]>
git.ipfire.org Git - thirdparty/bird.git/blob - nest/rt-attr.c
edf27d4457e30d4d1efd9da02d1f9feee12f74bb
2 * BIRD -- Route Attribute Cache
4 * (c) 1998--2000 Martin Mares <mj@ucw.cz>
6 * Can be freely distributed and used under the terms of the GNU GPL.
10 * DOC: Route attribute cache
12 * Each route entry carries a set of route attributes. Several of them
13 * vary from route to route, but most attributes are usually common
14 * for a large number of routes. To conserve memory, we've decided to
15 * store only the varying ones directly in the &rte and hold the rest
16 * in a special structure called &rta which is shared among all the
17 * &rte's with these attributes.
19 * Each &rta contains all the static attributes of the route (i.e.,
20 * those which are always present) as structure members and a list of
21 * dynamic attributes represented by a linked list of &ea_list
22 * structures, each of them consisting of an array of &eattr's containing
23 * the individual attributes. An attribute can be specified more than once
24 * in the &ea_list chain and in such case the first occurrence overrides
25 * the others. This semantics is used especially when someone (for example
26 * a filter) wishes to alter values of several dynamic attributes, but
27 * it wants to preserve the original attribute lists maintained by
30 * Each &eattr contains an attribute identifier (split to protocol ID and
31 * per-protocol attribute ID), protocol dependent flags, a type code (consisting
32 * of several bit fields describing attribute characteristics) and either an
33 * embedded 32-bit value or a pointer to a &adata structure holding attribute
36 * There exist two variants of &rta's -- cached and un-cached ones. Un-cached
37 * &rta's can have arbitrarily complex structure of &ea_list's and they
38 * can be modified by any module in the route processing chain. Cached
39 * &rta's have their attribute lists normalized (that means at most one
40 * &ea_list is present and its values are sorted in order to speed up
41 * searching), they are stored in a hash table to make fast lookup possible
42 * and they are provided with a use count to allow sharing.
44 * Routing tables always contain only cached &rta's.
47 #include "nest/bird.h"
48 #include "nest/route.h"
49 #include "nest/protocol.h"
50 #include "nest/iface.h"
52 #include "nest/attrs.h"
53 #include "lib/alloca.h"
55 #include "lib/resource.h"
56 #include "lib/string.h"
60 static slab
*rta_slab
;
61 static slab
*mpnh_slab
;
62 static slab
*rte_src_slab
;
64 /* rte source ID bitmap */
66 static u32 src_id_size
, src_id_used
, src_id_pos
;
67 #define SRC_ID_INIT_SIZE 4
71 #define RSH_KEY(n) n->proto, n->private_id
72 #define RSH_NEXT(n) n->next
73 #define RSH_EQ(p1,n1,p2,n2) p1 == p2 && n1 == n2
74 #define RSH_FN(p,n) p->hash_key ^ u32_hash(n)
76 #define RSH_REHASH rte_src_rehash
77 #define RSH_PARAMS /2, *2, 1, 1, 8, 20
78 #define RSH_INIT_ORDER 6
80 static HASH(struct rte_src
) src_hash
;
82 struct protocol
*attr_class_to_protocol
[EAP_MAX
];
88 rte_src_slab
= sl_new(rta_pool
, sizeof(struct rte_src
));
91 src_id_size
= SRC_ID_INIT_SIZE
;
92 src_ids
= mb_allocz(rta_pool
, src_id_size
* sizeof(u32
