xref: /linux/drivers/net/ethernet/ibm/ibmveth.c (revision 44f57d78)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * IBM Power Virtual Ethernet Device Driver
4  *
5  * Copyright (C) IBM Corporation, 2003, 2010
6  *
7  * Authors: Dave Larson <larson1@us.ibm.com>
8  *	    Santiago Leon <santil@linux.vnet.ibm.com>
9  *	    Brian King <brking@linux.vnet.ibm.com>
10  *	    Robert Jennings <rcj@linux.vnet.ibm.com>
11  *	    Anton Blanchard <anton@au.ibm.com>
12  */
13 
14 #include <linux/module.h>
15 #include <linux/types.h>
16 #include <linux/errno.h>
17 #include <linux/dma-mapping.h>
18 #include <linux/kernel.h>
19 #include <linux/netdevice.h>
20 #include <linux/etherdevice.h>
21 #include <linux/skbuff.h>
22 #include <linux/init.h>
23 #include <linux/interrupt.h>
24 #include <linux/mm.h>
25 #include <linux/pm.h>
26 #include <linux/ethtool.h>
27 #include <linux/in.h>
28 #include <linux/ip.h>
29 #include <linux/ipv6.h>
30 #include <linux/slab.h>
31 #include <asm/hvcall.h>
32 #include <linux/atomic.h>
33 #include <asm/vio.h>
34 #include <asm/iommu.h>
35 #include <asm/firmware.h>
36 #include <net/tcp.h>
37 #include <net/ip6_checksum.h>
38 
39 #include "ibmveth.h"
40 
41 static irqreturn_t ibmveth_interrupt(int irq, void *dev_instance);
42 static void ibmveth_rxq_harvest_buffer(struct ibmveth_adapter *adapter);
43 static unsigned long ibmveth_get_desired_dma(struct vio_dev *vdev);
44 
45 static struct kobj_type ktype_veth_pool;
46 
47 
48 static const char ibmveth_driver_name[] = "ibmveth";
49 static const char ibmveth_driver_string[] = "IBM Power Virtual Ethernet Driver";
50 #define ibmveth_driver_version "1.06"
51 
52 MODULE_AUTHOR("Santiago Leon <santil@linux.vnet.ibm.com>");
53 MODULE_DESCRIPTION("IBM Power Virtual Ethernet Driver");
54 MODULE_LICENSE("GPL");
55 MODULE_VERSION(ibmveth_driver_version);
56 
57 static unsigned int tx_copybreak __read_mostly = 128;
58 module_param(tx_copybreak, uint, 0644);
59 MODULE_PARM_DESC(tx_copybreak,
60 	"Maximum size of packet that is copied to a new buffer on transmit");
61 
62 static unsigned int rx_copybreak __read_mostly = 128;
63 module_param(rx_copybreak, uint, 0644);
64 MODULE_PARM_DESC(rx_copybreak,
65 	"Maximum size of packet that is copied to a new buffer on receive");
66 
67 static unsigned int rx_flush __read_mostly = 0;
68 module_param(rx_flush, uint, 0644);
69 MODULE_PARM_DESC(rx_flush, "Flush receive buffers before use");
70 
71 static bool old_large_send __read_mostly;
72 module_param(old_large_send, bool, 0444);
73 MODULE_PARM_DESC(old_large_send,
74 	"Use old large send method on firmware that supports the new method");
75 
76 struct ibmveth_stat {
77 	char name[ETH_GSTRING_LEN];
78 	int offset;
79 };
80 
81 #define IBMVETH_STAT_OFF(stat) offsetof(struct ibmveth_adapter, stat)
82 #define IBMVETH_GET_STAT(a, off) *((u64 *)(((unsigned long)(a)) + off))
83 
84 static struct ibmveth_stat ibmveth_stats[] = {
85 	{ "replenish_task_cycles", IBMVETH_STAT_OFF(replenish_task_cycles) },
86 	{ "replenish_no_mem", IBMVETH_STAT_OFF(replenish_no_mem) },
87 	{ "replenish_add_buff_failure",
88 			IBMVETH_STAT_OFF(replenish_add_buff_failure) },
89 	{ "replenish_add_buff_success",
90 			IBMVETH_STAT_OFF(replenish_add_buff_success) },
91 	{ "rx_invalid_buffer", IBMVETH_STAT_OFF(rx_invalid_buffer) },
92 	{ "rx_no_buffer", IBMVETH_STAT_OFF(rx_no_buffer) },
93 	{ "tx_map_failed", IBMVETH_STAT_OFF(tx_map_failed) },
94 	{ "tx_send_failed", IBMVETH_STAT_OFF(tx_send_failed) },
95 	{ "fw_enabled_ipv4_csum", IBMVETH_STAT_OFF(fw_ipv4_csum_support) },
96 	{ "fw_enabled_ipv6_csum", IBMVETH_STAT_OFF(fw_ipv6_csum_support) },
97 	{ "tx_large_packets", IBMVETH_STAT_OFF(tx_large_packets) },
98 	{ "rx_large_packets", IBMVETH_STAT_OFF(rx_large_packets) },
99 	{ "fw_enabled_large_send", IBMVETH_STAT_OFF(fw_large_send_support) }
100 };
101 
102 /* simple methods of getting data from the current rxq entry */
103 static inline u32 ibmveth_rxq_flags(struct ibmveth_adapter *adapter)
104 {
105 	return be32_to_cpu(adapter->rx_queue.queue_addr[adapter->rx_queue.index].flags_off);
106 }
107 
108 static inline int ibmveth_rxq_toggle(struct ibmveth_adapter *adapter)
109 {
110 	return (ibmveth_rxq_flags(adapter) & IBMVETH_RXQ_TOGGLE) >>
111 			IBMVETH_RXQ_TOGGLE_SHIFT;
112 }
113 
114 static inline int ibmveth_rxq_pending_buffer(struct ibmveth_adapter *adapter)
115 {
116 	return ibmveth_rxq_toggle(adapter) == adapter->rx_queue.toggle;
117 }
118 
119 static inline int ibmveth_rxq_buffer_valid(struct ibmveth_adapter *adapter)
120 {
121 	return ibmveth_rxq_flags(adapter) & IBMVETH_RXQ_VALID;
122 }
123 
124 static inline int ibmveth_rxq_frame_offset(struct ibmveth_adapter *adapter)
125 {
126 	return ibmveth_rxq_flags(adapter) & IBMVETH_RXQ_OFF_MASK;
127 }
128 
129 static inline int ibmveth_rxq_large_packet(struct ibmveth_adapter *adapter)
130 {
131 	return ibmveth_rxq_flags(adapter) & IBMVETH_RXQ_LRG_PKT;
132 }
133 
134 static inline int ibmveth_rxq_frame_length(struct ibmveth_adapter *adapter)
135 {
136 	return be32_to_cpu(adapter->rx_queue.queue_addr[adapter->rx_queue.index].length);
137 }
138 
139 static inline int ibmveth_rxq_csum_good(struct ibmveth_adapter *adapter)
140 {
141 	return ibmveth_rxq_flags(adapter) & IBMVETH_RXQ_CSUM_GOOD;
142 }
143 
144 /* setup the initial settings for a buffer pool */
145 static void ibmveth_init_buffer_pool(struct ibmveth_buff_pool *pool,
146 				     u32 pool_index, u32 pool_size,
147 				     u32 buff_size, u32 pool_active)
148 {
149 	pool->size = pool_size;
150 	pool->index = pool_index;
151 	pool->buff_size = buff_size;
152 	pool->threshold = pool_size * 7 / 8;
153 	pool->active = pool_active;
154 }
155 
156 /* allocate and setup an buffer pool - called during open */
157 static int ibmveth_alloc_buffer_pool(struct ibmveth_buff_pool *pool)
158 {
159 	int i;
160 
161 	pool->free_map = kmalloc_array(pool->size, sizeof(u16), GFP_KERNEL);
162 
163 	if (!pool->free_map)
164 		return -1;
165 
166 	pool->dma_addr = kcalloc(pool->size, sizeof(dma_addr_t), GFP_KERNEL);
167 	if (!pool->dma_addr) {
168 		kfree(pool->free_map);
169 		pool->free_map = NULL;
170 		return -1;
171 	}
172 
173 	pool->skbuff = kcalloc(pool->size, sizeof(void *), GFP_KERNEL);
174 
175 	if (!pool->skbuff) {
176 		kfree(pool->dma_addr);
177 		pool->dma_addr = NULL;
178 
179 		kfree(pool->free_map);
180 		pool->free_map = NULL;
181 		return -1;
182 	}
183 
184 	for (i = 0; i < pool->size; ++i)
185 		pool->free_map[i] = i;
186 
187 	atomic_set(&pool->available, 0);
188 	pool->producer_index = 0;
189 	pool->consumer_index = 0;
190 
191 	return 0;
192 }
193 
194 static inline void ibmveth_flush_buffer(void *addr, unsigned long length)
195 {
196 	unsigned long offset;
197 
198 	for (offset = 0; offset < length; offset += SMP_CACHE_BYTES)
199 		asm("dcbfl %0,%1" :: "b" (addr), "r" (offset));
200 }
201 
202 /* replenish the buffers for a pool.  note that we don't need to
203  * skb_reserve these since they are used for incoming...
