drivers/infiniband/hw/mthca/mthca_allocator.c - kernel/prism - Git at Google

 /*
  * Copyright (c) 2004 Topspin Communications.  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/errno.h>
 #include <linux/slab.h>
 #include <linux/bitmap.h>

 #include "mthca_dev.h"

 /* Trivial bitmap-based allocator */
 u32 mthca_alloc(struct mthca_alloc *alloc)
 {
 	unsigned long flags;
 	u32 obj;

 	spin_lock_irqsave(&alloc->lock, flags);

 	obj = find_next_zero_bit(alloc->table, alloc->max, alloc->last);
 	if (obj >= alloc->max) {
 		alloc->top = (alloc->top + alloc->max) & alloc->mask;
 		obj = find_first_zero_bit(alloc->table, alloc->max);
 	}

 	if (obj < alloc->max) {
 		set_bit(obj, alloc->table);
 		obj |= alloc->top;
 	} else
 		obj = -1;

 	spin_unlock_irqrestore(&alloc->lock, flags);

 	return obj;
 }

 void mthca_free(struct mthca_alloc *alloc, u32 obj)
 {
 	unsigned long flags;

 	obj &= alloc->max - 1;

 	spin_lock_irqsave(&alloc->lock, flags);

 	clear_bit(obj, alloc->table);
 	alloc->last = min(alloc->last, obj);
 	alloc->top = (alloc->top + alloc->max) & alloc->mask;

 	spin_unlock_irqrestore(&alloc->lock, flags);
 }

 int mthca_alloc_init(struct mthca_alloc *alloc, u32 num, u32 mask,
 		     u32 reserved)
 {
 	int i;

 	/* num must be a power of 2 */
 	if (num != 1 << (ffs(num) - 1))
 		return -EINVAL;

 	alloc->last = 0;
 	alloc->top  = 0;
 	alloc->max  = num;
 	alloc->mask = mask;
 	spin_lock_init(&alloc->lock);
 	alloc->table = kmalloc(BITS_TO_LONGS(num) * sizeof (long),
 			       GFP_KERNEL);
 	if (!alloc->table)
 		return -ENOMEM;

 	bitmap_zero(alloc->table, num);
 	for (i = 0; i < reserved; ++i)
 		set_bit(i, alloc->table);

 	return 0;
 }

 void mthca_alloc_cleanup(struct mthca_alloc *alloc)
 {
 	kfree(alloc->table);
 }

 /*
  * Array of pointers with lazy allocation of leaf pages.  Callers of
  * _get, _set and _clear methods must use a lock or otherwise
  * serialize access to the array.
  */

 #define MTHCA_ARRAY_MASK (PAGE_SIZE / sizeof (void *) - 1)

 void *mthca_array_get(struct mthca_array *array, int index)
 {
 	int p = (index * sizeof (void *)) >> PAGE_SHIFT;

 	if (array->page_list[p].page)
 		return array->page_list[p].page[index & MTHCA_ARRAY_MASK];
 	else
 		return NULL;
 }

 int mthca_array_set(struct mthca_array *array, int index, void *value)
 {
 	int p = (index * sizeof (void *)) >> PAGE_SHIFT;

 	/* Allocate with GFP_ATOMIC because we'll be called with locks held. */
 	if (!array->page_list[p].page)
 		array->page_list[p].page = (void **) get_zeroed_page(GFP_ATOMIC);

 	if (!array->page_list[p].page)
 		return -ENOMEM;

 	array->page_list[p].page[index & MTHCA_ARRAY_MASK] = value;
 	++array->page_list[p].used;

 	return 0;
 }

 void mthca_array_clear(struct mthca_array *array, int index)
 {
 	int p = (index * sizeof (void *)) >> PAGE_SHIFT;

 	if (--array->page_list[p].used == 0) {
 		free_page((unsigned long) array->page_list[p].page);
 		array->page_list[p].page = NULL;
 	} else
 		array->page_list[p].page[index & MTHCA_ARRAY_MASK] = NULL;

 	if (array->page_list[p].used < 0)
 		pr_debug("Array %p index %d page %d with ref count %d < 0\n",
 			 array, index, p, array->page_list[p].used);
 }

 int mthca_array_init(struct mthca_array *array, int nent)
 {
 	int npage = (nent * sizeof (void *) + PAGE_SIZE - 1) / PAGE_SIZE;
 	int i;

