Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / net / ceph / osdmap.c
diff --git a/kernel/net/ceph/osdmap.c b/kernel/net/ceph/osdmap.c
new file mode 100644 (file)
index 0000000..1579669
--- /dev/null
@@ -0,0 +1,1754 @@
+
+#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)
+{
+       if (!len)
+               return str;
+
+       if ((state & CEPH_OSD_EXISTS) && (state & CEPH_OSD_UP))
+               snprintf(str, len, "exists, up");
+       else if (state & CEPH_OSD_EXISTS)
+               snprintf(str, len, "exists");
+       else if (state & CEPH_OSD_UP)
+               snprintf(str, len, "up");
+       else
+               snprintf(str, len, "doesn't exist");
+
+       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(pi->pg_num-1)) - 1;
+       pi->pgp_num_mask = (1 << calc_bits_of(pi->pgp_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 crush_decode_straw2_bucket(void **p, void *end,
+                                     struct crush_bucket_straw2 *b)
+{
+       int j;
+       dout("crush_decode_straw2_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;
+       ceph_decode_need(p, end, b->h.size * sizeof(u32), bad);
+       for (j = 0; j < b->h.size; j++)
+               b->item_weights[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;
+       c->chooseleaf_descend_once = 0;
+
+       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;
+               case CRUSH_BUCKET_STRAW2:
+                       size = sizeof(struct crush_bucket_straw2);
+                       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;
+               case CRUSH_BUCKET_STRAW2:
+                       err = crush_decode_straw2_bucket(p, end,
+                               (struct crush_bucket_straw2 *)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);
+
+       ceph_decode_need(p, end, sizeof(u32), done);
+       c->chooseleaf_descend_once = ceph_decode_32(p);
+       dout("crush decode tunable chooseleaf_descend_once = %d",
+            c->chooseleaf_descend_once);
+
+       ceph_decode_need(p, end, sizeof(u8), done);
+       c->chooseleaf_vary_r = ceph_decode_8(p);
+       dout("crush decode tunable chooseleaf_vary_r = %d",
+            c->chooseleaf_vary_r);
+
+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) and primary_temp (explicit primary setting)
+ */
+static int pgid_cmp(struct ceph_pg l, struct ceph_pg r)
+{
+       if (l.pool < r.pool)
+               return -1;
+       if (l.pool > r.pool)
+               return 1;
+       if (l.seed < r.seed)
+               return -1;
+       if (l.seed > r.seed)
+               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 %lld.%x got %p\n",
+                            pgid.pool, pgid.seed, 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 %lld.%x %p\n", pgid.pool, pgid.seed,
+                    pg);
+               rb_erase(&pg->node, root);
+               kfree(pg);
+               return 0;
+       }
+       dout("__remove_pg_mapping %lld.%x dne\n", pgid.pool, pgid.seed);
+       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, u64 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;
+}
+
+struct ceph_pg_pool_info *ceph_pg_pool_by_id(struct ceph_osdmap *map, u64 id)
+{
+       return __lookup_pg_pool(&map->pg_pools, id);
+}
+
+const char *ceph_pg_pool_name_by_id(struct ceph_osdmap *map, u64 id)
+{
+       struct ceph_pg_pool_info *pi;
+
+       if (id == CEPH_NOPOOL)
+               return NULL;
+
+       if (WARN_ON_ONCE(id > (u64) INT_MAX))
+               return NULL;
+
+       pi = __lookup_pg_pool(&map->pg_pools, (int) id);
+
+       return pi ? pi->name : NULL;
+}
+EXPORT_SYMBOL(ceph_pg_pool_name_by_id);
+
+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)
+{
+       u8 ev, cv;
+       unsigned len, num;
+       void *pool_end;
+
+       ceph_decode_need(p, end, 2 + 4, bad);
+       ev = ceph_decode_8(p);  /* encoding version */
+       cv = ceph_decode_8(p); /* compat version */
+       if (ev < 5) {
+               pr_warn("got v %d < 5 cv %d of ceph_pg_pool\n", ev, cv);
+               return -EINVAL;
+       }
+       if (cv > 9) {
+               pr_warn("got v %d cv %d > 9 of ceph_pg_pool\n", ev, cv);
