David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 1 | /* RxRPC recvmsg() implementation |
| 2 | * |
| 3 | * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved. |
| 4 | * Written by David Howells (dhowells@redhat.com) |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or |
| 7 | * modify it under the terms of the GNU General Public License |
| 8 | * as published by the Free Software Foundation; either version |
| 9 | * 2 of the License, or (at your option) any later version. |
| 10 | */ |
| 11 | |
Joe Perches | 9b6d539 | 2016-06-02 12:08:52 -0700 | [diff] [blame] | 12 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
| 13 | |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 14 | #include <linux/net.h> |
| 15 | #include <linux/skbuff.h> |
Paul Gortmaker | bc3b2d7 | 2011-07-15 11:47:34 -0400 | [diff] [blame] | 16 | #include <linux/export.h> |
Ingo Molnar | 174cd4b | 2017-02-02 19:15:33 +0100 | [diff] [blame] | 17 | #include <linux/sched/signal.h> |
| 18 | |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 19 | #include <net/sock.h> |
| 20 | #include <net/af_rxrpc.h> |
| 21 | #include "ar-internal.h" |
| 22 | |
| 23 | /* |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 24 | * Post a call for attention by the socket or kernel service. Further |
| 25 | * notifications are suppressed by putting recvmsg_link on a dummy queue. |
| 26 | */ |
| 27 | void rxrpc_notify_socket(struct rxrpc_call *call) |
| 28 | { |
| 29 | struct rxrpc_sock *rx; |
| 30 | struct sock *sk; |
| 31 | |
| 32 | _enter("%d", call->debug_id); |
| 33 | |
| 34 | if (!list_empty(&call->recvmsg_link)) |
| 35 | return; |
| 36 | |
| 37 | rcu_read_lock(); |
| 38 | |
| 39 | rx = rcu_dereference(call->socket); |
| 40 | sk = &rx->sk; |
| 41 | if (rx && sk->sk_state < RXRPC_CLOSE) { |
| 42 | if (call->notify_rx) { |
David Howells | 20acbd9 | 2017-11-02 15:06:08 +0000 | [diff] [blame] | 43 | spin_lock_bh(&call->notify_lock); |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 44 | call->notify_rx(sk, call, call->user_call_ID); |
David Howells | 20acbd9 | 2017-11-02 15:06:08 +0000 | [diff] [blame] | 45 | spin_unlock_bh(&call->notify_lock); |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 46 | } else { |
| 47 | write_lock_bh(&rx->recvmsg_lock); |
| 48 | if (list_empty(&call->recvmsg_link)) { |
| 49 | rxrpc_get_call(call, rxrpc_call_got); |
| 50 | list_add_tail(&call->recvmsg_link, &rx->recvmsg_q); |
| 51 | } |
| 52 | write_unlock_bh(&rx->recvmsg_lock); |
| 53 | |
| 54 | if (!sock_flag(sk, SOCK_DEAD)) { |
| 55 | _debug("call %ps", sk->sk_data_ready); |
| 56 | sk->sk_data_ready(sk); |
| 57 | } |
| 58 | } |
| 59 | } |
| 60 | |
| 61 | rcu_read_unlock(); |
| 62 | _leave(""); |
| 63 | } |
| 64 | |
| 65 | /* |
| 66 | * Pass a call terminating message to userspace. |
| 67 | */ |
| 68 | static int rxrpc_recvmsg_term(struct rxrpc_call *call, struct msghdr *msg) |
| 69 | { |
| 70 | u32 tmp = 0; |
| 71 | int ret; |
| 72 | |
| 73 | switch (call->completion) { |
| 74 | case RXRPC_CALL_SUCCEEDED: |
| 75 | ret = 0; |
| 76 | if (rxrpc_is_service_call(call)) |
| 77 | ret = put_cmsg(msg, SOL_RXRPC, RXRPC_ACK, 0, &tmp); |
| 78 | break; |
| 79 | case RXRPC_CALL_REMOTELY_ABORTED: |
| 80 | tmp = call->abort_code; |
| 81 | ret = put_cmsg(msg, SOL_RXRPC, RXRPC_ABORT, 4, &tmp); |
| 82 | break; |
| 83 | case RXRPC_CALL_LOCALLY_ABORTED: |
| 84 | tmp = call->abort_code; |
| 85 | ret = put_cmsg(msg, SOL_RXRPC, RXRPC_ABORT, 4, &tmp); |
| 86 | break; |
| 87 | case RXRPC_CALL_NETWORK_ERROR: |
David Howells | 3a92789 | 2017-04-06 10:11:56 +0100 | [diff] [blame] | 88 | tmp = -call->error; |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 89 | ret = put_cmsg(msg, SOL_RXRPC, RXRPC_NET_ERROR, 4, &tmp); |
| 90 | break; |
| 91 | case RXRPC_CALL_LOCAL_ERROR: |
David Howells | 3a92789 | 2017-04-06 10:11:56 +0100 | [diff] [blame] | 92 | tmp = -call->error; |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 93 | ret = put_cmsg(msg, SOL_RXRPC, RXRPC_LOCAL_ERROR, 4, &tmp); |
| 94 | break; |
| 95 | default: |
| 96 | pr_err("Invalid terminal call state %u\n", call->state); |
| 97 | BUG(); |
| 98 | break; |
| 99 | } |
| 100 | |
David Howells | 8499790 | 2016-09-17 11:13:31 +0100 | [diff] [blame] | 101 | trace_rxrpc_recvmsg(call, rxrpc_recvmsg_terminal, call->rx_hard_ack, |
| 102 | call->rx_pkt_offset, call->rx_pkt_len, ret); |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 103 | return ret; |
| 104 | } |
| 105 | |
| 106 | /* |
| 107 | * Pass back notification of a new call. The call is added to the |
| 108 | * to-be-accepted list. This means that the next call to be accepted might not |
