/*
 * Copyright (c) 2004 Topspin Communications.  All rights reserved.
 * Copyright (c) 2005, 2006, 2007, 2008 Mellanox Technologies. All rights reserved.
 * Copyright (c) 2006, 2007 Cisco Systems, 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 <linux/errno.h>
#include <linux/slab.h>

#include <linux/mlx4/cmd.h>

#include "mlx4.h"
#include "icm.h"

/*
 * Must be packed because mtt_seg is 64 bits but only aligned to 32 bits.
 */
struct mlx4_mpt_entry {
        __be32 flags;
        __be32 qpn;
        __be32 key;
        __be32 pd_flags;
        __be64 start;
        __be64 length;
        __be32 lkey;
        __be32 win_cnt;
        u8      reserved1[3];
        u8      mtt_rep;
        __be64 mtt_seg;
        __be32 mtt_sz;
        __be32 entity_size;
        __be32 first_byte_offset;
} __packed;

#define MLX4_MPT_FLAG_SW_OWNS       (0xfUL << 28)
#define MLX4_MPT_FLAG_FREE          (0x3UL << 28)
#define MLX4_MPT_FLAG_MIO           (1 << 17)
#define MLX4_MPT_FLAG_BIND_ENABLE   (1 << 15)
#define MLX4_MPT_FLAG_PHYSICAL      (1 <<  9)
#define MLX4_MPT_FLAG_REGION        (1 <<  8)

#define MLX4_MPT_PD_FLAG_FAST_REG   (1 << 27)
#define MLX4_MPT_PD_FLAG_RAE        (1 << 28)
#define MLX4_MPT_PD_FLAG_EN_INV     (3 << 24)

#define MLX4_MPT_STATUS_SW              0xF0
#define MLX4_MPT_STATUS_HW              0x00

static u32 mlx4_buddy_alloc(struct mlx4_buddy *buddy, int order)
{
        int o;
        int m;
        u32 seg;

        spin_lock(&buddy->lock);

        for (o = order; o <= buddy->max_order; ++o)
                if (buddy->num_free[o]) {
                        m = 1 << (buddy->max_order - o);
                        seg = find_first_bit(buddy->bits[o], m);
                        if (seg < m)
                                goto found;
                }

        spin_unlock(&buddy->lock);
        return -1;

 found:
        clear_bit(seg, buddy->bits[o]);
        --buddy->num_free[o];

        while (o > order) {
                --o;
                seg <<= 1;
                set_bit(seg ^ 1, buddy->bits[o]);
                ++buddy->num_free[o];
        }

        spin_unlock(&buddy->lock);

        seg <<= order;

        return seg;
}

static void mlx4_buddy_free(struct mlx4_buddy *buddy, u32 seg, int order)
{
        seg >>= order;

        spin_lock(&buddy->lock);

        while (test_bit(seg ^ 1, buddy->bits[order])) {
                clear_bit(seg ^ 1, buddy->bits[order]);
                --buddy->num_free[order];
                seg >>= 1;
                ++order;
        }

        set_bit(seg, buddy->bits[order]);
        ++buddy->num_free[order];

        spin_unlock(&buddy->lock);
}

static int mlx4_buddy_init(struct mlx4_buddy *buddy, int max_order)
{
        int i, s;

        buddy->max_order = max_order;
        spin_lock_init(&buddy->lock);

        buddy->bits = kzalloc((buddy->max_order + 1) * sizeof (long *),
                              GFP_KERNEL);
        buddy->num_free = kzalloc((buddy->max_order + 1) * sizeof (int *),
                                  GFP_KERNEL);
        if (!buddy->bits || !buddy->num_free)
                goto err_out;

        for (i = 0; i <= buddy->max_order; ++i) {
                s = BITS_TO_LONGS(1 << (buddy->max_order - i));
                buddy->bits[i] = kmalloc(s * sizeof (long), GFP_KERNEL);
                if (!buddy->bits[i])
                        goto err_out_free;
                bitmap_zero(buddy->bits[i], 1 << (buddy->max_order - i));
        }

        set_bit(0, buddy->bits[buddy->max_order]);
        buddy->num_free[buddy->max_order] = 1;

        return 0;

err_out_free:
        for (i = 0; i <= buddy->max_order; ++i)
                kfree(buddy->bits[i]);

err_out:
        kfree(buddy->bits);
        kfree(buddy->num_free);

        return -ENOMEM;
}

static void mlx4_buddy_cleanup(struct mlx4_buddy *buddy)
{
        int i;