));
94 /* ID 0 is reserved */
98 HASH_INIT(src_hash
, rta_pool
, RSH_INIT_ORDER
);
101 static inline int u32_cto(uint x
) { return ffs(~x
) - 1; }
104 rte_src_alloc_id(void)
107 for (i
= src_id_pos
; i
< src_id_size
; i
++)
108 if (src_ids
[i
] != 0xffffffff)
111 /* If we are at least 7/8 full, expand */
112 if (src_id_used
> (src_id_size
* 28))
115 src_ids
= mb_realloc(src_ids
, src_id_size
* sizeof(u32
));
116 bzero(src_ids
+ i
, (src_id_size
- i
) * sizeof(u32
));
120 for (i
= 0; i
< src_id_pos
; i
++)
121 if (src_ids
[i
] != 0xffffffff)
127 ASSERT(i
< 0x8000000);
130 j
= u32_cto(src_ids
[i
]);
132 src_ids
[i
] |= (1 << j
);
138 rte_src_free_id(u32 id
)
143 ASSERT((i
< src_id_size
) && (src_ids
[i
] & (1 << j
)));
144 src_ids
[i
] &= ~(1 << j
);
149 HASH_DEFINE_REHASH_FN(RSH
, struct rte_src
)
152 rt_find_source(struct proto
*p
, u32 id
)
154 return HASH_FIND(src_hash
, RSH
, p
, id
);
158 rt_get_source(struct proto
*p
, u32 id
)
160 struct rte_src
*src
= rt_find_source(p
, id
);
165 src
= sl_alloc(rte_src_slab
);
167 src
->private_id
= id
;
168 src
->global_id
= rte_src_alloc_id();
171 HASH_INSERT2(src_hash
, RSH
, rta_pool
, src
);
177 rt_prune_sources(void)
179 HASH_WALK_FILTER(src_hash
, next
, src
, sp
)
183 HASH_DO_REMOVE(src_hash
, RSH
, sp
);
184 rte_src_free_id(src
->global_id
);
185 sl_free(rte_src_slab
, src
);
188 HASH_WALK_FILTER_END
;
190 HASH_MAY_RESIZE_DOWN(src_hash
, RSH
, rta_pool
);
199 mpnh_hash(struct mpnh
*x
)
202 for (; x
; x
= x
->next
)
203 h
^= ipa_hash(x
->gw
);
209 mpnh__same(struct mpnh
*x
, struct mpnh
*y
)
211 for (; x
&& y
; x
= x
->next
, y
= y
->next
)
212 if (!ipa_equal(x
->gw
, y
->gw
) || (x
->iface
!= y
->iface
) || (x
->weight
!= y
->weight
))
219 mpnh_compare_node(struct mpnh
*x
, struct mpnh
*y
)
229 r
= ((int) y
->weight
) - ((int) x
->weight
);
233 r
= ipa_compare(x
->gw
, y
->gw
);
237 return ((int) x
->iface
->index
) - ((int) y
->iface
->index
);
240 static inline struct mpnh
*
241 mpnh_copy_node(const struct mpnh
*src
, linpool
*lp
)
243 struct mpnh
*n
= lp_alloc(lp
, sizeof(struct mpnh
));
245 n
->iface
= src
->iface
;
247 n
->weight
= src
->weight
;
252 * mpnh_merge - merge nexthop lists
255 * @rx: reusability of list @x
256 * @ry: reusability of list @y
257 * @max: max number of nexthops
258 * @lp: linpool for allocating nexthops
260 * The mpnh_merge() function takes two nexthop lists @x and @y and merges them,
261 * eliminating possible duplicates. The input lists must be sorted and the
262 * result is sorted too. The number of nexthops in result is limited by @max.
263 * New nodes are allocated from linpool @lp.
265 * The arguments @rx and @ry specify whether corresponding input lists may be
266 * consumed by the function (i.e. their nodes reused in the resulting list), in
267 * that case the caller should not access these lists after that. To eliminate
268 * issues with deallocation of these lists, the caller should use some form of
269 * bulk deallocation (e.g. stack or linpool) to free these nodes when the
270 * resulting list is no longer needed. When reusability is not set, the
271 * corresponding lists are not modified nor linked from the resulting list.
