net/rds/ib_fmr.c - linux - Git at Google

 /*
  * Copyright (c) 2016 Oracle.  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 "ib_mr.h"

 struct rds_ib_mr *rds_ib_alloc_fmr(struct rds_ib_device *rds_ibdev, int npages)
 {
 	struct rds_ib_mr_pool *pool;
 	struct rds_ib_mr *ibmr = NULL;
 	struct rds_ib_fmr *fmr;
 	int err = 0;

 	if (npages <= RDS_MR_8K_MSG_SIZE)
 		pool = rds_ibdev->mr_8k_pool;
 	else
 		pool = rds_ibdev->mr_1m_pool;

 	ibmr = rds_ib_try_reuse_ibmr(pool);
 	if (ibmr)
 		return ibmr;

 	ibmr = kzalloc_node(sizeof(*ibmr), GFP_KERNEL,
 			    rdsibdev_to_node(rds_ibdev));
 	if (!ibmr) {
 		err = -ENOMEM;
 		goto out_no_cigar;
 	}

 	fmr = &ibmr->u.fmr;
 	fmr->fmr = ib_alloc_fmr(rds_ibdev->pd,
 			(IB_ACCESS_LOCAL_WRITE |
 			 IB_ACCESS_REMOTE_READ |
 			 IB_ACCESS_REMOTE_WRITE |
 			 IB_ACCESS_REMOTE_ATOMIC),
 			&pool->fmr_attr);
 	if (IS_ERR(fmr->fmr)) {
 		err = PTR_ERR(fmr->fmr);
 		fmr->fmr = NULL;
 		pr_warn("RDS/IB: %s failed (err=%d)\n", __func__, err);
 		goto out_no_cigar;
 	}

 	ibmr->pool = pool;
 	if (pool->pool_type == RDS_IB_MR_8K_POOL)
 		rds_ib_stats_inc(s_ib_rdma_mr_8k_alloc);
 	else
 		rds_ib_stats_inc(s_ib_rdma_mr_1m_alloc);

 	return ibmr;

 out_no_cigar:
 	kfree(ibmr);
 	atomic_dec(&pool->item_count);

 	return ERR_PTR(err);
 }

 static int rds_ib_map_fmr(struct rds_ib_device *rds_ibdev,
 			  struct rds_ib_mr *ibmr, struct scatterlist *sg,
 			  unsigned int nents)
 {
 	struct ib_device *dev = rds_ibdev->dev;
 	struct rds_ib_fmr *fmr = &ibmr->u.fmr;
 	struct scatterlist *scat = sg;
 	u64 io_addr = 0;
 	u64 *dma_pages;
 	u32 len;
 	int page_cnt, sg_dma_len;
 	int i, j;
 	int ret;

 	sg_dma_len = ib_dma_map_sg(dev, sg, nents, DMA_BIDIRECTIONAL);
 	if (unlikely(!sg_dma_len)) {
 		pr_warn("RDS/IB: %s failed!\n", __func__);
 		return -EBUSY;
 	}

 	len = 0;
 	page_cnt = 0;

 	for (i = 0; i < sg_dma_len; ++i) {
 		unsigned int dma_len = sg_dma_len(&scat[i]);
 		u64 dma_addr = sg_dma_address(&scat[i]);

 		if (dma_addr & ~PAGE_MASK) {
 			if (i > 0) {
 				ib_dma_unmap_sg(dev, sg, nents,
 						DMA_BIDIRECTIONAL);
 				return -EINVAL;
 			} else {
 				++page_cnt;
 			}
 		}
 		if ((dma_addr + dma_len) & ~PAGE_MASK) {
 			if (i < sg_dma_len - 1) {
 				ib_dma_unmap_sg(dev, sg, nents,
 						DMA_BIDIRECTIONAL);
 				return -EINVAL;
 			} else {
 				++page_cnt;
 			}
 		}

 		len += dma_len;
 	}

 	page_cnt += len >> PAGE_SHIFT;
 	if (page_cnt > ibmr->pool->fmr_attr.max_pages) {
 		ib_dma_unmap_sg(dev, sg, nents, DMA_BIDIRECTIONAL);
 		return -EINVAL;
 	}