        for (i = 0; i <= buddy->max_order; ++i)
                kfree(buddy->bits[i]);

        kfree(buddy->bits);
        kfree(buddy->num_free);
}

static u32 mlx4_alloc_mtt_range(struct mlx4_dev *dev, int order)
{
        struct mlx4_mr_table *mr_table = &mlx4_priv(dev)->mr_table;
        u32 seg;

        seg = mlx4_buddy_alloc(&mr_table->mtt_buddy, order);
        if (seg == -1)
                return -1;

        if (mlx4_table_get_range(dev, &mr_table->mtt_table, seg,
                                 seg + (1 << order) - 1)) {
                mlx4_buddy_free(&mr_table->mtt_buddy, seg, order);
                return -1;
        }

        return seg;
}

int mlx4_mtt_init(struct mlx4_dev *dev, int npages, int page_shift,
                  struct mlx4_mtt *mtt)
{
        int i;

        if (!npages) {
                mtt->order      = -1;
                mtt->page_shift = MLX4_ICM_PAGE_SHIFT;
                return 0;
        } else
                mtt->page_shift = page_shift;

        for (mtt->order = 0, i = dev->caps.mtts_per_seg; i < npages; i <<= 1)
                ++mtt->order;

        mtt->first_seg = mlx4_alloc_mtt_range(dev, mtt->order);
        if (mtt->first_seg == -1)
                return -ENOMEM;

        return 0;
}
EXPORT_SYMBOL_GPL(mlx4_mtt_init);

void mlx4_mtt_cleanup(struct mlx4_dev *dev, struct mlx4_mtt *mtt)
{
        struct mlx4_mr_table *mr_table = &mlx4_priv(dev)->mr_table;

        if (mtt->order < 0)
                return;

        mlx4_buddy_free(&mr_table->mtt_buddy, mtt->first_seg, mtt->order);
        mlx4_table_put_range(dev, &mr_table->mtt_table, mtt->first_seg,
                             mtt->first_seg + (1 << mtt->order) - 1);
}
EXPORT_SYMBOL_GPL(mlx4_mtt_cleanup);

u64 mlx4_mtt_addr(struct mlx4_dev *dev, struct mlx4_mtt *mtt)
{
        return (u64) mtt->first_seg * dev->caps.mtt_entry_sz;
}
EXPORT_SYMBOL_GPL(mlx4_mtt_addr);

static u32 hw_index_to_key(u32 ind)
{
        return (ind >> 24) | (ind << 8);
}

static u32 key_to_hw_index(u32 key)
{
        return (key << 24) | (key >> 8);
}

static int mlx4_SW2HW_MPT(struct mlx4_dev *dev, struct mlx4_cmd_mailbox *mailbox,
                          int mpt_index)
{
        return mlx4_cmd(dev, mailbox->dma, mpt_index, 0, MLX4_CMD_SW2HW_MPT,
                        MLX4_CMD_TIME_CLASS_B);
}

static int mlx4_HW2SW_MPT(struct mlx4_dev *dev, struct mlx4_cmd_mailbox *mailbox,
                          int mpt_index)
{
        return mlx4_cmd_box(dev, 0, mailbox ? mailbox->dma : 0, mpt_index,
                            !mailbox, MLX4_CMD_HW2SW_MPT, MLX4_CMD_TIME_CLASS_B);
}

int mlx4_mr_alloc(struct mlx4_dev *dev, u32 pd, u64 iova, u64 size, u32 access,
                  int npages, int page_shift, struct mlx4_mr *mr)
{
        struct mlx4_priv *priv = mlx4_priv(dev);
        u32 index;
        int err;

        index = mlx4_bitmap_alloc(&priv->mr_table.mpt_bitmap);
        if (index == -1)
                return -ENOMEM;

        mr->iova       = iova;
        mr->size       = size;
        mr->pd         = pd;
        mr->access     = access;
        mr->enabled    = 0;
        mr->key        = hw_index_to_key(index);

        err = mlx4_mtt_init(dev, npages, page_shift, &mr->mtt);
        if (err)
                mlx4_bitmap_free(&priv->mr_table.mpt_bitmap, index);

        return err;
}
EXPORT_SYMBOL_GPL(mlx4_mr_alloc);

void mlx4_mr_free(struct mlx4_dev *dev, struct mlx4_mr *mr)
{
        struct mlx4_priv *priv = mlx4_priv(dev);
        int err;