+               return -EINVAL;
+       }
+       len = ceph_decode_32(p);
+       ceph_decode_need(p, end, len, bad);
+       pool_end = *p + len;
+
+       pi->type = ceph_decode_8(p);
+       pi->size = ceph_decode_8(p);
+       pi->crush_ruleset = ceph_decode_8(p);
+       pi->object_hash = ceph_decode_8(p);
+
+       pi->pg_num = ceph_decode_32(p);
+       pi->pgp_num = ceph_decode_32(p);
+
+       *p += 4 + 4;  /* skip lpg* */
+       *p += 4;      /* skip last_change */
+       *p += 8 + 4;  /* skip snap_seq, snap_epoch */
+
+       /* skip snaps */
+       num = ceph_decode_32(p);
+       while (num--) {
+               *p += 8;  /* snapid key */
+               *p += 1 + 1; /* versions */
+               len = ceph_decode_32(p);
+               *p += len;
+       }
+
+       /* skip removed_snaps */
+       num = ceph_decode_32(p);
+       *p += num * (8 + 8);
+
+       *p += 8;  /* skip auid */
+       pi->flags = ceph_decode_64(p);
+       *p += 4;  /* skip crash_replay_interval */
+
+       if (ev >= 7)
+               *p += 1;  /* skip min_size */
+
+       if (ev >= 8)
+               *p += 8 + 8;  /* skip quota_max_* */
+
+       if (ev >= 9) {
+               /* skip tiers */
+               num = ceph_decode_32(p);
+               *p += num * 8;
+
+               *p += 8;  /* skip tier_of */
+               *p += 1;  /* skip cache_mode */
+
+               pi->read_tier = ceph_decode_64(p);
+               pi->write_tier = ceph_decode_64(p);
+       } else {
+               pi->read_tier = -1;
+               pi->write_tier = -1;
+       }
+
+       /* ignore the rest */
+
+       *p = pool_end;
+       calc_pg_masks(pi);
+       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;
+       u64 pool;
+
+       ceph_decode_32_safe(p, end, num, bad);
+       dout(" %d pool names\n", num);
+       while (num--) {
+               ceph_decode_64_safe(p, end, pool, bad);
+               ceph_decode_32_safe(p, end, len, bad);
+               dout("  pool %llu 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->primary_temp)) {
+               struct ceph_pg_mapping *pg =
+                       rb_entry(rb_first(&map->primary_temp),
+                                struct ceph_pg_mapping, node);
+               rb_erase(&pg->node, &map->primary_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->osd_primary_affinity);
+       kfree(map);
+}
+
+/*
+ * Adjust max_osd value, (re)allocate arrays.
+ *
+ * The new elements are properly initialized.
+ */
+static int osdmap_set_max_osd(struct ceph_osdmap *map, int max)
+{
+       u8 *state;
+       u32 *weight;
+       struct ceph_entity_addr *addr;
+       int i;
+
+       state = krealloc(map->osd_state, max*sizeof(*state), GFP_NOFS);
+       if (!state)
+               return -ENOMEM;
+       map->osd_state = state;
+
+       weight = krealloc(map->osd_weight, max*sizeof(*weight), GFP_NOFS);
+       if (!weight)
+               return -ENOMEM;
+       map->osd_weight = weight;
+
+       addr = krealloc(map->osd_addr, max*sizeof(*addr), GFP_NOFS);
+       if (!addr)
+               return -ENOMEM;
+       map->osd_addr = addr;
+
+       for (i = map->max_osd; i < max; i++) {
+               map->osd_state[i] = 0;
+               map->osd_weight[i] = CEPH_OSD_OUT;
+               memset(map->osd_addr + i, 0, sizeof(*map->osd_addr));
+       }
+
+       if (map->osd_primary_affinity) {
+               u32 *affinity;
+
+               affinity = krealloc(map->osd_primary_affinity,
+                                   max*sizeof(*affinity), GFP_NOFS);
+               if (!affinity)
+                       return -ENOMEM;
+               map->osd_primary_affinity = affinity;
+
+               for (i = map->max_osd; i < max; i++)
+                       map->osd_primary_affinity[i] =
+                           CEPH_OSD_DEFAULT_PRIMARY_AFFINITY;
+       }
+
+       map->max_osd = max;
+
+       return 0;
+}
+
+#define OSDMAP_WRAPPER_COMPAT_VER      7
+#define OSDMAP_CLIENT_DATA_COMPAT_VER  1
+
+/*
+ * Return 0 or error.  On success, *v is set to 0 for old (v6) osdmaps,
+ * to struct_v of the client_data section for new (v7 and above)
+ * osdmaps.
