/*
  Copyright (c) 2012-2014 DataLab, s.l. <http://www.datalab.es>
  This file is part of GlusterFS.

  This file is licensed to you under your choice of the GNU Lesser
  General Public License, version 3 or any later version (LGPLv3 or
  later), or the GNU General Public License, version 2 (GPLv2), in all
  cases as published by the Free Software Foundation.
*/

#include <libgen.h>

#include <glusterfs/byte-order.h>

#include "ec.h"
#include "ec-mem-types.h"
#include "ec-messages.h"
#include "ec-fops.h"
#include "ec-method.h"
#include "ec-helpers.h"

static const char *ec_fop_list[] = {[-EC_FOP_HEAL] = "HEAL"};

const char *
ec_bin(char *str, size_t size, uint64_t value, int32_t digits)
{
    str += size;

    if (size-- < 1) {
        goto failed;
    }
    *--str = 0;

    while ((value != 0) || (digits > 0)) {
        if (size-- < 1) {
            goto failed;
        }
        *--str = '0' + (value & 1);
        digits--;
        value >>= 1;
    }

    return str;

failed:
    return "<buffer too small>";
}

const char *
ec_fop_name(int32_t id)
{
    if (id >= 0) {
        return gf_fop_list[id];
    }

    return ec_fop_list[-id];
}

void
ec_trace(const char *event, ec_fop_data_t *fop, const char *fmt, ...)
{
    char str1[32], str2[32], str3[32];
    char *msg;
    ec_t *ec = fop->xl->private;
    va_list args;
    int32_t ret;

    va_start(args, fmt);
    ret = vasprintf(&msg, fmt, args);
    va_end(args);

    if (ret < 0) {
        msg = "<memory allocation error>";
    }

    gf_msg_trace("ec", 0,
                 "%s(%s) %p(%p) [refs=%d, winds=%d, jobs=%d] "
                 "frame=%p/%p, min/exp=%d/%d, err=%d state=%d "
                 "{%s:%s:%s} %s",
                 event, ec_fop_name(fop->id), fop, fop->parent, fop->refs,
                 fop->winds, fop->jobs, fop->req_frame, fop->frame,
                 fop->minimum, fop->expected, fop->error, fop->state,
                 ec_bin(str1, sizeof(str1), fop->mask, ec->nodes),
                 ec_bin(str2, sizeof(str2), fop->remaining, ec->nodes),
                 ec_bin(str3, sizeof(str3), fop->good, ec->nodes), msg);

    if (ret >= 0) {
        free(msg);
    }
}

int32_t
ec_bits_consume(uint64_t *n)
{
    uint64_t tmp;

    tmp = *n;
    tmp &= -tmp;
    *n ^= tmp;

    return gf_bits_index(tmp);
}

size_t
ec_iov_copy_to(void *dst, struct iovec *vector, int32_t count, off_t offset,
               size_t size)
{
    int32_t i = 0;
    size_t total = 0, len = 0;

    while (i < count) {
        if (offset < vector[i].iov_len) {
            while ((i < count) && (size > 0)) {
                len = size;
                if (len > vector[i].iov_len - offset) {
                    len = vector[i].iov_len - offset;
                }
                memcpy(dst, vector[i++].iov_base + offset, len);
                offset = 0;
                dst += len;
                total += len;
                size -= len;
            }

            break;
        }

        offset -= vector[i].iov_len;
        i++;
    }

    return total;
}

int32_t
ec_buffer_alloc(xlator_t *xl, size_t size, struct iobref **piobref, void **ptr)
{
    struct iobref *iobref = NULL;
    struct iobuf *iobuf = NULL;
    int32_t ret = -ENOMEM;

    iobuf = iobuf_get_page_aligned(xl->ctx->iobuf_pool, size,
                                   EC_METHOD_WORD_SIZE);
    if (iobuf == NULL) {
        goto out;
    }

    iobref = *piobref;
    if (iobref == NULL) {
        iobref = iobref_new();
        if (iobref == NULL) {
            goto out;
        }
    }

    ret = iobref_add(iobref, iobuf);
    if (ret != 0) {
        if (iobref != *piobref) {
            iobref_unref(iobref);
        }
        iobref = NULL;

        goto out;
    }

    GF_ASSERT(EC_ALIGN_CHECK(iobuf->ptr, EC_METHOD_WORD_SIZE));

