diff options
Diffstat (limited to 'usr/src/uts/sun4v/io/vio_util.c')
| -rw-r--r-- | usr/src/uts/sun4v/io/vio_util.c | 184 |
1 files changed, 184 insertions, 0 deletions
diff --git a/usr/src/uts/sun4v/io/vio_util.c b/usr/src/uts/sun4v/io/vio_util.c new file mode 100644 index 0000000000..42cbf34fa2 --- /dev/null +++ b/usr/src/uts/sun4v/io/vio_util.c @@ -0,0 +1,184 @@ +/* + * CDDL HEADER START + * + * The contents of this file are subject to the terms of the + * Common Development and Distribution License (the "License"). + * You may not use this file except in compliance with the License. + * + * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE + * or http://www.opensolaris.org/os/licensing. + * See the License for the specific language governing permissions + * and limitations under the License. + * + * When distributing Covered Code, include this CDDL HEADER in each + * file and include the License file at usr/src/OPENSOLARIS.LICENSE. + * If applicable, add the following below this CDDL HEADER, with the + * fields enclosed by brackets "[]" replaced with your own identifying + * information: Portions Copyright [yyyy] [name of copyright owner] + * + * CDDL HEADER END + */ + +/* + * Copyright 2006 Sun Microsystems, Inc. All rights reserved. + * Use is subject to license terms. + */ + +#pragma ident "%Z%%M% %I% %E% SMI" + +#include <sys/types.h> +#include <sys/sysmacros.h> +#include <sys/cmn_err.h> +#include <sys/errno.h> +#include <sys/kmem.h> +#include <sys/ksynch.h> +#include <sys/stream.h> +#include <sys/ddi.h> +#include <sys/sunddi.h> +#include <sys/vio_util.h> + +/* + * Create a pool of mblks from which future vio_allocb() requests + * will be serviced. + * + * NOTE: num_mblks has to non-zero and a power-of-2 + * + * Returns 0 on success or EINVAL if num_mblks is zero or not + * a power of 2. + */ +int +vio_create_mblks(uint64_t num_mblks, size_t mblk_size, vio_mblk_pool_t **poolp) +{ + vio_mblk_pool_t *vmplp; + vio_mblk_t *vmp; + uint8_t *datap; + int i; + + if (!(num_mblks) || (!ISP2(num_mblks))) { + *poolp = 0; + return (EINVAL); + } + + vmplp = kmem_zalloc(sizeof (*vmplp), KM_SLEEP); + vmplp->quelen = num_mblks; + vmplp->quemask = num_mblks - 1; /* expects quelen is power-of-2 */ + vmplp->mblk_size = mblk_size; + + mutex_init(&vmplp->hlock, NULL, MUTEX_DRIVER, + DDI_INTR_PRI(DDI_INTR_SOFTPRI_DEFAULT)); + mutex_init(&vmplp->tlock, NULL, MUTEX_DRIVER, + DDI_INTR_PRI(DDI_INTR_SOFTPRI_DEFAULT)); + + vmplp->basep = kmem_zalloc(num_mblks * sizeof (vio_mblk_t), KM_SLEEP); + vmplp->datap = kmem_zalloc(num_mblks * mblk_size, KM_SLEEP); + vmplp->nextp = NULL; + + /* create a queue of pointers to free vio_mblk_t's */ + vmplp->quep = kmem_zalloc(vmplp->quelen * sizeof (vio_mblk_t *), + KM_SLEEP); + vmplp->head = 0; + vmplp->tail = 0; + + for (i = 0, datap = vmplp->datap; i < num_mblks; i++) { + + vmp = &(vmplp->basep[i]); + vmp->vmplp = vmplp; + vmp->datap = datap; + vmp->reclaim.free_func = vio_freeb; + vmp->reclaim.free_arg = (caddr_t)vmp; + vmp->mp = desballoc(vmp->datap, mblk_size, BPRI_MED, + &vmp->reclaim); + + if (vmp->mp == NULL) + continue; + + /* put this vmp on the free stack */ + vmplp->quep[vmplp->tail] = vmp; + vmplp->tail = (vmplp->tail + 1) & vmplp->quemask; + + datap += mblk_size; + } + + *poolp = vmplp; + return (0); +} + +/* + * Destroy the pool of mblks. This can only succeed when + * all allocated mblks have been returned to the pool. + * + * It is up to the caller to ensure that no further mblks are + * requested from the pool after destroy has been invoked. + * + * Returns 0 on success, EINVAL if handle is invalid, or + * EBUSY if not all mblks reclaimed yet. + */ +int +vio_destroy_mblks(vio_mblk_pool_t *vmplp) +{ + if (vmplp == NULL) + return (EINVAL); + + /* + * We can only destroy the pool once all the mblks have + * been reclaimed. + */ + if (vmplp->head != vmplp->tail) { + /* some mblks still in use */ + return (EBUSY); + } + + kmem_free(vmplp->basep, vmplp->quelen * sizeof (vio_mblk_t)); + kmem_free(vmplp->datap, vmplp->quelen * vmplp->mblk_size); + kmem_free(vmplp->quep, vmplp->quelen * sizeof (vio_mblk_t *)); + + mutex_destroy(&vmplp->hlock); + mutex_destroy(&vmplp->tlock); + + kmem_free(vmplp, sizeof (*vmplp)); + + return (0); +} + +/* + * Allocate a mblk from the free pool if one is available. + * Otherwise returns NULL. + */ +mblk_t * +vio_allocb(vio_mblk_pool_t *vmplp) +{ + vio_mblk_t *vmp = NULL; + mblk_t *mp = NULL; + uint32_t head; + + mutex_enter(&vmplp->hlock); + head = (vmplp->head + 1) & vmplp->quemask; + if (head != vmplp->tail) { + /* we have free mblks */ + vmp = vmplp->quep[vmplp->head]; + mp = vmp->mp; + vmplp->head = head; + } + mutex_exit(&vmplp->hlock); + + return (mp); +} + +/* + * Return a mblk to the free pool. Invoked when the upper IP + * layers do freemsg() etc on the mblk they were passed. + */ +void +vio_freeb(void *arg) +{ + vio_mblk_t *vmp = (vio_mblk_t *)arg; + vio_mblk_pool_t *vmplp = vmp->vmplp; + + vmp->mp = desballoc(vmp->datap, vmplp->mblk_size, + BPRI_MED, &vmp->reclaim); + + mutex_enter(&vmplp->tlock); + vmplp->quep[vmplp->tail] = vmp; + vmplp->tail = (vmplp->tail + 1) & vmplp->quemask; + mutex_exit(&vmplp->tlock); +} |