 	array->page_list = kmalloc(npage * sizeof *array->page_list, GFP_KERNEL);
 	if (!array->page_list)
 		return -ENOMEM;

 	for (i = 0; i < npage; ++i) {
 		array->page_list[i].page = NULL;
 		array->page_list[i].used = 0;
 	}

 	return 0;
 }

 void mthca_array_cleanup(struct mthca_array *array, int nent)
 {
 	int i;

 	for (i = 0; i < (nent * sizeof (void *) + PAGE_SIZE - 1) / PAGE_SIZE; ++i)
 		free_page((unsigned long) array->page_list[i].page);

 	kfree(array->page_list);
 }

 /*
  * Handling for queue buffers -- we allocate a bunch of memory and
  * register it in a memory region at HCA virtual address 0.  If the
  * requested size is > max_direct, we split the allocation into
  * multiple pages, so we don't require too much contiguous memory.
  */

 int mthca_buf_alloc(struct mthca_dev *dev, int size, int max_direct,
 		    union mthca_buf *buf, int *is_direct, struct mthca_pd *pd,
 		    int hca_write, struct mthca_mr *mr)
 {
 	int err = -ENOMEM;
 	int npages, shift;
 	u64 *dma_list = NULL;
 	dma_addr_t t;
 	int i;

 	if (size <= max_direct) {
 		*is_direct = 1;
 		npages     = 1;
 		shift      = get_order(size) + PAGE_SHIFT;

 		buf->direct.buf = dma_alloc_coherent(&dev->pdev->dev,
 						     size, &t, GFP_KERNEL);
 		if (!buf->direct.buf)
 			return -ENOMEM;

 		pci_unmap_addr_set(&buf->direct, mapping, t);

 		memset(buf->direct.buf, 0, size);

 		while (t & ((1 << shift) - 1)) {
 			--shift;
 			npages *= 2;
 		}

 		dma_list = kmalloc(npages * sizeof *dma_list, GFP_KERNEL);
 		if (!dma_list)
 			goto err_free;

 		for (i = 0; i < npages; ++i)
 			dma_list[i] = t + i * (1 << shift);
 	} else {
 		*is_direct = 0;
 		npages     = (size + PAGE_SIZE - 1) / PAGE_SIZE;
 		shift      = PAGE_SHIFT;

 		dma_list = kmalloc(npages * sizeof *dma_list, GFP_KERNEL);
 		if (!dma_list)
 			return -ENOMEM;

 		buf->page_list = kmalloc(npages * sizeof *buf->page_list,
 					 GFP_KERNEL);
 		if (!buf->page_list)
 			goto err_out;

 		for (i = 0; i < npages; ++i)
 			buf->page_list[i].buf = NULL;

 		for (i = 0; i < npages; ++i) {
 			buf->page_list[i].buf =
 				dma_alloc_coherent(&dev->pdev->dev, PAGE_SIZE,
 						   &t, GFP_KERNEL);
 			if (!buf->page_list[i].buf)
 				goto err_free;

 			dma_list[i] = t;
 			pci_unmap_addr_set(&buf->page_list[i], mapping, t);

 			clear_page(buf->page_list[i].buf);
 		}
 	}

 	err = mthca_mr_alloc_phys(dev, pd->pd_num,
 				  dma_list, shift, npages,
 				  0, size,
 				  MTHCA_MPT_FLAG_LOCAL_READ |
 				  (hca_write ? MTHCA_MPT_FLAG_LOCAL_WRITE : 0),
 				  mr);
 	if (err)
 		goto err_free;

 	kfree(dma_list);

 	return 0;

 err_free:
 	mthca_buf_free(dev, size, buf, *is_direct, NULL);

 err_out:
 	kfree(dma_list);

 	return err;
 }

 void mthca_buf_free(struct mthca_dev *dev, int size, union mthca_buf *buf,
 		    int is_direct, struct mthca_mr *mr)
 {
 	int i;

 	if (mr)
 		mthca_free_mr(dev, mr);

 	if (is_direct)
 		dma_free_coherent(&dev->pdev->dev, size, buf->direct.buf,
 				  pci_unmap_addr(&buf->direct, mapping));
 	else {
 		for (i = 0; i < (size + PAGE_SIZE - 1) / PAGE_SIZE; ++i)
 			dma_free_coherent(&dev->pdev->dev, PAGE_SIZE,
 					  buf->page_list[i].buf,
 					  pci_unmap_addr(&buf->page_list[i],
 							 mapping));
 		kfree(buf->page_list);
 	}
 }
	/*
	* Copyright (c) 2004 Topspin Communications. 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/errno.h>
	#include <linux/slab.h>
	#include <linux/bitmap.h>