+ */
+static int get_osdmap_client_data_v(void **p, void *end,
+                                   const char *prefix, u8 *v)
+{
+       u8 struct_v;
+
+       ceph_decode_8_safe(p, end, struct_v, e_inval);
+       if (struct_v >= 7) {
+               u8 struct_compat;
+
+               ceph_decode_8_safe(p, end, struct_compat, e_inval);
+               if (struct_compat > OSDMAP_WRAPPER_COMPAT_VER) {
+                       pr_warn("got v %d cv %d > %d of %s ceph_osdmap\n",
+                               struct_v, struct_compat,
+                               OSDMAP_WRAPPER_COMPAT_VER, prefix);
+                       return -EINVAL;
+               }
+               *p += 4; /* ignore wrapper struct_len */
+
+               ceph_decode_8_safe(p, end, struct_v, e_inval);
+               ceph_decode_8_safe(p, end, struct_compat, e_inval);
+               if (struct_compat > OSDMAP_CLIENT_DATA_COMPAT_VER) {
+                       pr_warn("got v %d cv %d > %d of %s ceph_osdmap client data\n",
+                               struct_v, struct_compat,
+                               OSDMAP_CLIENT_DATA_COMPAT_VER, prefix);
+                       return -EINVAL;
+               }
+               *p += 4; /* ignore client data struct_len */
+       } else {
+               u16 version;
+
+               *p -= 1;
+               ceph_decode_16_safe(p, end, version, e_inval);
+               if (version < 6) {
+                       pr_warn("got v %d < 6 of %s ceph_osdmap\n",
+                               version, prefix);
+                       return -EINVAL;
+               }
+
+               /* old osdmap enconding */
+               struct_v = 0;
+       }
+
+       *v = struct_v;
+       return 0;
+
+e_inval:
+       return -EINVAL;
+}
+
+static int __decode_pools(void **p, void *end, struct ceph_osdmap *map,
+                         bool incremental)
+{
+       u32 n;
+
+       ceph_decode_32_safe(p, end, n, e_inval);
+       while (n--) {
+               struct ceph_pg_pool_info *pi;
+               u64 pool;
+               int ret;
+
+               ceph_decode_64_safe(p, end, pool, e_inval);
+
+               pi = __lookup_pg_pool(&map->pg_pools, pool);
+               if (!incremental || !pi) {
+                       pi = kzalloc(sizeof(*pi), GFP_NOFS);
+                       if (!pi)
+                               return -ENOMEM;
+
+                       pi->id = pool;
+
+                       ret = __insert_pg_pool(&map->pg_pools, pi);
+                       if (ret) {
+                               kfree(pi);
+                               return ret;
+                       }
+               }
+
+               ret = decode_pool(p, end, pi);
+               if (ret)
+                       return ret;
+       }
+
+       return 0;
+
+e_inval:
+       return -EINVAL;
+}
+
+static int decode_pools(void **p, void *end, struct ceph_osdmap *map)
+{
+       return __decode_pools(p, end, map, false);
+}
+
+static int decode_new_pools(void **p, void *end, struct ceph_osdmap *map)
+{
+       return __decode_pools(p, end, map, true);
+}
+
+static int __decode_pg_temp(void **p, void *end, struct ceph_osdmap *map,
+                           bool incremental)
+{
+       u32 n;
+
+       ceph_decode_32_safe(p, end, n, e_inval);
+       while (n--) {
+               struct ceph_pg pgid;
+               u32 len, i;
+               int ret;
+
+               ret = ceph_decode_pgid(p, end, &pgid);
+               if (ret)
+                       return ret;
+
+               ceph_decode_32_safe(p, end, len, e_inval);
+
+               ret = __remove_pg_mapping(&map->pg_temp, pgid);
+               BUG_ON(!incremental && ret != -ENOENT);
+
+               if (!incremental || len > 0) {
+                       struct ceph_pg_mapping *pg;
+
+                       ceph_decode_need(p, end, len*sizeof(u32), e_inval);
+
+                       if (len > (UINT_MAX - sizeof(*pg)) / sizeof(u32))
+                               return -EINVAL;
+
+                       pg = kzalloc(sizeof(*pg) + len*sizeof(u32), GFP_NOFS);
+                       if (!pg)
+                               return -ENOMEM;
+
+                       pg->pgid = pgid;
+                       pg->pg_temp.len = len;
+                       for (i = 0; i < len; i++)
+                               pg->pg_temp.osds[i] = ceph_decode_32(p);
+
+                       ret = __insert_pg_mapping(pg, &map->pg_temp);