204  */
205 static void ibmveth_replenish_buffer_pool(struct ibmveth_adapter *adapter,
206 					  struct ibmveth_buff_pool *pool)
207 {
208 	u32 i;
209 	u32 count = pool->size - atomic_read(&pool->available);
210 	u32 buffers_added = 0;
211 	struct sk_buff *skb;
212 	unsigned int free_index, index;
213 	u64 correlator;
214 	unsigned long lpar_rc;
215 	dma_addr_t dma_addr;
216 
217 	mb();
218 
219 	for (i = 0; i < count; ++i) {
220 		union ibmveth_buf_desc desc;
221 
222 		skb = netdev_alloc_skb(adapter->netdev, pool->buff_size);
223 
224 		if (!skb) {
225 			netdev_dbg(adapter->netdev,
226 				   "replenish: unable to allocate skb\n");
227 			adapter->replenish_no_mem++;
228 			break;
229 		}
230 
231 		free_index = pool->consumer_index;
232 		pool->consumer_index++;
233 		if (pool->consumer_index >= pool->size)
234 			pool->consumer_index = 0;
235 		index = pool->free_map[free_index];
236 
237 		BUG_ON(index == IBM_VETH_INVALID_MAP);
238 		BUG_ON(pool->skbuff[index] != NULL);
239 
240 		dma_addr = dma_map_single(&adapter->vdev->dev, skb->data,
241 				pool->buff_size, DMA_FROM_DEVICE);
242 
243 		if (dma_mapping_error(&adapter->vdev->dev, dma_addr))
244 			goto failure;
245 
246 		pool->free_map[free_index] = IBM_VETH_INVALID_MAP;
247 		pool->dma_addr[index] = dma_addr;
248 		pool->skbuff[index] = skb;
249 
250 		correlator = ((u64)pool->index << 32) | index;
251 		*(u64 *)skb->data = correlator;
252 
253 		desc.fields.flags_len = IBMVETH_BUF_VALID | pool->buff_size;
254 		desc.fields.address = dma_addr;
255 
256 		if (rx_flush) {
257 			unsigned int len = min(pool->buff_size,
258 						adapter->netdev->mtu +
259 						IBMVETH_BUFF_OH);
260 			ibmveth_flush_buffer(skb->data, len);
261 		}
262 		lpar_rc = h_add_logical_lan_buffer(adapter->vdev->unit_address,
263 						   desc.desc);
264 
265 		if (lpar_rc != H_SUCCESS) {
266 			goto failure;
267 		} else {
268 			buffers_added++;
269 			adapter->replenish_add_buff_success++;
270 		}
271 	}
272 
273 	mb();
274 	atomic_add(buffers_added, &(pool->available));
275 	return;
276 
277 failure:
278 	pool->free_map[free_index] = index;
279 	pool->skbuff[index] = NULL;
280 	if (pool->consumer_index == 0)
281 		pool->consumer_index = pool->size - 1;
282 	else
283 		pool->consumer_index--;
284 	if (!dma_mapping_error(&adapter->vdev->dev, dma_addr))
285 		dma_unmap_single(&adapter->vdev->dev,
286 		                 pool->dma_addr[index], pool->buff_size,
287 		                 DMA_FROM_DEVICE);
288 	dev_kfree_skb_any(skb);
289 	adapter->replenish_add_buff_failure++;
290 
291 	mb();
292 	atomic_add(buffers_added, &(pool->available));
293 }
294 
295 /*
296  * The final 8 bytes of the buffer list is a counter of frames dropped
297  * because there was not a buffer in the buffer list capable of holding
298  * the frame.
299  */
300 static void ibmveth_update_rx_no_buffer(struct ibmveth_adapter *adapter)
301 {
302 	__be64 *p = adapter->buffer_list_addr + 4096 - 8;
303 
304 	adapter->rx_no_buffer = be64_to_cpup(p);
305 }
306 
307 /* replenish routine */
308 static void ibmveth_replenish_task(struct ibmveth_adapter *adapter)
309 {
310 	int i;
311 
312 	adapter->replenish_task_cycles++;
313 
314 	for (i = (IBMVETH_NUM_BUFF_POOLS - 1); i >= 0; i--) {
315 		struct ibmveth_buff_pool *pool = &adapter->rx_buff_pool[i];
316 
317 		if (pool->active &&
318 		    (atomic_read(&pool->available) < pool->threshold))
319 			ibmveth_replenish_buffer_pool(adapter, pool);
320 	}
321 
322 	ibmveth_update_rx_no_buffer(adapter);
323 }
324 
325 /* empty and free ana buffer pool - also used to do cleanup in error paths */
326 static void ibmveth_free_buffer_pool(struct ibmveth_adapter *adapter,
327 				     struct ibmveth_buff_pool *pool)
328 {
329 	int i;
330 
331 	kfree(pool->free_map);
332 	pool->free_map = NULL;
333 
334 	if (pool->skbuff && pool->dma_addr) {
335 		for (i = 0; i < pool->size; ++i) {
336 			struct sk_buff *skb = pool->skbuff[i];
337 			if (skb) {
338 				dma_unmap_single(&adapter->vdev->dev,
339 						 pool->dma_addr[i],
340 						 pool->buff_size,
341 						 DMA_FROM_DEVICE);
342 				dev_kfree_skb_any(skb);
343 				pool->skbuff[i] = NULL;
344 			}
345 		}
346 	}
347 
348 	if (pool->dma_addr) {
349 		kfree(pool->dma_addr);
350 		pool->dma_addr = NULL;
351 	}
352 
353 	if (pool->skbuff) {
354 		kfree(pool->skbuff);
355 		pool->skbuff = NULL;
356 	}
357 }
358 
359 /* remove a buffer from a pool */
360 static void ibmveth_remove_buffer_from_pool(struct ibmveth_adapter *adapter,
361 					    u64 correlator)
362 {
363 	unsigned int pool  = correlator >> 32;
364 	unsigned int index = correlator & 0xffffffffUL;
365 	unsigned int free_index;
366 	struct sk_buff *skb;
367 
368 	BUG_ON(pool >= IBMVETH_NUM_BUFF_POOLS);
369 	BUG_ON(index >= adapter->rx_buff_pool[pool].size);
370 
371 	skb = adapter->rx_buff_pool[pool].skbuff[index];
372 
373 	BUG_ON(skb == NULL);
374 
375 	adapter->rx_buff_pool[pool].skbuff[index] = NULL;
376 
377 	dma_unmap_single(&adapter->vdev->dev,
378 			 adapter->rx_buff_pool[pool].dma_addr[index],
379 			 adapter->rx_buff_pool[pool].buff_size,
380 			 DMA_FROM_DEVICE);
381 
382 	free_index = adapter->rx_buff_pool[pool].producer_index;
383 	adapter->rx_buff_pool[pool].producer_index++;
384 	if (adapter->rx_buff_pool[pool].producer_index >=
385 	    adapter->rx_buff_pool[pool].size)
386 		adapter->rx_buff_pool[pool].producer_index = 0;
387 	adapter->rx_buff_pool[pool].free_map[free_index] = index;
388 
389 	mb();
390 
391 	atomic_dec(&(adapter->rx_buff_pool[pool].available));
392 }
393 
394 /* get the current buffer on the rx queue */
395 static inline struct sk_buff *ibmveth_rxq_get_buffer(struct ibmveth_adapter *adapter)
396 {
397 	u64 correlator = adapter->rx_queue.queue_addr[adapter->rx_queue.index].correlator;
398 	unsigned int pool = correlator >> 32;
399 	unsigned int index = correlator & 0xffffffffUL;
400 
401 	BUG_ON(pool >= IBMVETH_NUM_BUFF_POOLS);
402 	BUG_ON(index >= adapter->rx_buff_pool[pool].size);
403 
404 	return adapter->rx_buff_pool[pool].skbuff[index];
405 }
406 
407 /* recycle the current buffer on the rx queue */
408 static int ibmveth_rxq_recycle_buffer(struct ibmveth_adapter *adapter)
409 {
410 	u32 q_index = adapter->rx_queue.index;
411 	u64 correlator = adapter->rx_queue.queue_addr[q_index].correlator;
412 	unsigned int pool = correlator >> 32;
413 	unsigned int index = correlator & 0xffffffffUL;
414 	union ibmveth_buf_desc desc;
415 	unsigned long lpar_rc;
416 	int ret = 1;
417 
418 	BUG_ON(pool >= IBMVETH_NUM_BUFF_POOLS);
419 	BUG_ON(index >= adapter->rx_buff_pool[pool].size);
420 
421 	if (!adapter->rx_buff_pool[pool].active) {
422 		ibmveth_rxq_harvest_buffer(adapter);
423 		ibmveth_free_buffer_pool(adapter, &adapter->rx_buff_pool[pool]);
424 		goto out;
425 	}
426 
427 	desc.fields.flags_len = IBMVETH_BUF_VALID |
428 		adapter->rx_buff_pool[pool].buff_size;
429 	desc.fields.address = adapter->rx_buff_pool[pool].dma_addr[index];
430 
431 	lpar_rc = h_add_logical_lan_buffer(adapter->vdev->unit_address, desc.desc);
432 
433 	if (lpar_rc != H_SUCCESS) {
434 		netdev_dbg(adapter->netdev, "h_add_logical_lan_buffer failed "
435 			   "during recycle rc=%ld", lpar_rc);
436 		ibmveth_remove_buffer_from_pool(adapter, adapter->rx_queue.queue_addr[adapter->rx_queue.index].correlator);
437 		ret = 0;
438 	}
439 
440 	if (++adapter->rx_queue.index == adapter->rx_queue.num_slots) {
441 		adapter->rx_queue.index = 0;
442 		adapter->rx_queue.toggle = !adapter->rx_queue.toggle;
443 	}
444 
445 out:
446 	return ret;
447 }
448 
449 static void ibmveth_rxq_harvest_buffer(struct ibmveth_adapter *adapter)
450 {
451 	ibmveth_remove_buffer_from_pool(adapter, adapter->rx_queue.queue_addr[adapter->rx_queue.index].correlator);
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 
459 static int ibmveth_register_logical_lan(struct ibmveth_adapter *adapter,
460         union ibmveth_buf_desc rxq_desc, u64 mac_address)
461 {
462 	int rc, try_again = 1;
463 
464 	/*
465 	 * After a kexec the adapter will still be open, so our attempt to
466 	 * open it will fail. So if we get a failure we free the adapter and
467 	 * try again, but only once.