274 mpnh_merge(struct mpnh
*x
, struct mpnh
*y
, int rx
, int ry
, int max
, linpool
*lp
)
276 struct mpnh
*root
= NULL
;
277 struct mpnh
**n
= &root
;
279 while ((x
|| y
) && max
--)
281 int cmp
= mpnh_compare_node(x
, y
);
284 *n
= rx
? x
: mpnh_copy_node(x
, lp
);
289 *n
= ry
? y
: mpnh_copy_node(y
, lp
);
294 *n
= rx
? x
: (ry
? y
: mpnh_copy_node(x
, lp
));
306 mpnh_insert(struct mpnh
**n
, struct mpnh
*x
)
308 for (; *n
; n
= &((*n
)->next
))
310 int cmp
= mpnh_compare_node(*n
, x
);
325 mpnh_is_sorted(struct mpnh
*x
)
327 for (; x
&& x
->next
; x
= x
->next
)
328 if (mpnh_compare_node(x
, x
->next
) >= 0)
335 mpnh_copy(struct mpnh
*o
)
337 struct mpnh
*first
= NULL
;
338 struct mpnh
**last
= &first
;
340 for (; o
; o
= o
->next
)
342 struct mpnh
*n
= sl_alloc(mpnh_slab
);
346 n
->weight
= o
->weight
;
356 mpnh_free(struct mpnh
*o
)
363 sl_free(mpnh_slab
, o
);
370 * Extended Attributes
373 static inline eattr
*
374 ea__find(ea_list
*e
, unsigned id
)
381 if (e
->flags
& EALF_BISECT
)
398 for(m
=0; m
<e
->count
; m
++)
399 if (e
->attrs
[m
].id
== id
)
407 * ea_find - find an extended attribute
408 * @e: attribute list to search in
409 * @id: attribute ID to search for
411 * Given an extended attribute list, ea_find() searches for a first
412 * occurrence of an attribute with specified ID, returning either a pointer
413 * to its &eattr structure or %NULL if no such attribute exists.
416 ea_find(ea_list
*e
, unsigned id
)
418 eattr
*a
= ea__find(e
, id
& EA_CODE_MASK
);
420 if (a
&& (a
->type
& EAF_TYPE_MASK
) == EAF_TYPE_UNDEF
&&
421 !(id
& EA_ALLOW_UNDEF
))
427 * ea_walk - walk through extended attributes
428 * @s: walk state structure
429 * @id: start of attribute ID interval
430 * @max: length of attribute ID interval
432 * Given an extended attribute list, ea_walk() walks through the list looking
433 * for first occurrences of attributes with ID in specified interval from @id to
434 * (@id + @max - 1), returning pointers to found &eattr structures, storing its
435 * walk state in @s for subsequent calls.
437 * The function ea_walk() is supposed to be called in a loop, with initially
438 * zeroed walk state structure @s with filled the initial extended attribute
439 * list, returning one found attribute in each call or %NULL when no other
440 * attribute exists. The extended attribute list or the arguments should not be
441 * modified between calls. The maximum value of @max is 128.
444 ea_walk(struct ea_walk_state
*s
, uint id
, uint max
)
446 ea_list
*e
= s
->eattrs
;
455 for (; e
; e
= e
->next
)
457 if (e
->flags
& EALF_BISECT
)
466 if (e
->attrs
[m
].id
< id
)
477 a_max
= e
->attrs
+ e
->count
;
478 for (; a
< a_max
; a
++)
479 if ((a
->id
>= id
) && (a
->id
< max
))
483 if (BIT32_TEST(s
->visited
, n
))
486 BIT32_SET(s
->visited
, n
);
488 if ((a
->type
& EAF_TYPE_MASK
) == EAF_TYPE_UNDEF
)
495 else if (e
->flags
& EALF_BISECT
)
503 * ea_get_int - fetch an integer attribute
506 * @def: default value
508 * This function is a shortcut for retrieving a value of an integer attribute
509 * by calling ea_find() to find the attribute, extracting its value or returning
510 * a provided default if no such attribute is present.