| 109 | * be the last call seen awaiting acceptance, but unless we leave this on the |
| 110 | * front of the queue and block all other messages until someone gives us a |
| 111 | * user_ID for it, there's not a lot we can do. |
| 112 | */ |
| 113 | static int rxrpc_recvmsg_new_call(struct rxrpc_sock *rx, |
| 114 | struct rxrpc_call *call, |
| 115 | struct msghdr *msg, int flags) |
| 116 | { |
| 117 | int tmp = 0, ret; |
| 118 | |
| 119 | ret = put_cmsg(msg, SOL_RXRPC, RXRPC_NEW_CALL, 0, &tmp); |
| 120 | |
| 121 | if (ret == 0 && !(flags & MSG_PEEK)) { |
| 122 | _debug("to be accepted"); |
| 123 | write_lock_bh(&rx->recvmsg_lock); |
| 124 | list_del_init(&call->recvmsg_link); |
| 125 | write_unlock_bh(&rx->recvmsg_lock); |
| 126 | |
David Howells | 3432a75 | 2016-09-13 09:05:14 +0100 | [diff] [blame] | 127 | rxrpc_get_call(call, rxrpc_call_got); |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 128 | write_lock(&rx->call_lock); |
| 129 | list_add_tail(&call->accept_link, &rx->to_be_accepted); |
| 130 | write_unlock(&rx->call_lock); |
| 131 | } |
| 132 | |
David Howells | 8499790 | 2016-09-17 11:13:31 +0100 | [diff] [blame] | 133 | trace_rxrpc_recvmsg(call, rxrpc_recvmsg_to_be_accepted, 1, 0, 0, ret); |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 134 | return ret; |
| 135 | } |
| 136 | |
| 137 | /* |
| 138 | * End the packet reception phase. |
| 139 | */ |
David Howells | b69d94d | 2016-09-24 18:05:27 +0100 | [diff] [blame] | 140 | static void rxrpc_end_rx_phase(struct rxrpc_call *call, rxrpc_serial_t serial) |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 141 | { |
| 142 | _enter("%d,%s", call->debug_id, rxrpc_call_states[call->state]); |
| 143 | |
David Howells | 58dc63c | 2016-09-17 10:49:13 +0100 | [diff] [blame] | 144 | trace_rxrpc_receive(call, rxrpc_receive_end, 0, call->rx_top); |
David Howells | 816c9fc | 2016-09-17 10:49:11 +0100 | [diff] [blame] | 145 | ASSERTCMP(call->rx_hard_ack, ==, call->rx_top); |
| 146 | |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 147 | if (call->state == RXRPC_CALL_CLIENT_RECV_REPLY) { |
David Howells | b69d94d | 2016-09-24 18:05:27 +0100 | [diff] [blame] | 148 | rxrpc_propose_ACK(call, RXRPC_ACK_IDLE, 0, serial, true, false, |
David Howells | 9c7ad43 | 2016-09-23 13:50:40 +0100 | [diff] [blame] | 149 | rxrpc_propose_ack_terminal_ack); |
David Howells | a5af7e1 | 2016-10-06 08:11:49 +0100 | [diff] [blame] | 150 | rxrpc_send_ack_packet(call, false); |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 151 | } |
| 152 | |
| 153 | write_lock_bh(&call->state_lock); |
| 154 | |
| 155 | switch (call->state) { |
| 156 | case RXRPC_CALL_CLIENT_RECV_REPLY: |
| 157 | __rxrpc_call_completed(call); |
David Howells | 9749fd2 | 2016-10-06 08:11:50 +0100 | [diff] [blame] | 158 | write_unlock_bh(&call->state_lock); |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 159 | break; |
| 160 | |
| 161 | case RXRPC_CALL_SERVER_RECV_REQUEST: |
David Howells | 71f3ca4 | 2016-09-17 10:49:14 +0100 | [diff] [blame] | 162 | call->tx_phase = true; |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 163 | call->state = RXRPC_CALL_SERVER_ACK_REQUEST; |
David Howells | 9749fd2 | 2016-10-06 08:11:50 +0100 | [diff] [blame] | 164 | call->ack_at = call->expire_at; |
| 165 | write_unlock_bh(&call->state_lock); |
| 166 | rxrpc_propose_ACK(call, RXRPC_ACK_DELAY, 0, serial, false, true, |
| 167 | rxrpc_propose_ack_processing_op); |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 168 | break; |
| 169 | default: |
David Howells | 9749fd2 | 2016-10-06 08:11:50 +0100 | [diff] [blame] | 170 | write_unlock_bh(&call->state_lock); |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 171 | break; |
| 172 | } |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 173 | } |
| 174 | |
| 175 | /* |
| 176 | * Discard a packet we've used up and advance the Rx window by one. |
| 177 | */ |
| 178 | static void rxrpc_rotate_rx_window(struct rxrpc_call *call) |
| 179 | { |
David Howells | 816c9fc | 2016-09-17 10:49:11 +0100 | [diff] [blame] | 180 | struct rxrpc_skb_priv *sp; |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 181 | struct sk_buff *skb; |
David Howells | 58dc63c | 2016-09-17 10:49:13 +0100 | [diff] [blame] | 182 | rxrpc_serial_t serial; |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 183 | rxrpc_seq_t hard_ack, top; |
David Howells | 816c9fc | 2016-09-17 10:49:11 +0100 | [diff] [blame] | 184 | u8 flags; |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 185 | int ix; |
| 186 | |
| 187 | _enter("%d", call->debug_id); |
| 188 | |
| 189 | hard_ack = call->rx_hard_ack; |
