/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (C) 2012-2014 Matteo Landi
 * Copyright (C) 2012-2016 Luigi Rizzo
 * Copyright (C) 2012-2016 Giuseppe Lettieri
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *   1. Redistributions of source code must retain the above copyright
 *      notice, this list of conditions and the following disclaimer.
 *   2. 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.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#ifdef linux
#include "bsd_glue.h"
#endif /* linux */

#ifdef __APPLE__
#include "osx_glue.h"
#endif /* __APPLE__ */

#ifdef __FreeBSD__
#include <sys/types.h>
#include <sys/domainset.h>
#include <sys/malloc.h>
#include <sys/kernel.h>         /* MALLOC_DEFINE */
#include <sys/proc.h>
#include <vm/vm.h>      /* vtophys */
#include <vm/pmap.h>    /* vtophys */
#include <sys/socket.h> /* sockaddrs */
#include <sys/selinfo.h>
#include <sys/sysctl.h>
#include <net/if.h>
#include <net/if_var.h>
#include <net/vnet.h>
#include <machine/bus.h>        /* bus_dmamap_* */

/* M_NETMAP only used in here */
MALLOC_DECLARE(M_NETMAP);
MALLOC_DEFINE(M_NETMAP, "netmap", "Network memory map");

#endif /* __FreeBSD__ */

#ifdef _WIN32
#include <win_glue.h>
#endif

#include <net/netmap.h>
#include <dev/netmap/netmap_kern.h>
#include <net/netmap_virt.h>
#include "netmap_mem2.h"

#ifdef _WIN32_USE_SMALL_GENERIC_DEVICES_MEMORY
#define NETMAP_BUF_MAX_NUM  8*4096      /* if too big takes too much time to allocate */
#else
#define NETMAP_BUF_MAX_NUM 20*4096*2    /* large machine */
#endif

#define NETMAP_POOL_MAX_NAMSZ   32


enum {
        NETMAP_IF_POOL   = 0,
        NETMAP_RING_POOL,
        NETMAP_BUF_POOL,
        NETMAP_POOLS_NR
};


struct netmap_obj_params {
        u_int size;
        u_int num;

        u_int last_size;
        u_int last_num;
};

struct netmap_obj_pool {
        char name[NETMAP_POOL_MAX_NAMSZ];       /* name of the allocator */

        /* ---------------------------------------------------*/
        /* these are only meaningful if the pool is finalized */
        /* (see 'finalized' field in netmap_mem_d)            */
        size_t memtotal;        /* actual total memory space */

        struct lut_entry *lut;  /* virt,phys addresses, objtotal entries */
        uint32_t *bitmap;       /* one bit per buffer, 1 means free */
        uint32_t *invalid_bitmap;/* one bit per buffer, 1 means invalid */
        uint32_t bitmap_slots;  /* number of uint32 entries in bitmap */

        u_int objtotal;         /* actual total number of objects. */
        u_int numclusters;      /* actual number of clusters */
        u_int objfree;          /* number of free objects. */

        int     alloc_done;     /* we have allocated the memory */
        /* ---------------------------------------------------*/

        /* limits */
        u_int objminsize;       /* minimum object size */
        u_int objmaxsize;       /* maximum object size */
        u_int nummin;           /* minimum number of objects */
        u_int nummax;           /* maximum number of objects */

        /* these are changed only by config */
        u_int _objtotal;        /* total number of objects */
        u_int _objsize;         /* object size */
        u_int _clustsize;       /* cluster size */
        u_int _clustentries;    /* objects per cluster */
        u_int _numclusters;     /* number of clusters */

        /* requested values */
        u_int r_objtotal;
        u_int r_objsize;
};

#define NMA_LOCK_T              NM_MTX_T
#define NMA_LOCK_INIT(n)        NM_MTX_INIT((n)->nm_mtx)
#define NMA_LOCK_DESTROY(n)     NM_MTX_DESTROY((n)->nm_mtx)
#define NMA_LOCK(n)             NM_MTX_LOCK((n)->nm_mtx)
#define NMA_SPINLOCK(n)         NM_MTX_SPINLOCK((n)->nm_mtx)
#define NMA_UNLOCK(n)           NM_MTX_UNLOCK((n)->nm_mtx)

struct netmap_mem_ops {
        int (*nmd_get_lut)(struct netmap_mem_d *, struct netmap_lut*);
        int  (*nmd_get_info)(struct netmap_mem_d *, uint64_t *size,
                        u_int *memflags, uint16_t *id);

        vm_paddr_t (*nmd_ofstophys)(struct netmap_mem_d *, vm_ooffset_t);
        int (*nmd_config)(struct netmap_mem_d *);
        int (*nmd_finalize)(struct netmap_mem_d *, struct netmap_adapter *);
        void (*nmd_deref)(struct netmap_mem_d *, struct netmap_adapter *);
        ssize_t  (*nmd_if_offset)(struct netmap_mem_d *, const void *vaddr);
        void (*nmd_delete)(struct netmap_mem_d *);

        struct netmap_if * (*nmd_if_new)(struct netmap_mem_d *,
                        struct netmap_adapter *, struct netmap_priv_d *);
        void (*nmd_if_delete)(struct netmap_mem_d *,
                        struct netmap_adapter *, struct netmap_if *);
        int  (*nmd_rings_create)(struct netmap_mem_d *,
                        struct netmap_adapter *);
        void (*nmd_rings_delete)(struct netmap_mem_d *,
                        struct netmap_adapter *);
};

struct netmap_mem_d {
        NMA_LOCK_T nm_mtx;  /* protect the allocator */
        size_t nm_totalsize; /* shorthand */

        u_int flags;
#define NETMAP_MEM_FINALIZED    0x1     /* preallocation done */
#define NETMAP_MEM_HIDDEN       0x8     /* being prepared */
#define NETMAP_MEM_NOMAP        0x10    /* do not map/unmap pdevs */
        int lasterr;            /* last error for curr config */
        int active;             /* active users */
        int refcount;
        /* the three allocators */
        struct netmap_obj_pool pools[NETMAP_POOLS_NR];

        nm_memid_t nm_id;       /* allocator identifier */
        int nm_grp;             /* iommu group id */
        int nm_numa_domain;     /* local NUMA domain */

        /* list of all existing allocators, sorted by nm_id */
        struct netmap_mem_d *prev, *next;

        const struct netmap_mem_ops *ops;

        struct netmap_obj_params params[NETMAP_POOLS_NR];

#define NM_MEM_NAMESZ   16
        char name[NM_MEM_NAMESZ];
};

int
netmap_mem_get_lut(struct netmap_mem_d *nmd, struct netmap_lut *lut)
{
        int rv;

        NMA_LOCK(nmd);
        rv = nmd->ops->nmd_get_lut(nmd, lut);
        NMA_UNLOCK(nmd);

        return rv;
}

int
netmap_mem_get_info(struct netmap_mem_d *nmd, uint64_t *size,
                u_int *memflags, nm_memid_t *memid)
{
        int rv;

        NMA_LOCK(nmd);
        rv = nmd->ops->nmd_get_info(nmd, size, memflags, memid);
        NMA_UNLOCK(nmd);

        return rv;
}

vm_paddr_t
netmap_mem_ofstophys(struct netmap_mem_d *nmd, vm_ooffset_t off)
{
        vm_paddr_t pa;

#if defined(__FreeBSD__)
        /* This function is called by netmap_dev_pager_fault(), which holds a
         * non-sleepable lock since FreeBSD 12. Since we cannot sleep, we
         * spin on the trylock. */
        NMA_SPINLOCK(nmd);
#else
        NMA_LOCK(nmd);
#endif
        pa = nmd->ops->nmd_ofstophys(nmd, off);
        NMA_UNLOCK(nmd);

        return pa;
}

static int
netmap_mem_config(struct netmap_mem_d *nmd)
{
        if (nmd->active) {
                /* already in use. Not fatal, but we
                 * cannot change the configuration
                 */
                return 0;
        }

        return nmd->ops->nmd_config(nmd);
}

ssize_t
netmap_mem_if_offset(struct netmap_mem_d *nmd, const void *off)
{
        ssize_t rv;

        NMA_LOCK(nmd);
        rv = nmd->ops->nmd_if_offset(nmd, off);
        NMA_UNLOCK(nmd);

        return rv;
}

static void
netmap_mem_delete(struct netmap_mem_d *nmd)
{
        nmd->ops->nmd_delete(nmd);
}

struct netmap_if *
netmap_mem_if_new(struct netmap_adapter *na, struct netmap_priv_d *priv)
{
        struct netmap_if *nifp;
        struct netmap_mem_d *nmd = na->nm_mem;

        NMA_LOCK(nmd);
        nifp = nmd->ops->nmd_if_new(nmd, na, priv);
        NMA_UNLOCK(nmd);

        return nifp;
}

void
netmap_mem_if_delete(struct netmap_adapter *na, struct netmap_if *nif)
{
        struct netmap_mem_d *nmd = na->nm_mem;

        NMA_LOCK(nmd);
        nmd->ops->nmd_if_delete(nmd, na, nif);
        NMA_UNLOCK(nmd);
}

int
netmap_mem_rings_create(struct netmap_adapter *na)
{
        int rv;
        struct netmap_mem_d *nmd = na->nm_mem;

        NMA_LOCK(nmd);
        rv = nmd->ops->nmd_rings_create(nmd, na);
        NMA_UNLOCK(nmd);

        return rv;
}

void
netmap_mem_rings_delete(struct netmap_adapter *na)
{
        struct netmap_mem_d *nmd = na->nm_mem;

        NMA_LOCK(nmd);
        nmd->ops->nmd_rings_delete(nmd, na);
        NMA_UNLOCK(nmd);
}

static int netmap_mem_map(struct netmap_obj_pool *, struct netmap_adapter *);
static int netmap_mem_unmap(struct netmap_obj_pool *, struct netmap_adapter *);
static int nm_mem_check_group(struct netmap_mem_d *, void *);
static void nm_mem_release_id(struct netmap_mem_d *);

nm_memid_t
netmap_mem_get_id(struct netmap_mem_d *nmd)
{
        return nmd->nm_id;
}

#ifdef NM_DEBUG_MEM_PUTGET
#define NM_DBG_REFC(nmd, func, line)    \
        nm_prinf("%s:%d mem[%d:%d] -> %d", func, line, (nmd)->nm_id, (nmd)->nm_grp, (nmd)->refcount);
#else
#define NM_DBG_REFC(nmd, func, line)
#endif

/* circular list of all existing allocators */
static struct netmap_mem_d *netmap_last_mem_d = &nm_mem;
static NM_MTX_T nm_mem_list_lock;

struct netmap_mem_d *
__netmap_mem_get(struct netmap_mem_d *nmd, const char *func, int line)
{
        NM_MTX_LOCK(nm_mem_list_lock);
        nmd->refcount++;
        NM_DBG_REFC(nmd, func, line);
        NM_MTX_UNLOCK(nm_mem_list_lock);
        return nmd;
}

void
__netmap_mem_put(struct netmap_mem_d *nmd, const char *func, int line)
{
        int last;
        NM_MTX_LOCK(nm_mem_list_lock);
        last = (--nmd->refcount == 0);
        if (last)
                nm_mem_release_id(nmd);
        NM_DBG_REFC(nmd, func, line);
        NM_MTX_UNLOCK(nm_mem_list_lock);
        if (last)
                netmap_mem_delete(nmd);
}

int
netmap_mem_finalize(struct netmap_mem_d *nmd, struct netmap_adapter *na)
{
        int lasterr = 0;
        if (nm_mem_check_group(nmd, na->pdev) < 0) {
                return ENOMEM;
        }

