From:   Tadeusz Struk <tadeusz.struk@linaro.org>
To:     stable@vger.kernel.org
Cc:     tadeusz.struk@linaro.org, axboe@kernel.dk, hch@lst.de,
        linux-block@vger.kernel.org, linux-kernel@vger.kernel.org,
        syzbot+662448179365dddc1880@syzkaller.appspotmail.com,
        xieyongji@bytedance.com
Subject: [PATCH 5.15] block: Add a helper to validate the block size
Date:   Thu, 18 Nov 2021 15:57:38 -0800
Message-Id: <20211118235738.1128085-1-tadeusz.struk@linaro.org>
In-Reply-To: <7e6c4c23-f071-f33b-7bd4-da11980d34c6@linaro.org>
References: <7e6c4c23-f071-f33b-7bd4-da11980d34c6@linaro.org>
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From: Xie Yongji <xieyongji@bytedance.com>

From: Xie Yongji <xieyongji@bytedance.com>

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: Tadeusz Struk <tadeusz.struk@linaro.org>
---
 include/linux/blkdev.h | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 683aee365420..5b03795ae33b 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -54,6 +54,14 @@ struct blk_keyslot_manager;
  */
 #define BLKCG_MAX_POLS		6
 
+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);
 
 /*
-- 
2.33.1