    *ptr = iobuf->ptr;

out:
    if (iobuf != NULL) {
        iobuf_unref(iobuf);
    }

    if (iobref != NULL) {
        *piobref = iobref;
    }

    return ret;
}

int32_t
ec_dict_set_array(dict_t *dict, char *key, uint64_t value[], int32_t size)
{
    int ret = -1;
    uint64_t *ptr = NULL;
    int32_t vindex;

    if (value == NULL) {
        return -EINVAL;
    }

    ptr = GF_MALLOC(sizeof(uint64_t) * size, gf_common_mt_char);
    if (ptr == NULL) {
        return -ENOMEM;
    }
    for (vindex = 0; vindex < size; vindex++) {
        ptr[vindex] = hton64(value[vindex]);
    }
    ret = dict_set_bin(dict, key, ptr, sizeof(uint64_t) * size);
    if (ret)
        GF_FREE(ptr);
    return ret;
}

int32_t
ec_dict_get_array(dict_t *dict, char *key, uint64_t value[], int32_t size)
{
    void *ptr;
    int32_t len;
    int32_t vindex;
    int32_t old_size = 0;
    int32_t err;

    if (dict == NULL) {
        return -EINVAL;
    }
    err = dict_get_ptr_and_len(dict, key, &ptr, &len);
    if (err != 0) {
        return err;
    }

    if (len > (size * sizeof(uint64_t)) || (len % sizeof(uint64_t))) {
        return -EINVAL;
    }

    /* 3.6 version ec would have stored version in 64 bit. In that case treat
     * metadata versions same as data*/
    old_size = min(size, len / sizeof(uint64_t));
    for (vindex = 0; vindex < old_size; vindex++) {
        value[vindex] = ntoh64(*((uint64_t *)ptr + vindex));
    }

    if (old_size < size) {
        for (vindex = old_size; vindex < size; vindex++) {
            value[vindex] = value[old_size - 1];
        }
    }

    return 0;
}

int32_t
ec_dict_del_array(dict_t *dict, char *key, uint64_t value[], int32_t size)
{
    int ret = 0;

    ret = ec_dict_get_array(dict, key, value, size);
    if (ret == 0)
        dict_del(dict, key);

    return ret;
}

int32_t
ec_dict_set_number(dict_t *dict, char *key, uint64_t value)
{
    int ret = -1;
    uint64_t *ptr;

    ptr = GF_MALLOC(sizeof(value), gf_common_mt_char);
    if (ptr == NULL) {
        return -ENOMEM;
    }

    *ptr = hton64(value);

    ret = dict_set_bin(dict, key, ptr, sizeof(value));
    if (ret)
        GF_FREE(ptr);

    return ret;
}

int32_t
ec_dict_del_number(dict_t *dict, char *key, uint64_t *value)
{
    void *ptr;
    int32_t len, err;

    if (dict == NULL) {
        return -EINVAL;
    }
    err = dict_get_ptr_and_len(dict, key, &ptr, &len);
    if (err != 0) {
        return err;
    }
    if (len != sizeof(uint64_t)) {
        return -EINVAL;
    }

