diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/infiniband/sw/siw/siw_qp_tx.c | 1269 |
1 files changed, 1269 insertions, 0 deletions
diff --git a/drivers/infiniband/sw/siw/siw_qp_tx.c b/drivers/infiniband/sw/siw/siw_qp_tx.c new file mode 100644 index 000000000000..5e926fac51db --- /dev/null +++ b/drivers/infiniband/sw/siw/siw_qp_tx.c @@ -0,0 +1,1269 @@ +// SPDX-License-Identifier: GPL-2.0 or BSD-3-Clause + +/* Authors: Bernard Metzler <bmt@zurich.ibm.com> */ +/* Copyright (c) 2008-2019, IBM Corporation */ + +#include <linux/errno.h> +#include <linux/types.h> +#include <linux/net.h> +#include <linux/scatterlist.h> +#include <linux/highmem.h> +#include <net/tcp.h> + +#include <rdma/iw_cm.h> +#include <rdma/ib_verbs.h> +#include <rdma/ib_user_verbs.h> + +#include "siw.h" +#include "siw_verbs.h" +#include "siw_mem.h" + +#define MAX_HDR_INLINE \ + (((uint32_t)(sizeof(struct siw_rreq_pkt) - \ + sizeof(struct iwarp_send))) & 0xF8) + +static struct page *siw_get_pblpage(struct siw_mem *mem, u64 addr, int *idx) +{ + struct siw_pbl *pbl = mem->pbl; + u64 offset = addr - mem->va; + u64 paddr = siw_pbl_get_buffer(pbl, offset, NULL, idx); + + if (paddr) + return virt_to_page(paddr); + + return NULL; +} + +/* + * Copy short payload at provided destination payload address + */ +static int siw_try_1seg(struct siw_iwarp_tx *c_tx, u64 paddr) +{ + struct siw_wqe *wqe = &c_tx->wqe_active; + struct siw_sge *sge = &wqe->sqe.sge[0]; + u32 bytes = sge->length; + + if (bytes > MAX_HDR_INLINE || wqe->sqe.num_sge != 1) + return MAX_HDR_INLINE + 1; + + if (!bytes) + return 0; + + if (tx_flags(wqe) & SIW_WQE_INLINE) { + memcpy((void *)paddr, &wqe->sqe.sge[1], bytes); + } else { + struct siw_mem *mem = wqe->mem[0]; + + if (!mem->mem_obj) { + /* Kernel client using kva */ + memcpy((void *)paddr, (void *)sge->laddr, bytes); + } else if (c_tx->in_syscall) { + if (copy_from_user((void *)paddr, + (const void __user *)sge->laddr, + bytes)) + return -EFAULT; + } else { + unsigned int off = sge->laddr & ~PAGE_MASK; + struct page *p; + char *buffer; + int pbl_idx = 0; + + if (!mem->is_pbl) + p = siw_get_upage(mem->umem, sge->laddr); + else + p = siw_get_pblpage(mem, sge->laddr, &pbl_idx); + + if (unlikely(!p)) + return -EFAULT; + + buffer = kmap_atomic(p); + + if (likely(PAGE_SIZE - off >= bytes)) { + memcpy((void *)paddr, buffer + off, bytes); + kunmap_atomic(buffer); + } else { + unsigned long part = bytes - (PAGE_SIZE - off); + + memcpy((void *)paddr, buffer + off, part); + kunmap_atomic(buffer); + + if (!mem->is_pbl) + p = siw_get_upage(mem->umem, + sge->laddr + part); + else + p = siw_get_pblpage(mem, + sge->laddr + part, + &pbl_idx); + if (unlikely(!p)) + return -EFAULT; + + buffer = kmap_atomic(p); + memcpy((void *)(paddr + part), buffer, + bytes - part); + kunmap_atomic(buffer); + } + } + } + return (int)bytes; +} + +#define PKT_FRAGMENTED 1 +#define PKT_COMPLETE 0 + +/* + * siw_qp_prepare_tx() + * + * Prepare tx state for sending out one fpdu. Builds complete pkt + * if no user data or only immediate data are present. + * + * returns PKT_COMPLETE if complete pkt built, PKT_FRAGMENTED otherwise. + */ +static int siw_qp_prepare_tx(struct siw_iwarp_tx *c_tx) +{ + struct siw_wqe *wqe = &c_tx->wqe_active; + char *crc = NULL; + int data = 0; + + switch (tx_type(wqe)) { + case SIW_OP_READ: + case SIW_OP_READ_LOCAL_INV: + memcpy(&c_tx->pkt.ctrl, + &iwarp_pktinfo[RDMAP_RDMA_READ_REQ].ctrl, + sizeof(struct iwarp_ctrl)); + + c_tx->pkt.rreq.rsvd = 0; + c_tx->pkt.rreq.ddp_qn = htonl(RDMAP_UNTAGGED_QN_RDMA_READ); + c_tx->pkt.rreq.ddp_msn = + htonl(++c_tx->ddp_msn[RDMAP_UNTAGGED_QN_RDMA_READ]); + c_tx->pkt.rreq.ddp_mo = 0; + c_tx->pkt.rreq.sink_stag = htonl(wqe->sqe.sge[0].lkey); + c_tx->pkt.rreq.sink_to = + cpu_to_be64(wqe->sqe.sge[0].laddr); + c_tx->pkt.rreq.source_stag = htonl(wqe->sqe.rkey); + c_tx->pkt.rreq.source_to = cpu_to_be64(wqe->sqe.raddr); + c_tx->pkt.rreq.read_size = htonl(wqe->sqe.sge[0].length); + + c_tx->ctrl_len = sizeof(struct iwarp_rdma_rreq); + crc = (char *)&c_tx->pkt.rreq_pkt.crc; + break; + + case SIW_OP_SEND: + if (tx_flags(wqe) & SIW_WQE_SOLICITED) + memcpy(&c_tx->pkt.ctrl, + &iwarp_pktinfo[RDMAP_SEND_SE].ctrl, + sizeof(struct iwarp_ctrl)); + else + memcpy(&c_tx->pkt.ctrl, &iwarp_pktinfo[RDMAP_SEND].ctrl, + sizeof(struct iwarp_ctrl)); + + c_tx->pkt.send.ddp_qn = RDMAP_UNTAGGED_QN_SEND; + c_tx->pkt.send.ddp_msn = + htonl(++c_tx->ddp_msn[RDMAP_UNTAGGED_QN_SEND]); + c_tx->pkt.send.ddp_mo = 0; + + c_tx->pkt.send_inv.inval_stag = 0; + + c_tx->ctrl_len = sizeof(struct iwarp_send); + + crc = (char *)&c_tx->pkt.send_pkt.crc; + data = siw_try_1seg(c_tx, (u64)crc); + break; + + case SIW_OP_SEND_REMOTE_INV: + if (tx_flags(wqe) & SIW_WQE_SOLICITED) + memcpy(&c_tx->pkt.ctrl, + &iwarp_pktinfo[RDMAP_SEND_SE_INVAL].ctrl, + sizeof(struct iwarp_ctrl)); + else + memcpy(&c_tx->pkt.ctrl, + &iwarp_pktinfo[RDMAP_SEND_INVAL].ctrl, + sizeof(struct iwarp_ctrl)); + + c_tx->pkt.send.ddp_qn = RDMAP_UNTAGGED_QN_SEND; + c_tx->pkt.send.ddp_msn = + htonl(++c_tx->ddp_msn[RDMAP_UNTAGGED_QN_SEND]); + c_tx->pkt.send.ddp_mo = 0; + + c_tx->pkt.send_inv.inval_stag = cpu_to_be32(wqe->sqe.rkey); + + c_tx->ctrl_len = sizeof(struct iwarp_send_inv); + + crc = (char *)&c_tx->pkt.send_pkt.crc; + data = siw_try_1seg(c_tx, (u64)crc); + break; + + case SIW_OP_WRITE: + memcpy(&c_tx->pkt.ctrl, &iwarp_pktinfo[RDMAP_RDMA_WRITE].ctrl, + sizeof(struct iwarp_ctrl)); + + c_tx->pkt.rwrite.sink_stag = htonl(wqe->sqe.rkey); + c_tx->pkt.rwrite.sink_to = cpu_to_be64(wqe->sqe.raddr); + c_tx->ctrl_len = sizeof(struct iwarp_rdma_write); + + crc = (char *)&c_tx->pkt.write_pkt.crc; + data = siw_try_1seg(c_tx, (u64)crc); + break; + + case SIW_OP_READ_RESPONSE: + memcpy(&c_tx->pkt.ctrl, + &iwarp_pktinfo[RDMAP_RDMA_READ_RESP].ctrl, + sizeof(struct iwarp_ctrl)); + + /* NBO */ + c_tx->pkt.rresp.sink_stag = cpu_to_be32(wqe->sqe.rkey); + c_tx->pkt.rresp.sink_to = cpu_to_be64(wqe->sqe.raddr); + + c_tx->ctrl_len = sizeof(struct iwarp_rdma_rresp); + + crc = (char *)&c_tx->pkt.write_pkt.crc; + data = siw_try_1seg(c_tx, (u64)crc); + break; + + default: + siw_dbg_qp(tx_qp(c_tx), "stale wqe type %d\n", tx_type(wqe)); + return -EOPNOTSUPP; + } + if (unlikely(data < 0)) + return data; + + c_tx->ctrl_sent = 0; + + if (data <= MAX_HDR_INLINE) { + if (data) { + wqe->processed = data; + + c_tx->pkt.ctrl.mpa_len = + htons(c_tx->ctrl_len + data - MPA_HDR_SIZE); + + /* Add pad, if needed */ + data += -(int)data & 0x3; + /* advance CRC location after payload */ + crc += data; + c_tx->ctrl_len += data; + + if (!(c_tx->pkt.ctrl.ddp_rdmap_ctrl & DDP_FLAG_TAGGED)) + c_tx->pkt.c_untagged.ddp_mo = 0; + else + c_tx->pkt.c_tagged.ddp_to = + cpu_to_be64(wqe->sqe.raddr); + } + + *(u32 *)crc = 0; + /* + * Do complete CRC if enabled and short packet + */ + if (c_tx->mpa_crc_hd) { + crypto_shash_init(c_tx->mpa_crc_hd); + if (crypto_shash_update(c_tx->mpa_crc_hd, + (u8 *)&c_tx->pkt, + c_tx->ctrl_len)) + return -EINVAL; + crypto_shash_final(c_tx->mpa_crc_hd, (u8 *)crc); + } + c_tx->ctrl_len += MPA_CRC_SIZE; + + return PKT_COMPLETE; + } + c_tx->ctrl_len += MPA_CRC_SIZE; + c_tx->sge_idx = 0; + c_tx->sge_off = 0; + c_tx->pbl_idx = 0; + + /* + * Allow direct sending out of user buffer if WR is non signalled + * and payload is over threshold. + * Per RDMA verbs, the application should not change the send buffer + * until the work completed. In iWarp, work completion is only + * local delivery to TCP. TCP may reuse the buffer for + * retransmission. Changing unsent data also breaks the CRC, + * if applied. + */ + if (c_tx->zcopy_tx && wqe->bytes >= SENDPAGE_THRESH && + !