From: "Kirill A. Shutemov" Subject: [PATCHv1, RFC 06/33] radix-tree: Handle multiorder entries being deleted by replace_clear_tags Date: Tue, 26 Jul 2016 03:35:08 +0300 Message-ID: <1469493335-3622-7-git-send-email-kirill.shutemov@linux.intel.com> References: <1469493335-3622-1-git-send-email-kirill.shutemov@linux.intel.com> Cc: Alexander Viro , Hugh Dickins , Andrea Arcangeli , Andrew Morton , Dave Hansen , Vlastimil Babka , Matthew Wilcox , Ross Zwisler , linux-ext4@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-block@vger.kernel.org, "Kirill A . Shutemov" To: "Theodore Ts'o" , Andreas Dilger , Jan Kara Return-path: In-Reply-To: <1469493335-3622-1-git-send-email-kirill.shutemov@linux.intel.com> Sender: owner-linux-mm@kvack.org List-Id: linux-ext4.vger.kernel.org From: Matthew Wilcox radix_tree_replace_clear_tags() can be called with NULL as the replacement value; in this case we need to delete sibling entries which point to the slot. Signed-off-by: Matthew Wilcox Signed-off-by: Kirill A. Shutemov --- lib/radix-tree.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/lib/radix-tree.c b/lib/radix-tree.c index e49f32f7c537..89092c4011b8 100644 --- a/lib/radix-tree.c +++ b/lib/radix-tree.c @@ -1799,17 +1799,23 @@ void *radix_tree_delete(struct radix_tree_root *root, unsigned long index) } EXPORT_SYMBOL(radix_tree_delete); +/* + * If the caller passes NULL for @entry, it must take care to adjust + * node->count. See page_cache_tree_delete() for an example. + */ struct radix_tree_node *radix_tree_replace_clear_tags( struct radix_tree_root *root, unsigned long index, void *entry) { struct radix_tree_node *node; void **slot; + unsigned int offset; __radix_tree_lookup(root, index, &node, &slot); if (node) { - unsigned int tag, offset = get_slot_offset(node, slot); + unsigned int tag; + offset = get_slot_offset(node, slot); for (tag = 0; tag < RADIX_TREE_MAX_TAGS; tag++) node_tag_clear(root, node, tag, offset); } else { @@ -1818,6 +1824,9 @@ struct radix_tree_node *radix_tree_replace_clear_tags( } radix_tree_replace_slot(slot, entry); + if (!entry && node) + delete_sibling_entries(node, node_to_entry(slot), offset); + return node; } -- 2.8.1 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org