        NMA_LOCK(nmd);

        if (netmap_mem_config(nmd))
                goto out;

        nmd->active++;

        nmd->lasterr = nmd->ops->nmd_finalize(nmd, na);

        if (!nmd->lasterr && !(nmd->flags & NETMAP_MEM_NOMAP)) {
                nmd->lasterr = netmap_mem_map(&nmd->pools[NETMAP_BUF_POOL], na);
        }

out:
        lasterr = nmd->lasterr;
        NMA_UNLOCK(nmd);

        if (lasterr)
                netmap_mem_deref(nmd, na);

        return lasterr;
}

static int
nm_isset(uint32_t *bitmap, u_int i)
{
        return bitmap[ (i>>5) ] & ( 1U << (i & 31U) );
}


static int
netmap_init_obj_allocator_bitmap(struct netmap_obj_pool *p)
{
        u_int n, j;

        if (p->bitmap == NULL) {
                /* Allocate the bitmap */
                n = (p->objtotal + 31) / 32;
                p->bitmap = nm_os_malloc(sizeof(p->bitmap[0]) * n);
                if (p->bitmap == NULL) {
                        nm_prerr("Unable to create bitmap (%d entries) for allocator '%s'", (int)n,
                            p->name);
                        return ENOMEM;
                }
                p->bitmap_slots = n;
        } else {
                memset(p->bitmap, 0, p->bitmap_slots * sizeof(p->bitmap[0]));
        }

        p->objfree = 0;
        /*
         * Set all the bits in the bitmap that have
         * corresponding buffers to 1 to indicate they are
         * free.
         */
        for (j = 0; j < p->objtotal; j++) {
                if (p->invalid_bitmap && nm_isset(p->invalid_bitmap, j)) {
                        if (netmap_debug & NM_DEBUG_MEM)
                                nm_prinf("skipping %s %d", p->name, j);
                        continue;
                }
                p->bitmap[ (j>>5) ] |=  ( 1U << (j & 31U) );
                p->objfree++;
        }

        if (netmap_verbose)
                nm_prinf("%s free %u", p->name, p->objfree);
        if (p->objfree == 0) {
                if (netmap_verbose)
                        nm_prerr("%s: no objects available", p->name);
                return ENOMEM;
        }

        return 0;
}

static int
netmap_mem_init_bitmaps(struct netmap_mem_d *nmd)
{
        int i, error = 0;

        for (i = 0; i < NETMAP_POOLS_NR; i++) {
                struct netmap_obj_pool *p = &nmd->pools[i];

                error = netmap_init_obj_allocator_bitmap(p);
                if (error)
                        return error;
        }

        /*
         * buffers 0 and 1 are reserved
         */
        if (nmd->pools[NETMAP_BUF_POOL].objfree < 2) {
                nm_prerr("%s: not enough buffers", nmd->pools[NETMAP_BUF_POOL].name);
                return ENOMEM;
        }

        nmd->pools[NETMAP_BUF_POOL].objfree -= 2;
        if (nmd->pools[NETMAP_BUF_POOL].bitmap) {
                /* XXX This check is a workaround that prevents a
                 * NULL pointer crash which currently happens only
                 * with ptnetmap guests.
                 * Removed shared-info --> is the bug still there? */
                nmd->pools[NETMAP_BUF_POOL].bitmap[0] = ~3U;
        }
        return 0;
}

int
netmap_mem_deref(struct netmap_mem_d *nmd, struct netmap_adapter *na)
{
        int last_user = 0;
        NMA_LOCK(nmd);
        if (na->active_fds <= 0 && !(nmd->flags & NETMAP_MEM_NOMAP))
                netmap_mem_unmap(&nmd->pools[NETMAP_BUF_POOL], na);
        if (nmd->active == 1) {
                last_user = 1;
                /*
                 * Reset the allocator when it falls out of use so that any
                 * pool resources leaked by unclean application exits are
                 * reclaimed.
                 */
                netmap_mem_init_bitmaps(nmd);
        }
        nmd->ops->nmd_deref(nmd, na);

        nmd->active--;
        if (last_user) {
                nmd->lasterr = 0;
        }

        NMA_UNLOCK(nmd);
        return last_user;
}


/* accessor functions */
static int
netmap_mem2_get_lut(struct netmap_mem_d *nmd, struct netmap_lut *lut)
{
        lut->lut = nmd->pools[NETMAP_BUF_POOL].lut;
#ifdef __FreeBSD__
        lut->plut = lut->lut;
#endif
        lut->objtotal = nmd->pools[NETMAP_BUF_POOL].objtotal;
        lut->objsize = nmd->pools[NETMAP_BUF_POOL]._objsize;

        return 0;
}

static struct netmap_obj_params netmap_min_priv_params[NETMAP_POOLS_NR] = {
        [NETMAP_IF_POOL] = {
                .size = 1024,
                .num  = 2,
        },
        [NETMAP_RING_POOL] = {
                .size = 5*PAGE_SIZE,
                .num  = 4,
        },
        [NETMAP_BUF_POOL] = {
                .size = 2048,
                .num  = 4098,
        },
};


/*
 * nm_mem is the memory allocator used for all physical interfaces
 * running in netmap mode.
 * Virtual (VALE) ports will have each its own allocator.
 */
extern const struct netmap_mem_ops netmap_mem_global_ops; /* forward */
struct netmap_mem_d nm_mem = {  /* Our memory allocator. */
        .pools = {
                [NETMAP_IF_POOL] = {
                        .name   = "netmap_if",
                        .objminsize = sizeof(struct netmap_if),
                        .objmaxsize = 4096,
                        .nummin     = 10,       /* don't be stingy */
                        .nummax     = 10000,    /* XXX very large */
                },
                [NETMAP_RING_POOL] = {
                        .name   = "netmap_ring",
                        .objminsize = sizeof(struct netmap_ring),
                        .objmaxsize = 32*PAGE_SIZE,
                        .nummin     = 2,
                        .nummax     = 1024,
                },
                [NETMAP_BUF_POOL] = {
                        .name   = "netmap_buf",
                        .objminsize = 64,
                        .objmaxsize = 65536,
                        .nummin     = 4,
                        .nummax     = 1000000, /* one million! */
                },
        },

        .params = {
                [NETMAP_IF_POOL] = {
                        .size = 1024,
                        .num  = 100,
                },
                [NETMAP_RING_POOL] = {
                        .size = 9*PAGE_SIZE,
                        .num  = 200,
                },
                [NETMAP_BUF_POOL] = {
                        .size = 2048,
                        .num  = NETMAP_BUF_MAX_NUM,
                },
        },

        .nm_id = 1,
        .nm_grp = -1,
        .nm_numa_domain = -1,

        .prev = &nm_mem,
        .next = &nm_mem,

        .ops = &netmap_mem_global_ops,

        .name = "1"
};

static struct netmap_mem_d nm_mem_blueprint;

/* blueprint for the private memory allocators */
/* XXX clang is not happy about using name as a print format */
static const struct netmap_mem_d nm_blueprint = {
        .pools = {
                [NETMAP_IF_POOL] = {
                        .name   = "%s_if",
                        .objminsize = sizeof(struct netmap_if),
                        .objmaxsize = 4096,
                        .nummin     = 1,
                        .nummax     = 100,
                },
                [NETMAP_RING_POOL] = {
                        .name   = "%s_ring",
                        .objminsize = sizeof(struct netmap_ring),
                        .objmaxsize = 32*PAGE_SIZE,
                        .nummin     = 2,
                        .nummax     = 1024,
                },
                [NETMAP_BUF_POOL] = {
                        .name   = "%s_buf",
                        .objminsize = 64,
                        .objmaxsize = 65536,
                        .nummin     = 4,
                        .nummax     = 1000000, /* one million! */
                },
        },

        .nm_grp = -1,
        .nm_numa_domain = -1,

        .flags = NETMAP_MEM_PRIVATE,

        .ops = &netmap_mem_global_ops,
};

/* memory allocator related sysctls */

#define STRINGIFY(x) #x

#define DECLARE_SYSCTLS(id, name)                               \
        SYSBEGIN(mem2_ ## name);                                \
        SYSCTL_INT(_dev_netmap, OID_AUTO, name##_size,          \
            CTLFLAG_RWTUN, &nm_mem.params[id].size, 0,          \
            "Requested size of netmap " STRINGIFY(name) "s");   \
        SYSCTL_INT(_dev_netmap, OID_AUTO, name##_curr_size,     \
            CTLFLAG_RD, &nm_mem.pools[id]._objsize, 0,          \
            "Current size of netmap " STRINGIFY(name) "s");     \
        SYSCTL_INT(_dev_netmap, OID_AUTO, name##_num,           \
            CTLFLAG_RWTUN, &nm_mem.params[id].num, 0,           \
            "Requested number of netmap " STRINGIFY(name) "s"); \
        SYSCTL_INT(_dev_netmap, OID_AUTO, name##_curr_num,      \
            CTLFLAG_RD, &nm_mem.pools[id].objtotal, 0,          \
            "Current number of netmap " STRINGIFY(name) "s");   \
        SYSCTL_INT(_dev_netmap, OID_AUTO, priv_##name##_size,   \
            CTLFLAG_RWTUN, &netmap_min_priv_params[id].size, 0, \
            "Default size of private netmap " STRINGIFY(name) "s"); \
        SYSCTL_INT(_dev_netmap, OID_AUTO, priv_##name##_num,    \
            CTLFLAG_RWTUN, &netmap_min_priv_params[id].num, 0,  \
            "Default number of private netmap " STRINGIFY(name) "s"); \
        SYSEND

SYSCTL_DECL(_dev_netmap);
DECLARE_SYSCTLS(NETMAP_IF_POOL, if);
DECLARE_SYSCTLS(NETMAP_RING_POOL, ring);
DECLARE_SYSCTLS(NETMAP_BUF_POOL, buf);

int netmap_port_numa_affinity = 0;
SYSCTL_INT(_dev_netmap, OID_AUTO, port_numa_affinity,
    CTLFLAG_RDTUN, &netmap_port_numa_affinity, 0,
    "Use NUMA-local memory for memory pools when possible");

/* call with nm_mem_list_lock held */
static int
nm_mem_assign_id_locked(struct netmap_mem_d *nmd, int grp_id, int domain)
{
        nm_memid_t id;
        struct netmap_mem_d *scan = netmap_last_mem_d;
        int error = ENOMEM;

        do {
                /* we rely on unsigned wrap around */
                id = scan->nm_id + 1;
                if (id == 0) /* reserve 0 as error value */
                        id = 1;
                scan = scan->next;
                if (id != scan->nm_id) {
                        nmd->nm_id = id;
                        nmd->nm_grp = grp_id;
                        nmd->nm_numa_domain = domain;
                        nmd->prev = scan->prev;
                        nmd->next = scan;
                        scan->prev->next = nmd;
                        scan->prev = nmd;
                        netmap_last_mem_d = nmd;
                        nmd->refcount = 1;
                        NM_DBG_REFC(nmd, __FUNCTION__, __LINE__);
                        error = 0;
                        break;
                }
        } while (scan != netmap_last_mem_d);

        return error;
}

/* call with nm_mem_list_lock *not* held */
static int
nm_mem_assign_id(struct netmap_mem_d *nmd, int grp_id)
{
        int ret;

        NM_MTX_LOCK(nm_mem_list_lock);
        ret = nm_mem_assign_id_locked(nmd, grp_id, -1);
        NM_MTX_UNLOCK(nm_mem_list_lock);

        return ret;
}

/* call with nm_mem_list_lock held */
static void
nm_mem_release_id(struct netmap_mem_d *nmd)
{
        nmd->prev->next = nmd->next;
        nmd->next->prev = nmd->prev;

        if (netmap_last_mem_d == nmd)
                netmap_last_mem_d = nmd->prev;

        nmd->prev = nmd->next = NULL;
}

struct netmap_mem_d *
netmap_mem_find(nm_memid_t id)
{
        struct netmap_mem_d *nmd;

        NM_MTX_LOCK(nm_mem_list_lock);
        nmd = netmap_last_mem_d;
        do {
                if (!(nmd->flags & NETMAP_MEM_HIDDEN) && nmd->nm_id == id) {
                        nmd->refcount++;
                        NM_DBG_REFC(nmd, __FUNCTION__, __LINE__);
                        NM_MTX_UNLOCK(nm_mem_list_lock);
                        return nmd;
                }
                nmd = nmd->next;
        } while (nmd != netmap_last_mem_d);
        NM_MTX_UNLOCK(nm_mem_list_lock);
        return NULL;
}

static int
nm_mem_check_group(struct netmap_mem_d *nmd, void *dev)
{
        int err = 0, id;

        /* Skip not hw adapters.
         * Vale port can use particular allocator through vale-ctl -m option
         */
        if (!dev)
                return 0;
        id = nm_iommu_group_id(dev);
        if (netmap_debug & NM_DEBUG_MEM)
                nm_prinf("iommu_group %d", id);

        NMA_LOCK(nmd);

        if (nmd->nm_grp != id) {
                if (netmap_verbose)
                        nm_prerr("iommu group mismatch: %d vs %d",
                                        nmd->nm_grp, id);
                nmd->lasterr = err = ENOMEM;
        }

        NMA_UNLOCK(nmd);
        return err;
}

static struct lut_entry *
nm_alloc_lut(u_int nobj)
{
        size_t n = sizeof(struct lut_entry) * nobj;
        struct lut_entry *lut;
#ifdef linux
        lut = vmalloc(n);
#else
        lut = nm_os_malloc(n);
#endif
        return lut;
}

static void
nm_free_lut(struct lut_entry *lut, u_int objtotal)
{
        bzero(lut, sizeof(struct lut_entry) * objtotal);
#ifdef linux
        vfree(lut);
#else
        nm_os_free(lut);
#endif
}

