block: remove the bd_bdi in struct block_device

Just retrieve the bdi from the disk.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20210809141744.1203023-6-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block/ioctl.c

@@ -506,7 +506,7 @@ static int blkdev_common_ioctl(struct block_device *bdev, fmode_t mode,
 	case BLKFRASET:
 		if(!capable(CAP_SYS_ADMIN))
 			return -EACCES;
-		bdev->bd_bdi->ra_pages = (arg * 512) / PAGE_SIZE;
+		bdev->bd_disk->bdi->ra_pages = (arg * 512) / PAGE_SIZE;
 		return 0;
 	case BLKRRPART:
 		return blkdev_reread_part(bdev, mode);
@@ -556,7 +556,8 @@ int blkdev_ioctl(struct block_device *bdev, fmode_t mode, unsigned cmd,
 	case BLKFRAGET:
 		if (!argp)
 			return -EINVAL;
-		return put_long(argp, (bdev->bd_bdi->ra_pages*PAGE_SIZE) / 512);
+		return put_long(argp,
+			(bdev->bd_disk->bdi->ra_pages * PAGE_SIZE) / 512);
 	case BLKGETSIZE:
 		size = i_size_read(bdev->bd_inode);
 		if ((size >> 9) > ~0UL)
@@ -628,7 +629,7 @@ long compat_blkdev_ioctl(struct file *file, unsigned cmd, unsigned long arg)
 		if (!argp)
 			return -EINVAL;
 		return compat_put_long(argp,
-			       (bdev->bd_bdi->ra_pages * PAGE_SIZE) / 512);
+			(bdev->bd_disk->bdi->ra_pages * PAGE_SIZE) / 512);
 	case BLKGETSIZE:
 		size = i_size_read(bdev->bd_inode);
 		if ((size >> 9) > ~0UL)

fs/block_dev.c

@@ -801,7 +801,6 @@ static struct inode *bdev_alloc_inode(struct super_block *sb)
 	if (!ei)
 		return NULL;
 	memset(&ei->bdev, 0, sizeof(ei->bdev));
-	ei->bdev.bd_bdi = &noop_backing_dev_info;
 	return &ei->vfs_inode;
 }
 
@@ -826,16 +825,11 @@ static void init_once(void *data)
 
 static void bdev_evict_inode(struct inode *inode)
 {
-	struct block_device *bdev = &BDEV_I(inode)->bdev;
 	truncate_inode_pages_final(&inode->i_data);
 	invalidate_inode_buffers(inode); /* is it needed here? */
 	clear_inode(inode);
 	/* Detach inode from wb early as bdi_put() may free bdi->wb */
 	inode_detach_wb(inode);
-	if (bdev->bd_bdi != &noop_backing_dev_info) {
-		bdi_put(bdev->bd_bdi);
-		bdev->bd_bdi = &noop_backing_dev_info;
-	}
 }
 
 static const struct super_operations bdev_sops = {
@@ -1084,11 +1078,8 @@ static int blkdev_get_whole(struct block_device *bdev, fmode_t mode)
 		}
 	}
 
-	if (!bdev->bd_openers) {
+	if (!bdev->bd_openers)
 		set_init_blocksize(bdev);
-		if (bdev->bd_bdi == &noop_backing_dev_info)
-			bdev->bd_bdi = bdi_get(disk->bdi);
-	}
 	if (test_bit(GD_NEED_PART_SCAN, &disk->state))
 		bdev_disk_changed(disk, false);
 	bdev->bd_openers++;
@@ -1121,8 +1112,6 @@ static int blkdev_get_part(struct block_device *part, fmode_t mode)
 
 	disk->open_partitions++;
 	set_init_blocksize(part);
-	if (part->bd_bdi == &noop_backing_dev_info)
-		part->bd_bdi = bdi_get(disk->bdi);
 done:
 	part->bd_openers++;
 	return 0;

fs/nilfs2/super.c

@@ -1053,7 +1053,7 @@ nilfs_fill_super(struct super_block *sb, void *data, int silent)
 	sb->s_time_gran = 1;
 	sb->s_max_links = NILFS_LINK_MAX;
 
-	sb->s_bdi = bdi_get(sb->s_bdev->bd_bdi);
+	sb->s_bdi = bdi_get(sb->s_bdev->bd_disk->bdi);
 
 	err = load_nilfs(nilfs, sb);
 	if (err)

fs/super.c

@@ -1203,7 +1203,7 @@ static int set_bdev_super(struct super_block *s, void *data)
 {
 	s->s_bdev = data;
 	s->s_dev = s->s_bdev->bd_dev;
-	s->s_bdi = bdi_get(s->s_bdev->bd_bdi);
+	s->s_bdi = bdi_get(s->s_bdev->bd_disk->bdi);
 
 	if (blk_queue_stable_writes(s->s_bdev->bd_disk->queue))
 		s->s_iflags |= SB_I_STABLE_WRITES;

fs/xfs/xfs_buf.c

@@ -844,7 +844,7 @@ xfs_buf_readahead_map(
 {
 	struct xfs_buf		*bp;
 
-	if (bdi_read_congested(target->bt_bdev->bd_bdi))
+	if (bdi_read_congested(target->bt_bdev->bd_disk->bdi))
 		return;
 
 	xfs_buf_read_map(target, map, nmaps,

include/linux/backing-dev.h

@@ -143,7 +143,7 @@ static inline struct backing_dev_info *inode_to_bdi(struct inode *inode)
 	sb = inode->i_sb;
 #ifdef CONFIG_BLOCK
 	if (sb_is_blkdev_sb(sb))
-		return I_BDEV(inode)->bd_bdi;
+		return I_BDEV(inode)->bd_disk->bdi;
 #endif
 	return sb->s_bdi;
 }

include/linux/blk_types.h

@@ -38,7 +38,6 @@ struct block_device {
 	u8			bd_partno;
 	spinlock_t		bd_size_lock; /* for bd_inode->i_size updates */
 	struct gendisk *	bd_disk;
-	struct backing_dev_info *bd_bdi;
 
 	/* The counter of freeze processes */
 	int			bd_fsfreeze_count;