Received-SPF: pass (google.com: domain of linux-kernel+bounces-94043-linux.lists.archive=gmail.com@vger.kernel.org designates 147.75.48.161 as permitted sender) client-ip=147.75.48.161;
From: Ryusuke Konishi <konishi.ryusuke@gmail.com>
To: Andrew Morton <akpm@linux-foundation.org>
Cc: linux-nilfs@vger.kernel.org,
	linux-kernel@vger.kernel.org
Subject: [PATCH] nilfs2: Use div64_ul() instead of do_div()
Date: Wed,  6 Mar 2024 23:25:47 +0900
Message-Id: <20240306142547.4612-1-konishi.ryusuke@gmail.com>
Precedence: bulk
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit

From: Thorsten Blum <thorsten.blum@toblux.com>

Fixes Coccinelle/coccicheck warnings reported by do_div.cocci.

Compared to do_div(), div64_ul() does not implicitly cast the divisor and
does not unnecessarily calculate the remainder.

Link: https://lkml.kernel.org/r/20240229210456.63234-2-thorsten.blum@toblux.com
Signed-off-by: Thorsten Blum <thorsten.blum@toblux.com>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
---
Hi Andrew,

Could you please add this to the queue for the merge window?
It's a little late addition, so if this doesn't make it to the
upcoming merge window, please queue it for the next one.

Thanks,
Ryusuke Konishi

 fs/nilfs2/cpfile.c    | 2 +-
 fs/nilfs2/dat.c       | 2 +-
 fs/nilfs2/ioctl.c     | 4 ++--
 fs/nilfs2/sufile.c    | 2 +-
 fs/nilfs2/super.c     | 2 +-
 fs/nilfs2/the_nilfs.c | 2 +-
 6 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/fs/nilfs2/cpfile.c b/fs/nilfs2/cpfile.c
index 2c57132584de..69a5cced1e84 100644
--- a/fs/nilfs2/cpfile.c
+++ b/fs/nilfs2/cpfile.c
@@ -28,7 +28,7 @@ nilfs_cpfile_get_blkoff(const struct inode *cpfile, __u64 cno)
 {
 	__u64 tcno = cno + NILFS_MDT(cpfile)->mi_first_entry_offset - 1;
 
-	do_div(tcno, nilfs_cpfile_checkpoints_per_block(cpfile));
+	tcno = div64_ul(tcno, nilfs_cpfile_checkpoints_per_block(cpfile));
 	return (unsigned long)tcno;
 }
 
diff --git a/fs/nilfs2/dat.c b/fs/nilfs2/dat.c
index 8f71f8b0e218..180fc8d36213 100644
--- a/fs/nilfs2/dat.c
+++ b/fs/nilfs2/dat.c
@@ -460,7 +460,7 @@ ssize_t nilfs_dat_get_vinfo(struct inode *dat, void *buf, unsigned int visz,
 		kaddr = kmap_local_page(entry_bh->b_page);
 		/* last virtual block number in this block */
 		first = vinfo->vi_vblocknr;
-		do_div(first, entries_per_block);
+		first = div64_ul(first, entries_per_block);
 		first *= entries_per_block;
 		last = first + entries_per_block - 1;
 		for (j = i, n = 0;
diff --git a/fs/nilfs2/ioctl.c b/fs/nilfs2/ioctl.c
index cfb6aca5ec38..f1a01c191cf5 100644
--- a/fs/nilfs2/ioctl.c
+++ b/fs/nilfs2/ioctl.c
@@ -1111,7 +1111,7 @@ static int nilfs_ioctl_set_alloc_range(struct inode *inode, void __user *argp)
 	segbytes = nilfs->ns_blocks_per_segment * nilfs->ns_blocksize;
 
 	minseg = range[0] + segbytes - 1;
-	do_div(minseg, segbytes);
+	minseg = div64_ul(minseg, segbytes);
 
 	if (range[1] < 4096)
 		goto out;
@@ -1120,7 +1120,7 @@ static int nilfs_ioctl_set_alloc_range(struct inode *inode, void __user *argp)
 	if (maxseg < segbytes)
 		goto out;
 
-	do_div(maxseg, segbytes);
+	maxseg = div64_ul(maxseg, segbytes);
 	maxseg--;
 
 	ret = nilfs_sufile_set_alloc_range(nilfs->ns_sufile, minseg, maxseg);
diff --git a/fs/nilfs2/sufile.c b/fs/nilfs2/sufile.c
index abf05dc5750c..6748218be7c5 100644
--- a/fs/nilfs2/sufile.c
+++ b/fs/nilfs2/sufile.c
@@ -48,7 +48,7 @@ nilfs_sufile_get_blkoff(const struct inode *sufile, __u64 segnum)
 {
 	__u64 t = segnum + NILFS_MDT(sufile)->mi_first_entry_offset;
 
-	do_div(t, nilfs_sufile_segment_usages_per_block(sufile));
+	t = div64_ul(t, nilfs_sufile_segment_usages_per_block(sufile));
 	return (unsigned long)t;
 }
 
diff --git a/fs/nilfs2/super.c b/fs/nilfs2/super.c
index 5e630c179a1e..ac24ed109ce9 100644
--- a/fs/nilfs2/super.c
+++ b/fs/nilfs2/super.c
@@ -448,7 +448,7 @@ int nilfs_resize_fs(struct super_block *sb, __u64 newsize)
 
 	sb2off = NILFS_SB2_OFFSET_BYTES(newsize);
 	newnsegs = sb2off >> nilfs->ns_blocksize_bits;
-	do_div(newnsegs, nilfs->ns_blocks_per_segment);
+	newnsegs = div64_ul(newnsegs, nilfs->ns_blocks_per_segment);
 
 	ret = nilfs_sufile_resize(nilfs->ns_sufile, newnsegs);
 	up_write(&nilfs->ns_segctor_sem);
diff --git a/fs/nilfs2/the_nilfs.c b/fs/nilfs2/the_nilfs.c
index 71400496ed36..2ae2c1bbf6d1 100644
--- a/fs/nilfs2/the_nilfs.c
+++ b/fs/nilfs2/the_nilfs.c
@@ -413,7 +413,7 @@ static u64 nilfs_max_segment_count(struct the_nilfs *nilfs)
 {
 	u64 max_count = U64_MAX;
 
-	do_div(max_count, nilfs->ns_blocks_per_segment);
+	max_count = div64_ul(max_count, nilfs->ns_blocks_per_segment);
 	return min_t(u64, max_count, ULONG_MAX);
 }
 
-- 
2.34.1