    *value = ntoh64(*(uint64_t *)ptr);

    dict_del(dict, key);

    return 0;
}

int32_t
ec_dict_set_config(dict_t *dict, char *key, ec_config_t *config)
{
    int ret = -1;
    uint64_t *ptr, data;

    if (config->version > EC_CONFIG_VERSION) {
        gf_msg("ec", GF_LOG_ERROR, EINVAL, EC_MSG_UNSUPPORTED_VERSION,
               "Trying to store an unsupported config "
               "version (%u)",
               config->version);

        return -EINVAL;
    }

    ptr = GF_MALLOC(sizeof(uint64_t), gf_common_mt_char);
    if (ptr == NULL) {
        return -ENOMEM;
    }

    data = ((uint64_t)config->version) << 56;
    data |= ((uint64_t)config->algorithm) << 48;
    data |= ((uint64_t)config->gf_word_size) << 40;
    data |= ((uint64_t)config->bricks) << 32;
    data |= ((uint64_t)config->redundancy) << 24;
    data |= config->chunk_size;

    *ptr = hton64(data);

    ret = dict_set_bin(dict, key, ptr, sizeof(uint64_t));
    if (ret)
        GF_FREE(ptr);

    return ret;
}

int32_t
ec_dict_del_config(dict_t *dict, char *key, ec_config_t *config)
{
    void *ptr;
    uint64_t data;
    int32_t len, err;

    if (dict == NULL) {
        return -EINVAL;
    }
    err = dict_get_ptr_and_len(dict, key, &ptr, &len);
    if (err != 0) {
        return err;
    }
    if (len != sizeof(uint64_t)) {
        return -EINVAL;
    }

    data = ntoh64(*(uint64_t *)ptr);
    /* Currently we need to get the config xattr for entries of type IA_INVAL.
     * These entries can later become IA_DIR entries (after inode_link()),
     * which don't have a config xattr. However, since the xattr is requested
     * using an xattrop() fop, it will always return a config full of 0's
     * instead of saying that it doesn't exist.
     *
     * We need to filter out this case and consider that a config xattr == 0 is
     * the same as a non-existent xattr. Otherwise ec_config_check() will fail.
     */
    if (data == 0) {
        return -ENODATA;
    }

    config->version = (data >> 56) & 0xff;
    if (config->version > EC_CONFIG_VERSION) {
        gf_msg("ec", GF_LOG_ERROR, EINVAL, EC_MSG_UNSUPPORTED_VERSION,
               "Found an unsupported config version (%u)", config->version);

        return -EINVAL;
    }

    config->algorithm = (data >> 48) & 0xff;
    config->gf_word_size = (data >> 40) & 0xff;
    config->bricks = (data >> 32) & 0xff;
    config->redundancy = (data >> 24) & 0xff;
    config->chunk_size = data & 0xffffff;

    dict_del(dict, key);

    return 0;
}

gf_boolean_t
ec_loc_gfid_check(xlator_t *xl, uuid_t dst, uuid_t src)
{
    if (gf_uuid_is_null(src)) {
        return _gf_true;
    }

    if (gf_uuid_is_null(dst)) {
        gf_uuid_copy(dst, src);

        return _gf_true;
    }

    if (gf_uuid_compare(dst, src) != 0) {
        gf_msg(xl->name, GF_LOG_WARNING, 0, EC_MSG_GFID_MISMATCH,
               "Mismatching GFID's in loc");

        return _gf_false;
    }

    return _gf_true;
}

int32_t
ec_loc_setup_inode(xlator_t *xl, inode_table_t *table, loc_t *loc)
{
    int32_t ret = -EINVAL;

    if (loc->inode != NULL) {
        if (!ec_loc_gfid_check(xl, loc->gfid, loc->inode->gfid)) {
            goto out;
        }
    } else if (table != NULL) {
        if (!gf_uuid_is_null(loc->gfid)) {
            loc->inode = inode_find(table, loc->gfid);
        } else if (loc->path && strchr(loc->path, '/')) {
            loc->inode = inode_resolve(table, (char *)loc->path);
        }
    }

    ret = 0;

out:
    return ret;
}

int32_t
ec_loc_setup_parent(xlator_t *xl, inode_table_t *table, loc_t *loc)
{
    char *path, *parent;
    int32_t ret = -EINVAL;

