#include "ceph_debug.h"
  
  #include <linux/slab.h>

  #include <asm/div64.h>
  
  #include "super.h"
  #include "osdmap.h"
  #include "crush/hash.h"
  #include "crush/mapper.h"
  #include "decode.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 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
  ", *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
  ", *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
  ", *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
  ", *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 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;
  
  	dout("crush_decode %p to %p len %d
  ", *p, end, (int)(end - *p));
  
  	c = kzalloc(sizeof(*c), GFP_NOFS);
  	if (c == NULL)
  		return ERR_PTR(-ENOMEM);
  
  	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
  ",
  		       (unsigned)magic, (unsigned)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->device_parents = kcalloc(c->max_devices, sizeof(u32), GFP_NOFS);
  	if (c->device_parents == NULL)
  		goto badmem;
  	c->bucket_parents = kcalloc(c->max_buckets, sizeof(u32), GFP_NOFS);
  	if (c->bucket_parents == NULL)
  		goto badmem;
  
  	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
  ",
  		     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
  ",
  		     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
  ", 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
  ",
  			     i, (int)(*p-start), *p, end);
  			c->rules[i] = NULL;
  			continue;
  		}
  
  		dout("crush_decode rule %d off %x %p to %p
  ",
  		     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(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
  ", 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. */
  
  	dout("crush_decode success
  ");
  	return c;
  
  badmem:
  	err = -ENOMEM;
  bad:
  	dout("crush_decode fail %d
  ", 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;

  
  	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
  			return pg;
  	}
  	return NULL;
  }

  /*

   * 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;
  }

  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);
  }

  void __decode_pool(void **p, struct ceph_pg_pool_info *pi)
  {
  	ceph_decode_copy(p, &pi->v, sizeof(pi->v));
  	calc_pg_masks(pi);
  	*p += le32_to_cpu(pi->v.num_snaps) * sizeof(u64);
  	*p += le32_to_cpu(pi->v.num_removed_snap_intervals) * sizeof(u64) * 2;
  }

  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
  ", num);
  	while (num--) {
  		ceph_decode_32_safe(p, end, pool, bad);
  		ceph_decode_32_safe(p, end, len, bad);
  		dout("  pool %d len %d
  ", pool, len);
  		pi = __lookup_pg_pool(&map->pg_pools, pool);
  		if (pi) {
  			kfree(pi->name);
  			pi->name = kmalloc(len + 1, GFP_NOFS);
  			if (pi->name) {
  				memcpy(pi->name, *p, len);
  				pi->name[len] = '\0';
  				dout("  name is %s
  ", pi->name);
  			}
  		}
  		*p += len;
  	}
  	return 0;
  
  bad:
  	return -EINVAL;
  }
  
  /*
   * osd map
   */
  void ceph_osdmap_destroy(struct ceph_osdmap *map)
  {
  	dout("osdmap_destroy %p
  ", 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
  ", *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
  ", 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
  ",
  				   ev, CEPH_PG_POOL_VERSION);

  			kfree(pi);

  			goto bad;
  		}

  		__decode_pool(p, pi);

  		__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
  ", 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);

  		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
  ", *(u64 *)&pgid, len);

  	}
  
  	/* crush */
  	ceph_decode_32_safe(p, end, len, bad);
  	dout("osdmap_decode crush len %d from off 0x%x
  ", 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
  ", *p, end);
  	return map;
  
  bad:
  	dout("osdmap_decode fail
  ");
  	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;
  	struct rb_node *rbp;
  
  	ceph_decode_16_safe(p, end, version, bad);

  	if (version > CEPH_OSDMAP_INC_VERSION) {
  		pr_warning("got unknown v %d > %d of inc osdmap
  ", 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
  ",
  		     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
  ",
  		     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 = map->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
  ",
  				   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);
  		}

  		__decode_pool(p, pi);

  	}

  	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
  ", osd);
  		BUG_ON(osd >= map->max_osd);
  		map->osd_state[osd] |= CEPH_OSD_UP;
  		map->osd_addr[osd] = addr;
  	}
  
  	/* new_down */
  	ceph_decode_32_safe(p, end, len, bad);
  	while (len--) {
  		u32 osd;
  		ceph_decode_32_safe(p, end, osd, bad);
  		(*p)++;  /* clean flag */

  		pr_info("osd%d down
  ", osd);

  		if (osd < map->max_osd)
  			map->osd_state[osd] &= ~CEPH_OSD_UP;
  	}
  
  	/* 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
  ", 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 */
  	rbp = rb_first(&map->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);

