drivers/net/ethernet/mellanox/mlx5/core/pagealloc.c - linux - Git at Google

 /*
  * Copyright (c) 2013, Mellanox Technologies inc.  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 <asm-generic/kmap_types.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/mlx5/driver.h>
 #include <linux/mlx5/cmd.h>
 #include "mlx5_core.h"

 enum {
 	MLX5_PAGES_CANT_GIVE	= 0,
 	MLX5_PAGES_GIVE		= 1,
 	MLX5_PAGES_TAKE		= 2
 };

 enum {
 	MLX5_BOOT_PAGES		= 1,
 	MLX5_INIT_PAGES		= 2,
 	MLX5_POST_INIT_PAGES	= 3
 };

 struct mlx5_pages_req {
 	struct mlx5_core_dev *dev;
 	u32	func_id;
 	s32	npages;
 	struct work_struct work;
 };

 struct fw_page {
 	struct rb_node	rb_node;
 	u64		addr;
 	struct page	*page;
 	u16		func_id;
 };

 struct mlx5_query_pages_inbox {
 	struct mlx5_inbox_hdr	hdr;
 	u8			rsvd[8];
 };

 struct mlx5_query_pages_outbox {
 	struct mlx5_outbox_hdr	hdr;
 	__be16			rsvd;
 	__be16			func_id;
 	__be32			num_pages;
 };

 struct mlx5_manage_pages_inbox {
 	struct mlx5_inbox_hdr	hdr;
 	__be16			rsvd;
 	__be16			func_id;
 	__be32			num_entries;
 	__be64			pas[0];
 };

 struct mlx5_manage_pages_outbox {
 	struct mlx5_outbox_hdr	hdr;
 	__be32			num_entries;
 	u8			rsvd[4];
 	__be64			pas[0];
 };

 enum {
 	MAX_RECLAIM_TIME_MSECS	= 5000,
 };

 static int insert_page(struct mlx5_core_dev *dev, u64 addr, struct page *page, u16 func_id)
 {
 	struct rb_root *root = &dev->priv.page_root;
 	struct rb_node **new = &root->rb_node;
 	struct rb_node *parent = NULL;
 	struct fw_page *nfp;
 	struct fw_page *tfp;

 	while (*new) {
 		parent = *new;
 		tfp = rb_entry(parent, struct fw_page, rb_node);
 		if (tfp->addr < addr)
 			new = &parent->rb_left;
 		else if (tfp->addr > addr)
 			new = &parent->rb_right;
 		else
 			return -EEXIST;
 	}

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

 	nfp->addr = addr;
 	nfp->page = page;
 	nfp->func_id = func_id;

 	rb_link_node(&nfp->rb_node, parent, new);
 	rb_insert_color(&nfp->rb_node, root);

 	return 0;
 }

 static struct page *remove_page(struct mlx5_core_dev *dev, u64 addr)
 {
 	struct rb_root *root = &dev->priv.page_root;
 	struct rb_node *tmp = root->rb_node;
 	struct page *result = NULL;
 	struct fw_page *tfp;

 	while (tmp) {
 		tfp = rb_entry(tmp, struct fw_page, rb_node);
 		if (tfp->addr < addr) {
 			tmp = tmp->rb_left;
 		} else if (tfp->addr > addr) {
 			tmp = tmp->rb_right;
 		} else {
 			rb_erase(&tfp->rb_node, root);
 			result = tfp->page;
 			kfree(tfp);
 			break;
 		}
 	}

 	return result;
 }

 static int mlx5_cmd_query_pages(struct mlx5_core_dev *dev, u16 *func_id,
 				s32 *npages, int boot)
 {
 	struct mlx5_query_pages_inbox	in;
 	struct mlx5_query_pages_outbox	out;
 	int err;

 	memset(&in, 0, sizeof(in));
 	memset(&out, 0, sizeof(out));
 	in.hdr.opcode = cpu_to_be16(MLX5_CMD_OP_QUERY_PAGES);
 	in.hdr.opmod = boot ? cpu_to_be16(MLX5_BOOT_PAGES) : cpu_to_be16(MLX5_INIT_PAGES);

 	err = mlx5_cmd_exec(dev, &in, sizeof(in), &out, sizeof(out));
 	if (err)
 		return err;

 	if (out.hdr.status)
 		return mlx5_cmd_status_to_err(&out.hdr);

