#define METASLAB_HINTBP_FAVOR 0x0
#define METASLAB_HINTBP_AVOID 0x1
#define METASLAB_GANG_HEADER 0x2
#define METASLAB_HINTBP_FAVOR 0x0
#define METASLAB_HINTBP_AVOID 0x1
#define METASLAB_GANG_HEADER 0x2
extern int metaslab_alloc(spa_t *spa, metaslab_class_t *mc, uint64_t psize,
blkptr_t *bp, int ncopies, uint64_t txg, blkptr_t *hintbp, int flags);
extern void metaslab_free(spa_t *spa, const blkptr_t *bp, uint64_t txg,
boolean_t now);
extern int metaslab_claim(spa_t *spa, const blkptr_t *bp, uint64_t txg);
extern int metaslab_alloc(spa_t *spa, metaslab_class_t *mc, uint64_t psize,
blkptr_t *bp, int ncopies, uint64_t txg, blkptr_t *hintbp, int flags);
extern void metaslab_free(spa_t *spa, const blkptr_t *bp, uint64_t txg,
boolean_t now);
extern int metaslab_claim(spa_t *spa, const blkptr_t *bp, uint64_t txg);