blob: 44d750d98bc8ca4e7b67ace83785c4006d95816e [file] [log] [blame]
Dean Nelsona2d974d2005-03-23 20:50:00 -07001/*
2 * This file is subject to the terms and conditions of the GNU General Public
3 * License. See the file "COPYING" in the main directory of this archive
4 * for more details.
5 *
Dean Nelson714c48f2009-02-03 15:16:17 -08006 * Copyright (C) 1999-2009 Silicon Graphics, Inc. All rights reserved.
Dean Nelsona2d974d2005-03-23 20:50:00 -07007 */
8
Dean Nelsona2d974d2005-03-23 20:50:00 -07009/*
10 * Cross Partition Network Interface (XPNET) support
11 *
12 * XPNET provides a virtual network layered on top of the Cross
13 * Partition communication layer.
14 *
15 * XPNET provides direct point-to-point and broadcast-like support
16 * for an ethernet-like device. The ethernet broadcast medium is
17 * replaced with a point-to-point message structure which passes
18 * pointers to a DMA-capable block that a remote partition should
19 * retrieve and pass to the upper level networking layer.
20 *
21 */
22
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090023#include <linux/slab.h>
Dean Nelsona2d974d2005-03-23 20:50:00 -070024#include <linux/module.h>
Dean Nelsona2d974d2005-03-23 20:50:00 -070025#include <linux/netdevice.h>
26#include <linux/etherdevice.h>
Dean Nelson45d9ca42008-04-22 14:46:56 -050027#include "xp.h"
Dean Nelsona2d974d2005-03-23 20:50:00 -070028
Dean Nelsona2d974d2005-03-23 20:50:00 -070029/*
30 * The message payload transferred by XPC.
31 *
32 * buf_pa is the physical address where the DMA should pull from.
33 *
34 * NOTE: for performance reasons, buf_pa should _ALWAYS_ begin on a
35 * cacheline boundary. To accomplish this, we record the number of
36 * bytes from the beginning of the first cacheline to the first useful
37 * byte of the skb (leadin_ignore) and the number of bytes from the
38 * last useful byte of the skb to the end of the last cacheline
39 * (tailout_ignore).
40 *
41 * size is the number of bytes to transfer which includes the skb->len
42 * (useful bytes of the senders skb) plus the leadin and tailout
43 */
44struct xpnet_message {
45 u16 version; /* Version for this message */
46 u16 embedded_bytes; /* #of bytes embedded in XPC message */
47 u32 magic; /* Special number indicating this is xpnet */
Dean Nelsona812dcc2008-07-29 22:34:16 -070048 unsigned long buf_pa; /* phys address of buffer to retrieve */
Dean Nelsona2d974d2005-03-23 20:50:00 -070049 u32 size; /* #of bytes in buffer */
50 u8 leadin_ignore; /* #of bytes to ignore at the beginning */
51 u8 tailout_ignore; /* #of bytes to ignore at the end */
52 unsigned char data; /* body of small packets */
53};
54
55/*
56 * Determine the size of our message, the cacheline aligned size,
57 * and then the number of message will request from XPC.
58 *
59 * XPC expects each message to exist in an individual cacheline.
60 */
Dean Nelsonbd3e64c2008-07-29 22:34:19 -070061#define XPNET_MSG_SIZE XPC_MSG_PAYLOAD_MAX_SIZE
Dean Nelsona2d974d2005-03-23 20:50:00 -070062#define XPNET_MSG_DATA_MAX \
Dean Nelsonbd3e64c2008-07-29 22:34:19 -070063 (XPNET_MSG_SIZE - offsetof(struct xpnet_message, data))
64#define XPNET_MSG_NENTRIES (PAGE_SIZE / XPC_MSG_MAX_SIZE)
Dean Nelsona2d974d2005-03-23 20:50:00 -070065
Dean Nelsona2d974d2005-03-23 20:50:00 -070066#define XPNET_MAX_KTHREADS (XPNET_MSG_NENTRIES + 1)
67#define XPNET_MAX_IDLE_KTHREADS (XPNET_MSG_NENTRIES + 1)
68
69/*
70 * Version number of XPNET implementation. XPNET can always talk to versions
71 * with same major #, and never talk to versions with a different version.
72 */
73#define _XPNET_VERSION(_major, _minor) (((_major) << 4) | (_minor))
74#define XPNET_VERSION_MAJOR(_v) ((_v) >> 4)
75#define XPNET_VERSION_MINOR(_v) ((_v) & 0xf)
76
Dean Nelson2c2b94f2008-04-22 14:50:17 -050077#define XPNET_VERSION _XPNET_VERSION(1, 0) /* version 1.0 */
78#define XPNET_VERSION_EMBED _XPNET_VERSION(1, 1) /* version 1.1 */
Dean Nelson35190502008-04-22 14:48:55 -050079#define XPNET_MAGIC 0x88786984 /* "XNET" */
Dean Nelsona2d974d2005-03-23 20:50:00 -070080
81#define XPNET_VALID_MSG(_m) \
82 ((XPNET_VERSION_MAJOR(_m->version) == XPNET_VERSION_MAJOR(XPNET_VERSION)) \
83 && (msg->magic == XPNET_MAGIC))
84
85#define XPNET_DEVICE_NAME "xp0"
86
Dean Nelsona2d974d2005-03-23 20:50:00 -070087/*
88 * When messages are queued with xpc_send_notify, a kmalloc'd buffer
89 * of the following type is passed as a notification cookie. When the
90 * notification function is called, we use the cookie to decide
91 * whether all outstanding message sends have completed. The skb can
92 * then be released.
