linux-kernel - [PATCH 4/5] tools/firmware/ihex2fw: Simplify next record offset calculation

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Message-Id: <20181221072841.30199-5-andrew.smirnov@gmail.com>
Date:   Thu, 20 Dec 2018 23:28:40 -0800
From:   Andrey Smirnov <andrew.smirnov@...il.com>
To:     linux-kernel <linux-kernel@...r.kernel.org>
Cc:     Andrey Smirnov <andrew.smirnov@...il.com>,
        Chris Healy <cphealy@...il.com>,
        Kyle McMartin <kyle@...nel.org>,
        Andrew Morton <akpm@...ux-foundation.org>,
        Masahiro Yamada <yamada.masahiro@...ionext.com>,
        David Woodhouse <dwmw2@...radead.org>,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>
Subject: [PATCH 4/5] tools/firmware/ihex2fw: Simplify next record offset calculation

We can convert original expression for 'writelen" to use ALIGN as
follows:

    (p->len + 9) & ~3 => (p->len + 6 + 3) & ~3 => ALIGN(p->len + 6, 4)

Now, subsituting "p->len + 6" with "p->len + sizeof(p->addr) +
sizeof(p->len)" we end up with the same expression as used by kernel
couterpart in linux/ihex.h:

    ALIGN(p->len + sizeof(p->addr) + sizeof(p->len), 4)

That is a full size of the record, aligned to 4 bytes. No functional
change intended.

Cc: Chris Healy <cphealy@...il.com>
Cc: Kyle McMartin <kyle@...nel.org>
Cc: Andrew Morton <akpm@...ux-foundation.org>
Cc: Masahiro Yamada <yamada.masahiro@...ionext.com>
Cc: David Woodhouse <dwmw2@...radead.org>
Cc: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
Cc: linux-kernel <linux-kernel@...r.kernel.org>
Signed-off-by: Andrey Smirnov <andrew.smirnov@...il.com>
---
 tools/firmware/ihex2fw.c | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/tools/firmware/ihex2fw.c b/tools/firmware/ihex2fw.c
index b58dd061e978..e081cef730d8 100644
--- a/tools/firmware/ihex2fw.c
+++ b/tools/firmware/ihex2fw.c
@@ -24,6 +24,10 @@
 #include <getopt.h>
 
 
+#define __ALIGN_KERNEL_MASK(x, mask)	(((x) + (mask)) & ~(mask))
+#define __ALIGN_KERNEL(x, a)		__ALIGN_KERNEL_MASK(x, (typeof(x))(a) - 1)
+#define ALIGN(x, a)			__ALIGN_KERNEL((x), (a))
+
 struct ihex_binrec {
 	struct ihex_binrec *next; /* not part of the real data structure */
         uint32_t addr;
@@ -259,13 +263,18 @@ static void file_record(struct ihex_binrec *record)
 	*p = record;
 }
 
+static uint16_t ihex_binrec_size(struct ihex_binrec *p)
+{
+	return p->len + sizeof(p->addr) + sizeof(p->len);
+}
+
 static int output_records(int outfd)
 {
 	unsigned char zeroes[6] = {0, 0, 0, 0, 0, 0};
 	struct ihex_binrec *p = records;
 
 	while (p) {
-		uint16_t writelen = (p->len + 9) & ~3;
+		uint16_t writelen = ALIGN(ihex_binrec_size(p), 4);
 
 		p->addr = htonl(p->addr);
 		p->len = htons(p->len);
-- 
2.19.1