 	*npages = be32_to_cpu(out.num_pages);
 	*func_id = be16_to_cpu(out.func_id);

 	return err;
 }

 static int give_pages(struct mlx5_core_dev *dev, u16 func_id, int npages,
 		      int notify_fail)
 {
 	struct mlx5_manage_pages_inbox *in;
 	struct mlx5_manage_pages_outbox out;
 	struct page *page;
 	int inlen;
 	u64 addr;
 	int err;
 	int i;

 	inlen = sizeof(*in) + npages * sizeof(in->pas[0]);
 	in = mlx5_vzalloc(inlen);
 	if (!in) {
 		mlx5_core_warn(dev, "vzalloc failed %d\n", inlen);
 		return -ENOMEM;
 	}
 	memset(&out, 0, sizeof(out));

 	for (i = 0; i < npages; i++) {
 		page = alloc_page(GFP_HIGHUSER);
 		if (!page) {
 			err = -ENOMEM;
 			mlx5_core_warn(dev, "failed to allocate page\n");
 			goto out_alloc;
 		}
 		addr = dma_map_page(&dev->pdev->dev, page, 0,
 				    PAGE_SIZE, DMA_BIDIRECTIONAL);
 		if (dma_mapping_error(&dev->pdev->dev, addr)) {
 			mlx5_core_warn(dev, "failed dma mapping page\n");
 			__free_page(page);
 			err = -ENOMEM;
 			goto out_alloc;
 		}
 		err = insert_page(dev, addr, page, func_id);
 		if (err) {
 			mlx5_core_err(dev, "failed to track allocated page\n");
 			dma_unmap_page(&dev->pdev->dev, addr, PAGE_SIZE, DMA_BIDIRECTIONAL);
 			__free_page(page);
 			err = -ENOMEM;
 			goto out_alloc;
 		}
 		in->pas[i] = cpu_to_be64(addr);
 	}

 	in->hdr.opcode = cpu_to_be16(MLX5_CMD_OP_MANAGE_PAGES);
 	in->hdr.opmod = cpu_to_be16(MLX5_PAGES_GIVE);
 	in->func_id = cpu_to_be16(func_id);
 	in->num_entries = cpu_to_be32(npages);
 	err = mlx5_cmd_exec(dev, in, inlen, &out, sizeof(out));
 	mlx5_core_dbg(dev, "err %d\n", err);
 	if (err) {
 		mlx5_core_warn(dev, "func_id 0x%x, npages %d, err %d\n", func_id, npages, err);
 		goto out_alloc;
 	}
 	dev->priv.fw_pages += npages;

 	if (out.hdr.status) {
 		err = mlx5_cmd_status_to_err(&out.hdr);
 		if (err) {
 			mlx5_core_warn(dev, "func_id 0x%x, npages %d, status %d\n", func_id, npages, out.hdr.status);
 			goto out_alloc;
 		}
 	}

 	mlx5_core_dbg(dev, "err %d\n", err);

 	goto out_free;

 out_alloc:
 	if (notify_fail) {
 		memset(in, 0, inlen);
 		memset(&out, 0, sizeof(out));
 		in->hdr.opcode = cpu_to_be16(MLX5_CMD_OP_MANAGE_PAGES);
 		in->hdr.opmod = cpu_to_be16(MLX5_PAGES_CANT_GIVE);
 		if (mlx5_cmd_exec(dev, in, sizeof(*in), &out, sizeof(out)))
 			mlx5_core_warn(dev, "\n");
 	}
 	for (i--; i >= 0; i--) {
 		addr = be64_to_cpu(in->pas[i]);
 		page = remove_page(dev, addr);
 		if (!page) {
 			mlx5_core_err(dev, "BUG: can't remove page at addr 0x%llx\n",
 				      addr);
 			continue;
 		}
 		dma_unmap_page(&dev->pdev->dev, addr, PAGE_SIZE, DMA_BIDIRECTIONAL);
 		__free_page(page);
 	}