513 ea_get_int(ea_list
*e
, unsigned id
, int def
)
515 eattr
*a
= ea_find(e
, id
);
522 ea_do_sort(ea_list
*e
)
524 unsigned n
= e
->count
;
526 eattr
*b
= alloca(n
* sizeof(eattr
));
529 /* We need to use a stable sorting algorithm, hence mergesort */
535 eattr
*p
, *q
, *lo
, *hi
;
539 while (s
< n
&& p
[-1].id
<= a
[s
].id
)
545 while (s
< n
&& p
[-1].id
<= a
[s
].id
)
550 while (lo
< q
&& hi
< p
)
551 if (lo
->id
<= hi
->id
)
566 ea_do_prune(ea_list
*e
)
568 eattr
*s
, *d
, *l
, *s0
;
571 /* Discard duplicates and undefs. Do you remember sorting was stable? */
573 l
= e
->attrs
+ e
->count
;
577 while (s
< l
&& s
->id
== s
[-1].id
)
579 /* s0 is the most recent version, s[-1] the oldest one */
580 if ((s0
->type
& EAF_TYPE_MASK
) != EAF_TYPE_UNDEF
)
583 d
->type
= (d
->type
& ~EAF_ORIGINATED
) | (s
[-1].type
& EAF_ORIGINATED
);
592 * ea_sort - sort an attribute list
593 * @e: list to be sorted
595 * This function takes a &ea_list chain and sorts the attributes
596 * within each of its entries.
598 * If an attribute occurs multiple times in a single &ea_list,
599 * ea_sort() leaves only the first (the only significant) occurrence.
606 if (!(e
->flags
& EALF_SORTED
))
610 e
->flags
|= EALF_SORTED
;
613 e
->flags
|= EALF_BISECT
;
619 * ea_scan - estimate attribute list size
622 * This function calculates an upper bound of the size of
623 * a given &ea_list after merging with ea_merge().
635 return sizeof(ea_list
) + sizeof(eattr
)*cnt
;
639 * ea_merge - merge segments of an attribute list
641 * @t: buffer to store the result to
643 * This function takes a possibly multi-segment attribute list
644 * and merges all of its segments to one.
646 * The primary use of this function is for &ea_list normalization:
647 * first call ea_scan() to determine how much memory will the result
648 * take, then allocate a buffer (usually using alloca()), merge the
649 * segments with ea_merge() and finally sort and prune the result
650 * by calling ea_sort().
653 ea_merge(ea_list
*e
, ea_list
*t
)
662 memcpy(d
, e
->attrs
, sizeof(eattr
)*e
->count
);
663 t
->count
+= e
->count
;
670 * ea_same - compare two &ea_list's
674 * ea_same() compares two normalized attribute lists @x and @y and returns
675 * 1 if they contain the same attributes, 0 otherwise.
