From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Matthew Wilcox To: linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Matthew Wilcox , Jan Kara , Jeff Layton , Lukas Czerner , Ross Zwisler , Christoph Hellwig , Goldwyn Rodrigues , Nicholas Piggin , Ryusuke Konishi , linux-nilfs@vger.kernel.org, Jaegeuk Kim , Chao Yu , linux-f2fs-devel@lists.sourceforge.net Subject: [PATCH v14 15/74] xarray: Destroy an XArray Date: Sat, 16 Jun 2018 18:59:53 -0700 Message-Id: <20180617020052.4759-16-willy@infradead.org> In-Reply-To: <20180617020052.4759-1-willy@infradead.org> References: <20180617020052.4759-1-willy@infradead.org> Sender: owner-linux-mm@kvack.org List-ID: This function frees all the internal memory allocated to the xarray and reinitialises it to be empty. Signed-off-by: Matthew Wilcox --- include/linux/xarray.h | 1 + lib/xarray.c | 28 ++++++++++++++++++++++++++++ 2 files changed, 29 insertions(+) diff --git a/include/linux/xarray.h b/include/linux/xarray.h index 6f398732b664..fa36a0670988 100644 --- a/include/linux/xarray.h +++ b/include/linux/xarray.h @@ -229,6 +229,7 @@ void *xa_find_after(struct xarray *xa, unsigned long *index, unsigned long max, xa_tag_t) __attribute__((nonnull(2))); unsigned int xa_extract(struct xarray *, void **dst, unsigned long start, unsigned long max, unsigned int n, xa_tag_t); +void xa_destroy(struct xarray *); /** * xa_init() - Initialise an empty XArray. diff --git a/lib/xarray.c b/lib/xarray.c index 1e15ead40d78..e90ba76404ae 100644 --- a/lib/xarray.c +++ b/lib/xarray.c @@ -1493,6 +1493,34 @@ unsigned int xa_extract(struct xarray *xa, void **dst, unsigned long start, } EXPORT_SYMBOL(xa_extract); +/** + * xa_destroy() - Free all internal data structures. + * @xa: XArray. + * + * After calling this function, the XArray is empty and has freed all memory + * allocated for its internal data structures. You are responsible for + * freeing the objects referenced by the XArray. + * + * Context: Any context. Takes and releases the xa_lock, interrupt-safe. + */ +void xa_destroy(struct xarray *xa) +{ + XA_STATE(xas, xa, 0); + unsigned long flags; + void *entry; + + xas.xa_node = NULL; + xas_lock_irqsave(&xas, flags); + entry = xa_head_locked(xa); + RCU_INIT_POINTER(xa->xa_head, NULL); + xas_init_tags(&xas); + /* lockdep checks we're still holding the lock in xas_free_nodes() */ + if (xa_is_node(entry)) + xas_free_nodes(&xas, xa_to_node(entry)); + xas_unlock_irqrestore(&xas, flags); +} +EXPORT_SYMBOL(xa_destroy); + #ifdef XA_DEBUG void xa_dump_node(const struct xa_node *node) { -- 2.17.1