xref: /titanic_51/usr/src/uts/sun4v/io/vio_util.c (revision 1a6f4459015a5e6c608d53b5942bd44755933cd5)
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 #include <sys/types.h>
28 #include <sys/sysmacros.h>
29 #include <sys/errno.h>
30 #include <sys/kmem.h>
31 #include <sys/ksynch.h>
32 #include <sys/stream.h>
33 #include <sys/ddi.h>
34 #include <sys/sunddi.h>
35 #include <sys/vio_util.h>
36 
37 static int vio_pool_cleanup_retries = 10;	/* Max retries to free pool */
38 static int vio_pool_cleanup_delay = 10000;	/* 10ms */
39 
40 /*
41  * Create a pool of mblks from which future vio_allocb() requests
42  * will be serviced.
43  *
44  * NOTE: num_mblks has to non-zero and a power-of-2
45  *
46  * Returns
47  *	0 on success
48  *	EINVAL if num_mblks is zero or not a power of 2.
49  *	ENOSPC if the pool could not be created due to alloc failures.
50  */
51 int
52 vio_create_mblks(uint64_t num_mblks, size_t mblk_size, vio_mblk_pool_t **poolp)
53 {
54 	vio_mblk_pool_t		*vmplp;
55 	vio_mblk_t		*vmp;
56 	uint8_t			*datap;
57 	int			i;
58 
59 	if (!(num_mblks) || (!ISP2(num_mblks))) {
60 		*poolp = 0;
61 		return (EINVAL);
62 	}
63 
64 	vmplp = kmem_zalloc(sizeof (*vmplp), KM_SLEEP);
65 	vmplp->quelen = num_mblks;
66 	vmplp->quemask = num_mblks - 1; /* expects quelen is power-of-2 */
67 	vmplp->mblk_size = mblk_size;
68 
69 	mutex_init(&vmplp->hlock, NULL, MUTEX_DRIVER,
70 	    DDI_INTR_PRI(DDI_INTR_SOFTPRI_DEFAULT));
71 	mutex_init(&vmplp->tlock, NULL, MUTEX_DRIVER,
72 	    DDI_INTR_PRI(DDI_INTR_SOFTPRI_DEFAULT));
73 
74 	vmplp->basep = kmem_zalloc(num_mblks * sizeof (vio_mblk_t), KM_SLEEP);
75 	vmplp->datap = kmem_zalloc(num_mblks * mblk_size, KM_SLEEP);
76 	vmplp->nextp = NULL;
77 
78 	/* create a queue of pointers to free vio_mblk_t's */
79 	vmplp->quep = kmem_zalloc(vmplp->quelen *
80 	    sizeof (vio_mblk_t *), KM_SLEEP);
81 	vmplp->head = 0;
82 	vmplp->tail =  0;
83 
84 	for (i = 0, datap = vmplp->datap; i < num_mblks; i++) {
85 
86 		vmp = &(vmplp->basep[i]);
87 		vmp->vmplp = vmplp;
88 		vmp->datap = datap;
89 		vmp->reclaim.free_func = vio_freeb;
90 		vmp->reclaim.free_arg = (caddr_t)vmp;
91 		vmp->mp = desballoc(vmp->datap, mblk_size, BPRI_MED,
92 		    &vmp->reclaim);
93 
94 		if (vmp->mp == NULL) {
95 			/* reset tail */
96 			vmplp->tail = vmplp->head;
97 
98 			/*
99 			 * vio_destroy_mblks() frees mblks that have been
100 			 * allocated so far and then destroys the pool.
101 			 */
102 			vio_destroy_mblks(vmplp);
103 
104 			*poolp = NULL;
105 			return (ENOSPC);
106 		}
107 
108 		/* put this vmp on the free stack */
109 		vmplp->quep[vmplp->tail] = vmp;
110 		vmplp->tail = (vmplp->tail + 1) & vmplp->quemask;
111 
112 		datap += mblk_size;
113 	}
114 
115 	*poolp = vmplp;
116 	return (0);
117 }
118 
119 /*
120  * Destroy the pool of mblks. This can only succeed when
121  * all allocated mblks have been returned to the pool.
122  *
123  * It is up to the caller to ensure that no further mblks are
124  * requested from the pool after destroy has been invoked.
125  *
126  * Returns 0 on success, EINVAL if handle is invalid, or
127  * EBUSY if not all mblks reclaimed yet.
128  */
129 int
130 vio_destroy_mblks(vio_mblk_pool_t *vmplp)
131 {
132 	uint64_t	i;
133 	uint64_t	num_mblks;
134 	vio_mblk_t	*vmp;
135 	int		pool_cleanup_retries = 0;
136 
137 
138 	if (vmplp == NULL)
139 		return (EINVAL);
140 
141 	/*
142 	 * We can only destroy the pool once all the mblks have
143 	 * been reclaimed.
