUND_UP(offset + num_bytes, PAGE_SIZE);
 
 	pages = kmalloc(sizeof(struct page *) * num_pages, GFP_KERNEL);
 	if (pages == NULL) {
-- 
2.7.4