i40iw: add pble resource files

i40iw_pble.[ch] to manage pble resource for iwarp clients.

Changes since v2:
        remove unnecessary casts
Acked-by: Anjali Singhai Jain <anjali.singhai@intel.com>
Acked-by: Shannon Nelson <shannon.nelson@intel.com>
Signed-off-by: Faisal Latif <faisal.latif@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

drivers/infiniband/hw/i40iw/i40iw_pble.c

+/*******************************************************************************
+*
+* Copyright (c) 2015-2016 Intel 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
+* OpenFabrics.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 "i40iw_status.h"
+#include "i40iw_osdep.h"
+#include "i40iw_register.h"
+#include "i40iw_hmc.h"
+
+#include "i40iw_d.h"
+#include "i40iw_type.h"
+#include "i40iw_p.h"
+
+#include <linux/pci.h>
+#include <linux/genalloc.h>
+#include <linux/vmalloc.h>
+#include "i40iw_pble.h"
+#include "i40iw.h"
+
+struct i40iw_device;
+static enum i40iw_status_code add_pble_pool(struct i40iw_sc_dev *dev,
+					    struct i40iw_hmc_pble_rsrc *pble_rsrc);
+static void i40iw_free_vmalloc_mem(struct i40iw_hw *hw, struct i40iw_chunk *chunk);
+
+/**
+ * i40iw_destroy_pble_pool - destroy pool during module unload
+ * @pble_rsrc:	pble resources
+ */
+void i40iw_destroy_pble_pool(struct i40iw_sc_dev *dev, struct i40iw_hmc_pble_rsrc *pble_rsrc)
+{
+	struct list_head *clist;
+	struct list_head *tlist;
+	struct i40iw_chunk *chunk;
+	struct i40iw_pble_pool *pinfo = &pble_rsrc->pinfo;
+
+	if (pinfo->pool) {
+		list_for_each_safe(clist, tlist, &pinfo->clist) {
+			chunk = list_entry(clist, struct i40iw_chunk, list);
+			if (chunk->type == I40IW_VMALLOC)
+				i40iw_free_vmalloc_mem(dev->hw, chunk);
+			kfree(chunk);
+		}
+		gen_pool_destroy(pinfo->pool);
+	}
+}
+
+/**
+ * i40iw_hmc_init_pble - Initialize pble resources during module load
+ * @dev: i40iw_sc_dev struct
+ * @pble_rsrc:	pble resources
+ */
+enum i40iw_status_code i40iw_hmc_init_pble(struct i40iw_sc_dev *dev,
+					   struct i40iw_hmc_pble_rsrc *pble_rsrc)
+{
+	struct i40iw_hmc_info *hmc_info;
+	u32 fpm_idx = 0;
+
+	hmc_info = dev->hmc_info;
+	pble_rsrc->fpm_base_addr = hmc_info->hmc_obj[I40IW_HMC_IW_PBLE].base;
+	/* Now start the pble' on 4k boundary */
+	if (pble_rsrc->fpm_base_addr & 0xfff)
+		fpm_idx = (PAGE_SIZE - (pble_rsrc->fpm_base_addr & 0xfff)) >> 3;
+
+	pble_rsrc->unallocated_pble =
+	    hmc_info->hmc_obj[I40IW_HMC_IW_PBLE].cnt - fpm_idx;
+	pble_rsrc->next_fpm_addr = pble_rsrc->fpm_base_addr + (fpm_idx << 3);
+
+	pble_rsrc->pinfo.pool_shift = POOL_SHIFT;
+	pble_rsrc->pinfo.pool = gen_pool_create(pble_rsrc->pinfo.pool_shift, -1);
+	INIT_LIST_HEAD(&pble_rsrc->pinfo.clist);
+	if (!pble_rsrc->pinfo.pool)
+		goto error;
+
+	if (add_pble_pool(dev, pble_rsrc))
+		goto error;
+
+	return 0;
+
+ error:i40iw_destroy_pble_pool(dev, pble_rsrc);
+	return I40IW_ERR_NO_MEMORY;
+}
+
+/**
+ * get_sd_pd_idx -  Returns sd index, pd index and rel_pd_idx from fpm address
+ * @ pble_rsrc:	structure containing fpm address
