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dev_nic.c @ 690

Last change on this file since 690 was 683, checked in by alain, 3 years ago
All modifications required to support the <tcp_chat> application including error recovery in case of packet loss.A
File size: 124.5 KB

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1	/*
2	* dev_nic.c - NIC (Network Controler) generic device API implementation.
3	*
4	* Author Alain Greiner (2016,2017,2018,2019,2020)
5	*
6	* Copyright (c) UPMC Sorbonne Universites
7	*
8	* This file is part of ALMOS-MKH.
9	*
10	* ALMOS-MKH is free software; you can redistribute it and/or modify it
11	* under the terms of the GNU General Public License as published by
12	* the Free Software Foundation; version 2.0 of the License.
13	*
14	* ALMOS-MKH is distributed in the hope that it will be useful, but
15	* WITHOUT ANY WARRANTY; without even the implied warranty of
16	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17	* General Public License for more details.
18	*
19	* You should have received a copy of the GNU General Public License
20	* along with ALMOS-MKH; if not, write to the Free Software Foundation,
21	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
22	*/
23
24	#include <hal_kernel_types.h>
25	#include <hal_special.h>
26	#include <hal_uspace.h>
27	#include <remote_buf.h>
28	#include <memcpy.h>
29	#include <printk.h>
30	#include <chdev.h>
31	#include <thread.h>
32	#include <ksocket.h>
33	#include <hal_drivers.h>
34	#include <dev_nic.h>
35	#include <vfs.h>
36	#include <shared_socket.h>
37
38	/////////////////////////////////////////////////////////////////////////////////////////
39	// Extern global variables
40	/////////////////////////////////////////////////////////////////////////////////////////
41
42	extern chdev_directory_t chdev_dir; // allocated in kernel_init.c
43
44	////////////////////////////////////
45	void dev_nic_init( chdev_t * chdev )
46	{
47
48	assert( __FUNCTION__ , (chdev->func == DEV_FUNC_NIC) ,
49	"bad func value");
50
51	thread_t * new_thread;
52	error_t error;
53
54	// get "channel" & "is_rx" fields from chdev descriptor
55	uint32_t channel = chdev->channel;
56	bool_t is_rx = chdev->is_rx;
57
58	// set chdev name
59	if( is_rx ) snprintk( chdev->name , 16 , "nic%d_rx" , channel );
60	else snprintk( chdev->name , 16 , "nic%d_tx" , channel );
61
62	// initialize the root of the listening sockets list
63	xlist_root_init( XPTR( local_cxy , &chdev->ext.nic.root ) );
64
65	// initialize the lock protecting this list
66	remote_busylock_init( XPTR( local_cxy , &chdev->ext.nic.lock ),
67	LOCK_LISTEN_SOCKET );
68
69	// call driver init function for this chdev
70	hal_drivers_nic_init( chdev );
71
72	// select a core to execute the NIC server thread
73	lid_t lid = cluster_select_local_core( local_cxy );
74
75	// bind the NIC IRQ to the selected core
76	dev_pic_bind_irq( lid , chdev );
77
78	// build pointer on server function
79	void * server_func = is_rx ? &dev_nic_rx_server : &dev_nic_tx_server;
80
81	// create server thread
82	error = thread_kernel_create( &new_thread,
83	THREAD_DEV,
84	server_func,
85	chdev,
86	lid );
87	if( error )
88	{
89	printk("\n[PANIC] in %s : cannot create server thread\n", __FUNCTION__ );
90	return;
91	}
92
93	// set "server" field in chdev descriptor
94	chdev->server = new_thread;
95
96	// set "chdev" field in thread descriptor
97	new_thread->chdev = chdev;
98
99	// unblock server thread
100	thread_unblock( XPTR( local_cxy , new_thread ) , THREAD_BLOCKED_GLOBAL );
101
102	#if (DEBUG_DEV_NIC_TX \|\| DEBUG_DEV_NIC_RX)
103	thread_t * this = CURRENT_THREAD;
104	if( is_rx )
105	printk("\n[%s] thread[%x,%x] initialized NIC_RX[%d] / server %x\n",
106	__FUNCTION__, this->process->pid, this->trdid, channel, new_thread->trdid );
107	else
108	printk("\n[%s] thread[%x,%x] initialized NIC_TX[%d] / server %x\n",
109	__FUNCTION__, this->process->pid, this->trdid, channel, new_thread->trdid );
110	#endif
111
112	} // end dev_nic_init()
113
114
115	///////////////////////////////////////////////////////////////////////////////////////////
116	// Functions directly called by the client threads
117	///////////////////////////////////////////////////////////////////////////////////////////
118
119	////////////////////////////////////////
120	uint32_t dev_nic_get_key( uint32_t addr,
121	uint16_t port )
122	{
123	thread_t * this = CURRENT_THREAD;
124
125	// get cluster and local pointer fo the nic_tx[0] chdev
126	xptr_t dev_xp = chdev_dir.nic_tx[0];
127	chdev_t * dev_ptr = GET_PTR( dev_xp );
128	cxy_t dev_cxy = GET_CXY( dev_xp );
129
130	if( dev_xp == XPTR_NULL )
131	{
132
133	#if DEBUG_DEV_NIC_ERROR
134	printk("\n[ERROR] in %s : nic_tx[0] chdev undefined in chdev_dir of cluster %x\n",
135	__FUNCTION__, local_cxy );
136	#endif
137	return -1;
138	}
139
140	// set command arguments in client thread descriptor
141	this->nic_cmd.buffer = (uint8_t *)addr;
142	this->nic_cmd.length = (uint32_t)port;
143	this->nic_cmd.dev_xp = dev_xp;
144	this->nic_cmd.type = NIC_CMD_GET_KEY;
145
146	// get cmd function pointer from nic_tx[0] chdev descriptor
147	dev_cmd_t * cmd = hal_remote_lpt( XPTR( dev_cxy , &dev_ptr->cmd ));
148
149	// call driver
150	cmd( XPTR( local_cxy , this ) );
151
152	// return command status
153	return this->nic_cmd.status;
154
155	} // end dev_nic_get_key()
156
157	//////////////////////////////////////////
158	error_t dev_nic_set_run( uint32_t channel,
159	uint32_t run )
160	{
161	thread_t * this = CURRENT_THREAD;
162
163	if( channel >= LOCAL_CLUSTER->nb_nic_channels ) return -1;
164
165	// get cluster and local pointer fo the nic_tx[channel] chdev
166	xptr_t dev_xp = chdev_dir.nic_tx[channel];
167	chdev_t * dev_ptr = GET_PTR( dev_xp );
168	cxy_t dev_cxy = GET_CXY( dev_xp );
169
170	if( dev_xp == XPTR_NULL )
171	{
172
173	#if DEBUG_DEV_NIC_ERROR
174	printk("\n[ERROR] in %s : nic_tx[%d] chdev undefined in chdev_dir of cluster %x\n",
175	__FUNCTION__, channel, local_cxy );
176	#endif
177	return -1;
178	}
179
180	// set command arguments in client thread descriptor
181	this->nic_cmd.dev_xp = dev_xp;
182	this->nic_cmd.type = NIC_CMD_SET_RUN;
183	this->nic_cmd.length = channel;
184	this->nic_cmd.status = run;
185
186	// get cmd function pointer from nic_tx[channel] chdev descriptor
187	dev_cmd_t * cmd = hal_remote_lpt( XPTR( dev_cxy , &dev_ptr->cmd ));
188
189	// call driver
190	cmd( XPTR( local_cxy , this ) );
191
192	// return "error"
193	return this->nic_cmd.error;
194
195	} // end dev_nic_set_run()
196
197	//////////////////////////////////
198	error_t dev_nic_get_instru( void )
199	{
200	thread_t * this = CURRENT_THREAD;
201
202	// get cluster and local pointer fo the nic_tx[0] chdev
203	xptr_t dev_xp = chdev_dir.nic_tx[0];
204	chdev_t * dev_ptr = GET_PTR( dev_xp );
205	cxy_t dev_cxy = GET_CXY( dev_xp );
206
207	if( dev_xp == XPTR_NULL )
208	{
209
210	#if DEBUG_DEV_NIC_ERROR
211	printk("\n[ERROR] in %s : nic_tx[0] chdev undefined in chdev_dir of cluster %x\n",
212	__FUNCTION__, local_cxy );
213	#endif
214	return -1;
215	}
216
217	// set command arguments in client thread descriptor
218	this->nic_cmd.dev_xp = dev_xp;
219	this->nic_cmd.type = NIC_CMD_GET_INSTRU;
220
221	// get cmd function pointer from nic_tx[0] chdev descriptor
222	dev_cmd_t * cmd = hal_remote_lpt( XPTR( dev_cxy , &dev_ptr->cmd ));
223
224	// call driver
225	cmd( XPTR( local_cxy , this ) );
226
227	// return "error"
228	return this->nic_cmd.error;
229
230	} // end dev_nic_get_instru()
231
232
233	////////////////////////////////////
234	error_t dev_nic_clear_instru( void )
235	{
236	thread_t * this = CURRENT_THREAD;
237
238	// get cluster and local pointer fo the nic_tx[0] chdev
239	xptr_t dev_xp = chdev_dir.nic_tx[0];
240	chdev_t * dev_ptr = GET_PTR( dev_xp );
241	cxy_t dev_cxy = GET_CXY( dev_xp );
242
243	if( dev_xp == XPTR_NULL )
244	{
245
246	#if DEBUG_DEV_NIC_ERROR
247	printk("\n[ERROR] in %s : nic_tx[0] chdev undefined in chdev_dir of cluster %x\n",
248	__FUNCTION__, local_cxy );
249	#endif
250	return -1;
251	}
252
253	// set command arguments in client thread descriptor
254	this->nic_cmd.dev_xp = dev_xp;
255	this->nic_cmd.type = NIC_CMD_GET_INSTRU;
256
257	// get cmd function pointer from nic_tx[0] chdev descriptor
258	dev_cmd_t * cmd = hal_remote_lpt( XPTR( dev_cxy , &dev_ptr->cmd ));
259
260	// call driver
261	cmd( XPTR( local_cxy , this ) );
262
263	// return "error"
264	return this->nic_cmd.error;
265
266	} // end dev_nic_clear_instru()
267
268
269	////////////////////////////////////////////////////////////////////////////////////////////
270	// Static functions called by the NIC_RX server & NIC_TX server threads
271	////////////////////////////////////////////////////////////////////////////////////////////
272
273	////////////////////////////////////////////////////////////////////////////////////////////
274	// This static function is used by the dev_nic_rx_handle_tcp() function
275	// to check acceptability of a given sequence number. It returns true when
276	// the <seq> argument is contained in a wrap-around window defined by the
277	// <min> and <max> arguments. The window wrap-around when (min > max).
278	////////////////////////////////////////////////////////////////////////////////////////////
279	// @ seq : [in] value to be checked.
280	// @ min : [in] first base.
281	// @ max : [in] window size.
282	////////////////////////////////////////////////////////////////////////////////////////////
283	static inline bool_t is_in_window( uint32_t seq,
284	uint32_t min,
285	uint32_t max )
286	{
287	if( max >= min ) // no wrap_around => only one window [min,max]
288	{
289	return( (seq >= min) && (seq <= max) );
290	}
291	else // window wrap-around => two windows [min,0xFFFFFFFF] and [0,max]
292	{
293	return( (seq <= max) \|\| (seq >= min) );
294	}
295	}
296
297	////////////////////////////////////////////////////////////////////////////////////////
298	// This static function computes the checksum for an IP packet header.
299	// The "checksum" field itself is not taken into account for this computation.
300	////////////////////////////////////////////////////////////////////////////////////////
301	// @ buffer : [in] pointer on IP packet header (20 bytes)
302	// @ return the checksum value on 16 bits
303	////////////////////////////////////////////////////////////////////////////////////////
304	static uint16_t dev_nic_ip_checksum( uint8_t * buffer )
305	{
306	uint32_t i;
307	uint32_t cs; // 32 bits accumulator
308	uint16_t * buf;
309
310	buf = (uint16_t *)buffer;
311
312	// compute checksum
313	for( i = 0 , cs = 0 ; i < 10 ; i++ )
314	{
315	if( i != 5 ) cs += buf[i];
316	}
317
318	// one's complement
319	return ~cs;
320	}
321
322	////////////////////////////////////////////////////////////////////////////////////////
323	// This static function computes the checksum for a TCP segment or an UDP packet,
324	// defined by the <buffer> and <length> arguments.
325	// It includes the "pseudo header "defined by the <src_ip_addr>, <dst_ip_addr>, and
326	// <tcp_length> arguments, and by the UDP/TCP protocol code.
327	////////////////////////////////////////////////////////////////////////////////////////
328	// @ buffer : [in] pointer on buffer containing the TCP segment or UDP packet.
329	// @ length : [in] number of bytes in this packet/segment (including header).
330	// @ src_ip_addr : [in] source IP address (pseudo header).
331	// @ dst_ip_addr : [in] destination IP address (pseudo header).
332	// @ is_tcp : [in] TCP if true / UDP if false (pseudo header).
333	// @ return the checksum value on 16 bits
334	////////////////////////////////////////////////////////////////////////////////////////
335	static uint16_t dev_nic_tcp_udp_checksum( uint8_t * buffer,
336	uint32_t length,
337	uint32_t src_ip_addr,
338	uint32_t dst_ip_addr,
339	bool_t is_tcp )
340	{
341	uint32_t i;
342	uint32_t carry;
343	uint32_t cs; // 32 bits accumulator
344	uint16_t * buf;
345	uint32_t max; // number of uint16_t in segment/paket
346
347	// compute max & buf
348	buf = (uint16_t *)buffer;
349	max = length >> 1;
350
351	// extend buffer[] if required
352	if( length & 1 )
353	{
354	max++;
355	buffer[length] = 0;
356	}
357
358	// compute checksum for TCP segment
359	for( i = 0 , cs = 0 ; i < max ; i++ ) cs += buf[i];
360
361	// complete checksum for pseudo-header
362	cs += (src_ip_addr & 0xFFFF);
363	cs += (src_ip_addr >> 16 );
364	cs += (dst_ip_addr & 0xFFFF);
365	cs += (dst_ip_addr >> 16 );
366	cs += length;
367	cs += (is_tcp ? PROTOCOL_TCP : PROTOCOL_UDP);
368
369	// handle carry
370	carry = (cs >> 16);
371	if( carry )
372	{
373	cs += carry;
374	carry = (cs >> 16);
375	if( carry ) cs += carry;
376	}
377
378	// one's complement
379	return ~cs;
380	}
381
382	///////////////////////////////////////////////////////////////////////////////////////////
383	// This static function is called by the NIC_TX and NIC_RX server threads to unblock
384	// the TX client thread after completion (success or error) of a TX command registered
385	// in a socket identified by the <socket_xp> argument.
386	// The <status> argument defines the command success/failure status.
387	// For all commands, it copies the status value in the tx_sts field, and print an error
388	// message on TXT0 in case of failure.
389	///////////////////////////////////////////////////////////////////////////////////////////
390	// @ socket_xp : [in] extended pointer on socket
391	// @ status : [in] command status (see above)
392	///////////////////////////////////////////////////////////////////////////////////////////
393	static void dev_nic_unblock_tx_client( xptr_t socket_xp,
394	int32_t status )
395	{
396	// get socket thread cluster and local pointer
397	socket_t * socket_ptr = GET_PTR( socket_xp );
398	cxy_t socket_cxy = GET_CXY( socket_xp );
399
400	if( (status != CMD_STS_SUCCESS) && (status != CMD_STS_EOF) )
401	{
402	uint32_t sock_state = hal_remote_l32( XPTR( socket_cxy , &socket_ptr->state ));
403	uint32_t cmd_type = hal_remote_l32( XPTR( socket_cxy , &socket_ptr->tx_cmd ));
404	pid_t pid = hal_remote_l32( XPTR( socket_cxy , &socket_ptr->pid ));
405	fdid_t fdid = hal_remote_l32( XPTR( socket_cxy , &socket_ptr->fdid ));
406
407	printk("\n[WARNING] reported by %s : socket[%x,%d] / %s / cmd %s / status %s \n",
408	__FUNCTION__, pid, fdid, socket_state_str(sock_state),
409	socket_cmd_type_str(cmd_type), socket_cmd_sts_str(status) );
410	}
411
412	// set tx_sts field in socket descriptor
413	hal_remote_s32( XPTR( socket_cxy , &socket_ptr->tx_sts ) , status );
414
415	// get extended point on TX client thread
416	xptr_t client_xp = hal_remote_l64( XPTR( socket_cxy , &socket_ptr->tx_client ));
417
418	// unblock the client thread
419	thread_unblock( client_xp , THREAD_BLOCKED_IO );
420
421	} // end dev_nic_unblock_tx_client()
422
423
424	///////////////////////////////////////////////////////////////////////////////////////////
425	// Functions called by the NIC_RX server thread
426	///////////////////////////////////////////////////////////////////////////////////////////
427
428	///////////////////////////////////////////////////////////////////////////////////////////
429	// This static function is called by the NIC_RX server threads to unblock
430	// the RX client thread after completion (success or error) of an RX command registered
431	// in a socket identified by the <socket_xp> argument.
432	// The <status> argument defines the command success/failure status.
433	// For all commands, it copies the status value in the rx_sts field, and print an error
434	// message on TXT0 in case of failure.