| 190 | top = smp_load_acquire(&call->rx_top); |
| 191 | ASSERT(before(hard_ack, top)); |
| 192 | |
| 193 | hard_ack++; |
| 194 | ix = hard_ack & RXRPC_RXTX_BUFF_MASK; |
| 195 | skb = call->rxtx_buffer[ix]; |
David Howells | 71f3ca4 | 2016-09-17 10:49:14 +0100 | [diff] [blame] | 196 | rxrpc_see_skb(skb, rxrpc_skb_rx_rotated); |
David Howells | 816c9fc | 2016-09-17 10:49:11 +0100 | [diff] [blame] | 197 | sp = rxrpc_skb(skb); |
| 198 | flags = sp->hdr.flags; |
David Howells | 58dc63c | 2016-09-17 10:49:13 +0100 | [diff] [blame] | 199 | serial = sp->hdr.serial; |
| 200 | if (call->rxtx_annotations[ix] & RXRPC_RX_ANNO_JUMBO) |
| 201 | serial += (call->rxtx_annotations[ix] & RXRPC_RX_ANNO_JUMBO) - 1; |
| 202 | |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 203 | call->rxtx_buffer[ix] = NULL; |
| 204 | call->rxtx_annotations[ix] = 0; |
| 205 | /* Barrier against rxrpc_input_data(). */ |
| 206 | smp_store_release(&call->rx_hard_ack, hard_ack); |
| 207 | |
David Howells | 71f3ca4 | 2016-09-17 10:49:14 +0100 | [diff] [blame] | 208 | rxrpc_free_skb(skb, rxrpc_skb_rx_freed); |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 209 | |
David Howells | 816c9fc | 2016-09-17 10:49:11 +0100 | [diff] [blame] | 210 | _debug("%u,%u,%02x", hard_ack, top, flags); |
David Howells | 58dc63c | 2016-09-17 10:49:13 +0100 | [diff] [blame] | 211 | trace_rxrpc_receive(call, rxrpc_receive_rotate, serial, hard_ack); |
David Howells | 805b21b | 2016-09-24 18:05:26 +0100 | [diff] [blame] | 212 | if (flags & RXRPC_LAST_PACKET) { |
David Howells | b69d94d | 2016-09-24 18:05:27 +0100 | [diff] [blame] | 213 | rxrpc_end_rx_phase(call, serial); |
David Howells | 805b21b | 2016-09-24 18:05:26 +0100 | [diff] [blame] | 214 | } else { |
| 215 | /* Check to see if there's an ACK that needs sending. */ |
| 216 | if (after_eq(hard_ack, call->ackr_consumed + 2) || |
| 217 | after_eq(top, call->ackr_seen + 2) || |
| 218 | (hard_ack == top && after(hard_ack, call->ackr_consumed))) |
| 219 | rxrpc_propose_ACK(call, RXRPC_ACK_DELAY, 0, serial, |
| 220 | true, false, |
| 221 | rxrpc_propose_ack_rotate_rx); |
| 222 | if (call->ackr_reason) |
David Howells | a5af7e1 | 2016-10-06 08:11:49 +0100 | [diff] [blame] | 223 | rxrpc_send_ack_packet(call, false); |
David Howells | 805b21b | 2016-09-24 18:05:26 +0100 | [diff] [blame] | 224 | } |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 225 | } |
| 226 | |
| 227 | /* |
| 228 | * Decrypt and verify a (sub)packet. The packet's length may be changed due to |
| 229 | * padding, but if this is the case, the packet length will be resident in the |
| 230 | * socket buffer. Note that we can't modify the master skb info as the skb may |
| 231 | * be the home to multiple subpackets. |
| 232 | */ |
| 233 | static int rxrpc_verify_packet(struct rxrpc_call *call, struct sk_buff *skb, |
| 234 | u8 annotation, |
| 235 | unsigned int offset, unsigned int len) |
| 236 | { |
| 237 | struct rxrpc_skb_priv *sp = rxrpc_skb(skb); |
| 238 | rxrpc_seq_t seq = sp->hdr.seq; |
| 239 | u16 cksum = sp->hdr.cksum; |
| 240 | |
| 241 | _enter(""); |
| 242 | |
| 243 | /* For all but the head jumbo subpacket, the security checksum is in a |
| 244 | * jumbo header immediately prior to the data. |
| 245 | */ |
| 246 | if ((annotation & RXRPC_RX_ANNO_JUMBO) > 1) { |
| 247 | __be16 tmp; |
| 248 | if (skb_copy_bits(skb, offset - 2, &tmp, 2) < 0) |
| 249 | BUG(); |
| 250 | cksum = ntohs(tmp); |
| 251 | seq += (annotation & RXRPC_RX_ANNO_JUMBO) - 1; |
| 252 | } |
| 253 | |
| 254 | return call->conn->security->verify_packet(call, skb, offset, len, |
| 255 | seq, cksum); |
| 256 | } |
| 257 | |
| 258 | /* |
| 259 | * Locate the data within a packet. This is complicated by: |
| 260 | * |
| 261 | * (1) An skb may contain a jumbo packet - so we have to find the appropriate |
| 262 | * subpacket. |
| 263 | * |
| 264 | * (2) The (sub)packets may be encrypted and, if so, the encrypted portion |
| 265 | * contains an extra header which includes the true length of the data, |
| 266 | * excluding any encrypted padding. |
| 267 | */ |
| 268 | static int rxrpc_locate_data(struct rxrpc_call *call, struct sk_buff *skb, |
| 269 | u8 *_annotation, |
| 270 | unsigned int *_offset, unsigned int *_len) |
| 271 | { |
David Howells | 775e5b7 | 2016-09-30 13:26:03 +0100 | [diff] [blame] | 272 | unsigned int offset = sizeof(struct rxrpc_wire_header); |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 273 | unsigned int len = *_len; |
| 274 | int ret; |
| 275 | u8 annotation = *_annotation; |
| 276 | |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 277 | /* Locate the subpacket */ |