+ * @ idx: where to return indexes
+ */
+static inline void get_sd_pd_idx(struct i40iw_hmc_pble_rsrc *pble_rsrc,
+				 struct sd_pd_idx *idx)
+{
+	idx->sd_idx = (u32)(pble_rsrc->next_fpm_addr) / I40IW_HMC_DIRECT_BP_SIZE;
+	idx->pd_idx = (u32)(pble_rsrc->next_fpm_addr) / I40IW_HMC_PAGED_BP_SIZE;
+	idx->rel_pd_idx = (idx->pd_idx % I40IW_HMC_PD_CNT_IN_SD);
+}
+
+/**
+ * add_sd_direct - add sd direct for pble
+ * @dev: hardware control device structure
+ * @pble_rsrc: pble resource ptr
+ * @info: page info for sd
+ */
+static enum i40iw_status_code add_sd_direct(struct i40iw_sc_dev *dev,
+					    struct i40iw_hmc_pble_rsrc *pble_rsrc,
+					    struct i40iw_add_page_info *info)
+{
+	enum i40iw_status_code ret_code = 0;
+	struct sd_pd_idx *idx = &info->idx;
+	struct i40iw_chunk *chunk = info->chunk;
+	struct i40iw_hmc_info *hmc_info = info->hmc_info;
+	struct i40iw_hmc_sd_entry *sd_entry = info->sd_entry;
+	u32 offset = 0;
+
+	if (!sd_entry->valid) {
+		if (dev->is_pf) {
+			ret_code = i40iw_add_sd_table_entry(dev->hw, hmc_info,
+							    info->idx.sd_idx,
+							    I40IW_SD_TYPE_DIRECT,
+							    I40IW_HMC_DIRECT_BP_SIZE);
+			if (ret_code)
+				return ret_code;
+			chunk->type = I40IW_DMA_COHERENT;
+		}
+	}
+	offset = idx->rel_pd_idx << I40IW_HMC_PAGED_BP_SHIFT;
+	chunk->size = info->pages << I40IW_HMC_PAGED_BP_SHIFT;
+	chunk->vaddr = ((u8 *)sd_entry->u.bp.addr.va + offset);
+	chunk->fpm_addr = pble_rsrc->next_fpm_addr;
+	i40iw_debug(dev, I40IW_DEBUG_PBLE, "chunk_size[%d] = 0x%x vaddr=%p fpm_addr = %llx\n",
+		    chunk->size, chunk->size, chunk->vaddr, chunk->fpm_addr);
+	return 0;
+}
+
+/**
+ * i40iw_free_vmalloc_mem - free vmalloc during close
+ * @hw: hw struct
+ * @chunk: chunk information for vmalloc
+ */
+static void i40iw_free_vmalloc_mem(struct i40iw_hw *hw, struct i40iw_chunk *chunk)
+{
+	struct pci_dev *pcidev = (struct pci_dev *)hw->dev_context;
+	int i;
+
+	if (!chunk->pg_cnt)
+		goto done;
+	for (i = 0; i < chunk->pg_cnt; i++)
+		dma_unmap_page(&pcidev->dev, chunk->dmaaddrs[i], PAGE_SIZE, DMA_BIDIRECTIONAL);
+
+ done:
+	kfree(chunk->dmaaddrs);
+	chunk->dmaaddrs = NULL;
+	vfree(chunk->vaddr);
+	chunk->vaddr = NULL;
+	chunk->type = 0;
+}
+
+/**
+ * i40iw_get_vmalloc_mem - get 2M page for sd
+ * @hw: hardware address
+ * @chunk: chunk to adf
+ * @pg_cnt: #of 4 K pages
+ */
+static enum i40iw_status_code i40iw_get_vmalloc_mem(struct i40iw_hw *hw,
+						    struct i40iw_chunk *chunk,
+						    int pg_cnt)
+{
+	struct pci_dev *pcidev = (struct pci_dev *)hw->dev_context;
+	struct page *page;
+	u8 *addr;
+	u32 size;
+	int i;
+
+	chunk->dmaaddrs = kzalloc(pg_cnt << 3, GFP_KERNEL);
+	if (!chunk->dmaaddrs)
+		return I40IW_ERR_NO_MEMORY;
+	size = PAGE_SIZE * pg_cnt;
+	chunk->vaddr = vmalloc(size);
+	if (!chunk->vaddr) {
+		kfree(chunk->dmaaddrs);
+		chunk->dmaaddrs = NULL;
+		return I40IW_ERR_NO_MEMORY;
+	}
+	chunk->size = size;
+	addr = (u8 *)chunk->vaddr;
+	for (i = 0; i < pg_cnt; i++) {
+		page = vmalloc_to_page((void *)addr);
+		if (!page)