435	///////////////////////////////////////////////////////////////////////////////////////////
436	// @ socket_xp : [in] extended pointer on socket
437	// @ status : [in] command status (see above)
438	///////////////////////////////////////////////////////////////////////////////////////////
439	static void dev_nic_unblock_rx_client( xptr_t socket_xp,
440	int32_t status )
441	{
442	// get socket thread cluster and local pointer
443	socket_t * socket_ptr = GET_PTR( socket_xp );
444	cxy_t socket_cxy = GET_CXY( socket_xp );
445
446	if( (status != CMD_STS_SUCCESS) && (status != CMD_STS_EOF) )
447	{
448	uint32_t sock_state = hal_remote_l32( XPTR( socket_cxy , &socket_ptr->state ));
449	uint32_t cmd_type = hal_remote_l32( XPTR( socket_cxy , &socket_ptr->rx_cmd ));
450	pid_t pid = hal_remote_l32( XPTR( socket_cxy , &socket_ptr->pid ));
451	fdid_t fdid = hal_remote_l32( XPTR( socket_cxy , &socket_ptr->fdid ));
452
453	printk("\n[WARNING] reported by %s : socket[%x,%d] / %s / cmd %s / status %s\n",
454	__FUNCTION__, pid, fdid, socket_state_str(sock_state),
455	socket_cmd_type_str(cmd_type), socket_cmd_sts_str(status) );
456	}
457
458	// set rx_sts field in socket descriptor
459	hal_remote_s32( XPTR( socket_cxy , &socket_ptr->rx_sts ) , status );
460
461	// get extended point on RX client thread
462	xptr_t client_xp = hal_remote_l64( XPTR( socket_cxy , &socket_ptr->rx_client ));
463
464	// unblock the client thread
465	thread_unblock( client_xp , THREAD_BLOCKED_IO );
466
467	} // end dev_nic_unblock_rx_client()
468
469	///////////////////////////////////////////////////////////////////////////////////////////
470	// This static function is called by the dev_nic_rx_server() function.
471	// It analyses an Ethernet frame contained in the kernel buffer defined
472	// by the <buffer> argument, and returns in the <ip_length> argument the length
473	// of the IP packet contained in the Ethernet packet payload.
474	///////////////////////////////////////////////////////////////////////////////////////////
475	// @ buffer : [in] pointer on a received Ethernet packet
476	// @ ip_length : [out] length of IP packet (in bytes).
477	// @ return 0 if success / return -1 if illegal packet length.
478	///////////////////////////////////////////////////////////////////////////////////////////
479	static error_t dev_nic_rx_check_eth( uint8_t * buffer,
480	uint32_t * ip_length )
481	{
482	uint32_t length = ((uint32_t)buffer[12] << 8) \| (uint32_t)buffer[13];
483
484	*ip_length = length;
485
486	return 0;
487	}
488
489	///////////////////////////////////////////////////////////////////////////////////////////
490	// This static function analyses the IP packet contained in the kernel buffer
491	// defined by the <buffer> argument, and returns in the <ip_src_addr>, <ip_dst_addr>,
492	// <header_length> and <protocol> arguments the informations contained in the IP header.
493	// It checks the IP packet length versus the value contained in Ethernet header.
494	// It checks the IP header checksum.
495	///////////////////////////////////////////////////////////////////////////////////////////
496	// @ buffer : [in] pointer on the IP packet.
497	// @ expected_length : [in] expected IP packet length (from Ethernet header).
498	// @ ip_src_addr : [out] source IP address.
499	// @ ip_dst_addr : [out] destination IP address.
500	// @ protocol : [out] transport protocol type.
501	// @ return 0 if success / return -1 if illegal packet.
502	///////////////////////////////////////////////////////////////////////////////////////////
503	static error_t dev_nic_rx_check_ip( uint8_t * buffer,
504	uint32_t expected_length,
505	uint32_t * ip_src_addr,
506	uint32_t * ip_dst_addr,
507	uint32_t * trsp_protocol )
508	{
509
510	#if DEBUG_DEV_NIC_RX
511	thread_t * this = CURRENT_THREAD;
512	uint32_t cycle = (uint32_t)hal_get_cycles();
513	#endif
514
515	// get packet length
516	uint32_t length = ((uint32_t)buffer[2] << 8) \| (uint32_t)buffer[3];
517
518	// discard packet if eth_payload_length != ip_length
519	if( length != expected_length )
520	{
521
522	#if DEBUG_DEV_NIC_RX
523	if( DEBUG_DEV_NIC_RX < cycle )
524	printk("\n[%s] thread[%x,%x] failure : length (%d) != expected_length (%d)\n",
525	__FUNCTION__, this->process->pid, this->trdid, length, expected_length );
526	#endif
527	return -1;
528	}
529
530	// get transport protocol type
531	uint8_t protocol = buffer[9];
532
533	// discard packet if unsupported protocol
534	if( (protocol != PROTOCOL_TCP) && (protocol != PROTOCOL_UDP) )
535	{
536
537	#if DEBUG_DEV_NIC_RX
538	if( DEBUG_DEV_NIC_RX < cycle )
539	printk("\n[%s] thread[%x,%x] failure : unsupported transport protocol (%d)\n",
540	__FUNCTION__, this->process->pid, this->trdid, protocol );
541	#endif
542	return -1;
543
544	}
545	// compute IP header checksum
546	uint32_t computed_cs = (uint32_t)dev_nic_ip_checksum( buffer );
547
548	// extract IP header checksum
549	uint32_t received_cs = ((uint32_t)buffer[10] << 8) \| ((uint32_t)buffer[11]);
550
551	// discard packet if bad checksum
552	if( received_cs != computed_cs )
553	{
554
555	#if DEBUG_DEV_NIC_RX
556	if( DEBUG_DEV_NIC_RX < cycle )
557	printk("\n[%s] thread[%x,%x] failure : computed checksum (%d) != received checksum (%d)\n",
558	__FUNCTION__, this->process->pid, this->trdid, computed_cs, received_cs );
559	#endif
560	return -1;
561	}
562
563
564	*ip_src_addr = ((uint32_t)buffer[12] << 24) \|
565	((uint32_t)buffer[13] << 16) \|
566	((uint32_t)buffer[14] << 8) \|
567	((uint32_t)buffer[15] ) ;
568
569	*ip_dst_addr = ((uint32_t)buffer[16] << 24) \|
570	((uint32_t)buffer[17] << 16) \|
571	((uint32_t)buffer[18] << 8) \|
572	((uint32_t)buffer[19] ) ;
573
574	*trsp_protocol = protocol;
575
576	return 0;
577
578	} // end dev_nic_rx_check_ip()
579
580	///////////////////////////////////////////////////////////////////////////////////////////
581	// This static function analyses the UDP packet contained in the kernel buffer
582	// defined by the <k_buf> and <k_length> arguments.
583	// It checks the UDP checksum, and discard corrupted packets.
584	// It scans the list of sockets attached to the NIC_RX chdev to find a matching socket,
585	// and discard the received packet if no UDP socket found.
586	// Finally, it copies the payload to the socket "rx_buf", as long as the packet payload
587	// is not larger than the rx_buf.
588	// It set the "rx_valid" flip-flop, and unblock the client thread when the last expected
589	// byte has been received.
590	///////////////////////////////////////////////////////////////////////////////////////////
591	// @ chdev : [in] local pointer on local NIC_RX chdev descriptor.
592	// @ k_buf : [in] pointer on the UDP packet in local kernel buffer.
593	// @ k_length : [in] number of bytes in buffer (including UDP header).
594	// @ pkt_src_addr : [in] source IP address (from IP packet header).
595	// @ pkt_dst_addr : [in] destination IP address (from IP packet header).
596	///////////////////////////////////////////////////////////////////////////////////////////
597	static void dev_nic_rx_handle_udp_packet( chdev_t * chdev,
598	uint8_t * k_buf,
599	uint32_t k_length,
600	uint32_t pkt_src_addr,
601	uint32_t pkt_dst_addr )
602	{
603	xptr_t root_xp; // extended pointer on attached sockets list root
604	xptr_t lock_xp; // extended pointer on chdev lock
605	xptr_t iter_xp; // iterator on socket list
606	xptr_t socket_xp; // extended pointer on socket descriptor
607	cxy_t socket_cxy;
608	socket_t * socket_ptr;
609	uint32_t socket_type; // socket type
610	uint32_t socket_state; // socket state
611	uint32_t local_addr; // local IP address from socket
612	uint32_t local_port; // local port from socket
613	uint32_t remote_addr; // remote IP address from socket
614	uint32_t remote_port; // remote port from socket
615	bool_t match_socket; // matching socket found
616	uint16_t checksum; // computed checksum
617	uint16_t pkt_checksum; // received checksum
618	xptr_t socket_rbuf_xp; // extended pointer on socket rx_buf
619	xptr_t socket_lock_xp; // extended pointer on socket lock
620	xptr_t socket_rx_client; // socket rx_client thread
621	bool_t socket_rx_valid; // socket rx_command valid
622	uint32_t socket_rx_cmd; // socket rx_command type
623	uint32_t payload; // number of bytes in payload
624	uint32_t status; // number of bytes in rx_buf
625	uint32_t space; // number of free slots in rx_buf
626	uint32_t moved_bytes; // number of bytes actually moved to rx_buf
627
628	#if DEBUG_DEV_NIC_RX \|\| DEBUG_DEV_NIC_ERROR
629	thread_t * this = CURRENT_THREAD;
630	uint32_t cycle = (uint32_t)hal_get_cycles();
631	#endif
632
633	#if DEBUG_DEV_NIC_RX
634	uint32_t fdid;
635	uint32_t pid;
636	if( DEBUG_DEV_NIC_RX < cycle )
637	printk("\n[%s] thread[%x,%x] enter / channel %d / plen %d / cycle %d\n",
638	__FUNCTION__, this->process->pid, this->trdid, chdev->channel, k_length, cycle );
639	if( (DEBUG_DEV_NIC_RX < cycle) && (DEBUG_DEV_NIC_RX & 1))
640	putb("64 first bytes in k_buf" , k_buf , 64 );
641	#endif
642
643	// build extended pointers on list of sockets attached to NIC_RX chdev
644	root_xp = XPTR( local_cxy , &chdev->wait_root );
645	lock_xp = XPTR( local_cxy , &chdev->wait_lock );
646
647	// extract checksum from received UDP packet header
648	pkt_checksum = ((uint16_t)k_buf[6] << 8) \| (uint16_t)k_buf[7];
649
650	// reset checksum field
651	k_buf[6] = 0;
652	k_buf[7] = 0;
653
654	// compute checksum from received UDP packet
655	checksum = dev_nic_tcp_udp_checksum( k_buf,
656	k_length,
657	pkt_src_addr,
658	pkt_dst_addr,
659	false ); // is_not_tcp
660	// discard corrupted packet
661	if( pkt_checksum != checksum )
662	{
663
664	#if DEBUG_DEV_NIC_ERROR
665	printk("\n[WARNING] in %s : thread[%x,%x] discard corrupted packet on channel %d / cycle %d\n"
666	" expected checksum %x / received checksum %x\n",
667	__FUNCTION__, this->process->pid, this->trdid, chdev->channel, cycle,
668	(uint32_t)checksum, (uint32_t)pkt_checksum );
669	#endif
670	return;
671	}
672
673	// get src_port and dst_port from UDP header
674	uint32_t pkt_src_port = ((uint32_t)k_buf[0] << 8) \| (uint32_t)k_buf[1];
675	uint32_t pkt_dst_port = ((uint32_t)k_buf[2] << 8) \| (uint32_t)k_buf[3];
676
677	// take the lock protecting the sockets list
678	remote_busylock_acquire( lock_xp );
679
680	match_socket = false;
681
682	// scan sockets list to find a match
683	XLIST_FOREACH( root_xp , iter_xp )
684	{
685	// get socket cluster and local pointer
686	socket_xp = XLIST_ELEMENT( iter_xp , socket_t , rx_list );
687	socket_ptr = GET_PTR( socket_xp );
688	socket_cxy = GET_CXY( socket_xp );
689
690	// get socket type
691	socket_type = hal_remote_l32(XPTR(socket_cxy , &socket_ptr->type ));
692	socket_state = hal_remote_l32(XPTR(socket_cxy , &socket_ptr->state ));
693
694	// skip TCP socket
695	if( socket_type == SOCK_STREAM ) continue;
696
697	// get relevant info from socket descriptor
698	local_addr = hal_remote_l32(XPTR(socket_cxy , &socket_ptr->local_addr ));
699	remote_addr = hal_remote_l32(XPTR(socket_cxy , &socket_ptr->remote_addr ));
700	local_port = hal_remote_l32(XPTR(socket_cxy , &socket_ptr->local_port ));
701	remote_port = hal_remote_l32(XPTR(socket_cxy , &socket_ptr->remote_port ));
702
703	// compute matching
704	bool_t local_match = (local_addr == pkt_dst_addr) &&
705	(local_port == pkt_dst_port);
706
707	bool_t remote_match = (remote_addr == pkt_src_addr) &&
708	(remote_port == pkt_src_port);
709
710	if (socket_state == UDP_STATE_ESTAB ) match_socket = local_match && remote_match;
711	else match_socket = local_match;
712
713	// exit loop if matching
714	if( match_socket )
715	{
716
717	#if DEBUG_DEV_NIC_RX
718	fdid = hal_remote_l32( XPTR( socket_cxy , &socket_ptr->fdid ) );
719	pid = hal_remote_l32( XPTR( socket_cxy , &socket_ptr->pid ) );
720	if( DEBUG_DEV_NIC_RX < cycle )
721	printk("\n[%s] thread[%x,%x] found matching UDP socket[%d,%d] / state %s\n",
722	__FUNCTION__, this->process->pid, this->trdid, pid, fdid, socket_state_str(socket_state) );
723	#endif
724	break;
725	}
726	}
727
728	// release the lock protecting the sockets list
729	remote_busylock_release( lock_xp );
730
731	// discard unexpected packet
732	if( match_socket == false )
733	{
734
735	#if DEBUG_DEV_NIC_ERROR
736	printk("\n[WARNING] in %s : thread[%x,%s] discard unexpected packet on channel %d / cycle %d\n",
737	__FUNCTION__, this->process->pid, this->trdid, chdev->channel, cycle );
738	#endif
739	return;
740	}
741
742	// build extended pointers on socket.rx_buf and socket.lock
743	socket_rbuf_xp = XPTR( socket_cxy , &socket_ptr->rx_buf );
744	socket_lock_xp = XPTR( socket_cxy , &socket_ptr->lock );
745
746	// take the lock protecting the socket
747	remote_queuelock_acquire( socket_lock_xp );
748
749	// get status & space from rx_buf
750	status = remote_buf_status( socket_rbuf_xp );
751	space = (1 << CONFIG_SOCK_RX_BUF_ORDER) - status;
752
753	// get socket rx_client, rx_valid and rx_cmd values
754	socket_rx_client = hal_remote_l64( XPTR( socket_cxy , &socket_ptr->rx_client ) );
755	socket_rx_valid = hal_remote_l32( XPTR( socket_cxy , &socket_ptr->rx_valid ) );
756	socket_rx_cmd = hal_remote_l32( XPTR( socket_cxy , &socket_ptr->rx_cmd ) );
757
758	// get number of bytes in payload
759	payload = k_length - UDP_HEAD_LEN;
760
761	// compute number of bytes to move : min (space , seg_payload)
762	moved_bytes = ( space < payload ) ? space : payload;
763
764	// move payload from kernel buffer to socket rx_buf
765	remote_buf_put_from_kernel( socket_rbuf_xp,
766	k_buf + UDP_HEAD_LEN,
767	moved_bytes );
768	#if DEBUG_DEV_NIC_RX
769	if( DEBUG_DEV_NIC_RX < cycle )
770	printk("\n[%s] thread[%x,%x] for socket[%d,%d] move %d bytes to rx_buf / buf_sts %d\n",
771	__FUNCTION__, this->process->pid, this->trdid, pid, fdid,
772	moved_bytes, remote_buf_status(socket_rbuf_xp), moved_bytes );
773	#endif
774
775	// signal client thread if pending RECV command
776	if( (socket_rx_valid == true) && (socket_rx_cmd == CMD_RX_RECV) )
777	{
778	// reset rx_valid
779	hal_remote_s32( XPTR(socket_cxy , &socket_ptr->rx_valid), false );
780
781	// report success to RX client thread
782	dev_nic_unblock_rx_client( socket_xp , CMD_STS_SUCCESS );
783
784	#if DEBUG_DEV_NIC_RX
785	if( DEBUG_DEV_NIC_RX < cycle )
786	printk("\n[%s] thread[%x,%x] for UDP socket[%x,%d] / unblock client thread\n",
787	__FUNCTION__, this->process->pid, this->trdid, pid, fdid );
788	#endif
789
790	}
791	else
792	{
793
794	#if DEBUG_DEV_NIC_RX
795	if( DEBUG_DEV_NIC_RX < cycle )
796	printk("\n[%s] thread[%x,%x] for socket[%x,%d] / no client thread\n"
797	" rx_valid %d / rx_cmd %s\n",
798	__FUNCTION__, this->process->pid, this->trdid, pid, fdid,
799	socket_rx_valid , socket_cmd_type_str(socket_rx_cmd) );
800	#endif
801
802	}
803
804	// release the lock protecting the socket
805	remote_queuelock_release( socket_lock_xp );
806
807	} // end dev_nic_rx_handle_udp_packet()
808
809	///////////////////////////////////////////////////////////////////////////////////////////
810	// This static function is called by the dev_nic_rx_server() function to handle one RX
811	// TCP segment contained in a kernel buffer defined by the <k_buf> & <k_length> arguments.
812	// The <seg_remote_addr> and <seg_local_addr> arguments have been extracted from the IP
813	// IP header. The local and remote ports are obtained from the TCP header.
