[mirror_ubuntu-bionic-kernel.git] / drivers / infiniband / hw / ipath / ipath_mmap.c

/*
 * Copyright (c) 2006, 2007 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/vmalloc.h>
#include <linux/slab.h>
#include <linux/mm.h>
#include <linux/errno.h>
#include <asm/pgtable.h>

#include "ipath_verbs.h"

/**
 * ipath_release_mmap_info - free mmap info structure
 * @ref: a pointer to the kref within struct ipath_mmap_info
 */
void ipath_release_mmap_info(struct kref *ref)
{
	struct ipath_mmap_info *ip =
		container_of(ref, struct ipath_mmap_info, ref);
	struct ipath_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 ipath_vma_open(struct vm_area_struct *vma)
{
	struct ipath_mmap_info *ip = vma->vm_private_data;

	kref_get(&ip->ref);
}

static void ipath_vma_close(struct vm_area_struct *vma)
{
	struct ipath_mmap_info *ip = vma->vm_private_data;

	kref_put(&ip->ref, ipath_release_mmap_info);
}

static const struct vm_operations_struct ipath_vm_ops = {
	.open =     ipath_vma_open,
	.close =    ipath_vma_close,
};

/**
 * ipath_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 ipath_mmap(struct ib_ucontext *context, struct vm_area_struct *vma)
{
	struct ipath_ibdev *dev = to_idev(context->device);
	unsigned long offset = vma->vm_pgoff << PAGE_SHIFT;
	unsigned long size = vma->vm_end - vma->vm_start;
	struct ipath_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 = &ipath_vm_ops;
		vma->vm_private_data = ip;
		ipath_vma_open(vma);
		goto done;
	}
	spin_unlock_irq(&dev->pending_lock);
done:
	return ret;
}

