xref: /openbmc/linux/drivers/net/ethernet/ibm/ibmveth.c (revision d3964221)
1 /*
2  * IBM Power Virtual Ethernet Device Driver
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License as published by
6  * the Free Software Foundation; either version 2 of the License, or
7  * (at your option) any later version.
8  *
9  * This program is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program; if not, see <http://www.gnu.org/licenses/>.
16  *
17  * Copyright (C) IBM Corporation, 2003, 2010
18  *
19  * Authors: Dave Larson <larson1@us.ibm.com>
20  *	    Santiago Leon <santil@linux.vnet.ibm.com>
21  *	    Brian King <brking@linux.vnet.ibm.com>
22  *	    Robert Jennings <rcj@linux.vnet.ibm.com>
23  *	    Anton Blanchard <anton@au.ibm.com>
24  */
25 
26 #include <linux/module.h>
27 #include <linux/moduleparam.h>
28 #include <linux/types.h>
29 #include <linux/errno.h>
30 #include <linux/dma-mapping.h>
31 #include <linux/kernel.h>
32 #include <linux/netdevice.h>
33 #include <linux/etherdevice.h>
34 #include <linux/skbuff.h>
35 #include <linux/init.h>
36 #include <linux/interrupt.h>
37 #include <linux/mm.h>
38 #include <linux/pm.h>
39 #include <linux/ethtool.h>
40 #include <linux/in.h>
41 #include <linux/ip.h>
42 #include <linux/ipv6.h>
43 #include <linux/slab.h>
44 #include <asm/hvcall.h>
45 #include <linux/atomic.h>
46 #include <asm/vio.h>
47 #include <asm/iommu.h>
48 #include <asm/firmware.h>
49 #include <net/tcp.h>
50 #include <net/ip6_checksum.h>
51 
52 #include "ibmveth.h"
53 
54 static irqreturn_t ibmveth_interrupt(int irq, void *dev_instance);
55 static void ibmveth_rxq_harvest_buffer(struct ibmveth_adapter *adapter);
56 static unsigned long ibmveth_get_desired_dma(struct vio_dev *vdev);
57 
58 static struct kobj_type ktype_veth_pool;
59 
60 
61 static const char ibmveth_driver_name[] = "ibmveth";
62 static const char ibmveth_driver_string[] = "IBM Power Virtual Ethernet Driver";
63 #define ibmveth_driver_version "1.06"
64 
65 MODULE_AUTHOR("Santiago Leon <santil@linux.vnet.ibm.com>");
66 MODULE_DESCRIPTION("IBM Power Virtual Ethernet Driver");
67 MODULE_LICENSE("GPL");
68 MODULE_VERSION(ibmveth_driver_version);
69 
70 static unsigned int tx_copybreak __read_mostly = 128;
71 module_param(tx_copybreak, uint, 0644);
72 MODULE_PARM_DESC(tx_copybreak,
73 	"Maximum size of packet that is copied to a new buffer on transmit");
74 
75 static unsigned int rx_copybreak __read_mostly = 128;
76 module_param(rx_copybreak, uint, 0644);
77 MODULE_PARM_DESC(rx_copybreak,
78 	"Maximum size of packet that is copied to a new buffer on receive");
79 
80 static unsigned int rx_flush __read_mostly = 0;
81 module_param(rx_flush, uint, 0644);
82 MODULE_PARM_DESC(rx_flush, "Flush receive buffers before use");
83 
84 static bool old_large_send __read_mostly;
85 module_param(old_large_send, bool, S_IRUGO);
86 MODULE_PARM_DESC(old_large_send,
87 	"Use old large send method on firmware that supports the new method");
88 
89 struct ibmveth_stat {
90 	char name[ETH_GSTRING_LEN];
91 	int offset;
92 };
93 
94 #define IBMVETH_STAT_OFF(stat) offsetof(struct ibmveth_adapter, stat)
95 #define IBMVETH_GET_STAT(a, off) *((u64 *)(((unsigned long)(a)) + off))
96 
97 struct ibmveth_stat ibmveth_stats[] = {
98 	{ "replenish_task_cycles", IBMVETH_STAT_OFF(replenish_task_cycles) },
99 	{ "replenish_no_mem", IBMVETH_STAT_OFF(replenish_no_mem) },
100 	{ "replenish_add_buff_failure",
101 			IBMVETH_STAT_OFF(replenish_add_buff_failure) },
102 	{ "replenish_add_buff_success",
103 			IBMVETH_STAT_OFF(replenish_add_buff_success) },
104 	{ "rx_invalid_buffer", IBMVETH_STAT_OFF(rx_invalid_buffer) },
105 	{ "rx_no_buffer", IBMVETH_STAT_OFF(rx_no_buffer) },
106 	{ "tx_map_failed", IBMVETH_STAT_OFF(tx_map_failed) },
107 	{ "tx_send_failed", IBMVETH_STAT_OFF(tx_send_failed) },
108 	{ "fw_enabled_ipv4_csum", IBMVETH_STAT_OFF(fw_ipv4_csum_support) },
109 	{ "fw_enabled_ipv6_csum", IBMVETH_STAT_OFF(fw_ipv6_csum_support) },
110 	{ "tx_large_packets", IBMVETH_STAT_OFF(tx_large_packets) },
111 	{ "rx_large_packets", IBMVETH_STAT_OFF(rx_large_packets) },
112 	{ "fw_enabled_large_send", IBMVETH_STAT_OFF(fw_large_send_support) }
113 };
114 
115 /* simple methods of getting data from the current rxq entry */
116 static inline u32 ibmveth_rxq_flags(struct ibmveth_adapter *adapter)
117 {
118 	return be32_to_cpu(adapter->rx_queue.queue_addr[adapter->rx_queue.index].flags_off);
119 }
120 
121 static inline int ibmveth_rxq_toggle(struct ibmveth_adapter *adapter)
122 {
123 	return (ibmveth_rxq_flags(adapter) & IBMVETH_RXQ_TOGGLE) >>
124 			IBMVETH_RXQ_TOGGLE_SHIFT;
125 }
126 
127 static inline int ibmveth_rxq_pending_buffer(struct ibmveth_adapter *adapter)
128 {
129 	return ibmveth_rxq_toggle(adapter) == adapter->rx_queue.toggle;
130 }
131 
132 static inline int ibmveth_rxq_buffer_valid(struct ibmveth_adapter *adapter)
133 {
134 	return ibmveth_rxq_flags(adapter) & IBMVETH_RXQ_VALID;
135 }
136 
137 static inline int ibmveth_rxq_frame_offset(struct ibmveth_adapter *adapter)
138 {
139 	return ibmveth_rxq_flags(adapter) & IBMVETH_RXQ_OFF_MASK;
140 }
141 
142 static inline int ibmveth_rxq_large_packet(struct ibmveth_adapter *adapter)
143 {
144 	return ibmveth_rxq_flags(adapter) & IBMVETH_RXQ_LRG_PKT;
145 }
146 
147 static inline int ibmveth_rxq_frame_length(struct ibmveth_adapter *adapter)
148 {
149 	return be32_to_cpu(adapter->rx_queue.queue_addr[adapter->rx_queue.index].length);
150 }
151 
152 static inline int ibmveth_rxq_csum_good(struct ibmveth_adapter *adapter)
153 {
154 	return ibmveth_rxq_flags(adapter) & IBMVETH_RXQ_CSUM_GOOD;
155 }
156 
157 /* setup the initial settings for a buffer pool */
158 static void ibmveth_init_buffer_pool(struct ibmveth_buff_pool *pool,
159 				     u32 pool_index, u32 pool_size,
160 				     u32 buff_size, u32 pool_active)
161 {
162 	pool->size = pool_size;
163 	pool->index = pool_index;
164 	pool->buff_size = buff_size;
165 	pool->threshold = pool_size * 7 / 8;
166 	pool->active = pool_active;
167 }
168 
169 /* allocate and setup an buffer pool - called during open */
170 static int ibmveth_alloc_buffer_pool(struct ibmveth_buff_pool *pool)
171 {
172 	int i;
173 
174 	pool->free_map = kmalloc(sizeof(u16) * pool->size, GFP_KERNEL);
175 
176 	if (!pool->free_map)
177 		return -1;
178 
179 	pool->dma_addr = kcalloc(pool->size, sizeof(dma_addr_t), GFP_KERNEL);
180 	if (!pool->dma_addr) {
181 		kfree(pool->free_map);
182 		pool->free_map = NULL;
183 		return -1;
184 	}
185 
186 	pool->skbuff = kcalloc(pool->size, sizeof(void *), GFP_KERNEL);
187 
188 	if (!pool->skbuff) {
189 		kfree(pool->dma_addr);
190 		pool->dma_addr = NULL;
191 
192 		kfree(pool->free_map);
193 		pool->free_map = NULL;
194 		return -1;
195 	}
196 
197 	for (i = 0; i < pool->size; ++i)
198 		pool->free_map[i] = i;
199 
200 	atomic_set(&pool->available, 0);
201 	pool->producer_index = 0;
202 	pool->consumer_index = 0;
203 
204 	return 0;
205 }
206 
207 static inline void ibmveth_flush_buffer(void *addr, unsigned long length)
208 {
209 	unsigned long offset;
210 
211 	for (offset = 0; offset < length; offset += SMP_CACHE_BYTES)
212 		asm("dcbfl %0,%1" :: "b" (addr), "r" (offset));
213 }
214 
215 /* replenish the buffers for a pool.  note that we don't need to
216  * skb_reserve these since they are used for incoming...