814	// It the received segment doesn't match any connected socket attached to the selected
815	// <chdev>, or any listening socket waiting connection, or if the segment is corrupted,
816	// the segment is discarded. This function implement the TCP error recovery protocol,
817	// as specified by the RFC. Depending on both the socket state, and the segment header:
818	// - it register data in the RX buffer,
819	// - it update the socket state and TCB,
820	// - it register acknolegce requests in the R2T queue,
821	// - it register connection requests in the CRQ queue,
822	///////////////////////////////////////////////////////////////////////////////////////////
823	// Implementation note:
824	// A "connected" socket is actually a TCP socket already attached to a given NIC_RX[k]
825	// chdev, and can therefore receive a TCP segment on the NIC channel <k>. A "listening"
826	// socket is a TCP socket in the LISTEN state. This function operates in 6 steps:
827	// 1) It checks the TCP checksum, and discard the corrupted segment if corrupted.
828	// 2) It scans the list of sockets attached to the NIC_RX[k] chdev, to find one TCP
829	// socket matching the TCP segment header.
830	// 3) When a matching connected socket is found, it handles the received segment, including
831	// the SYN, FIN, ACK and RST flags. It updates the socket state when required, moves
832	// data to the rx_buf when possible, and return. It takes the lock protecting the socket,
833	// because a connected socket is accessed by both the NIC_TX and NIC_RX server threads.
834	// 4) If no matching connected socket has been found, it scans the list of listening
835	// sockets to find a matching listening socket.
836	// 5) When a matching listening socket is found, it simply registers a new connection
837	// request in the listening socket CRQ queue, when the SYN flag is set, and insert
838	// a SYN-ACK request in the socket R2T queue.
839	// 6) It discards the packet if no connected or listening socket has been found.
840	///////////////////////////////////////////////////////////////////////////////////////////
841	// @ chdev : [in] local pointer on local NIC_RX chdev descriptor.
842	// @ k_buf : [in] pointer on the TCP packet in local kernel buffer.
843	// @ k_length : [in] number of bytes in buffer (including TCP header).
844	// @ seg_remote_addr : [in] remote IP address (from IP packet header).
845	// @ seg_local_addr : [in] local IP address (from IP packet header).
846	///////////////////////////////////////////////////////////////////////////////////////////
847	static void dev_nic_rx_handle_tcp_segment( chdev_t * chdev,
848	uint8_t * k_buf,
849	uint32_t k_length,
850	uint32_t seg_remote_addr,
851	uint32_t seg_local_addr )
852	{
853	xptr_t root_xp; // extended pointer on connected sockets list root
854	xptr_t lock_xp; // extended pointer on chdev lock
855	xptr_t iter_xp; // iterator for these queues
856	bool_t attached_match; // true if one attached socket match
857	bool_t listening_match; // true if one listening socket match
858	xptr_t socket_xp; // extended pointer on matching socket
859	cxy_t socket_cxy; // cluster identifier of matching socket
860	socket_t * socket_ptr; // local pointer on matching socket
861	uint32_t socket_local_addr; // local IP address from socket
862	uint32_t socket_local_port; // local port from socket
863	uint32_t socket_remote_addr; // remote IP address from socket
864	uint32_t socket_remote_port; // remote port from socket
865	uint32_t socket_state; // socket state
866	uint32_t socket_type; // socket type
867	bool_t socket_tx_valid; // TX command valid
868	uint32_t socket_tx_cmd; // TX command type
869	uint32_t socket_tx_nxt; // next byte to send in TX stream
870	uint32_t socket_tx_una; // first unacknowledged byte in TX stream
871	uint32_t socket_tx_len; // number of bytes in tx_buf
872	uint32_t socket_tx_ack; // number of acknowledged bytes in tx_buf
873	bool_t socket_rx_valid; // RX command valid
874	uint32_t socket_rx_cmd; // TX command type
875	uint32_t socket_rx_nxt; // next expected byte in RX stream
876	uint32_t socket_rx_wnd; // current window value in RX stream
877	uint32_t socket_rx_irs; // initial sequence index in RX stream
878	xptr_t socket_lock_xp; // extended pointer on lock protecting socket state
879	xptr_t socket_rx_buf_xp; // extended pointer on socket rx_buf
880	xptr_t socket_r2tq_xp; // extended pointer on socket R2T queue
881	xptr_t socket_crqq_xp; // extended pointer on socket CRQ queue
882	uint16_t checksum; // computed TCP segment chechsum
883	error_t error;
884
885	// get relevant infos from TCP segment header
886	uint32_t seg_remote_port = ((uint32_t)k_buf[0] << 8) \| (uint32_t)k_buf[1];
887	uint32_t seg_local_port = ((uint32_t)k_buf[2] << 8) \| (uint32_t)k_buf[3];
888
889	uint32_t seg_seq_num = ((uint32_t)k_buf[4] << 24) \|
890	((uint32_t)k_buf[5] << 16) \|
891	((uint32_t)k_buf[6] << 8) \|
892	((uint32_t)k_buf[7] );
893
894	uint32_t seg_ack_num = ((uint32_t)k_buf[8] << 24) \|
895	((uint32_t)k_buf[9] << 16) \|
896	((uint32_t)k_buf[10] << 8) \|
897	((uint32_t)k_buf[11] );
898
899	uint8_t seg_hlen = k_buf[12] << 2; // TCP header length in bytes
900
901	uint8_t seg_flags = k_buf[13];
902
903	bool_t seg_ack_set = ((seg_flags & TCP_FLAG_ACK) != 0);
904	bool_t seg_syn_set = ((seg_flags & TCP_FLAG_SYN) != 0);
905	bool_t seg_fin_set = ((seg_flags & TCP_FLAG_FIN) != 0);
906	bool_t seg_rst_set = ((seg_flags & TCP_FLAG_RST) != 0);
907
908	uint16_t seg_window = ((uint32_t)k_buf[14] << 8) \| (uint32_t)k_buf[15];
909
910	uint16_t seg_checksum = ((uint32_t)k_buf[16] << 8) \| (uint32_t)k_buf[17];
911
912	uint32_t seg_data_len = k_length - seg_hlen; // number of bytes in payload
913
914	uint32_t seg_data_dup; // number of duplicated bytes in payload
915	uint32_t seg_data_new; // number of new bytes in payload
916
917	#if DEBUG_DEV_NIC_RX \|\| DEBUG_DEV_NIC_ERROR
918	uint32_t fdid;
919	pid_t pid;
920	thread_t * this = CURRENT_THREAD;
921	uint32_t cycle = (uint32_t)hal_get_cycles();
922	#endif
923
924	#if DEBUG_DEV_NIC_RX
925	if( DEBUG_DEV_NIC_RX < cycle )
926	printk("\n[%s] thread[%x,%x] enters / tcp_length %d / tcp_flags %x / cycle %d\n",
927	__FUNCTION__, this->process->pid, this->trdid, k_length, seg_flags , cycle );
928	#endif
929
930	// reset checksum field
931	k_buf[16] = 0;
932	k_buf[17] = 0;
933
934	// compute TCP checksum
935	checksum = dev_nic_tcp_udp_checksum( k_buf,
936	k_length,
937	seg_remote_addr,
938	seg_local_addr,
939	true ); // is_tcp
940	// discard segment if corrupted
941	if( seg_checksum != checksum )
942	{
943
944	#if DEBUG_DEV_NIC_ERROR
945	printk("\n[WARNING] in %s : thread[%x,%x] / checksum failure on channel %d / cycle %d\n",
946	__FUNCTION__, this->process->pid, this->trdid, chdev->channel, cycle );
947	#endif
948	return;
949	}
950
951	// build extended pointer on xlist of sockets attached to NIC_RX chdev
952	root_xp = XPTR( local_cxy , &chdev->wait_root );
953	lock_xp = XPTR( local_cxy , &chdev->wait_lock );
954
955	attached_match = false;
956
957	// take the lock protecting the list of attached sockets
958	remote_busylock_acquire( lock_xp );
959
960	// scan list of attached sockets to find a matching TCP socket
961	XLIST_FOREACH( root_xp , iter_xp )
962	{
963	// get socket cluster and local pointer
964	socket_xp = XLIST_ELEMENT( iter_xp , socket_t , rx_list );
965	socket_ptr = GET_PTR( socket_xp );
966	socket_cxy = GET_CXY( socket_xp );
967
968	// get socket type and state
969	socket_type = hal_remote_l32(XPTR(socket_cxy , &socket_ptr->type ));
970	socket_state = hal_remote_l32(XPTR(socket_cxy , &socket_ptr->state ));
971
972	// skip UDP socket
973	if( socket_type == SOCK_DGRAM ) continue;
974
975	// get relevant socket infos for matching
976	socket_local_addr = hal_remote_l32(XPTR(socket_cxy , &socket_ptr->local_addr ));
977	socket_remote_addr = hal_remote_l32(XPTR(socket_cxy , &socket_ptr->remote_addr ));
978	socket_local_port = hal_remote_l32(XPTR(socket_cxy , &socket_ptr->local_port ));
979	socket_remote_port = hal_remote_l32(XPTR(socket_cxy , &socket_ptr->remote_port ));
980
981	// compute matching condition for a connected socket
982	attached_match = (socket_local_addr == seg_local_addr) &&
983	(socket_local_port == seg_local_port) &&
984	(socket_remote_addr == seg_remote_addr) &&
985	(socket_remote_port == seg_remote_port) ;
986
987	// exit loop if matching
988	if( attached_match )
989	{
990
991	#if DEBUG_DEV_NIC_RX \|\| DEBUG_DEV_NIC_ERROR
992	fdid = hal_remote_l32( XPTR( socket_cxy , &socket_ptr->fdid ) );
993	pid = hal_remote_l32( XPTR( socket_cxy , &socket_ptr->pid ) );
994	#endif
995
996	#if DEBUG_DEV_NIC_RX
997	if( DEBUG_DEV_NIC_RX < cycle )
998	printk("\n[%s] matching attached TCP socket[%d,%d] / state %s\n",
999	__FUNCTION__, pid, fdid, socket_state_str(socket_state) );
1000	#endif
1001	break;
1002	}
1003
1004	} // end loop on attached sockets
1005
1006	// release the lock protecting the list of attached sockets
1007	remote_busylock_release( lock_xp );
1008
1009	// handle TCP segment for an attached socket
1010	if( attached_match )
1011	{
1012	// The actions depend on both the socket state and the received segment flags :
1013	// - update socket state,
1014	// - move data to rx_buf,
1015	// - register a request in R2T queue when required
1016
1017	// build extended pointers on various socket fields
1018	socket_lock_xp = XPTR( socket_cxy , &socket_ptr->lock );
1019	socket_rx_buf_xp = XPTR( socket_cxy , &socket_ptr->rx_buf );
1020	socket_r2tq_xp = XPTR( socket_cxy , &socket_ptr->r2tq );
1021
1022	// take the lock protecting the matching socket
1023	remote_queuelock_acquire( socket_lock_xp );
1024
1025	// get relevant socket infos from socket descriptor
1026	socket_tx_valid = hal_remote_l32(XPTR( socket_cxy , &socket_ptr->tx_valid ));
1027	socket_tx_cmd = hal_remote_l32(XPTR( socket_cxy , &socket_ptr->tx_cmd ));
1028	socket_tx_nxt = hal_remote_l32(XPTR( socket_cxy , &socket_ptr->tx_nxt ));
1029	socket_tx_una = hal_remote_l32(XPTR( socket_cxy , &socket_ptr->tx_una ));
1030	socket_tx_ack = hal_remote_l32(XPTR( socket_cxy , &socket_ptr->tx_ack ));
1031	socket_tx_len = hal_remote_l32(XPTR( socket_cxy , &socket_ptr->tx_len ));
1032
1033	socket_rx_valid = hal_remote_l32(XPTR( socket_cxy , &socket_ptr->rx_valid ));
1034	socket_rx_cmd = hal_remote_l32(XPTR( socket_cxy , &socket_ptr->rx_cmd ));
1035	socket_rx_nxt = hal_remote_l32(XPTR( socket_cxy , &socket_ptr->rx_nxt ));
1036	socket_rx_wnd = hal_remote_l32(XPTR( socket_cxy , &socket_ptr->rx_wnd ));
1037	socket_rx_irs = hal_remote_l32(XPTR( socket_cxy , &socket_ptr->rx_irs ));
1038
1039	// handle the received segment, depending on the matching socket state
1040	switch( socket_state )
1041	{
1042	////////////////////////
1043	case TCP_STATE_SYN_SENT: // TCP client waiting for SYN-ACK
1044	{
1045	// [1] & [2] check ACK and RST
1046	if( seg_ack_set )
1047	{
1048	bool_t ack_ok = (seg_ack_num == (CONFIG_SOCK_ISS_CLIENT + 1) );
1049
1050	if( seg_rst_set && ack_ok )
1051	{
1052
1053	#if DEBUG_DEV_NIC_RX
1054	if( DEBUG_DEV_NIC_RX < cycle )
1055	printk("\n[%s] socket[%x,%d] %s RST received from remote TCP => close\n",
1056	__FUNCTION__, pid, fdid, socket_state_str(socket_state) );
1057	#endif
1058	// report RST to local TCP client thread
1059	dev_nic_unblock_tx_client( socket_xp , CMD_STS_RST );
1060
1061	// update socket state
1062	hal_remote_s32( XPTR( socket_cxy , &socket_ptr->state ),
1063	TCP_STATE_BOUND );
1064	break;
1065	}
1066
1067	if( seg_rst_set && (ack_ok == false) )
1068	{
1069
1070	#if DEBUG_DEV_NIC_ERROR
1071	printk("\n[ERROR] in %s : socket[%x,%d] %s RST but expect ack_num %x != rcvd %x => discard\n",
1072	__FUNCTION__, pid, fdid, socket_state_str(socket_state),
1073	CONFIG_SOCK_ISS_CLIENT + 1, seg_ack_num );
1074	#endif
1075	break;
1076	}
1077
1078	if( (seg_rst_set == false) && (ack_ok == false) )
1079	{
1080
1081	#if DEBUG_DEV_NIC_ERROR
1082	printk("\n[ERROR] in %s : socket[%x,%d] %s expected ack_num %x != rcvd %x => send RST\n",
1083	__FUNCTION__, pid, fdid, socket_state_str(socket_state),
1084	CONFIG_SOCK_ISS_CLIENT + 1, seg_ack_num );
1085	#endif
1086	// send RST to remote TCP
1087	socket_put_r2t_request( socket_r2tq_xp,
1088	TCP_FLAG_RST,
1089	chdev->channel );
1090	break;
1091	}
1092	}
1093
1094	// [3] handle security & precedence TODO ... someday
1095
1096	// [4] handle SYN-ACK
1097	if( seg_syn_set && seg_ack_set ) // received SYN and ACK => report success
1098	{
1099
1100	#if DEBUG_DEV_NIC_RX
1101	if( DEBUG_DEV_NIC_RX < cycle )
1102	printk("\n[%s] socket[%x,%d] %s : received expected SYN-ACK\n",
1103	__FUNCTION__, pid, fdid , socket_state_str(socket_state) );
1104	#endif
1105	// set socket.tx_una
1106	hal_remote_s32( XPTR(socket_cxy , &socket_ptr->tx_una), seg_ack_num );
1107
1108	// set socket.rx_irs
1109	hal_remote_s32( XPTR(socket_cxy , &socket_ptr->rx_irs), seg_seq_num );
1110
1111	// set socket.rx_nxt
1112	hal_remote_s32( XPTR(socket_cxy , &socket_ptr->rx_nxt), seg_seq_num + 1 );
1113
1114	// update socket.state
1115	hal_remote_s32( XPTR(socket_cxy , &socket_ptr->state), TCP_STATE_ESTAB );
1116
1117	// make an ACK request to R2T queue
1118	socket_put_r2t_request( socket_r2tq_xp,
1119	TCP_FLAG_ACK,
1120	chdev->channel );
1121
1122	// report succes to local TX client thread
1123	dev_nic_unblock_tx_client( socket_xp , CMD_STS_SUCCESS );
1124	}
1125	else // SYN without ACK => TCP client becomes a TCP server
1126	{
1127
1128	#if DEBUG_DEV_NIC_RX
1129	if( DEBUG_DEV_NIC_RX < cycle )
1130	printk("\n[%s] socket[%x,%d] %s : received SYN without ACK => send a SYN_ACK\n",
1131	__FUNCTION__, pid, fdid , socket_state_str(socket_state) );
1132	#endif
1133	// update socket.state
1134	hal_remote_s32( XPTR(socket_cxy,&socket_ptr->state),
1135	TCP_STATE_SYN_RCVD );
1136
1137	// set socket.tx_nxt
1138	hal_remote_s32( XPTR(socket_cxy , &socket_ptr->tx_nxt),
1139	CONFIG_SOCK_ISS_SERVER );
1140
1141	// set socket.rx_nxt to seg_seq_num + 1
1142	hal_remote_s32( XPTR(socket_cxy,&socket_ptr->rx_nxt), seg_seq_num + 1 );
1143
1144	// send SYN.ACK to remote TCP
1145	socket_put_r2t_request( socket_r2tq_xp,
1146	TCP_FLAG_SYN \| TCP_FLAG_ACK,
1147	chdev->channel );
1148	}
1149	break;
1150	} // end state SYN_SENT
1151
1152	//////////////////////// all "connected" states
1153	case TCP_STATE_SYN_RCVD:
1154	case TCP_STATE_ESTAB:
1155	case TCP_STATE_FIN_WAIT1:
1156	case TCP_STATE_FIN_WAIT2:
1157	case TCP_STATE_CLOSE_WAIT:
1158	case TCP_STATE_CLOSING:
1159	case TCP_STATE_LAST_ACK:
1160	case TCP_STATE_TIME_WAIT:
1161	{
1162	// [1] check SEQ_NUM
1163	// - we accept duplicate segments (i.e. seq_num < rx_next)
1164	// - we don't accept out of order segment (i.e. seq_num_num > rx_next)
1165	// => seq_num must be in window [rx_nxt - rx_win , rx_nxt]
1166
1167	bool_t seq_ok = is_in_window( seg_seq_num,
1168	(socket_rx_nxt - socket_rx_wnd),
1169	socket_rx_nxt );
1170
1171	if( seq_ok == false ) // SEQ_NUM not acceptable
1172	{
1173	if( seg_rst_set )
1174	{
1175
1176	#if DEBUG_DEV_NIC_ERROR
1177	printk("\n[ERROR] in %s : socket[%x,%d] %s expect seq_num %x != rcvd %x and RST => discard\n",
1178	__FUNCTION__, pid, fdid, socket_state_str(socket_state),
1179	CONFIG_SOCK_ISS_CLIENT + 1, seg_seq_num );
1180	#endif
1181	break;
1182	}
1183	else // no RST
1184	{
1185	// send ACK to remote TCP
1186	socket_put_r2t_request( socket_r2tq_xp,
1187	TCP_FLAG_ACK,
1188	chdev->channel );
1189	#if DEBUG_DEV_NIC_ERROR
1190	printk("\n[ERROR] in %s : socket[%x,%d] %s expect seq_num %x != rcvd %x => ACK and discard\n",
1191	__FUNCTION__, pid, fdid, socket_state_str(socket_state),
1192	CONFIG_SOCK_ISS_CLIENT + 1, seg_seq_num );
1193	#endif
1194	break;
1195	}
1196	}
1197	else // SEQ_NUM acceptable
1198	{
1199	// compute number of new bytes & number of duplicated bytes
1200	if( seg_seq_num != socket_rx_nxt ) // duplicate segment
1201	{
1202	seg_data_dup = socket_rx_nxt - seg_seq_num;
1203	seg_data_new = (seg_data_len > seg_data_dup) ?