 	dma_pages = kmalloc_array_node(sizeof(u64), page_cnt, GFP_ATOMIC,
 				       rdsibdev_to_node(rds_ibdev));
 	if (!dma_pages) {
 		ib_dma_unmap_sg(dev, sg, nents, DMA_BIDIRECTIONAL);
 		return -ENOMEM;
 	}

 	page_cnt = 0;
 	for (i = 0; i < sg_dma_len; ++i) {
 		unsigned int dma_len = sg_dma_len(&scat[i]);
 		u64 dma_addr = sg_dma_address(&scat[i]);

 		for (j = 0; j < dma_len; j += PAGE_SIZE)
 			dma_pages[page_cnt++] =
 				(dma_addr & PAGE_MASK) + j;
 	}

 	ret = ib_map_phys_fmr(fmr->fmr, dma_pages, page_cnt, io_addr);
 	if (ret) {
 		ib_dma_unmap_sg(dev, sg, nents, DMA_BIDIRECTIONAL);
 		goto out;
 	}

 	/* Success - we successfully remapped the MR, so we can
 	 * safely tear down the old mapping.
 	 */
 	rds_ib_teardown_mr(ibmr);

 	ibmr->sg = scat;
 	ibmr->sg_len = nents;
 	ibmr->sg_dma_len = sg_dma_len;
 	ibmr->remap_count++;

 	if (ibmr->pool->pool_type == RDS_IB_MR_8K_POOL)
 		rds_ib_stats_inc(s_ib_rdma_mr_8k_used);
 	else
 		rds_ib_stats_inc(s_ib_rdma_mr_1m_used);
 	ret = 0;

 out:
 	kfree(dma_pages);

 	return ret;
 }

 struct rds_ib_mr *rds_ib_reg_fmr(struct rds_ib_device *rds_ibdev,
 				 struct scatterlist *sg,
 				 unsigned long nents,
 				 u32 *key)
 {
 	struct rds_ib_mr *ibmr = NULL;
 	struct rds_ib_fmr *fmr;
 	int ret;

 	ibmr = rds_ib_alloc_fmr(rds_ibdev, nents);
 	if (IS_ERR(ibmr))
 		return ibmr;

 	ibmr->device = rds_ibdev;
 	fmr = &ibmr->u.fmr;
 	ret = rds_ib_map_fmr(rds_ibdev, ibmr, sg, nents);
 	if (ret == 0)
 		*key = fmr->fmr->rkey;
 	else
 		rds_ib_free_mr(ibmr, 0);

 	return ibmr;
 }

 void rds_ib_unreg_fmr(struct list_head *list, unsigned int *nfreed,
 		      unsigned long *unpinned, unsigned int goal)
 {
 	struct rds_ib_mr *ibmr, *next;
 	struct rds_ib_fmr *fmr;
 	LIST_HEAD(fmr_list);
 	int ret = 0;
 	unsigned int freed = *nfreed;

 	/* String all ib_mr's onto one list and hand them to  ib_unmap_fmr */
 	list_for_each_entry(ibmr, list, unmap_list) {
 		fmr = &ibmr->u.fmr;
 		list_add(&fmr->fmr->list, &fmr_list);
 	}

 	ret = ib_unmap_fmr(&fmr_list);
 	if (ret)
 		pr_warn("RDS/IB: FMR invalidation failed (err=%d)\n", ret);

 	/* Now we can destroy the DMA mapping and unpin any pages */
 	list_for_each_entry_safe(ibmr, next, list, unmap_list) {
 		fmr = &ibmr->u.fmr;
 		*unpinned += ibmr->sg_len;
 		__rds_ib_teardown_mr(ibmr);
 		if (freed < goal ||
 		    ibmr->remap_count >= ibmr->pool->fmr_attr.max_maps) {
 			if (ibmr->pool->pool_type == RDS_IB_MR_8K_POOL)
 				rds_ib_stats_inc(s_ib_rdma_mr_8k_free);
 			else
 				rds_ib_stats_inc(s_ib_rdma_mr_1m_free);
 			list_del(&ibmr->unmap_list);
 			ib_dealloc_fmr(fmr->fmr);
 			kfree(ibmr);
 			freed++;
 		}
 	}
 	*nfreed = freed;
 }

 void rds_ib_free_fmr_list(struct rds_ib_mr *ibmr)
 {
 	struct rds_ib_mr_pool *pool = ibmr->pool;