217  */
218 static void ibmveth_replenish_buffer_pool(struct ibmveth_adapter *adapter,
219 					  struct ibmveth_buff_pool *pool)
220 {
221 	u32 i;
222 	u32 count = pool->size - atomic_read(&pool->available);
223 	u32 buffers_added = 0;
224 	struct sk_buff *skb;
225 	unsigned int free_index, index;
226 	u64 correlator;
227 	unsigned long lpar_rc;
228 	dma_addr_t dma_addr;
229 
230 	mb();
231 
232 	for (i = 0; i < count; ++i) {
233 		union ibmveth_buf_desc desc;
234 
235 		skb = netdev_alloc_skb(adapter->netdev, pool->buff_size);
236 
237 		if (!skb) {
238 			netdev_dbg(adapter->netdev,
239 				   "replenish: unable to allocate skb\n");
240 			adapter->replenish_no_mem++;
241 			break;
242 		}
243 
244 		free_index = pool->consumer_index;
245 		pool->consumer_index++;
246 		if (pool->consumer_index >= pool->size)
247 			pool->consumer_index = 0;
248 		index = pool->free_map[free_index];
249 
250 		BUG_ON(index == IBM_VETH_INVALID_MAP);
251 		BUG_ON(pool->skbuff[index] != NULL);
252 
253 		dma_addr = dma_map_single(&adapter->vdev->dev, skb->data,
254 				pool->buff_size, DMA_FROM_DEVICE);
255 
256 		if (dma_mapping_error(&adapter->vdev->dev, dma_addr))
257 			goto failure;
258 
259 		pool->free_map[free_index] = IBM_VETH_INVALID_MAP;
260 		pool->dma_addr[index] = dma_addr;
261 		pool->skbuff[index] = skb;
262 
263 		correlator = ((u64)pool->index << 32) | index;
264 		*(u64 *)skb->data = correlator;
265 
266 		desc.fields.flags_len = IBMVETH_BUF_VALID | pool->buff_size;
267 		desc.fields.address = dma_addr;
268 
269 		if (rx_flush) {
270 			unsigned int len = min(pool->buff_size,
271 						adapter->netdev->mtu +
272 						IBMVETH_BUFF_OH);
273 			ibmveth_flush_buffer(skb->data, len);
274 		}
275 		lpar_rc = h_add_logical_lan_buffer(adapter->vdev->unit_address,
276 						   desc.desc);
277 
278 		if (lpar_rc != H_SUCCESS) {
279 			goto failure;
280 		} else {
281 			buffers_added++;
282 			adapter->replenish_add_buff_success++;
283 		}
284 	}
285 
286 	mb();
287 	atomic_add(buffers_added, &(pool->available));
288 	return;
289 
290 failure:
291 	pool->free_map[free_index] = index;
292 	pool->skbuff[index] = NULL;
293 	if (pool->consumer_index == 0)
294 		pool->consumer_index = pool->size - 1;
295 	else
296 		pool->consumer_index--;
297 	if (!dma_mapping_error(&adapter->vdev->dev, dma_addr))
298 		dma_unmap_single(&adapter->vdev->dev,
299 		                 pool->dma_addr[index], pool->buff_size,
300 		                 DMA_FROM_DEVICE);
301 	dev_kfree_skb_any(skb);
302 	adapter->replenish_add_buff_failure++;
303 
304 	mb();
305 	atomic_add(buffers_added, &(pool->available));
306 }
307 
308 /*
309  * The final 8 bytes of the buffer list is a counter of frames dropped
310  * because there was not a buffer in the buffer list capable of holding
311  * the frame.
312  */
313 static void ibmveth_update_rx_no_buffer(struct ibmveth_adapter *adapter)
314 {
315 	__be64 *p = adapter->buffer_list_addr + 4096 - 8;
316 
317 	adapter->rx_no_buffer = be64_to_cpup(p);
318 }
319 
320 /* replenish routine */
321 static void ibmveth_replenish_task(struct ibmveth_adapter *adapter)
322 {
323 	int i;
324 
325 	adapter->replenish_task_cycles++;
326 
327 	for (i = (IBMVETH_NUM_BUFF_POOLS - 1); i >= 0; i--) {
328 		struct ibmveth_buff_pool *pool = &adapter->rx_buff_pool[i];
329 
330 		if (pool->active &&
331 		    (atomic_read(&pool->available) < pool->threshold))
332 			ibmveth_replenish_buffer_pool(adapter, pool);
333 	}
334 
335 	ibmveth_update_rx_no_buffer(adapter);
336 }
337 
338 /* empty and free ana buffer pool - also used to do cleanup in error paths */
339 static void ibmveth_free_buffer_pool(struct ibmveth_adapter *adapter,
340 				     struct ibmveth_buff_pool *pool)
341 {
342 	int i;
343 
344 	kfree(pool->free_map);
345 	pool->free_map = NULL;
346 
347 	if (pool->skbuff && pool->dma_addr) {
348 		for (i = 0; i < pool->size; ++i) {
349 			struct sk_buff *skb = pool->skbuff[i];
350 			if (skb) {
351 				dma_unmap_single(&adapter->vdev->dev,
352 						 pool->dma_addr[i],
353 						 pool->buff_size,
354 						 DMA_FROM_DEVICE);
355 				dev_kfree_skb_any(skb);
356 				pool->skbuff[i] = NULL;
357 			}
358 		}
359 	}
360 
361 	if (pool->dma_addr) {
362 		kfree(pool->dma_addr);
363 		pool->dma_addr = NULL;
364 	}
365 
366 	if (pool->skbuff) {
367 		kfree(pool->skbuff);
368 		pool->skbuff = NULL;
369 	}
370 }
371 
372 /* remove a buffer from a pool */
373 static void ibmveth_remove_buffer_from_pool(struct ibmveth_adapter *adapter,
374 					    u64 correlator)
375 {
376 	unsigned int pool  = correlator >> 32;
377 	unsigned int index = correlator & 0xffffffffUL;
378 	unsigned int free_index;
379 	struct sk_buff *skb;
380 
381 	BUG_ON(pool >= IBMVETH_NUM_BUFF_POOLS);
382 	BUG_ON(index >= adapter->rx_buff_pool[pool].size);
383 
384 	skb = adapter->rx_buff_pool[pool].skbuff[index];
385 
386 	BUG_ON(skb == NULL);
387 
388 	adapter->rx_buff_pool[pool].skbuff[index] = NULL;
389 
390 	dma_unmap_single(&adapter->vdev->dev,
391 			 adapter->rx_buff_pool[pool].dma_addr[index],
392 			 adapter->rx_buff_pool[pool].buff_size,
393 			 DMA_FROM_DEVICE);
394 
395 	free_index = adapter->rx_buff_pool[pool].producer_index;
396 	adapter->rx_buff_pool[pool].producer_index++;
397 	if (adapter->rx_buff_pool[pool].producer_index >=
398 	    adapter->rx_buff_pool[pool].size)
399 		adapter->rx_buff_pool[pool].producer_index = 0;
400 	adapter->rx_buff_pool[pool].free_map[free_index] = index;
401 
402 	mb();
403 
404 	atomic_dec(&(adapter->rx_buff_pool[pool].available));
405 }
406 
407 /* get the current buffer on the rx queue */
408 static inline struct sk_buff *ibmveth_rxq_get_buffer(struct ibmveth_adapter *adapter)
409 {
410 	u64 correlator = adapter->rx_queue.queue_addr[adapter->rx_queue.index].correlator;
411 	unsigned int pool = correlator >> 32;
412 	unsigned int index = correlator & 0xffffffffUL;
413 
414 	BUG_ON(pool >= IBMVETH_NUM_BUFF_POOLS);
415 	BUG_ON(index >= adapter->rx_buff_pool[pool].size);
416 
417 	return adapter->rx_buff_pool[pool].skbuff[index];
418 }
419 
420 /* recycle the current buffer on the rx queue */
421 static int ibmveth_rxq_recycle_buffer(struct ibmveth_adapter *adapter)
422 {
423 	u32 q_index = adapter->rx_queue.index;
424 	u64 correlator = adapter->rx_queue.queue_addr[q_index].correlator;
425 	unsigned int pool = correlator >> 32;
426 	unsigned int index = correlator & 0xffffffffUL;
427 	union ibmveth_buf_desc desc;
428 	unsigned long lpar_rc;
429 	int ret = 1;
430 
431 	BUG_ON(pool >= IBMVETH_NUM_BUFF_POOLS);
432 	BUG_ON(index >= adapter->rx_buff_pool[pool].size);
433 
434 	if (!adapter->rx_buff_pool[pool].active) {
435 		ibmveth_rxq_harvest_buffer(adapter);
436 		ibmveth_free_buffer_pool(adapter, &adapter->rx_buff_pool[pool]);
437 		goto out;
438 	}
439 
440 	desc.fields.flags_len = IBMVETH_BUF_VALID |
441 		adapter->rx_buff_pool[pool].buff_size;
442 	desc.fields.address = adapter->rx_buff_pool[pool].dma_addr[index];
443 
444 	lpar_rc = h_add_logical_lan_buffer(adapter->vdev->unit_address, desc.desc);
445 
446 	if (lpar_rc != H_SUCCESS) {
447 		netdev_dbg(adapter->netdev, "h_add_logical_lan_buffer failed "
448 			   "during recycle rc=%ld", lpar_rc);
449 		ibmveth_remove_buffer_from_pool(adapter, adapter->rx_queue.queue_addr[adapter->rx_queue.index].correlator);
450 		ret = 0;
451 	}
452 
453 	if (++adapter->rx_queue.index == adapter->rx_queue.num_slots) {
454 		adapter->rx_queue.index = 0;
455 		adapter->rx_queue.toggle = !adapter->rx_queue.toggle;
456 	}
457 
458 out:
459 	return ret;
460 }
461 
462 static void ibmveth_rxq_harvest_buffer(struct ibmveth_adapter *adapter)
463 {
464 	ibmveth_remove_buffer_from_pool(adapter, adapter->rx_queue.queue_addr[adapter->rx_queue.index].correlator);
465 
466 	if (++adapter->rx_queue.index == adapter->rx_queue.num_slots) {
467 		adapter->rx_queue.index = 0;
468 		adapter->rx_queue.toggle = !adapter->rx_queue.toggle;
469 	}
470 }
471 
472 static int ibmveth_register_logical_lan(struct ibmveth_adapter *adapter,
473         union ibmveth_buf_desc rxq_desc, u64 mac_address)
474 {
475 	int rc, try_again = 1;
476 
477 	/*
478 	 * After a kexec the adapter will still be open, so our attempt to
479 	 * open it will fail. So if we get a failure we free the adapter and
480 	 * try again, but only once.
