| Message ID | 20180417004918.29213-3-longli@linuxonhyperv.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Mon, Apr 16, 2018 at 05:49:15PM -0700, Long Li wrote: > From: Long Li <longli@microsoft.com> > > It's not necessary to allocate another iov when going through the buffers > in smbd_send() through RDMA send. > > Remove it to reduce stack size. > > Signed-off-by: Long Li <longli@microsoft.com> > --- > fs/cifs/smbdirect.c | 36 ++++++++++++------------------------ > 1 file changed, 12 insertions(+), 24 deletions(-) > > diff --git a/fs/cifs/smbdirect.c b/fs/cifs/smbdirect.c > index b5c6c0d..f575e9a 100644 > --- a/fs/cifs/smbdirect.c > +++ b/fs/cifs/smbdirect.c > @@ -2088,7 +2088,7 @@ int smbd_send(struct smbd_connection *info, struct smb_rqst *rqst) > int start, i, j; > int max_iov_size = > info->max_send_size - sizeof(struct smbd_data_transfer); > - struct kvec iov[SMBDIRECT_MAX_SGE]; > + struct kvec *iov; > int rc; > > info->smbd_send_pending++; > @@ -2099,32 +2099,20 @@ int smbd_send(struct smbd_connection *info, struct smb_rqst *rqst) > } > > /* > - * This usually means a configuration error > - * We use RDMA read/write for packet size > rdma_readwrite_threshold > - * as long as it's properly configured we should never get into this > - * situation > - */ > - if (rqst->rq_nvec + rqst->rq_npages > SMBDIRECT_MAX_SGE) { > - log_write(ERR, "maximum send segment %x exceeding %x\n", > - rqst->rq_nvec + rqst->rq_npages, SMBDIRECT_MAX_SGE); > - rc = -EINVAL; > - goto done; > - } > - > - /* > - * Remove the RFC1002 length defined in MS-SMB2 section 2.1 > - * It is used only for TCP transport > + * Skip the RFC1002 length defined in MS-SMB2 section 2.1 > + * It is used only for TCP transport in the iov[0] > * In future we may want to add a transport layer under protocol > * layer so this will only be issued to TCP transport > */ > - iov[0].iov_base = (char *)rqst->rq_iov[0].iov_base + 4; > - iov[0].iov_len = rqst->rq_iov[0].iov_len - 4; > - buflen += iov[0].iov_len; > + > + if (rqst->rq_iov[0].iov_len != 4) { > + log_write(ERR, "expected the pdu length in 1st iov, but got 0x%lu\n", rqst->rq_iov[0].iov_len); > + return -EINVAL; > + } > + iov = &rqst->rq_iov[1]; > > /* total up iov array first */ > - for (i = 1; i < rqst->rq_nvec; i++) { > - iov[i].iov_base = rqst->rq_iov[i].iov_base; > - iov[i].iov_len = rqst->rq_iov[i].iov_len; > + for (i = 0; i < rqst->rq_nvec-1; i++) { > buflen += iov[i].iov_len; > } > > @@ -2197,14 +2185,14 @@ int smbd_send(struct smbd_connection *info, struct smb_rqst *rqst) > goto done; > } > i++; > - if (i == rqst->rq_nvec) > + if (i == rqst->rq_nvec-1) > break; > } > start = i; > buflen = 0; > } else { > i++; > - if (i == rqst->rq_nvec) { > + if (i == rqst->rq_nvec-1) { > /* send out all remaining vecs */ > remaining_data_length -= buflen; > log_write(INFO, > -- > 2.7.4 <formletter> This is not the correct way to submit patches for inclusion in the stable kernel tree. Please read: https://www.kernel.org/doc/html/latest/process/stable-kernel-rules.html for how to do this properly. </formletter> -- To unsubscribe from this list: send the line "unsubscribe linux-cifs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/fs/cifs/smbdirect.c b/fs/cifs/smbdirect.c index b5c6c0d..f575e9a 100644 --- a/fs/cifs/smbdirect.c +++ b/fs/cifs/smbdirect.c @@ -2088,7 +2088,7 @@ int smbd_send(struct smbd_connection *info, struct smb_rqst *rqst) int start, i, j; int max_iov_size = info->max_send_size - sizeof(struct smbd_data_transfer); - struct kvec iov[SMBDIRECT_MAX_SGE]; + struct kvec *iov; int rc; info->smbd_send_pending++; @@ -2099,32 +2099,20 @@ int smbd_send(struct smbd_connection *info, struct smb_rqst *rqst) } /* - * This usually means a configuration error - * We use RDMA read/write for packet size > rdma_readwrite_threshold - * as long as it's properly configured we should never get into this - * situation - */ - if (rqst->rq_nvec + rqst->rq_npages > SMBDIRECT_MAX_SGE) { - log_write(ERR, "maximum send segment %x exceeding %x\n", - rqst->rq_nvec + rqst->rq_npages, SMBDIRECT_MAX_SGE); - rc = -EINVAL; - goto done; - } - - /* - * Remove the RFC1002 length defined in MS-SMB2 section 2.1 - * It is used only for TCP transport + * Skip the RFC1002 length defined in MS-SMB2 section 2.1 + * It is used only for TCP transport in the iov[0] * In future we may want to add a transport layer under protocol * layer so this will only be issued to TCP transport */ - iov[0].iov_base = (char *)rqst->rq_iov[0].iov_base + 4; - iov[0].iov_len = rqst->rq_iov[0].iov_len - 4; - buflen += iov[0].iov_len; + + if (rqst->rq_iov[0].iov_len != 4) { + log_write(ERR, "expected the pdu length in 1st iov, but got 0x%lu\n", rqst->rq_iov[0].iov_len); + return -EINVAL; + } + iov = &rqst->rq_iov[1]; /* total up iov array first */ - for (i = 1; i < rqst->rq_nvec; i++) { - iov[i].iov_base = rqst->rq_iov[i].iov_base; - iov[i].iov_len = rqst->rq_iov[i].iov_len; + for (i = 0; i < rqst->rq_nvec-1; i++) { buflen += iov[i].iov_len; } @@ -2197,14 +2185,14 @@ int smbd_send(struct smbd_connection *info, struct smb_rqst *rqst) goto done; } i++; - if (i == rqst->rq_nvec) + if (i == rqst->rq_nvec-1) break; } start = i; buflen = 0; } else { i++; - if (i == rqst->rq_nvec) { + if (i == rqst->rq_nvec-1) { /* send out all remaining vecs */ remaining_data_length -= buflen; log_write(INFO,