Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932576AbVL2Am3 (ORCPT ); Wed, 28 Dec 2005 19:42:29 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S964949AbVL2AjR (ORCPT ); Wed, 28 Dec 2005 19:39:17 -0500 Received: from mx.pathscale.com ([64.160.42.68]:50408 "EHLO mx.pathscale.com") by vger.kernel.org with ESMTP id S932570AbVL2AjJ (ORCPT ); Wed, 28 Dec 2005 19:39:09 -0500 Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: [PATCH 7 of 20] ipath - MMIO copy routines X-Mercurial-Node: ffbd416f30d4d7af37f21d55c7545b8edbbc232a Message-Id: In-Reply-To: Date: Wed, 28 Dec 2005 16:31:26 -0800 From: "Bryan O'Sullivan" To: linux-kernel@vger.kernel.org, openib-general@openib.org Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 17602 Lines: 623 Signed-off-by: Bryan O'Sullivan diff -r 9e8d017ed298 -r ffbd416f30d4 drivers/infiniband/hw/ipath/ipath_copy.c --- /dev/null Thu Jan 1 00:00:00 1970 +0000 +++ b/drivers/infiniband/hw/ipath/ipath_copy.c Wed Dec 28 14:19:42 2005 -0800 @@ -0,0 +1,612 @@ +/* + * Copyright (c) 2003, 2004, 2005, 2006 PathScale, Inc. All rights reserved. + * + * This software is available to you under a choice of one of two + * licenses. You may choose to be licensed under the terms of the GNU + * General Public License (GPL) Version 2, available from the file + * COPYING in the main directory of this source tree, or the + * OpenIB.org BSD license below: + * + * Redistribution and use in source and binary forms, with or + * without modification, are permitted provided that the following + * conditions are met: + * + * - Redistributions of source code must retain the above + * copyright notice, this list of conditions and the following + * disclaimer. + * + * - Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following + * disclaimer in the documentation and/or other materials + * provided with the distribution. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + * + * Patent licenses, if any, provided herein do not apply to + * combinations of this program with other software, or any other + * product whatsoever. + */ + +/* + * This file provides support for doing sk_buff buffer swapping between + * the low level driver eager buffers, and the network layer. It's part + * of the core driver, rather than the ether driver, because it relies + * on variables and functions in the core driver. It exports a single + * entry point for use in the ipath_ether module. + */ + +#include +#include +#include +#include +#include +#include +#include +#include + +#include /* we can generate our own crc's for testing */ + +#include "ipath_kernel.h" +#include "ips_common.h" +#include "ipath_layer.h" + +/* + * Allocate a PIO send buffer, initialize the header and copy it out. + */ +static int layer_send_getpiobuf(struct copy_data_s *cdp) +{ + uint32_t device = cdp->device; + uint32_t extra_bytes; + uint32_t len, nwords; + uint32_t __iomem *piobuf; + + if (!(piobuf = ipath_getpiobuf(device, NULL))) { + cdp->error = -EBUSY; + return cdp->error; + } + + /* + * Compute the max amount of data that can fit into a PIO buffer. + * buffer size - header size - trigger qword length & flags - CRC + */ + len = devdata[device].ipath_ibmaxlen - + sizeof(struct ether_header_typ) - 8 - (SIZE_OF_CRC << 2); + if (len > devdata[device].ipath_rcvegrbufsize) + len = devdata[device].ipath_rcvegrbufsize; + if (len > (cdp->len + cdp->extra)) + len = (cdp->len + cdp->extra); + /* Compute word aligment (i.e., (len & 3) ? 