481 	 */
482 retry:
483 	rc = h_register_logical_lan(adapter->vdev->unit_address,
484 				    adapter->buffer_list_dma, rxq_desc.desc,
485 				    adapter->filter_list_dma, mac_address);
486 
487 	if (rc != H_SUCCESS && try_again) {
488 		do {
489 			rc = h_free_logical_lan(adapter->vdev->unit_address);
490 		} while (H_IS_LONG_BUSY(rc) || (rc == H_BUSY));
491 
492 		try_again = 0;
493 		goto retry;
494 	}
495 
496 	return rc;
497 }
498 
499 static u64 ibmveth_encode_mac_addr(u8 *mac)
500 {
501 	int i;
502 	u64 encoded = 0;
503 
504 	for (i = 0; i < ETH_ALEN; i++)
505 		encoded = (encoded << 8) | mac[i];
506 
507 	return encoded;
508 }
509 
510 static int ibmveth_open(struct net_device *netdev)
511 {
512 	struct ibmveth_adapter *adapter = netdev_priv(netdev);
513 	u64 mac_address;
514 	int rxq_entries = 1;
515 	unsigned long lpar_rc;
516 	int rc;
517 	union ibmveth_buf_desc rxq_desc;
518 	int i;
519 	struct device *dev;
520 
521 	netdev_dbg(netdev, "open starting\n");
522 
523 	napi_enable(&adapter->napi);
524 
525 	for(i = 0; i < IBMVETH_NUM_BUFF_POOLS; i++)
526 		rxq_entries += adapter->rx_buff_pool[i].size;
527 
528 	rc = -ENOMEM;
529 	adapter->buffer_list_addr = (void*) get_zeroed_page(GFP_KERNEL);
530 	if (!adapter->buffer_list_addr) {
531 		netdev_err(netdev, "unable to allocate list pages\n");
532 		goto out;
533 	}
534 
535 	adapter->filter_list_addr = (void*) get_zeroed_page(GFP_KERNEL);
536 	if (!adapter->filter_list_addr) {
537 		netdev_err(netdev, "unable to allocate filter pages\n");
538 		goto out_free_buffer_list;
539 	}
540 
541 	dev = &adapter->vdev->dev;
542 
543 	adapter->rx_queue.queue_len = sizeof(struct ibmveth_rx_q_entry) *
544 						rxq_entries;
545 	adapter->rx_queue.queue_addr =
546 		dma_alloc_coherent(dev, adapter->rx_queue.queue_len,
547 				   &adapter->rx_queue.queue_dma, GFP_KERNEL);
548 	if (!adapter->rx_queue.queue_addr)
549 		goto out_free_filter_list;
550 
551 	adapter->buffer_list_dma = dma_map_single(dev,
552 			adapter->buffer_list_addr, 4096, DMA_BIDIRECTIONAL);
553 	if (dma_mapping_error(dev, adapter->buffer_list_dma)) {
554 		netdev_err(netdev, "unable to map buffer list pages\n");
555 		goto out_free_queue_mem;
556 	}
557 
558 	adapter->filter_list_dma = dma_map_single(dev,
559 			adapter->filter_list_addr, 4096, DMA_BIDIRECTIONAL);
560 	if (dma_mapping_error(dev, adapter->filter_list_dma)) {
561 		netdev_err(netdev, "unable to map filter list pages\n");
562 		goto out_unmap_buffer_list;
563 	}
564 
565 	adapter->rx_queue.index = 0;
566 	adapter->rx_queue.num_slots = rxq_entries;
567 	adapter->rx_queue.toggle = 1;
568 
569 	mac_address = ibmveth_encode_mac_addr(netdev->dev_addr);
570 
571 	rxq_desc.fields.flags_len = IBMVETH_BUF_VALID |
572 					adapter->rx_queue.queue_len;
573 	rxq_desc.fields.address = adapter->rx_queue.queue_dma;
574 
575 	netdev_dbg(netdev, "buffer list @ 0x%p\n", adapter->buffer_list_addr);
576 	netdev_dbg(netdev, "filter list @ 0x%p\n", adapter->filter_list_addr);
577 	netdev_dbg(netdev, "receive q   @ 0x%p\n", adapter->rx_queue.queue_addr);
578 
579 	h_vio_signal(adapter->vdev->unit_address, VIO_IRQ_DISABLE);
580 
581 	lpar_rc = ibmveth_register_logical_lan(adapter, rxq_desc, mac_address);
582 
583 	if (lpar_rc != H_SUCCESS) {
584 		netdev_err(netdev, "h_register_logical_lan failed with %ld\n",
585 			   lpar_rc);
586 		netdev_err(netdev, "buffer TCE:0x%llx filter TCE:0x%llx rxq "
587 			   "desc:0x%llx MAC:0x%llx\n",
588 				     adapter->buffer_list_dma,
589 				     adapter->filter_list_dma,
590 				     rxq_desc.desc,
591 				     mac_address);
592 		rc = -ENONET;
593 		goto out_unmap_filter_list;
594 	}
595 
596 	for (i = 0; i < IBMVETH_NUM_BUFF_POOLS; i++) {
597 		if (!adapter->rx_buff_pool[i].active)
598 			continue;
599 		if (ibmveth_alloc_buffer_pool(&adapter->rx_buff_pool[i])) {
600 			netdev_err(netdev, "unable to alloc pool\n");
601 			adapter->rx_buff_pool[i].active = 0;
602 			rc = -ENOMEM;
603 			goto out_free_buffer_pools;
604 		}
605 	}
606 
607 	netdev_dbg(netdev, "registering irq 0x%x\n", netdev->irq);
608 	rc = request_irq(netdev->irq, ibmveth_interrupt, 0, netdev->name,
609 			 netdev);
610 	if (rc != 0) {
611 		netdev_err(netdev, "unable to request irq 0x%x, rc %d\n",
612 			   netdev->irq, rc);
613 		do {
614 			lpar_rc = h_free_logical_lan(adapter->vdev->unit_address);
615 		} while (H_IS_LONG_BUSY(lpar_rc) || (lpar_rc == H_BUSY));
616 
617 		goto out_free_buffer_pools;
618 	}
619 
620 	rc = -ENOMEM;
621 	adapter->bounce_buffer =
622 	    kmalloc(netdev->mtu + IBMVETH_BUFF_OH, GFP_KERNEL);
623 	if (!adapter->bounce_buffer)
624 		goto out_free_irq;
625 
626 	adapter->bounce_buffer_dma =
627 	    dma_map_single(&adapter->vdev->dev, adapter->bounce_buffer,
628 			   netdev->mtu + IBMVETH_BUFF_OH, DMA_BIDIRECTIONAL);
629 	if (dma_mapping_error(dev, adapter->bounce_buffer_dma)) {
630 		netdev_err(netdev, "unable to map bounce buffer\n");
631 		goto out_free_bounce_buffer;
632 	}
633 
634 	netdev_dbg(netdev, "initial replenish cycle\n");
635 	ibmveth_interrupt(netdev->irq, netdev);
636 
637 	netif_start_queue(netdev);
638 
639 	netdev_dbg(netdev, "open complete\n");
640 
641 	return 0;
642 
643 out_free_bounce_buffer:
644 	kfree(adapter->bounce_buffer);
645 out_free_irq:
646 	free_irq(netdev->irq, netdev);
647 out_free_buffer_pools:
648 	while (--i >= 0) {
649 		if (adapter->rx_buff_pool[i].active)
650 			ibmveth_free_buffer_pool(adapter,
651 						 &adapter->rx_buff_pool[i]);
652 	}
653 out_unmap_filter_list:
654 	dma_unmap_single(dev, adapter->filter_list_dma, 4096,
655 			 DMA_BIDIRECTIONAL);
656 out_unmap_buffer_list:
657 	dma_unmap_single(dev, adapter->buffer_list_dma, 4096,
658 			 DMA_BIDIRECTIONAL);
659 out_free_queue_mem:
660 	dma_free_coherent(dev, adapter->rx_queue.queue_len,
661 			  adapter->rx_queue.queue_addr,
662 			  adapter->rx_queue.queue_dma);
663 out_free_filter_list:
664 	free_page((unsigned long)adapter->filter_list_addr);
665 out_free_buffer_list:
666 	free_page((unsigned long)adapter->buffer_list_addr);
667 out:
668 	napi_disable(&adapter->napi);
669 	return rc;
670 }
671 
672 static int ibmveth_close(struct net_device *netdev)
673 {
674 	struct ibmveth_adapter *adapter = netdev_priv(netdev);
675 	struct device *dev = &adapter->vdev->dev;
676 	long lpar_rc;
677 	int i;
678 
679 	netdev_dbg(netdev, "close starting\n");
680 
681 	napi_disable(&adapter->napi);
682 
683 	if (!adapter->pool_config)
684 		netif_stop_queue(netdev);
685 
686 	h_vio_signal(adapter->vdev->unit_address, VIO_IRQ_DISABLE);
687 
688 	do {
689 		lpar_rc = h_free_logical_lan(adapter->vdev->unit_address);
690 	} while (H_IS_LONG_BUSY(lpar_rc) || (lpar_rc == H_BUSY));
691 
692 	if (lpar_rc != H_SUCCESS) {
693 		netdev_err(netdev, "h_free_logical_lan failed with %lx, "
694 			   "continuing with close\n", lpar_rc);
695 	}
696 
697 	free_irq(netdev->irq, netdev);
698 
699 	ibmveth_update_rx_no_buffer(adapter);
700 
701 	dma_unmap_single(dev, adapter->buffer_list_dma, 4096,
702 			 DMA_BIDIRECTIONAL);
703 	free_page((unsigned long)adapter->buffer_list_addr);
704 
705 	dma_unmap_single(dev, adapter->filter_list_dma, 4096,
706 			 DMA_BIDIRECTIONAL);
707 	free_page((unsigned long)adapter->filter_list_addr);
708 
709 	dma_free_coherent(dev, adapter->rx_queue.queue_len,
710 			  adapter->rx_queue.queue_addr,
711 			  adapter->rx_queue.queue_dma);
712 
713 	for (i = 0; i < IBMVETH_NUM_BUFF_POOLS; i++)
714 		if (adapter->rx_buff_pool[i].active)
715 			ibmveth_free_buffer_pool(adapter,
716 						 &adapter->rx_buff_pool[i]);
717 
718 	dma_unmap_single(&adapter->vdev->dev, adapter->bounce_buffer_dma,
719 			 adapter->netdev->mtu + IBMVETH_BUFF_OH,
720 			 DMA_BIDIRECTIONAL);
721 	kfree(adapter->bounce_buffer);
722 
723 	netdev_dbg(netdev, "close complete\n");
724 
725 	return 0;
726 }
727 
728 static int netdev_get_link_ksettings(struct net_device *dev,
729 				     struct ethtool_link_ksettings *cmd)
730 {
731 	u32 supported, advertising;
732 
733 	supported = (SUPPORTED_1000baseT_Full | SUPPORTED_Autoneg |
734 				SUPPORTED_FIBRE);
735 	advertising = (ADVERTISED_1000baseT_Full | ADVERTISED_Autoneg |
736 				ADVERTISED_FIBRE);
737 	cmd->base.speed = SPEED_1000;
738 	cmd->base.duplex = DUPLEX_FULL;
739 	cmd->base.port = PORT_FIBRE;
740 	cmd->base.phy_address = 0;
741 	cmd->base.autoneg = AUTONEG_ENABLE;
742 
743 	ethtool_convert_legacy_u32_to_link_mode(cmd->link_modes.supported,
744 						supported);
745 	ethtool_convert_legacy_u32_to_link_mode(cmd->link_modes.advertising,
746 						advertising);
747 
748 	return 0;
749 }
750 
751 static void netdev_get_drvinfo(struct net_device *dev,
752 			       struct ethtool_drvinfo *info)
753 {
754 	strlcpy(info->driver, ibmveth_driver_name, sizeof(info->driver));
755 	strlcpy(info->version, ibmveth_driver_version, sizeof(info->version));
756 }
757 
758 static netdev_features_t ibmveth_fix_features(struct net_device *dev,
759 	netdev_features_t features)
760 {
761 	/*
762 	 * Since the ibmveth firmware interface does not have the
763 	 * concept of separate tx/rx checksum offload enable, if rx
764 	 * checksum is disabled we also have to disable tx checksum
765 	 * offload. Once we disable rx checksum offload, we are no
766 	 * longer allowed to send tx buffers that are not properly
767 	 * checksummed.
