xref: /titanic_41/usr/src/uts/common/xen/io/xdf.c (revision 24fe0b3bf671e123467ce1df0b67cadd3614c8e4)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 /*
28  * xdf.c - Xen Virtual Block Device Driver
29  * TODO:
30  *	- support alternate block size (currently only DEV_BSIZE supported)
31  *	- revalidate geometry for removable devices
32  *
33  * This driver export solaris disk device nodes, accepts IO requests from
34  * those nodes, and services those requests by talking to a backend device
35  * in another domain.
36  *
37  * Communication with the backend device is done via a ringbuffer (which is
38  * managed via xvdi interfaces) and dma memory (which is managed via ddi
39  * interfaces).
40  *
41  * Communication with the backend device is dependant upon establishing a
42  * connection to the backend device.  This connection process involves
43  * reading device configuration information from xenbus and publishing
44  * some frontend runtime configuration parameters via the xenbus (for
45  * consumption by the backend).  Once we've published runtime configuration
46  * information via the xenbus, the backend device can enter the connected
47  * state and we'll enter the XD_CONNECTED state.  But before we can allow
48  * random IO to begin, we need to do IO to the backend device to determine
49  * the device label and if flush operations are supported.  Once this is
50  * done we enter the XD_READY state and can process any IO operations.
51  *
52  * We recieve notifications of xenbus state changes for the backend device
53  * (aka, the "other end") via the xdf_oe_change() callback.  This callback
54  * is single threaded, meaning that we can't recieve new notification of
55  * other end state changes while we're processing an outstanding
56  * notification of an other end state change.  There for we can't do any
57  * blocking operations from the xdf_oe_change() callback.  This is why we
58  * have a seperate taskq (xdf_ready_tq) which exists to do the necessary
59  * IO to get us from the XD_CONNECTED to the XD_READY state.  All IO
60  * generated by the xdf_ready_tq thread (xdf_ready_tq_thread) will go
61  * throught xdf_lb_rdwr(), which is a synchronous IO interface.  IOs
62  * generated by the xdf_ready_tq_thread thread have priority over all
63  * other IO requests.
64  *
65  * We also communicate with the backend device via the xenbus "media-req"
66  * (XBP_MEDIA_REQ) property.  For more information on this see the
67  * comments in blkif.h.
68  */
69 
70 #include <io/xdf.h>
71 
72 #include <sys/conf.h>
73 #include <sys/dkio.h>
74 #include <sys/promif.h>
75 #include <sys/sysmacros.h>
76 #include <sys/kstat.h>
77 #include <sys/mach_mmu.h>
78 #ifdef XPV_HVM_DRIVER
79 #include <sys/xpv_support.h>
80 #include <sys/sunndi.h>
81 #else /* !XPV_HVM_DRIVER */
82 #include <sys/evtchn_impl.h>
83 #endif /* !XPV_HVM_DRIVER */
84 #include <public/io/xenbus.h>
85 #include <xen/sys/xenbus_impl.h>
86 #include <sys/scsi/generic/inquiry.h>
87 #include <xen/io/blkif_impl.h>
88 #include <sys/fdio.h>
89 #include <sys/cdio.h>
90 
91 /*
92  * DEBUG_EVAL can be used to include debug only statements without
93  * having to use '#ifdef DEBUG' statements
94  */
95 #ifdef DEBUG
96 #define	DEBUG_EVAL(x)	(x)
97 #else /* !DEBUG */
98 #define	DEBUG_EVAL(x)
99 #endif /* !DEBUG */
100 
101 #define	XDF_DRAIN_MSEC_DELAY		(50*1000)	/* 00.05 sec */
102 #define	XDF_DRAIN_RETRY_COUNT		200		/* 10.00 sec */
103 
104 #define	INVALID_DOMID	((domid_t)-1)
105 #define	FLUSH_DISKCACHE	0x1
106 #define	WRITE_BARRIER	0x2
107 #define	DEFAULT_FLUSH_BLOCK	156 /* block to write to cause a cache flush */
108 #define	USE_WRITE_BARRIER(vdp)						\
109 	((vdp)->xdf_feature_barrier && !(vdp)->xdf_flush_supported)
110 #define	USE_FLUSH_DISKCACHE(vdp)					\
111 	((vdp)->xdf_feature_barrier && (vdp)->xdf_flush_supported)
112 #define	IS_WRITE_BARRIER(vdp, bp)					\
113 	(!IS_READ(bp) && USE_WRITE_BARRIER(vdp) &&			\
114 	((bp)->b_un.b_addr == (vdp)->xdf_cache_flush_block))
115 #define	IS_FLUSH_DISKCACHE(bp)						\
116 	(!IS_READ(bp) && USE_FLUSH_DISKCACHE(vdp) && ((bp)->b_bcount == 0))
117 
118 #define	VREQ_DONE(vreq)							\
119 	VOID2BOOLEAN(((vreq)->v_status == VREQ_DMAWIN_DONE) &&		\
120 	    (((vreq)->v_flush_diskcache == FLUSH_DISKCACHE) ||		\
121 	    (((vreq)->v_dmaw + 1) == (vreq)->v_ndmaws)))
122 
123 #define	BP_VREQ(bp)		((v_req_t *)((bp)->av_back))
124 #define	BP_VREQ_SET(bp, vreq)	(((bp)->av_back = (buf_t *)(vreq)))
125 
126 extern int		do_polled_io;
127 
128 /* run-time tunables that we don't want the compiler to optimize away */
129 volatile int		xdf_debug = 0;
130 volatile boolean_t	xdf_barrier_flush_disable = B_FALSE;
131 
132 /* per module globals */
133 major_t			xdf_major;
134 static void		*xdf_ssp;
135 static kmem_cache_t	*xdf_vreq_cache;
136 static kmem_cache_t	*xdf_gs_cache;
137 static int		xdf_maxphys = XB_MAXPHYS;
138 static diskaddr_t	xdf_flush_block = DEFAULT_FLUSH_BLOCK;
139 static int		xdf_fbrewrites;	/* flush block re-write count */
140 
141 /* misc public functions (used by xdf_shell.c) */
142 int xdf_lb_rdwr(dev_info_t *, uchar_t, void *, diskaddr_t, size_t, void *);
143 int xdf_lb_getinfo(dev_info_t *, int, void *, void *);
144 
145 /*  misc private functions */
146 static void xdf_io_start(xdf_t *);
147 
148 /* callbacks from commmon label */
149 static cmlb_tg_ops_t xdf_lb_ops = {
150 	TG_DK_OPS_VERSION_1,
151 	xdf_lb_rdwr,
152 	xdf_lb_getinfo
153 };
154 
155 /*
156  * I/O buffer DMA attributes
157  * Make sure: one DMA window contains BLKIF_MAX_SEGMENTS_PER_REQUEST at most
158  */
159 static ddi_dma_attr_t xb_dma_attr = {
160 	DMA_ATTR_V0,
161 	(uint64_t)0,			/* lowest address */
162 	(uint64_t)0xffffffffffffffff,	/* highest usable address */
163 	(uint64_t)0xffffff,		/* DMA counter limit max */
164 	(uint64_t)XB_BSIZE,		/* alignment in bytes */
165 	XB_BSIZE - 1,			/* bitmap of burst sizes */
166 	XB_BSIZE,			/* min transfer */
167 	(uint64_t)XB_MAX_XFER, 		/* maximum transfer */
168 	(uint64_t)PAGEOFFSET,		/* 1 page segment length  */
169 	BLKIF_MAX_SEGMENTS_PER_REQUEST,	/* maximum number of segments */
170 	XB_BSIZE,			/* granularity */
171 	0,				/* flags (reserved) */
172 };
173 
174 static ddi_device_acc_attr_t xc_acc_attr = {
175 	DDI_DEVICE_ATTR_V0,
176 	DDI_NEVERSWAP_ACC,
177 	DDI_STRICTORDER_ACC
178 };
179 
180 static void
181 xdf_timeout_handler(void *arg)
182 {
183 	xdf_t *vdp = arg;
184 
185 	mutex_enter(&vdp->xdf_dev_lk);
186 	vdp->xdf_timeout_id = 0;
187 	mutex_exit(&vdp->xdf_dev_lk);
188 
189 	/* new timeout thread could be re-scheduled */
190 	xdf_io_start(vdp);
191 }
192 
193 /*
194  * callback func when DMA/GTE resources is available
195  *
196  * Note: we only register one callback function to grant table subsystem
197  * since we only have one 'struct gnttab_free_callback' in xdf_t.
198  */
199 static int
200 xdf_dmacallback(caddr_t arg)
201 {
202 	xdf_t *vdp = (xdf_t *)arg;
203 	ASSERT(vdp != NULL);
204 
205 	DPRINTF(DMA_DBG, ("xdf@%s: DMA callback started\n",
206 	    vdp->xdf_addr));
207 
208 	ddi_trigger_softintr(vdp->xdf_softintr_id);
209 	return (DDI_DMA_CALLBACK_DONE);
210 }
211 
212 static ge_slot_t *
213 gs_get(xdf_t *vdp, int isread)
214 {
215 	grant_ref_t gh;
216 	ge_slot_t *gs;
217 
218 	/* try to alloc GTEs needed in this slot, first */
219 	if (gnttab_alloc_grant_references(
220 	    BLKIF_MAX_SEGMENTS_PER_REQUEST, &gh) == -1) {
221 		if (vdp->xdf_gnt_callback.next == NULL) {
222 			SETDMACBON(vdp);
223 			gnttab_request_free_callback(
224 			    &vdp->xdf_gnt_callback,
225 			    (void (*)(void *))xdf_dmacallback,
226 			    (void *)vdp,
227 			    BLKIF_MAX_SEGMENTS_PER_REQUEST);
228 		}
229 		return (NULL);
230 	}
231 
232 	gs = kmem_cache_alloc(xdf_gs_cache, KM_NOSLEEP);
233 	if (gs == NULL) {
234 		gnttab_free_grant_references(gh);
235 		if (vdp->xdf_timeout_id == 0)
236 			/* restart I/O after one second */
237 			vdp->xdf_timeout_id =
238 			    timeout(xdf_timeout_handler, vdp, hz);
239 		return (NULL);
240 	}
241 
242 	/* init gs_slot */
243 	gs->gs_oeid = vdp->xdf_peer;
244 	gs->gs_isread = isread;
245 	gs->gs_ghead = gh;
246 	gs->gs_ngrefs = 0;
247 
248 	return (gs);
249 }
250 
251 static void
252 gs_free(ge_slot_t *gs)
253 {
254 	int		i;
255 
256 	/* release all grant table entry resources used in this slot */
257 	for (i = 0; i < gs->gs_ngrefs; i++)
258 		gnttab_end_foreign_access(gs->gs_ge[i], !gs->gs_isread, 0);
259 	gnttab_free_grant_references(gs->gs_ghead);
260 	list_remove(&gs->gs_vreq->v_gs, gs);
261 	kmem_cache_free(xdf_gs_cache, gs);
262 }
263 
264 static grant_ref_t
265 gs_grant(ge_slot_t *gs, mfn_t mfn)
266 {
267 	grant_ref_t gr = gnttab_claim_grant_reference(&gs->gs_ghead);
268 
269 	ASSERT(gr != -1);
270 	ASSERT(gs->gs_ngrefs < BLKIF_MAX_SEGMENTS_PER_REQUEST);
271 	gs->gs_ge[gs->gs_ngrefs++] = gr;
272 	gnttab_grant_foreign_access_ref(gr, gs->gs_oeid, mfn, !gs->gs_isread);
273 
274 	return (gr);
275 }
276 
277 /*
278  * Alloc a vreq for this bp
279  * bp->av_back contains the pointer to the vreq upon return
280  */
281 static v_req_t *
282 vreq_get(xdf_t *vdp, buf_t *bp)
283 {
284 	v_req_t *vreq = NULL;
285 
286 	ASSERT(BP_VREQ(bp) == NULL);
287 
288 	vreq = kmem_cache_alloc(xdf_vreq_cache, KM_NOSLEEP);
289 	if (vreq == NULL) {
290 		if (vdp->xdf_timeout_id == 0)
291 			/* restart I/O after one second */
292 			vdp->xdf_timeout_id =
293 			    timeout(xdf_timeout_handler, vdp, hz);
294 		return (NULL);
295 	}
296 	bzero(vreq, sizeof (v_req_t));
297 	list_create(&vreq->v_gs, sizeof (ge_slot_t),
298 	    offsetof(ge_slot_t, gs_vreq_link));
299 	vreq->v_buf = bp;
300 	vreq->v_status = VREQ_INIT;
301 	vreq->v_runq = B_FALSE;
302 	BP_VREQ_SET(bp, vreq);
303 	/* init of other fields in vreq is up to the caller */
304 
305 	list_insert_head(&vdp->xdf_vreq_act, (void *)vreq);
306 
307 	return (vreq);
308 }
309 
310 static void
311 vreq_free(xdf_t *vdp, v_req_t *vreq)
312 {
313 	buf_t	*bp = vreq->v_buf;
314 
315 	ASSERT(MUTEX_HELD(&vdp->xdf_dev_lk));
316 	ASSERT(BP_VREQ(bp) == vreq);
317 
318 	list_remove(&vdp->xdf_vreq_act, vreq);
319 
320 	if (vreq->v_flush_diskcache == FLUSH_DISKCACHE)
321 		goto done;
322 
323 	switch (vreq->v_status) {
324 	case VREQ_DMAWIN_DONE:
325 	case VREQ_GS_ALLOCED:
326 	case VREQ_DMABUF_BOUND:
327 		(void) ddi_dma_unbind_handle(vreq->v_dmahdl);
328 		/*FALLTHRU*/
329 	case VREQ_DMAMEM_ALLOCED:
330 		if (!ALIGNED_XFER(bp)) {
331 			ASSERT(vreq->v_abuf != NULL);
332 			if (!IS_ERROR(bp) && IS_READ(bp))
333 				bcopy(vreq->v_abuf, bp->b_un.b_addr,
334 				    bp->b_bcount);
335 			ddi_dma_mem_free(&vreq->v_align);
336 		}
337 		/*FALLTHRU*/
338 	case VREQ_MEMDMAHDL_ALLOCED:
339 		if (!ALIGNED_XFER(bp))
340 			ddi_dma_free_handle(&vreq->v_memdmahdl);
341 		/*FALLTHRU*/
342 	case VREQ_DMAHDL_ALLOCED:
343 		ddi_dma_free_handle(&vreq->v_dmahdl);
344 		break;
345 	default:
346 		break;
347 	}
348 done:
349 	ASSERT(!vreq->v_runq);
350 	list_destroy(&vreq->v_gs);
351 	kmem_cache_free(xdf_vreq_cache, vreq);
352 }
353 
354 /*
355  * Snarf new data if our flush block was re-written
356  */
357 static void
358 check_fbwrite(xdf_t *vdp, buf_t *bp, daddr_t blkno)
359 {
360 	int nblks;
361 	boolean_t mapin;
362 
363 	if (IS_WRITE_BARRIER(vdp, bp))
364 		return; /* write was a flush write */
365 
366 	mapin = B_FALSE;
367 	nblks = bp->b_bcount >> DEV_BSHIFT;
368 	if (xdf_flush_block >= blkno && xdf_flush_block < (blkno + nblks)) {
369 		xdf_fbrewrites++;
370 		if (bp->b_flags & (B_PAGEIO | B_PHYS)) {
371 			mapin = B_TRUE;
372 			bp_mapin(bp);
373 		}
374 		bcopy(bp->b_un.b_addr +
375 		    ((xdf_flush_block - blkno) << DEV_BSHIFT),
376 		    vdp->xdf_cache_flush_block, DEV_BSIZE);
377 		if (mapin)
378 			bp_mapout(bp);
379 	}
380 }
381 
382 /*
383  * Initalize the DMA and grant table resources for the buf
384  */
385 static int
386 vreq_setup(xdf_t *vdp, v_req_t *vreq)
387 {
388 	int rc;
389 	ddi_dma_attr_t dmaattr;
390 	uint_t ndcs, ndws;
391 	ddi_dma_handle_t dh;
392 	ddi_dma_handle_t mdh;
393 	ddi_dma_cookie_t dc;
394 	ddi_acc_handle_t abh;
395 	caddr_t	aba;
396 	ge_slot_t *gs;
397 	size_t bufsz;
398 	off_t off;
399 	size_t sz;
400 	buf_t *bp = vreq->v_buf;
401 	int dma_flags = (IS_READ(bp) ? DDI_DMA_READ : DDI_DMA_WRITE) |
402 	    DDI_DMA_STREAMING | DDI_DMA_PARTIAL;
403 
404 	switch (vreq->v_status) {
405 	case VREQ_INIT:
406 		if (IS_FLUSH_DISKCACHE(bp)) {
407 			if ((gs = gs_get(vdp, IS_READ(bp))) == NULL) {
408 				DPRINTF(DMA_DBG, ("xdf@%s: "
409 				    "get ge_slotfailed\n", vdp->xdf_addr));
410 				return (DDI_FAILURE);
411 			}
412 			vreq->v_blkno = 0;
413 			vreq->v_nslots = 1;
414 			vreq->v_flush_diskcache = FLUSH_DISKCACHE;
415 			vreq->v_status = VREQ_GS_ALLOCED;
416 			gs->gs_vreq = vreq;
417 			list_insert_head(&vreq->v_gs, gs);
418 			return (DDI_SUCCESS);
419 		}
420 
421 		if (IS_WRITE_BARRIER(vdp, bp))
422 			vreq->v_flush_diskcache = WRITE_BARRIER;
423 		vreq->v_blkno = bp->b_blkno +
424 		    (diskaddr_t)(uintptr_t)bp->b_private;
425 		/* See if we wrote new data to our flush block */
426 		if (!IS_READ(bp) && USE_WRITE_BARRIER(vdp))
427 			check_fbwrite(vdp, bp, vreq->v_blkno);
428 		vreq->v_status = VREQ_INIT_DONE;
429 		/*FALLTHRU*/
430 
431 	case VREQ_INIT_DONE:
432 		/*
433 		 * alloc DMA handle
434 		 */
435 		rc = ddi_dma_alloc_handle(vdp->xdf_dip, &xb_dma_attr,
436 		    xdf_dmacallback, (caddr_t)vdp, &dh);
437 		if (rc != DDI_SUCCESS) {
438 			SETDMACBON(vdp);
439 			DPRINTF(DMA_DBG, ("xdf@%s: DMA handle alloc failed\n",
440 			    vdp->xdf_addr));
441 			return (DDI_FAILURE);
442 		}
443 
444 		vreq->v_dmahdl = dh;
445 		vreq->v_status = VREQ_DMAHDL_ALLOCED;
446 		/*FALLTHRU*/
447 
448 	case VREQ_DMAHDL_ALLOCED:
449 		/*
450 		 * alloc dma handle for 512-byte aligned buf
451 		 */
452 		if (!ALIGNED_XFER(bp)) {
453 			/*
454 			 * XXPV: we need to temporarily enlarge the seg
455 			 * boundary and s/g length to work round CR6381968
456 			 */
457 			dmaattr = xb_dma_attr;
458 			dmaattr.dma_attr_seg = (uint64_t)-1;
459 			dmaattr.dma_attr_sgllen = INT_MAX;
460 			rc = ddi_dma_alloc_handle(vdp->xdf_dip, &dmaattr,
461 			    xdf_dmacallback, (caddr_t)vdp, &mdh);
462 			if (rc != DDI_SUCCESS) {
463 				SETDMACBON(vdp);
464 				DPRINTF(DMA_DBG, ("xdf@%s: "
465 				    "unaligned buf DMAhandle alloc failed\n",
466 				    vdp->xdf_addr));
467 				return (DDI_FAILURE);
468 			}
469 			vreq->v_memdmahdl = mdh;
470 			vreq->v_status = VREQ_MEMDMAHDL_ALLOCED;
471 		}
472 		/*FALLTHRU*/
473 
474 	case VREQ_MEMDMAHDL_ALLOCED:
475 		/*
476 		 * alloc 512-byte aligned buf
477 		 */
478 		if (!ALIGNED_XFER(bp)) {
479 			if (bp->b_flags & (B_PAGEIO | B_PHYS))
