osdmap.c

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#include <linux/ceph/ceph_debug.h>

#include <linux/module.h>
#include <linux/slab.h>
#include <asm/div64.h>

#include <linux/ceph/libceph.h>
#include <linux/ceph/osdmap.h>
#include <linux/ceph/decode.h>
#include <linux/crush/hash.h>
#include <linux/crush/mapper.h>

char *ceph_osdmap_state_str(char *str, int len, int state)
{
    int flag = 0;

    if (!len)
        goto done;

    *str = '\0';
    if (state) {
        if (state & CEPH_OSD_EXISTS) {
            snprintf(str, len, "exists");
            flag = 1;
        }
        if (state & CEPH_OSD_UP) {
            snprintf(str, len, "%s%s%s", str, (flag ? ", " : ""),
                 "up");
            flag = 1;
        }
    } else {
        snprintf(str, len, "doesn't exist");
    }
done:
    return str;
}

/* maps */

static int calc_bits_of(unsigned int t)
{
    int b = 0;
    while (t) {
        t = t >> 1;
        b++;
    }
    return b;
}

/*
 * the foo_mask is the smallest value 2^n-1 that is >= foo.
 */
static void calc_pg_masks(struct ceph_pg_pool_info *pi)
{
    pi->pg_num_mask = (1 << calc_bits_of(le32_to_cpu(pi->v.pg_num)-1)) - 1;
    pi->pgp_num_mask =
        (1 << calc_bits_of(le32_to_cpu(pi->v.pgp_num)-1)) - 1;
    pi->lpg_num_mask =
        (1 << calc_bits_of(le32_to_cpu(pi->v.lpg_num)-1)) - 1;
    pi->lpgp_num_mask =
        (1 << calc_bits_of(le32_to_cpu(pi->v.lpgp_num)-1)) - 1;
}

/*
 * decode crush map
 */
static int crush_decode_uniform_bucket(void **p, void *end,
                       struct crush_bucket_uniform *b)
{
    dout("crush_decode_uniform_bucket %p to %p\n", *p, end);
    ceph_decode_need(p, end, (1+b->h.size) * sizeof(u32), bad);
    b->item_weight = ceph_decode_32(p);
    return 0;
bad:
    return -EINVAL;
}

static int crush_decode_list_bucket(void **p, void *end,
                    struct crush_bucket_list *b)
{
    int j;
    dout("crush_decode_list_bucket %p to %p\n", *p, end);
    b->item_weights = kcalloc(b->h.size, sizeof(u32), GFP_NOFS);
    if (b->item_weights == NULL)
        return -ENOMEM;
    b->sum_weights = kcalloc(b->h.size, sizeof(u32), GFP_NOFS);
    if (b->sum_weights == NULL)
        return -ENOMEM;
    ceph_decode_need(p, end, 2 * b->h.size * sizeof(u32), bad);
    for (j = 0; j < b->h.size; j++) {
        b->item_weights[j] = ceph_decode_32(p);
        b->sum_weights[j] = ceph_decode_32(p);
    }
    return 0;
bad:
    return -EINVAL;
}

static int crush_decode_tree_bucket(void **p, void *end,
                    struct crush_bucket_tree *b)
{
    int j;
    dout("crush_decode_tree_bucket %p to %p\n", *p, end);
    ceph_decode_32_safe(p, end, b->num_nodes, bad);
    b->node_weights = kcalloc(b->num_nodes, sizeof(u32), GFP_NOFS);
    if (b->node_weights == NULL)
        return -ENOMEM;
    ceph_decode_need(p, end, b->num_nodes * sizeof(u32), bad);
    for (j = 0; j < b->num_nodes; j++)
        b->node_weights[j] = ceph_decode_32(p);
    return 0;
bad:
    return -EINVAL;
}

static int crush_decode_straw_bucket(void **p, void *end,
                     struct crush_bucket_straw *b)
{
    int j;
    dout("crush_decode_straw_bucket %p to %p\n", *p, end);
    b->item_weights = kcalloc(b->h.size, sizeof(u32), GFP_NOFS);
    if (b->item_weights == NULL)
        return -ENOMEM;
    b->straws = kcalloc(b->h.size, sizeof(u32), GFP_NOFS);
    if (b->straws == NULL)
        return -ENOMEM;
    ceph_decode_need(p, end, 2 * b->h.size * sizeof(u32), bad);
    for (j = 0; j < b->h.size; j++) {
        b->item_weights[j] = ceph_decode_32(p);
        b->straws[j] = ceph_decode_32(p);
    }
    return 0;
bad:
    return -EINVAL;
}

static int skip_name_map(void **p, void *end)
{
        int len;
        ceph_decode_32_safe(p, end, len ,bad);
        while (len--) {
                int strlen;
                *p += sizeof(u32);
                ceph_decode_32_safe(p, end, strlen, bad);
                *p += strlen;
}
        return 0;
bad:
        return -EINVAL;
}

static struct crush_map *crush_decode(void *pbyval, void *end)
{
    struct crush_map *c;
    int err = -EINVAL;
    int i, j;
    void **p = &pbyval;
    void *start = pbyval;
    u32 magic;
    u32 num_name_maps;

    dout("crush_decode %p to %p len %d\n", *p, end, (int)(end - *p));

    c = kzalloc(sizeof(*c), GFP_NOFS);
    if (c == NULL)
        return ERR_PTR(-ENOMEM);