4 - (len & 3) : 0) */ + extra_bytes = (4 - len) & 3; + nwords = (sizeof(struct ether_header_typ) + len + extra_bytes) >> 2; + cdp->hdr->lrh[2] = htons(nwords + SIZE_OF_CRC); + cdp->hdr->bth[0] = htonl((OPCODE_ITH4X << 24) + (extra_bytes << 20) + + IPS_DEFAULT_P_KEY); + cdp->hdr->sub_opcode = OPCODE_ENCAP; + + cdp->hdr->bth[2] = 0; + /* Generate an interrupt on the receive side for the last fragment. */ + cdp->hdr->iph.pkt_flags = ((cdp->len+cdp->extra) == len) ? INFINIPATH_KPF_INTR : 0; + cdp->hdr->iph.chksum = (uint16_t) IPS_LRH_BTH + + (uint16_t) (nwords + SIZE_OF_CRC) - + (uint16_t) ((cdp->hdr->iph.ver_port_tid_offset >> 16)&0xFFFF) - + (uint16_t) (cdp->hdr->iph.ver_port_tid_offset & 0xFFFF) - + (uint16_t) cdp->hdr->iph.pkt_flags; + + _IPATH_VDBG("send %d (%x %x %x %x %x %x %x)\n", nwords, + cdp->hdr->lrh[0], cdp->hdr->lrh[1], + cdp->hdr->lrh[2], cdp->hdr->lrh[3], + cdp->hdr->bth[0], cdp->hdr->bth[1], cdp->hdr->bth[2]); + /* + * Write len to control qword, no flags. + * +1 is for the qword padding of pbc. + */ + writeq(nwords + 1ULL, (uint64_t __iomem *) piobuf); + /* we have to flush after the PBC for correctness on some cpus + * or WC buffer can be written out of order */ + mb(); + piobuf += 2; + memcpy_toio32(piobuf, cdp->hdr, sizeof(struct ether_header_typ) >> 2); + cdp->csum_pio = &((struct ether_header_typ __iomem *) piobuf)->csum; + cdp->to = piobuf + (sizeof(struct ether_header_typ) >> 2); + cdp->flen = nwords - (sizeof(struct ether_header_typ) >> 2); + cdp->hdr->frag_num++; + return 0; +} + +/* + * copy the last full dword when that's the "extra" word, preceding it + * with a memory fence, so that all prior data is written to the PIO + * buffer before the trigger word, to enforce the correct bus ordering + * of the WC buffer contents on the bus. + */ +static inline unsigned copy_extra_dword(struct copy_data_s *cdp, unsigned dosum) +{ + if (!cdp->flen && layer_send_getpiobuf(cdp) < 0) + return 1; + /* write the checksum before the last PIO write, if requested. */ + if (dosum && cdp->flen == 1) + writel(csum_fold(cdp->csum), cdp->csum_pio); + mb(); + writel(cdp->u.w, cdp->to++); + mb(); + cdp->extra = 0; + cdp->flen -= 1; + return 0; +} + +/* + * copy a PIO buffer's worth (or the skb fragment, at least) to the PIO + * buffer, adding a memory fence before the last word. We need the fence + * as part of forcing the WC ordering on some cpus, for the cases where + * it will be the trigger word. The final fence after the trigger word + * will be done either at the next chunk, or on final return from the caller + * Takes max byte count, returns byte count actually done (always rounded + * to dword multiple). + */ +static uint32_t copy_a_buffer(struct copy_data_s *cdp, void *p, uint32_t n, + unsigned dosum) +{ + uint32_t *p32; + + if (!cdp->flen && layer_send_getpiobuf(cdp) < 0) + return -1; + if (n > cdp->flen) + n = cdp->flen; + if (dosum && cdp->flen == n) + writel(csum_fold(cdp->csum), cdp->csum_pio); + p32 = p; + memcpy_toio32(cdp->to, p32, n-1); + cdp->to += n-1; + mb(); + writel(p32[n-1], cdp->to++); + mb(); + _IPATH_PDBG("trigger write to pio %p\n", &p32[n-1]); + cdp->flen -= n; + n <<= 2; + cdp->offset += n; + cdp->len -= n; + return n; +} + +/* + * Copy