From 28144f9998e047a9bac31421914335c6bc6eaa67 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Thu, 29 Oct 2020 15:58:34 +0100 Subject: [PATCH] md: use __register_blkdev to allocate devices on demand 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 Reviewed-by: Hannes Reinecke Acked-by: Song Liu Signed-off-by: Jens Axboe --- 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 96d3133..3c79243 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<