1204	(seg_data_len - seg_data_dup) : 0;
1205	}
1206	else // expected segment
1207	{
1208	seg_data_dup = 0;
1209	seg_data_new = seg_data_len;
1210	}
1211
1212	#if DEBUG_DEV_NIC_RX
1213	if( DEBUG_DEV_NIC_RX < cycle )
1214	printk("\n[%s] socket[%x,%d] %s seq_num %x / rx_nxt %x / len %d / new %d / dup %d\n",
1215	__FUNCTION__, pid, fdid, socket_state_str(socket_state),
1216	seg_seq_num, socket_rx_nxt, seg_data_len, seg_data_new, seg_data_dup );
1217	#endif
1218	}
1219
1220	// [2] handle RST flag (depending on socket state)
1221	if( seg_rst_set )
1222	{
1223	if( socket_state == TCP_STATE_SYN_RCVD )
1224	{
1225
1226	#if DEBUG_DEV_NIC_RX
1227	if( DEBUG_DEV_NIC_RX < cycle )
1228	printk("\n[%s] socket[%x,%d] %s RST received from remote TCP => report to user\n",
1229	__FUNCTION__, pid, fdid, socket_state_str(socket_state) );
1230	#endif
1231	// report RST to local TX client thread
1232	dev_nic_unblock_tx_client( socket_xp , CMD_STS_RST );
1233
1234	// update socket state
1235	hal_remote_s32( XPTR(socket_cxy , &socket_ptr->state),
1236	TCP_STATE_BOUND );
1237	break;
1238	}
1239
1240	else if( (socket_state == TCP_STATE_ESTAB ) \|\|
1241	(socket_state == TCP_STATE_FIN_WAIT1 ) \|\|
1242	(socket_state == TCP_STATE_FIN_WAIT2 ) \|\|
1243	(socket_state == TCP_STATE_CLOSE_WAIT) )
1244	{
1245
1246	#if DEBUG_DEV_NIC_RX
1247	if( DEBUG_DEV_NIC_RX < cycle )
1248	printk("\n[%s] socket[%x,%d] %s / received RST flag\n",
1249	__FUNCTION__, pid, fdid, socket_state_str(socket_state) );
1250	#endif
1251	// report RST to local TX client thread
1252	if( socket_tx_valid ) dev_nic_unblock_tx_client( socket_xp,
1253	CMD_STS_RST );
1254	// report RST to local RX client thread
1255	if( socket_rx_valid ) dev_nic_unblock_rx_client( socket_xp,
1256	CMD_STS_RST );
1257	// update socket state
1258	hal_remote_s32( XPTR(socket_cxy , &socket_ptr->state),
1259	TCP_STATE_BOUND );
1260	break;
1261	}
1262	else // states CLOSING / LAST_ACK / TIME_WAIT
1263	{
1264	// update socket state
1265	hal_remote_s32( XPTR(socket_cxy , &socket_ptr->state),
1266	TCP_STATE_BOUND );
1267	break;
1268	}
1269	}
1270
1271	// [3] handle security & precedence TODO ... someday
1272
1273	// [4] check SYN
1274	if( seg_syn_set ) // received SYN => send RST to remote
1275	{
1276
1277	#if DEBUG_DEV_NIC_ERROR
1278	printk("\n[ERROR] in %s socket[%x,%d] %s : received SYN flag => send RST-ACK\n",
1279	__FUNCTION__, pid, fdid , socket_state_str(socket_state) );
1280	#endif
1281	// send RST & ACK to remote TCP
1282	socket_put_r2t_request( socket_r2tq_xp,
1283	TCP_FLAG_RST \| TCP_FLAG_ACK,
1284	chdev->channel );
1285
1286	// report RST to local TX client thread
1287	if( socket_tx_valid ) dev_nic_unblock_tx_client( socket_xp,
1288	CMD_STS_RST );
1289	// report RST to local RX client thread
1290	if( socket_rx_valid ) dev_nic_unblock_rx_client( socket_xp,
1291	CMD_STS_RST );
1292	// update socket state
1293	hal_remote_s32( XPTR(socket_cxy , &socket_ptr->state),
1294	TCP_STATE_BOUND );
1295	break;
1296	}
1297
1298	// [5] handle ACK (depending on socket state)
1299	if( seg_ack_set == false ) // missing ACK => discard segment
1300	{
1301
1302	#if DEBUG_DEV_NIC_ERROR
1303	printk("\n[ERROR] in %s : socket[%x,%d] %s / no ACK in segment => discard\n",
1304	__FUNCTION__, pid, fdid, socket_state_str(socket_state) );
1305	#endif
1306	break;
1307	}
1308
1309	// compute acceptable ACK
1310	bool_t ack_ok = is_in_window( seg_ack_num,
1311	socket_tx_una,
1312	socket_tx_nxt );
1313
1314	if( socket_state == TCP_STATE_SYN_RCVD )
1315	{
1316	if( ack_ok ) // acceptable ACK
1317	{
1318
1319	#if DEBUG_DEV_NIC_RX
1320	if( DEBUG_DEV_NIC_RX < cycle )
1321	printk("\n[%s] socket[%x,%d] %s : received expected ACK => update socket\n",
1322	__FUNCTION__, pid, fdid , socket_state_str(socket_state) );
1323	#endif
1324	// set socket.tx_una
1325	hal_remote_s32( XPTR(socket_cxy , &socket_ptr->tx_una), seg_ack_num );
1326
1327	// update socket.state
1328	hal_remote_s32( XPTR(socket_cxy , &socket_ptr->state),
1329	TCP_STATE_ESTAB );
1330
1331	// report success to local TX client thread
1332	dev_nic_unblock_tx_client( socket_xp , CMD_STS_SUCCESS );
1333	}
1334	else // send RST to remote
1335	{
1336
1337	#if DEBUG_DEV_NIC_ERROR
1338	printk("\n[ERROR] in %s : socket[%x,%d] %s / ACK %x not in [%x,%x] => discard\n",
1339	__FUNCTION__, pid, fdid, socket_state_str(socket_state),
1340	seg_ack_num, socket_tx_una, socket_tx_nxt );
1341	#endif
1342	// send RST & ACK to remote TCP
1343	socket_put_r2t_request( socket_r2tq_xp,
1344	TCP_FLAG_RST \| TCP_FLAG_ACK,
1345	chdev->channel );
1346	break;
1347	}
1348	}
1349
1350	else if( (socket_state == TCP_STATE_ESTAB) \|\|
1351	(socket_state == TCP_STATE_FIN_WAIT1) \|\|
1352	(socket_state == TCP_STATE_FIN_WAIT2) \|\|
1353	(socket_state == TCP_STATE_FIN_WAIT2) \|\|
1354	(socket_state == TCP_STATE_CLOSE_WAIT) \|\|
1355	(socket_state == TCP_STATE_CLOSING) )
1356	{
1357	if( ack_ok ) // acceptable ack
1358	{
1359	// compute number of acknowledged bytes
1360	uint32_t ack_bytes = seg_ack_num - socket_tx_una;
1361
1362	if( ack_bytes ) // handle acknowledged bytes
1363	{
1364	#if DEBUG_DEV_NIC_RX
1365	if( DEBUG_DEV_NIC_RX < cycle )
1366	printk("\n[%s] socket[%x,%d] %d bytes acknowledged => update socket\n",
1367	__FUNCTION__, pid, fdid, ack_bytes );
1368	#endif
1369	// update socket.tx_una, socket.tx_ack, and socket.tx_wnd fields
1370	hal_remote_s32( XPTR(socket_cxy , &socket_ptr->tx_una),
1371	seg_ack_num );
1372	hal_remote_s32( XPTR(socket_cxy , &socket_ptr->tx_ack),
1373	socket_tx_ack + ack_bytes );
1374	hal_remote_s32( XPTR(socket_cxy , &socket_ptr->tx_wnd),
1375	seg_window );
1376
1377	// unblock the TX client thread if last byte acknowledged
1378	if( (socket_tx_ack + ack_bytes) == socket_tx_len )
1379	{
1380	// report success to TX client thread
1381	dev_nic_unblock_tx_client( socket_xp , CMD_STS_SUCCESS );
1382	#if DEBUG_DEV_NIC_RX
1383	if( DEBUG_DEV_NIC_RX < cycle )
1384	printk("\n[%s] socket[%x,%d] %s : last ack => unblock TX client thread\n",
1385	__FUNCTION__, pid, fdid, socket_state_str(socket_state) );
1386	#endif
1387	}
1388	}
1389
1390	if( socket_state == TCP_STATE_FIN_WAIT1 )
1391	{
1392	// update socket state
1393	hal_remote_s32( XPTR(socket_cxy , &socket_ptr->state),
1394	TCP_STATE_FIN_WAIT2 );
1395	}
1396	if( socket_state == TCP_STATE_FIN_WAIT2 )
1397	{
1398	// TODO
1399	}
1400	else if( socket_state == TCP_STATE_CLOSING )
1401	{
1402	// update socket state
1403	hal_remote_s32( XPTR(socket_cxy , &socket_ptr->state),
1404	TCP_STATE_TIME_WAIT );
1405	}
1406	else if( socket_state == TCP_STATE_CLOSING )
1407	{
1408	// TODO
1409	}
1410	}
1411	else // unacceptable ACK => discard segment
1412	{
1413
1414	#if DEBUG_DEV_NIC_ERROR
1415	printk("\n[ERROR] in %s : socket[%x,%d] %s / ACK %x not in [%x,%x] => discard\n",
1416	__FUNCTION__, pid, fdid, socket_state_str(socket_state),
1417	seg_ack_num, socket_tx_una, socket_tx_nxt );
1418	#endif
1419	break;
1420	}
1421	}
1422
1423	else if( socket_state == TCP_STATE_LAST_ACK )
1424	{
1425	// TODO
1426	}
1427
1428	else if( socket_state == TCP_STATE_TIME_WAIT )
1429	{
1430	// TODO
1431	}
1432
1433	// [6] handle URG flag TODO ... someday
1434
1435	// [7] handle received data : update socket state,
1436	// move data to rx_buf, register ACK request to R2T queue,
1437	// unblock the RX client thread in case of pending RX_RECV command
1438	if((socket_state == TCP_STATE_ESTAB) \|\|
1439	(socket_state == TCP_STATE_FIN_WAIT1) \|\|
1440	(socket_state == TCP_STATE_FIN_WAIT2) )
1441	{
1442	// register new bytes if requested
1443	if( seg_data_new )
1444	{
1445	// get number of bytes already stored in rx_buf
1446	uint32_t status = remote_buf_status( socket_rx_buf_xp );
1447
1448	// compute space in rx_buf and actual number of acceptable bytes
1449	// when (space < seg_data_new) the last new bytes are discarded
1450	uint32_t space = (1 << CONFIG_SOCK_RX_BUF_ORDER) - status;
1451	uint32_t rcv_bytes = (space < seg_data_new) ? space : seg_data_new;
1452
1453	// move new bytes from k_buf to rx_buf
1454	remote_buf_put_from_kernel( socket_rx_buf_xp,
1455	k_buf + seg_hlen + seg_data_dup,
1456	rcv_bytes );
1457	#if DEBUG_DEV_NIC_RX
1458	if( DEBUG_DEV_NIC_RX < cycle )
1459	printk("\n[%s] socket[%x,%d] %s : move %d bytes to rx_buf\n",
1460	__FUNCTION__, pid, fdid, socket_state_str(socket_state), rcv_bytes );
1461	#endif
1462	// update socket.rx_nxt and socket_rx_wnd fields
1463	hal_remote_s32( XPTR( socket_cxy , &socket_ptr->rx_nxt ),
1464	socket_rx_nxt + rcv_bytes );
1465	hal_remote_s32( XPTR( socket_cxy , &socket_ptr->rx_wnd ),
1466	socket_rx_wnd - rcv_bytes );
1467
1468	// unblock RX client if required
1469	if( (socket_rx_valid == true) && (socket_rx_cmd == CMD_RX_RECV) )
1470	{
1471	// reset rx_valid
1472	hal_remote_s32( XPTR(socket_cxy,&socket_ptr->rx_valid), false );
1473
1474	// report success to RX client thread
1475	dev_nic_unblock_rx_client( socket_xp , CMD_STS_SUCCESS );
1476	#if DEBUG_DEV_NIC_RX
1477	if( DEBUG_DEV_NIC_RX < cycle )
1478	printk("\n[%s] socket[%x,%d] %s : last data => unblock RX client thread\n",
1479	__FUNCTION__, pid, fdid, socket_state_str(socket_state) );
1480	#endif
1481	}
1482	}
1483
1484	// make an ACK request to remote
1485	socket_put_r2t_request( socket_r2tq_xp,
1486	TCP_FLAG_ACK,
1487	chdev->channel );
1488	} // end payload handling
1489
1490	// [8] handle FIN flag depending on socket state
1491	if( (socket_state == TCP_STATE_SYN_RCVD) \|\|
1492	(socket_state == TCP_STATE_ESTAB ) )
1493	{
1494	if( seg_fin_set )
1495	{
1496
1497	#if DEBUG_DEV_NIC_RX
1498	if( DEBUG_DEV_NIC_RX < cycle )
1499	printk("\n[%s] socket[%x,%d] %s : FIN-ACK => goes CLOSE_WAIT\n",
1500	__FUNCTION__, pid, fdid, socket_state_str(socket_state) );
1501	#endif
1502	// update socket.rx_nxt when FIN received
1503	hal_remote_s32( XPTR( socket_cxy , &socket_ptr->rx_nxt ),
1504	socket_rx_nxt + 1 );
1505
1506	// update socket state
1507	hal_remote_s32( XPTR( socket_cxy , &socket_ptr->state ),
1508	TCP_STATE_CLOSE_WAIT );
1509
1510	// send ACK to remote TCP
1511	socket_put_r2t_request( socket_r2tq_xp,
1512	TCP_FLAG_ACK,
1513	chdev->channel );
1514
1515	// check pending RX_RECV command
1516	if( (socket_rx_valid == true) && (socket_rx_cmd == CMD_RX_RECV) )
1517	{
1518	// reset rx_valid
1519	hal_remote_s32( XPTR(socket_cxy,&socket_ptr->rx_valid), false );
1520
1521	// report FIN to RX client thread
1522	dev_nic_unblock_rx_client( socket_xp , CMD_STS_EOF );
1523	#if DEBUG_DEV_NIC_RX
1524	if( DEBUG_DEV_NIC_RX < cycle )
1525	printk("\n[%s] socket[%x,%d] %s : unblock RX client waiting on RECV\n",
1526	__FUNCTION__, pid, fdid, socket_state_str(socket_state) );
1527	#endif
1528	}
1529	}
1530	}
1531	else if( socket_state == TCP_STATE_FIN_WAIT1 )
1532	{
1533	if( seg_fin_set )
1534	{
1535
1536	#if DEBUG_DEV_NIC_RX
1537	if( DEBUG_DEV_NIC_RX < cycle )
1538	printk("\n[%s] socket[%x,%d] %s : FIN-ACK => goes CLOSING\n",
1539	__FUNCTION__, pid, fdid, socket_state_str(socket_state) );
1540	#endif
1541	// update socket.rx_nxt
1542	hal_remote_s32( XPTR( socket_cxy , &socket_ptr->rx_nxt ),
1543	socket_rx_nxt + 1 );
1544
1545	// update socket state
1546	hal_remote_s32( XPTR( socket_cxy , &socket_ptr->state ),
1547	TCP_STATE_CLOSING );
1548
1549	// send ACK request to remote
1550	socket_put_r2t_request( socket_r2tq_xp,
1551	TCP_FLAG_ACK,
1552	chdev->channel );
1553	}
1554	else // received ACK only
1555	{
1556
1557	#if DEBUG_DEV_NIC_RX
1558	if( DEBUG_DEV_NIC_RX < cycle )
1559	printk("\n[%s] socket[%x,%d] %s : only ACK => goes FIN_WAIT2\n",
1560	__FUNCTION__, pid, fdid, socket_state_str(socket_state) );
1561	#endif
1562	// update socket state
1563	hal_remote_s32( XPTR( socket_cxy , &socket_ptr->state ),
1564	TCP_STATE_FIN_WAIT2 );
1565	}
1566	}
1567	else if( socket_state == TCP_STATE_FIN_WAIT2 )
1568	{
1569	if( seg_fin_set ) // received ACK & FIN
1570	{
1571
1572	#if DEBUG_DEV_NIC_RX
1573	if( DEBUG_DEV_NIC_RX < cycle )
1574	printk("\n[%s] socket[%x,%d] %s : FIN-ACK => goes CLOSED / unblock client\n",
1575	__FUNCTION__, pid, fdid, socket_state_str(socket_state) );
1576	#endif
1577	// update socket.rx_nxt when FIN received
1578	hal_remote_s32( XPTR( socket_cxy , &socket_ptr->rx_nxt ),
1579	socket_rx_nxt + 1 );
1580
1581	// update socket.state
1582	hal_remote_s32( XPTR( socket_cxy , &socket_ptr->state ),
1583	TCP_STATE_CLOSED );
1584
1585	// make an ACK request to R2T queue
1586	socket_put_r2t_request( socket_r2tq_xp,
1587	TCP_FLAG_ACK,
1588	chdev->channel );
1589
1590	// report success to TX client thread
1591	dev_nic_unblock_tx_client( socket_xp , CMD_STS_SUCCESS );
1592	}
1593	}
1594	else if( socket_state == TCP_STATE_CLOSING ) // received ACK
1595	{
1596	// update socket.state
1597	hal_remote_s32( XPTR( socket_cxy , &socket_ptr->state ),
1598	TCP_STATE_CLOSED );
1599
1600	// report success to TX client thread
1601	dev_nic_unblock_tx_client( socket_xp , CMD_STS_SUCCESS );