480 				bp_mapin(bp);
481 			rc = ddi_dma_mem_alloc(vreq->v_memdmahdl,
482 			    roundup(bp->b_bcount, XB_BSIZE), &xc_acc_attr,
483 			    DDI_DMA_STREAMING, xdf_dmacallback, (caddr_t)vdp,
484 			    &aba, &bufsz, &abh);
485 			if (rc != DDI_SUCCESS) {
486 				SETDMACBON(vdp);
487 				DPRINTF(DMA_DBG, ("xdf@%s: "
488 				    "DMA mem allocation failed\n",
489 				    vdp->xdf_addr));
490 				return (DDI_FAILURE);
491 			}
492 
493 			vreq->v_abuf = aba;
494 			vreq->v_align = abh;
495 			vreq->v_status = VREQ_DMAMEM_ALLOCED;
496 
497 			ASSERT(bufsz >= bp->b_bcount);
498 			if (!IS_READ(bp))
499 				bcopy(bp->b_un.b_addr, vreq->v_abuf,
500 				    bp->b_bcount);
501 		}
502 		/*FALLTHRU*/
503 
504 	case VREQ_DMAMEM_ALLOCED:
505 		/*
506 		 * dma bind
507 		 */
508 		if (ALIGNED_XFER(bp)) {
509 			rc = ddi_dma_buf_bind_handle(vreq->v_dmahdl, bp,
510 			    dma_flags, xdf_dmacallback, (caddr_t)vdp,
511 			    &dc, &ndcs);
512 		} else {
513 			rc = ddi_dma_addr_bind_handle(vreq->v_dmahdl,
514 			    NULL, vreq->v_abuf, bp->b_bcount, dma_flags,
515 			    xdf_dmacallback, (caddr_t)vdp, &dc, &ndcs);
516 		}
517 		if (rc == DDI_DMA_MAPPED || rc == DDI_DMA_PARTIAL_MAP) {
518 			/* get num of dma windows */
519 			if (rc == DDI_DMA_PARTIAL_MAP) {
520 				rc = ddi_dma_numwin(vreq->v_dmahdl, &ndws);
521 				ASSERT(rc == DDI_SUCCESS);
522 			} else {
523 				ndws = 1;
524 			}
525 		} else {
526 			SETDMACBON(vdp);
527 			DPRINTF(DMA_DBG, ("xdf@%s: DMA bind failed\n",
528 			    vdp->xdf_addr));
529 			return (DDI_FAILURE);
530 		}
531 
532 		vreq->v_dmac = dc;
533 		vreq->v_dmaw = 0;
534 		vreq->v_ndmacs = ndcs;
535 		vreq->v_ndmaws = ndws;
536 		vreq->v_nslots = ndws;
537 		vreq->v_status = VREQ_DMABUF_BOUND;
538 		/*FALLTHRU*/
539 
540 	case VREQ_DMABUF_BOUND:
541 		/*
542 		 * get ge_slot, callback is set upon failure from gs_get(),
543 		 * if not set previously
544 		 */
545 		if ((gs = gs_get(vdp, IS_READ(bp))) == NULL) {
546 			DPRINTF(DMA_DBG, ("xdf@%s: get ge_slot failed\n",
547 			    vdp->xdf_addr));
548 			return (DDI_FAILURE);
549 		}
550 
551 		vreq->v_status = VREQ_GS_ALLOCED;
552 		gs->gs_vreq = vreq;
553 		list_insert_head(&vreq->v_gs, gs);
554 		break;
555 
556 	case VREQ_GS_ALLOCED:
557 		/* nothing need to be done */
558 		break;
559 
560 	case VREQ_DMAWIN_DONE:
561 		/*
562 		 * move to the next dma window
563 		 */
564 		ASSERT((vreq->v_dmaw + 1) < vreq->v_ndmaws);
565 
566 		/* get a ge_slot for this DMA window */
567 		if ((gs = gs_get(vdp, IS_READ(bp))) == NULL) {
568 			DPRINTF(DMA_DBG, ("xdf@%s: get ge_slot failed\n",
569 			    vdp->xdf_addr));
570 			return (DDI_FAILURE);
571 		}
572 
573 		vreq->v_dmaw++;
574 		VERIFY(ddi_dma_getwin(vreq->v_dmahdl, vreq->v_dmaw, &off, &sz,
575 		    &vreq->v_dmac, &vreq->v_ndmacs) == DDI_SUCCESS);
576 		vreq->v_status = VREQ_GS_ALLOCED;
577 		gs->gs_vreq = vreq;
578 		list_insert_head(&vreq->v_gs, gs);
579 		break;
580 
581 	default:
582 		return (DDI_FAILURE);
583 	}
584 
585 	return (DDI_SUCCESS);
586 }
587 
588 static int
589 xdf_cmlb_attach(xdf_t *vdp)
590 {
591 	dev_info_t	*dip = vdp->xdf_dip;
592 
593 	return (cmlb_attach(dip, &xdf_lb_ops,
594 	    XD_IS_CD(vdp) ? DTYPE_RODIRECT : DTYPE_DIRECT,
595 	    XD_IS_RM(vdp),
596 	    B_TRUE,
597 	    XD_IS_CD(vdp) ? DDI_NT_CD_XVMD : DDI_NT_BLOCK_XVMD,
598 #if defined(XPV_HVM_DRIVER)
599 	    (XD_IS_CD(vdp) ? 0 : CMLB_CREATE_ALTSLICE_VTOC_16_DTYPE_DIRECT) |
600 	    CMLB_INTERNAL_MINOR_NODES,
601 #else /* !XPV_HVM_DRIVER */
602 	    XD_IS_CD(vdp) ? 0 : CMLB_FAKE_LABEL_ONE_PARTITION,
603 #endif /* !XPV_HVM_DRIVER */
604 	    vdp->xdf_vd_lbl, NULL));
605 }
606 
607 static void
608 xdf_io_err(buf_t *bp, int err, size_t resid)
609 {
610 	bioerror(bp, err);
611 	if (resid == 0)
612 		bp->b_resid = bp->b_bcount;
613 	biodone(bp);
614 }
615 
616 static void
617 xdf_kstat_enter(xdf_t *vdp, buf_t *bp)
618 {
619 	v_req_t *vreq = BP_VREQ(bp);
620 
621 	ASSERT(MUTEX_HELD(&vdp->xdf_dev_lk));
622 
623 	if (vdp->xdf_xdev_iostat == NULL)
624 		return;
625 	if ((vreq != NULL) && vreq->v_runq) {
626 		kstat_runq_enter(KSTAT_IO_PTR(vdp->xdf_xdev_iostat));
627 	} else {
628 		kstat_waitq_enter(KSTAT_IO_PTR(vdp->xdf_xdev_iostat));
629 	}
630 }
631 
632 static void
633 xdf_kstat_exit(xdf_t *vdp, buf_t *bp)
634 {
635 	v_req_t *vreq = BP_VREQ(bp);
636 
637 	ASSERT(MUTEX_HELD(&vdp->xdf_dev_lk));
638 
639 	if (vdp->xdf_xdev_iostat == NULL)
640 		return;
641 	if ((vreq != NULL) && vreq->v_runq) {
642 		kstat_runq_exit(KSTAT_IO_PTR(vdp->xdf_xdev_iostat));
643 	} else {
644 		kstat_waitq_exit(KSTAT_IO_PTR(vdp->xdf_xdev_iostat));
645 	}
646 }
647 
648 static void
649 xdf_kstat_waitq_to_runq(xdf_t *vdp, buf_t *bp)
650 {
651 	v_req_t *vreq = BP_VREQ(bp);
652 
653 	ASSERT(MUTEX_HELD(&vdp->xdf_dev_lk));
654 	ASSERT(!vreq->v_runq);
655 
656 	vreq->v_runq = B_TRUE;
657 	if (vdp->xdf_xdev_iostat == NULL)
658 		return;
659 	kstat_waitq_to_runq(KSTAT_IO_PTR(vdp->xdf_xdev_iostat));
660 }
661 
662 static void
663 xdf_kstat_runq_to_waitq(xdf_t *vdp, buf_t *bp)
664 {
665 	v_req_t *vreq = BP_VREQ(bp);
666 
667 	ASSERT(MUTEX_HELD(&vdp->xdf_dev_lk));
668 	ASSERT(vreq->v_runq);
669 
670 	vreq->v_runq = B_FALSE;
671 	if (vdp->xdf_xdev_iostat == NULL)
672 		return;
673 	kstat_runq_back_to_waitq(KSTAT_IO_PTR(vdp->xdf_xdev_iostat));
674 }
675 
676 int
677 xdf_kstat_create(dev_info_t *dip, char *ks_module, int instance)
678 {
679 	xdf_t		*vdp = (xdf_t *)ddi_get_driver_private(dip);
680 	kstat_t		*kstat;
681 	buf_t		*bp;
682 
683 	if ((kstat = kstat_create(
684 	    ks_module, instance, NULL, "disk",
685 	    KSTAT_TYPE_IO, 1, KSTAT_FLAG_PERSISTENT)) == NULL)
686 		return (-1);
687 
688 	/* See comment about locking in xdf_kstat_delete(). */
689 	mutex_enter(&vdp->xdf_iostat_lk);
690 	mutex_enter(&vdp->xdf_dev_lk);
691 
692 	/* only one kstat can exist at a time */
693 	if (vdp->xdf_xdev_iostat != NULL) {
694 		mutex_exit(&vdp->xdf_dev_lk);
695 		mutex_exit(&vdp->xdf_iostat_lk);
696 		kstat_delete(kstat);
697 		return (-1);
698 	}
699 
700 	vdp->xdf_xdev_iostat = kstat;
701 	vdp->xdf_xdev_iostat->ks_lock = &vdp->xdf_dev_lk;
702 	kstat_install(vdp->xdf_xdev_iostat);
703 
704 	/*
705 	 * Now that we've created a kstat, we need to update the waitq and
706 	 * runq counts for the kstat to reflect our current state.
707 	 *
708 	 * For a buf_t structure to be on the runq, it must have a ring
709 	 * buffer slot associated with it.  To get a ring buffer slot the
710 	 * buf must first have a v_req_t and a ge_slot_t associated with it.
711 	 * Then when it is granted a ring buffer slot, v_runq will be set to
712 	 * true.
713 	 *
714 	 * For a buf_t structure to be on the waitq, it must not be on the
715 	 * runq.  So to find all the buf_t's that should be on waitq, we
716 	 * walk the active buf list and add any buf_t's which aren't on the
717 	 * runq to the waitq.
718 	 */
719 	bp = vdp->xdf_f_act;
720 	while (bp != NULL) {
721 		xdf_kstat_enter(vdp, bp);
722 		bp = bp->av_forw;
723 	}
724 	if (vdp->xdf_ready_tq_bp != NULL)
725 		xdf_kstat_enter(vdp, vdp->xdf_ready_tq_bp);
726 
727 	mutex_exit(&vdp->xdf_dev_lk);
728 	mutex_exit(&vdp->xdf_iostat_lk);
729 	return (0);
730 }
731 
732 void
733 xdf_kstat_delete(dev_info_t *dip)
734 {
735 	xdf_t		*vdp = (xdf_t *)ddi_get_driver_private(dip);
736 	kstat_t		*kstat;
737 	buf_t		*bp;
738 
739 	/*
740 	 * The locking order here is xdf_iostat_lk and then xdf_dev_lk.
741 	 * xdf_dev_lk is used to protect the xdf_xdev_iostat pointer
742 	 * and the contents of the our kstat.  xdf_iostat_lk is used
743 	 * to protect the allocation and freeing of the actual kstat.
744 	 * xdf_dev_lk can't be used for this purpose because kstat
745 	 * readers use it to access the contents of the kstat and
746 	 * hence it can't be held when calling kstat_delete().
747 	 */
748 	mutex_enter(&vdp->xdf_iostat_lk);
749 	mutex_enter(&vdp->xdf_dev_lk);
750 
751 	if (vdp->xdf_xdev_iostat == NULL) {
752 		mutex_exit(&vdp->xdf_dev_lk);
753 		mutex_exit(&vdp->xdf_iostat_lk);
754 		return;
755 	}
756 
757 	/*
758 	 * We're about to destroy the kstat structures, so it isn't really
759 	 * necessary to update the runq and waitq counts.  But, since this
760 	 * isn't a hot code path we can afford to be a little pedantic and
761 	 * go ahead and decrement the runq and waitq kstat counters to zero
762 	 * before free'ing them.  This helps us ensure that we've gotten all
763 	 * our accounting correct.
764 	 *
765 	 * For an explanation of how we determine which buffers go on the
766 	 * runq vs which go on the waitq, see the comments in
767 	 * xdf_kstat_create().
768 	 */
769 	bp = vdp->xdf_f_act;
770 	while (bp != NULL) {
771 		xdf_kstat_exit(vdp, bp);
772 		bp = bp->av_forw;
773 	}
774 	if (vdp->xdf_ready_tq_bp != NULL)
775 		xdf_kstat_exit(vdp, vdp->xdf_ready_tq_bp);
776 
777 	kstat = vdp->xdf_xdev_iostat;
778 	vdp->xdf_xdev_iostat = NULL;
779 	mutex_exit(&vdp->xdf_dev_lk);
780 	kstat_delete(kstat);
781 	mutex_exit(&vdp->xdf_iostat_lk);
782 }
783 
784 /*
785  * Add an IO requests onto the active queue.
786  *
787  * We have to detect IOs generated by xdf_ready_tq_thread.  These IOs
788  * are used to establish a connection to the backend, so they recieve
789  * priority over all other IOs.  Since xdf_ready_tq_thread only does
790  * synchronous IO, there can only be one xdf_ready_tq_thread request at any
791  * given time and we record the buf associated with that request in
792  * xdf_ready_tq_bp.
793  */
794 static void
795 xdf_bp_push(xdf_t *vdp, buf_t *bp)
796 {
797 	ASSERT(MUTEX_HELD(&vdp->xdf_dev_lk));
798 	ASSERT(bp->av_forw == NULL);
799 
800 	xdf_kstat_enter(vdp, bp);
801 
802 	if (curthread == vdp->xdf_ready_tq_thread) {
803 		/* new IO requests from the ready thread */
804 		ASSERT(vdp->xdf_ready_tq_bp == NULL);
805 		vdp->xdf_ready_tq_bp = bp;
806 		return;
807 	}
808 
809 	/* this is normal IO request */
810 	ASSERT(bp != vdp->xdf_ready_tq_bp);
811 
812 	if (vdp->xdf_f_act == NULL) {
813 		/* this is only only IO on the active queue */
814 		ASSERT(vdp->xdf_l_act == NULL);
815 		ASSERT(vdp->xdf_i_act == NULL);
816 		vdp->xdf_f_act = vdp->xdf_l_act = vdp->xdf_i_act = bp;
817 		return;
818 	}
819 
820 	/* add this IO to the tail of the active queue */
821 	vdp->xdf_l_act->av_forw = bp;
822 	vdp->xdf_l_act = bp;
823 	if (vdp->xdf_i_act == NULL)
824 		vdp->xdf_i_act = bp;
825 }
826 
827 static void
828 xdf_bp_pop(xdf_t *vdp, buf_t *bp)
829 {
830 	buf_t	*bp_iter;
831 
832 	ASSERT(MUTEX_HELD(&vdp->xdf_dev_lk));
833 	ASSERT(VREQ_DONE(BP_VREQ(bp)));
834 
835 	if (vdp->xdf_ready_tq_bp == bp) {
836 		/* we're done with a ready thread IO request */
837 		ASSERT(bp->av_forw == NULL);
838 		vdp->xdf_ready_tq_bp = NULL;
839 		return;
840 	}
841 
842 	/* we're done with a normal IO request */
843 	ASSERT((bp->av_forw != NULL) || (bp == vdp->xdf_l_act));
844 	ASSERT((bp->av_forw == NULL) || (bp != vdp->xdf_l_act));
845 	ASSERT(VREQ_DONE(BP_VREQ(vdp->xdf_f_act)));
846 	ASSERT(vdp->xdf_f_act != vdp->xdf_i_act);
847 
848 	if (bp == vdp->xdf_f_act) {
849 		/* This IO was at the head of our active queue. */
850 		vdp->xdf_f_act = bp->av_forw;
851 		if (bp == vdp->xdf_l_act)
852 			vdp->xdf_l_act = NULL;
853 	} else {
854 		/* There IO finished before some other pending IOs. */
855 		bp_iter = vdp->xdf_f_act;
856 		while (bp != bp_iter->av_forw) {
857 			bp_iter = bp_iter->av_forw;
858 			ASSERT(VREQ_DONE(BP_VREQ(bp_iter)));
859 			ASSERT(bp_iter != vdp->xdf_i_act);
860 		}
861 		bp_iter->av_forw = bp->av_forw;
862 		if (bp == vdp->xdf_l_act)
863 			vdp->xdf_l_act = bp_iter;
864 	}
865 	bp->av_forw = NULL;
866 }
867 
868 static buf_t *
869 xdf_bp_next(xdf_t *vdp)
870 {
871 	v_req_t	*vreq;
872 	buf_t	*bp;
873 
874 	if (vdp->xdf_state == XD_CONNECTED) {
875 		/*
876 		 * If we're in the XD_CONNECTED state, we only service IOs
877 		 * from the xdf_ready_tq_thread thread.
878 		 */
879 		if ((bp = vdp->xdf_ready_tq_bp) == NULL)
880 			return (NULL);
881 		if (((vreq = BP_VREQ(bp)) == NULL) || (!VREQ_DONE(vreq)))
882 			return (bp);
883 		return (NULL);
884 	}
885 
886 	/* if we're not in the XD_CONNECTED or XD_READY state we can't do IO */
887 	if (vdp->xdf_state != XD_READY)
888 		return (NULL);
889 
890 	ASSERT(vdp->xdf_ready_tq_bp == NULL);
891 	for (;;) {
892 		if ((bp = vdp->xdf_i_act) == NULL)
893 			return (NULL);
894 		if (((vreq = BP_VREQ(bp)) == NULL) || (!VREQ_DONE(vreq)))
895 			return (bp);
896 
897 		/* advance the active buf index pointer */
898 		vdp->xdf_i_act = bp->av_forw;
899 	}
900 }
901 
902 static void
903 xdf_io_fini(xdf_t *vdp, uint64_t id, int bioerr)
904 {
905 	ge_slot_t	*gs = (ge_slot_t *)(uintptr_t)id;
906 	v_req_t		*vreq = gs->gs_vreq;
907 	buf_t		*bp = vreq->v_buf;
908 
909 	ASSERT(MUTEX_HELD(&vdp->xdf_dev_lk));
910 	ASSERT(BP_VREQ(bp) == vreq);
911 
912 	gs_free(gs);
913 
914 	if (bioerr != 0)
915 		bioerror(bp, bioerr);
916 	ASSERT(vreq->v_nslots > 0);
917 	if (--vreq->v_nslots > 0)
918 		return;
919 
920 	/* remove this IO from our active queue */
921 	xdf_bp_pop(vdp, bp);
922 
923 	ASSERT(vreq->v_runq);
924 	xdf_kstat_exit(vdp, bp);
925 	vreq->v_runq = B_FALSE;
926 	vreq_free(vdp, vreq);
927 
928 	if (IS_ERROR(bp)) {
929 		xdf_io_err(bp, geterror(bp), 0);
930 	} else if (bp->b_resid != 0) {
931 		/* Partial transfers are an error */
932 		xdf_io_err(bp, EIO, bp->b_resid);
933 	} else {
934 		biodone(bp);
935 	}
936 }
937 
938 /*
939  * xdf interrupt handler
940  */
941 static uint_t
942 xdf_intr_locked(xdf_t *vdp)
943 {
944 	xendev_ring_t *xbr;
945 	blkif_response_t *resp;
946 	int bioerr;
947 	uint64_t id;
948 	uint8_t op;
949 	uint16_t status;
950 	ddi_acc_handle_t acchdl;
951 
952 	ASSERT(MUTEX_HELD(&vdp->xdf_dev_lk));
953 
954 	if ((xbr = vdp->xdf_xb_ring) == NULL)
955 		return (DDI_INTR_UNCLAIMED);
956 
957 	acchdl = vdp->xdf_xb_ring_hdl;
958 
959 	/*
960 	 * complete all requests which have a response
961 	 */
962 	while (resp = xvdi_ring_get_response(xbr)) {
963 		id = ddi_get64(acchdl, &resp->id);
964 		op = ddi_get8(acchdl, &resp->operation);
965 		status = ddi_get16(acchdl, (uint16_t *)&resp->status);
966 		DPRINTF(INTR_DBG, ("resp: op %d id %"PRIu64" status %d\n",
967 		    op, id, status));
968 
969 		if (status != BLKIF_RSP_OKAY) {
970 			DPRINTF(IO_DBG, ("xdf@%s: I/O error while %s",
971 			    vdp->xdf_addr,
972 			    (op == BLKIF_OP_READ) ? "reading" : "writing"));
973 			bioerr = EIO;
974 		} else {
975 			bioerr = 0;
976 		}
977 
978 		xdf_io_fini(vdp, id, bioerr);
979 	}
980 	return (DDI_INTR_CLAIMED);
981 }
982 
983 /*
984  * xdf_intr runs at PIL 5, so no one else can grab xdf_dev_lk and
985  * block at a lower pil.
