diff options
author | Christian Brauner <brauner@kernel.org> | 2022-02-03 14:14:07 +0100 |
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committer | Christian Brauner <brauner@kernel.org> | 2022-02-14 08:35:32 +0100 |
commit | 538f4f022a4612f969d5324ee227403c9f8b1d72 (patch) | |
tree | 24cc403cda6118284ef57618944efefeab45dafe /fs/namespace.c | |
parent | 97acd701185b13825f8ec7882345040415d46762 (diff) | |
download | linux-538f4f022a4612f969d5324ee227403c9f8b1d72.tar.bz2 |
fs: add kernel doc for mnt_{hold,unhold}_writers()
When I introduced mnt_{hold,unhold}_writers() in commit fbdc2f6c40f6
("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: fbdc2f6c40f6 ("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: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Diffstat (limited to 'fs/namespace.c')
-rw-r--r-- | fs/namespace.c | 30 |
1 files changed, 30 insertions, 0 deletions
diff --git a/fs/namespace.c b/fs/namespace.c index 40b994a29e90..de6fae84f1a1 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -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) { /* |