From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pg0-f72.google.com (mail-pg0-f72.google.com [74.125.83.72]) by kanga.kvack.org (Postfix) with ESMTP id 6A0406B002A for ; Tue, 13 Mar 2018 09:26:53 -0400 (EDT) Received: by mail-pg0-f72.google.com with SMTP id q2so8115719pgn.22 for ; Tue, 13 Mar 2018 06:26:53 -0700 (PDT) Received: from bombadil.infradead.org (bombadil.infradead.org. [2607:7c80:54:e::133]) by mx.google.com with ESMTPS id x18-v6si145583pln.194.2018.03.13.06.26.51 for (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Tue, 13 Mar 2018 06:26:51 -0700 (PDT) From: Matthew Wilcox Subject: [PATCH v9 20/61] xarray: Add xa_destroy Date: Tue, 13 Mar 2018 06:25:58 -0700 Message-Id: <20180313132639.17387-21-willy@infradead.org> In-Reply-To: <20180313132639.17387-1-willy@infradead.org> References: <20180313132639.17387-1-willy@infradead.org> Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton Cc: Matthew Wilcox , linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, Ryusuke Konishi , linux-nilfs@vger.kernel.org From: Matthew Wilcox 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 85dd909586f0..96773f83ae03 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 124bbfec66ae..080ed0fc3feb 100644 --- a/lib/xarray.c +++ b/lib/xarray.c @@ -1468,6 +1468,34 @@ 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) { -- 2.16.1