Index: vendor-sys/ena-com/dist/ena_eth_com.c =================================================================== --- vendor-sys/ena-com/dist/ena_eth_com.c (revision 343070) +++ vendor-sys/ena-com/dist/ena_eth_com.c (revision 343071) @@ -1,624 +1,624 @@ /*- * BSD LICENSE * * Copyright (c) 2015-2017 Amazon.com, Inc. or its affiliates. * All rights reserved. * * 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. * * Neither the name of copyright holder nor the names of its * contributors may be used to endorse or promote products derived * from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ #include "ena_eth_com.h" static inline struct ena_eth_io_rx_cdesc_base *ena_com_get_next_rx_cdesc( struct ena_com_io_cq *io_cq) { struct ena_eth_io_rx_cdesc_base *cdesc; u16 expected_phase, head_masked; u16 desc_phase; head_masked = io_cq->head & (io_cq->q_depth - 1); expected_phase = io_cq->phase; cdesc = (struct ena_eth_io_rx_cdesc_base *)(io_cq->cdesc_addr.virt_addr + (head_masked * io_cq->cdesc_entry_size_in_bytes)); desc_phase = (READ_ONCE(cdesc->status) & ENA_ETH_IO_RX_CDESC_BASE_PHASE_MASK) >> ENA_ETH_IO_RX_CDESC_BASE_PHASE_SHIFT; if (desc_phase != expected_phase) return NULL; return cdesc; } static inline void ena_com_cq_inc_head(struct ena_com_io_cq *io_cq) { io_cq->head++; /* Switch phase bit in case of wrap around */ if (unlikely((io_cq->head & (io_cq->q_depth - 1)) == 0)) io_cq->phase ^= 1; } static inline void *get_sq_desc_regular_queue(struct ena_com_io_sq *io_sq) { u16 tail_masked; u32 offset; tail_masked = io_sq->tail & (io_sq->q_depth - 1); offset = tail_masked * io_sq->desc_entry_size; return (void *)((uintptr_t)io_sq->desc_addr.virt_addr + offset); } static inline void ena_com_write_bounce_buffer_to_dev(struct ena_com_io_sq *io_sq, u8 *bounce_buffer) { struct ena_com_llq_info *llq_info = &io_sq->llq_info; u16 dst_tail_mask; u32 dst_offset; dst_tail_mask = io_sq->tail & (io_sq->q_depth - 1); dst_offset = dst_tail_mask * llq_info->desc_list_entry_size; /* Make sure everything was written into the bounce buffer before * writing the bounce buffer to the device */ wmb(); /* The line is completed. Copy it to dev */ ENA_MEMCPY_TO_DEVICE_64(io_sq->desc_addr.pbuf_dev_addr + dst_offset, bounce_buffer, llq_info->desc_list_entry_size); io_sq->tail++; /* Switch phase bit in case of wrap around */ if (unlikely((io_sq->tail & (io_sq->q_depth - 1)) == 0)) io_sq->phase ^= 1; } static inline int ena_com_write_header_to_bounce(struct ena_com_io_sq *io_sq, u8 *header_src, u16 header_len) { struct ena_com_llq_pkt_ctrl *pkt_ctrl = &io_sq->llq_buf_ctrl; struct ena_com_llq_info *llq_info = &io_sq->llq_info; u8 *bounce_buffer = pkt_ctrl->curr_bounce_buf; u16 header_offset; if (io_sq->mem_queue_type == ENA_ADMIN_PLACEMENT_POLICY_HOST) return 