  
  		/* remove any? */

  		while (rbp && pgid_cmp(rb_entry(rbp, struct ceph_pg_mapping,
  						node)->pgid, pgid) <= 0) {

  			struct ceph_pg_mapping *cur =
  				rb_entry(rbp, struct ceph_pg_mapping, node);
  			

  			rbp = rb_next(rbp);

  			dout(" removed pg_temp %llx
  ", *(u64 *)&cur->pgid);
  			rb_erase(&cur->node, &map->pg_temp);
  			kfree(cur);

  		}
  
  		if (pglen) {
  			/* insert */
  			ceph_decode_need(p, end, pglen*sizeof(u32), 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
  ", *(u64 *)&pgid,
  			     pglen);

  		}
  	}
  	while (rbp) {

  		struct ceph_pg_mapping *cur =
  			rb_entry(rbp, struct ceph_pg_mapping, node);

  		rbp = rb_next(rbp);

  		dout(" removed pg_temp %llx
  ", *(u64 *)&cur->pgid);
  		rb_erase(&cur->node, &map->pg_temp);
  		kfree(cur);

  	}
  
  	/* ignore the rest */
  	*p = end;
  	return map;
  
  bad:
  	pr_err("corrupt inc osdmap epoch %d off %d (%p of %p-%p)
  ",
  	       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.
   */
  void 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
  ", off, *plen,
  	     osize, su);

  	su_per_object = osize / su;

  	dout("osize %u / su %u = su_per_object %u
  ", osize, su,
  	     su_per_object);
  
  	BUG_ON((su & ~PAGE_MASK) != 0);
  	/* bl = *off / su; */
  	t = off;
  	do_div(t, su);
  	bl = t;
  	dout("off %llu / su %u = bl %u
  ", 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
  ", objsetno, sc, (unsigned)*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
  ", *oxoff, *oxlen);
  }
  
  /*
   * 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 num, num_mask;

  	struct ceph_pg pgid;

  	s32 preferred = (s32)le32_to_cpu(fl->fl_pg_preferred);
  	int poolid = le32_to_cpu(fl->fl_pg_pool);
  	struct ceph_pg_pool_info *pool;

  	unsigned 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));

  	if (preferred >= 0) {

  		ps += preferred;

  		num = le32_to_cpu(pool->v.lpg_num);
  		num_mask = pool->lpg_num_mask;
  	} else {
  		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(preferred);
  	pgid.pool = fl->fl_pg_pool;

  	if (preferred >= 0)

  		dout("calc_object_layout '%s' pgid %d.%xp%d
  ", oid, poolid, ps,
  		     (int)preferred);

  	else

  		dout("calc_object_layout '%s' pgid %d.%x
  ", oid, poolid, ps);

  	ol->ol_pgid = pgid;

  	ol->ol_stripe_unit = fl->fl_object_stripe_unit;

  	return 0;
  }
  
  /*
   * 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 poolid, ps, pps;
  	int preferred;

  
  	/* pg_temp? */

  	pg = __lookup_pg_mapping(&osdmap->pg_temp, pgid);
  	if (pg) {
  		*num = pg->len;
  		return pg->osds;

  	}
  
  	/* crush */

  	poolid = le32_to_cpu(pgid.pool);
  	ps = le16_to_cpu(pgid.ps);
  	preferred = (s16)le16_to_cpu(pgid.preferred);

  	/* don't forcefeed bad device ids to crush */
  	if (preferred >= osdmap->max_osd ||
  	    preferred >= osdmap->crush->max_devices)
  		preferred = -1;

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

  		return NULL;

  	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 type %d size %d
  ",

  		       poolid, pool->v.type, pool->v.size);

  		return NULL;
  	}

  	if (preferred >= 0)
  		pps = ceph_stable_mod(ps,

  				      le32_to_cpu(pool->v.lpgp_num),
  				      pool->lpgp_num_mask);
  	else

  		pps = ceph_stable_mod(ps,

  				      le32_to_cpu(pool->v.pgp_num),
  				      pool->pgp_num_mask);

  	pps += poolid;

  	*num = crush_do_rule(osdmap->crush, ruleno, pps, osds,
  			     min_t(int, pool->v.size, *num),

  			     preferred, osdmap->osd_weight);

  	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;
  }