#if defined(linux) || defined(_WIN32)
static struct plut_entry *
nm_alloc_plut(u_int nobj)
{
        size_t n = sizeof(struct plut_entry) * nobj;
        struct plut_entry *lut;
        lut = vmalloc(n);
        return lut;
}

static void
nm_free_plut(struct plut_entry * lut)
{
        vfree(lut);
}
#endif /* linux or _WIN32 */


/*
 * First, find the allocator that contains the requested offset,
 * then locate the cluster through a lookup table.
 */
static vm_paddr_t
netmap_mem2_ofstophys(struct netmap_mem_d* nmd, vm_ooffset_t offset)
{
        int i;
        vm_ooffset_t o = offset;
        vm_paddr_t pa;
        struct netmap_obj_pool *p;

        p = nmd->pools;

        for (i = 0; i < NETMAP_POOLS_NR; offset -= p[i].memtotal, i++) {
                if (offset >= p[i].memtotal)
                        continue;
                // now lookup the cluster's address
#ifndef _WIN32
                pa = vtophys(p[i].lut[offset / p[i]._objsize].vaddr) +
                        offset % p[i]._objsize;
#else
                pa = vtophys(p[i].lut[offset / p[i]._objsize].vaddr);
                pa.QuadPart += offset % p[i]._objsize;
#endif
                return pa;
        }
        /* this is only in case of errors */
        nm_prerr("invalid ofs 0x%x out of 0x%zx 0x%zx 0x%zx", (u_int)o,
                p[NETMAP_IF_POOL].memtotal,
                p[NETMAP_IF_POOL].memtotal
                        + p[NETMAP_RING_POOL].memtotal,
                p[NETMAP_IF_POOL].memtotal
                        + p[NETMAP_RING_POOL].memtotal
                        + p[NETMAP_BUF_POOL].memtotal);
#ifndef _WIN32
        return 0; /* bad address */
#else
        vm_paddr_t res;
        res.QuadPart = 0;
        return res;
#endif
}

#ifdef _WIN32

/*
 * win32_build_virtual_memory_for_userspace
 *
 * This function get all the object making part of the pools and maps
 * a contiguous virtual memory space for the userspace
 * It works this way
 * 1 - allocate a Memory Descriptor List wide as the sum
 *              of the memory needed for the pools
 * 2 - cycle all the objects in every pool and for every object do
 *
 *              2a - cycle all the objects in every pool, get the list
 *                              of the physical address descriptors
 *              2b - calculate the offset in the array of pages descriptor in the
 *                              main MDL
 *              2c - copy the descriptors of the object in the main MDL
 *
 * 3 - return the resulting MDL that needs to be mapped in userland
 *
 * In this way we will have an MDL that describes all the memory for the
 * objects in a single object
*/

PMDL
win32_build_user_vm_map(struct netmap_mem_d* nmd)
{
        u_int memflags, ofs = 0;
        PMDL mainMdl, tempMdl;
        uint64_t memsize;
        int i, j;

        if (netmap_mem_get_info(nmd, &memsize, &memflags, NULL)) {
                nm_prerr("memory not finalised yet");
                return NULL;
        }

        mainMdl = IoAllocateMdl(NULL, memsize, FALSE, FALSE, NULL);
        if (mainMdl == NULL) {
                nm_prerr("failed to allocate mdl");
                return NULL;
        }

        NMA_LOCK(nmd);
        for (i = 0; i < NETMAP_POOLS_NR; i++) {
                struct netmap_obj_pool *p = &nmd->pools[i];
                int clsz = p->_clustsize;
                int clobjs = p->_clustentries; /* objects per cluster */
                int mdl_len = sizeof(PFN_NUMBER) * BYTES_TO_PAGES(clsz);
                PPFN_NUMBER pSrc, pDst;

                /* each pool has a different cluster size so we need to reallocate */
                tempMdl = IoAllocateMdl(p->lut[0].vaddr, clsz, FALSE, FALSE, NULL);
                if (tempMdl == NULL) {
                        NMA_UNLOCK(nmd);
                        nm_prerr("fail to allocate tempMdl");
                        IoFreeMdl(mainMdl);
                        return NULL;
                }
                pSrc = MmGetMdlPfnArray(tempMdl);
                /* create one entry per cluster, the lut[] has one entry per object */
                for (j = 0; j < p->numclusters; j++, ofs += clsz) {
                        pDst = &MmGetMdlPfnArray(mainMdl)[BYTES_TO_PAGES(ofs)];
                        MmInitializeMdl(tempMdl, p->lut[j*clobjs].vaddr, clsz);
                        MmBuildMdlForNonPagedPool(tempMdl); /* compute physical page addresses */
                        RtlCopyMemory(pDst, pSrc, mdl_len); /* copy the page descriptors */
                        mainMdl->MdlFlags = tempMdl->MdlFlags; /* XXX what is in here ? */
                }
                IoFreeMdl(tempMdl);
        }
        NMA_UNLOCK(nmd);
        return mainMdl;
}

#endif /* _WIN32 */

/*
 * helper function for OS-specific mmap routines (currently only windows).
 * Given an nmd and a pool index, returns the cluster size and number of clusters.
 * Returns 0 if memory is finalised and the pool is valid, otherwise 1.
 * It should be called under NMA_LOCK(nmd) otherwise the underlying info can change.
 */

int
netmap_mem2_get_pool_info(struct netmap_mem_d* nmd, u_int pool, u_int *clustsize, u_int *numclusters)
{
        if (!nmd || !clustsize || !numclusters || pool >= NETMAP_POOLS_NR)
                return 1; /* invalid arguments */
        // NMA_LOCK_ASSERT(nmd);
        if (!(nmd->flags & NETMAP_MEM_FINALIZED)) {
                *clustsize = *numclusters = 0;
                return 1; /* not ready yet */
        }
        *clustsize = nmd->pools[pool]._clustsize;
        *numclusters = nmd->pools[pool].numclusters;
        return 0; /* success */
}

static int
netmap_mem2_get_info(struct netmap_mem_d* nmd, uint64_t* size,
                        u_int *memflags, nm_memid_t *id)
{
        int error = 0;
        error = netmap_mem_config(nmd);
        if (error)
                goto out;
        if (size) {
                if (nmd->flags & NETMAP_MEM_FINALIZED) {
                        *size = nmd->nm_totalsize;
                } else {
                        int i;
                        *size = 0;
                        for (i = 0; i < NETMAP_POOLS_NR; i++) {
                                struct netmap_obj_pool *p = nmd->pools + i;
                                *size += ((size_t)p->_numclusters * (size_t)p->_clustsize);
                        }
                }
        }
        if (memflags)
                *memflags = nmd->flags;
        if (id)
                *id = nmd->nm_id;
out:
        return error;
}

/*
 * we store objects by kernel address, need to find the offset
 * within the pool to export the value to userspace.
 * Algorithm: scan until we find the cluster, then add the
 * actual offset in the cluster
 */
static ssize_t
netmap_obj_offset(struct netmap_obj_pool *p, const void *vaddr)
{
        int i, k = p->_clustentries, n = p->objtotal;
        ssize_t ofs = 0;

        for (i = 0; i < n; i += k, ofs += p->_clustsize) {
                const char *base = p->lut[i].vaddr;
                ssize_t relofs = (const char *) vaddr - base;

                if (relofs < 0 || relofs >= p->_clustsize)
                        continue;

                ofs = ofs + relofs;
                nm_prdis("%s: return offset %d (cluster %d) for pointer %p",
                    p->name, ofs, i, vaddr);
                return ofs;
        }
        nm_prerr("address %p is not contained inside any cluster (%s)",
            vaddr, p->name);
        return 0; /* An error occurred */
}

/* Helper functions which convert virtual addresses to offsets */
#define netmap_if_offset(n, v)                                  \
        netmap_obj_offset(&(n)->pools[NETMAP_IF_POOL], (v))

#define netmap_ring_offset(n, v)                                \
    ((n)->pools[NETMAP_IF_POOL].memtotal +                      \
        netmap_obj_offset(&(n)->pools[NETMAP_RING_POOL], (v)))

static ssize_t
netmap_mem2_if_offset(struct netmap_mem_d *nmd, const void *addr)
{
        return netmap_if_offset(nmd, addr);
}

/*
 * report the index, and use start position as a hint,
 * otherwise buffer allocation becomes terribly expensive.
 */
static void *
netmap_obj_malloc(struct netmap_obj_pool *p, u_int len, uint32_t *start, uint32_t *index)
{
        uint32_t i = 0;                 /* index in the bitmap */
        uint32_t mask, j = 0;           /* slot counter */
        void *vaddr = NULL;

        if (len > p->_objsize) {
                nm_prerr("%s request size %d too large", p->name, len);
                return NULL;
        }

        if (p->objfree == 0) {
                nm_prerr("no more %s objects", p->name);
                return NULL;
        }
        if (start)
                i = *start;

        /* termination is guaranteed by p->free, but better check bounds on i */
        while (vaddr == NULL && i < p->bitmap_slots)  {
                uint32_t cur = p->bitmap[i];
                if (cur == 0) { /* bitmask is fully used */
                        i++;
                        continue;
                }
                /* locate a slot */
                for (j = 0, mask = 1; (cur & mask) == 0; j++, mask <<= 1)
                        ;

                p->bitmap[i] &= ~mask; /* mark object as in use */
                p->objfree--;

                vaddr = p->lut[i * 32 + j].vaddr;
                if (index)
                        *index = i * 32 + j;
        }
        nm_prdis("%s allocator: allocated object @ [%d][%d]: vaddr %p",p->name, i, j, vaddr);

        if (start)
                *start = i;
        return vaddr;
}


/*
 * free by index, not by address.
 * XXX should we also cleanup the content ?
 */
static int
netmap_obj_free(struct netmap_obj_pool *p, uint32_t j)
{
        uint32_t *ptr, mask;

        if (j >= p->objtotal) {
                nm_prerr("invalid index %u, max %u", j, p->objtotal);
                return 1;
        }
        ptr = &p->bitmap[j / 32];
        mask = (1 << (j % 32));
        if (*ptr & mask) {
                nm_prerr("ouch, double free on buffer %d", j);
                return 1;
        } else {
                *ptr |= mask;
                p->objfree++;
                return 0;
        }
}

/*
 * free by address. This is slow but is only used for a few
 * objects (rings, nifp)
 */
static void
netmap_obj_free_va(struct netmap_obj_pool *p, void *vaddr)
{
        u_int i, j, n = p->numclusters;

        for (i = 0, j = 0; i < n; i++, j += p->_clustentries) {
                void *base = p->lut[i * p->_clustentries].vaddr;
                ssize_t relofs = (ssize_t) vaddr - (ssize_t) base;

                /* Given address, is out of the scope of the current cluster.*/
                if (base == NULL || vaddr < base || relofs >= p->_clustsize)
                        continue;

                j = j + relofs / p->_objsize;
                /* KASSERT(j != 0, ("Cannot free object 0")); */
                netmap_obj_free(p, j);
                return;
        }
        nm_prerr("address %p is not contained inside any cluster (%s)",
            vaddr, p->name);
}

unsigned
netmap_mem_bufsize(struct netmap_mem_d *nmd)
{
        return nmd->pools[NETMAP_BUF_POOL]._objsize;
}

#define netmap_if_malloc(n, len)        netmap_obj_malloc(&(n)->pools[NETMAP_IF_POOL], len, NULL, NULL)
#define netmap_if_free(n, v)            netmap_obj_free_va(&(n)->pools[NETMAP_IF_POOL], (v))
#define netmap_ring_malloc(n, len)      netmap_obj_malloc(&(n)->pools[NETMAP_RING_POOL], len, NULL, NULL)
#define netmap_ring_free(n, v)          netmap_obj_free_va(&(n)->pools[NETMAP_RING_POOL], (v))
#define netmap_buf_malloc(n, _pos, _index)                      \
        netmap_obj_malloc(&(n)->pools[NETMAP_BUF_POOL], netmap_mem_bufsize(n), _pos, _index)


#if 0 /* currently unused */
/* Return the index associated to the given packet buffer */
#define netmap_buf_index(n, v)                                          \
    (netmap_obj_offset(&(n)->pools[NETMAP_BUF_POOL], (v)) / NETMAP_BDG_BUF_SIZE(n))
#endif

