diff options
author | Christoph Hellwig <hch@lst.de> | 2020-11-26 18:47:17 +0100 |
---|---|---|
committer | Jens Axboe <axboe@kernel.dk> | 2020-12-01 14:53:40 -0700 |
commit | cb8432d650fe3be58bb962bc8e602dc405510327 (patch) | |
tree | 5e893d44ba2449080db89f00098f11259384a56a /block/genhd.c | |
parent | 83950d359010a493462d58c712b1124c877d1b3b (diff) | |
download | linux-stable-cb8432d650fe3be58bb962bc8e602dc405510327.tar.gz linux-stable-cb8432d650fe3be58bb962bc8e602dc405510327.tar.bz2 linux-stable-cb8432d650fe3be58bb962bc8e602dc405510327.zip |
block: allocate struct hd_struct as part of struct bdev_inode
Allocate hd_struct together with struct block_device to pre-load
the lifetime rule changes in preparation of merging the two structures.
Note that part0 was previously embedded into struct gendisk, but is
a separate allocation now, and already points to the block_device instead
of the hd_struct. The lifetime of struct gendisk is still controlled by
the struct device embedded in the part0 hd_struct.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'block/genhd.c')
-rw-r--r-- | block/genhd.c | 50 |
1 files changed, 19 insertions, 31 deletions
diff --git a/block/genhd.c b/block/genhd.c index 2db1204920a9..c35b03dac5e5 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -42,7 +42,7 @@ static void disk_release_events(struct gendisk *disk); void set_capacity(struct gendisk *disk, sector_t sectors) { - struct block_device *bdev = disk->part0.bdev; + struct block_device *bdev = disk->part0; spin_lock(&bdev->bd_size_lock); i_size_write(bdev->bd_inode, (loff_t)sectors << SECTOR_SHIFT); @@ -318,9 +318,7 @@ static inline int sector_in_part(struct hd_struct *part, sector_t sector) * primarily used for stats accounting. * * CONTEXT: - * RCU read locked. The returned partition pointer is always valid - * because its refcount is grabbed except for part0, which lifetime - * is same with the disk. + * RCU read locked. * * RETURNS: * Found partition on success, part0 is returned if no partition matches @@ -336,26 +334,19 @@ struct hd_struct *disk_map_sector_rcu(struct gendisk *disk, sector_t sector) ptbl = rcu_dereference(disk->part_tbl); part = rcu_dereference(ptbl->last_lookup); - if (part && sector_in_part(part, sector) && hd_struct_try_get(part)) + if (part && sector_in_part(part, sector)) goto out_unlock; for (i = 1; i < ptbl->len; i++) { part = rcu_dereference(ptbl->part[i]); if (part && sector_in_part(part, sector)) { - /* - * only live partition can be cached for lookup, - * so use-after-free on cached & deleting partition - * can be avoided - */ - if (!hd_struct_try_get(part)) - break; rcu_assign_pointer(ptbl->last_lookup, part); goto out_unlock; } } - part = &disk->part0; + part = disk->part0->bd_part; out_unlock: rcu_read_unlock(); return part; @@ -681,8 +672,8 @@ static void register_disk(struct device *parent, struct gendisk *disk, */ pm_runtime_set_memalloc_noio(ddev, true); - disk->part0.bdev->bd_holder_dir = - kobject_create_and_add("holders", &ddev->kobj); + disk->part0->bd_holder_dir = + kobject_create_and_add("holders", &ddev->kobj); disk->slave_dir = kobject_create_and_add("slaves", &ddev->kobj); if (disk->flags & GENHD_FL_HIDDEN) { @@ -748,7 +739,7 @@ static void __device_add_disk(struct device *parent, struct gendisk *disk, disk->flags |= GENHD_FL_UP; - retval = blk_alloc_devt(&disk->part0, &devt); + retval = blk_alloc_devt(disk->part0->bd_part, &devt); if (retval) { WARN_ON(1); return; @@ -775,7 +766,7 @@ static void __device_add_disk(struct device *parent, struct gendisk *disk, ret = bdi_register(bdi, "%u:%u", MAJOR(devt), MINOR(devt)); WARN_ON(ret); bdi_set_owner(bdi, dev); - bdev_add(disk->part0.bdev, devt); + bdev_add(disk->part0, devt); } register_disk(parent, disk, groups); if (register_queue) @@ -888,11 +879,11 @@ void del_gendisk(struct gendisk *disk) blk_unregister_queue(disk); - kobject_put(disk->part0.bdev->bd_holder_dir); + kobject_put(disk->part0->bd_holder_dir); kobject_put(disk->slave_dir); - part_stat_set_all(&disk->part0, 0); - disk->part0.bdev->bd_stamp = 0; + part_stat_set_all(disk->part0->bd_part, 0); + disk->part0->bd_stamp = 0; if (!sysfs_deprecated) sysfs_remove_link(block_depr, dev_name(disk_to_dev(disk))); pm_runtime_set_memalloc_noio(disk_to_dev(disk), false); @@ -1005,7 +996,7 @@ void __init printk_all_partitions(void) */ disk_part_iter_init(&piter, disk, DISK_PITER_INCL_PART0); while ((part = disk_part_iter_next(&piter))) { - bool is_part0 = part == &disk->part0; + bool is_part0 = part == disk->part0->bd_part; printk("%s%s %10llu %s %s", is_part0 ? "" : " ", bdevt_str(part_devt(part), devt_buf), @@ -1460,7 +1451,7 @@ static void disk_release(struct device *dev) disk_release_events(disk); kfree(disk->random); disk_replace_part_tbl(disk, NULL); - hd_free_part(&disk->part0); + bdput(disk->part0); if (disk->queue) blk_put_queue(disk->queue); kfree(disk); @@ -1626,8 +1617,8 @@ struct gendisk *__alloc_disk_node(int minors, int node_id) if (!disk) return NULL; - disk->part0.bdev = bdev_alloc(disk, 0); - if (!disk->part0.bdev) + disk->part0 = bdev_alloc(disk, 0); + if (!disk->part0) goto out_free_disk; disk->node_id = node_id; @@ -1635,10 +1626,7 @@ struct gendisk *__alloc_disk_node(int minors, int node_id) goto out_bdput; ptbl = rcu_dereference_protected(disk->part_tbl, 1); - rcu_assign_pointer(ptbl->part[0], &disk->part0); - - if (hd_ref_init(&disk->part0)) - goto out_bdput; + rcu_assign_pointer(ptbl->part[0], disk->part0->bd_part); disk->minors = minors; rand_initialize_disk(disk); @@ -1648,7 +1636,7 @@ struct gendisk *__alloc_disk_node(int minors, int node_id) return disk; out_bdput: - bdput(disk->part0.bdev); + bdput(disk->part0); out_free_disk: kfree(disk); return NULL; @@ -1687,9 +1675,9 @@ void set_disk_ro(struct gendisk *disk, int flag) struct disk_part_iter piter; struct hd_struct *part; - if (disk->part0.bdev->bd_read_only != flag) { + if (disk->part0->bd_read_only != flag) { set_disk_ro_uevent(disk, flag); - disk->part0.bdev->bd_read_only = flag; + disk->part0->bd_read_only = flag; } disk_part_iter_init(&piter, disk, DISK_PITER_INCL_EMPTY); |