986  */
987 static uint_t
988 xdf_intr(caddr_t arg)
989 {
990 	xdf_t *vdp = (xdf_t *)arg;
991 	int rv;
992 
993 	mutex_enter(&vdp->xdf_dev_lk);
994 	rv = xdf_intr_locked(vdp);
995 	mutex_exit(&vdp->xdf_dev_lk);
996 
997 	if (!do_polled_io)
998 		xdf_io_start(vdp);
999 
1000 	return (rv);
1001 }
1002 
1003 static void
1004 xdf_ring_push(xdf_t *vdp)
1005 {
1006 	ASSERT(MUTEX_HELD(&vdp->xdf_dev_lk));
1007 
1008 	if (vdp->xdf_xb_ring == NULL)
1009 		return;
1010 
1011 	if (xvdi_ring_push_request(vdp->xdf_xb_ring)) {
1012 		DPRINTF(IO_DBG, (
1013 		    "xdf@%s: xdf_ring_push: sent request(s) to backend\n",
1014 		    vdp->xdf_addr));
1015 	}
1016 
1017 	if (xvdi_get_evtchn(vdp->xdf_dip) != INVALID_EVTCHN)
1018 		xvdi_notify_oe(vdp->xdf_dip);
1019 }
1020 
1021 static int
1022 xdf_ring_drain_locked(xdf_t *vdp)
1023 {
1024 	int		pollc, rv = 0;
1025 
1026 	ASSERT(MUTEX_HELD(&vdp->xdf_dev_lk));
1027 
1028 	if (xdf_debug & SUSRES_DBG)
1029 		xen_printf("xdf_ring_drain: start\n");
1030 
1031 	for (pollc = 0; pollc < XDF_DRAIN_RETRY_COUNT; pollc++) {
1032 		if (vdp->xdf_xb_ring == NULL)
1033 			goto out;
1034 
1035 		if (xvdi_ring_has_unconsumed_responses(vdp->xdf_xb_ring))
1036 			(void) xdf_intr_locked(vdp);
1037 		if (!xvdi_ring_has_incomp_request(vdp->xdf_xb_ring))
1038 			goto out;
1039 		xdf_ring_push(vdp);
1040 
1041 		/* file-backed devices can be slow */
1042 		mutex_exit(&vdp->xdf_dev_lk);
1043 #ifdef XPV_HVM_DRIVER
1044 		(void) HYPERVISOR_yield();
1045 #endif /* XPV_HVM_DRIVER */
1046 		delay(drv_usectohz(XDF_DRAIN_MSEC_DELAY));
1047 		mutex_enter(&vdp->xdf_dev_lk);
1048 	}
1049 	cmn_err(CE_WARN, "xdf@%s: xdf_ring_drain: timeout", vdp->xdf_addr);
1050 
1051 out:
1052 	if (vdp->xdf_xb_ring != NULL) {
1053 		if (xvdi_ring_has_incomp_request(vdp->xdf_xb_ring) ||
1054 		    xvdi_ring_has_unconsumed_responses(vdp->xdf_xb_ring))
1055 			rv = EIO;
1056 	}
1057 	if (xdf_debug & SUSRES_DBG)
1058 		xen_printf("xdf@%s: xdf_ring_drain: end, err=%d\n",
1059 		    vdp->xdf_addr, rv);
1060 	return (rv);
1061 }
1062 
1063 static int
1064 xdf_ring_drain(xdf_t *vdp)
1065 {
1066 	int rv;
1067 	mutex_enter(&vdp->xdf_dev_lk);
1068 	rv = xdf_ring_drain_locked(vdp);
1069 	mutex_exit(&vdp->xdf_dev_lk);
1070 	return (rv);
1071 }
1072 
1073 /*
1074  * Destroy all v_req_t, grant table entries, and our ring buffer.
1075  */
1076 static void
1077 xdf_ring_destroy(xdf_t *vdp)
1078 {
1079 	v_req_t		*vreq;
1080 	buf_t		*bp;
1081 	ge_slot_t	*gs;
1082 
1083 	ASSERT(MUTEX_HELD(&vdp->xdf_cb_lk));
1084 	ASSERT(MUTEX_HELD(&vdp->xdf_dev_lk));
1085 
1086 	if ((vdp->xdf_state != XD_INIT) &&
1087 	    (vdp->xdf_state != XD_CONNECTED) &&
1088 	    (vdp->xdf_state != XD_READY)) {
1089 		ASSERT(vdp->xdf_xb_ring == NULL);
1090 		ASSERT(vdp->xdf_xb_ring_hdl == NULL);
1091 		ASSERT(vdp->xdf_peer == INVALID_DOMID);
1092 		ASSERT(vdp->xdf_evtchn == INVALID_EVTCHN);
1093 		ASSERT(list_is_empty(&vdp->xdf_vreq_act));
1094 		return;
1095 	}
1096 
1097 	/*
1098 	 * We don't want to recieve async notifications from the backend
1099 	 * when it finishes processing ring entries.
1100 	 */
1101 #ifdef XPV_HVM_DRIVER
1102 	ec_unbind_evtchn(vdp->xdf_evtchn);
1103 #else /* !XPV_HVM_DRIVER */
1104 	(void) ddi_remove_intr(vdp->xdf_dip, 0, NULL);
1105 #endif /* !XPV_HVM_DRIVER */
1106 
1107 	/*
1108 	 * Drain any requests in the ring.  We need to do this before we
1109 	 * can free grant table entries, because if active ring entries
1110 	 * point to grants, then the backend could be trying to access
1111 	 * those grants.
1112 	 */
1113 	(void) xdf_ring_drain_locked(vdp);
1114 
1115 	/* We're done talking to the backend so free up our event channel */
1116 	xvdi_free_evtchn(vdp->xdf_dip);
1117 	vdp->xdf_evtchn = INVALID_EVTCHN;
1118 
1119 	while ((vreq = list_head(&vdp->xdf_vreq_act)) != NULL) {
1120 		bp = vreq->v_buf;
1121 		ASSERT(BP_VREQ(bp) == vreq);
1122 
1123 		/* Free up any grant table entries associaed with this IO */
1124 		while ((gs = list_head(&vreq->v_gs)) != NULL)
1125 			gs_free(gs);
1126 
1127 		/* If this IO was on the runq, move it back to the waitq. */
1128 		if (vreq->v_runq)
1129 			xdf_kstat_runq_to_waitq(vdp, bp);
1130 
1131 		/*
1132 		 * Reset any buf IO state since we're going to re-issue the
1133 		 * IO when we reconnect.
1134 		 */
1135 		vreq_free(vdp, vreq);
1136 		BP_VREQ_SET(bp, NULL);
1137 		bioerror(bp, 0);
1138 	}
1139 
1140 	/* reset the active queue index pointer */
1141 	vdp->xdf_i_act = vdp->xdf_f_act;
1142 
1143 	/* Destroy the ring */
1144 	xvdi_free_ring(vdp->xdf_xb_ring);
1145 	vdp->xdf_xb_ring = NULL;
1146 	vdp->xdf_xb_ring_hdl = NULL;
1147 	vdp->xdf_peer = INVALID_DOMID;
1148 }
1149 
1150 void
1151 xdfmin(struct buf *bp)
1152 {
1153 	if (bp->b_bcount > xdf_maxphys)
1154 		bp->b_bcount = xdf_maxphys;
1155 }
1156 
1157 /*
1158  * Check if we have a pending "eject" media request.
1159  */
1160 static int
1161 xdf_eject_pending(xdf_t *vdp)
1162 {
1163 	dev_info_t	*dip = vdp->xdf_dip;
1164 	char		*xsname, *str;
1165 
1166 	if (!vdp->xdf_media_req_supported)
1167 		return (B_FALSE);
1168 
1169 	if (((xsname = xvdi_get_xsname(dip)) == NULL) ||
1170 	    (xenbus_read_str(xsname, XBP_MEDIA_REQ, &str) != 0))
1171 		return (B_FALSE);
1172 
1173 	if (strcmp(str, XBV_MEDIA_REQ_EJECT) != 0) {
1174 		strfree(str);
1175 		return (B_FALSE);
1176 	}
1177 	strfree(str);
1178 	return (B_TRUE);
1179 }
1180 
1181 /*
1182  * Generate a media request.
1183  */
1184 static int
1185 xdf_media_req(xdf_t *vdp, char *req, boolean_t media_required)
1186 {
1187 	dev_info_t	*dip = vdp->xdf_dip;
1188 	char		*xsname;
1189 
1190 	/*
1191 	 * we can't be holding xdf_dev_lk because xenbus_printf() can
1192 	 * block while waiting for a PIL 1 interrupt message.  this
1193 	 * would cause a deadlock with xdf_intr() which needs to grab
1194 	 * xdf_dev_lk as well and runs at PIL 5.
1195 	 */
1196 	ASSERT(MUTEX_HELD(&vdp->xdf_cb_lk));
1197 	ASSERT(MUTEX_NOT_HELD(&vdp->xdf_dev_lk));
1198 
1199 	if ((xsname = xvdi_get_xsname(dip)) == NULL)
1200 		return (ENXIO);
1201 
1202 	/* Check if we support media requests */
1203 	if (!XD_IS_CD(vdp) || !vdp->xdf_media_req_supported)
1204 		return (ENOTTY);
1205 
1206 	/* If an eject is pending then don't allow any new requests */
1207 	if (xdf_eject_pending(vdp))
1208 		return (ENXIO);
1209 
1210 	/* Make sure that there is media present */
1211 	if (media_required && (vdp->xdf_xdev_nblocks == 0))
1212 		return (ENXIO);
1213 
1214 	/* We only allow operations when the device is ready and connected */
1215 	if (vdp->xdf_state != XD_READY)
1216 		return (EIO);
1217 
1218 	if (xenbus_printf(XBT_NULL, xsname, XBP_MEDIA_REQ, "%s", req) != 0)
1219 		return (EIO);
1220 
1221 	return (0);
1222 }
1223 
1224 /*
1225  * populate a single blkif_request_t w/ a buf
1226  */
1227 static void
1228 xdf_process_rreq(xdf_t *vdp, struct buf *bp, blkif_request_t *rreq)
1229 {
1230 	grant_ref_t	gr;
1231 	uint8_t		fsect, lsect;
1232 	size_t		bcnt;
1233 	paddr_t		dma_addr;
1234 	off_t		blk_off;
1235 	dev_info_t	*dip = vdp->xdf_dip;
1236 	blkif_vdev_t	vdev = xvdi_get_vdevnum(dip);
1237 	v_req_t		*vreq = BP_VREQ(bp);
1238 	uint64_t	blkno = vreq->v_blkno;
1239 	uint_t		ndmacs = vreq->v_ndmacs;
1240 	ddi_acc_handle_t acchdl = vdp->xdf_xb_ring_hdl;
1241 	int		seg = 0;
1242 	int		isread = IS_READ(bp);
1243 	ge_slot_t	*gs = list_head(&vreq->v_gs);
1244 
1245 	ASSERT(MUTEX_HELD(&vdp->xdf_dev_lk));
1246 	ASSERT(vreq->v_status == VREQ_GS_ALLOCED);
1247 
1248 	if (isread)
1249 		ddi_put8(acchdl, &rreq->operation, BLKIF_OP_READ);
1250 	else {
1251 		switch (vreq->v_flush_diskcache) {
1252 		case FLUSH_DISKCACHE:
1253 			ddi_put8(acchdl, &rreq->operation,
1254 			    BLKIF_OP_FLUSH_DISKCACHE);
1255 			ddi_put16(acchdl, &rreq->handle, vdev);
1256 			ddi_put64(acchdl, &rreq->id,
1257 			    (uint64_t)(uintptr_t)(gs));
1258 			ddi_put8(acchdl, &rreq->nr_segments, 0);
1259 			vreq->v_status = VREQ_DMAWIN_DONE;
1260 			return;
1261 		case WRITE_BARRIER:
1262 			ddi_put8(acchdl, &rreq->operation,
1263 			    BLKIF_OP_WRITE_BARRIER);
1264 			break;
1265 		default:
1266 			if (!vdp->xdf_wce)
1267 				ddi_put8(acchdl, &rreq->operation,
1268 				    BLKIF_OP_WRITE_BARRIER);
1269 			else
1270 				ddi_put8(acchdl, &rreq->operation,
1271 				    BLKIF_OP_WRITE);
1272 			break;
1273 		}
1274 	}
1275 
1276 	ddi_put16(acchdl, &rreq->handle, vdev);
1277 	ddi_put64(acchdl, &rreq->sector_number, blkno);
1278 	ddi_put64(acchdl, &rreq->id, (uint64_t)(uintptr_t)(gs));
1279 
1280 	/*
1281 	 * loop until all segments are populated or no more dma cookie in buf
1282 	 */
1283 	for (;;) {
1284 		/*
1285 		 * Each segment of a blkif request can transfer up to
1286 		 * one 4K page of data.
1287 		 */
1288 		bcnt = vreq->v_dmac.dmac_size;
1289 		dma_addr = vreq->v_dmac.dmac_laddress;
1290 		blk_off = (uint_t)((paddr_t)XB_SEGOFFSET & dma_addr);
1291 		fsect = blk_off >> XB_BSHIFT;
1292 		lsect = fsect + (bcnt >> XB_BSHIFT) - 1;
1293 
1294 		ASSERT(bcnt <= PAGESIZE);
1295 		ASSERT((bcnt % XB_BSIZE) == 0);
1296 		ASSERT((blk_off & XB_BMASK) == 0);
1297 		ASSERT(fsect < XB_MAX_SEGLEN / XB_BSIZE &&
1298 		    lsect < XB_MAX_SEGLEN / XB_BSIZE);
1299 
1300 		gr = gs_grant(gs, PATOMA(dma_addr) >> PAGESHIFT);
1301 		ddi_put32(acchdl, &rreq->seg[seg].gref, gr);
1302 		ddi_put8(acchdl, &rreq->seg[seg].first_sect, fsect);
1303 		ddi_put8(acchdl, &rreq->seg[seg].last_sect, lsect);
1304 
1305 		DPRINTF(IO_DBG, (
1306 		    "xdf@%s: seg%d: dmacS %lu blk_off %ld\n",
1307 		    vdp->xdf_addr, seg, vreq->v_dmac.dmac_size, blk_off));
1308 		DPRINTF(IO_DBG, (
1309 		    "xdf@%s: seg%d: fs %d ls %d gr %d dma 0x%"PRIx64"\n",
1310 		    vdp->xdf_addr, seg, fsect, lsect, gr, dma_addr));
1311 
1312 		blkno += (bcnt >> XB_BSHIFT);
1313 		seg++;
1314 		ASSERT(seg <= BLKIF_MAX_SEGMENTS_PER_REQUEST);
1315 		if (--ndmacs) {
1316 			ddi_dma_nextcookie(vreq->v_dmahdl, &vreq->v_dmac);
1317 			continue;
1318 		}
1319 
1320 		vreq->v_status = VREQ_DMAWIN_DONE;
1321 		vreq->v_blkno = blkno;
1322 		break;
1323 	}
1324 	ddi_put8(acchdl,  &rreq->nr_segments, seg);
1325 	DPRINTF(IO_DBG, (
1326 	    "xdf@%s: xdf_process_rreq: request id=%"PRIx64" ready\n",
1327 	    vdp->xdf_addr, rreq->id));
1328 }
1329 
1330 static void
1331 xdf_io_start(xdf_t *vdp)
1332 {
1333 	struct buf	*bp;
1334 	v_req_t		*vreq;
1335 	blkif_request_t	*rreq;
1336 	boolean_t	rreqready = B_FALSE;
1337 
1338 	mutex_enter(&vdp->xdf_dev_lk);
1339 
1340 	/*
1341 	 * Populate the ring request(s).  Loop until there is no buf to
1342 	 * transfer or no free slot available in I/O ring.
1343 	 */
1344 	for (;;) {
1345 		/* don't start any new IO if we're suspending */
1346 		if (vdp->xdf_suspending)
1347 			break;
1348 		if ((bp = xdf_bp_next(vdp)) == NULL)
1349 			break;
1350 
1351 		/* if the buf doesn't already have a vreq, allocate one */
1352 		if (((vreq = BP_VREQ(bp)) == NULL) &&
1353 		    ((vreq = vreq_get(vdp, bp)) == NULL))
1354 			break;
1355 
1356 		/* alloc DMA/GTE resources */
1357 		if (vreq_setup(vdp, vreq) != DDI_SUCCESS)
1358 			break;
1359 
1360 		/* get next blkif_request in the ring */
1361 		if ((rreq = xvdi_ring_get_request(vdp->xdf_xb_ring)) == NULL)
1362 			break;
1363 		bzero(rreq, sizeof (blkif_request_t));
1364 		rreqready = B_TRUE;
1365 
1366 		/* populate blkif_request with this buf */
1367 		xdf_process_rreq(vdp, bp, rreq);
1368 
1369 		/*
1370 		 * This buffer/vreq pair is has been allocated a ring buffer
1371 		 * resources, so if it isn't already in our runq, add it.
1372 		 */
1373 		if (!vreq->v_runq)
1374 			xdf_kstat_waitq_to_runq(vdp, bp);
1375 	}
1376 
1377 	/* Send the request(s) to the backend */
1378 	if (rreqready)
1379 		xdf_ring_push(vdp);
1380 
1381 	mutex_exit(&vdp->xdf_dev_lk);
1382 }
1383 
1384 
1385 /* check if partition is open, -1 - check all partitions on the disk */
1386 static boolean_t
1387 xdf_isopen(xdf_t *vdp, int partition)
1388 {
1389 	int i;
1390 	ulong_t parbit;
1391 	boolean_t rval = B_FALSE;
1392 
1393 	ASSERT((partition == -1) ||
1394 	    ((partition >= 0) || (partition < XDF_PEXT)));
1395 
1396 	if (partition == -1)
1397 		parbit = (ulong_t)-1;
1398 	else
1399 		parbit = 1 << partition;
1400 
1401 	for (i = 0; i < OTYPCNT; i++) {
1402 		if (vdp->xdf_vd_open[i] & parbit)
1403 			rval = B_TRUE;
1404 	}
1405 
1406 	return (rval);
1407 }
1408 
1409 /*
1410  * The connection should never be closed as long as someone is holding
1411  * us open, there is pending IO, or someone is waiting waiting for a
1412  * connection.