David Howells | 775e5b7 | 2016-09-30 13:26:03 +0100 | [diff] [blame] | 278 | len = skb->len - offset; |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 279 | if ((annotation & RXRPC_RX_ANNO_JUMBO) > 0) { |
| 280 | offset += (((annotation & RXRPC_RX_ANNO_JUMBO) - 1) * |
| 281 | RXRPC_JUMBO_SUBPKTLEN); |
| 282 | len = (annotation & RXRPC_RX_ANNO_JLAST) ? |
| 283 | skb->len - offset : RXRPC_JUMBO_SUBPKTLEN; |
| 284 | } |
| 285 | |
| 286 | if (!(annotation & RXRPC_RX_ANNO_VERIFIED)) { |
| 287 | ret = rxrpc_verify_packet(call, skb, annotation, offset, len); |
| 288 | if (ret < 0) |
| 289 | return ret; |
| 290 | *_annotation |= RXRPC_RX_ANNO_VERIFIED; |
| 291 | } |
| 292 | |
| 293 | *_offset = offset; |
| 294 | *_len = len; |
| 295 | call->conn->security->locate_data(call, skb, _offset, _len); |
| 296 | return 0; |
| 297 | } |
| 298 | |
| 299 | /* |
| 300 | * Deliver messages to a call. This keeps processing packets until the buffer |
| 301 | * is filled and we find either more DATA (returns 0) or the end of the DATA |
| 302 | * (returns 1). If more packets are required, it returns -EAGAIN. |
| 303 | */ |
| 304 | static int rxrpc_recvmsg_data(struct socket *sock, struct rxrpc_call *call, |
| 305 | struct msghdr *msg, struct iov_iter *iter, |
| 306 | size_t len, int flags, size_t *_offset) |
| 307 | { |
| 308 | struct rxrpc_skb_priv *sp; |
| 309 | struct sk_buff *skb; |
| 310 | rxrpc_seq_t hard_ack, top, seq; |
| 311 | size_t remain; |
| 312 | bool last; |
| 313 | unsigned int rx_pkt_offset, rx_pkt_len; |
David Howells | 816c9fc | 2016-09-17 10:49:11 +0100 | [diff] [blame] | 314 | int ix, copy, ret = -EAGAIN, ret2; |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 315 | |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 316 | rx_pkt_offset = call->rx_pkt_offset; |
| 317 | rx_pkt_len = call->rx_pkt_len; |
| 318 | |
David Howells | 816c9fc | 2016-09-17 10:49:11 +0100 | [diff] [blame] | 319 | if (call->state >= RXRPC_CALL_SERVER_ACK_REQUEST) { |
| 320 | seq = call->rx_hard_ack; |
| 321 | ret = 1; |
| 322 | goto done; |
| 323 | } |
| 324 | |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 325 | /* Barriers against rxrpc_input_data(). */ |
| 326 | hard_ack = call->rx_hard_ack; |
David Howells | d7e1583 | 2017-02-24 21:57:13 +0000 | [diff] [blame] | 327 | seq = hard_ack + 1; |
| 328 | while (top = smp_load_acquire(&call->rx_top), |
| 329 | before_eq(seq, top) |
| 330 | ) { |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 331 | ix = seq & RXRPC_RXTX_BUFF_MASK; |
| 332 | skb = call->rxtx_buffer[ix]; |
David Howells | 8499790 | 2016-09-17 11:13:31 +0100 | [diff] [blame] | 333 | if (!skb) { |
| 334 | trace_rxrpc_recvmsg(call, rxrpc_recvmsg_hole, seq, |
| 335 | rx_pkt_offset, rx_pkt_len, 0); |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 336 | break; |
David Howells | 8499790 | 2016-09-17 11:13:31 +0100 | [diff] [blame] | 337 | } |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 338 | smp_rmb(); |
David Howells | 71f3ca4 | 2016-09-17 10:49:14 +0100 | [diff] [blame] | 339 | rxrpc_see_skb(skb, rxrpc_skb_rx_seen); |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 340 | sp = rxrpc_skb(skb); |
| 341 | |
David Howells | 58dc63c | 2016-09-17 10:49:13 +0100 | [diff] [blame] | 342 | if (!(flags & MSG_PEEK)) |
| 343 | trace_rxrpc_receive(call, rxrpc_receive_front, |
| 344 | sp->hdr.serial, seq); |
| 345 | |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 346 | if (msg) |
| 347 | sock_recv_timestamp(msg, sock->sk, skb); |
| 348 | |
David Howells | 2e2ea51 | 2016-09-17 10:49:11 +0100 | [diff] [blame] | 349 | if (rx_pkt_offset == 0) { |
David Howells | 816c9fc | 2016-09-17 10:49:11 +0100 | [diff] [blame] | 350 | ret2 = rxrpc_locate_data(call, skb, |
| 351 | &call->rxtx_annotations[ix], |
| 352 | &rx_pkt_offset, &rx_pkt_len); |
David Howells | 8499790 | 2016-09-17 11:13:31 +0100 | [diff] [blame] | 353 | trace_rxrpc_recvmsg(call, rxrpc_recvmsg_next, seq, |
| 354 | rx_pkt_offset, rx_pkt_len, ret2); |
David Howells | 816c9fc | 2016-09-17 10:49:11 +0100 | [diff] [blame] | 355 | if (ret2 < 0) { |
| 356 | ret = ret2; |
David Howells | 2e2ea51 | 2016-09-17 10:49:11 +0100 | [diff] [blame] | 357 | goto out; |
David Howells | 816c9fc | 2016-09-17 10:49:11 +0100 | [diff] [blame] | 358 | } |
David Howells | 8499790 | 2016-09-17 11:13:31 +0100 | [diff] [blame] | 359 | } else { |
| 360 | trace_rxrpc_recvmsg(call, rxrpc_recvmsg_cont, seq, |
| 361 | rx_pkt_offset, rx_pkt_len, 0); |
David Howells | 2e2ea51 | 2016-09-17 10:49:11 +0100 | [diff] [blame] | 362 | } |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 363 | |
| 364 | /* We have to handle short, empty and used-up DATA packets. */ |
