viopath.c 18.5 KB
Newer Older
Linus Torvalds's avatar
Linus Torvalds committed
1 2 3 4 5 6 7 8
/* -*- linux-c -*-
 *
 *  iSeries Virtual I/O Message Path code
 *
 *  Authors: Dave Boutcher <boutcher@us.ibm.com>
 *           Ryan Arnold <ryanarn@us.ibm.com>
 *           Colin Devilbiss <devilbis@us.ibm.com>
 *
9
 * (C) Copyright 2000-2005 IBM Corporation
Linus Torvalds's avatar
Linus Torvalds committed
10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39
 *
 * This code is used by the iSeries virtual disk, cd,
 * tape, and console to communicate with OS/400 in another
 * partition.
 *
 * This program is free software;  you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2 of the
 * License, or (at your option) anyu later version.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software Foundation,
 * Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 *
 */
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/vmalloc.h>
#include <linux/string.h>
#include <linux/proc_fs.h>
#include <linux/dma-mapping.h>
#include <linux/wait.h>
#include <linux/seq_file.h>
#include <linux/interrupt.h>
40
#include <linux/completion.h>
Linus Torvalds's avatar
Linus Torvalds committed
41 42 43

#include <asm/system.h>
#include <asm/uaccess.h>
44
#include <asm/prom.h>
45
#include <asm/firmware.h>
46
#include <asm/iseries/hv_types.h>
47
#include <asm/iseries/hv_lp_event.h>
48
#include <asm/iseries/hv_lp_config.h>
49
#include <asm/iseries/mf.h>
50
#include <asm/iseries/vio.h>
Linus Torvalds's avatar
Linus Torvalds committed
51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71

/* Status of the path to each other partition in the system.
 * This is overkill, since we will only ever establish connections
 * to our hosting partition and the primary partition on the system.
 * But this allows for other support in the future.
 */
static struct viopathStatus {
	int isOpen;		/* Did we open the path?            */
	int isActive;		/* Do we have a mon msg outstanding */
	int users[VIO_MAX_SUBTYPES];
	HvLpInstanceId mSourceInst;
	HvLpInstanceId mTargetInst;
	int numberAllocated;
} viopathStatus[HVMAXARCHITECTEDLPS];

static DEFINE_SPINLOCK(statuslock);

/*
 * For each kind of event we allocate a buffer that is
 * guaranteed not to cross a page boundary
 */
72 73
static unsigned char event_buffer[VIO_MAX_SUBTYPES * 256]
	__attribute__((__aligned__(4096)));
Linus Torvalds's avatar
Linus Torvalds committed
74 75 76 77 78 79 80 81 82 83 84
static atomic_t event_buffer_available[VIO_MAX_SUBTYPES];
static int event_buffer_initialised;

static void handleMonitorEvent(struct HvLpEvent *event);

/*
 * We use this structure to handle asynchronous responses.  The caller
 * blocks on the semaphore and the handler posts the semaphore.  However,
 * if system_state is not SYSTEM_RUNNING, then wait_atomic is used ...
 */
struct alloc_parms {
85
	struct completion done;
Linus Torvalds's avatar
Linus Torvalds committed
86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118
	int number;
	atomic_t wait_atomic;
	int used_wait_atomic;
};

/* Put a sequence number in each mon msg.  The value is not
 * important.  Start at something other than 0 just for
 * readability.  wrapping this is ok.
 */
static u8 viomonseq = 22;

/* Our hosting logical partition.  We get this at startup
 * time, and different modules access this variable directly.
 */
HvLpIndex viopath_hostLp = HvLpIndexInvalid;
EXPORT_SYMBOL(viopath_hostLp);
HvLpIndex viopath_ourLp = HvLpIndexInvalid;
EXPORT_SYMBOL(viopath_ourLp);

/* For each kind of incoming event we set a pointer to a
 * routine to call.
 */
static vio_event_handler_t *vio_handler[VIO_MAX_SUBTYPES];

#define VIOPATH_KERN_WARN	KERN_WARNING "viopath: "
#define VIOPATH_KERN_INFO	KERN_INFO "viopath: "

static int proc_viopath_show(struct seq_file *m, void *v)
{
	char *buf;
	u16 vlanMap;
	dma_addr_t handle;
	HvLpEvent_Rc hvrc;
119
	DECLARE_COMPLETION(done);
120
	struct device_node *node;
121
	const char *sysid;
Linus Torvalds's avatar
Linus Torvalds committed
122