 out_free:
 	mlx5_vfree(in);
 	return err;
 }

 static int reclaim_pages(struct mlx5_core_dev *dev, u32 func_id, int npages,
 			 int *nclaimed)
 {
 	struct mlx5_manage_pages_inbox   in;
 	struct mlx5_manage_pages_outbox *out;
 	struct page *page;
 	int num_claimed;
 	int outlen;
 	u64 addr;
 	int err;
 	int i;

 	if (nclaimed)
 		*nclaimed = 0;

 	memset(&in, 0, sizeof(in));
 	outlen = sizeof(*out) + npages * sizeof(out->pas[0]);
 	out = mlx5_vzalloc(outlen);
 	if (!out)
 		return -ENOMEM;

 	in.hdr.opcode = cpu_to_be16(MLX5_CMD_OP_MANAGE_PAGES);
 	in.hdr.opmod = cpu_to_be16(MLX5_PAGES_TAKE);
 	in.func_id = cpu_to_be16(func_id);
 	in.num_entries = cpu_to_be32(npages);
 	mlx5_core_dbg(dev, "npages %d, outlen %d\n", npages, outlen);
 	err = mlx5_cmd_exec(dev, &in, sizeof(in), out, outlen);
 	if (err) {
 		mlx5_core_err(dev, "failed recliaming pages\n");
 		goto out_free;
 	}
 	dev->priv.fw_pages -= npages;

 	if (out->hdr.status) {
 		err = mlx5_cmd_status_to_err(&out->hdr);
 		goto out_free;
 	}

 	num_claimed = be32_to_cpu(out->num_entries);
 	if (nclaimed)
 		*nclaimed = num_claimed;

 	for (i = 0; i < num_claimed; i++) {
 		addr = be64_to_cpu(out->pas[i]);
 		page = remove_page(dev, addr);
 		if (!page) {
 			mlx5_core_warn(dev, "FW reported unknown DMA address 0x%llx\n", addr);
 		} else {
 			dma_unmap_page(&dev->pdev->dev, addr, PAGE_SIZE, DMA_BIDIRECTIONAL);
 			__free_page(page);
 		}
 	}

 out_free:
 	mlx5_vfree(out);
 	return err;
 }

 static void pages_work_handler(struct work_struct *work)
 {
 	struct mlx5_pages_req *req = container_of(work, struct mlx5_pages_req, work);
 	struct mlx5_core_dev *dev = req->dev;
 	int err = 0;

 	if (req->npages < 0)
 		err = reclaim_pages(dev, req->func_id, -1 * req->npages, NULL);
 	else if (req->npages > 0)
 		err = give_pages(dev, req->func_id, req->npages, 1);

 	if (err)
 		mlx5_core_warn(dev, "%s fail %d\n", req->npages < 0 ?
 			       "reclaim" : "give", err);

 	kfree(req);
 }

 void mlx5_core_req_pages_handler(struct mlx5_core_dev *dev, u16 func_id,
 				 s32 npages)
 {
 	struct mlx5_pages_req *req;

 	req = kzalloc(sizeof(*req), GFP_ATOMIC);
 	if (!req) {
 		mlx5_core_warn(dev, "failed to allocate pages request\n");
 		return;
 	}

 	req->dev = dev;
 	req->func_id = func_id;
 	req->npages = npages;
 	INIT_WORK(&req->work, pages_work_handler);
 	queue_work(dev->priv.pg_wq, &req->work);
 }

 int mlx5_satisfy_startup_pages(struct mlx5_core_dev *dev, int boot)
 {
 	u16 uninitialized_var(func_id);
 	s32 uninitialized_var(npages);
 	int err;

 	err = mlx5_cmd_query_pages(dev, &func_id, &npages, boot);
 	if (err)
 		return err;