+			break;
+		chunk->dmaaddrs[i] = dma_map_page(&pcidev->dev, page, 0,
+						  PAGE_SIZE, DMA_BIDIRECTIONAL);
+		if (dma_mapping_error(&pcidev->dev, chunk->dmaaddrs[i]))
+			break;
+		addr += PAGE_SIZE;
+	}
+
+	chunk->pg_cnt = i;
+	chunk->type = I40IW_VMALLOC;
+	if (i == pg_cnt)
+		return 0;
+
+	i40iw_free_vmalloc_mem(hw, chunk);
+	return I40IW_ERR_NO_MEMORY;
+}
+
+/**
+ * fpm_to_idx - given fpm address, get pble index
+ * @pble_rsrc: pble resource management
+ * @addr: fpm address for index
+ */
+static inline u32 fpm_to_idx(struct i40iw_hmc_pble_rsrc *pble_rsrc, u64 addr)
+{
+	return (addr - (pble_rsrc->fpm_base_addr)) >> 3;
+}
+
+/**
+ * add_bp_pages - add backing pages for sd
+ * @dev: hardware control device structure
+ * @pble_rsrc: pble resource management
+ * @info: page info for sd
+ */
+static enum i40iw_status_code add_bp_pages(struct i40iw_sc_dev *dev,
+					   struct i40iw_hmc_pble_rsrc *pble_rsrc,
+					   struct i40iw_add_page_info *info)
+{
+	u8 *addr;
+	struct i40iw_dma_mem mem;
+	struct i40iw_hmc_pd_entry *pd_entry;
+	struct i40iw_hmc_sd_entry *sd_entry = info->sd_entry;
+	struct i40iw_hmc_info *hmc_info = info->hmc_info;
+	struct i40iw_chunk *chunk = info->chunk;
+	struct i40iw_manage_vf_pble_info vf_pble_info;
+	enum i40iw_status_code status = 0;
+	u32 rel_pd_idx = info->idx.rel_pd_idx;
+	u32 pd_idx = info->idx.pd_idx;
+	u32 i;
+
+	status = i40iw_get_vmalloc_mem(dev->hw, chunk, info->pages);
+	if (status)
+		return I40IW_ERR_NO_MEMORY;
+	status = i40iw_add_sd_table_entry(dev->hw, hmc_info,
+					  info->idx.sd_idx, I40IW_SD_TYPE_PAGED,
+					  I40IW_HMC_DIRECT_BP_SIZE);
+	if (status) {
+		i40iw_free_vmalloc_mem(dev->hw, chunk);
+		return status;
+	}
+	if (!dev->is_pf) {
+		status = i40iw_vchnl_vf_add_hmc_objs(dev, I40IW_HMC_IW_PBLE,
+						     fpm_to_idx(pble_rsrc,
+								pble_rsrc->next_fpm_addr),
+						     (info->pages << PBLE_512_SHIFT));
+		if (status) {
+			i40iw_pr_err("allocate PBLEs in the PF.  Error %i\n", status);
+			i40iw_free_vmalloc_mem(dev->hw, chunk);
+			return status;
+		}
+	}
+	addr = chunk->vaddr;
+	for (i = 0; i < info->pages; i++) {
+		mem.pa = chunk->dmaaddrs[i];
+		mem.size = PAGE_SIZE;
+		mem.va = (void *)(addr);
+		pd_entry = &sd_entry->u.pd_table.pd_entry[rel_pd_idx++];
+		if (!pd_entry->valid) {
+			status = i40iw_add_pd_table_entry(dev->hw, hmc_info, pd_idx++, &mem);
+			if (status)
+				goto error;
+			addr += PAGE_SIZE;
+		} else {
+			i40iw_pr_err("pd entry is valid expecting to be invalid\n");
+		}
+	}
+	if (!dev->is_pf) {
+		vf_pble_info.first_pd_index = info->idx.rel_pd_idx;
+		vf_pble_info.inv_pd_ent = false;
+		vf_pble_info.pd_entry_cnt = PBLE_PER_PAGE;
+		vf_pble_info.pd_pl_pba = sd_entry->u.pd_table.pd_page_addr.pa;
+		vf_pble_info.sd_index = info->idx.sd_idx;
+		status = i40iw_hw_manage_vf_pble_bp(dev->back_dev,
+						    &vf_pble_info, true);
+		if (status) {
+			i40iw_pr_err("CQP manage VF PBLE BP failed.  %i\n", status);
+			goto error;
+		}
+	}
+	chunk->fpm_addr = pble_rsrc->next_fpm_addr;