1602
1603	}
1604	else if( socket_state == TCP_STATE_CLOSE_WAIT )
1605	{
1606	// do nothing
1607	}
1608	else if( socket_state == TCP_STATE_LAST_ACK )
1609	{
1610	// update socket.state when ACK received
1611	hal_remote_s32( XPTR( socket_cxy , &socket_ptr->state ),
1612	TCP_STATE_CLOSED );
1613
1614	// unblock TX client thead for success
1615	dev_nic_unblock_tx_client( socket_xp , CMD_STS_SUCCESS );
1616	}
1617	} // end case connected states
1618	} // end switch socket state
1619
1620	// release the lock protecting socket state
1621	remote_queuelock_release( socket_lock_xp );
1622
1623	return;
1624
1625	} // end if attached socket
1626
1627	// 4. scan the list of listening sockets
1628	listening_match = false;
1629
1630	// get pointers on NIC_RX[0] chdev
1631	xptr_t rx0_chdev_xp = chdev_dir.nic_rx[0];
1632	chdev_t * rx0_chdev_ptr = GET_PTR( rx0_chdev_xp );
1633	cxy_t rx0_chdev_cxy = GET_CXY( rx0_chdev_xp );
1634
1635	// build extended pointers on list of listening sockets
1636	xptr_t rx0_root_xp = XPTR( rx0_chdev_cxy , &rx0_chdev_ptr->ext.nic.root );
1637	xptr_t rx0_lock_xp = XPTR( rx0_chdev_cxy , &rx0_chdev_ptr->ext.nic.lock );
1638
1639	// take the lock protecting the list of listening sockets
1640	remote_busylock_acquire( rx0_lock_xp );
1641
1642	// scan the xlist of listening socket
1643	XLIST_FOREACH( rx0_root_xp , iter_xp )
1644	{
1645	// get socket cluster and local pointer
1646	socket_xp = XLIST_ELEMENT( iter_xp , socket_t , rx_list );
1647	socket_ptr = GET_PTR( socket_xp );
1648	socket_cxy = GET_CXY( socket_xp );
1649
1650	// get relevant socket type and state
1651	socket_type = hal_remote_l32(XPTR(socket_cxy , &socket_ptr->type ));
1652	socket_state = hal_remote_l32(XPTR(socket_cxy , &socket_ptr->state ));
1653
1654	// check socket type and state
1655	assert( __FUNCTION__, (socket_type == SOCK_STREAM ) , "illegal socket type" );
1656	assert( __FUNCTION__, (socket_state == TCP_STATE_LISTEN ) , "illegal socket state" );
1657
1658	// get relevant socket infos for matching
1659	socket_local_addr = hal_remote_l32(XPTR(socket_cxy , &socket_ptr->local_addr ));
1660	socket_local_port = hal_remote_l32(XPTR(socket_cxy , &socket_ptr->local_port ));
1661
1662	// compute matching condition for a listening socket
1663	listening_match = (socket_local_addr == seg_local_addr) &&
1664	(socket_local_port == seg_local_port);
1665
1666	// exit loop if matching
1667	if( listening_match )
1668	{
1669
1670	#if DEBUG_DEV_NIC_RX \|\| DEBUG_DEV_NIC_ERROR
1671	fdid = hal_remote_l32( XPTR( socket_cxy , &socket_ptr->fdid ) );
1672	pid = hal_remote_l32( XPTR( socket_cxy , &socket_ptr->pid ) );
1673	#endif
1674
1675	#if DEBUG_DEV_NIC_RX
1676	if( DEBUG_DEV_NIC_RX < cycle )
1677	printk("\n[%s] matching listening socket[%d,%d] / state %s\n",
1678	__FUNCTION__, pid, fdid, socket_state_str(socket_state) );
1679	#endif
1680	break;
1681	}
1682	} // end loop on listening sockets
1683
1684	// release the lock protecting the list of listening sockets
1685	remote_busylock_release( rx0_lock_xp );
1686
1687	// 5. handle TCP segment for a matching listening socket
1688	if( listening_match )
1689	{
1690	// The actions depend on the received segment flags
1691	// - discard segment for RST or ACK,
1692	// - for SYN, register the connect request in listening socket CRQ queue,
1693	// and unblock the client thread in case of pending RX_ACCEPT command.
1694
1695	// [1] check RST
1696	if( seg_rst_set ) // discard segment
1697	{
1698
1699	#if DEBUG_DEV_NIC_ERROR
1700	printk("\n[ERROR] in %s : socket[%x,%d] %s / received RST => discard segment\n",
1701	__FUNCTION__, pid, fdid, socket_state_str(socket_state) );
1702	#endif
1703	return;
1704	}
1705
1706	// [2] check ACK
1707	if( seg_ack_set ) // send RST to remote
1708	{
1709
1710	#if DEBUG_DEV_NIC_ERROR
1711	printk("\n[ERROR] in %s : socket[%x,%d] %s received ACK => send RST & discard \n",
1712	__FUNCTION__, pid, fdid, socket_state_str(socket_state) );
1713	#endif
1714	// make an RST request to R2T queue
1715	socket_put_r2t_request( socket_r2tq_xp,
1716	TCP_FLAG_RST,
1717	chdev->channel );
1718	return;
1719	}
1720
1721	// [3] handle security & precedence TODO ... someday
1722
1723	// handle SYN == CONNECT request
1724	if( seg_syn_set )
1725	{
1726	// build extended pointers on various listening socket fields
1727	socket_lock_xp = XPTR( socket_cxy , &socket_ptr->lock );
1728	socket_crqq_xp = XPTR( socket_cxy , &socket_ptr->crqq );
1729	socket_r2tq_xp = XPTR( socket_cxy , &socket_ptr->r2tq );
1730
1731	// take the lock protecting the matching socket
1732	remote_queuelock_acquire( socket_lock_xp );
1733
1734	// try to register request into CRQ queue
1735	error = socket_put_crq_request( socket_crqq_xp,
1736	seg_remote_addr,
1737	seg_remote_port,
1738	seg_seq_num,
1739	seg_window );
1740	if ( error ) // CRQ full
1741	{
1742
1743	#if DEBUG_DEV_NIC_ERROR
1744	printk("\n[ERROR] in %s : listening socket[%x,%d] %s receive SYN but CRQ full => send RST\n",
1745	__FUNCTION__, pid, fdid );
1746	#endif
1747	// make an RST request to R2T queue
1748	socket_put_r2t_request( socket_r2tq_xp,
1749	TCP_FLAG_RST,
1750	chdev->channel );
1751	}
1752	else // register request in listening socket CRQ
1753	{
1754
1755	#if DEBUG_DEV_NIC_RX
1756	if( DEBUG_DEV_NIC_RX < cycle )
1757	if( cycle > DEBUG_DEV_NIC_RX )
1758	printk("\n[%s] listening socket[%x,%d] register request in CRQ\n",
1759	__FUNCTION__, pid, fdid );
1760	#endif
1761	bool_t rx_valid = hal_remote_l32( XPTR(socket_cxy , &socket_ptr->rx_valid));
1762	uint32_t rx_cmd = hal_remote_l32( XPTR(socket_cxy , &socket_ptr->rx_cmd));
1763
1764	// check pending ACCEPT command
1765	if( rx_valid && (rx_cmd == CMD_RX_ACCEPT) )
1766	{
1767	// reset rx_valid
1768	hal_remote_s32( XPTR( socket_cxy , &socket_ptr->rx_valid ), false );
1769
1770	// report success to RX client thread, that will
1771	// create a new socket and request a SYN-ACK to TX server thread
1772	dev_nic_unblock_rx_client( socket_xp , CMD_STS_SUCCESS );
1773
1774	#if DEBUG_DEV_NIC_RX
1775	if( DEBUG_DEV_NIC_RX < cycle )
1776	if( cycle > DEBUG_DEV_NIC_RX )
1777	printk("\n[%s] listening socket[%x,%d] unblock RX client thread\n",
1778	__FUNCTION__, fdid );
1779	#endif
1780	}
1781	} // end register request in CRQ
1782
1783	// release the lock protecting the matching socket
1784	remote_queuelock_release( socket_lock_xp );
1785
1786	} // end if SYN
1787
1788	return;
1789
1790	} // end if listening_match
1791
1792	// 6. no attached socket found and no listening socket found => discard segment
1793
1794	#if DEBUG_DEV_NIC_ERROR
1795	printk("\n[ERROR] in %s : thread[%x,%d] / unexpected TCP segment => discard / cycle %d\n",
1796	__FUNCTION__, this->process->pid, this->trdid, chdev->channel, cycle );
1797	#endif
1798
1799	} // end dev_nic_rx_handle_tcp_segment()
1800
1801
1802	/////////////////////////////////////////
1803	void dev_nic_rx_server( chdev_t * chdev )
1804	{
1805	uint8_t k_buf[2048]; // kernel buffer for one ETH/IP/UDP packet
1806	uint32_t pkt_src_addr; // packet source IP address
1807	uint32_t pkt_dst_addr; // packet destination IP address
1808	uint32_t trsp_protocol; // transport protocol (TCP / UDP)
1809	uint32_t eth_length; // size of Ethernet packet (bytes)
1810	uint32_t ip_length; // size of IP packet in bytes
1811	error_t error;
1812
1813	thread_t * this = CURRENT_THREAD;
1814
1815	// check thread can yield
1816	thread_assert_can_yield( this , __FUNCTION__ );
1817
1818	// check chdev direction and type
1819	assert( __FUNCTION__, (chdev->func == DEV_FUNC_NIC) && (chdev->is_rx == true) ,
1820	"illegal chdev type or direction" );
1821
1822	#if DEBUG_DEV_NIC_RX \|\| DEBUG_DEV_NIC_ERROR
1823	uint32_t cycle = (uint32_t)hal_get_cycles();
1824	#endif
1825
1826	#if DEBUG_DEV_NIC_RX
1827	if( cycle > DEBUG_DEV_NIC_RX )
1828	printk("\n[%s] thread[%x,%x] starts / cycle %d\n",
1829	__FUNCTION__, this->process->pid, this->trdid, cycle );
1830	#endif
1831
1832	// avoid warning
1833	ip_length = 0;
1834	error = 0;
1835
1836	// get extended pointers on server tread and chdev
1837	xptr_t thread_xp = XPTR( local_cxy , this );
1838	xptr_t chdev_xp = XPTR( local_cxy , chdev );
1839
1840	while( 1 )
1841	{
1842	// call NIC driver to move one packet from NIC_RX queue to kernel buffer
1843	this->nic_cmd.dev_xp = chdev_xp;
1844	this->nic_cmd.type = NIC_CMD_READ;
1845	this->nic_cmd.buffer = k_buf;
1846	chdev->cmd( XPTR( local_cxy , this ) );
1847
1848	// get packet length
1849	eth_length = this->nic_cmd.status;
1850
1851	// check success
1852	if( eth_length == 0 ) // queue empty => block and deschedule
1853	{
1854
1855	#if DEBUG_DEV_NIC_RX
1856	cycle = (uint32_t)hal_get_cycles();
1857	if( DEBUG_DEV_NIC_RX < cycle )
1858	printk("\n[%s] thread[%x,%x] NIC_RX_QUEUE empty => blocks on <ISR> / cycle %d\n",
1859	__FUNCTION__, this->process->pid, this->trdid, cycle );
1860	#endif
1861	// enable NIC_RX IRQ
1862	dev_pic_enable_irq( this->core->lid , chdev_xp );
1863
1864	// block and deschedule
1865	thread_block( thread_xp , THREAD_BLOCKED_ISR );
1866	sched_yield("client blocked on NIC_TX queue full");
1867
1868	// disable NIC-RX IRQ
1869	dev_pic_disable_irq( this->core->lid , chdev_xp );
1870
1871	#if DEBUG_DEV_NIC_RX
1872	cycle = (uint32_t)hal_get_cycles();
1873	if( DEBUG_DEV_NIC_RX < cycle )
1874	printk("\n[%s] thread[%x,%x] resumes / cycle %d\n",
1875	__FUNCTION__, this->process->pid, this->trdid, cycle );
1876	#endif
1877	// check possible error reported by NIC ISR
1878	if( this->nic_cmd.error )
1879	{
1880	printk("\n[PANIC] in %s : %s DMA engine cannot access RX_QUEUE / cycle %d\n",
1881	__FUNCTION__, chdev->name , (uint32_t)hal_get_cycles() );
1882	}
1883	}
1884	else // success => handle packet
1885	{
1886
1887	#if DEBUG_DEV_NIC_RX
1888	cycle = (uint32_t)hal_get_cycles();
1889	if( DEBUG_DEV_NIC_RX < cycle )
1890	#endif
1891
1892	// analyse the ETH header
1893	error = dev_nic_rx_check_eth( k_buf,
1894	&ip_length );
1895
1896	// discard packet if error reported by Ethernet layer
1897	if( error )
1898	{
1899
1900	#if DEBUG_DEV_NIC_ERROR
1901	printk("\n[WARNING] in %s : thread[%x,%x] discard ETH packet / cycle %d\n",
1902	__FUNCTION__, this->process->pid, this->trdid, cycle );
1903	#endif
1904	continue;
1905	}
1906
1907	#if (DEBUG_DEV_NIC_RX & 1)
1908	cycle = (uint32_t)hal_get_cycles();
1909	if( DEBUG_DEV_NIC_RX < cycle )
1910	printk("\n[%s] thread[%x,%x] successfully checked ETH packet / cycle %d\n",
1911	__FUNCTION__, this->process->pid, this->trdid, cycle );
1912	#endif
1913	// analyse the IP header
1914	error = dev_nic_rx_check_ip( k_buf + ETH_HEAD_LEN,
1915	ip_length,
1916	&pkt_src_addr,
1917	&pkt_dst_addr,
1918	&trsp_protocol );
1919
1920	// discard packet if error reported by IP layer
1921	if( error )
1922	{
1923
1924	#if DEBUG_DEV_NIC_ERROR
1925	printk("\n[WARNING] in %s : thread[%x,%x] discard IP packet / cycle %d\n",
1926	__FUNCTION__, this->process->pid, this->trdid, cycle );
1927	#endif
1928	continue;
1929	}
1930
1931	#if (DEBUG_DEV_NIC_RX & 1 )
1932	cycle = (uint32_t)hal_get_cycles();
1933	if( (DEBUG_DEV_NIC_RX < cycle) && (trsp_protocol == PROTOCOL_UDP) )
1934	printk("\n[%s] thread[%x,%x] successfully checked UDP packet / cycle %d\n",
1935	__FUNCTION__, this->process->pid, this->trdid, cycle );
1936	if( (DEBUG_DEV_NIC_RX < cycle) && (trsp_protocol == PROTOCOL_TCP) )
1937	printk("\n[%s] thread[%x,%x] successfully checked TCP segment / cycle %d\n",
1938	__FUNCTION__, this->process->pid, this->trdid, cycle );
1939	#endif
1940
1941	// call relevant transport protocol
1942	if( trsp_protocol == PROTOCOL_UDP )
1943	{
1944	dev_nic_rx_handle_udp_packet( chdev,
1945	k_buf + ETH_HEAD_LEN + IP_HEAD_LEN,
1946	ip_length - IP_HEAD_LEN,
1947	pkt_src_addr,
1948	pkt_dst_addr );
1949	}
1950	else if ( trsp_protocol == PROTOCOL_TCP)
1951	{
1952	dev_nic_rx_handle_tcp_segment( chdev,
1953	k_buf + ETH_HEAD_LEN + IP_HEAD_LEN,
1954	ip_length - IP_HEAD_LEN,
1955	pkt_src_addr,
1956	pkt_dst_addr );
1957	}
1958	else // discard packet if unsupported transport protocol
1959	{
1960
1961	#if DEBUG_DEV_NIC_ERROR
1962	cycle = (uint32_t)hal_get_cycles();
1963	if( DEBUG_DEV_NIC_RX < cycle )
1964	printk("\n[WARNING] in %s : thread[%x,%x] unsupported transport protocol %d / cycle %d\n",
1965	__FUNCTION__, this->process->pid, this->trdid, trsp_protocol, cycle );
1966	#endif
1967	continue;
1968	}
1969	} // end else success
1970	} // end of while loop
1971	} // end dev_nic_rx_server()
1972
1973
1974
1975
1976	///////////////////////////////////////////////////////////////////////////////////////////
1977	// Functions used by the NIC_TX server thread
1978	///////////////////////////////////////////////////////////////////////////////////////////
1979
1980	///////////////////////////////////////////////////////////////////////////////////////////
1981	// This static function is called by the dev_nic_tx_send_packet() function.