1413  */
1414 static boolean_t
1415 xdf_busy(xdf_t *vdp)
1416 {
1417 	ASSERT(MUTEX_HELD(&vdp->xdf_dev_lk));
1418 
1419 	if ((vdp->xdf_xb_ring != NULL) &&
1420 	    xvdi_ring_has_unconsumed_responses(vdp->xdf_xb_ring)) {
1421 		ASSERT(vdp->xdf_state != XD_CLOSED);
1422 		return (B_TRUE);
1423 	}
1424 
1425 	if (!list_is_empty(&vdp->xdf_vreq_act) || (vdp->xdf_f_act != NULL)) {
1426 		ASSERT(vdp->xdf_state != XD_CLOSED);
1427 		return (B_TRUE);
1428 	}
1429 
1430 	if (xdf_isopen(vdp, -1)) {
1431 		ASSERT(vdp->xdf_state != XD_CLOSED);
1432 		return (B_TRUE);
1433 	}
1434 
1435 	if (vdp->xdf_connect_req > 0) {
1436 		ASSERT(vdp->xdf_state != XD_CLOSED);
1437 		return (B_TRUE);
1438 	}
1439 
1440 	return (B_FALSE);
1441 }
1442 
1443 static void
1444 xdf_set_state(xdf_t *vdp, xdf_state_t new_state)
1445 {
1446 	ASSERT(MUTEX_HELD(&vdp->xdf_cb_lk));
1447 	ASSERT(MUTEX_HELD(&vdp->xdf_dev_lk));
1448 	DPRINTF(DDI_DBG, ("xdf@%s: state change %d -> %d\n",
1449 	    vdp->xdf_addr, vdp->xdf_state, new_state));
1450 	vdp->xdf_state = new_state;
1451 	cv_broadcast(&vdp->xdf_dev_cv);
1452 }
1453 
1454 static void
1455 xdf_disconnect(xdf_t *vdp, xdf_state_t new_state, boolean_t quiet)
1456 {
1457 	dev_info_t	*dip = vdp->xdf_dip;
1458 	boolean_t	busy;
1459 
1460 	ASSERT(MUTEX_HELD(&vdp->xdf_cb_lk));
1461 	ASSERT(MUTEX_NOT_HELD(&vdp->xdf_dev_lk));
1462 	ASSERT((new_state == XD_UNKNOWN) || (new_state == XD_CLOSED));
1463 
1464 	/* Check if we're already there. */
1465 	if (vdp->xdf_state == new_state)
1466 		return;
1467 
1468 	mutex_enter(&vdp->xdf_dev_lk);
1469 	busy = xdf_busy(vdp);
1470 
1471 	/* If we're already closed then there's nothing todo. */
1472 	if (vdp->xdf_state == XD_CLOSED) {
1473 		ASSERT(!busy);
1474 		xdf_set_state(vdp, new_state);
1475 		mutex_exit(&vdp->xdf_dev_lk);
1476 		return;
1477 	}
1478 
1479 #ifdef DEBUG
1480 	/* UhOh.  Warn the user that something bad has happened. */
1481 	if (!quiet && busy && (vdp->xdf_state == XD_READY) &&
1482 	    (vdp->xdf_xdev_nblocks != 0)) {
1483 		cmn_err(CE_WARN, "xdf@%s: disconnected while in use",
1484 		    vdp->xdf_addr);
1485 	}
1486 #endif /* DEBUG */
1487 
1488 	xdf_ring_destroy(vdp);
1489 
1490 	/* If we're busy then we can only go into the unknown state */
1491 	xdf_set_state(vdp, (busy) ? XD_UNKNOWN : new_state);
1492 	mutex_exit(&vdp->xdf_dev_lk);
1493 
1494 	/* if we're closed now, let the other end know */
1495 	if (vdp->xdf_state == XD_CLOSED)
1496 		(void) xvdi_switch_state(dip, XBT_NULL, XenbusStateClosed);
1497 }
1498 
1499 
1500 /*
1501  * Kick-off connect process
1502  * Status should be XD_UNKNOWN or XD_CLOSED
1503  * On success, status will be changed to XD_INIT
1504  * On error, it will be changed to XD_UNKNOWN
1505  */
1506 static int
1507 xdf_setstate_init(xdf_t *vdp)
1508 {
1509 	dev_info_t		*dip = vdp->xdf_dip;
1510 	xenbus_transaction_t	xbt;
1511 	grant_ref_t		gref;
1512 	char			*xsname, *str;
1513 	int 			rv;
1514 
1515 	ASSERT(MUTEX_HELD(&vdp->xdf_cb_lk));
1516 	ASSERT(MUTEX_NOT_HELD(&vdp->xdf_dev_lk));
1517 	ASSERT((vdp->xdf_state == XD_UNKNOWN) ||
1518 	    (vdp->xdf_state == XD_CLOSED));
1519 
1520 	DPRINTF(DDI_DBG,
1521 	    ("xdf@%s: starting connection process\n", vdp->xdf_addr));
1522 
1523 	/*
1524 	 * If an eject is pending then don't allow a new connection.
1525 	 * (Only the backend can clear media request eject request.)
1526 	 */
1527 	if (xdf_eject_pending(vdp))
1528 		return (DDI_FAILURE);
1529 
1530 	if ((xsname = xvdi_get_xsname(dip)) == NULL)
1531 		goto errout;
1532 
1533 	if ((vdp->xdf_peer = xvdi_get_oeid(dip)) == INVALID_DOMID)
1534 		goto errout;
1535 
1536 	(void) xvdi_switch_state(dip, XBT_NULL, XenbusStateInitialising);
1537 
1538 	/*
1539 	 * Sanity check for the existance of the xenbus device-type property.
1540 	 * This property might not exist if we our xenbus device nodes was
1541 	 * force destroyed while we were still connected to the backend.
1542 	 */
1543 	if (xenbus_read_str(xsname, XBP_DEV_TYPE, &str) != 0)
1544 		goto errout;
1545 	strfree(str);
1546 
1547 	if (xvdi_alloc_evtchn(dip) != DDI_SUCCESS)
1548 		goto errout;
1549 
1550 	vdp->xdf_evtchn = xvdi_get_evtchn(dip);
1551 #ifdef XPV_HVM_DRIVER
1552 	ec_bind_evtchn_to_handler(vdp->xdf_evtchn, IPL_VBD, xdf_intr, vdp);
1553 #else /* !XPV_HVM_DRIVER */
1554 	if (ddi_add_intr(dip, 0, NULL, NULL, xdf_intr, (caddr_t)vdp) !=
1555 	    DDI_SUCCESS) {
1556 		cmn_err(CE_WARN, "xdf@%s: xdf_setstate_init: "
1557 		    "failed to add intr handler", vdp->xdf_addr);
1558 		goto errout1;
1559 	}
1560 #endif /* !XPV_HVM_DRIVER */
1561 
1562 	if (xvdi_alloc_ring(dip, BLKIF_RING_SIZE,
1563 	    sizeof (union blkif_sring_entry), &gref, &vdp->xdf_xb_ring) !=
1564 	    DDI_SUCCESS) {
1565 		cmn_err(CE_WARN, "xdf@%s: failed to alloc comm ring",
1566 		    vdp->xdf_addr);
1567 		goto errout2;
1568 	}
1569 	vdp->xdf_xb_ring_hdl = vdp->xdf_xb_ring->xr_acc_hdl; /* ugly!! */
1570 
1571 	/*
1572 	 * Write into xenstore the info needed by backend
1573 	 */
1574 trans_retry:
1575 	if (xenbus_transaction_start(&xbt)) {
1576 		cmn_err(CE_WARN, "xdf@%s: failed to start transaction",
1577 		    vdp->xdf_addr);
1578 		xvdi_fatal_error(dip, EIO, "connect transaction init");
1579 		goto fail_trans;
1580 	}
1581 
1582 	/*
1583 	 * XBP_PROTOCOL is written by the domain builder in the case of PV
1584 	 * domains. However, it is not written for HVM domains, so let's
1585 	 * write it here.
1586 	 */
1587 	if (((rv = xenbus_printf(xbt, xsname,
1588 	    XBP_MEDIA_REQ, "%s", XBV_MEDIA_REQ_NONE)) != 0) ||
1589 	    ((rv = xenbus_printf(xbt, xsname,
1590 	    XBP_RING_REF, "%u", gref)) != 0) ||
1591 	    ((rv = xenbus_printf(xbt, xsname,
1592 	    XBP_EVENT_CHAN, "%u", vdp->xdf_evtchn)) != 0) ||
1593 	    ((rv = xenbus_printf(xbt, xsname,
1594 	    XBP_PROTOCOL, "%s", XEN_IO_PROTO_ABI_NATIVE)) != 0) ||
1595 	    ((rv = xvdi_switch_state(dip, xbt, XenbusStateInitialised)) > 0)) {
1596 		(void) xenbus_transaction_end(xbt, 1);
1597 		xvdi_fatal_error(dip, rv, "connect transaction setup");
1598 		goto fail_trans;
1599 	}
1600 
1601 	/* kick-off connect process */
1602 	if (rv = xenbus_transaction_end(xbt, 0)) {
1603 		if (rv == EAGAIN)
1604 			goto trans_retry;
1605 		xvdi_fatal_error(dip, rv, "connect transaction commit");
1606 		goto fail_trans;
1607 	}
1608 
1609 	ASSERT(MUTEX_HELD(&vdp->xdf_cb_lk));
1610 	mutex_enter(&vdp->xdf_dev_lk);
1611 	xdf_set_state(vdp, XD_INIT);
1612 	mutex_exit(&vdp->xdf_dev_lk);
1613 
1614 	return (DDI_SUCCESS);
1615 
1616 fail_trans:
1617 	xvdi_free_ring(vdp->xdf_xb_ring);
1618 errout2:
1619 #ifdef XPV_HVM_DRIVER
1620 	ec_unbind_evtchn(vdp->xdf_evtchn);
1621 #else /* !XPV_HVM_DRIVER */
1622 	(void) ddi_remove_intr(vdp->xdf_dip, 0, NULL);
1623 #endif /* !XPV_HVM_DRIVER */
1624 errout1:
1625 	xvdi_free_evtchn(dip);
1626 	vdp->xdf_evtchn = INVALID_EVTCHN;
1627 errout:
1628 	xdf_disconnect(vdp, XD_UNKNOWN, B_FALSE);
1629 	cmn_err(CE_WARN, "xdf@%s: failed to start connection to backend",
1630 	    vdp->xdf_addr);
1631 	return (DDI_FAILURE);
1632 }
1633 
1634 int
1635 xdf_get_flush_block(xdf_t *vdp)
1636 {
1637 	/*
1638 	 * Get a DEV_BSIZE aligned bufer
1639 	 */
1640 	vdp->xdf_flush_mem = kmem_alloc(vdp->xdf_xdev_secsize * 2, KM_SLEEP);
1641 	vdp->xdf_cache_flush_block =
1642 	    (char *)P2ROUNDUP((uintptr_t)(vdp->xdf_flush_mem),
1643 	    (int)vdp->xdf_xdev_secsize);
1644 
1645 	if (xdf_lb_rdwr(vdp->xdf_dip, TG_READ, vdp->xdf_cache_flush_block,
1646 	    xdf_flush_block, vdp->xdf_xdev_secsize, NULL) != 0)
1647 		return (DDI_FAILURE);
1648 	return (DDI_SUCCESS);
1649 }
1650 
1651 static void
1652 xdf_setstate_ready(void *arg)
1653 {
1654 	xdf_t	*vdp = (xdf_t *)arg;
1655 
1656 	vdp->xdf_ready_tq_thread = curthread;
1657 
1658 	/*
1659 	 * We've created all the minor nodes via cmlb_attach() using default
1660 	 * value in xdf_attach() to make it possible to block in xdf_open(),
1661 	 * in case there's anyone (say, booting thread) ever trying to open
1662 	 * it before connected to backend. We will refresh all those minor
1663 	 * nodes w/ latest info we've got now when we are almost connected.
1664 	 */
1665 	mutex_enter(&vdp->xdf_dev_lk);
1666 	if (vdp->xdf_cmbl_reattach) {
1667 		vdp->xdf_cmbl_reattach = B_FALSE;
1668 
1669 		mutex_exit(&vdp->xdf_dev_lk);
1670 		if (xdf_cmlb_attach(vdp) != 0) {
1671 			xdf_disconnect(vdp, XD_UNKNOWN, B_FALSE);
1672 			return;
1673 		}
1674 		mutex_enter(&vdp->xdf_dev_lk);
1675 	}
1676 
1677 	/* If we're not still trying to get to the ready state, then bail. */
1678 	if (vdp->xdf_state != XD_CONNECTED) {
1679 		mutex_exit(&vdp->xdf_dev_lk);
1680 		return;
1681 	}
1682 	mutex_exit(&vdp->xdf_dev_lk);
1683 
1684 	/*
1685 	 * If backend has feature-barrier, see if it supports disk
1686 	 * cache flush op.
1687 	 */
1688 	vdp->xdf_flush_supported = B_FALSE;
1689 	if (vdp->xdf_feature_barrier) {
1690 		/*
1691 		 * Pretend we already know flush is supported so probe
1692 		 * will attempt the correct op.
1693 		 */
1694 		vdp->xdf_flush_supported = B_TRUE;
1695 		if (xdf_lb_rdwr(vdp->xdf_dip, TG_WRITE, NULL, 0, 0, 0) == 0) {
1696 			vdp->xdf_flush_supported = B_TRUE;
1697 		} else {
1698 			vdp->xdf_flush_supported = B_FALSE;
1699 			/*
1700 			 * If the other end does not support the cache flush op
1701 			 * then we must use a barrier-write to force disk
1702 			 * cache flushing.  Barrier writes require that a data
1703 			 * block actually be written.
1704 			 * Cache a block to barrier-write when we are
1705 			 * asked to perform a flush.
1706 			 * XXX - would it be better to just copy 1 block
1707 			 * (512 bytes) from whatever write we did last
1708 			 * and rewrite that block?
1709 			 */
1710 			if (xdf_get_flush_block(vdp) != DDI_SUCCESS) {
1711 				xdf_disconnect(vdp, XD_UNKNOWN, B_FALSE);
1712 				return;
1713 			}
1714 		}
1715 	}
1716 
1717 	mutex_enter(&vdp->xdf_cb_lk);
1718 	mutex_enter(&vdp->xdf_dev_lk);
1719 	if (vdp->xdf_state == XD_CONNECTED)
1720 		xdf_set_state(vdp, XD_READY);
1721 	mutex_exit(&vdp->xdf_dev_lk);
1722 
1723 	/* Restart any currently queued up io */
1724 	xdf_io_start(vdp);
1725 
1726 	mutex_exit(&vdp->xdf_cb_lk);
1727 }
1728 
1729 /*
1730  * synthetic geometry
1731  */
1732 #define	XDF_NSECTS	256
1733 #define	XDF_NHEADS	16
1734 
1735 static void
1736 xdf_synthetic_pgeom(dev_info_t *dip, cmlb_geom_t *geomp)
1737 {
1738 	xdf_t *vdp;
1739 	uint_t ncyl;
1740 
1741 	vdp = ddi_get_soft_state(xdf_ssp, ddi_get_instance(dip));
1742 
1743 	ncyl = vdp->xdf_xdev_nblocks / (XDF_NHEADS * XDF_NSECTS);
1744 
1745 	bzero(geomp, sizeof (*geomp));
1746 	geomp->g_ncyl = ncyl == 0 ? 1 : ncyl;
1747 	geomp->g_acyl = 0;
1748 	geomp->g_nhead = XDF_NHEADS;
1749 	geomp->g_nsect = XDF_NSECTS;
1750 	geomp->g_secsize = vdp->xdf_xdev_secsize;
1751 	geomp->g_capacity = vdp->xdf_xdev_nblocks;
1752 	geomp->g_intrlv = 0;
1753 	geomp->g_rpm = 7200;
1754 }
1755 
1756 /*
1757  * Finish other initialization after we've connected to backend
1758  * Status should be XD_INIT before calling this routine
1759  * On success, status should be changed to XD_CONNECTED.
1760  * On error, status should stay XD_INIT
1761  */
1762 static int
1763 xdf_setstate_connected(xdf_t *vdp)
1764 {
1765 	dev_info_t	*dip = vdp->xdf_dip;
1766 	cmlb_geom_t	pgeom;
1767 	diskaddr_t	nblocks = 0;
1768 	uint_t		secsize = 0;
1769 	char		*oename, *xsname, *str;
1770 	uint_t		dinfo;
1771 
1772 	ASSERT(MUTEX_HELD(&vdp->xdf_cb_lk));
1773 	ASSERT(MUTEX_NOT_HELD(&vdp->xdf_dev_lk));
1774 	ASSERT(vdp->xdf_state == XD_INIT);
1775 
1776 	if (((xsname = xvdi_get_xsname(dip)) == NULL) ||
1777 	    ((oename = xvdi_get_oename(dip)) == NULL))
1778 		return (DDI_FAILURE);
1779 
1780 	/* Make sure the other end is XenbusStateConnected */
1781 	if (xenbus_read_driver_state(oename) != XenbusStateConnected)
1782 		return (DDI_FAILURE);
1783 
1784 	/* Determine if feature barrier is supported by backend */
1785 	if (!(vdp->xdf_feature_barrier = xenbus_exists(oename, XBP_FB)))
1786 		cmn_err(CE_NOTE, "!xdf@%s: feature-barrier not supported",
1787 		    vdp->xdf_addr);
1788 
1789 	/*
1790 	 * Probe backend.  Read the device size into xdf_xdev_nblocks
1791 	 * and set the VDISK_READONLY, VDISK_CDROM, and VDISK_REMOVABLE
1792 	 * flags in xdf_dinfo.  If the emulated device type is "cdrom",
1793 	 * we always set VDISK_CDROM, regardless of if it's present in
1794 	 * the xenbus info parameter.
1795 	 */
1796 	if (xenbus_gather(XBT_NULL, oename,
1797 	    XBP_SECTORS, "%"SCNu64, &nblocks,
1798 	    XBP_SECTOR_SIZE, "%u", &secsize,
1799 	    XBP_INFO, "%u", &dinfo,
1800 	    NULL) != 0) {
1801 		cmn_err(CE_WARN, "xdf@%s: xdf_setstate_connected: "
1802 		    "cannot read backend info", vdp->xdf_addr);
1803 		return (DDI_FAILURE);
1804 	}
1805 	if (xenbus_read_str(xsname, XBP_DEV_TYPE, &str) != 0) {
1806 		cmn_err(CE_WARN, "xdf@%s: cannot read device-type",
1807 		    vdp->xdf_addr);
1808 		return (DDI_FAILURE);
1809 	}
1810 	if (strcmp(str, XBV_DEV_TYPE_CD) == 0)
1811 		dinfo |= VDISK_CDROM;
1812 	strfree(str);
1813 
1814 	if (secsize == 0 || !(ISP2(secsize / DEV_BSIZE)))
1815 		secsize = DEV_BSIZE;
1816 	vdp->xdf_xdev_nblocks = nblocks;
1817 	vdp->xdf_xdev_secsize = secsize;
1818 #ifdef _ILP32
1819 	if (vdp->xdf_xdev_nblocks > DK_MAX_BLOCKS) {
1820 		cmn_err(CE_WARN, "xdf@%s: xdf_setstate_connected: "
1821 		    "backend disk device too large with %llu blocks for"
1822 		    " 32-bit kernel", vdp->xdf_addr, vdp->xdf_xdev_nblocks);
1823 		xvdi_fatal_error(dip, EFBIG, "reading backend info");
1824 		return (DDI_FAILURE);
1825 	}
1826 #endif
1827 
1828 	/*
1829 	 * If the physical geometry for a fixed disk has been explicity
1830 	 * set then make sure that the specified physical geometry isn't
1831 	 * larger than the device we connected to.
