Commit 65f8e625 authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Jens Axboe
Browse files

gfs2: use bdev_rw_virt in gfs2_read_super 



Switch gfs2_read_super to allocate the superblock buffer using kmalloc
which falls back to the page allocator for PAGE_SIZE allocation but
gives us a kernel virtual address and then use bdev_rw_virt to perform
the synchronous read into it.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarAndreas Gruenbacher <agruenba@redhat.com>
Reviewed-by: default avatarDamien Le Moal <dlemoal@kernel.org>
Link: https://lore.kernel.org/r/20250507120451.4000627-11-hch@lst.de


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent a2160813

fs/gfs2/ops_fstype.c

+9 −15
Original line number Diff line number Diff line
@@ -226,28 +226,22 @@ static void gfs2_sb_in(struct gfs2_sbd *sdp, const struct gfs2_sb *str) 


static int gfs2_read_super(struct gfs2_sbd *sdp, sector_t sector, int silent)

{

	struct super_block *sb = sdp->sd_vfs;

	struct page *page;

	struct bio_vec bvec;

	struct bio bio;

	struct gfs2_sb *sb;

	int err;



	page = alloc_page(GFP_KERNEL);

	if (unlikely(!page))

	sb = kmalloc(PAGE_SIZE, GFP_KERNEL);

	if (unlikely(!sb))

		return -ENOMEM;



	bio_init(&bio, sb->s_bdev, &bvec, 1, REQ_OP_READ | REQ_META);

	bio.bi_iter.bi_sector = sector * (sb->s_blocksize >> 9);

	__bio_add_page(&bio, page, PAGE_SIZE, 0);



	err = submit_bio_wait(&bio);

	err = bdev_rw_virt(sdp->sd_vfs->s_bdev,

			sector * (sdp->sd_vfs->s_blocksize >> 9), sb, PAGE_SIZE,

			REQ_OP_READ | REQ_META);

	if (err) {

		pr_warn("error %d reading superblock\n", err);

		__free_page(page);

		kfree(sb);

		return err;

	}

	gfs2_sb_in(sdp, page_address(page));

	__free_page(page);

	gfs2_sb_in(sdp, sb);

	kfree(sb);

	return gfs2_check_sb(sdp, silent);

}