xref: /titanic_41/usr/src/uts/common/sys/mdi_impldefs.h (revision 159d09a20817016f09b3ea28d1bdada4a336bb91)
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  * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 #ifndef	_SYS_MDI_IMPLDEFS_H
27 #define	_SYS_MDI_IMPLDEFS_H
28 
29 
30 #include <sys/note.h>
31 #include <sys/types.h>
32 #include <sys/sunmdi.h>
33 #include <sys/modhash.h>
34 #include <sys/callb.h>
35 
36 #ifdef	__cplusplus
37 extern "C" {
38 #endif
39 
40 #ifdef _KERNEL
41 
42 /*
43  * Multipath Driver Interfaces
44  *
45  * The multipathing framework is provided in two modules.  The 'mpxio' misc.
46  * module provides the core multipath framework and the 'scsi_vhci' nexus
47  * driver provides the SCSI-III command set driver functionality for
48  * managing Fibre-Channel storage devices.
49  *
50  * As in any multipathing solution there are three major problems to solve:
51  *
52  * 1) Identification and enumeration of multipath client devices.
53  * 2) Optimal path selection when routing I/O requests.
54  * 3) Observability interfaces to snapshot the multipath configuration,
55  *    and infrastructure to provide performance and error statistics.
56  *
57  * The mpxio framework consists of several major components:
58  *
59  * 1) The MDI is the Multiplexed Device Interface; this is the core glue which
60  *    holds the following components together.
61  * 2) vHCI (Virtual Host Controller Interconnect) drivers provide multipathing
62  *    services for a given bus technology (example: 'scsi_vhci' provides
63  *    multipathing support for SCSI-III fibre-channel devices).
64  * 3) pHCI (Physical Host Controller Interconnect) drivers provide transport
65  *    services for a given host controller (example: 'fcp' provides transport
66  *    for fibre-channel devices).
67  * 4) Client Devices are standard Solaris target (or leaf) drivers
68  *    (example: 'ssd' is the standard disk driver for fibre-channel arrays).
69  * 5) Multipath information nodes ('pathinfo' nodes) connect client device
70  *    nodes and pHCI device nodes in the device tree.
71  *
72  * With the scsi_vhci, a QLC card, and mpxio enabled, the device tree might
73  * look like this:
74  *
75  *              /\
76  *             /  ............
77  *     <vHCI>:/               \
78  *      +-----------+   +-----------+
79  *      | scsi_vhci |   |  pci@1f,0 |
80  *      +-----------+   +-----------+
81  *            /   \               \
82  * <Client>: /     \ :<Client>     \ :parent(pHCI)
83  *  +----------+ +-----------+    +-------------+
84  *  | ssd 1    | | ssd 2     |    | qlc@0,0     |
85  *  +----------+ +-----------+    +-------------+
86  *   |            |                /        \
87  *   |            |       <pHCI>: /          \ :<pHCI>
88  *   |            |      +-------------+   +-------------+
89  *   |            |      | pHCI 1 (fp) |   | pHCI 2 (fp) |
90  *   |            |      +-------------+   +-------------+
91  *   |            |          /        |      /          |
92  *   |            |    +------+       |    +------+     |
93  *   |            |    | ssd 3|       |    | ssd  |     |
94  *   |            |    |!mpxio|       |    | (OBP)|     |
95  *   |            |    +------+       |    +------+     |
96  *   |            |                   |                 |
97  *   |            |       <pathinfo>: |                 |
98  *   |            |               +-------+         +--------+
99  *   |            +-------------->| path  |-------->| path   |
100  *   |                            | info  |         | info   |
101  *   |                            | node 1|         | node 3 |
102  *   |                            +-------+         +--------+
103  *   |                                |               |
104  *   |                                |            +~~~~~~~~+
105  *   |                            +-------+        :+--------+
106  *   +--------------------------->| path  |-------->| path   |
107  *                                | info  |        :| info   |
108  *                                | node 2|        +| node 4 |
109  *                                +-------+         +--------+
110  *
111  * The multipath information nodes (mdi_pathinfo nodes) establish the
112  * relationship between the pseudo client driver instance nodes (children
113  * of the vHCI) and the physical host controller interconnect (pHCI
114  * drivers) forming a matrix structure.
115  *
116  * The mpxio module implements locking at multiple granularity levels to
117  * support the needs of various consumers.  The multipath matrix can be
118  * column locked, or row locked depending on the consumer. The intention
119  * is to balance simplicity and performance.
120  *
121  * Locking:
122  *
123  * The devinfo locking still applies:
124  *
125  *   1) An ndi_devi_enter of a parent protects linkage/state of children.
126  *   2) state >= DS_INITIALIZED adds devi_ref of parent
127  *   3) devi_ref at state >= DS_ATTACHED prevents detach(9E).
128  *
129  * The ordering of 1) is (vHCI, pHCI). For a DEBUG kernel this ordering
130  * is asserted by the ndi_devi_enter() implementation.  There is also an
131  * ndi_devi_enter(Client), which is atypical since the client is a leaf.
132  * This is done to synchronize pathinfo nodes during devinfo snapshot (see
133  * di_register_pip) by pretending that the pathinfo nodes are children
134  * of the client.
135  *
136  * In addition to devinfo locking the current implementation utilizes
137  * the following locks:
138  *
139  *   mdi_mutex: protects the global list of vHCIs.
140  *
141  *   vh_phci_mutex: per-vHCI (mutex) lock: protects list of pHCIs registered
142  *   with vHCI.
143  *
144  *   vh_client_mutex: per-vHCI (mutex) lock: protects list/hash of Clients
145  *   associated with vHCI.
146  *
147  *   ph_mutex: per-pHCI (mutex) lock: protects the column (pHCI-mdi_pathinfo
148  *   node list) and per-pHCI structure fields.  mdi_pathinfo node creation,
149  *   deletion and child mdi_pathinfo node state changes are serialized on per
150  *   pHCI basis (Protection against DR).
151  *
152  *   ct_mutex: per-client (mutex) lock: protects the row (client-mdi_pathinfo
153  *   node list) and per-client structure fields.  The client-mdi_pathinfo node
154  *   list is typically walked to select an optimal path when routing I/O
155  *   requests.
156  *
157  *   pi_mutex: per-mdi_pathinfo (mutex) lock: protects the mdi_pathinfo node
158  *   structure fields.
159  *
160  * Note that per-Client structure and per-pHCI fields are freely readable when
161  * corresponding mdi_pathinfo locks are held, since holding an mdi_pathinfo
162  * node guarantees that its corresponding client and pHCI devices will not be
163  * freed.
164  */
165 
166 /*
167  * MDI Client global unique identifier property name string definition
168  */
169 extern const char			*mdi_client_guid_prop;
170 #define	MDI_CLIENT_GUID_PROP		(char *)mdi_client_guid_prop
171 
172 /*
173  * MDI Client load balancing policy definitions
174  *
175  * Load balancing policies are determined on a per-vHCI basis and are
176  * configurable via the vHCI's driver.conf file.
177  */
178 typedef enum {
179 	LOAD_BALANCE_NONE,		/* Alternate pathing		*/
180 	LOAD_BALANCE_RR,		/* Round Robin			*/
181 	LOAD_BALANCE_LBA		/* Logical Block Addressing	*/
182 } client_lb_t;
183 
184 typedef struct {
185 	int region_size;
186 }client_lb_args_t;
187 
188 /*
189  * MDI client load balancing property name/value string definitions
190  */
191 extern const char			*mdi_load_balance;
192 extern const char			*mdi_load_balance_none;
193 extern const char			*mdi_load_balance_ap;
194 extern const char			*mdi_load_balance_rr;
195 extern const char			*mdi_load_balance_lba;
196 
197 #define	LOAD_BALANCE_PROP		(char *)mdi_load_balance
198 #define	LOAD_BALANCE_PROP_NONE		(char *)mdi_load_balance_none
199 #define	LOAD_BALANCE_PROP_AP		(char *)mdi_load_balance_ap
200 #define	LOAD_BALANCE_PROP_RR		(char *)mdi_load_balance_rr
201 #define	LOAD_BALANCE_PROP_LBA		(char *)mdi_load_balance_lba
202 
203 /* default for region size */
204 #define	LOAD_BALANCE_DEFAULT_REGION_SIZE	18
205 
206 /*
207  * vHCI drivers:
208  *
209  * vHCI drivers are pseudo nexus drivers which implement multipath services
210  * for a specific command set or bus architecture ('class').  There is a
211  * single instance of the vHCI driver for each command set which supports
212  * multipath devices.
213  *
214  * Each vHCI driver registers the following callbacks from attach(9e).
