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OpenCloudOS-Kernel/net/ceph/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)
{
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_8_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 | CEPH_OSD_EXISTS;
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);
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