678 ea_same(ea_list
*x
, ea_list
*y
)
684 ASSERT(!x
->next
&& !y
->next
);
685 if (x
->count
!= y
->count
)
687 for(c
=0; c
<x
->count
; c
++)
689 eattr
*a
= &x
->attrs
[c
];
690 eattr
*b
= &y
->attrs
[c
];
692 if (a
->id
!= b
->id
||
693 a
->flags
!= b
->flags
||
694 a
->type
!= b
->type
||
695 ((a
->type
& EAF_EMBEDDED
) ? a
->u
.data
!= b
->u
.data
: !adata_same(a
->u
.ptr
, b
->u
.ptr
)))
701 static inline ea_list
*
702 ea_list_copy(ea_list
*o
)
710 len
= sizeof(ea_list
) + sizeof(eattr
) * o
->count
;
711 n
= mb_alloc(rta_pool
, len
);
713 n
->flags
|= EALF_CACHED
;
714 for(i
=0; i
<o
->count
; i
++)
716 eattr
*a
= &n
->attrs
[i
];
717 if (!(a
->type
& EAF_EMBEDDED
))
719 unsigned size
= sizeof(struct adata
) + a
->u
.ptr
->length
;
720 struct adata
*d
= mb_alloc(rta_pool
, size
);
721 memcpy(d
, a
->u
.ptr
, size
);
736 for(i
=0; i
<o
->count
; i
++)
738 eattr
*a
= &o
->attrs
[i
];
739 if (!(a
->type
& EAF_EMBEDDED
))
747 get_generic_attr(eattr
*a
, byte
**buf
, int buflen UNUSED
)
749 if (a
->id
== EA_GEN_IGP_METRIC
)
751 *buf
+= bsprintf(*buf
, "igp_metric");
759 ea_format_bitfield(struct eattr
*a
, byte
*buf
, int bufsize
, const char **names
, int min
, int max
)
761 byte
*bound
= buf
+ bufsize
- 32;
762 u32 data
= a
->u
.data
;
765 for (i
= min
; i
< max
; i
++)
766 if ((data
& (1u << i
)) && names
[i
])
774 buf
+= bsprintf(buf
, " %s", names
[i
]);
779 bsprintf(buf
, " %08x", data
);
785 opaque_format(struct adata
*ad
, byte
*buf
, uint size
)
787 byte
*bound
= buf
+ size
- 10;
790 for(i
= 0; i
< ad
->length
; i
++)
800 buf
+= bsprintf(buf
, "%02x", ad
->data
[i
]);
808 ea_show_int_set(struct cli
*c
, struct adata
*ad
, int way
, byte
*pos
, byte
*buf
, byte
*end
)
810 int i
= int_set_format(ad
, way
, 0, pos
, end
- pos
);
811 cli_printf(c
, -1012, "\t%s", buf
);
814 i
= int_set_format(ad
, way
, i
, buf
, end
- buf
- 1);
815 cli_printf(c
, -1012, "\t\t%s", buf
);
820 ea_show_ec_set(struct cli
*c
, struct adata
*ad
, byte
*pos
, byte
*buf
, byte
*end
)
822 int i
= ec_set_format(ad
, 0, pos
, end
- pos
);
823 cli_printf(c
, -1012, "\t%s", buf
);
826 i
= ec_set_format(ad
, i
, buf
, end
- buf
- 1);
827 cli_printf(c
, -1012, "\t\t%s", buf
);
832 ea_show_lc_set(struct cli
*c
, struct adata
*ad
, byte
*pos
, byte
*buf
, byte
*end
)
834 int i
= lc_set_format(ad
, 0, pos
, end
- pos
);
835 cli_printf(c
, -1012, "\t%s", buf
);
838 i
= lc_set_format(ad
, i
, buf
, end
- buf
- 1);
839 cli_printf(c
, -1012, "\t\t%s", buf
);
844 * ea_show - print an &eattr to CLI
845 * @c: destination CLI
846 * @e: attribute to be printed
848 * This function takes an extended attribute represented by its &eattr
849 * structure and prints it to the CLI according to the type information.
851 * If the protocol defining the attribute provides its own
852 * get_attr() hook, it's consulted first.