0; header_offset = llq_info->descs_num_before_header * io_sq->desc_entry_size; if (unlikely((header_offset + header_len) > llq_info->desc_list_entry_size)) { ena_trc_err("trying to write header larger than llq entry can accommodate\n"); return ENA_COM_FAULT; } if (unlikely(!bounce_buffer)) { ena_trc_err("bounce buffer is NULL\n"); return ENA_COM_FAULT; } memcpy(bounce_buffer + header_offset, header_src, header_len); return 0; } static inline void *get_sq_desc_llq(struct ena_com_io_sq *io_sq) { struct ena_com_llq_pkt_ctrl *pkt_ctrl = &io_sq->llq_buf_ctrl; u8 *bounce_buffer; void *sq_desc; bounce_buffer = pkt_ctrl->curr_bounce_buf; if (unlikely(!bounce_buffer)) { ena_trc_err("bounce buffer is NULL\n"); return NULL; } sq_desc = bounce_buffer + pkt_ctrl->idx * io_sq->desc_entry_size; pkt_ctrl->idx++; pkt_ctrl->descs_left_in_line--; return sq_desc; } static inline void ena_com_close_bounce_buffer(struct ena_com_io_sq *io_sq) { struct ena_com_llq_pkt_ctrl *pkt_ctrl = &io_sq->llq_buf_ctrl; struct ena_com_llq_info *llq_info = &io_sq->llq_info; if (io_sq->mem_queue_type == ENA_ADMIN_PLACEMENT_POLICY_HOST) return; /* bounce buffer was used, so write it and get a new one */ if (pkt_ctrl->idx) { ena_com_write_bounce_buffer_to_dev(io_sq, pkt_ctrl->curr_bounce_buf); pkt_ctrl->curr_bounce_buf = ena_com_get_next_bounce_buffer(&io_sq->bounce_buf_ctrl); memset(io_sq->llq_buf_ctrl.curr_bounce_buf, 0x0, llq_info->desc_list_entry_size); } pkt_ctrl->idx = 0; pkt_ctrl->descs_left_in_line = llq_info->descs_num_before_header; } static inline void *get_sq_desc(struct ena_com_io_sq *io_sq) { if (io_sq->mem_queue_type == ENA_ADMIN_PLACEMENT_POLICY_DEV) return get_sq_desc_llq(io_sq); return get_sq_desc_regular_queue(io_sq); } static inline void ena_com_sq_update_llq_tail(struct ena_com_io_sq *io_sq) { struct ena_com_llq_pkt_ctrl *pkt_ctrl = &io_sq->llq_buf_ctrl; struct ena_com_llq_info *llq_info = &io_sq->llq_info; if (!pkt_ctrl->descs_left_in_line) { ena_com_write_bounce_buffer_to_dev(io_sq, pkt_ctrl->curr_bounce_buf); pkt_ctrl->curr_bounce_buf = ena_com_get_next_bounce_buffer(&io_sq->bounce_buf_ctrl); memset(io_sq->llq_buf_ctrl.curr_bounce_buf, 0x0, llq_info->desc_list_entry_size); pkt_ctrl->idx = 0; if (llq_info->desc_stride_ctrl == ENA_ADMIN_SINGLE_DESC_PER_ENTRY) pkt_ctrl->descs_left_in_line = 1; else pkt_ctrl->descs_left_in_line = llq_info->desc_list_entry_size / io_sq->desc_entry_size; } } static inline void ena_com_sq_update_tail(struct ena_com_io_sq *io_sq) { if (io_sq->mem_queue_type == ENA_ADMIN_PLACEMENT_POLICY_DEV) { ena_com_sq_update_llq_tail(io_sq); return; } io_sq->tail++; /* Switch phase bit in case of wrap around */ if (unlikely((io_sq->tail & (io_sq->q_depth - 1)) == 0)) io_sq->phase ^= 1; } static inline struct