215  */
216 #define	MDI_VHCI_OPS_REV_1		1
217 /*
218  * Change MDI_VHCI_OPS_REV_NAME as per MDI_VHCI_OPS_REV
219  */
220 #define	MDI_VHCI_OPS_REV	MDI_VHCI_OPS_REV_1
221 #define	MDI_VHCI_OPS_REV_NAME	"1"
222 
223 typedef struct mdi_vhci_ops {
224 	/* revision management */
225 	int	vo_revision;
226 
227 	/* mdi_pathinfo node init callback */
228 	int	(*vo_pi_init)(dev_info_t *vdip, mdi_pathinfo_t *pip, int flags);
229 
230 	/* mdi_pathinfo node uninit callback */
231 	int	(*vo_pi_uninit)(dev_info_t *vdip, mdi_pathinfo_t *pip,
232 		    int flags);
233 
234 	/* mdi_pathinfo node state change callback */
235 	int	(*vo_pi_state_change)(dev_info_t *vdip, mdi_pathinfo_t *pip,
236 		    mdi_pathinfo_state_t state, uint32_t, int flags);
237 
238 	/* Client path failover callback */
239 	int	(*vo_failover)(dev_info_t *vdip, dev_info_t *cdip, int flags);
240 
241 	/* Client attached callback */
242 	void	(*vo_client_attached)(dev_info_t *cdip);
243 } mdi_vhci_ops_t;
244 
245 /*
246  * An mdi_vhci structure is created and bound to the devinfo node of every
247  * registered vHCI class driver; this happens when a vHCI registers itself from
248  * attach(9e).  This structure is unbound and freed when the vHCI unregisters
249  * at detach(9e) time;
250  *
251  * Each vHCI driver is associated with a vHCI class name; this is the handle
252  * used to register and unregister pHCI drivers for a given transport.
253  *
254  * Locking: Different parts of this structure are guarded by different
255  * locks: global threading of multiple vHCIs and initialization is protected
256  * by mdi_mutex, the list of pHCIs associated with a vHCI is protected by
257  * vh_phci_mutex, and Clients are protected by vh_client_mutex.
258  *
259  * XXX Depending on the context, some of the fields can be freely read without
260  * holding any locks (ex. holding vh_client_mutex lock also guarantees that
261  * the vHCI (parent) cannot be unexpectedly freed).
262  */
263 typedef struct mdi_vhci {
264 	/* protected by mdi_mutex... */
265 	struct mdi_vhci		*vh_next;	/* next vHCI link	*/
266 	struct mdi_vhci		*vh_prev;	/* prev vHCI link	*/
267 	char			*vh_class;	/* vHCI class name	*/
268 	dev_info_t		*vh_dip;	/* vHCI devi handle	*/
269 	int			vh_refcnt;	/* vHCI reference count	*/
270 	struct mdi_vhci_config	*vh_config;	/* vHCI config		*/
271 	client_lb_t		vh_lb;		/* vHCI load-balancing	*/
272 	struct mdi_vhci_ops	*vh_ops;	/* vHCI callback vectors */
273 
274 	/* protected by MDI_VHCI_PHCI_LOCK vh_phci_mutex... */
275 	kmutex_t		vh_phci_mutex;	/* pHCI mutex		*/
276 	int			vh_phci_count;	/* pHCI device count	*/
277 	struct mdi_phci		*vh_phci_head;	/* pHCI list head	*/
278 	struct mdi_phci		*vh_phci_tail;	/* pHCI list tail	*/
279 
280 	/* protected by MDI_VHCI_CLIENT_LOCK vh_client_mutex... */
281 	kmutex_t		vh_client_mutex; /* Client mutex	*/
282 	int			vh_client_count; /* Client count	*/
283 	struct client_hash	*vh_client_table; /* Client hash	*/
284 } mdi_vhci_t;
285 
286 /*
287  * per-vHCI lock macros
288  */
289 #define	MDI_VHCI_PHCI_LOCK(vh)		mutex_enter(&(vh)->vh_phci_mutex)
290 #define	MDI_VHCI_PHCI_TRYLOCK(vh)	mutex_tryenter(&(vh)->vh_phci_mutex)
291 #define	MDI_VHCI_PHCI_UNLOCK(vh)	mutex_exit(&(vh)->vh_phci_mutex)
292 #ifdef	DEBUG
293 #define	MDI_VHCI_PCHI_LOCKED(vh)	MUTEX_HELD(&(vh)->vh_phci_mutex)
294 #endif	/* DEBUG */
295 #define	MDI_VHCI_CLIENT_LOCK(vh)	mutex_enter(&(vh)->vh_client_mutex)
296 #define	MDI_VHCI_CLIENT_TRYLOCK(vh)	mutex_tryenter(&(vh)->vh_client_mutex)
297 #define	MDI_VHCI_CLIENT_UNLOCK(vh)	mutex_exit(&(vh)->vh_client_mutex)
298 #ifdef	DEBUG
299 #define	MDI_VHCI_CLIENT_LOCKED(vh)	MUTEX_HELD(&(vh)->vh_client_mutex)
300 #endif	/* DEBUG */
301 
302 
303 /*
304  * GUID Hash definitions
305  *
306  * Since all the mpxio managed devices for a given class are enumerated under
307  * the single vHCI instance for that class, sequentially walking through the
308  * client device link to find a client would be prohibitively slow.
309  */
310 
311 #define	CLIENT_HASH_TABLE_SIZE	(32)	/* GUID hash */
312 
313 /*
314  * Client hash table structure
315  */
316 struct client_hash {
317 	struct mdi_client	*ct_hash_head;	/* Client hash head	*/
318 	int			ct_hash_count;	/* Client hash count	*/
319 };
320 
321 
322 /*
323  * pHCI Drivers:
324  *
325  * Physical HBA drivers provide transport services for mpxio-managed devices.
326  * As each pHCI instance is attached, it must register itself with the mpxio
327  * framework using mdi_phci_register().  When the pHCI is detached it must
328  * similarly call mdi_phci_unregister().
329  *
330  * The framework maintains a list of registered pHCI device instances for each
331  * vHCI.  This list involves (vh_phci_count, vh_phci_head, vh_phci_tail) and
332  * (ph_next, ph_prev, ph_vhci) and is protected by vh_phci_mutex.
333  *
334  * Locking order:
335  *
336  * _NOTE(LOCK_ORDER(mdi_mutex, mdi_phci::ph_mutex))		XXX
337  * _NOTE(LOCK_ORDER(mdi_phci::ph_mutex devinfo_tree_lock))		XXX
338  */
339 typedef struct mdi_phci {
340 	/* protected by MDI_VHCI_PHCI_LOCK vh_phci_mutex... */
341 	struct mdi_phci		*ph_next;	/* next pHCI link	*/
342 	struct mdi_phci		*ph_prev;	/* prev pHCI link	*/
343 	dev_info_t		*ph_dip;	/* pHCI devi handle	*/
344 	struct mdi_vhci 	*ph_vhci;	/* pHCI back ref. to vHCI */
345 
346 	/* protected by MDI_PHCI_LOCK ph_mutex... */
347 	kmutex_t		ph_mutex;	/* per-pHCI mutex	*/
348 	int			ph_path_count;	/* pi count		*/
349 	mdi_pathinfo_t		*ph_path_head;	/* pi list head		*/
350 	mdi_pathinfo_t		*ph_path_tail;	/* pi list tail		*/
351 	int			ph_flags;	/* pHCI operation flags	*/
352 	int			ph_unstable;	/* Paths in transient state */
353 	kcondvar_t		ph_unstable_cv;	/* Paths in transient state */
354 
355 	/* protected by mdi_phci_[gs]et_vhci_private caller... */
356 	void			*ph_vprivate;	/* vHCI driver private	*/
357 } mdi_phci_t;
358 
359 /*
360  * A pHCI device is 'unstable' while one or more paths are in a transitional
361  * state.  Hotplugging is prevented during this state.