768 	 */
769 
770 	if (!(features & NETIF_F_RXCSUM))
771 		features &= ~NETIF_F_CSUM_MASK;
772 
773 	return features;
774 }
775 
776 static int ibmveth_set_csum_offload(struct net_device *dev, u32 data)
777 {
778 	struct ibmveth_adapter *adapter = netdev_priv(dev);
779 	unsigned long set_attr, clr_attr, ret_attr;
780 	unsigned long set_attr6, clr_attr6;
781 	long ret, ret4, ret6;
782 	int rc1 = 0, rc2 = 0;
783 	int restart = 0;
784 
785 	if (netif_running(dev)) {
786 		restart = 1;
787 		adapter->pool_config = 1;
788 		ibmveth_close(dev);
789 		adapter->pool_config = 0;
790 	}
791 
792 	set_attr = 0;
793 	clr_attr = 0;
794 	set_attr6 = 0;
795 	clr_attr6 = 0;
796 
797 	if (data) {
798 		set_attr = IBMVETH_ILLAN_IPV4_TCP_CSUM;
799 		set_attr6 = IBMVETH_ILLAN_IPV6_TCP_CSUM;
800 	} else {
801 		clr_attr = IBMVETH_ILLAN_IPV4_TCP_CSUM;
802 		clr_attr6 = IBMVETH_ILLAN_IPV6_TCP_CSUM;
803 	}
804 
805 	ret = h_illan_attributes(adapter->vdev->unit_address, 0, 0, &ret_attr);
806 
807 	if (ret == H_SUCCESS &&
808 	    (ret_attr & IBMVETH_ILLAN_PADDED_PKT_CSUM)) {
809 		ret4 = h_illan_attributes(adapter->vdev->unit_address, clr_attr,
810 					 set_attr, &ret_attr);
811 
812 		if (ret4 != H_SUCCESS) {
813 			netdev_err(dev, "unable to change IPv4 checksum "
814 					"offload settings. %d rc=%ld\n",
815 					data, ret4);
816 
817 			h_illan_attributes(adapter->vdev->unit_address,
818 					   set_attr, clr_attr, &ret_attr);
819 
820 			if (data == 1)
821 				dev->features &= ~NETIF_F_IP_CSUM;
822 
823 		} else {
824 			adapter->fw_ipv4_csum_support = data;
825 		}
826 
827 		ret6 = h_illan_attributes(adapter->vdev->unit_address,
828 					 clr_attr6, set_attr6, &ret_attr);
829 
830 		if (ret6 != H_SUCCESS) {
831 			netdev_err(dev, "unable to change IPv6 checksum "
832 					"offload settings. %d rc=%ld\n",
833 					data, ret6);
834 
835 			h_illan_attributes(adapter->vdev->unit_address,
836 					   set_attr6, clr_attr6, &ret_attr);
837 
838 			if (data == 1)
839 				dev->features &= ~NETIF_F_IPV6_CSUM;
840 
841 		} else
842 			adapter->fw_ipv6_csum_support = data;
843 
844 		if (ret4 == H_SUCCESS || ret6 == H_SUCCESS)
845 			adapter->rx_csum = data;
846 		else
847 			rc1 = -EIO;
848 	} else {
849 		rc1 = -EIO;
850 		netdev_err(dev, "unable to change checksum offload settings."
851 				     " %d rc=%ld ret_attr=%lx\n", data, ret,
852 				     ret_attr);
853 	}
854 
855 	if (restart)
856 		rc2 = ibmveth_open(dev);
857 
858 	return rc1 ? rc1 : rc2;
859 }
860 
861 static int ibmveth_set_tso(struct net_device *dev, u32 data)
862 {
863 	struct ibmveth_adapter *adapter = netdev_priv(dev);
864 	unsigned long set_attr, clr_attr, ret_attr;
865 	long ret1, ret2;
866 	int rc1 = 0, rc2 = 0;
867 	int restart = 0;
868 
869 	if (netif_running(dev)) {
870 		restart = 1;
871 		adapter->pool_config = 1;
872 		ibmveth_close(dev);
873 		adapter->pool_config = 0;
874 	}
875 
876 	set_attr = 0;
877 	clr_attr = 0;
878 
879 	if (data)
880 		set_attr = IBMVETH_ILLAN_LRG_SR_ENABLED;
881 	else
882 		clr_attr = IBMVETH_ILLAN_LRG_SR_ENABLED;
883 
884 	ret1 = h_illan_attributes(adapter->vdev->unit_address, 0, 0, &ret_attr);
885 
886 	if (ret1 == H_SUCCESS && (ret_attr & IBMVETH_ILLAN_LRG_SND_SUPPORT) &&
887 	    !old_large_send) {
888 		ret2 = h_illan_attributes(adapter->vdev->unit_address, clr_attr,
889 					  set_attr, &ret_attr);
890 
891 		if (ret2 != H_SUCCESS) {
892 			netdev_err(dev, "unable to change tso settings. %d rc=%ld\n",
893 				   data, ret2);
894 
895 			h_illan_attributes(adapter->vdev->unit_address,
896 					   set_attr, clr_attr, &ret_attr);
897 
898 			if (data == 1)
899 				dev->features &= ~(NETIF_F_TSO | NETIF_F_TSO6);
900 			rc1 = -EIO;
901 
902 		} else {
903 			adapter->fw_large_send_support = data;
904 			adapter->large_send = data;
905 		}
906 	} else {
907 		/* Older firmware version of large send offload does not
908 		 * support tcp6/ipv6
909 		 */
910 		if (data == 1) {
911 			dev->features &= ~NETIF_F_TSO6;
912 			netdev_info(dev, "TSO feature requires all partitions to have updated driver");
913 		}
914 		adapter->large_send = data;
915 	}
916 
917 	if (restart)
918 		rc2 = ibmveth_open(dev);
919 
920 	return rc1 ? rc1 : rc2;
921 }
922 
923 static int ibmveth_set_features(struct net_device *dev,
924 	netdev_features_t features)
925 {
926 	struct ibmveth_adapter *adapter = netdev_priv(dev);
927 	int rx_csum = !!(features & NETIF_F_RXCSUM);
928 	int large_send = !!(features & (NETIF_F_TSO | NETIF_F_TSO6));
929 	int rc1 = 0, rc2 = 0;
930 
931 	if (rx_csum != adapter->rx_csum) {
932 		rc1 = ibmveth_set_csum_offload(dev, rx_csum);
933 		if (rc1 && !adapter->rx_csum)
934 			dev->features =
935 				features & ~(NETIF_F_CSUM_MASK |
936 					     NETIF_F_RXCSUM);
937 	}
938 
939 	if (large_send != adapter->large_send) {
940 		rc2 = ibmveth_set_tso(dev, large_send);
941 		if (rc2 && !adapter->large_send)
942 			dev->features =
943 				features & ~(NETIF_F_TSO | NETIF_F_TSO6);
944 	}
945 
946 	return rc1 ? rc1 : rc2;
947 }
948 
949 static void ibmveth_get_strings(struct net_device *dev, u32 stringset, u8 *data)
950 {
951 	int i;
952 
953 	if (stringset != ETH_SS_STATS)
954 		return;
955 
956 	for (i = 0; i < ARRAY_SIZE(ibmveth_stats); i++, data += ETH_GSTRING_LEN)
957 		memcpy(data, ibmveth_stats[i].name, ETH_GSTRING_LEN);
958 }
959 
960 static int ibmveth_get_sset_count(struct net_device *dev, int sset)
961 {
962 	switch (sset) {
963 	case ETH_SS_STATS:
964 		return ARRAY_SIZE(ibmveth_stats);
965 	default:
966 		return -EOPNOTSUPP;
967 	}
968 }
969 
970 static void ibmveth_get_ethtool_stats(struct net_device *dev,
971 				      struct ethtool_stats *stats, u64 *data)
972 {
973 	int i;
974 	struct ibmveth_adapter *adapter = netdev_priv(dev);
975 
976 	for (i = 0; i < ARRAY_SIZE(ibmveth_stats); i++)
977 		data[i] = IBMVETH_GET_STAT(adapter, ibmveth_stats[i].offset);
978 }
979 
980 static const struct ethtool_ops netdev_ethtool_ops = {
981 	.get_drvinfo		= netdev_get_drvinfo,
982 	.get_link		= ethtool_op_get_link,
983 	.get_strings		= ibmveth_get_strings,
984 	.get_sset_count		= ibmveth_get_sset_count,
985 	.get_ethtool_stats	= ibmveth_get_ethtool_stats,
986 	.get_link_ksettings	= netdev_get_link_ksettings,
987 };
988 
989 static int ibmveth_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
990 {
991 	return -EOPNOTSUPP;
992 }
993 
994 #define page_offset(v) ((unsigned long)(v) & ((1 << 12) - 1))
995 
996 static int ibmveth_send(struct ibmveth_adapter *adapter,
997 			union ibmveth_buf_desc *descs, unsigned long mss)
998 {
999 	unsigned long correlator;
1000 	unsigned int retry_count;
1001 	unsigned long ret;
1002 
1003 	/*
1004 	 * The retry count sets a maximum for the number of broadcast and
1005 	 * multicast destinations within the system.