93 */
94struct xpnet_pending_msg {
Dean Nelsona2d974d2005-03-23 20:50:00 -070095 struct sk_buff *skb;
96 atomic_t use_count;
97};
98
Dean Nelsona2d974d2005-03-23 20:50:00 -070099struct net_device *xpnet_device;
100
101/*
102 * When we are notified of other partitions activating, we add them to
103 * our bitmask of partitions to which we broadcast.
104 */
Dean Nelsona7b4d502008-07-29 22:34:12 -0700105static unsigned long *xpnet_broadcast_partitions;
Dean Nelsona2d974d2005-03-23 20:50:00 -0700106/* protect above */
Ingo Molnara9f6a0d2005-09-09 13:10:41 -0700107static DEFINE_SPINLOCK(xpnet_broadcast_lock);
Dean Nelsona2d974d2005-03-23 20:50:00 -0700108
109/*
110 * Since the Block Transfer Engine (BTE) is being used for the transfer
111 * and it relies upon cache-line size transfers, we need to reserve at
112 * least one cache-line for head and tail alignment. The BTE is
113 * limited to 8MB transfers.
114 *
115 * Testing has shown that changing MTU to greater than 64KB has no effect
116 * on TCP as the two sides negotiate a Max Segment Size that is limited
117 * to 64K. Other protocols May use packets greater than this, but for
118 * now, the default is 64KB.
119 */
120#define XPNET_MAX_MTU (0x800000UL - L1_CACHE_BYTES)
Jarod Wilsonb3e38932016-10-20 13:55:22 -0400121/* 68 comes from min TCP+IP+MAC header */
122#define XPNET_MIN_MTU 68
Dean Nelsona2d974d2005-03-23 20:50:00 -0700123/* 32KB has been determined to be the ideal */
124#define XPNET_DEF_MTU (0x8000UL)
125
Dean Nelsona2d974d2005-03-23 20:50:00 -0700126/*
Dean Nelsona7b4d502008-07-29 22:34:12 -0700127 * The partid is encapsulated in the MAC address beginning in the following
128 * octet and it consists of two octets.
Dean Nelsona2d974d2005-03-23 20:50:00 -0700129 */
Dean Nelsona7b4d502008-07-29 22:34:12 -0700130#define XPNET_PARTID_OCTET 2
Dean Nelsona2d974d2005-03-23 20:50:00 -0700131
Dean Nelsona7b4d502008-07-29 22:34:12 -0700132/* Define the XPNET debug device structures to be used with dev_dbg() et al */
133
Dean Nelsona2d974d2005-03-23 20:50:00 -0700134struct device_driver xpnet_dbg_name = {
135 .name = "xpnet"
136};
137
138struct device xpnet_dbg_subname = {
Kay Sieversbb0dc432009-01-06 10:44:37 -0800139 .init_name = "", /* set to "" */
Dean Nelsona2d974d2005-03-23 20:50:00 -0700140 .driver = &xpnet_dbg_name
141};
142
143struct device *xpnet = &xpnet_dbg_subname;
144
145/*
146 * Packet was recevied by XPC and forwarded to us.
147 */
148static void
Dean Nelson64d032b2008-05-12 14:02:03 -0700149xpnet_receive(short partid, int channel, struct xpnet_message *msg)
Dean Nelsona2d974d2005-03-23 20:50:00 -0700150{
151 struct sk_buff *skb;
Dean Nelsona812dcc2008-07-29 22:34:16 -0700152 void *dst;
Dean Nelson908787d2008-07-29 22:34:05 -0700153 enum xp_retval ret;
Dean Nelsona2d974d2005-03-23 20:50:00 -0700154
155 if (!XPNET_VALID_MSG(msg)) {
156 /*
157 * Packet with a different XPC version. Ignore.
158 */
Dean Nelson35190502008-04-22 14:48:55 -0500159 xpc_received(partid, channel, (void *)msg);
Dean Nelsona2d974d2005-03-23 20:50:00 -0700160
Stephen Hemmingere8ac9c52009-01-07 18:05:11 -0800161 xpnet_device->stats.rx_errors++;
Dean Nelsona2d974d2005-03-23 20:50:00 -0700162
163 return;
164 }
Dean Nelsona812dcc2008-07-29 22:34:16 -0700165 dev_dbg(xpnet, "received 0x%lx, %d, %d, %d\n", msg->buf_pa, msg->size,
166 msg->leadin_ignore, msg->tailout_ignore);
Dean Nelsona2d974d2005-03-23 20:50:00 -0700167
Dean Nelsona2d974d2005-03-23 20:50:00 -0700168 /* reserve an extra cache line */
169 skb = dev_alloc_skb(msg->size + L1_CACHE_BYTES);
170 if (!skb) {
171 dev_err(xpnet, "failed on dev_alloc_skb(%d)\n",
172 msg->size + L1_CACHE_BYTES);
173
Dean Nelson35190502008-04-22 14:48:55 -0500174 xpc_received(partid, channel, (void *)msg);
Dean Nelsona2d974d2005-03-23 20:50:00 -0700175
Stephen Hemmingere8ac9c52009-01-07 18:05:11 -0800176 xpnet_device->stats.rx_errors++;
Dean Nelsona2d974d2005-03-23 20:50:00 -0700177
178 return;
179 }
180
181 /*
182 * The allocated skb has some reserved space.