	#include "mthca_dev.h"

	/* Trivial bitmap-based allocator */
	u32 mthca_alloc(struct mthca_alloc *alloc)
	{
	unsigned long flags;
	u32 obj;

	spin_lock_irqsave(&alloc->lock, flags);

	obj = find_next_zero_bit(alloc->table, alloc->max, alloc->last);
	if (obj >= alloc->max) {
	alloc->top = (alloc->top + alloc->max) & alloc->mask;
	obj = find_first_zero_bit(alloc->table, alloc->max);
	}

	if (obj < alloc->max) {
	set_bit(obj, alloc->table);
	obj \|= alloc->top;
	} else
	obj = -1;

	spin_unlock_irqrestore(&alloc->lock, flags);

	return obj;
	}

	void mthca_free(struct mthca_alloc *alloc, u32 obj)
	{
	unsigned long flags;

	obj &= alloc->max - 1;

	spin_lock_irqsave(&alloc->lock, flags);

	clear_bit(obj, alloc->table);
	alloc->last = min(alloc->last, obj);
	alloc->top = (alloc->top + alloc->max) & alloc->mask;

	spin_unlock_irqrestore(&alloc->lock, flags);
	}

	int mthca_alloc_init(struct mthca_alloc *alloc, u32 num, u32 mask,
	u32 reserved)
	{
	int i;

	/* num must be a power of 2 */
	if (num != 1 << (ffs(num) - 1))
	return -EINVAL;

	alloc->last = 0;
	alloc->top = 0;
	alloc->max = num;
	alloc->mask = mask;
	spin_lock_init(&alloc->lock);
	alloc->table = kmalloc(BITS_TO_LONGS(num) * sizeof (long),
	GFP_KERNEL);
	if (!alloc->table)
	return -ENOMEM;

	bitmap_zero(alloc->table, num);
	for (i = 0; i < reserved; ++i)
	set_bit(i, alloc->table);

	return 0;
	}

	void mthca_alloc_cleanup(struct mthca_alloc *alloc)
	{
	kfree(alloc->table);
	}

	/*
	* Array of pointers with lazy allocation of leaf pages. Callers of
	* _get, _set and _clear methods must use a lock or otherwise
	* serialize access to the array.
	*/

	#define MTHCA_ARRAY_MASK (PAGE_SIZE / sizeof (void *) - 1)

	void mthca_array_get(struct mthca_array array, int index)
	{
	int p = (index * sizeof (void *)) >> PAGE_SHIFT;

	if (array->page_list[p].page)
	return array->page_list[p].page[index & MTHCA_ARRAY_MASK];
	else
	return NULL;
	}

	int mthca_array_set(struct mthca_array array, int index, void value)
	{
	int p = (index * sizeof (void *)) >> PAGE_SHIFT;

	/* Allocate with GFP_ATOMIC because we'll be called with locks held. */
	if (!array->page_list[p].page)
	array->page_list[p].page = (void **) get_zeroed_page(GFP_ATOMIC);

	if (!array->page_list[p].page)
	return -ENOMEM;

	array->page_list[p].page[index & MTHCA_ARRAY_MASK] = value;
	++array->page_list[p].used;

	return 0;
	}

	void mthca_array_clear(struct mthca_array *array, int index)
	{
	int p = (index * sizeof (void *)) >> PAGE_SHIFT;

	if (--array->page_list[p].used == 0) {
	free_page((unsigned long) array->page_list[p].page);
	array->page_list[p].page = NULL;
	} else
	array->page_list[p].page[index & MTHCA_ARRAY_MASK] = NULL;

	if (array->page_list[p].used < 0)
	pr_debug("Array %p index %d page %d with ref count %d < 0\n",
	array, index, p, array->page_list[p].used);
	}

	int mthca_array_init(struct mthca_array *array, int nent)
	{
	int npage = (nent * sizeof (void *) + PAGE_SIZE - 1) / PAGE_SIZE;
	int i;

