From: Al Viro Date: Fri, 12 Apr 2024 05:07:29 +0000 (-0400) Subject: bdev: infrastructure for flags X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=1116b9fa15c09748ae05d2365a305fa22671eb1e;p=linux.git bdev: infrastructure for flags Replace bd_partno with a 32bit field (__bd_flags). The lower 8 bits contain the partition number, the upper 24 are for flags. Helpers: bdev_{test,set,clear}_flag(bdev, flag), with atomic_or() and atomic_andnot() used to set/clear. NOTE: this commit does not actually move any flags over there - they are still bool fields. As the result, it shifts the fields wrt cacheline boundaries; that's going to be restored once the first 3 flags are dealt with. Signed-off-by: Al Viro --- diff --git a/block/bdev.c b/block/bdev.c index 7a5f611c3d2e3..2ec223315500e 100644 --- a/block/bdev.c +++ b/block/bdev.c @@ -411,7 +411,7 @@ struct block_device *bdev_alloc(struct gendisk *disk, u8 partno) mutex_init(&bdev->bd_fsfreeze_mutex); spin_lock_init(&bdev->bd_size_lock); mutex_init(&bdev->bd_holder_lock); - bdev->bd_partno = partno; + atomic_set(&bdev->__bd_flags, partno); bdev->bd_inode = inode; bdev->bd_queue = disk->queue; if (partno) diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h index cb1526ec44b5f..04f92737ab08a 100644 --- a/include/linux/blk_types.h +++ b/include/linux/blk_types.h @@ -45,8 +45,9 @@ struct block_device { struct request_queue * bd_queue; struct disk_stats __percpu *bd_stats; unsigned long bd_stamp; + atomic_t __bd_flags; // partition number + flags +#define BD_PARTNO 255 // lower 8 bits; assign-once bool bd_read_only; /* read-only policy */ - u8 bd_partno; bool bd_write_holder; bool bd_has_submit_bio; dev_t bd_dev; diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 32549d6759557..99917e5860fd2 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -722,7 +722,22 @@ void disk_uevent(struct gendisk *disk, enum kobject_action action); static inline u8 bdev_partno(const struct block_device *bdev) { - return bdev->bd_partno; + return atomic_read(&bdev->__bd_flags) & BD_PARTNO; +} + +static inline bool bdev_test_flag(const struct block_device *bdev, unsigned flag) +{ + return atomic_read(&bdev->__bd_flags) & flag; +} + +static inline void bdev_set_flag(struct block_device *bdev, unsigned flag) +{ + atomic_or(flag, &bdev->__bd_flags); +} + +static inline void bdev_clear_flag(struct block_device *bdev, unsigned flag) +{ + atomic_andnot(flag, &bdev->__bd_flags); } static inline int get_disk_ro(struct gendisk *disk)