data out of one or a chain of sk_buffs, into the PIO buffer. + * Fragment an sk_buff into multiple IB packets if the amount of data is + * more than a single eager send. + * Offset and len are in bytes. + * Note that this function is recursive! + */ +static void copy_bits(const struct sk_buff *skb, unsigned int offset, + unsigned int len, struct copy_data_s *cdp) +{ + unsigned int start = skb_headlen(skb); + unsigned int i, copy; + uint32_t n; + uint8_t *p; + + /* Copy header. */ + if ((int)(copy = start - offset) > 0) { + if (copy > len) + copy = len; + p = skb->data + offset; + offset += copy; + len -= copy; + /* If the alignment buffer is not empty, fill it and write it out. */ + if (cdp->extra) { + if (cdp->extra == 4) { + if (copy_extra_dword(cdp, 0)) + return; + } + else while (copy != 0) { + cdp->u.buf[cdp->extra] = *p++; + copy--; + cdp->offset++; + cdp->len--; + + if (++cdp->extra == 4) { + if (copy_extra_dword(cdp, 0)) + return; + break; + } + } + } + while (copy >= 4) { + n = copy_a_buffer(cdp, p, copy>>2, 0); + if (n == -1) + return; + p += n; + copy -= n; + } + /* + * Either cdp->extra is zero or copy is zero which means that + * the loop here can't cause the alignment buffer to fill up. + */ + while (copy != 0) { + cdp->u.buf[cdp->extra++] = *p++; + copy--; + cdp->offset++; + cdp->len--; + + } + if (len == 0) + return; + } + + for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { + skb_frag_t *frag = &skb_shinfo(skb)->frags[i]; + unsigned int end; + + end = start + frag->size; + if ((int)(copy = end - offset) > 0) { + uint8_t *vaddr; + + if (copy > len) + copy = len; + vaddr = kmap_skb_frag(frag); + p = vaddr + frag->page_offset + offset - start; + offset += copy; + len -= copy; + /* If the alignment buffer is not empty, fill it and write it out. */ + if (cdp->extra) { + if (cdp->extra == 4) { + if (copy_extra_dword(cdp, 0)) + return; + } + else while (copy != 0) { + cdp->u.buf[cdp->extra] = *p++; + copy--; + cdp->offset++; + cdp->len--; + + if (++cdp->extra == 4) { + if (copy_extra_dword(cdp, 0)) + return; + break; + } + } + } + while (copy >= 4) { + n = copy_a_buffer(cdp, p, copy>>2, 0); + if (n == -1) + return; + p += n; + copy -= n; + } + /* + * Either cdp->extra is zero or copy is zero which means that + * the loop here can't cause the alignment buffer to fill up. + */ + while (copy != 0) { + cdp->u.buf[cdp->extra++] = *p++; + copy--; + cdp->offset++; + cdp->len--; + } + kunmap_skb_frag(vaddr); + + if (len == 0) + return; + } + start = end; + } + + if (skb_shinfo(skb)->frag_list) { + struct sk_buff *list = skb_shinfo(skb)->frag_list; + + for (; list; list = list->next) { + unsigned int end; + + end = start + list->len; + if ((int)(copy = end - offset) > 0) { + if (copy > len) + copy = len; + copy_bits(list, offset - start, copy, cdp); + if (cdp->error || (len -= copy) == 0) + return; + } + start = end; + } + } + if (len) + cdp->error = -EFAULT; +} + +/* + * Copy data out of one or a chain of sk_buffs, into the PIO buffer, generating + * the checksum as we go. + * Fragment an sk_buff into multiple IB packets if the amount of data is + * more than a single eager send. + * Offset and len are in bytes. + * Note that this function is recursive! + */ +static void copy_and_csum_bits(const struct sk_buff *skb, unsigned int offset, + unsigned int len, struct copy_data_s *cdp) +{ + unsigned int start = skb_headlen(skb); + unsigned int i, copy; + unsigned int csum2; + uint32_t n; + uint8_t *p; + + /* Copy header. */ + if ((int)(copy = start - offset) > 0) { + if (copy > len) + copy = len; + p = skb->data + offset; + offset += copy; + len -= copy; + if (!cdp->checksum_calc) { + cdp->checksum_calc = 1; + + csum2 = csum_partial(p, copy, 0); + cdp->csum = csum_block_add(cdp->csum, csum2, cdp->pos); + cdp->pos += copy; + } + /* If the alignment buffer is not empty, fill it and write it out. */ + if (cdp->extra) { + if (cdp->extra == 4) { + if (copy_extra_dword(cdp, 1)) + goto done; + } + else while (copy != 0) { + cdp->u.buf[cdp->extra] = *p++; + copy--; + cdp->offset++; + cdp->len--; + if (++cdp->extra == 4) { + if (copy_extra_dword(cdp, 1)) + goto done; + break; + } + } + } + + while (copy >= 4) { + n = copy_a_buffer(cdp, p, copy>>2, 1); + if (n == -1) + goto done; + p += n; + copy -= n; + } + /* + * Either cdp->extra is zero or copy is zero which means that + * the loop here can't cause the alignment buffer to fill up. + */ + while (copy != 0) { + cdp->u.buf[cdp->extra++] = *p++; + copy--; + cdp->offset++; + cdp->len--; + } + + cdp->checksum_calc = 0; + + if (len == 0) + goto done; + } + + for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { + skb_frag_t *frag = &skb_shinfo(skb)->frags[i]; + unsigned int end; + + end = start + frag->size; + if ((int)(copy = end - offset) > 0) { + uint8_t *vaddr; + + if (copy > len) + copy = len; + vaddr = kmap_skb_frag(frag); + p = vaddr + frag->page_offset + offset - start; + offset += copy; + len -= copy; + + if (!cdp->checksum_calc) { + cdp->checksum_calc = 1; + + csum2 = csum_partial(p, copy, 0); + cdp->csum = csum_block_add(cdp->csum, csum2, + cdp->pos); + cdp->pos += copy; + } + /* If the alignment buffer is not empty, fill it and write it out. */ + if (cdp->extra) { + if (cdp->extra == 4) { + if (copy_extra_dword(cdp, 1)) { + kunmap_skb_frag(vaddr); + goto done; + } + } + else while (copy != 0) { + cdp->u.buf[cdp->extra] = *p++; + copy--; + cdp->offset++; + cdp->len--; + + if (++cdp->extra == 4) { + if (copy_extra_dword(cdp, 1)) { + kunmap_skb_frag(vaddr); + goto done; + } + break; + } + } + } + while (copy >= 4) { + n = copy_a_buffer(cdp, p, copy>>2, 1); + if (n == -1) { + kunmap_skb_frag(vaddr); + goto done; + } + p += n; + copy -= n; + } + /* + * Either cdp->extra is zero or copy is zero which means that + * the loop here can't cause the alignment buffer to fill up. + */ + while (copy != 0) { + cdp->u.buf[cdp->extra++] = *p++; + copy--; + cdp->offset++; + cdp->len--; + } + kunmap_skb_frag(vaddr); + + cdp->checksum_calc = 0; + + if (len == 0) + goto done; + } + start = end; + } + + if (skb_shinfo(skb)->frag_list) { + struct sk_buff *list = skb_shinfo(skb)->frag_list; + + for (; list; list = list->next) { + unsigned int end; + + end = start + list->len; + if ((int)(copy = end - offset) > 0) { + if (copy > len) + copy = len; + copy_and_csum_bits(list, offset - start, copy, cdp); + if (cdp->error || (len -= copy) == 0) + goto done; + offset += copy; + } + start = end; + } + } + if (len) + cdp->error = -EFAULT; +done: + /* we have to flush after trigger word for correctness on some cpus + * or WC buffer can be written out of order; needed even if + * there was an error */ + mb(); +} + +/* + * Note that the