        /* set tunables to default values */
        c->choose_local_tries = 2;
        c->choose_local_fallback_tries = 5;
        c->choose_total_tries = 19;

    ceph_decode_need(p, end, 4*sizeof(u32), bad);
    magic = ceph_decode_32(p);
    if (magic != CRUSH_MAGIC) {
        pr_err("crush_decode magic %x != current %x\n",
               (unsigned int)magic, (unsigned int)CRUSH_MAGIC);
        goto bad;
    }
    c->max_buckets = ceph_decode_32(p);
    c->max_rules = ceph_decode_32(p);
    c->max_devices = ceph_decode_32(p);

    c->buckets = kcalloc(c->max_buckets, sizeof(*c->buckets), GFP_NOFS);
    if (c->buckets == NULL)
        goto badmem;
    c->rules = kcalloc(c->max_rules, sizeof(*c->rules), GFP_NOFS);
    if (c->rules == NULL)
        goto badmem;

    /* buckets */
    for (i = 0; i < c->max_buckets; i++) {
        int size = 0;
        u32 alg;
        struct crush_bucket *b;

        ceph_decode_32_safe(p, end, alg, bad);
        if (alg == 0) {
            c->buckets[i] = NULL;
            continue;
        }
        dout("crush_decode bucket %d off %x %p to %p\n",
             i, (int)(*p-start), *p, end);

        switch (alg) {
        case CRUSH_BUCKET_UNIFORM:
            size = sizeof(struct crush_bucket_uniform);
            break;
        case CRUSH_BUCKET_LIST:
            size = sizeof(struct crush_bucket_list);
            break;
        case CRUSH_BUCKET_TREE:
            size = sizeof(struct crush_bucket_tree);
            break;
        case CRUSH_BUCKET_STRAW:
            size = sizeof(struct crush_bucket_straw);
            break;
        default:
            err = -EINVAL;
            goto bad;
        }
        BUG_ON(size == 0);
        b = c->buckets[i] = kzalloc(size, GFP_NOFS);
        if (b == NULL)
            goto badmem;

        ceph_decode_need(p, end, 4*sizeof(u32), bad);
        b->id = ceph_decode_32(p);
        b->type = ceph_decode_16(p);
        b->alg = ceph_decode_8(p);
        b->hash = ceph_decode_8(p);
        b->weight = ceph_decode_32(p);
        b->size = ceph_decode_32(p);

        dout("crush_decode bucket size %d off %x %p to %p\n",
             b->size, (int)(*p-start), *p, end);

        b->items = kcalloc(b->size, sizeof(__s32), GFP_NOFS);
        if (b->items == NULL)
            goto badmem;
        b->perm = kcalloc(b->size, sizeof(u32), GFP_NOFS);
        if (b->perm == NULL)
            goto badmem;
        b->perm_n = 0;

        ceph_decode_need(p, end, b->size*sizeof(u32), bad);
        for (j = 0; j < b->size; j++)
            b->items[j] = ceph_decode_32(p);

        switch (b->alg) {
        case CRUSH_BUCKET_UNIFORM:
            err = crush_decode_uniform_bucket(p, end,
                  (struct crush_bucket_uniform *)b);
            if (err < 0)
                goto bad;
            break;
        case CRUSH_BUCKET_LIST:
            err = crush_decode_list_bucket(p, end,
                   (struct crush_bucket_list *)b);
            if (err < 0)
                goto bad;
            break;
        case CRUSH_BUCKET_TREE:
            err = crush_decode_tree_bucket(p, end,
                (struct crush_bucket_tree *)b);
            if (err < 0)
                goto bad;
            break;
        case CRUSH_BUCKET_STRAW:
            err = crush_decode_straw_bucket(p, end,
                (struct crush_bucket_straw *)b);
            if (err < 0)
                goto bad;
            break;
        }
    }

    /* rules */
    dout("rule vec is %p\n", c->rules);
    for (i = 0; i < c->max_rules; i++) {
        u32 yes;
        struct crush_rule *r;

        ceph_decode_32_safe(p, end, yes, bad);
        if (!yes) {
            dout("crush_decode NO rule %d off %x %p to %p\n",
                 i, (int)(*p-start), *p, end);
            c->rules[i] = NULL;
            continue;
        }

        dout("crush_decode rule %d off %x %p to %p\n",
             i, (int)(*p-start), *p, end);

