// SPDX-License-Identifier: GPL-2.0-or-later /* RxRPC Tx data buffering. * * Copyright (C) 2022 Red Hat, Inc. All Rights Reserved. * Written by David Howells (dhowells@redhat.com) */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include <linux/slab.h> #include "ar-internal.h" static atomic_t rxrpc_txbuf_debug_ids; atomic_t rxrpc_nr_txbuf; /* * Allocate and partially initialise a data transmission buffer. */ struct rxrpc_txbuf *rxrpc_alloc_data_txbuf(struct rxrpc_call *call, size_t data_size, size_t data_align, gfp_t gfp) { struct rxrpc_wire_header *whdr; struct rxrpc_txbuf *txb; size_t total, hoff; void *buf; txb = kzalloc(sizeof(*txb), gfp); if (!txb) return NULL; hoff = round_up(sizeof(*whdr), data_align) - sizeof(*whdr); total = hoff + sizeof(*whdr) + data_size; data_align = umax(data_align, L1_CACHE_BYTES); mutex_lock(&call->conn->tx_data_alloc_lock); buf = page_frag_alloc_align(&call->conn->tx_data_alloc, total, gfp, data_align); mutex_unlock(&call->conn->tx_data_alloc_lock); if (!buf) { kfree(txb); return NULL; } whdr = buf + hoff; refcount_set(&txb->ref, 1); txb->call_debug_id = call->debug_id; txb->debug_id = atomic_inc_return(&rxrpc_txbuf_debug_ids); txb->alloc_size = data_size; txb->space = data_size; txb->offset = sizeof(*whdr); txb->flags = call->conn->out_clientflag; txb->seq = call->send_top + 1; txb->nr_kvec = 1; txb->kvec[0].iov_base = whdr; txb->kvec[0].iov_len = sizeof(*whdr); whdr->epoch = htonl(call->conn->proto.epoch); whdr->cid = htonl(call->cid); whdr->callNumber = htonl(call->call_id); whdr->seq = htonl(txb->seq); whdr->type = RXRPC_PACKET_TYPE_DATA; whdr->flags = 0; whdr->userStatus = 0; whdr->securityIndex = call->security_ix; whdr->_rsvd = 0; whdr->serviceId = htons(call->dest_srx.srx_service); trace_rxrpc_txbuf(txb->debug_id, txb->call_debug_id, txb->seq, 1, rxrpc_txbuf_alloc_data); atomic_inc(&rxrpc_nr_txbuf); return txb; } void rxrpc_get_txbuf(struct rxrpc_txbuf *txb, enum rxrpc_txbuf_trace what) { int r; __refcount_inc(&txb->ref, &r); trace_rxrpc_txbuf(txb->debug_id, txb->call_debug_id, txb->seq, r + 1, what); } void rxrpc_see_txbuf(struct rxrpc_txbuf *txb, enum rxrpc_txbuf_trace what) { int r = refcount_read(&txb->ref); trace_rxrpc_txbuf(txb->debug_id, txb->call_debug_id, txb->seq, r, what); } static void rxrpc_free_txbuf(struct rxrpc_txbuf *txb) { int i; trace_rxrpc_txbuf(txb->debug_id, txb->call_debug_id, txb->seq, 0, rxrpc_txbuf_free); for (i = 0; i < txb->nr_kvec; i++) if (txb->kvec[i].iov_base && !is_zero_pfn(page_to_pfn(virt_to_page(txb->kvec[i].iov_base)))) page_frag_free(txb->kvec[i].iov_base); kfree(txb); atomic_dec(&rxrpc_nr_txbuf); } void rxrpc_put_txbuf(struct rxrpc_txbuf *txb, enum rxrpc_txbuf_trace what) { unsigned int debug_id, call_debug_id; rxrpc_seq_t seq; bool dead; int r; if (txb) { debug_id = txb->debug_id; call_debug_id = txb->call_debug_id; seq = txb->seq; dead = __refcount_dec_and_test(&txb->ref, &r); trace_rxrpc_txbuf(debug_id, call_debug_id, seq, r - 1, what); if (dead) rxrpc_free_txbuf(txb); } }