        if (mr->enabled) {
                err = mlx4_HW2SW_MPT(dev, NULL,
                                     key_to_hw_index(mr->key) &
                                     (dev->caps.num_mpts - 1));
                if (err)
                        mlx4_warn(dev, "HW2SW_MPT failed (%d)\n", err);
        }

        mlx4_mtt_cleanup(dev, &mr->mtt);
        mlx4_bitmap_free(&priv->mr_table.mpt_bitmap, key_to_hw_index(mr->key));
}
EXPORT_SYMBOL_GPL(mlx4_mr_free);

int mlx4_mr_enable(struct mlx4_dev *dev, struct mlx4_mr *mr)
{
        struct mlx4_mr_table *mr_table = &mlx4_priv(dev)->mr_table;
        struct mlx4_cmd_mailbox *mailbox;
        struct mlx4_mpt_entry *mpt_entry;
        int err;

        err = mlx4_table_get(dev, &mr_table->dmpt_table, key_to_hw_index(mr->key));
        if (err)
                return err;

        mailbox = mlx4_alloc_cmd_mailbox(dev);
        if (IS_ERR(mailbox)) {
                err = PTR_ERR(mailbox);
                goto err_table;
        }
        mpt_entry = mailbox->buf;

        memset(mpt_entry, 0, sizeof *mpt_entry);

        mpt_entry->flags = cpu_to_be32(MLX4_MPT_FLAG_MIO         |
                                       MLX4_MPT_FLAG_REGION      |
                                       mr->access);

        mpt_entry->key         = cpu_to_be32(key_to_hw_index(mr->key));
        mpt_entry->pd_flags    = cpu_to_be32(mr->pd | MLX4_MPT_PD_FLAG_EN_INV);
        mpt_entry->start       = cpu_to_be64(mr->iova);
        mpt_entry->length      = cpu_to_be64(mr->size);
        mpt_entry->entity_size = cpu_to_be32(mr->mtt.page_shift);

        if (mr->mtt.order < 0) {
                mpt_entry->flags |= cpu_to_be32(MLX4_MPT_FLAG_PHYSICAL);
                mpt_entry->mtt_seg = 0;
        } else {
                mpt_entry->mtt_seg = cpu_to_be64(mlx4_mtt_addr(dev, &mr->mtt));
        }

        if (mr->mtt.order >= 0 && mr->mtt.page_shift == 0) {
                /* fast register MR in free state */
                mpt_entry->flags    |= cpu_to_be32(MLX4_MPT_FLAG_FREE);
                mpt_entry->pd_flags |= cpu_to_be32(MLX4_MPT_PD_FLAG_FAST_REG |
                                                   MLX4_MPT_PD_FLAG_RAE);
                mpt_entry->mtt_sz    = cpu_to_be32((1 << mr->mtt.order) *
                                                   dev->caps.mtts_per_seg);
        } else {
                mpt_entry->flags    |= cpu_to_be32(MLX4_MPT_FLAG_SW_OWNS);
        }

        err = mlx4_SW2HW_MPT(dev, mailbox,
                             key_to_hw_index(mr->key) & (dev->caps.num_mpts - 1));
        if (err) {
                mlx4_warn(dev, "SW2HW_MPT failed (%d)\n", err);
                goto err_cmd;
        }

        mr->enabled = 1;

        mlx4_free_cmd_mailbox(dev, mailbox);

        return 0;

err_cmd:
        mlx4_free_cmd_mailbox(dev, mailbox);

err_table:
        mlx4_table_put(dev, &mr_table->dmpt_table, key_to_hw_index(mr->key));
        return err;
}
EXPORT_SYMBOL_GPL(mlx4_mr_enable);

static int mlx4_write_mtt_chunk(struct mlx4_dev *dev, struct mlx4_mtt *mtt,
                                int start_index, int npages, u64 *page_list)
{
        struct mlx4_priv *priv = mlx4_priv(dev);
        __be64 *mtts;
        dma_addr_t dma_handle;
        int i;
        int s = start_index * sizeof (u64);