+	return 0;
+error:
+	i40iw_free_vmalloc_mem(dev->hw, chunk);
+	return status;
+}
+
+/**
+ * add_pble_pool - add a sd entry for pble resoure
+ * @dev: hardware control device structure
+ * @pble_rsrc: pble resource management
+ */
+static enum i40iw_status_code add_pble_pool(struct i40iw_sc_dev *dev,
+					    struct i40iw_hmc_pble_rsrc *pble_rsrc)
+{
+	struct i40iw_hmc_sd_entry *sd_entry;
+	struct i40iw_hmc_info *hmc_info;
+	struct i40iw_chunk *chunk;
+	struct i40iw_add_page_info info;
+	struct sd_pd_idx *idx = &info.idx;
+	enum i40iw_status_code ret_code = 0;
+	enum i40iw_sd_entry_type sd_entry_type;
+	u64 sd_reg_val = 0;
+	u32 pages;
+
+	if (pble_rsrc->unallocated_pble < PBLE_PER_PAGE)
+		return I40IW_ERR_NO_MEMORY;
+	if (pble_rsrc->next_fpm_addr & 0xfff) {
+		i40iw_pr_err("next fpm_addr %llx\n", pble_rsrc->next_fpm_addr);
+		return I40IW_ERR_INVALID_PAGE_DESC_INDEX;
+	}
+	chunk = kzalloc(sizeof(*chunk), GFP_KERNEL);
+	if (!chunk)
+		return I40IW_ERR_NO_MEMORY;
+	hmc_info = dev->hmc_info;
+	chunk->fpm_addr = pble_rsrc->next_fpm_addr;
+	get_sd_pd_idx(pble_rsrc, idx);
+	sd_entry = &hmc_info->sd_table.sd_entry[idx->sd_idx];
+	pages = (idx->rel_pd_idx) ? (I40IW_HMC_PD_CNT_IN_SD -
+			idx->rel_pd_idx) : I40IW_HMC_PD_CNT_IN_SD;
+	pages = min(pages, pble_rsrc->unallocated_pble >> PBLE_512_SHIFT);
+	if (!pages) {
+		ret_code = I40IW_ERR_NO_PBLCHUNKS_AVAILABLE;
+		goto error;
+	}
+	info.chunk = chunk;
+	info.hmc_info = hmc_info;
+	info.pages = pages;
+	info.sd_entry = sd_entry;
+	if (!sd_entry->valid) {
+		sd_entry_type = (!idx->rel_pd_idx &&
+				 (pages == I40IW_HMC_PD_CNT_IN_SD) &&
+				 dev->is_pf) ? I40IW_SD_TYPE_DIRECT : I40IW_SD_TYPE_PAGED;
+	} else {
+		sd_entry_type = sd_entry->entry_type;
+	}
+	i40iw_debug(dev, I40IW_DEBUG_PBLE,
+		    "pages = %d, unallocated_pble[%u] current_fpm_addr = %llx\n",
+		    pages, pble_rsrc->unallocated_pble, pble_rsrc->next_fpm_addr);
+	i40iw_debug(dev, I40IW_DEBUG_PBLE, "sd_entry_type = %d sd_entry valid = %d\n",
+		    sd_entry_type, sd_entry->valid);
+
+	if (sd_entry_type == I40IW_SD_TYPE_DIRECT)
+		ret_code = add_sd_direct(dev, pble_rsrc, &info);
+	if (ret_code)
+		sd_entry_type = I40IW_SD_TYPE_PAGED;
+	else
+		pble_rsrc->stats_direct_sds++;
+
+	if (sd_entry_type == I40IW_SD_TYPE_PAGED) {
+		ret_code = add_bp_pages(dev, pble_rsrc, &info);
+		if (ret_code)
+			goto error;
+		else
+			pble_rsrc->stats_paged_sds++;
+	}
+
+	if (gen_pool_add_virt(pble_rsrc->pinfo.pool, (unsigned long)chunk->vaddr,
+			      (phys_addr_t)chunk->fpm_addr, chunk->size, -1)) {
+		i40iw_pr_err("could not allocate memory by gen_pool_addr_virt()\n");
+		ret_code = I40IW_ERR_NO_MEMORY;
+		goto error;
+	}
+	pble_rsrc->next_fpm_addr += chunk->size;
+	i40iw_debug(dev, I40IW_DEBUG_PBLE, "next_fpm_addr = %llx chunk_size[%u] = 0x%x\n",
+		    pble_rsrc->next_fpm_addr, chunk->size, chunk->size);
+	pble_rsrc->unallocated_pble -= (chunk->size >> 3);
+	list_add(&chunk->list, &pble_rsrc->pinfo.clist);
+	sd_reg_val = (sd_entry_type == I40IW_SD_TYPE_PAGED) ?