362  */
363 #define	MDI_PHCI_UNSTABLE(ph)		(ph)->ph_unstable++;
364 #define	MDI_PHCI_STABLE(ph) { \
365 	(ph)->ph_unstable--; \
366 	if ((ph)->ph_unstable == 0) { \
367 		cv_broadcast(&(ph)->ph_unstable_cv); \
368 	} \
369 }
370 
371 /*
372  * per-pHCI lock macros
373  */
374 #define	MDI_PHCI_LOCK(ph)		mutex_enter(&(ph)->ph_mutex)
375 #define	MDI_PHCI_TRYLOCK(ph)		mutex_tryenter(&(ph)->ph_mutex)
376 #define	MDI_PHCI_UNLOCK(ph)		mutex_exit(&(ph)->ph_mutex)
377 #ifdef	DEBUG
378 #define	MDI_PHCI_LOCKED(vh)		MUTEX_HELD(&(ph)->ph_mutex)
379 #endif	/* DEBUG */
380 
381 /*
382  * pHCI state definitions and macros to track the pHCI driver instance state
383  */
384 #define	MDI_PHCI_FLAGS_OFFLINE		0x1	/* pHCI is offline */
385 #define	MDI_PHCI_FLAGS_SUSPEND		0x2	/* pHCI is suspended */
386 #define	MDI_PHCI_FLAGS_POWER_DOWN	0x4	/* pHCI is power down */
387 #define	MDI_PHCI_FLAGS_DETACH		0x8	/* pHCI is detached */
388 #define	MDI_PHCI_FLAGS_USER_DISABLE	0x10	/* pHCI is disabled,user */
389 #define	MDI_PHCI_FLAGS_D_DISABLE	0x20	/* pHCI is disabled,driver */
390 #define	MDI_PHCI_FLAGS_D_DISABLE_TRANS	0x40	/* pHCI is disabled,transient */
391 #define	MDI_PHCI_FLAGS_POWER_TRANSITION	0x80	/* pHCI is power transition */
392 
393 #define	MDI_PHCI_DISABLE_MASK						\
394 	    (MDI_PHCI_FLAGS_USER_DISABLE | MDI_PHCI_FLAGS_D_DISABLE |	\
395 	    MDI_PHCI_FLAGS_D_DISABLE_TRANS)
396 
397 #define	MDI_PHCI_IS_READY(ph)						\
398 	    (((ph)->ph_flags & MDI_PHCI_DISABLE_MASK) == 0)
399 
400 #define	MDI_PHCI_SET_OFFLINE(ph) 					{\
401 	    ASSERT(MDI_PHCI_LOCKED(ph));				\
402 	    (ph)->ph_flags |= MDI_PHCI_FLAGS_OFFLINE;			}
403 #define	MDI_PHCI_SET_ONLINE(ph)						{\
404 	    ASSERT(MDI_PHCI_LOCKED(ph));				\
405 	    (ph)->ph_flags &= ~MDI_PHCI_FLAGS_OFFLINE;			}
406 #define	MDI_PHCI_IS_OFFLINE(ph)						\
407 	    ((ph)->ph_flags & MDI_PHCI_FLAGS_OFFLINE)
408 
409 #define	MDI_PHCI_SET_SUSPEND(ph) 					{\
410 	    ASSERT(MDI_PHCI_LOCKED(ph));				\
411 	    (ph)->ph_flags |= MDI_PHCI_FLAGS_SUSPEND;			}
412 #define	MDI_PHCI_SET_RESUME(ph)						{\
413 	    ASSERT(MDI_PHCI_LOCKED(ph));				\
414 	    (ph)->ph_flags &= ~MDI_PHCI_FLAGS_SUSPEND;			}
415 #define	MDI_PHCI_IS_SUSPENDED(ph)					\
416 	    ((ph)->ph_flags & MDI_PHCI_FLAGS_SUSPEND)
417 
418 #define	MDI_PHCI_SET_DETACH(ph)						{\
419 	    ASSERT(MDI_PHCI_LOCKED(ph));				\
420 	    (ph)->ph_flags |= MDI_PHCI_FLAGS_DETACH;			}
421 #define	MDI_PHCI_SET_ATTACH(ph)						{\
422 	    ASSERT(MDI_PHCI_LOCKED(ph));				\
423 	    (ph)->ph_flags &= ~MDI_PHCI_FLAGS_DETACH;			}
424 
425 #define	MDI_PHCI_SET_POWER_DOWN(ph)					{\
426 	    ASSERT(MDI_PHCI_LOCKED(ph));				\
427 	    (ph)->ph_flags |= MDI_PHCI_FLAGS_POWER_DOWN;		}
428 #define	MDI_PHCI_SET_POWER_UP(ph)					{\
429 	    ASSERT(MDI_PHCI_LOCKED(ph));				\
430 	    (ph)->ph_flags &= ~MDI_PHCI_FLAGS_POWER_DOWN;		}
431 #define	MDI_PHCI_IS_POWERED_DOWN(ph)					\
432 	    ((ph)->ph_flags & MDI_PHCI_FLAGS_POWER_DOWN)
433 
434 #define	MDI_PHCI_SET_USER_ENABLE(ph)					{\
435 	    ASSERT(MDI_PHCI_LOCKED(ph));				\
436 	    (ph)->ph_flags &= ~MDI_PHCI_FLAGS_USER_DISABLE;		}
437 #define	MDI_PHCI_SET_USER_DISABLE(ph)					{\
438 	    ASSERT(MDI_PHCI_LOCKED(ph));				\
439 	    (ph)->ph_flags |= MDI_PHCI_FLAGS_USER_DISABLE;		}
440 #define	MDI_PHCI_IS_USER_DISABLED(ph)					\
441 	    ((ph)->ph_flags & MDI_PHCI_FLAGS_USER_DISABLE)
442 
443 #define	MDI_PHCI_SET_DRV_ENABLE(ph)					{\
444 	    ASSERT(MDI_PHCI_LOCKED(ph));				\
445 	    (ph)->ph_flags &= ~MDI_PHCI_FLAGS_D_DISABLE;		}
446 #define	MDI_PHCI_SET_DRV_DISABLE(ph)					{\
447 	    ASSERT(MDI_PHCI_LOCKED(ph));				\
448 	    (ph)->ph_flags |= MDI_PHCI_FLAGS_D_DISABLE;			}
449 #define	MDI_PHCI_IS_DRV_DISABLED(ph)					\
450 	    ((ph)->ph_flags & MDI_PHCI_FLAGS_D_DISABLE)
451 
452 #define	MDI_PHCI_SET_DRV_ENABLE_TRANSIENT(ph)				{\
453 	    ASSERT(MDI_PHCI_LOCKED(ph));				\
454 	    (ph)->ph_flags &= ~MDI_PHCI_FLAGS_D_DISABLE_TRANS;		}
455 #define	MDI_PHCI_SET_DRV_DISABLE_TRANSIENT(ph)				{\
456 	    ASSERT(MDI_PHCI_LOCKED(ph));				\
457 	    (ph)->ph_flags |= MDI_PHCI_FLAGS_D_DISABLE_TRANS;		}
458 #define	MDI_PHCI_IS_DRV_DISABLED_TRANSIENT(ph)				\
459 	    ((ph)->ph_flags & MDI_PHCI_FLAGS_D_DISABLE_TRANS)
460 
461 #define	MDI_PHCI_SET_POWER_TRANSITION(ph)				{\
462 	    ASSERT(MDI_PHCI_LOCKED(ph));				\
463 	    (ph)->ph_flags |= MDI_PHCI_FLAGS_POWER_TRANSITION;		}
464 #define	MDI_PHCI_CLEAR_POWER_TRANSITION(ph)				{\
465 	    ASSERT(MDI_PHCI_LOCKED(ph));				\
466 	    (ph)->ph_flags &= ~MDI_PHCI_FLAGS_POWER_TRANSITION;		}
467 #define	MDI_PHCI_IS_POWER_TRANSITION(ph)				\
468 	    ((ph)->ph_flags & MDI_PHCI_FLAGS_POWER_TRANSITION)
469 
470 /*
471  * mpxio Managed Clients:
472  *
473  * This framework creates a struct mdi_client for every client device created
474  * by the framework as a result of self-enumeration of target devices by the
475  * registered pHCI devices.  This structure is bound to client device dev_info
476  * node at the time of client device allocation (ndi_devi_alloc(9e)). This
477  * structure is unbound from the dev_info node when mpxio framework removes a
478  * client device node from the system.
479  *
480  * This structure is created when a first path is enumerated and removed when
481  * last path is de-enumerated from the system.
482  *
483  * Multipath client devices are instantiated as children of corresponding vHCI
484  * driver instance. Each client device is uniquely identified by a GUID
485  * provided by target device itself.  The parent vHCI device also maintains a
486  * hashed list of client devices, protected by vh_client_mutex.
487  *
488  * Typically pHCI devices self-enumerate their child devices using taskq,
489  * resulting in multiple paths to the same client device to be enumerated by
490  * competing threads.
491  *
492  * Currently this framework supports two kinds of load-balancing policy
493  * configurable through the vHCI driver configuration files.
494  *
495  * NONE		- Legacy AP mode
496  * Round Robin	- Balance the pHCI load in a Round Robin fashion.
497  *
498  * This framework identifies the client device in three distinct states:
499  *
500  * OPTIMAL	- Client device has atleast one redundant path.
501  * DEGRADED	- No redundant paths (critical).  Failure in the current active
502  *		  path would result in data access failures.
503  * FAILED 	- No paths are available to access this device.