Dean Nelson908787d2008-07-29 22:34:05 -0700183 * In order to use xp_remote_memcpy(), we need to get the
Dean Nelsona2d974d2005-03-23 20:50:00 -0700184 * skb->data pointer moved forward.
185 */
186 skb_reserve(skb, (L1_CACHE_BYTES - ((u64)skb->data &
187 (L1_CACHE_BYTES - 1)) +
188 msg->leadin_ignore));
189
190 /*
191 * Update the tail pointer to indicate data actually
192 * transferred.
193 */
194 skb_put(skb, (msg->size - msg->leadin_ignore - msg->tailout_ignore));
195
196 /*
Matt LaPlante4b3f6862006-10-03 22:21:02 +0200197 * Move the data over from the other side.
Dean Nelsona2d974d2005-03-23 20:50:00 -0700198 */
199 if ((XPNET_VERSION_MINOR(msg->version) == 1) &&
Dean Nelson35190502008-04-22 14:48:55 -0500200 (msg->embedded_bytes != 0)) {
Dean Nelsona2d974d2005-03-23 20:50:00 -0700201 dev_dbg(xpnet, "copying embedded message. memcpy(0x%p, 0x%p, "
202 "%lu)\n", skb->data, &msg->data,
Dean Nelson35190502008-04-22 14:48:55 -0500203 (size_t)msg->embedded_bytes);
Dean Nelsona2d974d2005-03-23 20:50:00 -0700204
Dean Nelson35190502008-04-22 14:48:55 -0500205 skb_copy_to_linear_data(skb, &msg->data,
206 (size_t)msg->embedded_bytes);
Dean Nelsona2d974d2005-03-23 20:50:00 -0700207 } else {
Dean Nelsona812dcc2008-07-29 22:34:16 -0700208 dst = (void *)((u64)skb->data & ~(L1_CACHE_BYTES - 1));
Dean Nelsona2d974d2005-03-23 20:50:00 -0700209 dev_dbg(xpnet, "transferring buffer to the skb->data area;\n\t"
Dean Nelsona812dcc2008-07-29 22:34:16 -0700210 "xp_remote_memcpy(0x%p, 0x%p, %hu)\n", dst,
Dean Nelson908787d2008-07-29 22:34:05 -0700211 (void *)msg->buf_pa, msg->size);
Dean Nelsona2d974d2005-03-23 20:50:00 -0700212
Dean Nelsona812dcc2008-07-29 22:34:16 -0700213 ret = xp_remote_memcpy(xp_pa(dst), msg->buf_pa, msg->size);
Dean Nelson908787d2008-07-29 22:34:05 -0700214 if (ret != xpSuccess) {
Dean Nelson2c2b94f2008-04-22 14:50:17 -0500215 /*
Dean Nelsonea57f802008-07-29 22:34:14 -0700216 * !!! Need better way of cleaning skb. Currently skb
217 * !!! appears in_use and we can't just call
218 * !!! dev_kfree_skb.