123
	buf = kzalloc(HW_PAGE_SIZE, GFP_KERNEL);
Linus Torvalds's avatar
Linus Torvalds committed
124 125 126
	if (!buf)
		return 0;

127
	handle = dma_map_single(iSeries_vio_dev, buf, HW_PAGE_SIZE,
Linus Torvalds's avatar
Linus Torvalds committed
128 129 130 131 132 133 134 135
				DMA_FROM_DEVICE);

	hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
			HvLpEvent_Type_VirtualIo,
			viomajorsubtype_config | vioconfigget,
			HvLpEvent_AckInd_DoAck, HvLpEvent_AckType_ImmediateAck,
			viopath_sourceinst(viopath_hostLp),
			viopath_targetinst(viopath_hostLp),
136
			(u64)(unsigned long)&done, VIOVERSION << 16,
137
			((u64)handle) << 32, HW_PAGE_SIZE, 0, 0);
Linus Torvalds's avatar
Linus Torvalds committed
138 139 140 141

	if (hvrc != HvLpEvent_Rc_Good)
		printk(VIOPATH_KERN_WARN "hv error on op %d\n", (int)hvrc);

142
	wait_for_completion(&done);
Linus Torvalds's avatar
Linus Torvalds committed
143 144 145

	vlanMap = HvLpConfig_getVirtualLanIndexMap();

146
	buf[HW_PAGE_SIZE-1] = '\0';
Linus Torvalds's avatar
Linus Torvalds committed
147 148
	seq_printf(m, "%s", buf);

149 150
	dma_unmap_single(iSeries_vio_dev, handle, HW_PAGE_SIZE,
			 DMA_FROM_DEVICE);
Linus Torvalds's avatar
Linus Torvalds committed
151 152
	kfree(buf);

153 154 155
	seq_printf(m, "AVAILABLE_VETH=%x\n", vlanMap);

	node = of_find_node_by_path("/");
156
	sysid = NULL;
157
	if (node != NULL)
158
		sysid = of_get_property(node, "system-id", NULL);
159

160
	if (sysid == NULL)
161 162 163
		seq_printf(m, "SRLNBR=<UNKNOWN>\n");
	else
		/* Skip "IBM," on front of serial number, see dt.c */
164
		seq_printf(m, "SRLNBR=%s\n", sysid + 4);
165 166 167

	of_node_put(node);

Linus Torvalds's avatar
Linus Torvalds committed
168 169 170 171 172 173 174 175
	return 0;
}

static int proc_viopath_open(struct inode *inode, struct file *file)
{
	return single_open(file, proc_viopath_show, NULL);
}

176
static const struct file_operations proc_viopath_operations = {
Linus Torvalds's avatar
Linus Torvalds committed
177 178 179 180 181 182 183 184 185 186
	.open		= proc_viopath_open,
	.read		= seq_read,
	.llseek		= seq_lseek,
	.release	= single_release,
};

static int __init vio_proc_init(void)
{
	struct proc_dir_entry *e;

187 188 189
	if (!firmware_has_feature(FW_FEATURE_ISERIES))
		return 0;

Linus Torvalds's avatar
Linus Torvalds committed
190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283
	e = create_proc_entry("iSeries/config", 0, NULL);
	if (e)
		e->proc_fops = &proc_viopath_operations;

        return 0;
}
__initcall(vio_proc_init);

/* See if a given LP is active.  Allow for invalid lps to be passed in
 * and just return invalid
 */
int viopath_isactive(HvLpIndex lp)
{
	if (lp == HvLpIndexInvalid)
		return 0;
	if (lp < HVMAXARCHITECTEDLPS)
		return viopathStatus[lp].isActive;
	else
		return 0;
}
EXPORT_SYMBOL(viopath_isactive);

/*
 * We cache the source and target instance ids for each
 * partition.
 */
HvLpInstanceId viopath_sourceinst(HvLpIndex lp)
{
	return viopathStatus[lp].mSourceInst;
}
EXPORT_SYMBOL(viopath_sourceinst);

HvLpInstanceId viopath_targetinst(HvLpIndex lp)
{
	return viopathStatus[lp].mTargetInst;
}
EXPORT_SYMBOL(viopath_targetinst);

