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From: "Matthew Wilcox (Oracle)" <willy@infradead.org>
To: Jonathan Corbet <corbet@lwn.net>
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>,
	linux-doc@vger.kernel.org,
	linux-fsdevel@vger.kernel.org,
	linux-kernel@vger.kernel.org
Subject: [PATCH v2 7/8] buffer: Improve bdev_getblk documentation
Date: Tue,  9 Jan 2024 14:33:56 +0000
Message-Id: <20240109143357.2375046-8-willy@infradead.org>
In-Reply-To: <20240109143357.2375046-1-willy@infradead.org>
References: <20240109143357.2375046-1-willy@infradead.org>
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Add some more information about the state of the buffer_head returned.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
---
 fs/buffer.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/fs/buffer.c b/fs/buffer.c
index 05b68eccfdcc..562de7e013f7 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -1424,6 +1424,11 @@ EXPORT_SYMBOL(__find_get_block);
  * @size: The size of buffer_heads for this @bdev.
  * @gfp: The memory allocation flags to use.
  *
+ * The returned buffer head has its reference count incremented, but is
+ * not locked.  The caller should call brelse() when it has finished
+ * with the buffer.  The buffer may not be uptodate.  If needed, the
+ * caller can bring it uptodate either by reading it or overwriting it.
+ *
  * Return: The buffer head, or NULL if memory could not be allocated.
  */
 struct buffer_head *bdev_getblk(struct block_device *bdev, sector_t block,
-- 
2.43.0