504  *
505  * Locking order:
506  *
507  * _NOTE(LOCK_ORDER(mdi_mutex, mdi_client::ct_mutex))			XXX
508  * _NOTE(LOCK_ORDER(mdi_client::ct_mutex devinfo_tree_lock))		XXX
509  */
510 typedef struct mdi_client {
511 	/* protected by MDI_VHCI_CLIENT_LOCK vh_client_mutex... */
512 	struct mdi_client	*ct_hnext;	/* next client		*/
513 	struct mdi_client	*ct_hprev;	/* prev client		*/
514 	dev_info_t		*ct_dip;	/* client devi handle	*/
515 	struct mdi_vhci		*ct_vhci;	/* vHCI back ref	*/
516 	char			*ct_drvname;	/* client driver name	*/
517 	char			*ct_guid;	/* client guid		*/
518 	client_lb_t		ct_lb;		/* load balancing scheme */
519 	client_lb_args_t	*ct_lb_args; 	/* load balancing args */
520 
521 
522 	/* protected by MDI_CLIENT_LOCK ct_mutex... */
523 	kmutex_t		ct_mutex;	/* per-client mutex	*/
524 	int			ct_path_count;	/* multi path count	*/
525 	mdi_pathinfo_t		*ct_path_head;	/* multi path list head	*/
526 	mdi_pathinfo_t		*ct_path_tail;	/* multi path list tail	*/
527 	mdi_pathinfo_t		*ct_path_last;	/* last path used for i/o */
528 	int			ct_state;	/* state information	*/
529 	int			ct_flags;	/* Driver op. flags	*/
530 	int			ct_failover_flags;	/* Failover args */
531 	int			ct_failover_status;	/* last fo status */
532 	kcondvar_t		ct_failover_cv;	/* Failover status cv	*/
533 	int			ct_unstable;	/* Paths in transient state */
534 	kcondvar_t		ct_unstable_cv;	/* Paths in transient state */
535 
536 	int			ct_power_cnt;	/* Hold count on parent power */
537 	kcondvar_t		ct_powerchange_cv;
538 					/* Paths in power transient state */
539 	short			ct_powercnt_config;
540 					/* held in pre/post config */
541 	short			ct_powercnt_unconfig;
542 					/* held in pre/post unconfig */
543 	int			ct_powercnt_reset;
544 					/* ct_power_cnt was resetted */
545 
546 	void			*ct_cprivate;	/* client driver private */
547 	void			*ct_vprivate;	/* vHCI driver private	*/
548 } mdi_client_t;
549 
550 /*
551  * per-Client device locking definitions
552  */
553 #define	MDI_CLIENT_LOCK(ct)		mutex_enter(&(ct)->ct_mutex)
554 #define	MDI_CLIENT_TRYLOCK(ct)		mutex_tryenter(&(ct)->ct_mutex)
555 #define	MDI_CLIENT_UNLOCK(ct)		mutex_exit(&(ct)->ct_mutex)
556 #ifdef	DEBUG
557 #define	MDI_CLIENT_LOCKED(ct)		MUTEX_HELD(&(ct)->ct_mutex)
558 #endif	/* DEBUG */
559 
560 /*
561  * A Client device is in unstable while one or more paths are in transitional
562  * state.  We do not allow failover to take place while paths are in transient
563  * state. Similarly we do not allow state transition while client device
564  * failover is in progress.
565  */
566 #define	MDI_CLIENT_UNSTABLE(ct)		(ct)->ct_unstable++;
567 #define	MDI_CLIENT_STABLE(ct) { \
568 	(ct)->ct_unstable--; \
569 	if ((ct)->ct_unstable == 0) { \
570 		cv_broadcast(&(ct)->ct_unstable_cv); \
571 	} \
572 }
573 
574 /*
575  * Client driver instance state definitions:
576  */
577 #define	MDI_CLIENT_FLAGS_OFFLINE		0x00000001
578 #define	MDI_CLIENT_FLAGS_SUSPEND		0x00000002
579 #define	MDI_CLIENT_FLAGS_POWER_DOWN		0x00000004
580 #define	MDI_CLIENT_FLAGS_DETACH			0x00000008
581 #define	MDI_CLIENT_FLAGS_FAILOVER		0x00000010
582 #define	MDI_CLIENT_FLAGS_REPORT_DEV		0x00000020
583 #define	MDI_CLIENT_FLAGS_PATH_FREE_IN_PROGRESS	0x00000040
584 #define	MDI_CLIENT_FLAGS_ASYNC_FREE		0x00000080
585 #define	MDI_CLIENT_FLAGS_DEV_NOT_SUPPORTED	0x00000100
586 #define	MDI_CLIENT_FLAGS_POWER_TRANSITION	0x00000200
587 
588 #define	MDI_CLIENT_SET_OFFLINE(ct)					{\
589 	    ASSERT(MDI_CLIENT_LOCKED(ct));				\
590 	    (ct)->ct_flags |= MDI_CLIENT_FLAGS_OFFLINE;			}
591 #define	MDI_CLIENT_SET_ONLINE(ct)					{\
592 	    ASSERT(MDI_CLIENT_LOCKED(ct));				\
593 	    (ct)->ct_flags &= ~MDI_CLIENT_FLAGS_OFFLINE;		}
594 #define	MDI_CLIENT_IS_OFFLINE(ct) \
595 	    ((ct)->ct_flags & MDI_CLIENT_FLAGS_OFFLINE)
596 
597 #define	MDI_CLIENT_SET_SUSPEND(ct)					{\
598 	    ASSERT(MDI_CLIENT_LOCKED(ct));				\
599 	    (ct)->ct_flags |= MDI_CLIENT_FLAGS_SUSPEND;			}
600 #define	MDI_CLIENT_SET_RESUME(ct)					{\
601 	    ASSERT(MDI_CLIENT_LOCKED(ct));				\
602 	    (ct)->ct_flags &= ~MDI_CLIENT_FLAGS_SUSPEND;		}
603 #define	MDI_CLIENT_IS_SUSPENDED(ct) \
604 	    ((ct)->ct_flags & MDI_CLIENT_FLAGS_SUSPEND)
605 
606 #define	MDI_CLIENT_SET_POWER_DOWN(ct)					{\
607 	    ASSERT(MDI_CLIENT_LOCKED(ct));				\
608 	    (ct)->ct_flags |= MDI_CLIENT_FLAGS_POWER_DOWN;		}
609 #define	MDI_CLIENT_SET_POWER_UP(ct)					{\
610 	    ASSERT(MDI_CLIENT_LOCKED(ct));				\
611 	    (ct)->ct_flags &= ~MDI_CLIENT_FLAGS_POWER_DOWN;		}
612 #define	MDI_CLIENT_IS_POWERED_DOWN(ct) \
613 	    ((ct)->ct_flags & MDI_CLIENT_FLAGS_POWER_DOWN)
614 
615 #define	MDI_CLIENT_SET_POWER_TRANSITION(ct)				{\
616 	    ASSERT(MDI_CLIENT_LOCKED(ct));				\
617 	    (ct)->ct_flags |= MDI_CLIENT_FLAGS_POWER_TRANSITION;	}
618 #define	MDI_CLIENT_CLEAR_POWER_TRANSITION(ct)				{\
619 	    ASSERT(MDI_CLIENT_LOCKED(ct));				\
620 	    (ct)->ct_flags &= ~MDI_CLIENT_FLAGS_POWER_TRANSITION;	}
621 #define	MDI_CLIENT_IS_POWER_TRANSITION(ct) \
622 	    ((ct)->ct_flags & MDI_CLIENT_FLAGS_POWER_TRANSITION)
623 
624 #define	MDI_CLIENT_SET_DETACH(ct)					{\
625 	    ASSERT(MDI_CLIENT_LOCKED(ct));				\
626 	    (ct)->ct_flags |= MDI_CLIENT_FLAGS_DETACH;			}
627 #define	MDI_CLIENT_SET_ATTACH(ct)					{\
628 	    ASSERT(MDI_CLIENT_LOCKED(ct));				\
629 	    (ct)->ct_flags &= ~MDI_CLIENT_FLAGS_DETACH;			}
630 #define	MDI_CLIENT_IS_DETACHED(ct) \
631 	    ((ct)->ct_flags & MDI_CLIENT_FLAGS_DETACH)
632 
633 #define	MDI_CLIENT_SET_FAILOVER_IN_PROGRESS(ct)				{\
634 	    ASSERT(MDI_CLIENT_LOCKED(ct));				\
635 	    (ct)->ct_flags |= MDI_CLIENT_FLAGS_FAILOVER;		}
636 #define	MDI_CLIENT_CLEAR_FAILOVER_IN_PROGRESS(ct)			{\
637 	    ASSERT(MDI_CLIENT_LOCKED(ct));				\
638 	    (ct)->ct_flags &= ~MDI_CLIENT_FLAGS_FAILOVER;		}
639 #define	MDI_CLIENT_IS_FAILOVER_IN_PROGRESS(ct) \
640 	    ((ct)->ct_flags & MDI_CLIENT_FLAGS_FAILOVER)
641 
642 #define	MDI_CLIENT_SET_REPORT_DEV_NEEDED(ct)				{\
643 	    ASSERT(MDI_CLIENT_LOCKED(ct));				\
644 	    (ct)->ct_flags |= MDI_CLIENT_FLAGS_REPORT_DEV;		}
645 #define	MDI_CLIENT_CLEAR_REPORT_DEV_NEEDED(ct)				{\
646 	    ASSERT(MDI_CLIENT_LOCKED(ct));				\
647 	    (ct)->ct_flags &= ~MDI_CLIENT_FLAGS_REPORT_DEV;		}
648 #define	MDI_CLIENT_IS_REPORT_DEV_NEEDED(ct) \
649 	    ((ct)->ct_flags & MDI_CLIENT_FLAGS_REPORT_DEV)
650 
651 #define	MDI_CLIENT_SET_PATH_FREE_IN_PROGRESS(ct)			{\
652 	    ASSERT(MDI_CLIENT_LOCKED(ct));				\
653 	    (ct)->ct_flags |= MDI_CLIENT_FLAGS_PATH_FREE_IN_PROGRESS;	}
654 #define	MDI_CLIENT_CLEAR_PATH_FREE_IN_PROGRESS(ct)			{\
655 	    ASSERT(MDI_CLIENT_LOCKED(ct));				\
656 	    (ct)->ct_flags &= ~MDI_CLIENT_FLAGS_PATH_FREE_IN_PROGRESS;	}
657 #define	MDI_CLIENT_IS_PATH_FREE_IN_PROGRESS(ct) \
658 	    ((ct)->ct_flags & MDI_CLIENT_FLAGS_PATH_FREE_IN_PROGRESS)
659 
660 #define	MDI_CLIENT_SET_DEV_NOT_SUPPORTED(ct)				{\
661 	    ASSERT(MDI_CLIENT_LOCKED(ct));				\
662 	    (ct)->ct_flags |= MDI_CLIENT_FLAGS_DEV_NOT_SUPPORTED;	}
663 #define	MDI_CLIENT_IS_DEV_NOT_SUPPORTED(ct) \
664 	    ((ct)->ct_flags & MDI_CLIENT_FLAGS_DEV_NOT_SUPPORTED)
665 
666 /*
667  * Client operating states.
