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1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * IBM Power Systems Virtual Management Channel Support.
4 *
5 * Copyright (c) 2004, 2018 IBM Corp.
6 * Dave Engebretsen [email protected]
7 * Steven Royer [email protected]
8 * Adam Reznechek [email protected]
9 * Bryant G. Ly <[email protected]>
10 */
11
12#include <linux/module.h>
13#include <linux/kernel.h>
14#include <linux/kthread.h>
15#include <linux/major.h>
16#include <linux/string.h>
17#include <linux/fcntl.h>
18#include <linux/slab.h>
19#include <linux/poll.h>
20#include <linux/init.h>
21#include <linux/fs.h>
22#include <linux/interrupt.h>
23#include <linux/spinlock.h>
24#include <linux/percpu.h>
25#include <linux/delay.h>
26#include <linux/uaccess.h>
27#include <linux/io.h>
28#include <linux/miscdevice.h>
29#include <linux/sched/signal.h>
30
31#include <asm/byteorder.h>
32#include <asm/irq.h>
33#include <asm/vio.h>
34
35#include "ibmvmc.h"
36
37#define IBMVMC_DRIVER_VERSION "1.0"
38
39/*
40 * Static global variables
41 */
42static DECLARE_WAIT_QUEUE_HEAD(ibmvmc_read_wait);
43
44static const char ibmvmc_driver_name[] = "ibmvmc";
45
46static struct ibmvmc_struct ibmvmc;
47static struct ibmvmc_hmc hmcs[MAX_HMCS];
48static struct crq_server_adapter ibmvmc_adapter;
49
50static int ibmvmc_max_buf_pool_size = DEFAULT_BUF_POOL_SIZE;
51static int ibmvmc_max_hmcs = DEFAULT_HMCS;
52static int ibmvmc_max_mtu = DEFAULT_MTU;
53
54static inline long h_copy_rdma(s64 length, u64 sliobn, u64 slioba,
55 u64 dliobn, u64 dlioba)
56{
57 long rc = 0;
58
59 /* Ensure all writes to source memory are visible before hcall */
60 dma_wmb();
61 pr_debug("ibmvmc: h_copy_rdma(0x%llx, 0x%llx, 0x%llx, 0x%llx, 0x%llx\n",
62 length, sliobn, slioba, dliobn, dlioba);
63 rc = plpar_hcall_norets(H_COPY_RDMA, length, sliobn, slioba,
64 dliobn, dlioba);
65 pr_debug("ibmvmc: h_copy_rdma rc = 0x%lx\n", rc);
66
67 return rc;
68}
69
70static inline void h_free_crq(uint32_t unit_address)
71{
72 long rc = 0;
73
74 do {
75 if (H_IS_LONG_BUSY(rc))
76 msleep(get_longbusy_msecs(rc));
77
78 rc = plpar_hcall_norets(H_FREE_CRQ, unit_address);
79 } while ((rc == H_BUSY) || (H_IS_LONG_BUSY(rc)));
80}
81
82/**
83 * h_request_vmc: - request a hypervisor virtual management channel device
84 * @vmc_index: drc index of the vmc device created
85 *
86 * Requests the hypervisor create a new virtual management channel device,
87 * allowing this partition to send hypervisor virtualization control
88 * commands.
89 *
90 * Return:
91 * 0 - Success
92 * Non-zero - Failure
93 */
94static inline long h_request_vmc(u32 *vmc_index)
95{
96 long rc = 0;
97 unsigned long retbuf[PLPAR_HCALL_BUFSIZE];
98
99 do {
100 if (H_IS_LONG_BUSY(rc))
101 msleep(get_longbusy_msecs(rc));
102
103 /* Call to request the VMC device from phyp */
104 rc = plpar_hcall(H_REQUEST_VMC, retbuf);
105 pr_debug("ibmvmc: %s rc = 0x%lx\n", __func__, rc);
106 *vmc_index = retbuf[0];
107 } while ((rc == H_BUSY) || (H_IS_LONG_BUSY(rc)));
108
109 return rc;
110}
111
112/* routines for managing a command/response queue */
113/**
114 * ibmvmc_handle_event: - Interrupt handler for crq events
115 * @irq: number of irq to handle, not used
116 * @dev_instance: crq_server_adapter that received interrupt
117 *
118 * Disables interrupts and schedules ibmvmc_task
119 *
120 * Always returns IRQ_HANDLED
121 */
122static irqreturn_t ibmvmc_handle_event(int irq, void *dev_instance)
123{
124 struct crq_server_adapter *adapter =
125 (struct crq_server_adapter *)dev_instance;
126
127 vio_disable_interrupts(to_vio_dev(adapter->dev));
128 tasklet_schedule(&adapter->work_task);
129
130 return IRQ_HANDLED;
131}
132
133/**
134 * ibmvmc_release_crq_queue - Release CRQ Queue
135 *
136 * @adapter: crq_server_adapter struct
137 *
138 * Return:
139 * 0 - Success
140 * Non-Zero - Failure
141 */
142static void ibmvmc_release_crq_queue(struct crq_server_adapter *adapter)
143{
144 struct vio_dev *vdev = to_vio_dev(adapter->dev);
145 struct crq_queue *queue = &adapter->queue;
146
147 free_irq(vdev->irq, (void *)adapter);
148 tasklet_kill(&adapter->work_task);
149
150 if (adapter->reset_task)
151 kthread_stop(adapter->reset_task);
152
153 h_free_crq(vdev->unit_address);
154 dma_unmap_single(adapter->dev,
155 queue->msg_token,
156 queue->size * sizeof(*queue->msgs), DMA_BIDIRECTIONAL);
157 free_page((unsigned long)queue->msgs);
158}
159
160/**
161 * ibmvmc_reset_crq_queue - Reset CRQ Queue
162 *
163 * @adapter: crq_server_adapter struct
164 *
165 * This function calls h_free_crq and then calls H_REG_CRQ and does all the
166 * bookkeeping to get us back to where we can communicate.
167 *
168 * Return:
169 * 0 - Success
170 * Non-Zero - Failure
171 */
172static int ibmvmc_reset_crq_queue(struct crq_server_adapter *adapter)
173{
174 struct vio_dev *vdev = to_vio_dev(adapter->dev);
175 struct crq_queue *queue = &adapter->queue;
176 int rc = 0;
177
178 /* Close the CRQ */
179 h_free_crq(vdev->unit_address);
180
181 /* Clean out the queue */
182 memset(queue->msgs, 0x00, PAGE_SIZE);
183 queue->cur = 0;
184
185 /* And re-open it again */
186 rc = plpar_hcall_norets(H_REG_CRQ,
187 vdev->unit_address,
188 queue->msg_token, PAGE_SIZE);
189 if (rc == 2)
190 /* Adapter is good, but other end is not ready */
191 dev_warn(adapter->dev, "Partner adapter not ready\n");
192 else if (rc != 0)
193 dev_err(adapter->dev, "couldn't register crq--rc 0x%x\n", rc);
194
195 return rc;
196}
197
198/**
199 * crq_queue_next_crq: - Returns the next entry in message queue
200 * @queue: crq_queue to use
201 *
202 * Returns pointer to next entry in queue, or NULL if there are no new
203 * entried in the CRQ.
204 */
205static struct ibmvmc_crq_msg *crq_queue_next_crq(struct crq_queue *queue)
206{
207 struct ibmvmc_crq_msg *crq;
208 unsigned long flags;
209
210 spin_lock_irqsave(&queue->lock, flags);
211 crq = &queue->msgs[queue->cur];
212 if (crq->valid & 0x80) {
213 if (++queue->cur == queue->size)
214 queue->cur = 0;
215
216 /* Ensure the read of the valid bit occurs before reading any
217 * other bits of the CRQ entry
218 */
219 dma_rmb();
220 } else {
221 crq = NULL;
222 }
223
224 spin_unlock_irqrestore(&queue->lock, flags);
225
226 return crq;
227}
228
229/**
230 * ibmvmc_send_crq - Send CRQ
231 *
232 * @adapter: crq_server_adapter struct
233 * @word1: Word1 Data field
234 * @word2: Word2 Data field
235 *
236 * Return:
237 * 0 - Success
238 * Non-Zero - Failure
239 */
240static long ibmvmc_send_crq(struct crq_server_adapter *adapter,
241 u64 word1, u64 word2)
242{
243 struct vio_dev *vdev = to_vio_dev(adapter->dev);
244 long rc = 0;
245
246 dev_dbg(adapter->dev, "(0x%x, 0x%016llx, 0x%016llx)\n",
247 vdev->unit_address, word1, word2);
248
249 /*
250 * Ensure the command buffer is flushed to memory before handing it
251 * over to the other side to prevent it from fetching any stale data.
252 */
253 dma_wmb();
254 rc = plpar_hcall_norets(H_SEND_CRQ, vdev->unit_address, word1, word2);
255 dev_dbg(adapter->dev, "rc = 0x%lx\n", rc);
256
257 return rc;
258}
259
260/**
261 * alloc_dma_buffer - Create DMA Buffer
262 *
263 * @vdev: vio_dev struct
264 * @size: Size field
265 * @dma_handle: DMA address field
266 *
267 * Allocates memory for the command queue and maps remote memory into an
268 * ioba.
269 *
270 * Returns a pointer to the buffer
271 */
272static void *alloc_dma_buffer(struct vio_dev *vdev, size_t size,
273 dma_addr_t *dma_handle)
274{
275 /* allocate memory */
276 void *buffer = kzalloc(size, GFP_ATOMIC);
277
278 if (!buffer) {
279 *dma_handle = 0;
280 return NULL;
281 }
282
283 /* DMA map */
284 *dma_handle = dma_map_single(&vdev->dev, buffer, size,
285 DMA_BIDIRECTIONAL);
286
287 if (dma_mapping_error(&vdev->dev, *dma_handle)) {
288 *dma_handle = 0;
289 kfree_sensitive(buffer);
290 return NULL;
291 }
292
293 return buffer;
294}
295
296/**
297 * free_dma_buffer - Free DMA Buffer
298 *
299 * @vdev: vio_dev struct
300 * @size: Size field
301 * @vaddr: Address field
302 * @dma_handle: DMA address field
303 *
304 * Releases memory for a command queue and unmaps mapped remote memory.