+                       if (ret) {
+                               kfree(pg);
+                               return ret;
+                       }
+               }
+       }
+
+       return 0;
+
+e_inval:
+       return -EINVAL;
+}
+
+static int decode_pg_temp(void **p, void *end, struct ceph_osdmap *map)
+{
+       return __decode_pg_temp(p, end, map, false);
+}
+
+static int decode_new_pg_temp(void **p, void *end, struct ceph_osdmap *map)
+{
+       return __decode_pg_temp(p, end, map, true);
+}
+
+static int __decode_primary_temp(void **p, void *end, struct ceph_osdmap *map,
+                                bool incremental)
+{
+       u32 n;
+
+       ceph_decode_32_safe(p, end, n, e_inval);
+       while (n--) {
+               struct ceph_pg pgid;
+               u32 osd;
+               int ret;
+
+               ret = ceph_decode_pgid(p, end, &pgid);
+               if (ret)
+                       return ret;
+
+               ceph_decode_32_safe(p, end, osd, e_inval);
+
+               ret = __remove_pg_mapping(&map->primary_temp, pgid);
+               BUG_ON(!incremental && ret != -ENOENT);
+
+               if (!incremental || osd != (u32)-1) {
+                       struct ceph_pg_mapping *pg;
+
+                       pg = kzalloc(sizeof(*pg), GFP_NOFS);
+                       if (!pg)
+                               return -ENOMEM;
+
+                       pg->pgid = pgid;
+                       pg->primary_temp.osd = osd;
+
+                       ret = __insert_pg_mapping(pg, &map->primary_temp);
+                       if (ret) {
+                               kfree(pg);
+                               return ret;
+                       }
+               }
+       }
+
+       return 0;
+
+e_inval:
+       return -EINVAL;
+}
+
+static int decode_primary_temp(void **p, void *end, struct ceph_osdmap *map)
+{
+       return __decode_primary_temp(p, end, map, false);
+}
+
+static int decode_new_primary_temp(void **p, void *end,
+                                  struct ceph_osdmap *map)
+{
+       return __decode_primary_temp(p, end, map, true);
+}
+
+u32 ceph_get_primary_affinity(struct ceph_osdmap *map, int osd)
+{
+       BUG_ON(osd >= map->max_osd);
+
+       if (!map->osd_primary_affinity)
+               return CEPH_OSD_DEFAULT_PRIMARY_AFFINITY;
+
+       return map->osd_primary_affinity[osd];
+}
+
+static int set_primary_affinity(struct ceph_osdmap *map, int osd, u32 aff)
+{
+       BUG_ON(osd >= map->max_osd);
+
+       if (!map->osd_primary_affinity) {
+               int i;
+
+               map->osd_primary_affinity = kmalloc(map->max_osd*sizeof(u32),
+                                                   GFP_NOFS);
+               if (!map->osd_primary_affinity)
+                       return -ENOMEM;
+
+               for (i = 0; i < map->max_osd; i++)
+                       map->osd_primary_affinity[i] =
+                           CEPH_OSD_DEFAULT_PRIMARY_AFFINITY;
+       }
+
+       map->osd_primary_affinity[osd] = aff;
+
+       return 0;
+}
+
+static int decode_primary_affinity(void **p, void *end,
+                                  struct ceph_osdmap *map)
+{
+       u32 len, i;
+
+       ceph_decode_32_safe(p, end, len, e_inval);
+       if (len == 0) {
+               kfree(map->osd_primary_affinity);
+               map->osd_primary_affinity = NULL;
+               return 0;
+       }
+       if (len != map->max_osd)
+               goto e_inval;
+
+       ceph_decode_need(p, end, map->max_osd*sizeof(u32), e_inval);
+
+       for (i = 0; i < map->max_osd; i++) {
+               int ret;
+
+               ret = set_primary_affinity(map, i, ceph_decode_32(p));
+               if (ret)
+                       return ret;
+       }
+
+       return 0;
+
+e_inval:
+       return -EINVAL;
+}
+
+static int decode_new_primary_affinity(void **p, void *end,
+                                      struct ceph_osdmap *map)
+{
+       u32 n;
+
+       ceph_decode_32_safe(p, end, n, e_inval);
+       while (n--) {
+               u32 osd, aff;
+               int ret;
+
+               ceph_decode_32_safe(p, end, osd, e_inval);
+               ceph_decode_32_safe(p, end, aff, e_inval);
+
+               ret = set_primary_affinity(map, osd, aff);
+               if (ret)
+                       return ret;
+
+               pr_info("osd%d primary-affinity 0x%x\n", osd, aff);
+       }
+
+       return 0;
+
+e_inval:
+       return -EINVAL;
+}
+
+/*
+ * decode a full map.