        /* len */
        ceph_decode_32_safe(p, end, yes, bad);
#if BITS_PER_LONG == 32
        err = -EINVAL;
        if (yes > (ULONG_MAX - sizeof(*r))
              / sizeof(struct crush_rule_step))
            goto bad;
#endif
        r = c->rules[i] = kmalloc(sizeof(*r) +
                      yes*sizeof(struct crush_rule_step),
                      GFP_NOFS);
        if (r == NULL)
            goto badmem;
        dout(" rule %d is at %p\n", i, r);
        r->len = yes;
        ceph_decode_copy_safe(p, end, &r->mask, 4, bad); /* 4 u8's */
        ceph_decode_need(p, end, r->len*3*sizeof(u32), bad);
        for (j = 0; j < r->len; j++) {
            r->steps[j].op = ceph_decode_32(p);
            r->steps[j].arg1 = ceph_decode_32(p);
            r->steps[j].arg2 = ceph_decode_32(p);
        }
    }

    /* ignore trailing name maps. */
        for (num_name_maps = 0; num_name_maps < 3; num_name_maps++) {
                err = skip_name_map(p, end);
                if (err < 0)
                        goto done;
        }

        /* tunables */
        ceph_decode_need(p, end, 3*sizeof(u32), done);
        c->choose_local_tries = ceph_decode_32(p);
        c->choose_local_fallback_tries =  ceph_decode_32(p);
        c->choose_total_tries = ceph_decode_32(p);
        dout("crush decode tunable choose_local_tries = %d",
             c->choose_local_tries);
        dout("crush decode tunable choose_local_fallback_tries = %d",
             c->choose_local_fallback_tries);
        dout("crush decode tunable choose_total_tries = %d",
             c->choose_total_tries);

done:
    dout("crush_decode success\n");
    return c;

badmem:
    err = -ENOMEM;
bad:
    dout("crush_decode fail %d\n", err);
    crush_destroy(c);
    return ERR_PTR(err);
}

/*
 * rbtree of pg_mapping for handling pg_temp (explicit mapping of pgid
 * to a set of osds)
 */
static int pgid_cmp(struct ceph_pg l, struct ceph_pg r)
{
    u64 a = *(u64 *)&l;
    u64 b = *(u64 *)&r;

    if (a < b)
        return -1;
    if (a > b)
        return 1;
    return 0;
}

static int __insert_pg_mapping(struct ceph_pg_mapping *new,
                   struct rb_root *root)
{
    struct rb_node **p = &root->rb_node;
    struct rb_node *parent = NULL;
    struct ceph_pg_mapping *pg = NULL;
    int c;

    dout("__insert_pg_mapping %llx %p\n", *(u64 *)&new->pgid, new);
    while (*p) {
        parent = *p;
        pg = rb_entry(parent, struct ceph_pg_mapping, node);
        c = pgid_cmp(new->pgid, pg->pgid);
        if (c < 0)
            p = &(*p)->rb_left;
        else if (c > 0)
            p = &(*p)->rb_right;
        else
            return -EEXIST;
    }

    rb_link_node(&new->node, parent, p);
    rb_insert_color(&new->node, root);
    return 0;
}

static struct ceph_pg_mapping *__lookup_pg_mapping(struct rb_root *root,
                           struct ceph_pg pgid)
{
    struct rb_node *n = root->rb_node;
    struct ceph_pg_mapping *pg;
    int c;

    while (n) {
        pg = rb_entry(n, struct ceph_pg_mapping, node);
        c = pgid_cmp(pgid, pg->pgid);
        if (c < 0) {
            n = n->rb_left;
        } else if (c > 0) {
            n = n->rb_right;
        } else {
            dout("__lookup_pg_mapping %llx got %p\n",
                 *(u64 *)&pgid, pg);
            return pg;
        }
    }
    return NULL;
}

static int __remove_pg_mapping(struct rb_root *root, struct ceph_pg pgid)
{
    struct ceph_pg_mapping *pg = __lookup_pg_mapping(root, pgid);

    if (pg) {
        dout("__remove_pg_mapping %llx %p\n", *(u64 *)&pgid, pg);
        rb_erase(&pg->node, root);
        kfree(pg);
        return 0;
    }
    dout("__remove_pg_mapping %llx dne\n", *(u64 *)&pgid);
    return -ENOENT;
}

/*
 * rbtree of pg pool info
 */
static int __insert_pg_pool(struct rb_root *root, struct ceph_pg_pool_info *new)
{
    struct rb_node **p = &root->rb_node;
    struct rb_node *parent = NULL;
    struct ceph_pg_pool_info *pi = NULL;

    while (*p) {
        parent = *p;
        pi = rb_entry(parent, struct ceph_pg_pool_info, node);
        if (new->id < pi->id)
            p = &(*p)->rb_left;
        else if (new->id > pi->id)
            p = &(*p)->rb_right;
        else
            return -EEXIST;
    }

    rb_link_node(&new->node, parent, p);
    rb_insert_color(&new->node, root);
    return 0;
}

