From: Long Li <lon...@microsoft.com> This patch set implements direct I/O.
In normal code path (even with cache=none), CIFS copies I/O data from user-space to kernel-space for security reasons of possible protocol required signing and encryption on user data. With this patch set, CIFS passes the I/O data directly from user-space buffer to the transport layer, when file system is mounted with "cache-none". Patch v2 addressed comments from Christoph Hellwig <h...@lst.de> and Tom Talpey <ttal...@microsoft.com> to implement direct I/O for both socket and RDMA. Long Li (15): CIFS: Introduce offset for the 1st page in data transfer structures CIFS: Add support for direct pages in rdata CIFS: Use offset when reading pages CIFS: Add support for direct pages in wdata CIFS: Calculate the correct request length based on page offset and tail size CIFS: Introduce helper function to get page offset and length in smb_rqst CIFS: When sending data on socket, pass the correct page offset CIFS: SMBD: Support page offset in RDMA send CIFS: SMBD: Support page offset in RDMA recv CIFS: SMBD: Support page offset in memory registration CIFS: Pass page offset for calculating signature CIFS: Pass page offset for encrypting CIFS: Add support for direct I/O read CIFS: Add support for direct I/O write CIFS: Add direct I/O functions to file_operations fs/cifs/cifsencrypt.c | 9 +- fs/cifs/cifsfs.c | 5 +- fs/cifs/cifsfs.h | 2 + fs/cifs/cifsglob.h | 7 +- fs/cifs/cifsproto.h | 9 +- fs/cifs/cifssmb.c | 17 ++- fs/cifs/connect.c | 5 +- fs/cifs/file.c | 389 +++++++++++++++++++++++++++++++++++++++++++++++--- fs/cifs/misc.c | 17 +++ fs/cifs/smb2ops.c | 22 +-- fs/cifs/smb2pdu.c | 20 ++- fs/cifs/smbdirect.c | 121 ++++++++++------ fs/cifs/smbdirect.h | 2 +- fs/cifs/transport.c | 34 +++-- 14 files changed, 554 insertions(+), 105 deletions(-) -- 2.7.4