305 */
306static void free_dma_buffer(struct vio_dev *vdev, size_t size, void *vaddr,
307 dma_addr_t dma_handle)
308{
309 /* DMA unmap */
310 dma_unmap_single(&vdev->dev, dma_handle, size, DMA_BIDIRECTIONAL);
311
312 /* deallocate memory */
313 kfree_sensitive(vaddr);
314}
315
316/**
317 * ibmvmc_get_valid_hmc_buffer - Retrieve Valid HMC Buffer
318 *
319 * @hmc_index: HMC Index Field
320 *
321 * Return:
322 * Pointer to ibmvmc_buffer
323 */
324static struct ibmvmc_buffer *ibmvmc_get_valid_hmc_buffer(u8 hmc_index)
325{
326 struct ibmvmc_buffer *buffer;
327 struct ibmvmc_buffer *ret_buf = NULL;
328 unsigned long i;
329
330 if (hmc_index > ibmvmc.max_hmc_index)
331 return NULL;
332
333 buffer = hmcs[hmc_index].buffer;
334
335 for (i = 0; i < ibmvmc_max_buf_pool_size; i++) {
336 if (buffer[i].valid && buffer[i].free &&
337 buffer[i].owner == VMC_BUF_OWNER_ALPHA) {
338 buffer[i].free = 0;
339 ret_buf = &buffer[i];
340 break;
341 }
342 }
343
344 return ret_buf;
345}
346
347/**
348 * ibmvmc_get_free_hmc_buffer - Get Free HMC Buffer
349 *
350 * @adapter: crq_server_adapter struct
351 * @hmc_index: Hmc Index field
352 *
353 * Return:
354 * Pointer to ibmvmc_buffer
355 */
356static struct ibmvmc_buffer *ibmvmc_get_free_hmc_buffer(struct crq_server_adapter *adapter,
357 u8 hmc_index)
358{
359 struct ibmvmc_buffer *buffer;
360 struct ibmvmc_buffer *ret_buf = NULL;
361 unsigned long i;
362
363 if (hmc_index > ibmvmc.max_hmc_index) {
364 dev_info(adapter->dev, "get_free_hmc_buffer: invalid hmc_index=0x%x\n",
365 hmc_index);
366 return NULL;
367 }
368
369 buffer = hmcs[hmc_index].buffer;
370
371 for (i = 0; i < ibmvmc_max_buf_pool_size; i++) {
372 if (buffer[i].free &&
373 buffer[i].owner == VMC_BUF_OWNER_ALPHA) {
374 buffer[i].free = 0;
375 ret_buf = &buffer[i];
376 break;
377 }
378 }
379
380 return ret_buf;
381}
382
383/**
384 * ibmvmc_free_hmc_buffer - Free an HMC Buffer
385 *
386 * @hmc: ibmvmc_hmc struct
387 * @buffer: ibmvmc_buffer struct
388 *
389 */
390static void ibmvmc_free_hmc_buffer(struct ibmvmc_hmc *hmc,
391 struct ibmvmc_buffer *buffer)
392{
393 unsigned long flags;
394
395 spin_lock_irqsave(&hmc->lock, flags);
396 buffer->free = 1;
397 spin_unlock_irqrestore(&hmc->lock, flags);
398}
399
400/**
401 * ibmvmc_count_hmc_buffers - Count HMC Buffers
402 *
403 * @hmc_index: HMC Index field
404 * @valid: Valid number of buffers field
405 * @free: Free number of buffers field
406 *
407 */
408static void ibmvmc_count_hmc_buffers(u8 hmc_index, unsigned int *valid,
409 unsigned int *free)
410{
411 struct ibmvmc_buffer *buffer;
412 unsigned long i;
413 unsigned long flags;
414
415 if (hmc_index > ibmvmc.max_hmc_index)
416 return;
417
418 if (!valid || !free)
419 return;
420
421 *valid = 0; *free = 0;
422
423 buffer = hmcs[hmc_index].buffer;
424 spin_lock_irqsave(&hmcs[hmc_index].lock, flags);
425
426 for (i = 0; i < ibmvmc_max_buf_pool_size; i++) {
427 if (buffer[i].valid) {
428 *valid = *valid + 1;
429 if (buffer[i].free)
430 *free = *free + 1;
431 }
432 }
433
434 spin_unlock_irqrestore(&hmcs[hmc_index].lock, flags);
435}
436
437/**
438 * ibmvmc_get_free_hmc - Get Free HMC
439 *
440 * Return:
441 * Pointer to an available HMC Connection
442 * Null otherwise
443 */
444static struct ibmvmc_hmc *ibmvmc_get_free_hmc(void)
445{
446 unsigned long i;
447 unsigned long flags;
448
449 /*
450 * Find an available HMC connection.
451 */
452 for (i = 0; i <= ibmvmc.max_hmc_index; i++) {
453 spin_lock_irqsave(&hmcs[i].lock, flags);
454 if (hmcs[i].state == ibmhmc_state_free) {
455 hmcs[i].index = i;
456 hmcs[i].state = ibmhmc_state_initial;
457 spin_unlock_irqrestore(&hmcs[i].lock, flags);
458 return &hmcs[i];
459 }
460 spin_unlock_irqrestore(&hmcs[i].lock, flags);
461 }
462
463 return NULL;
464}
465
466/**
467 * ibmvmc_return_hmc - Return an HMC Connection
468 *
469 * @hmc: ibmvmc_hmc struct
470 * @release_readers: Number of readers connected to session
471 *
472 * This function releases the HMC connections back into the pool.
473 *
474 * Return:
475 * 0 - Success
476 * Non-zero - Failure
477 */
478static int ibmvmc_return_hmc(struct ibmvmc_hmc *hmc, bool release_readers)
479{
480 struct ibmvmc_buffer *buffer;
481 struct crq_server_adapter *adapter;
482 struct vio_dev *vdev;
483 unsigned long i;
484 unsigned long flags;
485
486 if (!hmc || !hmc->adapter)
487 return -EIO;
488
489 if (release_readers) {
490 if (hmc->file_session) {
491 struct ibmvmc_file_session *session = hmc->file_session;
492
493 session->valid = 0;
494 wake_up_interruptible(&ibmvmc_read_wait);
495 }
496 }
497
498 adapter = hmc->adapter;
499 vdev = to_vio_dev(adapter->dev);
500
501 spin_lock_irqsave(&hmc->lock, flags);
502 hmc->index = 0;
503 hmc->state = ibmhmc_state_free;
504 hmc->queue_head = 0;
505 hmc->queue_tail = 0;
506 buffer = hmc->buffer;
507 for (i = 0; i < ibmvmc_max_buf_pool_size; i++) {
508 if (buffer[i].valid) {
509 free_dma_buffer(vdev,
510 ibmvmc.max_mtu,
511 buffer[i].real_addr_local,
512 buffer[i].dma_addr_local);
513 dev_dbg(adapter->dev, "Forgot buffer id 0x%lx\n", i);
514 }
515 memset(&buffer[i], 0, sizeof(struct ibmvmc_buffer));
516
517 hmc->queue_outbound_msgs[i] = VMC_INVALID_BUFFER_ID;
518 }
519
520 spin_unlock_irqrestore(&hmc->lock, flags);
521
522 return 0;
523}
524
525/**
526 * ibmvmc_send_open - Interface Open
527 * @buffer: Pointer to ibmvmc_buffer struct
528 * @hmc: Pointer to ibmvmc_hmc struct
529 *
530 * This command is sent by the management partition as the result of a
531 * management partition device request. It causes the hypervisor to
532 * prepare a set of data buffers for the management application connection
533 * indicated HMC idx. A unique HMC Idx would be used if multiple management
534 * applications running concurrently were desired. Before responding to this
535 * command, the hypervisor must provide the management partition with at
536 * least one of these new buffers via the Add Buffer. This indicates whether
537 * the messages are inbound or outbound from the hypervisor.
538 *
539 * Return:
540 * 0 - Success
541 * Non-zero - Failure
542 */
543static int ibmvmc_send_open(struct ibmvmc_buffer *buffer,
544 struct ibmvmc_hmc *hmc)
545{
546 struct ibmvmc_crq_msg crq_msg;
547 struct crq_server_adapter *adapter;
548 __be64 *crq_as_u64 = (__be64 *)&crq_msg;
549 int rc = 0;
550
551 if (!hmc || !hmc->adapter)
552 return -EIO;
553
554 adapter = hmc->adapter;
555
556 dev_dbg(adapter->dev, "send_open: 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx\n",
557 (unsigned long)buffer->size, (unsigned long)adapter->liobn,
558 (unsigned long)buffer->dma_addr_local,
559 (unsigned long)adapter->riobn,
560 (unsigned long)buffer->dma_addr_remote);
561
562 rc = h_copy_rdma(buffer->size,
563 adapter->liobn,
564 buffer->dma_addr_local,
565 adapter->riobn,
566 buffer->dma_addr_remote);
567 if (rc) {
568 dev_err(adapter->dev, "Error: In send_open, h_copy_rdma rc 0x%x\n",
569 rc);
570 return -EIO;
571 }
572
573 hmc->state = ibmhmc_state_opening;
574
575 crq_msg.valid = 0x80;
576 crq_msg.type = VMC_MSG_OPEN;
577 crq_msg.status = 0;
578 crq_msg.var1.rsvd = 0;
579 crq_msg.hmc_session = hmc->session;
580 crq_msg.hmc_index = hmc->index;
581 crq_msg.var2.buffer_id = cpu_to_be16(buffer->id);
582 crq_msg.rsvd = 0;
583 crq_msg.var3.rsvd = 0;
584
585 ibmvmc_send_crq(adapter, be64_to_cpu(crq_as_u64[0]),
586 be64_to_cpu(crq_as_u64[1]));
587
588 return rc;
589}
590
591/**
592 * ibmvmc_send_close - Interface Close
593 * @hmc: Pointer to ibmvmc_hmc struct
594 *
595 * This command is sent by the management partition to terminate a
596 * management application to hypervisor connection. When this command is
597 * sent, the management partition has quiesced all I/O operations to all
598 * buffers associated with this management application connection, and
599 * has freed any storage for these buffers.
600 *
601 * Return:
602 * 0 - Success
603 * Non-zero - Failure
604 */
605static int ibmvmc_send_close(struct ibmvmc_hmc *hmc)
606{
607 struct ibmvmc_crq_msg crq_msg;
608 struct crq_server_adapter *adapter;
609 __be64 *crq_as_u64 = (__be64 *)&crq_msg;
610 int rc = 0;
611
612 if (!hmc || !hmc->adapter)
613 return -EIO;
614
615 adapter = hmc->adapter;
616
617 dev_info(adapter->dev, "CRQ send: close\n");
618
619 crq_msg.valid = 0x80;
620 crq_msg.type = VMC_MSG_CLOSE;
621 crq_msg.status = 0;
622 crq_msg.var1.rsvd = 0;
623 crq_msg.hmc_session = hmc->session;
624 crq_msg.hmc_index = hmc->index;
625 crq_msg.var2.rsvd = 0;
626 crq_msg.rsvd = 0;
627 crq_msg.var3.rsvd = 0;
628
629 ibmvmc_send_crq(adapter, be64_to_cpu(crq_as_u64[0]),
630 be64_to_cpu(crq_as_u64[1]));
631
632 return rc;
633}
634
635/**
636 * ibmvmc_send_capabilities - Send VMC Capabilities
637 *
638 * @adapter: crq_server_adapter struct
639 *
640 * The capabilities message is an administrative message sent after the CRQ
641 * initialization sequence of messages and is used to exchange VMC capabilities
642 * between the management partition and the hypervisor. The management
643 * partition must send this message and the hypervisor must respond with VMC
644 * capabilities Response message before HMC interface message can begin. Any
645 * HMC interface messages received before the exchange of capabilities has
646 * complete are dropped.
647 *
648 * Return:
649 * 0 - Success
650 */
651static int ibmvmc_send_capabilities(struct crq_server_adapter *adapter)
652{
653 struct ibmvmc_admin_crq_msg crq_msg;
654 __be64 *crq_as_u64 = (__be64 *)&crq_msg;
655
656 dev_dbg(adapter->dev, "ibmvmc: CRQ send: capabilities\n");
657 crq_msg.valid = 0x80;
658 crq_msg.type = VMC_MSG_CAP;
659 crq_msg.status = 0;
660 crq_msg.rsvd[0] = 0;
661 crq_msg.rsvd[1] = 0;
662 crq_msg.max_hmc = ibmvmc_max_hmcs;
663 crq_msg.max_mtu = cpu_to_be32(ibmvmc_max_mtu);
664 crq_msg.pool_size = cpu_to_be16(ibmvmc_max_buf_pool_size);
665 crq_msg.crq_size = cpu_to_be16(adapter->queue.size);
666 crq_msg.version = cpu_to_be16(IBMVMC_PROTOCOL_VERSION);
667
668 ibmvmc_send_crq(adapter, be64_to_cpu(crq_as_u64[0]),
669 be64_to_cpu(crq_as_u64[1]));
670
671 ibmvmc.state = ibmvmc_state_capabilities;
672
673 return 0;
674}
675
676/**
677 * ibmvmc_send_add_buffer_resp - Add Buffer Response
678 *
679 * @adapter: crq_server_adapter struct
680 * @status: Status field
681 * @hmc_session: HMC Session field
682 * @hmc_index: HMC Index field
683 * @buffer_id: Buffer Id field
684 *
685 * This command is sent by the management partition to the hypervisor in
686 * response to the Add Buffer message. The Status field indicates the result of
687 * the command.