(tx_flags(wqe) & SIW_WQE_SIGNALLED)) + c_tx->use_sendpage = 1; + else + c_tx->use_sendpage = 0; + + return PKT_FRAGMENTED; +} + +/* + * Send out one complete control type FPDU, or header of FPDU carrying + * data. Used for fixed sized packets like Read.Requests or zero length + * SENDs, WRITEs, READ.Responses, or header only. + */ +static int siw_tx_ctrl(struct siw_iwarp_tx *c_tx, struct socket *s, + int flags) +{ + struct msghdr msg = { .msg_flags = flags }; + struct kvec iov = { .iov_base = + (char *)&c_tx->pkt.ctrl + c_tx->ctrl_sent, + .iov_len = c_tx->ctrl_len - c_tx->ctrl_sent }; + + int rv = kernel_sendmsg(s, &msg, &iov, 1, + c_tx->ctrl_len - c_tx->ctrl_sent); + + if (rv >= 0) { + c_tx->ctrl_sent += rv; + + if (c_tx->ctrl_sent == c_tx->ctrl_len) + rv = 0; + else + rv = -EAGAIN; + } + return rv; +} + +/* + * 0copy TCP transmit interface: Use do_tcp_sendpages. + * + * Using sendpage to push page by page appears to be less efficient + * than using sendmsg, even if data are copied. + * + * A general performance limitation might be the extra four bytes + * trailer checksum segment to be pushed after user data. + */ +static int siw_tcp_sendpages(struct socket *s, struct page **page, int offset, + size_t size) +{ + struct sock *sk = s->sk; + int i = 0, rv = 0, sent = 0, + flags = MSG_MORE | MSG_DONTWAIT | MSG_SENDPAGE_NOTLAST; + + while (size) { + size_t bytes = min_t(size_t, PAGE_SIZE - offset, size); + + if (size + offset <= PAGE_SIZE) + flags = MSG_MORE | MSG_DONTWAIT; + + tcp_rate_check_app_limited(sk); +try_page_again: + lock_sock(sk); + rv = do_tcp_sendpages(sk, page[i], offset, bytes, flags); + release_sock(sk); + + if (rv > 0) { + size -= rv; + sent += rv; + if (rv != bytes) { + offset += rv; + bytes -= rv; + goto try_page_again; + } + offset = 0; + } else { + if (rv == -EAGAIN || rv == 0) + break; + return rv; + } + i++; + } + return sent; +} + +/* + * siw_0copy_tx() + * + * Pushes list of pages to TCP socket. If pages from multiple + * SGE's, all referenced pages of each SGE are pushed in one + * shot. + */ +static int siw_0copy_tx(struct socket *s, struct page **page, + struct siw_sge *sge, unsigned int offset, + unsigned int size) +{ + int i = 0, sent = 0, rv; + int sge_bytes = min(sge->length - offset, size); + + offset = (sge->laddr + offset) & ~PAGE_MASK; + + while (sent != size) { + rv = siw_tcp_sendpages(s, &page[i], offset, sge_bytes); + if (rv >= 0) { + sent += rv; + if (size == sent || sge_bytes > rv) + break; + + i += PAGE_ALIGN(sge_bytes + offset) >> PAGE_SHIFT; + sge++; + sge_bytes = min(sge->length, size - sent); + offset = sge->laddr & ~PAGE_MASK; + } else { + sent = rv; + break; + } + } + return sent; +} + +#define MAX_TRAILER (MPA_CRC_SIZE + 4) + +static void siw_unmap_pages(struct page **pages, int hdr_len, int num_maps) +{ + if (hdr_len) { + ++pages; + --num_maps; + } + while (num_maps-- > 0) { + kunmap(*pages); + pages++; + } +} + +/* + * siw_tx_hdt() tries to push a complete packet to TCP where all + * packet fragments are referenced by the elements of one iovec. + * For the data portion, each involved page must be referenced by + * one extra element. All sge's data can be non-aligned to page + * boundaries. Two more elements are referencing iWARP header + * and trailer: + * MAX_ARRAY = 64KB/PAGE_SIZE + 1 + (2 * (SIW_MAX_SGE - 1) + HDR + TRL + */ +#define MAX_ARRAY ((0xffff / PAGE_SIZE) + 1 + (2 * (SIW_MAX_SGE - 1) + 2)) + +/* + * Write out iov referencing hdr, data and trailer of current FPDU. + * Update transmit state dependent on write return status + */ +static int siw_tx_hdt(struct siw_iwarp_tx *c_tx, struct socket *s) +{ + struct siw_wqe *wqe = &c_tx->wqe_active; + struct siw_sge *sge = &wqe->sqe.sge[c_tx->sge_idx]; + struct kvec iov[MAX_ARRAY]; + struct page *page_array[MAX_ARRAY]; + struct msghdr msg = { .msg_flags = MSG_DONTWAIT | MSG_EOR }; + + int seg = 0, do_crc = c_tx->do_crc, is_kva = 0, rv; + unsigned int data_len = c_tx->bytes_unsent, hdr_len = 0, trl_len = 0, + sge_off = c_tx->sge_off, sge_idx = c_tx->sge_idx, + pbl_idx = c_tx->pbl_idx; + + if (c_tx->state == SIW_SEND_HDR) { + if (c_tx->use_sendpage) { + rv = siw_tx_ctrl(c_tx, s, MSG_DONTWAIT | MSG_MORE); + if (rv) + goto done; + + c_tx->state = SIW_SEND_DATA; + } else { + iov[0].iov_base = + (char *)&c_tx->pkt.ctrl + c_tx->ctrl_sent; + iov[0].iov_len = hdr_len = + c_tx->ctrl_len - c_tx->ctrl_sent; + seg = 1; + } + } + + wqe->processed += data_len; + + while (data_len) { /* walk the list of SGE's */ + unsigned int sge_len = min(sge->length - sge_off, data_len); + unsigned int fp_off = (sge->laddr + sge_off) & ~PAGE_MASK; + struct siw_mem *mem; + + if (!