[PATCH RFC md-6.16 v3 06/19] md: add a new parameter 'offset' to md_super_write()

[Yu Kuai]

From: Yu Kuai <yuku...@huawei.com>

The parameter is always set to 0 for now, following patches will use
this helper to write llbitmap to underlying disks, allow writing
dirty sectors instead of the whole page.

Signed-off-by: Yu Kuai <yuku...@huawei.com>
---
 drivers/md/md-bitmap.c |  3 ++-
 drivers/md/md.c        | 13 +++++++------
 drivers/md/md.h        |  3 ++-
 3 files changed, 11 insertions(+), 8 deletions(-)

diff --git a/drivers/md/md-bitmap.c b/drivers/md/md-bitmap.c
index 4c5067783b7a..a5602cb5d756 100644
--- a/drivers/md/md-bitmap.c
+++ b/drivers/md/md-bitmap.c
@@ -468,7 +468,8 @@ static int __write_sb_page(struct md_rdev *rdev, struct 
bitmap *bitmap,
                        return -EINVAL;
        }
 
-       md_super_write(mddev, rdev, sboff + ps, (int)min(size, bitmap_limit), 
page);
+       md_super_write(mddev, rdev, sboff + ps, (int)min(size, bitmap_limit),
+                      page, 0);
        return 0;
 }
 
diff --git a/drivers/md/md.c b/drivers/md/md.c
index ba2b981b017c..4329ecfbe8ff 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -1037,7 +1037,8 @@ static void super_written(struct bio *bio)
 }
 
 void md_super_write(struct mddev *mddev, struct md_rdev *rdev,
-                  sector_t sector, int size, struct page *page)
+                  sector_t sector, int size, struct page *page,
+                  unsigned int offset)
 {
        /* write first size bytes of page to sector of rdev
         * Increment mddev->pending_writes before returning
@@ -1062,7 +1063,7 @@ void md_super_write(struct mddev *mddev, struct md_rdev 
*rdev,
        atomic_inc(&rdev->nr_pending);
 
        bio->bi_iter.bi_sector = sector;
-       __bio_add_page(bio, page, size, 0);
+       __bio_add_page(bio, page, size, offset);
        bio->bi_private = rdev;
        bio->bi_end_io = super_written;
 
@@ -1673,7 +1674,7 @@ super_90_rdev_size_change(struct md_rdev *rdev, sector_t 
num_sectors)
                num_sectors = (sector_t)(2ULL << 32) - 2;
        do {
                md_super_write(rdev->mddev, rdev, rdev->sb_start, rdev->sb_size,
-                      rdev->sb_page);
+                              rdev->sb_page, 0);
        } while (md_super_wait(rdev->mddev) < 0);
        return num_sectors;
 }
@@ -2322,7 +2323,7 @@ super_1_rdev_size_change(struct md_rdev *rdev, sector_t 
num_sectors)
        sb->sb_csum = calc_sb_1_csum(sb);
        do {
                md_super_write(rdev->mddev, rdev, rdev->sb_start, rdev->sb_size,
-                              rdev->sb_page);
+                              rdev->sb_page, 0);
        } while (md_super_wait(rdev->mddev) < 0);
        return num_sectors;
 
@@ -2833,7 +2834,7 @@ void md_update_sb(struct mddev *mddev, int force_change)
                if (!test_bit(Faulty, &rdev->flags)) {
                        md_super_write(mddev,rdev,
                                       rdev->sb_start, rdev->sb_size,
-                                      rdev->sb_page);
+                                      rdev->sb_page, 0);
                        pr_debug("md: (write) %pg's sb offset: %llu\n",
                                 rdev->bdev,
                                 (unsigned long long)rdev->sb_start);
@@ -2842,7 +2843,7 @@ void md_update_sb(struct mddev *mddev, int force_change)
                                md_super_write(mddev, rdev,
                                               rdev->badblocks.sector,
                                               rdev->badblocks.size << 9,
-                                              rdev->bb_page);
+                                              rdev->bb_page, 0);
                                rdev->badblocks.size = 0;
                        }
 
diff --git a/drivers/md/md.h b/drivers/md/md.h
index 135d95ba1ebb..99f6c7a92b48 100644
--- a/drivers/md/md.h
+++ b/drivers/md/md.h
@@ -890,7 +890,8 @@ void md_free_cloned_bio(struct bio *bio);
 
 extern bool __must_check md_flush_request(struct mddev *mddev, struct bio 
*bio);
 extern void md_super_write(struct mddev *mddev, struct md_rdev *rdev,
-                          sector_t sector, int size, struct page *page);
+                          sector_t sector, int size, struct page *page,
+                          unsigned int offset);
 extern int md_super_wait(struct mddev *mddev);
 extern int sync_page_io(struct md_rdev *rdev, sector_t sector, int size,
                struct page *page, blk_opf_t opf, bool metadata_op);
-- 
2.39.2