ena_eth_io_rx_cdesc_base * ena_com_rx_cdesc_idx_to_ptr(struct ena_com_io_cq *io_cq, u16 idx) { idx &= (io_cq->q_depth - 1); return (struct ena_eth_io_rx_cdesc_base *) ((uintptr_t)io_cq->cdesc_addr.virt_addr + idx * io_cq->cdesc_entry_size_in_bytes); } static inline u16 ena_com_cdesc_rx_pkt_get(struct ena_com_io_cq *io_cq, u16 *first_cdesc_idx) { struct ena_eth_io_rx_cdesc_base *cdesc; u16 count = 0, head_masked; u32 last = 0; do { cdesc = ena_com_get_next_rx_cdesc(io_cq); if (!cdesc) break; ena_com_cq_inc_head(io_cq); count++; last = (READ_ONCE(cdesc->status) & ENA_ETH_IO_RX_CDESC_BASE_LAST_MASK) >> ENA_ETH_IO_RX_CDESC_BASE_LAST_SHIFT; } while (!last); if (last) { *first_cdesc_idx = io_cq->cur_rx_pkt_cdesc_start_idx; count += io_cq->cur_rx_pkt_cdesc_count; head_masked = io_cq->head & (io_cq->q_depth - 1); io_cq->cur_rx_pkt_cdesc_count = 0; io_cq->cur_rx_pkt_cdesc_start_idx = head_masked; ena_trc_dbg("ena q_id: %d packets were completed. first desc idx %u descs# %d\n", io_cq->qid, *first_cdesc_idx, count); } else { io_cq->cur_rx_pkt_cdesc_count += count; count = 0; } return count; } static inline bool ena_com_meta_desc_changed(struct ena_com_io_sq *io_sq, struct ena_com_tx_ctx *ena_tx_ctx) { int rc; if (ena_tx_ctx->meta_valid) { rc = memcmp(&io_sq->cached_tx_meta, &ena_tx_ctx->ena_meta, sizeof(struct ena_com_tx_meta)); if (unlikely(rc != 0)) return true; } return false; } static inline void ena_com_create_and_store_tx_meta_desc(struct ena_com_io_sq *io_sq, struct ena_com_tx_ctx *ena_tx_ctx) { struct ena_eth_io_tx_meta_desc *meta_desc = NULL; struct ena_com_tx_meta *ena_meta = &ena_tx_ctx->ena_meta; meta_desc = get_sq_desc(io_sq); memset(meta_desc, 0x0, sizeof(struct ena_eth_io_tx_meta_desc)); meta_desc->len_ctrl |= ENA_ETH_IO_TX_META_DESC_META_DESC_MASK; meta_desc->len_ctrl |= ENA_ETH_IO_TX_META_DESC_EXT_VALID_MASK; /* bits 0-9 of the mss */ meta_desc->word2 |= (ena_meta->mss << ENA_ETH_IO_TX_META_DESC_MSS_LO_SHIFT) & ENA_ETH_IO_TX_META_DESC_MSS_LO_MASK; /* bits 10-13 of the mss */ meta_desc->len_ctrl |= ((ena_meta->mss >> 10) << ENA_ETH_IO_TX_META_DESC_MSS_HI_SHIFT) & ENA_ETH_IO_TX_META_DESC_MSS_HI_MASK; /* Extended meta desc */ meta_desc->len_ctrl |= ENA_ETH_IO_TX_META_DESC_ETH_META_TYPE_MASK; meta_desc->len_ctrl |= ENA_ETH_IO_TX_META_DESC_META_STORE_MASK; meta_desc->len_ctrl |= (io_sq->phase << ENA_ETH_IO_TX_META_DESC_PHASE_SHIFT) & ENA_ETH_IO_TX_META_DESC_PHASE_MASK; meta_desc->len_ctrl |= ENA_ETH_IO_TX_META_DESC_FIRST_MASK; meta_desc->word2 |= ena_meta->l3_hdr_len & ENA_ETH_IO_TX_META_DESC_L3_HDR_LEN_MASK; meta_desc->word2 |= (ena_meta->l3_hdr_offset << ENA_ETH_IO_TX_META_DESC_L3_HDR_OFF_SHIFT) & ENA_ETH_IO_TX_META_DESC_L3_HDR_OFF_MASK; meta_desc->word2 |= (ena_meta->l4_hdr_len << ENA_ETH_IO_TX_META_DESC_L4_HDR_LEN_IN_WORDS_SHIFT) & ENA_ETH_IO_TX_META_DESC_L4_HDR_LEN_IN_WORDS_MASK; meta_desc->len_ctrl |= ENA_ETH_IO_TX_META_DESC_META_STORE_MASK; /* Cached the meta desc */ memcpy(&io_sq->cached_tx_meta, ena_meta, sizeof(struct ena_com_tx_meta)); ena_com_sq_update_tail(io_sq); } static inline void ena_com_rx_set_flags(struct ena_com_rx_ctx *ena_rx_ctx, struct ena_eth_io_rx_cdesc_base *cdesc) { ena_rx_ctx->l3_proto = cdesc->status & ENA_ETH_IO_RX_CDESC_BASE_L3_PROTO_IDX_MASK; ena_rx_ctx->l4_proto = (cdesc->status & ENA_ETH_IO_RX_CDESC_BASE_L4_PROTO_IDX_MASK) >> ENA_ETH_IO_RX_CDESC_BASE_L4_PROTO_IDX_SHIFT; ena_rx_ctx->l3_csum_err = (cdesc->status & ENA_ETH_IO_RX_CDESC_BASE_L3_CSUM_ERR_MASK) >> ENA_ETH_IO_RX_CDESC_BASE_L3_CSUM_ERR_SHIFT; ena_rx_ctx->l4_csum_err = (cdesc->status & ENA_ETH_IO_RX_CDESC_BASE_L4_CSUM_ERR_MASK) >> ENA_ETH_IO_RX_CDESC_BASE_L4_CSUM_ERR_SHIFT; ena_rx_ctx->hash = cdesc->hash; ena_rx_ctx->frag = (cdesc->status & ENA_ETH_IO_RX_CDESC_BASE_IPV4_FRAG_MASK) >> ENA_ETH_IO_RX_CDESC_BASE_IPV4_FRAG_SHIFT; ena_trc_dbg("ena_rx_ctx->l3_proto %d ena_rx_ctx->l4_proto %d\nena_rx_ctx->l3_csum_err %d ena_rx_ctx->l4_csum_err %d\nhash frag %d frag: %d cdesc_status: %x\n", ena_rx_ctx->l3_proto, ena_rx_ctx->l4_proto, ena_rx_ctx->l3_csum_err, ena_rx_ctx->l4_csum_err, ena_rx_ctx->hash, ena_rx_ctx->frag, cdesc->status); } /*****************************************************************************/ /***************************** API **********************************/ /*****************************************************************************/ int ena_com_prepare_tx(struct ena_com_io_sq *io_sq, struct ena_com_tx_ctx *ena_tx_ctx, int *nb_hw_desc) { struct ena_eth_io_tx_desc *desc = NULL; struct ena_com_buf *ena_bufs = ena_tx_ctx->ena_bufs; void *buffer_to_push = ena_tx_ctx->push_header; u16 header_len = ena_tx_ctx->header_len; u16 num_bufs = ena_tx_ctx->num_bufs; u16 start_tail = io_sq->tail; int i, rc; bool have_meta; u64 addr_hi; ENA_WARN(io_sq->direction != ENA_COM_IO_QUEUE_DIRECTION_TX, "wrong Q type"); /* num_bufs +1 for potential meta desc */ if (!ena_com_sq_have_enough_space(io_sq, num_bufs + 1)) { - ena_trc_err("Not enough space in the tx queue\n"); + ena_trc_dbg("Not enough space in the tx queue\n"); return ENA_COM_NO_MEM; } if (unlikely(header_len > io_sq->tx_max_header_size)) { ena_trc_err("header size is too large %d max header: %d\n", header_len, io_sq->tx_max_header_size); return ENA_COM_INVAL; } if (unlikely((io_sq->mem_queue_type == ENA_ADMIN_PLACEMENT_POLICY_DEV) && !buffer_to_push)) return ENA_COM_INVAL; rc = ena_com_write_header_to_bounce(io_sq, buffer_to_push, header_len); if (unlikely(rc)) return rc; have_meta = ena_tx_ctx->meta_valid && ena_com_meta_desc_changed(io_sq, ena_tx_ctx); if (have_meta) ena_com_create_and_store_tx_meta_desc(io_sq, ena_tx_ctx); /* If the caller doesn't want send packets */ if (unlikely(!num_bufs && !header_len)) { ena_com_close_bounce_buffer(io_sq); *nb_hw_desc = io_sq->tail - start_tail; return 0; } desc = get_sq_desc(io_sq); if (unlikely(!desc)) return ENA_COM_FAULT; memset(desc, 0x0, sizeof(struct ena_eth_io_tx_desc)); /* Set first desc when we don't have meta descriptor */ if (!have_meta) desc->len_ctrl |= ENA_ETH_IO_TX_DESC_FIRST_MASK; desc->buff_addr_hi_hdr_sz |= (header_len << ENA_ETH_IO_TX_DESC_HEADER_LENGTH_SHIFT) & ENA_ETH_IO_TX_DESC_HEADER_LENGTH_MASK; desc->len_ctrl |= (io_sq->phase << ENA_ETH_IO_TX_DESC_PHASE_SHIFT) & ENA_ETH_IO_TX_DESC_PHASE_MASK; desc->len_ctrl |= ENA_ETH_IO_TX_DESC_COMP_REQ_MASK; /* Bits 0-9 */ desc->meta_ctrl |= (ena_tx_ctx->req_id << ENA_ETH_IO_TX_DESC_REQ_ID_LO_SHIFT) & ENA_ETH_IO_TX_DESC_REQ_ID_LO_MASK; desc->meta_ctrl |= (ena_tx_ctx->df << ENA_ETH_IO_TX_DESC_DF_SHIFT) & ENA_ETH_IO_TX_DESC_DF_MASK; /* Bits 10-15 */ desc->len_ctrl |= ((ena_tx_ctx->req_id >> 10) << ENA_ETH_IO_TX_DESC_REQ_ID_HI_SHIFT) & ENA_ETH_IO_TX_DESC_REQ_ID_HI_MASK; if (ena_tx_ctx->meta_valid) { desc->meta_ctrl |= (ena_tx_ctx->tso_enable << ENA_ETH_IO_TX_DESC_TSO_EN_SHIFT) & ENA_ETH_IO_TX_DESC_TSO_EN_MASK; desc->meta_ctrl |= ena_tx_ctx->l3_proto & ENA_ETH_IO_TX_DESC_L3_PROTO_IDX_MASK; desc->meta_ctrl |= (ena_tx_ctx->l4_proto << ENA_ETH_IO_TX_DESC_L4_PROTO_IDX_SHIFT) & ENA_ETH_IO_TX_DESC_L4_PROTO_IDX_MASK; desc->meta_ctrl |= (ena_tx_ctx->l3_csum_enable << ENA_ETH_IO_TX_DESC_L3_CSUM_EN_SHIFT) & ENA_ETH_IO_TX_DESC_L3_CSUM_EN_MASK; desc->meta_ctrl |= (ena_tx_ctx->l4_csum_enable << ENA_ETH_IO_TX_DESC_L4_CSUM_EN_SHIFT) & ENA_ETH_IO_TX_DESC_L4_CSUM_EN_MASK; desc->meta_ctrl |= (ena_tx_ctx->l4_csum_partial << ENA_ETH_IO_TX_DESC_L4_CSUM_PARTIAL_SHIFT) & ENA_ETH_IO_TX_DESC_L4_CSUM_PARTIAL_MASK; } for (i = 0; i < num_bufs; i++) { /* The first desc share the same desc as the header */ if (likely(i != 0)) { ena_com_sq_update_tail(io_sq); desc = get_sq_desc(io_sq); if (unlikely(!desc)) return ENA_COM_FAULT; memset(desc, 0x0, sizeof(struct ena_eth_io_tx_desc)); desc->len_ctrl |= (io_sq->phase << ENA_ETH_IO_TX_DESC_PHASE_SHIFT) & ENA_ETH_IO_TX_DESC_PHASE_MASK; } desc->len_ctrl |= ena_bufs->len & ENA_ETH_IO_TX_DESC_LENGTH_MASK; addr_hi = ((ena_bufs->paddr & GENMASK_ULL(io_sq->dma_addr_bits - 1, 32)) >> 32); desc->buff_addr_lo = (u32)ena_bufs->paddr; desc->buff_addr_hi_hdr_sz |= addr_hi & ENA_ETH_IO_TX_DESC_ADDR_HI_MASK; ena_bufs++; } /* set the last desc indicator */ desc->len_ctrl |= ENA_ETH_IO_TX_DESC_LAST_MASK; ena_com_sq_update_tail(io_sq); ena_com_close_bounce_buffer(io_sq); *nb_hw_desc = io_sq->tail - start_tail; return 0; } int ena_com_rx_pkt(struct ena_com_io_cq *io_cq, struct ena_com_io_sq *io_sq, struct ena_com_rx_ctx *ena_rx_ctx) { struct ena_com_rx_buf_info *ena_buf = &ena_rx_ctx->ena_bufs[0]; struct ena_eth_io_rx_cdesc_base *cdesc = NULL; u16 cdesc_idx = 0; u16 nb_hw_desc; u16 i; ENA_WARN(io_cq->direction != ENA_COM_IO_QUEUE_DIRECTION_RX, "wrong Q type"); nb_hw_desc = ena_com_cdesc_rx_pkt_get(io_cq, &cdesc_idx); if (nb_hw_desc == 0) { ena_rx_ctx->descs = nb_hw_desc; return 0; } ena_trc_dbg("fetch rx packet: queue %d completed desc: %d\n", io_cq->qid, nb_hw_desc); if (unlikely(nb_hw_desc > ena_rx_ctx->max_bufs)) { ena_trc_err("Too many RX cdescs (%d) > MAX(%d)\n", nb_hw_desc, ena_rx_ctx->max_bufs); return ENA_COM_NO_SPACE; } for (i = 0; i < nb_hw_desc; i++) { cdesc = ena_com_rx_cdesc_idx_to_ptr(io_cq, cdesc_idx + i); ena_buf->len = cdesc->length; ena_buf->req_id = cdesc->req_id; ena_buf++; } /* Update SQ head ptr */ io_sq->next_to_comp += nb_hw_desc; ena_trc_dbg("[%s][QID#%d] Updating SQ head to: %d\n", __func__, io_sq->qid, io_sq->next_to_comp); /* Get rx flags from the last pkt */ ena_com_rx_set_flags(ena_rx_ctx, cdesc); ena_rx_ctx->descs = nb_hw_desc; return 0; } int ena_com_add_single_rx_desc(struct ena_com_io_sq *io_sq, struct ena_com_buf *ena_buf, u16 req_id) { struct ena_eth_io_rx_desc *desc; ENA_WARN(io_sq->direction != ENA_COM_IO_QUEUE_DIRECTION_RX, "wrong Q type"); if (unlikely(!ena_com_sq_have_enough_space(io_sq, 1))) return ENA_COM_NO_SPACE; desc = get_sq_desc(io_sq); if (unlikely(!desc)) return ENA_COM_FAULT; memset(desc, 0x0, sizeof(struct ena_eth_io_rx_desc)); desc->length = ena_buf->len; desc->ctrl |= ENA_ETH_IO_RX_DESC_FIRST_MASK; desc->ctrl |= ENA_ETH_IO_RX_DESC_LAST_MASK; desc->ctrl |= io_sq->phase & ENA_ETH_IO_RX_DESC_PHASE_MASK; desc->ctrl |= ENA_ETH_IO_RX_DESC_COMP_REQ_MASK; desc->req_id = req_id; desc->buff_addr_lo = (u32)ena_buf->paddr; desc->buff_addr_hi = ((ena_buf->paddr & GENMASK_ULL(io_sq->dma_addr_bits - 1, 32)) >> 32); ena_com_sq_update_tail(io_sq); return 0; } int ena_com_tx_comp_req_id_get(struct ena_com_io_cq *io_cq, u16 *req_id) { u8 expected_phase, cdesc_phase; struct ena_eth_io_tx_cdesc *cdesc; u16 masked_head; masked_head = io_cq->head & (io_cq->q_depth - 1); expected_phase = io_cq->phase; cdesc = (struct ena_eth_io_tx_cdesc *) ((uintptr_t)io_cq->cdesc_addr.virt_addr + (masked_head * io_cq->cdesc_entry_size_in_bytes)); /* When the current completion descriptor phase isn't the same as the * expected, it mean that the device still didn't update * this completion. */ cdesc_phase = READ_ONCE(cdesc->flags) & ENA_ETH_IO_TX_CDESC_PHASE_MASK; if (cdesc_phase != expected_phase) return ENA_COM_TRY_AGAIN; if (unlikely(cdesc->req_id >= io_cq->q_depth)) { ena_trc_err("Invalid req id %d\n", cdesc->req_id); return ENA_COM_INVAL; } ena_com_cq_inc_head(io_cq); *req_id = READ_ONCE(cdesc->req_id); return 0; }