 	mlx5_core_dbg(dev, "requested %d %s pages for func_id 0x%x\n",
 		      npages, boot ? "boot" : "init", func_id);

 	return give_pages(dev, func_id, npages, 0);
 }

 static int optimal_reclaimed_pages(void)
 {
 	struct mlx5_cmd_prot_block *block;
 	struct mlx5_cmd_layout *lay;
 	int ret;

 	ret = (sizeof(lay->in) + sizeof(block->data) -
 	       sizeof(struct mlx5_manage_pages_outbox)) / 8;

 	return ret;
 }

 int mlx5_reclaim_startup_pages(struct mlx5_core_dev *dev)
 {
 	unsigned long end = jiffies + msecs_to_jiffies(MAX_RECLAIM_TIME_MSECS);
 	struct fw_page *fwp;
 	struct rb_node *p;
 	int nclaimed = 0;
 	int err;

 	do {
 		p = rb_first(&dev->priv.page_root);
 		if (p) {
 			fwp = rb_entry(p, struct fw_page, rb_node);
 			err = reclaim_pages(dev, fwp->func_id,
 					    optimal_reclaimed_pages(),
 					    &nclaimed);
 			if (err) {
 				mlx5_core_warn(dev, "failed reclaiming pages (%d)\n", err);
 				return err;
 			}
 			if (nclaimed)
 				end = jiffies + msecs_to_jiffies(MAX_RECLAIM_TIME_MSECS);
 		}
 		if (time_after(jiffies, end)) {
 			mlx5_core_warn(dev, "FW did not return all pages. giving up...\n");
 			break;
 		}
 	} while (p);

 	return 0;
 }

 void mlx5_pagealloc_init(struct mlx5_core_dev *dev)
 {
 	dev->priv.page_root = RB_ROOT;
 }

 void mlx5_pagealloc_cleanup(struct mlx5_core_dev *dev)
 {
 	/* nothing */
 }

 int mlx5_pagealloc_start(struct mlx5_core_dev *dev)
 {
 	dev->priv.pg_wq = create_singlethread_workqueue("mlx5_page_allocator");
 	if (!dev->priv.pg_wq)
 		return -ENOMEM;

 	return 0;
 }

 void mlx5_pagealloc_stop(struct mlx5_core_dev *dev)
 {
 	destroy_workqueue(dev->priv.pg_wq);
 }
	/*
	* Copyright (c) 2013, Mellanox Technologies inc. 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 <asm-generic/kmap_types.h>
	#include <linux/kernel.h>
	#include <linux/module.h>
	#include <linux/mlx5/driver.h>
	#include <linux/mlx5/cmd.h>
	#include "mlx5_core.h"

	enum {
	MLX5_PAGES_CANT_GIVE = 0,
	MLX5_PAGES_GIVE = 1,
	MLX5_PAGES_TAKE = 2
	};

	enum {
	MLX5_BOOT_PAGES = 1,
	MLX5_INIT_PAGES = 2,
	MLX5_POST_INIT_PAGES = 3
	};

	struct mlx5_pages_req {
	struct mlx5_core_dev *dev;
	u32 func_id;
	s32 npages;
	struct work_struct work;
	};

	struct fw_page {
	struct rb_node rb_node;
	u64 addr;
	struct page *page;
	u16 func_id;
	};

	struct mlx5_query_pages_inbox {
	struct mlx5_inbox_hdr hdr;
	u8 rsvd[8];
	};

	struct mlx5_query_pages_outbox {
	struct mlx5_outbox_hdr hdr;
	__be16 rsvd;
	__be16 func_id;
	__be32 num_pages;
	};

	struct mlx5_manage_pages_inbox {
	struct mlx5_inbox_hdr hdr;
	__be16 rsvd;
	__be16 func_id;
	__be32 num_entries;
	__be64 pas[0];
	};

	struct mlx5_manage_pages_outbox {
	struct mlx5_outbox_hdr hdr;
	__be32 num_entries;
	u8 rsvd[4];
	__be64 pas[0];
	};