/*
 * allocate extra buffers in a linked list.
 * returns the actual number.
 */
uint32_t
netmap_extra_alloc(struct netmap_adapter *na, uint32_t *head, uint32_t n)
{
        struct netmap_mem_d *nmd = na->nm_mem;
        uint32_t i, pos = 0; /* opaque, scan position in the bitmap */

        NMA_LOCK(nmd);

        *head = 0;      /* default, 'null' index ie empty list */
        for (i = 0 ; i < n; i++) {
                uint32_t cur = *head;   /* save current head */
                uint32_t *p = netmap_buf_malloc(nmd, &pos, head);
                if (p == NULL) {
                        nm_prerr("no more buffers after %d of %d", i, n);
                        *head = cur; /* restore */
                        break;
                }
                nm_prdis(5, "allocate buffer %d -> %d", *head, cur);
                *p = cur; /* link to previous head */
        }

        NMA_UNLOCK(nmd);

        return i;
}

static void
netmap_extra_free(struct netmap_adapter *na, uint32_t head)
{
        struct lut_entry *lut = na->na_lut.lut;
        struct netmap_mem_d *nmd = na->nm_mem;
        struct netmap_obj_pool *p = &nmd->pools[NETMAP_BUF_POOL];
        uint32_t i, cur, *buf;

        nm_prdis("freeing the extra list");
        for (i = 0; head >=2 && head < p->objtotal; i++) {
                cur = head;
                buf = lut[head].vaddr;
                head = *buf;
                *buf = 0;
                if (netmap_obj_free(p, cur))
                        break;
        }
        if (head != 0)
                nm_prerr("breaking with head %d", head);
        if (netmap_debug & NM_DEBUG_MEM)
                nm_prinf("freed %d buffers", i);
}


/* Return nonzero on error */
static int
netmap_new_bufs(struct netmap_mem_d *nmd, struct netmap_slot *slot, u_int n)
{
        struct netmap_obj_pool *p = &nmd->pools[NETMAP_BUF_POOL];
        u_int i = 0;    /* slot counter */
        uint32_t pos = 0;       /* slot in p->bitmap */
        uint32_t index = 0;     /* buffer index */

        for (i = 0; i < n; i++) {
                void *vaddr = netmap_buf_malloc(nmd, &pos, &index);
                if (vaddr == NULL) {
                        nm_prerr("no more buffers after %d of %d", i, n);
                        goto cleanup;
                }
                slot[i].buf_idx = index;
                slot[i].len = p->_objsize;
                slot[i].flags = 0;
                slot[i].ptr = 0;
        }

        nm_prdis("%s: allocated %d buffers, %d available, first at %d", p->name, n, p->objfree, pos);
        return (0);

cleanup:
        while (i > 0) {
                i--;
                netmap_obj_free(p, slot[i].buf_idx);
        }
        bzero(slot, n * sizeof(slot[0]));
        return (ENOMEM);
}

static void
netmap_mem_set_ring(struct netmap_mem_d *nmd, struct netmap_slot *slot, u_int n, uint32_t index)
{
        struct netmap_obj_pool *p = &nmd->pools[NETMAP_BUF_POOL];
        u_int i;

        for (i = 0; i < n; i++) {
                slot[i].buf_idx = index;
                slot[i].len = p->_objsize;
                slot[i].flags = 0;
        }
}


static void
netmap_free_buf(struct netmap_mem_d *nmd, uint32_t i)
{
        struct netmap_obj_pool *p = &nmd->pools[NETMAP_BUF_POOL];

        if (i < 2 || i >= p->objtotal) {
                nm_prerr("Cannot free buf#%d: should be in [2, %d[", i, p->objtotal);
                return;
        }
        netmap_obj_free(p, i);
}


static void
netmap_free_bufs(struct netmap_mem_d *nmd, struct netmap_slot *slot, u_int n)
{
        u_int i;

        for (i = 0; i < n; i++) {
                if (slot[i].buf_idx > 1)
                        netmap_free_buf(nmd, slot[i].buf_idx);
        }
        nm_prdis("%s: released some buffers, available: %u",
                        p->name, p->objfree);
}

static void
netmap_reset_obj_allocator(struct netmap_obj_pool *p)
{

        if (p == NULL)
                return;
        if (p->bitmap)
                nm_os_free(p->bitmap);
        p->bitmap = NULL;
        if (p->invalid_bitmap)
                nm_os_free(p->invalid_bitmap);
        p->invalid_bitmap = NULL;
        if (!p->alloc_done) {
                /* allocation was done by somebody else.
                 * Let them clean up after themselves.
                 */
                return;
        }
        if (p->lut) {
                u_int i;

                /*
                 * Free each cluster allocated in
                 * netmap_finalize_obj_allocator().  The cluster start
                 * addresses are stored at multiples of p->_clusterentries
                 * in the lut.
                 */
                for (i = 0; i < p->objtotal; i += p->_clustentries) {
                        free(p->lut[i].vaddr, M_NETMAP);
                }
                nm_free_lut(p->lut, p->objtotal);
        }
        p->lut = NULL;
        p->objtotal = 0;
        p->memtotal = 0;
        p->numclusters = 0;
        p->objfree = 0;
        p->alloc_done = 0;
}

/*
 * Free all resources related to an allocator.
 */
static void
netmap_destroy_obj_allocator(struct netmap_obj_pool *p)
{
        if (p == NULL)
                return;
        netmap_reset_obj_allocator(p);
}

/*
 * We receive a request for objtotal objects, of size objsize each.
 * Internally we may round up both numbers, as we allocate objects
 * in small clusters multiple of the page size.
 * We need to keep track of objtotal and clustentries,
 * as they are needed when freeing memory.
 *
 * XXX note -- userspace needs the buffers to be contiguous,
 *      so we cannot afford gaps at the end of a cluster.
 */


/* call with NMA_LOCK held */
static int
netmap_config_obj_allocator(struct netmap_obj_pool *p, u_int objtotal, u_int objsize)
{
        int i;
        u_int clustsize;        /* the cluster size, multiple of page size */
        u_int clustentries;     /* how many objects per entry */

        /* we store the current request, so we can
         * detect configuration changes later */
        p->r_objtotal = objtotal;
        p->r_objsize = objsize;

#define MAX_CLUSTSIZE   (1<<22)         // 4 MB
#define LINE_ROUND      NM_BUF_ALIGN    // 64
        if (objsize >= MAX_CLUSTSIZE) {
                /* we could do it but there is no point */
                nm_prerr("unsupported allocation for %d bytes", objsize);
                return EINVAL;
        }
        /* make sure objsize is a multiple of LINE_ROUND */
        i = (objsize & (LINE_ROUND - 1));
        if (i) {
                nm_prinf("aligning object by %d bytes", LINE_ROUND - i);
                objsize += LINE_ROUND - i;
        }
        if (objsize < p->objminsize || objsize > p->objmaxsize) {
                nm_prerr("requested objsize %d out of range [%d, %d]",
                        objsize, p->objminsize, p->objmaxsize);
                return EINVAL;
        }
        if (objtotal < p->nummin || objtotal > p->nummax) {
                nm_prerr("requested objtotal %d out of range [%d, %d]",
                        objtotal, p->nummin, p->nummax);
                return EINVAL;
        }
        /*
         * Compute number of objects using a brute-force approach:
         * given a max cluster size,
         * we try to fill it with objects keeping track of the
         * wasted space to the next page boundary.
         */
        for (clustentries = 0, i = 1;; i++) {
                u_int delta, used = i * objsize;
                if (used > MAX_CLUSTSIZE)
                        break;
                delta = used % PAGE_SIZE;
                if (delta == 0) { // exact solution
                        clustentries = i;
                        break;
                }
        }
        /* exact solution not found */
        if (clustentries == 0) {
                nm_prerr("unsupported allocation for %d bytes", objsize);
                return EINVAL;
        }
        /* compute clustsize */
        clustsize = clustentries * objsize;
        if (netmap_debug & NM_DEBUG_MEM)
                nm_prinf("objsize %d clustsize %d objects %d",
                        objsize, clustsize, clustentries);

        /*
         * The number of clusters is n = ceil(objtotal/clustentries)
         * objtotal' = n * clustentries
         */
        p->_clustentries = clustentries;
        p->_clustsize = clustsize;
        p->_numclusters = (objtotal + clustentries - 1) / clustentries;

        /* actual values (may be larger than requested) */
        p->_objsize = objsize;
        p->_objtotal = p->_numclusters * clustentries;

        return 0;
}

/* call with NMA_LOCK held */
static int
netmap_finalize_obj_allocator(struct netmap_mem_d *nmd, struct netmap_obj_pool *p)
{
        int i; /* must be signed */

        if (p->lut) {
                /* if the lut is already there we assume that also all the
                 * clusters have already been allocated, possibly by somebody
                 * else (e.g., extmem). In the latter case, the alloc_done flag
                 * will remain at zero, so that we will not attempt to
                 * deallocate the clusters by ourselves in
                 * netmap_reset_obj_allocator.
                 */
                return 0;
        }

        /* optimistically assume we have enough memory */
        p->numclusters = p->_numclusters;
        p->objtotal = p->_objtotal;
        p->alloc_done = 1;

        p->lut = nm_alloc_lut(p->objtotal);
        if (p->lut == NULL) {
                nm_prerr("Unable to create lookup table for '%s'", p->name);
                goto clean;
        }

        /*
         * Allocate clusters, init pointers
         */

        for (i = 0; i < (int)p->objtotal;) {
                int lim = i + p->_clustentries;
                char *clust;

                /*
                 * XXX Note, we only need contigmalloc() for buffers attached
                 * to native interfaces. In all other cases (nifp, netmap rings
                 * and even buffers for VALE ports or emulated interfaces) we
                 * can live with standard malloc, because the hardware will not
                 * access the pages directly.
                 */
                if (nmd->nm_numa_domain == -1) {
                        clust = contigmalloc(p->_clustsize, M_NETMAP,
                            M_NOWAIT | M_ZERO, (size_t)0, -1UL, PAGE_SIZE, 0);
                } else {
                        struct domainset *ds;

                        ds = DOMAINSET_PREF(nmd->nm_numa_domain);
                        clust = contigmalloc_domainset(p->_clustsize, M_NETMAP,
                            ds, M_NOWAIT | M_ZERO, (size_t)0, -1UL, PAGE_SIZE, 0);
                }
                if (clust == NULL) {
                        /*
                         * If we get here, there is a severe memory shortage,
                         * so halve the allocated memory to reclaim some.
                         */
                        nm_prerr("Unable to create cluster at %d for '%s' allocator",
                            i, p->name);
                        if (i < 2) /* nothing to halve */
                                goto out;
                        lim = i / 2;
                        for (i--; i >= lim; i--) {
                                if (i % p->_clustentries == 0 && p->lut[i].vaddr)
                                        free(p->lut[i].vaddr, M_NETMAP);
                                p->lut[i].vaddr = NULL;
                        }
                out:
                        p->objtotal = i;
                        /* we may have stopped in the middle of a cluster */
                        p->numclusters = (i + p->_clustentries - 1) / p->_clustentries;
                        break;
                }
                /*
                 * Set lut state for all buffers in the current cluster.
                 *
                 * [i, lim) is the set of buffer indexes that cover the
                 * current cluster.
                 *
                 * 'clust' is really the address of the current buffer in
                 * the current cluster as we index through it with a stride
                 * of p->_objsize.
                 */
                for (; i < lim; i++, clust += p->_objsize) {
                        p->lut[i].vaddr = clust;
#if !defined(linux) && !defined(_WIN32)
                        p->lut[i].paddr = vtophys(clust);
#endif
                }
        }
        p->memtotal = (size_t)p->numclusters * (size_t)p->_clustsize;
        if (netmap_verbose)
                nm_prinf("Pre-allocated %d clusters (%d/%zuKB) for '%s'",
                    p->numclusters, p->_clustsize >> 10,
                    p->memtotal >> 10, p->name);

        return 0;

clean:
        netmap_reset_obj_allocator(p);
        return ENOMEM;
}

/* call with lock held */
static int
netmap_mem_params_changed(struct netmap_obj_params* p)
{
        int i, rv = 0;

        for (i = 0; i < NETMAP_POOLS_NR; i++) {
                if (p[i].last_size != p[i].size || p[i].last_num != p[i].num) {
                        p[i].last_size = p[i].size;
                        p[i].last_num = p[i].num;
                        rv = 1;
                }
        }
        return rv;
}

static void
netmap_mem_reset_all(struct netmap_mem_d *nmd)
{
        int i;

        if (netmap_debug & NM_DEBUG_MEM)
                nm_prinf("resetting %p", nmd);
        for (i = 0; i < NETMAP_POOLS_NR; i++) {
                netmap_reset_obj_allocator(&nmd->pools[i]);
        }
        nmd->flags  &= ~NETMAP_MEM_FINALIZED;
}

static int
netmap_mem_unmap(struct netmap_obj_pool *p, struct netmap_adapter *na)
{
        int i, lim = p->objtotal;
        struct netmap_lut *lut;
        if (na == NULL || na->pdev == NULL)
                return 0;

        lut = &na->na_lut;