468 	 */
469 retry:
470 	rc = h_register_logical_lan(adapter->vdev->unit_address,
471 				    adapter->buffer_list_dma, rxq_desc.desc,
472 				    adapter->filter_list_dma, mac_address);
473 
474 	if (rc != H_SUCCESS && try_again) {
475 		do {
476 			rc = h_free_logical_lan(adapter->vdev->unit_address);
477 		} while (H_IS_LONG_BUSY(rc) || (rc == H_BUSY));
478 
479 		try_again = 0;
480 		goto retry;
481 	}
482 
483 	return rc;
484 }
485 
486 static u64 ibmveth_encode_mac_addr(u8 *mac)
487 {
488 	int i;
489 	u64 encoded = 0;
490 
491 	for (i = 0; i < ETH_ALEN; i++)
492 		encoded = (encoded << 8) | mac[i];
493 
494 	return encoded;
495 }
496 
497 static int ibmveth_open(struct net_device *netdev)
498 {
499 	struct ibmveth_adapter *adapter = netdev_priv(netdev);
500 	u64 mac_address;
501 	int rxq_entries = 1;
502 	unsigned long lpar_rc;
503 	int rc;
504 	union ibmveth_buf_desc rxq_desc;
505 	int i;
506 	struct device *dev;
507 
508 	netdev_dbg(netdev, "open starting\n");
509 
510 	napi_enable(&adapter->napi);
511 
512 	for(i = 0; i < IBMVETH_NUM_BUFF_POOLS; i++)
513 		rxq_entries += adapter->rx_buff_pool[i].size;
514 
515 	rc = -ENOMEM;
516 	adapter->buffer_list_addr = (void*) get_zeroed_page(GFP_KERNEL);
517 	if (!adapter->buffer_list_addr) {
518 		netdev_err(netdev, "unable to allocate list pages\n");
519 		goto out;
520 	}
521 
522 	adapter->filter_list_addr = (void*) get_zeroed_page(GFP_KERNEL);
523 	if (!adapter->filter_list_addr) {
524 		netdev_err(netdev, "unable to allocate filter pages\n");
525 		goto out_free_buffer_list;
526 	}
527 
528 	dev = &adapter->vdev->dev;
529 
530 	adapter->rx_queue.queue_len = sizeof(struct ibmveth_rx_q_entry) *
531 						rxq_entries;
532 	adapter->rx_queue.queue_addr =
533 		dma_alloc_coherent(dev, adapter->rx_queue.queue_len,
534 				   &adapter->rx_queue.queue_dma, GFP_KERNEL);
535 	if (!adapter->rx_queue.queue_addr)
536 		goto out_free_filter_list;
537 
538 	adapter->buffer_list_dma = dma_map_single(dev,
539 			adapter->buffer_list_addr, 4096, DMA_BIDIRECTIONAL);
540 	if (dma_mapping_error(dev, adapter->buffer_list_dma)) {
541 		netdev_err(netdev, "unable to map buffer list pages\n");
542 		goto out_free_queue_mem;
543 	}
544 
545 	adapter->filter_list_dma = dma_map_single(dev,
546 			adapter->filter_list_addr, 4096, DMA_BIDIRECTIONAL);
547 	if (dma_mapping_error(dev, adapter->filter_list_dma)) {
548 		netdev_err(netdev, "unable to map filter list pages\n");
549 		goto out_unmap_buffer_list;
550 	}
551 
552 	adapter->rx_queue.index = 0;
553 	adapter->rx_queue.num_slots = rxq_entries;
554 	adapter->rx_queue.toggle = 1;
555 
556 	mac_address = ibmveth_encode_mac_addr(netdev->dev_addr);
557 
558 	rxq_desc.fields.flags_len = IBMVETH_BUF_VALID |
559 					adapter->rx_queue.queue_len;
560 	rxq_desc.fields.address = adapter->rx_queue.queue_dma;
561 
562 	netdev_dbg(netdev, "buffer list @ 0x%p\n", adapter->buffer_list_addr);
563 	netdev_dbg(netdev, "filter list @ 0x%p\n", adapter->filter_list_addr);
564 	netdev_dbg(netdev, "receive q   @ 0x%p\n", adapter->rx_queue.queue_addr);
565 
566 	h_vio_signal(adapter->vdev->unit_address, VIO_IRQ_DISABLE);
567 
568 	lpar_rc = ibmveth_register_logical_lan(adapter, rxq_desc, mac_address);
569 
570 	if (lpar_rc != H_SUCCESS) {
571 		netdev_err(netdev, "h_register_logical_lan failed with %ld\n",
572 			   lpar_rc);
573 		netdev_err(netdev, "buffer TCE:0x%llx filter TCE:0x%llx rxq "
574 			   "desc:0x%llx MAC:0x%llx\n",
575 				     adapter->buffer_list_dma,
576 				     adapter->filter_list_dma,
577 				     rxq_desc.desc,
578 				     mac_address);
579 		rc = -ENONET;
580 		goto out_unmap_filter_list;
581 	}
582 
583 	for (i = 0; i < IBMVETH_NUM_BUFF_POOLS; i++) {
584 		if (!adapter->rx_buff_pool[i].active)
585 			continue;
586 		if (ibmveth_alloc_buffer_pool(&adapter->rx_buff_pool[i])) {
587 			netdev_err(netdev, "unable to alloc pool\n");
588 			adapter->rx_buff_pool[i].active = 0;
589 			rc = -ENOMEM;
590 			goto out_free_buffer_pools;
591 		}
592 	}
593 
594 	netdev_dbg(netdev, "registering irq 0x%x\n", netdev->irq);
595 	rc = request_irq(netdev->irq, ibmveth_interrupt, 0, netdev->name,
596 			 netdev);
597 	if (rc != 0) {
598 		netdev_err(netdev, "unable to request irq 0x%x, rc %d\n",
599 			   netdev->irq, rc);
600 		do {
601 			lpar_rc = h_free_logical_lan(adapter->vdev->unit_address);
602 		} while (H_IS_LONG_BUSY(lpar_rc) || (lpar_rc == H_BUSY));
603 
604 		goto out_free_buffer_pools;
605 	}
606 
607 	rc = -ENOMEM;
608 	adapter->bounce_buffer =
609 	    kmalloc(netdev->mtu + IBMVETH_BUFF_OH, GFP_KERNEL);
610 	if (!adapter->bounce_buffer)
611 		goto out_free_irq;
612 
613 	adapter->bounce_buffer_dma =
614 	    dma_map_single(&adapter->vdev->dev, adapter->bounce_buffer,
615 			   netdev->mtu + IBMVETH_BUFF_OH, DMA_BIDIRECTIONAL);
616 	if (dma_mapping_error(dev, adapter->bounce_buffer_dma)) {
617 		netdev_err(netdev, "unable to map bounce buffer\n");
618 		goto out_free_bounce_buffer;
619 	}
620 
621 	netdev_dbg(netdev, "initial replenish cycle\n");
622 	ibmveth_interrupt(netdev->irq, netdev);
623 
624 	netif_start_queue(netdev);
625 
626 	netdev_dbg(netdev, "open complete\n");
627 
628 	return 0;
629 
630 out_free_bounce_buffer:
631 	kfree(adapter->bounce_buffer);
632 out_free_irq:
633 	free_irq(netdev->irq, netdev);
634 out_free_buffer_pools:
635 	while (--i >= 0) {
636 		if (adapter->rx_buff_pool[i].active)
637 			ibmveth_free_buffer_pool(adapter,
638 						 &adapter->rx_buff_pool[i]);
639 	}
640 out_unmap_filter_list:
641 	dma_unmap_single(dev, adapter->filter_list_dma, 4096,
642 			 DMA_BIDIRECTIONAL);
643 out_unmap_buffer_list:
644 	dma_unmap_single(dev, adapter->buffer_list_dma, 4096,
645 			 DMA_BIDIRECTIONAL);
646 out_free_queue_mem:
647 	dma_free_coherent(dev, adapter->rx_queue.queue_len,
648 			  adapter->rx_queue.queue_addr,
649 			  adapter->rx_queue.queue_dma);
650 out_free_filter_list:
651 	free_page((unsigned long)adapter->filter_list_addr);
652 out_free_buffer_list:
653 	free_page((unsigned long)adapter->buffer_list_addr);
654 out:
655 	napi_disable(&adapter->napi);
656 	return rc;
657 }
658 
659 static int ibmveth_close(struct net_device *netdev)
660 {
661 	struct ibmveth_adapter *adapter = netdev_priv(netdev);
662 	struct device *dev = &adapter->vdev->dev;
663 	long lpar_rc;
664 	int i;
665 
666 	netdev_dbg(netdev, "close starting\n");
667 
668 	napi_disable(&adapter->napi);
669 
670 	if (!adapter->pool_config)
671 		netif_stop_queue(netdev);
672 
673 	h_vio_signal(adapter->vdev->unit_address, VIO_IRQ_DISABLE);
674 
675 	do {
676 		lpar_rc = h_free_logical_lan(adapter->vdev->unit_address);
677 	} while (H_IS_LONG_BUSY(lpar_rc) || (lpar_rc == H_BUSY));
678 
679 	if (lpar_rc != H_SUCCESS) {
680 		netdev_err(netdev, "h_free_logical_lan failed with %lx, "
681 			   "continuing with close\n", lpar_rc);
682 	}
683 
684 	free_irq(netdev->irq, netdev);
685 
686 	ibmveth_update_rx_no_buffer(adapter);
687 
688 	dma_unmap_single(dev, adapter->buffer_list_dma, 4096,
689 			 DMA_BIDIRECTIONAL);
690 	free_page((unsigned long)adapter->buffer_list_addr);
691 
692 	dma_unmap_single(dev, adapter->filter_list_dma, 4096,
693 			 DMA_BIDIRECTIONAL);
694 	free_page((unsigned long)adapter->filter_list_addr);
695 
696 	dma_free_coherent(dev, adapter->rx_queue.queue_len,
697 			  adapter->rx_queue.queue_addr,
698 			  adapter->rx_queue.queue_dma);
699 
700 	for (i = 0; i < IBMVETH_NUM_BUFF_POOLS; i++)
701 		if (adapter->rx_buff_pool[i].active)
702 			ibmveth_free_buffer_pool(adapter,
703 						 &adapter->rx_buff_pool[i]);
704 
705 	dma_unmap_single(&adapter->vdev->dev, adapter->bounce_buffer_dma,
706 			 adapter->netdev->mtu + IBMVETH_BUFF_OH,
707 			 DMA_BIDIRECTIONAL);
708 	kfree(adapter->bounce_buffer);
709 
710 	netdev_dbg(netdev, "close complete\n");
711 
712 	return 0;
713 }
714 
715 static int netdev_get_link_ksettings(struct net_device *dev,
716 				     struct ethtool_link_ksettings *cmd)
717 {
718 	u32 supported, advertising;
719 
720 	supported = (SUPPORTED_1000baseT_Full | SUPPORTED_Autoneg |
721 				SUPPORTED_FIBRE);
722 	advertising = (ADVERTISED_1000baseT_Full | ADVERTISED_Autoneg |
723 				ADVERTISED_FIBRE);
724 	cmd->base.speed = SPEED_1000;
725 	cmd->base.duplex = DUPLEX_FULL;
726 	cmd->base.port = PORT_FIBRE;
727 	cmd->base.phy_address = 0;
728 	cmd->base.autoneg = AUTONEG_ENABLE;
729 
730 	ethtool_convert_legacy_u32_to_link_mode(cmd->link_modes.supported,
731 						supported);
732 	ethtool_convert_legacy_u32_to_link_mode(cmd->link_modes.advertising,
733 						advertising);
734 
735 	return 0;
736 }
737 
738 static void netdev_get_drvinfo(struct net_device *dev,
739 			       struct ethtool_drvinfo *info)
740 {
741 	strlcpy(info->driver, ibmveth_driver_name, sizeof(info->driver));
742 	strlcpy(info->version, ibmveth_driver_version, sizeof(info->version));
743 }
744 
745 static netdev_features_t ibmveth_fix_features(struct net_device *dev,
746 	netdev_features_t features)
747 {
748 	/*
749 	 * Since the ibmveth firmware interface does not have the
750 	 * concept of separate tx/rx checksum offload enable, if rx
751 	 * checksum is disabled we also have to disable tx checksum
752 	 * offload. Once we disable rx checksum offload, we are no
753 	 * longer allowed to send tx buffers that are not properly
754 	 * checksummed.