/*
 * Send a monitor message.  This is a message with the acknowledge
 * bit on that the other side will NOT explicitly acknowledge.  When
 * the other side goes down, the hypervisor will acknowledge any
 * outstanding messages....so we will know when the other side dies.
 */
static void sendMonMsg(HvLpIndex remoteLp)
{
	HvLpEvent_Rc hvrc;

	viopathStatus[remoteLp].mSourceInst =
		HvCallEvent_getSourceLpInstanceId(remoteLp,
				HvLpEvent_Type_VirtualIo);
	viopathStatus[remoteLp].mTargetInst =
		HvCallEvent_getTargetLpInstanceId(remoteLp,
				HvLpEvent_Type_VirtualIo);

	/*
	 * Deliberately ignore the return code here.  if we call this
	 * more than once, we don't care.
	 */
	vio_setHandler(viomajorsubtype_monitor, handleMonitorEvent);

	hvrc = HvCallEvent_signalLpEventFast(remoteLp, HvLpEvent_Type_VirtualIo,
			viomajorsubtype_monitor, HvLpEvent_AckInd_DoAck,
			HvLpEvent_AckType_DeferredAck,
			viopathStatus[remoteLp].mSourceInst,
			viopathStatus[remoteLp].mTargetInst,
			viomonseq++, 0, 0, 0, 0, 0);

	if (hvrc == HvLpEvent_Rc_Good)
		viopathStatus[remoteLp].isActive = 1;
	else {
		printk(VIOPATH_KERN_WARN "could not connect to partition %d\n",
				remoteLp);
		viopathStatus[remoteLp].isActive = 0;
	}
}

static void handleMonitorEvent(struct HvLpEvent *event)
{
	HvLpIndex remoteLp;
	int i;

	/*
	 * This handler is _also_ called as part of the loop
	 * at the end of this routine, so it must be able to
	 * ignore NULL events...
	 */
	if (!event)
		return;

	/*
	 * First see if this is just a normal monitor message from the
	 * other partition
	 */
284
	if (hvlpevent_is_int(event)) {
Linus Torvalds's avatar
Linus Torvalds committed
285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344
		remoteLp = event->xSourceLp;
		if (!viopathStatus[remoteLp].isActive)
			sendMonMsg(remoteLp);
		return;
	}

	/*
	 * This path is for an acknowledgement; the other partition
	 * died
	 */
	remoteLp = event->xTargetLp;
	if ((event->xSourceInstanceId != viopathStatus[remoteLp].mSourceInst) ||
	    (event->xTargetInstanceId != viopathStatus[remoteLp].mTargetInst)) {
		printk(VIOPATH_KERN_WARN "ignoring ack....mismatched instances\n");
		return;
	}

	printk(VIOPATH_KERN_WARN "partition %d ended\n", remoteLp);

	viopathStatus[remoteLp].isActive = 0;

	/*
	 * For each active handler, pass them a NULL
	 * message to indicate that the other partition
	 * died
	 */
	for (i = 0; i < VIO_MAX_SUBTYPES; i++) {
		if (vio_handler[i] != NULL)
			(*vio_handler[i])(NULL);
	}
}

int vio_setHandler(int subtype, vio_event_handler_t *beh)
{
	subtype = subtype >> VIOMAJOR_SUBTYPE_SHIFT;
	if ((subtype < 0) || (subtype >= VIO_MAX_SUBTYPES))
		return -EINVAL;
	if (vio_handler[subtype] != NULL)
		return -EBUSY;
	vio_handler[subtype] = beh;
	return 0;
}
EXPORT_SYMBOL(vio_setHandler);

int vio_clearHandler(int subtype)
{
	subtype = subtype >> VIOMAJOR_SUBTYPE_SHIFT;
	if ((subtype < 0) || (subtype >= VIO_MAX_SUBTYPES))
		return -EINVAL;
	if (vio_handler[subtype] == NULL)
		return -EAGAIN;
	vio_handler[subtype] = NULL;
	return 0;
}
EXPORT_SYMBOL(vio_clearHandler);

static void handleConfig(struct HvLpEvent *event)
{
	if (!event)
		return;
345
	if (hvlpevent_is_int(event)) {
Linus Torvalds's avatar
Linus Torvalds committed
346 347 348 349
		printk(VIOPATH_KERN_WARN
		       "unexpected config request from partition %d",
		       event->xSourceLp);

350
		if (hvlpevent_need_ack(event)) {
Linus Torvalds's avatar
Linus Torvalds committed
351 352 353 354 355 356
			event->xRc = HvLpEvent_Rc_InvalidSubtype;
			HvCallEvent_ackLpEvent(event);
		}
		return;
	}