Dean Nelson2c2b94f2008-04-22 14:50:17 -0500219 */
Dean Nelson908787d2008-07-29 22:34:05 -0700220 dev_err(xpnet, "xp_remote_memcpy(0x%p, 0x%p, 0x%hx) "
Dean Nelsona812dcc2008-07-29 22:34:16 -0700221 "returned error=0x%x\n", dst,
Dean Nelson908787d2008-07-29 22:34:05 -0700222 (void *)msg->buf_pa, msg->size, ret);
Dean Nelsona2d974d2005-03-23 20:50:00 -0700223
Dean Nelson35190502008-04-22 14:48:55 -0500224 xpc_received(partid, channel, (void *)msg);
Dean Nelsona2d974d2005-03-23 20:50:00 -0700225
Stephen Hemmingere8ac9c52009-01-07 18:05:11 -0800226 xpnet_device->stats.rx_errors++;
Dean Nelsona2d974d2005-03-23 20:50:00 -0700227
228 return;
229 }
230 }
231
232 dev_dbg(xpnet, "<skb->head=0x%p skb->data=0x%p skb->tail=0x%p "
Dean Nelson35190502008-04-22 14:48:55 -0500233 "skb->end=0x%p skb->len=%d\n", (void *)skb->head,
Arnaldo Carvalho de Melo4305b542007-04-19 20:43:29 -0700234 (void *)skb->data, skb_tail_pointer(skb), skb_end_pointer(skb),
Dean Nelsona2d974d2005-03-23 20:50:00 -0700235 skb->len);
236
Dean Nelsona2d974d2005-03-23 20:50:00 -0700237 skb->protocol = eth_type_trans(skb, xpnet_device);
238 skb->ip_summed = CHECKSUM_UNNECESSARY;
239
Joe Perches898eb712007-10-18 03:06:30 -0700240 dev_dbg(xpnet, "passing skb to network layer\n"
Joe Perchesad361c92009-07-06 13:05:40 -0700241 "\tskb->head=0x%p skb->data=0x%p skb->tail=0x%p "
Joe Perches898eb712007-10-18 03:06:30 -0700242 "skb->end=0x%p skb->len=%d\n",
Arnaldo Carvalho de Melo27a884d2007-04-19 20:29:13 -0700243 (void *)skb->head, (void *)skb->data, skb_tail_pointer(skb),
Arnaldo Carvalho de Melo4305b542007-04-19 20:43:29 -0700244 skb_end_pointer(skb), skb->len);
Dean Nelsona2d974d2005-03-23 20:50:00 -0700245
Stephen Hemmingere8ac9c52009-01-07 18:05:11 -0800246 xpnet_device->stats.rx_packets++;
247 xpnet_device->stats.rx_bytes += skb->len + ETH_HLEN;
Dean Nelsona2d974d2005-03-23 20:50:00 -0700248
249 netif_rx_ni(skb);
Dean Nelson35190502008-04-22 14:48:55 -0500250 xpc_received(partid, channel, (void *)msg);
Dean Nelsona2d974d2005-03-23 20:50:00 -0700251}
252
Dean Nelsona2d974d2005-03-23 20:50:00 -0700253/*
254 * This is the handler which XPC calls during any sort of change in
255 * state or message reception on a connection.
256 */
257static void
Dean Nelson64d032b2008-05-12 14:02:03 -0700258xpnet_connection_activity(enum xp_retval reason, short partid, int channel,
Dean Nelsona2d974d2005-03-23 20:50:00 -0700259 void *data, void *key)
260{
Dean Nelsonbc63d382008-07-29 22:34:04 -0700261 DBUG_ON(partid < 0 || partid >= xp_max_npartitions);
Dean Nelsona2d974d2005-03-23 20:50:00 -0700262 DBUG_ON(channel != XPC_NET_CHANNEL);
263
Dean Nelson35190502008-04-22 14:48:55 -0500264 switch (reason) {
Dean Nelson65c17b82008-05-12 14:02:02 -0700265 case xpMsgReceived: /* message received */
Dean Nelsona2d974d2005-03-23 20:50:00 -0700266 DBUG_ON(data == NULL);
267
Dean Nelson35190502008-04-22 14:48:55 -0500268 xpnet_receive(partid, channel, (struct xpnet_message *)data);
Dean Nelsona2d974d2005-03-23 20:50:00 -0700269 break;
270
Dean Nelson65c17b82008-05-12 14:02:02 -0700271 case xpConnected: /* connection completed to a partition */
Dean Nelsona2d974d2005-03-23 20:50:00 -0700272 spin_lock_bh(&xpnet_broadcast_lock);
Dean Nelsona7b4d502008-07-29 22:34:12 -0700273 __set_bit(partid, xpnet_broadcast_partitions);
Dean Nelsona2d974d2005-03-23 20:50:00 -0700274 spin_unlock_bh(&xpnet_broadcast_lock);
275
276 netif_carrier_on(xpnet_device);
277
Dean Nelsona7b4d502008-07-29 22:34:12 -0700278 dev_dbg(xpnet, "%s connected to partition %d\n",
279 xpnet_device->name, partid);
Dean Nelsona2d974d2005-03-23 20:50:00 -0700280 break;
281
282 default:
283 spin_lock_bh(&xpnet_broadcast_lock);
Dean Nelsona7b4d502008-07-29 22:34:12 -0700284 __clear_bit(partid, xpnet_broadcast_partitions);
Dean Nelsona2d974d2005-03-23 20:50:00 -0700285 spin_unlock_bh(&xpnet_broadcast_lock);
286
Dean Nelsona7b4d502008-07-29 22:34:12 -0700287 if (bitmap_empty((unsigned long *)xpnet_broadcast_partitions,
288 xp_max_npartitions)) {
Dean Nelsona2d974d2005-03-23 20:50:00 -0700289 netif_carrier_off(xpnet_device);
Dean Nelsona7b4d502008-07-29 22:34:12 -0700290 }
Dean Nelsona2d974d2005-03-23 20:50:00 -0700291