+ */
+static int osdmap_decode(void **p, void *end, struct ceph_osdmap *map)
+{
+       u8 struct_v;
+       u32 epoch = 0;
+       void *start = *p;
+       u32 max;
+       u32 len, i;
+       int err;
+
+       dout("%s %p to %p len %d\n", __func__, *p, end, (int)(end - *p));
+
+       err = get_osdmap_client_data_v(p, end, "full", &struct_v);
+       if (err)
+               goto bad;
+
+       /* fsid, epoch, created, modified */
+       ceph_decode_need(p, end, sizeof(map->fsid) + sizeof(u32) +
+                        sizeof(map->created) + sizeof(map->modified), e_inval);
+       ceph_decode_copy(p, &map->fsid, sizeof(map->fsid));
+       epoch = map->epoch = ceph_decode_32(p);
+       ceph_decode_copy(p, &map->created, sizeof(map->created));
+       ceph_decode_copy(p, &map->modified, sizeof(map->modified));
+
+       /* pools */
+       err = decode_pools(p, end, map);
+       if (err)
+               goto bad;
+
+       /* pool_name */
+       err = decode_pool_names(p, end, map);
+       if (err)
+               goto bad;
+
+       ceph_decode_32_safe(p, end, map->pool_max, e_inval);
+
+       ceph_decode_32_safe(p, end, map->flags, e_inval);
+
+       /* max_osd */
+       ceph_decode_32_safe(p, end, max, e_inval);
+
+       /* (re)alloc osd arrays */
+       err = osdmap_set_max_osd(map, max);
+       if (err)
+               goto bad;
+
+       /* osd_state, osd_weight, osd_addrs->client_addr */
+       ceph_decode_need(p, end, 3*sizeof(u32) +
+                        map->max_osd*(1 + sizeof(*map->osd_weight) +
+                                      sizeof(*map->osd_addr)), e_inval);
+
+       if (ceph_decode_32(p) != map->max_osd)
+               goto e_inval;
+
+       ceph_decode_copy(p, map->osd_state, map->max_osd);
+
+       if (ceph_decode_32(p) != map->max_osd)
+               goto e_inval;
+
+       for (i = 0; i < map->max_osd; i++)
+               map->osd_weight[i] = ceph_decode_32(p);
+
+       if (ceph_decode_32(p) != map->max_osd)
+               goto e_inval;
+
+       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 */
+       err = decode_pg_temp(p, end, map);
+       if (err)
+               goto bad;
+
+       /* primary_temp */
+       if (struct_v >= 1) {
+               err = decode_primary_temp(p, end, map);
+               if (err)
+                       goto bad;
+       }
+
+       /* primary_affinity */
+       if (struct_v >= 2) {
+               err = decode_primary_affinity(p, end, map);
+               if (err)
+                       goto bad;
+       } else {
+               /* XXX can this happen? */
+               kfree(map->osd_primary_affinity);
+               map->osd_primary_affinity = NULL;
+       }
+
+       /* crush */
+       ceph_decode_32_safe(p, end, len, e_inval);
+       map->crush = crush_decode(*p, min(*p + len, end));
+       if (IS_ERR(map->crush)) {
+               err = PTR_ERR(map->crush);
+               map->crush = NULL;
+               goto bad;
+       }
+       *p += len;
+
+       /* ignore the rest */
+       *p = end;
+
+       dout("full osdmap epoch %d max_osd %d\n", map->epoch, map->max_osd);
+       return 0;
+
+e_inval:
+       err = -EINVAL;
+bad:
+       pr_err("corrupt full osdmap (%d) epoch %d off %d (%p of %p-%p)\n",
+              err, epoch, (int)(*p - start), *p, start, end);
+       print_hex_dump(KERN_DEBUG, "osdmap: ",
+                      DUMP_PREFIX_OFFSET, 16, 1,
+                      start, end - start, true);
+       return err;
+}
+
+/*
+ * Allocate and decode a full map.