357
	complete((struct completion *)event->xCorrelationToken);
Linus Torvalds's avatar
Linus Torvalds committed
358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376
}

/*
 * Initialization of the hosting partition
 */
void vio_set_hostlp(void)
{
	/*
	 * If this has already been set then we DON'T want to either change
	 * it or re-register the proc file system
	 */
	if (viopath_hostLp != HvLpIndexInvalid)
		return;

	/*
	 * Figure out our hosting partition.  This isn't allowed to change
	 * while we're active
	 */
	viopath_ourLp = HvLpConfig_getLpIndex();
377
	viopath_hostLp = HvLpConfig_getHostingLpIndex(viopath_ourLp);
Linus Torvalds's avatar
Linus Torvalds committed
378 379 380 381 382 383

	if (viopath_hostLp != HvLpIndexInvalid)
		vio_setHandler(viomajorsubtype_config, handleConfig);
}
EXPORT_SYMBOL(vio_set_hostlp);

384
static void vio_handleEvent(struct HvLpEvent *event)
Linus Torvalds's avatar
Linus Torvalds committed
385 386 387 388 389
{
	HvLpIndex remoteLp;
	int subtype = (event->xSubtype & VIOMAJOR_SUBTYPE_MASK)
		>> VIOMAJOR_SUBTYPE_SHIFT;

390
	if (hvlpevent_is_int(event)) {
Linus Torvalds's avatar
Linus Torvalds committed
391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448
		remoteLp = event->xSourceLp;
		/*
		 * The isActive is checked because if the hosting partition
		 * went down and came back up it would not be active but it
		 * would have different source and target instances, in which
		 * case we'd want to reset them.  This case really protects
		 * against an unauthorized active partition sending interrupts
		 * or acks to this linux partition.
		 */
		if (viopathStatus[remoteLp].isActive
		    && (event->xSourceInstanceId !=
			viopathStatus[remoteLp].mTargetInst)) {
			printk(VIOPATH_KERN_WARN
			       "message from invalid partition. "
			       "int msg rcvd, source inst (%d) doesnt match (%d)\n",
			       viopathStatus[remoteLp].mTargetInst,
			       event->xSourceInstanceId);
			return;
		}

		if (viopathStatus[remoteLp].isActive
		    && (event->xTargetInstanceId !=
			viopathStatus[remoteLp].mSourceInst)) {
			printk(VIOPATH_KERN_WARN
			       "message from invalid partition. "
			       "int msg rcvd, target inst (%d) doesnt match (%d)\n",
			       viopathStatus[remoteLp].mSourceInst,
			       event->xTargetInstanceId);
			return;
		}
	} else {
		remoteLp = event->xTargetLp;
		if (event->xSourceInstanceId !=
		    viopathStatus[remoteLp].mSourceInst) {
			printk(VIOPATH_KERN_WARN
			       "message from invalid partition. "
			       "ack msg rcvd, source inst (%d) doesnt match (%d)\n",
			       viopathStatus[remoteLp].mSourceInst,
			       event->xSourceInstanceId);
			return;
		}

		if (event->xTargetInstanceId !=
		    viopathStatus[remoteLp].mTargetInst) {
			printk(VIOPATH_KERN_WARN
			       "message from invalid partition. "
			       "viopath: ack msg rcvd, target inst (%d) doesnt match (%d)\n",
			       viopathStatus[remoteLp].mTargetInst,
			       event->xTargetInstanceId);
			return;
		}
	}

	if (vio_handler[subtype] == NULL) {
		printk(VIOPATH_KERN_WARN
		       "unexpected virtual io event subtype %d from partition %d\n",
		       event->xSubtype, remoteLp);
		/* No handler.  Ack if necessary */
449
		if (hvlpevent_is_int(event) && hvlpevent_need_ack(event)) {
Linus Torvalds's avatar
Linus Torvalds committed
450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467
			event->xRc = HvLpEvent_Rc_InvalidSubtype;
			HvCallEvent_ackLpEvent(event);
		}
		return;
	}

