From mboxrd@z Thu Jan 1 00:00:00 1970 From: Long Li Subject: [RFC PATCH 00/09] Implement direct user I/O interfaces for RDMA Date: Thu, 17 May 2018 17:22:05 -0700 Message-ID: <20180518002214.5657-1-longli@linuxonhyperv.com> Reply-To: longli@microsoft.com Return-path: Sender: linux-kernel-owner@vger.kernel.org To: Steve French , linux-cifs@vger.kernel.org, samba-technical@lists.samba.org, linux-kernel@vger.kernel.org, linux-rdma@vger.kernel.org Cc: Long Li List-Id: linux-rdma@vger.kernel.org From: Long Li This patchset implements direct user I/O through RDMA. In normal code path (even with cache=none), CIFS copies I/O data from user-space to kernel-space for security reasons. With this patchset, a new mounting option is introduced to have CIFS pin the user-space buffer into memory and performs I/O through RDMA. This avoids memory copy, at the cost of added security risk. This patchset is RFC. The work is in progress, do not merge. Long Li (9): Introduce offset for the 1st page in data transfer structures Change wdata alloc to support direct pages Change rdata alloc to support direct pages Change function to support offset when reading pages Change RDMA send to regonize page offset in the 1st page Change RDMA recv to support offset in the 1st page Support page offset in memory regsitrations Implement no-copy file I/O interfaces Introduce cache=rdma moutning option fs/cifs/cifs_fs_sb.h | 2 + fs/cifs/cifsfs.c | 19 +++ fs/cifs/cifsfs.h | 3 + fs/cifs/cifsglob.h | 6 + fs/cifs/cifsproto.h | 4 +- fs/cifs/cifssmb.c | 10 +- fs/cifs/connect.c | 13 +- fs/cifs/dir.c | 5 + fs/cifs/file.c | 351 ++++++++++++++++++++++++++++++++++++++++++---- fs/cifs/inode.c | 4 +- fs/cifs/smb2ops.c | 2 +- fs/cifs/smb2pdu.c | 22 ++- fs/cifs/smbdirect.c | 132 ++++++++++------- fs/cifs/smbdirect.h | 2 +- fs/read_write.c | 7 + include/linux/ratelimit.h | 2 +- 16 files changed, 489 insertions(+), 95 deletions(-) -- 2.7.4