+ */
+struct ceph_osdmap *ceph_osdmap_decode(void **p, void *end)
+{
+       struct ceph_osdmap *map;
+       int ret;
+
+       map = kzalloc(sizeof(*map), GFP_NOFS);
+       if (!map)
+               return ERR_PTR(-ENOMEM);
+
+       map->pg_temp = RB_ROOT;
+       map->primary_temp = RB_ROOT;
+       mutex_init(&map->crush_scratch_mutex);
+
+       ret = osdmap_decode(p, end, map);
+       if (ret) {
+               ceph_osdmap_destroy(map);
+               return ERR_PTR(ret);
+       }
+
+       return map;
+}
+
+/*
+ * 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;
+       s32 len;
+       u64 pool;
+       __s64 new_pool_max;
+       __s32 new_flags, max;
+       void *start = *p;
+       int err;
+       u8 struct_v;
+
+       dout("%s %p to %p len %d\n", __func__, *p, end, (int)(end - *p));
+
+       err = get_osdmap_client_data_v(p, end, "inc", &struct_v);
+       if (err)
+               goto bad;
+
+       /* fsid, epoch, modified, new_pool_max, new_flags */
+       ceph_decode_need(p, end, sizeof(fsid) + sizeof(u32) + sizeof(modified) +
+                        sizeof(u64) + sizeof(u32), e_inval);
+       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_64(p);
+       new_flags = ceph_decode_32(p);
+
+       /* full map? */
+       ceph_decode_32_safe(p, end, len, e_inval);
+       if (len > 0) {
+               dout("apply_incremental full map len %d, %p to %p\n",
+                    len, *p, end);
+               return ceph_osdmap_decode(p, min(*p+len, end));
+       }
+
+       /* new crush? */
+       ceph_decode_32_safe(p, end, len, e_inval);
+       if (len > 0) {
+               newcrush = crush_decode(*p, min(*p+len, end));
+               if (IS_ERR(newcrush)) {
+                       err = PTR_ERR(newcrush);
+                       newcrush = NULL;
+                       goto bad;
+               }
+               *p += len;
+       }
+
+       /* new flags? */
+       if (new_flags >= 0)
+               map->flags = new_flags;
+       if (new_pool_max >= 0)
+               map->pool_max = new_pool_max;
+
+       /* new max? */
+       ceph_decode_32_safe(p, end, max, e_inval);
+       if (max >= 0) {
+               err = osdmap_set_max_osd(map, max);
+               if (err)
+                       goto bad;
+       }
+
+       map->epoch++;
+       map->modified = modified;
+       if (newcrush) {
+               if (map->crush)
+                       crush_destroy(map->crush);
+               map->crush = newcrush;
+               newcrush = NULL;
+       }
+
+       /* new_pools */
+       err = decode_new_pools(p, end, map);
+       if (err)
+               goto bad;
+
+       /* new_pool_names */
+       err = decode_pool_names(p, end, map);
+       if (err)
+               goto bad;
+
+       /* old_pool */
+       ceph_decode_32_safe(p, end, len, e_inval);
+       while (len--) {
+               struct ceph_pg_pool_info *pi;
+
+               ceph_decode_64_safe(p, end, pool, e_inval);
+               pi = __lookup_pg_pool(&map->pg_pools, pool);
+               if (pi)
+                       __remove_pg_pool(&map->pg_pools, pi);
+       }
+
+       /* new_up */
+       ceph_decode_32_safe(p, end, len, e_inval);
+       while (len--) {
+               u32 osd;
+               struct ceph_entity_addr addr;
+               ceph_decode_32_safe(p, end, osd, e_inval);
+               ceph_decode_copy_safe(p, end, &addr, sizeof(addr), e_inval);
+               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, e_inval);
+       while (len--) {
+               u32 osd;
+               u8 xorstate;
+               ceph_decode_32_safe(p, end, osd, e_inval);
+               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, e_inval);
+       while (len--) {
+               u32 osd, off;
+               ceph_decode_need(p, end, sizeof(u32)*2, e_inval);
+               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 */
+       err = decode_new_pg_temp(p, end, map);
+       if (err)
+               goto bad;
+
+       /* new_primary_temp */
+       if (struct_v >= 1) {
+               err = decode_new_primary_temp(p, end, map);
+               if (err)
+                       goto bad;
+       }
+
+       /* new_primary_affinity */
+       if (struct_v >= 2) {
+               err = decode_new_primary_affinity(p, end, map);
+               if (err)
+                       goto bad;
+       }
+
+       /* ignore the rest */
+       *p = end;
+
+       dout("inc osdmap epoch %d max_osd %d\n", map->epoch, map->max_osd);
+       return map;
+
+e_inval:
+       err = -EINVAL;
+bad:
+       pr_err("corrupt inc osdmap (%d) epoch %d off %d (%p of %p-%p)\n",
+              err, 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 len,
+                                  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, len,
+            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 (len) or
+        * the remainder of the current stripe being written to.
+        */
+       *oxlen = min_t(u64, len, su - su_offset);
+
+       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 mapping of a (oloc, oid) pair to a PG.  Should only be
+ * called with target's (oloc, oid), since tiering isn't taken into
+ * account.
+ */
+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)
+{
+       struct ceph_pg_pool_info *pi;
+
+       pi = __lookup_pg_pool(&osdmap->pg_pools, oloc->pool);
+       if (!pi)
+               return -EIO;
+
+       pg_out->pool = oloc->pool;
+       pg_out->seed = ceph_str_hash(pi->object_hash, oid->name,
+                                    oid->name_len);
+
+       dout("%s '%.*s' pgid %llu.%x\n", __func__, oid->name_len, oid->name,
+            pg_out->pool, pg_out->seed);
+       return 0;
+}
+EXPORT_SYMBOL(ceph_oloc_oid_to_pg);
+
+static int do_crush(struct ceph_osdmap *map, int ruleno, int x,
+                   int *result, int result_max,
+                   const __u32 *weight, int weight_max)
+{
+       int r;
+
+       BUG_ON(result_max > CEPH_PG_MAX_SIZE);
+
+       mutex_lock(&map->crush_scratch_mutex);
+       r = crush_do_rule(map->crush, ruleno, x, result, result_max,
+                         weight, weight_max, map->crush_scratch_ary);
+       mutex_unlock(&map->crush_scratch_mutex);
+
+       return r;
+}
+
+/*
+ * Calculate raw (crush) set for given pgid.
