From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tom Talpey Subject: Re: [Patch v2 08/15] CIFS: SMBD: Support page offset in RDMA send Date: Sat, 23 Jun 2018 22:11:39 -0400 Message-ID: References: <20180530194807.31657-1-longli@linuxonhyperv.com> <20180530194807.31657-9-longli@linuxonhyperv.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20180530194807.31657-9-longli@linuxonhyperv.com> Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org To: longli@microsoft.com, Steve French , linux-cifs@vger.kernel.org, samba-technical@lists.samba.org, linux-kernel@vger.kernel.org, linux-rdma@vger.kernel.org List-Id: linux-rdma@vger.kernel.org On 5/30/2018 3:48 PM, Long Li wrote: > From: Long Li > > The RDMA send function needs to look at offset in the request pages, and > send data starting from there. > > Signed-off-by: Long Li > --- > fs/cifs/smbdirect.c | 27 +++++++++++++++++++-------- > 1 file changed, 19 insertions(+), 8 deletions(-) > > diff --git a/fs/cifs/smbdirect.c b/fs/cifs/smbdirect.c > index c62f7c9..6141e3c 100644 > --- a/fs/cifs/smbdirect.c > +++ b/fs/cifs/smbdirect.c > @@ -17,6 +17,7 @@ > #include > #include "smbdirect.h" > #include "cifs_debug.h" > +#include "cifsproto.h" > > static struct smbd_response *get_empty_queue_buffer( > struct smbd_connection *info); > @@ -2082,7 +2083,7 @@ int smbd_send(struct smbd_connection *info, struct smb_rqst *rqst) > struct kvec vec; > int nvecs; > int size; > - int buflen = 0, remaining_data_length; > + unsigned int buflen = 0, remaining_data_length; > int start, i, j; > int max_iov_size = > info->max_send_size - sizeof(struct smbd_data_transfer); > @@ -2113,10 +2114,17 @@ int smbd_send(struct smbd_connection *info, struct smb_rqst *rqst) > buflen += iov[i].iov_len; > } > > - /* add in the page array if there is one */ > + /* > + * Add in the page array if there is one. The caller needs to set > + * rq_tailsz to PAGE_SIZE when the buffer has multiple pages and > + * ends at page boundary > + */ > if (rqst->rq_npages) { > - buflen += rqst->rq_pagesz * (rqst->rq_npages - 1); > - buflen += rqst->rq_tailsz; > + if (rqst->rq_npages == 1) > + buflen += rqst->rq_tailsz; > + else > + buflen += rqst->rq_pagesz * (rqst->rq_npages - 1) - > + rqst->rq_offset + rqst->rq_tailsz; > } This code is really confusing and redundant. It tests npages > 0, then tests npages == 1, then does an else. Why not call the helper like the following smbd_send()? Tom. > > if (buflen + sizeof(struct smbd_data_transfer) > > @@ -2213,8 +2221,9 @@ int smbd_send(struct smbd_connection *info, struct smb_rqst *rqst) > > /* now sending pages if there are any */ > for (i = 0; i < rqst->rq_npages; i++) { > - buflen = (i == rqst->rq_npages-1) ? > - rqst->rq_tailsz : rqst->rq_pagesz; > + unsigned int offset; > + > + rqst_page_get_length(rqst, i, &buflen, &offset); > nvecs = (buflen + max_iov_size - 1) / max_iov_size; > log_write(INFO, "sending pages buflen=%d nvecs=%d\n", > buflen, nvecs); > @@ -2225,9 +2234,11 @@ int smbd_send(struct smbd_connection *info, struct smb_rqst *rqst) > remaining_data_length -= size; > log_write(INFO, "sending pages i=%d offset=%d size=%d" > " remaining_data_length=%d\n", > - i, j*max_iov_size, size, remaining_data_length); > + i, j*max_iov_size+offset, size, > + remaining_data_length); > rc = smbd_post_send_page( > - info, rqst->rq_pages[i], j*max_iov_size, > + info, rqst->rq_pages[i], > + j*max_iov_size + offset, > size, remaining_data_length); > if (rc) > goto done; >