1832 	 */
1833 	if (vdp->xdf_pgeom_fixed &&
1834 	    (vdp->xdf_pgeom.g_capacity > vdp->xdf_xdev_nblocks)) {
1835 		cmn_err(CE_WARN,
1836 		    "xdf@%s: connect failed, fixed geometry too large",
1837 		    vdp->xdf_addr);
1838 		return (DDI_FAILURE);
1839 	}
1840 
1841 	vdp->xdf_media_req_supported = xenbus_exists(oename, XBP_MEDIA_REQ_SUP);
1842 
1843 	/* mark vbd is ready for I/O */
1844 	mutex_enter(&vdp->xdf_dev_lk);
1845 	xdf_set_state(vdp, XD_CONNECTED);
1846 
1847 	/* check if the cmlb label should be updated */
1848 	xdf_synthetic_pgeom(dip, &pgeom);
1849 	if ((vdp->xdf_dinfo != dinfo) ||
1850 	    (!vdp->xdf_pgeom_fixed &&
1851 	    (memcmp(&vdp->xdf_pgeom, &pgeom, sizeof (pgeom)) != 0))) {
1852 		vdp->xdf_cmbl_reattach = B_TRUE;
1853 
1854 		vdp->xdf_dinfo = dinfo;
1855 		if (!vdp->xdf_pgeom_fixed)
1856 			vdp->xdf_pgeom = pgeom;
1857 	}
1858 
1859 	if (XD_IS_CD(vdp) || XD_IS_RM(vdp)) {
1860 		if (vdp->xdf_xdev_nblocks == 0) {
1861 			vdp->xdf_mstate = DKIO_EJECTED;
1862 			cv_broadcast(&vdp->xdf_mstate_cv);
1863 		} else {
1864 			vdp->xdf_mstate = DKIO_INSERTED;
1865 			cv_broadcast(&vdp->xdf_mstate_cv);
1866 		}
1867 	} else {
1868 		if (vdp->xdf_mstate != DKIO_NONE) {
1869 			vdp->xdf_mstate = DKIO_NONE;
1870 			cv_broadcast(&vdp->xdf_mstate_cv);
1871 		}
1872 	}
1873 
1874 	mutex_exit(&vdp->xdf_dev_lk);
1875 
1876 	cmn_err(CE_CONT, "?xdf@%s: %"PRIu64" blocks", vdp->xdf_addr,
1877 	    (uint64_t)vdp->xdf_xdev_nblocks);
1878 
1879 	/* Restart any currently queued up io */
1880 	xdf_io_start(vdp);
1881 
1882 	/*
1883 	 * To get to the ready state we have to do IO to the backend device,
1884 	 * but we can't initiate IO from the other end change callback thread
1885 	 * (which is the current context we're executing in.)  This is because
1886 	 * if the other end disconnects while we're doing IO from the callback
1887 	 * thread, then we can't recieve that disconnect event and we hang
1888 	 * waiting for an IO that can never complete.
1889 	 */
1890 	(void) ddi_taskq_dispatch(vdp->xdf_ready_tq, xdf_setstate_ready, vdp,
1891 	    DDI_SLEEP);
1892 
1893 	(void) xvdi_switch_state(dip, XBT_NULL, XenbusStateConnected);
1894 	return (DDI_SUCCESS);
1895 }
1896 
1897 /*ARGSUSED*/
1898 static void
1899 xdf_oe_change(dev_info_t *dip, ddi_eventcookie_t id, void *arg, void *impl_data)
1900 {
1901 	XenbusState new_state = *(XenbusState *)impl_data;
1902 	xdf_t *vdp = (xdf_t *)ddi_get_driver_private(dip);
1903 
1904 	DPRINTF(DDI_DBG, ("xdf@%s: otherend state change to %d!\n",
1905 	    vdp->xdf_addr, new_state));
1906 
1907 	mutex_enter(&vdp->xdf_cb_lk);
1908 
1909 	/* We assume that this callback is single threaded */
1910 	ASSERT(vdp->xdf_oe_change_thread == NULL);
1911 	DEBUG_EVAL(vdp->xdf_oe_change_thread = curthread);
1912 
1913 	/* ignore any backend state changes if we're suspending/suspended */
1914 	if (vdp->xdf_suspending || (vdp->xdf_state == XD_SUSPEND)) {
1915 		DEBUG_EVAL(vdp->xdf_oe_change_thread = NULL);
1916 		mutex_exit(&vdp->xdf_cb_lk);
1917 		return;
1918 	}
1919 
1920 	switch (new_state) {
1921 	case XenbusStateUnknown:
1922 	case XenbusStateInitialising:
1923 	case XenbusStateInitWait:
1924 	case XenbusStateInitialised:
1925 		if (vdp->xdf_state == XD_INIT)
1926 			break;
1927 
1928 		xdf_disconnect(vdp, XD_UNKNOWN, B_FALSE);
1929 		if (xdf_setstate_init(vdp) != DDI_SUCCESS)
1930 			break;
1931 		ASSERT(vdp->xdf_state == XD_INIT);
1932 		break;
1933 
1934 	case XenbusStateConnected:
1935 		if ((vdp->xdf_state == XD_CONNECTED) ||
1936 		    (vdp->xdf_state == XD_READY))
1937 			break;
1938 
1939 		if (vdp->xdf_state != XD_INIT) {
1940 			xdf_disconnect(vdp, XD_UNKNOWN, B_FALSE);
1941 			if (xdf_setstate_init(vdp) != DDI_SUCCESS)
1942 				break;
1943 			ASSERT(vdp->xdf_state == XD_INIT);
1944 		}
1945 
1946 		if (xdf_setstate_connected(vdp) != DDI_SUCCESS) {
1947 			xdf_disconnect(vdp, XD_UNKNOWN, B_FALSE);
1948 			break;
1949 		}
1950 		ASSERT(vdp->xdf_state == XD_CONNECTED);
1951 		break;
1952 
1953 	case XenbusStateClosing:
1954 		if (xdf_isopen(vdp, -1)) {
1955 			cmn_err(CE_NOTE,
1956 			    "xdf@%s: hot-unplug failed, still in use",
1957 			    vdp->xdf_addr);
1958 			break;
1959 		}
1960 		/*FALLTHROUGH*/
1961 	case XenbusStateClosed:
1962 		xdf_disconnect(vdp, XD_CLOSED, B_FALSE);
1963 		break;
1964 	}
1965 
1966 	/* notify anybody waiting for oe state change */
1967 	cv_broadcast(&vdp->xdf_dev_cv);
1968 	DEBUG_EVAL(vdp->xdf_oe_change_thread = NULL);
1969 	mutex_exit(&vdp->xdf_cb_lk);
1970 }
1971 
1972 static int
1973 xdf_connect_locked(xdf_t *vdp, boolean_t wait)
1974 {
1975 	int	rv, timeouts = 0, reset = 20;
1976 
1977 	ASSERT(MUTEX_HELD(&vdp->xdf_cb_lk));
1978 	ASSERT(MUTEX_HELD(&vdp->xdf_dev_lk));
1979 
1980 	/* we can't connect once we're in the closed state */
1981 	if (vdp->xdf_state == XD_CLOSED)
1982 		return (XD_CLOSED);
1983 
1984 	vdp->xdf_connect_req++;
1985 	while (vdp->xdf_state != XD_READY) {
1986 		mutex_exit(&vdp->xdf_dev_lk);
1987 
1988 		/* only one thread at a time can be the connection thread */
1989 		if (vdp->xdf_connect_thread == NULL)
1990 			vdp->xdf_connect_thread = curthread;
1991 
1992 		if (vdp->xdf_connect_thread == curthread) {
1993 			if ((timeouts > 0) && ((timeouts % reset) == 0)) {
1994 				/*
1995 				 * If we haven't establised a connection
1996 				 * within the reset time, then disconnect
1997 				 * so we can try again, and double the reset
1998 				 * time.  The reset time starts at 2 sec.
1999 				 */
2000 				(void) xdf_disconnect(vdp, XD_UNKNOWN, B_TRUE);
2001 				reset *= 2;
2002 			}
2003 			if (vdp->xdf_state == XD_UNKNOWN)
2004 				(void) xdf_setstate_init(vdp);
2005 			if (vdp->xdf_state == XD_INIT)
2006 				(void) xdf_setstate_connected(vdp);
2007 		}
2008 
2009 		mutex_enter(&vdp->xdf_dev_lk);
2010 		if (!wait || (vdp->xdf_state == XD_READY))
2011 			goto out;
2012 
2013 		mutex_exit((&vdp->xdf_cb_lk));
2014 		if (vdp->xdf_connect_thread != curthread) {
2015 			rv = cv_wait_sig(&vdp->xdf_dev_cv, &vdp->xdf_dev_lk);
2016 		} else {
2017 			/* delay for 0.1 sec */
2018 			rv = cv_timedwait_sig(&vdp->xdf_dev_cv,
2019 			    &vdp->xdf_dev_lk, lbolt + drv_usectohz(100*1000));
2020 			if (rv == -1)
2021 				timeouts++;
2022 		}
2023 		mutex_exit((&vdp->xdf_dev_lk));
2024 		mutex_enter((&vdp->xdf_cb_lk));
2025 		mutex_enter((&vdp->xdf_dev_lk));
2026 		if (rv == 0)
2027 			goto out;
2028 	}
2029 
2030 out:
2031 	ASSERT(MUTEX_HELD(&vdp->xdf_cb_lk));
2032 	ASSERT(MUTEX_HELD(&vdp->xdf_dev_lk));
2033 
2034 	if (vdp->xdf_connect_thread == curthread) {
2035 		/*
2036 		 * wake up someone else so they can become the connection
2037 		 * thread.
2038 		 */
2039 		cv_signal(&vdp->xdf_dev_cv);
2040 		vdp->xdf_connect_thread = NULL;
2041 	}
2042 
2043 	/* Try to lock the media */
2044 	mutex_exit((&vdp->xdf_dev_lk));
2045 	(void) xdf_media_req(vdp, XBV_MEDIA_REQ_LOCK, B_TRUE);
2046 	mutex_enter((&vdp->xdf_dev_lk));
2047 
2048 	vdp->xdf_connect_req--;
2049 	return (vdp->xdf_state);
2050 }
2051 
2052 static uint_t
2053 xdf_iorestart(caddr_t arg)
2054 {
2055 	xdf_t *vdp = (xdf_t *)arg;
2056 
2057 	ASSERT(vdp != NULL);
2058 
2059 	mutex_enter(&vdp->xdf_dev_lk);
2060 	ASSERT(ISDMACBON(vdp));
2061 	SETDMACBOFF(vdp);
2062 	mutex_exit(&vdp->xdf_dev_lk);
2063 
2064 	xdf_io_start(vdp);
2065 
2066 	return (DDI_INTR_CLAIMED);
2067 }
2068 
2069 #if defined(XPV_HVM_DRIVER)
2070 
2071 typedef struct xdf_hvm_entry {
2072 	list_node_t	xdf_he_list;
2073 	char		*xdf_he_path;
2074 	dev_info_t	*xdf_he_dip;
2075 } xdf_hvm_entry_t;
2076 
2077 static list_t xdf_hvm_list;
2078 static kmutex_t xdf_hvm_list_lock;
2079 
2080 static xdf_hvm_entry_t *
2081 i_xdf_hvm_find(const char *path, dev_info_t *dip)
2082 {
2083 	xdf_hvm_entry_t	*i;
2084 
2085 	ASSERT((path != NULL) || (dip != NULL));
2086 	ASSERT(MUTEX_HELD(&xdf_hvm_list_lock));
2087 
2088 	i = list_head(&xdf_hvm_list);
2089 	while (i != NULL) {
2090 		if ((path != NULL) && strcmp(i->xdf_he_path, path) != 0) {
2091 			i = list_next(&xdf_hvm_list, i);
2092 			continue;
2093 		}
2094 		if ((dip != NULL) && (i->xdf_he_dip != dip)) {
2095 			i = list_next(&xdf_hvm_list, i);
2096 			continue;
2097 		}
2098 		break;
2099 	}
2100 	return (i);
2101 }
2102 
2103 dev_info_t *
2104 xdf_hvm_hold(const char *path)
2105 {
2106 	xdf_hvm_entry_t	*i;
2107 	dev_info_t	*dip;
2108 
2109 	mutex_enter(&xdf_hvm_list_lock);
2110 	i = i_xdf_hvm_find(path, NULL);
2111 	if (i == NULL) {
2112 		mutex_exit(&xdf_hvm_list_lock);
2113 		return (B_FALSE);
2114 	}
2115 	ndi_hold_devi(dip = i->xdf_he_dip);
2116 	mutex_exit(&xdf_hvm_list_lock);
2117 	return (dip);
2118 }
2119 
2120 static void
2121 xdf_hvm_add(dev_info_t *dip)
2122 {
2123 	xdf_hvm_entry_t	*i;
2124 	char		*path;
2125 
2126 	/* figure out the path for the dip */
2127 	path = kmem_zalloc(MAXPATHLEN, KM_SLEEP);
2128 	(void) ddi_pathname(dip, path);
2129 
2130 	i = kmem_alloc(sizeof (*i), KM_SLEEP);
2131 	i->xdf_he_dip = dip;
2132 	i->xdf_he_path = i_ddi_strdup(path, KM_SLEEP);
2133 
2134 	mutex_enter(&xdf_hvm_list_lock);
2135 	ASSERT(i_xdf_hvm_find(path, NULL) == NULL);
2136 	ASSERT(i_xdf_hvm_find(NULL, dip) == NULL);
2137 	list_insert_head(&xdf_hvm_list, i);
2138 	mutex_exit(&xdf_hvm_list_lock);
2139 
2140 	kmem_free(path, MAXPATHLEN);
2141 }
2142 
2143 static void
2144 xdf_hvm_rm(dev_info_t *dip)
2145 {
2146 	xdf_hvm_entry_t	*i;
2147 
2148 	mutex_enter(&xdf_hvm_list_lock);
2149 	VERIFY((i = i_xdf_hvm_find(NULL, dip)) != NULL);
2150 	list_remove(&xdf_hvm_list, i);
2151 	mutex_exit(&xdf_hvm_list_lock);
2152 
2153 	kmem_free(i->xdf_he_path, strlen(i->xdf_he_path) + 1);
2154 	kmem_free(i, sizeof (*i));
2155 }
2156 
2157 static void
2158 xdf_hvm_init(void)
2159 {
2160 	list_create(&xdf_hvm_list, sizeof (xdf_hvm_entry_t),
2161 	    offsetof(xdf_hvm_entry_t, xdf_he_list));
2162 	mutex_init(&xdf_hvm_list_lock, NULL, MUTEX_DEFAULT, NULL);
2163 }
2164 
2165 static void
2166 xdf_hvm_fini(void)
2167 {
2168 	ASSERT(list_head(&xdf_hvm_list) == NULL);
2169 	list_destroy(&xdf_hvm_list);
2170 	mutex_destroy(&xdf_hvm_list_lock);
2171 }
2172 
2173 boolean_t
2174 xdf_hvm_connect(dev_info_t *dip)
2175 {
2176 	xdf_t	*vdp = (xdf_t *)ddi_get_driver_private(dip);
2177 	char	*oename, *str;
2178 	int	rv;
2179 
2180 	mutex_enter(&vdp->xdf_cb_lk);
2181 
2182 	/*
2183 	 * Before try to establish a connection we need to wait for the
2184 	 * backend hotplug scripts to have run.  Once they are run the
2185 	 * "<oename>/hotplug-status" property will be set to "connected".
2186 	 */
2187 	for (;;) {
2188 		ASSERT(MUTEX_HELD(&vdp->xdf_cb_lk));
2189 
2190 		/*
2191 		 * Get the xenbus path to the backend device.  Note that
2192 		 * we can't cache this path (and we look it up on each pass
2193 		 * through this loop) because it could change during
2194 		 * suspend, resume, and migration operations.
2195 		 */
2196 		if ((oename = xvdi_get_oename(dip)) == NULL) {
2197 			mutex_exit(&vdp->xdf_cb_lk);
2198 			return (B_FALSE);
2199 		}
2200 
2201 		str = NULL;
2202 		if ((xenbus_read_str(oename, XBP_HP_STATUS, &str) == 0) &&
2203 		    (strcmp(str, XBV_HP_STATUS_CONN) == 0))
2204 			break;
2205 
2206 		if (str != NULL)
2207 			strfree(str);
2208 
2209 		/* wait for an update to "<oename>/hotplug-status" */
2210 		if (cv_wait_sig(&vdp->xdf_hp_status_cv, &vdp->xdf_cb_lk) == 0) {
2211 			/* we got interrupted by a signal */
2212 			mutex_exit(&vdp->xdf_cb_lk);
2213 			return (B_FALSE);
2214 		}
2215 	}
2216 
2217 	/* Good news.  The backend hotplug scripts have been run. */
2218 	ASSERT(MUTEX_HELD(&vdp->xdf_cb_lk));
2219 	ASSERT(strcmp(str, XBV_HP_STATUS_CONN) == 0);
2220 	strfree(str);
2221 
2222 	/*
2223 	 * If we're emulating a cd device and if the backend doesn't support
2224 	 * media request opreations, then we're not going to bother trying
2225 	 * to establish a connection for a couple reasons.  First off, media
2226 	 * requests support is required to support operations like eject and
2227 	 * media locking.  Second, other backend platforms like Linux don't
2228 	 * support hvm pv cdrom access.  They don't even have a backend pv
2229 	 * driver for cdrom device nodes, so we don't want to block forever
2230 	 * waiting for a connection to a backend driver that doesn't exist.
2231 	 */
2232 	if (XD_IS_CD(vdp) && !xenbus_exists(oename, XBP_MEDIA_REQ_SUP)) {
2233 		mutex_exit(&vdp->xdf_cb_lk);
2234 		return (B_FALSE);
2235 	}
2236 
2237 	mutex_enter(&vdp->xdf_dev_lk);
2238 	rv = xdf_connect_locked(vdp, B_TRUE);
2239 	mutex_exit(&vdp->xdf_dev_lk);
2240 	mutex_exit(&vdp->xdf_cb_lk);
2241 
2242 	return ((rv == XD_READY) ? B_TRUE : B_FALSE);
2243 }
2244 
2245 int
2246 xdf_hvm_setpgeom(dev_info_t *dip, cmlb_geom_t *geomp)
2247 {
2248 	xdf_t	*vdp = (xdf_t *)ddi_get_driver_private(dip);
2249 
2250 	/* sanity check the requested physical geometry */
2251 	mutex_enter(&vdp->xdf_dev_lk);
2252 	if ((geomp->g_secsize != XB_BSIZE) ||
2253 	    (geomp->g_capacity == 0)) {
2254 		mutex_exit(&vdp->xdf_dev_lk);
2255 		return (EINVAL);
2256 	}
2257 
2258 	/*
2259 	 * If we've already connected to the backend device then make sure
2260 	 * we're not defining a physical geometry larger than our backend
2261 	 * device.
