diff options
Diffstat (limited to 'drivers/infiniband/hw/qib/qib_mmap.c')
| -rw-r--r-- | drivers/infiniband/hw/qib/qib_mmap.c | 174 |
1 files changed, 174 insertions, 0 deletions
diff --git a/drivers/infiniband/hw/qib/qib_mmap.c b/drivers/infiniband/hw/qib/qib_mmap.c new file mode 100644 index 00000000000..8b73a11d571 --- /dev/null +++ b/drivers/infiniband/hw/qib/qib_mmap.c @@ -0,0 +1,174 @@ +/* + * Copyright (c) 2006, 2007, 2008, 2009 QLogic Corporation. All rights reserved. + * + * This software is available to you under a choice of one of two + * licenses. You may choose to be licensed under the terms of the GNU + * General Public License (GPL) Version 2, available from the file + * COPYING in the main directory of this source tree, or the + * OpenIB.org BSD license below: + * + * Redistribution and use in source and binary forms, with or + * without modification, are permitted provided that the following + * conditions are met: + * + * - Redistributions of source code must retain the above + * copyright notice, this list of conditions and the following + * disclaimer. + * + * - Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following + * disclaimer in the documentation and/or other materials + * provided with the distribution. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ + +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/vmalloc.h> +#include <linux/mm.h> +#include <linux/errno.h> +#include <asm/pgtable.h> + +#include "qib_verbs.h" + +/** + * qib_release_mmap_info - free mmap info structure + * @ref: a pointer to the kref within struct qib_mmap_info + */ +void qib_release_mmap_info(struct kref *ref) +{ + struct qib_mmap_info *ip = + container_of(ref, struct qib_mmap_info, ref); + struct qib_ibdev *dev = to_idev(ip->context->device); + + spin_lock_irq(&dev->pending_lock); + list_del(&ip->pending_mmaps); + spin_unlock_irq(&dev->pending_lock); + + vfree(ip->obj); + kfree(ip); +} + +/* + * open and close keep track of how many times the CQ is mapped, + * to avoid releasing it. + */ +static void qib_vma_open(struct vm_area_struct *vma) +{ + struct qib_mmap_info *ip = vma->vm_private_data; + + kref_get(&ip->ref); +} + +static void qib_vma_close(struct vm_area_struct *vma) +{ + struct qib_mmap_info *ip = vma->vm_private_data; + + kref_put(&ip->ref, qib_release_mmap_info); +} + +static struct vm_operations_struct qib_vm_ops = { + .open = qib_vma_open, + .close = qib_vma_close, +}; + +/** + * qib_mmap - create a new mmap region + * @context: the IB user context of the process making the mmap() call + * @vma: the VMA to be initialized + * Return zero if the mmap is OK. Otherwise, return an errno. + */ +int qib_mmap(struct ib_ucontext *context, struct vm_area_struct *vma) +{ + struct qib_ibdev *dev = to_idev(context->device); + unsigned long offset = vma->vm_pgoff << PAGE_SHIFT; + unsigned long size = vma->vm_end - vma->vm_start; + struct qib_mmap_info *ip, *pp; + int ret = -EINVAL; + + /* + * Search the device's list of objects waiting for a mmap call. + * Normally, this list is very short since a call to create a + * CQ, QP, or SRQ is soon followed by a call to mmap(). + */ + spin_lock_irq(&dev->pending_lock); + list_for_each_entry_safe(ip, pp, &dev->pending_mmaps, + pending_mmaps) { + /* Only the creator is allowed to mmap the object */ + if (context != ip->context || (__u64) offset != ip->offset) + continue; + /* Don't allow a mmap larger than the object. */ + if (size > ip->size) + break; + + list_del_init(&ip->pending_mmaps); + spin_unlock_irq(&dev->pending_lock); + + ret = remap_vmalloc_range(vma, ip->obj, 0); + if (ret) + goto done; + vma->vm_ops = &qib_vm_ops; + vma->vm_private_data = ip; + qib_vma_open(vma); + goto done; + } + spin_unlock_irq(&dev->pending_lock); +done: + return ret; +} + +/* + * Allocate information for qib_mmap + */ +struct qib_mmap_info *qib_create_mmap_info(struct qib_ibdev *dev, + u32 size, + struct ib_ucontext *context, + void *obj) { + struct qib_mmap_info *ip; + + ip = kmalloc(sizeof *ip, GFP_KERNEL); + if (!ip) + goto bail; + + size = PAGE_ALIGN(size); + + spin_lock_irq(&dev->mmap_offset_lock); + if (dev->mmap_offset == 0) + dev->mmap_offset = PAGE_SIZE; + ip->offset = dev->mmap_offset; + dev->mmap_offset += size; + spin_unlock_irq(&dev->mmap_offset_lock); + + INIT_LIST_HEAD(&ip->pending_mmaps); + ip->size = size; + ip->context = context; + ip->obj = obj; + kref_init(&ip->ref); + +bail: + return ip; +} + +void qib_update_mmap_info(struct qib_ibdev *dev, struct qib_mmap_info *ip, + u32 size, void *obj) +{ + size = PAGE_ALIGN(size); + + spin_lock_irq(&dev->mmap_offset_lock); + if (dev->mmap_offset == 0) + dev->mmap_offset = PAGE_SIZE; + ip->offset = dev->mmap_offset; + dev->mmap_offset += size; + spin_unlock_irq(&dev->mmap_offset_lock); + + ip->size = size; + ip->obj = obj; +} |