(tx_flags(wqe) & SIW_WQE_INLINE)) { + mem = wqe->mem[sge_idx]; + if (!mem->mem_obj) + is_kva = 1; + } else { + is_kva = 1; + } + if (is_kva && !c_tx->use_sendpage) { + /* + * tx from kernel virtual address: either inline data + * or memory region with assigned kernel buffer + */ + iov[seg].iov_base = (void *)(sge->laddr + sge_off); + iov[seg].iov_len = sge_len; + + if (do_crc) + crypto_shash_update(c_tx->mpa_crc_hd, + iov[seg].iov_base, + sge_len); + sge_off += sge_len; + data_len -= sge_len; + seg++; + goto sge_done; + } + + while (sge_len) { + size_t plen = min((int)PAGE_SIZE - fp_off, sge_len); + + if (!is_kva) { + struct page *p; + + if (mem->is_pbl) + p = siw_get_pblpage( + mem, sge->laddr + sge_off, + &pbl_idx); + else + p = siw_get_upage(mem->umem, + sge->laddr + sge_off); + if (unlikely(!p)) { + if (hdr_len) + seg--; + if (!c_tx->use_sendpage && seg) { + siw_unmap_pages(page_array, + hdr_len, seg); + } + wqe->processed -= c_tx->bytes_unsent; + rv = -EFAULT; + goto done_crc; + } + page_array[seg] = p; + + if (!c_tx->use_sendpage) { + iov[seg].iov_base = kmap(p) + fp_off; + iov[seg].iov_len = plen; + if (do_crc) + crypto_shash_update( + c_tx->mpa_crc_hd, + iov[seg].iov_base, + plen); + } else if (do_crc) + crypto_shash_update( + c_tx->mpa_crc_hd, + page_address(p) + fp_off, + plen); + } else { + u64 pa = ((sge->laddr + sge_off) & PAGE_MASK); + + page_array[seg] = virt_to_page(pa); + if (do_crc) + crypto_shash_update( + c_tx->mpa_crc_hd, + (void *)(sge->laddr + sge_off), + plen); + } + + sge_len -= plen; + sge_off += plen; + data_len -= plen; + fp_off = 0; + + if (++seg > (int)MAX_ARRAY) { + siw_dbg_qp(tx_qp(c_tx), "to many fragments\n"); + if (!is_kva && !c_tx->use_sendpage) { + siw_unmap_pages(page_array, hdr_len, + seg - 1); + } + wqe->processed -= c_tx->bytes_unsent; + rv = -EMSGSIZE; + goto done_crc; + } + } +sge_done: + /* Update SGE variables at end of SGE */ + if (sge_off == sge->length && + (data_len != 0 || wqe->processed < wqe->bytes)) { + sge_idx++; + sge++; + sge_off = 0; + } + } + /* trailer */ + if (likely(c_tx->state != SIW_SEND_TRAILER)) { + iov[seg].iov_base = &c_tx->trailer.pad[4 - c_tx->pad]; + iov[seg].iov_len = trl_len = MAX_TRAILER - (4 - c_tx->pad); + } else { + iov[seg].iov_base = &c_tx->trailer.pad[c_tx->ctrl_sent]; + iov[seg].iov_len = trl_len = MAX_TRAILER - c_tx->ctrl_sent; + } + + if (c_tx->pad) { + *(u32 *)c_tx->trailer.pad = 0; + if (do_crc) + crypto_shash_update(c_tx->mpa_crc_hd, + (u8 *)&c_tx->trailer.crc - c_tx->pad, + c_tx->pad); + } + if (!c_tx->mpa_crc_hd) + c_tx->trailer.crc = 0; + else if (do_crc) + crypto_shash_final(c_tx->mpa_crc_hd, (u8 *)&c_tx->trailer.crc); + + data_len = c_tx->bytes_unsent; + + if (c_tx->use_sendpage) { + rv = siw_0copy_tx(s, page_array, &wqe->sqe.sge[c_tx->sge_idx], + c_tx->sge_off, data_len); + if (rv == data_len) { + rv = kernel_sendmsg(s, &msg, &iov[seg], 1, trl_len); + if (rv > 0) + rv += data_len; + else + rv = data_len; + } + } else { + rv = kernel_sendmsg(s, &msg, iov, seg + 1, + hdr_len + data_len + trl_len); + if (!is_kva) + siw_unmap_pages(page_array, hdr_len, seg); + } + if (rv < (int)hdr_len) { + /* Not even complete hdr pushed or negative rv */ + wqe->processed -= data_len; + if (rv >= 0) { + c_tx->ctrl_sent += rv; + rv = -EAGAIN; + } + goto done_crc; + } + rv -= hdr_len; + + if (rv >= (int)data_len) { + /* all user data pushed to TCP or no data to push */ + if (data_len > 0 && wqe->processed < wqe->bytes) { + /* Save the current state for next tx */ + c_tx->sge_idx = sge_idx; + c_tx->sge_off = sge_off; + c_tx->pbl_idx = pbl_idx; + } + rv -= data_len; + + if (rv == trl_len) /* all pushed */ + rv = 0; + else { + c_tx->state = SIW_SEND_TRAILER; + c_tx->ctrl_len = MAX_TRAILER; + c_tx->ctrl_sent = rv + 4 - c_tx->pad; + c_tx->bytes_unsent = 0; + rv = -EAGAIN; + } + + } else if (data_len > 0) { + /* Maybe some user data pushed to TCP */ + c_tx->state = SIW_SEND_DATA; + wqe->processed -= data_len - rv; + + if (rv) { + /* + * Some bytes out. Recompute tx state based + * on old state and bytes pushed + */ + unsigned int sge_unsent; + + c_tx->bytes_unsent -= rv; + sge = &wqe->sqe.sge[c_tx->sge_idx]; + sge_unsent = sge->length - c_tx->sge_off; + + while (sge_unsent <= rv) { + rv -= sge_unsent; + c_tx->sge_idx++; + c_tx->sge_off = 0; + sge++; + sge_unsent = sge->length; + } + c_tx->sge_off += rv; + } + rv = -EAGAIN; + } +done_crc: + c_tx->do_crc = 0; +done: + return rv; +} + +static void siw_update_tcpseg(struct siw_iwarp_tx *c_tx, + struct socket *s) +{ + struct tcp_sock *tp = tcp_sk(s->sk); + + if (tp->gso_segs) { + if (c_tx->gso_seg_limit == 0) + c_tx->tcp_seglen = tp->mss_cache * tp->gso_segs; + else + c_tx->tcp_seglen = + tp->mss_cache * + min_t(u16, c_tx->gso_seg_limit, tp->gso_segs); + } else { + c_tx->tcp_seglen = tp->mss_cache; + } + /* Loopback may give odd numbers */ + c_tx->tcp_seglen &= 0xfffffff8; +} + +/* + * siw_prepare_fpdu() + * + * Prepares transmit context to send out one FPDU if FPDU will contain + * user data and user data are not immediate data. + * Computes maximum FPDU length to fill up TCP MSS if possible. + * + * @qp: QP from which to transmit + * @wqe: Current WQE causing transmission + * + * TODO: Take into account real available sendspace on socket + * to avoid header misalignment due to send pausing within + * fpdu transmission + */ +static void siw_prepare_fpdu(struct siw_qp *qp, struct siw_wqe *wqe) +{ + struct siw_iwarp_tx *c_tx = &qp->tx_ctx; + int data_len; + + c_tx->ctrl_len = + iwarp_pktinfo[__rdmap_get_opcode(&c_tx->pkt.ctrl)].hdr_len; + c_tx->ctrl_sent = 0; + + /* + * Update target buffer offset if any + */ + if (!(c_tx->pkt.ctrl.ddp_rdmap_ctrl & DDP_FLAG_TAGGED)) + /* Untagged message */ + c_tx->pkt.c_untagged.ddp_mo = cpu_to_be32(wqe->processed); + else /* Tagged message */ + c_tx->pkt.c_tagged.ddp_to = + cpu_to_be64(wqe->sqe.raddr + wqe->processed); + + data_len = wqe->bytes - wqe->processed; + if (data_len + c_tx->ctrl_len + MPA_CRC_SIZE > c_tx->tcp_seglen) { + /* Trim DDP payload to fit into current TCP segment */ + data_len = c_tx->tcp_seglen - (c_tx->ctrl_len + MPA_CRC_SIZE); + c_tx->pkt.ctrl.ddp_rdmap_ctrl &= ~DDP_FLAG_LAST; + c_tx->pad = 0; + } else { + c_tx->pkt.ctrl.ddp_rdmap_ctrl |= DDP_FLAG_LAST; + c_tx->pad = -data_len & 0x3; + } + c_tx->bytes_unsent = data_len; + + c_tx->pkt.ctrl.mpa_len = + htons(c_tx->ctrl_len + data_len - MPA_HDR_SIZE); + + /* + * Init MPA CRC computation + */ + if (c_tx->mpa_crc_hd) { + crypto_shash_init(c_tx->mpa_crc_hd); + crypto_shash_update(c_tx->mpa_crc_hd, (u8 *)&c_tx->pkt, + c_tx->ctrl_len); + c_tx->do_crc = 1; + } +} + +/* + * siw_check_sgl_tx() + * + * Check permissions for a list of SGE's (SGL). + * A successful check will have all memory referenced + * for transmission resolved and assigned to the WQE. + * + * @pd: Protection Domain SGL should belong to + * @wqe: WQE to be checked + * @perms: requested access permissions + * + */ + +static int siw_check_sgl_tx(struct ib_pd *pd, struct siw_wqe *wqe, + enum ib_access_flags perms) +{ + struct siw_sge *sge = &wqe->sqe.sge[0]; + int i, len, num_sge = wqe->sqe.num_sge; + + if (unlikely(num_sge > SIW_MAX_SGE)) + return -EINVAL; + + for (i = 0, len = 0; num_sge; num_sge--, i++, sge++) { + /* + * rdma verbs: do not check stag for a zero length sge + */ + if (sge->length) { + int rv = siw_check_sge(pd, sge, &wqe->mem[i], perms, 