static struct ceph_pg_pool_info *__lookup_pg_pool(struct rb_root *root, int id)
{
    struct ceph_pg_pool_info *pi;
    struct rb_node *n = root->rb_node;

    while (n) {
        pi = rb_entry(n, struct ceph_pg_pool_info, node);
        if (id < pi->id)
            n = n->rb_left;
        else if (id > pi->id)
            n = n->rb_right;
        else
            return pi;
    }
    return NULL;
}

int ceph_pg_poolid_by_name(struct ceph_osdmap *map, const char *name)
{
    struct rb_node *rbp;

    for (rbp = rb_first(&map->pg_pools); rbp; rbp = rb_next(rbp)) {
        struct ceph_pg_pool_info *pi =
            rb_entry(rbp, struct ceph_pg_pool_info, node);
        if (pi->name && strcmp(pi->name, name) == 0)
            return pi->id;
    }
    return -ENOENT;
}
EXPORT_SYMBOL(ceph_pg_poolid_by_name);

static void __remove_pg_pool(struct rb_root *root, struct ceph_pg_pool_info *pi)
{
    rb_erase(&pi->node, root);
    kfree(pi->name);
    kfree(pi);
}

static int __decode_pool(void **p, void *end, struct ceph_pg_pool_info *pi)
{
    unsigned int n, m;

    ceph_decode_copy(p, &pi->v, sizeof(pi->v));
    calc_pg_masks(pi);

    /* num_snaps * snap_info_t */
    n = le32_to_cpu(pi->v.num_snaps);
    while (n--) {
        ceph_decode_need(p, end, sizeof(u64) + 1 + sizeof(u64) +
                 sizeof(struct ceph_timespec), bad);
        *p += sizeof(u64) +       /* key */
            1 + sizeof(u64) + /* u8, snapid */
            sizeof(struct ceph_timespec);
        m = ceph_decode_32(p);    /* snap name */
        *p += m;
    }

    *p += le32_to_cpu(pi->v.num_removed_snap_intervals) * sizeof(u64) * 2;
    return 0;

bad:
    return -EINVAL;
}

static int __decode_pool_names(void **p, void *end, struct ceph_osdmap *map)
{
    struct ceph_pg_pool_info *pi;
    u32 num, len, pool;

    ceph_decode_32_safe(p, end, num, bad);
    dout(" %d pool names\n", num);
    while (num--) {
        ceph_decode_32_safe(p, end, pool, bad);
        ceph_decode_32_safe(p, end, len, bad);
        dout("  pool %d len %d\n", pool, len);
        ceph_decode_need(p, end, len, bad);
        pi = __lookup_pg_pool(&map->pg_pools, pool);
        if (pi) {
            char *name = kstrndup(*p, len, GFP_NOFS);

            if (!name)
                return -ENOMEM;
            kfree(pi->name);
            pi->name = name;
            dout("  name is %s\n", pi->name);
        }
        *p += len;
    }
    return 0;

bad:
    return -EINVAL;
}

/*
 * osd map
 */
void ceph_osdmap_destroy(struct ceph_osdmap *map)
{
    dout("osdmap_destroy %p\n", map);
    if (map->crush)
        crush_destroy(map->crush);
    while (!RB_EMPTY_ROOT(&map->pg_temp)) {
        struct ceph_pg_mapping *pg =
            rb_entry(rb_first(&map->pg_temp),
                 struct ceph_pg_mapping, node);
        rb_erase(&pg->node, &map->pg_temp);
        kfree(pg);
    }
    while (!RB_EMPTY_ROOT(&map->pg_pools)) {
        struct ceph_pg_pool_info *pi =
            rb_entry(rb_first(&map->pg_pools),
                 struct ceph_pg_pool_info, node);
        __remove_pg_pool(&map->pg_pools, pi);
    }
    kfree(map->osd_state);
    kfree(map->osd_weight);
    kfree(map->osd_addr);
    kfree(map);
}

/*
 * adjust max osd value.  reallocate arrays.
 */
static int osdmap_set_max_osd(struct ceph_osdmap *map, int max)
{
    u8 *state;
    struct ceph_entity_addr *addr;
    u32 *weight;

    state = kcalloc(max, sizeof(*state), GFP_NOFS);
    addr = kcalloc(max, sizeof(*addr), GFP_NOFS);
    weight = kcalloc(max, sizeof(*weight), GFP_NOFS);
    if (state == NULL || addr == NULL || weight == NULL) {
        kfree(state);
        kfree(addr);
        kfree(weight);
        return -ENOMEM;
    }

    /* copy old? */
    if (map->osd_state) {
        memcpy(state, map->osd_state, map->max_osd*sizeof(*state));
        memcpy(addr, map->osd_addr, map->max_osd*sizeof(*addr));
        memcpy(weight, map->osd_weight, map->max_osd*sizeof(*weight));
        kfree(map->osd_state);
        kfree(map->osd_addr);
        kfree(map->osd_weight);
    }

    map->osd_state = state;
    map->osd_weight = weight;
    map->osd_addr = addr;
    map->max_osd = max;
    return 0;
}