2262 	 */
2263 	if ((vdp->xdf_xdev_nblocks != 0) &&
2264 	    (geomp->g_capacity > vdp->xdf_xdev_nblocks)) {
2265 		mutex_exit(&vdp->xdf_dev_lk);
2266 		return (EINVAL);
2267 	}
2268 
2269 	bzero(&vdp->xdf_pgeom, sizeof (vdp->xdf_pgeom));
2270 	vdp->xdf_pgeom.g_ncyl = geomp->g_ncyl;
2271 	vdp->xdf_pgeom.g_acyl = geomp->g_acyl;
2272 	vdp->xdf_pgeom.g_nhead = geomp->g_nhead;
2273 	vdp->xdf_pgeom.g_nsect = geomp->g_nsect;
2274 	vdp->xdf_pgeom.g_secsize = geomp->g_secsize;
2275 	vdp->xdf_pgeom.g_capacity = geomp->g_capacity;
2276 	vdp->xdf_pgeom.g_intrlv = geomp->g_intrlv;
2277 	vdp->xdf_pgeom.g_rpm = geomp->g_rpm;
2278 
2279 	vdp->xdf_pgeom_fixed = B_TRUE;
2280 	mutex_exit(&vdp->xdf_dev_lk);
2281 
2282 	/* force a re-validation */
2283 	cmlb_invalidate(vdp->xdf_vd_lbl, NULL);
2284 
2285 	return (0);
2286 }
2287 
2288 boolean_t
2289 xdf_is_cd(dev_info_t *dip)
2290 {
2291 	xdf_t		*vdp = (xdf_t *)ddi_get_driver_private(dip);
2292 	boolean_t	rv;
2293 
2294 	mutex_enter(&vdp->xdf_cb_lk);
2295 	rv = XD_IS_CD(vdp);
2296 	mutex_exit(&vdp->xdf_cb_lk);
2297 	return (rv);
2298 }
2299 
2300 boolean_t
2301 xdf_is_rm(dev_info_t *dip)
2302 {
2303 	xdf_t		*vdp = (xdf_t *)ddi_get_driver_private(dip);
2304 	boolean_t	rv;
2305 
2306 	mutex_enter(&vdp->xdf_cb_lk);
2307 	rv = XD_IS_RM(vdp);
2308 	mutex_exit(&vdp->xdf_cb_lk);
2309 	return (rv);
2310 }
2311 
2312 boolean_t
2313 xdf_media_req_supported(dev_info_t *dip)
2314 {
2315 	xdf_t		*vdp = (xdf_t *)ddi_get_driver_private(dip);
2316 	boolean_t	rv;
2317 
2318 	mutex_enter(&vdp->xdf_cb_lk);
2319 	rv = vdp->xdf_media_req_supported;
2320 	mutex_exit(&vdp->xdf_cb_lk);
2321 	return (rv);
2322 }
2323 
2324 #endif /* XPV_HVM_DRIVER */
2325 
2326 static int
2327 xdf_lb_getcap(dev_info_t *dip, diskaddr_t *capp)
2328 {
2329 	xdf_t *vdp;
2330 	vdp = ddi_get_soft_state(xdf_ssp, ddi_get_instance(dip));
2331 
2332 	if (vdp == NULL)
2333 		return (ENXIO);
2334 
2335 	mutex_enter(&vdp->xdf_dev_lk);
2336 	*capp = vdp->xdf_pgeom.g_capacity;
2337 	DPRINTF(LBL_DBG, ("xdf@%s:capacity %llu\n", vdp->xdf_addr, *capp));
2338 	mutex_exit(&vdp->xdf_dev_lk);
2339 	return (0);
2340 }
2341 
2342 static int
2343 xdf_lb_getpgeom(dev_info_t *dip, cmlb_geom_t *geomp)
2344 {
2345 	xdf_t *vdp;
2346 
2347 	if ((vdp = ddi_get_soft_state(xdf_ssp, ddi_get_instance(dip))) == NULL)
2348 		return (ENXIO);
2349 	*geomp = vdp->xdf_pgeom;
2350 	return (0);
2351 }
2352 
2353 /*
2354  * No real HBA, no geometry available from it
2355  */
2356 /*ARGSUSED*/
2357 static int
2358 xdf_lb_getvgeom(dev_info_t *dip, cmlb_geom_t *geomp)
2359 {
2360 	return (EINVAL);
2361 }
2362 
2363 static int
2364 xdf_lb_getattribute(dev_info_t *dip, tg_attribute_t *tgattributep)
2365 {
2366 	xdf_t *vdp;
2367 
2368 	if (!(vdp = ddi_get_soft_state(xdf_ssp, ddi_get_instance(dip))))
2369 		return (ENXIO);
2370 
2371 	if (XD_IS_RO(vdp))
2372 		tgattributep->media_is_writable = 0;
2373 	else
2374 		tgattributep->media_is_writable = 1;
2375 	return (0);
2376 }
2377 
2378 /* ARGSUSED3 */
2379 int
2380 xdf_lb_getinfo(dev_info_t *dip, int cmd, void *arg, void *tg_cookie)
2381 {
2382 	int instance;
2383 	xdf_t   *vdp;
2384 
2385 	instance = ddi_get_instance(dip);
2386 
2387 	if ((vdp = ddi_get_soft_state(xdf_ssp, instance)) == NULL)
2388 		return (ENXIO);
2389 
2390 	switch (cmd) {
2391 	case TG_GETPHYGEOM:
2392 		return (xdf_lb_getpgeom(dip, (cmlb_geom_t *)arg));
2393 	case TG_GETVIRTGEOM:
2394 		return (xdf_lb_getvgeom(dip, (cmlb_geom_t *)arg));
2395 	case TG_GETCAPACITY:
2396 		return (xdf_lb_getcap(dip, (diskaddr_t *)arg));
2397 	case TG_GETBLOCKSIZE:
2398 		mutex_enter(&vdp->xdf_cb_lk);
2399 		*(uint32_t *)arg = vdp->xdf_xdev_secsize;
2400 		mutex_exit(&vdp->xdf_cb_lk);
2401 		return (0);
2402 	case TG_GETATTR:
2403 		return (xdf_lb_getattribute(dip, (tg_attribute_t *)arg));
2404 	default:
2405 		return (ENOTTY);
2406 	}
2407 }
2408 
2409 /* ARGSUSED5 */
2410 int
2411 xdf_lb_rdwr(dev_info_t *dip, uchar_t cmd, void *bufp,
2412     diskaddr_t start, size_t reqlen, void *tg_cookie)
2413 {
2414 	xdf_t *vdp;
2415 	struct buf *bp;
2416 	int err = 0;
2417 
2418 	vdp = ddi_get_soft_state(xdf_ssp, ddi_get_instance(dip));
2419 
2420 	/* We don't allow IO from the oe_change callback thread */
2421 	ASSERT(curthread != vdp->xdf_oe_change_thread);
2422 
2423 	if ((start + ((reqlen / (vdp->xdf_xdev_secsize / DEV_BSIZE))
2424 	    >> DEV_BSHIFT)) > vdp->xdf_pgeom.g_capacity)
2425 		return (EINVAL);
2426 
2427 	bp = getrbuf(KM_SLEEP);
2428 	if (cmd == TG_READ)
2429 		bp->b_flags = B_BUSY | B_READ;
2430 	else
2431 		bp->b_flags = B_BUSY | B_WRITE;
2432 
2433 	bp->b_un.b_addr = bufp;
2434 	bp->b_bcount = reqlen;
2435 	bp->b_blkno = start * (vdp->xdf_xdev_secsize / DEV_BSIZE);
2436 	bp->b_edev = DDI_DEV_T_NONE; /* don't have dev_t */
2437 
2438 	mutex_enter(&vdp->xdf_dev_lk);
2439 	xdf_bp_push(vdp, bp);
2440 	mutex_exit(&vdp->xdf_dev_lk);
2441 	xdf_io_start(vdp);
2442 	if (curthread == vdp->xdf_ready_tq_thread)
2443 		(void) xdf_ring_drain(vdp);
2444 	err = biowait(bp);
2445 	ASSERT(bp->b_flags & B_DONE);
2446 	freerbuf(bp);
2447 	return (err);
2448 }
2449 
2450 /*
2451  * Lock the current media.  Set the media state to "lock".
2452  * (Media locks are only respected by the backend driver.)
2453  */
2454 static int
2455 xdf_ioctl_mlock(xdf_t *vdp)
2456 {
2457 	int rv;
2458 	mutex_enter(&vdp->xdf_cb_lk);
2459 	rv = xdf_media_req(vdp, XBV_MEDIA_REQ_LOCK, B_TRUE);
2460 	mutex_exit(&vdp->xdf_cb_lk);
2461 	return (rv);
2462 }
2463 
2464 /*
2465  * Release a media lock.  Set the media state to "none".
2466  */
2467 static int
2468 xdf_ioctl_munlock(xdf_t *vdp)
2469 {
2470 	int rv;
2471 	mutex_enter(&vdp->xdf_cb_lk);
2472 	rv = xdf_media_req(vdp, XBV_MEDIA_REQ_NONE, B_TRUE);
2473 	mutex_exit(&vdp->xdf_cb_lk);
2474 	return (rv);
2475 }
2476 
2477 /*
2478  * Eject the current media.  Ignores any media locks.  (Media locks
2479  * are only for benifit of the the backend.)
2480  */
2481 static int
2482 xdf_ioctl_eject(xdf_t *vdp)
2483 {
2484 	int rv;
2485 
2486 	mutex_enter(&vdp->xdf_cb_lk);
2487 	if ((rv = xdf_media_req(vdp, XBV_MEDIA_REQ_EJECT, B_FALSE)) != 0) {
2488 		mutex_exit(&vdp->xdf_cb_lk);
2489 		return (rv);
2490 	}
2491 
2492 	/*
2493 	 * We've set the media requests xenbus parameter to eject, so now
2494 	 * disconnect from the backend, wait for the backend to clear
2495 	 * the media requets xenbus paramter, and then we can reconnect
2496 	 * to the backend.
2497 	 */
2498 	(void) xdf_disconnect(vdp, XD_UNKNOWN, B_TRUE);
2499 	mutex_enter(&vdp->xdf_dev_lk);
2500 	if (xdf_connect_locked(vdp, B_TRUE) != XD_READY) {
2501 		mutex_exit(&vdp->xdf_dev_lk);
2502 		mutex_exit(&vdp->xdf_cb_lk);
2503 		return (EIO);
2504 	}
2505 	mutex_exit(&vdp->xdf_dev_lk);
2506 	mutex_exit(&vdp->xdf_cb_lk);
2507 	return (0);
2508 }
2509 
2510 /*
2511  * Watch for media state changes.  This can be an insertion of a device
2512  * (triggered by a 'xm block-configure' request in another domain) or
2513  * the ejection of a device (triggered by a local "eject" operation).
2514  * For a full description of the DKIOCSTATE ioctl behavior see dkio(7I).
2515  */
2516 static int
2517 xdf_dkstate(xdf_t *vdp, enum dkio_state mstate)
2518 {
2519 	enum dkio_state		prev_state;
2520 
2521 	mutex_enter(&vdp->xdf_cb_lk);
2522 	prev_state = vdp->xdf_mstate;
2523 
2524 	if (vdp->xdf_mstate == mstate) {
2525 		while (vdp->xdf_mstate == prev_state) {
2526 			if (cv_wait_sig(&vdp->xdf_mstate_cv,
2527 			    &vdp->xdf_cb_lk) == 0) {
2528 				mutex_exit(&vdp->xdf_cb_lk);
2529 				return (EINTR);
2530 			}
2531 		}
2532 	}
2533 
2534 	if ((prev_state != DKIO_INSERTED) &&
2535 	    (vdp->xdf_mstate == DKIO_INSERTED)) {
2536 		(void) xdf_media_req(vdp, XBV_MEDIA_REQ_LOCK, B_TRUE);
2537 		mutex_exit(&vdp->xdf_cb_lk);
2538 		return (0);
2539 	}
2540 
2541 	mutex_exit(&vdp->xdf_cb_lk);
2542 	return (0);
2543 }
2544 
2545 /*ARGSUSED*/
2546 static int
2547 xdf_ioctl(dev_t dev, int cmd, intptr_t arg, int mode, cred_t *credp,
2548     int *rvalp)
2549 {
2550 	minor_t		minor = getminor(dev);
2551 	int		part = XDF_PART(minor);
2552 	xdf_t		*vdp;
2553 	int		rv;
2554 
2555 	if (((vdp = ddi_get_soft_state(xdf_ssp, XDF_INST(minor))) == NULL) ||
2556 	    (!xdf_isopen(vdp, part)))
2557 		return (ENXIO);
2558 
2559 	DPRINTF(IOCTL_DBG, ("xdf@%s:ioctl: cmd %d (0x%x)\n",
2560 	    vdp->xdf_addr, cmd, cmd));
2561 
2562 	switch (cmd) {
2563 	default:
2564 		return (ENOTTY);
2565 	case DKIOCG_PHYGEOM:
2566 	case DKIOCG_VIRTGEOM:
2567 	case DKIOCGGEOM:
2568 	case DKIOCSGEOM:
2569 	case DKIOCGAPART:
2570 	case DKIOCSAPART:
2571 	case DKIOCGVTOC:
2572 	case DKIOCSVTOC:
2573 	case DKIOCPARTINFO:
2574 	case DKIOCGEXTVTOC:
2575 	case DKIOCSEXTVTOC:
2576 	case DKIOCEXTPARTINFO:
2577 	case DKIOCGMBOOT:
2578 	case DKIOCSMBOOT:
2579 	case DKIOCGETEFI:
2580 	case DKIOCSETEFI:
2581 	case DKIOCSETEXTPART:
2582 	case DKIOCPARTITION:
2583 		return (cmlb_ioctl(vdp->xdf_vd_lbl, dev, cmd, arg, mode, credp,
2584 		    rvalp, NULL));
2585 	case FDEJECT:
2586 	case DKIOCEJECT:
2587 	case CDROMEJECT:
2588 		return (xdf_ioctl_eject(vdp));
2589 	case DKIOCLOCK:
2590 		return (xdf_ioctl_mlock(vdp));
2591 	case DKIOCUNLOCK:
2592 		return (xdf_ioctl_munlock(vdp));
2593 	case CDROMREADOFFSET: {
2594 		int offset = 0;
2595 		if (!XD_IS_CD(vdp))
2596 			return (ENOTTY);
2597 		if (ddi_copyout(&offset, (void *)arg, sizeof (int), mode))
2598 			return (EFAULT);
2599 		return (0);
2600 	}
2601 	case DKIOCGMEDIAINFO: {
2602 		struct dk_minfo media_info;
2603 
2604 		media_info.dki_lbsize = vdp->xdf_xdev_secsize;
2605 		media_info.dki_capacity = vdp->xdf_pgeom.g_capacity;
2606 		if (XD_IS_CD(vdp))
2607 			media_info.dki_media_type = DK_CDROM;
2608 		else
2609 			media_info.dki_media_type = DK_FIXED_DISK;
2610 
2611 		if (ddi_copyout(&media_info, (void *)arg,
2612 		    sizeof (struct dk_minfo), mode))
2613 			return (EFAULT);
2614 		return (0);
2615 	}
2616 	case DKIOCINFO: {
2617 		struct dk_cinfo info;
2618 
2619 		/* controller information */
2620 		if (XD_IS_CD(vdp))
2621 			info.dki_ctype = DKC_CDROM;
2622 		else
2623 			info.dki_ctype = DKC_VBD;
2624 
2625 		info.dki_cnum = 0;
2626 		(void) strncpy((char *)(&info.dki_cname), "xdf", 8);
2627 
2628 		/* unit information */
2629 		info.dki_unit = ddi_get_instance(vdp->xdf_dip);
2630 		(void) strncpy((char *)(&info.dki_dname), "xdf", 8);
2631 		info.dki_flags = DKI_FMTVOL;
2632 		info.dki_partition = part;
2633 		info.dki_maxtransfer = maxphys / DEV_BSIZE;
2634 		info.dki_addr = 0;
2635 		info.dki_space = 0;
2636 		info.dki_prio = 0;
2637 		info.dki_vec = 0;
2638 
2639 		if (ddi_copyout(&info, (void *)arg, sizeof (info), mode))
2640 			return (EFAULT);
2641 		return (0);
2642 	}
2643 	case DKIOCSTATE: {
2644 		enum dkio_state mstate;
2645 
2646 		if (ddi_copyin((void *)arg, &mstate,
2647 		    sizeof (mstate), mode) != 0)
2648 			return (EFAULT);
2649 		if ((rv = xdf_dkstate(vdp, mstate)) != 0)
2650 			return (rv);
2651 		mstate = vdp->xdf_mstate;
2652 		if (ddi_copyout(&mstate, (void *)arg,
2653 		    sizeof (mstate), mode) != 0)
2654 			return (EFAULT);
2655 		return (0);
2656 	}
2657 	case DKIOCREMOVABLE: {
2658 		int i = BOOLEAN2VOID(XD_IS_RM(vdp));
2659 		if (ddi_copyout(&i, (caddr_t)arg, sizeof (i), mode))
2660 			return (EFAULT);
2661 		return (0);
2662 	}
2663 	case DKIOCGETWCE: {
2664 		int i = BOOLEAN2VOID(XD_IS_RM(vdp));
2665 		if (ddi_copyout(&i, (void *)arg, sizeof (i), mode))
2666 			return (EFAULT);
2667 		return (0);
2668 	}
2669 	case DKIOCSETWCE: {
2670 		int i;
2671 		if (ddi_copyin((void *)arg, &i, sizeof (i), mode))
2672 			return (EFAULT);
2673 		vdp->xdf_wce = VOID2BOOLEAN(i);
2674 		return (0);
2675 	}
2676 	case DKIOCFLUSHWRITECACHE: {
2677 		struct dk_callback *dkc = (struct dk_callback *)arg;
2678 
2679 		if (vdp->xdf_flush_supported) {
2680 			rv = xdf_lb_rdwr(vdp->xdf_dip, TG_WRITE,
2681 			    NULL, 0, 0, (void *)dev);
2682 		} else if (vdp->xdf_feature_barrier &&
2683 		    !xdf_barrier_flush_disable) {
2684 			rv = xdf_lb_rdwr(vdp->xdf_dip, TG_WRITE,
2685 			    vdp->xdf_cache_flush_block, xdf_flush_block,
2686 			    vdp->xdf_xdev_secsize, (void *)dev);
2687 		} else {
2688 			return (ENOTTY);
2689 		}
2690 		if ((mode & FKIOCTL) && (dkc != NULL) &&
2691 		    (dkc->dkc_callback != NULL)) {
2692 			(*dkc->dkc_callback)(dkc->dkc_cookie, rv);
2693 			/* need to return 0 after calling callback */
2694 			rv = 0;
2695 		}
2696 		return (rv);
2697 	}
2698 	}
2699 	/*NOTREACHED*/
2700 }
2701 
2702 static int
2703 xdf_strategy(struct buf *bp)
2704 {
2705 	xdf_t	*vdp;
2706 	minor_t minor;
2707 	diskaddr_t p_blkct, p_blkst;
2708 	daddr_t blkno;
2709 	ulong_t nblks;
2710 	int part;
2711 
2712 	minor = getminor(bp->b_edev);
2713 	part = XDF_PART(minor);
2714 	vdp = ddi_get_soft_state(xdf_ssp, XDF_INST(minor));
2715 
2716 	mutex_enter(&vdp->xdf_dev_lk);
2717 	if (!xdf_isopen(vdp, part)) {
2718 		mutex_exit(&vdp->xdf_dev_lk);
2719 		xdf_io_err(bp, ENXIO, 0);
2720 		return (0);
2721 	}
2722 
2723 	/* We don't allow IO from the oe_change callback thread */
2724 	ASSERT(curthread != vdp->xdf_oe_change_thread);
2725 
2726 	/* Check for writes to a read only device */
2727 	if (!IS_READ(bp) && XD_IS_RO(vdp)) {
2728 		mutex_exit(&vdp->xdf_dev_lk);
2729 		xdf_io_err(bp, EROFS, 0);
2730 		return (0);
2731 	}
2732 
2733 	/* Check if this I/O is accessing a partition or the entire disk */
2734 	if ((long)bp->b_private == XB_SLICE_NONE) {
2735 		/* This I/O is using an absolute offset */
2736 		p_blkct = vdp->xdf_xdev_nblocks;
2737 		p_blkst = 0;
2738 	} else {
2739 		/* This I/O is using a partition relative offset */
2740 		mutex_exit(&vdp->xdf_dev_lk);
2741 		if (cmlb_partinfo(vdp->xdf_vd_lbl, part, &p_blkct,
2742 		    &p_blkst, NULL, NULL, NULL)) {
2743 			xdf_io_err(bp, ENXIO, 0);
2744 			return (0);
2745 		}
2746 		mutex_enter(&vdp->xdf_dev_lk);
2747 	}
2748 
2749 	/*
2750 	 * Adjust the real blkno and bcount according to the underline
2751 	 * physical sector size.