0, + sge->length); + + if (unlikely(rv != E_ACCESS_OK)) + return rv; + } + len += sge->length; + } + return len; +} + +/* + * siw_qp_sq_proc_tx() + * + * Process one WQE which needs transmission on the wire. + */ +static int siw_qp_sq_proc_tx(struct siw_qp *qp, struct siw_wqe *wqe) +{ + struct siw_iwarp_tx *c_tx = &qp->tx_ctx; + struct socket *s = qp->attrs.sk; + int rv = 0, burst_len = qp->tx_ctx.burst; + enum rdmap_ecode ecode = RDMAP_ECODE_CATASTROPHIC_STREAM; + + if (unlikely(wqe->wr_status == SIW_WR_IDLE)) + return 0; + + if (!burst_len) + burst_len = SQ_USER_MAXBURST; + + if (wqe->wr_status == SIW_WR_QUEUED) { + if (!(wqe->sqe.flags & SIW_WQE_INLINE)) { + if (tx_type(wqe) == SIW_OP_READ_RESPONSE) + wqe->sqe.num_sge = 1; + + if (tx_type(wqe) != SIW_OP_READ && + tx_type(wqe) != SIW_OP_READ_LOCAL_INV) { + /* + * Reference memory to be tx'd w/o checking + * access for LOCAL_READ permission, since + * not defined in RDMA core. + */ + rv = siw_check_sgl_tx(qp->pd, wqe, 0); + if (rv < 0) { + if (tx_type(wqe) == + SIW_OP_READ_RESPONSE) + ecode = siw_rdmap_error(-rv); + rv = -EINVAL; + goto tx_error; + } + wqe->bytes = rv; + } else { + wqe->bytes = 0; + } + } else { + wqe->bytes = wqe->sqe.sge[0].length; + if (!qp->kernel_verbs) { + if (wqe->bytes > SIW_MAX_INLINE) { + rv = -EINVAL; + goto tx_error; + } + wqe->sqe.sge[0].laddr = (u64)&wqe->sqe.sge[1]; + } + } + wqe->wr_status = SIW_WR_INPROGRESS; + wqe->processed = 0; + + siw_update_tcpseg(c_tx, s); + + rv = siw_qp_prepare_tx(c_tx); + if (rv == PKT_FRAGMENTED) { + c_tx->state = SIW_SEND_HDR; + siw_prepare_fpdu(qp, wqe); + } else if (rv == PKT_COMPLETE) { + c_tx->state = SIW_SEND_SHORT_FPDU; + } else { + goto tx_error; + } + } + +next_segment: + siw_dbg_qp(qp, "wr type %d, state %d, data %u, sent %u, id %llx\n", + tx_type(wqe), wqe->wr_status, wqe->bytes, wqe->processed, + wqe->sqe.id); + + if (--burst_len == 0) { + rv = -EINPROGRESS; + goto tx_done; + } + if (c_tx->state == SIW_SEND_SHORT_FPDU) { + enum siw_opcode tx_type = tx_type(wqe); + unsigned int msg_flags; + + if (siw_sq_empty(qp) || !siw_tcp_nagle || burst_len == 1) + /* + * End current TCP segment, if SQ runs empty, + * or siw_tcp_nagle is not set, or we bail out + * soon due to no burst credit left. + */ + msg_flags = MSG_DONTWAIT; + else + msg_flags = MSG_DONTWAIT | MSG_MORE; + + rv = siw_tx_ctrl(c_tx, s, msg_flags); + + if (!rv && tx_type != SIW_OP_READ && + tx_type != SIW_OP_READ_LOCAL_INV) + wqe->processed = wqe->bytes; + + goto tx_done; + + } else { + rv = siw_tx_hdt(c_tx, s); + } + if (!rv) { + /* + * One segment sent. Processing completed if last + * segment, Do next segment otherwise. + */ + if (unlikely(c_tx->tx_suspend)) { + /* + * Verbs, 6.4.: Try stopping sending after a full + * DDP segment if the connection goes down + * (== peer halfclose) + */ + rv = -ECONNABORTED; + goto tx_done; + } + if (c_tx->pkt.ctrl.ddp_rdmap_ctrl & DDP_FLAG_LAST) { + siw_dbg_qp(qp, "WQE completed\n"); + goto tx_done; + } + c_tx->state = SIW_SEND_HDR; + + siw_update_tcpseg(c_tx, s); + + siw_prepare_fpdu(qp, wqe); + goto next_segment; + } +tx_done: + qp->tx_ctx.burst = burst_len; + return rv; + +tx_error: + if (ecode != RDMAP_ECODE_CATASTROPHIC_STREAM) + siw_init_terminate(qp, TERM_ERROR_LAYER_RDMAP, + RDMAP_ETYPE_REMOTE_PROTECTION, ecode, 1); + else + siw_init_terminate(qp, TERM_ERROR_LAYER_RDMAP, + RDMAP_ETYPE_CATASTROPHIC, + RDMAP_ECODE_UNSPECIFIED, 1); + return rv; +} + +static int siw_fastreg_mr(struct ib_pd *pd, struct siw_sqe *sqe) +{ + struct ib_mr *base_mr = (struct ib_mr *)sqe->base_mr; + struct siw_device *sdev = to_siw_dev(pd->device); + struct siw_mem *mem = siw_mem_id2obj(sdev, sqe->rkey >> 8); + int rv = 0; + + siw_dbg_pd(pd, "STag 0x%08x\n", sqe->rkey); + + if (unlikely(!mem || !base_mr)) { + pr_warn("siw: fastreg: STag 0x%08x unknown\n", sqe->rkey); + return -EINVAL; + } + if (unlikely(base_mr->rkey >> 8 != sqe->rkey >> 