[PATCH] nilfs2: Use div64_ul() instead of do_div()

From: Ryusuke Konishi
Date: Wed Mar 06 2024 - 09:26:02 EST


From: Thorsten Blum <thorsten.blum@xxxxxxxxxx>

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@xxxxxxxxxx
Signed-off-by: Thorsten Blum <thorsten.blum@xxxxxxxxxx>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@xxxxxxxxx>
---
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