1982	// It moves one ETH/IP/UDP packet from the kernel buffer identified by the <buffer> and
1983	// <length> arguments to the NIC_TX_QUEUE identified the <chdev> argument.
1984	// It blocks and deschedules on the BLOCKED_ISR condition if the queue is full.
1985	///////////////////////////////////////////////////////////////////////////////////////////
1986	// @ chdev : [in] local pointer on NIC_TX chdev.
1987	// @ k_buf : [in] pointer on a local kernel buffer (2K bytes).
1988	// @ length : [in] actual Ethernet packet length in bytes.
1989	///////////////////////////////////////////////////////////////////////////////////////////
1990	static void dev_nic_tx_move_packet( chdev_t * chdev,
1991	uint8_t * k_buf,
1992	uint32_t length )
1993	{
1994	thread_t * this = CURRENT_THREAD;
1995
1996	// get extended pointers on server tread and chdev
1997	xptr_t thread_xp = XPTR( local_cxy , this );
1998	xptr_t chdev_xp = XPTR( local_cxy , chdev );
1999
2000	// check thread can yield
2001	thread_assert_can_yield( this , __FUNCTION__ );
2002
2003	#if (DEBUG_DEV_NIC_TX & 1)
2004	uint32_t cycle = (uint32_t)hal_get_cycles();
2005	if( DEBUG_DEV_NIC_TX < cycle )
2006	printk("\n[%s] thread[%x,%x] enter / buf %x / length %d / cycle %d\n",
2007	__FUNCTION__, this->process->pid, this->trdid, k_buf, length, cycle );
2008	#endif
2009
2010	// initialize WRITE command in server thread descriptor
2011	this->nic_cmd.dev_xp = chdev_xp;
2012	this->nic_cmd.type = NIC_CMD_WRITE;
2013	this->nic_cmd.buffer = k_buf;
2014	this->nic_cmd.length = length;
2015	this->nic_cmd.error = 0;
2016
2017	while( 1 )
2018	{
2019	// call driver to move TX packet
2020	chdev->cmd( thread_xp );
2021
2022	// exit while if success
2023	if( this->nic_cmd.status == length ) // exit while & return if success
2024	{
2025
2026	#if (DEBUG_DEV_NIC_TX & 1)
2027	cycle = (uint32_t)hal_get_cycles();
2028	if( DEBUG_DEV_NIC_TX < cycle )
2029	printk("\n[%s] thread[%x,%x] exit SUCCESS / cycle %d\n",
2030	__FUNCTION__, this->process->pid, this->trdid, cycle );
2031	#endif
2032	break;
2033	}
2034	else // block and deschedule if queue full
2035	{
2036
2037	#if (DEBUG_DEV_NIC_TX & 1)
2038	cycle = (uint32_t)hal_get_cycles();
2039	if( DEBUG_DEV_NIC_TX < cycle )
2040	printk("\n[%s] thread[%x,%x] NIC_TX_QUEUE full => blocks on ISR / cycle %d\n",
2041	__FUNCTION__, this->process->pid, this->trdid, cycle );
2042	#endif
2043	// enable NIC_TX IRQ
2044	dev_pic_enable_irq( this->core->lid , chdev_xp );
2045
2046	// TX server thread blocks and deschedules
2047	thread_block( thread_xp , THREAD_BLOCKED_ISR );
2048	sched_yield("client blocked on NIC_TX queue full");
2049
2050	// disable NIC-TX IRQ
2051	dev_pic_disable_irq( this->core->lid , chdev_xp );
2052
2053	#if (DEBUG_DEV_NIC_TX & 1)
2054	cycle = (uint32_t)hal_get_cycles();
2055	if( DEBUG_DEV_NIC_TX < cycle )
2056	printk("\n[%s] thread[%x,%x] resumes / cycle %d\n",
2057	__FUNCTION__, this->process->pid, this->trdid, cycle );
2058	#endif
2059	}
2060	}
2061	} // end dev_nic_tx_move_packet()
2062
2063	///////////////////////////////////////////////////////////////////////////////////////////
2064	// This static function is called by the dev_nic_tx_server() function to build an UDP
2065	// header in the kernel buffer defined by the <k_buf> arguement, as specified by the
2066	// <socket_xp> argument. The <length> argument defines the number of bytes in payload.
2067	// It set the "src_port", "dst_port", "total_length" and "checksum" fields in UDP header.
2068	// The payload must be previouly loaded in the kernel buffer.
2069	///////////////////////////////////////////////////////////////////////////////////////////
2070	// @ k_buf : [in] pointer on first byte of UDP header in kernel buffer.
2071	// @ socket_xp : [in] extended pointer on socket.
2072	// @ length : [in] number of bytes in payload.
2073	///////////////////////////////////////////////////////////////////////////////////////////
2074	static void dev_nic_tx_build_udp_header( uint8_t * k_buf,
2075	xptr_t socket_xp,
2076	uint32_t length )
2077	{
2078	uint16_t checksum; // checksum value
2079	uint32_t total_length; // total UDP packet length
2080	uint32_t local_addr; // local IP address
2081	uint32_t remote_addr; // remote IP address
2082	uint32_t local_port; // local port
2083	uint32_t remote_port; // remote port
2084
2085	// get socket cluster an local pointer
2086	socket_t * socket_ptr = GET_PTR( socket_xp );
2087	cxy_t socket_cxy = GET_CXY( socket_xp );
2088
2089	// get relevant infos from socket
2090	local_addr = hal_remote_l32(XPTR(socket_cxy , &socket_ptr->local_addr ));
2091	remote_addr = hal_remote_l32(XPTR(socket_cxy , &socket_ptr->remote_addr ));
2092	local_port = hal_remote_l32(XPTR(socket_cxy , &socket_ptr->local_port ));
2093	remote_port = hal_remote_l32(XPTR(socket_cxy , &socket_ptr->remote_port ));
2094
2095	// compute UDP packet total length
2096	total_length = length + UDP_HEAD_LEN;
2097
2098	// set src_port and dst_port in header
2099	k_buf[0] = local_port >> 8;
2100	k_buf[1] = local_port;
2101	k_buf[2] = remote_port >> 8;
2102	k_buf[3] = remote_port;
2103
2104	// reset checksum
2105	k_buf[6] = 0;
2106	k_buf[7] = 0;
2107
2108	// set packet length in header
2109	k_buf[4] = total_length >> 8;
2110	k_buf[5] = total_length;
2111
2112	// compute UDP packet checksum
2113	checksum = dev_nic_tcp_udp_checksum( k_buf,
2114	total_length,
2115	local_addr,
2116	remote_addr,
2117	false ); // is_not_tcp
2118	// set checksum
2119	k_buf[6] = checksum >> 8;
2120	k_buf[7] = checksum;
2121
2122	} // end dev_nic_tx_build_udp_header()
2123
2124	///////////////////////////////////////////////////////////////////////////////////////////
2125	// This static function is called by the dev_nic_tx_server() function.
2126	// It builds a TCP header in the kernel buffer defined by the <k_buf> argument.
2127	// The payload must have been previouly registered in this buffer (for checksum).
2128	// The "local_addr", "local_port", "remote_addr", "remote_port", seq_num", "ack_num",
2129	// and "window" fields are obtained from the <socket_xp> argument.
2130	// The <length> argument defines the number of bytes in payload, and the <flags> argument
2131	// defines the flags to be set in TCP header.
2132	///////////////////////////////////////////////////////////////////////////////////////////
2133	// @ k_buf : [in] pointer on first byte of TCP header in kernel buffer.
2134	// @ socket_xp : [in] extended pointer on socket.
2135	// @ length : [in] number of bytes in payload.
2136	// @ flags : [in] flags to be set in TCP header.
2137	///////////////////////////////////////////////////////////////////////////////////////////
2138	static void dev_nic_tx_build_tcp_header( uint8_t * k_buf,
2139	xptr_t socket_xp,
2140	uint32_t length,
2141	uint8_t flags )
2142	{
2143	uint16_t checksum; // global segment checksum
2144	uint32_t total_length; // total UDP packet length
2145	uint32_t src_addr; // local IP address
2146	uint32_t dst_addr; // remote IP address
2147	uint16_t src_port; // local port
2148	uint16_t dst_port; // remote port
2149	uint32_t seq_num; // first byte of segment in TX stream
2150	uint32_t ack_num; // next expected byte in RX stream
2151	uint32_t window; // window of accepted segments in RX stream
2152
2153	// get socket cluster an local pointer
2154	socket_t * sock_ptr = GET_PTR( socket_xp );
2155	cxy_t sock_cxy = GET_CXY( socket_xp );
2156
2157	// get relevant infos from socket
2158	src_addr = hal_remote_l32(XPTR( sock_cxy , &sock_ptr->local_addr ));
2159	dst_addr = hal_remote_l32(XPTR( sock_cxy , &sock_ptr->remote_addr ));
2160	src_port = hal_remote_l32(XPTR( sock_cxy , &sock_ptr->local_port ));
2161	dst_port = hal_remote_l32(XPTR( sock_cxy , &sock_ptr->remote_port ));
2162	seq_num = hal_remote_l32(XPTR( sock_cxy , &sock_ptr->tx_nxt ));
2163	ack_num = hal_remote_l32(XPTR( sock_cxy , &sock_ptr->rx_nxt ));
2164	window = hal_remote_l32(XPTR( sock_cxy , &sock_ptr->rx_wnd ));
2165
2166	// compute TCP segment total length
2167	total_length = length + TCP_HEAD_LEN;
2168
2169	// set "src_port" and "dst_port"
2170	k_buf[0] = src_port >> 8;
2171	k_buf[1] = src_port;
2172	k_buf[2] = dst_port >> 8;
2173	k_buf[3] = dst_port;
2174
2175	// set "seq_num"
2176	k_buf[4] = seq_num >> 24;
2177	k_buf[5] = seq_num >> 16;
2178	k_buf[6] = seq_num >> 8;
2179	k_buf[7] = seq_num;
2180
2181	// set "ack_num"
2182	k_buf[8] = ack_num >> 24;
2183	k_buf[9] = ack_num >> 16;
2184	k_buf[10] = ack_num >> 8;
2185	k_buf[11] = ack_num;
2186
2187	// set "hlen"
2188	k_buf[12] = 5;
2189
2190	// set "flags"
2191	k_buf[13] = flags & 0x3F;
2192
2193	// set "window"
2194	k_buf[14] = window >> 8;
2195	k_buf[15] = window;
2196
2197	// reset "checksum"
2198	k_buf[16] = 0;
2199	k_buf[17] = 0;
2200
2201	// set "urgent_ptr"
2202	k_buf[18] = 0;
2203	k_buf[19] = 0;
2204
2205	// compute TCP segment checksum
2206	checksum = dev_nic_tcp_udp_checksum( k_buf,
2207	total_length,
2208	src_addr,
2209	dst_addr,
2210	true ); // is_tcp
2211	// set "checksum"
2212	k_buf[16] = checksum >> 8;
2213	k_buf[17] = checksum;
2214
2215	} // end dev_nic_tx_build_tcp_header()
2216
2217
2218	///////////////////////////////////////////////////////////////////////////////////////////
2219	// This static function is called by the dev_nic_tx_server() function.
2220	// It builds the IP header in the 20 first bytes of <buffer>.
2221	///////////////////////////////////////////////////////////////////////////////////////////
2222	// @ buffer : pointer on first byte of IP header in kernel buffer
2223	// @ src_addr : source IP address.
2224	// @ dst_addr : destination IP address.
2225	// @ length : number of bytes in IP packet payload.
2226	///////////////////////////////////////////////////////////////////////////////////////////
2227	static void dev_nic_tx_build_ip_header( uint8_t * buffer,
2228	uint32_t src_addr,
2229	uint32_t dst_addr,
2230	uint8_t protocol,
2231	uint16_t length )
2232	{
2233	uint16_t hcs;
2234
2235	uint16_t total = length + IP_HEAD_LEN;
2236
2237	buffer[0] = 0x45; // IPV4 / IHL = 20 bytes
2238	buffer[1] = 0; // DSCP / ECN
2239	buffer[2] = total >> 8;
2240	buffer[3] = total;
2241
2242	buffer[4] = 0x40; // Don't Fragment
2243	buffer[5] = 0;
2244	buffer[6] = 0;
2245	buffer[7] = 0;
2246
2247	buffer[8] = 0xFF; // TTL
2248	buffer[9] = protocol; // transport protocol
2249
2250	buffer[12] = src_addr >> 24;
2251	buffer[13] = src_addr >> 16;
2252	buffer[14] = src_addr >> 8;
2253	buffer[15] = src_addr;
2254
2255	buffer[16] = dst_addr >> 24;
2256	buffer[17] = dst_addr >> 16;
2257	buffer[18] = dst_addr >> 8;
2258	buffer[19] = dst_addr;
2259
2260	// compute IP header checksum
2261	hcs = dev_nic_ip_checksum( buffer );
2262
2263	// set checksum
2264	buffer[10] = hcs >> 8;
2265	buffer[11] = hcs;
2266
2267	} // end dev_nic_tx_build_ip_header
2268
2269	///////////////////////////////////////////////////////////////////////////////////////////
2270	// This static function is called by the dev_nic_tx_server() function.
2271	// It builds the Ethernet header in the 14 first bytes of <buffer>.
2272	///////////////////////////////////////////////////////////////////////////////////////////
2273	// @ buffer : pointer on first byte of Ethernet header in kernel buffer
2274	// @ src_mac_54 : two MSB bytes in source MAC address.
2275	// @ src_mac_32 : two MED bytes in source MAC address.
2276	// @ src_mac_10 : two LSB bytes in source MAC address.
2277	// @ dst_mac_54 : two MSB bytes in destination MAC address.
2278	// @ dst_mac_32 : two MED bytes in destination MAC address.
2279	// @ dst_mac_10 : two LSB bytes in destination MAC address.
2280	// @ length : number of bytes in Ethernet frame payload.
2281	///////////////////////////////////////////////////////////////////////////////////////////
2282	static void dev_nic_tx_build_eth_header( uint8_t * buffer,
2283	uint8_t src_mac_5,
2284	uint8_t src_mac_4,
2285	uint8_t src_mac_3,
2286	uint8_t src_mac_2,
2287	uint8_t src_mac_1,
2288	uint8_t src_mac_0,
2289	uint8_t dst_mac_5,
2290	uint8_t dst_mac_4,
2291	uint8_t dst_mac_3,
2292	uint8_t dst_mac_2,
2293	uint8_t dst_mac_1,
2294	uint8_t dst_mac_0,
2295	uint32_t length )
2296	{
2297	buffer[0] = dst_mac_5;
2298	buffer[1] = dst_mac_4;
2299	buffer[2] = dst_mac_3;
2300	buffer[3] = dst_mac_2;
2301	buffer[4] = dst_mac_1;
2302	buffer[5] = dst_mac_0;
2303
2304	buffer[6] = src_mac_5;
2305	buffer[7] = src_mac_4;
2306	buffer[8] = src_mac_3;
2307	buffer[9] = src_mac_2;
2308	buffer[10] = src_mac_1;
2309	buffer[11] = src_mac_0;
2310
2311	buffer[12] = length >> 8;
2312	buffer[13] = length;
2313
2314	} // end dev_nic_tx_build_eth_header()
2315
2316
2317	///////////////////////////////////////////////////////////////////////////////////////////
2318	// This static function implement the TCP protocol as specified by the RFC.
2319	// It is called by the dev_nic_tx_server() function to handle one TX command,
2320	// or one R2T request, for the socket identified by the <socket_xp> argument.
2321	// It builds an ETH/IP/UDP packet or ETH/IP/TCP segment, in the 2 Kbytes kernel buffer,
2322	// defined by the <k_buf> argument from informations found in socket descriptor.
2323	// It returns a command status code (defined in the ksocket.h file), and returns in the
2324	// <total_length> argument the actual packet length.
2325	// It updates the "socket.state", "socket.tx_nxt", "socket.r2tq", "socket.crqq",
2326	// "socket.todo" fields as required by the command type, but it does NOT reset
2327	// the "socket.tx_valid" field and does NOT unblock the client thread.
2328	// It does NOt take the socket lock, that is taken by the dev_nic_server().
2329	///////////////////////////////////////////////////////////////////////////////////////////
2330	// To build a packet, it makes the following actions:
2331	// 1) it get the command arguments from socket descriptor.
2332	// 2) it build an UDP packet or a TCP segment, and update socket state.
2333	// 3) it build the IP header.
2334	// 4) it build the ETH header.
2335	///////////////////////////////////////////////////////////////////////////////////////////
2336	// @ socket_xp : [in] extended pointer on client socket.
2337	// @ k_buf : [in] local pointer on kernel buffer (2 Kbytes).
2338	// @ total_length : [out] total number of bytes written in k_buf.
2339	// @ return command status.
