From patchwork Tue Nov 1 19:54:13 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ross Zwisler X-Patchwork-Id: 9407937 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id E6BA960721 for ; Tue, 1 Nov 2016 19:59:21 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id D79B928C78 for ; Tue, 1 Nov 2016 19:59:21 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id CA6E129A8A; Tue, 1 Nov 2016 19:59:21 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 4397A28C78 for ; Tue, 1 Nov 2016 19:59:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754416AbcKATyh (ORCPT ); Tue, 1 Nov 2016 15:54:37 -0400 Received: from mga11.intel.com ([192.55.52.93]:56133 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754321AbcKATyf (ORCPT ); Tue, 1 Nov 2016 15:54:35 -0400 Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by fmsmga102.fm.intel.com with ESMTP; 01 Nov 2016 12:54:35 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.31,433,1473145200"; d="scan'208";a="186453117" Received: from theros.lm.intel.com ([10.232.112.77]) by fmsmga004.fm.intel.com with ESMTP; 01 Nov 2016 12:54:32 -0700 From: Ross Zwisler To: linux-kernel@vger.kernel.org Cc: Ross Zwisler , "Theodore Ts'o" , Alexander Viro , Andreas Dilger , Andrew Morton , Christoph Hellwig , Dan Williams , Dave Chinner , Jan Kara , Matthew Wilcox , linux-ext4@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-nvdimm@lists.01.org, linux-xfs@vger.kernel.org Subject: [PATCH v9 11/16] dax: dax_iomap_fault() needs to call iomap_end() Date: Tue, 1 Nov 2016 13:54:13 -0600 Message-Id: <1478030058-1422-12-git-send-email-ross.zwisler@linux.intel.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1478030058-1422-1-git-send-email-ross.zwisler@linux.intel.com> References: <1478030058-1422-1-git-send-email-ross.zwisler@linux.intel.com> Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Currently iomap_end() doesn't do anything for DAX page faults for both ext2 and XFS. ext2_iomap_end() just checks for a write underrun, and xfs_file_iomap_end() checks to see if it needs to finish a delayed allocation. However, in the future iomap_end() calls might be needed to make sure we have balanced allocations, locks, etc. So, add calls to iomap_end() with appropriate error handling to dax_iomap_fault(). Signed-off-by: Ross Zwisler Suggested-by: Jan Kara Reviewed-by: Jan Kara --- fs/dax.c | 37 +++++++++++++++++++++++++++++-------- 1 file changed, 29 insertions(+), 8 deletions(-) diff --git a/fs/dax.c b/fs/dax.c index 7737954..6edd89b 100644 --- a/fs/dax.c +++ b/fs/dax.c @@ -1165,6 +1165,7 @@ int dax_iomap_fault(struct vm_area_struct *vma, struct vm_fault *vmf, struct iomap iomap = { 0 }; unsigned flags = 0; int error, major = 0; + int locked_status = 0; void *entry; /* @@ -1194,7 +1195,7 @@ int dax_iomap_fault(struct vm_area_struct *vma, struct vm_fault *vmf, goto unlock_entry; if (WARN_ON_ONCE(iomap.offset + iomap.length < pos + PAGE_SIZE)) { error = -EIO; /* fs corruption? */ - goto unlock_entry; + goto finish_iomap; } sector = dax_iomap_sector(&iomap, pos); @@ -1216,13 +1217,15 @@ int dax_iomap_fault(struct vm_area_struct *vma, struct vm_fault *vmf, } if (error) - goto unlock_entry; + goto finish_iomap; if (!radix_tree_exceptional_entry(entry)) { vmf->page = entry; - return VM_FAULT_LOCKED; + locked_status = VM_FAULT_LOCKED; + } else { + vmf->entry = entry; + locked_status = VM_FAULT_DAX_LOCKED; } - vmf->entry = entry; - return VM_FAULT_DAX_LOCKED; + goto finish_iomap; } switch (iomap.type) { @@ -1237,8 +1240,10 @@ int dax_iomap_fault(struct vm_area_struct *vma, struct vm_fault *vmf, break; case IOMAP_UNWRITTEN: case IOMAP_HOLE: - if (!(vmf->flags & FAULT_FLAG_WRITE)) - return dax_load_hole(mapping, entry, vmf); + if (!(vmf->flags & FAULT_FLAG_WRITE)) { + locked_status = dax_load_hole(mapping, entry, vmf); + break; + } /*FALLTHRU*/ default: WARN_ON_ONCE(1); @@ -1246,14 +1251,30 @@ int dax_iomap_fault(struct vm_area_struct *vma, struct vm_fault *vmf, break; } + finish_iomap: + if (ops->iomap_end) { + if (error) { + /* keep previous error */ + ops->iomap_end(inode, pos, PAGE_SIZE, 0, flags, + &iomap); + } else { + error = ops->iomap_end(inode, pos, PAGE_SIZE, + PAGE_SIZE, flags, &iomap); + } + } unlock_entry: - put_locked_mapping_entry(mapping, vmf->pgoff, entry); + if (!locked_status || error) + put_locked_mapping_entry(mapping, vmf->pgoff, entry); out: if (error == -ENOMEM) return VM_FAULT_OOM | major; /* -EBUSY is fine, somebody else faulted on the same PTE */ if (error < 0 && error != -EBUSY) return VM_FAULT_SIGBUS | major; + if (locked_status) { + WARN_ON_ONCE(error); /* -EBUSY from ops->iomap_end? */ + return locked_status; + } return VM_FAULT_NOPAGE | major; } EXPORT_SYMBOL_GPL(dax_iomap_fault);