From 5f4eee5fc938a655710c18a9997dc5d780e46673 Mon Sep 17 00:00:00 2001
From: Gleb Chesnokov <gleb.chesnokov@scst.dev>
Date: Mon, 8 Jul 2024 11:31:11 +0300
Subject: [PATCH] scst_lib: use bdev_nr_bytes(bdev) instead of
 i_size_read(bdev->bd_inode)

Use the helper to query the size of a block device in bytes.
---
 scst/include/backport.h | 12 ++++++++++++
 scst/src/scst_lib.c     |  2 +-
 2 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/scst/include/backport.h b/scst/include/backport.h
index c54027707..7967508ef 100644
--- a/scst/include/backport.h
+++ b/scst/include/backport.h
@@ -329,6 +329,18 @@ static inline void bdev_release_backport(struct bdev_handle *handle)
 
 #endif
 
+#if LINUX_VERSION_CODE < KERNEL_VERSION(5, 16, 0)
+/*
+ * See also commit 6436bd90f76e ("block: add a bdev_nr_bytes helper") # v5.16.
+ */
+static inline loff_t bdev_nr_bytes_backport(struct block_device *bdev)
+{
+	return i_size_read(bdev->bd_inode);
+}
+
+#define bdev_nr_bytes bdev_nr_bytes_backport
+#endif
+
 #if LINUX_VERSION_CODE < KERNEL_VERSION(5, 19, 0) &&		\
 	(!defined(RHEL_RELEASE_CODE) ||				\
 	 RHEL_RELEASE_CODE -0 < RHEL_RELEASE_VERSION(9, 1))
diff --git a/scst/src/scst_lib.c b/scst/src/scst_lib.c
index 88239217e..ba776beac 100644
--- a/scst/src/scst_lib.c
+++ b/scst/src/scst_lib.c
@@ -6178,7 +6178,7 @@ loff_t scst_bdev_size(const char *path)
 	if (rc)
 		return rc;
 
-	res = i_size_read(bdev_desc.bdev->bd_inode);
+	res = bdev_nr_bytes(bdev_desc.bdev);
 
 	scst_release_bdev(&bdev_desc);
 	return res;