688 *
689 * Return:
690 * 0 - Success
691 */
692static int ibmvmc_send_add_buffer_resp(struct crq_server_adapter *adapter,
693 u8 status, u8 hmc_session,
694 u8 hmc_index, u16 buffer_id)
695{
696 struct ibmvmc_crq_msg crq_msg;
697 __be64 *crq_as_u64 = (__be64 *)&crq_msg;
698
699 dev_dbg(adapter->dev, "CRQ send: add_buffer_resp\n");
700 crq_msg.valid = 0x80;
701 crq_msg.type = VMC_MSG_ADD_BUF_RESP;
702 crq_msg.status = status;
703 crq_msg.var1.rsvd = 0;
704 crq_msg.hmc_session = hmc_session;
705 crq_msg.hmc_index = hmc_index;
706 crq_msg.var2.buffer_id = cpu_to_be16(buffer_id);
707 crq_msg.rsvd = 0;
708 crq_msg.var3.rsvd = 0;
709
710 ibmvmc_send_crq(adapter, be64_to_cpu(crq_as_u64[0]),
711 be64_to_cpu(crq_as_u64[1]));
712
713 return 0;
714}
715
716/**
717 * ibmvmc_send_rem_buffer_resp - Remove Buffer Response
718 *
719 * @adapter: crq_server_adapter struct
720 * @status: Status field
721 * @hmc_session: HMC Session field
722 * @hmc_index: HMC Index field
723 * @buffer_id: Buffer Id field
724 *
725 * This command is sent by the management partition to the hypervisor in
726 * response to the Remove Buffer message. The Buffer ID field indicates
727 * which buffer the management partition selected to remove. The Status
728 * field indicates the result of the command.
729 *
730 * Return:
731 * 0 - Success
732 */
733static int ibmvmc_send_rem_buffer_resp(struct crq_server_adapter *adapter,
734 u8 status, u8 hmc_session,
735 u8 hmc_index, u16 buffer_id)
736{
737 struct ibmvmc_crq_msg crq_msg;
738 __be64 *crq_as_u64 = (__be64 *)&crq_msg;
739
740 dev_dbg(adapter->dev, "CRQ send: rem_buffer_resp\n");
741 crq_msg.valid = 0x80;
742 crq_msg.type = VMC_MSG_REM_BUF_RESP;
743 crq_msg.status = status;
744 crq_msg.var1.rsvd = 0;
745 crq_msg.hmc_session = hmc_session;
746 crq_msg.hmc_index = hmc_index;
747 crq_msg.var2.buffer_id = cpu_to_be16(buffer_id);
748 crq_msg.rsvd = 0;
749 crq_msg.var3.rsvd = 0;
750
751 ibmvmc_send_crq(adapter, be64_to_cpu(crq_as_u64[0]),
752 be64_to_cpu(crq_as_u64[1]));
753
754 return 0;
755}
756
757/**
758 * ibmvmc_send_msg - Signal Message
759 *
760 * @adapter: crq_server_adapter struct
761 * @buffer: ibmvmc_buffer struct
762 * @hmc: ibmvmc_hmc struct
763 * @msg_len: message length field
764 *
765 * This command is sent between the management partition and the hypervisor
766 * in order to signal the arrival of an HMC protocol message. The command
767 * can be sent by both the management partition and the hypervisor. It is
768 * used for all traffic between the management application and the hypervisor,
769 * regardless of who initiated the communication.
770 *
771 * There is no response to this message.
772 *
773 * Return:
774 * 0 - Success
775 * Non-zero - Failure
776 */
777static int ibmvmc_send_msg(struct crq_server_adapter *adapter,
778 struct ibmvmc_buffer *buffer,
779 struct ibmvmc_hmc *hmc, int msg_len)
780{
781 struct ibmvmc_crq_msg crq_msg;
782 __be64 *crq_as_u64 = (__be64 *)&crq_msg;
783 int rc = 0;
784
785 dev_dbg(adapter->dev, "CRQ send: rdma to HV\n");
786 rc = h_copy_rdma(msg_len,
787 adapter->liobn,
788 buffer->dma_addr_local,
789 adapter->riobn,
790 buffer->dma_addr_remote);
791 if (rc) {
792 dev_err(adapter->dev, "Error in send_msg, h_copy_rdma rc 0x%x\n",
793 rc);
794 return rc;
795 }
796
797 crq_msg.valid = 0x80;
798 crq_msg.type = VMC_MSG_SIGNAL;
799 crq_msg.status = 0;
800 crq_msg.var1.rsvd = 0;
801 crq_msg.hmc_session = hmc->session;
802 crq_msg.hmc_index = hmc->index;
803 crq_msg.var2.buffer_id = cpu_to_be16(buffer->id);
804 crq_msg.var3.msg_len = cpu_to_be32(msg_len);
805 dev_dbg(adapter->dev, "CRQ send: msg to HV 0x%llx 0x%llx\n",
806 be64_to_cpu(crq_as_u64[0]), be64_to_cpu(crq_as_u64[1]));
807
808 buffer->owner = VMC_BUF_OWNER_HV;
809 ibmvmc_send_crq(adapter, be64_to_cpu(crq_as_u64[0]),
810 be64_to_cpu(crq_as_u64[1]));
811
812 return rc;
813}
814
815/**
816 * ibmvmc_open - Open Session
817 *
818 * @inode: inode struct
819 * @file: file struct
820 *
821 * Return:
822 * 0 - Success
823 * Non-zero - Failure
824 */
825static int ibmvmc_open(struct inode *inode, struct file *file)
826{
827 struct ibmvmc_file_session *session;
828
829 pr_debug("%s: inode = 0x%lx, file = 0x%lx, state = 0x%x\n", __func__,
830 (unsigned long)inode, (unsigned long)file,
831 ibmvmc.state);
832
833 session = kzalloc_obj(*session);
834 if (!session)
835 return -ENOMEM;
836
837 session->file = file;
838 file->private_data = session;
839
840 return 0;
841}
842
843/**
844 * ibmvmc_close - Close Session
845 *
846 * @inode: inode struct
847 * @file: file struct
848 *
849 * Return:
850 * 0 - Success
851 * Non-zero - Failure
852 */
853static int ibmvmc_close(struct inode *inode, struct file *file)
854{
855 struct ibmvmc_file_session *session;
856 struct ibmvmc_hmc *hmc;
857 int rc = 0;
858 unsigned long flags;
859
860 pr_debug("%s: file = 0x%lx, state = 0x%x\n", __func__,
861 (unsigned long)file, ibmvmc.state);
862
863 session = file->private_data;
864 if (!session)
865 return -EIO;
866
867 hmc = session->hmc;
868 if (hmc) {
869 if (!hmc->adapter)
870 return -EIO;
871
872 if (ibmvmc.state == ibmvmc_state_failed) {
873 dev_warn(hmc->adapter->dev, "close: state_failed\n");
874 return -EIO;
875 }
876
877 spin_lock_irqsave(&hmc->lock, flags);
878 if (hmc->state >= ibmhmc_state_opening) {
879 rc = ibmvmc_send_close(hmc);
880 if (rc)
881 dev_warn(hmc->adapter->dev, "close: send_close failed.\n");
882 }
883 spin_unlock_irqrestore(&hmc->lock, flags);
884 }
885
886 kfree_sensitive(session);
887
888 return rc;
889}
890
891/**
892 * ibmvmc_read - Read
893 *
894 * @file: file struct
895 * @buf: Character buffer
896 * @nbytes: Size in bytes
897 * @ppos: Offset
898 *
899 * Return:
900 * 0 - Success
901 * Non-zero - Failure
902 */
903static ssize_t ibmvmc_read(struct file *file, char *buf, size_t nbytes,
904 loff_t *ppos)
905{
906 struct ibmvmc_file_session *session;
907 struct ibmvmc_hmc *hmc;
908 struct crq_server_adapter *adapter;
909 struct ibmvmc_buffer *buffer;
910 ssize_t n;
911 ssize_t retval = 0;
912 unsigned long flags;
913 DEFINE_WAIT(wait);
914
915 pr_debug("ibmvmc: read: file = 0x%lx, buf = 0x%lx, nbytes = 0x%lx\n",
916 (unsigned long)file, (unsigned long)buf,
917 (unsigned long)nbytes);
918
919 if (nbytes == 0)
920 return 0;
921
922 if (nbytes > ibmvmc.max_mtu) {
923 pr_warn("ibmvmc: read: nbytes invalid 0x%x\n",
924 (unsigned int)nbytes);
925 return -EINVAL;
926 }
927
928 session = file->private_data;
929 if (!session) {
930 pr_warn("ibmvmc: read: no session\n");
931 return -EIO;
932 }
933
934 hmc = session->hmc;
935 if (!hmc) {
936 pr_warn("ibmvmc: read: no hmc\n");
937 return -EIO;
938 }
939
940 adapter = hmc->adapter;
941 if (!adapter) {
942 pr_warn("ibmvmc: read: no adapter\n");
943 return -EIO;
944 }
945
946 do {
947 prepare_to_wait(&ibmvmc_read_wait, &wait, TASK_INTERRUPTIBLE);
948
949 spin_lock_irqsave(&hmc->lock, flags);
950 if (hmc->queue_tail != hmc->queue_head)
951 /* Data is available */
952 break;
953
954 spin_unlock_irqrestore(&hmc->lock, flags);
955
956 if (!session->valid) {
957 retval = -EBADFD;
958 goto out;
959 }
960 if (file->f_flags & O_NONBLOCK) {
961 retval = -EAGAIN;
962 goto out;
963 }
964
965 schedule();
966
967 if (signal_pending(current)) {
968 retval = -ERESTARTSYS;
969 goto out;
970 }
971 } while (1);
972
973 buffer = &(hmc->buffer[hmc->queue_outbound_msgs[hmc->queue_tail]]);
974 hmc->queue_tail++;
975 if (hmc->queue_tail == ibmvmc_max_buf_pool_size)
976 hmc->queue_tail = 0;
977 spin_unlock_irqrestore(&hmc->lock, flags);
978
979 nbytes = min_t(size_t, nbytes, buffer->msg_len);
980 n = copy_to_user((void *)buf, buffer->real_addr_local, nbytes);
981 dev_dbg(adapter->dev, "read: copy to user nbytes = 0x%lx.\n", nbytes);
982 ibmvmc_free_hmc_buffer(hmc, buffer);
983 retval = nbytes;
984
985 if (n) {
986 dev_warn(adapter->dev, "read: copy to user failed.\n");
987 retval = -EFAULT;
988 }
989
990 out:
991 finish_wait(&ibmvmc_read_wait, &wait);
992 dev_dbg(adapter->dev, "read: out %ld\n", retval);
993 return retval;
994}
995
996/**
997 * ibmvmc_poll - Poll
998 *
999 * @file: file struct
1000 * @wait: Poll Table
1001 *
1002 * Return:
1003 * poll.h return values
1004 */
1005static unsigned int ibmvmc_poll(struct file *file, poll_table *wait)
1006{
1007 struct ibmvmc_file_session *session;
1008 struct ibmvmc_hmc *hmc;
1009 unsigned int mask = 0;
1010
1011 session = file->private_data;
1012 if (!session)
1013 return 0;
1014
1015 hmc = session->hmc;
1016 if (!hmc)
1017 return 0;
1018
1019 poll_wait(file, &ibmvmc_read_wait, wait);
1020
1021 if (hmc->queue_head != hmc->queue_tail)
1022 mask |= POLLIN | POLLRDNORM;
1023
1024 return mask;
1025}
1026
1027/**
1028 * ibmvmc_write - Write
1029 *
1030 * @file: file struct
1031 * @buffer: Character buffer
1032 * @count: Count field
1033 * @ppos: Offset
1034 *
1035 * Return:
1036 * 0 - Success
1037 * Non-zero - Failure
1038 */
1039static ssize_t ibmvmc_write(struct file *file, const char *buffer,
1040 size_t count, loff_t *ppos)
1041{
1042 struct inode *inode;
1043 struct ibmvmc_buffer *vmc_buffer = NULL;
1044 struct ibmvmc_file_session *session;
1045 struct crq_server_adapter *adapter;
1046 struct ibmvmc_hmc *hmc;
1047 unsigned char *buf;
1048 unsigned long flags;
1049 size_t bytes;
1050 const char *p = buffer;
1051 size_t c = count;
1052 int ret = 0;
1053
1054 session = file->private_data;
1055 if (!session)
1056 return -EIO;
1057
1058 hmc = session->hmc;
1059 if (!hmc)
1060 return -EIO;
1061
1062 spin_lock_irqsave(&hmc->lock, flags);
1063 if (hmc->state == ibmhmc_state_free) {
1064 /* HMC connection is not valid (possibly was reset under us). */
1065 ret = -EIO;
1066 goto out;
1067 }
1068
1069 adapter = hmc->adapter;
1070 if (!adapter) {
1071 ret = -EIO;
1072 goto out;
1073 }
1074
1075 if (count > ibmvmc.max_mtu) {
1076 dev_warn(adapter->dev, "invalid buffer size 0x%lx\n",
1077 (unsigned long)count);
1078 ret = -EIO;
1079 goto out;
1080 }
1081
1082 /* Waiting for the open resp message to the ioctl(1) - retry */
1083 if (hmc->state == ibmhmc_state_opening) {
1084 ret = -EBUSY;
1085 goto out;
1086 }
1087
1088 /* Make sure the ioctl() was called & the open msg sent, and that
1089 * the HMC connection has not failed.