#if defined(__FreeBSD__)
        /* On FreeBSD mapping and unmapping is performed by the txsync
         * and rxsync routine, packet by packet. */
        (void)i;
        (void)lim;
        (void)lut;
#elif defined(_WIN32)
        (void)i;
        (void)lim;
        (void)lut;
        nm_prerr("unsupported on Windows");
#else /* linux */
        nm_prdis("unmapping and freeing plut for %s", na->name);
        if (lut->plut == NULL || na->pdev == NULL)
                return 0;
        for (i = 0; i < lim; i += p->_clustentries) {
                if (lut->plut[i].paddr)
                        netmap_unload_map(na, (bus_dma_tag_t) na->pdev, &lut->plut[i].paddr, p->_clustsize);
        }
        nm_free_plut(lut->plut);
        lut->plut = NULL;
#endif /* linux */

        return 0;
}

static int
netmap_mem_map(struct netmap_obj_pool *p, struct netmap_adapter *na)
{
        int error = 0;
        int i, lim = p->objtotal;
        struct netmap_lut *lut = &na->na_lut;

        if (na->pdev == NULL)
                return 0;

#if defined(__FreeBSD__)
        /* On FreeBSD mapping and unmapping is performed by the txsync
         * and rxsync routine, packet by packet. */
        (void)i;
        (void)lim;
        (void)lut;
#elif defined(_WIN32)
        (void)i;
        (void)lim;
        (void)lut;
        nm_prerr("unsupported on Windows");
#else /* linux */

        if (lut->plut != NULL) {
                nm_prdis("plut already allocated for %s", na->name);
                return 0;
        }

        nm_prdis("allocating physical lut for %s", na->name);
        lut->plut = nm_alloc_plut(lim);
        if (lut->plut == NULL) {
                nm_prerr("Failed to allocate physical lut for %s", na->name);
                return ENOMEM;
        }

        for (i = 0; i < lim; i += p->_clustentries) {
                lut->plut[i].paddr = 0;
        }

        for (i = 0; i < lim; i += p->_clustentries) {
                int j;

                if (p->lut[i].vaddr == NULL)
                        continue;

                error = netmap_load_map(na, (bus_dma_tag_t) na->pdev, &lut->plut[i].paddr,
                                p->lut[i].vaddr, p->_clustsize);
                if (error) {
                        nm_prerr("Failed to map cluster #%d from the %s pool", i, p->name);
                        break;
                }

                for (j = 1; j < p->_clustentries; j++) {
                        lut->plut[i + j].paddr = lut->plut[i + j - 1].paddr + p->_objsize;
                }
        }

        if (error)
                netmap_mem_unmap(p, na);

#endif /* linux */

        return error;
}

static int
netmap_mem_finalize_all(struct netmap_mem_d *nmd)
{
        int i;
        if (nmd->flags & NETMAP_MEM_FINALIZED)
                return 0;
        nmd->lasterr = 0;
        nmd->nm_totalsize = 0;
        for (i = 0; i < NETMAP_POOLS_NR; i++) {
                nmd->lasterr = netmap_finalize_obj_allocator(nmd, &nmd->pools[i]);
                if (nmd->lasterr)
                        goto error;
                nmd->nm_totalsize += nmd->pools[i].memtotal;
        }
        nmd->nm_totalsize = (nmd->nm_totalsize + PAGE_SIZE - 1) & ~(PAGE_SIZE - 1);
        nmd->lasterr = netmap_mem_init_bitmaps(nmd);
        if (nmd->lasterr)
                goto error;

        nmd->flags |= NETMAP_MEM_FINALIZED;

        if (netmap_verbose)
                nm_prinf("interfaces %zd KB, rings %zd KB, buffers %zd MB",
                    nmd->pools[NETMAP_IF_POOL].memtotal >> 10,
                    nmd->pools[NETMAP_RING_POOL].memtotal >> 10,
                    nmd->pools[NETMAP_BUF_POOL].memtotal >> 20);

        if (netmap_verbose)
                nm_prinf("Free buffers: %d", nmd->pools[NETMAP_BUF_POOL].objfree);


        return 0;
error:
        netmap_mem_reset_all(nmd);
        return nmd->lasterr;
}

/*
 * allocator for private memory
 */
static void *
_netmap_mem_private_new(size_t size, struct netmap_obj_params *p, int grp_id,
                const struct netmap_mem_ops *ops, uint64_t memtotal, int *perr)
{
        struct netmap_mem_d *d = NULL;
        int i, err = 0;
        int checksz = 0;

        /* if memtotal is !=0 we check that the request fits the available
         * memory. Moreover, any surprlus memory is assigned to buffers.
         */
        checksz = (memtotal > 0);

        d = nm_os_malloc(size);
        if (d == NULL) {
                err = ENOMEM;
                goto error;
        }

        *d = nm_blueprint;
        d->ops = ops;

        err = nm_mem_assign_id(d, grp_id);
        if (err)
                goto error_free;
        snprintf(d->name, NM_MEM_NAMESZ, "%d", d->nm_id);

        for (i = 0; i < NETMAP_POOLS_NR; i++) {
                snprintf(d->pools[i].name, NETMAP_POOL_MAX_NAMSZ,
                                nm_blueprint.pools[i].name,
                                d->name);
                if (checksz) {
                        uint64_t poolsz = (uint64_t)p[i].num * p[i].size;
                        if (memtotal < poolsz) {
                                nm_prerr("%s: request too large", d->pools[i].name);
                                err = ENOMEM;
                                goto error_rel_id;
                        }
                        memtotal -= poolsz;
                }
                d->params[i].num = p[i].num;
                d->params[i].size = p[i].size;
        }
        if (checksz && memtotal > 0) {
                uint64_t sz = d->params[NETMAP_BUF_POOL].size;
                uint64_t n = (memtotal + sz - 1) / sz;

                if (n) {
                        if (netmap_verbose) {
                                nm_prinf("%s: adding %llu more buffers",
                                    d->pools[NETMAP_BUF_POOL].name,
                                    (unsigned long long)n);
                        }
                        d->params[NETMAP_BUF_POOL].num += n;
                }
        }

        NMA_LOCK_INIT(d);

        err = netmap_mem_config(d);
        if (err)
                goto error_destroy_lock;

        d->flags &= ~NETMAP_MEM_FINALIZED;

        return d;

error_destroy_lock:
        NMA_LOCK_DESTROY(d);
error_rel_id:
        nm_mem_release_id(d);
error_free:
        nm_os_free(d);
error:
        if (perr)
                *perr = err;
        return NULL;
}

struct netmap_mem_d *
netmap_mem_private_new(u_int txr, u_int txd, u_int rxr, u_int rxd,
                u_int extra_bufs, u_int npipes, int *perr)
{
        struct netmap_mem_d *d = NULL;
        struct netmap_obj_params p[NETMAP_POOLS_NR];
        int i;
        u_int v, maxd;
        /* account for the fake host rings */
        txr++;
        rxr++;

        /* copy the min values */
        for (i = 0; i < NETMAP_POOLS_NR; i++) {
                p[i] = netmap_min_priv_params[i];
        }

        /* possibly increase them to fit user request */
        v = sizeof(struct netmap_if) + sizeof(ssize_t) * (txr + rxr);
        if (p[NETMAP_IF_POOL].size < v)
                p[NETMAP_IF_POOL].size = v;
        v = 2 + 4 * npipes;
        if (p[NETMAP_IF_POOL].num < v)
                p[NETMAP_IF_POOL].num = v;
        maxd = (txd > rxd) ? txd : rxd;
        v = sizeof(struct netmap_ring) + sizeof(struct netmap_slot) * maxd;
        if (p[NETMAP_RING_POOL].size < v)
                p[NETMAP_RING_POOL].size = v;
        /* each pipe endpoint needs two tx rings (1 normal + 1 host, fake)
         * and two rx rings (again, 1 normal and 1 fake host)
         */
        v = txr + rxr + 8 * npipes;
        if (p[NETMAP_RING_POOL].num < v)
                p[NETMAP_RING_POOL].num = v;
        /* for each pipe we only need the buffers for the 4 "real" rings.
         * On the other end, the pipe ring dimension may be different from
         * the parent port ring dimension. As a compromise, we allocate twice the
         * space actually needed if the pipe rings were the same size as the parent rings
         */
        v = (4 * npipes + rxr) * rxd + (4 * npipes + txr) * txd + 2 + extra_bufs;
                /* the +2 is for the tx and rx fake buffers (indices 0 and 1) */
        if (p[NETMAP_BUF_POOL].num < v)
                p[NETMAP_BUF_POOL].num = v;

        if (netmap_verbose)
                nm_prinf("req if %d*%d ring %d*%d buf %d*%d",
                        p[NETMAP_IF_POOL].num,
                        p[NETMAP_IF_POOL].size,
                        p[NETMAP_RING_POOL].num,
                        p[NETMAP_RING_POOL].size,
                        p[NETMAP_BUF_POOL].num,
                        p[NETMAP_BUF_POOL].size);

        d = _netmap_mem_private_new(sizeof(*d), p, -1, &netmap_mem_global_ops, 0, perr);

        return d;
}

/* Reference IOMMU and NUMA local allocator - find existing or create new,
 * for non-hw adapters, fall back to global allocator.
 */
struct netmap_mem_d *
netmap_mem_get_allocator(struct netmap_adapter *na)
{
        int i, domain, err, grp_id;
        struct netmap_mem_d *nmd;

        if (na == NULL || na->pdev == NULL)
                return netmap_mem_get(&nm_mem);

        domain = nm_numa_domain(na->pdev);
        grp_id = nm_iommu_group_id(na->pdev);

        NM_MTX_LOCK(nm_mem_list_lock);
        nmd = netmap_last_mem_d;
        do {
                if (!(nmd->flags & NETMAP_MEM_HIDDEN) &&
                    nmd->nm_grp == grp_id && nmd->nm_numa_domain == domain) {
                        nmd->refcount++;
                        NM_DBG_REFC(nmd, __FUNCTION__, __LINE__);
                        NM_MTX_UNLOCK(nm_mem_list_lock);
                        return nmd;
                }
                nmd = nmd->next;
        } while (nmd != netmap_last_mem_d);

        nmd = nm_os_malloc(sizeof(*nmd));
        if (nmd == NULL)
                goto error;

        *nmd = nm_mem_blueprint;

        err = nm_mem_assign_id_locked(nmd, grp_id, domain);
        if (err)
                goto error_free;

        snprintf(nmd->name, sizeof(nmd->name), "%d", nmd->nm_id);

        for (i = 0; i < NETMAP_POOLS_NR; i++) {
                snprintf(nmd->pools[i].name, NETMAP_POOL_MAX_NAMSZ, "%s-%s",
                        nm_mem_blueprint.pools[i].name, nmd->name);
        }

        NMA_LOCK_INIT(nmd);

        NM_MTX_UNLOCK(nm_mem_list_lock);
        return nmd;

error_free:
        nm_os_free(nmd);
error:
        NM_MTX_UNLOCK(nm_mem_list_lock);
        return NULL;
}

/* call with lock held */
static int
netmap_mem2_config(struct netmap_mem_d *nmd)
{
        int i;

        if (!netmap_mem_params_changed(nmd->params))
                goto out;

        nm_prdis("reconfiguring");

        if (nmd->flags & NETMAP_MEM_FINALIZED) {
                /* reset previous allocation */
                for (i = 0; i < NETMAP_POOLS_NR; i++) {
                        netmap_reset_obj_allocator(&nmd->pools[i]);
                }
                nmd->flags &= ~NETMAP_MEM_FINALIZED;
        }

        for (i = 0; i < NETMAP_POOLS_NR; i++) {
                nmd->lasterr = netmap_config_obj_allocator(&nmd->pools[i],
                                nmd->params[i].num, nmd->params[i].size);
                if (nmd->lasterr)
                        goto out;
        }

out:

        return nmd->lasterr;
}

static int
netmap_mem2_finalize(struct netmap_mem_d *nmd, struct netmap_adapter *na)
{
        if (nmd->flags & NETMAP_MEM_FINALIZED)
                goto out;

        if (netmap_mem_finalize_all(nmd))
                goto out;

        nmd->lasterr = 0;

out:
        return nmd->lasterr;
}

static void
netmap_mem2_delete(struct netmap_mem_d *nmd)
{
        int i;

        for (i = 0; i < NETMAP_POOLS_NR; i++) {
            netmap_destroy_obj_allocator(&nmd->pools[i]);
        }