| 365 | remain = len - *_offset; |
| 366 | copy = rx_pkt_len; |
| 367 | if (copy > remain) |
| 368 | copy = remain; |
| 369 | if (copy > 0) { |
David Howells | 816c9fc | 2016-09-17 10:49:11 +0100 | [diff] [blame] | 370 | ret2 = skb_copy_datagram_iter(skb, rx_pkt_offset, iter, |
| 371 | copy); |
| 372 | if (ret2 < 0) { |
| 373 | ret = ret2; |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 374 | goto out; |
David Howells | 816c9fc | 2016-09-17 10:49:11 +0100 | [diff] [blame] | 375 | } |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 376 | |
| 377 | /* handle piecemeal consumption of data packets */ |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 378 | rx_pkt_offset += copy; |
| 379 | rx_pkt_len -= copy; |
| 380 | *_offset += copy; |
| 381 | } |
| 382 | |
| 383 | if (rx_pkt_len > 0) { |
David Howells | 8499790 | 2016-09-17 11:13:31 +0100 | [diff] [blame] | 384 | trace_rxrpc_recvmsg(call, rxrpc_recvmsg_full, seq, |
| 385 | rx_pkt_offset, rx_pkt_len, 0); |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 386 | ASSERTCMP(*_offset, ==, len); |
David Howells | 816c9fc | 2016-09-17 10:49:11 +0100 | [diff] [blame] | 387 | ret = 0; |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 388 | break; |
| 389 | } |
| 390 | |
| 391 | /* The whole packet has been transferred. */ |
| 392 | last = sp->hdr.flags & RXRPC_LAST_PACKET; |
| 393 | if (!(flags & MSG_PEEK)) |
| 394 | rxrpc_rotate_rx_window(call); |
| 395 | rx_pkt_offset = 0; |
| 396 | rx_pkt_len = 0; |
| 397 | |
David Howells | 816c9fc | 2016-09-17 10:49:11 +0100 | [diff] [blame] | 398 | if (last) { |
| 399 | ASSERTCMP(seq, ==, READ_ONCE(call->rx_top)); |
| 400 | ret = 1; |
| 401 | goto out; |
| 402 | } |
David Howells | d7e1583 | 2017-02-24 21:57:13 +0000 | [diff] [blame] | 403 | |
| 404 | seq++; |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 405 | } |
| 406 | |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 407 | out: |
| 408 | if (!(flags & MSG_PEEK)) { |
| 409 | call->rx_pkt_offset = rx_pkt_offset; |
| 410 | call->rx_pkt_len = rx_pkt_len; |
| 411 | } |
David Howells | 816c9fc | 2016-09-17 10:49:11 +0100 | [diff] [blame] | 412 | done: |
David Howells | 8499790 | 2016-09-17 11:13:31 +0100 | [diff] [blame] | 413 | trace_rxrpc_recvmsg(call, rxrpc_recvmsg_data_return, seq, |
| 414 | rx_pkt_offset, rx_pkt_len, ret); |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 415 | return ret; |
| 416 | } |
| 417 | |
| 418 | /* |
| 419 | * Receive a message from an RxRPC socket |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 420 | * - we need to be careful about two or more threads calling recvmsg |
| 421 | * simultaneously |
| 422 | */ |
Ying Xue | 1b78414 | 2015-03-02 15:37:48 +0800 | [diff] [blame] | 423 | int rxrpc_recvmsg(struct socket *sock, struct msghdr *msg, size_t len, |
| 424 | int flags) |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 425 | { |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 426 | struct rxrpc_call *call; |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 427 | struct rxrpc_sock *rx = rxrpc_sk(sock->sk); |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 428 | struct list_head *l; |
| 429 | size_t copied = 0; |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 430 | long timeo; |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 431 | int ret; |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 432 | |
| 433 | DEFINE_WAIT(wait); |
| 434 | |
David Howells | 8499790 | 2016-09-17 11:13:31 +0100 | [diff] [blame] | 435 | trace_rxrpc_recvmsg(NULL, rxrpc_recvmsg_enter, 0, 0, 0, 0); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 436 | |
| 437 | if (flags & (MSG_OOB | MSG_TRUNC)) |
| 438 | return -EOPNOTSUPP; |
| 439 | |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 440 | timeo = sock_rcvtimeo(&rx->sk, flags & MSG_DONTWAIT); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 441 | |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 442 | try_again: |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 443 | lock_sock(&rx->sk); |
| 444 | |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 445 | /* Return immediately if a client socket has no outstanding calls */ |
| 446 | if (RB_EMPTY_ROOT(&rx->calls) && |
| 447 | list_empty(&rx->recvmsg_q) && |
| 448 | rx->sk.sk_state != RXRPC_SERVER_LISTENING) { |
| 449 | release_sock(&rx->sk); |
| 450 | return -ENODATA; |
| 451 | } |
| 452 | |
| 453 | if (list_empty(&rx->recvmsg_q)) { |
| 454 | ret = -EWOULDBLOCK; |
David Howells | 8499790 | 2016-09-17 11:13:31 +0100 | [diff] [blame] | 455 | if (timeo == 0) { |