2752 	 */
2753 	blkno = bp->b_blkno / (vdp->xdf_xdev_secsize / XB_BSIZE);
2754 
2755 	/* check for a starting block beyond the disk or partition limit */
2756 	if (blkno > p_blkct) {
2757 		DPRINTF(IO_DBG, ("xdf@%s: block %lld exceeds VBD size %"PRIu64,
2758 		    vdp->xdf_addr, (longlong_t)blkno, (uint64_t)p_blkct));
2759 		mutex_exit(&vdp->xdf_dev_lk);
2760 		xdf_io_err(bp, EINVAL, 0);
2761 		return (0);
2762 	}
2763 
2764 	/* Legacy: don't set error flag at this case */
2765 	if (blkno == p_blkct) {
2766 		mutex_exit(&vdp->xdf_dev_lk);
2767 		bp->b_resid = bp->b_bcount;
2768 		biodone(bp);
2769 		return (0);
2770 	}
2771 
2772 	/* sanitize the input buf */
2773 	bioerror(bp, 0);
2774 	bp->b_resid = 0;
2775 	bp->av_back = bp->av_forw = NULL;
2776 
2777 	/* Adjust for partial transfer, this will result in an error later */
2778 	if (vdp->xdf_xdev_secsize != 0 &&
2779 	    vdp->xdf_xdev_secsize != XB_BSIZE) {
2780 		nblks = bp->b_bcount / vdp->xdf_xdev_secsize;
2781 	} else {
2782 		nblks = bp->b_bcount >> XB_BSHIFT;
2783 	}
2784 
2785 	if ((blkno + nblks) > p_blkct) {
2786 		if (vdp->xdf_xdev_secsize != 0 &&
2787 		    vdp->xdf_xdev_secsize != XB_BSIZE) {
2788 			bp->b_resid =
2789 			    ((blkno + nblks) - p_blkct) *
2790 			    vdp->xdf_xdev_secsize;
2791 		} else {
2792 			bp->b_resid =
2793 			    ((blkno + nblks) - p_blkct) <<
2794 			    XB_BSHIFT;
2795 		}
2796 		bp->b_bcount -= bp->b_resid;
2797 	}
2798 
2799 	DPRINTF(IO_DBG, ("xdf@%s: strategy blk %lld len %lu\n",
2800 	    vdp->xdf_addr, (longlong_t)blkno, (ulong_t)bp->b_bcount));
2801 
2802 	/* Fix up the buf struct */
2803 	bp->b_flags |= B_BUSY;
2804 	bp->b_private = (void *)(uintptr_t)p_blkst;
2805 
2806 	xdf_bp_push(vdp, bp);
2807 	mutex_exit(&vdp->xdf_dev_lk);
2808 	xdf_io_start(vdp);
2809 	if (do_polled_io)
2810 		(void) xdf_ring_drain(vdp);
2811 	return (0);
2812 }
2813 
2814 /*ARGSUSED*/
2815 static int
2816 xdf_read(dev_t dev, struct uio *uiop, cred_t *credp)
2817 {
2818 	xdf_t	*vdp;
2819 	minor_t minor;
2820 	diskaddr_t p_blkcnt;
2821 	int part;
2822 
2823 	minor = getminor(dev);
2824 	if ((vdp = ddi_get_soft_state(xdf_ssp, XDF_INST(minor))) == NULL)
2825 		return (ENXIO);
2826 
2827 	DPRINTF(IO_DBG, ("xdf@%s: read offset 0x%"PRIx64"\n",
2828 	    vdp->xdf_addr, (int64_t)uiop->uio_offset));
2829 
2830 	part = XDF_PART(minor);
2831 	if (!xdf_isopen(vdp, part))
2832 		return (ENXIO);
2833 
2834 	if (cmlb_partinfo(vdp->xdf_vd_lbl, part, &p_blkcnt,
2835 	    NULL, NULL, NULL, NULL))
2836 		return (ENXIO);
2837 
2838 	if (uiop->uio_loffset >= XB_DTOB(p_blkcnt, vdp))
2839 		return (ENOSPC);
2840 
2841 	if (U_INVAL(uiop))
2842 		return (EINVAL);
2843 
2844 	return (physio(xdf_strategy, NULL, dev, B_READ, xdfmin, uiop));
2845 }
2846 
2847 /*ARGSUSED*/
2848 static int
2849 xdf_write(dev_t dev, struct uio *uiop, cred_t *credp)
2850 {
2851 	xdf_t *vdp;
2852 	minor_t minor;
2853 	diskaddr_t p_blkcnt;
2854 	int part;
2855 
2856 	minor = getminor(dev);
2857 	if ((vdp = ddi_get_soft_state(xdf_ssp, XDF_INST(minor))) == NULL)
2858 		return (ENXIO);
2859 
2860 	DPRINTF(IO_DBG, ("xdf@%s: write offset 0x%"PRIx64"\n",
2861 	    vdp->xdf_addr, (int64_t)uiop->uio_offset));
2862 
2863 	part = XDF_PART(minor);
2864 	if (!xdf_isopen(vdp, part))
2865 		return (ENXIO);
2866 
2867 	if (cmlb_partinfo(vdp->xdf_vd_lbl, part, &p_blkcnt,
2868 	    NULL, NULL, NULL, NULL))
2869 		return (ENXIO);
2870 
2871 	if (uiop->uio_loffset >= XB_DTOB(p_blkcnt, vdp))
2872 		return (ENOSPC);
2873 
2874 	if (U_INVAL(uiop))
2875 		return (EINVAL);
2876 
2877 	return (physio(xdf_strategy, NULL, dev, B_WRITE, xdfmin, uiop));
2878 }
2879 
2880 /*ARGSUSED*/
2881 static int
2882 xdf_aread(dev_t dev, struct aio_req *aiop, cred_t *credp)
2883 {
2884 	xdf_t	*vdp;
2885 	minor_t minor;
2886 	struct uio *uiop = aiop->aio_uio;
2887 	diskaddr_t p_blkcnt;
2888 	int part;
2889 
2890 	minor = getminor(dev);
2891 	if ((vdp = ddi_get_soft_state(xdf_ssp, XDF_INST(minor))) == NULL)
2892 		return (ENXIO);
2893 
2894 	part = XDF_PART(minor);
2895 	if (!xdf_isopen(vdp, part))
2896 		return (ENXIO);
2897 
2898 	if (cmlb_partinfo(vdp->xdf_vd_lbl, part, &p_blkcnt,
2899 	    NULL, NULL, NULL, NULL))
2900 		return (ENXIO);
2901 
2902 	if (uiop->uio_loffset >= XB_DTOB(p_blkcnt, vdp))
2903 		return (ENOSPC);
2904 
2905 	if (U_INVAL(uiop))
2906 		return (EINVAL);
2907 
2908 	return (aphysio(xdf_strategy, anocancel, dev, B_READ, xdfmin, aiop));
2909 }
2910 
2911 /*ARGSUSED*/
2912 static int
2913 xdf_awrite(dev_t dev, struct aio_req *aiop, cred_t *credp)
2914 {
2915 	xdf_t *vdp;
2916 	minor_t minor;
2917 	struct uio *uiop = aiop->aio_uio;
2918 	diskaddr_t p_blkcnt;
2919 	int part;
2920 
2921 	minor = getminor(dev);
2922 	if ((vdp = ddi_get_soft_state(xdf_ssp, XDF_INST(minor))) == NULL)
2923 		return (ENXIO);
2924 
2925 	part = XDF_PART(minor);
2926 	if (!xdf_isopen(vdp, part))
2927 		return (ENXIO);
2928 
2929 	if (cmlb_partinfo(vdp->xdf_vd_lbl, part, &p_blkcnt,
2930 	    NULL, NULL, NULL, NULL))
2931 		return (ENXIO);
2932 
2933 	if (uiop->uio_loffset >= XB_DTOB(p_blkcnt, vdp))
2934 		return (ENOSPC);
2935 
2936 	if (U_INVAL(uiop))
2937 		return (EINVAL);
2938 
2939 	return (aphysio(xdf_strategy, anocancel, dev, B_WRITE, xdfmin, aiop));
2940 }
2941 
2942 static int
2943 xdf_dump(dev_t dev, caddr_t addr, daddr_t blkno, int nblk)
2944 {
2945 	struct buf dumpbuf, *dbp = &dumpbuf;
2946 	xdf_t	*vdp;
2947 	minor_t minor;
2948 	int err = 0;
2949 	int part;
2950 	diskaddr_t p_blkcnt, p_blkst;
2951 
2952 	minor = getminor(dev);
2953 	if ((vdp = ddi_get_soft_state(xdf_ssp, XDF_INST(minor))) == NULL)
2954 		return (ENXIO);
2955 
2956 	DPRINTF(IO_DBG, ("xdf@%s: dump addr (0x%p) blk (%ld) nblks (%d)\n",
2957 	    vdp->xdf_addr, (void *)addr, blkno, nblk));
2958 
2959 	/* We don't allow IO from the oe_change callback thread */
2960 	ASSERT(curthread != vdp->xdf_oe_change_thread);
2961 
2962 	part = XDF_PART(minor);
2963 	if (!xdf_isopen(vdp, part))
2964 		return (ENXIO);
2965 
2966 	if (cmlb_partinfo(vdp->xdf_vd_lbl, part, &p_blkcnt, &p_blkst,
2967 	    NULL, NULL, NULL))
2968 		return (ENXIO);
2969 
2970 	if ((blkno + nblk) >
2971 	    (p_blkcnt * (vdp->xdf_xdev_secsize / XB_BSIZE))) {
2972 		cmn_err(CE_WARN, "xdf@%s: block %ld exceeds VBD size %"PRIu64,
2973 		    vdp->xdf_addr, (daddr_t)((blkno + nblk) /
2974 		    (vdp->xdf_xdev_secsize / XB_BSIZE)), (uint64_t)p_blkcnt);
2975 		return (EINVAL);
2976 	}
2977 
2978 	bioinit(dbp);
2979 	dbp->b_flags = B_BUSY;
2980 	dbp->b_un.b_addr = addr;
2981 	dbp->b_bcount = nblk << DEV_BSHIFT;
2982 	dbp->b_blkno = blkno;
2983 	dbp->b_edev = dev;
2984 	dbp->b_private = (void *)(uintptr_t)p_blkst;
2985 
2986 	mutex_enter(&vdp->xdf_dev_lk);
2987 	xdf_bp_push(vdp, dbp);
2988 	mutex_exit(&vdp->xdf_dev_lk);
2989 	xdf_io_start(vdp);
2990 	err = xdf_ring_drain(vdp);
2991 	biofini(dbp);
2992 	return (err);
2993 }
2994 
2995 /*ARGSUSED*/
2996 static int
2997 xdf_close(dev_t dev, int flag, int otyp, struct cred *credp)
2998 {
2999 	minor_t	minor;
3000 	xdf_t	*vdp;
3001 	int part;
3002 	ulong_t parbit;
3003 
3004 	minor = getminor(dev);
3005 	if ((vdp = ddi_get_soft_state(xdf_ssp, XDF_INST(minor))) == NULL)
3006 		return (ENXIO);
3007 
3008 	mutex_enter(&vdp->xdf_dev_lk);
3009 	part = XDF_PART(minor);
3010 	if (!xdf_isopen(vdp, part)) {
3011 		mutex_exit(&vdp->xdf_dev_lk);
3012 		return (ENXIO);
3013 	}
3014 	parbit = 1 << part;
3015 
3016 	ASSERT((vdp->xdf_vd_open[otyp] & parbit) != 0);
3017 	if (otyp == OTYP_LYR) {
3018 		ASSERT(vdp->xdf_vd_lyropen[part] > 0);
3019 		if (--vdp->xdf_vd_lyropen[part] == 0)
3020 			vdp->xdf_vd_open[otyp] &= ~parbit;
3021 	} else {
3022 		vdp->xdf_vd_open[otyp] &= ~parbit;
3023 	}
3024 	vdp->xdf_vd_exclopen &= ~parbit;
3025 
3026 	mutex_exit(&vdp->xdf_dev_lk);
3027 	return (0);
3028 }
3029 
3030 static int
3031 xdf_open(dev_t *devp, int flag, int otyp, cred_t *credp)
3032 {
3033 	minor_t	minor;
3034 	xdf_t	*vdp;
3035 	int part;
3036 	ulong_t parbit;
3037 	diskaddr_t p_blkct = 0;
3038 	boolean_t firstopen;
3039 	boolean_t nodelay;
3040 
3041 	minor = getminor(*devp);
3042 	if ((vdp = ddi_get_soft_state(xdf_ssp, XDF_INST(minor))) == NULL)
3043 		return (ENXIO);
3044 
3045 	nodelay = (flag & (FNDELAY | FNONBLOCK));
3046 
3047 	DPRINTF(DDI_DBG, ("xdf@%s: opening\n", vdp->xdf_addr));
3048 
3049 	/* do cv_wait until connected or failed */
3050 	mutex_enter(&vdp->xdf_cb_lk);
3051 	mutex_enter(&vdp->xdf_dev_lk);
3052 	if (!nodelay && (xdf_connect_locked(vdp, B_TRUE) != XD_READY)) {
3053 		mutex_exit(&vdp->xdf_dev_lk);
3054 		mutex_exit(&vdp->xdf_cb_lk);
3055 		return (ENXIO);
3056 	}
3057 	mutex_exit(&vdp->xdf_cb_lk);
3058 
3059 	if ((flag & FWRITE) && XD_IS_RO(vdp)) {
3060 		mutex_exit(&vdp->xdf_dev_lk);
3061 		return (EROFS);
3062 	}
3063 
3064 	part = XDF_PART(minor);
3065 	parbit = 1 << part;
3066 	if ((vdp->xdf_vd_exclopen & parbit) ||
3067 	    ((flag & FEXCL) && xdf_isopen(vdp, part))) {
3068 		mutex_exit(&vdp->xdf_dev_lk);
3069 		return (EBUSY);
3070 	}
3071 
3072 	/* are we the first one to open this node? */
3073 	firstopen = !xdf_isopen(vdp, -1);
3074 
3075 	if (otyp == OTYP_LYR)
3076 		vdp->xdf_vd_lyropen[part]++;
3077 
3078 	vdp->xdf_vd_open[otyp] |= parbit;
3079 
3080 	if (flag & FEXCL)
3081 		vdp->xdf_vd_exclopen |= parbit;
3082 
3083 	mutex_exit(&vdp->xdf_dev_lk);
3084 
3085 	/* force a re-validation */
3086 	if (firstopen)
3087 		cmlb_invalidate(vdp->xdf_vd_lbl, NULL);
3088 
3089 	/* If this is a non-blocking open then we're done */
3090 	if (nodelay)
3091 		return (0);
3092 
3093 	/*
3094 	 * This is a blocking open, so we require:
3095 	 * - that the disk have a valid label on it
3096 	 * - that the size of the partition that we're opening is non-zero
3097 	 */
3098 	if ((cmlb_partinfo(vdp->xdf_vd_lbl, part, &p_blkct,
3099 	    NULL, NULL, NULL, NULL) != 0) || (p_blkct == 0)) {
3100 		(void) xdf_close(*devp, flag, otyp, credp);
3101 		return (ENXIO);
3102 	}
3103 
3104 	return (0);
3105 }
3106 
3107 /*ARGSUSED*/
3108 static void
3109 xdf_watch_hp_status_cb(dev_info_t *dip, const char *path, void *arg)
3110 {
3111 	xdf_t *vdp = (xdf_t *)ddi_get_driver_private(dip);
3112 	cv_broadcast(&vdp->xdf_hp_status_cv);
3113 }
3114 
3115 static int
3116 xdf_prop_op(dev_t dev, dev_info_t *dip, ddi_prop_op_t prop_op, int flags,
3117 	char *name, caddr_t valuep, int *lengthp)
3118 {
3119 	xdf_t	*vdp = ddi_get_soft_state(xdf_ssp, ddi_get_instance(dip));
3120 
3121 	/*
3122 	 * Sanity check that if a dev_t or dip were specified that they
3123 	 * correspond to this device driver.  On debug kernels we'll
3124 	 * panic and on non-debug kernels we'll return failure.