755 	 */
756 
757 	if (!(features & NETIF_F_RXCSUM))
758 		features &= ~NETIF_F_CSUM_MASK;
759 
760 	return features;
761 }
762 
763 static int ibmveth_set_csum_offload(struct net_device *dev, u32 data)
764 {
765 	struct ibmveth_adapter *adapter = netdev_priv(dev);
766 	unsigned long set_attr, clr_attr, ret_attr;
767 	unsigned long set_attr6, clr_attr6;
768 	long ret, ret4, ret6;
769 	int rc1 = 0, rc2 = 0;
770 	int restart = 0;
771 
772 	if (netif_running(dev)) {
773 		restart = 1;
774 		adapter->pool_config = 1;
775 		ibmveth_close(dev);
776 		adapter->pool_config = 0;
777 	}
778 
779 	set_attr = 0;
780 	clr_attr = 0;
781 	set_attr6 = 0;
782 	clr_attr6 = 0;
783 
784 	if (data) {
785 		set_attr = IBMVETH_ILLAN_IPV4_TCP_CSUM;
786 		set_attr6 = IBMVETH_ILLAN_IPV6_TCP_CSUM;
787 	} else {
788 		clr_attr = IBMVETH_ILLAN_IPV4_TCP_CSUM;
789 		clr_attr6 = IBMVETH_ILLAN_IPV6_TCP_CSUM;
790 	}
791 
792 	ret = h_illan_attributes(adapter->vdev->unit_address, 0, 0, &ret_attr);
793 
794 	if (ret == H_SUCCESS &&
795 	    (ret_attr & IBMVETH_ILLAN_PADDED_PKT_CSUM)) {
796 		ret4 = h_illan_attributes(adapter->vdev->unit_address, clr_attr,
797 					 set_attr, &ret_attr);
798 
799 		if (ret4 != H_SUCCESS) {
800 			netdev_err(dev, "unable to change IPv4 checksum "
801 					"offload settings. %d rc=%ld\n",
802 					data, ret4);
803 
804 			h_illan_attributes(adapter->vdev->unit_address,
805 					   set_attr, clr_attr, &ret_attr);
806 
807 			if (data == 1)
808 				dev->features &= ~NETIF_F_IP_CSUM;
809 
810 		} else {
811 			adapter->fw_ipv4_csum_support = data;
812 		}
813 
814 		ret6 = h_illan_attributes(adapter->vdev->unit_address,
815 					 clr_attr6, set_attr6, &ret_attr);
816 
817 		if (ret6 != H_SUCCESS) {
818 			netdev_err(dev, "unable to change IPv6 checksum "
819 					"offload settings. %d rc=%ld\n",
820 					data, ret6);
821 
822 			h_illan_attributes(adapter->vdev->unit_address,
823 					   set_attr6, clr_attr6, &ret_attr);
824 
825 			if (data == 1)
826 				dev->features &= ~NETIF_F_IPV6_CSUM;
827 
828 		} else
829 			adapter->fw_ipv6_csum_support = data;
830 
831 		if (ret4 == H_SUCCESS || ret6 == H_SUCCESS)
832 			adapter->rx_csum = data;
833 		else
834 			rc1 = -EIO;
835 	} else {
836 		rc1 = -EIO;
837 		netdev_err(dev, "unable to change checksum offload settings."
838 				     " %d rc=%ld ret_attr=%lx\n", data, ret,
839 				     ret_attr);
840 	}
841 
842 	if (restart)
843 		rc2 = ibmveth_open(dev);
844 
845 	return rc1 ? rc1 : rc2;
846 }
847 
848 static int ibmveth_set_tso(struct net_device *dev, u32 data)
849 {
850 	struct ibmveth_adapter *adapter = netdev_priv(dev);
851 	unsigned long set_attr, clr_attr, ret_attr;
852 	long ret1, ret2;
853 	int rc1 = 0, rc2 = 0;
854 	int restart = 0;
855 
856 	if (netif_running(dev)) {
857 		restart = 1;
858 		adapter->pool_config = 1;
859 		ibmveth_close(dev);
860 		adapter->pool_config = 0;
861 	}
862 
863 	set_attr = 0;
864 	clr_attr = 0;
865 
866 	if (data)
867 		set_attr = IBMVETH_ILLAN_LRG_SR_ENABLED;
868 	else
869 		clr_attr = IBMVETH_ILLAN_LRG_SR_ENABLED;
870 
871 	ret1 = h_illan_attributes(adapter->vdev->unit_address, 0, 0, &ret_attr);
872 
873 	if (ret1 == H_SUCCESS && (ret_attr & IBMVETH_ILLAN_LRG_SND_SUPPORT) &&
874 	    !old_large_send) {
875 		ret2 = h_illan_attributes(adapter->vdev->unit_address, clr_attr,
876 					  set_attr, &ret_attr);
877 
878 		if (ret2 != H_SUCCESS) {
879 			netdev_err(dev, "unable to change tso settings. %d rc=%ld\n",
880 				   data, ret2);
881 
882 			h_illan_attributes(adapter->vdev->unit_address,
883 					   set_attr, clr_attr, &ret_attr);
884 
885 			if (data == 1)
886 				dev->features &= ~(NETIF_F_TSO | NETIF_F_TSO6);
887 			rc1 = -EIO;
888 
889 		} else {
890 			adapter->fw_large_send_support = data;
891 			adapter->large_send = data;
892 		}
893 	} else {
894 		/* Older firmware version of large send offload does not
895 		 * support tcp6/ipv6
896 		 */
897 		if (data == 1) {
898 			dev->features &= ~NETIF_F_TSO6;
899 			netdev_info(dev, "TSO feature requires all partitions to have updated driver");
900 		}
901 		adapter->large_send = data;
902 	}
903 
904 	if (restart)
905 		rc2 = ibmveth_open(dev);
906 
907 	return rc1 ? rc1 : rc2;
908 }
909 
910 static int ibmveth_set_features(struct net_device *dev,
911 	netdev_features_t features)
912 {
913 	struct ibmveth_adapter *adapter = netdev_priv(dev);
914 	int rx_csum = !!(features & NETIF_F_RXCSUM);
915 	int large_send = !!(features & (NETIF_F_TSO | NETIF_F_TSO6));
916 	int rc1 = 0, rc2 = 0;
917 
918 	if (rx_csum != adapter->rx_csum) {
919 		rc1 = ibmveth_set_csum_offload(dev, rx_csum);
920 		if (rc1 && !adapter->rx_csum)
921 			dev->features =
922 				features & ~(NETIF_F_CSUM_MASK |
923 					     NETIF_F_RXCSUM);
924 	}
925 
926 	if (large_send != adapter->large_send) {
927 		rc2 = ibmveth_set_tso(dev, large_send);
928 		if (rc2 && !adapter->large_send)
929 			dev->features =
930 				features & ~(NETIF_F_TSO | NETIF_F_TSO6);
931 	}
932 
933 	return rc1 ? rc1 : rc2;
934 }
935 
936 static void ibmveth_get_strings(struct net_device *dev, u32 stringset, u8 *data)
937 {
938 	int i;
939 
940 	if (stringset != ETH_SS_STATS)
941 		return;
942 
943 	for (i = 0; i < ARRAY_SIZE(ibmveth_stats); i++, data += ETH_GSTRING_LEN)
944 		memcpy(data, ibmveth_stats[i].name, ETH_GSTRING_LEN);
945 }
946 
947 static int ibmveth_get_sset_count(struct net_device *dev, int sset)
948 {
949 	switch (sset) {
950 	case ETH_SS_STATS:
951 		return ARRAY_SIZE(ibmveth_stats);
952 	default:
953 		return -EOPNOTSUPP;
954 	}
955 }
956 
957 static void ibmveth_get_ethtool_stats(struct net_device *dev,
958 				      struct ethtool_stats *stats, u64 *data)
959 {
960 	int i;
961 	struct ibmveth_adapter *adapter = netdev_priv(dev);
962 
963 	for (i = 0; i < ARRAY_SIZE(ibmveth_stats); i++)
964 		data[i] = IBMVETH_GET_STAT(adapter, ibmveth_stats[i].offset);
965 }
966 
967 static const struct ethtool_ops netdev_ethtool_ops = {
968 	.get_drvinfo		= netdev_get_drvinfo,
969 	.get_link		= ethtool_op_get_link,
970 	.get_strings		= ibmveth_get_strings,
971 	.get_sset_count		= ibmveth_get_sset_count,
972 	.get_ethtool_stats	= ibmveth_get_ethtool_stats,
973 	.get_link_ksettings	= netdev_get_link_ksettings,
974 };
975 
976 static int ibmveth_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
977 {
978 	return -EOPNOTSUPP;
979 }
980 
981 #define page_offset(v) ((unsigned long)(v) & ((1 << 12) - 1))
982 
983 static int ibmveth_send(struct ibmveth_adapter *adapter,
984 			union ibmveth_buf_desc *descs, unsigned long mss)
985 {
986 	unsigned long correlator;
987 	unsigned int retry_count;
988 	unsigned long ret;
989 
990 	/*
991 	 * The retry count sets a maximum for the number of broadcast and
992 	 * multicast destinations within the system.