1006 	 */
1007 	retry_count = 1024;
1008 	correlator = 0;
1009 	do {
1010 		ret = h_send_logical_lan(adapter->vdev->unit_address,
1011 					     descs[0].desc, descs[1].desc,
1012 					     descs[2].desc, descs[3].desc,
1013 					     descs[4].desc, descs[5].desc,
1014 					     correlator, &correlator, mss,
1015 					     adapter->fw_large_send_support);
1016 	} while ((ret == H_BUSY) && (retry_count--));
1017 
1018 	if (ret != H_SUCCESS && ret != H_DROPPED) {
1019 		netdev_err(adapter->netdev, "tx: h_send_logical_lan failed "
1020 			   "with rc=%ld\n", ret);
1021 		return 1;
1022 	}
1023 
1024 	return 0;
1025 }
1026 
1027 static netdev_tx_t ibmveth_start_xmit(struct sk_buff *skb,
1028 				      struct net_device *netdev)
1029 {
1030 	struct ibmveth_adapter *adapter = netdev_priv(netdev);
1031 	unsigned int desc_flags;
1032 	union ibmveth_buf_desc descs[6];
1033 	int last, i;
1034 	int force_bounce = 0;
1035 	dma_addr_t dma_addr;
1036 	unsigned long mss = 0;
1037 
1038 	/* veth doesn't handle frag_list, so linearize the skb.
1039 	 * When GRO is enabled SKB's can have frag_list.
1040 	 */
1041 	if (adapter->is_active_trunk &&
1042 	    skb_has_frag_list(skb) && __skb_linearize(skb)) {
1043 		netdev->stats.tx_dropped++;
1044 		goto out;
1045 	}
1046 
1047 	/*
1048 	 * veth handles a maximum of 6 segments including the header, so
1049 	 * we have to linearize the skb if there are more than this.
1050 	 */
1051 	if (skb_shinfo(skb)->nr_frags > 5 && __skb_linearize(skb)) {
1052 		netdev->stats.tx_dropped++;
1053 		goto out;
1054 	}
1055 
1056 	/* veth can't checksum offload UDP */
1057 	if (skb->ip_summed == CHECKSUM_PARTIAL &&
1058 	    ((skb->protocol == htons(ETH_P_IP) &&
1059 	      ip_hdr(skb)->protocol != IPPROTO_TCP) ||
1060 	     (skb->protocol == htons(ETH_P_IPV6) &&
1061 	      ipv6_hdr(skb)->nexthdr != IPPROTO_TCP)) &&
1062 	    skb_checksum_help(skb)) {
1063 
1064 		netdev_err(netdev, "tx: failed to checksum packet\n");
1065 		netdev->stats.tx_dropped++;
1066 		goto out;
1067 	}
1068 
1069 	desc_flags = IBMVETH_BUF_VALID;
1070 
1071 	if (skb->ip_summed == CHECKSUM_PARTIAL) {
1072 		unsigned char *buf = skb_transport_header(skb) +
1073 						skb->csum_offset;
1074 
1075 		desc_flags |= (IBMVETH_BUF_NO_CSUM | IBMVETH_BUF_CSUM_GOOD);
1076 
1077 		/* Need to zero out the checksum */
1078 		buf[0] = 0;
1079 		buf[1] = 0;
1080 
1081 		if (skb_is_gso(skb) && adapter->fw_large_send_support)
1082 			desc_flags |= IBMVETH_BUF_LRG_SND;
1083 	}
1084 
1085 retry_bounce:
1086 	memset(descs, 0, sizeof(descs));
1087 
1088 	/*
1089 	 * If a linear packet is below the rx threshold then
1090 	 * copy it into the static bounce buffer. This avoids the
1091 	 * cost of a TCE insert and remove.
1092 	 */
1093 	if (force_bounce || (!skb_is_nonlinear(skb) &&
1094 				(skb->len < tx_copybreak))) {
1095 		skb_copy_from_linear_data(skb, adapter->bounce_buffer,
1096 					  skb->len);
1097 
1098 		descs[0].fields.flags_len = desc_flags | skb->len;
1099 		descs[0].fields.address = adapter->bounce_buffer_dma;
1100 
1101 		if (ibmveth_send(adapter, descs, 0)) {
1102 			adapter->tx_send_failed++;
1103 			netdev->stats.tx_dropped++;
1104 		} else {
1105 			netdev->stats.tx_packets++;
1106 			netdev->stats.tx_bytes += skb->len;
1107 		}
1108 
1109 		goto out;
1110 	}
1111 
1112 	/* Map the header */
1113 	dma_addr = dma_map_single(&adapter->vdev->dev, skb->data,
1114 				  skb_headlen(skb), DMA_TO_DEVICE);
1115 	if (dma_mapping_error(&adapter->vdev->dev, dma_addr))
1116 		goto map_failed;
1117 
1118 	descs[0].fields.flags_len = desc_flags | skb_headlen(skb);
1119 	descs[0].fields.address = dma_addr;
1120 
1121 	/* Map the frags */
1122 	for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
1123 		const skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
1124 
1125 		dma_addr = skb_frag_dma_map(&adapter->vdev->dev, frag, 0,
1126 					    skb_frag_size(frag), DMA_TO_DEVICE);
1127 
1128 		if (dma_mapping_error(&adapter->vdev->dev, dma_addr))
1129 			goto map_failed_frags;
1130 
1131 		descs[i+1].fields.flags_len = desc_flags | skb_frag_size(frag);
1132 		descs[i+1].fields.address = dma_addr;
1133 	}
1134 
1135 	if (skb->ip_summed == CHECKSUM_PARTIAL && skb_is_gso(skb)) {
1136 		if (adapter->fw_large_send_support) {
1137 			mss = (unsigned long)skb_shinfo(skb)->gso_size;
1138 			adapter->tx_large_packets++;
1139 		} else if (!skb_is_gso_v6(skb)) {
1140 			/* Put -1 in the IP checksum to tell phyp it
1141 			 * is a largesend packet. Put the mss in
1142 			 * the TCP checksum.
1143 			 */
1144 			ip_hdr(skb)->check = 0xffff;
1145 			tcp_hdr(skb)->check =
1146 				cpu_to_be16(skb_shinfo(skb)->gso_size);
1147 			adapter->tx_large_packets++;
1148 		}
1149 	}
1150 
1151 	if (ibmveth_send(adapter, descs, mss)) {
1152 		adapter->tx_send_failed++;
1153 		netdev->stats.tx_dropped++;
1154 	} else {
1155 		netdev->stats.tx_packets++;
1156 		netdev->stats.tx_bytes += skb->len;
1157 	}
1158 
1159 	dma_unmap_single(&adapter->vdev->dev,
1160 			 descs[0].fields.address,
1161 			 descs[0].fields.flags_len & IBMVETH_BUF_LEN_MASK,
1162 			 DMA_TO_DEVICE);
1163 
1164 	for (i = 1; i < skb_shinfo(skb)->nr_frags + 1; i++)
1165 		dma_unmap_page(&adapter->vdev->dev, descs[i].fields.address,
1166 			       descs[i].fields.flags_len & IBMVETH_BUF_LEN_MASK,
1167 			       DMA_TO_DEVICE);
1168 
1169 out:
1170 	dev_consume_skb_any(skb);
1171 	return NETDEV_TX_OK;
1172 
1173 map_failed_frags:
1174 	last = i+1;
1175 	for (i = 0; i < last; i++)
1176 		dma_unmap_page(&adapter->vdev->dev, descs[i].fields.address,
1177 			       descs[i].fields.flags_len & IBMVETH_BUF_LEN_MASK,
1178 			       DMA_TO_DEVICE);
1179 
1180 map_failed:
1181 	if (!firmware_has_feature(FW_FEATURE_CMO))
1182 		netdev_err(netdev, "tx: unable to map xmit buffer\n");
1183 	adapter->tx_map_failed++;
1184 	if (skb_linearize(skb)) {
1185 		netdev->stats.tx_dropped++;
1186 		goto out;
1187 	}
1188 	force_bounce = 1;
1189 	goto retry_bounce;
1190 }
1191 
1192 static void ibmveth_rx_mss_helper(struct sk_buff *skb, u16 mss, int lrg_pkt)
1193 {
1194 	struct tcphdr *tcph;
1195 	int offset = 0;
1196 	int hdr_len;
1197 
1198 	/* only TCP packets will be aggregated */
1199 	if (skb->protocol == htons(ETH_P_IP)) {
1200 		struct iphdr *iph = (struct iphdr *)skb->data;
1201 
1202 		if (iph->protocol == IPPROTO_TCP) {
1203 			offset = iph->ihl * 4;
1204 			skb_shinfo(skb)->gso_type = SKB_GSO_TCPV4;
1205 		} else {
1206 			return;
1207 		}
1208 	} else if (skb->protocol == htons(ETH_P_IPV6)) {
1209 		struct ipv6hdr *iph6 = (struct ipv6hdr *)skb->data;
1210 
1211 		if (iph6->nexthdr == IPPROTO_TCP) {
1212 			offset = sizeof(struct ipv6hdr);
1213 			skb_shinfo(skb)->gso_type = SKB_GSO_TCPV6;
1214 		} else {
1215 			return;
1216 		}
1217 	} else {
1218 		return;
1219 	}
1220 	/* if mss is not set through Large Packet bit/mss in rx buffer,
1221 	 * expect that the mss will be written to the tcp header checksum.