        NMA_LOCK_DESTROY(nmd);
        if (nmd != &nm_mem)
                nm_os_free(nmd);
}

#ifdef WITH_EXTMEM
/* doubly linekd list of all existing external allocators */
static struct netmap_mem_ext *netmap_mem_ext_list = NULL;
NM_MTX_T nm_mem_ext_list_lock;
#endif /* WITH_EXTMEM */

int
netmap_mem_init(void)
{
        nm_mem_blueprint = nm_mem;
        NM_MTX_INIT(nm_mem_list_lock);
        NMA_LOCK_INIT(&nm_mem);
        netmap_mem_get(&nm_mem);
#ifdef WITH_EXTMEM
        NM_MTX_INIT(nm_mem_ext_list_lock);
#endif /* WITH_EXTMEM */
        return (0);
}

void
netmap_mem_fini(void)
{
        netmap_mem_put(&nm_mem);
}

static int
netmap_mem_ring_needed(struct netmap_kring *kring)
{
        return kring->ring == NULL &&
                (kring->users > 0 ||
                 (kring->nr_kflags & NKR_NEEDRING));
}

static int
netmap_mem_ring_todelete(struct netmap_kring *kring)
{
        return kring->ring != NULL &&
                kring->users == 0 &&
                !(kring->nr_kflags & NKR_NEEDRING);
}


/* call with NMA_LOCK held *
 *
 * Allocate netmap rings and buffers for this card
 * The rings are contiguous, but have variable size.
 * The kring array must follow the layout described
 * in netmap_krings_create().
 */
static int
netmap_mem2_rings_create(struct netmap_mem_d *nmd, struct netmap_adapter *na)
{
        enum txrx t;

        for_rx_tx(t) {
                u_int i;

                for (i = 0; i < netmap_all_rings(na, t); i++) {
                        struct netmap_kring *kring = NMR(na, t)[i];
                        struct netmap_ring *ring = kring->ring;
                        u_int len, ndesc;

                        if (!netmap_mem_ring_needed(kring)) {
                                /* unneeded, or already created by somebody else */
                                if (netmap_debug & NM_DEBUG_MEM)
                                        nm_prinf("NOT creating ring %s (ring %p, users %d neekring %d)",
                                                kring->name, ring, kring->users, kring->nr_kflags & NKR_NEEDRING);
                                continue;
                        }
                        if (netmap_debug & NM_DEBUG_MEM)
                                nm_prinf("creating %s", kring->name);
                        ndesc = kring->nkr_num_slots;
                        len = sizeof(struct netmap_ring) +
                                  ndesc * sizeof(struct netmap_slot);
                        ring = netmap_ring_malloc(nmd, len);
                        if (ring == NULL) {
                                nm_prerr("Cannot allocate %s_ring", nm_txrx2str(t));
                                goto cleanup;
                        }
                        nm_prdis("txring at %p", ring);
                        kring->ring = ring;
                        *(uint32_t *)(uintptr_t)&ring->num_slots = ndesc;
                        *(int64_t *)(uintptr_t)&ring->buf_ofs =
                            (nmd->pools[NETMAP_IF_POOL].memtotal +
                                nmd->pools[NETMAP_RING_POOL].memtotal) -
                                netmap_ring_offset(nmd, ring);

                        /* copy values from kring */
                        ring->head = kring->rhead;
                        ring->cur = kring->rcur;
                        ring->tail = kring->rtail;
                        *(uint32_t *)(uintptr_t)&ring->nr_buf_size =
                                netmap_mem_bufsize(nmd);
                        nm_prdis("%s h %d c %d t %d", kring->name,
                                ring->head, ring->cur, ring->tail);
                        nm_prdis("initializing slots for %s_ring", nm_txrx2str(t));
                        if (!(kring->nr_kflags & NKR_FAKERING)) {
                                /* this is a real ring */
                                if (netmap_debug & NM_DEBUG_MEM)
                                        nm_prinf("allocating buffers for %s", kring->name);
                                if (netmap_new_bufs(nmd, ring->slot, ndesc)) {
                                        nm_prerr("Cannot allocate buffers for %s_ring", nm_txrx2str(t));
                                        goto cleanup;
                                }
                        } else {
                                /* this is a fake ring, set all indices to 0 */
                                if (netmap_debug & NM_DEBUG_MEM)
                                        nm_prinf("NOT allocating buffers for %s", kring->name);
                                netmap_mem_set_ring(nmd, ring->slot, ndesc, 0);
                        }
                        /* ring info */
                        *(uint16_t *)(uintptr_t)&ring->ringid = kring->ring_id;
                        *(uint16_t *)(uintptr_t)&ring->dir = kring->tx;
                }
        }

        return 0;

cleanup:
        /* we cannot actually cleanup here, since we don't own kring->users
         * and kring->nr_klags & NKR_NEEDRING. The caller must decrement
         * the first or zero-out the second, then call netmap_free_rings()
         * to do the cleanup
         */

        return ENOMEM;
}

static void
netmap_mem2_rings_delete(struct netmap_mem_d *nmd, struct netmap_adapter *na)
{
        enum txrx t;

        for_rx_tx(t) {
                u_int i;
                for (i = 0; i < netmap_all_rings(na, t); i++) {
                        struct netmap_kring *kring = NMR(na, t)[i];
                        struct netmap_ring *ring = kring->ring;

                        if (!netmap_mem_ring_todelete(kring)) {
                                if (netmap_debug & NM_DEBUG_MEM)
                                        nm_prinf("NOT deleting ring %s (ring %p, users %d neekring %d)",
                                                kring->name, ring, kring->users, kring->nr_kflags & NKR_NEEDRING);
                                continue;
                        }
                        if (netmap_debug & NM_DEBUG_MEM)
                                nm_prinf("deleting ring %s", kring->name);
                        if (!(kring->nr_kflags & NKR_FAKERING)) {
                                nm_prdis("freeing bufs for %s", kring->name);
                                netmap_free_bufs(nmd, ring->slot, kring->nkr_num_slots);
                        } else {
                                nm_prdis("NOT freeing bufs for %s", kring->name);
                        }
                        netmap_ring_free(nmd, ring);
                        kring->ring = NULL;
                }
        }
}

/* call with NMA_LOCK held */
/*
 * Allocate the per-fd structure netmap_if.
 *
 * We assume that the configuration stored in na
 * (number of tx/rx rings and descs) does not change while
 * the interface is in netmap mode.
 */
static struct netmap_if *
netmap_mem2_if_new(struct netmap_mem_d *nmd,
                struct netmap_adapter *na, struct netmap_priv_d *priv)
{
        struct netmap_if *nifp;
        ssize_t base; /* handy for relative offsets between rings and nifp */
        u_int i, len, n[NR_TXRX], ntot;
        enum txrx t;

        ntot = 0;
        for_rx_tx(t) {
                /* account for the (eventually fake) host rings */
                n[t] = netmap_all_rings(na, t);
                ntot += n[t];
        }
        /*
         * the descriptor is followed inline by an array of offsets
         * to the tx and rx rings in the shared memory region.
         */

        len = sizeof(struct netmap_if) + (ntot * sizeof(ssize_t));
        nifp = netmap_if_malloc(nmd, len);
        if (nifp == NULL) {
                return NULL;
        }

        /* initialize base fields -- override const */
        *(u_int *)(uintptr_t)&nifp->ni_tx_rings = na->num_tx_rings;
        *(u_int *)(uintptr_t)&nifp->ni_rx_rings = na->num_rx_rings;
        *(u_int *)(uintptr_t)&nifp->ni_host_tx_rings =
                (na->num_host_tx_rings ? na->num_host_tx_rings : 1);
        *(u_int *)(uintptr_t)&nifp->ni_host_rx_rings =
                (na->num_host_rx_rings ? na->num_host_rx_rings : 1);
        strlcpy(nifp->ni_name, na->name, sizeof(nifp->ni_name));

        /*
         * fill the slots for the rx and tx rings. They contain the offset
         * between the ring and nifp, so the information is usable in
         * userspace to reach the ring from the nifp.
         */
        base = netmap_if_offset(nmd, nifp);
        for (i = 0; i < n[NR_TX]; i++) {
                /* XXX instead of ofs == 0 maybe use the offset of an error
                 * ring, like we do for buffers? */
                ssize_t ofs = 0;

                if (na->tx_rings[i]->ring != NULL && i >= priv->np_qfirst[NR_TX]
                                && i < priv->np_qlast[NR_TX]) {
                        ofs = netmap_ring_offset(nmd,
                                                 na->tx_rings[i]->ring) - base;
                }
                *(ssize_t *)(uintptr_t)&nifp->ring_ofs[i] = ofs;
        }
        for (i = 0; i < n[NR_RX]; i++) {
                /* XXX instead of ofs == 0 maybe use the offset of an error
                 * ring, like we do for buffers? */
                ssize_t ofs = 0;

                if (na->rx_rings[i]->ring != NULL && i >= priv->np_qfirst[NR_RX]
                                && i < priv->np_qlast[NR_RX]) {
                        ofs = netmap_ring_offset(nmd,
                                                 na->rx_rings[i]->ring) - base;
                }
                *(ssize_t *)(uintptr_t)&nifp->ring_ofs[i+n[NR_TX]] = ofs;
        }

        return (nifp);
}

static void
netmap_mem2_if_delete(struct netmap_mem_d *nmd,
                struct netmap_adapter *na, struct netmap_if *nifp)
{
        if (nifp == NULL)
                /* nothing to do */
                return;
        if (nifp->ni_bufs_head)
                netmap_extra_free(na, nifp->ni_bufs_head);
        netmap_if_free(nmd, nifp);
}

static void
netmap_mem2_deref(struct netmap_mem_d *nmd, struct netmap_adapter *na)
{

        if (netmap_debug & NM_DEBUG_MEM)
                nm_prinf("active = %d", nmd->active);

}

const struct netmap_mem_ops netmap_mem_global_ops = {
        .nmd_get_lut = netmap_mem2_get_lut,
        .nmd_get_info = netmap_mem2_get_info,
        .nmd_ofstophys = netmap_mem2_ofstophys,
        .nmd_config = netmap_mem2_config,
        .nmd_finalize = netmap_mem2_finalize,
        .nmd_deref = netmap_mem2_deref,
        .nmd_delete = netmap_mem2_delete,
        .nmd_if_offset = netmap_mem2_if_offset,
        .nmd_if_new = netmap_mem2_if_new,
        .nmd_if_delete = netmap_mem2_if_delete,
        .nmd_rings_create = netmap_mem2_rings_create,
        .nmd_rings_delete = netmap_mem2_rings_delete
};

int
netmap_mem_pools_info_get(struct nmreq_pools_info *req,
                                struct netmap_mem_d *nmd)
{
        int ret;

        ret = netmap_mem_get_info(nmd, &req->nr_memsize, NULL,
                                        &req->nr_mem_id);
        if (ret) {
                return ret;
        }

        NMA_LOCK(nmd);
        req->nr_if_pool_offset = 0;
        req->nr_if_pool_objtotal = nmd->pools[NETMAP_IF_POOL].objtotal;
        req->nr_if_pool_objsize = nmd->pools[NETMAP_IF_POOL]._objsize;

        req->nr_ring_pool_offset = nmd->pools[NETMAP_IF_POOL].memtotal;
        req->nr_ring_pool_objtotal = nmd->pools[NETMAP_RING_POOL].objtotal;
        req->nr_ring_pool_objsize = nmd->pools[NETMAP_RING_POOL]._objsize;

        req->nr_buf_pool_offset = nmd->pools[NETMAP_IF_POOL].memtotal +
                             nmd->pools[NETMAP_RING_POOL].memtotal;
        req->nr_buf_pool_objtotal = nmd->pools[NETMAP_BUF_POOL].objtotal;
        req->nr_buf_pool_objsize = nmd->pools[NETMAP_BUF_POOL]._objsize;
        NMA_UNLOCK(nmd);

        return 0;
}

#ifdef WITH_EXTMEM
struct netmap_mem_ext {
        struct netmap_mem_d up;

        struct nm_os_extmem *os;
        struct netmap_mem_ext *next, *prev;
};

