From a954ea812018a84d350b316c39a2be3edc4b7ca8 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Mon, 23 Nov 2020 13:29:55 +0100 Subject: [PATCH] block: remove ->bd_contains Now that each hd_struct has a reference to the corresponding block_device, there is no need for the bd_contains pointer. Add a bdev_whole() helper to look up the whole device block_device struture instead. Signed-off-by: Christoph Hellwig Reviewed-by: Greg Kroah-Hartman Reviewed-by: Jan Kara Reviewed-by: Hannes Reinecke Acked-by: Tejun Heo Signed-off-by: Jens Axboe --- drivers/block/loop.c | 2 +- drivers/scsi/scsicam.c | 2 +- fs/block_dev.c | 22 ++++++++-------------- include/linux/blk_types.h | 4 +++- 4 files changed, 13 insertions(+), 17 deletions(-) diff --git a/drivers/block/loop.c b/drivers/block/loop.c index 26c7aafba7c5..c0df88b3300c 100644 --- a/drivers/block/loop.c +++ b/drivers/block/loop.c @@ -1088,7 +1088,7 @@ static int loop_configure(struct loop_device *lo, fmode_t mode, * here to avoid changing device under exclusive owner. */ if (!(mode & FMODE_EXCL)) { - claimed_bdev = bdev->bd_contains; + claimed_bdev = bdev_whole(bdev); error = bd_prepare_to_claim(bdev, claimed_bdev, loop_configure); if (error) goto out_putf; diff --git a/drivers/scsi/scsicam.c b/drivers/scsi/scsicam.c index 682cf08ab041..f1553a453616 100644 --- a/drivers/scsi/scsicam.c +++ b/drivers/scsi/scsicam.c @@ -32,7 +32,7 @@ */ unsigned char *scsi_bios_ptable(struct block_device *dev) { - struct address_space *mapping = dev->bd_contains->bd_inode->i_mapping; + struct address_space *mapping = bdev_whole(dev)->bd_inode->i_mapping; unsigned char *res = NULL; struct page *page; diff --git a/fs/block_dev.c b/fs/block_dev.c index b350ed3af83b..94baee369d26 100644 --- a/fs/block_dev.c +++ b/fs/block_dev.c @@ -119,7 +119,7 @@ int truncate_bdev_range(struct block_device *bdev, fmode_t mode, * under live filesystem. */ if (!(mode & FMODE_EXCL)) { - claimed_bdev = bdev->bd_contains; + claimed_bdev = bdev_whole(bdev); err = bd_prepare_to_claim(bdev, claimed_bdev, truncate_bdev_range); if (err) @@ -880,7 +880,6 @@ struct block_device *bdev_alloc(struct gendisk *disk, u8 partno) spin_lock_init(&bdev->bd_size_lock); bdev->bd_disk = disk; bdev->bd_partno = partno; - bdev->bd_contains = NULL; bdev->bd_super = NULL; bdev->bd_inode = inode; bdev->bd_part_count = 0; @@ -1347,9 +1346,7 @@ static int __blkdev_get(struct block_device *bdev, fmode_t mode) int ret; if (!bdev->bd_openers) { - bdev->bd_contains = bdev; - - if (!bdev->bd_partno) { + if (!bdev_is_partition(bdev)) { ret = -ENXIO; bdev->bd_part = disk_get_part(disk, 0); if (!bdev->bd_part) @@ -1389,7 +1386,6 @@ static int __blkdev_get(struct block_device *bdev, fmode_t mode) whole->bd_part_count++; mutex_unlock(&whole->bd_mutex); - bdev->bd_contains = whole; bdev->bd_part = disk_get_part(disk, bdev->bd_partno); if (!(disk->flags & GENHD_FL_UP) || !bdev->bd_part || !bdev->bd_part->nr_sects) { @@ -1405,7 +1401,7 @@ static int __blkdev_get(struct block_device *bdev, fmode_t mode) if (bdev->bd_bdi == &noop_backing_dev_info) bdev->bd_bdi = bdi_get(disk->queue->backing_dev_info); } else { - if (bdev->bd_contains == bdev) { + if (!bdev_is_partition(bdev)) { ret = 0; if (bdev->bd_disk->fops->open) ret = bdev->bd_disk->fops->open(bdev, mode); @@ -1423,7 +1419,6 @@ static int __blkdev_get(struct block_device *bdev, fmode_t mode) out_clear: disk_put_part(bdev->bd_part); bdev->bd_part = NULL; - bdev->bd_contains = NULL; return ret; } @@ -1670,8 +1665,7 @@ static void __blkdev_put(struct block_device *bdev, fmode_t mode, int for_part) disk_put_part(bdev->bd_part); bdev->bd_part = NULL; if (bdev_is_partition(bdev)) - victim = bdev->bd_contains; - bdev->bd_contains = NULL; + victim = bdev_whole(bdev); } else { if (!bdev_is_partition(bdev) && disk->fops->release) disk->fops->release(disk, mode); @@ -1690,6 +1684,7 @@ void blkdev_put(struct block_device *bdev, fmode_t mode) mutex_lock(&bdev->bd_mutex); if (mode & FMODE_EXCL) { + struct block_device *whole = bdev_whole(bdev); bool bdev_free; /* @@ -1700,13 +1695,12 @@ void blkdev_put(struct block_device *bdev, fmode_t mode) spin_lock(&bdev_lock); WARN_ON_ONCE(--bdev->bd_holders < 0); - WARN_ON_ONCE(--bdev->bd_contains->bd_holders < 0); + WARN_ON_ONCE(--whole->bd_holders < 0); - /* bd_contains might point to self, check in a separate step */ if ((bdev_free = !bdev->bd_holders)) bdev->bd_holder = NULL; - if (!bdev->bd_contains->bd_holders) - bdev->bd_contains->bd_holder = NULL; + if (!whole->bd_holders) + whole->bd_holder = NULL; spin_unlock(&bdev_lock); diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h index 9698f459cc65..2e0a9bd9688d 100644 --- a/include/linux/blk_types.h +++ b/include/linux/blk_types.h @@ -32,7 +32,6 @@ struct block_device { #ifdef CONFIG_SYSFS struct list_head bd_holder_disks; #endif - struct block_device * bd_contains; u8 bd_partno; struct hd_struct * bd_part; /* number of times partitions within this device have been opened. */ @@ -49,6 +48,9 @@ struct block_device { struct super_block *bd_fsfreeze_sb; } __randomize_layout; +#define bdev_whole(_bdev) \ + ((_bdev)->bd_disk->part0.bdev) + #define bdev_kobj(_bdev) \ (&part_to_dev((_bdev)->bd_part)->kobj) -- 2.20.1