diff options
Diffstat (limited to 'net/netfilter/ipset/ip_set_hash_gen.h')
-rw-r--r-- | net/netfilter/ipset/ip_set_hash_gen.h | 714 |
1 files changed, 442 insertions, 272 deletions
diff --git a/net/netfilter/ipset/ip_set_hash_gen.h b/net/netfilter/ipset/ip_set_hash_gen.h index 7952869..afe905c 100644 --- a/net/netfilter/ipset/ip_set_hash_gen.h +++ b/net/netfilter/ipset/ip_set_hash_gen.h @@ -10,19 +10,19 @@ #include <linux/rcupdate.h> #include <linux/jhash.h> +#include <linux/types.h> #include <linux/netfilter/ipset/ip_set_timeout.h> -#ifndef rcu_dereference_bh -#define rcu_dereference_bh(p) rcu_dereference(p) -#endif + +#define __ipset_dereference_protected(p, c) rcu_dereference_protected(p, c) +#define ipset_dereference_protected(p, set) \ + __ipset_dereference_protected(p, spin_is_locked(&(set)->lock)) #define rcu_dereference_bh_nfnl(p) rcu_dereference_bh_check(p, 1) /* Hashing which uses arrays to resolve clashing. The hash table is resized * (doubled) when searching becomes too long. * Internally jhash is used with the assumption that the size of the - * stored data is a multiple of sizeof(u32). If storage supports timeout, - * the timeout field must be the last one in the data structure - that field - * is ignored when computing the hash key. + * stored data is a multiple of sizeof(u32). * * Readers and resizing * @@ -35,7 +35,9 @@ /* Number of elements to store in an initial array block */ #define AHASH_INIT_SIZE 4 /* Max number of elements to store in an array block */ -#define AHASH_MAX_SIZE (3*AHASH_INIT_SIZE) +#define AHASH_MAX_SIZE (3 * AHASH_INIT_SIZE) +/* Max muber of elements in the array block when tuned */ +#define AHASH_MAX_TUNED 64 /* Max number of elements can be tuned */ #ifdef IP_SET_HASH_WITH_MULTI @@ -53,8 +55,9 @@ tune_ahash_max(u8 curr, u32 multi) /* Currently, at listing one hash bucket must fit into a message. * Therefore we have a hard limit here. */ - return n > curr && n <= 64 ? n : curr; + return n > curr && n <= AHASH_MAX_TUNED ? n : curr; } + #define TUNE_AHASH_MAX(h, multi) \ ((h)->ahash_max = tune_ahash_max((h)->ahash_max, multi)) #else @@ -64,18 +67,23 @@ tune_ahash_max(u8 curr, u32 multi) /* A hash bucket */ struct hbucket { - void *value; /* the array of the values */ + struct rcu_head rcu; /* for call_rcu_bh */ + /* Which positions are used in the array */ + DECLARE_BITMAP(used, AHASH_MAX_TUNED); u8 size; /* size of the array */ u8 pos; /* position of the first free entry */ -}; + unsigned char value[0]; /* the array of the values */ +} __attribute__ ((aligned)); /* The hash table: the table size stored here in order to make resizing easy */ struct htable { + atomic_t ref; /* References for resizing */ + atomic_t uref; /* References for dumping */ u8 htable_bits; /* size of hash table == 2^htable_bits */ - struct hbucket bucket[0]; /* hashtable buckets */ + struct hbucket __rcu *bucket[0]; /* hashtable buckets */ }; -#define hbucket(h, i) (&((h)->bucket[i])) +#define hbucket(h, i) ((h)->bucket[i]) #ifndef IPSET_NET_COUNT #define IPSET_NET_COUNT 1 @@ -83,8 +91,8 @@ struct htable { /* Book-keeping of the prefixes added to the set */ struct net_prefixes { - u32 nets[IPSET_NET_COUNT]; /* number of elements per cidr */ - u8 cidr[IPSET_NET_COUNT]; /* the different cidr values in the set */ + u32 nets[IPSET_NET_COUNT]; /* number of elements for this cidr */ + u8 cidr[IPSET_NET_COUNT]; /* the cidr value */ }; /* Compute the hash table size */ @@ -97,11 +105,11 @@ htable_size(u8 hbits) if (hbits > 31) return 0; hsize = jhash_size(hbits); - if ((((size_t)-1) - sizeof(struct htable))/sizeof(struct hbucket) + if ((((size_t)-1) - sizeof(struct htable)) / sizeof(struct hbucket *) < hsize) return 0; - return hsize * sizeof(struct hbucket) + sizeof(struct htable); + return hsize * sizeof(struct hbucket *) + sizeof(struct htable); } /* Compute htable_bits from the user input parameter hashsize */ @@ -110,6 +118,7 @@ htable_bits(u32 hashsize) { /* Assume that hashsize == 2^htable_bits */ u8 bits = fls(hashsize - 1); + if (jhash_size(bits) != hashsize) /* Round up to the first 2^n value */ bits = fls(hashsize); @@ -117,30 +126,6 @@ htable_bits(u32 hashsize) return bits; } -static int -hbucket_elem_add(struct hbucket *n, u8 ahash_max, size_t dsize) -{ - if (n->pos >= n->size) { - void *tmp; - - if (n->size >= ahash_max) - /* Trigger rehashing */ - return -EAGAIN; - - tmp = kzalloc((n->size + AHASH_INIT_SIZE) * dsize, - GFP_ATOMIC); - if (!tmp) - return -ENOMEM; - if (n->size) { - memcpy(tmp, n->value, n->size * dsize); - kfree(n->value); - } - n->value = tmp; - n->size += AHASH_INIT_SIZE; - } - return 0; -} - #ifdef IP_SET_HASH_WITH_NETS #if IPSET_NET_COUNT > 1 #define __CIDR(cidr, i) (cidr[i]) @@ -149,17 +134,21 @@ hbucket_elem_add(struct hbucket *n, u8 ahash_max, size_t dsize) #endif /* cidr + 1 is stored in net_prefixes to support /0 */ -#define SCIDR(cidr, i) (__CIDR(cidr, i) + 1) +#define NCIDR_PUT(cidr) ((cidr) + 1) +#define NCIDR_GET(cidr) ((cidr) - 1) #ifdef IP_SET_HASH_WITH_NETS_PACKED /* When cidr is packed with nomatch, cidr - 1 is stored in the data entry */ -#define GCIDR(cidr, i) (__CIDR(cidr, i) + 1) -#define NCIDR(cidr) (cidr) +#define DCIDR_PUT(cidr) ((cidr) - 1) +#define DCIDR_GET(cidr, i) (__CIDR(cidr, i) + 1) #else -#define GCIDR(cidr, i) (__CIDR(cidr, i)) -#define NCIDR(cidr) (cidr - 1) +#define DCIDR_PUT(cidr) (cidr) +#define DCIDR_GET(cidr, i) __CIDR(cidr, i) #endif +#define INIT_CIDR(cidr, host_mask) \ + DCIDR_PUT(((cidr) ? NCIDR_GET(cidr) : host_mask)) + #define SET_HOST_MASK(family) (family == AF_INET ? 32 : 128) #ifdef IP_SET_HASH_WITH_NET0 @@ -203,6 +192,7 @@ hbucket_elem_add(struct hbucket *n, u8 ahash_max, size_t dsize) #undef mtype_del #undef mtype_test_cidrs #undef mtype_test +#undef mtype_uref #undef mtype_expire #undef mtype_resize #undef mtype_head @@ -244,6 +234,7 @@ hbucket_elem_add(struct hbucket *n, u8 ahash_max, size_t dsize) #define mtype_del IPSET_TOKEN(MTYPE, _del) #define mtype_test_cidrs IPSET_TOKEN(MTYPE, _test_cidrs) #define mtype_test IPSET_TOKEN(MTYPE, _test) +#define mtype_uref IPSET_TOKEN(MTYPE, _uref) #define mtype_expire IPSET_TOKEN(MTYPE, _expire) #define mtype_resize IPSET_TOKEN(MTYPE, _resize) #define mtype_head IPSET_TOKEN(MTYPE, _head) @@ -266,7 +257,7 @@ hbucket_elem_add(struct hbucket *n, u8 ahash_max, size_t dsize) #endif #define HKEY(data, initval, htable_bits) \ -(jhash2((u32 *)(data), HKEY_DATALEN/sizeof(u32), initval) \ +(jhash2((u32 *)(data), HKEY_DATALEN / sizeof(u32), initval) \ & jhash_mask(htable_bits)) #ifndef htype @@ -292,9 +283,6 @@ struct htype { #ifdef IP_SET_HASH_WITH_NETMASK u8 netmask; /* netmask value for subnets to store */ #endif -#ifdef IP_SET_HASH_WITH_RBTREE - struct rb_root rbtree; -#endif #ifdef IP_SET_HASH_WITH_NETS struct net_prefixes nets[0]; /* book-keeping of prefixes */ #endif @@ -303,7 +291,8 @@ struct htype { #ifdef IP_SET_HASH_WITH_NETS /* Network cidr size book keeping when the hash stores different - * sized networks */ + * sized networks. cidr == real cidr + 1 to support /0. + */ static void mtype_add_cidr(struct htype *h, u8 cidr, u8 nets_length, u8 n) { @@ -311,11 +300,11 @@ mtype_add_cidr(struct htype *h, u8 cidr, u8 nets_length, u8 n) /* Add in increasing prefix order, so larger cidr first */ for (i = 0, j = -1; i < nets_length && h->nets[i].cidr[n]; i++) { - if (j != -1) + if (j != -1) { continue; - else if (h->nets[i].cidr[n] < cidr) + } else if (h->nets[i].cidr[n] < cidr) { j = i; - else if (h->nets[i].cidr[n] == cidr) { + } else if (h->nets[i].cidr[n] == cidr) { h->nets[cidr - 1].nets[n]++; return; } @@ -334,15 +323,15 @@ mtype_del_cidr(struct htype *h, u8 cidr, u8 nets_length, u8 n) u8 i, j, net_end = nets_length - 1; for (i = 0; i < nets_length; i++) { - if (h->nets[i].cidr[n] != cidr) - continue; - h->nets[cidr -1].nets[n]--; - if (h->nets[cidr -1].nets[n] > 0) - return; + if (h->nets[i].cidr[n] != cidr) + continue; + h->nets[cidr - 1].nets[n]--; + if (h->nets[cidr - 1].nets[n] > 0) + return; for (j = i; j < net_end && h->nets[j].cidr[n]; j++) - h->nets[j].cidr[n] = h->nets[j + 1].cidr[n]; + h->nets[j].cidr[n] = h->nets[j + 1].cidr[n]; h->nets[j].cidr[n] = 0; - return; + return; } } #endif @@ -353,15 +342,18 @@ mtype_ahash_memsize(const struct htype *h, const struct htable *t, u8 nets_length, size_t dsize) { u32 i; - size_t memsize = sizeof(*h) - + sizeof(*t) + struct hbucket *n; + size_t memsize = sizeof(*h) + sizeof(*t); + #ifdef IP_SET_HASH_WITH_NETS - + sizeof(struct net_prefixes) * nets_length + memsize += sizeof(struct net_prefixes) * nets_length; #endif - + jhash_size(t->htable_bits) * sizeof(struct