855 ea_show(struct cli
*c
, eattr
*e
)
858 int status
= GA_UNKNOWN
;
859 struct adata
*ad
= (e
->type
& EAF_EMBEDDED
) ? NULL
: e
->u
.ptr
;
860 byte buf
[CLI_MSG_SIZE
];
861 byte
*pos
= buf
, *end
= buf
+ sizeof(buf
);
863 if (p
= attr_class_to_protocol
[EA_PROTO(e
->id
)])
865 pos
+= bsprintf(pos
, "%s.", p
->name
);
867 status
= p
->get_attr(e
, pos
, end
- pos
);
870 else if (EA_PROTO(e
->id
))
871 pos
+= bsprintf(pos
, "%02x.", EA_PROTO(e
->id
));
873 status
= get_generic_attr(e
, &pos
, end
- pos
);
875 if (status
< GA_NAME
)
876 pos
+= bsprintf(pos
, "%02x", EA_ID(e
->id
));
877 if (status
< GA_FULL
)
881 switch (e
->type
& EAF_TYPE_MASK
)
884 bsprintf(pos
, "%u", e
->u
.data
);
886 case EAF_TYPE_OPAQUE
:
887 opaque_format(ad
, pos
, end
- pos
);
889 case EAF_TYPE_IP_ADDRESS
:
890 bsprintf(pos
, "%I", *(ip_addr
*) ad
->data
);
892 case EAF_TYPE_ROUTER_ID
:
893 bsprintf(pos
, "%R", e
->u
.data
);
895 case EAF_TYPE_AS_PATH
:
896 as_path_format(ad
, pos
, end
- pos
);
898 case EAF_TYPE_BITFIELD
:
899 bsprintf(pos
, "%08x", e
->u
.data
);
901 case EAF_TYPE_INT_SET
:
902 ea_show_int_set(c
, ad
, 1, pos
, buf
, end
);
904 case EAF_TYPE_EC_SET
:
905 ea_show_ec_set(c
, ad
, pos
, buf
, end
);
907 case EAF_TYPE_LC_SET
:
908 ea_show_lc_set(c
, ad
, pos
, buf
, end
);
912 bsprintf(pos
, "<type %02x>", e
->type
);
915 cli_printf(c
, -1012, "\t%s", buf
);
919 * ea_dump - dump an extended attribute
920 * @e: attribute to be dumped
922 * ea_dump() dumps contents of the extended attribute given to
938 (e
->flags
& EALF_SORTED
) ? 'S' : 's',
939 (e
->flags
& EALF_BISECT
) ? 'B' : 'b',
940 (e
->flags
& EALF_CACHED
) ? 'C' : 'c');
941 for(i
=0; i
<e
->count
; i
++)
943 eattr
*a
= &e
->attrs
[i
];
944 debug(" %02x:%02x.%02x", EA_PROTO(a
->id
), EA_ID(a
->id
), a
->flags
);
945 if (a
->type
& EAF_TEMP
)
947 debug("=%c", "?iO?I?P???S?????" [a
->type
& EAF_TYPE_MASK
]);
948 if (a
->type
& EAF_ORIGINATED
)
950 if (a
->type
& EAF_EMBEDDED
)
951 debug(":%08x", a
->u
.data
);
954 int j
, len
= a
->u
.ptr
->length
;
957 debug("%02x", a
->u
.ptr
->data
[j
]);
966 * ea_hash - calculate an &ea_list hash key
969 * ea_hash() takes an extended attribute list and calculated a hopefully
970 * uniformly distributed hash value from its contents.
978 if (e
) /* Assuming chain of length 1 */
980 for(i
=0; i
<e
->count
; i
++)
982 struct eattr
*a
= &e
->attrs
[i
];
984 if (a
->type
& EAF_EMBEDDED
)
988 struct adata
*d
= a
->u
.ptr
;
989 int size
= d
->length
;
998 h
= (h
>> 24) ^ (h
<< 8) ^ *z
++;
1009 * ea_append - concatenate &ea_list's
1010 * @to: destination list (can be %NULL)
1011 * @what: list to be appended (can be %NULL)
1013 * This function appends the &ea_list @what at the end of
1014 * &ea_list @to and returns a pointer to the resulting list.