1222 	 */
1223 	tcph = (struct tcphdr *)(skb->data + offset);
1224 	if (lrg_pkt) {
1225 		skb_shinfo(skb)->gso_size = mss;
1226 	} else if (offset) {
1227 		skb_shinfo(skb)->gso_size = ntohs(tcph->check);
1228 		tcph->check = 0;
1229 	}
1230 
1231 	if (skb_shinfo(skb)->gso_size) {
1232 		hdr_len = offset + tcph->doff * 4;
1233 		skb_shinfo(skb)->gso_segs =
1234 				DIV_ROUND_UP(skb->len - hdr_len,
1235 					     skb_shinfo(skb)->gso_size);
1236 	}
1237 }
1238 
1239 static void ibmveth_rx_csum_helper(struct sk_buff *skb,
1240 				   struct ibmveth_adapter *adapter)
1241 {
1242 	struct iphdr *iph = NULL;
1243 	struct ipv6hdr *iph6 = NULL;
1244 	__be16 skb_proto = 0;
1245 	u16 iphlen = 0;
1246 	u16 iph_proto = 0;
1247 	u16 tcphdrlen = 0;
1248 
1249 	skb_proto = be16_to_cpu(skb->protocol);
1250 
1251 	if (skb_proto == ETH_P_IP) {
1252 		iph = (struct iphdr *)skb->data;
1253 
1254 		/* If the IP checksum is not offloaded and if the packet
1255 		 *  is large send, the checksum must be rebuilt.
1256 		 */
1257 		if (iph->check == 0xffff) {
1258 			iph->check = 0;
1259 			iph->check = ip_fast_csum((unsigned char *)iph,
1260 						  iph->ihl);
1261 		}
1262 
1263 		iphlen = iph->ihl * 4;
1264 		iph_proto = iph->protocol;
1265 	} else if (skb_proto == ETH_P_IPV6) {
1266 		iph6 = (struct ipv6hdr *)skb->data;
1267 		iphlen = sizeof(struct ipv6hdr);
1268 		iph_proto = iph6->nexthdr;
1269 	}
1270 
1271 	/* In OVS environment, when a flow is not cached, specifically for a
1272 	 * new TCP connection, the first packet information is passed up
1273 	 * the user space for finding a flow. During this process, OVS computes
1274 	 * checksum on the first packet when CHECKSUM_PARTIAL flag is set.
1275 	 *
1276 	 * Given that we zeroed out TCP checksum field in transmit path
1277 	 * (refer ibmveth_start_xmit routine) as we set "no checksum bit",
1278 	 * OVS computed checksum will be incorrect w/o TCP pseudo checksum
1279 	 * in the packet. This leads to OVS dropping the packet and hence
1280 	 * TCP retransmissions are seen.
1281 	 *
1282 	 * So, re-compute TCP pseudo header checksum.
1283 	 */
1284 	if (iph_proto == IPPROTO_TCP && adapter->is_active_trunk) {
1285 		struct tcphdr *tcph = (struct tcphdr *)(skb->data + iphlen);
1286 
1287 		tcphdrlen = skb->len - iphlen;
1288 
1289 		/* Recompute TCP pseudo header checksum */
1290 		if (skb_proto == ETH_P_IP)
1291 			tcph->check = ~csum_tcpudp_magic(iph->saddr,
1292 					iph->daddr, tcphdrlen, iph_proto, 0);
1293 		else if (skb_proto == ETH_P_IPV6)
1294 			tcph->check = ~csum_ipv6_magic(&iph6->saddr,
1295 					&iph6->daddr, tcphdrlen, iph_proto, 0);
1296 
1297 		/* Setup SKB fields for checksum offload */
1298 		skb_partial_csum_set(skb, iphlen,
1299 				     offsetof(struct tcphdr, check));
1300 		skb_reset_network_header(skb);
1301 	}
1302 }
1303 
1304 static int ibmveth_poll(struct napi_struct *napi, int budget)
1305 {
1306 	struct ibmveth_adapter *adapter =
1307 			container_of(napi, struct ibmveth_adapter, napi);
1308 	struct net_device *netdev = adapter->netdev;
1309 	int frames_processed = 0;
1310 	unsigned long lpar_rc;
1311 	u16 mss = 0;
1312 
1313 restart_poll:
1314 	while (frames_processed < budget) {
1315 		if (!ibmveth_rxq_pending_buffer(adapter))
1316 			break;
1317 
1318 		smp_rmb();
1319 		if (!ibmveth_rxq_buffer_valid(adapter)) {
1320 			wmb(); /* suggested by larson1 */
1321 			adapter->rx_invalid_buffer++;
1322 			netdev_dbg(netdev, "recycling invalid buffer\n");
1323 			ibmveth_rxq_recycle_buffer(adapter);
1324 		} else {
1325 			struct sk_buff *skb, *new_skb;
1326 			int length = ibmveth_rxq_frame_length(adapter);
1327 			int offset = ibmveth_rxq_frame_offset(adapter);
1328 			int csum_good = ibmveth_rxq_csum_good(adapter);
1329 			int lrg_pkt = ibmveth_rxq_large_packet(adapter);
1330 
1331 			skb = ibmveth_rxq_get_buffer(adapter);
1332 
1333 			/* if the large packet bit is set in the rx queue
1334 			 * descriptor, the mss will be written by PHYP eight
1335 			 * bytes from the start of the rx buffer, which is
1336 			 * skb->data at this stage
1337 			 */
1338 			if (lrg_pkt) {
1339 				__be64 *rxmss = (__be64 *)(skb->data + 8);
1340 
1341 				mss = (u16)be64_to_cpu(*rxmss);
1342 			}
1343 
1344 			new_skb = NULL;
1345 			if (length < rx_copybreak)
1346 				new_skb = netdev_alloc_skb(netdev, length);
1347 
1348 			if (new_skb) {
1349 				skb_copy_to_linear_data(new_skb,
1350 							skb->data + offset,
1351 							length);
1352 				if (rx_flush)
1353 					ibmveth_flush_buffer(skb->data,
1354 						length + offset);
1355 				if (!ibmveth_rxq_recycle_buffer(adapter))
1356 					kfree_skb(skb);
1357 				skb = new_skb;
1358 			} else {
1359 				ibmveth_rxq_harvest_buffer(adapter);
1360 				skb_reserve(skb, offset);
1361 			}
1362 
1363 			skb_put(skb, length);
1364 			skb->protocol = eth_type_trans(skb, netdev);
1365 
1366 			if (csum_good) {
1367 				skb->ip_summed = CHECKSUM_UNNECESSARY;
1368 				ibmveth_rx_csum_helper(skb, adapter);
1369 			}
1370 
1371 			if (length > netdev->mtu + ETH_HLEN) {
1372 				ibmveth_rx_mss_helper(skb, mss, lrg_pkt);
1373 				adapter->rx_large_packets++;
1374 			}
1375 
1376 			napi_gro_receive(napi, skb);	/* send it up */
1377 
1378 			netdev->stats.rx_packets++;
1379 			netdev->stats.rx_bytes += length;
1380 			frames_processed++;
1381 		}
1382 	}
1383 
1384 	ibmveth_replenish_task(adapter);
1385 
1386 	if (frames_processed < budget) {
1387 		napi_complete_done(napi, frames_processed);
1388 
1389 		/* We think we are done - reenable interrupts,
1390 		 * then check once more to make sure we are done.