hbucket); - - for (i = 0; i < jhash_size(t->htable_bits); i++) - memsize += t->bucket[i].size * dsize; + for (i = 0; i < jhash_size(t->htable_bits); i++) { + n = rcu_dereference_bh(hbucket(t, i)); + if (!n) + continue; + memsize += sizeof(struct hbucket) + n->size * dsize; + } return memsize; } @@ -376,7 +368,8 @@ mtype_ext_cleanup(struct ip_set *set, struct hbucket *n) int i; for (i = 0; i < n->pos; i++) - ip_set_ext_destroy(set, ahash_data(n, i, set->dsize)); + if (test_bit(i, n->used)) + ip_set_ext_destroy(set, ahash_data(n, i, set->dsize)); } /* Flush a hash type of set: destroy all elements */ @@ -388,16 +381,16 @@ mtype_flush(struct ip_set *set) struct hbucket *n; u32 i; - t = rcu_dereference_bh_nfnl(h->table); + t = ipset_dereference_protected(h->table, set); for (i = 0; i < jhash_size(t->htable_bits); i++) { - n = hbucket(t, i); - if (n->size) { - if (set->extensions & IPSET_EXT_DESTROY) - mtype_ext_cleanup(set, n); - n->size = n->pos = 0; - /* FIXME: use slab cache */ - kfree(n->value); - } + n = __ipset_dereference_protected(hbucket(t, i), 1); + if (!n) + continue; + if (set->extensions & IPSET_EXT_DESTROY) + mtype_ext_cleanup(set, n); + /* FIXME: use slab cache */ + rcu_assign_pointer(hbucket(t, i), NULL); + kfree_rcu(n, rcu); } #ifdef IP_SET_HASH_WITH_NETS memset(h->nets, 0, sizeof(struct net_prefixes) * NLEN(set->family)); @@ -413,13 +406,13 @@ mtype_ahash_destroy(struct ip_set *set, struct htable *t, bool ext_destroy) u32 i; for (i = 0; i < jhash_size(t->htable_bits); i++) { - n = hbucket(t, i); - if (n->size) { - if (set->extensions & IPSET_EXT_DESTROY && ext_destroy) - mtype_ext_cleanup(set, n); - /* FIXME: use slab cache */ - kfree(n->value); - } + n = __ipset_dereference_protected(hbucket(t, i), 1); + if (!n) + continue; + if (set->extensions & IPSET_EXT_DESTROY && ext_destroy) + mtype_ext_cleanup(set, n); + /* FIXME: use slab cache */ + kfree(n); } ip_set_free(t); @@ -431,13 +424,11 @@ mtype_destroy(struct ip_set *set) { struct htype *h = set->data; - if (set->extensions & IPSET_EXT_TIMEOUT) + if (SET_WITH_TIMEOUT(set)) del_timer_sync(&h->gc); - mtype_ahash_destroy(set, rcu_dereference_bh_nfnl(h->table), true); -#ifdef IP_SET_HASH_WITH_RBTREE - rbtree_destroy(&h->rbtree); -#endif + mtype_ahash_destroy(set, + __ipset_dereference_protected(h->table, 1), true); kfree(h); set->data = NULL; @@ -449,7 +440,7 @@ mtype_gc_init(struct ip_set *set, void (*gc)(unsigned long ul_set)) struct htype *h = set->data; init_timer(&h->gc); - h->gc.data = (unsigned long) set; + h->gc.data = (unsigned long)set; h->gc.function = gc; h->gc.expires = jiffies + IPSET_GC_PERIOD(set->timeout) * HZ; add_timer(&h->gc); @@ -482,61 +473,71 @@ mtype_expire(struct ip_set *set, struct htype *h, u8 nets_length, size_t dsize) struct htable *t; struct hbucket *n; struct mtype_elem *data; - u32 i; - int j; + u32 i, j, d; #ifdef IP_SET_HASH_WITH_NETS u8 k; #endif - rcu_read_lock_bh(); - t = rcu_dereference_bh(h->table); + t = ipset_dereference_protected(h->table, set); for (i = 0; i < jhash_size(t->htable_bits); i++) { - n = hbucket(t, i); - for (j = 0; j < n->pos; j++) { + n = __ipset_dereference_protected(hbucket(t, i), 1); + if (!n) + continue; + for (j = 0, d = 0; j < n->pos; j++) { + if (!test_bit(j, n->used)) { + d++; + continue; + } data = ahash_data(n, j, dsize); if (ip_set_timeout_expired(ext_timeout(data, set))) { pr_debug("expired %u/%u\n", i, j); + clear_bit(j, n->used); + smp_mb__after_atomic(); #ifdef IP_SET_HASH_WITH_NETS for (k = 0; k < IPSET_NET_COUNT; k++) - mtype_del_cidr(h, SCIDR(data->cidr, k), - nets_length, k); + mtype_del_cidr(h, + NCIDR_PUT(DCIDR_GET(data->cidr, + k)), + nets_length, k); #endif ip_set_ext_destroy(set, data); - if (j != n->pos - 1) - /* Not last one */ - memcpy(data, - ahash_data(n, n->pos - 1, dsize), - dsize); - n->pos--; h->elements--; + d++; } } - if (n->pos + AHASH_INIT_SIZE < n->size) { - void *tmp = kzalloc((n->size - AHASH_INIT_SIZE) - * dsize, - GFP_ATOMIC); + if (d >= AHASH_INIT_SIZE) { + struct hbucket *tmp = kzalloc(sizeof(*tmp) + + (n->size - AHASH_INIT_SIZE) * dsize, + GFP_ATOMIC); if (!tmp) /* Still try to delete expired elements */ continue; - n->size -= AHASH_INIT_SIZE; - memcpy(tmp, n->value, n->size * dsize); - kfree(n->value); - n->value = tmp; + tmp->size = n->size - AHASH_INIT_SIZE; + for (j = 0, d = 0; j < n->pos; j++) { + if (!test_bit(j, n->used)) + continue; + data = ahash_data(n, j, dsize); + memcpy(tmp->value + d * dsize, data, dsize); + set_bit(j, tmp->used); + d++; + } + tmp->pos = d; + rcu_assign_pointer(hbucket(t, i), tmp); + kfree_rcu(n, rcu); } } - rcu_read_unlock_bh(); } static void mtype_gc(unsigned long ul_set) { - struct ip_set *set = (struct ip_set *) ul_set; + struct ip_set *set = (struct ip_set *)ul_set; struct htype *h = set->data; pr_debug("called\n"); - write_lock_bh(&set->lock); + spin_lock_bh(&set->lock); mtype_expire(set, h, NLEN(set->family), set->dsize); - write_unlock_bh(&set->lock); + spin_unlock_bh(&set->lock); h->gc.expires = jiffies + IPSET_GC_PERIOD(set->timeout) * HZ; add_timer(&h->gc); @@ -544,93 +545,152 @@ mtype_gc(unsigned long ul_set) /* Resize a hash: create a new hash table with doubling the hashsize * and inserting the elements to it. Repeat until we succeed or - * fail due to memory pressures. */ + * fail due to memory pressures. + */ static int mtype_resize(struct ip_set *set, bool retried) { struct htype *h = set->data; - struct htable *t, *orig = rcu_dereference_bh_nfnl(h->table); - u8 htable_bits = orig->htable_bits; + struct htable *t, *orig; + u8 htable_bits; + size_t dsize = set->dsize; #ifdef IP_SET_HASH_WITH_NETS u8 flags; + struct mtype_elem *tmp; #endif struct mtype_elem *data; struct mtype_elem *d; struct hbucket *n, *m; - u32 i, j; + u32 i, j, key; int ret; - /* Try to cleanup once */ - if (SET_WITH_TIMEOUT(set) && !retried) { - i = h->elements; - write_lock_bh(&set->lock); - mtype_expire(set, set->data, NLEN(set->family), set->dsize); - write_unlock_bh(&set->lock); - if (h->elements < i) - return 0; - } +#ifdef IP_SET_HASH_WITH_NETS + tmp = kmalloc(dsize, GFP_KERNEL); + if (!tmp) + return -ENOMEM; +#endif + rcu_read_lock_bh(); + orig = rcu_dereference_bh_nfnl(h->table); + htable_bits = orig->htable_bits; + rcu_read_unlock_bh(); retry: ret = 0; htable_bits++; - pr_debug("attempt to resize set %s from %u to %u, t %p\n", - set->name, orig->htable_bits, htable_bits, orig); if (!htable_bits) { /* In case we have plenty of memory :-) */ pr_warn("Cannot increase the hashsize of set %s further\n", set->name); - return -IPSET_ERR_HASH_FULL; + ret = -IPSET_ERR_HASH_FULL; + goto out; + } + t = ip_set_alloc(htable_size(htable_bits)); + if (!t) { + ret = -ENOMEM; + goto out; } - t = ip_set_alloc(sizeof(*t) - + jhash_size(htable_bits) * sizeof(struct hbucket)); - if (!t) - return -ENOMEM; t->htable_bits = htable_bits; - read_lock_bh(&set->lock); + spin_lock_bh(&set->lock); + orig = __ipset_dereference_protected(h->table, 1); + /* There can't be another parallel resizing, but dumping is possible */ + atomic_set(&orig->ref, 1); + atomic_inc(&orig->uref); + pr_debug("attempt to resize set %s from %u to %u, t %p\n", + set->name, orig->htable_bits, htable_bits, orig); for (i = 0; i < jhash_size(orig->htable_bits); i++) { - n = hbucket(orig, i); + n = __ipset_dereference_protected(hbucket(orig, i), 1); + if (!n) + continue; for (j = 0; j < n->pos; j++) { - data = ahash_data(n, j, set->dsize); + if (!test_bit(j, n->used)) + continue; + data = ahash_data(n, j, dsize); #ifdef IP_SET_HASH_WITH_NETS + /* We have readers running parallel with us, + * so the live data cannot be modified. + */ flags = 0; + memcpy(tmp, data, dsize); + data = tmp; mtype_data_reset_flags(data, &flags); #endif - m = hbucket(t, HKEY(data, h->initval, htable_bits)); - ret = hbucket_elem_add(m, AHASH_MAX(h), set->dsize); - if (ret < 0) { -#ifdef IP_SET_HASH_WITH_NETS - mtype_data_reset_flags(data, &flags); -#endif - read_unlock_bh(&set->lock); - mtype_ahash_destroy(set, t, false); - if (ret == -EAGAIN) - goto retry; - return ret; + key = HKEY(data, h->initval, htable_bits); + m = __ipset_dereference_protected(hbucket(t, key), 1); + if (!m) { + m = kzalloc(sizeof(*m) + + AHASH_INIT_SIZE * dsize, + GFP_ATOMIC); + if (!m) { + ret = -ENOMEM; + goto cleanup; + } + m->size = AHASH_INIT_SIZE; + RCU_INIT_POINTER(hbucket(t, key), m); + } else if (m->pos >= m->size) { + struct hbucket *ht; + + if (m->size >= AHASH_MAX(h)) { + ret = -EAGAIN; + } else { + ht = kzalloc(sizeof(*ht) + + (m->size + AHASH_INIT_SIZE) + * dsize, + GFP_ATOMIC); + if (!ht) + ret = -ENOMEM; + } + if (ret < 0) + goto