1017 ea_append(ea_list
*to
, ea_list
*what
)
1034 static uint rta_cache_count
;
1035 static uint rta_cache_size
= 32;
1036 static uint rta_cache_limit
;
1037 static uint rta_cache_mask
;
1038 static rta
**rta_hash_table
;
1041 rta_alloc_hash(void)
1043 rta_hash_table
= mb_allocz(rta_pool
, sizeof(rta
*) * rta_cache_size
);
1044 if (rta_cache_size
< 32768)
1045 rta_cache_limit
= rta_cache_size
* 2;
1047 rta_cache_limit
= ~0;
1048 rta_cache_mask
= rta_cache_size
- 1;
1054 return (((uint
) (uintptr_t) a
->src
) ^ ipa_hash(a
->gw
) ^
1055 mpnh_hash(a
->nexthops
) ^ ea_hash(a
->eattrs
)) & 0xffff;
1059 rta_same(rta
*x
, rta
*y
)
1061 return (x
->src
== y
->src
&&
1062 x
->source
== y
->source
&&
1063 x
->scope
== y
->scope
&&
1064 x
->cast
== y
->cast
&&
1065 x
->dest
== y
->dest
&&
1066 x
->flags
== y
->flags
&&
1067 x
->igp_metric
== y
->igp_metric
&&
1068 ipa_equal(x
->gw
, y
->gw
) &&
1069 ipa_equal(x
->from
, y
->from
) &&
1070 x
->iface
== y
->iface
&&
1071 x
->hostentry
== y
->hostentry
&&
1072 mpnh_same(x
->nexthops
, y
->nexthops
) &&
1073 ea_same(x
->eattrs
, y
->eattrs
));
1079 rta
*r
= sl_alloc(rta_slab
);
1081 memcpy(r
, o
, sizeof(rta
));
1083 r
->nexthops
= mpnh_copy(o
->nexthops
);
1084 r
->eattrs
= ea_list_copy(o
->eattrs
);
1091 uint h
= r
->hash_key
& rta_cache_mask
;
1092 r
->next
= rta_hash_table
[h
];
1094 r
->next
->pprev
= &r
->next
;
1095 r
->pprev
= &rta_hash_table
[h
];
1096 rta_hash_table
[h
] = r
;
1102 uint ohs
= rta_cache_size
;
1105 rta
**oht
= rta_hash_table
;
1107 rta_cache_size
= 2*rta_cache_size
;
1108 DBG("Rehashing rta cache from %d to %d entries.\n", ohs
, rta_cache_size
);
1110 for(h
=0; h
<ohs
; h
++)
1111 for(r
=oht
[h
]; r
; r
=n
)
1120 * rta_lookup - look up a &rta in attribute cache
1121 * @o: a un-cached &rta
1123 * rta_lookup() gets an un-cached &rta structure and returns its cached
1124 * counterpart. It starts with examining the attribute cache to see whether
1125 * there exists a matching entry. If such an entry exists, it's returned and
1126 * its use count is incremented, else a new entry is created with use count
1129 * The extended attribute lists attached to the &rta are automatically
1130 * converted to the normalized form.
1138 ASSERT(!(o
->aflags
& RTAF_CACHED
));
1141 if (o
->eattrs
->next
) /* Multiple ea_list's, need to merge them */
1143 ea_list
*ml
= alloca(ea_scan(o
->eattrs
));
1144 ea_merge(o
->eattrs
, ml
);
1151 for(r
=rta_hash_table
[h
& rta_cache_mask
]; r
; r
=r
->next
)
1152 if (r
->hash_key
== h
&& rta_same(r
, o
))
1153 return rta_clone(r
);
1157 r
->aflags
= RTAF_CACHED
;
1158 rt_lock_source(r
->src
);
1159 rt_lock_hostentry(r
->hostentry
);
1162 if (++rta_cache_count
> rta_cache_limit
)
1171 ASSERT(rta_cache_count
&& (a
->aflags
& RTAF_CACHED
));
1173 *a
->pprev
= a
->next
;
1175 a
->next
->pprev
= a
->pprev
;
1176 a
->aflags
= 0; /* Poison the entry */
1177 rt_unlock_hostentry(a
->hostentry
);
1178 rt_unlock_source(a
->src
);
1179 mpnh_free(a
->nexthops
);
1181 sl_free(rta_slab
, a
);
1185 rta_do_cow(rta
*o
, linpool
*lp
)
1187 rta
*r
= lp_alloc(lp
, sizeof(rta
));
1188 memcpy(r
, o
, sizeof(rta
));
1195 * rta_dump - dump route attributes
1196 * @a: attribute structure to dump
1198 * This function takes a &rta and dumps its contents to the debug output.