1391 		 */
1392 		lpar_rc = h_vio_signal(adapter->vdev->unit_address,
1393 				       VIO_IRQ_ENABLE);
1394 
1395 		BUG_ON(lpar_rc != H_SUCCESS);
1396 
1397 		if (ibmveth_rxq_pending_buffer(adapter) &&
1398 		    napi_reschedule(napi)) {
1399 			lpar_rc = h_vio_signal(adapter->vdev->unit_address,
1400 					       VIO_IRQ_DISABLE);
1401 			goto restart_poll;
1402 		}
1403 	}
1404 
1405 	return frames_processed;
1406 }
1407 
1408 static irqreturn_t ibmveth_interrupt(int irq, void *dev_instance)
1409 {
1410 	struct net_device *netdev = dev_instance;
1411 	struct ibmveth_adapter *adapter = netdev_priv(netdev);
1412 	unsigned long lpar_rc;
1413 
1414 	if (napi_schedule_prep(&adapter->napi)) {
1415 		lpar_rc = h_vio_signal(adapter->vdev->unit_address,
1416 				       VIO_IRQ_DISABLE);
1417 		BUG_ON(lpar_rc != H_SUCCESS);
1418 		__napi_schedule(&adapter->napi);
1419 	}
1420 	return IRQ_HANDLED;
1421 }
1422 
1423 static void ibmveth_set_multicast_list(struct net_device *netdev)
1424 {
1425 	struct ibmveth_adapter *adapter = netdev_priv(netdev);
1426 	unsigned long lpar_rc;
1427 
1428 	if ((netdev->flags & IFF_PROMISC) ||
1429 	    (netdev_mc_count(netdev) > adapter->mcastFilterSize)) {
1430 		lpar_rc = h_multicast_ctrl(adapter->vdev->unit_address,
1431 					   IbmVethMcastEnableRecv |
1432 					   IbmVethMcastDisableFiltering,
1433 					   0);
1434 		if (lpar_rc != H_SUCCESS) {
1435 			netdev_err(netdev, "h_multicast_ctrl rc=%ld when "
1436 				   "entering promisc mode\n", lpar_rc);
1437 		}
1438 	} else {
1439 		struct netdev_hw_addr *ha;
1440 		/* clear the filter table & disable filtering */
1441 		lpar_rc = h_multicast_ctrl(adapter->vdev->unit_address,
1442 					   IbmVethMcastEnableRecv |
1443 					   IbmVethMcastDisableFiltering |
1444 					   IbmVethMcastClearFilterTable,
1445 					   0);
1446 		if (lpar_rc != H_SUCCESS) {
1447 			netdev_err(netdev, "h_multicast_ctrl rc=%ld when "
1448 				   "attempting to clear filter table\n",
1449 				   lpar_rc);
1450 		}
1451 		/* add the addresses to the filter table */
1452 		netdev_for_each_mc_addr(ha, netdev) {
1453 			/* add the multicast address to the filter table */
1454 			u64 mcast_addr;
1455 			mcast_addr = ibmveth_encode_mac_addr(ha->addr);
1456 			lpar_rc = h_multicast_ctrl(adapter->vdev->unit_address,
1457 						   IbmVethMcastAddFilter,
1458 						   mcast_addr);
1459 			if (lpar_rc != H_SUCCESS) {
1460 				netdev_err(netdev, "h_multicast_ctrl rc=%ld "
1461 					   "when adding an entry to the filter "
1462 					   "table\n", lpar_rc);
1463 			}
1464 		}
1465 
1466 		/* re-enable filtering */
1467 		lpar_rc = h_multicast_ctrl(adapter->vdev->unit_address,
1468 					   IbmVethMcastEnableFiltering,
1469 					   0);
1470 		if (lpar_rc != H_SUCCESS) {
1471 			netdev_err(netdev, "h_multicast_ctrl rc=%ld when "
1472 				   "enabling filtering\n", lpar_rc);
1473 		}
1474 	}
1475 }
1476 
1477 static int ibmveth_change_mtu(struct net_device *dev, int new_mtu)
1478 {
1479 	struct ibmveth_adapter *adapter = netdev_priv(dev);
1480 	struct vio_dev *viodev = adapter->vdev;
1481 	int new_mtu_oh = new_mtu + IBMVETH_BUFF_OH;
1482 	int i, rc;
1483 	int need_restart = 0;
1484 
1485 	for (i = 0; i < IBMVETH_NUM_BUFF_POOLS; i++)
1486 		if (new_mtu_oh <= adapter->rx_buff_pool[i].buff_size)
1487 			break;
1488 
1489 	if (i == IBMVETH_NUM_BUFF_POOLS)
1490 		return -EINVAL;
1491 
1492 	/* Deactivate all the buffer pools so that the next loop can activate
1493 	   only the buffer pools necessary to hold the new MTU */
1494 	if (netif_running(adapter->netdev)) {
1495 		need_restart = 1;
1496 		adapter->pool_config = 1;
1497 		ibmveth_close(adapter->netdev);
1498 		adapter->pool_config = 0;
1499 	}
1500 
1501 	/* Look for an active buffer pool that can hold the new MTU */
1502 	for (i = 0; i < IBMVETH_NUM_BUFF_POOLS; i++) {
1503 		adapter->rx_buff_pool[i].active = 1;
1504 
1505 		if (new_mtu_oh <= adapter->rx_buff_pool[i].buff_size) {
1506 			dev->mtu = new_mtu;
1507 			vio_cmo_set_dev_desired(viodev,
1508 						ibmveth_get_desired_dma
1509 						(viodev));
1510 			if (need_restart) {
1511 				return ibmveth_open(adapter->netdev);
1512 			}
1513 			return 0;
1514 		}
1515 	}
1516 
1517 	if (need_restart && (rc = ibmveth_open(adapter->netdev)))
1518 		return rc;
1519 
1520 	return -EINVAL;
1521 }
1522 
1523 #ifdef CONFIG_NET_POLL_CONTROLLER
1524 static void ibmveth_poll_controller(struct net_device *dev)
1525 {
1526 	ibmveth_replenish_task(netdev_priv(dev));
1527 	ibmveth_interrupt(dev->irq, dev);
1528 }
1529 #endif
1530 
1531 /**
1532  * ibmveth_get_desired_dma - Calculate IO memory desired by the driver
1533  *
1534  * @vdev: struct vio_dev for the device whose desired IO mem is to be returned
1535  *
1536  * Return value:
1537  *	Number of bytes of IO data the driver will need to perform well.
1538  */
1539 static unsigned long ibmveth_get_desired_dma(struct vio_dev *vdev)
1540 {
1541 	struct net_device *netdev = dev_get_drvdata(&vdev->dev);
1542 	struct ibmveth_adapter *adapter;
1543 	struct iommu_table *tbl;
1544 	unsigned long ret;
1545 	int i;
1546 	int rxqentries = 1;
1547 
1548 	tbl = get_iommu_table_base(&vdev->dev);
1549 
1550 	/* netdev inits at probe time along with the structures we need below*/
1551 	if (netdev == NULL)
1552 		return IOMMU_PAGE_ALIGN(IBMVETH_IO_ENTITLEMENT_DEFAULT, tbl);
1553 
1554 	adapter = netdev_priv(netdev);
1555 
1556 	ret = IBMVETH_BUFF_LIST_SIZE + IBMVETH_FILT_LIST_SIZE;
1557 	ret += IOMMU_PAGE_ALIGN(netdev->mtu, tbl);
1558 
1559 	for (i = 0; i < IBMVETH_NUM_BUFF_POOLS; i++) {
1560 		/* add the size of the active receive buffers */
1561 		if (adapter->rx_buff_pool[i].active)
1562 			ret +=
1563 			    adapter->rx_buff_pool[i].size *
1564 			    IOMMU_PAGE_ALIGN(adapter->rx_buff_pool[i].
1565 					     buff_size, tbl);
1566 		rxqentries += adapter->rx_buff_pool[i].size;
1567 	}
1568 	/* add the size of the receive queue entries */
1569 	ret += IOMMU_PAGE_ALIGN(
1570 		rxqentries * sizeof(struct ibmveth_rx_q_entry), tbl);
1571 
1572 	return ret;
1573 }
1574 
1575 static int ibmveth_set_mac_addr(struct net_device *dev, void *p)
1576 {
1577 	struct ibmveth_adapter *adapter = netdev_priv(dev);
1578 	struct sockaddr *addr = p;
1579 	u64 mac_address;
1580 	int rc;
1581 
1582 	if (!is_valid_ether_addr(addr->sa_data))
1583 		return -EADDRNOTAVAIL;
1584 
1585 	mac_address = ibmveth_encode_mac_addr(addr->sa_data);
1586 	rc = h_change_logical_lan_mac(adapter->vdev->unit_address, mac_address);
1587 	if (rc) {
1588 		netdev_err(adapter->netdev, "h_change_logical_lan_mac failed with rc=%d\n", rc);
1589 		return rc;
1590 	}
1591 
1592 	ether_addr_copy(dev->dev_addr, addr->sa_data);
1593 
1594 	return 0;
1595 }
1596 
1597 static const struct net_device_ops ibmveth_netdev_ops = {
1598 	.ndo_open		= ibmveth_open,
1599 	.ndo_stop		= ibmveth_close,
1600 	.ndo_start_xmit		= ibmveth_start_xmit,
1601 	.ndo_set_rx_mode	= ibmveth_set_multicast_list,
1602 	.ndo_do_ioctl		= ibmveth_ioctl,
1603 	.ndo_change_mtu		= ibmveth_change_mtu,
1604 	.ndo_fix_features	= ibmveth_fix_features,
1605 	.ndo_set_features	= ibmveth_set_features,
1606 	.ndo_validate_addr	= eth_validate_addr,
1607 	.ndo_set_mac_address    = ibmveth_set_mac_addr,
1608 #ifdef CONFIG_NET_POLL_CONTROLLER
1609 	.ndo_poll_controller	= ibmveth_poll_controller,
1610 #endif
1611 };
1612 
1613 static int ibmveth_probe(struct vio_dev *dev, const struct vio_device_id *id)
1614 {
1615 	int rc, i, mac_len;
1616 	struct net_device *netdev;
1617 	struct ibmveth_adapter *adapter;
1618 	unsigned char *mac_addr_p;
1619 	unsigned int *mcastFilterSize_p;
1620 	long ret;
1621 	unsigned long ret_attr;
1622 
1623 	dev_dbg(&dev->dev, "entering ibmveth_probe for UA 0x%x\n",
1624 		dev->unit_address);
1625 
1626 	mac_addr_p = (unsigned char *)vio_get_attribute(dev, VETH_MAC_ADDR,
1627 							&mac_len);
1628 	if (!mac_addr_p) {
1629 		dev_err(&dev->dev, "Can't find VETH_MAC_ADDR attribute\n");
1630 		return -EINVAL;
1631 	}
1632 	/* Workaround for old/broken pHyp */
1633 	if (mac_len == 8)
1634 		mac_addr_p += 2;
1635 	else if (mac_len != 6) {
1636 		dev_err(&dev->dev, "VETH_MAC_ADDR attribute wrong len %d\n",
1637 			mac_len);
1638 		return -EINVAL;
1639 	}
1640 
1641 	mcastFilterSize_p = (unsigned int *)vio_get_attribute(dev,
1642 						VETH_MCAST_FILTER_SIZE, NULL);
1643 	if (!mcastFilterSize_p) {
1644 		dev_err(&dev->dev, "Can't find VETH_MCAST_FILTER_SIZE "
1645 			"attribute\n");
1646 		return -EINVAL;
1647 	}
1648 
1649 	netdev = alloc_etherdev(sizeof(struct ibmveth_adapter));
1650 
1651 	if (!netdev)
1652 		return -ENOMEM;
1653 
1654 	adapter = netdev_priv(netdev);