+ *
+ * Return raw set length, or error.
+ */
+static int pg_to_raw_osds(struct ceph_osdmap *osdmap,
+                         struct ceph_pg_pool_info *pool,
+                         struct ceph_pg pgid, u32 pps, int *osds)
+{
+       int ruleno;
+       int len;
+
+       /* crush */
+       ruleno = crush_find_rule(osdmap->crush, pool->crush_ruleset,
+                                pool->type, pool->size);
+       if (ruleno < 0) {
+               pr_err("no crush rule: pool %lld ruleset %d type %d size %d\n",
+                      pgid.pool, pool->crush_ruleset, pool->type,
+                      pool->size);
+               return -ENOENT;
+       }
+
+       len = do_crush(osdmap, ruleno, pps, osds,
+                      min_t(int, pool->size, CEPH_PG_MAX_SIZE),
+                      osdmap->osd_weight, osdmap->max_osd);
+       if (len < 0) {
+               pr_err("error %d from crush rule %d: pool %lld ruleset %d type %d size %d\n",
+                      len, ruleno, pgid.pool, pool->crush_ruleset,
+                      pool->type, pool->size);
+               return len;
+       }
+
+       return len;
+}
+
+/*
+ * Given raw set, calculate up set and up primary.
+ *
+ * Return up set length.  *primary is set to up primary osd id, or -1
+ * if up set is empty.
+ */
+static int raw_to_up_osds(struct ceph_osdmap *osdmap,
+                         struct ceph_pg_pool_info *pool,
+                         int *osds, int len, int *primary)
+{
+       int up_primary = -1;
+       int i;
+
+       if (ceph_can_shift_osds(pool)) {
+               int removed = 0;
+
+               for (i = 0; i < len; i++) {
+                       if (ceph_osd_is_down(osdmap, osds[i])) {
+                               removed++;
+                               continue;
+                       }
+                       if (removed)
+                               osds[i - removed] = osds[i];
+               }
+
+               len -= removed;
+               if (len > 0)
+                       up_primary = osds[0];
+       } else {
+               for (i = len - 1; i >= 0; i--) {
+                       if (ceph_osd_is_down(osdmap, osds[i]))
+                               osds[i] = CRUSH_ITEM_NONE;
+                       else
+                               up_primary = osds[i];
+               }
+       }
+
+       *primary = up_primary;
+       return len;
+}
+
+static void apply_primary_affinity(struct ceph_osdmap *osdmap, u32 pps,
+                                  struct ceph_pg_pool_info *pool,
+                                  int *osds, int len, int *primary)
+{
+       int i;
+       int pos = -1;
+
+       /*
+        * Do we have any non-default primary_affinity values for these
+        * osds?
+        */
+       if (!osdmap->osd_primary_affinity)
+               return;
+
+       for (i = 0; i < len; i++) {
+               int osd = osds[i];
+
+               if (osd != CRUSH_ITEM_NONE &&
+                   osdmap->osd_primary_affinity[osd] !=
+                                       CEPH_OSD_DEFAULT_PRIMARY_AFFINITY) {
+                       break;
+               }
+       }
+       if (i == len)
+               return;
+
+       /*
+        * Pick the primary.  Feed both the seed (for the pg) and the
+        * osd into the hash/rng so that a proportional fraction of an
+        * osd's pgs get rejected as primary.
+        */
+       for (i = 0; i < len; i++) {
+               int osd = osds[i];
+               u32 aff;
+
+               if (osd == CRUSH_ITEM_NONE)
+                       continue;
+
+               aff = osdmap->osd_primary_affinity[osd];
+               if (aff < CEPH_OSD_MAX_PRIMARY_AFFINITY &&
+                   (crush_hash32_2(CRUSH_HASH_RJENKINS1,
+                                   pps, osd) >> 16) >= aff) {
+                       /*
+                        * We chose not to use this primary.  Note it
+                        * anyway as a fallback in case we don't pick
+                        * anyone else, but keep looking.