/*
 * decode a full map.
 */
struct ceph_osdmap *osdmap_decode(void **p, void *end)
{
    struct ceph_osdmap *map;
    u16 version;
    u32 len, max, i;
    u8 ev;
    int err = -EINVAL;
    void *start = *p;
    struct ceph_pg_pool_info *pi;

    dout("osdmap_decode %p to %p len %d\n", *p, end, (int)(end - *p));

    map = kzalloc(sizeof(*map), GFP_NOFS);
    if (map == NULL)
        return ERR_PTR(-ENOMEM);
    map->pg_temp = RB_ROOT;

    ceph_decode_16_safe(p, end, version, bad);
    if (version > CEPH_OSDMAP_VERSION) {
        pr_warning("got unknown v %d > %d of osdmap\n", version,
               CEPH_OSDMAP_VERSION);
        goto bad;
    }

    ceph_decode_need(p, end, 2*sizeof(u64)+6*sizeof(u32), bad);
    ceph_decode_copy(p, &map->fsid, sizeof(map->fsid));
    map->epoch = ceph_decode_32(p);
    ceph_decode_copy(p, &map->created, sizeof(map->created));
    ceph_decode_copy(p, &map->modified, sizeof(map->modified));

    ceph_decode_32_safe(p, end, max, bad);
    while (max--) {
        ceph_decode_need(p, end, 4 + 1 + sizeof(pi->v), bad);
        pi = kzalloc(sizeof(*pi), GFP_NOFS);
        if (!pi)
            goto bad;
        pi->id = ceph_decode_32(p);
        ev = ceph_decode_8(p); /* encoding version */
        if (ev > CEPH_PG_POOL_VERSION) {
            pr_warning("got unknown v %d > %d of ceph_pg_pool\n",
                   ev, CEPH_PG_POOL_VERSION);
            kfree(pi);
            goto bad;
        }
        err = __decode_pool(p, end, pi);
        if (err < 0) {
            kfree(pi);
            goto bad;
        }
        __insert_pg_pool(&map->pg_pools, pi);
    }

    if (version >= 5 && __decode_pool_names(p, end, map) < 0)
        goto bad;

    ceph_decode_32_safe(p, end, map->pool_max, bad);

    ceph_decode_32_safe(p, end, map->flags, bad);

    max = ceph_decode_32(p);

    /* (re)alloc osd arrays */
    err = osdmap_set_max_osd(map, max);
    if (err < 0)
        goto bad;
    dout("osdmap_decode max_osd = %d\n", map->max_osd);

    /* osds */
    err = -EINVAL;
    ceph_decode_need(p, end, 3*sizeof(u32) +
             map->max_osd*(1 + sizeof(*map->osd_weight) +
                       sizeof(*map->osd_addr)), bad);
    *p += 4; /* skip length field (should match max) */
    ceph_decode_copy(p, map->osd_state, map->max_osd);

    *p += 4; /* skip length field (should match max) */
    for (i = 0; i < map->max_osd; i++)
        map->osd_weight[i] = ceph_decode_32(p);

    *p += 4; /* skip length field (should match max) */
    ceph_decode_copy(p, map->osd_addr, map->max_osd*sizeof(*map->osd_addr));
    for (i = 0; i < map->max_osd; i++)
        ceph_decode_addr(&map->osd_addr[i]);

    /* pg_temp */
    ceph_decode_32_safe(p, end, len, bad);
    for (i = 0; i < len; i++) {
        int n, j;
        struct ceph_pg pgid;
        struct ceph_pg_mapping *pg;

        ceph_decode_need(p, end, sizeof(u32) + sizeof(u64), bad);
        ceph_decode_copy(p, &pgid, sizeof(pgid));
        n = ceph_decode_32(p);
        err = -EINVAL;
        if (n > (UINT_MAX - sizeof(*pg)) / sizeof(u32))
            goto bad;
        ceph_decode_need(p, end, n * sizeof(u32), bad);
        err = -ENOMEM;
        pg = kmalloc(sizeof(*pg) + n*sizeof(u32), GFP_NOFS);
        if (!pg)
            goto bad;
        pg->pgid = pgid;
        pg->len = n;
        for (j = 0; j < n; j++)
            pg->osds[j] = ceph_decode_32(p);

        err = __insert_pg_mapping(pg, &map->pg_temp);
        if (err)
            goto bad;
        dout(" added pg_temp %llx len %d\n", *(u64 *)&pgid, len);
    }

    /* crush */
    ceph_decode_32_safe(p, end, len, bad);
    dout("osdmap_decode crush len %d from off 0x%x\n", len,
         (int)(*p - start));
    ceph_decode_need(p, end, len, bad);
    map->crush = crush_decode(*p, end);
    *p += len;
    if (IS_ERR(map->crush)) {
        err = PTR_ERR(map->crush);
        map->crush = NULL;
        goto bad;
    }

