On 2017/5/10 上午1:56, Eric Wheeler wrote: > On Tue, 9 May 2017, Coly Li wrote: > >> On 2017/5/9 下午2:25, tang.junhui@xxxxxxxxxx wrote: >>> From: "tang.junhui" <tang.junhui@xxxxxxxxxx> >>> >>> bcache called ida_simple_remove() with minor which have multiplied by >>> BCACHE_MINORS, it would cause minor wrong release and leakage >>> >>> Signed-off-by: tang.junhui <tang.junhui@xxxxxxxxxx> >> >> Reviewed-by: Coly Li <colyli@xxxxxxx> >> >> Hi Eric: >> >> You are the original author of bcache partition support, I also include >> you, would you like to push this patch upstream ? >> >> Thanks. > > Well, to be certain, this was the original motivation for the patch so Sam > Yaple should get the credit: https://yaple.net/2016/03/31/bcache-partitions-and-dkms/ > Sure, thanks to Sam Yaple! > But, to answer your question: Yes, I'll put together a pull. There are > quite a few patches that need caught up on other points as well. Thank you again, for pushing them upstream :-) Coly >>> --- >>> drivers/md/bcache/super.c | 16 +++++++++------- >>> 1 file changed, 9 insertions(+), 7 deletions(-) >>> >>> diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c >>> index 867d9a9..5723914 100644 >>> --- a/drivers/md/bcache/super.c >>> +++ b/drivers/md/bcache/super.c >>> @@ -57,8 +57,11 @@ static DEFINE_IDA(bcache_minor); >>> static wait_queue_head_t unregister_wait; >>> struct workqueue_struct *bcache_wq; >>> >>> -#define BTREE_MAX_PAGES (256 * 1024 / PAGE_SIZE) >>> -#define BCACHE_MINORS 16 /* partition support */ >>> +#define BTREE_MAX_PAGES (256 * 1024 / PAGE_SIZE) >>> +#define BCACHE_MINORS_BITS 4 /* bcache partition support */ >>> +#define BCACHE_MINORS (1 << BCACHE_MINORS_BITS) >>> +#define BCACHE_TO_IDA_MINORS(first_minor) ((first_minor) >> BCACHE_MINORS_BITS) >>> +#define IDA_TO_BCACHE_MINORS(minor) ((minor) << BCACHE_MINORS_BITS) >>> >>> /* Superblock */ >>> >>> @@ -734,7 +737,7 @@ static void bcache_device_free(struct bcache_device *d) >>> if (d->disk && d->disk->queue) >>> blk_cleanup_queue(d->disk->queue); >>> if (d->disk) { >>> - ida_simple_remove(&bcache_minor, d->disk->first_minor); >>> + ida_simple_remove(&bcache_minor, BCACHE_TO_IDA_MINORS(d->disk->first_minor)); >>> put_disk(d->disk); >>> } >>> >>> @@ -780,11 +783,10 @@ static int bcache_device_init(struct bcache_device *d, unsigned block_size, >>> if (!d->full_dirty_stripes) >>> return -ENOMEM; >>> >>> - minor = ida_simple_get(&bcache_minor, 0, MINORMASK + 1, GFP_KERNEL); >>> + minor = ida_simple_get(&bcache_minor, 0, BCACHE_TO_IDA_MONIRS(MINORMASK) + 1, GFP_KERNEL); >>> if (minor < 0) >>> return minor; >>> >>> - minor *= BCACHE_MINORS; >>> >>> if (!(d->bio_split = bioset_create(4, offsetof(struct bbio, bio))) || >>> !(d->disk = alloc_disk(BCACHE_MINORS))) { >>> @@ -793,10 +795,10 @@ static int bcache_device_init(struct bcache_device *d, unsigned block_size, >>> } >>> >>> set_capacity(d->disk, sectors); >>> - snprintf(d->disk->disk_name, DISK_NAME_LEN, "bcache%i", minor / BCACHE_MINORS); >>> + snprintf(d->disk->disk_name, DISK_NAME_LEN, "bcache%i", minor); >>> >>> d->disk->major = bcache_major; >>> - d->disk->first_minor = minor; >>> + d->disk->first_minor = IDA_TO_BCACHE_MINORS(minor); >>> d->disk->fops = &bcache_ops; >>> d->disk->private_data = d; >>> -- To unsubscribe from this list: send the line "unsubscribe linux-bcache" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