668  */
669 #define	MDI_CLIENT_STATE_OPTIMAL	1
670 #define	MDI_CLIENT_STATE_DEGRADED	2
671 #define	MDI_CLIENT_STATE_FAILED		3
672 
673 #define	MDI_CLIENT_STATE(ct) ((ct)->ct_state)
674 #define	MDI_CLIENT_SET_STATE(ct, state) ((ct)->ct_state = state)
675 
676 #define	MDI_CLIENT_IS_FAILED(ct) \
677 	    ((ct)->ct_state == MDI_CLIENT_STATE_FAILED)
678 
679 /*
680  * mdi_pathinfo nodes:
681  *
682  * From this framework's perspective, a 'path' is a tuple consisting of a
683  * client or end device, a host controller which provides device
684  * identification and transport services (pHCI), and bus specific unit
685  * addressing information.  A path may be decorated with properties which
686  * describe the capabilities of the path; such properties are analogous to
687  * device node and minor node properties.
688  *
689  * The framework maintains link list of mdi_pathinfo nodes created by every
690  * pHCI driver instance via the pi_phci_link linkage; this is used (for example)
691  * to make sure that all relevant pathinfo nodes are freed before the pHCI
692  * is unregistered.
693  *
694  * Locking order:
695  *
696  * _NOTE(LOCK_ORDER(mdi_phci::ph_mutex mdi_pathinfo::pi_mutex))		XXX
697  * _NOTE(LOCK_ORDER(mdi_client::ct_mutex mdi_pathinfo::pi_mutex))	XXX
698  * _NOTE(LOCK_ORDER(mdi_phci::ph_mutex mdi_client::ct_mutex))		XXX
699  * _NOTE(LOCK_ORDER(devinfo_tree_lock mdi_pathinfo::pi_mutex))		XXX
700  *
701  * mdi_pathinfo node structure definition
702  */
703 struct mdi_pathinfo {
704 	/* protected by MDI_PHCI_LOCK ph_mutex... */
705 	struct mdi_pathinfo	*pi_phci_link;	 /* next path in phci list */
706 	mdi_phci_t		*pi_phci;	/* pHCI dev_info node	*/
707 
708 	/* protected by MDI_CLIENT_LOCK ct_mutex... */
709 	struct mdi_pathinfo	*pi_client_link; /* next path in client list */
710 	mdi_client_t		*pi_client;	/* client		*/
711 
712 	/* protected by MDI_VHCI_CLIENT_LOCK vh_client_mutex... */
713 	char			*pi_addr;	/* path unit address	*/
714 	int			pi_path_instance; /* path instance */
715 
716 	/* protected by MDI_PI_LOCK pi_mutex... */
717 	kmutex_t		pi_mutex;	/* per path mutex	*/
718 	mdi_pathinfo_state_t	pi_state;	/* path state		*/
719 	mdi_pathinfo_state_t	pi_old_state;	/* path state		*/
720 	kcondvar_t		pi_state_cv;	/* path state condvar	*/
721 	nvlist_t		*pi_prop;	/* Properties		*/
722 	void			*pi_cprivate;	/* client private info	*/
723 	void			*pi_pprivate;	/* phci private info	*/
724 	int			pi_ref_cnt;	/* pi reference count	*/
725 	kcondvar_t		pi_ref_cv;	/* condition variable	*/
726 	struct mdi_pi_kstats	*pi_kstats;	/* aggregate kstats */
727 	int			pi_pm_held;	/* phci's kidsup incremented */
728 	int			pi_preferred;	/* Preferred path 	*/
729 	void			*pi_vprivate;	/* vhci private info	*/
730 };
731 
732 /*
733  * pathinfo statistics:
734  *
735  * The mpxio architecture allows for multiple pathinfo nodes for each
736  * client-pHCI combination.  For statistics purposes, these statistics are
737  * aggregated into a single client-pHCI set of kstats.
