From mboxrd@z Thu Jan 1 00:00:00 1970 From: bugzilla-daemon@bugzilla.kernel.org Subject: [Bug 196405] mkdir mishandles st_nlink in ext4 directory with 64997 subdirectories Date: Tue, 18 Jul 2017 21:54:52 +0000 Message-ID: References: Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8BIT To: linux-ext4@kernel.org Return-path: Received: from mail.wl.linuxfoundation.org ([198.145.29.98]:38656 "EHLO mail.wl.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752191AbdGRVy7 (ORCPT ); Tue, 18 Jul 2017 17:54:59 -0400 Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 2C070285C2 for ; Tue, 18 Jul 2017 21:54:59 +0000 (UTC) In-Reply-To: Sender: linux-ext4-owner@vger.kernel.org List-ID: https://bugzilla.kernel.org/show_bug.cgi?id=196405 --- Comment #4 from Andreas Dilger (adilger.kernelbugzilla@dilger.ca) --- The limit is implemented as < 65000, which was somewhat below the hard limit of the ext4_inode.i_links_count __u16 field of 65535. There is no hard reason for 65000 except to allow some margin for detecting overflow, and reserved values if there was a need. I don't think it makes a big practical difference whether directory link counts are accurate up to 65000 or 65534 subdirectories, since very few systems have this many subdirectories. In theory, we could add an i_links_count_hi field to extend this to a 32-bit value, but it isn't clear if there is a big benefit from doing this? -- You are receiving this mail because: You are watching the assignee of the bug.