From: Matthew Wilcox Subject: [PATCH v2 3/6] ext4: Use ext4_get_block_write() for DAX Date: Fri, 3 Jul 2015 10:40:40 -0400 Message-ID: <1435934443-17090-4-git-send-email-matthew.r.wilcox@intel.com> References: <1435934443-17090-1-git-send-email-matthew.r.wilcox@intel.com> Cc: Matthew Wilcox , "Theodore Ts'o" , Andreas Dilger , linux-ext4@vger.kernel.org To: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, Alexander Viro Return-path: In-Reply-To: <1435934443-17090-1-git-send-email-matthew.r.wilcox@intel.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-ext4.vger.kernel.org From: Matthew Wilcox DAX relies on the get_block function either zeroing newly allocated blocks before they're findable by subsequent calls to get_block, or marking newly allocated blocks as unwritten. ext4_get_block() cannot create unwritten extents, but ext4_get_block_write() can. Reported-by: Andy Rudoff Signed-off-by: Matthew Wilcox --- fs/ext4/file.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/fs/ext4/file.c b/fs/ext4/file.c index bc313ac..e5bdcb7 100644 --- a/fs/ext4/file.c +++ b/fs/ext4/file.c @@ -195,7 +195,7 @@ out: static void ext4_end_io_unwritten(struct buffer_head *bh, int uptodate) { struct inode *inode = bh->b_assoc_map->host; - /* XXX: breaks on 32-bit > 16GB. Is that even supported? */ + /* XXX: breaks on 32-bit > 16TB. Is that even supported? */ loff_t offset = (loff_t)(uintptr_t)bh->b_private << inode->i_blkbits; int err; if (!uptodate) @@ -206,13 +206,13 @@ static void ext4_end_io_unwritten(struct buffer_head *bh, int uptodate) static int ext4_dax_fault(struct vm_area_struct *vma, struct vm_fault *vmf) { - return dax_fault(vma, vmf, ext4_get_block, ext4_end_io_unwritten); - /* Is this the right get_block? */ + return dax_fault(vma, vmf, ext4_get_block_write, ext4_end_io_unwritten); } static int ext4_dax_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf) { - return dax_mkwrite(vma, vmf, ext4_get_block, ext4_end_io_unwritten); + return dax_mkwrite(vma, vmf, ext4_get_block_write, + ext4_end_io_unwritten); } static const struct vm_operations_struct ext4_dax_vm_ops = { -- 2.1.4