root/include/linux/ceph/osdmap.h

INCLUDED FROM

DEFINITIONS

1. ceph_can_shift_osds
2. ceph_oid_set_name
3. ceph_oid_copy
4. ceph_osd_exists
5. ceph_osd_is_up
6. ceph_osd_is_down
7. ceph_osdmap_flag
8. ceph_osd_addr
9. ceph_decode_pgid

#ifndef _FS_CEPH_OSDMAP_H
#define _FS_CEPH_OSDMAP_H

#include <linux/rbtree.h>
#include <linux/ceph/types.h>
#include <linux/ceph/decode.h>
#include <linux/ceph/ceph_fs.h>
#include <linux/crush/crush.h>

/*
 * The osd map describes the current membership of the osd cluster and
 * specifies the mapping of objects to placement groups and placement
 * groups to (sets of) osds.  That is, it completely specifies the
 * (desired) distribution of all data objects in the system at some
 * point in time.
 *
 * Each map version is identified by an epoch, which increases monotonically.
 *
 * The map can be updated either via an incremental map (diff) describing
 * the change between two successive epochs, or as a fully encoded map.
 */
struct ceph_pg {
        uint64_t pool;
        uint32_t seed;
};

#define CEPH_POOL_FLAG_HASHPSPOOL  1

struct ceph_pg_pool_info {
        struct rb_node node;
        s64 id;
        u8 type;
        u8 size;
        u8 crush_ruleset;
        u8 object_hash;
        u32 pg_num, pgp_num;
        int pg_num_mask, pgp_num_mask;
        s64 read_tier;
        s64 write_tier; /* wins for read+write ops */
        u64 flags;
        char *name;
};

static inline bool ceph_can_shift_osds(struct ceph_pg_pool_info *pool)
{
        switch (pool->type) {
        case CEPH_POOL_TYPE_REP:
                return true;
        case CEPH_POOL_TYPE_EC:
                return false;
        default:
                BUG_ON(1);
        }
}

struct ceph_object_locator {
        s64 pool;
};

/*
 * Maximum supported by kernel client object name length
 *
 * (probably outdated: must be >= RBD_MAX_MD_NAME_LEN -- currently 100)
 */
#define CEPH_MAX_OID_NAME_LEN 100

struct ceph_object_id {
        char name[CEPH_MAX_OID_NAME_LEN];
        int name_len;
};

struct ceph_pg_mapping {
        struct rb_node node;
        struct ceph_pg pgid;

        union {
                struct {
                        int len;
                        int osds[];
                } pg_temp;
                struct {
                        int osd;
                } primary_temp;
        };
};

struct ceph_osdmap {
        struct ceph_fsid fsid;
        u32 epoch;
        u32 mkfs_epoch;
        struct ceph_timespec created, modified;

        u32 flags;         /* CEPH_OSDMAP_* */

        u32 max_osd;       /* size of osd_state, _offload, _addr arrays */
        u8 *osd_state;     /* CEPH_OSD_* */
        u32 *osd_weight;   /* 0 = failed, 0x10000 = 100% normal */
        struct ceph_entity_addr *osd_addr;

        struct rb_root pg_temp;
        struct rb_root primary_temp;

        u32 *osd_primary_affinity;

        struct rb_root pg_pools;
        u32 pool_max;

        /* the CRUSH map specifies the mapping of placement groups to
         * the list of osds that store+replicate them. */
        struct crush_map *crush;

        struct mutex crush_scratch_mutex;
        int crush_scratch_ary[CEPH_PG_MAX_SIZE * 3];
};

static inline void ceph_oid_set_name(struct ceph_object_id *oid,
                                     const char *name)
{
        int len;

        len = strlen(name);
        if (len > sizeof(oid->name)) {
                WARN(1, "ceph_oid_set_name '%s' len %d vs %zu, truncating\n",
                     name, len, sizeof(oid->name));
                len = sizeof(oid->name);
        }

        memcpy(oid->name, name, len);
        oid->name_len = len;
}

static inline void ceph_oid_copy(struct ceph_object_id *dest,
                                 struct ceph_object_id *src)
{
        BUG_ON(src->name_len > sizeof(dest->name));
        memcpy(dest->name, src->name, src->name_len);
        dest->name_len = src->name_len;
}

static inline int ceph_osd_exists(struct ceph_osdmap *map, int osd)
{
        return osd >= 0 && osd < map->max_osd &&
               (map->osd_state[osd] & CEPH_OSD_EXISTS);
}

static inline int ceph_osd_is_up(struct ceph_osdmap *map, int osd)
{
        return ceph_osd_exists(map, osd) &&
               (map->osd_state[osd] & CEPH_OSD_UP);
}

static inline int ceph_osd_is_down(struct ceph_osdmap *map, int osd)
{
        return !ceph_osd_is_up(map, osd);
}

static inline bool ceph_osdmap_flag(struct ceph_osdmap *map, int flag)
{
        return map && (map->flags & flag);
}

extern char *ceph_osdmap_state_str(char *str, int len, int state);
extern u32 ceph_get_primary_affinity(struct ceph_osdmap *map, int osd);

static inline struct ceph_entity_addr *ceph_osd_addr(struct ceph_osdmap *map,
                                                     int osd)
{
        if (osd >= map->max_osd)
                return NULL;
        return &map->osd_addr[osd];
}

static inline int ceph_decode_pgid(void **p, void *end, struct ceph_pg *pgid)
{
        __u8 version;

        if (!ceph_has_room(p, end, 1 + 8 + 4 + 4)) {
                pr_warning("incomplete pg encoding");

                return -EINVAL;
        }
        version = ceph_decode_8(p);
        if (version > 1) {
                pr_warning("do not understand pg encoding %d > 1",
                        (int)version);
                return -EINVAL;
        }

        pgid->pool = ceph_decode_64(p);
        pgid->seed = ceph_decode_32(p);
        *p += 4;        /* skip deprecated preferred value */

        return 0;
}

extern struct ceph_osdmap *ceph_osdmap_decode(void **p, void *end);
extern struct ceph_osdmap *osdmap_apply_incremental(void **p, void *end,
                                            struct ceph_osdmap *map,
                                            struct ceph_messenger *msgr);
extern void ceph_osdmap_destroy(struct ceph_osdmap *map);

/* calculate mapping of a file extent to an object */
extern int ceph_calc_file_object_mapping(struct ceph_file_layout *layout,
                                         u64 off, u64 len,
                                         u64 *bno, u64 *oxoff, u64 *oxlen);

/* calculate mapping of object to a placement group */
extern int ceph_oloc_oid_to_pg(struct ceph_osdmap *osdmap,
                               struct ceph_object_locator *oloc,
                               struct ceph_object_id *oid,
                               struct ceph_pg *pg_out);

extern int ceph_calc_pg_acting(struct ceph_osdmap *osdmap,
                               struct ceph_pg pgid,
                               int *osds, int *primary);
extern int ceph_calc_pg_primary(struct ceph_osdmap *osdmap,
                                struct ceph_pg pgid);

extern struct ceph_pg_pool_info *ceph_pg_pool_by_id(struct ceph_osdmap *map,
                                                    u64 id);

extern const char *ceph_pg_pool_name_by_id(struct ceph_osdmap *map, u64 id);
extern int ceph_pg_poolid_by_name(struct ceph_osdmap *map, const char *name);

#endif