	/* This innocuous little line is where all the real work happens */
	(*vio_handler[subtype])(event);
}

static void viopath_donealloc(void *parm, int number)
{
	struct alloc_parms *parmsp = parm;

	parmsp->number = number;
	if (parmsp->used_wait_atomic)
		atomic_set(&parmsp->wait_atomic, 0);
	else
468
		complete(&parmsp->done);
Linus Torvalds's avatar
Linus Torvalds committed
469 470 471 472 473 474 475 476 477 478 479
}

static int allocateEvents(HvLpIndex remoteLp, int numEvents)
{
	struct alloc_parms parms;

	if (system_state != SYSTEM_RUNNING) {
		parms.used_wait_atomic = 1;
		atomic_set(&parms.wait_atomic, 1);
	} else {
		parms.used_wait_atomic = 0;
480
		init_completion(&parms.done);
Linus Torvalds's avatar
Linus Torvalds committed
481 482 483 484 485 486 487
	}
	mf_allocate_lp_events(remoteLp, HvLpEvent_Type_VirtualIo, 250,	/* It would be nice to put a real number here! */
			    numEvents, &viopath_donealloc, &parms);
	if (system_state != SYSTEM_RUNNING) {
		while (atomic_read(&parms.wait_atomic))
			mb();
	} else
488
		wait_for_completion(&parms.done);
Linus Torvalds's avatar
Linus Torvalds committed
489 490 491 492 493 494 495 496 497
	return parms.number;
}

int viopath_open(HvLpIndex remoteLp, int subtype, int numReq)
{
	int i;
	unsigned long flags;
	int tempNumAllocated;

498
	if ((remoteLp >= HVMAXARCHITECTEDLPS) || (remoteLp == HvLpIndexInvalid))
Linus Torvalds's avatar
Linus Torvalds committed
499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568
		return -EINVAL;

	subtype = subtype >> VIOMAJOR_SUBTYPE_SHIFT;
	if ((subtype < 0) || (subtype >= VIO_MAX_SUBTYPES))
		return -EINVAL;

	spin_lock_irqsave(&statuslock, flags);

	if (!event_buffer_initialised) {
		for (i = 0; i < VIO_MAX_SUBTYPES; i++)
			atomic_set(&event_buffer_available[i], 1);
		event_buffer_initialised = 1;
	}

	viopathStatus[remoteLp].users[subtype]++;

	if (!viopathStatus[remoteLp].isOpen) {
		viopathStatus[remoteLp].isOpen = 1;
		HvCallEvent_openLpEventPath(remoteLp, HvLpEvent_Type_VirtualIo);

		/*
		 * Don't hold the spinlock during an operation that
		 * can sleep.
		 */
		spin_unlock_irqrestore(&statuslock, flags);
		tempNumAllocated = allocateEvents(remoteLp, 1);
		spin_lock_irqsave(&statuslock, flags);

		viopathStatus[remoteLp].numberAllocated += tempNumAllocated;

		if (viopathStatus[remoteLp].numberAllocated == 0) {
			HvCallEvent_closeLpEventPath(remoteLp,
					HvLpEvent_Type_VirtualIo);

			spin_unlock_irqrestore(&statuslock, flags);
			return -ENOMEM;
		}

		viopathStatus[remoteLp].mSourceInst =
			HvCallEvent_getSourceLpInstanceId(remoteLp,
					HvLpEvent_Type_VirtualIo);
		viopathStatus[remoteLp].mTargetInst =
			HvCallEvent_getTargetLpInstanceId(remoteLp,
					HvLpEvent_Type_VirtualIo);
		HvLpEvent_registerHandler(HvLpEvent_Type_VirtualIo,
					  &vio_handleEvent);
		sendMonMsg(remoteLp);
		printk(VIOPATH_KERN_INFO "opening connection to partition %d, "
				"setting sinst %d, tinst %d\n",
				remoteLp, viopathStatus[remoteLp].mSourceInst,
				viopathStatus[remoteLp].mTargetInst);
	}

	spin_unlock_irqrestore(&statuslock, flags);
	tempNumAllocated = allocateEvents(remoteLp, numReq);
	spin_lock_irqsave(&statuslock, flags);
	viopathStatus[remoteLp].numberAllocated += tempNumAllocated;
	spin_unlock_irqrestore(&statuslock, flags);

	return 0;
}
EXPORT_SYMBOL(viopath_open);

int viopath_close(HvLpIndex remoteLp, int subtype, int numReq)
{
	unsigned long flags;
	int i;
	int numOpen;
	struct alloc_parms parms;