2340	///////////////////////////////////////////////////////////////////////////////////////////
2341	static socket_cmd_sts_t dev_nic_tx_build_packet( xptr_t socket_xp,
2342	uint8_t * k_buf,
2343	uint32_t * total_length )
2344	{
2345	socket_t * socket_ptr;
2346	cxy_t socket_cxy;
2347	xptr_t client_xp; // extended pointer on client thread
2348	bool_t cmd_valid; // valid user command
2349	bool_t r2t_valid; // valid R2T queue request
2350	uint32_t cmd_type; // NIC command type
2351	uint8_t * tx_buf; // local pointer on socket buffer for payload
2352	uint32_t len; // tx_buf length (bytes)
2353	uint32_t todo; // number of bytes not yet sent
2354	uint32_t socket_type; // socket type (UDP/TCP)
2355	uint32_t socket_state; // socket state
2356	xptr_t socket_r2tq_xp; // extended pointer on R2T queue
2357	uint32_t src_ip_addr; // source IP address
2358	uint32_t dst_ip_addr; // destination IP address
2359	uint32_t tx_nxt; // next sequence number in TX stream
2360	uint32_t nbytes; // number of bytes in UDP/TCP packet payload
2361	uint8_t * k_trsp_base; // pointer on UDP/TCP packet in kernel buffer
2362	uint32_t trsp_length; // length of TCP/UDP packet
2363	uint8_t trsp_protocol; // transport protocol type (UDP/TCP)
2364	uint8_t r2t_flags; // flags defined by one R2T queue request
2365
2366	// get socket cluster and local pointer
2367	socket_cxy = GET_CXY( socket_xp );
2368	socket_ptr = GET_PTR( socket_xp );
2369
2370	#if DEBUG_DEV_NIC_TX \|\| DEBUG_DEV_NIC_ERROR
2371	uint32_t cycle = (uint32_t)hal_get_cycles();
2372	uint32_t socket_fdid = hal_remote_l32( XPTR( socket_cxy , &socket_ptr->fdid ));
2373	uint32_t socket_pid = hal_remote_l32( XPTR( socket_cxy , &socket_ptr->pid ));
2374	#endif
2375
2376	// build extended pointer on socket r2t queue
2377	socket_r2tq_xp = XPTR( socket_cxy , &socket_ptr->r2tq );
2378
2379	// get cmd_valid & t2t_valid from socket descriptor
2380	cmd_valid = (bool_t)hal_remote_l32( XPTR( socket_cxy , &socket_ptr->tx_valid ));
2381	r2t_valid = (bool_t)remote_buf_status( XPTR( socket_cxy , &socket_ptr->r2tq ));
2382
2383	#if DEBUG_DEV_NIC_TX
2384	if( cycle > DEBUG_DEV_NIC_TX )
2385	printk("\n[%s] enter for socket[%x,%d] : cmd_val %d / r2t_val %d / cycle %d\n",
2386	__FUNCTION__, socket_pid, socket_fdid, cmd_valid, r2t_valid, cycle );
2387	#endif
2388
2389	// 1. get relevant socket infos
2390	socket_type = hal_remote_l32( XPTR( socket_cxy , &socket_ptr->type ));
2391	socket_state = hal_remote_l32( XPTR( socket_cxy , &socket_ptr->state ));
2392	src_ip_addr = hal_remote_l32( XPTR( socket_cxy , &socket_ptr->local_addr ));
2393	dst_ip_addr = hal_remote_l32( XPTR( socket_cxy , &socket_ptr->remote_addr ));
2394
2395	// compute UDP/TCP packet base in local kernel buffer
2396	k_trsp_base = k_buf + ETH_HEAD_LEN + IP_HEAD_LEN;
2397
2398	// default value
2399	trsp_length = 0;
2400
2401	if( cmd_valid ) // handle TX command depending on type
2402	{
2403	// get command arguments from socket
2404	cmd_type = hal_remote_l32( XPTR( socket_cxy , &socket_ptr->tx_cmd ));
2405	tx_buf = hal_remote_lpt( XPTR( socket_cxy , &socket_ptr->tx_buf ));
2406	len = hal_remote_l32( XPTR( socket_cxy , &socket_ptr->tx_len ));
2407	todo = hal_remote_l32( XPTR( socket_cxy , &socket_ptr->tx_todo ));
2408	client_xp = hal_remote_l64( XPTR( socket_cxy , &socket_ptr->tx_client ));
2409
2410	#if DEBUG_DEV_NIC_TX
2411	if( cycle > DEBUG_DEV_NIC_TX )
2412	printk("\n[%s] socket[%x,%d] / %s / command %s \n",
2413	__FUNCTION__, socket_pid, socket_fdid,
2414	socket_cmd_type_str(cmd_type),socket_state_str(socket_state) );
2415	#endif
2416
2417	//////////////////////////////////////////////////////////
2418	// 2. UDP : build UDP packet and update UDP socket state
2419	if( socket_type == SOCK_DGRAM )
2420	{
2421	trsp_protocol = PROTOCOL_UDP;
2422
2423	if( socket_state != UDP_STATE_ESTAB )
2424	{
2425	return CMD_STS_BADSTATE;
2426	}
2427	else if( cmd_type == CMD_TX_SEND )
2428	{
2429	// compute payload length
2430	nbytes = ( CONFIG_SOCK_PAYLOAD_MAX < todo ) ? CONFIG_SOCK_PAYLOAD_MAX : todo;
2431
2432	// move payload from remote socket tx_buf to local kernel buffer
2433	hal_remote_memcpy( XPTR( local_cxy , k_trsp_base + UDP_HEAD_LEN ),
2434	XPTR( socket_cxy , tx_buf + (len - todo) ),
2435	nbytes );
2436
2437	// build UDP header
2438	dev_nic_tx_build_udp_header( k_trsp_base,
2439	socket_xp,
2440	nbytes );
2441
2442	// update "tx_todo" in socket descriptor
2443	hal_remote_s32( XPTR(socket_cxy , &socket_ptr->tx_todo), todo - nbytes );
2444
2445	// set UDP packet length
2446	trsp_length = UDP_HEAD_LEN + nbytes;
2447
2448	#if DEBUG_DEV_NIC_TX
2449	if( cycle > DEBUG_DEV_NIC_TX )
2450	printk("\n[%s] socket[%x,%d] UDP packet build / %d bytes\n",
2451	__FUNCTION__, socket_pid, socket_fdid, nbytes );
2452	#endif
2453	}
2454	else // CONNECT, ACCEPT, or CLOSE commands are illegal for UDP
2455	{
2456
2457	#if DEBUG_DEV_NIC_ERROR
2458	printk("\n[ERROR] in %s : bad state %s for socket[%x,%x] / cycle %d\n",
2459	__FUNCTION__, socket_state_str(socket_state), socket_pid, socket_fdid, cycle );
2460	#endif
2461	return CMD_STS_BADCMD;
2462	}
2463	} // end UDP
2464
2465	///////////////////////////////////////////////////////////
2466	// 2. TCP : build TCP segment and update TCP socket state
2467	else if( socket_type == SOCK_STREAM )
2468	{
2469	trsp_protocol = PROTOCOL_TCP;
2470
2471	// handle R2T request / initialize r2t_flags
2472	if( r2t_valid )
2473	{
2474	// build extended pointers on r2t queue
2475	socket_r2tq_xp = XPTR( socket_cxy , &socket_ptr->r2tq );
2476
2477	// get one request from R2T queue, and update R2T queue
2478	socket_get_r2t_request( socket_r2tq_xp , &r2t_flags );
2479	}
2480	else
2481	{
2482	r2t_flags = 0;
2483	}
2484
2485	////////////////////////////////
2486	if( cmd_type == CMD_TX_CONNECT ) // always executed by a TCP client
2487	{
2488	if( (socket_state == TCP_STATE_BOUND) \|\|
2489	(socket_state == TCP_STATE_LISTEN) ) // send a SYN segment
2490	{
2491	// initialises socket tx_nxt, and rx_wnd
2492	hal_remote_s32(XPTR(socket_cxy , &socket_ptr->tx_nxt),
2493	CONFIG_SOCK_ISS_CLIENT );
2494	hal_remote_s32(XPTR(socket_cxy , &socket_ptr->rx_wnd),
2495	CONFIG_SOCK_MAX_WINDOW );
2496
2497	// build TCP SYN segment
2498	dev_nic_tx_build_tcp_header( k_trsp_base,
2499	socket_xp,
2500	0, // length
2501	TCP_FLAG_SYN );
2502	// set TCP packet length
2503	trsp_length = TCP_HEAD_LEN;
2504
2505	// update socket.state
2506	hal_remote_s32( XPTR( socket_cxy , &socket_ptr->state ),
2507	TCP_STATE_SYN_SENT );
2508
2509	// update socket.tx_nxt
2510	hal_remote_s32( XPTR( socket_cxy , &socket_ptr->tx_nxt ),
2511	CONFIG_SOCK_ISS_CLIENT + 1 );
2512	#if DEBUG_DEV_NIC_TX
2513	if( cycle > DEBUG_DEV_NIC_TX )
2514	printk("\n[%s] socket[%x,%d] %s / CONNECT / TCP SYN build\n",
2515	__FUNCTION__, socket_pid, socket_fdid, socket_state_str(socket_state) );
2516	#endif
2517	}
2518	else // report error for all other socket states
2519	{
2520
2521	#if DEBUG_DEV_NIC_ERROR
2522	printk("\n[ERROR] in %s : bad state %s socket[%x,%x] / cycle %d\n",
2523	__FUNCTION__, socket_state_str(socket_state), socket_pid, socket_fdid, cycle );
2524	#endif
2525	return CMD_STS_BADSTATE;
2526	}
2527	}
2528	////////////////////////////////////
2529	else if( cmd_type == CMD_TX_ACCEPT ) // always executed by a TCP server
2530	{
2531
2532	if( socket_state == TCP_STATE_SYN_RCVD ) // send a SYN-ACK segment
2533	{
2534	// initialize socket tx_nxt, and rx_wnd
2535	hal_remote_s32(XPTR(socket_cxy , &socket_ptr->tx_nxt),
2536	CONFIG_SOCK_ISS_SERVER );
2537	hal_remote_s32(XPTR(socket_cxy , &socket_ptr->rx_wnd),
2538	(1 << CONFIG_SOCK_RX_BUF_ORDER) );
2539
2540	// build TCP ACK-SYN segment
2541	dev_nic_tx_build_tcp_header( k_trsp_base,
2542	socket_xp,
2543	0, // length
2544	TCP_FLAG_SYN \| TCP_FLAG_ACK );
2545	// set TCP packet length
2546	trsp_length = TCP_HEAD_LEN;
2547
2548	// update socket.state
2549	hal_remote_s32( XPTR( socket_cxy , &socket_ptr->state ),
2550	TCP_STATE_SYN_RCVD );
2551
2552	// update socket.tx_nxt
2553	hal_remote_s32( XPTR( socket_cxy , &socket_ptr->tx_nxt ),
2554	CONFIG_SOCK_ISS_SERVER + 1 );
2555	#if DEBUG_DEV_NIC_TX
2556	if( cycle > DEBUG_DEV_NIC_TX )
2557	printk("\n[%s] socket[%x,%d] %s / ACCEPT / SYN-ACK build\n",
2558	__FUNCTION__, socket_pid, socket_fdid, socket_state_str(socket_state) );
2559	#endif
2560	}
2561	else // report error in all other socket states
2562	{
2563
2564	#if DEBUG_DEV_NIC_ERROR
2565	printk("\n[ERROR] in %s : bad state %s for socket[%x,%x] / cycle %d\n",
2566	__FUNCTION__, socket_state_str(socket_state), socket_pid, socket_fdid, cycle );
2567	#endif
2568	return CMD_STS_BADSTATE;
2569	}
2570	}
2571	///////////////////////////////////
2572	else if( cmd_type == CMD_TX_CLOSE )
2573	{
2574	if( (socket_state == TCP_STATE_SYN_RCVD ) \|\|
2575	(socket_state == TCP_STATE_ESTAB ) \|\|
2576	(socket_state == TCP_STATE_CLOSE_WAIT) ) // send a FIN-ACK segment
2577	{
2578	// get "tx_nxt" from socket descriptor
2579	tx_nxt = hal_remote_l32( XPTR(socket_cxy , &socket_ptr->tx_nxt ));
2580
2581	// compute next state
2582	uint32_t state = (socket_state == TCP_STATE_CLOSE_WAIT) ?
2583	TCP_STATE_LAST_ACK : TCP_STATE_FIN_WAIT1;
2584
2585	// update socket state
2586	hal_remote_s32( XPTR( socket_cxy , &socket_ptr->state ), state );
2587
2588	// build TCP FIN segment
2589	dev_nic_tx_build_tcp_header( k_trsp_base,
2590	socket_xp,
2591	0, // length
2592	TCP_FLAG_FIN \| TCP_FLAG_ACK );
2593
2594	// update "tx_nxt" in socket descriptor
2595	hal_remote_s32( XPTR(socket_cxy , &socket_ptr->tx_nxt), tx_nxt + 1 );
2596
2597	// set TCP packet length
2598	trsp_length = TCP_HEAD_LEN;
2599
2600	#if DEBUG_DEV_NIC_TX
2601	if( cycle > DEBUG_DEV_NIC_TX )
2602	printk("\n[%s] socket[%x,%d] %s / CLOSE / FIN-ACK build\n",
2603	__FUNCTION__, socket_pid, socket_fdid, socket_state_str(socket_state) );
2604	#endif
2605	}
2606	else // all other states => signal error
2607	{
2608
2609	#if DEBUG_DEV_NIC_ERROR
2610	printk("\n[ERROR] in %s : bad state %s for socket[%x,%x] / cycle %d\n",
2611	__FUNCTION__, socket_state_str(socket_state), socket_pid, socket_fdid, cycle );
2612	#endif
2613	return CMD_STS_BADSTATE;
2614	}
2615	}
2616	//////////////////////////////////
2617	else if( cmd_type == CMD_TX_SEND )
2618	{
2619	if( (socket_state == TCP_STATE_ESTAB ) \|\|
2620	(socket_state == TCP_STATE_CLOSE_WAIT) )
2621	{
2622	// get "tx_nxt" from socket descriptor
2623	tx_nxt = hal_remote_l32( XPTR(socket_cxy , &socket_ptr->tx_nxt ));
2624
2625	// compute actual payload length
2626	nbytes = ( CONFIG_SOCK_PAYLOAD_MAX < todo ) ?