993 	 */
994 	retry_count = 1024;
995 	correlator = 0;
996 	do {
997 		ret = h_send_logical_lan(adapter->vdev->unit_address,
998 					     descs[0].desc, descs[1].desc,
999 					     descs[2].desc, descs[3].desc,
1000 					     descs[4].desc, descs[5].desc,
1001 					     correlator, &correlator, mss,
1002 					     adapter->fw_large_send_support);
1003 	} while ((ret == H_BUSY) && (retry_count--));
1004 
1005 	if (ret != H_SUCCESS && ret != H_DROPPED) {
1006 		netdev_err(adapter->netdev, "tx: h_send_logical_lan failed "
1007 			   "with rc=%ld\n", ret);
1008 		return 1;
1009 	}
1010 
1011 	return 0;
1012 }
1013 
1014 static netdev_tx_t ibmveth_start_xmit(struct sk_buff *skb,
1015 				      struct net_device *netdev)
1016 {
1017 	struct ibmveth_adapter *adapter = netdev_priv(netdev);
1018 	unsigned int desc_flags;
1019 	union ibmveth_buf_desc descs[6];
1020 	int last, i;
1021 	int force_bounce = 0;
1022 	dma_addr_t dma_addr;
1023 	unsigned long mss = 0;
1024 
1025 	/* veth doesn't handle frag_list, so linearize the skb.
1026 	 * When GRO is enabled SKB's can have frag_list.
1027 	 */
1028 	if (adapter->is_active_trunk &&
1029 	    skb_has_frag_list(skb) && __skb_linearize(skb)) {
1030 		netdev->stats.tx_dropped++;
1031 		goto out;
1032 	}
1033 
1034 	/*
1035 	 * veth handles a maximum of 6 segments including the header, so
1036 	 * we have to linearize the skb if there are more than this.
1037 	 */
1038 	if (skb_shinfo(skb)->nr_frags > 5 && __skb_linearize(skb)) {
1039 		netdev->stats.tx_dropped++;
1040 		goto out;
1041 	}
1042 
1043 	/* veth can't checksum offload UDP */
1044 	if (skb->ip_summed == CHECKSUM_PARTIAL &&
1045 	    ((skb->protocol == htons(ETH_P_IP) &&
1046 	      ip_hdr(skb)->protocol != IPPROTO_TCP) ||
1047 	     (skb->protocol == htons(ETH_P_IPV6) &&
1048 	      ipv6_hdr(skb)->nexthdr != IPPROTO_TCP)) &&
1049 	    skb_checksum_help(skb)) {
1050 
1051 		netdev_err(netdev, "tx: failed to checksum packet\n");
1052 		netdev->stats.tx_dropped++;
1053 		goto out;
1054 	}
1055 
1056 	desc_flags = IBMVETH_BUF_VALID;
1057 
1058 	if (skb->ip_summed == CHECKSUM_PARTIAL) {
1059 		unsigned char *buf = skb_transport_header(skb) +
1060 						skb->csum_offset;
1061 
1062 		desc_flags |= (IBMVETH_BUF_NO_CSUM | IBMVETH_BUF_CSUM_GOOD);
1063 
1064 		/* Need to zero out the checksum */
1065 		buf[0] = 0;
1066 		buf[1] = 0;
1067 
1068 		if (skb_is_gso(skb) && adapter->fw_large_send_support)
1069 			desc_flags |= IBMVETH_BUF_LRG_SND;
1070 	}
1071 
1072 retry_bounce:
1073 	memset(descs, 0, sizeof(descs));
1074 
1075 	/*
1076 	 * If a linear packet is below the rx threshold then
1077 	 * copy it into the static bounce buffer. This avoids the
1078 	 * cost of a TCE insert and remove.
1079 	 */
1080 	if (force_bounce || (!skb_is_nonlinear(skb) &&
1081 				(skb->len < tx_copybreak))) {
1082 		skb_copy_from_linear_data(skb, adapter->bounce_buffer,
1083 					  skb->len);
1084 
1085 		descs[0].fields.flags_len = desc_flags | skb->len;
1086 		descs[0].fields.address = adapter->bounce_buffer_dma;
1087 
1088 		if (ibmveth_send(adapter, descs, 0)) {
1089 			adapter->tx_send_failed++;
1090 			netdev->stats.tx_dropped++;
1091 		} else {
1092 			netdev->stats.tx_packets++;
1093 			netdev->stats.tx_bytes += skb->len;
1094 		}
1095 
1096 		goto out;
1097 	}
1098 
1099 	/* Map the header */
1100 	dma_addr = dma_map_single(&adapter->vdev->dev, skb->data,
1101 				  skb_headlen(skb), DMA_TO_DEVICE);
1102 	if (dma_mapping_error(&adapter->vdev->dev, dma_addr))
1103 		goto map_failed;
1104 
1105 	descs[0].fields.flags_len = desc_flags | skb_headlen(skb);
1106 	descs[0].fields.address = dma_addr;
1107 
1108 	/* Map the frags */
1109 	for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
1110 		const skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
1111 
1112 		dma_addr = skb_frag_dma_map(&adapter->vdev->dev, frag, 0,
1113 					    skb_frag_size(frag), DMA_TO_DEVICE);
1114 
1115 		if (dma_mapping_error(&adapter->vdev->dev, dma_addr))
1116 			goto map_failed_frags;
1117 
1118 		descs[i+1].fields.flags_len = desc_flags | skb_frag_size(frag);
1119 		descs[i+1].fields.address = dma_addr;
1120 	}
1121 
1122 	if (skb->ip_summed == CHECKSUM_PARTIAL && skb_is_gso(skb)) {
1123 		if (adapter->fw_large_send_support) {
1124 			mss = (unsigned long)skb_shinfo(skb)->gso_size;
1125 			adapter->tx_large_packets++;
1126 		} else if (!skb_is_gso_v6(skb)) {
1127 			/* Put -1 in the IP checksum to tell phyp it
1128 			 * is a largesend packet. Put the mss in
1129 			 * the TCP checksum.
1130 			 */
1131 			ip_hdr(skb)->check = 0xffff;
1132 			tcp_hdr(skb)->check =
1133 				cpu_to_be16(skb_shinfo(skb)->gso_size);
1134 			adapter->tx_large_packets++;
1135 		}
1136 	}
1137 
1138 	if (ibmveth_send(adapter, descs, mss)) {
1139 		adapter->tx_send_failed++;
1140 		netdev->stats.tx_dropped++;
1141 	} else {
1142 		netdev->stats.tx_packets++;
1143 		netdev->stats.tx_bytes += skb->len;
1144 	}
1145 
1146 	dma_unmap_single(&adapter->vdev->dev,
1147 			 descs[0].fields.address,
1148 			 descs[0].fields.flags_len & IBMVETH_BUF_LEN_MASK,
1149 			 DMA_TO_DEVICE);
1150 
1151 	for (i = 1; i < skb_shinfo(skb)->nr_frags + 1; i++)
1152 		dma_unmap_page(&adapter->vdev->dev, descs[i].fields.address,
1153 			       descs[i].fields.flags_len & IBMVETH_BUF_LEN_MASK,
1154 			       DMA_TO_DEVICE);
1155 
1156 out:
1157 	dev_consume_skb_any(skb);
1158 	return NETDEV_TX_OK;
1159 
1160 map_failed_frags:
1161 	last = i+1;
1162 	for (i = 1; i < last; i++)
1163 		dma_unmap_page(&adapter->vdev->dev, descs[i].fields.address,
1164 			       descs[i].fields.flags_len & IBMVETH_BUF_LEN_MASK,
1165 			       DMA_TO_DEVICE);
1166 
1167 	dma_unmap_single(&adapter->vdev->dev,
1168 			 descs[0].fields.address,
1169 			 descs[0].fields.flags_len & IBMVETH_BUF_LEN_MASK,
1170 			 DMA_TO_DEVICE);
1171 map_failed:
1172 	if (!firmware_has_feature(FW_FEATURE_CMO))
1173 		netdev_err(netdev, "tx: unable to map xmit buffer\n");
1174 	adapter->tx_map_failed++;
1175 	if (skb_linearize(skb)) {
1176 		netdev->stats.tx_dropped++;
1177 		goto out;
1178 	}
1179 	force_bounce = 1;
1180 	goto retry_bounce;
1181 }
1182 
1183 static void ibmveth_rx_mss_helper(struct sk_buff *skb, u16 mss, int lrg_pkt)
1184 {
1185 	struct tcphdr *tcph;
1186 	int offset = 0;
1187 	int hdr_len;
1188 
1189 	/* only TCP packets will be aggregated */
1190 	if (skb->protocol == htons(ETH_P_IP)) {
1191 		struct iphdr *iph = (struct iphdr *)skb->data;
1192 
1193 		if (iph->protocol == IPPROTO_TCP) {
1194 			offset = iph->ihl * 4;
1195 			skb_shinfo(skb)->gso_type = SKB_GSO_TCPV4;
1196 		} else {
1197 			return;
1198 		}
1199 	} else if (skb->protocol == htons(ETH_P_IPV6)) {
1200 		struct ipv6hdr *iph6 = (struct ipv6hdr *)skb->data;
1201 
1202 		if (iph6->nexthdr == IPPROTO_TCP) {
1203 			offset = sizeof(struct ipv6hdr);
1204 			skb_shinfo(skb)->gso_type = SKB_GSO_TCPV6;
1205 		} else {
1206 			return;
1207 		}
1208 	} else {
1209 		return;
1210 	}
1211 	/* if mss is not set through Large Packet bit/mss in rx buffer,
1212 	 * expect that the mss will be written to the tcp header checksum.