        /* All MTTs must fit in the same page */
        if (start_index / (PAGE_SIZE / sizeof (u64)) !=
            (start_index + npages - 1) / (PAGE_SIZE / sizeof (u64)))
                return -EINVAL;

        if (start_index & (dev->caps.mtts_per_seg - 1))
                return -EINVAL;

        mtts = mlx4_table_find(&priv->mr_table.mtt_table, mtt->first_seg +
                                s / dev->caps.mtt_entry_sz, &dma_handle);
        if (!mtts)
                return -ENOMEM;

        dma_sync_single_for_cpu(&dev->pdev->dev, dma_handle,
                                npages * sizeof (u64), DMA_TO_DEVICE);

        for (i = 0; i < npages; ++i)
                mtts[i] = cpu_to_be64(page_list[i] | MLX4_MTT_FLAG_PRESENT);

        dma_sync_single_for_device(&dev->pdev->dev, dma_handle,
                                   npages * sizeof (u64), DMA_TO_DEVICE);

        return 0;
}

int mlx4_write_mtt(struct mlx4_dev *dev, struct mlx4_mtt *mtt,
                   int start_index, int npages, u64 *page_list)
{
        int chunk;
        int err;

        if (mtt->order < 0)
                return -EINVAL;

        while (npages > 0) {
                chunk = min_t(int, PAGE_SIZE / sizeof(u64), npages);
                err = mlx4_write_mtt_chunk(dev, mtt, start_index, chunk, page_list);
                if (err)
                        return err;

                npages      -= chunk;
                start_index += chunk;
                page_list   += chunk;
        }

        return 0;
}
EXPORT_SYMBOL_GPL(mlx4_write_mtt);

int mlx4_buf_write_mtt(struct mlx4_dev *dev, struct mlx4_mtt *mtt,
                       struct mlx4_buf *buf)
{
        u64 *page_list;
        int err;
        int i;

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

        for (i = 0; i < buf->npages; ++i)
                if (buf->nbufs == 1)
                        page_list[i] = buf->direct.map + (i << buf->page_shift);
                else
                        page_list[i] = buf->page_list[i].map;

        err = mlx4_write_mtt(dev, mtt, 0, buf->npages, page_list);

        kfree(page_list);
        return err;
}
EXPORT_SYMBOL_GPL(mlx4_buf_write_mtt);

int mlx4_init_mr_table(struct mlx4_dev *dev)
{
        struct mlx4_mr_table *mr_table = &mlx4_priv(dev)->mr_table;
        int err;

        err = mlx4_bitmap_init(&mr_table->mpt_bitmap, dev->caps.num_mpts,
                               ~0, dev->caps.reserved_mrws, 0);
        if (err)
                return err;

        err = mlx4_buddy_init(&mr_table->mtt_buddy,
                              ilog2(dev->caps.num_mtt_segs));
        if (err)
                goto err_buddy;

        if (dev->caps.reserved_mtts) {
                if (mlx4_alloc_mtt_range(dev, fls(dev->caps.reserved_mtts - 1)) == -1) {
                        mlx4_warn(dev, "MTT table of order %d is too small.\n",
                                  mr_table->mtt_buddy.max_order);
                        err = -ENOMEM;
                        goto err_reserve_mtts;
                }
        }

        return 0;

err_reserve_mtts:
        mlx4_buddy_cleanup(&mr_table->mtt_buddy);

err_buddy:
        mlx4_bitmap_cleanup(&mr_table->mpt_bitmap);

        return err;
}

void mlx4_cleanup_mr_table(struct mlx4_dev *dev)
{
        struct mlx4_mr_table *mr_table = &mlx4_priv(dev)->mr_table;

        mlx4_buddy_cleanup(&mr_table->mtt_buddy);
        mlx4_bitmap_cleanup(&mr_table->mpt_bitmap);
}

static inline int mlx4_check_fmr(struct mlx4_fmr *fmr, u64 *page_list,
                                  int npages, u64 iova)
{
        int i, page_mask;

        if (npages > fmr->max_pages)
                return -EINVAL;

        page_mask = (1 << fmr->page_shift) - 1;

        /* We are getting page lists, so va must be page aligned. */
        if (iova & page_mask)
                return -EINVAL;

        /* Trust the user not to pass misaligned data in page_list */
        if (0)
                for (i = 0; i < npages; ++i) {
                        if (page_list[i] & ~page_mask)
                                return -EINVAL;
                }

        if (fmr->maps >= fmr->max_maps)
                return -EINVAL;

        return 0;
}

int mlx4_map_phys_fmr(struct mlx4_dev *dev, struct mlx4_fmr *fmr, u64 *page_list,
                      int npages, u64 iova, u32 *lkey, u32 *rkey)
{
        u32 key;
        int i, err;

        err = mlx4_check_fmr(fmr, page_list, npages, iova);
        if (err)
                return err;