1090 */
1091 if (hmc->state != ibmhmc_state_ready) {
1092 ret = -EIO;
1093 goto out;
1094 }
1095
1096 vmc_buffer = ibmvmc_get_valid_hmc_buffer(hmc->index);
1097 if (!vmc_buffer) {
1098 /* No buffer available for the msg send, or we have not yet
1099 * completed the open/open_resp sequence. Retry until this is
1100 * complete.
1101 */
1102 ret = -EBUSY;
1103 goto out;
1104 }
1105 if (!vmc_buffer->real_addr_local) {
1106 dev_err(adapter->dev, "no buffer storage assigned\n");
1107 ret = -EIO;
1108 goto out;
1109 }
1110 buf = vmc_buffer->real_addr_local;
1111
1112 while (c > 0) {
1113 bytes = min_t(size_t, c, vmc_buffer->size);
1114
1115 bytes -= copy_from_user(buf, p, bytes);
1116 if (!bytes) {
1117 ret = -EFAULT;
1118 goto out;
1119 }
1120 c -= bytes;
1121 p += bytes;
1122 }
1123 if (p == buffer)
1124 goto out;
1125
1126 inode = file_inode(file);
1127 inode_set_mtime_to_ts(inode, inode_set_ctime_current(inode));
1128 mark_inode_dirty(inode);
1129
1130 dev_dbg(adapter->dev, "write: file = 0x%lx, count = 0x%lx\n",
1131 (unsigned long)file, (unsigned long)count);
1132
1133 if (ibmvmc_send_msg(adapter, vmc_buffer, hmc, count)) {
1134 ret = -EIO;
1135 goto out;
1136 }
1137 vmc_buffer = NULL;
1138 ret = p - buffer;
1139 out:
1140 if (vmc_buffer)
1141 vmc_buffer->free = 1;
1142 spin_unlock_irqrestore(&hmc->lock, flags);
1143 return (ssize_t)(ret);
1144}
1145
1146/**
1147 * ibmvmc_setup_hmc - Setup the HMC
1148 *
1149 * @session: ibmvmc_file_session struct
1150 *
1151 * Return:
1152 * 0 - Success
1153 * Non-zero - Failure
1154 */
1155static long ibmvmc_setup_hmc(struct ibmvmc_file_session *session)
1156{
1157 struct ibmvmc_hmc *hmc;
1158 unsigned int valid, free, index;
1159
1160 if (ibmvmc.state == ibmvmc_state_failed) {
1161 pr_warn("ibmvmc: Reserve HMC: state_failed\n");
1162 return -EIO;
1163 }
1164
1165 if (ibmvmc.state < ibmvmc_state_ready) {
1166 pr_warn("ibmvmc: Reserve HMC: not state_ready\n");
1167 return -EAGAIN;
1168 }
1169
1170 /* Device is busy until capabilities have been exchanged and we
1171 * have a generic buffer for each possible HMC connection.
1172 */
1173 for (index = 0; index <= ibmvmc.max_hmc_index; index++) {
1174 valid = 0;
1175 ibmvmc_count_hmc_buffers(index, &valid, &free);
1176 if (valid == 0) {
1177 pr_warn("ibmvmc: buffers not ready for index %d\n",
1178 index);
1179 return -ENOBUFS;
1180 }
1181 }
1182
1183 /* Get an hmc object, and transition to ibmhmc_state_initial */
1184 hmc = ibmvmc_get_free_hmc();
1185 if (!hmc) {
1186 pr_warn("%s: free hmc not found\n", __func__);
1187 return -EBUSY;
1188 }
1189
1190 hmc->session = hmc->session + 1;
1191 if (hmc->session == 0xff)
1192 hmc->session = 1;
1193
1194 session->hmc = hmc;
1195 hmc->adapter = &ibmvmc_adapter;
1196 hmc->file_session = session;
1197 session->valid = 1;
1198
1199 return 0;
1200}
1201
1202/**
1203 * ibmvmc_ioctl_sethmcid - IOCTL Set HMC ID
1204 *
1205 * @session: ibmvmc_file_session struct
1206 * @new_hmc_id: HMC id field
1207 *
1208 * IOCTL command to setup the hmc id
1209 *
1210 * Return:
1211 * 0 - Success
1212 * Non-zero - Failure
1213 */
1214static long ibmvmc_ioctl_sethmcid(struct ibmvmc_file_session *session,
1215 unsigned char __user *new_hmc_id)
1216{
1217 struct ibmvmc_hmc *hmc;
1218 struct ibmvmc_buffer *buffer;
1219 size_t bytes;
1220 char print_buffer[HMC_ID_LEN + 1];
1221 unsigned long flags;
1222 long rc = 0;
1223
1224 /* Reserve HMC session */
1225 hmc = session->hmc;
1226 if (!hmc) {
1227 rc = ibmvmc_setup_hmc(session);
1228 if (rc)
1229 return rc;
1230
1231 hmc = session->hmc;
1232 if (!hmc) {
1233 pr_err("ibmvmc: setup_hmc success but no hmc\n");
1234 return -EIO;
1235 }
1236 }
1237
1238 if (hmc->state != ibmhmc_state_initial) {
1239 pr_warn("ibmvmc: sethmcid: invalid state to send open 0x%x\n",
1240 hmc->state);
1241 return -EIO;
1242 }
1243
1244 bytes = copy_from_user(hmc->hmc_id, new_hmc_id, HMC_ID_LEN);
1245 if (bytes)
1246 return -EFAULT;
1247
1248 /* Send Open Session command */
1249 spin_lock_irqsave(&hmc->lock, flags);
1250 buffer = ibmvmc_get_valid_hmc_buffer(hmc->index);
1251 spin_unlock_irqrestore(&hmc->lock, flags);
1252
1253 if (!buffer || !buffer->real_addr_local) {
1254 pr_warn("ibmvmc: sethmcid: no buffer available\n");
1255 return -EIO;
1256 }
1257
1258 strscpy(print_buffer, hmc->hmc_id, sizeof(print_buffer));
1259 pr_info("ibmvmc: sethmcid: Set HMC ID: \"%s\"\n", print_buffer);
1260
1261 memcpy(buffer->real_addr_local, hmc->hmc_id, HMC_ID_LEN);
1262 /* RDMA over ID, send open msg, change state to ibmhmc_state_opening */
1263 rc = ibmvmc_send_open(buffer, hmc);
1264
1265 return rc;
1266}
1267
1268/**
1269 * ibmvmc_ioctl_query - IOCTL Query
1270 *
1271 * @session: ibmvmc_file_session struct
1272 * @ret_struct: ibmvmc_query_struct
1273 *
1274 * Return:
1275 * 0 - Success
1276 * Non-zero - Failure
1277 */
1278static long ibmvmc_ioctl_query(struct ibmvmc_file_session *session,
1279 struct ibmvmc_query_struct __user *ret_struct)
1280{
1281 struct ibmvmc_query_struct query_struct;
1282 size_t bytes;
1283
1284 memset(&query_struct, 0, sizeof(query_struct));
1285 query_struct.have_vmc = (ibmvmc.state > ibmvmc_state_initial);
1286 query_struct.state = ibmvmc.state;
1287 query_struct.vmc_drc_index = ibmvmc.vmc_drc_index;
1288
1289 bytes = copy_to_user(ret_struct, &query_struct,
1290 sizeof(query_struct));
1291 if (bytes)
1292 return -EFAULT;
1293
1294 return 0;
1295}
1296
1297/**
1298 * ibmvmc_ioctl_requestvmc - IOCTL Request VMC
1299 *
1300 * @session: ibmvmc_file_session struct
1301 * @ret_vmc_index: VMC Index
1302 *
1303 * Return:
1304 * 0 - Success
1305 * Non-zero - Failure
1306 */
1307static long ibmvmc_ioctl_requestvmc(struct ibmvmc_file_session *session,
1308 u32 __user *ret_vmc_index)
1309{
1310 /* TODO: (adreznec) Add locking to control multiple process access */
1311 size_t bytes;
1312 long rc;
1313 u32 vmc_drc_index;
1314
1315 /* Call to request the VMC device from phyp*/
1316 rc = h_request_vmc(&vmc_drc_index);
1317 pr_debug("ibmvmc: requestvmc: H_REQUEST_VMC rc = 0x%lx\n", rc);
1318
1319 if (rc == H_SUCCESS) {
1320 rc = 0;
1321 } else if (rc == H_FUNCTION) {
1322 pr_err("ibmvmc: requestvmc: h_request_vmc not supported\n");
1323 return -EPERM;
1324 } else if (rc == H_AUTHORITY) {
1325 pr_err("ibmvmc: requestvmc: hypervisor denied vmc request\n");
1326 return -EPERM;
1327 } else if (rc == H_HARDWARE) {
1328 pr_err("ibmvmc: requestvmc: hypervisor hardware fault\n");
1329 return -EIO;
1330 } else if (rc == H_RESOURCE) {
1331 pr_err("ibmvmc: requestvmc: vmc resource unavailable\n");
1332 return -ENODEV;
1333 } else if (rc == H_NOT_AVAILABLE) {
1334 pr_err("ibmvmc: requestvmc: system cannot be vmc managed\n");
1335 return -EPERM;
1336 } else if (rc == H_PARAMETER) {
1337 pr_err("ibmvmc: requestvmc: invalid parameter\n");
1338 return -EINVAL;
1339 }
1340
1341 /* Success, set the vmc index in global struct */
1342 ibmvmc.vmc_drc_index = vmc_drc_index;
1343
1344 bytes = copy_to_user(ret_vmc_index, &vmc_drc_index,
1345 sizeof(*ret_vmc_index));
1346 if (bytes) {
1347 pr_warn("ibmvmc: requestvmc: copy to user failed.\n");
1348 return -EFAULT;
1349 }
1350 return rc;
1351}
1352
1353/**
1354 * ibmvmc_ioctl - IOCTL
1355 *
1356 * @file: file information
1357 * @cmd: cmd field
1358 * @arg: Argument field
1359 *
1360 * Return:
1361 * 0 - Success
1362 * Non-zero - Failure
1363 */
1364static long ibmvmc_ioctl(struct file *file,
1365 unsigned int cmd, unsigned long arg)
1366{
1367 struct ibmvmc_file_session *session = file->private_data;
1368
1369 pr_debug("ibmvmc: ioctl file=0x%lx, cmd=0x%x, arg=0x%lx, ses=0x%lx\n",
1370 (unsigned long)file, cmd, arg,
1371 (unsigned long)session);
1372
1373 if (!session) {
1374 pr_warn("ibmvmc: ioctl: no session\n");
1375 return -EIO;
1376 }
1377
1378 switch (cmd) {
1379 case VMC_IOCTL_SETHMCID:
1380 return ibmvmc_ioctl_sethmcid(session,
1381 (unsigned char __user *)arg);
1382 case VMC_IOCTL_QUERY:
1383 return ibmvmc_ioctl_query(session,
1384 (struct ibmvmc_query_struct __user *)arg);
1385 case VMC_IOCTL_REQUESTVMC:
1386 return ibmvmc_ioctl_requestvmc(session,
1387 (unsigned int __user *)arg);
1388 default:
1389 pr_warn("ibmvmc: unknown ioctl 0x%x\n", cmd);
1390 return -EINVAL;
1391 }
1392}
1393
1394static const struct file_operations ibmvmc_fops = {
1395 .owner = THIS_MODULE,
1396 .read = ibmvmc_read,
1397 .write = ibmvmc_write,
1398 .poll = ibmvmc_poll,
1399 .unlocked_ioctl = ibmvmc_ioctl,
1400 .open = ibmvmc_open,
1401 .release = ibmvmc_close,
1402};
1403
1404/**
1405 * ibmvmc_add_buffer - Add Buffer
1406 *
1407 * @adapter: crq_server_adapter struct
1408 * @crq: ibmvmc_crq_msg struct
1409 *
1410 * This message transfers a buffer from hypervisor ownership to management
1411 * partition ownership. The LIOBA is obtained from the virtual TCE table
1412 * associated with the hypervisor side of the VMC device, and points to a
1413 * buffer of size MTU (as established in the capabilities exchange).