| 456 | call = NULL; |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 457 | goto error_no_call; |
David Howells | 8499790 | 2016-09-17 11:13:31 +0100 | [diff] [blame] | 458 | } |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 459 | |
| 460 | release_sock(&rx->sk); |
| 461 | |
| 462 | /* Wait for something to happen */ |
| 463 | prepare_to_wait_exclusive(sk_sleep(&rx->sk), &wait, |
| 464 | TASK_INTERRUPTIBLE); |
| 465 | ret = sock_error(&rx->sk); |
| 466 | if (ret) |
| 467 | goto wait_error; |
| 468 | |
| 469 | if (list_empty(&rx->recvmsg_q)) { |
| 470 | if (signal_pending(current)) |
| 471 | goto wait_interrupted; |
David Howells | 8499790 | 2016-09-17 11:13:31 +0100 | [diff] [blame] | 472 | trace_rxrpc_recvmsg(NULL, rxrpc_recvmsg_wait, |
| 473 | 0, 0, 0, 0); |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 474 | timeo = schedule_timeout(timeo); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 475 | } |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 476 | finish_wait(sk_sleep(&rx->sk), &wait); |
| 477 | goto try_again; |
| 478 | } |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 479 | |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 480 | /* Find the next call and dequeue it if we're not just peeking. If we |
| 481 | * do dequeue it, that comes with a ref that we will need to release. |
| 482 | */ |
| 483 | write_lock_bh(&rx->recvmsg_lock); |
| 484 | l = rx->recvmsg_q.next; |
| 485 | call = list_entry(l, struct rxrpc_call, recvmsg_link); |
| 486 | if (!(flags & MSG_PEEK)) |
| 487 | list_del_init(&call->recvmsg_link); |
| 488 | else |
David Howells | fff72429 | 2016-09-07 14:34:21 +0100 | [diff] [blame] | 489 | rxrpc_get_call(call, rxrpc_call_got); |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 490 | write_unlock_bh(&rx->recvmsg_lock); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 491 | |
David Howells | 8499790 | 2016-09-17 11:13:31 +0100 | [diff] [blame] | 492 | trace_rxrpc_recvmsg(call, rxrpc_recvmsg_dequeue, 0, 0, 0, 0); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 493 | |
David Howells | 540b1c4 | 2017-02-27 15:43:06 +0000 | [diff] [blame] | 494 | /* We're going to drop the socket lock, so we need to lock the call |
| 495 | * against interference by sendmsg. |
| 496 | */ |
| 497 | if (!mutex_trylock(&call->user_mutex)) { |
| 498 | ret = -EWOULDBLOCK; |
| 499 | if (flags & MSG_DONTWAIT) |
| 500 | goto error_requeue_call; |
| 501 | ret = -ERESTARTSYS; |
| 502 | if (mutex_lock_interruptible(&call->user_mutex) < 0) |
| 503 | goto error_requeue_call; |
| 504 | } |
| 505 | |
| 506 | release_sock(&rx->sk); |
| 507 | |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 508 | if (test_bit(RXRPC_CALL_RELEASED, &call->flags)) |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 509 | BUG(); |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 510 | |
| 511 | if (test_bit(RXRPC_CALL_HAS_USERID, &call->flags)) { |
| 512 | if (flags & MSG_CMSG_COMPAT) { |
| 513 | unsigned int id32 = call->user_call_ID; |
| 514 | |
| 515 | ret = put_cmsg(msg, SOL_RXRPC, RXRPC_USER_CALL_ID, |
| 516 | sizeof(unsigned int), &id32); |
| 517 | } else { |
| 518 | ret = put_cmsg(msg, SOL_RXRPC, RXRPC_USER_CALL_ID, |
| 519 | sizeof(unsigned long), |
| 520 | &call->user_call_ID); |
David Howells | f5c17aa | 2016-08-30 09:49:28 +0100 | [diff] [blame] | 521 | } |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 522 | if (ret < 0) |
David Howells | 540b1c4 | 2017-02-27 15:43:06 +0000 | [diff] [blame] | 523 | goto error_unlock_call; |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 524 | } |
| 525 | |
| 526 | if (msg->msg_name) { |
David Howells | 68d6d1a | 2017-06-05 14:30:49 +0100 | [diff] [blame] | 527 | struct sockaddr_rxrpc *srx = msg->msg_name; |
| 528 | size_t len = sizeof(call->peer->srx); |
| 529 | |
| 530 | memcpy(msg->msg_name, &call->peer->srx, len); |
| 531 | srx->srx_service = call->service_id; |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 532 | msg->msg_namelen = len; |
| 533 | } |
| 534 | |
David Howells | 146d8fe | 2017-03-04 00:01:41 +0000 | [diff] [blame] | 535 | switch (READ_ONCE(call->state)) { |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 536 | case RXRPC_CALL_SERVER_ACCEPTING: |
| 537 | ret = rxrpc_recvmsg_new_call(rx, call, msg, flags); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 538 | break; |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 539 | case RXRPC_CALL_CLIENT_RECV_REPLY: |
| 540 | case RXRPC_CALL_SERVER_RECV_REQUEST: |
| 541 | case RXRPC_CALL_SERVER_ACK_REQUEST: |
| 542 | ret = rxrpc_recvmsg_data(sock, call, msg, &msg->msg_iter, len, |
| 543 | flags, &copied); |