    /* ignore the rest of the map */
    *p = end;

    dout("osdmap_decode done %p %p\n", *p, end);
    return map;

bad:
    dout("osdmap_decode fail\n");
    ceph_osdmap_destroy(map);
    return ERR_PTR(err);
}

/*
 * decode and apply an incremental map update.
 */
struct ceph_osdmap *osdmap_apply_incremental(void **p, void *end,
                         struct ceph_osdmap *map,
                         struct ceph_messenger *msgr)
{
    struct crush_map *newcrush = NULL;
    struct ceph_fsid fsid;
    u32 epoch = 0;
    struct ceph_timespec modified;
    u32 len, pool;
    __s32 new_pool_max, new_flags, max;
    void *start = *p;
    int err = -EINVAL;
    u16 version;

    ceph_decode_16_safe(p, end, version, bad);
    if (version > CEPH_OSDMAP_INC_VERSION) {
        pr_warning("got unknown v %d > %d of inc osdmap\n", version,
               CEPH_OSDMAP_INC_VERSION);
        goto bad;
    }

    ceph_decode_need(p, end, sizeof(fsid)+sizeof(modified)+2*sizeof(u32),
             bad);
    ceph_decode_copy(p, &fsid, sizeof(fsid));
    epoch = ceph_decode_32(p);
    BUG_ON(epoch != map->epoch+1);
    ceph_decode_copy(p, &modified, sizeof(modified));
    new_pool_max = ceph_decode_32(p);
    new_flags = ceph_decode_32(p);

    /* full map? */
    ceph_decode_32_safe(p, end, len, bad);
    if (len > 0) {
        dout("apply_incremental full map len %d, %p to %p\n",
             len, *p, end);
        return osdmap_decode(p, min(*p+len, end));
    }

    /* new crush? */
    ceph_decode_32_safe(p, end, len, bad);
    if (len > 0) {
        dout("apply_incremental new crush map len %d, %p to %p\n",
             len, *p, end);
        newcrush = crush_decode(*p, min(*p+len, end));
        if (IS_ERR(newcrush))
            return ERR_CAST(newcrush);
        *p += len;
    }

    /* new flags? */
    if (new_flags >= 0)
        map->flags = new_flags;
    if (new_pool_max >= 0)
        map->pool_max = new_pool_max;

    ceph_decode_need(p, end, 5*sizeof(u32), bad);

    /* new max? */
    max = ceph_decode_32(p);
    if (max >= 0) {
        err = osdmap_set_max_osd(map, max);
        if (err < 0)
            goto bad;
    }

    map->epoch++;
    map->modified = modified;
    if (newcrush) {
        if (map->crush)
            crush_destroy(map->crush);
        map->crush = newcrush;
        newcrush = NULL;
    }

    /* new_pool */
    ceph_decode_32_safe(p, end, len, bad);
    while (len--) {
        __u8 ev;
        struct ceph_pg_pool_info *pi;

        ceph_decode_32_safe(p, end, pool, bad);
        ceph_decode_need(p, end, 1 + sizeof(pi->v), bad);
        ev = ceph_decode_8(p);  /* encoding version */
        if (ev > CEPH_PG_POOL_VERSION) {
            pr_warning("got unknown v %d > %d of ceph_pg_pool\n",
                   ev, CEPH_PG_POOL_VERSION);
            goto bad;
        }
        pi = __lookup_pg_pool(&map->pg_pools, pool);
        if (!pi) {
            pi = kzalloc(sizeof(*pi), GFP_NOFS);
            if (!pi) {
                err = -ENOMEM;
                goto bad;
            }
            pi->id = pool;
            __insert_pg_pool(&map->pg_pools, pi);
        }
        err = __decode_pool(p, end, pi);
        if (err < 0)
            goto bad;
    }
    if (version >= 5 && __decode_pool_names(p, end, map) < 0)
        goto bad;

    /* old_pool */
    ceph_decode_32_safe(p, end, len, bad);
    while (len--) {
        struct ceph_pg_pool_info *pi;

        ceph_decode_32_safe(p, end, pool, bad);
        pi = __lookup_pg_pool(&map->pg_pools, pool);
        if (pi)
            __remove_pg_pool(&map->pg_pools, pi);
    }

    /* new_up */
    err = -EINVAL;
    ceph_decode_32_safe(p, end, len, bad);
    while (len--) {
        u32 osd;
        struct ceph_entity_addr addr;
        ceph_decode_32_safe(p, end, osd, bad);
        ceph_decode_copy_safe(p, end, &addr, sizeof(addr), bad);
        ceph_decode_addr(&addr);
        pr_info("osd%d up\n", osd);
        BUG_ON(osd >= map->max_osd);
        map->osd_state[osd] |= CEPH_OSD_UP;
        map->osd_addr[osd] = addr;
    }