1414 *
1415 * Typical flow for ading buffers:
1416 * 1. A new management application connection is opened by the management
1417 * partition.
1418 * 2. The hypervisor assigns new buffers for the traffic associated with
1419 * that connection.
1420 * 3. The hypervisor sends VMC Add Buffer messages to the management
1421 * partition, informing it of the new buffers.
1422 * 4. The hypervisor sends an HMC protocol message (to the management
1423 * application) notifying it of the new buffers. This informs the
1424 * application that it has buffers available for sending HMC
1425 * commands.
1426 *
1427 * Return:
1428 * 0 - Success
1429 * Non-zero - Failure
1430 */
1431static int ibmvmc_add_buffer(struct crq_server_adapter *adapter,
1432 struct ibmvmc_crq_msg *crq)
1433{
1434 struct ibmvmc_buffer *buffer;
1435 u8 hmc_index;
1436 u8 hmc_session;
1437 u16 buffer_id;
1438 unsigned long flags;
1439 int rc = 0;
1440
1441 if (!crq)
1442 return -1;
1443
1444 hmc_session = crq->hmc_session;
1445 hmc_index = crq->hmc_index;
1446 buffer_id = be16_to_cpu(crq->var2.buffer_id);
1447
1448 if (hmc_index > ibmvmc.max_hmc_index) {
1449 dev_err(adapter->dev, "add_buffer: invalid hmc_index = 0x%x\n",
1450 hmc_index);
1451 ibmvmc_send_add_buffer_resp(adapter, VMC_MSG_INVALID_HMC_INDEX,
1452 hmc_session, hmc_index, buffer_id);
1453 return -1;
1454 }
1455
1456 if (buffer_id >= ibmvmc.max_buffer_pool_size) {
1457 dev_err(adapter->dev, "add_buffer: invalid buffer_id = 0x%x\n",
1458 buffer_id);
1459 ibmvmc_send_add_buffer_resp(adapter, VMC_MSG_INVALID_BUFFER_ID,
1460 hmc_session, hmc_index, buffer_id);
1461 return -1;
1462 }
1463
1464 spin_lock_irqsave(&hmcs[hmc_index].lock, flags);
1465 buffer = &hmcs[hmc_index].buffer[buffer_id];
1466
1467 if (buffer->real_addr_local || buffer->dma_addr_local) {
1468 dev_warn(adapter->dev, "add_buffer: already allocated id = 0x%lx\n",
1469 (unsigned long)buffer_id);
1470 spin_unlock_irqrestore(&hmcs[hmc_index].lock, flags);
1471 ibmvmc_send_add_buffer_resp(adapter, VMC_MSG_INVALID_BUFFER_ID,
1472 hmc_session, hmc_index, buffer_id);
1473 return -1;
1474 }
1475
1476 buffer->real_addr_local = alloc_dma_buffer(to_vio_dev(adapter->dev),
1477 ibmvmc.max_mtu,
1478 &buffer->dma_addr_local);
1479
1480 if (!buffer->real_addr_local) {
1481 dev_err(adapter->dev, "add_buffer: alloc_dma_buffer failed.\n");
1482 spin_unlock_irqrestore(&hmcs[hmc_index].lock, flags);
1483 ibmvmc_send_add_buffer_resp(adapter, VMC_MSG_INTERFACE_FAILURE,
1484 hmc_session, hmc_index, buffer_id);
1485 return -1;
1486 }
1487
1488 buffer->dma_addr_remote = be32_to_cpu(crq->var3.lioba);
1489 buffer->size = ibmvmc.max_mtu;
1490 buffer->owner = crq->var1.owner;
1491 buffer->free = 1;
1492 /* Must ensure valid==1 is observable only after all other fields are */
1493 dma_wmb();
1494 buffer->valid = 1;
1495 buffer->id = buffer_id;
1496
1497 dev_dbg(adapter->dev, "add_buffer: successfully added a buffer:\n");
1498 dev_dbg(adapter->dev, " index: %d, session: %d, buffer: 0x%x, owner: %d\n",
1499 hmc_index, hmc_session, buffer_id, buffer->owner);
1500 dev_dbg(adapter->dev, " local: 0x%x, remote: 0x%x\n",
1501 (u32)buffer->dma_addr_local,
1502 (u32)buffer->dma_addr_remote);
1503 spin_unlock_irqrestore(&hmcs[hmc_index].lock, flags);
1504
1505 ibmvmc_send_add_buffer_resp(adapter, VMC_MSG_SUCCESS, hmc_session,
1506 hmc_index, buffer_id);
1507
1508 return rc;
1509}
1510
1511/**
1512 * ibmvmc_rem_buffer - Remove Buffer
1513 *
1514 * @adapter: crq_server_adapter struct
1515 * @crq: ibmvmc_crq_msg struct
1516 *
1517 * This message requests an HMC buffer to be transferred from management
1518 * partition ownership to hypervisor ownership. The management partition may
1519 * not be able to satisfy the request at a particular point in time if all its
1520 * buffers are in use. The management partition requires a depth of at least
1521 * one inbound buffer to allow management application commands to flow to the
1522 * hypervisor. It is, therefore, an interface error for the hypervisor to
1523 * attempt to remove the management partition's last buffer.
1524 *
1525 * The hypervisor is expected to manage buffer usage with the management
1526 * application directly and inform the management partition when buffers may be
1527 * removed. The typical flow for removing buffers:
1528 *
1529 * 1. The management application no longer needs a communication path to a
1530 * particular hypervisor function. That function is closed.
1531 * 2. The hypervisor and the management application quiesce all traffic to that
1532 * function. The hypervisor requests a reduction in buffer pool size.
1533 * 3. The management application acknowledges the reduction in buffer pool size.
1534 * 4. The hypervisor sends a Remove Buffer message to the management partition,
1535 * informing it of the reduction in buffers.
1536 * 5. The management partition verifies it can remove the buffer. This is
1537 * possible if buffers have been quiesced.
1538 *
1539 * Return:
1540 * 0 - Success
1541 * Non-zero - Failure
1542 */
1543/*
1544 * The hypervisor requested that we pick an unused buffer, and return it.
1545 * Before sending the buffer back, we free any storage associated with the
1546 * buffer.