/* call with nm_mem_list_lock held */
static void
netmap_mem_ext_register(struct netmap_mem_ext *e)
{
        NM_MTX_LOCK(nm_mem_ext_list_lock);
        if (netmap_mem_ext_list)
                netmap_mem_ext_list->prev = e;
        e->next = netmap_mem_ext_list;
        netmap_mem_ext_list = e;
        e->prev = NULL;
        NM_MTX_UNLOCK(nm_mem_ext_list_lock);
}

/* call with nm_mem_list_lock held */
static void
netmap_mem_ext_unregister(struct netmap_mem_ext *e)
{
        if (e->prev)
                e->prev->next = e->next;
        else
                netmap_mem_ext_list = e->next;
        if (e->next)
                e->next->prev = e->prev;
        e->prev = e->next = NULL;
}

static struct netmap_mem_ext *
netmap_mem_ext_search(struct nm_os_extmem *os)
{
        struct netmap_mem_ext *e;

        NM_MTX_LOCK(nm_mem_ext_list_lock);
        for (e = netmap_mem_ext_list; e; e = e->next) {
                if (nm_os_extmem_isequal(e->os, os)) {
                        netmap_mem_get(&e->up);
                        break;
                }
        }
        NM_MTX_UNLOCK(nm_mem_ext_list_lock);
        return e;
}


static void
netmap_mem_ext_delete(struct netmap_mem_d *d)
{
        int i;
        struct netmap_mem_ext *e =
                (struct netmap_mem_ext *)d;

        netmap_mem_ext_unregister(e);

        for (i = 0; i < NETMAP_POOLS_NR; i++) {
                struct netmap_obj_pool *p = &d->pools[i];

                if (p->lut) {
                        nm_free_lut(p->lut, p->objtotal);
                        p->lut = NULL;
                }
        }
        if (e->os)
                nm_os_extmem_delete(e->os);
        netmap_mem2_delete(d);
}

static int
netmap_mem_ext_config(struct netmap_mem_d *nmd)
{
        return 0;
}

struct netmap_mem_ops netmap_mem_ext_ops = {
        .nmd_get_lut = netmap_mem2_get_lut,
        .nmd_get_info = netmap_mem2_get_info,
        .nmd_ofstophys = netmap_mem2_ofstophys,
        .nmd_config = netmap_mem_ext_config,
        .nmd_finalize = netmap_mem2_finalize,
        .nmd_deref = netmap_mem2_deref,
        .nmd_delete = netmap_mem_ext_delete,
        .nmd_if_offset = netmap_mem2_if_offset,
        .nmd_if_new = netmap_mem2_if_new,
        .nmd_if_delete = netmap_mem2_if_delete,
        .nmd_rings_create = netmap_mem2_rings_create,
        .nmd_rings_delete = netmap_mem2_rings_delete
};

struct netmap_mem_d *
netmap_mem_ext_create(uint64_t usrptr, struct nmreq_pools_info *pi, int *perror)
{
        int error = 0;
        int i, j;
        struct netmap_mem_ext *nme;
        char *clust;
        size_t off;
        struct nm_os_extmem *os = NULL;
        int nr_pages;

        // XXX sanity checks
        if (pi->nr_if_pool_objtotal == 0)
                pi->nr_if_pool_objtotal = netmap_min_priv_params[NETMAP_IF_POOL].num;
        if (pi->nr_if_pool_objsize == 0)
                pi->nr_if_pool_objsize = netmap_min_priv_params[NETMAP_IF_POOL].size;
        if (pi->nr_ring_pool_objtotal == 0)
                pi->nr_ring_pool_objtotal = netmap_min_priv_params[NETMAP_RING_POOL].num;
        if (pi->nr_ring_pool_objsize == 0)
                pi->nr_ring_pool_objsize = netmap_min_priv_params[NETMAP_RING_POOL].size;
        if (pi->nr_buf_pool_objtotal == 0)
                pi->nr_buf_pool_objtotal = netmap_min_priv_params[NETMAP_BUF_POOL].num;
        if (pi->nr_buf_pool_objsize == 0)
                pi->nr_buf_pool_objsize = netmap_min_priv_params[NETMAP_BUF_POOL].size;
        if (netmap_verbose & NM_DEBUG_MEM)
                nm_prinf("if %d %d ring %d %d buf %d %d",
                        pi->nr_if_pool_objtotal, pi->nr_if_pool_objsize,
                        pi->nr_ring_pool_objtotal, pi->nr_ring_pool_objsize,
                        pi->nr_buf_pool_objtotal, pi->nr_buf_pool_objsize);

        os = nm_os_extmem_create(usrptr, pi, &error);
        if (os == NULL) {
                nm_prerr("os extmem creation failed");
                goto out;
        }

        nme = netmap_mem_ext_search(os);
        if (nme) {
                nm_os_extmem_delete(os);
                return &nme->up;
        }
        if (netmap_verbose & NM_DEBUG_MEM)
                nm_prinf("not found, creating new");

        nme = _netmap_mem_private_new(sizeof(*nme),

                        (struct netmap_obj_params[]){
                                { pi->nr_if_pool_objsize, pi->nr_if_pool_objtotal },
                                { pi->nr_ring_pool_objsize, pi->nr_ring_pool_objtotal },
                                { pi->nr_buf_pool_objsize, pi->nr_buf_pool_objtotal }},
                        -1,
                        &netmap_mem_ext_ops,
                        pi->nr_memsize,
                        &error);
        if (nme == NULL)
                goto out_unmap;

        nr_pages = nm_os_extmem_nr_pages(os);

        /* from now on pages will be released by nme destructor;
         * we let res = 0 to prevent release in out_unmap below
         */
        nme->os = os;
        os = NULL; /* pass ownership */

        clust = nm_os_extmem_nextpage(nme->os);
        off = 0;
        for (i = 0; i < NETMAP_POOLS_NR; i++) {
                struct netmap_obj_pool *p = &nme->up.pools[i];
                struct netmap_obj_params *o = &nme->up.params[i];

                p->_objsize = o->size;
                p->_clustsize = o->size;
                p->_clustentries = 1;

                p->lut = nm_alloc_lut(o->num);
                if (p->lut == NULL) {
                        error = ENOMEM;
                        goto out_delete;
                }

                p->bitmap_slots = (o->num + sizeof(uint32_t) - 1) / sizeof(uint32_t);
                p->invalid_bitmap = nm_os_malloc(sizeof(uint32_t) * p->bitmap_slots);
                if (p->invalid_bitmap == NULL) {
                        error = ENOMEM;
                        goto out_delete;
                }

                if (nr_pages == 0) {
                        p->objtotal = 0;
                        p->memtotal = 0;
                        p->objfree = 0;
                        continue;
                }

                for (j = 0; j < o->num && nr_pages > 0; j++) {
                        size_t noff;

                        p->lut[j].vaddr = clust + off;
#if !defined(linux) && !defined(_WIN32)
                        p->lut[j].paddr = vtophys(p->lut[j].vaddr);
#endif
                        nm_prdis("%s %d at %p", p->name, j, p->lut[j].vaddr);
                        noff = off + p->_objsize;
                        if (noff < PAGE_SIZE) {
                                off = noff;
                                continue;
                        }
                        nm_prdis("too big, recomputing offset...");
                        while (noff >= PAGE_SIZE) {
                                char *old_clust = clust;
                                noff -= PAGE_SIZE;
                                clust = nm_os_extmem_nextpage(nme->os);
                                nr_pages--;
                                nm_prdis("noff %zu page %p nr_pages %d", noff,
                                                page_to_virt(*pages), nr_pages);
                                if (noff > 0 && !nm_isset(p->invalid_bitmap, j) &&
                                        (nr_pages == 0 ||
                                         old_clust + PAGE_SIZE != clust))
                                {
                                        /* out of space or non contiguous,
                                         * drop this object
                                         * */
                                        p->invalid_bitmap[ (j>>5) ] |= 1U << (j & 31U);
                                        nm_prdis("non contiguous at off %zu, drop", noff);
                                }
                                if (nr_pages == 0)
                                        break;
                        }
                        off = noff;
                }
                p->objtotal = j;
                p->numclusters = p->objtotal;
                p->memtotal = j * (size_t)p->_objsize;
                nm_prdis("%d memtotal %zu", j, p->memtotal);
        }

        netmap_mem_ext_register(nme);

        return &nme->up;

out_delete:
        netmap_mem_put(&nme->up);
out_unmap:
        if (os)
                nm_os_extmem_delete(os);
out:
        if (perror)
                *perror = error;
        return NULL;

}
#endif /* WITH_EXTMEM */


#ifdef WITH_PTNETMAP
struct mem_pt_if {
        struct mem_pt_if *next;
        if_t ifp;
        unsigned int nifp_offset;
};

/* Netmap allocator for ptnetmap guests. */
struct netmap_mem_ptg {
        struct netmap_mem_d up;

        vm_paddr_t nm_paddr;            /* physical address in the guest */
        void *nm_addr;                  /* virtual address in the guest */
        struct netmap_lut buf_lut;      /* lookup table for BUF pool in the guest */
        nm_memid_t host_mem_id;         /* allocator identifier in the host */
        struct ptnetmap_memdev *ptn_dev;/* ptnetmap memdev */
        struct mem_pt_if *pt_ifs;       /* list of interfaces in passthrough */
};

/* Link a passthrough interface to a passthrough netmap allocator. */
static int
netmap_mem_pt_guest_ifp_add(struct netmap_mem_d *nmd, if_t ifp,
                            unsigned int nifp_offset)
{
        struct netmap_mem_ptg *ptnmd = (struct netmap_mem_ptg *)nmd;
        struct mem_pt_if *ptif = nm_os_malloc(sizeof(*ptif));

        if (!ptif) {
                return ENOMEM;
        }

        NMA_LOCK(nmd);

        ptif->ifp = ifp;
        ptif->nifp_offset = nifp_offset;

        if (ptnmd->pt_ifs) {
                ptif->next = ptnmd->pt_ifs;
        }
        ptnmd->pt_ifs = ptif;

        NMA_UNLOCK(nmd);

        nm_prinf("ifp=%s,nifp_offset=%u",
                if_name(ptif->ifp), ptif->nifp_offset);

        return 0;
}

/* Called with NMA_LOCK(nmd) held. */
static struct mem_pt_if *
netmap_mem_pt_guest_ifp_lookup(struct netmap_mem_d *nmd, if_t ifp)
{
        struct netmap_mem_ptg *ptnmd = (struct netmap_mem_ptg *)nmd;
        struct mem_pt_if *curr;

        for (curr = ptnmd->pt_ifs; curr; curr = curr->next) {
                if (curr->ifp == ifp) {
                        return curr;
                }
        }

        return NULL;
}

/* Unlink a passthrough interface from a passthrough netmap allocator. */
int
netmap_mem_pt_guest_ifp_del(struct netmap_mem_d *nmd, if_t ifp)
{
        struct netmap_mem_ptg *ptnmd = (struct netmap_mem_ptg *)nmd;
        struct mem_pt_if *prev = NULL;
        struct mem_pt_if *curr;
        int ret = -1;

        NMA_LOCK(nmd);

        for (curr = ptnmd->pt_ifs; curr; curr = curr->next) {
                if (curr->ifp == ifp) {
                        if (prev) {
                                prev->next = curr->next;
                        } else {
                                ptnmd->pt_ifs = curr->next;
                        }
                        nm_prinf("removed (ifp=%s,nifp_offset=%u)",
                          if_name(curr->ifp), curr->nifp_offset);
                        nm_os_free(curr);
                        ret = 0;
                        break;
                }
                prev = curr;
        }

        NMA_UNLOCK(nmd);

        return ret;
}

static int
netmap_mem_pt_guest_get_lut(struct netmap_mem_d *nmd, struct netmap_lut *lut)
{
        struct netmap_mem_ptg *ptnmd = (struct netmap_mem_ptg *)nmd;

        if (!(nmd->flags & NETMAP_MEM_FINALIZED)) {
                return EINVAL;
        }