+			sd_entry->u.pd_table.pd_page_addr.pa : sd_entry->u.bp.addr.pa;
+	if (sd_entry->valid)
+		return 0;
+	if (dev->is_pf)
+		ret_code = i40iw_hmc_sd_one(dev, hmc_info->hmc_fn_id,
+					    sd_reg_val, idx->sd_idx,
+					    sd_entry->entry_type, true);
+	if (ret_code) {
+		i40iw_pr_err("cqp cmd failed for sd (pbles)\n");
+		goto error;
+	}
+
+	sd_entry->valid = true;
+	return 0;
+ error:
+	kfree(chunk);
+	return ret_code;
+}
+
+/**
+ * free_lvl2 - fee level 2 pble
+ * @pble_rsrc: pble resource management
+ * @palloc: level 2 pble allocation
+ */
+static void free_lvl2(struct i40iw_hmc_pble_rsrc *pble_rsrc,
+		      struct i40iw_pble_alloc *palloc)
+{
+	u32 i;
+	struct gen_pool *pool;
+	struct i40iw_pble_level2 *lvl2 = &palloc->level2;
+	struct i40iw_pble_info *root = &lvl2->root;
+	struct i40iw_pble_info *leaf = lvl2->leaf;
+
+	pool = pble_rsrc->pinfo.pool;
+
+	for (i = 0; i < lvl2->leaf_cnt; i++, leaf++) {
+		if (leaf->addr)
+			gen_pool_free(pool, leaf->addr, (leaf->cnt << 3));
+		else
+			break;
+	}
+
+	if (root->addr)
+		gen_pool_free(pool, root->addr, (root->cnt << 3));
+
+	kfree(lvl2->leaf);
+	lvl2->leaf = NULL;
+}
+
+/**
+ * get_lvl2_pble - get level 2 pble resource
+ * @pble_rsrc: pble resource management
+ * @palloc: level 2 pble allocation
+ * @pool: pool pointer
+ */
+static enum i40iw_status_code get_lvl2_pble(struct i40iw_hmc_pble_rsrc *pble_rsrc,
+					    struct i40iw_pble_alloc *palloc,
+					    struct gen_pool *pool)
+{
+	u32 lf4k, lflast, total, i;
+	u32 pblcnt = PBLE_PER_PAGE;
+	u64 *addr;
+	struct i40iw_pble_level2 *lvl2 = &palloc->level2;
+	struct i40iw_pble_info *root = &lvl2->root;
+	struct i40iw_pble_info *leaf;
+
+	/* number of full 512 (4K) leafs) */
+	lf4k = palloc->total_cnt >> 9;
+	lflast = palloc->total_cnt % PBLE_PER_PAGE;
+	total = (lflast == 0) ? lf4k : lf4k + 1;
+	lvl2->leaf_cnt = total;
+
+	leaf = kzalloc((sizeof(*leaf) * total), GFP_ATOMIC);
+	if (!leaf)
+		return I40IW_ERR_NO_MEMORY;
+	lvl2->leaf = leaf;
+	/* allocate pbles for the root */
+	root->addr = gen_pool_alloc(pool, (total << 3));
+	if (!root->addr) {
+		kfree(lvl2->leaf);
+		lvl2->leaf = NULL;
+		return I40IW_ERR_NO_MEMORY;
+	}
+	root->idx = fpm_to_idx(pble_rsrc,
+			       (u64)gen_pool_virt_to_phys(pool, root->addr));
+	root->cnt = total;
+	addr = (u64 *)root->addr;
+	for (i = 0; i < total; i++, leaf++) {
+		pblcnt = (lflast && ((i + 1) == total)) ? lflast : PBLE_PER_PAGE;
+		leaf->addr = gen_pool_alloc(pool, (pblcnt << 3));
+		if (!leaf->addr)
+			goto error;
+		leaf->idx = fpm_to_idx(pble_rsrc, (u64)gen_pool_virt_to_phys(pool, leaf->addr));
+
+		leaf->cnt = pblcnt;
+		*addr = (u64)leaf->idx;
+		addr++;
+	}
+	palloc->level = I40IW_LEVEL_2;
+	pble_rsrc->stats_lvl2++;
+	return 0;
+ error:
+	free_lvl2(pble_rsrc, palloc);
+	return I40IW_ERR_NO_MEMORY;
+}
+
+/**
+ * get_lvl1_pble - get level 1 pble resource
+ * @dev: hardware control device structure
+ * @pble_rsrc: pble resource management
+ * @palloc: level 1 pble allocation
+ */
+static enum i40iw_status_code get_lvl1_pble(struct i40iw_sc_dev *dev,
+					    struct i40iw_hmc_pble_rsrc *pble_rsrc,
+					    struct i40iw_pble_alloc *palloc)
