/*
 * Copyright (c) 2013, 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
 * 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/pci.h>

#include "usnic_ib.h"
#include "vnic_resource.h"
#include "usnic_log.h"
#include "usnic_vnic.h"

struct usnic_vnic {
        struct vnic_dev                 *vdev;
        struct vnic_dev_bar             bar[PCI_NUM_RESOURCES];
        struct usnic_vnic_res_chunk     chunks[USNIC_VNIC_RES_TYPE_MAX];
        spinlock_t                      res_lock;
};

static enum vnic_res_type _to_vnic_res_type(enum usnic_vnic_res_type res_type)
{
#define DEFINE_USNIC_VNIC_RES_AT(usnic_vnic_res_t, vnic_res_type, desc, val) \
                vnic_res_type,
#define DEFINE_USNIC_VNIC_RES(usnic_vnic_res_t, vnic_res_type, desc) \
                vnic_res_type,
        static enum vnic_res_type usnic_vnic_type_2_vnic_type[] = {
                                                USNIC_VNIC_RES_TYPES};
#undef DEFINE_USNIC_VNIC_RES
#undef DEFINE_USNIC_VNIC_RES_AT

        if (res_type >= USNIC_VNIC_RES_TYPE_MAX)
                return RES_TYPE_MAX;

        return usnic_vnic_type_2_vnic_type[res_type];
}

const char *usnic_vnic_res_type_to_str(enum usnic_vnic_res_type res_type)
{
#define DEFINE_USNIC_VNIC_RES_AT(usnic_vnic_res_t, vnic_res_type, desc, val) \
                desc,
#define DEFINE_USNIC_VNIC_RES(usnic_vnic_res_t, vnic_res_type, desc) \
                desc,
        static const char * const usnic_vnic_res_type_desc[] = {
                                                USNIC_VNIC_RES_TYPES};
#undef DEFINE_USNIC_VNIC_RES
#undef DEFINE_USNIC_VNIC_RES_AT

        if (res_type >= USNIC_VNIC_RES_TYPE_MAX)
                return "unknown";

        return usnic_vnic_res_type_desc[res_type];

}

const char *usnic_vnic_pci_name(struct usnic_vnic *vnic)
{
        return pci_name(usnic_vnic_get_pdev(vnic));
}

int usnic_vnic_dump(struct usnic_vnic *vnic, char *buf,
                        int buf_sz,
                        void *hdr_obj,
                        int (*printtitle)(void *, char*, int),
                        int (*printcols)(char *, int),
                        int (*printrow)(void *, char *, int))
{
        struct usnic_vnic_res_chunk *chunk;
        struct usnic_vnic_res *res;
        struct vnic_dev_bar *bar0;
        int i, j, offset;

        offset = 0;
        bar0 = usnic_vnic_get_bar(vnic, 0);
        offset += scnprintf(buf + offset, buf_sz - offset,
                        "VF:%hu BAR0 bus_addr=%pa vaddr=0x%p size=%ld ",
                        usnic_vnic_get_index(vnic),
                        &bar0->bus_addr,
                        bar0->vaddr, bar0->len);
        if (printtitle)
                offset += printtitle(hdr_obj, buf + offset, buf_sz - offset);
        offset += scnprintf(buf + offset, buf_sz - offset, "\n");
        offset += scnprintf(buf + offset, buf_sz - offset,
                        "|RES\t|CTRL_PIN\t\t|IN_USE\t");
        if (printcols)
                offset += printcols(buf + offset, buf_sz - offset);
        offset += scnprintf(buf + offset, buf_sz - offset, "\n");

        spin_lock(&vnic->res_lock);
        for (i = 0; i < ARRAY_SIZE(vnic->chunks); i++) {
                chunk = &vnic->chunks[i];
                for (j = 0; j < chunk->cnt; j++) {
                        res = chunk->res[j];
                        offset += scnprintf(buf + offset, buf_sz - offset,
                                        "|%s[%u]\t|0x%p\t|%u\t",
                                        usnic_vnic_res_type_to_str(res->type),
                                        res->vnic_idx, res->ctrl, !!res->owner);
                        if (printrow) {
                                offset += printrow(res->owner, buf + offset,
                                                        buf_sz - offset);
                        }
                        offset += scnprintf(buf + offset, buf_sz - offset,
                                                "\n");
                }
        }
        spin_unlock(&vnic->res_lock);
        return offset;
}

void usnic_vnic_res_spec_update(struct usnic_vnic_res_spec *spec,
                                enum usnic_vnic_res_type trgt_type,
                                u16 cnt)
{
        int i;

        for (i = 0; i < USNIC_VNIC_RES_TYPE_MAX; i++) {
                if (spec->resources[i].type == trgt_type) {
                        spec->resources[i].cnt = cnt;
                        return;
                }
        }