	enum {
	MAX_RECLAIM_TIME_MSECS = 5000,
	};

	static int insert_page(struct mlx5_core_dev dev, u64 addr, struct page page, u16 func_id)
	{
	struct rb_root *root = &dev->priv.page_root;
	struct rb_node **new = &root->rb_node;
	struct rb_node *parent = NULL;
	struct fw_page *nfp;
	struct fw_page *tfp;

	while (*new) {
	parent = *new;
	tfp = rb_entry(parent, struct fw_page, rb_node);
	if (tfp->addr < addr)
	new = &parent->rb_left;
	else if (tfp->addr > addr)
	new = &parent->rb_right;
	else
	return -EEXIST;
	}

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

	nfp->addr = addr;
	nfp->page = page;
	nfp->func_id = func_id;

	rb_link_node(&nfp->rb_node, parent, new);
	rb_insert_color(&nfp->rb_node, root);

	return 0;
	}

	static struct page remove_page(struct mlx5_core_dev dev, u64 addr)
	{
	struct rb_root *root = &dev->priv.page_root;
	struct rb_node *tmp = root->rb_node;
	struct page *result = NULL;
	struct fw_page *tfp;

	while (tmp) {
	tfp = rb_entry(tmp, struct fw_page, rb_node);
	if (tfp->addr < addr) {
	tmp = tmp->rb_left;
	} else if (tfp->addr > addr) {
	tmp = tmp->rb_right;
	} else {
	rb_erase(&tfp->rb_node, root);
	result = tfp->page;
	kfree(tfp);
	break;
	}
	}

	return result;
	}

	static int mlx5_cmd_query_pages(struct mlx5_core_dev dev, u16 func_id,
	s32 *npages, int boot)
	{
	struct mlx5_query_pages_inbox in;
	struct mlx5_query_pages_outbox out;
	int err;

	memset(&in, 0, sizeof(in));
	memset(&out, 0, sizeof(out));
	in.hdr.opcode = cpu_to_be16(MLX5_CMD_OP_QUERY_PAGES);
	in.hdr.opmod = boot ? cpu_to_be16(MLX5_BOOT_PAGES) : cpu_to_be16(MLX5_INIT_PAGES);

	err = mlx5_cmd_exec(dev, &in, sizeof(in), &out, sizeof(out));
	if (err)
	return err;

	if (out.hdr.status)
	return mlx5_cmd_status_to_err(&out.hdr);

	*npages = be32_to_cpu(out.num_pages);
	*func_id = be16_to_cpu(out.func_id);

	return err;
	}

	static int give_pages(struct mlx5_core_dev *dev, u16 func_id, int npages,
	int notify_fail)
	{
	struct mlx5_manage_pages_inbox *in;
	struct mlx5_manage_pages_outbox out;
	struct page *page;
	int inlen;
	u64 addr;
	int err;
	int i;

	inlen = sizeof(in) + npages sizeof(in->pas[0]);
	in = mlx5_vzalloc(inlen);
	if (!in) {
	mlx5_core_warn(dev, "vzalloc failed %d\n", inlen);
	return -ENOMEM;
	}
	memset(&out, 0, sizeof(out));

	for (i = 0; i < npages; i++) {
	page = alloc_page(GFP_HIGHUSER);
	if (!page) {
	err = -ENOMEM;
	mlx5_core_warn(dev, "failed to allocate page\n");
	goto out_alloc;
	}
	addr = dma_map_page(&dev->pdev->dev, page, 0,
	PAGE_SIZE, DMA_BIDIRECTIONAL);
	if (dma_mapping_error(&dev->pdev->dev, addr)) {
	mlx5_core_warn(dev, "failed dma mapping page\n");
	__free_page(page);
	err = -ENOMEM;
	goto out_alloc;
	}
	err = insert_page(dev, addr, page, func_id);
	if (err) {
	mlx5_core_err(dev, "failed to track allocated page\n");
	dma_unmap_page(&dev->pdev->dev, addr, PAGE_SIZE, DMA_BIDIRECTIONAL);
	__free_page(page);
	err = -ENOMEM;
	goto out_alloc;
	}
	in->pas[i] = cpu_to_be64(addr);
	}