| 544 | if (ret == -EAGAIN) |
| 545 | ret = 0; |
David Howells | 33b603f | 2016-09-13 22:36:21 +0100 | [diff] [blame] | 546 | |
| 547 | if (after(call->rx_top, call->rx_hard_ack) && |
| 548 | call->rxtx_buffer[(call->rx_hard_ack + 1) & RXRPC_RXTX_BUFF_MASK]) |
| 549 | rxrpc_notify_socket(call); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 550 | break; |
| 551 | default: |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 552 | ret = 0; |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 553 | break; |
| 554 | } |
| 555 | |
| 556 | if (ret < 0) |
David Howells | 540b1c4 | 2017-02-27 15:43:06 +0000 | [diff] [blame] | 557 | goto error_unlock_call; |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 558 | |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 559 | if (call->state == RXRPC_CALL_COMPLETE) { |
| 560 | ret = rxrpc_recvmsg_term(call, msg); |
| 561 | if (ret < 0) |
David Howells | 540b1c4 | 2017-02-27 15:43:06 +0000 | [diff] [blame] | 562 | goto error_unlock_call; |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 563 | if (!(flags & MSG_PEEK)) |
| 564 | rxrpc_release_call(rx, call); |
| 565 | msg->msg_flags |= MSG_EOR; |
| 566 | ret = 1; |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 567 | } |
| 568 | |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 569 | if (ret == 0) |
| 570 | msg->msg_flags |= MSG_MORE; |
| 571 | else |
| 572 | msg->msg_flags &= ~MSG_MORE; |
| 573 | ret = copied; |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 574 | |
David Howells | 540b1c4 | 2017-02-27 15:43:06 +0000 | [diff] [blame] | 575 | error_unlock_call: |
| 576 | mutex_unlock(&call->user_mutex); |
David Howells | fff72429 | 2016-09-07 14:34:21 +0100 | [diff] [blame] | 577 | rxrpc_put_call(call, rxrpc_call_put); |
David Howells | 540b1c4 | 2017-02-27 15:43:06 +0000 | [diff] [blame] | 578 | trace_rxrpc_recvmsg(call, rxrpc_recvmsg_return, 0, 0, 0, ret); |
| 579 | return ret; |
| 580 | |
| 581 | error_requeue_call: |
| 582 | if (!(flags & MSG_PEEK)) { |
| 583 | write_lock_bh(&rx->recvmsg_lock); |
| 584 | list_add(&call->recvmsg_link, &rx->recvmsg_q); |
| 585 | write_unlock_bh(&rx->recvmsg_lock); |
| 586 | trace_rxrpc_recvmsg(call, rxrpc_recvmsg_requeue, 0, 0, 0, 0); |
| 587 | } else { |
| 588 | rxrpc_put_call(call, rxrpc_call_put); |
| 589 | } |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 590 | error_no_call: |
| 591 | release_sock(&rx->sk); |
David Howells | 8499790 | 2016-09-17 11:13:31 +0100 | [diff] [blame] | 592 | trace_rxrpc_recvmsg(call, rxrpc_recvmsg_return, 0, 0, 0, ret); |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 593 | return ret; |
| 594 | |
David Howells | 17926a7 | 2007-04-26 15:48:28 -0700 | [diff] [blame] | 595 | wait_interrupted: |
| 596 | ret = sock_intr_errno(timeo); |
| 597 | wait_error: |
Eric Dumazet | 4a4771a | 2010-04-25 22:20:06 +0000 | [diff] [blame] | 598 | finish_wait(sk_sleep(&rx->sk), &wait); |
David Howells | 8499790 | 2016-09-17 11:13:31 +0100 | [diff] [blame] | 599 | call = NULL; |
| 600 | goto error_no_call; |
David Howells | d001648 | 2016-08-30 20:42:14 +0100 | [diff] [blame] | 601 | } |
David Howells | 651350d | 2007-04-26 15:50:17 -0700 | [diff] [blame] | 602 | |
| 603 | /** |
David Howells | d001648 | 2016-08-30 20:42:14 +0100 | [diff] [blame] | 604 | * rxrpc_kernel_recv_data - Allow a kernel service to receive data/info |
| 605 | * @sock: The socket that the call exists on |
| 606 | * @call: The call to send data through |
| 607 | * @buf: The buffer to receive into |
| 608 | * @size: The size of the buffer, including data already read |
| 609 | * @_offset: The running offset into the buffer. |
| 610 | * @want_more: True if more data is expected to be read |
| 611 | * @_abort: Where the abort code is stored if -ECONNABORTED is returned |
David Howells | a68f4a2 | 2017-10-18 11:36:39 +0100 | [diff] [blame] | 612 | * @_service: Where to store the actual service ID (may be upgraded) |
David Howells | 651350d | 2007-04-26 15:50:17 -0700 | [diff] [blame] | 613 | * |
David Howells | d001648 | 2016-08-30 20:42:14 +0100 | [diff] [blame] | 614 | * Allow a kernel service to receive data and pick up information about the |
| 615 | * state of a call. Returns 0 if got what was asked for and there's more |
| 616 | * available, 1 if we got what was asked for and we're at the end of the data |
| 617 | * and -EAGAIN if we need more data. |
| 618 | * |
| 619 | * Note that we may return -EAGAIN to drain empty packets at the end of the |
| 620 | * data, even if we've already copied over the requested data. |
| 621 | * |
| 622 | * This function adds the amount it transfers to *_offset, so this should be |