        WARN_ON(1);
}

int usnic_vnic_res_spec_satisfied(const struct usnic_vnic_res_spec *min_spec,
                                        struct usnic_vnic_res_spec *res_spec)
{
        int found, i, j;

        for (i = 0; i < USNIC_VNIC_RES_TYPE_MAX; i++) {
                found = 0;

                for (j = 0; j < USNIC_VNIC_RES_TYPE_MAX; j++) {
                        if (res_spec->resources[i].type !=
                                min_spec->resources[i].type)
                                continue;
                        found = 1;
                        if (min_spec->resources[i].cnt >
                                        res_spec->resources[i].cnt)
                                return -EINVAL;
                        break;
                }

                if (!found)
                        return -EINVAL;
        }
        return 0;
}

int usnic_vnic_spec_dump(char *buf, int buf_sz,
                                struct usnic_vnic_res_spec *res_spec)
{
        enum usnic_vnic_res_type res_type;
        int res_cnt;
        int i;
        int offset = 0;

        for (i = 0; i < USNIC_VNIC_RES_TYPE_MAX; i++) {
                res_type = res_spec->resources[i].type;
                res_cnt = res_spec->resources[i].cnt;
                offset += scnprintf(buf + offset, buf_sz - offset,
                                "Res: %s Cnt: %d ",
                                usnic_vnic_res_type_to_str(res_type),
                                res_cnt);
        }

        return offset;
}

int usnic_vnic_check_room(struct usnic_vnic *vnic,
                                struct usnic_vnic_res_spec *res_spec)
{
        int i;
        enum usnic_vnic_res_type res_type;
        int res_cnt;

        for (i = 0; i < USNIC_VNIC_RES_TYPE_MAX; i++) {
                res_type = res_spec->resources[i].type;
                res_cnt = res_spec->resources[i].cnt;

                if (res_type == USNIC_VNIC_RES_TYPE_EOL)
                        break;

                if (res_cnt > usnic_vnic_res_free_cnt(vnic, res_type))
                        return -EBUSY;
        }

        return 0;
}

int usnic_vnic_res_cnt(struct usnic_vnic *vnic,
                                enum usnic_vnic_res_type type)
{
        return vnic->chunks[type].cnt;
}

int usnic_vnic_res_free_cnt(struct usnic_vnic *vnic,
                                enum usnic_vnic_res_type type)
{
        return vnic->chunks[type].free_cnt;
}

struct usnic_vnic_res_chunk *
usnic_vnic_get_resources(struct usnic_vnic *vnic, enum usnic_vnic_res_type type,
                                int cnt, void *owner)
{
        struct usnic_vnic_res_chunk *src, *ret;
        struct usnic_vnic_res *res;
        int i;

        if (usnic_vnic_res_free_cnt(vnic, type) < cnt || cnt < 0 || !owner)
                return ERR_PTR(-EINVAL);

        ret = kzalloc_obj(*ret, GFP_ATOMIC);
        if (!ret)
                return ERR_PTR(-ENOMEM);

        if (cnt > 0) {
                ret->res = kzalloc_objs(*(ret->res), cnt, GFP_ATOMIC);
                if (!ret->res) {
                        kfree(ret);
                        return ERR_PTR(-ENOMEM);
                }

                spin_lock(&vnic->res_lock);
                src = &vnic->chunks[type];
                for (i = 0; i < src->cnt && ret->cnt < cnt; i++) {
                        res = src->res[i];
                        if (!res->owner) {
                                src->free_cnt--;
                                res->owner = owner;
                                ret->res[ret->cnt++] = res;
                        }
                }

                spin_unlock(&vnic->res_lock);
        }
        ret->type = type;
        ret->vnic = vnic;
        WARN_ON(ret->cnt != cnt);

        return ret;
}

void usnic_vnic_put_resources(struct usnic_vnic_res_chunk *chunk)
{

        struct usnic_vnic_res *res;
        int i;
        struct usnic_vnic *vnic = chunk->vnic;

        if (chunk->cnt > 0) {
                spin_lock(&vnic->res_lock);
                while ((i = --chunk->cnt) >= 0) {
                        res = chunk->res[i];
                        chunk->res[i] = NULL;
                        res->owner = NULL;
                        vnic->chunks[res->type].free_cnt++;
                }
                spin_unlock(&vnic->res_lock);
        }

        kfree(chunk->res);
        kfree(chunk);
}

u16 usnic_vnic_get_index(struct usnic_vnic *vnic)
{
        return usnic_vnic_get_pdev(vnic)->devfn - 1;
}

static int usnic_vnic_alloc_res_chunk(struct usnic_vnic *vnic,
                                        enum usnic_vnic_res_type type,
                                        struct usnic_vnic_res_chunk *chunk)
{
        int cnt, err, i;
        struct usnic_vnic_res *res;

        cnt = vnic_dev_get_res_count(vnic->vdev, _to_vnic_res_type(type));
        if (cnt < 1) {
                usnic_err("Wrong res count with cnt %d\n", cnt);
                return -EINVAL;
        }

        chunk->cnt = chunk->free_cnt = cnt;
        chunk->res = kzalloc_objs(*(chunk->res), cnt);
        if (!chunk->res)
                return -ENOMEM;