1547 */
1548static int ibmvmc_rem_buffer(struct crq_server_adapter *adapter,
1549 struct ibmvmc_crq_msg *crq)
1550{
1551 struct ibmvmc_buffer *buffer;
1552 u8 hmc_index;
1553 u8 hmc_session;
1554 u16 buffer_id = 0;
1555 unsigned long flags;
1556 int rc = 0;
1557
1558 if (!crq)
1559 return -1;
1560
1561 hmc_session = crq->hmc_session;
1562 hmc_index = crq->hmc_index;
1563
1564 if (hmc_index > ibmvmc.max_hmc_index) {
1565 dev_warn(adapter->dev, "rem_buffer: invalid hmc_index = 0x%x\n",
1566 hmc_index);
1567 ibmvmc_send_rem_buffer_resp(adapter, VMC_MSG_INVALID_HMC_INDEX,
1568 hmc_session, hmc_index, buffer_id);
1569 return -1;
1570 }
1571
1572 spin_lock_irqsave(&hmcs[hmc_index].lock, flags);
1573 buffer = ibmvmc_get_free_hmc_buffer(adapter, hmc_index);
1574 if (!buffer) {
1575 dev_info(adapter->dev, "rem_buffer: no buffer to remove\n");
1576 spin_unlock_irqrestore(&hmcs[hmc_index].lock, flags);
1577 ibmvmc_send_rem_buffer_resp(adapter, VMC_MSG_NO_BUFFER,
1578 hmc_session, hmc_index,
1579 VMC_INVALID_BUFFER_ID);
1580 return -1;
1581 }
1582
1583 buffer_id = buffer->id;
1584
1585 if (buffer->valid)
1586 free_dma_buffer(to_vio_dev(adapter->dev),
1587 ibmvmc.max_mtu,
1588 buffer->real_addr_local,
1589 buffer->dma_addr_local);
1590
1591 memset(buffer, 0, sizeof(struct ibmvmc_buffer));
1592 spin_unlock_irqrestore(&hmcs[hmc_index].lock, flags);
1593
1594 dev_dbg(adapter->dev, "rem_buffer: removed buffer 0x%x.\n", buffer_id);
1595 ibmvmc_send_rem_buffer_resp(adapter, VMC_MSG_SUCCESS, hmc_session,
1596 hmc_index, buffer_id);
1597
1598 return rc;
1599}
1600
1601static int ibmvmc_recv_msg(struct crq_server_adapter *adapter,
1602 struct ibmvmc_crq_msg *crq)
1603{
1604 struct ibmvmc_buffer *buffer;
1605 struct ibmvmc_hmc *hmc;
1606 unsigned long msg_len;
1607 u8 hmc_index;
1608 u8 hmc_session;
1609 u16 buffer_id;
1610 unsigned long flags;
1611 int rc = 0;
1612
1613 if (!crq)
1614 return -1;
1615
1616 /* Hypervisor writes CRQs directly into our memory in big endian */
1617 dev_dbg(adapter->dev, "Recv_msg: msg from HV 0x%016llx 0x%016llx\n",
1618 be64_to_cpu(*((unsigned long *)crq)),
1619 be64_to_cpu(*(((unsigned long *)crq) + 1)));
1620
1621 hmc_session = crq->hmc_session;
1622 hmc_index = crq->hmc_index;
1623 buffer_id = be16_to_cpu(crq->var2.buffer_id);
1624 msg_len = be32_to_cpu(crq->var3.msg_len);
1625
1626 if (hmc_index > ibmvmc.max_hmc_index) {
1627 dev_err(adapter->dev, "Recv_msg: invalid hmc_index = 0x%x\n",
1628 hmc_index);
1629 ibmvmc_send_add_buffer_resp(adapter, VMC_MSG_INVALID_HMC_INDEX,
1630 hmc_session, hmc_index, buffer_id);
1631 return -1;
1632 }
1633
1634 if (buffer_id >= ibmvmc.max_buffer_pool_size) {
1635 dev_err(adapter->dev, "Recv_msg: invalid buffer_id = 0x%x\n",
1636 buffer_id);
1637 ibmvmc_send_add_buffer_resp(adapter, VMC_MSG_INVALID_BUFFER_ID,
1638 hmc_session, hmc_index, buffer_id);
1639 return -1;
1640 }
1641
1642 hmc = &hmcs[hmc_index];
1643 spin_lock_irqsave(&hmc->lock, flags);
1644
1645 if (hmc->state == ibmhmc_state_free) {
1646 dev_err(adapter->dev, "Recv_msg: invalid hmc state = 0x%x\n",
1647 hmc->state);
1648 /* HMC connection is not valid (possibly was reset under us). */
1649 spin_unlock_irqrestore(&hmc->lock, flags);
1650 return -1;
1651 }
1652
1653 buffer = &hmc->buffer[buffer_id];
1654
1655 if (buffer->valid == 0 || buffer->owner == VMC_BUF_OWNER_ALPHA) {
1656 dev_err(adapter->dev, "Recv_msg: not valid, or not HV. 0x%x 0x%x\n",
1657 buffer->valid, buffer->owner);
1658 spin_unlock_irqrestore(&hmc->lock, flags);
1659 return -1;
1660 }
1661
1662 if (msg_len > buffer->size) {
1663 dev_err(adapter->dev, "Recv_msg: msg_len 0x%lx exceeds buffer size 0x%x\n",
1664 msg_len, buffer->size);
1665 spin_unlock_irqrestore(&hmc->lock, flags);
1666 return -1;
1667 }
1668
1669 /* RDMA the data into the partition. */
1670 rc = h_copy_rdma(msg_len,
1671 adapter->riobn,
1672 buffer->dma_addr_remote,
1673 adapter->liobn,
1674 buffer->dma_addr_local);
1675
1676 dev_dbg(adapter->dev, "Recv_msg: msg_len = 0x%x, buffer_id = 0x%x, queue_head = 0x%x, hmc_idx = 0x%x\n",
1677 (unsigned int)msg_len, (unsigned int)buffer_id,
1678 (unsigned int)hmc->queue_head, (unsigned int)hmc_index);
1679 buffer->msg_len = msg_len;
1680 buffer->free = 0;
1681 buffer->owner = VMC_BUF_OWNER_ALPHA;
1682
1683 if (rc) {
1684 dev_err(adapter->dev, "Failure in recv_msg: h_copy_rdma = 0x%x\n",
1685 rc);
1686 spin_unlock_irqrestore(&hmc->lock, flags);
1687 return -1;
1688 }
1689
1690 /* Must be locked because read operates on the same data */
1691 hmc->queue_outbound_msgs[hmc->queue_head] = buffer_id;
1692 hmc->queue_head++;
1693 if (hmc->queue_head == ibmvmc_max_buf_pool_size)
1694 hmc->queue_head = 0;
1695
1696 if (hmc->queue_head == hmc->queue_tail)
1697 dev_err(adapter->dev, "outbound buffer queue wrapped.\n");
1698
1699 spin_unlock_irqrestore(&hmc->lock, flags);
1700
1701 wake_up_interruptible(&ibmvmc_read_wait);
1702
1703 return 0;
1704}
1705
1706/**
1707 * ibmvmc_process_capabilities - Process Capabilities
1708 *
1709 * @adapter: crq_server_adapter struct
1710 * @crqp: ibmvmc_crq_msg struct
1711 *
1712 */
1713static void ibmvmc_process_capabilities(struct crq_server_adapter *adapter,
1714 struct ibmvmc_crq_msg *crqp)
1715{
1716 struct ibmvmc_admin_crq_msg *crq = (struct ibmvmc_admin_crq_msg *)crqp;
1717
1718 if ((be16_to_cpu(crq->version) >> 8) !=
1719 (IBMVMC_PROTOCOL_VERSION >> 8)) {
1720 dev_err(adapter->dev, "init failed, incompatible versions 0x%x 0x%x\n",
1721 be16_to_cpu(crq->version),
1722 IBMVMC_PROTOCOL_VERSION);
1723 ibmvmc.state = ibmvmc_state_failed;
1724 return;
1725 }
1726
1727 ibmvmc.max_mtu = min_t(u32, ibmvmc_max_mtu, be32_to_cpu(crq->max_mtu));
1728 ibmvmc.max_buffer_pool_size = min_t(u16, ibmvmc_max_buf_pool_size,
1729 be16_to_cpu(crq->pool_size));
1730 ibmvmc.max_hmc_index = min_t(u8, ibmvmc_max_hmcs, crq->max_hmc) - 1;
1731 ibmvmc.state = ibmvmc_state_ready;
1732
1733 dev_info(adapter->dev, "Capabilities: mtu=0x%x, pool_size=0x%x, max_hmc=0x%x\n",
1734 ibmvmc.max_mtu, ibmvmc.max_buffer_pool_size,
1735 ibmvmc.max_hmc_index);
1736}
1737
1738/**
1739 * ibmvmc_validate_hmc_session - Validate HMC Session
1740 *
1741 * @adapter: crq_server_adapter struct
1742 * @crq: ibmvmc_crq_msg struct
1743 *
1744 * Return:
1745 * 0 - Success
1746 * Non-zero - Failure
1747 */
1748static int ibmvmc_validate_hmc_session(struct crq_server_adapter *adapter,
1749 struct ibmvmc_crq_msg *crq)
1750{
1751 unsigned char hmc_index;
1752
1753 hmc_index = crq->hmc_index;
1754
1755 if (crq->hmc_session == 0)
1756 return 0;
1757
1758 if (hmc_index > ibmvmc.max_hmc_index)
1759 return -1;
1760
1761 if (hmcs[hmc_index].session != crq->hmc_session) {
1762 dev_warn(adapter->dev, "Drop, bad session: expected 0x%x, recv 0x%x\n",
1763 hmcs[hmc_index].session, crq->hmc_session);
1764 return -1;
1765 }
1766
1767 return 0;
1768}
1769
1770/**
1771 * ibmvmc_reset - Reset
1772 *
1773 * @adapter: crq_server_adapter struct
1774 * @xport_event: export_event field
1775 *
1776 * Closes all HMC sessions and conditionally schedules a CRQ reset.
1777 * @xport_event: If true, the partner closed their CRQ; we don't need to reset.
1778 * If false, we need to schedule a CRQ reset.
1779 */
1780static void ibmvmc_reset(struct crq_server_adapter *adapter, bool xport_event)
1781{
1782 int i;
1783
1784 if (ibmvmc.state != ibmvmc_state_sched_reset) {
1785 dev_info(adapter->dev, "*** Reset to initial state.\n");
1786 for (i = 0; i < ibmvmc_max_hmcs; i++)
1787 ibmvmc_return_hmc(&hmcs[i], xport_event);
1788
1789 if (xport_event) {
1790 /* CRQ was closed by the partner. We don't need to do
1791 * anything except set ourself to the correct state to
1792 * handle init msgs.
1793 */
1794 ibmvmc.state = ibmvmc_state_crqinit;
1795 } else {
1796 /* The partner did not close their CRQ - instead, we're
1797 * closing the CRQ on our end. Need to schedule this
1798 * for process context, because CRQ reset may require a
1799 * sleep.
1800 *
1801 * Setting ibmvmc.state here immediately prevents
1802 * ibmvmc_open from completing until the reset
1803 * completes in process context.
1804 */
1805 ibmvmc.state = ibmvmc_state_sched_reset;
1806 dev_dbg(adapter->dev, "Device reset scheduled");
1807 wake_up_interruptible(&adapter->reset_wait_queue);
1808 }
1809 }
1810}
1811
1812/**
1813 * ibmvmc_reset_task - Reset Task
1814 *
1815 * @data: Data field
1816 *
1817 * Performs a CRQ reset of the VMC device in process context.
1818 * NOTE: This function should not be called directly, use ibmvmc_reset.
1819 */
1820static int ibmvmc_reset_task(void *data)
1821{
1822 struct crq_server_adapter *adapter = data;
1823 int rc;
1824
1825 set_user_nice(current, -20);
1826
1827 while (!kthread_should_stop()) {
1828 wait_event_interruptible(adapter->reset_wait_queue,
1829 (ibmvmc.state == ibmvmc_state_sched_reset) ||
1830 kthread_should_stop());
1831
1832 if (kthread_should_stop())
1833 break;
1834
1835 dev_dbg(adapter->dev, "CRQ resetting in process context");
1836 tasklet_disable(&adapter->work_task);
1837
1838 rc = ibmvmc_reset_crq_queue(adapter);
1839
1840 if (rc != H_SUCCESS && rc != H_RESOURCE) {
1841 dev_err(adapter->dev, "Error initializing CRQ. rc = 0x%x\n",
1842 rc);
1843 ibmvmc.state = ibmvmc_state_failed;
1844 } else {
1845 ibmvmc.state = ibmvmc_state_crqinit;
1846
1847 if (ibmvmc_send_crq(adapter, 0xC001000000000000LL, 0)
1848 != 0 && rc != H_RESOURCE)
1849 dev_warn(adapter->dev, "Failed to send initialize CRQ message\n");
1850 }
1851
1852 vio_enable_interrupts(to_vio_dev(adapter->dev));
1853 tasklet_enable(&adapter->work_task);
1854 }
1855
1856 return 0;
1857}
1858
1859/**
1860 * ibmvmc_process_open_resp - Process Open Response
1861 *
1862 * @crq: ibmvmc_crq_msg struct
1863 * @adapter: crq_server_adapter struct
1864 *
1865 * This command is sent by the hypervisor in response to the Interface
1866 * Open message. When this message is received, the indicated buffer is
1867 * again available for management partition use.