1655 	dev_set_drvdata(&dev->dev, netdev);
1656 
1657 	adapter->vdev = dev;
1658 	adapter->netdev = netdev;
1659 	adapter->mcastFilterSize = *mcastFilterSize_p;
1660 	adapter->pool_config = 0;
1661 
1662 	netif_napi_add(netdev, &adapter->napi, ibmveth_poll, 16);
1663 
1664 	netdev->irq = dev->irq;
1665 	netdev->netdev_ops = &ibmveth_netdev_ops;
1666 	netdev->ethtool_ops = &netdev_ethtool_ops;
1667 	SET_NETDEV_DEV(netdev, &dev->dev);
1668 	netdev->hw_features = NETIF_F_SG;
1669 	if (vio_get_attribute(dev, "ibm,illan-options", NULL) != NULL) {
1670 		netdev->hw_features |= NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM |
1671 				       NETIF_F_RXCSUM;
1672 	}
1673 
1674 	netdev->features |= netdev->hw_features;
1675 
1676 	ret = h_illan_attributes(adapter->vdev->unit_address, 0, 0, &ret_attr);
1677 
1678 	/* If running older firmware, TSO should not be enabled by default */
1679 	if (ret == H_SUCCESS && (ret_attr & IBMVETH_ILLAN_LRG_SND_SUPPORT) &&
1680 	    !old_large_send) {
1681 		netdev->hw_features |= NETIF_F_TSO | NETIF_F_TSO6;
1682 		netdev->features |= netdev->hw_features;
1683 	} else {
1684 		netdev->hw_features |= NETIF_F_TSO;
1685 	}
1686 
1687 	adapter->is_active_trunk = false;
1688 	if (ret == H_SUCCESS && (ret_attr & IBMVETH_ILLAN_ACTIVE_TRUNK)) {
1689 		adapter->is_active_trunk = true;
1690 		netdev->hw_features |= NETIF_F_FRAGLIST;
1691 		netdev->features |= NETIF_F_FRAGLIST;
1692 	}
1693 
1694 	netdev->min_mtu = IBMVETH_MIN_MTU;
1695 	netdev->max_mtu = ETH_MAX_MTU;
1696 
1697 	memcpy(netdev->dev_addr, mac_addr_p, ETH_ALEN);
1698 
1699 	if (firmware_has_feature(FW_FEATURE_CMO))
1700 		memcpy(pool_count, pool_count_cmo, sizeof(pool_count));
1701 
1702 	for (i = 0; i < IBMVETH_NUM_BUFF_POOLS; i++) {
1703 		struct kobject *kobj = &adapter->rx_buff_pool[i].kobj;
1704 		int error;
1705 
1706 		ibmveth_init_buffer_pool(&adapter->rx_buff_pool[i], i,
1707 					 pool_count[i], pool_size[i],
1708 					 pool_active[i]);
1709 		error = kobject_init_and_add(kobj, &ktype_veth_pool,
1710 					     &dev->dev.kobj, "pool%d", i);
1711 		if (!error)
1712 			kobject_uevent(kobj, KOBJ_ADD);
1713 	}
1714 
1715 	netdev_dbg(netdev, "adapter @ 0x%p\n", adapter);
1716 	netdev_dbg(netdev, "registering netdev...\n");
1717 
1718 	ibmveth_set_features(netdev, netdev->features);
1719 
1720 	rc = register_netdev(netdev);
1721 
1722 	if (rc) {
1723 		netdev_dbg(netdev, "failed to register netdev rc=%d\n", rc);
1724 		free_netdev(netdev);
1725 		return rc;
1726 	}
1727 
1728 	netdev_dbg(netdev, "registered\n");
1729 
1730 	return 0;
1731 }
1732 
1733 static int ibmveth_remove(struct vio_dev *dev)
1734 {
1735 	struct net_device *netdev = dev_get_drvdata(&dev->dev);
1736 	struct ibmveth_adapter *adapter = netdev_priv(netdev);
1737 	int i;
1738 
1739 	for (i = 0; i < IBMVETH_NUM_BUFF_POOLS; i++)
1740 		kobject_put(&adapter->rx_buff_pool[i].kobj);
1741 
1742 	unregister_netdev(netdev);
1743 
1744 	free_netdev(netdev);
1745 	dev_set_drvdata(&dev->dev, NULL);
1746 
1747 	return 0;
1748 }
1749 
1750 static struct attribute veth_active_attr;
1751 static struct attribute veth_num_attr;
1752 static struct attribute veth_size_attr;
1753 
1754 static ssize_t veth_pool_show(struct kobject *kobj,
1755 			      struct attribute *attr, char *buf)
1756 {
1757 	struct ibmveth_buff_pool *pool = container_of(kobj,
1758 						      struct ibmveth_buff_pool,
1759 						      kobj);
1760 
1761 	if (attr == &veth_active_attr)
1762 		return sprintf(buf, "%d\n", pool->active);
1763 	else if (attr == &veth_num_attr)
1764 		return sprintf(buf, "%d\n", pool->size);
1765 	else if (attr == &veth_size_attr)
1766 		return sprintf(buf, "%d\n", pool->buff_size);
1767 	return 0;
1768 }
1769 
1770 static ssize_t veth_pool_store(struct kobject *kobj, struct attribute *attr,
1771 			       const char *buf, size_t count)
1772 {
1773 	struct ibmveth_buff_pool *pool = container_of(kobj,
1774 						      struct ibmveth_buff_pool,
1775 						      kobj);
1776 	struct net_device *netdev = dev_get_drvdata(
1777 	    container_of(kobj->parent, struct device, kobj));
1778 	struct ibmveth_adapter *adapter = netdev_priv(netdev);
1779 	long value = simple_strtol(buf, NULL, 10);
1780 	long rc;
1781 
1782 	if (attr == &veth_active_attr) {
1783 		if (value && !pool->active) {
1784 			if (netif_running(netdev)) {
1785 				if (ibmveth_alloc_buffer_pool(pool)) {
1786 					netdev_err(netdev,
1787 						   "unable to alloc pool\n");
1788 					return -ENOMEM;
1789 				}
1790 				pool->active = 1;
1791 				adapter->pool_config = 1;
1792 				ibmveth_close(netdev);
1793 				adapter->pool_config = 0;
1794 				if ((rc = ibmveth_open(netdev)))
1795 					return rc;
1796 			} else {
1797 				pool->active = 1;
1798 			}
1799 		} else if (!value && pool->active) {
1800 			int mtu = netdev->mtu + IBMVETH_BUFF_OH;
1801 			int i;
1802 			/* Make sure there is a buffer pool with buffers that
1803 			   can hold a packet of the size of the MTU */
1804 			for (i = 0; i < IBMVETH_NUM_BUFF_POOLS; i++) {
1805 				if (pool == &adapter->rx_buff_pool[i])
1806 					continue;
1807 				if (!adapter->rx_buff_pool[i].active)
1808 					continue;
1809 				if (mtu <= adapter->rx_buff_pool[i].buff_size)
1810 					break;
1811 			}
1812 
1813 			if (i == IBMVETH_NUM_BUFF_POOLS) {
1814 				netdev_err(netdev, "no active pool >= MTU\n");
1815 				return -EPERM;
1816 			}
1817 
1818 			if (netif_running(netdev)) {
1819 				adapter->pool_config = 1;
1820 				ibmveth_close(netdev);
1821 				pool->active = 0;
1822 				adapter->pool_config = 0;
1823 				if ((rc = ibmveth_open(netdev)))
1824 					return rc;
1825 			}
1826 			pool->active = 0;
1827 		}
1828 	} else if (attr == &veth_num_attr) {
1829 		if (value <= 0 || value > IBMVETH_MAX_POOL_COUNT) {
1830 			return -EINVAL;
1831 		} else {
1832 			if (netif_running(netdev)) {
1833 				adapter->pool_config = 1;
1834 				ibmveth_close(netdev);
1835 				adapter->pool_config = 0;
1836 				pool->size = value;
1837 				if ((rc = ibmveth_open(netdev)))
1838 					return rc;
1839 			} else {
1840 				pool->size = value;
1841 			}
1842 		}
1843 	} else if (attr == &veth_size_attr) {
1844 		if (value <= IBMVETH_BUFF_OH || value > IBMVETH_MAX_BUF_SIZE) {
1845 			return -EINVAL;
1846 		} else {
1847 			if (netif_running(netdev)) {
1848 				adapter->pool_config = 1;
1849 				ibmveth_close(netdev);
1850 				adapter->pool_config = 0;
1851 				pool->buff_size = value;
1852 				if ((rc = ibmveth_open(netdev)))
1853 					return rc;
1854 			} else {
1855 				pool->buff_size = value;
1856 			}
1857 		}
1858 	}
1859 
1860 	/* kick the interrupt handler to allocate/deallocate pools */
1861 	ibmveth_interrupt(netdev->irq, netdev);
1862 	return count;
1863 }
1864 
1865 
1866 #define ATTR(_name, _mode)				\
1867 	struct attribute veth_##_name##_attr = {	\
1868 	.name = __stringify(_name), .mode = _mode,	\
1869 	};
1870 
1871 static ATTR(active, 0644);
1872 static ATTR(num, 0644);
1873 static ATTR(size, 0644);
1874 
1875 static struct attribute *veth_pool_attrs[] = {
1876 	&veth_active_attr,
1877 	&veth_num_attr,
1878 	&veth_size_attr,
1879 	NULL,
1880 };
1881 
1882 static const struct sysfs_ops veth_pool_ops = {
1883 	.show   = veth_pool_show,
1884 	.store  = veth_pool_store,
1885 };
1886 
1887 static struct kobj_type ktype_veth_pool = {
1888 	.release        = NULL,
1889 	.sysfs_ops      = &veth_pool_ops,
1890 	.default_attrs  = veth_pool_attrs,
1891 };
1892 
1893 static int ibmveth_resume(struct device *dev)
1894 {
1895 	struct net_device *netdev = dev_get_drvdata(dev);
1896 	ibmveth_interrupt(netdev->irq, netdev);
1897 	return 0;
1898 }
1899 
1900 static const struct vio_device_id ibmveth_device_table[] = {
1901 	{ "network", "IBM,l-lan"},
1902 	{ "", "" }
1903 };
1904 MODULE_DEVICE_TABLE(vio, ibmveth_device_table);
1905 
1906 static const struct dev_pm_ops ibmveth_pm_ops = {
1907 	.resume = ibmveth_resume
1908 };
1909 
1910 static struct vio_driver ibmveth_driver = {
1911 	.id_table	= ibmveth_device_table,
1912 	.probe		= ibmveth_probe,
1913 	.remove		= ibmveth_remove,
1914 	.get_desired_dma = ibmveth_get_desired_dma,
1915 	.name		= ibmveth_driver_name,
1916 	.pm		= &ibmveth_pm_ops,
1917 };
1918 
1919 static int __init ibmveth_module_init(void)
1920 {
1921 	printk(KERN_DEBUG "%s: %s %s\n", ibmveth_driver_name,
1922 	       ibmveth_driver_string, ibmveth_driver_version);
1923 
1924 	return vio_register_driver(&ibmveth_driver);
1925 }
1926 
1927 static void __exit ibmveth_module_exit(void)
1928 {
1929 	vio_unregister_driver(&ibmveth_driver);
1930 }
1931 
1932 module_init(ibmveth_module_init);
1933 module_exit(ibmveth_module_exit);
1934