+                        */
+                       if (pos < 0)
+                               pos = i;
+               } else {
+                       pos = i;
+                       break;
+               }
+       }
+       if (pos < 0)
+               return;
+
+       *primary = osds[pos];
+
+       if (ceph_can_shift_osds(pool) && pos > 0) {
+               /* move the new primary to the front */
+               for (i = pos; i > 0; i--)
+                       osds[i] = osds[i - 1];
+               osds[0] = *primary;
+       }
+}
+
+/*
+ * Given up set, apply pg_temp and primary_temp mappings.
+ *
+ * Return acting set length.  *primary is set to acting primary osd id,
+ * or -1 if acting set is empty.
+ */
+static int apply_temps(struct ceph_osdmap *osdmap,
+                      struct ceph_pg_pool_info *pool, struct ceph_pg pgid,
+                      int *osds, int len, int *primary)
+{
+       struct ceph_pg_mapping *pg;
+       int temp_len;
+       int temp_primary;
+       int i;
+
+       /* raw_pg -> pg */
+       pgid.seed = ceph_stable_mod(pgid.seed, pool->pg_num,
+                                   pool->pg_num_mask);
+
+       /* pg_temp? */
+       pg = __lookup_pg_mapping(&osdmap->pg_temp, pgid);
+       if (pg) {
+               temp_len = 0;
+               temp_primary = -1;
+
+               for (i = 0; i < pg->pg_temp.len; i++) {
+                       if (ceph_osd_is_down(osdmap, pg->pg_temp.osds[i])) {
+                               if (ceph_can_shift_osds(pool))
+                                       continue;
+                               else
+                                       osds[temp_len++] = CRUSH_ITEM_NONE;
+                       } else {
+                               osds[temp_len++] = pg->pg_temp.osds[i];
+                       }
+               }
+
+               /* apply pg_temp's primary */
+               for (i = 0; i < temp_len; i++) {
+                       if (osds[i] != CRUSH_ITEM_NONE) {
+                               temp_primary = osds[i];
+                               break;
+                       }
+               }
+       } else {
+               temp_len = len;
+               temp_primary = *primary;
+       }
+
+       /* primary_temp? */
+       pg = __lookup_pg_mapping(&osdmap->primary_temp, pgid);
+       if (pg)
+               temp_primary = pg->primary_temp.osd;
+
+       *primary = temp_primary;
+       return temp_len;
+}
+
+/*
+ * Calculate acting set for given pgid.
+ *
+ * Return acting set length, or error.  *primary is set to acting
+ * primary osd id, or -1 if acting set is empty or on error.
+ */
+int ceph_calc_pg_acting(struct ceph_osdmap *osdmap, struct ceph_pg pgid,
+                       int *osds, int *primary)
+{
+       struct ceph_pg_pool_info *pool;
+       u32 pps;
+       int len;
+
+       pool = __lookup_pg_pool(&osdmap->pg_pools, pgid.pool);
+       if (!pool) {
+               *primary = -1;
+               return -ENOENT;
+       }
+
+       if (pool->flags & CEPH_POOL_FLAG_HASHPSPOOL) {
+               /* hash pool id and seed so that pool PGs do not overlap */
+               pps = crush_hash32_2(CRUSH_HASH_RJENKINS1,
+                                    ceph_stable_mod(pgid.seed, pool->pgp_num,
+                                                    pool->pgp_num_mask),
+                                    pgid.pool);
+       } else {
+               /*
+                * legacy behavior: add ps and pool together.  this is
+                * not a great approach because the PGs from each pool
+                * will overlap on top of each other: 0.5 == 1.4 ==
+                * 2.3 == ...
+                */
+               pps = ceph_stable_mod(pgid.seed, pool->pgp_num,
+                                     pool->pgp_num_mask) +
+                       (unsigned)pgid.pool;
+       }
+
+       len = pg_to_raw_osds(osdmap, pool, pgid, pps, osds);
+       if (len < 0) {
+               *primary = -1;
+               return len;
+       }
+
+       len = raw_to_up_osds(osdmap, pool, osds, len, primary);
+
+       apply_primary_affinity(osdmap, pps, pool, osds, len, primary);
+
+       len = apply_temps(osdmap, pool, pgid, osds, len, primary);
+
+       return len;
+}
+
+/*
+ * Return primary osd for given pgid, or -1 if none.
+ */
+int ceph_calc_pg_primary(struct ceph_osdmap *osdmap, struct ceph_pg pgid)
+{
+       int osds[CEPH_PG_MAX_SIZE];
+       int primary;
+
+       ceph_calc_pg_acting(osdmap, pgid, osds, &primary);
+
+       return primary;
+}
+EXPORT_SYMBOL(ceph_calc_pg_primary);