2020-08-18 05:50:14

by Tianxianting

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Subject: [PATCH] md: only calculate blocksize once and use i_blocksize()

We alreday has the interface i_blocksize(), which can be used
to get blocksize, so use it.
Only calculate blocksize once and use it within read_page().

Signed-off-by: Xianting Tian <[email protected]>
---
drivers/md/md-bitmap.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/md/md-bitmap.c b/drivers/md/md-bitmap.c
index 95a5f3757..0d5544868 100644
--- a/drivers/md/md-bitmap.c
+++ b/drivers/md/md-bitmap.c
@@ -357,11 +357,12 @@ static int read_page(struct file *file, unsigned long index,
struct inode *inode = file_inode(file);
struct buffer_head *bh;
sector_t block, blk_cur;
+ unsigned long blocksize = i_blocksize(inode);

pr_debug("read bitmap file (%dB @ %llu)\n", (int)PAGE_SIZE,
(unsigned long long)index << PAGE_SHIFT);

- bh = alloc_page_buffers(page, 1<<inode->i_blkbits, false);
+ bh = alloc_page_buffers(page, blocksize, false);
if (!bh) {
ret = -ENOMEM;
goto out;
@@ -383,10 +384,10 @@ static int read_page(struct file *file, unsigned long index,

bh->b_blocknr = block;
bh->b_bdev = inode->i_sb->s_bdev;
- if (count < (1<<inode->i_blkbits))
+ if (count < blocksize)
count = 0;
else
- count -= (1<<inode->i_blkbits);
+ count -= blocksize;

bh->b_end_io = end_bitmap_write;
bh->b_private = bitmap;
--
2.17.1


2020-08-20 00:36:17

by Song Liu

[permalink] [raw]
Subject: Re: [PATCH] md: only calculate blocksize once and use i_blocksize()

On Mon, Aug 17, 2020 at 10:49 PM Xianting Tian <[email protected]> wrote:
>
> We alreday has the interface i_blocksize(), which can be used
> to get blocksize, so use it.
> Only calculate blocksize once and use it within read_page().
>
> Signed-off-by: Xianting Tian <[email protected]>

Thanks for the patch. Applied to md-next.