/*
 * Allocate information for ipath_mmap
 */
struct ipath_mmap_info *ipath_create_mmap_info(struct ipath_ibdev *dev,
					       u32 size,
					       struct ib_ucontext *context,
					       void *obj) {
	struct ipath_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 ipath_update_mmap_info(struct ipath_ibdev *dev,
			    struct ipath_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;
}
Commit	Line	Data
373d9915	1	/*
87427da5	2	* Copyright (c) 2006, 2007 QLogic Corporation. All rights reserved.
373d9915 RC	3	*
	4	* This software is available to you under a choice of one of two
	5	* licenses. You may choose to be licensed under the terms of the GNU
	6	* General Public License (GPL) Version 2, available from the file
	7	* COPYING in the main directory of this source tree, or the
	8	* OpenIB.org BSD license below:
	9	*
	10	* Redistribution and use in source and binary forms, with or
	11	* without modification, are permitted provided that the following
	12	* conditions are met:
	13	*
	14	* - Redistributions of source code must retain the above
	15	* copyright notice, this list of conditions and the following
	16	* disclaimer.
	17	*
	18	* - Redistributions in binary form must reproduce the above
	19	* copyright notice, this list of conditions and the following
	20	* disclaimer in the documentation and/or other materials
	21	* provided with the distribution.
	22	*
	23	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
	24	* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
	25	* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
	26	* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
	27	* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
	28	* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
	29	* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
	30	* SOFTWARE.
	31	*/
	32
373d9915 RC	33	#include <linux/module.h>
373d9915 RC	34	#include <linux/vmalloc.h>
5a0e3ad6	35	#include <linux/slab.h>
373d9915 RC	36	#include <linux/mm.h>
	37	#include <linux/errno.h>
	38	#include <asm/pgtable.h>
	39
	40	#include "ipath_verbs.h"
	41
	42	/**
	43	* ipath_release_mmap_info - free mmap info structure
	44	* @ref: a pointer to the kref within struct ipath_mmap_info
	45	*/
	46	void ipath_release_mmap_info(struct kref *ref)
	47	{
	48	struct ipath_mmap_info *ip =
	49	container_of(ref, struct ipath_mmap_info, ref);
6b66b2da RW	50	struct ipath_ibdev *dev = to_idev(ip->context->device);
	51
	52	spin_lock_irq(&dev->pending_lock);
	53	list_del(&ip->pending_mmaps);
	54	spin_unlock_irq(&dev->pending_lock);
373d9915 RC	55
	56	vfree(ip->obj);
	57	kfree(ip);
	58	}
	59
	60	/*
	61	* open and close keep track of how many times the CQ is mapped,
	62	* to avoid releasing it.
	63	*/
	64	static void ipath_vma_open(struct vm_area_struct *vma)
	65	{
	66	struct ipath_mmap_info *ip = vma->vm_private_data;
	67
	68	kref_get(&ip->ref);
373d9915 RC	69	}
	70
	71	static void ipath_vma_close(struct vm_area_struct *vma)
	72	{
	73	struct ipath_mmap_info *ip = vma->vm_private_data;
	74
373d9915 RC	75	kref_put(&ip->ref, ipath_release_mmap_info);
	76	}
	77
f0f37e2f	78	static const struct vm_operations_struct ipath_vm_ops = {
373d9915 RC	79	.open = ipath_vma_open,
	80	.close = ipath_vma_close,
	81	};
	82
	83	/**
	84	* ipath_mmap - create a new mmap region
	85	* @context: the IB user context of the process making the mmap() call
	86	* @vma: the VMA to be initialized
	87	* Return zero if the mmap is OK. Otherwise, return an errno.
	88	*/
	89	int ipath_mmap(struct ib_ucontext context, struct vm_area_struct vma)
	90	{
	91	struct ipath_ibdev *dev = to_idev(context->device);
	92	unsigned long offset = vma->vm_pgoff << PAGE_SHIFT;
	93	unsigned long size = vma->vm_end - vma->vm_start;
6b66b2da	94	struct ipath_mmap_info ip, pp;
373d9915 RC	95	int ret = -EINVAL;
	96
	97	/*
	98	* Search the device's list of objects waiting for a mmap call.
	99	* Normally, this list is very short since a call to create a
	100	* CQ, QP, or SRQ is soon followed by a call to mmap().
	101	*/
	102	spin_lock_irq(&dev->pending_lock);
6b66b2da RW	103	list_for_each_entry_safe(ip, pp, &dev->pending_mmaps,
6b66b2da RW	104	pending_mmaps) {
373d9915	105	/* Only the creator is allowed to mmap the object */
6b66b2da	106	if (context != ip->context \|\| (__u64) offset != ip->offset)
373d9915 RC	107	continue;
	108	/* Don't allow a mmap larger than the object. */
	109	if (size > ip->size)
	110	break;
	111
6b66b2da	112	list_del_init(&ip->pending_mmaps);
373d9915 RC	113	spin_unlock_irq(&dev->pending_lock);
	114
	115	ret = remap_vmalloc_range(vma, ip->obj, 0);
	116	if (ret)
	117	goto done;
	118	vma->vm_ops = &ipath_vm_ops;
	119	vma->vm_private_data = ip;
	120	ipath_vma_open(vma);
	121	goto done;
	122	}
	123	spin_unlock_irq(&dev->pending_lock);
	124	done:
	125	return ret;
	126	}
6b66b2da RW	127
	128	/*
	129	* Allocate information for ipath_mmap
	130	*/
	131	struct ipath_mmap_info ipath_create_mmap_info(struct ipath_ibdev dev,
	132	u32 size,
	133	struct ib_ucontext *context,
	134	void *obj) {
	135	struct ipath_mmap_info *ip;
	136
	137	ip = kmalloc(sizeof *ip, GFP_KERNEL);
	138	if (!ip)
	139	goto bail;
	140
	141	size = PAGE_ALIGN(size);
	142
	143	spin_lock_irq(&dev->mmap_offset_lock);
	144	if (dev->mmap_offset == 0)
	145	dev->mmap_offset = PAGE_SIZE;
	146	ip->offset = dev->mmap_offset;
	147	dev->mmap_offset += size;
	148	spin_unlock_irq(&dev->mmap_offset_lock);
	149
	150	INIT_LIST_HEAD(&ip->pending_mmaps);
	151	ip->size = size;
	152	ip->context = context;
	153	ip->obj = obj;
	154	kref_init(&ip->ref);
	155
	156	bail:
	157	return ip;
	158	}
	159
	160	void ipath_update_mmap_info(struct ipath_ibdev *dev,
	161	struct ipath_mmap_info *ip,
	162	u32 size, void *obj) {
	163	size = PAGE_ALIGN(size);
	164
	165	spin_lock_irq(&dev->mmap_offset_lock);
	166	if (dev->mmap_offset == 0)
	167	dev->mmap_offset = PAGE_SIZE;
	168	ip->offset = dev->mmap_offset;
	169	dev->mmap_offset += size;
	170	spin_unlock_irq(&dev->mmap_offset_lock);
	171
	172	ip->size = size;
	173	ip->obj = obj;
	174	}