    if (loc->parent != NULL) {
        if (!ec_loc_gfid_check(xl, loc->pargfid, loc->parent->gfid)) {
            goto out;
        }
    } else if (table != NULL) {
        if (!gf_uuid_is_null(loc->pargfid)) {
            loc->parent = inode_find(table, loc->pargfid);
        } else if (loc->path && strchr(loc->path, '/')) {
            path = gf_strdup(loc->path);
            if (path == NULL) {
                gf_msg(xl->name, GF_LOG_ERROR, ENOMEM, EC_MSG_NO_MEMORY,
                       "Unable to duplicate path '%s'", loc->path);

                ret = -ENOMEM;

                goto out;
            }
            parent = dirname(path);
            loc->parent = inode_resolve(table, parent);
            if (loc->parent != NULL) {
                gf_uuid_copy(loc->pargfid, loc->parent->gfid);
            }
            GF_FREE(path);
        }
    }

    /* If 'pargfid' has not been determined, clear 'name' to avoid resolutions
       based on <gfid:pargfid>/name. */
    if (gf_uuid_is_null(loc->pargfid)) {
        loc->name = NULL;
    }

    ret = 0;

out:
    return ret;
}

int32_t
ec_loc_setup_path(xlator_t *xl, loc_t *loc)
{
    uuid_t root = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1};
    char *name;
    int32_t ret = -EINVAL;

    if (loc->path != NULL) {
        name = strrchr(loc->path, '/');
        if (name == NULL) {
            /* Allow gfid paths: <gfid:...> */
            if (strncmp(loc->path, "<gfid:", 6) == 0) {
                ret = 0;
            }
            goto out;
        }
        if (name == loc->path) {
            if (name[1] == 0) {
                if (!ec_loc_gfid_check(xl, loc->gfid, root)) {
                    goto out;
                }
            } else {
                if (!ec_loc_gfid_check(xl, loc->pargfid, root)) {
                    goto out;
                }
            }
        }
        name++;

        if (loc->name != NULL) {
            if (strcmp(loc->name, name) != 0) {
                gf_msg(xl->name, GF_LOG_ERROR, EINVAL, EC_MSG_INVALID_LOC_NAME,
                       "Invalid name '%s' in loc", loc->name);

                goto out;
            }
        } else {
            loc->name = name;
        }
    }

    ret = 0;

out:
    return ret;
}

int32_t
ec_loc_parent(xlator_t *xl, loc_t *loc, loc_t *parent)
{
    inode_table_t *table = NULL;
    char *str = NULL;
    int32_t ret = -ENOMEM;

    memset(parent, 0, sizeof(loc_t));

    if (loc->parent != NULL) {
        table = loc->parent->table;
        parent->inode = inode_ref(loc->parent);
    } else if (loc->inode != NULL) {
        table = loc->inode->table;
    }
    if (!gf_uuid_is_null(loc->pargfid)) {
        gf_uuid_copy(parent->gfid, loc->pargfid);
    }
    if (loc->path && strchr(loc->path, '/')) {
        str = gf_strdup(loc->path);
        if (str == NULL) {
            gf_msg(xl->name, GF_LOG_ERROR, ENOMEM, EC_MSG_NO_MEMORY,
                   "Unable to duplicate path '%s'", loc->path);

            goto out;
        }
        parent->path = gf_strdup(dirname(str));
        if (parent->path == NULL) {
            gf_msg(xl->name, GF_LOG_ERROR, ENOMEM, EC_MSG_NO_MEMORY,
                   "Unable to duplicate path '%s'", dirname(str));

            goto out;
        }
    }

    ret = ec_loc_setup_path(xl, parent);
    if (ret == 0) {
        ret = ec_loc_setup_inode(xl, table, parent);
    }
    if (ret == 0) {
        ret = ec_loc_setup_parent(xl, table, parent);
    }
    if (ret != 0) {
        goto out;
    }