| 623 | * precleared as appropriate. Note that the amount remaining in the buffer is |
| 624 | * taken to be size - *_offset. |
| 625 | * |
| 626 | * *_abort should also be initialised to 0. |
David Howells | 651350d | 2007-04-26 15:50:17 -0700 | [diff] [blame] | 627 | */ |
David Howells | d001648 | 2016-08-30 20:42:14 +0100 | [diff] [blame] | 628 | int rxrpc_kernel_recv_data(struct socket *sock, struct rxrpc_call *call, |
| 629 | void *buf, size_t size, size_t *_offset, |
David Howells | a68f4a2 | 2017-10-18 11:36:39 +0100 | [diff] [blame] | 630 | bool want_more, u32 *_abort, u16 *_service) |
David Howells | 651350d | 2007-04-26 15:50:17 -0700 | [diff] [blame] | 631 | { |
David Howells | d001648 | 2016-08-30 20:42:14 +0100 | [diff] [blame] | 632 | struct iov_iter iter; |
| 633 | struct kvec iov; |
| 634 | int ret; |
David Howells | 651350d | 2007-04-26 15:50:17 -0700 | [diff] [blame] | 635 | |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 636 | _enter("{%d,%s},%zu/%zu,%d", |
| 637 | call->debug_id, rxrpc_call_states[call->state], |
| 638 | *_offset, size, want_more); |
David Howells | d001648 | 2016-08-30 20:42:14 +0100 | [diff] [blame] | 639 | |
| 640 | ASSERTCMP(*_offset, <=, size); |
| 641 | ASSERTCMP(call->state, !=, RXRPC_CALL_SERVER_ACCEPTING); |
| 642 | |
| 643 | iov.iov_base = buf + *_offset; |
| 644 | iov.iov_len = size - *_offset; |
| 645 | iov_iter_kvec(&iter, ITER_KVEC | READ, &iov, 1, size - *_offset); |
| 646 | |
David Howells | 540b1c4 | 2017-02-27 15:43:06 +0000 | [diff] [blame] | 647 | mutex_lock(&call->user_mutex); |
David Howells | d001648 | 2016-08-30 20:42:14 +0100 | [diff] [blame] | 648 | |
David Howells | 146d8fe | 2017-03-04 00:01:41 +0000 | [diff] [blame] | 649 | switch (READ_ONCE(call->state)) { |
David Howells | d001648 | 2016-08-30 20:42:14 +0100 | [diff] [blame] | 650 | case RXRPC_CALL_CLIENT_RECV_REPLY: |
| 651 | case RXRPC_CALL_SERVER_RECV_REQUEST: |
| 652 | case RXRPC_CALL_SERVER_ACK_REQUEST: |
David Howells | 248f219 | 2016-09-08 11:10:12 +0100 | [diff] [blame] | 653 | ret = rxrpc_recvmsg_data(sock, call, NULL, &iter, size, 0, |
| 654 | _offset); |
David Howells | d001648 | 2016-08-30 20:42:14 +0100 | [diff] [blame] | 655 | if (ret < 0) |
| 656 | goto out; |
| 657 | |
| 658 | /* We can only reach here with a partially full buffer if we |
| 659 | * have reached the end of the data. We must otherwise have a |
| 660 | * full buffer or have been given -EAGAIN. |
| 661 | */ |
| 662 | if (ret == 1) { |
| 663 | if (*_offset < size) |
| 664 | goto short_data; |
| 665 | if (!want_more) |
| 666 | goto read_phase_complete; |
| 667 | ret = 0; |
| 668 | goto out; |
| 669 | } |
| 670 | |
| 671 | if (!want_more) |
| 672 | goto excess_data; |
| 673 | goto out; |
| 674 | |
| 675 | case RXRPC_CALL_COMPLETE: |
| 676 | goto call_complete; |
| 677 | |
| 678 | default: |
David Howells | d001648 | 2016-08-30 20:42:14 +0100 | [diff] [blame] | 679 | ret = -EINPROGRESS; |
| 680 | goto out; |
| 681 | } |
| 682 | |
| 683 | read_phase_complete: |
| 684 | ret = 1; |
| 685 | out: |
David Howells | a68f4a2 | 2017-10-18 11:36:39 +0100 | [diff] [blame] | 686 | if (_service) |
| 687 | *_service = call->service_id; |
David Howells | 540b1c4 | 2017-02-27 15:43:06 +0000 | [diff] [blame] | 688 | mutex_unlock(&call->user_mutex); |
David Howells | d001648 | 2016-08-30 20:42:14 +0100 | [diff] [blame] | 689 | _leave(" = %d [%zu,%d]", ret, *_offset, *_abort); |
| 690 | return ret; |
| 691 | |
| 692 | short_data: |
David Howells | fb46f6e | 2017-04-06 10:12:00 +0100 | [diff] [blame] | 693 | trace_rxrpc_rx_eproto(call, 0, tracepoint_string("short_data")); |
David Howells | d001648 | 2016-08-30 20:42:14 +0100 | [diff] [blame] | 694 | ret = -EBADMSG; |
| 695 | goto out; |
| 696 | excess_data: |
David Howells | fb46f6e | 2017-04-06 10:12:00 +0100 | [diff] [blame] | 697 | trace_rxrpc_rx_eproto(call, 0, tracepoint_string("excess_data")); |
David Howells | d001648 | 2016-08-30 20:42:14 +0100 | [diff] [blame] | 698 | ret = -EMSGSIZE; |
| 699 | goto out; |
| 700 | call_complete: |
| 701 | *_abort = call->abort_code; |
David Howells | 3a92789 | 2017-04-06 10:11:56 +0100 | [diff] [blame] | 702 | ret = call->error; |
David Howells | d001648 | 2016-08-30 20:42:14 +0100 | [diff] [blame] | 703 | if (call->completion == RXRPC_CALL_SUCCEEDED) { |
| 704 | ret = 1; |
| 705 | if (size > 0) |
| 706 | ret = -ECONNRESET; |
| 707 | } |
| 708 | goto out; |
David Howells | 651350d | 2007-04-26 15:50:17 -0700 | [diff] [blame] | 709 | } |
David Howells | d001648 | 2016-08-30 20:42:14 +0100 | [diff] [blame] | 710 | EXPORT_SYMBOL(rxrpc_kernel_recv_data); |