    /* new_state */
    ceph_decode_32_safe(p, end, len, bad);
    while (len--) {
        u32 osd;
        u8 xorstate;
        ceph_decode_32_safe(p, end, osd, bad);
        xorstate = **(u8 **)p;
        (*p)++;  /* clean flag */
        if (xorstate == 0)
            xorstate = CEPH_OSD_UP;
        if (xorstate & CEPH_OSD_UP)
            pr_info("osd%d down\n", osd);
        if (osd < map->max_osd)
            map->osd_state[osd] ^= xorstate;
    }

    /* new_weight */
    ceph_decode_32_safe(p, end, len, bad);
    while (len--) {
        u32 osd, off;
        ceph_decode_need(p, end, sizeof(u32)*2, bad);
        osd = ceph_decode_32(p);
        off = ceph_decode_32(p);
        pr_info("osd%d weight 0x%x %s\n", osd, off,
             off == CEPH_OSD_IN ? "(in)" :
             (off == CEPH_OSD_OUT ? "(out)" : ""));
        if (osd < map->max_osd)
            map->osd_weight[osd] = off;
    }

    /* new_pg_temp */
    ceph_decode_32_safe(p, end, len, bad);
    while (len--) {
        struct ceph_pg_mapping *pg;
        int j;
        struct ceph_pg pgid;
        u32 pglen;
        ceph_decode_need(p, end, sizeof(u64) + sizeof(u32), bad);
        ceph_decode_copy(p, &pgid, sizeof(pgid));
        pglen = ceph_decode_32(p);

        if (pglen) {
            ceph_decode_need(p, end, pglen*sizeof(u32), bad);

            /* removing existing (if any) */
            (void) __remove_pg_mapping(&map->pg_temp, pgid);

            /* insert */
            if (pglen > (UINT_MAX - sizeof(*pg)) / sizeof(u32)) {
                err = -EINVAL;
                goto bad;
            }
            pg = kmalloc(sizeof(*pg) + sizeof(u32)*pglen, GFP_NOFS);
            if (!pg) {
                err = -ENOMEM;
                goto bad;
            }
            pg->pgid = pgid;
            pg->len = pglen;
            for (j = 0; j < pglen; j++)
                pg->osds[j] = ceph_decode_32(p);
            err = __insert_pg_mapping(pg, &map->pg_temp);
            if (err) {
                kfree(pg);
                goto bad;
            }
            dout(" added pg_temp %llx len %d\n", *(u64 *)&pgid,
                 pglen);
        } else {
            /* remove */
            __remove_pg_mapping(&map->pg_temp, pgid);
        }
    }

    /* ignore the rest */
    *p = end;
    return map;

bad:
    pr_err("corrupt inc osdmap epoch %d off %d (%p of %p-%p)\n",
           epoch, (int)(*p - start), *p, start, end);
    print_hex_dump(KERN_DEBUG, "osdmap: ",
               DUMP_PREFIX_OFFSET, 16, 1,
               start, end - start, true);
    if (newcrush)
        crush_destroy(newcrush);
    return ERR_PTR(err);
}




/*
 * calculate file layout from given offset, length.
 * fill in correct oid, logical length, and object extent
 * offset, length.
 *
 * for now, we write only a single su, until we can
 * pass a stride back to the caller.
 */
int ceph_calc_file_object_mapping(struct ceph_file_layout *layout,
                   u64 off, u64 *plen,
                   u64 *ono,
                   u64 *oxoff, u64 *oxlen)
{
    u32 osize = le32_to_cpu(layout->fl_object_size);
    u32 su = le32_to_cpu(layout->fl_stripe_unit);
    u32 sc = le32_to_cpu(layout->fl_stripe_count);
    u32 bl, stripeno, stripepos, objsetno;
    u32 su_per_object;
    u64 t, su_offset;

    dout("mapping %llu~%llu  osize %u fl_su %u\n", off, *plen,
         osize, su);
    if (su == 0 || sc == 0)
        goto invalid;
    su_per_object = osize / su;
    if (su_per_object == 0)
        goto invalid;
    dout("osize %u / su %u = su_per_object %u\n", osize, su,
         su_per_object);

    if ((su & ~PAGE_MASK) != 0)
        goto invalid;

    /* bl = *off / su; */
    t = off;
    do_div(t, su);
    bl = t;
    dout("off %llu / su %u = bl %u\n", off, su, bl);

    stripeno = bl / sc;
    stripepos = bl % sc;
    objsetno = stripeno / su_per_object;

    *ono = objsetno * sc + stripepos;
    dout("objset %u * sc %u = ono %u\n", objsetno, sc, (unsigned int)*ono);

    /* *oxoff = *off % layout->fl_stripe_unit;  # offset in su */
    t = off;
    su_offset = do_div(t, su);
    *oxoff = su_offset + (stripeno % su_per_object) * su;

