[PATCH 11/18] md: use __register_blkdev to allocate devices on demand
From: Christoph Hellwig <hch@lst.de>
Date: 2020-10-29 15:25:57
Also in:
linux-block, linux-ide, linux-m68k, linux-scsi, lkml
Subsystem:
software raid (multiple disks) support, the rest · Maintainers:
Song Liu, Yu Kuai, Linus Torvalds
Use the simpler mechanism attached to major_name to allocate a md device when a currently unregistered minor is accessed. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Song Liu <song@kernel.org> Reviewed-by: Hannes Reinecke <hare@suse.de> --- drivers/md/md.c | 21 ++++++++------------- 1 file changed, 8 insertions(+), 13 deletions(-)
diff --git a/drivers/md/md.c b/drivers/md/md.c
index 98bac4f304ae26..2268bd92a2267b 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c@@ -5765,11 +5765,12 @@ static int md_alloc(dev_t dev, char *name) return error; } -static struct kobject *md_probe(dev_t dev, int *part, void *data) +static void md_probe(dev_t dev) { + if (MAJOR(dev) == MD_MAJOR && MINOR(dev) >= 512) + return; if (create_on_open) md_alloc(dev, NULL); - return NULL; } static int add_named_array(const char *val, const struct kernel_param *kp)
@@ -6535,7 +6536,7 @@ static void autorun_devices(int part) break; } - md_probe(dev, NULL, NULL); + md_probe(dev); mddev = mddev_find(dev); if (!mddev || !mddev->gendisk) { if (mddev)
@@ -9567,18 +9568,15 @@ static int __init md_init(void) if (!md_rdev_misc_wq) goto err_rdev_misc_wq; - if ((ret = register_blkdev(MD_MAJOR, "md")) < 0) + ret = __register_blkdev(MD_MAJOR, "md", md_probe); + if (ret < 0) goto err_md; - if ((ret = register_blkdev(0, "mdp")) < 0) + ret = __register_blkdev(0, "mdp", md_probe); + if (ret < 0) goto err_mdp; mdp_major = ret; - blk_register_region(MKDEV(MD_MAJOR, 0), 512, THIS_MODULE, - md_probe, NULL, NULL); - blk_register_region(MKDEV(mdp_major, 0), 1UL<<MINORBITS, THIS_MODULE, - md_probe, NULL, NULL); - register_reboot_notifier(&md_notifier); raid_table_header = register_sysctl_table(raid_root_table);
@@ -9845,9 +9843,6 @@ static __exit void md_exit(void) struct list_head *tmp; int delay = 1; - blk_unregister_region(MKDEV(MD_MAJOR,0), 512); - blk_unregister_region(MKDEV(mdp_major,0), 1U << MINORBITS); - unregister_blkdev(MD_MAJOR,"md"); unregister_blkdev(mdp_major, "mdp"); unregister_reboot_notifier(&md_notifier);
--
2.28.0