cleanup; + memcpy(ht, m, sizeof(struct hbucket) + + m->size * dsize); + ht->size = m->size + AHASH_INIT_SIZE; + kfree(m); + m = ht; + RCU_INIT_POINTER(hbucket(t, key), ht); } - d = ahash_data(m, m->pos++, set->dsize); - memcpy(d, data, set->dsize); + d = ahash_data(m, m->pos, dsize); + memcpy(d, data, dsize); + set_bit(m->pos++, m->used); #ifdef IP_SET_HASH_WITH_NETS mtype_data_reset_flags(d, &flags); #endif } } - rcu_assign_pointer(h->table, t); - read_unlock_bh(&set->lock); + + spin_unlock_bh(&set->lock); /* Give time to other readers of the set */ synchronize_rcu_bh(); pr_debug("set %s resized from %u (%p) to %u (%p)\n", set->name, orig->htable_bits, orig, t->htable_bits, t); - mtype_ahash_destroy(set, orig, false); + /* If there's nobody else dumping the table, destroy it */ + if (atomic_dec_and_test(&orig->uref)) { + pr_debug("Table destroy by resize %p\n", orig); + mtype_ahash_destroy(set, orig, false); + } - return 0; +out: +#ifdef IP_SET_HASH_WITH_NETS + kfree(tmp); +#endif + return ret; + +cleanup: + atomic_set(&orig->ref, 0); + atomic_dec(&orig->uref); + spin_unlock_bh(&set->lock); + mtype_ahash_destroy(set, t, false); + if (ret == -EAGAIN) + goto retry; + goto out; } /* Add an element to a hash and update the internal counters when succeeded, - * otherwise report the proper error code. */ + * otherwise report the proper error code. + */ static int mtype_add(struct ip_set *set, void *value, const struct ip_set_ext *ext, struct ip_set_ext *mext, u32 flags) @@ -639,17 +699,49 @@ mtype_add(struct ip_set *set, void *value, const struct ip_set_ext *ext, struct htable *t; const struct mtype_elem *d = value; struct mtype_elem *data; - struct hbucket *n; - int i, ret = 0; - int j = AHASH_MAX(h) + 1; + struct hbucket *n, *old = ERR_PTR(-ENOENT); + int i, j = -1; bool flag_exist = flags & IPSET_FLAG_EXIST; + bool deleted = false, forceadd = false, reuse = false; u32 key, multi = 0; - rcu_read_lock_bh(); - t = rcu_dereference_bh(h->table); + if (h->elements >= h->maxelem) { + if (SET_WITH_TIMEOUT(set)) + /* FIXME: when set is full, we slow down here */ + mtype_expire(set, h, NLEN(set->family), set->dsize); + if (h->elements >= h->maxelem && SET_WITH_FORCEADD(set)) + forceadd = true; + } + + t = ipset_dereference_protected(h->table, set); key = HKEY(value, h->initval, t->htable_bits); - n = hbucket(t, key); + n = __ipset_dereference_protected(hbucket(t, key), 1); + if (!n) { + if (forceadd) { + if (net_ratelimit()) + pr_warn("Set %s is full, maxelem %u reached\n", + set->name, h->maxelem); + return -IPSET_ERR_HASH_FULL; + } else if (h->elements >= h->maxelem) { + goto set_full; + } + old = NULL; + n = kzalloc(sizeof(*n) + AHASH_INIT_SIZE * set->dsize, + GFP_ATOMIC); + if (!n) + return -ENOMEM; + n->size = AHASH_INIT_SIZE; + goto copy_elem; + } for (i = 0; i < n->pos; i++) { + if (!test_bit(i, n->used)) { + /* Reuse first deleted entry */ + if (j == -1) { + deleted = reuse = true; + j = i; + } + continue; + } data = ahash_data(n, i, set->dsize); if (mtype_data_equal(data, d, &multi)) { if (flag_exist || @@ -657,85 +749,94 @@ mtype_add(struct ip_set *set, void *value, const struct ip_set_ext *ext, ip_set_timeout_expired(ext_timeout(data, set)))) { /* Just the extensions could be overwritten */ j = i; - goto reuse_slot; - } else { - ret = -IPSET_ERR_EXIST; - goto out; + goto overwrite_extensions; } + return -IPSET_ERR_EXIST; } /* Reuse first timed out entry */ if (SET_WITH_TIMEOUT(set) && ip_set_timeout_expired(ext_timeout(data, set)) && - j != AHASH_MAX(h) + 1) + j == -1) { j = i; + reuse = true; + } } - if (h->elements >= h->maxelem && SET_WITH_FORCEADD(set) && n->pos) { - /* Choosing the first entry in the array to replace */ - j = 0; - goto reuse_slot; - } - if (SET_WITH_TIMEOUT(set) && h->elements >= h->maxelem) - /* FIXME: when set is full, we slow down here */ - mtype_expire(set, h, NLEN(set->family), set->dsize); - - if (h->elements >= h->maxelem) { - if (net_ratelimit()) - pr_warn("Set %s is full, maxelem %u reached\n", - set->name, h->maxelem); - ret = -IPSET_ERR_HASH_FULL; - goto out; - } - -reuse_slot: - if (j != AHASH_MAX(h) + 1) { - /* Fill out reused slot */ + if (reuse || forceadd) { data = ahash_data(n, j, set->dsize); + if (!deleted) { #ifdef IP_SET_HASH_WITH_NETS - for (i = 0; i < IPSET_NET_COUNT; i++) { - mtype_del_cidr(h, SCIDR(data->cidr, i), - NLEN(set->family), i); - mtype_add_cidr(h, SCIDR(d->cidr, i), - NLEN(set->family), i); - } + for (i = 0; i < IPSET_NET_COUNT; i++) + mtype_del_cidr(h, + NCIDR_PUT(DCIDR_GET(data->cidr, i)), + NLEN(set->family), i); #endif - ip_set_ext_destroy(set, data); - } else { - /* Use/create a new slot */ + ip_set_ext_destroy(set, data); + h->elements--; + } + goto copy_data; + } + if (h->elements >= h->maxelem) + goto set_full; + /* Create a new slot */ + if (n->pos >= n->size) { TUNE_AHASH_MAX(h, multi); - ret = hbucket_elem_add(n, AHASH_MAX(h), set->dsize); - if (ret != 0) { - if (ret == -EAGAIN) - mtype_data_next(&h->next, d); - goto out; + if (n->size >= AHASH_MAX(h)) { + /* Trigger rehashing */ + mtype_data_next(&h->next, d); + return -EAGAIN; } - data = ahash_data(n, n->pos++, set->dsize); + old = n; + n = kzalloc(sizeof(*n) + + (old->size + AHASH_INIT_SIZE) * set->dsize, + GFP_ATOMIC); + if (!n) + return -ENOMEM; + memcpy(n, old, sizeof(struct hbucket) + + old->size * set->dsize); + n->size = old->size + AHASH_INIT_SIZE; + } + +copy_elem: + j = n->pos++; + data = ahash_data(n, j, set->dsize); +copy_data: + h->elements++; #ifdef IP_SET_HASH_WITH_NETS - for (i = 0; i < IPSET_NET_COUNT; i++) - mtype_add_cidr(h, SCIDR(d->cidr, i), NLEN(set->family), - i); + for (i = 0; i < IPSET_NET_COUNT; i++) + mtype_add_cidr(h, NCIDR_PUT(DCIDR_GET(d->cidr, i)), + NLEN(set->family), i); #endif - h->elements++; - } memcpy(data, d, sizeof(struct mtype_elem)); +overwrite_extensions: #ifdef IP_SET_HASH_WITH_NETS mtype_data_set_flags(data, flags); #endif - if (SET_WITH_TIMEOUT(set)) - ip_set_timeout_set(ext_timeout(data, set), ext->timeout); if (SET_WITH_COUNTER(set)) ip_set_init_counter(ext_counter(data, set), ext); if (SET_WITH_COMMENT(set)) ip_set_init_comment(ext_comment(data, set), ext); if (SET_WITH_SKBINFO(set)) ip_set_init_skbinfo(ext_skbinfo(data, set), ext); + /* Must come last for the case when timed out entry is reused */ + if (SET_WITH_TIMEOUT(set)) + ip_set_timeout_set(ext_timeout(data, set), ext->timeout); + smp_mb__before_atomic(); + set_bit(j, n->used); + if (old != ERR_PTR(-ENOENT)) { + rcu_assign_pointer(hbucket(t, key), n); + if (old) + kfree_rcu(old, rcu); + } -out: - rcu_read_unlock_bh(); - return ret; + return 0; +set_full: + if (net_ratelimit()) + pr_warn("Set %s is full, maxelem %u reached\n", + set->name, h->maxelem); + return -IPSET_ERR_HASH_FULL; } -/* Delete an element from the hash: swap it with the last element - * and free up space if possible. +/* Delete an element from the hash and free up space if possible. */ static int mtype_del(struct ip_set *set, void *value, const struct ip_set_ext *ext, @@ -746,55 +847,70 @@ mtype_del(struct ip_set *set, void *value, const struct ip_set_ext *ext, const struct mtype_elem *d = value; struct mtype_elem *data; struct hbucket *n; - int i, ret = -IPSET_ERR_EXIST; -#ifdef IP_SET_HASH_WITH_NETS - u8 j; -#endif + int i, j, k, ret = -IPSET_ERR_EXIST; u32 key, multi = 0; + size_t dsize = set->dsize; - rcu_read_lock_bh(); - t = rcu_dereference_bh(h->table); + t = ipset_dereference_protected(h->table, set); key = HKEY(value, h->initval, t->htable_bits); - n = hbucket(t, key); - for (i = 0; i < n->pos; i++) { - data = ahash_data(n, i, set->dsize); + n = __ipset_dereference_protected(hbucket(t, key), 1); + if (!n) + goto out; + for (i = 0, k = 0; i < n->pos; i++) { + if (!test_bit(i, n->used)) { + k++; + continue; + } + data = ahash_data(n, i, dsize); if (!mtype_data_equal(data, d, &multi)) continue; if (SET_WITH_TIMEOUT(set) && ip_set_timeout_expired(ext_timeout(data, set))) goto out; - if (i != n->pos - 1) - /* Not last one */ - memcpy(data, ahash_data(n, n->pos - 1, set->dsize), - set->dsize); - n->pos--; + ret = 0; + clear_bit(i, n->used); + smp_mb__after_atomic(); + if (i + 1 == n->pos) + n->pos--; h->elements--; #ifdef IP_SET_HASH_WITH_NETS for (j = 0; j < IPSET_NET_COUNT; j++) - mtype_del_cidr(h, SCIDR(d->cidr, j), NLEN(set->family), - j); + mtype_del_cidr(h, NCIDR_PUT(DCIDR_GET(d->cidr, j)), + NLEN(set->family), j); #endif ip_set_ext_destroy(set, data); - if (n->pos + AHASH_INIT_SIZE < n->size) { - void *tmp = kzalloc((n->size - AHASH_INIT_SIZE) - * set->dsize, - GFP_ATOMIC); - if (!tmp) { - ret = 0; + + for (; i < n->pos; i++) { + if (!test_bit(i, n->used)) + k++; + } + if (n->pos == 0 && k == 0) { + rcu_assign_pointer(hbucket(t, key), NULL); + kfree_rcu(n, rcu); + } else if (k >= AHASH_INIT_SIZE) { + struct hbucket *tmp = kzalloc(sizeof(*tmp) + + (n->size - AHASH_INIT_SIZE) * dsize, + GFP_ATOMIC); + if (!tmp) goto out; + tmp->size = n->size - AHASH_INIT_SIZE; + for (j = 0, k = 0; j < n->pos; j++) { + if (!test_bit(j, n->used)) + continue; + data = ahash_data(n, j, dsize); + memcpy(tmp->value + k * dsize, data, dsize); + set_bit(j, tmp->used); + k++; } - n->size -= AHASH_INIT_SIZE; - memcpy(tmp, n->value, n->size * set->dsize); - kfree(n->value); - n->value = tmp; + tmp->pos = k; + rcu_assign_pointer(hbucket(t, key), tmp); + kfree_rcu(n, rcu); } - ret = 0; goto out; } out: - rcu_read_unlock_bh(); return ret; } @@ -813,7 +929,8 @@ mtype_data_match(struct mtype_elem *data, const struct ip_set_ext *ext, #ifdef IP_SET_HASH_WITH_NETS /* Special test function which takes into account the different network - * sizes added to the set */ + * sizes added to the set + */ static int mtype_test_cidrs(struct ip_set *set, struct mtype_elem *d, const struct ip_set_ext *ext, @@ -836,16 +953,21 @@ mtype_test_cidrs(struct ip_set *set, struct mtype_elem *d, for (; j < nets_length && h->nets[j].cidr[0] && !multi; j++) { #if IPSET_NET_COUNT == 2 mtype_data_reset_elem(d, &orig); - mtype_data_netmask(d, NCIDR(h->nets[j].cidr[0]), false); + mtype_data_netmask(d, NCIDR_GET(h->nets[j].cidr[0]), false); for (k = 0; k < nets_length && h->nets[k].cidr[1] && !multi; k++) { - mtype_data_netmask(d, NCIDR(h->nets[k].cidr[1]), true); + mtype_data_netmask(d, NCIDR_GET(h->nets[k].cidr[1]), + true); #else - mtype_data_netmask(d, NCIDR(h->nets[j].cidr[0])); + mtype_data_netmask(d, NCIDR_GET(h->nets[j].cidr[0])); #endif key = HKEY(d, h->initval, t->htable_bits); - n = hbucket(t, key); + n = rcu_dereference_bh(hbucket(t, key)); + if (!n) + continue; for (i = 0; i < n->pos; i++) { + if (!test_bit(i, n->used)) + continue; data = ahash_data(n, i, set->dsize); if (!mtype_data_equal(data, d, &multi)) continue; @@ -883,13 +1005,13 @@ mtype_test(struct ip_set *set, void *value, const struct ip_set_ext *ext, int i, ret = 0; u32 key, multi = 0; - rcu_read_lock_bh(); t = rcu_dereference_bh(h->table); #ifdef IP_SET_HASH_WITH_NETS /* If we test an IP address and not a network address, - * try all possible network sizes */ + * try all possible network sizes + */ for (i = 0; i < IPSET_NET_COUNT; i++) - if (GCIDR(d->cidr, i) != SET_HOST_MASK(set->family)) + if (DCIDR_GET(d->cidr, i) != SET_HOST_MASK(set->family)) break; if (i == IPSET_NET_COUNT) { ret = mtype_test_cidrs(set, d, ext, mext, flags); @@ -898,8 +1020,14 @@ mtype_test(struct ip_set *set, void *value, const struct ip_set_ext *ext, #endif key = HKEY(d, h->initval, t->htable_bits); - n = hbucket(t, key); + n = rcu_dereference_bh(hbucket(t, key)); + if (!n) { + ret = 0; + goto out; + } for (i = 0; i < n->pos; i++) { + if (!test_bit(i, n->used)) + continue; data = ahash_data(n, i, set->dsize); if (mtype_data_equal(data, d, &multi) && !(SET_WITH_TIMEOUT(set) && @@ -909,7 +1037,6 @@ mtype_test(struct ip_set *set, void *value, const struct ip_set_ext *ext, } } out: - rcu_read_unlock_bh(); return ret; } @@ -921,15 +1048,19 @@ mtype_head(struct ip_set *set, struct sk_buff *skb) const struct htable *t; struct nlattr *nested; size_t memsize; + u8 htable_bits; + rcu_read_lock_bh(); t = rcu_dereference_bh_nfnl(h->table); memsize = mtype_ahash_memsize(h, t, NLEN(set->family), set->dsize); + htable_bits = t->htable_bits; + rcu_read_unlock_bh(); nested = ipset_nest_start(skb, IPSET_ATTR_DATA); if (!nested) goto nla_put_failure; if (nla_put_net32(skb, IPSET_ATTR_HASHSIZE, - htonl(jhash_size(t->htable_bits))) || + htonl(jhash_size(htable_bits))) || nla_put_net32(skb, IPSET_ATTR_MAXELEM, htonl(h->maxelem))) goto nla_put_failure; #ifdef IP_SET_HASH_WITH_NETMASK @@ -953,32 +1084,63 @@ nla_put_failure: return -EMSGSIZE; } +/* Make possible to run dumping parallel with resizing */ +static void +mtype_uref(struct ip_set *set, struct netlink_callback *cb, bool start) +{ + struct htype *h = set->data; + struct htable *t; + + if (start) { + rcu_read_lock_bh(); + t = rcu_dereference_bh_nfnl(h->table); + atomic_inc(&t->uref); + cb->args[IPSET_CB_PRIVATE] = (unsigned