	array->page_list = kmalloc(npage * sizeof *array->page_list, GFP_KERNEL);
	if (!array->page_list)
	return -ENOMEM;

	for (i = 0; i < npage; ++i) {
	array->page_list[i].page = NULL;
	array->page_list[i].used = 0;
	}

	return 0;
	}

	void mthca_array_cleanup(struct mthca_array *array, int nent)
	{
	int i;

	for (i = 0; i < (nent * sizeof (void *) + PAGE_SIZE - 1) / PAGE_SIZE; ++i)
	free_page((unsigned long) array->page_list[i].page);

	kfree(array->page_list);
	}

	/*
	* Handling for queue buffers -- we allocate a bunch of memory and
	* register it in a memory region at HCA virtual address 0. If the
	* requested size is > max_direct, we split the allocation into
	* multiple pages, so we don't require too much contiguous memory.
	*/

	int mthca_buf_alloc(struct mthca_dev *dev, int size, int max_direct,
	union mthca_buf buf, int is_direct, struct mthca_pd *pd,
	int hca_write, struct mthca_mr *mr)
	{
	int err = -ENOMEM;
	int npages, shift;
	u64 *dma_list = NULL;
	dma_addr_t t;
	int i;

	if (size <= max_direct) {
	*is_direct = 1;
	npages = 1;
	shift = get_order(size) + PAGE_SHIFT;

	buf->direct.buf = dma_alloc_coherent(&dev->pdev->dev,
	size, &t, GFP_KERNEL);
	if (!buf->direct.buf)
	return -ENOMEM;

	pci_unmap_addr_set(&buf->direct, mapping, t);

	memset(buf->direct.buf, 0, size);

	while (t & ((1 << shift) - 1)) {
	--shift;
	npages *= 2;
	}

	dma_list = kmalloc(npages * sizeof *dma_list, GFP_KERNEL);
	if (!dma_list)
	goto err_free;

	for (i = 0; i < npages; ++i)
	dma_list[i] = t + i * (1 << shift);
	} else {
	*is_direct = 0;
	npages = (size + PAGE_SIZE - 1) / PAGE_SIZE;
	shift = PAGE_SHIFT;

	dma_list = kmalloc(npages * sizeof *dma_list, GFP_KERNEL);
	if (!dma_list)
	return -ENOMEM;

	buf->page_list = kmalloc(npages * sizeof *buf->page_list,
	GFP_KERNEL);
	if (!buf->page_list)
	goto err_out;

	for (i = 0; i < npages; ++i)
	buf->page_list[i].buf = NULL;

	for (i = 0; i < npages; ++i) {
	buf->page_list[i].buf =
	dma_alloc_coherent(&dev->pdev->dev, PAGE_SIZE,
	&t, GFP_KERNEL);
	if (!buf->page_list[i].buf)
	goto err_free;

	dma_list[i] = t;
	pci_unmap_addr_set(&buf->page_list[i], mapping, t);

	clear_page(buf->page_list[i].buf);
	}
	}

	err = mthca_mr_alloc_phys(dev, pd->pd_num,
	dma_list, shift, npages,
	0, size,
	MTHCA_MPT_FLAG_LOCAL_READ \|
	(hca_write ? MTHCA_MPT_FLAG_LOCAL_WRITE : 0),
	mr);
	if (err)
	goto err_free;

	kfree(dma_list);

	return 0;

	err_free:
	mthca_buf_free(dev, size, buf, *is_direct, NULL);

	err_out:
	kfree(dma_list);

	return err;
	}

	void mthca_buf_free(struct mthca_dev dev, int size, union mthca_buf buf,
	int is_direct, struct mthca_mr *mr)
	{
	int i;

	if (mr)
	mthca_free_mr(dev, mr);

	if (is_direct)
	dma_free_coherent(&dev->pdev->dev, size, buf->direct.buf,
	pci_unmap_addr(&buf->direct, mapping));
	else {
	for (i = 0; i < (size + PAGE_SIZE - 1) / PAGE_SIZE; ++i)
	dma_free_coherent(&dev->pdev->dev, PAGE_SIZE,
	buf->page_list[i].buf,
	pci_unmap_addr(&buf->page_list[i],
	mapping));
	kfree(buf->page_list);
	}
	}