From: Xie Yongji <xieyongji@bytedance.com>
Date: Tue, 26 Oct 2021 14:40:12 +0000 (+0800)
Subject: block: Add a helper to validate the block size
X-Git-Tag: v4.14.276~274
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=cb55a760a24b1458e856141c43922e88bd1fbcd8;p=thirdparty%2Fkernel%2Fstable.git

block: Add a helper to validate the block size

commit 570b1cac477643cbf01a45fa5d018430a1fddbce upstream.

There are some duplicated codes to validate the block
size in block drivers. This limitation actually comes
from block layer, so this patch tries to add a new block
layer helper for that.

Signed-off-by: Xie Yongji <xieyongji@bytedance.com>
Link: https://lore.kernel.org/r/20211026144015.188-2-xieyongji@bytedance.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 1c3d774d3c839..afbe2fcc476ac 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -56,6 +56,14 @@ struct blk_stat_callback;
  */
 #define BLKCG_MAX_POLS		3
 
+static inline int blk_validate_block_size(unsigned int bsize)
+{
+	if (bsize < 512 || bsize > PAGE_SIZE || !is_power_of_2(bsize))
+		return -EINVAL;
+
+	return 0;
+}
+
 typedef void (rq_end_io_fn)(struct request *, blk_status_t);
 
 #define BLK_RL_SYNCFULL		(1U << 0)