8)) { + pr_warn("siw: fastreg: STag 0x%08x: bad MR\n", sqe->rkey); + rv = -EINVAL; + goto out; + } + if (unlikely(mem->pd != pd)) { + pr_warn("siw: fastreg: PD mismatch\n"); + rv = -EINVAL; + goto out; + } + if (unlikely(mem->stag_valid)) { + pr_warn("siw: fastreg: STag 0x%08x already valid\n", sqe->rkey); + rv = -EINVAL; + goto out; + } + /* Refresh STag since user may have changed key part */ + mem->stag = sqe->rkey; + mem->perms = sqe->access; + + siw_dbg_mem(mem, "STag now valid, MR va: 0x%016llx -> 0x%016llx\n", + mem->va, base_mr->iova); + mem->va = base_mr->iova; + mem->stag_valid = 1; +out: + siw_mem_put(mem); + return rv; +} + +static int siw_qp_sq_proc_local(struct siw_qp *qp, struct siw_wqe *wqe) +{ + int rv; + + switch (tx_type(wqe)) { + case SIW_OP_REG_MR: + rv = siw_fastreg_mr(qp->pd, &wqe->sqe); + break; + + case SIW_OP_INVAL_STAG: + rv = siw_invalidate_stag(qp->pd, wqe->sqe.rkey); + break; + + default: + rv = -EINVAL; + } + return rv; +} + +/* + * siw_qp_sq_process() + * + * Core TX path routine for RDMAP/DDP/MPA using a TCP kernel socket. + * Sends RDMAP payload for the current SQ WR @wqe of @qp in one or more + * MPA FPDUs, each containing a DDP segment. + * + * SQ processing may occur in user context as a result of posting + * new WQE's or from siw_sq_work_handler() context. Processing in + * user context is limited to non-kernel verbs users. + * + * SQ processing may get paused anytime, possibly in the middle of a WR + * or FPDU, if insufficient send space is available. SQ processing + * gets resumed from siw_sq_work_handler(), if send space becomes + * available again. + * + * Must be called with the QP state read-locked. + * + * Note: + * An outbound RREQ can be satisfied by the corresponding RRESP + * _before_ it gets assigned to the ORQ. This happens regularly + * in RDMA READ via loopback case. Since both outbound RREQ and + * inbound RRESP can be handled by the same CPU, locking the ORQ + * is dead-lock prone and thus not an option. With that, the + * RREQ gets assigned to the ORQ _before_ being sent - see + * siw_activate_tx() - and pulled back in case of send failure. + */ +int siw_qp_sq_process(struct siw_qp *qp) +{ + struct siw_wqe *wqe = tx_wqe(qp); + enum siw_opcode tx_type; + unsigned long flags; + int rv = 0; + + siw_dbg_qp(qp, "enter for type %d\n", tx_type(wqe)); + +next_wqe: + /* + * Stop QP processing if SQ state changed + */ + if (unlikely(qp->tx_ctx.tx_suspend)) { + siw_dbg_qp(qp, "tx suspended\n"); + goto done; + } + tx_type = tx_type(wqe); + + if (tx_type <= SIW_OP_READ_RESPONSE) + rv = siw_qp_sq_proc_tx(qp, wqe); + else + rv = siw_qp_sq_proc_local(qp, wqe); + + if (!rv) { + /* + * WQE processing done + */ + switch (tx_type) { + case SIW_OP_SEND: + case SIW_OP_SEND_REMOTE_INV: + case SIW_OP_WRITE: + siw_wqe_put_mem(wqe, tx_type); + case SIW_OP_INVAL_STAG: + case SIW_OP_REG_MR: + if (tx_flags(wqe) & SIW_WQE_SIGNALLED) + siw_sqe_complete(qp, &wqe->sqe, wqe->bytes, + SIW_WC_SUCCESS); + break; + + case SIW_OP_READ: + case SIW_OP_READ_LOCAL_INV: + /* + * already enqueued to ORQ queue + */ + break; + + case SIW_OP_READ_RESPONSE: + siw_wqe_put_mem(wqe, tx_type); + break; + + default: + WARN(1, "undefined WQE type %d\n", tx_type); + rv = -EINVAL; + goto done; + } + + spin_lock_irqsave(&qp->sq_lock, flags); + wqe->wr_status = SIW_WR_IDLE; + rv = siw_activate_tx(qp); + spin_unlock_irqrestore(&qp->sq_lock, flags); + + if (rv <= 0) + goto done; + + goto next_wqe; + + } else if (rv == -EAGAIN) { + siw_dbg_qp(qp, "sq paused: hd/tr %d of %d, data %d\n", + qp->tx_ctx.ctrl_sent, qp->tx_ctx.ctrl_len, + qp->tx_ctx.bytes_unsent); + rv = 0; + goto done; + } else if (rv == -EINPROGRESS) { + rv = siw_sq_start(qp); + goto done; + } else { + /* + * WQE processing failed. + * Verbs 8.3.2: + * o It turns any WQE into a signalled WQE. + * o Local catastrophic error must be surfaced + * o QP must be moved into Terminate state: done