1203 static char *rts
[] = { "RTS_DUMMY", "RTS_STATIC", "RTS_INHERIT", "RTS_DEVICE",
1204 "RTS_STAT_DEV", "RTS_REDIR", "RTS_RIP",
1205 "RTS_OSPF", "RTS_OSPF_IA", "RTS_OSPF_EXT1",
1206 "RTS_OSPF_EXT2", "RTS_BGP", "RTS_PIPE", "RTS_BABEL" };
1207 static char *rtc
[] = { "", " BC", " MC", " AC" };
1208 static char *rtd
[] = { "", " DEV", " HOLE", " UNREACH", " PROHIBIT" };
1210 debug("p=%s uc=%d %s %s%s%s h=%04x",
1211 a
->src
->proto
->name
, a
->uc
, rts
[a
->source
], ip_scope_text(a
->scope
), rtc
[a
->cast
],
1212 rtd
[a
->dest
], a
->hash_key
);
1213 if (!(a
->aflags
& RTAF_CACHED
))
1215 debug(" <-%I", a
->from
);
1216 if (a
->dest
== RTD_ROUTER
)
1217 debug(" ->%I", a
->gw
);
1218 if (a
->dest
== RTD_DEVICE
|| a
->dest
== RTD_ROUTER
)
1219 debug(" [%s]", a
->iface
? a
->iface
->name
: "???" );
1228 * rta_dump_all - dump attribute cache
1230 * This function dumps the whole contents of route attribute cache
1231 * to the debug output.
1239 debug("Route attribute cache (%d entries, rehash at %d):\n", rta_cache_count
, rta_cache_limit
);
1240 for(h
=0; h
<rta_cache_size
; h
++)
1241 for(a
=rta_hash_table
[h
]; a
; a
=a
->next
)
1251 rta_show(struct cli
*c
, rta
*a
, ea_list
*eal
)
1253 static char *src_names
[] = { "dummy", "static", "inherit", "device", "static-device", "redirect",
1254 "RIP", "OSPF", "OSPF-IA", "OSPF-E1", "OSPF-E2", "BGP", "pipe" };
1255 static char *cast_names
[] = { "unicast", "broadcast", "multicast", "anycast" };
1258 cli_printf(c
, -1008, "\tType: %s %s %s", src_names
[a
->source
], cast_names
[a
->cast
], ip_scope_text(a
->scope
));
1261 for(; eal
; eal
=eal
->next
)
1262 for(i
=0; i
<eal
->count
; i
++)
1263 ea_show(c
, &eal
->attrs
[i
]);
1267 * rta_init - initialize route attribute cache
1269 * This function is called during initialization of the routing
1270 * table module to set up the internals of the attribute cache.
1275 rta_pool
= rp_new(&root_pool
, "Attributes");
1276 rta_slab
= sl_new(rta_pool
, sizeof(rta
));
1277 mpnh_slab
= sl_new(rta_pool
, sizeof(struct mpnh
));
1283 * Documentation for functions declared inline in route.h
1288 * rta_clone - clone route attributes
1289 * @r: a &rta to be cloned
1291 * rta_clone() takes a cached &rta and returns its identical cached
1292 * copy. Currently it works by just returning the original &rta with
1293 * its use count incremented.
1295 static inline rta
*rta_clone(rta
*r
)
1299 * rta_free - free route attributes
1300 * @r: a &rta to be freed
1302 * If you stop using a &rta (for example when deleting a route which uses
1303 * it), you need to call rta_free() to notify the attribute cache the
1304 * attribute is no longer in use and can be freed if you were the last
1305 * user (which rta_free() tests by inspecting the use count).
1307 static inline void rta_free(rta
*r
)