md: add a new parameter 'offset' to md_super_write()

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.

Also rename md_super_write to md_write_metadata since there is nothing
super-block specific.

Link: https://lore.kernel.org/linux-raid/20250829080426.1441678-2-yukuai1@huaweicloud.com
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Xiao Ni <xni@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Li Nan <linan122@huawei.com>

diff --git a/drivers/md/md-bitmap.c b/drivers/md/md-bitmap.c
index 5f62f2fd8f3f3bd51f4cff264c0971fee92db59d..b157119de123fa3d534fcb71649cad634e1355ec 100644 (file)
--- a/drivers/md/md-bitmap.c
+++ b/drivers/md/md-bitmap.c
@@ -485,7 +485,8 @@ 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_write_metadata(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 fbc107b52819aa226a7a87358ca8b75ea2bffe68..528c993964580a87c1fc60f69dd0b8fc5bd4a4f8 100644 (file)
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -1038,15 +1038,26 @@ static void super_written(struct bio *bio)
                wake_up(&mddev->sb_wait);
 }
 
-void md_super_write(struct mddev *mddev, struct md_rdev *rdev,
-                  sector_t sector, int size, struct page *page)
-{
-       /* write first size bytes of page to sector of rdev
-        * Increment mddev->pending_writes before returning
-        * and decrement it on completion, waking up sb_wait
-        * if zero is reached.
-        * If an error occurred, call md_error
-        */
+/**
+ * md_write_metadata - write metadata to underlying disk, including
+ * array superblock, badblocks, bitmap superblock and bitmap bits.
+ * @mddev:     the array to write
+ * @rdev:      the underlying disk to write
+ * @sector:    the offset to @rdev
+ * @size:      the length of the metadata
+ * @page:      the metadata
+ * @offset:    the offset to @page
+ *
+ * Write @size bytes of @page start from @offset, to @sector of @rdev, Increment
+ * mddev->pending_writes before returning, and decrement it on completion,
+ * waking up sb_wait. Caller must call md_super_wait() after issuing io to all
+ * rdev. If an error occurred, md_error() will be called, and the @rdev will be
+ * kicked out from @mddev.
+ */
+void md_write_metadata(struct mddev *mddev, struct md_rdev *rdev,
+                      sector_t sector, int size, struct page *page,
+                      unsigned int offset)
+{
        struct bio *bio;
 
        if (!page)
@@ -1064,7 +1075,7 @@ 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;
 
@@ -1674,8 +1685,8 @@ super_90_rdev_size_change(struct md_rdev *rdev, sector_t num_sectors)
        if ((u64)num_sectors >= (2ULL << 32) && rdev->mddev->level >= 1)
                num_sectors = (sector_t)(2ULL << 32) - 2;
        do {
-               md_super_write(rdev->mddev, rdev, rdev->sb_start, rdev->sb_size,
-                      rdev->sb_page);
+               md_write_metadata(rdev->mddev, rdev, rdev->sb_start,
+                                 rdev->sb_size, rdev->sb_page, 0);
        } while (md_super_wait(rdev->mddev) < 0);
        return num_sectors;
 }
@@ -2323,8 +2334,8 @@ super_1_rdev_size_change(struct md_rdev *rdev, sector_t num_sectors)
        sb->super_offset = cpu_to_le64(rdev->sb_start);
        sb->sb_csum = calc_sb_1_csum(sb);
        do {
-               md_super_write(rdev->mddev, rdev, rdev->sb_start, rdev->sb_size,
-                              rdev->sb_page);
+               md_write_metadata(rdev->mddev, rdev, rdev->sb_start,
+                                 rdev->sb_size, rdev->sb_page, 0);
        } while (md_super_wait(rdev->mddev) < 0);
        return num_sectors;
 
@@ -2833,18 +2844,17 @@ rewrite:
                        continue; /* no noise on spare devices */
 
                if (!test_bit(Faulty, &rdev->flags)) {
-                       md_super_write(mddev,rdev,
-                                      rdev->sb_start, rdev->sb_size,
-                                      rdev->sb_page);
+                       md_write_metadata(mddev, rdev, rdev->sb_start,
+                                         rdev->sb_size, rdev->sb_page, 0);
                        pr_debug("md: (write) %pg's sb offset: %llu\n",
                                 rdev->bdev,
                                 (unsigned long long)rdev->sb_start);
                        rdev->sb_events = mddev->events;
                        if (rdev->badblocks.size) {
-                               md_super_write(mddev, rdev,
-                                              rdev->badblocks.sector,
-                                              rdev->badblocks.size << 9,
-                                              rdev->bb_page);
+                               md_write_metadata(mddev, rdev,
+                                                 rdev->badblocks.sector,
+                                                 rdev->badblocks.size << 9,
+                                                 rdev->bb_page, 0);
                                rdev->badblocks.size = 0;
                        }
 

diff --git a/drivers/md/md.h b/drivers/md/md.h
index 081152c8de1fd638bf8e35ff69fcf8ccbdc360e1..cadd9bc99938e544aebe76fb511e649643508a96 100644 (file)
--- a/drivers/md/md.h
+++ b/drivers/md/md.h
@@ -908,8 +908,9 @@ void md_account_bio(struct mddev *mddev, struct bio **bio);
 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);
+void md_write_metadata(struct mddev *mddev, struct md_rdev *rdev,
+                      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);