header should have the unchanging parts + * initialized but the rest of the header is computed as needed in + * order to break up skb data buffers larger than the hardware MTU. + * In other words, the Linux network stack MTU can be larger than the + * hardware MTU. + */ +int ipath_layer_send_skb(struct copy_data_s *cdata) +{ + int ret = 0; + uint16_t vlsllnh; + int device = cdata->device; + + if (device >= infinipath_max) { + _IPATH_INFO("Invalid unit %u, failing\n", device); + return -EINVAL; + } + if (!(devdata[device].ipath_flags & IPATH_RCVHDRSZ_SET)) { + _IPATH_INFO("send while not open\n"); + ret = -EINVAL; + } + else if ((devdata[device].ipath_flags & (IPATH_LINKUNK | IPATH_LINKDOWN)) + || devdata[device].ipath_lid == 0) { + /* lid check is for when sma hasn't yet configured */ + ret = -ENETDOWN; + _IPATH_VDBG("send while not ready, mylid=%u, flags=0x%x\n", + devdata[device].ipath_lid, devdata[device].ipath_flags); + } + vlsllnh = *((uint16_t *) cdata->hdr); + if (vlsllnh != htons(IPS_LRH_BTH)) { + _IPATH_DBG("Warning: lrh[0] wrong (%x, not %x); not sending\n", + vlsllnh, htons(IPS_LRH_BTH)); + ret = -EINVAL; + } + if (ret) + goto done; + + cdata->error = 0; /* clear last calls error */ + + if (cdata->skb->ip_summed == CHECKSUM_HW) { + unsigned int csstart = cdata->skb->h.raw - cdata->skb->data; + + /* + * Computing the checksum is a bit tricky since if we fragment + * the packet, the fragment that should contain the checksum + * will have already been sent. The solution is to store the checksum + * in the header of the last fragment just before we write the + * last data word which triggers the last fragment to be sent. + * The receiver will check the header "tag" field, see that + * there is a checksum, and store the checksum back into the packet. + * + * Save the offset of the two byte checksum. + * Note that we have to add 2 to account for the two bytes of the + * ethernet address we stripped from the packet and put in the header. + */ + cdata->hdr->csum_offset = csstart + cdata->skb->csum + 2; + + if (cdata->offset < csstart) + copy_bits(cdata->skb, cdata->offset, + csstart - cdata->offset, cdata); + + if (cdata->error) { + ret = cdata->error; + goto done; + } + + if (cdata->offset < cdata->skb->len) + copy_and_csum_bits(cdata->skb, cdata->offset, + cdata->skb->len - cdata->offset, cdata); + + if (cdata->error) { + ret = cdata->error; + goto done; + } + + if (cdata->extra) { + while (cdata->extra < 4) + cdata->u.buf[cdata->extra++] = 0; + (void)copy_extra_dword(cdata, 1); + } + } + else { + copy_bits(cdata->skb, cdata->offset, + cdata->skb->len - cdata->offset, cdata); + + if (cdata->error) { + ret = cdata->error; + goto done; + } + + if (cdata->extra) { + while (cdata->extra < 4) + cdata->u.buf[cdata->extra++] = 0; + (void)copy_extra_dword(cdata, 1); + } + } + + if (cdata->error) { + ret = cdata->error; + if (cdata->error != -EBUSY) + _IPATH_UNIT_ERROR(device, + "layer_send copy_bits failed with error %d\n", + -ret); + } + + ipath_stats.sps_ether_spkts++; /* another ether packet sent */ + +done: + /* we have to flush after trigger word for correctness on some cpus + * or WC buffer can be written out of order; needed even if + * there was an error */ + mb(); + return ret; +} + +EXPORT_SYMBOL(ipath_layer_send_skb); + - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/