1213 	 */
1214 	tcph = (struct tcphdr *)(skb->data + offset);
1215 	if (lrg_pkt) {
1216 		skb_shinfo(skb)->gso_size = mss;
1217 	} else if (offset) {
1218 		skb_shinfo(skb)->gso_size = ntohs(tcph->check);
1219 		tcph->check = 0;
1220 	}
1221 
1222 	if (skb_shinfo(skb)->gso_size) {
1223 		hdr_len = offset + tcph->doff * 4;
1224 		skb_shinfo(skb)->gso_segs =
1225 				DIV_ROUND_UP(skb->len - hdr_len,
1226 					     skb_shinfo(skb)->gso_size);
1227 	}
1228 }
1229 
1230 static void ibmveth_rx_csum_helper(struct sk_buff *skb,
1231 				   struct ibmveth_adapter *adapter)
1232 {
1233 	struct iphdr *iph = NULL;
1234 	struct ipv6hdr *iph6 = NULL;
1235 	__be16 skb_proto = 0;
1236 	u16 iphlen = 0;
1237 	u16 iph_proto = 0;
1238 	u16 tcphdrlen = 0;
1239 
1240 	skb_proto = be16_to_cpu(skb->protocol);
1241 
1242 	if (skb_proto == ETH_P_IP) {
1243 		iph = (struct iphdr *)skb->data;
1244 
1245 		/* If the IP checksum is not offloaded and if the packet
1246 		 *  is large send, the checksum must be rebuilt.
1247 		 */
1248 		if (iph->check == 0xffff) {
1249 			iph->check = 0;
1250 			iph->check = ip_fast_csum((unsigned char *)iph,
1251 						  iph->ihl);
1252 		}
1253 
1254 		iphlen = iph->ihl * 4;
1255 		iph_proto = iph->protocol;
1256 	} else if (skb_proto == ETH_P_IPV6) {
1257 		iph6 = (struct ipv6hdr *)skb->data;
1258 		iphlen = sizeof(struct ipv6hdr);
1259 		iph_proto = iph6->nexthdr;
1260 	}
1261 
1262 	/* In OVS environment, when a flow is not cached, specifically for a
1263 	 * new TCP connection, the first packet information is passed up
1264 	 * the user space for finding a flow. During this process, OVS computes
1265 	 * checksum on the first packet when CHECKSUM_PARTIAL flag is set.
1266 	 *
1267 	 * Given that we zeroed out TCP checksum field in transmit path
1268 	 * (refer ibmveth_start_xmit routine) as we set "no checksum bit",
1269 	 * OVS computed checksum will be incorrect w/o TCP pseudo checksum
1270 	 * in the packet. This leads to OVS dropping the packet and hence
1271 	 * TCP retransmissions are seen.
1272 	 *
1273 	 * So, re-compute TCP pseudo header checksum.
1274 	 */
1275 	if (iph_proto == IPPROTO_TCP && adapter->is_active_trunk) {
1276 		struct tcphdr *tcph = (struct tcphdr *)(skb->data + iphlen);
1277 
1278 		tcphdrlen = skb->len - iphlen;
1279 
1280 		/* Recompute TCP pseudo header checksum */
1281 		if (skb_proto == ETH_P_IP)
1282 			tcph->check = ~csum_tcpudp_magic(iph->saddr,
1283 					iph->daddr, tcphdrlen, iph_proto, 0);
1284 		else if (skb_proto == ETH_P_IPV6)
1285 			tcph->check = ~csum_ipv6_magic(&iph6->saddr,
1286 					&iph6->daddr, tcphdrlen, iph_proto, 0);
1287 
1288 		/* Setup SKB fields for checksum offload */
1289 		skb_partial_csum_set(skb, iphlen,
1290 				     offsetof(struct tcphdr, check));
1291 		skb_reset_network_header(skb);
1292 	}
1293 }
1294 
1295 static int ibmveth_poll(struct napi_struct *napi, int budget)
1296 {
1297 	struct ibmveth_adapter *adapter =
1298 			container_of(napi, struct ibmveth_adapter, napi);
1299 	struct net_device *netdev = adapter->netdev;
1300 	int frames_processed = 0;
1301 	unsigned long lpar_rc;
1302 	u16 mss = 0;
1303 
1304 	while (frames_processed < budget) {
1305 		if (!ibmveth_rxq_pending_buffer(adapter))
1306 			break;
1307 
1308 		smp_rmb();
1309 		if (!ibmveth_rxq_buffer_valid(adapter)) {
1310 			wmb(); /* suggested by larson1 */
1311 			adapter->rx_invalid_buffer++;
1312 			netdev_dbg(netdev, "recycling invalid buffer\n");
1313 			ibmveth_rxq_recycle_buffer(adapter);
1314 		} else {
1315 			struct sk_buff *skb, *new_skb;
1316 			int length = ibmveth_rxq_frame_length(adapter);
1317 			int offset = ibmveth_rxq_frame_offset(adapter);
1318 			int csum_good = ibmveth_rxq_csum_good(adapter);
1319 			int lrg_pkt = ibmveth_rxq_large_packet(adapter);
1320 
1321 			skb = ibmveth_rxq_get_buffer(adapter);
1322 
1323 			/* if the large packet bit is set in the rx queue
1324 			 * descriptor, the mss will be written by PHYP eight
1325 			 * bytes from the start of the rx buffer, which is
1326 			 * skb->data at this stage
1327 			 */
1328 			if (lrg_pkt) {
1329 				__be64 *rxmss = (__be64 *)(skb->data + 8);
1330 
1331 				mss = (u16)be64_to_cpu(*rxmss);
1332 			}
1333 
1334 			new_skb = NULL;
1335 			if (length < rx_copybreak)
1336 				new_skb = netdev_alloc_skb(netdev, length);
1337 
1338 			if (new_skb) {
1339 				skb_copy_to_linear_data(new_skb,
1340 							skb->data + offset,
1341 							length);
1342 				if (rx_flush)
1343 					ibmveth_flush_buffer(skb->data,
1344 						length + offset);
1345 				if (!ibmveth_rxq_recycle_buffer(adapter))
1346 					kfree_skb(skb);
1347 				skb = new_skb;
1348 			} else {
1349 				ibmveth_rxq_harvest_buffer(adapter);
1350 				skb_reserve(skb, offset);
1351 			}
1352 
1353 			skb_put(skb, length);
1354 			skb->protocol = eth_type_trans(skb, netdev);
1355 
1356 			if (csum_good) {
1357 				skb->ip_summed = CHECKSUM_UNNECESSARY;
1358 				ibmveth_rx_csum_helper(skb, adapter);
1359 			}
1360 
1361 			if (length > netdev->mtu + ETH_HLEN) {
1362 				ibmveth_rx_mss_helper(skb, mss, lrg_pkt);
1363 				adapter->rx_large_packets++;
1364 			}
1365 
1366 			napi_gro_receive(napi, skb);	/* send it up */
1367 
1368 			netdev->stats.rx_packets++;
1369 			netdev->stats.rx_bytes += length;
1370 			frames_processed++;
1371 		}
1372 	}
1373 
1374 	ibmveth_replenish_task(adapter);
1375 
1376 	if (frames_processed < budget) {
1377 		napi_complete_done(napi, frames_processed);
1378 
1379 		/* We think we are done - reenable interrupts,
1380 		 * then check once more to make sure we are done.