2627	CONFIG_SOCK_PAYLOAD_MAX : todo;
2628
2629	// move payload from remote tx_buf to local kernel buffer
2630	hal_remote_memcpy( XPTR( local_cxy , k_trsp_base + TCP_HEAD_LEN ),
2631	XPTR( socket_cxy , tx_buf + (len - todo) ),
2632	nbytes );
2633
2634	// build TCP header
2635	dev_nic_tx_build_tcp_header( k_trsp_base,
2636	socket_xp,
2637	nbytes, // payload
2638	TCP_FLAG_ACK \| r2t_flags ); // flags
2639
2640	// update "tx_todo" in socket descriptor
2641	hal_remote_s32( XPTR(socket_cxy , &socket_ptr->tx_todo), todo - nbytes );
2642
2643	// update "tx_nxt" in socket descriptor
2644	hal_remote_s32( XPTR(socket_cxy , &socket_ptr->tx_nxt), tx_nxt + nbytes );
2645
2646	// set TCP packet length
2647	trsp_length = TCP_HEAD_LEN + nbytes;
2648
2649	#if DEBUG_DEV_NIC_TX
2650	if( cycle > DEBUG_DEV_NIC_TX )
2651	printk("\n[%s] socket[%x,%d] %s / SEND / %d bytes\n",
2652	__FUNCTION__, socket_pid, socket_fdid, socket_state_str(socket_state), nbytes );
2653	#endif
2654	}
2655	else // all other socket states
2656	{
2657
2658	#if DEBUG_DEV_NIC_ERROR
2659	printk("\n[ERROR] in %s : bad state %s for socket[%x,%x] / cycle %d\n",
2660	__FUNCTION__, socket_state_str(socket_state), socket_pid, socket_fdid, cycle );
2661	#endif
2662	return CMD_STS_BADSTATE;
2663	}
2664	}
2665	///////////////////////////////////
2666	else // undefined TX command type
2667	{
2668
2669	#if DEBUG_DEV_NIC_ERROR
2670	printk("\n[ERROR] in %s : undefined command type for socket[%x,%x] %s / cycle %d\n",
2671	__FUNCTION__, socket_pid, socket_fdid, socket_state_str(socket_state), cycle );
2672	#endif
2673	return CMD_STS_BADCMD;
2674	}
2675	} // end TCP
2676	}
2677	else // no valid TX command => handle R2T request only
2678	{
2679
2680	assert( __FUNCTION__ , (socket_type == SOCK_STREAM) , "don't use R2T queue for UDP" );
2681
2682	// get one request from R2T queue
2683	socket_get_r2t_request( socket_r2tq_xp , &r2t_flags );
2684
2685	#if DEBUG_DEV_NIC_TX
2686	cycle = (uint32_t)hal_get_cycles();
2687	if( cycle > DEBUG_DEV_NIC_TX )
2688	printk("\n[%s] socket[%x,%d] %s / send only flags %x / no data\n",
2689	__FUNCTION__, socket_pid, socket_fdid, socket_state_str(socket_state), r2t_flags );
2690	#endif
2691	// build TCP header
2692	dev_nic_tx_build_tcp_header( k_trsp_base,
2693	socket_xp,
2694	0, // no payload
2695	r2t_flags ); // flags
2696	// set protocol
2697	trsp_protocol = PROTOCOL_TCP;
2698
2699	// set TCP packet length
2700	trsp_length = TCP_HEAD_LEN;
2701	}
2702
2703	// 3. build IP header
2704	dev_nic_tx_build_ip_header( k_buf + ETH_HEAD_LEN,
2705	src_ip_addr,
2706	dst_ip_addr,
2707	trsp_protocol,
2708	trsp_length );
2709
2710	// 4. build ETH header
2711	dev_nic_tx_build_eth_header( k_buf,
2712	(uint8_t)DST_MAC_5,
2713	(uint8_t)DST_MAC_4,
2714	(uint8_t)DST_MAC_3,
2715	(uint8_t)DST_MAC_2,
2716	(uint8_t)DST_MAC_1,
2717	(uint8_t)DST_MAC_0,
2718	(uint8_t)SRC_MAC_5,
2719	(uint8_t)SRC_MAC_4,
2720	(uint8_t)SRC_MAC_3,
2721	(uint8_t)SRC_MAC_2,
2722	(uint8_t)SRC_MAC_1,
2723	(uint8_t)SRC_MAC_0,
2724	IP_HEAD_LEN + trsp_length );
2725
2726	#if DEBUG_DEV_NIC_TX
2727	cycle = (uint32_t)hal_get_cycles();
2728	if( cycle > DEBUG_DEV_NIC_TX )
2729	printk("\n[%s] exit for socket[%x,%d] / packet build / cycle %d\n",
2730	__FUNCTION__, socket_pid, socket_fdid, cycle );
2731	#endif
2732
2733	// return success and total packet length
2734	*total_length = ETH_HEAD_LEN + IP_HEAD_LEN + trsp_length;
2735	return CMD_STS_SUCCESS;
2736
2737	} // end dev_nic_tx_build_packet()
2738
2739	/////////////////////////////////////////
2740	void dev_nic_tx_server( chdev_t * chdev )
2741	{
2742	uint8_t k_buf[CONFIG_SOCK_PKT_BUF_SIZE]; // buffer for one packet
2743
2744	xptr_t queue_lock_xp; // extended pointer on lock for sockets list
2745	xptr_t root_xp; // extended pointer on sockets list root
2746	xptr_t iter_xp; // iterator for loop on sockets list
2747	xptr_t list_xp; // extended pointer on socket tx_list field
2748	xptr_t socket_xp; // extended pointer on found socket
2749	socket_t * socket_ptr; // local pointer on found socket
2750	cxy_t socket_cxy; // found socket cluster identifier
2751	xptr_t socket_lock_xp; // extented pointer on found socket lock
2752	bool_t cmd_valid; // TX command valid in socket descriptor
2753	bool_t r2t_valid; // valid R2T request in socket descriptor
2754	uint32_t sock_type; // socket type
2755	socket_cmd_sts_t cmd_sts; // value returned by dev_nic_tx_build_packet()
2756	socket_cmd_type_t tx_cmd; // socket TX command type
2757	uint32_t tx_todo; // socket number of bytes not sent yet
2758	uint32_t total_length; // length of the ETH/IP/TCP packet (bytes)
2759	bool_t found; // one active socket found
2760
2761	thread_t * this = CURRENT_THREAD;
2762
2763	#if DEBUG_DEV_NIC_TX
2764	uint32_t cycle = (uint32_t)hal_get_cycles();
2765	uint32_t pid;
2766	uint32_t fdid;
2767	if( cycle > DEBUG_DEV_NIC_TX )
2768	printk("\n[%s] thread[%x,%x] starts / cycle %d\n",
2769	__FUNCTION__, this->process->pid, this->trdid, cycle );
2770	#endif
2771
2772	// check chdev direction and type
2773	assert( __FUNCTION__, (chdev->func == DEV_FUNC_NIC) && (chdev->is_rx == false) ,
2774	"illegal chdev type or direction" );
2775
2776	// build extended pointers on client sockets queue lock
2777	queue_lock_xp = XPTR( local_cxy , &chdev->wait_lock );
2778
2779	// build extended pointers on client sockets queue root and first item
2780	root_xp = XPTR( local_cxy , &chdev->wait_root );
2781
2782	while( 1 ) // TX server infinite loop
2783	{
2784	// take the lock protecting the client sockets queue
2785	remote_busylock_acquire( queue_lock_xp );
2786
2787	found = false;
2788
2789	// scan registered sockets to find one active socket
2790	// with a round robin priority between the registered sockets
2791	if( xlist_is_empty( root_xp ) == false )
2792	{
2793	XLIST_FOREACH( root_xp , iter_xp )
2794	{
2795	// get client socket cluster and pointers
2796	socket_xp = XLIST_ELEMENT( iter_xp , socket_t , tx_list );
2797	socket_ptr = GET_PTR( socket_xp );
2798	socket_cxy = GET_CXY( socket_xp );
2799
2800	// build extended pointer on socket tx_list field
2801	list_xp = XPTR( socket_cxy , &socket_ptr->tx_list );
2802
2803	// get cmd_valid & r2t_valid from socket descriptor
2804	cmd_valid = (bool_t)hal_remote_l32( XPTR( socket_cxy , &socket_ptr->tx_valid ));
2805
2806	// get r2t_valid from socket descriptor
2807	r2t_valid = (bool_t)remote_buf_status( XPTR( socket_cxy , &socket_ptr->r2tq ));
2808
2809	if( cmd_valid \|\| r2t_valid ) // active => move socket, and exit loop
2810	{
2811	// move selected socket to last position for round-robin
2812	xlist_unlink( list_xp );
2813	xlist_add_last( root_xp , list_xp );
2814
2815	// exit loop
2816	found = true;
2817	break;
2818	}
2819	} // end loop on sockets
2820	}
2821
2822	// release the lock protecting the client sockets queue
2823	remote_busylock_release( queue_lock_xp );
2824
2825	if( found == false ) // block & deschedule if no active socket
2826	{
2827
2828	#if DEBUG_DEV_NIC_TX
2829	cycle = (uint32_t)hal_get_cycles();
2830	if( cycle > DEBUG_DEV_NIC_TX )
2831	printk("\n[%s] thread[%x,%x] no active socket => blocks on <CLIENT> / cycle %d\n",
2832	__FUNCTION__, this->process->pid, this->trdid, cycle );
2833	#endif
2834	// block and deschedule
2835	thread_block( XPTR( local_cxy , this ) , THREAD_BLOCKED_CLIENT );
2836	sched_yield( "waiting client" );
2837
2838	#if DEBUG_DEV_NIC_TX
2839	cycle = (uint32_t)hal_get_cycles();
2840	if( cycle > DEBUG_DEV_NIC_TX )
2841	printk("\n[%s] thread[%x,%x] resumes / cycle %d\n",
2842	__FUNCTION__, this->process->pid, this->trdid, cycle );
2843	#endif
2844	}
2845	else // handle active socket request
2846	{
2847	// avoid warning
2848	total_length = 0;
2849
2850	// build extended pointer on socket lock
2851	socket_lock_xp = XPTR( socket_cxy , &socket_ptr->lock );
2852
2853	// take socket lock
2854	remote_queuelock_acquire( socket_lock_xp );
2855
2856	#if DEBUG_DEV_NIC_TX
2857	cycle = (uint32_t)hal_get_cycles();
2858	pid = hal_remote_l32( XPTR( socket_cxy , &socket_ptr->pid ));
2859	fdid = hal_remote_l32( XPTR( socket_cxy , &socket_ptr->fdid ));
2860	#endif
2861
2862	#if DEBUG_DEV_NIC_TX
2863	if( cycle > DEBUG_DEV_NIC_TX )
2864	printk("\n[%s] thread[%x,%x] select socket[%x,%d] / cmd_val %d / r2t_val %d / cycle %d\n",
2865	__FUNCTION__, this->process->pid, this->trdid, pid, fdid, cmd_valid, r2t_valid, cycle );
2866	#endif
2867	// build one UDP packet / TCP segment
2868	cmd_sts = dev_nic_tx_build_packet( socket_xp,
2869	k_buf,
2870	&total_length );
2871	#if DEBUG_DEV_NIC_TX
2872	cycle = (uint32_t)hal_get_cycles();
2873	if( cycle > DEBUG_DEV_NIC_TX )
2874	printk("\n[%s] thread[%x,%x] for socket[%x,%x] build packet / %d bytes / sts %d / cycle %d\n",
2875	__FUNCTION__, this->process->pid, this->trdid, pid, fdid, total_length, cmd_sts, cycle );
2876	#endif
2877	// release socket lock
2878	remote_queuelock_release( socket_lock_xp );
2879
2880	if( cmd_sts == CMD_STS_SUCCESS ) // move packet to TX queue
2881	{
2882	// move packet to NIC_TX queue
2883	dev_nic_tx_move_packet( chdev,
2884	k_buf,
2885	total_length );
2886	#if DEBUG_DEV_NIC_TX
2887	cycle = (uint32_t)hal_get_cycles();
2888	if( cycle > DEBUG_DEV_NIC_TX )
2889	dev_nic_packet_display( pid, fdid, cycle, k_buf );
2890	#endif
2891	// get socket.type, socket.tx_cmd and socket.tx_todo values
2892	tx_cmd = hal_remote_l32( XPTR( socket_cxy , &socket_ptr->tx_cmd ));
2893	tx_todo = hal_remote_l32( XPTR( socket_cxy , &socket_ptr->tx_todo ));
2894	sock_type = hal_remote_l32( XPTR( socket_cxy , &socket_ptr->type ));
2895
2896	// client signaling depends on command type and socket type
2897	if( (tx_cmd == CMD_TX_SEND) && (tx_todo == 0) )
2898	{
2899	// reset tx_valid for both UDP and TCP
2900	hal_remote_s32( XPTR( socket_cxy , &socket_ptr->tx_valid), false );
2901
2902	// unblock client thread for UDP only
2903	if(sock_type == SOCK_DGRAM)
2904	dev_nic_unblock_tx_client( socket_xp , CMD_STS_SUCCESS );
2905	}
2906	else // type is CONNECT / ACCEPT / CLOSE
2907	{
2908	// reset tx_valid
2909	hal_remote_s32( XPTR( socket_cxy , &socket_ptr->tx_valid), false );
2910	}
2911	}
2912	else // signal error to client thread
2913	{
2914	// reset tx_valid
2915	hal_remote_s32( XPTR( socket_cxy , &socket_ptr->tx_valid), false );
2916
2917	// unblock tx_client thread
2918	dev_nic_unblock_tx_client( socket_xp , cmd_sts );
2919	}
2920	} // end active socket handling
2921	} // end infinite while loop
2922	} // end dev_nic_tx_server()
2923
2924
2925
2926
2927
2928	//////////////////////////////////////////////////
2929	void dev_nic_packet_display( pid_t socket_pid,
2930	uint32_t socket_fdid,
2931	uint32_t cycle,
2932	uint8_t * buf )
2933	{
2934	// get ETH header fields
2935	uint64_t eth_dst_mac = ((uint64_t)buf[5] << 40) \|
2936	((uint64_t)buf[4] << 32) \|
2937	((uint64_t)buf[3] << 24) \|
2938	((uint64_t)buf[2] << 16) \|
2939	((uint64_t)buf[1] << 8) \|
2940	((uint64_t)buf[0] ) ;
2941
2942	uint64_t eth_src_mac = ((uint64_t)buf[11] << 40) \|
2943	((uint64_t)buf[10] << 32) \|
2944	((uint64_t)buf[9] << 24) \|
2945	((uint64_t)buf[8] << 16) \|
2946	((uint64_t)buf[7] << 8) \|
2947	((uint64_t)buf[6] ) ;
2948
2949	uint16_t eth_length = ((uint16_t)buf[12] << 8) \|
2950	((uint16_t)buf[13] ) ;
2951
2952	// get IP header fields
2953	uint8_t ip_version = buf[14];
2954	uint8_t ip_tos = buf[15];
2955	uint16_t ip_length = ((uint16_t)buf[16] << 8) \|
2956	((uint16_t)buf[17] ) ;
2957
2958	uint16_t ip_ident = ((uint16_t)buf[18] << 8) \|
2959	((uint16_t)buf[19] ) ;
2960	uint16_t ip_offset = ((uint16_t)buf[20] << 8) \|
2961	((uint16_t)buf[21] ) ;
2962
2963	uint8_t ip_ttl = buf[22];
2964	uint8_t ip_protocol = buf[23];
2965	uint16_t ip_checksum = ((uint16_t)buf[24] << 8) \|
2966	((uint16_t)buf[25] ) ;
2967
2968	uint32_t ip_src_addr = ((uint32_t)buf[26] << 24) \|
2969	((uint32_t)buf[27] << 16) \|
2970	((uint32_t)buf[28] << 8) \|
2971	((uint32_t)buf[29] ) ;
2972
2973	uint32_t ip_dst_addr = ((uint32_t)buf[30] << 24) \|
2974	((uint32_t)buf[31] << 16) \|
2975	((uint32_t)buf[32] << 8) \|
2976	((uint32_t)buf[33] ) ;
2977
2978	// get pointers on TXT0 chdev
2979	xptr_t txt0_xp = chdev_dir.txt_tx[0];
2980	cxy_t txt0_cxy = GET_CXY( txt0_xp );
2981	chdev_t * txt0_ptr = GET_PTR( txt0_xp );
2982
2983	// get extended pointer on remote TXT0 chdev lock
2984	xptr_t lock_xp = XPTR( txt0_cxy , &txt0_ptr->wait_lock );
2985
2986	// get TXT0 lock
2987	remote_busylock_acquire( lock_xp );
2988
2989	nolock_printk("\n***** packet sent by NIC_TX server for socket[%x,%d] / cycle %d\n",
2990	socket_pid, socket_fdid, cycle );
2991
2992	nolock_printk(" ETH header\n");
2993	nolock_printk(" - dst_mac [6] = %l\n" , eth_dst_mac );
2994	nolock_printk(" - src_mac [6] = %l\n" , eth_src_mac );
2995	nolock_printk(" - length [2] = %d\n" , (uint32_t)eth_length );
2996	nolock_printk(" IP header\n");
2997	nolock_printk(" - version [1] = %x\n" , (uint32_t)ip_version );
2998	nolock_printk(" - tos [1] = %x\n" , (uint32_t)ip_tos );
2999	nolock_printk(" - length [2] = %d\n" , (uint32_t)ip_length );
3000	nolock_printk(" - ident [2] = %x\n" , (uint32_t)ip_ident );
3001	nolock_printk(" - offset [2] = %x\n" , (uint32_t)ip_offset );
3002	nolock_printk(" - ttl [1] = %x\n" , (uint32_t)ip_ttl );
3003	nolock_printk(" - protocol [1] = %x\n" , (uint32_t)ip_protocol );
3004	nolock_printk(" - checksum [2] = %x\n" , (uint32_t)ip_checksum );
3005	nolock_printk(" - src_addr [4] = %x\n" , (uint32_t)ip_src_addr );
3006	nolock_printk(" - dst_addr [4] = %x\n" , (uint32_t)ip_dst_addr );
3007
3008	// get UDP / TCP fields
3009	if ( ip_protocol == PROTOCOL_UDP )
3010	{
3011	uint16_t udp_src_port = ((uint16_t)buf[34] << 8) \|
3012	((uint16_t)buf[35] ) ;
3013	uint16_t udp_dst_port = ((uint16_t)buf[36] << 8) \|
3014	((uint16_t)buf[37] ) ;
3015
3016	nolock_printk(" UDP header\n");
3017	nolock_printk(" - src_port [2] = %d\n" , (uint32_t)udp_src_port );
3018	nolock_printk(" - dst_port [2] = %d\n" , (uint32_t)udp_dst_port );
3019	}
3020	else if( ip_protocol == PROTOCOL_TCP )
3021	{
3022	uint16_t tcp_src_port = ((uint16_t)buf[34] << 8) \|
3023	((uint16_t)buf[35] ) ;
3024	uint16_t tcp_dst_port = ((uint16_t)buf[36] << 8) \|
3025	((uint16_t)buf[37] ) ;
3026
3027	uint32_t tcp_seq_num = ((uint32_t)buf[38] << 24) \|
3028	((uint32_t)buf[39] << 16) \|
3029	((uint32_t)buf[40] << 8) \|
3030	((uint32_t)buf[41] ) ;
3031
3032	uint32_t tcp_ack_num = ((uint32_t)buf[42] << 24) \|
3033	((uint32_t)buf[43] << 16) \|
3034	((uint32_t)buf[44] << 8) \|
3035	((uint32_t)buf[45] ) ;
3036
3037	uint8_t tcp_hlen = buf[46];
3038	uint8_t tcp_flags = buf[47];
3039	uint16_t tcp_window = ((uint16_t)buf[48] << 8) \|
3040	((uint16_t)buf[49] ) ;
3041
3042	uint16_t tcp_checksum = ((uint16_t)buf[50] << 8) \|
3043	((uint16_t)buf[51] ) ;
3044	uint16_t tcp_urgent = ((uint16_t)buf[52] << 8) \|
3045	((uint16_t)buf[53] ) ;
3046
3047	nolock_printk(" TCP header\n");
3048	nolock_printk(" - src_port [2] = %x\n" , (uint32_t)tcp_src_port );
3049	nolock_printk(" - dst_port [2] = %x\n" , (uint32_t)tcp_dst_port );
3050	nolock_printk(" - seq_num [4] = %x\n" , (uint32_t)tcp_seq_num );
3051	nolock_printk(" - ack_num [4] = %x\n" , (uint32_t)tcp_ack_num );
3052	nolock_printk(" - hlen [1] = %d\n" , (uint32_t)tcp_hlen );
3053	nolock_printk(" - flags [1] = %x\n" , (uint32_t)tcp_flags );
3054	nolock_printk(" - window [2] = %x\n" , (uint32_t)tcp_window );
3055	nolock_printk(" - checksum [2] = %x\n" , (uint32_t)tcp_checksum );
3056	nolock_printk(" - urgent [2] = %x\n" , (uint32_t)tcp_urgent );
3057	}
3058	else
3059	{
3060	nolock_printk("!!!!! undefined transport protocol !!!!!\n");
3061	}
3062
3063	// release TXT0 lock
3064	remote_busylock_release( lock_xp );
3065
3066	} // end dev_nic_packet_display()
3067

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source: trunk/kernel/devices/dev_nic.c @ 690

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