	in->hdr.opcode = cpu_to_be16(MLX5_CMD_OP_MANAGE_PAGES);
	in->hdr.opmod = cpu_to_be16(MLX5_PAGES_GIVE);
	in->func_id = cpu_to_be16(func_id);
	in->num_entries = cpu_to_be32(npages);
	err = mlx5_cmd_exec(dev, in, inlen, &out, sizeof(out));
	mlx5_core_dbg(dev, "err %d\n", err);
	if (err) {
	mlx5_core_warn(dev, "func_id 0x%x, npages %d, err %d\n", func_id, npages, err);
	goto out_alloc;
	}
	dev->priv.fw_pages += npages;

	if (out.hdr.status) {
	err = mlx5_cmd_status_to_err(&out.hdr);
	if (err) {
	mlx5_core_warn(dev, "func_id 0x%x, npages %d, status %d\n", func_id, npages, out.hdr.status);
	goto out_alloc;
	}
	}

	mlx5_core_dbg(dev, "err %d\n", err);

	goto out_free;

	out_alloc:
	if (notify_fail) {
	memset(in, 0, inlen);
	memset(&out, 0, sizeof(out));
	in->hdr.opcode = cpu_to_be16(MLX5_CMD_OP_MANAGE_PAGES);
	in->hdr.opmod = cpu_to_be16(MLX5_PAGES_CANT_GIVE);
	if (mlx5_cmd_exec(dev, in, sizeof(*in), &out, sizeof(out)))
	mlx5_core_warn(dev, "\n");
	}
	for (i--; i >= 0; i--) {
	addr = be64_to_cpu(in->pas[i]);
	page = remove_page(dev, addr);
	if (!page) {
	mlx5_core_err(dev, "BUG: can't remove page at addr 0x%llx\n",
	addr);
	continue;
	}
	dma_unmap_page(&dev->pdev->dev, addr, PAGE_SIZE, DMA_BIDIRECTIONAL);
	__free_page(page);
	}

	out_free:
	mlx5_vfree(in);
	return err;
	}

	static int reclaim_pages(struct mlx5_core_dev *dev, u32 func_id, int npages,
	int *nclaimed)
	{
	struct mlx5_manage_pages_inbox in;
	struct mlx5_manage_pages_outbox *out;
	struct page *page;
	int num_claimed;
	int outlen;
	u64 addr;
	int err;
	int i;

	if (nclaimed)
	*nclaimed = 0;

	memset(&in, 0, sizeof(in));
	outlen = sizeof(out) + npages sizeof(out->pas[0]);
	out = mlx5_vzalloc(outlen);
	if (!out)
	return -ENOMEM;

	in.hdr.opcode = cpu_to_be16(MLX5_CMD_OP_MANAGE_PAGES);
	in.hdr.opmod = cpu_to_be16(MLX5_PAGES_TAKE);
	in.func_id = cpu_to_be16(func_id);
	in.num_entries = cpu_to_be32(npages);
	mlx5_core_dbg(dev, "npages %d, outlen %d\n", npages, outlen);
	err = mlx5_cmd_exec(dev, &in, sizeof(in), out, outlen);
	if (err) {
	mlx5_core_err(dev, "failed recliaming pages\n");
	goto out_free;
	}
	dev->priv.fw_pages -= npages;

	if (out->hdr.status) {
	err = mlx5_cmd_status_to_err(&out->hdr);
	goto out_free;
	}

	num_claimed = be32_to_cpu(out->num_entries);
	if (nclaimed)
	*nclaimed = num_claimed;