1381 		 */
1382 		lpar_rc = h_vio_signal(adapter->vdev->unit_address,
1383 				       VIO_IRQ_ENABLE);
1384 
1385 		BUG_ON(lpar_rc != H_SUCCESS);
1386 
1387 		if (ibmveth_rxq_pending_buffer(adapter) &&
1388 		    napi_reschedule(napi)) {
1389 			lpar_rc = h_vio_signal(adapter->vdev->unit_address,
1390 					       VIO_IRQ_DISABLE);
1391 		}
1392 	}
1393 
1394 	return frames_processed;
1395 }
1396 
1397 static irqreturn_t ibmveth_interrupt(int irq, void *dev_instance)
1398 {
1399 	struct net_device *netdev = dev_instance;
1400 	struct ibmveth_adapter *adapter = netdev_priv(netdev);
1401 	unsigned long lpar_rc;
1402 
1403 	if (napi_schedule_prep(&adapter->napi)) {
1404 		lpar_rc = h_vio_signal(adapter->vdev->unit_address,
1405 				       VIO_IRQ_DISABLE);
1406 		BUG_ON(lpar_rc != H_SUCCESS);
1407 		__napi_schedule(&adapter->napi);
1408 	}
1409 	return IRQ_HANDLED;
1410 }
1411 
1412 static void ibmveth_set_multicast_list(struct net_device *netdev)
1413 {
1414 	struct ibmveth_adapter *adapter = netdev_priv(netdev);
1415 	unsigned long lpar_rc;
1416 
1417 	if ((netdev->flags & IFF_PROMISC) ||
1418 	    (netdev_mc_count(netdev) > adapter->mcastFilterSize)) {
1419 		lpar_rc = h_multicast_ctrl(adapter->vdev->unit_address,
1420 					   IbmVethMcastEnableRecv |
1421 					   IbmVethMcastDisableFiltering,
1422 					   0);
1423 		if (lpar_rc != H_SUCCESS) {
1424 			netdev_err(netdev, "h_multicast_ctrl rc=%ld when "
1425 				   "entering promisc mode\n", lpar_rc);
1426 		}
1427 	} else {
1428 		struct netdev_hw_addr *ha;
1429 		/* clear the filter table & disable filtering */
1430 		lpar_rc = h_multicast_ctrl(adapter->vdev->unit_address,
1431 					   IbmVethMcastEnableRecv |
1432 					   IbmVethMcastDisableFiltering |
1433 					   IbmVethMcastClearFilterTable,
1434 					   0);
1435 		if (lpar_rc != H_SUCCESS) {
1436 			netdev_err(netdev, "h_multicast_ctrl rc=%ld when "
1437 				   "attempting to clear filter table\n",
1438 				   lpar_rc);
1439 		}
1440 		/* add the addresses to the filter table */
1441 		netdev_for_each_mc_addr(ha, netdev) {
1442 			/* add the multicast address to the filter table */
1443 			u64 mcast_addr;
1444 			mcast_addr = ibmveth_encode_mac_addr(ha->addr);
1445 			lpar_rc = h_multicast_ctrl(adapter->vdev->unit_address,
1446 						   IbmVethMcastAddFilter,
1447 						   mcast_addr);
1448 			if (lpar_rc != H_SUCCESS) {
1449 				netdev_err(netdev, "h_multicast_ctrl rc=%ld "
1450 					   "when adding an entry to the filter "
1451 					   "table\n", lpar_rc);
1452 			}
1453 		}
1454 
1455 		/* re-enable filtering */
1456 		lpar_rc = h_multicast_ctrl(adapter->vdev->unit_address,
1457 					   IbmVethMcastEnableFiltering,
1458 					   0);
1459 		if (lpar_rc != H_SUCCESS) {
1460 			netdev_err(netdev, "h_multicast_ctrl rc=%ld when "
1461 				   "enabling filtering\n", lpar_rc);
1462 		}
1463 	}
1464 }
1465 
1466 static int ibmveth_change_mtu(struct net_device *dev, int new_mtu)
1467 {
1468 	struct ibmveth_adapter *adapter = netdev_priv(dev);
1469 	struct vio_dev *viodev = adapter->vdev;
1470 	int new_mtu_oh = new_mtu + IBMVETH_BUFF_OH;
1471 	int i, rc;
1472 	int need_restart = 0;
1473 
1474 	for (i = 0; i < IBMVETH_NUM_BUFF_POOLS; i++)
1475 		if (new_mtu_oh <= adapter->rx_buff_pool[i].buff_size)
1476 			break;
1477 
1478 	if (i == IBMVETH_NUM_BUFF_POOLS)
1479 		return -EINVAL;
1480 
1481 	/* Deactivate all the buffer pools so that the next loop can activate
1482 	   only the buffer pools necessary to hold the new MTU */
1483 	if (netif_running(adapter->netdev)) {
1484 		need_restart = 1;
1485 		adapter->pool_config = 1;
1486 		ibmveth_close(adapter->netdev);
1487 		adapter->pool_config = 0;
1488 	}
1489 
1490 	/* Look for an active buffer pool that can hold the new MTU */
1491 	for (i = 0; i < IBMVETH_NUM_BUFF_POOLS; i++) {
1492 		adapter->rx_buff_pool[i].active = 1;
1493 
1494 		if (new_mtu_oh <= adapter->rx_buff_pool[i].buff_size) {
1495 			dev->mtu = new_mtu;
1496 			vio_cmo_set_dev_desired(viodev,
1497 						ibmveth_get_desired_dma
1498 						(viodev));
1499 			if (need_restart) {
1500 				return ibmveth_open(adapter->netdev);
1501 			}
1502 			return 0;
1503 		}
1504 	}
1505 
1506 	if (need_restart && (rc = ibmveth_open(adapter->netdev)))
1507 		return rc;
1508 
1509 	return -EINVAL;
1510 }
1511 
1512 #ifdef CONFIG_NET_POLL_CONTROLLER
1513 static void ibmveth_poll_controller(struct net_device *dev)
1514 {
1515 	ibmveth_replenish_task(netdev_priv(dev));
1516 	ibmveth_interrupt(dev->irq, dev);
1517 }
1518 #endif
1519 
1520 /**
1521  * ibmveth_get_desired_dma - Calculate IO memory desired by the driver
1522  *
1523  * @vdev: struct vio_dev for the device whose desired IO mem is to be returned
1524  *
1525  * Return value:
1526  *	Number of bytes of IO data the driver will need to perform well.
1527  */
1528 static unsigned long ibmveth_get_desired_dma(struct vio_dev *vdev)
1529 {
1530 	struct net_device *netdev = dev_get_drvdata(&vdev->dev);
1531 	struct ibmveth_adapter *adapter;
1532 	struct iommu_table *tbl;
1533 	unsigned long ret;
1534 	int i;
1535 	int rxqentries = 1;
1536 
1537 	tbl = get_iommu_table_base(&vdev->dev);
1538 
1539 	/* netdev inits at probe time along with the structures we need below*/
1540 	if (netdev == NULL)
1541 		return IOMMU_PAGE_ALIGN(IBMVETH_IO_ENTITLEMENT_DEFAULT, tbl);
1542 
1543 	adapter = netdev_priv(netdev);
1544 
1545 	ret = IBMVETH_BUFF_LIST_SIZE + IBMVETH_FILT_LIST_SIZE;
1546 	ret += IOMMU_PAGE_ALIGN(netdev->mtu, tbl);
1547 
1548 	for (i = 0; i < IBMVETH_NUM_BUFF_POOLS; i++) {
1549 		/* add the size of the active receive buffers */
1550 		if (adapter->rx_buff_pool[i].active)
1551 			ret +=
1552 			    adapter->rx_buff_pool[i].size *
1553 			    IOMMU_PAGE_ALIGN(adapter->rx_buff_pool[i].
1554 					     buff_size, tbl);
1555 		rxqentries += adapter->rx_buff_pool[i].size;
1556 	}
1557 	/* add the size of the receive queue entries */
1558 	ret += IOMMU_PAGE_ALIGN(
1559 		rxqentries * sizeof(struct ibmveth_rx_q_entry), tbl);
1560 
1561 	return ret;
1562 }
1563 
1564 static int ibmveth_set_mac_addr(struct net_device *dev, void *p)
1565 {
1566 	struct ibmveth_adapter *adapter = netdev_priv(dev);
1567 	struct sockaddr *addr = p;
1568 	u64 mac_address;
1569 	int rc;
1570 
1571 	if (!is_valid_ether_addr(addr->sa_data))
1572 		return -EADDRNOTAVAIL;
1573 
1574 	mac_address = ibmveth_encode_mac_addr(addr->sa_data);
1575 	rc = h_change_logical_lan_mac(adapter->vdev->unit_address, mac_address);
1576 	if (rc) {
1577 		netdev_err(adapter->netdev, "h_change_logical_lan_mac failed with rc=%d\n", rc);
1578 		return rc;
1579 	}
1580 
1581 	ether_addr_copy(dev->dev_addr, addr->sa_data);
1582 
1583 	return 0;
1584 }
1585 
1586 static const struct net_device_ops ibmveth_netdev_ops = {
1587 	.ndo_open		= ibmveth_open,
1588 	.ndo_stop		= ibmveth_close,
1589 	.ndo_start_xmit		= ibmveth_start_xmit,
1590 	.ndo_set_rx_mode	= ibmveth_set_multicast_list,
1591 	.ndo_do_ioctl		= ibmveth_ioctl,
1592 	.ndo_change_mtu		= ibmveth_change_mtu,
1593 	.ndo_fix_features	= ibmveth_fix_features,
1594 	.ndo_set_features	= ibmveth_set_features,
1595 	.ndo_validate_addr	= eth_validate_addr,
1596 	.ndo_set_mac_address    = ibmveth_set_mac_addr,
1597 #ifdef CONFIG_NET_POLL_CONTROLLER
1598 	.ndo_poll_controller	= ibmveth_poll_controller,
1599 #endif
1600 };
1601 
1602 static int ibmveth_probe(struct vio_dev *dev, const struct vio_device_id *id)
1603 {
1604 	int rc, i, mac_len;
1605 	struct net_device *netdev;
1606 	struct ibmveth_adapter *adapter;
1607 	unsigned char *mac_addr_p;
1608 	unsigned int *mcastFilterSize_p;
1609 	long ret;
1610 	unsigned long ret_attr;
1611 
1612 	dev_dbg(&dev->dev, "entering ibmveth_probe for UA 0x%x\n",
1613 		dev->unit_address);
1614 
1615 	mac_addr_p = (unsigned char *)vio_get_attribute(dev, VETH_MAC_ADDR,
1616 							&mac_len);
1617 	if (!mac_addr_p) {
1618 		dev_err(&dev->dev, "Can't find VETH_MAC_ADDR attribute\n");
1619 		return -EINVAL;
1620 	}
1621 	/* Workaround for old/broken pHyp */
1622 	if (mac_len == 8)
1623 		mac_addr_p += 2;
1624 	else if (mac_len != 6) {
1625 		dev_err(&dev->dev, "VETH_MAC_ADDR attribute wrong len %d\n",
1626 			mac_len);
1627 		return -EINVAL;
1628 	}
1629 
1630 	mcastFilterSize_p = (unsigned int *)vio_get_attribute(dev,
1631 						VETH_MCAST_FILTER_SIZE, NULL);
1632 	if (!mcastFilterSize_p) {
1633 		dev_err(&dev->dev, "Can't find VETH_MCAST_FILTER_SIZE "
1634 			"attribute\n");
1635 		return -EINVAL;
1636 	}
1637 
1638 	netdev = alloc_etherdev(sizeof(struct ibmveth_adapter));
1639 
1640 	if (!netdev)
1641 		return -ENOMEM;
1642 
1643 	adapter = netdev_priv(netdev);