1868 */
1869static void ibmvmc_process_open_resp(struct ibmvmc_crq_msg *crq,
1870 struct crq_server_adapter *adapter)
1871{
1872 unsigned char hmc_index;
1873 unsigned short buffer_id;
1874
1875 hmc_index = crq->hmc_index;
1876 if (hmc_index > ibmvmc.max_hmc_index) {
1877 /* Why would PHYP give an index > max negotiated? */
1878 ibmvmc_reset(adapter, false);
1879 return;
1880 }
1881
1882 if (crq->status) {
1883 dev_warn(adapter->dev, "open_resp: failed - status 0x%x\n",
1884 crq->status);
1885 ibmvmc_return_hmc(&hmcs[hmc_index], false);
1886 return;
1887 }
1888
1889 if (hmcs[hmc_index].state == ibmhmc_state_opening) {
1890 buffer_id = be16_to_cpu(crq->var2.buffer_id);
1891 if (buffer_id >= ibmvmc.max_buffer_pool_size) {
1892 dev_err(adapter->dev, "open_resp: invalid buffer_id = 0x%x\n",
1893 buffer_id);
1894 hmcs[hmc_index].state = ibmhmc_state_failed;
1895 } else {
1896 ibmvmc_free_hmc_buffer(&hmcs[hmc_index],
1897 &hmcs[hmc_index].buffer[buffer_id]);
1898 hmcs[hmc_index].state = ibmhmc_state_ready;
1899 dev_dbg(adapter->dev, "open_resp: set hmc state = ready\n");
1900 }
1901 } else {
1902 dev_warn(adapter->dev, "open_resp: invalid hmc state (0x%x)\n",
1903 hmcs[hmc_index].state);
1904 }
1905}
1906
1907/**
1908 * ibmvmc_process_close_resp - Process Close Response
1909 *
1910 * @crq: ibmvmc_crq_msg struct
1911 * @adapter: crq_server_adapter struct
1912 *
1913 * This command is sent by the hypervisor in response to the managemant
1914 * application Interface Close message.
1915 *
1916 * If the close fails, simply reset the entire driver as the state of the VMC
1917 * must be in tough shape.
1918 */
1919static void ibmvmc_process_close_resp(struct ibmvmc_crq_msg *crq,
1920 struct crq_server_adapter *adapter)
1921{
1922 unsigned char hmc_index;
1923
1924 hmc_index = crq->hmc_index;
1925 if (hmc_index > ibmvmc.max_hmc_index) {
1926 ibmvmc_reset(adapter, false);
1927 return;
1928 }
1929
1930 if (crq->status) {
1931 dev_warn(adapter->dev, "close_resp: failed - status 0x%x\n",
1932 crq->status);
1933 ibmvmc_reset(adapter, false);
1934 return;
1935 }
1936
1937 ibmvmc_return_hmc(&hmcs[hmc_index], false);
1938}
1939
1940/**
1941 * ibmvmc_crq_process - Process CRQ
1942 *
1943 * @adapter: crq_server_adapter struct
1944 * @crq: ibmvmc_crq_msg struct
1945 *
1946 * Process the CRQ message based upon the type of message received.
1947 *
1948 */
1949static void ibmvmc_crq_process(struct crq_server_adapter *adapter,
1950 struct ibmvmc_crq_msg *crq)
1951{
1952 switch (crq->type) {
1953 case VMC_MSG_CAP_RESP:
1954 dev_dbg(adapter->dev, "CRQ recv: capabilities resp (0x%x)\n",
1955 crq->type);
1956 if (ibmvmc.state == ibmvmc_state_capabilities)
1957 ibmvmc_process_capabilities(adapter, crq);
1958 else
1959 dev_warn(adapter->dev, "caps msg invalid in state 0x%x\n",
1960 ibmvmc.state);
1961 break;
1962 case VMC_MSG_OPEN_RESP:
1963 dev_dbg(adapter->dev, "CRQ recv: open resp (0x%x)\n",
1964 crq->type);
1965 if (ibmvmc_validate_hmc_session(adapter, crq) == 0)
1966 ibmvmc_process_open_resp(crq, adapter);
1967 break;
1968 case VMC_MSG_ADD_BUF:
1969 dev_dbg(adapter->dev, "CRQ recv: add buf (0x%x)\n",
1970 crq->type);
1971 if (ibmvmc_validate_hmc_session(adapter, crq) == 0)
1972 ibmvmc_add_buffer(adapter, crq);
1973 break;
1974 case VMC_MSG_REM_BUF:
1975 dev_dbg(adapter->dev, "CRQ recv: rem buf (0x%x)\n",
1976 crq->type);
1977 if (ibmvmc_validate_hmc_session(adapter, crq) == 0)
1978 ibmvmc_rem_buffer(adapter, crq);
1979 break;
1980 case VMC_MSG_SIGNAL:
1981 dev_dbg(adapter->dev, "CRQ recv: signal msg (0x%x)\n",
1982 crq->type);
1983 if (ibmvmc_validate_hmc_session(adapter, crq) == 0)
1984 ibmvmc_recv_msg(adapter, crq);
1985 break;
1986 case VMC_MSG_CLOSE_RESP:
1987 dev_dbg(adapter->dev, "CRQ recv: close resp (0x%x)\n",
1988 crq->type);
1989 if (ibmvmc_validate_hmc_session(adapter, crq) == 0)
1990 ibmvmc_process_close_resp(crq, adapter);
1991 break;
1992 case VMC_MSG_CAP:
1993 case VMC_MSG_OPEN:
1994 case VMC_MSG_CLOSE:
1995 case VMC_MSG_ADD_BUF_RESP:
1996 case VMC_MSG_REM_BUF_RESP:
1997 dev_warn(adapter->dev, "CRQ recv: unexpected msg (0x%x)\n",
1998 crq->type);
1999 break;
2000 default:
2001 dev_warn(adapter->dev, "CRQ recv: unknown msg (0x%x)\n",
2002 crq->type);
2003 break;
2004 }
2005}
2006
2007/**
2008 * ibmvmc_handle_crq_init - Handle CRQ Init
2009 *
2010 * @crq: ibmvmc_crq_msg struct
2011 * @adapter: crq_server_adapter struct
2012 *
2013 * Handle the type of crq initialization based on whether
2014 * it is a message or a response.
2015 *
2016 */
2017static void ibmvmc_handle_crq_init(struct ibmvmc_crq_msg *crq,
2018 struct crq_server_adapter *adapter)
2019{
2020 switch (crq->type) {
2021 case 0x01: /* Initialization message */
2022 dev_dbg(adapter->dev, "CRQ recv: CRQ init msg - state 0x%x\n",
2023 ibmvmc.state);
2024 if (ibmvmc.state == ibmvmc_state_crqinit) {
2025 /* Send back a response */
2026 if (ibmvmc_send_crq(adapter, 0xC002000000000000,
2027 0) == 0)
2028 ibmvmc_send_capabilities(adapter);
2029 else
2030 dev_err(adapter->dev, " Unable to send init rsp\n");
2031 } else {
2032 dev_err(adapter->dev, "Invalid state 0x%x mtu = 0x%x\n",
2033 ibmvmc.state, ibmvmc.max_mtu);
2034 }
2035
2036 break;
2037 case 0x02: /* Initialization response */
2038 dev_dbg(adapter->dev, "CRQ recv: initialization resp msg - state 0x%x\n",
2039 ibmvmc.state);
2040 if (ibmvmc.state == ibmvmc_state_crqinit)
2041 ibmvmc_send_capabilities(adapter);
2042 break;
2043 default:
2044 dev_warn(adapter->dev, "Unknown crq message type 0x%lx\n",
2045 (unsigned long)crq->type);
2046 }
2047}
2048
2049/**
2050 * ibmvmc_handle_crq - Handle CRQ
2051 *
2052 * @crq: ibmvmc_crq_msg struct
2053 * @adapter: crq_server_adapter struct
2054 *
2055 * Read the command elements from the command queue and execute the
2056 * requests based upon the type of crq message.
2057 *
2058 */
2059static void ibmvmc_handle_crq(struct ibmvmc_crq_msg *crq,
2060 struct crq_server_adapter *adapter)
2061{
2062 switch (crq->valid) {
2063 case 0xC0: /* initialization */
2064 ibmvmc_handle_crq_init(crq, adapter);
2065 break;
2066 case 0xFF: /* Hypervisor telling us the connection is closed */
2067 dev_warn(adapter->dev, "CRQ recv: virtual adapter failed - resetting.\n");
2068 ibmvmc_reset(adapter, true);
2069 break;
2070 case 0x80: /* real payload */
2071 ibmvmc_crq_process(adapter, crq);
2072 break;
2073 default:
2074 dev_warn(adapter->dev, "CRQ recv: unknown msg 0x%02x.\n",
2075 crq->valid);
2076 break;
2077 }
2078}
2079
2080static void ibmvmc_task(unsigned long data)
2081{
2082 struct crq_server_adapter *adapter =
2083 (struct crq_server_adapter *)data;
2084 struct vio_dev *vdev = to_vio_dev(adapter->dev);
2085 struct ibmvmc_crq_msg *crq;
2086 int done = 0;
2087
2088 while (!done) {
2089 /* Pull all the valid messages off the CRQ */
2090 while ((crq = crq_queue_next_crq(&adapter->queue)) != NULL) {
2091 ibmvmc_handle_crq(crq, adapter);
2092 crq->valid = 0x00;
2093 /* CRQ reset was requested, stop processing CRQs.
2094 * Interrupts will be re-enabled by the reset task.
2095 */
2096 if (ibmvmc.state == ibmvmc_state_sched_reset)
2097 return;
2098 }
2099
2100 vio_enable_interrupts(vdev);
2101 crq = crq_queue_next_crq(&adapter->queue);
2102 if (crq) {
2103 vio_disable_interrupts(vdev);
2104 ibmvmc_handle_crq(crq, adapter);
2105 crq->valid = 0x00;
2106 /* CRQ reset was requested, stop processing CRQs.
2107 * Interrupts will be re-enabled by the reset task.