+{
+	u64 *addr;
+	struct gen_pool *pool;
+	struct i40iw_pble_info *lvl1 = &palloc->level1;
+
+	pool = pble_rsrc->pinfo.pool;
+	addr = (u64 *)gen_pool_alloc(pool, (palloc->total_cnt << 3));
+
+	if (!addr)
+		return I40IW_ERR_NO_MEMORY;
+
+	palloc->level = I40IW_LEVEL_1;
+	lvl1->addr = (unsigned long)addr;
+	lvl1->idx = fpm_to_idx(pble_rsrc, (u64)gen_pool_virt_to_phys(pool,
+			       (unsigned long)addr));
+	lvl1->cnt = palloc->total_cnt;
+	pble_rsrc->stats_lvl1++;
+	return 0;
+}
+
+/**
+ * get_lvl1_lvl2_pble - calls get_lvl1 and get_lvl2 pble routine
+ * @dev: i40iw_sc_dev struct
+ * @pble_rsrc:	pble resources
+ * @palloc: contains all inforamtion regarding pble (idx + pble addr)
+ * @pool: pointer to general purpose special memory pool descriptor
+ */
+static inline enum i40iw_status_code get_lvl1_lvl2_pble(struct i40iw_sc_dev *dev,
+							struct i40iw_hmc_pble_rsrc *pble_rsrc,
+							struct i40iw_pble_alloc *palloc,
+							struct gen_pool *pool)
+{
+	enum i40iw_status_code status = 0;
+
+	status = get_lvl1_pble(dev, pble_rsrc, palloc);
+	if (status && (palloc->total_cnt > PBLE_PER_PAGE))
+		status = get_lvl2_pble(pble_rsrc, palloc, pool);
+	return status;
+}
+
+/**
+ * i40iw_get_pble - allocate pbles from the pool
+ * @dev: i40iw_sc_dev struct
+ * @pble_rsrc:	pble resources
+ * @palloc: contains all inforamtion regarding pble (idx + pble addr)
+ * @pble_cnt: #of pbles requested
+ */
+enum i40iw_status_code i40iw_get_pble(struct i40iw_sc_dev *dev,
+				      struct i40iw_hmc_pble_rsrc *pble_rsrc,
+				      struct i40iw_pble_alloc *palloc,
+				      u32 pble_cnt)
+{
+	struct gen_pool *pool;
+	enum i40iw_status_code status = 0;
+	u32 max_sds = 0;
+	int i;
+
+	pool = pble_rsrc->pinfo.pool;
+	palloc->total_cnt = pble_cnt;
+	palloc->level = I40IW_LEVEL_0;
+	/*check first to see if we can get pble's without acquiring additional sd's */
+	status = get_lvl1_lvl2_pble(dev, pble_rsrc, palloc, pool);
+	if (!status)
+		goto exit;
+	max_sds = (palloc->total_cnt >> 18) + 1;
+	for (i = 0; i < max_sds; i++) {
+		status = add_pble_pool(dev, pble_rsrc);
+		if (status)
+			break;
+		status = get_lvl1_lvl2_pble(dev, pble_rsrc, palloc, pool);
+		if (!status)
+			break;
+	}
+exit:
+	if (!status)
+		pble_rsrc->stats_alloc_ok++;
+	else
+		pble_rsrc->stats_alloc_fail++;
+
+	return status;
+}
+
+/**
+ * i40iw_free_pble - put pbles back into pool
+ * @pble_rsrc:	pble resources
+ * @palloc: contains all inforamtion regarding pble resource being freed
+ */
+void i40iw_free_pble(struct i40iw_hmc_pble_rsrc *pble_rsrc,
+		     struct i40iw_pble_alloc *palloc)
+{
+	struct gen_pool *pool;
+
+	pool = pble_rsrc->pinfo.pool;
+	if (palloc->level == I40IW_LEVEL_2)
+		free_lvl2(pble_rsrc, palloc);
+	else
+		gen_pool_free(pool, palloc->level1.addr,
+			      (palloc->level1.cnt << 3));
+	pble_rsrc->stats_alloc_freed++;
+}

drivers/infiniband/hw/i40iw/i40iw_pble.h

+/*******************************************************************************
+*
+* Copyright (c) 2015-2016 Intel 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
+* OpenFabrics.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.
