From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-oi0-f72.google.com (mail-oi0-f72.google.com [209.85.218.72]) by kanga.kvack.org (Postfix) with ESMTP id 78D3D6B0268 for ; Mon, 9 Oct 2017 13:10:44 -0400 (EDT) Received: by mail-oi0-f72.google.com with SMTP id h200so4575215oib.18 for ; Mon, 09 Oct 2017 10:10:44 -0700 (PDT) Received: from mail-sor-f41.google.com (mail-sor-f41.google.com. [209.85.220.41]) by mx.google.com with SMTPS id e65sor2085118oif.122.2017.10.09.10.10.43 for (Google Transport Security); Mon, 09 Oct 2017 10:10:43 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: <20171009034506.GI3666@dastard> References: <150732931273.22363.8436792888326501071.stgit@dwillia2-desk3.amr.corp.intel.com> <150732936625.22363.7638037715540836828.stgit@dwillia2-desk3.amr.corp.intel.com> <20171009034506.GI3666@dastard> From: Dan Williams Date: Mon, 9 Oct 2017 10:10:42 -0700 Message-ID: Subject: Re: [PATCH v7 09/12] xfs: wire up ->lease_direct() Content-Type: text/plain; charset="UTF-8" Sender: owner-linux-mm@kvack.org List-ID: To: Dave Chinner Cc: "linux-nvdimm@lists.01.org" , linux-xfs@vger.kernel.org, Jan Kara , "Darrick J. Wong" , linux-rdma@vger.kernel.org, Linux API , Christoph Hellwig , "J. Bruce Fields" , Linux MM , Jeff Moyer , linux-fsdevel , Jeff Layton , Ross Zwisler On Sun, Oct 8, 2017 at 8:45 PM, Dave Chinner wrote: > On Fri, Oct 06, 2017 at 03:36:06PM -0700, Dan Williams wrote: >> A 'lease_direct' lease requires that the vma have a valid MAP_DIRECT >> mapping established. For xfs we establish a new lease and then check if >> the MAP_DIRECT mapping has been broken. We want to be sure that the >> process will receive notification that the MAP_DIRECT mapping is being >> torn down so it knows why other code paths are throwing failures. >> >> For example in the RDMA/ibverbs case we want ibv_reg_mr() to fail if the >> MAP_DIRECT mapping is invalid or in the process of being invalidated. >> >> Cc: Jan Kara >> Cc: Jeff Moyer >> Cc: Christoph Hellwig >> Cc: Dave Chinner >> Cc: "Darrick J. Wong" >> Cc: Ross Zwisler >> Cc: Jeff Layton >> Cc: "J. Bruce Fields" >> Signed-off-by: Dan Williams >> --- >> fs/xfs/xfs_file.c | 28 ++++++++++++++++++++++++++++ >> 1 file changed, 28 insertions(+) >> >> diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c >> index e35518600e28..823b65f17429 100644 >> --- a/fs/xfs/xfs_file.c >> +++ b/fs/xfs/xfs_file.c >> @@ -1166,6 +1166,33 @@ xfs_filemap_direct_close( >> put_map_direct_vma(vma->vm_private_data); >> } >> >> +static struct lease_direct * >> +xfs_filemap_direct_lease( >> + struct vm_area_struct *vma, >> + void (*break_fn)(void *), >> + void *owner) >> +{ >> + struct lease_direct *ld; >> + >> + ld = map_direct_lease(vma, break_fn, owner); >> + >> + if (IS_ERR(ld)) >> + return ld; >> + >> + /* >> + * We now have an established lease while the base MAP_DIRECT >> + * lease was not broken. So, we know that the "lease holder" will >> + * receive a SIGIO notification when the lease is broken and >> + * take any necessary cleanup actions. >> + */ >> + if (!is_map_direct_broken(vma->vm_private_data)) >> + return ld; >> + >> + map_direct_lease_destroy(ld); >> + >> + return ERR_PTR(-ENXIO); > > What's any of this got to do with XFS? Shouldn't it be in generic > code, and called generic_filemap_direct_lease()? True, I can move this to generic code. The filesystem is in charge of where it wants to store the 'struct map_direct_state' context, but for generic_filemap_direct_lease() it can just assume that it is stored in ->vm_private_data. I'll add comments to this effect on the new routine. -- 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