738  */
739 struct mdi_pi_kstats {
740 	int	pi_kstat_ref;		/* # paths aggregated, also a ref cnt */
741 	kstat_t	*pi_kstat_iostats;	/* mdi:iopath statistic set */
742 	kstat_t *pi_kstat_errstats;	/* error statistics */
743 };
744 
745 /*
746  * pathinfo error kstat
747  */
748 struct pi_errs {
749 	struct kstat_named pi_softerrs;		/* "Soft" Error */
750 	struct kstat_named pi_harderrs;		/* "Hard" Error */
751 	struct kstat_named pi_transerrs;	/* Transport Errors */
752 	struct kstat_named pi_icnt_busy;	/* Interconnect Busy */
753 	struct kstat_named pi_icnt_errors;	/* Interconnect Errors */
754 	struct kstat_named pi_phci_rsrc;	/* pHCI No Resources */
755 	struct kstat_named pi_phci_localerr;	/* pHCI Local Errors */
756 	struct kstat_named pi_phci_invstate;	/* pHCI Invalid State */
757 	struct kstat_named pi_failedfrom;	/* Failover: Failed From */
758 	struct kstat_named pi_failedto;		/* Failover: Failed To */
759 };
760 
761 /*
762  * increment an error counter
763  */
764 #define	MDI_PI_ERRSTAT(pip, x) { \
765 	if (MDI_PI((pip))->pi_kstats != NULL) { \
766 		struct pi_errs *pep; \
767 		pep = MDI_PI(pip)->pi_kstats->pi_kstat_errstats->ks_data; \
768 		pep->x.value.ui32++; \
769 	} \
770 }
771 
772 /*
773  * error codes which can be passed to MDI_PI_ERRSTAT
774  */
775 #define	MDI_PI_SOFTERR	pi_softerrs
776 #define	MDI_PI_HARDERR	pi_harderrs
777 #define	MDI_PI_TRANSERR	pi_transerrs
778 #define	MDI_PI_ICNTBUSY	pi_icnt_busy
779 #define	MDI_PI_ICNTERR	pi_icnt_errors
780 #define	MDI_PI_PHCIRSRC	pi_phci_rsrc
781 #define	MDI_PI_PHCILOCL	pi_phci_localerr
782 #define	MDI_PI_PHCIINVS	pi_phci_invstate
783 #define	MDI_PI_FAILFROM	pi_failedfrom
784 #define	MDI_PI_FAILTO	pi_failedto
785 
786 #define	MDI_PI(type)			((struct mdi_pathinfo *)(type))
787 
788 #define	MDI_PI_LOCK(pip)		mutex_enter(&MDI_PI(pip)->pi_mutex)
789 #define	MDI_PI_TRYLOCK(pip)		mutex_tryenter(&MDI_PI(pip)->pi_mutex)
790 #define	MDI_PI_UNLOCK(pip)		mutex_exit(&MDI_PI(pip)->pi_mutex)
791 #ifdef	DEBUG
792 #define	MDI_PI_LOCKED(pip)		MUTEX_HELD(&MDI_PI(pip)->pi_mutex)
793 #endif	/* DEBUG */
794 
795 #define	MDI_PI_HOLD(pip)		(++MDI_PI(pip)->pi_ref_cnt)
796 #define	MDI_PI_RELE(pip)		(--MDI_PI(pip)->pi_ref_cnt)
797 
798 #define	MDI_EXT_STATE_CHANGE		0x10000000
799 
800 
801 #define	MDI_DISABLE_OP			0x1
802 #define	MDI_ENABLE_OP			0x2
803 #define	MDI_BEFORE_STATE_CHANGE		0x4
804 #define	MDI_AFTER_STATE_CHANGE		0x8
805 #define	MDI_SYNC_FLAG			0x10
806 
807 #define	MDI_PI_STATE(pip)						\
808 	(MDI_PI((pip))->pi_state & MDI_PATHINFO_STATE_MASK)
809 #define	MDI_PI_OLD_STATE(pip)						\
810 	(MDI_PI((pip))->pi_old_state & MDI_PATHINFO_STATE_MASK)
811 
812 #define	MDI_PI_EXT_STATE(pip)						\
813 	(MDI_PI((pip))->pi_state & MDI_PATHINFO_EXT_STATE_MASK)
814 #define	MDI_PI_OLD_EXT_STATE(pip)					\
815 	(MDI_PI((pip))->pi_old_state & MDI_PATHINFO_EXT_STATE_MASK)
816 
817 #define	MDI_PI_SET_TRANSIENT(pip)					{\
818 	ASSERT(MDI_PI_LOCKED(pip));					\
819 	MDI_PI(pip)->pi_state |= MDI_PATHINFO_STATE_TRANSIENT;		}
820 #define	MDI_PI_CLEAR_TRANSIENT(pip)					{\
821 	ASSERT(MDI_PI_LOCKED(pip));					\
822 	MDI_PI(pip)->pi_state &= ~MDI_PATHINFO_STATE_TRANSIENT;		}
823 #define	MDI_PI_IS_TRANSIENT(pip) \
824 	(MDI_PI(pip)->pi_state & MDI_PATHINFO_STATE_TRANSIENT)
825 
826 #define	MDI_PI_SET_USER_DISABLE(pip)					{\
827 	ASSERT(MDI_PI_LOCKED(pip));					\
828 	MDI_PI(pip)->pi_state |= MDI_PATHINFO_STATE_USER_DISABLE;	}
829 #define	MDI_PI_SET_DRV_DISABLE(pip)					{\
830 	ASSERT(MDI_PI_LOCKED(pip));					\
831 	MDI_PI(pip)->pi_state |= MDI_PATHINFO_STATE_DRV_DISABLE;	}
832 #define	MDI_PI_SET_DRV_DISABLE_TRANS(pip)				{\
833 	ASSERT(MDI_PI_LOCKED(pip));					\
834 	MDI_PI(pip)->pi_state |= MDI_PATHINFO_STATE_DRV_DISABLE_TRANSIENT; }
835 
836 #define	MDI_PI_SET_USER_ENABLE(pip)					{\
837 	ASSERT(MDI_PI_LOCKED(pip));					\
838 	MDI_PI(pip)->pi_state &= ~MDI_PATHINFO_STATE_USER_DISABLE;	}
839 #define	MDI_PI_SET_DRV_ENABLE(pip)					{\
840 	ASSERT(MDI_PI_LOCKED(pip));					\
841 	MDI_PI(pip)->pi_state &= ~MDI_PATHINFO_STATE_DRV_DISABLE;	}
842 #define	MDI_PI_SET_DRV_ENABLE_TRANS(pip)				{\
843 	ASSERT(MDI_PI_LOCKED(pip));					\
844 	MDI_PI(pip)->pi_state &= ~MDI_PATHINFO_STATE_DRV_DISABLE_TRANSIENT; }
845 
846 #define	MDI_PI_IS_USER_DISABLE(pip)					\
847 	(MDI_PI(pip)->pi_state & MDI_PATHINFO_STATE_USER_DISABLE)
848 #define	MDI_PI_IS_DRV_DISABLE(pip)					\
849 	(MDI_PI(pip)->pi_state & MDI_PATHINFO_STATE_DRV_DISABLE)
850 #define	MDI_PI_IS_DRV_DISABLE_TRANSIENT(pip)				\
851 	(MDI_PI(pip)->pi_state & MDI_PATHINFO_STATE_DRV_DISABLE_TRANSIENT)
852 
853 #define	MDI_PI_IS_DISABLE(pip)						\
854 	(MDI_PI_IS_USER_DISABLE(pip) ||					\
855 	MDI_PI_IS_DRV_DISABLE(pip) ||					\
856 	MDI_PI_IS_DRV_DISABLE_TRANSIENT(pip))
857 
858 #define	MDI_PI_IS_INIT(pip)						\
859 	((MDI_PI(pip)->pi_state & MDI_PATHINFO_STATE_MASK) ==		\
860 		MDI_PATHINFO_STATE_INIT)
861 
862 #define	MDI_PI_IS_INITING(pip)						\
863 	((MDI_PI(pip)->pi_state & ~MDI_PATHINFO_EXT_STATE_MASK) ==	\
864 		(MDI_PATHINFO_STATE_INIT | MDI_PATHINFO_STATE_TRANSIENT))
865 
866 #define	MDI_PI_SET_INIT(pip)						{\
867 	ASSERT(MDI_PI_LOCKED(pip));					\
868 	MDI_PI(pip)->pi_state = MDI_PATHINFO_STATE_INIT;		}
869 
870 #define	MDI_PI_SET_ONLINING(pip)					{\
871 	uint32_t	ext_state;					\
872 	ASSERT(MDI_PI_LOCKED(pip));					\
873 	ext_state = MDI_PI(pip)->pi_state & MDI_PATHINFO_EXT_STATE_MASK; \
874 	MDI_PI(pip)->pi_old_state = MDI_PI_STATE(pip);			\
875 	MDI_PI(pip)->pi_state =						\
876 	(MDI_PATHINFO_STATE_ONLINE | MDI_PATHINFO_STATE_TRANSIENT);	\
877 	MDI_PI(pip)->pi_state |= ext_state;				}
878 
879 #define	MDI_PI_IS_ONLINING(pip)						\
880 	((MDI_PI(pip)->pi_state & ~MDI_PATHINFO_EXT_STATE_MASK) ==	\
881 	(MDI_PATHINFO_STATE_ONLINE | MDI_PATHINFO_STATE_TRANSIENT))
882 
883 #define	MDI_PI_SET_ONLINE(pip)						{\
884 	uint32_t	ext_state;					\
885 	ASSERT(MDI_PI_LOCKED(pip));					\
886 	ext_state = MDI_PI(pip)->pi_state & MDI_PATHINFO_EXT_STATE_MASK; \
887 	MDI_PI(pip)->pi_state = MDI_PATHINFO_STATE_ONLINE;		\
888 	MDI_PI(pip)->pi_state |= ext_state;				}
889 
890 #define	MDI_PI_IS_ONLINE(pip)						\
891 	((MDI_PI(pip)->pi_state & MDI_PATHINFO_STATE_MASK) ==		\
892 	MDI_PATHINFO_STATE_ONLINE)
893 
894 #define	MDI_PI_SET_OFFLINING(pip)					{\
895 	uint32_t	ext_state;					\
896 	ASSERT(MDI_PI_LOCKED(pip));					\
897 	ext_state = MDI_PI(pip)->pi_state & MDI_PATHINFO_EXT_STATE_MASK; \
898 	MDI_PI(pip)->pi_old_state = MDI_PI_STATE(pip);			\
899 	MDI_PI(pip)->pi_state =						\
900 	(MDI_PATHINFO_STATE_OFFLINE | MDI_PATHINFO_STATE_TRANSIENT);	\
901 	MDI_PI(pip)->pi_state |= ext_state;				}
902 
903 #define	MDI_PI_IS_OFFLINING(pip)					\
904 	((MDI_PI(pip)->pi_state & ~MDI_PATHINFO_EXT_STATE_MASK) ==	\
905 	(MDI_PATHINFO_STATE_OFFLINE | MDI_PATHINFO_STATE_TRANSIENT))