long)t; + rcu_read_unlock_bh(); + } else if (cb->args[IPSET_CB_PRIVATE]) { + t = (struct htable *)cb->args[IPSET_CB_PRIVATE]; + if (atomic_dec_and_test(&t->uref) && atomic_read(&t->ref)) { + /* Resizing didn't destroy the hash table */ + pr_debug("Table destroy by dump: %p\n", t); + mtype_ahash_destroy(set, t, false); + } + cb->args[IPSET_CB_PRIVATE] = 0; + } +} + /* Reply a LIST/SAVE request: dump the elements of the specified set */ static int mtype_list(const struct ip_set *set, struct sk_buff *skb, struct netlink_callback *cb) { - const struct htype *h = set->data; - const struct htable *t = rcu_dereference_bh_nfnl(h->table); + const struct htable *t; struct nlattr *atd, *nested; const struct hbucket *n; const struct mtype_elem *e; u32 first = cb->args[IPSET_CB_ARG0]; /* We assume that one hash bucket fills into one page */ void *incomplete; - int i; + int i, ret = 0; atd = ipset_nest_start(skb, IPSET_ATTR_ADT); if (!atd) return -EMSGSIZE; + pr_debug("list hash set %s\n", set->name); + t = (const struct htable *)cb->args[IPSET_CB_PRIVATE]; + /* Expire may replace a hbucket with another one */ + rcu_read_lock(); for (; cb->args[IPSET_CB_ARG0] < jhash_size(t->htable_bits); cb->args[IPSET_CB_ARG0]++) { incomplete = skb_tail_pointer(skb); - n = hbucket(t, cb->args[IPSET_CB_ARG0]); + n = rcu_dereference(hbucket(t, cb->args[IPSET_CB_ARG0])); pr_debug("cb->arg bucket: %lu, t %p n %p\n", cb->args[IPSET_CB_ARG0], t, n); + if (!n) + continue; for (i = 0; i < n->pos; i++) { + if (!test_bit(i, n->used)) + continue; e = ahash_data(n, i, set->dsize); if (SET_WITH_TIMEOUT(set) && ip_set_timeout_expired(ext_timeout(e, set))) @@ -989,9 +1151,10 @@ mtype_list(const struct ip_set *set, if (!nested) { if (cb->args[IPSET_CB_ARG0] == first) { nla_nest_cancel(skb, atd); - return -EMSGSIZE; - } else - goto nla_put_failure; + ret = -EMSGSIZE; + goto out; + } + goto nla_put_failure; } if (mtype_data_list(skb, e)) goto nla_put_failure; @@ -1004,7 +1167,7 @@ mtype_list(const struct ip_set *set, /* Set listing finished */ cb->args[IPSET_CB_ARG0] = 0; - return 0; + goto out; nla_put_failure: nlmsg_trim(skb, incomplete); @@ -1012,20 +1175,24 @@ nla_put_failure: pr_warn("Can't list set %s: one bucket does not fit into a message. Please report it!\n", set->name); cb->args[IPSET_CB_ARG0] = 0; - return -EMSGSIZE; + ret = -EMSGSIZE; + } else { + ipset_nest_end(skb, atd); } - ipset_nest_end(skb, atd); - return 0; +out: + rcu_read_unlock(); + return ret; } static int IPSET_TOKEN(MTYPE, _kadt)(struct ip_set *set, const struct sk_buff *skb, - const struct xt_action_param *par, - enum ipset_adt adt, struct ip_set_adt_opt *opt); + const struct xt_action_param *par, + enum ipset_adt adt, struct ip_set_adt_opt *opt); static int IPSET_TOKEN(MTYPE, _uadt)(struct ip_set *set, struct nlattr *tb[], - enum ipset_adt adt, u32 *lineno, u32 flags, bool retried); + enum ipset_adt adt, u32 *lineno, u32 flags, + bool retried); static const struct ip_set_type_variant mtype_variant = { .kadt = mtype_kadt, @@ -1039,6 +1206,7 @@ static const struct ip_set_type_variant mtype_variant = { .flush = mtype_flush, .head = mtype_head, .list = mtype_list, + .uref = mtype_uref, .resize = mtype_resize, .same_set = mtype_same_set, }; @@ -1076,12 +1244,14 @@ IPSET_TOKEN(HTYPE, _create)(struct net *net, struct ip_set *set, if (unlikely(!ip_set_optattr_netorder(tb, IPSET_ATTR_HASHSIZE) || !ip_set_optattr_netorder(tb, IPSET_ATTR_MAXELEM) || -#ifdef IP_SET_HASH_WITH_MARKMASK - !ip_set_optattr_netorder(tb, IPSET_ATTR_MARKMASK) || -#endif !ip_set_optattr_netorder(tb, IPSET_ATTR_TIMEOUT) || !ip_set_optattr_netorder(tb, IPSET_ATTR_CADT_FLAGS))) return -IPSET_ERR_PROTOCOL; +#ifdef IP_SET_HASH_WITH_MARKMASK + /* Separated condition in order to avoid directive in argument list */ + if (unlikely(!ip_set_optattr_netorder(tb, IPSET_ATTR_MARKMASK))) + return -IPSET_ERR_PROTOCOL; +#endif if (tb[IPSET_ATTR_HASHSIZE]) { hashsize = ip_set_get_h32(tb[IPSET_ATTR_HASHSIZE]); @@ -1104,7 +1274,7 @@ IPSET_TOKEN(HTYPE, _create)(struct net *net, struct ip_set *set, #endif #ifdef IP_SET_HASH_WITH_MARKMASK if (tb[IPSET_ATTR_MARKMASK]) { - markmask = ntohl(nla_get_u32(tb[IPSET_ATTR_MARKMASK])); + markmask = ntohl(nla_get_be32(tb[IPSET_ATTR_MARKMASK])); if (markmask == 0) return -IPSET_ERR_INVALID_MARKMASK; |