Unverified Commit 538f4f02 authored by Christian Brauner's avatar Christian Brauner
Browse files

fs: add kernel doc for mnt_{hold,unhold}_writers() 

When I introduced mnt_{hold,unhold}_writers() in commit fbdc2f6c
("fs: split out functions to hold writers") I did not add kernel doc for
them. Fix this and introduce proper documentation.

Link: https://lore.kernel.org/r/20220203131411.3093040-4-brauner@kernel.org


Fixes: fbdc2f6c ("fs: split out functions to hold writers")
Cc: Seth Forshee <seth.forshee@digitalocean.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
Signed-off-by: default avatarChristian Brauner <brauner@kernel.org>
parent 97acd701

fs/namespace.c

+30 −0
Original line number Diff line number Diff line
@@ -469,6 +469,24 @@ void mnt_drop_write_file(struct file *file) 
}

EXPORT_SYMBOL(mnt_drop_write_file);



/**

 * mnt_hold_writers - prevent write access to the given mount

 * @mnt: mnt to prevent write access to

 *

 * Prevents write access to @mnt if there are no active writers for @mnt.

 * This function needs to be called and return successfully before changing

 * properties of @mnt that need to remain stable for callers with write access

 * to @mnt.

 *

 * After this functions has been called successfully callers must pair it with

 * a call to mnt_unhold_writers() in order to stop preventing write access to

 * @mnt.

 *

 * Context: This function expects lock_mount_hash() to be held serializing

 *          setting MNT_WRITE_HOLD.

 * Return: On success 0 is returned.

 *	   On error, -EBUSY is returned.

 */

static inline int mnt_hold_writers(struct mount *mnt)

{

	mnt->mnt.mnt_flags |= MNT_WRITE_HOLD;
@@ -500,6 +518,18 @@ static inline int mnt_hold_writers(struct mount *mnt) 
	return 0;

}



/**

 * mnt_unhold_writers - stop preventing write access to the given mount

 * @mnt: mnt to stop preventing write access to

 *

 * Stop preventing write access to @mnt allowing callers to gain write access

 * to @mnt again.

 *

 * This function can only be called after a successful call to

 * mnt_hold_writers().

 *

 * Context: This function expects lock_mount_hash() to be held.

 */

static inline void mnt_unhold_writers(struct mount *mnt)

{

	/*