md-bitmap: account for mddev->bitmap_info.offset in read_sb_page

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>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20230615064840.629492-9-hch@lst.de

diff --git a/drivers/md/md-bitmap.c b/drivers/md/md-bitmap.c
index c6dd1fa..ae1c6f4 100644 (file)
--- 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 @@ re_read:
                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 @@ re_read:
                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;
@@ -1128,8 +1127,8 @@ 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;
        }