906 
907 #define	MDI_PI_SET_OFFLINE(pip)						{\
908 	uint32_t	ext_state;					\
909 	ASSERT(MDI_PI_LOCKED(pip));					\
910 	ext_state = MDI_PI(pip)->pi_state & MDI_PATHINFO_EXT_STATE_MASK; \
911 	MDI_PI(pip)->pi_state = MDI_PATHINFO_STATE_OFFLINE;		\
912 	MDI_PI(pip)->pi_state |= ext_state;				}
913 
914 #define	MDI_PI_IS_OFFLINE(pip)						\
915 	((MDI_PI(pip)->pi_state & MDI_PATHINFO_STATE_MASK) ==		\
916 	MDI_PATHINFO_STATE_OFFLINE)
917 
918 #define	MDI_PI_SET_STANDBYING(pip)					{\
919 	uint32_t	ext_state;					\
920 	ASSERT(MDI_PI_LOCKED(pip));					\
921 	ext_state = MDI_PI(pip)->pi_state & MDI_PATHINFO_EXT_STATE_MASK; \
922 	MDI_PI(pip)->pi_old_state = MDI_PI_STATE(pip);			\
923 	MDI_PI(pip)->pi_state =						\
924 	(MDI_PATHINFO_STATE_STANDBY | MDI_PATHINFO_STATE_TRANSIENT);	\
925 	MDI_PI(pip)->pi_state |= ext_state;				}
926 
927 #define	MDI_PI_SET_STANDBY(pip)						{\
928 	uint32_t	ext_state;					\
929 	ASSERT(MDI_PI_LOCKED(pip));					\
930 	ext_state = MDI_PI(pip)->pi_state & MDI_PATHINFO_EXT_STATE_MASK; \
931 	MDI_PI(pip)->pi_state = MDI_PATHINFO_STATE_STANDBY;		\
932 	MDI_PI(pip)->pi_state |= ext_state;				}
933 
934 #define	MDI_PI_IS_STANDBY(pip)						\
935 	((MDI_PI(pip)->pi_state & MDI_PATHINFO_STATE_MASK) ==		\
936 	MDI_PATHINFO_STATE_STANDBY)
937 
938 #define	MDI_PI_SET_FAULTING(pip)					{\
939 	uint32_t	ext_state;					\
940 	ASSERT(MDI_PI_LOCKED(pip));					\
941 	ext_state = MDI_PI(pip)->pi_state & MDI_PATHINFO_EXT_STATE_MASK; \
942 	MDI_PI(pip)->pi_old_state = MDI_PI_STATE(pip);			\
943 	MDI_PI(pip)->pi_state =						\
944 	    (MDI_PATHINFO_STATE_FAULT | MDI_PATHINFO_STATE_TRANSIENT);	\
945 	MDI_PI(pip)->pi_state |= ext_state;				}
946 
947 #define	MDI_PI_SET_FAULT(pip)						{\
948 	uint32_t	ext_state;					\
949 	ASSERT(MDI_PI_LOCKED(pip));					\
950 	ext_state = MDI_PI(pip)->pi_state & MDI_PATHINFO_EXT_STATE_MASK; \
951 	MDI_PI(pip)->pi_state = MDI_PATHINFO_STATE_FAULT;		\
952 	MDI_PI(pip)->pi_state |= ext_state;				}
953 
954 #define	MDI_PI_IS_FAULT(pip)						\
955 	((MDI_PI(pip)->pi_state & MDI_PATHINFO_STATE_MASK) ==		\
956 	MDI_PATHINFO_STATE_FAULT)
957 
958 #define	MDI_PI_IS_SUSPENDED(pip)					\
959 	((MDI_PI(pip))->pi_phci->ph_flags & MDI_PHCI_FLAGS_SUSPEND)
960 
961 /*
962  * mdi_vhcache_client, mdi_vhcache_pathinfo, and mdi_vhcache_phci structures
963  * hold the vhci to phci client mappings of the on-disk vhci busconfig cache.
964  */
965 
966 /* phci structure of vhci cache */
967 typedef struct mdi_vhcache_phci {
968 	char			*cphci_path;	/* phci path name */
969 	uint32_t		cphci_id;	/* used when building nvlist */
970 	mdi_phci_t		*cphci_phci;	/* pointer to actual phci */
971 	struct mdi_vhcache_phci	*cphci_next;	/* next in vhci phci list */
972 } mdi_vhcache_phci_t;
973 
974 /* pathinfo structure of vhci cache */
975 typedef struct mdi_vhcache_pathinfo {
976 	char			*cpi_addr;	/* path address */
977 	mdi_vhcache_phci_t	*cpi_cphci;	/* phci the path belongs to */
978 	struct mdi_pathinfo	*cpi_pip;	/* ptr to actual pathinfo */
979 	uint32_t		cpi_flags;	/* see below */
980 	struct mdi_vhcache_pathinfo *cpi_next;	/* next path for the client */
981 } mdi_vhcache_pathinfo_t;
982 
983 /*
984  * cpi_flags
985  *
986  * MDI_CPI_HINT_PATH_DOES_NOT_EXIST - set when configuration of the path has
987  * failed.
988  */
989 #define	MDI_CPI_HINT_PATH_DOES_NOT_EXIST	0x0001
990 
991 /* client structure of vhci cache */
992 typedef struct mdi_vhcache_client {
993 	char			*cct_name_addr;	/* client address */
994 	mdi_vhcache_pathinfo_t	*cct_cpi_head;	/* client's path list head */
995 	mdi_vhcache_pathinfo_t	*cct_cpi_tail;	/* client's path list tail */
996 	struct mdi_vhcache_client *cct_next;	/* next in vhci client list */
997 } mdi_vhcache_client_t;
998 
999 /* vhci cache structure - one for vhci instance */
1000 typedef struct mdi_vhci_cache {
1001 	mdi_vhcache_phci_t	*vhcache_phci_head;	/* phci list head */
1002 	mdi_vhcache_phci_t	*vhcache_phci_tail;	/* phci list tail */
1003 	mdi_vhcache_client_t	*vhcache_client_head;	/* client list head */
1004 	mdi_vhcache_client_t	*vhcache_client_tail;	/* client list tail */
1005 	mod_hash_t		*vhcache_client_hash;	/* client hash */
1006 	int			vhcache_flags;		/* see below */
1007 	int64_t			vhcache_clean_time;	/* last clean time */
1008 	krwlock_t		vhcache_lock;		/* cache lock */
1009 } mdi_vhci_cache_t;
1010 
1011 /* vhcache_flags */
1012 #define	MDI_VHCI_CACHE_SETUP_DONE	0x0001	/* cache setup completed */
1013 
1014 /* vhci bus config structure - one for vhci instance */
1015 typedef struct mdi_vhci_config {
1016 	char			*vhc_vhcache_filename;	/* on-disk file name */
1017 	mdi_vhci_cache_t	vhc_vhcache;		/* vhci cache */
1018 	kmutex_t		vhc_lock;		/* vhci config lock */
1019 	kcondvar_t		vhc_cv;
1020 	int			vhc_flags;		/* see below */
1021 
1022 	/* flush vhci cache when lbolt reaches vhc_flush_at_ticks */
1023 	clock_t			vhc_flush_at_ticks;
1024 
1025 	/*
1026 	 * Head and tail of the client list whose paths are being configured
1027 	 * asynchronously. vhc_acc_count is the number of clients on this list.
1028 	 * vhc_acc_thrcount is the number threads running to configure
1029 	 * the paths for these clients.
1030 	 */
1031 	struct mdi_async_client_config *vhc_acc_list_head;
1032 	struct mdi_async_client_config *vhc_acc_list_tail;
1033 	int			vhc_acc_count;
1034 	int			vhc_acc_thrcount;
1035 
1036 	/* callback id - for flushing the cache during system shutdown */
1037 	callb_id_t		vhc_cbid;
1038 
1039 	/*
1040 	 * vhc_path_discovery_boot -	number of times path discovery will be
1041 	 *				attempted during early boot.
1042 	 * vhc_path_discovery_postboot	number of times path discovery will be
1043 	 *				attempted during late boot.
1044 	 * vhc_path_discovery_cutoff_time - time at which paths were last
1045 	 *				discovered  + some timeout
1046 	 */
1047 	int			vhc_path_discovery_boot;
1048 	int			vhc_path_discovery_postboot;
1049 	int64_t			vhc_path_discovery_cutoff_time;
1050 } mdi_vhci_config_t;
1051 
1052 /* vhc_flags */
1053 #define	MDI_VHC_SINGLE_THREADED		0x0001	/* config single threaded */
1054 #define	MDI_VHC_EXIT			0x0002	/* exit all config activity */
1055 #define	MDI_VHC_VHCACHE_DIRTY		0x0004	/* cache dirty */
1056 #define	MDI_VHC_VHCACHE_FLUSH_THREAD	0x0008	/* cache flush thead running */
1057 #define	MDI_VHC_VHCACHE_FLUSH_ERROR	0x0010	/* failed to flush cache */
1058 #define	MDI_VHC_READONLY_FS		0x0020	/* filesys is readonly */
1059 
1060 typedef struct mdi_phys_path {
1061 	char			*phys_path;
1062 	struct mdi_phys_path	*phys_path_next;
1063 } mdi_phys_path_t;
1064 
1065 /*
1066  * Lookup tokens are used to cache the result of the vhci cache client lookup
1067  * operations (to reduce the number of real lookup operations).