3125 	 */
3126 	ASSERT(ddi_driver_major(dip) == xdf_major);
3127 	ASSERT((dev == DDI_DEV_T_ANY) || (getmajor(dev) == xdf_major));
3128 	if ((ddi_driver_major(dip) != xdf_major) ||
3129 	    ((dev != DDI_DEV_T_ANY) && (getmajor(dev) != xdf_major)))
3130 		return (DDI_PROP_NOT_FOUND);
3131 
3132 	if (vdp == NULL)
3133 		return (ddi_prop_op(dev, dip, prop_op, flags,
3134 		    name, valuep, lengthp));
3135 
3136 	return (cmlb_prop_op(vdp->xdf_vd_lbl,
3137 	    dev, dip, prop_op, flags, name, valuep, lengthp,
3138 	    XDF_PART(getminor(dev)), NULL));
3139 }
3140 
3141 /*ARGSUSED*/
3142 static int
3143 xdf_getinfo(dev_info_t *dip, ddi_info_cmd_t cmd, void *arg, void **rp)
3144 {
3145 	int	instance = XDF_INST(getminor((dev_t)arg));
3146 	xdf_t	*vbdp;
3147 
3148 	switch (cmd) {
3149 	case DDI_INFO_DEVT2DEVINFO:
3150 		if ((vbdp = ddi_get_soft_state(xdf_ssp, instance)) == NULL) {
3151 			*rp = NULL;
3152 			return (DDI_FAILURE);
3153 		}
3154 		*rp = vbdp->xdf_dip;
3155 		return (DDI_SUCCESS);
3156 
3157 	case DDI_INFO_DEVT2INSTANCE:
3158 		*rp = (void *)(uintptr_t)instance;
3159 		return (DDI_SUCCESS);
3160 
3161 	default:
3162 		return (DDI_FAILURE);
3163 	}
3164 }
3165 
3166 /*ARGSUSED*/
3167 static int
3168 xdf_resume(dev_info_t *dip)
3169 {
3170 	xdf_t	*vdp;
3171 	char	*oename;
3172 
3173 	if ((vdp = ddi_get_soft_state(xdf_ssp, ddi_get_instance(dip))) == NULL)
3174 		goto err;
3175 
3176 	if (xdf_debug & SUSRES_DBG)
3177 		xen_printf("xdf@%s: xdf_resume\n", vdp->xdf_addr);
3178 
3179 	mutex_enter(&vdp->xdf_cb_lk);
3180 
3181 	if (xvdi_resume(dip) != DDI_SUCCESS) {
3182 		mutex_exit(&vdp->xdf_cb_lk);
3183 		goto err;
3184 	}
3185 
3186 	if (((oename = xvdi_get_oename(dip)) == NULL) ||
3187 	    (xvdi_add_xb_watch_handler(dip, oename, XBP_HP_STATUS,
3188 	    xdf_watch_hp_status_cb, NULL) != DDI_SUCCESS)) {
3189 		mutex_exit(&vdp->xdf_cb_lk);
3190 		goto err;
3191 	}
3192 
3193 	mutex_enter(&vdp->xdf_dev_lk);
3194 	ASSERT(vdp->xdf_state != XD_READY);
3195 	xdf_set_state(vdp, XD_UNKNOWN);
3196 	mutex_exit(&vdp->xdf_dev_lk);
3197 
3198 	if (xdf_setstate_init(vdp) != DDI_SUCCESS) {
3199 		mutex_exit(&vdp->xdf_cb_lk);
3200 		goto err;
3201 	}
3202 
3203 	mutex_exit(&vdp->xdf_cb_lk);
3204 
3205 	if (xdf_debug & SUSRES_DBG)
3206 		xen_printf("xdf@%s: xdf_resume: done\n", vdp->xdf_addr);
3207 	return (DDI_SUCCESS);
3208 err:
3209 	if (xdf_debug & SUSRES_DBG)
3210 		xen_printf("xdf@%s: xdf_resume: fail\n", vdp->xdf_addr);
3211 	return (DDI_FAILURE);
3212 }
3213 
3214 static int
3215 xdf_attach(dev_info_t *dip, ddi_attach_cmd_t cmd)
3216 {
3217 	int			n, instance = ddi_get_instance(dip);
3218 	ddi_iblock_cookie_t	ibc, softibc;
3219 	boolean_t		dev_iscd = B_FALSE;
3220 	xdf_t			*vdp;
3221 	char			*oename, *xsname, *str;
3222 
3223 	if ((n = ddi_prop_get_int(DDI_DEV_T_ANY, dip, DDI_PROP_NOTPROM,
3224 	    "xdf_debug", 0)) != 0)
3225 		xdf_debug = n;
3226 
3227 	switch (cmd) {
3228 	case DDI_RESUME:
3229 		return (xdf_resume(dip));
3230 	case DDI_ATTACH:
3231 		break;
3232 	default:
3233 		return (DDI_FAILURE);
3234 	}
3235 	/* DDI_ATTACH */
3236 
3237 	if (((xsname = xvdi_get_xsname(dip)) == NULL) ||
3238 	    ((oename = xvdi_get_oename(dip)) == NULL))
3239 		return (DDI_FAILURE);
3240 
3241 	/*
3242 	 * Disable auto-detach.  This is necessary so that we don't get
3243 	 * detached while we're disconnected from the back end.
3244 	 */
3245 	if ((ddi_prop_update_int(DDI_DEV_T_NONE, dip,
3246 	    DDI_NO_AUTODETACH, 1) != DDI_PROP_SUCCESS))
3247 		return (DDI_FAILURE);
3248 
3249 	/* driver handles kernel-issued IOCTLs */
3250 	if (ddi_prop_create(DDI_DEV_T_NONE, dip,
3251 	    DDI_PROP_CANSLEEP, DDI_KERNEL_IOCTL, NULL, 0) != DDI_PROP_SUCCESS)
3252 		return (DDI_FAILURE);
3253 
3254 	if (ddi_get_iblock_cookie(dip, 0, &ibc) != DDI_SUCCESS)
3255 		return (DDI_FAILURE);
3256 
3257 	if (ddi_get_soft_iblock_cookie(dip,
3258 	    DDI_SOFTINT_LOW, &softibc) != DDI_SUCCESS)
3259 		return (DDI_FAILURE);
3260 
3261 	if (xenbus_read_str(xsname, XBP_DEV_TYPE, &str) != 0) {
3262 		cmn_err(CE_WARN, "xdf@%s: cannot read device-type",
3263 		    ddi_get_name_addr(dip));
3264 		return (DDI_FAILURE);
3265 	}
3266 	if (strcmp(str, XBV_DEV_TYPE_CD) == 0)
3267 		dev_iscd = B_TRUE;
3268 	strfree(str);
3269 
3270 	if (ddi_soft_state_zalloc(xdf_ssp, instance) != DDI_SUCCESS)
3271 		return (DDI_FAILURE);
3272 
3273 	DPRINTF(DDI_DBG, ("xdf@%s: attaching\n", ddi_get_name_addr(dip)));
3274 	vdp = ddi_get_soft_state(xdf_ssp, instance);
3275 	ddi_set_driver_private(dip, vdp);
3276 	vdp->xdf_dip = dip;
3277 	vdp->xdf_addr = ddi_get_name_addr(dip);
3278 	vdp->xdf_suspending = B_FALSE;
3279 	vdp->xdf_media_req_supported = B_FALSE;
3280 	vdp->xdf_peer = INVALID_DOMID;
3281 	vdp->xdf_evtchn = INVALID_EVTCHN;
3282 	list_create(&vdp->xdf_vreq_act, sizeof (v_req_t),
3283 	    offsetof(v_req_t, v_link));
3284 	cv_init(&vdp->xdf_dev_cv, NULL, CV_DEFAULT, NULL);
3285 	cv_init(&vdp->xdf_hp_status_cv, NULL, CV_DEFAULT, NULL);
3286 	cv_init(&vdp->xdf_mstate_cv, NULL, CV_DEFAULT, NULL);
3287 	mutex_init(&vdp->xdf_dev_lk, NULL, MUTEX_DRIVER, (void *)ibc);
3288 	mutex_init(&vdp->xdf_cb_lk, NULL, MUTEX_DRIVER, (void *)ibc);
3289 	mutex_init(&vdp->xdf_iostat_lk, NULL, MUTEX_DRIVER, (void *)ibc);
3290 	vdp->xdf_cmbl_reattach = B_TRUE;
3291 	if (dev_iscd) {
3292 		vdp->xdf_dinfo |= VDISK_CDROM;
3293 		vdp->xdf_mstate = DKIO_EJECTED;
3294 	} else {
3295 		vdp->xdf_mstate = DKIO_NONE;
3296 	}
3297 
3298 	if ((vdp->xdf_ready_tq = ddi_taskq_create(dip, "xdf_ready_tq",
3299 	    1, TASKQ_DEFAULTPRI, 0)) == NULL)
3300 		goto errout0;
3301 
3302 	if (xvdi_add_xb_watch_handler(dip, oename, XBP_HP_STATUS,
3303 	    xdf_watch_hp_status_cb, NULL) != DDI_SUCCESS)
3304 		goto errout0;
3305 
3306 	if (ddi_add_softintr(dip, DDI_SOFTINT_LOW, &vdp->xdf_softintr_id,
3307 	    &softibc, NULL, xdf_iorestart, (caddr_t)vdp) != DDI_SUCCESS) {
3308 		cmn_err(CE_WARN, "xdf@%s: failed to add softintr",
3309 		    ddi_get_name_addr(dip));
3310 		goto errout0;
3311 	}
3312 
3313 	/*
3314 	 * Initialize the physical geometry stucture.  Note that currently
3315 	 * we don't know the size of the backend device so the number
3316 	 * of blocks on the device will be initialized to zero.  Once
3317 	 * we connect to the backend device we'll update the physical
3318 	 * geometry to reflect the real size of the device.
3319 	 */
3320 	xdf_synthetic_pgeom(dip, &vdp->xdf_pgeom);
3321 	vdp->xdf_pgeom_fixed = B_FALSE;
3322 
3323 	/*
3324 	 * create default device minor nodes: non-removable disk
3325 	 * we will adjust minor nodes after we are connected w/ backend
3326 	 */
3327 	cmlb_alloc_handle(&vdp->xdf_vd_lbl);
3328 	if (xdf_cmlb_attach(vdp) != 0) {
3329 		cmn_err(CE_WARN,
3330 		    "xdf@%s: attach failed, cmlb attach failed",
3331 		    ddi_get_name_addr(dip));
3332 		goto errout0;
3333 	}
3334 
3335 	/*
3336 	 * We ship with cache-enabled disks
3337 	 */
3338 	vdp->xdf_wce = B_TRUE;
3339 
3340 	mutex_enter(&vdp->xdf_cb_lk);
3341 	/* Watch backend XenbusState change */
3342 	if (xvdi_add_event_handler(dip,
3343 	    XS_OE_STATE, xdf_oe_change, NULL) != DDI_SUCCESS) {
3344 		mutex_exit(&vdp->xdf_cb_lk);
3345 		goto errout0;
3346 	}
3347 
3348 	if (xdf_setstate_init(vdp) != DDI_SUCCESS) {
3349 		cmn_err(CE_WARN, "xdf@%s: start connection failed",
3350 		    ddi_get_name_addr(dip));
3351 		mutex_exit(&vdp->xdf_cb_lk);
3352 		goto errout1;
3353 	}
3354 	mutex_exit(&vdp->xdf_cb_lk);
3355 
3356 #if defined(XPV_HVM_DRIVER)
3357 
3358 	xdf_hvm_add(dip);
3359 
3360 	/* Report our version to dom0.  */
3361 	if (xenbus_printf(XBT_NULL, "guest/xdf", "version", "%d",
3362 	    HVMPV_XDF_VERS))
3363 		cmn_err(CE_WARN, "xdf: couldn't write version\n");
3364 
3365 #else /* !XPV_HVM_DRIVER */
3366 
3367 	/* create kstat for iostat(1M) */
3368 	if (xdf_kstat_create(dip, "xdf", instance) != 0) {
3369 		cmn_err(CE_WARN, "xdf@%s: failed to create kstat",
3370 		    ddi_get_name_addr(dip));
3371 		goto errout1;
3372 	}
3373 
3374 #endif /* !XPV_HVM_DRIVER */
3375 
3376 	ddi_report_dev(dip);
3377 	DPRINTF(DDI_DBG, ("xdf@%s: attached\n", vdp->xdf_addr));
3378 	return (DDI_SUCCESS);
3379 
3380 errout1:
3381 	(void) xvdi_switch_state(vdp->xdf_dip, XBT_NULL, XenbusStateClosed);
3382 	xvdi_remove_event_handler(dip, XS_OE_STATE);
3383 errout0:
3384 	if (vdp->xdf_vd_lbl != NULL) {
3385 		cmlb_detach(vdp->xdf_vd_lbl, NULL);
3386 		cmlb_free_handle(&vdp->xdf_vd_lbl);
3387 		vdp->xdf_vd_lbl = NULL;
3388 	}
3389 	if (vdp->xdf_softintr_id != NULL)
3390 		ddi_remove_softintr(vdp->xdf_softintr_id);
3391 	xvdi_remove_xb_watch_handlers(dip);
3392 	if (vdp->xdf_ready_tq != NULL)
3393 		ddi_taskq_destroy(vdp->xdf_ready_tq);
3394 	mutex_destroy(&vdp->xdf_cb_lk);
3395 	mutex_destroy(&vdp->xdf_dev_lk);
3396 	cv_destroy(&vdp->xdf_dev_cv);
3397 	cv_destroy(&vdp->xdf_hp_status_cv);
3398 	ddi_soft_state_free(xdf_ssp, instance);
3399 	ddi_set_driver_private(dip, NULL);
3400 	ddi_prop_remove_all(dip);
3401 	cmn_err(CE_WARN, "xdf@%s: attach failed", ddi_get_name_addr(dip));
3402 	return (DDI_FAILURE);
3403 }
3404 
3405 static int
3406 xdf_suspend(dev_info_t *dip)
3407 {
3408 	int		instance = ddi_get_instance(dip);
3409 	xdf_t		*vdp;
3410 
3411 	if ((vdp = ddi_get_soft_state(xdf_ssp, instance)) == NULL)
3412 		return (DDI_FAILURE);
3413 
3414 	if (xdf_debug & SUSRES_DBG)
3415 		xen_printf("xdf@%s: xdf_suspend\n", vdp->xdf_addr);
3416 
3417 	xvdi_suspend(dip);
3418 
3419 	mutex_enter(&vdp->xdf_cb_lk);
3420 	mutex_enter(&vdp->xdf_dev_lk);
3421 
3422 	vdp->xdf_suspending = B_TRUE;
3423 	xdf_ring_destroy(vdp);
3424 	xdf_set_state(vdp, XD_SUSPEND);
3425 	vdp->xdf_suspending = B_FALSE;
3426 
3427 	mutex_exit(&vdp->xdf_dev_lk);
3428 	mutex_exit(&vdp->xdf_cb_lk);
3429 
3430 	if (xdf_debug & SUSRES_DBG)
3431 		xen_printf("xdf@%s: xdf_suspend: done\n", vdp->xdf_addr);
3432 
3433 	return (DDI_SUCCESS);
3434 }
3435 
3436 static int
3437 xdf_detach(dev_info_t *dip, ddi_detach_cmd_t cmd)
3438 {
3439 	xdf_t *vdp;
3440 	int instance;
3441 
3442 	switch (cmd) {
3443 
3444 	case DDI_PM_SUSPEND:
3445 		break;
3446 
3447 	case DDI_SUSPEND:
3448 		return (xdf_suspend(dip));
3449 
3450 	case DDI_DETACH:
3451 		break;
3452 
3453 	default:
3454 		return (DDI_FAILURE);
3455 	}
3456 
3457 	instance = ddi_get_instance(dip);
3458 	DPRINTF(DDI_DBG, ("xdf@%s: detaching\n", ddi_get_name_addr(dip)));
3459 	vdp = ddi_get_soft_state(xdf_ssp, instance);
3460 
3461 	if (vdp == NULL)
3462 		return (DDI_FAILURE);
3463 
3464 	mutex_enter(&vdp->xdf_cb_lk);
3465 	xdf_disconnect(vdp, XD_CLOSED, B_FALSE);
3466 	if (vdp->xdf_state != XD_CLOSED) {
3467 		mutex_exit(&vdp->xdf_cb_lk);
3468 		return (DDI_FAILURE);
3469 	}
3470 	mutex_exit(&vdp->xdf_cb_lk);
3471 
3472 	ASSERT(!ISDMACBON(vdp));
3473 
3474 #if defined(XPV_HVM_DRIVER)
3475 	xdf_hvm_rm(dip);
3476 #endif /* XPV_HVM_DRIVER */
3477 
3478 	if (vdp->xdf_timeout_id != 0)
3479 		(void) untimeout(vdp->xdf_timeout_id);
3480 
3481 	xvdi_remove_event_handler(dip, XS_OE_STATE);
3482 	ddi_taskq_destroy(vdp->xdf_ready_tq);
3483 
3484 	cmlb_detach(vdp->xdf_vd_lbl, NULL);
3485 	cmlb_free_handle(&vdp->xdf_vd_lbl);
3486 
3487 	/* we'll support backend running in domU later */
3488 #ifdef	DOMU_BACKEND
3489 	(void) xvdi_post_event(dip, XEN_HP_REMOVE);
3490 #endif
3491 
3492 	list_destroy(&vdp->xdf_vreq_act);
3493 	ddi_prop_remove_all(dip);
3494 	xdf_kstat_delete(dip);
3495 	ddi_remove_softintr(vdp->xdf_softintr_id);
3496 	xvdi_remove_xb_watch_handlers(dip);
3497 	ddi_set_driver_private(dip, NULL);
3498 	cv_destroy(&vdp->xdf_dev_cv);
3499 	mutex_destroy(&vdp->xdf_cb_lk);
3500 	mutex_destroy(&vdp->xdf_dev_lk);
3501 	if (vdp->xdf_cache_flush_block != NULL)
3502 		kmem_free(vdp->xdf_flush_mem, 2 * vdp->xdf_xdev_secsize);
3503 	ddi_soft_state_free(xdf_ssp, instance);
3504 	return (DDI_SUCCESS);
3505 }
3506 
3507 /*
3508  * Driver linkage structures.
3509  */
3510 static struct cb_ops xdf_cbops = {
3511 	xdf_open,
3512 	xdf_close,
3513 	xdf_strategy,
3514 	nodev,
3515 	xdf_dump,
3516 	xdf_read,
3517 	xdf_write,
3518 	xdf_ioctl,
3519 	nodev,
3520 	nodev,
3521 	nodev,
3522 	nochpoll,
3523 	xdf_prop_op,
3524 	NULL,
3525 	D_MP | D_NEW | D_64BIT,
3526 	CB_REV,
3527 	xdf_aread,
3528 	xdf_awrite
3529 };
3530 
3531 struct dev_ops xdf_devops = {
3532 	DEVO_REV,		/* devo_rev */
3533 	0,			/* devo_refcnt */
3534 	xdf_getinfo,		/* devo_getinfo */
3535 	nulldev,		/* devo_identify */
3536 	nulldev,		/* devo_probe */
3537 	xdf_attach,		/* devo_attach */
3538 	xdf_detach,		/* devo_detach */
3539 	nodev,			/* devo_reset */
3540 	&xdf_cbops,		/* devo_cb_ops */
3541 	NULL,			/* devo_bus_ops */
3542 	NULL,			/* devo_power */
3543 	ddi_quiesce_not_supported, /* devo_quiesce */
3544 };
3545 
3546 /*
3547  * Module linkage structures.
3548  */
3549 static struct modldrv modldrv = {
3550 	&mod_driverops,		/* Type of module.  This one is a driver */
3551 	"virtual block driver",	/* short description */
3552 	&xdf_devops		/* driver specific ops */
3553 };
3554 
3555 static struct modlinkage xdf_modlinkage = {
3556 	MODREV_1, (void *)&modldrv, NULL
3557 };
3558 
3559 /*
3560  * standard module entry points
3561  */
3562 int
3563 _init(void)
3564 {
3565 	int rc;
3566 
3567 	xdf_major = ddi_name_to_major("xdf");
3568 	if (xdf_major == (major_t)-1)
3569 		return (EINVAL);
3570 
3571 	if ((rc = ddi_soft_state_init(&xdf_ssp, sizeof (xdf_t), 0)) != 0)
3572 		return (rc);
3573 
3574 	xdf_vreq_cache = kmem_cache_create("xdf_vreq_cache",
3575 	    sizeof (v_req_t), 0, NULL, NULL, NULL, NULL, NULL, 0);
3576 	xdf_gs_cache = kmem_cache_create("xdf_gs_cache",
3577 	    sizeof (ge_slot_t), 0, NULL, NULL, NULL, NULL, NULL, 0);
3578 
3579 #if defined(XPV_HVM_DRIVER)
3580 	xdf_hvm_init();
3581 #endif /* XPV_HVM_DRIVER */
3582 
3583 	if ((rc = mod_install(&xdf_modlinkage)) != 0) {
3584 #if defined(XPV_HVM_DRIVER)
3585 		xdf_hvm_fini();
3586 #endif /* XPV_HVM_DRIVER */
3587 		kmem_cache_destroy(xdf_vreq_cache);
3588 		kmem_cache_destroy(xdf_gs_cache);
3589 		ddi_soft_state_fini(&xdf_ssp);
3590 		return (rc);
3591 	}
3592 
3593 	return (rc);
3594 }
3595 
3596 int
3597 _fini(void)
3598 {
3599 	int err;
3600 	if ((err = mod_remove(&xdf_modlinkage)) != 0)
3601 		return (err);
3602 
3603 #if defined(XPV_HVM_DRIVER)
3604 	xdf_hvm_fini();
3605 #endif /* XPV_HVM_DRIVER */
3606 
3607 	kmem_cache_destroy(xdf_vreq_cache);
3608 	kmem_cache_destroy(xdf_gs_cache);
3609 	ddi_soft_state_fini(&xdf_ssp);
3610 
3611 	return (0);
3612 }
3613 
3614 int
3615 _info(struct modinfo *modinfop)
3616 {
3617 	return (mod_info(&xdf_modlinkage, modinfop));
3618 }
3619