by code + * doing socket state change processing + * + * o TODO: Termination message must be sent. + * o TODO: Implement more precise work completion errors, + * see enum ib_wc_status in ib_verbs.h + */ + siw_dbg_qp(qp, "wqe type %d processing failed: %d\n", + tx_type(wqe), rv); + + spin_lock_irqsave(&qp->sq_lock, flags); + /* + * RREQ may have already been completed by inbound RRESP! + */ + if (tx_type == SIW_OP_READ || + tx_type == SIW_OP_READ_LOCAL_INV) { + /* Cleanup pending entry in ORQ */ + qp->orq_put--; + qp->orq[qp->orq_put % qp->attrs.orq_size].flags = 0; + } + spin_unlock_irqrestore(&qp->sq_lock, flags); + /* + * immediately suspends further TX processing + */ + if (!qp->tx_ctx.tx_suspend) + siw_qp_cm_drop(qp, 0); + + switch (tx_type) { + case SIW_OP_SEND: + case SIW_OP_SEND_REMOTE_INV: + case SIW_OP_SEND_WITH_IMM: + case SIW_OP_WRITE: + case SIW_OP_READ: + case SIW_OP_READ_LOCAL_INV: + siw_wqe_put_mem(wqe, tx_type); + case SIW_OP_INVAL_STAG: + case SIW_OP_REG_MR: + siw_sqe_complete(qp, &wqe->sqe, wqe->bytes, + SIW_WC_LOC_QP_OP_ERR); + + siw_qp_event(qp, IB_EVENT_QP_FATAL); + + break; + + case SIW_OP_READ_RESPONSE: + siw_dbg_qp(qp, "proc. read.response failed: %d\n", rv); + + siw_qp_event(qp, IB_EVENT_QP_REQ_ERR); + + siw_wqe_put_mem(wqe, SIW_OP_READ_RESPONSE); + + break; + + default: + WARN(1, "undefined WQE type %d\n", tx_type); + rv = -EINVAL; + } + wqe->wr_status = SIW_WR_IDLE; + } +done: + return rv; +} + +static void siw_sq_resume(struct siw_qp *qp) +{ + if (down_read_trylock(&qp->state_lock)) { + if (likely(qp->attrs.state == SIW_QP_STATE_RTS && + !qp->tx_ctx.tx_suspend)) { + int rv = siw_qp_sq_process(qp); + + up_read(&qp->state_lock); + + if (unlikely(rv < 0)) { + siw_dbg_qp(qp, "SQ task failed: err %d\n", rv); + + if (!qp->tx_ctx.tx_suspend) + siw_qp_cm_drop(qp, 0); + } + } else { + up_read(&qp->state_lock); + } + } else { + siw_dbg_qp(qp, "Resume SQ while QP locked\n"); + } + siw_qp_put(qp); +} + +struct tx_task_t { + struct llist_head active; + wait_queue_head_t waiting; +}; + +static DEFINE_PER_CPU(struct tx_task_t, tx_task_g); + +void siw_stop_tx_thread(int nr_cpu) +{ + kthread_stop(siw_tx_thread[nr_cpu]); + wake_up(&per_cpu(tx_task_g, nr_cpu).waiting); +} + +int siw_run_sq(void *data) +{ + const int nr_cpu = (unsigned int)(long)data; + struct llist_node *active; + struct siw_qp *qp; + struct tx_task_t *tx_task = &per_cpu(tx_task_g, nr_cpu); + + init_llist_head(&tx_task->active); + init_waitqueue_head(&tx_task->waiting); + + pr_info("Started siw TX thread on CPU %u\n", nr_cpu); + + while (1) { + struct llist_node *fifo_list = NULL; + + wait_event_interruptible(tx_task->waiting, + !llist_empty(&tx_task->active) || + kthread_should_stop()); + + if (kthread_should_stop()) + break; + + active = llist_del_all(&tx_task->active); + /* + * llist_del_all returns a list with newest entry first. + * Re-order list for fairness among QP's. + */ + while (active) { + struct llist_node *tmp = active; + + active = llist_next(active); + tmp->next = fifo_list; + fifo_list = tmp; + } + while (fifo_list) { + qp = container_of(fifo_list, struct siw_qp, tx_list); + fifo_list = llist_next(fifo_list); + qp->tx_list.next = NULL; + + siw_sq_resume(qp); + } + } + active = llist_del_all(&tx_task->active); + if (active) { + llist_for_each_entry(qp, active, tx_list) { + qp->tx_list.next = NULL; + siw_sq_resume(qp); + } + } + pr_info("Stopped siw TX thread on CPU %u\n", nr_cpu); + + return 0; +} + +int siw_sq_start(struct siw_qp *qp) +{ + if (tx_wqe(qp)->wr_status == SIW_WR_IDLE) + return 0; + + if (unlikely(!cpu_online(qp->tx_cpu))) { + siw_put_tx_cpu(qp->tx_cpu); + qp->tx_cpu = siw_get_tx_cpu(qp->sdev); + if (qp->tx_cpu < 0) { + pr_warn("siw: no tx cpu available\n"); + + return -EIO; + } + } + siw_qp_get(qp); + + llist_add(&qp->tx_list, &per_cpu(tx_task_g, qp->tx_cpu).active); + + wake_up(&per_cpu(tx_task_g, qp->tx_cpu).waiting); + + return 0; +} |