        ++fmr->maps;

        key = key_to_hw_index(fmr->mr.key);
        key += dev->caps.num_mpts;
        *lkey = *rkey = fmr->mr.key = hw_index_to_key(key);

        *(u8 *) fmr->mpt = MLX4_MPT_STATUS_SW;

        /* Make sure MPT status is visible before writing MTT entries */
        wmb();

        dma_sync_single_for_cpu(&dev->pdev->dev, fmr->dma_handle,
                                npages * sizeof(u64), DMA_TO_DEVICE);

        for (i = 0; i < npages; ++i)
                fmr->mtts[i] = cpu_to_be64(page_list[i] | MLX4_MTT_FLAG_PRESENT);

        dma_sync_single_for_device(&dev->pdev->dev, fmr->dma_handle,
                                   npages * sizeof(u64), DMA_TO_DEVICE);

        fmr->mpt->key    = cpu_to_be32(key);
        fmr->mpt->lkey   = cpu_to_be32(key);
        fmr->mpt->length = cpu_to_be64(npages * (1ull << fmr->page_shift));
        fmr->mpt->start  = cpu_to_be64(iova);

        /* Make MTT entries are visible before setting MPT status */
        wmb();

        *(u8 *) fmr->mpt = MLX4_MPT_STATUS_HW;

        /* Make sure MPT status is visible before consumer can use FMR */
        wmb();

        return 0;
}
EXPORT_SYMBOL_GPL(mlx4_map_phys_fmr);

int mlx4_fmr_alloc(struct mlx4_dev *dev, u32 pd, u32 access, int max_pages,
                   int max_maps, u8 page_shift, struct mlx4_fmr *fmr)
{
        struct mlx4_priv *priv = mlx4_priv(dev);
        u64 mtt_seg;
        int err = -ENOMEM;

        if (page_shift < (ffs(dev->caps.page_size_cap) - 1) || page_shift >= 32)
                return -EINVAL;

        /* All MTTs must fit in the same page */
        if (max_pages * sizeof *fmr->mtts > PAGE_SIZE)
                return -EINVAL;

        fmr->page_shift = page_shift;
        fmr->max_pages  = max_pages;
        fmr->max_maps   = max_maps;
        fmr->maps = 0;

        err = mlx4_mr_alloc(dev, pd, 0, 0, access, max_pages,
                            page_shift, &fmr->mr);
        if (err)
                return err;

        mtt_seg = fmr->mr.mtt.first_seg * dev->caps.mtt_entry_sz;

        fmr->mtts = mlx4_table_find(&priv->mr_table.mtt_table,
                                    fmr->mr.mtt.first_seg,
                                    &fmr->dma_handle);
        if (!fmr->mtts) {
                err = -ENOMEM;
                goto err_free;
        }

        return 0;

err_free:
        mlx4_mr_free(dev, &fmr->mr);
        return err;
}
EXPORT_SYMBOL_GPL(mlx4_fmr_alloc);

int mlx4_fmr_enable(struct mlx4_dev *dev, struct mlx4_fmr *fmr)
{
        struct mlx4_priv *priv = mlx4_priv(dev);
        int err;

        err = mlx4_mr_enable(dev, &fmr->mr);
        if (err)
                return err;

        fmr->mpt = mlx4_table_find(&priv->mr_table.dmpt_table,
                                    key_to_hw_index(fmr->mr.key), NULL);
        if (!fmr->mpt)
                return -ENOMEM;

        return 0;
}
EXPORT_SYMBOL_GPL(mlx4_fmr_enable);

void mlx4_fmr_unmap(struct mlx4_dev *dev, struct mlx4_fmr *fmr,
                    u32 *lkey, u32 *rkey)
{
        if (!fmr->maps)
                return;

        fmr->maps = 0;

        *(u8 *) fmr->mpt = MLX4_MPT_STATUS_SW;
}
EXPORT_SYMBOL_GPL(mlx4_fmr_unmap);

int mlx4_fmr_free(struct mlx4_dev *dev, struct mlx4_fmr *fmr)
{
        if (fmr->maps)
                return -EBUSY;

        fmr->mr.enabled = 0;
        mlx4_mr_free(dev, &fmr->mr);

        return 0;
}
EXPORT_SYMBOL_GPL(mlx4_fmr_free);

int mlx4_SYNC_TPT(struct mlx4_dev *dev)
{
        return mlx4_cmd(dev, 0, 0, 0, MLX4_CMD_SYNC_TPT, 1000);
}
EXPORT_SYMBOL_GPL(mlx4_SYNC_TPT);