Dean Nelsona7b4d502008-07-29 22:34:12 -0700292 dev_dbg(xpnet, "%s disconnected from partition %d\n",
293 xpnet_device->name, partid);
Dean Nelsona2d974d2005-03-23 20:50:00 -0700294 break;
Dean Nelsona2d974d2005-03-23 20:50:00 -0700295 }
296}
297
Dean Nelsona2d974d2005-03-23 20:50:00 -0700298static int
299xpnet_dev_open(struct net_device *dev)
300{
Dean Nelson65c17b82008-05-12 14:02:02 -0700301 enum xp_retval ret;
Dean Nelsona2d974d2005-03-23 20:50:00 -0700302
Tony Luckb9ae3bd2007-05-10 11:47:38 -0700303 dev_dbg(xpnet, "calling xpc_connect(%d, 0x%p, NULL, %ld, %ld, %ld, "
304 "%ld)\n", XPC_NET_CHANNEL, xpnet_connection_activity,
Dean Nelson261f3b42008-07-29 22:34:16 -0700305 (unsigned long)XPNET_MSG_SIZE,
306 (unsigned long)XPNET_MSG_NENTRIES,
307 (unsigned long)XPNET_MAX_KTHREADS,
308 (unsigned long)XPNET_MAX_IDLE_KTHREADS);
Dean Nelsona2d974d2005-03-23 20:50:00 -0700309
310 ret = xpc_connect(XPC_NET_CHANNEL, xpnet_connection_activity, NULL,
311 XPNET_MSG_SIZE, XPNET_MSG_NENTRIES,
312 XPNET_MAX_KTHREADS, XPNET_MAX_IDLE_KTHREADS);
Dean Nelson65c17b82008-05-12 14:02:02 -0700313 if (ret != xpSuccess) {
Dean Nelsona2d974d2005-03-23 20:50:00 -0700314 dev_err(xpnet, "ifconfig up of %s failed on XPC connect, "
315 "ret=%d\n", dev->name, ret);
316
317 return -ENOMEM;
318 }
319
320 dev_dbg(xpnet, "ifconfig up of %s; XPC connected\n", dev->name);
321
322 return 0;
323}
324
Dean Nelsona2d974d2005-03-23 20:50:00 -0700325static int
326xpnet_dev_stop(struct net_device *dev)
327{
328 xpc_disconnect(XPC_NET_CHANNEL);
329
330 dev_dbg(xpnet, "ifconfig down of %s; XPC disconnected\n", dev->name);
331
332 return 0;
333}
334
Dean Nelsona2d974d2005-03-23 20:50:00 -0700335/*
Dean Nelsona2d974d2005-03-23 20:50:00 -0700336 * Notification that the other end has received the message and
337 * DMA'd the skb information. At this point, they are done with
338 * our side. When all recipients are done processing, we
339 * release the skb and then release our pending message structure.
340 */
341static void
Dean Nelson64d032b2008-05-12 14:02:03 -0700342xpnet_send_completed(enum xp_retval reason, short partid, int channel,
Dean Nelson35190502008-04-22 14:48:55 -0500343 void *__qm)
Dean Nelsona2d974d2005-03-23 20:50:00 -0700344{
Dean Nelson35190502008-04-22 14:48:55 -0500345 struct xpnet_pending_msg *queued_msg = (struct xpnet_pending_msg *)__qm;
Dean Nelsona2d974d2005-03-23 20:50:00 -0700346
347 DBUG_ON(queued_msg == NULL);
348
349 dev_dbg(xpnet, "message to %d notified with reason %d\n",
350 partid, reason);
351
352 if (atomic_dec_return(&queued_msg->use_count) == 0) {
353 dev_dbg(xpnet, "all acks for skb->head=-x%p\n",
Dean Nelson35190502008-04-22 14:48:55 -0500354 (void *)queued_msg->skb->head);
Dean Nelsona2d974d2005-03-23 20:50:00 -0700355
356 dev_kfree_skb_any(queued_msg->skb);
357 kfree(queued_msg);
358 }
359}
360
Dean Nelsona7b4d502008-07-29 22:34:12 -0700361static void
362xpnet_send(struct sk_buff *skb, struct xpnet_pending_msg *queued_msg,
363 u64 start_addr, u64 end_addr, u16 embedded_bytes, int dest_partid)
364{
365 u8 msg_buffer[XPNET_MSG_SIZE];
366 struct xpnet_message *msg = (struct xpnet_message *)&msg_buffer;
Dean Nelsonbd3e64c2008-07-29 22:34:19 -0700367 u16 msg_size = sizeof(struct xpnet_message);
Dean Nelsona7b4d502008-07-29 22:34:12 -0700368 enum xp_retval ret;
369
370 msg->embedded_bytes = embedded_bytes;
371 if (unlikely(embedded_bytes != 0)) {
372 msg->version = XPNET_VERSION_EMBED;
373 dev_dbg(xpnet, "calling memcpy(0x%p, 0x%p, 0x%lx)\n",
374 &msg->data, skb->data, (size_t)embedded_bytes);
375 skb_copy_from_linear_data(skb, &msg->data,
376 (size_t)embedded_bytes);
Dean Nelsonbd3e64c2008-07-29 22:34:19 -0700377 msg_size += embedded_bytes - 1;
Dean Nelsona7b4d502008-07-29 22:34:12 -0700378 } else {
379 msg->version = XPNET_VERSION;
380 }
381 msg->magic = XPNET_MAGIC;
382 msg->size = end_addr - start_addr;
383 msg->leadin_ignore = (u64)skb->data - start_addr;
384 msg->tailout_ignore = end_addr - (u64)skb_tail_pointer(skb);
Dean Nelsona812dcc2008-07-29 22:34:16 -0700385 msg->buf_pa = xp_pa((void *)start_addr);
Dean Nelsona7b4d502008-07-29 22:34:12 -0700386