    if ((parent->inode == NULL) && (parent->path == NULL) &&
        gf_uuid_is_null(parent->gfid)) {
        gf_msg(xl->name, GF_LOG_ERROR, EINVAL, EC_MSG_LOC_PARENT_INODE_MISSING,
               "Parent inode missing for loc_t");

        ret = -EINVAL;

        goto out;
    }

    ret = 0;

out:
    GF_FREE(str);

    if (ret != 0) {
        loc_wipe(parent);
    }

    return ret;
}

int32_t
ec_loc_update(xlator_t *xl, loc_t *loc, inode_t *inode, struct iatt *iatt)
{
    inode_table_t *table = NULL;
    int32_t ret = -EINVAL;

    if (inode != NULL) {
        table = inode->table;
        if (loc->inode != inode) {
            if (loc->inode != NULL) {
                inode_unref(loc->inode);
            }
            loc->inode = inode_ref(inode);
            gf_uuid_copy(loc->gfid, inode->gfid);
        }
    } else if (loc->inode != NULL) {
        table = loc->inode->table;
    } else if (loc->parent != NULL) {
        table = loc->parent->table;
    }

    if (iatt != NULL) {
        if (!ec_loc_gfid_check(xl, loc->gfid, iatt->ia_gfid)) {
            goto out;
        }
    }

    ret = ec_loc_setup_path(xl, loc);
    if (ret == 0) {
        ret = ec_loc_setup_inode(xl, table, loc);
    }
    if (ret == 0) {
        ret = ec_loc_setup_parent(xl, table, loc);
    }
    if (ret != 0) {
        goto out;
    }

out:
    return ret;
}

int32_t
ec_loc_from_fd(xlator_t *xl, loc_t *loc, fd_t *fd)
{
    ec_fd_t *ctx;
    int32_t ret = -ENOMEM;

    memset(loc, 0, sizeof(*loc));

    ctx = ec_fd_get(fd, xl);
    if (ctx != NULL) {
        if (loc_copy(loc, &ctx->loc) != 0) {
            goto out;
        }
    }

    ret = ec_loc_update(xl, loc, fd->inode, NULL);
    if (ret != 0) {
        goto out;
    }

out:
    if (ret != 0) {
        loc_wipe(loc);
    }

    return ret;
}

int32_t
ec_loc_from_loc(xlator_t *xl, loc_t *dst, loc_t *src)
{
    int32_t ret = -ENOMEM;

    memset(dst, 0, sizeof(*dst));

    if (loc_copy(dst, src) != 0) {
        goto out;
    }

    ret = ec_loc_update(xl, dst, NULL, NULL);
    if (ret != 0) {
        goto out;
    }

out:
    if (ret != 0) {
        loc_wipe(dst);
    }

    return ret;
}

void
ec_owner_set(call_frame_t *frame, void *owner)
{
    set_lk_owner_from_ptr(&frame->root->lk_owner, owner);
}

void
ec_owner_copy(call_frame_t *frame, gf_lkowner_t *owner)
{
    lk_owner_copy(&frame->root->lk_owner, owner);
}

static void
ec_stripe_cache_init(ec_t *ec, ec_inode_t *ctx)
{
    ec_stripe_list_t *stripe_cache = NULL;

    stripe_cache = &(ctx->stripe_cache);
    if (stripe_cache->max == 0) {
        stripe_cache->max = ec->stripe_cache;
    }
}

ec_inode_t *
__ec_inode_get(inode_t *inode, xlator_t *xl)
{
    ec_inode_t *ctx = NULL;
    uint64_t value = 0;

    if ((__inode_ctx_get(inode, xl, &value) != 0) || (value == 0)) {
        ctx = GF_MALLOC(sizeof(*ctx), ec_mt_ec_inode_t);
        if (ctx != NULL) {
            memset(ctx, 0, sizeof(*ctx));
            INIT_LIST_HEAD(&ctx->heal);
            INIT_LIST_HEAD(&ctx->stripe_cache.lru);
            value = (uint64_t)(uintptr_t)ctx;
            if (__inode_ctx_set(inode, xl, &value) != 0) {
                GF_FREE(ctx);

                return NULL;
            }
        }
    } else {
        ctx = (ec_inode_t *)(uintptr_t)value;
    }
    if (ctx)
        ec_stripe_cache_init(xl->private, ctx);

    return ctx;
}

ec_inode_t *
ec_inode_get(inode_t *inode, xlator_t *xl)
{
    ec_inode_t *ctx = NULL;