 	if (ibmr->remap_count >= pool->fmr_attr.max_maps)
 		llist_add(&ibmr->llnode, &pool->drop_list);
 	else
 		llist_add(&ibmr->llnode, &pool->free_list);
 }
	/*
	* Copyright (c) 2016 Oracle. 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 "ib_mr.h"

	struct rds_ib_mr rds_ib_alloc_fmr(struct rds_ib_device rds_ibdev, int npages)
	{
	struct rds_ib_mr_pool *pool;
	struct rds_ib_mr *ibmr = NULL;
	struct rds_ib_fmr *fmr;
	int err = 0;

	if (npages <= RDS_MR_8K_MSG_SIZE)
	pool = rds_ibdev->mr_8k_pool;
	else
	pool = rds_ibdev->mr_1m_pool;

	ibmr = rds_ib_try_reuse_ibmr(pool);
	if (ibmr)
	return ibmr;

	ibmr = kzalloc_node(sizeof(*ibmr), GFP_KERNEL,
	rdsibdev_to_node(rds_ibdev));
	if (!ibmr) {
	err = -ENOMEM;
	goto out_no_cigar;
	}

	fmr = &ibmr->u.fmr;
	fmr->fmr = ib_alloc_fmr(rds_ibdev->pd,
	(IB_ACCESS_LOCAL_WRITE \|
	IB_ACCESS_REMOTE_READ \|
	IB_ACCESS_REMOTE_WRITE \|
	IB_ACCESS_REMOTE_ATOMIC),
	&pool->fmr_attr);
	if (IS_ERR(fmr->fmr)) {
	err = PTR_ERR(fmr->fmr);
	fmr->fmr = NULL;
	pr_warn("RDS/IB: %s failed (err=%d)\n", __func__, err);
	goto out_no_cigar;
	}

	ibmr->pool = pool;
	if (pool->pool_type == RDS_IB_MR_8K_POOL)
	rds_ib_stats_inc(s_ib_rdma_mr_8k_alloc);
	else
	rds_ib_stats_inc(s_ib_rdma_mr_1m_alloc);

	return ibmr;

	out_no_cigar:
	kfree(ibmr);
	atomic_dec(&pool->item_count);

	return ERR_PTR(err);
	}

	static int rds_ib_map_fmr(struct rds_ib_device *rds_ibdev,
	struct rds_ib_mr ibmr, struct scatterlist sg,
	unsigned int nents)
	{
	struct ib_device *dev = rds_ibdev->dev;
	struct rds_ib_fmr *fmr = &ibmr->u.fmr;
	struct scatterlist *scat = sg;
	u64 io_addr = 0;
	u64 *dma_pages;
	u32 len;
	int page_cnt, sg_dma_len;
	int i, j;
	int ret;

	sg_dma_len = ib_dma_map_sg(dev, sg, nents, DMA_BIDIRECTIONAL);
	if (unlikely(!sg_dma_len)) {
	pr_warn("RDS/IB: %s failed!\n", __func__);
	return -EBUSY;
	}

	len = 0;
	page_cnt = 0;

	for (i = 0; i < sg_dma_len; ++i) {
	unsigned int dma_len = sg_dma_len(&scat[i]);
	u64 dma_addr = sg_dma_address(&scat[i]);

	if (dma_addr & ~PAGE_MASK) {
	if (i > 0) {
	ib_dma_unmap_sg(dev, sg, nents,
	DMA_BIDIRECTIONAL);
	return -EINVAL;
	} else {
	++page_cnt;
	}
	}
	if ((dma_addr + dma_len) & ~PAGE_MASK) {
	if (i < sg_dma_len - 1) {
	ib_dma_unmap_sg(dev, sg, nents,
	DMA_BIDIRECTIONAL);
	return -EINVAL;
	} else {
	++page_cnt;
	}
	}

	len += dma_len;
	}

	page_cnt += len >> PAGE_SHIFT;
	if (page_cnt > ibmr->pool->fmr_attr.max_pages) {
	ib_dma_unmap_sg(dev, sg, nents, DMA_BIDIRECTIONAL);
	return -EINVAL;
	}