569
	if ((remoteLp >= HVMAXARCHITECTEDLPS) || (remoteLp == HvLpIndexInvalid))
Linus Torvalds's avatar
Linus Torvalds committed
570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588
		return -EINVAL;

	subtype = subtype >> VIOMAJOR_SUBTYPE_SHIFT;
	if ((subtype < 0) || (subtype >= VIO_MAX_SUBTYPES))
		return -EINVAL;

	spin_lock_irqsave(&statuslock, flags);
	/*
	 * If the viopath_close somehow gets called before a
	 * viopath_open it could decrement to -1 which is a non
	 * recoverable state so we'll prevent this from
	 * happening.
	 */
	if (viopathStatus[remoteLp].users[subtype] > 0)
		viopathStatus[remoteLp].users[subtype]--;

	spin_unlock_irqrestore(&statuslock, flags);

	parms.used_wait_atomic = 0;
589
	init_completion(&parms.done);
Linus Torvalds's avatar
Linus Torvalds committed
590 591
	mf_deallocate_lp_events(remoteLp, HvLpEvent_Type_VirtualIo,
			      numReq, &viopath_donealloc, &parms);
592
	wait_for_completion(&parms.done);
Linus Torvalds's avatar
Linus Torvalds committed
593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683

	spin_lock_irqsave(&statuslock, flags);
	for (i = 0, numOpen = 0; i < VIO_MAX_SUBTYPES; i++)
		numOpen += viopathStatus[remoteLp].users[i];

	if ((viopathStatus[remoteLp].isOpen) && (numOpen == 0)) {
		printk(VIOPATH_KERN_INFO "closing connection to partition %d",
				remoteLp);

		HvCallEvent_closeLpEventPath(remoteLp,
					     HvLpEvent_Type_VirtualIo);
		viopathStatus[remoteLp].isOpen = 0;
		viopathStatus[remoteLp].isActive = 0;

		for (i = 0; i < VIO_MAX_SUBTYPES; i++)
			atomic_set(&event_buffer_available[i], 0);
		event_buffer_initialised = 0;
	}
	spin_unlock_irqrestore(&statuslock, flags);
	return 0;
}
EXPORT_SYMBOL(viopath_close);

void *vio_get_event_buffer(int subtype)
{
	subtype = subtype >> VIOMAJOR_SUBTYPE_SHIFT;
	if ((subtype < 0) || (subtype >= VIO_MAX_SUBTYPES))
		return NULL;

	if (atomic_dec_if_positive(&event_buffer_available[subtype]) == 0)
		return &event_buffer[subtype * 256];
	else
		return NULL;
}
EXPORT_SYMBOL(vio_get_event_buffer);

void vio_free_event_buffer(int subtype, void *buffer)
{
	subtype = subtype >> VIOMAJOR_SUBTYPE_SHIFT;
	if ((subtype < 0) || (subtype >= VIO_MAX_SUBTYPES)) {
		printk(VIOPATH_KERN_WARN
		       "unexpected subtype %d freeing event buffer\n", subtype);
		return;
	}

	if (atomic_read(&event_buffer_available[subtype]) != 0) {
		printk(VIOPATH_KERN_WARN
		       "freeing unallocated event buffer, subtype %d\n",
		       subtype);
		return;
	}

	if (buffer != &event_buffer[subtype * 256]) {
		printk(VIOPATH_KERN_WARN
		       "freeing invalid event buffer, subtype %d\n", subtype);
	}

	atomic_set(&event_buffer_available[subtype], 1);
}
EXPORT_SYMBOL(vio_free_event_buffer);

static const struct vio_error_entry vio_no_error =
    { 0, 0, "Non-VIO Error" };
static const struct vio_error_entry vio_unknown_error =
    { 0, EIO, "Unknown Error" };

static const struct vio_error_entry vio_default_errors[] = {
	{0x0001, EIO, "No Connection"},
	{0x0002, EIO, "No Receiver"},
	{0x0003, EIO, "No Buffer Available"},
	{0x0004, EBADRQC, "Invalid Message Type"},
	{0x0000, 0, NULL},
};

const struct vio_error_entry *vio_lookup_rc(
		const struct vio_error_entry *local_table, u16 rc)
{
	const struct vio_error_entry *cur;

	if (!rc)
		return &vio_no_error;
	if (local_table)
		for (cur = local_table; cur->rc; ++cur)
			if (cur->rc == rc)
				return cur;
	for (cur = vio_default_errors; cur->rc; ++cur)
		if (cur->rc == rc)
			return cur;
	return &vio_unknown_error;
}
EXPORT_SYMBOL(vio_lookup_rc);