    LOCK(&inode->lock);

    ctx = __ec_inode_get(inode, xl);

    UNLOCK(&inode->lock);

    return ctx;
}

ec_fd_t *
__ec_fd_get(fd_t *fd, xlator_t *xl)
{
    int i = 0;
    ec_fd_t *ctx = NULL;
    uint64_t value = 0;
    ec_t *ec = xl->private;

    if ((__fd_ctx_get(fd, xl, &value) != 0) || (value == 0)) {
        ctx = GF_MALLOC(sizeof(*ctx) + (sizeof(ec_fd_status_t) * ec->nodes),
                        ec_mt_ec_fd_t);
        if (ctx != NULL) {
            memset(ctx, 0, sizeof(*ctx));

            for (i = 0; i < ec->nodes; i++) {
                if (fd_is_anonymous(fd)) {
                    ctx->fd_status[i] = EC_FD_OPENED;
                } else {
                    ctx->fd_status[i] = EC_FD_NOT_OPENED;
                }
            }

            value = (uint64_t)(uintptr_t)ctx;
            if (__fd_ctx_set(fd, xl, value) != 0) {
                GF_FREE(ctx);
                return NULL;
            }
        }
    } else {
        ctx = (ec_fd_t *)(uintptr_t)value;
    }

    /* Treat anonymous fd specially */
    if (fd->anonymous && ctx) {
        /* Mark the fd open for all subvolumes. */
        ctx->open = -1;
        /* Try to populate ctx->loc with fd->inode information. */
        ec_loc_update(xl, &ctx->loc, fd->inode, NULL);
    }

    return ctx;
}

ec_fd_t *
ec_fd_get(fd_t *fd, xlator_t *xl)
{
    ec_fd_t *ctx = NULL;

    LOCK(&fd->lock);

    ctx = __ec_fd_get(fd, xl);

    UNLOCK(&fd->lock);

    return ctx;
}

gf_boolean_t
ec_is_internal_xattr(dict_t *dict, char *key, data_t *value, void *data)
{
    if (key && (strncmp(key, EC_XATTR_PREFIX, SLEN(EC_XATTR_PREFIX)) == 0))
        return _gf_true;

    return _gf_false;
}

void
ec_filter_internal_xattrs(dict_t *xattr)
{
    dict_foreach_match(xattr, ec_is_internal_xattr, NULL,
                       dict_remove_foreach_fn, NULL);
}

gf_boolean_t
ec_is_data_fop(glusterfs_fop_t fop)
{
    switch (fop) {
        case GF_FOP_WRITE:
        case GF_FOP_TRUNCATE:
        case GF_FOP_FTRUNCATE:
        case GF_FOP_FALLOCATE:
        case GF_FOP_DISCARD:
        case GF_FOP_ZEROFILL:
            return _gf_true;
        default:
            return _gf_false;
    }
    return _gf_false;
}
/*
gf_boolean_t
ec_is_metadata_fop (int32_t lock_kind, glusterfs_fop_t fop)
{
        if (lock_kind == EC_LOCK_ENTRY) {
                return _gf_false;
        }

        switch (fop) {
        case GF_FOP_SETATTR:
        case GF_FOP_FSETATTR:
        case GF_FOP_SETXATTR:
        case GF_FOP_FSETXATTR:
        case GF_FOP_REMOVEXATTR:
        case GF_FOP_FREMOVEXATTR:
                return _gf_true;
        default:
                return _gf_false;
        }
        return _gf_false;
}*/