        *lut = ptnmd->buf_lut;
        return 0;
}

static int
netmap_mem_pt_guest_get_info(struct netmap_mem_d *nmd, uint64_t *size,
                             u_int *memflags, uint16_t *id)
{
        int error = 0;

        error = nmd->ops->nmd_config(nmd);
        if (error)
                goto out;

        if (size)
                *size = nmd->nm_totalsize;
        if (memflags)
                *memflags = nmd->flags;
        if (id)
                *id = nmd->nm_id;

out:

        return error;
}

static vm_paddr_t
netmap_mem_pt_guest_ofstophys(struct netmap_mem_d *nmd, vm_ooffset_t off)
{
        struct netmap_mem_ptg *ptnmd = (struct netmap_mem_ptg *)nmd;
        vm_paddr_t paddr;
        /* if the offset is valid, just return csb->base_addr + off */
        paddr = (vm_paddr_t)(ptnmd->nm_paddr + off);
        nm_prdis("off %lx padr %lx", off, (unsigned long)paddr);
        return paddr;
}

static int
netmap_mem_pt_guest_config(struct netmap_mem_d *nmd)
{
        /* nothing to do, we are configured on creation
         * and configuration never changes thereafter
         */
        return 0;
}

static int
netmap_mem_pt_guest_finalize(struct netmap_mem_d *nmd, struct netmap_adapter *na)
{
        struct netmap_mem_ptg *ptnmd = (struct netmap_mem_ptg *)nmd;
        uint64_t mem_size;
        uint32_t bufsize;
        uint32_t nbuffers;
        uint32_t poolofs;
        vm_paddr_t paddr;
        char *vaddr;
        int i;
        int error = 0;

        if (nmd->flags & NETMAP_MEM_FINALIZED)
                goto out;

        if (ptnmd->ptn_dev == NULL) {
                nm_prerr("ptnetmap memdev not attached");
                error = ENOMEM;
                goto out;
        }
        /* Map memory through ptnetmap-memdev BAR. */
        error = nm_os_pt_memdev_iomap(ptnmd->ptn_dev, &ptnmd->nm_paddr,
                                      &ptnmd->nm_addr, &mem_size);
        if (error)
                goto out;

        /* Initialize the lut using the information contained in the
         * ptnetmap memory device. */
        bufsize = nm_os_pt_memdev_ioread(ptnmd->ptn_dev,
                                         PTNET_MDEV_IO_BUF_POOL_OBJSZ);
        nbuffers = nm_os_pt_memdev_ioread(ptnmd->ptn_dev,
                                         PTNET_MDEV_IO_BUF_POOL_OBJNUM);

        /* allocate the lut */
        if (ptnmd->buf_lut.lut == NULL) {
                nm_prinf("allocating lut");
                ptnmd->buf_lut.lut = nm_alloc_lut(nbuffers);
                if (ptnmd->buf_lut.lut == NULL) {
                        nm_prerr("lut allocation failed");
                        return ENOMEM;
                }
        }

        /* we have physically contiguous memory mapped through PCI BAR */
        poolofs = nm_os_pt_memdev_ioread(ptnmd->ptn_dev,
                                         PTNET_MDEV_IO_BUF_POOL_OFS);
        vaddr = (char *)(ptnmd->nm_addr) + poolofs;
        paddr = ptnmd->nm_paddr + poolofs;

        for (i = 0; i < nbuffers; i++) {
                ptnmd->buf_lut.lut[i].vaddr = vaddr;
                vaddr += bufsize;
                paddr += bufsize;
        }

        ptnmd->buf_lut.objtotal = nbuffers;
        ptnmd->buf_lut.objsize = bufsize;
        nmd->nm_totalsize = mem_size;

        /* Initialize these fields as are needed by
         * netmap_mem_bufsize().
         * XXX please improve this, why do we need this
         * replication? maybe we nmd->pools[] should no be
         * there for the guest allocator? */
        nmd->pools[NETMAP_BUF_POOL]._objsize = bufsize;
        nmd->pools[NETMAP_BUF_POOL]._objtotal = nbuffers;

        nmd->flags |= NETMAP_MEM_FINALIZED;
out:
        return error;
}

static void
netmap_mem_pt_guest_deref(struct netmap_mem_d *nmd, struct netmap_adapter *na)
{
        struct netmap_mem_ptg *ptnmd = (struct netmap_mem_ptg *)nmd;

        if (nmd->active == 1 &&
                (nmd->flags & NETMAP_MEM_FINALIZED)) {
            nmd->flags  &= ~NETMAP_MEM_FINALIZED;
            /* unmap ptnetmap-memdev memory */
            if (ptnmd->ptn_dev) {
                nm_os_pt_memdev_iounmap(ptnmd->ptn_dev);
            }
            ptnmd->nm_addr = NULL;
            ptnmd->nm_paddr = 0;
        }
}

static ssize_t
netmap_mem_pt_guest_if_offset(struct netmap_mem_d *nmd, const void *vaddr)
{
        struct netmap_mem_ptg *ptnmd = (struct netmap_mem_ptg *)nmd;

        return (const char *)(vaddr) - (char *)(ptnmd->nm_addr);
}

static void
netmap_mem_pt_guest_delete(struct netmap_mem_d *nmd)
{
        if (nmd == NULL)
                return;
        if (netmap_verbose)
                nm_prinf("deleting %p", nmd);
        if (nmd->active > 0)
                nm_prerr("bug: deleting mem allocator with active=%d!", nmd->active);
        if (netmap_verbose)
                nm_prinf("done deleting %p", nmd);
        NMA_LOCK_DESTROY(nmd);
        nm_os_free(nmd);
}

static struct netmap_if *
netmap_mem_pt_guest_if_new(struct netmap_mem_d *nmd,
                struct netmap_adapter *na, struct netmap_priv_d *priv)
{
        struct netmap_mem_ptg *ptnmd = (struct netmap_mem_ptg *)nmd;
        struct mem_pt_if *ptif;
        struct netmap_if *nifp = NULL;

        ptif = netmap_mem_pt_guest_ifp_lookup(nmd, na->ifp);
        if (ptif == NULL) {
                nm_prerr("interface %s is not in passthrough", na->name);
                goto out;
        }

        nifp = (struct netmap_if *)((char *)(ptnmd->nm_addr) +
                                    ptif->nifp_offset);
out:
        return nifp;
}

static void
netmap_mem_pt_guest_if_delete(struct netmap_mem_d * nmd,
                struct netmap_adapter *na, struct netmap_if *nifp)
{
        struct mem_pt_if *ptif;

        ptif = netmap_mem_pt_guest_ifp_lookup(nmd, na->ifp);
        if (ptif == NULL) {
                nm_prerr("interface %s is not in passthrough", na->name);
        }
}

static int
netmap_mem_pt_guest_rings_create(struct netmap_mem_d *nmd,
                struct netmap_adapter *na)
{
        struct netmap_mem_ptg *ptnmd = (struct netmap_mem_ptg *)nmd;
        struct mem_pt_if *ptif;
        struct netmap_if *nifp;
        int i, error = -1;

        ptif = netmap_mem_pt_guest_ifp_lookup(nmd, na->ifp);
        if (ptif == NULL) {
                nm_prerr("interface %s is not in passthrough", na->name);
                goto out;
        }


        /* point each kring to the corresponding backend ring */
        nifp = (struct netmap_if *)((char *)ptnmd->nm_addr + ptif->nifp_offset);
        for (i = 0; i < netmap_all_rings(na, NR_TX); i++) {
                struct netmap_kring *kring = na->tx_rings[i];
                if (kring->ring)
                        continue;
                kring->ring = (struct netmap_ring *)
                        ((char *)nifp + nifp->ring_ofs[i]);
        }
        for (i = 0; i < netmap_all_rings(na, NR_RX); i++) {
                struct netmap_kring *kring = na->rx_rings[i];
                if (kring->ring)
                        continue;
                kring->ring = (struct netmap_ring *)
                        ((char *)nifp +
                         nifp->ring_ofs[netmap_all_rings(na, NR_TX) + i]);
        }

        error = 0;
out:
        return error;
}

static void
netmap_mem_pt_guest_rings_delete(struct netmap_mem_d *nmd, struct netmap_adapter *na)
{
#if 0
        enum txrx t;

        for_rx_tx(t) {
                u_int i;
                for (i = 0; i < nma_get_nrings(na, t) + 1; i++) {
                        struct netmap_kring *kring = &NMR(na, t)[i];

                        kring->ring = NULL;
                }
        }
#endif
        (void)nmd;
        (void)na;
}

static struct netmap_mem_ops netmap_mem_pt_guest_ops = {
        .nmd_get_lut = netmap_mem_pt_guest_get_lut,
        .nmd_get_info = netmap_mem_pt_guest_get_info,
        .nmd_ofstophys = netmap_mem_pt_guest_ofstophys,
        .nmd_config = netmap_mem_pt_guest_config,
        .nmd_finalize = netmap_mem_pt_guest_finalize,
        .nmd_deref = netmap_mem_pt_guest_deref,
        .nmd_if_offset = netmap_mem_pt_guest_if_offset,
        .nmd_delete = netmap_mem_pt_guest_delete,
        .nmd_if_new = netmap_mem_pt_guest_if_new,
        .nmd_if_delete = netmap_mem_pt_guest_if_delete,
        .nmd_rings_create = netmap_mem_pt_guest_rings_create,
        .nmd_rings_delete = netmap_mem_pt_guest_rings_delete
};

/* Called with nm_mem_list_lock held. */
static struct netmap_mem_d *
netmap_mem_pt_guest_find_memid(nm_memid_t mem_id)
{
        struct netmap_mem_d *mem = NULL;
        struct netmap_mem_d *scan = netmap_last_mem_d;

        do {
                /* find ptnetmap allocator through host ID */
                if (scan->ops->nmd_deref == netmap_mem_pt_guest_deref &&
                        ((struct netmap_mem_ptg *)(scan))->host_mem_id == mem_id) {
                        mem = scan;
                        mem->refcount++;
                        NM_DBG_REFC(mem, __FUNCTION__, __LINE__);
                        break;
                }
                scan = scan->next;
        } while (scan != netmap_last_mem_d);

        return mem;
}

/* Called with nm_mem_list_lock held. */
static struct netmap_mem_d *
netmap_mem_pt_guest_create(nm_memid_t mem_id)
{
        struct netmap_mem_ptg *ptnmd;
        int err = 0;

        ptnmd = nm_os_malloc(sizeof(struct netmap_mem_ptg));
        if (ptnmd == NULL) {
                err = ENOMEM;
                goto error;
        }

        ptnmd->up.ops = &netmap_mem_pt_guest_ops;
        ptnmd->host_mem_id = mem_id;
        ptnmd->pt_ifs = NULL;

        /* Assign new id in the guest (We have the lock) */
        err = nm_mem_assign_id_locked(&ptnmd->up, -1, -1);
        if (err)
                goto error;

        ptnmd->up.flags &= ~NETMAP_MEM_FINALIZED;
        ptnmd->up.flags |= NETMAP_MEM_IO;

        NMA_LOCK_INIT(&ptnmd->up);

        snprintf(ptnmd->up.name, NM_MEM_NAMESZ, "%d", ptnmd->up.nm_id);


        return &ptnmd->up;
error:
        netmap_mem_pt_guest_delete(&ptnmd->up);
        return NULL;
}

/*
 * find host id in guest allocators and create guest allocator
 * if it is not there
 */
static struct netmap_mem_d *
netmap_mem_pt_guest_get(nm_memid_t mem_id)
{
        struct netmap_mem_d *nmd;

        NM_MTX_LOCK(nm_mem_list_lock);
        nmd = netmap_mem_pt_guest_find_memid(mem_id);
        if (nmd == NULL) {
                nmd = netmap_mem_pt_guest_create(mem_id);
        }
        NM_MTX_UNLOCK(nm_mem_list_lock);

        return nmd;
}

/*
 * The guest allocator can be created by ptnetmap_memdev (during the device
 * attach) or by ptnetmap device (ptnet), during the netmap_attach.
 *
 * The order is not important (we have different order in LINUX and FreeBSD).
 * The first one, creates the device, and the second one simply attaches it.
 */

/* Called when ptnetmap_memdev is attaching, to attach a new allocator in
 * the guest */
struct netmap_mem_d *
netmap_mem_pt_guest_attach(struct ptnetmap_memdev *ptn_dev, nm_memid_t mem_id)
{
        struct netmap_mem_d *nmd;
        struct netmap_mem_ptg *ptnmd;

        nmd = netmap_mem_pt_guest_get(mem_id);

        /* assign this device to the guest allocator */
        if (nmd) {
                ptnmd = (struct netmap_mem_ptg *)nmd;
                ptnmd->ptn_dev = ptn_dev;
        }

        return nmd;
}

/* Called when ptnet device is attaching */
struct netmap_mem_d *
netmap_mem_pt_guest_new(if_t ifp,
                        unsigned int nifp_offset,
                        unsigned int memid)
{
        struct netmap_mem_d *nmd;

        if (ifp == NULL) {
                return NULL;
        }

        nmd = netmap_mem_pt_guest_get((nm_memid_t)memid);

        if (nmd) {
                netmap_mem_pt_guest_ifp_add(nmd, ifp, nifp_offset);
        }

        return nmd;
}

#endif /* WITH_PTNETMAP */