From 3ab02db5f836ae0cf9fe7fba616d7eb52139d537 Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso Date: Tue, 23 Jul 2019 15:03:23 +0200 Subject: cache: add NFT_CACHE_UPDATE and NFT_CACHE_FLUSHED flags NFT_CACHE_FLUSHED tells cache_update() to skip the netlink dump to populate the cache, since the existing ruleset is going to flushed by this batch. NFT_CACHE_UPDATE tells rule_evaluate() to perform incremental updates to the cache based on the existing batch, this is required by the rule commands that use the index and the position selectors. This patch removes cache_flush() which is not required anymore. This cache removal is coming too late, in the evaluation phase, after the initial cache_update() invocation. Be careful with NFT_CACHE_UPDATE, this flag needs to be left in place if NFT_CACHE_FLUSHED is set on. Signed-off-by: Pablo Neira Ayuso --- src/cache.c | 4 +++- src/evaluate.c | 8 +++----- src/rule.c | 33 ++++++++++++++++----------------- 3 files changed, 22 insertions(+), 23 deletions(-) (limited to 'src') diff --git a/src/cache.c b/src/cache.c index e04ead85..0d38034e 100644 --- a/src/cache.c +++ b/src/cache.c @@ -41,7 +41,7 @@ static unsigned int evaluate_cache_add(struct cmd *cmd, unsigned int flags) if (cmd->handle.index.id || cmd->handle.position.id) - flags |= NFT_CACHE_RULE; + flags |= NFT_CACHE_RULE | NFT_CACHE_UPDATE; break; default: break; @@ -72,6 +72,8 @@ static unsigned int evaluate_cache_flush(struct cmd *cmd, unsigned int flags) flags |= NFT_CACHE_SET; break; case CMD_OBJ_RULESET: + flags |= NFT_CACHE_FLUSHED; + break; default: flags = NFT_CACHE_EMPTY; break; diff --git a/src/evaluate.c b/src/evaluate.c index e7f16ba6..48c65cd2 100644 --- a/src/evaluate.c +++ b/src/evaluate.c @@ -3394,11 +3394,10 @@ static int rule_evaluate(struct eval_ctx *ctx, struct rule *rule, return -1; } - /* add rules to cache only if it is complete enough to contain them */ - if (!cache_is_complete(&ctx->nft->cache, NFT_CACHE_RULE)) - return 0; + if (cache_needs_update(&ctx->nft->cache)) + return rule_cache_update(ctx, op); - return rule_cache_update(ctx, op); + return 0; } static uint32_t str2hooknum(uint32_t family, const char *hook) @@ -3824,7 +3823,6 @@ static int cmd_evaluate_flush(struct eval_ctx *ctx, struct cmd *cmd) switch (cmd->obj) { case CMD_OBJ_RULESET: - cache_flush(ctx->nft, ctx->msgs); break; case CMD_OBJ_TABLE: /* Flushing a table does not empty the sets in the table nor remove diff --git a/src/rule.c b/src/rule.c index 0ebe91e7..29360657 100644 --- a/src/rule.c +++ b/src/rule.c @@ -224,7 +224,7 @@ static int cache_init(struct netlink_ctx *ctx, unsigned int flags) return 0; } -bool cache_is_complete(struct nft_cache *cache, unsigned int flags) +static bool cache_is_complete(struct nft_cache *cache, unsigned int flags) { return (cache->flags & flags) == flags; } @@ -234,6 +234,11 @@ static bool cache_is_updated(struct nft_cache *cache, uint16_t genid) return genid && genid == cache->genid; } +bool cache_needs_update(struct nft_cache *cache) +{ + return cache->flags & NFT_CACHE_UPDATE; +} + int cache_update(struct nft_ctx *nft, unsigned int flags, struct list_head *msgs) { struct netlink_ctx ctx = { @@ -242,7 +247,7 @@ int cache_update(struct nft_ctx *nft, unsigned int flags, struct list_head *msgs .msgs = msgs, }; struct nft_cache *cache = &nft->cache; - uint32_t genid, genid_stop; + uint32_t genid, genid_stop, oldflags; int ret; replay: ctx.seqnum = cache->seqnum++; @@ -254,6 +259,14 @@ replay: if (cache->genid) cache_release(cache); + if (flags & NFT_CACHE_FLUSHED) { + oldflags = flags; + flags = NFT_CACHE_EMPTY; + if (oldflags & NFT_CACHE_UPDATE) + flags |= NFT_CACHE_UPDATE; + goto skip; + } + ret = cache_init(&ctx, flags); if (ret < 0) { cache_release(cache); @@ -269,7 +282,7 @@ replay: cache_release(cache); goto replay; } - +skip: cache->genid = genid; cache->flags = flags; return 0; @@ -285,20 +298,6 @@ static void __cache_flush(struct list_head *table_list) } } -void cache_flush(struct nft_ctx *nft, struct list_head *msgs) -{ - struct netlink_ctx ctx = { - .list = LIST_HEAD_INIT(ctx.list), - .nft = nft, - .msgs = msgs, - }; - struct nft_cache *cache = &nft->cache; - - __cache_flush(&cache->list); - cache->genid = mnl_genid_get(&ctx); - cache->flags = NFT_CACHE_FULL; -} - void cache_release(struct nft_cache *cache) { __cache_flush(&cache->list); -- cgit v1.2.3