1644 	dev_set_drvdata(&dev->dev, netdev);
1645 
1646 	adapter->vdev = dev;
1647 	adapter->netdev = netdev;
1648 	adapter->mcastFilterSize = *mcastFilterSize_p;
1649 	adapter->pool_config = 0;
1650 
1651 	netif_napi_add(netdev, &adapter->napi, ibmveth_poll, 16);
1652 
1653 	netdev->irq = dev->irq;
1654 	netdev->netdev_ops = &ibmveth_netdev_ops;
1655 	netdev->ethtool_ops = &netdev_ethtool_ops;
1656 	SET_NETDEV_DEV(netdev, &dev->dev);
1657 	netdev->hw_features = NETIF_F_SG;
1658 	if (vio_get_attribute(dev, "ibm,illan-options", NULL) != NULL) {
1659 		netdev->hw_features |= NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM |
1660 				       NETIF_F_RXCSUM;
1661 	}
1662 
1663 	netdev->features |= netdev->hw_features;
1664 
1665 	ret = h_illan_attributes(adapter->vdev->unit_address, 0, 0, &ret_attr);
1666 
1667 	/* If running older firmware, TSO should not be enabled by default */
1668 	if (ret == H_SUCCESS && (ret_attr & IBMVETH_ILLAN_LRG_SND_SUPPORT) &&
1669 	    !old_large_send) {
1670 		netdev->hw_features |= NETIF_F_TSO | NETIF_F_TSO6;
1671 		netdev->features |= netdev->hw_features;
1672 	} else {
1673 		netdev->hw_features |= NETIF_F_TSO;
1674 	}
1675 
1676 	adapter->is_active_trunk = false;
1677 	if (ret == H_SUCCESS && (ret_attr & IBMVETH_ILLAN_ACTIVE_TRUNK)) {
1678 		adapter->is_active_trunk = true;
1679 		netdev->hw_features |= NETIF_F_FRAGLIST;
1680 		netdev->features |= NETIF_F_FRAGLIST;
1681 	}
1682 
1683 	netdev->min_mtu = IBMVETH_MIN_MTU;
1684 	netdev->max_mtu = ETH_MAX_MTU;
1685 
1686 	memcpy(netdev->dev_addr, mac_addr_p, ETH_ALEN);
1687 
1688 	if (firmware_has_feature(FW_FEATURE_CMO))
1689 		memcpy(pool_count, pool_count_cmo, sizeof(pool_count));
1690 
1691 	for (i = 0; i < IBMVETH_NUM_BUFF_POOLS; i++) {
1692 		struct kobject *kobj = &adapter->rx_buff_pool[i].kobj;
1693 		int error;
1694 
1695 		ibmveth_init_buffer_pool(&adapter->rx_buff_pool[i], i,
1696 					 pool_count[i], pool_size[i],
1697 					 pool_active[i]);
1698 		error = kobject_init_and_add(kobj, &ktype_veth_pool,
1699 					     &dev->dev.kobj, "pool%d", i);
1700 		if (!error)
1701 			kobject_uevent(kobj, KOBJ_ADD);
1702 	}
1703 
1704 	netdev_dbg(netdev, "adapter @ 0x%p\n", adapter);
1705 	netdev_dbg(netdev, "registering netdev...\n");
1706 
1707 	ibmveth_set_features(netdev, netdev->features);
1708 
1709 	rc = register_netdev(netdev);
1710 
1711 	if (rc) {
1712 		netdev_dbg(netdev, "failed to register netdev rc=%d\n", rc);
1713 		free_netdev(netdev);
1714 		return rc;
1715 	}
1716 
1717 	netdev_dbg(netdev, "registered\n");
1718 
1719 	return 0;
1720 }
1721 
1722 static int ibmveth_remove(struct vio_dev *dev)
1723 {
1724 	struct net_device *netdev = dev_get_drvdata(&dev->dev);
1725 	struct ibmveth_adapter *adapter = netdev_priv(netdev);
1726 	int i;
1727 
1728 	for (i = 0; i < IBMVETH_NUM_BUFF_POOLS; i++)
1729 		kobject_put(&adapter->rx_buff_pool[i].kobj);
1730 
1731 	unregister_netdev(netdev);
1732 
1733 	free_netdev(netdev);
1734 	dev_set_drvdata(&dev->dev, NULL);
1735 
1736 	return 0;
1737 }
1738 
1739 static struct attribute veth_active_attr;
1740 static struct attribute veth_num_attr;
1741 static struct attribute veth_size_attr;
1742 
1743 static ssize_t veth_pool_show(struct kobject *kobj,
1744 			      struct attribute *attr, char *buf)
1745 {
1746 	struct ibmveth_buff_pool *pool = container_of(kobj,
1747 						      struct ibmveth_buff_pool,
1748 						      kobj);
1749 
1750 	if (attr == &veth_active_attr)
1751 		return sprintf(buf, "%d\n", pool->active);
1752 	else if (attr == &veth_num_attr)
1753 		return sprintf(buf, "%d\n", pool->size);
1754 	else if (attr == &veth_size_attr)
1755 		return sprintf(buf, "%d\n", pool->buff_size);
1756 	return 0;
1757 }
1758 
1759 static ssize_t veth_pool_store(struct kobject *kobj, struct attribute *attr,
1760 			       const char *buf, size_t count)
1761 {
1762 	struct ibmveth_buff_pool *pool = container_of(kobj,
1763 						      struct ibmveth_buff_pool,
1764 						      kobj);
1765 	struct net_device *netdev = dev_get_drvdata(
1766 	    container_of(kobj->parent, struct device, kobj));
1767 	struct ibmveth_adapter *adapter = netdev_priv(netdev);
1768 	long value = simple_strtol(buf, NULL, 10);
1769 	long rc;
1770 
1771 	if (attr == &veth_active_attr) {
1772 		if (value && !pool->active) {
1773 			if (netif_running(netdev)) {
1774 				if (ibmveth_alloc_buffer_pool(pool)) {
1775 					netdev_err(netdev,
1776 						   "unable to alloc pool\n");
1777 					return -ENOMEM;
1778 				}
1779 				pool->active = 1;
1780 				adapter->pool_config = 1;
1781 				ibmveth_close(netdev);
1782 				adapter->pool_config = 0;
1783 				if ((rc = ibmveth_open(netdev)))
1784 					return rc;
1785 			} else {
1786 				pool->active = 1;
1787 			}
1788 		} else if (!value && pool->active) {
1789 			int mtu = netdev->mtu + IBMVETH_BUFF_OH;
1790 			int i;
1791 			/* Make sure there is a buffer pool with buffers that
1792 			   can hold a packet of the size of the MTU */
1793 			for (i = 0; i < IBMVETH_NUM_BUFF_POOLS; i++) {
1794 				if (pool == &adapter->rx_buff_pool[i])
1795 					continue;
1796 				if (!adapter->rx_buff_pool[i].active)
1797 					continue;
1798 				if (mtu <= adapter->rx_buff_pool[i].buff_size)
1799 					break;
1800 			}
1801 
1802 			if (i == IBMVETH_NUM_BUFF_POOLS) {
1803 				netdev_err(netdev, "no active pool >= MTU\n");
1804 				return -EPERM;
1805 			}
1806 
1807 			if (netif_running(netdev)) {
1808 				adapter->pool_config = 1;
1809 				ibmveth_close(netdev);
1810 				pool->active = 0;
1811 				adapter->pool_config = 0;
1812 				if ((rc = ibmveth_open(netdev)))
1813 					return rc;
1814 			}
1815 			pool->active = 0;
1816 		}
1817 	} else if (attr == &veth_num_attr) {
1818 		if (value <= 0 || value > IBMVETH_MAX_POOL_COUNT) {
1819 			return -EINVAL;
1820 		} else {
1821 			if (netif_running(netdev)) {
1822 				adapter->pool_config = 1;
1823 				ibmveth_close(netdev);
1824 				adapter->pool_config = 0;
1825 				pool->size = value;
1826 				if ((rc = ibmveth_open(netdev)))
1827 					return rc;
1828 			} else {
1829 				pool->size = value;
1830 			}
1831 		}
1832 	} else if (attr == &veth_size_attr) {
1833 		if (value <= IBMVETH_BUFF_OH || value > IBMVETH_MAX_BUF_SIZE) {
1834 			return -EINVAL;
1835 		} else {
1836 			if (netif_running(netdev)) {
1837 				adapter->pool_config = 1;
1838 				ibmveth_close(netdev);
1839 				adapter->pool_config = 0;
1840 				pool->buff_size = value;
1841 				if ((rc = ibmveth_open(netdev)))
1842 					return rc;
1843 			} else {
1844 				pool->buff_size = value;
1845 			}
1846 		}
1847 	}
1848 
1849 	/* kick the interrupt handler to allocate/deallocate pools */
1850 	ibmveth_interrupt(netdev->irq, netdev);
1851 	return count;
1852 }
1853 
1854 
1855 #define ATTR(_name, _mode)				\
1856 	struct attribute veth_##_name##_attr = {	\
1857 	.name = __stringify(_name), .mode = _mode,	\
1858 	};
1859 
1860 static ATTR(active, 0644);
1861 static ATTR(num, 0644);
1862 static ATTR(size, 0644);
1863 
1864 static struct attribute *veth_pool_attrs[] = {
1865 	&veth_active_attr,
1866 	&veth_num_attr,
1867 	&veth_size_attr,
1868 	NULL,
1869 };
1870 
1871 static const struct sysfs_ops veth_pool_ops = {
1872 	.show   = veth_pool_show,
1873 	.store  = veth_pool_store,
1874 };
1875 
1876 static struct kobj_type ktype_veth_pool = {
1877 	.release        = NULL,
1878 	.sysfs_ops      = &veth_pool_ops,
1879 	.default_attrs  = veth_pool_attrs,
1880 };
1881 
1882 static int ibmveth_resume(struct device *dev)
1883 {
1884 	struct net_device *netdev = dev_get_drvdata(dev);
1885 	ibmveth_interrupt(netdev->irq, netdev);
1886 	return 0;
1887 }
1888 
1889 static const struct vio_device_id ibmveth_device_table[] = {
1890 	{ "network", "IBM,l-lan"},
1891 	{ "", "" }
1892 };
1893 MODULE_DEVICE_TABLE(vio, ibmveth_device_table);
1894 
1895 static const struct dev_pm_ops ibmveth_pm_ops = {
1896 	.resume = ibmveth_resume
1897 };
1898 
1899 static struct vio_driver ibmveth_driver = {
1900 	.id_table	= ibmveth_device_table,
1901 	.probe		= ibmveth_probe,
1902 	.remove		= ibmveth_remove,
1903 	.get_desired_dma = ibmveth_get_desired_dma,
1904 	.name		= ibmveth_driver_name,
1905 	.pm		= &ibmveth_pm_ops,
1906 };
1907 
1908 static int __init ibmveth_module_init(void)
1909 {
1910 	printk(KERN_DEBUG "%s: %s %s\n", ibmveth_driver_name,
1911 	       ibmveth_driver_string, ibmveth_driver_version);
1912 
1913 	return vio_register_driver(&ibmveth_driver);
1914 }
1915 
1916 static void __exit ibmveth_module_exit(void)
1917 {
1918 	vio_unregister_driver(&ibmveth_driver);
1919 }
1920 
1921 module_init(ibmveth_module_init);
1922 module_exit(ibmveth_module_exit);
1923