	dma_pages = kmalloc_array_node(sizeof(u64), page_cnt, GFP_ATOMIC,
	rdsibdev_to_node(rds_ibdev));
	if (!dma_pages) {
	ib_dma_unmap_sg(dev, sg, nents, DMA_BIDIRECTIONAL);
	return -ENOMEM;
	}

	page_cnt = 0;
	for (i = 0; i < sg_dma_len; ++i) {
	unsigned int dma_len = sg_dma_len(&scat[i]);
	u64 dma_addr = sg_dma_address(&scat[i]);

	for (j = 0; j < dma_len; j += PAGE_SIZE)
	dma_pages[page_cnt++] =
	(dma_addr & PAGE_MASK) + j;
	}

	ret = ib_map_phys_fmr(fmr->fmr, dma_pages, page_cnt, io_addr);
	if (ret) {
	ib_dma_unmap_sg(dev, sg, nents, DMA_BIDIRECTIONAL);
	goto out;
	}

	/* Success - we successfully remapped the MR, so we can
	* safely tear down the old mapping.
	*/
	rds_ib_teardown_mr(ibmr);

	ibmr->sg = scat;
	ibmr->sg_len = nents;
	ibmr->sg_dma_len = sg_dma_len;
	ibmr->remap_count++;

	if (ibmr->pool->pool_type == RDS_IB_MR_8K_POOL)
	rds_ib_stats_inc(s_ib_rdma_mr_8k_used);
	else
	rds_ib_stats_inc(s_ib_rdma_mr_1m_used);
	ret = 0;

	out:
	kfree(dma_pages);

	return ret;
	}

	struct rds_ib_mr rds_ib_reg_fmr(struct rds_ib_device rds_ibdev,
	struct scatterlist *sg,
	unsigned long nents,
	u32 *key)
	{
	struct rds_ib_mr *ibmr = NULL;
	struct rds_ib_fmr *fmr;
	int ret;

	ibmr = rds_ib_alloc_fmr(rds_ibdev, nents);
	if (IS_ERR(ibmr))
	return ibmr;

	ibmr->device = rds_ibdev;
	fmr = &ibmr->u.fmr;
	ret = rds_ib_map_fmr(rds_ibdev, ibmr, sg, nents);
	if (ret == 0)
	*key = fmr->fmr->rkey;
	else
	rds_ib_free_mr(ibmr, 0);

	return ibmr;
	}

	void rds_ib_unreg_fmr(struct list_head list, unsigned int nfreed,
	unsigned long *unpinned, unsigned int goal)
	{
	struct rds_ib_mr ibmr, next;
	struct rds_ib_fmr *fmr;
	LIST_HEAD(fmr_list);
	int ret = 0;
	unsigned int freed = *nfreed;

	/* String all ib_mr's onto one list and hand them to ib_unmap_fmr */
	list_for_each_entry(ibmr, list, unmap_list) {
	fmr = &ibmr->u.fmr;
	list_add(&fmr->fmr->list, &fmr_list);
	}

	ret = ib_unmap_fmr(&fmr_list);
	if (ret)
	pr_warn("RDS/IB: FMR invalidation failed (err=%d)\n", ret);

	/* Now we can destroy the DMA mapping and unpin any pages */
	list_for_each_entry_safe(ibmr, next, list, unmap_list) {
	fmr = &ibmr->u.fmr;
	*unpinned += ibmr->sg_len;
	__rds_ib_teardown_mr(ibmr);
	if (freed < goal \|\|
	ibmr->remap_count >= ibmr->pool->fmr_attr.max_maps) {
	if (ibmr->pool->pool_type == RDS_IB_MR_8K_POOL)
	rds_ib_stats_inc(s_ib_rdma_mr_8k_free);
	else
	rds_ib_stats_inc(s_ib_rdma_mr_1m_free);
	list_del(&ibmr->unmap_list);
	ib_dealloc_fmr(fmr->fmr);
	kfree(ibmr);
	freed++;
	}
	}
	*nfreed = freed;
	}

	void rds_ib_free_fmr_list(struct rds_ib_mr *ibmr)
	{
	struct rds_ib_mr_pool *pool = ibmr->pool;

	if (ibmr->remap_count >= pool->fmr_attr.max_maps)
	llist_add(&ibmr->llnode, &pool->drop_list);
	else
	llist_add(&ibmr->llnode, &pool->free_list);
	}