From fa06052d637bf3a76f18cd2304048b866af4096e Mon Sep 17 00:00:00 2001 From: Jan Kara Date: Wed, 12 Apr 2017 12:24:37 +0200 Subject: [PATCH] mtd: Convert to dynamically allocated bdi infrastructure MTD already allocates backing_dev_info dynamically. Convert it to use generic infrastructure for this including proper refcounting. We drop mtd->backing_dev_info as its only use was to pass mtd_bdi pointer from one file into another and if we wanted to keep that in a clean way, we'd have to make mtd hold and drop bdi reference as needed which seems pointless for passing one global pointer... CC: David Woodhouse CC: Brian Norris CC: linux-mtd@lists.infradead.org Reviewed-by: Christoph Hellwig Signed-off-by: Jan Kara Signed-off-by: Jens Axboe --- drivers/mtd/mtdcore.c | 23 ++++++++++++----------- drivers/mtd/mtdsuper.c | 7 ++++++- include/linux/mtd/mtd.h | 5 ----- 3 files changed, 18 insertions(+), 17 deletions(-) diff --git a/drivers/mtd/mtdcore.c b/drivers/mtd/mtdcore.c index 66a9dedd1062..23e2e56ca54e 100644 --- a/drivers/mtd/mtdcore.c +++ b/drivers/mtd/mtdcore.c @@ -46,7 +46,7 @@ #include "mtdcore.h" -static struct backing_dev_info *mtd_bdi; +struct backing_dev_info *mtd_bdi; #ifdef CONFIG_PM_SLEEP @@ -496,11 +496,9 @@ int add_mtd_device(struct mtd_info *mtd) * mtd_device_parse_register() multiple times on the same master MTD, * especially with CONFIG_MTD_PARTITIONED_MASTER=y. */ - if (WARN_ONCE(mtd->backing_dev_info, "MTD already registered\n")) + if (WARN_ONCE(mtd->dev.type, "MTD already registered\n")) return -EEXIST; - mtd->backing_dev_info = mtd_bdi; - BUG_ON(mtd->writesize == 0); mutex_lock(&mtd_table_mutex); @@ -1775,13 +1773,18 @@ static struct backing_dev_info * __init mtd_bdi_init(char *name) struct backing_dev_info *bdi; int ret; - bdi = kzalloc(sizeof(*bdi), GFP_KERNEL); + bdi = bdi_alloc(GFP_KERNEL); if (!bdi) return ERR_PTR(-ENOMEM); - ret = bdi_setup_and_register(bdi, name); + bdi->name = name; + /* + * We put '-0' suffix to the name to get the same name format as we + * used to get. Since this is called only once, we get a unique name. + */ + ret = bdi_register(bdi, NULL, "%.28s-0", name); if (ret) - kfree(bdi); + bdi_put(bdi); return ret ? ERR_PTR(ret) : bdi; } @@ -1813,8 +1816,7 @@ static int __init init_mtd(void) out_procfs: if (proc_mtd) remove_proc_entry("mtd", NULL); - bdi_destroy(mtd_bdi); - kfree(mtd_bdi); + bdi_put(mtd_bdi); err_bdi: class_unregister(&mtd_class); err_reg: @@ -1828,8 +1830,7 @@ static void __exit cleanup_mtd(void) if (proc_mtd) remove_proc_entry("mtd", NULL); class_unregister(&mtd_class); - bdi_destroy(mtd_bdi); - kfree(mtd_bdi); + bdi_put(mtd_bdi); idr_destroy(&mtd_idr); } diff --git a/drivers/mtd/mtdsuper.c b/drivers/mtd/mtdsuper.c index 20c02a3b7417..e69e7855e31f 100644 --- a/drivers/mtd/mtdsuper.c +++ b/drivers/mtd/mtdsuper.c @@ -18,6 +18,7 @@ #include #include #include +#include /* * compare superblocks to see if they're equivalent @@ -38,6 +39,8 @@ static int get_sb_mtd_compare(struct super_block *sb, void *_mtd) return 0; } +extern struct backing_dev_info *mtd_bdi; + /* * mark the superblock by the MTD device it is using * - set the device number to be the correct MTD block device for pesuperstence @@ -49,7 +52,9 @@ static int get_sb_mtd_set(struct super_block *sb, void *_mtd) sb->s_mtd = mtd; sb->s_dev = MKDEV(MTD_BLOCK_MAJOR, mtd->index); - sb->s_bdi = mtd->backing_dev_info; + sb->s_bdi = bdi_get(mtd_bdi); + sb->s_iflags |= SB_I_DYNBDI; + return 0; } diff --git a/include/linux/mtd/mtd.h b/include/linux/mtd/mtd.h index eebdc63cf6af..79b176eca04a 100644 --- a/include/linux/mtd/mtd.h +++ b/include/linux/mtd/mtd.h @@ -334,11 +334,6 @@ struct mtd_info { int (*_get_device) (struct mtd_info *mtd); void (*_put_device) (struct mtd_info *mtd); - /* Backing device capabilities for this device - * - provides mmap capabilities - */ - struct backing_dev_info *backing_dev_info; - struct notifier_block reboot_notifier; /* default mode before reboot */ /* ECC status information */