	for (i = 0; i < num_claimed; i++) {
	addr = be64_to_cpu(out->pas[i]);
	page = remove_page(dev, addr);
	if (!page) {
	mlx5_core_warn(dev, "FW reported unknown DMA address 0x%llx\n", addr);
	} else {
	dma_unmap_page(&dev->pdev->dev, addr, PAGE_SIZE, DMA_BIDIRECTIONAL);
	__free_page(page);
	}
	}

	out_free:
	mlx5_vfree(out);
	return err;
	}

	static void pages_work_handler(struct work_struct *work)
	{
	struct mlx5_pages_req *req = container_of(work, struct mlx5_pages_req, work);
	struct mlx5_core_dev *dev = req->dev;
	int err = 0;

	if (req->npages < 0)
	err = reclaim_pages(dev, req->func_id, -1 * req->npages, NULL);
	else if (req->npages > 0)
	err = give_pages(dev, req->func_id, req->npages, 1);

	if (err)
	mlx5_core_warn(dev, "%s fail %d\n", req->npages < 0 ?
	"reclaim" : "give", err);

	kfree(req);
	}

	void mlx5_core_req_pages_handler(struct mlx5_core_dev *dev, u16 func_id,
	s32 npages)
	{
	struct mlx5_pages_req *req;

	req = kzalloc(sizeof(*req), GFP_ATOMIC);
	if (!req) {
	mlx5_core_warn(dev, "failed to allocate pages request\n");
	return;
	}

	req->dev = dev;
	req->func_id = func_id;
	req->npages = npages;
	INIT_WORK(&req->work, pages_work_handler);
	queue_work(dev->priv.pg_wq, &req->work);
	}

	int mlx5_satisfy_startup_pages(struct mlx5_core_dev *dev, int boot)
	{
	u16 uninitialized_var(func_id);
	s32 uninitialized_var(npages);
	int err;

	err = mlx5_cmd_query_pages(dev, &func_id, &npages, boot);
	if (err)
	return err;

	mlx5_core_dbg(dev, "requested %d %s pages for func_id 0x%x\n",
	npages, boot ? "boot" : "init", func_id);

	return give_pages(dev, func_id, npages, 0);
	}

	static int optimal_reclaimed_pages(void)
	{
	struct mlx5_cmd_prot_block *block;
	struct mlx5_cmd_layout *lay;
	int ret;

	ret = (sizeof(lay->in) + sizeof(block->data) -
	sizeof(struct mlx5_manage_pages_outbox)) / 8;

	return ret;
	}

	int mlx5_reclaim_startup_pages(struct mlx5_core_dev *dev)
	{
	unsigned long end = jiffies + msecs_to_jiffies(MAX_RECLAIM_TIME_MSECS);
	struct fw_page *fwp;
	struct rb_node *p;
	int nclaimed = 0;
	int err;

	do {
	p = rb_first(&dev->priv.page_root);
	if (p) {
	fwp = rb_entry(p, struct fw_page, rb_node);
	err = reclaim_pages(dev, fwp->func_id,
	optimal_reclaimed_pages(),
	&nclaimed);
	if (err) {
	mlx5_core_warn(dev, "failed reclaiming pages (%d)\n", err);
	return err;
	}
	if (nclaimed)
	end = jiffies + msecs_to_jiffies(MAX_RECLAIM_TIME_MSECS);
	}
	if (time_after(jiffies, end)) {
	mlx5_core_warn(dev, "FW did not return all pages. giving up...\n");
	break;
	}
	} while (p);

	return 0;
	}

	void mlx5_pagealloc_init(struct mlx5_core_dev *dev)
	{
	dev->priv.page_root = RB_ROOT;
	}

	void mlx5_pagealloc_cleanup(struct mlx5_core_dev *dev)
	{
	/* nothing */
	}

	int mlx5_pagealloc_start(struct mlx5_core_dev *dev)
	{
	dev->priv.pg_wq = create_singlethread_workqueue("mlx5_page_allocator");
	if (!dev->priv.pg_wq)
	return -ENOMEM;

	return 0;
	}

	void mlx5_pagealloc_stop(struct mlx5_core_dev *dev)
	{
	destroy_workqueue(dev->priv.pg_wq);
	}