On Jun 14, 2023, at 11:48 PM, Christoph Hellwig [off-list ref] wrote:

Diretly apply mddev->bitmap_info.offset to the sector number to read
instead of doing that in both callers.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
drivers/md/md-bitmap.c | 17 ++++++++---------
1 file changed, 8 insertions(+), 9 deletions(-)

diff --git a/drivers/md/md-bitmap.c b/drivers/md/md-bitmap.c
index f4bff2dfe2fd8f..39ff75cc7a16ac 100644
--- a/drivers/md/md-bitmap.c
+++ b/drivers/md/md-bitmap.c

@@ -145,7 +145,8 @@ static int read_sb_page(struct mddev *mddev, loff_t offset,

struct page *page, unsigned long index, int size)
{

- sector_t sector = offset + index * (PAGE_SIZE / SECTOR_SIZE);
+ sector_t sector = mddev->bitmap_info.offset + offset +
+ index * (PAGE_SIZE / SECTOR_SIZE);
struct md_rdev *rdev;

rdev_for_each(rdev, mddev) {

@@ -593,7 +594,7 @@ static int md_bitmap_read_sb(struct bitmap *bitmap)

unsigned long sectors_reserved = 0;
int err = -EINVAL;
struct page *sb_page;
- loff_t offset = bitmap->mddev->bitmap_info.offset;
+ loff_t offset = 0;

if (!bitmap->storage.file && !bitmap->mddev->bitmap_info.offset) {
chunksize = 128 * 1024 * 1024;

@@ -620,7 +621,7 @@ static int md_bitmap_read_sb(struct bitmap *bitmap)

bm_blocks = ((bm_blocks+7) >> 3) + sizeof(bitmap_super_t);
/* to 4k blocks */
bm_blocks = DIV_ROUND_UP_SECTOR_T(bm_blocks, 4096);
- offset = bitmap->mddev->bitmap_info.offset + (bitmap->cluster_slot * (bm_blocks << 3));
+ offset = bitmap->cluster_slot * (bm_blocks << 3);
pr_debug("%s:%d bm slot: %d offset: %llu\n", __func__, __LINE__,
bitmap->cluster_slot, offset);
}

@@ -632,10 +633,8 @@ static int md_bitmap_read_sb(struct bitmap *bitmap)

err = read_file_page(bitmap->storage.file, 0,
bitmap, bytes, sb_page);
} else {
- err = read_sb_page(bitmap->mddev,
-   offset,
-   sb_page,
-   0, sizeof(bitmap_super_t));
+ err = read_sb_page(bitmap->mddev, offset, sb_page, 0,
+   sizeof(bitmap_super_t));
}
if (err)
return err;

@@ -1127,8 +1126,8 @@ static int md_bitmap_init_from_disk(struct bitmap *bitmap, sector_t start)

if (file)
ret = read_file_page(file, i, bitmap, count, page);
else
- ret = read_sb_page(mddev, mddev->bitmap_info.offset,
-   page, i + node_offset, count);
+ ret = read_sb_page(mddev, 0, page, i + node_offset,
+   count);
if (ret)
goto err;
}
-- 
2.39.2