There are tons of places where we need to get a request_queue only
having bdev, which turns into bdev->bd_disk->queue. There are probably a
hundred of such places considering inline helpers, and enough of them
are in hot paths.
Cache queue pointer in struct block_device and make use of it in
bdev_get_queue().
Signed-off-by: Pavel Begunkov <asml.silence@xxxxxxxxx>
---
block/bdev.c | 1 +
block/genhd.c | 4 +++-
include/linux/blk_types.h | 1 +
include/linux/blkdev.h | 2 +-
4 files changed, 6 insertions(+), 2 deletions(-)
diff --git a/block/bdev.c b/block/bdev.c
index 567534c63f3d..30ae5b5d5f91 100644
--- a/block/bdev.c
+++ b/block/bdev.c
@@ -494,6 +494,7 @@ struct block_device *bdev_alloc(struct gendisk *disk, u8 partno)
bdev->bd_disk = disk;
bdev->bd_partno = partno;
bdev->bd_inode = inode;
+ bdev->bd_queue = disk->queue;
bdev->bd_stats = alloc_percpu(struct disk_stats);
if (!bdev->bd_stats) {
iput(inode);
diff --git a/block/genhd.c b/block/genhd.c
index 5e8aa0ab66c2..e11ee23a4401 100644
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -1244,6 +1244,9 @@ struct gendisk *__alloc_disk_node(struct request_queue *q, int node_id,
if (!disk->bdi)
goto out_free_disk;
+ /* bdev_alloc() might need the queue, set before the first call */
+ disk->queue = q;
+
disk->part0 = bdev_alloc(disk, 0);
if (!disk->part0)
goto out_free_bdi;
@@ -1259,7 +1262,6 @@ struct gendisk *__alloc_disk_node(struct request_queue *q, int node_id,
disk_to_dev(disk)->type = &disk_type;
device_initialize(disk_to_dev(disk));
inc_diskseq(disk);
- disk->queue = q;
q->disk = disk;
lockdep_init_map(&disk->lockdep_map, "(bio completion)", lkclass, 0);
#ifdef CONFIG_BLOCK_HOLDER_DEPRECATED
diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h
index 72736b4c057c..1e370929c89e 100644
--- a/include/linux/blk_types.h
+++ b/include/linux/blk_types.h
@@ -38,6 +38,7 @@ struct block_device {
u8 bd_partno;
spinlock_t bd_size_lock; /* for bd_inode->i_size updates */
struct gendisk * bd_disk;
+ struct request_queue * bd_queue;
/* The counter of freeze processes */
int bd_fsfreeze_count;
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 2a8689e949b4..d5b21fc8f49e 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -574,7 +574,7 @@ int iocb_bio_iopoll(struct kiocb *kiocb, unsigned int flags);
static inline struct request_queue *bdev_get_queue(struct block_device *bdev)
{
- return bdev->bd_disk->queue; /* this is never NULL */
+ return bdev->bd_queue; /* this is never NULL */
}
/*
--
2.33.0