    /*
     * Calculate the length of the extent being written to the selected
     * object. This is the minimum of the full length requested (plen) or
     * the remainder of the current stripe being written to.
     */
    *oxlen = min_t(u64, *plen, su - su_offset);
    *plen = *oxlen;

    dout(" obj extent %llu~%llu\n", *oxoff, *oxlen);
    return 0;

invalid:
    dout(" invalid layout\n");
    *ono = 0;
    *oxoff = 0;
    *oxlen = 0;
    return -EINVAL;
}
EXPORT_SYMBOL(ceph_calc_file_object_mapping);

/*
 * calculate an object layout (i.e. pgid) from an oid,
 * file_layout, and osdmap
 */
int ceph_calc_object_layout(struct ceph_object_layout *ol,
                const char *oid,
                struct ceph_file_layout *fl,
                struct ceph_osdmap *osdmap)
{
    unsigned int num, num_mask;
    struct ceph_pg pgid;
    int poolid = le32_to_cpu(fl->fl_pg_pool);
    struct ceph_pg_pool_info *pool;
    unsigned int ps;

    BUG_ON(!osdmap);

    pool = __lookup_pg_pool(&osdmap->pg_pools, poolid);
    if (!pool)
        return -EIO;
    ps = ceph_str_hash(pool->v.object_hash, oid, strlen(oid));
    num = le32_to_cpu(pool->v.pg_num);
    num_mask = pool->pg_num_mask;

    pgid.ps = cpu_to_le16(ps);
    pgid.preferred = cpu_to_le16(-1);
    pgid.pool = fl->fl_pg_pool;
    dout("calc_object_layout '%s' pgid %d.%x\n", oid, poolid, ps);

    ol->ol_pgid = pgid;
    ol->ol_stripe_unit = fl->fl_object_stripe_unit;
    return 0;
}
EXPORT_SYMBOL(ceph_calc_object_layout);

/*
 * Calculate raw osd vector for the given pgid.  Return pointer to osd
 * array, or NULL on failure.
 */
static int *calc_pg_raw(struct ceph_osdmap *osdmap, struct ceph_pg pgid,
            int *osds, int *num)
{
    struct ceph_pg_mapping *pg;
    struct ceph_pg_pool_info *pool;
    int ruleno;
    unsigned int poolid, ps, pps, t, r;

    poolid = le32_to_cpu(pgid.pool);
    ps = le16_to_cpu(pgid.ps);

    pool = __lookup_pg_pool(&osdmap->pg_pools, poolid);
    if (!pool)
        return NULL;

    /* pg_temp? */
    t = ceph_stable_mod(ps, le32_to_cpu(pool->v.pg_num),
                pool->pgp_num_mask);
    pgid.ps = cpu_to_le16(t);
    pg = __lookup_pg_mapping(&osdmap->pg_temp, pgid);
    if (pg) {
        *num = pg->len;
        return pg->osds;
    }

    /* crush */
    ruleno = crush_find_rule(osdmap->crush, pool->v.crush_ruleset,
                 pool->v.type, pool->v.size);
    if (ruleno < 0) {
        pr_err("no crush rule pool %d ruleset %d type %d size %d\n",
               poolid, pool->v.crush_ruleset, pool->v.type,
               pool->v.size);
        return NULL;
    }

    pps = ceph_stable_mod(ps,
                  le32_to_cpu(pool->v.pgp_num),
                  pool->pgp_num_mask);
    pps += poolid;
    r = crush_do_rule(osdmap->crush, ruleno, pps, osds,
              min_t(int, pool->v.size, *num),
              osdmap->osd_weight);
    if (r < 0) {
        pr_err("error %d from crush rule: pool %d ruleset %d type %d"
               " size %d\n", r, poolid, pool->v.crush_ruleset,
               pool->v.type, pool->v.size);
        return NULL;
    }
    *num = r;
    return osds;
}

/*
 * Return acting set for given pgid.
 */
int ceph_calc_pg_acting(struct ceph_osdmap *osdmap, struct ceph_pg pgid,
            int *acting)
{
    int rawosds[CEPH_PG_MAX_SIZE], *osds;
    int i, o, num = CEPH_PG_MAX_SIZE;

    osds = calc_pg_raw(osdmap, pgid, rawosds, &num);
    if (!osds)
        return -1;

    /* primary is first up osd */
    o = 0;
    for (i = 0; i < num; i++)
        if (ceph_osd_is_up(osdmap, osds[i]))
            acting[o++] = osds[i];
    return o;
}

/*
 * Return primary osd for given pgid, or -1 if none.
 */
int ceph_calc_pg_primary(struct ceph_osdmap *osdmap, struct ceph_pg pgid)
{
    int rawosds[CEPH_PG_MAX_SIZE], *osds;
    int i, num = CEPH_PG_MAX_SIZE;

    osds = calc_pg_raw(osdmap, pgid, rawosds, &num);
    if (!osds)
        return -1;

    /* primary is first up osd */
    for (i = 0; i < num; i++)
        if (ceph_osd_is_up(osdmap, osds[i]))
            return osds[i];
    return -1;
}
EXPORT_SYMBOL(ceph_calc_pg_primary);