1068  */
1069 typedef struct mdi_vhcache_lookup_token {
1070 	mdi_vhcache_client_t	*lt_cct;		/* vhcache client */
1071 	int64_t			lt_cct_lookup_time;	/* last lookup time */
1072 } mdi_vhcache_lookup_token_t;
1073 
1074 /* asynchronous configuration of client paths */
1075 typedef struct mdi_async_client_config {
1076 	char			*acc_ct_name;	/* client name */
1077 	char			*acc_ct_addr;	/* client address */
1078 	mdi_phys_path_t		*acc_phclient_path_list_head;	/* path head */
1079 	mdi_vhcache_lookup_token_t acc_token;	/* lookup token */
1080 	struct mdi_async_client_config *acc_next; /* next in vhci acc list */
1081 } mdi_async_client_config_t;
1082 
1083 /*
1084  * vHCI driver instance registration/unregistration
1085  *
1086  * mdi_vhci_register() is called by a vHCI driver to register itself as the
1087  * manager of devices from a particular 'class'.  This should be called from
1088  * attach(9e).
1089  *
1090  * mdi_vhci_unregister() is called from detach(9E) to unregister a vHCI
1091  * instance from the framework.
1092  */
1093 int		mdi_vhci_register(char *, dev_info_t *, mdi_vhci_ops_t *, int);
1094 int		mdi_vhci_unregister(dev_info_t *, int);
1095 
1096 /*
1097  * Utility functions
1098  */
1099 int		mdi_phci_get_path_count(dev_info_t *);
1100 dev_info_t	*mdi_phci_path2devinfo(dev_info_t *, caddr_t);
1101 
1102 
1103 /*
1104  * Path Selection Functions:
1105  *
1106  * mdi_select_path() is called by a vHCI driver to select to which path an
1107  * I/O request should be routed.  The caller passes the 'buf' structure as
1108  * one of the parameters.  The mpxio framework uses the buf's contents to
1109  * maintain per path statistics (total I/O size / count pending).  If more
1110  * than one online path is available, the framework automatically selects
1111  * a suitable one.  If a failover operation is active for this client device
1112  * the call fails, returning MDI_BUSY.
1113  *
1114  * By default this function returns a suitable path in the 'online' state,
1115  * based on the current load balancing policy.  Currently we support
1116  * LOAD_BALANCE_NONE (Previously selected online path will continue to be
1117  * used as long as the path is usable) and LOAD_BALANCE_RR (Online paths
1118  * will be selected in a round robin fashion).  The load balancing scheme
1119  * can be configured in the vHCI driver's configuration file (driver.conf).
1120  *
1121  * vHCI drivers may override this default behaviour by specifying appropriate
1122  * flags.  If start_pip is specified (non NULL), it is used as the routine's
1123  * starting point; it starts walking from there to find the next appropriate
1124  * path.
1125  *
1126  * The following values for 'flags' are currently defined, the third argument
1127  * to mdi_select_path depends on the flags used.
1128  *
1129  *   <none>:				default, arg is pip
1130  *   MDI_SELECT_ONLINE_PATH:		select an ONLINE path preferred-first,
1131  *					arg is pip
1132  *   MDI_SELECT_STANDBY_PATH:		select a STANDBY path, arg is pip
1133  *   MDI_SELECT_USER_DISABLE_PATH:	select user disable for failover and
1134  *					auto_failback
1135  *   MDI_SELECT_PATH_INSTANCE:		select a specific path, arg is
1136  *					path instance
1137  *   MDI_SELECT_NO_PREFERRED:		select path without preferred-first
1138  *
1139  * The selected paths are returned in an mdi_hold_path() state (pi_ref_cnt),
1140  * caller should release the hold by calling mdi_rele_path() at the end of
1141  * operation.
1142  */
1143 int		mdi_select_path(dev_info_t *, struct buf *, int,
1144 		    void *, mdi_pathinfo_t **);
1145 int		mdi_set_lb_policy(dev_info_t *, client_lb_t);
1146 int		mdi_set_lb_region_size(dev_info_t *, int);
1147 client_lb_t	mdi_get_lb_policy(dev_info_t *);
1148 
1149 /*
1150  * flags for mdi_select_path() routine
1151  */
1152 #define	MDI_SELECT_ONLINE_PATH		0x0001
1153 #define	MDI_SELECT_STANDBY_PATH		0x0002
1154 #define	MDI_SELECT_USER_DISABLE_PATH	0x0004
1155 #define	MDI_SELECT_PATH_INSTANCE	0x0008
1156 #define	MDI_SELECT_NO_PREFERRED		0x0010
1157 
1158 /*
1159  * MDI client device utility functions
1160  */
1161 int		mdi_client_get_path_count(dev_info_t *);
1162 dev_info_t	*mdi_client_path2devinfo(dev_info_t *, caddr_t);
1163 
1164 /*
1165  * Failover:
1166  *
1167  * The vHCI driver calls mdi_failover() to initiate a failover operation.
1168  * mdi_failover() calls back into the vHCI driver's vo_failover()
1169  * entry point to perform the actual failover operation.  The reason
1170  * for requiring the vHCI driver to initiate failover by calling
1171  * mdi_failover(), instead of directly executing vo_failover() itself,
1172  * is to ensure that the mdi framework can keep track of the client
1173  * state properly.  Additionally, mdi_failover() provides as a
1174  * convenience the option of performing the failover operation
1175  * synchronously or asynchronously
1176  *
1177  * Upon successful completion of the failover operation, the paths that were
1178  * previously ONLINE will be in the STANDBY state, and the newly activated
1179  * paths will be in the ONLINE state.
1180  *
1181  * The flags modifier determines whether the activation is done synchronously
1182  */
1183 int mdi_failover(dev_info_t *, dev_info_t *, int);
1184 
1185 /*
1186  * Client device failover mode of operation
1187  */
1188 #define	MDI_FAILOVER_SYNC	1	/* Syncronous Failover		*/
1189 #define	MDI_FAILOVER_ASYNC	2	/* Asyncronous Failover		*/
1190 
1191 /*
1192  * mdi_pathinfo node kstat functions.
1193  */
1194 int mdi_pi_kstat_exists(mdi_pathinfo_t *);
1195 int mdi_pi_kstat_create(mdi_pathinfo_t *pip, char *ks_name);
1196 void mdi_pi_kstat_iosupdate(mdi_pathinfo_t *, struct buf *);
1197 
1198 /*
1199  * mdi_pathinfo node extended state change functions.
1200  */
1201 int mdi_pi_get_state2(mdi_pathinfo_t *, mdi_pathinfo_state_t *, uint32_t *);
1202 int mdi_pi_get_preferred(mdi_pathinfo_t *);
1203 
1204 /*
1205  * mdi_pathinfo node member functions
1206  */
1207 void *mdi_pi_get_client_private(mdi_pathinfo_t *);
1208 void mdi_pi_set_client_private(mdi_pathinfo_t *, void *);
1209 void mdi_pi_set_state(mdi_pathinfo_t *, mdi_pathinfo_state_t);
1210 void mdi_pi_set_preferred(mdi_pathinfo_t *, int);
1211 
1212 /* get/set vhci private data */
1213 void *mdi_client_get_vhci_private(dev_info_t *);
1214 void mdi_client_set_vhci_private(dev_info_t *, void *);
1215 void *mdi_phci_get_vhci_private(dev_info_t *);
1216 void mdi_phci_set_vhci_private(dev_info_t *, void *);
1217 void *mdi_pi_get_vhci_private(mdi_pathinfo_t *);
1218 void mdi_pi_set_vhci_private(mdi_pathinfo_t *, void *);
1219 
1220 /*
1221  * mdi_pathinfo Property utilities
1222  */
1223 int mdi_prop_size(mdi_pathinfo_t *, size_t *);
1224 int mdi_prop_pack(mdi_pathinfo_t *, char **, uint_t);
1225 
1226 /* obsolete interface, to be removed */
1227 void mdi_get_next_path(dev_info_t *, mdi_pathinfo_t *, mdi_pathinfo_t **);
1228 int mdi_get_component_type(dev_info_t *);
1229 
1230 #endif	/* _KERNEL */
1231 
1232 #ifdef	__cplusplus
1233 }
1234 #endif
1235 
1236 #endif	/* _SYS_MDI_IMPLDEFS_H */
1237