144 	 */
145 	do {
146 		if (vmplp->head == vmplp->tail) {
147 			break;
148 		}
149 
150 		/* some mblks still in use */
151 		drv_usecwait(vio_pool_cleanup_delay);
152 	} while (++pool_cleanup_retries < vio_pool_cleanup_retries);
153 
154 	if (vmplp->head != vmplp->tail) {
155 		return (EBUSY);
156 	}
157 
158 	num_mblks = vmplp->quelen;
159 
160 	/*
161 	 * Set pool flag to tell vio_freeb() which is invoked from freeb(),
162 	 * that it is being called in the context of vio_destroy_mblks().
163 	 * This results in freeing only mblk_t and dblk_t structures for
164 	 * each mp. The associated data buffers are freed below as one big
165 	 * chunk through kmem_free(vmplp->datap).
166 	 */
167 	vmplp->flag |= VMPL_FLAG_DESTROYING;
168 	for (i = 0; i < num_mblks; i++) {
169 		vmp = &(vmplp->basep[i]);
170 		/*
171 		 * It is possible that mblks have been allocated only upto
172 		 * a certain index and the entire quelen has not been
173 		 * initialized. This might happen due to desballoc() failure
174 		 * while creating the pool. The below check handles this
175 		 * condition.
176 		 */
177 		if (vmp->mp != NULL)
178 			freeb(vmp->mp);
179 	}
180 	vmplp->flag &= ~(VMPL_FLAG_DESTROYING);
181 
182 	kmem_free(vmplp->basep, num_mblks * sizeof (vio_mblk_t));
183 	kmem_free(vmplp->datap, num_mblks * vmplp->mblk_size);
184 	kmem_free(vmplp->quep, num_mblks * sizeof (vio_mblk_t *));
185 
186 	mutex_destroy(&vmplp->hlock);
187 	mutex_destroy(&vmplp->tlock);
188 
189 	kmem_free(vmplp, sizeof (*vmplp));
190 
191 	return (0);
192 }
193 
194 /*
195  * Allocate a mblk from the free pool if one is available.
196  * Otherwise returns NULL.
197  */
198 mblk_t *
199 vio_allocb(vio_mblk_pool_t *vmplp)
200 {
201 	vio_mblk_t	*vmp = NULL;
202 	mblk_t		*mp = NULL;
203 	uint32_t	head;
204 
205 	mutex_enter(&vmplp->hlock);
206 	head = (vmplp->head + 1) & vmplp->quemask;
207 	if (head != vmplp->tail) {
208 		/* we have free mblks */
209 		vmp = vmplp->quep[vmplp->head];
210 		mp = vmp->mp;
211 		vmplp->head = head;
212 	}
213 	mutex_exit(&vmplp->hlock);
214 
215 	return (mp);
216 }
217 
218 /*
219  * Return a mblk to the free pool. Invoked when the upper IP
220  * layers do freemsg() etc on the mblk they were passed.
221  */
222 void
223 vio_freeb(void *arg)
224 {
225 	vio_mblk_t	*vmp = (vio_mblk_t *)arg;
226 	vio_mblk_pool_t	*vmplp = vmp->vmplp;
227 
228 	if (vmplp->flag & VMPL_FLAG_DESTROYING) {
229 		/*
230 		 * This flag indicates that freeb() is being called from
231 		 * vio_destroy_mblks().
232 		 * We don't need to alloc a new mblk_t/dblk_t pair for
233 		 * this data buffer, return from here and the data buffer
234 		 * itself will be freed in vio_destroy_mblks().
235 		 */
236 		return;
237 	}
238 
239 	vmp->mp = desballoc(vmp->datap, vmplp->mblk_size,
240 	    BPRI_MED, &vmp->reclaim);
241 
242 	mutex_enter(&vmplp->tlock);
243 	vmplp->quep[vmplp->tail] = vmp;
244 	vmplp->tail = (vmplp->tail + 1) & vmplp->quemask;
245 	mutex_exit(&vmplp->tlock);
246 }
247 
248 /*
249  * Create a multiple pools of mblks from which future vio_allocb()
250  * or vio_multipool_allocb() requests will be serviced.
251  *
252  * Arguments:
253  *	vmultip -- A pointer to vio_multi_pool_t structure.
254  *	num_pools -- Number of the pools.
255  *	... -- Variable arguments consisting a list of buffer sizes for
256  *		each pool and list of number of buffers for each pool.
257  *
258  * NOTE: The restrictions of vio_create_mblks() apply to this interface also.
259  *
260  * Returns 0 on success or an error returned by vio_create_mblks().
261  */
262 int
263 vio_init_multipools(vio_multi_pool_t *vmultip, int num_pools, ...)
264 {
265 	int		i;
266 	int		status;
267 	char		*tbuf;
268 	va_list		vap;
269 	vio_mblk_pool_t *fvmp = NULL;
270 
271 	/*
272 	 * Allocate memory for all of the following in one allocation.