387 dev_dbg(xpnet, "sending XPC message to %d:%d\n"
Joe Perchesad361c92009-07-06 13:05:40 -0700388 "msg->buf_pa=0x%lx, msg->size=%u, "
Dean Nelsona7b4d502008-07-29 22:34:12 -0700389 "msg->leadin_ignore=%u, msg->tailout_ignore=%u\n",
Dean Nelsona812dcc2008-07-29 22:34:16 -0700390 dest_partid, XPC_NET_CHANNEL, msg->buf_pa, msg->size,
391 msg->leadin_ignore, msg->tailout_ignore);
Dean Nelsona7b4d502008-07-29 22:34:12 -0700392
393 atomic_inc(&queued_msg->use_count);
394
395 ret = xpc_send_notify(dest_partid, XPC_NET_CHANNEL, XPC_NOWAIT, msg,
Dean Nelsonbd3e64c2008-07-29 22:34:19 -0700396 msg_size, xpnet_send_completed, queued_msg);
Dean Nelsona7b4d502008-07-29 22:34:12 -0700397 if (unlikely(ret != xpSuccess))
398 atomic_dec(&queued_msg->use_count);
399}
400
Dean Nelsona2d974d2005-03-23 20:50:00 -0700401/*
402 * Network layer has formatted a packet (skb) and is ready to place it
403 * "on the wire". Prepare and send an xpnet_message to all partitions
404 * which have connected with us and are targets of this packet.
405 *
406 * MAC-NOTE: For the XPNET driver, the MAC address contains the
Dean Nelsona7b4d502008-07-29 22:34:12 -0700407 * destination partid. If the destination partid octets are 0xffff,
408 * this packet is to be broadcast to all connected partitions.
Dean Nelsona2d974d2005-03-23 20:50:00 -0700409 */
Luc Van Oostenryck72b65002018-04-24 15:15:56 +0200410static netdev_tx_t
Dean Nelsona2d974d2005-03-23 20:50:00 -0700411xpnet_dev_hard_start_xmit(struct sk_buff *skb, struct net_device *dev)
412{
413 struct xpnet_pending_msg *queued_msg;
Dean Nelsona2d974d2005-03-23 20:50:00 -0700414 u64 start_addr, end_addr;
Dean Nelson64d032b2008-05-12 14:02:03 -0700415 short dest_partid;
Dean Nelsona7b4d502008-07-29 22:34:12 -0700416 u16 embedded_bytes = 0;
Dean Nelsona2d974d2005-03-23 20:50:00 -0700417
418 dev_dbg(xpnet, ">skb->head=0x%p skb->data=0x%p skb->tail=0x%p "
Dean Nelson35190502008-04-22 14:48:55 -0500419 "skb->end=0x%p skb->len=%d\n", (void *)skb->head,
Arnaldo Carvalho de Melo4305b542007-04-19 20:43:29 -0700420 (void *)skb->data, skb_tail_pointer(skb), skb_end_pointer(skb),
Dean Nelsona2d974d2005-03-23 20:50:00 -0700421 skb->len);
422
Dean Nelsona7b4d502008-07-29 22:34:12 -0700423 if (skb->data[0] == 0x33) {
424 dev_kfree_skb(skb);
Patrick McHardy6ed10652009-06-23 06:03:08 +0000425 return NETDEV_TX_OK; /* nothing needed to be done */
Dean Nelsona7b4d502008-07-29 22:34:12 -0700426 }
427
Dean Nelsona2d974d2005-03-23 20:50:00 -0700428 /*
429 * The xpnet_pending_msg tracks how many outstanding
430 * xpc_send_notifies are relying on this skb. When none
431 * remain, release the skb.
432 */
433 queued_msg = kmalloc(sizeof(struct xpnet_pending_msg), GFP_ATOMIC);
434 if (queued_msg == NULL) {
435 dev_warn(xpnet, "failed to kmalloc %ld bytes; dropping "
Dean Nelson35190502008-04-22 14:48:55 -0500436 "packet\n", sizeof(struct xpnet_pending_msg));
Dean Nelsona2d974d2005-03-23 20:50:00 -0700437
Stephen Hemmingere8ac9c52009-01-07 18:05:11 -0800438 dev->stats.tx_errors++;
Patrick McHardy3790c8c2009-06-12 03:00:35 +0000439 dev_kfree_skb(skb);
440 return NETDEV_TX_OK;
Dean Nelsona2d974d2005-03-23 20:50:00 -0700441 }
442
Dean Nelsona2d974d2005-03-23 20:50:00 -0700443 /* get the beginning of the first cacheline and end of last */
Dean Nelson35190502008-04-22 14:48:55 -0500444 start_addr = ((u64)skb->data & ~(L1_CACHE_BYTES - 1));
Arnaldo Carvalho de Melo27a884d2007-04-19 20:29:13 -0700445 end_addr = L1_CACHE_ALIGN((u64)skb_tail_pointer(skb));
Dean Nelsona2d974d2005-03-23 20:50:00 -0700446
447 /* calculate how many bytes to embed in the XPC message */
Dean Nelsona2d974d2005-03-23 20:50:00 -0700448 if (unlikely(skb->len <= XPNET_MSG_DATA_MAX)) {
449 /* skb->data does fit so embed */
450 embedded_bytes = skb->len;
451 }
452
Dean Nelsona2d974d2005-03-23 20:50:00 -0700453 /*
454 * Since the send occurs asynchronously, we set the count to one
455 * and begin sending. Any sends that happen to complete before
456 * we are done sending will not free the skb. We will be left
457 * with that task during exit. This also handles the case of
458 * a packet destined for a partition which is no longer up.
