Re: [PATCH 13/17] btrfs: use bdev_rw_virt in scrub_one_super

[Qu Wenruo]

在 2025/4/22 23:56, Christoph Hellwig 写道:
Replace the code building a bio from a kernel direct map address and
submitting it synchronously with the bdev_rw_virt helper.

Signed-off-by: Christoph Hellwig <h...@lst.de>

Reviewed-by: Qu Wenruo <w...@suse.com>

In fact I'm waiting for this helper to refactor how we do super block 
read/write, to get rid of any page cache usage of the block device.

Thanks,
Qu

---
  fs/btrfs/scrub.c | 10 ++--------
  1 file changed, 2 insertions(+), 8 deletions(-)

diff --git a/fs/btrfs/scrub.c b/fs/btrfs/scrub.c
index 2c5edcee9450..7bdb2bc0a212 100644
--- a/fs/btrfs/scrub.c
+++ b/fs/btrfs/scrub.c
@@ -2770,17 +2770,11 @@ static int scrub_one_super(struct scrub_ctx *sctx, 
struct btrfs_device *dev,
                           struct page *page, u64 physical, u64 generation)
  {
        struct btrfs_fs_info *fs_info = sctx->fs_info;
-       struct bio_vec bvec;
-       struct bio bio;
        struct btrfs_super_block *sb = page_address(page);
        int ret;
  
-	bio_init(&bio, dev->bdev, &bvec, 1, REQ_OP_READ);
-       bio.bi_iter.bi_sector = physical >> SECTOR_SHIFT;
-       __bio_add_page(&bio, page, BTRFS_SUPER_INFO_SIZE, 0);
-       ret = submit_bio_wait(&bio);
-       bio_uninit(&bio);
-
+       ret = bdev_rw_virt(dev->bdev, physical >> SECTOR_SHIFT, sb,
+                       BTRFS_SUPER_INFO_SIZE, REQ_OP_READ);
        if (ret < 0)
                return ret;
        ret = btrfs_check_super_csum(fs_info, sb);