2108 */
2109 if (ibmvmc.state == ibmvmc_state_sched_reset)
2110 return;
2111 } else {
2112 done = 1;
2113 }
2114 }
2115}
2116
2117/**
2118 * ibmvmc_init_crq_queue - Init CRQ Queue
2119 *
2120 * @adapter: crq_server_adapter struct
2121 *
2122 * Return:
2123 * 0 - Success
2124 * Non-zero - Failure
2125 */
2126static int ibmvmc_init_crq_queue(struct crq_server_adapter *adapter)
2127{
2128 struct vio_dev *vdev = to_vio_dev(adapter->dev);
2129 struct crq_queue *queue = &adapter->queue;
2130 int rc = 0;
2131 int retrc = 0;
2132
2133 queue->msgs = (struct ibmvmc_crq_msg *)get_zeroed_page(GFP_KERNEL);
2134
2135 if (!queue->msgs)
2136 goto malloc_failed;
2137
2138 queue->size = PAGE_SIZE / sizeof(*queue->msgs);
2139
2140 queue->msg_token = dma_map_single(adapter->dev, queue->msgs,
2141 queue->size * sizeof(*queue->msgs),
2142 DMA_BIDIRECTIONAL);
2143
2144 if (dma_mapping_error(adapter->dev, queue->msg_token))
2145 goto map_failed;
2146
2147 retrc = plpar_hcall_norets(H_REG_CRQ,
2148 vdev->unit_address,
2149 queue->msg_token, PAGE_SIZE);
2150 rc = retrc;
2151
2152 if (rc == H_RESOURCE)
2153 rc = ibmvmc_reset_crq_queue(adapter);
2154
2155 if (rc == 2) {
2156 dev_warn(adapter->dev, "Partner adapter not ready\n");
2157 retrc = 0;
2158 } else if (rc != 0) {
2159 dev_err(adapter->dev, "Error %d opening adapter\n", rc);
2160 goto reg_crq_failed;
2161 }
2162
2163 queue->cur = 0;
2164 spin_lock_init(&queue->lock);
2165
2166 tasklet_init(&adapter->work_task, ibmvmc_task, (unsigned long)adapter);
2167
2168 if (request_irq(vdev->irq,
2169 ibmvmc_handle_event,
2170 0, "ibmvmc", (void *)adapter) != 0) {
2171 dev_err(adapter->dev, "couldn't register irq 0x%x\n",
2172 vdev->irq);
2173 goto req_irq_failed;
2174 }
2175
2176 rc = vio_enable_interrupts(vdev);
2177 if (rc != 0) {
2178 dev_err(adapter->dev, "Error %d enabling interrupts!!!\n", rc);
2179 goto req_irq_failed;
2180 }
2181
2182 return retrc;
2183
2184req_irq_failed:
2185 /* Cannot have any work since we either never got our IRQ registered,
2186 * or never got interrupts enabled
2187 */
2188 tasklet_kill(&adapter->work_task);
2189 h_free_crq(vdev->unit_address);
2190reg_crq_failed:
2191 dma_unmap_single(adapter->dev,
2192 queue->msg_token,
2193 queue->size * sizeof(*queue->msgs), DMA_BIDIRECTIONAL);
2194map_failed:
2195 free_page((unsigned long)queue->msgs);
2196malloc_failed:
2197 return -ENOMEM;
2198}
2199
2200/* Fill in the liobn and riobn fields on the adapter */
2201static int read_dma_window(struct vio_dev *vdev,
2202 struct crq_server_adapter *adapter)
2203{
2204 const __be32 *dma_window;
2205 const __be32 *prop;
2206
2207 /* TODO Using of_parse_dma_window would be better, but it doesn't give
2208 * a way to read multiple windows without already knowing the size of
2209 * a window or the number of windows
2210 */
2211 dma_window =
2212 (const __be32 *)vio_get_attribute(vdev, "ibm,my-dma-window",
2213 NULL);
2214 if (!dma_window) {
2215 dev_warn(adapter->dev, "Couldn't find ibm,my-dma-window property\n");
2216 return -1;
2217 }
2218
2219 adapter->liobn = be32_to_cpu(*dma_window);
2220 dma_window++;
2221
2222 prop = (const __be32 *)vio_get_attribute(vdev, "ibm,#dma-address-cells",
2223 NULL);
2224 if (!prop) {
2225 dev_warn(adapter->dev, "Couldn't find ibm,#dma-address-cells property\n");
2226 dma_window++;
2227 } else {
2228 dma_window += be32_to_cpu(*prop);
2229 }
2230
2231 prop = (const __be32 *)vio_get_attribute(vdev, "ibm,#dma-size-cells",
2232 NULL);
2233 if (!prop) {
2234 dev_warn(adapter->dev, "Couldn't find ibm,#dma-size-cells property\n");
2235 dma_window++;
2236 } else {
2237 dma_window += be32_to_cpu(*prop);
2238 }
2239
2240 /* dma_window should point to the second window now */
2241 adapter->riobn = be32_to_cpu(*dma_window);
2242
2243 return 0;
2244}
2245
2246static int ibmvmc_probe(struct vio_dev *vdev, const struct vio_device_id *id)
2247{
2248 struct crq_server_adapter *adapter = &ibmvmc_adapter;
2249 int rc;
2250
2251 dev_set_drvdata(&vdev->dev, NULL);
2252 memset(adapter, 0, sizeof(*adapter));
2253 adapter->dev = &vdev->dev;
2254
2255 dev_info(adapter->dev, "Probe for UA 0x%x\n", vdev->unit_address);
2256
2257 rc = read_dma_window(vdev, adapter);
2258 if (rc != 0) {
2259 ibmvmc.state = ibmvmc_state_failed;
2260 return -1;
2261 }
2262
2263 dev_dbg(adapter->dev, "Probe: liobn 0x%x, riobn 0x%x\n",
2264 adapter->liobn, adapter->riobn);
2265
2266 init_waitqueue_head(&adapter->reset_wait_queue);
2267 adapter->reset_task = kthread_run(ibmvmc_reset_task, adapter, "ibmvmc");
2268 if (IS_ERR(adapter->reset_task)) {
2269 dev_err(adapter->dev, "Failed to start reset thread\n");
2270 ibmvmc.state = ibmvmc_state_failed;
2271 rc = PTR_ERR(adapter->reset_task);
2272 adapter->reset_task = NULL;
2273 return rc;
2274 }
2275
2276 rc = ibmvmc_init_crq_queue(adapter);
2277 if (rc != 0 && rc != H_RESOURCE) {
2278 dev_err(adapter->dev, "Error initializing CRQ. rc = 0x%x\n",
2279 rc);
2280 ibmvmc.state = ibmvmc_state_failed;
2281 goto crq_failed;
2282 }
2283
2284 ibmvmc.state = ibmvmc_state_crqinit;
2285
2286 /* Try to send an initialization message. Note that this is allowed
2287 * to fail if the other end is not acive. In that case we just wait
2288 * for the other side to initialize.
2289 */
2290 if (ibmvmc_send_crq(adapter, 0xC001000000000000LL, 0) != 0 &&
2291 rc != H_RESOURCE)
2292 dev_warn(adapter->dev, "Failed to send initialize CRQ message\n");
2293
2294 dev_set_drvdata(&vdev->dev, adapter);
2295
2296 return 0;
2297
2298crq_failed:
2299 kthread_stop(adapter->reset_task);
2300 adapter->reset_task = NULL;
2301 return -EPERM;
2302}
2303
2304static void ibmvmc_remove(struct vio_dev *vdev)
2305{
2306 struct crq_server_adapter *adapter = dev_get_drvdata(&vdev->dev);
2307
2308 dev_info(adapter->dev, "Entering remove for UA 0x%x\n",
2309 vdev->unit_address);
2310 ibmvmc_release_crq_queue(adapter);
2311}
2312
2313static struct vio_device_id ibmvmc_device_table[] = {
2314 { .type = "ibm,vmc", .compat = "IBM,vmc" },
2315 { }
2316};
2317MODULE_DEVICE_TABLE(vio, ibmvmc_device_table);
2318
2319static struct vio_driver ibmvmc_driver = {
2320 .name = ibmvmc_driver_name,
2321 .id_table = ibmvmc_device_table,
2322 .probe = ibmvmc_probe,
2323 .remove = ibmvmc_remove,
2324};
2325
2326static void __init ibmvmc_scrub_module_parms(void)
2327{
2328 if (ibmvmc_max_mtu > MAX_MTU) {
2329 pr_warn("ibmvmc: Max MTU reduced to %d\n", MAX_MTU);
2330 ibmvmc_max_mtu = MAX_MTU;
2331 } else if (ibmvmc_max_mtu < MIN_MTU) {
2332 pr_warn("ibmvmc: Max MTU increased to %d\n", MIN_MTU);
2333 ibmvmc_max_mtu = MIN_MTU;
2334 }
2335
2336 if (ibmvmc_max_buf_pool_size > MAX_BUF_POOL_SIZE) {
2337 pr_warn("ibmvmc: Max buffer pool size reduced to %d\n",
2338 MAX_BUF_POOL_SIZE);
2339 ibmvmc_max_buf_pool_size = MAX_BUF_POOL_SIZE;
2340 } else if (ibmvmc_max_buf_pool_size < MIN_BUF_POOL_SIZE) {
2341 pr_warn("ibmvmc: Max buffer pool size increased to %d\n",
2342 MIN_BUF_POOL_SIZE);
2343 ibmvmc_max_buf_pool_size = MIN_BUF_POOL_SIZE;
2344 }
2345
2346 if (ibmvmc_max_hmcs > MAX_HMCS) {
2347 pr_warn("ibmvmc: Max HMCs reduced to %d\n", MAX_HMCS);
2348 ibmvmc_max_hmcs = MAX_HMCS;
2349 } else if (ibmvmc_max_hmcs < MIN_HMCS) {
2350 pr_warn("ibmvmc: Max HMCs increased to %d\n", MIN_HMCS);
2351 ibmvmc_max_hmcs = MIN_HMCS;
2352 }
2353}
2354
2355static struct miscdevice ibmvmc_miscdev = {
2356 .name = ibmvmc_driver_name,
2357 .minor = MISC_DYNAMIC_MINOR,
2358 .fops = &ibmvmc_fops,
2359};
2360
2361static int __init ibmvmc_module_init(void)
2362{
2363 int rc, i, j;
2364
2365 ibmvmc.state = ibmvmc_state_initial;
2366 pr_info("ibmvmc: version %s\n", IBMVMC_DRIVER_VERSION);
2367
2368 rc = misc_register(&ibmvmc_miscdev);
2369 if (rc) {
2370 pr_err("ibmvmc: misc registration failed\n");
2371 goto misc_register_failed;
2372 }
2373 pr_info("ibmvmc: node %d:%d\n", MISC_MAJOR,
2374 ibmvmc_miscdev.minor);
2375
2376 /* Initialize data structures */
2377 memset(hmcs, 0, sizeof(struct ibmvmc_hmc) * MAX_HMCS);
2378 for (i = 0; i < MAX_HMCS; i++) {
2379 spin_lock_init(&hmcs[i].lock);
2380 hmcs[i].state = ibmhmc_state_free;
2381 for (j = 0; j < MAX_BUF_POOL_SIZE; j++)
2382 hmcs[i].queue_outbound_msgs[j] = VMC_INVALID_BUFFER_ID;
2383 }
2384
2385 /* Sanity check module parms */
2386 ibmvmc_scrub_module_parms();
2387
2388 /*
2389 * Initialize some reasonable values. Might be negotiated smaller
2390 * values during the capabilities exchange.
2391 */
2392 ibmvmc.max_mtu = ibmvmc_max_mtu;
2393 ibmvmc.max_buffer_pool_size = ibmvmc_max_buf_pool_size;
2394 ibmvmc.max_hmc_index = ibmvmc_max_hmcs - 1;
2395
2396 rc = vio_register_driver(&ibmvmc_driver);
2397
2398 if (rc) {
2399 pr_err("ibmvmc: rc %d from vio_register_driver\n", rc);
2400 goto vio_reg_failed;
2401 }
2402
2403 return 0;
2404
2405vio_reg_failed:
2406 misc_deregister(&ibmvmc_miscdev);
2407misc_register_failed:
2408 return rc;
2409}
2410
2411static void __exit ibmvmc_module_exit(void)
2412{
2413 pr_info("ibmvmc: module exit\n");
2414 vio_unregister_driver(&ibmvmc_driver);
2415 misc_deregister(&ibmvmc_miscdev);
2416}
2417
2418module_init(ibmvmc_module_init);
2419module_exit(ibmvmc_module_exit);
2420
2421module_param_named(buf_pool_size, ibmvmc_max_buf_pool_size,
2422 int, 0644);
2423MODULE_PARM_DESC(buf_pool_size, "Buffer pool size");
2424module_param_named(max_hmcs, ibmvmc_max_hmcs, int, 0644);
2425MODULE_PARM_DESC(max_hmcs, "Max HMCs");
2426module_param_named(max_mtu, ibmvmc_max_mtu, int, 0644);
2427MODULE_PARM_DESC(max_mtu, "Max MTU");
2428
2429MODULE_AUTHOR("Steven Royer <[email protected]>");
2430MODULE_DESCRIPTION("IBM VMC");
2431MODULE_VERSION(IBMVMC_DRIVER_VERSION);
2432MODULE_LICENSE("GPL v2");