459 */
460 atomic_set(&queued_msg->use_count, 1);
461 queued_msg->skb = skb;
462
Dean Nelsona7b4d502008-07-29 22:34:12 -0700463 if (skb->data[0] == 0xff) {
Dean Nelsona2d974d2005-03-23 20:50:00 -0700464 /* we are being asked to broadcast to all partitions */
Akinobu Mita984b3f52010-03-05 13:41:37 -0800465 for_each_set_bit(dest_partid, xpnet_broadcast_partitions,
Dean Nelsona7b4d502008-07-29 22:34:12 -0700466 xp_max_npartitions) {
467
468 xpnet_send(skb, queued_msg, start_addr, end_addr,
469 embedded_bytes, dest_partid);
470 }
Dean Nelsona2d974d2005-03-23 20:50:00 -0700471 } else {
Dean Nelsona7b4d502008-07-29 22:34:12 -0700472 dest_partid = (short)skb->data[XPNET_PARTID_OCTET + 1];
473 dest_partid |= (short)skb->data[XPNET_PARTID_OCTET + 0] << 8;
Dean Nelsona2d974d2005-03-23 20:50:00 -0700474
Dean Nelsona7b4d502008-07-29 22:34:12 -0700475 if (dest_partid >= 0 &&
476 dest_partid < xp_max_npartitions &&
477 test_bit(dest_partid, xpnet_broadcast_partitions) != 0) {
Dean Nelsona2d974d2005-03-23 20:50:00 -0700478
Dean Nelsona7b4d502008-07-29 22:34:12 -0700479 xpnet_send(skb, queued_msg, start_addr, end_addr,
480 embedded_bytes, dest_partid);
Dean Nelsona2d974d2005-03-23 20:50:00 -0700481 }
Dean Nelsona2d974d2005-03-23 20:50:00 -0700482 }
483
Eric Dumazet44da29d2011-06-19 12:52:36 +0000484 dev->stats.tx_packets++;
485 dev->stats.tx_bytes += skb->len;
486
Dean Nelsona2d974d2005-03-23 20:50:00 -0700487 if (atomic_dec_return(&queued_msg->use_count) == 0) {
Dean Nelsona2d974d2005-03-23 20:50:00 -0700488 dev_kfree_skb(skb);
489 kfree(queued_msg);
490 }
491
Patrick McHardy6ed10652009-06-23 06:03:08 +0000492 return NETDEV_TX_OK;
Dean Nelsona2d974d2005-03-23 20:50:00 -0700493}
494
Dean Nelsona2d974d2005-03-23 20:50:00 -0700495/*
496 * Deal with transmit timeouts coming from the network layer.
497 */
498static void
Dean Nelson35190502008-04-22 14:48:55 -0500499xpnet_dev_tx_timeout(struct net_device *dev)
Dean Nelsona2d974d2005-03-23 20:50:00 -0700500{
Stephen Hemmingere8ac9c52009-01-07 18:05:11 -0800501 dev->stats.tx_errors++;
Dean Nelsona2d974d2005-03-23 20:50:00 -0700502}
503
Stephen Hemmingere8ac9c52009-01-07 18:05:11 -0800504static const struct net_device_ops xpnet_netdev_ops = {
505 .ndo_open = xpnet_dev_open,
506 .ndo_stop = xpnet_dev_stop,
507 .ndo_start_xmit = xpnet_dev_hard_start_xmit,
Stephen Hemmingere8ac9c52009-01-07 18:05:11 -0800508 .ndo_tx_timeout = xpnet_dev_tx_timeout,
509 .ndo_set_mac_address = eth_mac_addr,
510 .ndo_validate_addr = eth_validate_addr,
511};
512
Dean Nelsona2d974d2005-03-23 20:50:00 -0700513static int __init
514xpnet_init(void)
515{
Dean Nelsona7b4d502008-07-29 22:34:12 -0700516 int result;
Dean Nelsona2d974d2005-03-23 20:50:00 -0700517
Dean Nelsona7b4d502008-07-29 22:34:12 -0700518 if (!is_shub() && !is_uv())
Dean Nelson408865c2005-09-08 10:46:58 -0500519 return -ENODEV;
Dean Nelson408865c2005-09-08 10:46:58 -0500520
Dean Nelsona2d974d2005-03-23 20:50:00 -0700521 dev_info(xpnet, "registering network device %s\n", XPNET_DEVICE_NAME);
522
Kees Cook6396bb22018-06-12 14:03:40 -0700523 xpnet_broadcast_partitions = kcalloc(BITS_TO_LONGS(xp_max_npartitions),
524 sizeof(long),
525 GFP_KERNEL);
Dean Nelsona7b4d502008-07-29 22:34:12 -0700526 if (xpnet_broadcast_partitions == NULL)
527 return -ENOMEM;
528
Dean Nelsona2d974d2005-03-23 20:50:00 -0700529 /*
530 * use ether_setup() to init the majority of our device
531 * structure and then override the necessary pieces.