273 	 * 	bufsz_tbl -- sizeof (uint32_t) * num_pools
274 	 * 	nbuf_tbl  -- sizeof (uint32_t) * num_pools
275 	 *	vmpp	  -- sizeof (vio_mblk_pool_t *) * numpools
276 	 */
277 	vmultip->tbsz = (sizeof (uint32_t) * num_pools) +
278 	    (sizeof (uint32_t) * num_pools) +
279 	    (sizeof (vio_mblk_pool_t *) * num_pools);
280 	tbuf = kmem_zalloc(vmultip->tbsz, KM_SLEEP);
281 	vmultip->bufsz_tbl = (uint32_t *)tbuf;
282 	vmultip->nbuf_tbl = (uint32_t *)(tbuf +
283 	    (sizeof (uint32_t) * num_pools));
284 	vmultip->vmpp = (vio_mblk_pool_t **)(tbuf +
285 	    (sizeof (uint32_t) * num_pools * 2));
286 	vmultip->num_pools = num_pools;
287 
288 	/* initialize the array first */
289 	va_start(vap, num_pools);
290 	for (i = 0; i < num_pools; i++) {
291 		vmultip->bufsz_tbl[i] = va_arg(vap, uint32_t);
292 	}
293 	for (i = 0; i < num_pools; i++) {
294 		vmultip->nbuf_tbl[i] = va_arg(vap, uint32_t);
295 	}
296 	va_end(vap);
297 
298 	for (i = 0; i < vmultip->num_pools; i++) {
299 		status = vio_create_mblks(vmultip->nbuf_tbl[i],
300 		    vmultip->bufsz_tbl[i], &vmultip->vmpp[i]);
301 		if (status != 0) {
302 			vio_destroy_multipools(vmultip, &fvmp);
303 			/* We expect to free the pools without failure here */
304 			ASSERT(fvmp == NULL);
305 			return (status);
306 		}
307 	}
308 	return (0);
309 }
310 
311 /*
312  * Destroy the multiple pools of mblks. This can only succeed when
313  * all allocated mblks have been returned to the pool.
314  *
315  * If a pool of mblks couldn't be destroyed, then the failed vio_mblk_pool_t
316  * pointers are returned via th fvmp list. Its the caller's
317  * responsibility to check this list and free them later at an appropriate
318  * time with vio_destroy_mblks().
319  *
320  * Arguments:
321  *	vmultip -- A pointer to vio_multi_pool_t structure.
322  *	fvmp -- A list in which the pools that couldn't be destroyed are
323  *		returned.
324  */
325 void
326 vio_destroy_multipools(vio_multi_pool_t *vmultip, vio_mblk_pool_t **fvmp)
327 {
328 	int i;
329 	vio_mblk_pool_t *vmp;
330 
331 	for (i = 0; i < vmultip->num_pools; i++) {
332 		if ((vmp = vmultip->vmpp[i]) != NULL) {
333 			if (vio_destroy_mblks(vmp)) {
334 				/*
335 				 * if we cannot reclaim all mblks, then
336 				 * return the pool in the failed vmp
337 				 * list(fvmp).
338 				 */
339 				vmp->nextp =  *fvmp;
340 				*fvmp = vmp;
341 			}
342 		}
343 	}
344 	if (vmultip->tbsz != 0)
345 		kmem_free(vmultip->bufsz_tbl, vmultip->tbsz);
346 	vmultip->bufsz_tbl = NULL;
347 	vmultip->nbuf_tbl = NULL;
348 	vmultip->vmpp = NULL;
349 	vmultip->num_pools = 0;
350 	vmultip->tbsz = 0;
351 }
352 
353 
354 /*
355  * Allocate an mblk from one of the free pools, but tries the pool that
356  * best fits size requested first.
357  */
358 mblk_t *
359 vio_multipool_allocb(vio_multi_pool_t *vmultip, size_t size)
360 {
361 	int i;
362 	mblk_t *mp = NULL;
363 
364 	/* Try allocating any size that fits */
365 	for (i = 0; i < vmultip->num_pools; i++) {
366 		if (size > vmultip->bufsz_tbl[i]) {
367 			continue;
368 		}
369 		mp = vio_allocb(vmultip->vmpp[i]);
370 		if (mp != NULL) {
371 			break;
372 		}
373 	}
374 	return (mp);
375 }
376 
377 /*
378  * -----------------------------------------------------------------------------
379  * LDoms versioning functions
380  *
381  * Future work: the version negotiating code in the various VIO drivers
382  * could be made common and placed here.
383  */
384 
385 /*
386  * Description:
387  *	This function checks to see if the supplied version tuple (major,minor)
388  *	is supported by the version 'ver', negotiated during the handshake
389  *	between the client and the server (ver).
390  *
391  * Assumption:
392  *	This function assumes that backward compatability is not broken in
393  *	newer minor versions of the protocol (e.g. v1.5 & v1.1 support v1.0)
394  *
395  * Return Value:
396  *	B_TRUE		- The (major,minor) version is supported
397  *	B_FALSE		- not supported
398  */
399 boolean_t
400 vio_ver_is_supported(vio_ver_t ver, uint16_t major, uint16_t minor)
401 {
402 	if ((ver.major == major) && (ver.minor >= minor))
403 		return (B_TRUE);
404 
405 	return (B_FALSE);
406 }
407