        for (i = 0; i < cnt; i++) {
                res = kzalloc_obj(*res);
                if (!res) {
                        err = -ENOMEM;
                        goto fail;
                }
                res->type = type;
                res->vnic_idx = i;
                res->vnic = vnic;
                res->ctrl = vnic_dev_get_res(vnic->vdev,
                                                _to_vnic_res_type(type), i);
                chunk->res[i] = res;
        }

        chunk->vnic = vnic;
        return 0;
fail:
        for (i--; i >= 0; i--)
                kfree(chunk->res[i]);
        kfree(chunk->res);
        return err;
}

static void usnic_vnic_free_res_chunk(struct usnic_vnic_res_chunk *chunk)
{
        int i;
        for (i = 0; i < chunk->cnt; i++)
                kfree(chunk->res[i]);
        kfree(chunk->res);
}

static int usnic_vnic_discover_resources(struct pci_dev *pdev,
                                                struct usnic_vnic *vnic)
{
        enum usnic_vnic_res_type res_type;
        int i;
        int err = 0;

        for (i = 0; i < ARRAY_SIZE(vnic->bar); i++) {
                if (!(pci_resource_flags(pdev, i) & IORESOURCE_MEM))
                        continue;
                vnic->bar[i].len = pci_resource_len(pdev, i);
                vnic->bar[i].vaddr = pci_iomap(pdev, i, vnic->bar[i].len);
                if (!vnic->bar[i].vaddr) {
                        usnic_err("Cannot memory-map BAR %d, aborting\n",
                                        i);
                        err = -ENODEV;
                        goto out_clean_bar;
                }
                vnic->bar[i].bus_addr = pci_resource_start(pdev, i);
        }

        vnic->vdev = vnic_dev_register(NULL, pdev, pdev, vnic->bar,
                        ARRAY_SIZE(vnic->bar));
        if (!vnic->vdev) {
                usnic_err("Failed to register device %s\n",
                                pci_name(pdev));
                err = -EINVAL;
                goto out_clean_bar;
        }

        for (res_type = USNIC_VNIC_RES_TYPE_EOL + 1;
                        res_type < USNIC_VNIC_RES_TYPE_MAX; res_type++) {
                err = usnic_vnic_alloc_res_chunk(vnic, res_type,
                                                &vnic->chunks[res_type]);
                if (err)
                        goto out_clean_chunks;
        }

        return 0;

out_clean_chunks:
        for (res_type--; res_type > USNIC_VNIC_RES_TYPE_EOL; res_type--)
                usnic_vnic_free_res_chunk(&vnic->chunks[res_type]);
        vnic_dev_unregister(vnic->vdev);
out_clean_bar:
        for (i = 0; i < ARRAY_SIZE(vnic->bar); i++) {
                if (!(pci_resource_flags(pdev, i) & IORESOURCE_MEM))
                        continue;
                if (!vnic->bar[i].vaddr)
                        break;

                iounmap(vnic->bar[i].vaddr);
        }

        return err;
}

struct pci_dev *usnic_vnic_get_pdev(struct usnic_vnic *vnic)
{
        return vnic_dev_get_pdev(vnic->vdev);
}

struct vnic_dev_bar *usnic_vnic_get_bar(struct usnic_vnic *vnic,
                                int bar_num)
{
        return (bar_num < ARRAY_SIZE(vnic->bar)) ? &vnic->bar[bar_num] : NULL;
}

static void usnic_vnic_release_resources(struct usnic_vnic *vnic)
{
        int i;
        struct pci_dev *pdev;
        enum usnic_vnic_res_type res_type;

        pdev = usnic_vnic_get_pdev(vnic);

        for (res_type = USNIC_VNIC_RES_TYPE_EOL + 1;
                        res_type < USNIC_VNIC_RES_TYPE_MAX; res_type++)
                usnic_vnic_free_res_chunk(&vnic->chunks[res_type]);

        vnic_dev_unregister(vnic->vdev);

        for (i = 0; i < ARRAY_SIZE(vnic->bar); i++) {
                if (!(pci_resource_flags(pdev, i) & IORESOURCE_MEM))
                        continue;
                iounmap(vnic->bar[i].vaddr);
        }
}

struct usnic_vnic *usnic_vnic_alloc(struct pci_dev *pdev)
{
        struct usnic_vnic *vnic;
        int err = 0;

        if (!pci_is_enabled(pdev)) {
                usnic_err("PCI dev %s is disabled\n", pci_name(pdev));
                return ERR_PTR(-EINVAL);
        }

        vnic = kzalloc_obj(*vnic);
        if (!vnic)
                return ERR_PTR(-ENOMEM);

        spin_lock_init(&vnic->res_lock);

        err = usnic_vnic_discover_resources(pdev, vnic);
        if (err) {
                usnic_err("Failed to discover %s resources with err %d\n",
                                pci_name(pdev), err);
                goto out_free_vnic;
        }

        usnic_dbg("Allocated vnic for %s\n", usnic_vnic_pci_name(vnic));

        return vnic;

out_free_vnic:
        kfree(vnic);

        return ERR_PTR(err);
}

void usnic_vnic_free(struct usnic_vnic *vnic)
{
        usnic_vnic_release_resources(vnic);
        kfree(vnic);
}