532 */
Tom Gundersenc835a672014-07-14 16:37:24 +0200533 xpnet_device = alloc_netdev(0, XPNET_DEVICE_NAME, NET_NAME_UNKNOWN,
534 ether_setup);
Dean Nelsona7b4d502008-07-29 22:34:12 -0700535 if (xpnet_device == NULL) {
536 kfree(xpnet_broadcast_partitions);
Dean Nelsona2d974d2005-03-23 20:50:00 -0700537 return -ENOMEM;
Dean Nelsona7b4d502008-07-29 22:34:12 -0700538 }
Dean Nelsona2d974d2005-03-23 20:50:00 -0700539
540 netif_carrier_off(xpnet_device);
541
Dean Nelson714c48f2009-02-03 15:16:17 -0800542 xpnet_device->netdev_ops = &xpnet_netdev_ops;
Dean Nelsona2d974d2005-03-23 20:50:00 -0700543 xpnet_device->mtu = XPNET_DEF_MTU;
Jarod Wilsonb3e38932016-10-20 13:55:22 -0400544 xpnet_device->min_mtu = XPNET_MIN_MTU;
545 xpnet_device->max_mtu = XPNET_MAX_MTU;
Dean Nelsona2d974d2005-03-23 20:50:00 -0700546
547 /*
548 * Multicast assumes the LSB of the first octet is set for multicast
549 * MAC addresses. We chose the first octet of the MAC to be unlikely
550 * to collide with any vendor's officially issued MAC.
551 */
Dean Nelsona7b4d502008-07-29 22:34:12 -0700552 xpnet_device->dev_addr[0] = 0x02; /* locally administered, no OUI */
553
Dean Nelson261f3b42008-07-29 22:34:16 -0700554 xpnet_device->dev_addr[XPNET_PARTID_OCTET + 1] = xp_partition_id;
555 xpnet_device->dev_addr[XPNET_PARTID_OCTET + 0] = (xp_partition_id >> 8);
Dean Nelsona2d974d2005-03-23 20:50:00 -0700556
557 /*
558 * ether_setup() sets this to a multicast device. We are
559 * really not supporting multicast at this time.
560 */
561 xpnet_device->flags &= ~IFF_MULTICAST;
562
563 /*
564 * No need to checksum as it is a DMA transfer. The BTE will
565 * report an error if the data is not retrievable and the
566 * packet will be dropped.
567 */
Michał Mirosław34324dc2011-11-15 15:29:55 +0000568 xpnet_device->features = NETIF_F_HW_CSUM;
Dean Nelsona2d974d2005-03-23 20:50:00 -0700569
570 result = register_netdev(xpnet_device);
Dean Nelsona7b4d502008-07-29 22:34:12 -0700571 if (result != 0) {
Dean Nelsona2d974d2005-03-23 20:50:00 -0700572 free_netdev(xpnet_device);
Dean Nelsona7b4d502008-07-29 22:34:12 -0700573 kfree(xpnet_broadcast_partitions);
574 }
Dean Nelsona2d974d2005-03-23 20:50:00 -0700575
576 return result;
577}
Dean Nelsona2d974d2005-03-23 20:50:00 -0700578
Dean Nelson35190502008-04-22 14:48:55 -0500579module_init(xpnet_init);
Dean Nelsona2d974d2005-03-23 20:50:00 -0700580
581static void __exit
582xpnet_exit(void)
583{
584 dev_info(xpnet, "unregistering network device %s\n",
Dean Nelson35190502008-04-22 14:48:55 -0500585 xpnet_device[0].name);
Dean Nelsona2d974d2005-03-23 20:50:00 -0700586
587 unregister_netdev(xpnet_device);
Dean Nelsona2d974d2005-03-23 20:50:00 -0700588 free_netdev(xpnet_device);
Dean Nelsona7b4d502008-07-29 22:34:12 -0700589 kfree(xpnet_broadcast_partitions);
Dean Nelsona2d974d2005-03-23 20:50:00 -0700590}
Dean Nelsona2d974d2005-03-23 20:50:00 -0700591
Dean Nelson35190502008-04-22 14:48:55 -0500592module_exit(xpnet_exit);
Dean Nelsona2d974d2005-03-23 20:50:00 -0700593
594MODULE_AUTHOR("Silicon Graphics, Inc.");
595MODULE_DESCRIPTION("Cross Partition Network adapter (XPNET)");
596MODULE_LICENSE("GPL");