+*
+*******************************************************************************/
+
+#ifndef I40IW_PBLE_H
+#define I40IW_PBLE_H
+
+#define POOL_SHIFT      6
+#define PBLE_PER_PAGE   512
+#define I40IW_HMC_PAGED_BP_SHIFT 12
+#define PBLE_512_SHIFT  9
+
+enum i40iw_pble_level {
+	I40IW_LEVEL_0 = 0,
+	I40IW_LEVEL_1 = 1,
+	I40IW_LEVEL_2 = 2
+};
+
+enum i40iw_alloc_type {
+	I40IW_NO_ALLOC = 0,
+	I40IW_DMA_COHERENT = 1,
+	I40IW_VMALLOC = 2
+};
+
+struct i40iw_pble_info {
+	unsigned long addr;
+	u32 idx;
+	u32 cnt;
+};
+
+struct i40iw_pble_level2 {
+	struct i40iw_pble_info root;
+	struct i40iw_pble_info *leaf;
+	u32 leaf_cnt;
+};
+
+struct i40iw_pble_alloc {
+	u32 total_cnt;
+	enum i40iw_pble_level level;
+	union {
+		struct i40iw_pble_info level1;
+		struct i40iw_pble_level2 level2;
+	};
+};
+
+struct sd_pd_idx {
+	u32 sd_idx;
+	u32 pd_idx;
+	u32 rel_pd_idx;
+};
+
+struct i40iw_add_page_info {
+	struct i40iw_chunk *chunk;
+	struct i40iw_hmc_sd_entry *sd_entry;
+	struct i40iw_hmc_info *hmc_info;
+	struct sd_pd_idx idx;
+	u32 pages;
+};
+
+struct i40iw_chunk {
+	struct list_head list;
+	u32 size;
+	void *vaddr;
+	u64 fpm_addr;
+	u32 pg_cnt;
+	dma_addr_t *dmaaddrs;
+	enum i40iw_alloc_type type;
+};
+
+struct i40iw_pble_pool {
+	struct gen_pool *pool;
+	struct list_head clist;
+	u32 total_pble_alloc;
+	u32 free_pble_cnt;
+	u32 pool_shift;
+};
+
+struct i40iw_hmc_pble_rsrc {
+	u32 unallocated_pble;
+	u64 fpm_base_addr;
+	u64 next_fpm_addr;
+	struct i40iw_pble_pool pinfo;
+
+	u32 stats_direct_sds;
+	u32 stats_paged_sds;
+	u64 stats_alloc_ok;
+	u64 stats_alloc_fail;
+	u64 stats_alloc_freed;
+	u64 stats_lvl1;
+	u64 stats_lvl2;
+};
+
+void i40iw_destroy_pble_pool(struct i40iw_sc_dev *dev, struct i40iw_hmc_pble_rsrc *pble_rsrc);
+enum i40iw_status_code i40iw_hmc_init_pble(struct i40iw_sc_dev *dev,
+					   struct i40iw_hmc_pble_rsrc *pble_rsrc);
+void i40iw_free_pble(struct i40iw_hmc_pble_rsrc *pble_rsrc, struct i40iw_pble_alloc *palloc);
+enum i40iw_status_code i40iw_get_pble(struct i40iw_sc_dev *dev,
+				      struct i40iw_hmc_pble_rsrc *pble_rsrc,
+				      struct i40iw_pble_alloc *palloc,
+				      u32 pble_cnt);
+#endif