/* *------------------------------------------------------------------ * Copyright (c) 2018 Cisco and/or its affiliates. * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at: * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. *------------------------------------------------------------------ */ #include <vlib/vlib.h> #include <vlib/unix/unix.h> #include <vlib/pci/pci.h> #include <vnet/ethernet/ethernet.h> #include <vnet/devices/devices.h> #include <vmxnet3/vmxnet3.h> static_always_inline void vmxnet3_tx_comp_ring_advance_next (vmxnet3_txq_t * txq) { vmxnet3_tx_comp_ring *comp_ring = &txq->tx_comp_ring; comp_ring->next++; if (PREDICT_FALSE (comp_ring->next == txq->size)) { comp_ring->next = 0; comp_ring->gen ^= VMXNET3_TXCF_GEN; } } static_always_inline void vmxnet3_tx_ring_advance_produce (vmxnet3_txq_t * txq) { txq->tx_ring.produce++; if (PREDICT_FALSE (txq->tx_ring.produce == txq->size)) { txq->tx_ring.produce = 0; txq->tx_ring.gen ^= VMXNET3_TXF_GEN; } } static_always_inline void vmxnet3_tx_ring_advance_consume (vmxnet3_txq_t * txq) { txq->tx_ring.consume++; txq->tx_ring.consume &= txq->size - 1; } static_always_inline void vmxnet3_txq_release (vlib_main_t * vm, vmxnet3_device_t * vd, vmxnet3_txq_t * txq) { vmxnet3_tx_comp *tx_comp; vmxnet3_tx_comp_ring *comp_ring; comp_ring = &txq->tx_comp_ring; tx_comp = &txq->tx_comp[comp_ring->next]; while ((tx_comp->flags & VMXNET3_TXCF_GEN) == comp_ring->gen) { u16 eop_idx = tx_comp->index & VMXNET3_TXC_INDEX; u32 bi0 = txq->tx_ring.bufs[txq->tx_ring.consume]; vlib_buffer_free_one (vm, bi0); while (txq->tx_ring.consume != eop_idx) { vmxnet3_tx_ring_advance_consume (txq); } vmxnet3_tx_ring_advance_consume (txq); vmxnet3_tx_comp_ring_advance_next (txq); tx_comp = &txq->tx_comp[comp_ring->next]; } } static_always_inline u16 vmxnet3_tx_ring_space_left (vmxnet3_txq_t * txq) { u16 count; count = (txq->tx_ring.consume - txq->tx_ring.produce - 1); /* Wrapped? */ if (txq->tx_ring.produce >= txq->tx_ring.consume) count += txq->size; return count; } VNET_DEVICE_CLASS_TX_FN (vmxnet3_device_class) (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame) { vmxnet3_main_t *vmxm = &vmxnet3_main; vnet_interface_output_runtime_t *rd = (void *) node->runtime_data; vmxnet3_device_t *vd = pool_elt_at_index (vmxm->devices, rd->dev_instance); u32 *buffers = vlib_frame_vector_args (frame); u32 bi0; vlib_buffer_t *b0; vmxnet3_tx_desc *txd = 0; u32 desc_idx, generation, first_idx; u16 space_left; u16 n_left = frame->n_vectors; vmxnet3_txq_t *txq; u32 thread_index = vm->thread_index; u16 qid = thread_index, produce; if (PREDICT_FALSE (!(vd->flags & VMXNET3_DEVICE_F_LINK_UP))) { vlib_buffer_free (vm, buffers, n_left); vlib_error_count (vm, node->node_index, VMXNET3_TX_ERROR_LINK_DOWN, n_left); return (0); } txq = vec_elt_at_index (vd->txqs, qid % vd->num_tx_queues); clib_spinlock_lock_if_init (&txq->lock); vmxnet3_txq_release (vm, vd, txq); produce = txq->tx_ring.produce; while (PREDICT_TRUE (n_left)) { u16 space_needed = 1, i; vlib_buffer_t *b; bi0 = buffers[0]; b0 = vlib_get_buffer (vm, bi0); b = b0; space_left = vmxnet3_tx_ring_space_left (txq); while (b->flags & VLIB_BUFFER_NEXT_PRESENT) { u32 next_buffer = b->next_buffer; b = vlib_get_buffer (vm, next_buffer); space_needed++; } if (PREDICT_FALSE (space_left < space_needed)) { vmxnet3_txq_release (vm, vd, txq); space_left = vmxnet3_tx_ring_space_left (txq); if (PREDICT_FALSE (space_left < space_needed)) { vlib_buffer_free_one (vm, bi0); vlib_error_count (vm, node->node_index, VMXNET3_TX_ERROR_NO_FREE_SLOTS, 1); buffers++; n_left--; /* * Drop this packet. But we may have enough room for the next * packet */ continue; } } /* * Toggle the generation bit for SOP fragment to avoid device starts * reading incomplete packet */ generation = txq->tx_ring.gen ^ VMXNET3_TXF_GEN; first_idx = txq->tx_ring.produce; for (i = 0; i < space_needed; i++) { b0 = vlib_get_buffer (vm, bi0); VLIB_BUFFER_TRACE_TRAJECTORY_INIT (b0); desc_idx = txq->tx_ring.produce; vmxnet3_tx_ring_advance_produce (txq); txq->tx_ring.bufs[desc_idx] = bi0; txd = &txq->tx_desc[desc_idx]; txd->address = vlib_buffer_get_current_pa (vm, b0); txd->flags[0] = generation | b0->current_length; generation = txq->tx_ring.gen; txd->flags[1] = 0; bi0 = b0->next_buffer; } txd->flags[1] = VMXNET3_TXF_CQ | VMXNET3_TXF_EOP; asm volatile ("":::"memory"); /* * Now toggle back the generation bit for the first segment. * Device can start reading the packet */ txq->tx_desc[first_idx].flags[0] ^= VMXNET3_TXF_GEN; buffers++; n_left--; } if (PREDICT_TRUE (produce != txq->tx_ring.produce)) vmxnet3_reg_write_inline (vd, 0, VMXNET3_REG_TXPROD, txq->tx_ring.produce); clib_spinlock_unlock_if_init (&txq->lock); return (frame->n_vectors - n_left); } /* * fd.io coding-style-patch-verification: ON * * Local Variables: * eval: (c-set-style "gnu") * End: */