diff options
Diffstat (limited to 'net/core/skbuff.c')
-rw-r--r-- | net/core/skbuff.c | 176 |
1 files changed, 167 insertions, 9 deletions
diff --git a/net/core/skbuff.c b/net/core/skbuff.c index 6d68c03bc05..d9f7b06fe88 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -129,7 +129,7 @@ void skb_under_panic(struct sk_buff *skb, int sz, void *here) * Buffers may only be allocated from interrupts using a @gfp_mask of * %GFP_ATOMIC. */ -struct sk_buff *alloc_skb(unsigned int size, int gfp_mask) +struct sk_buff *alloc_skb(unsigned int size, unsigned int __nocast gfp_mask) { struct sk_buff *skb; u8 *data; @@ -182,7 +182,8 @@ nodata: * %GFP_ATOMIC. */ struct sk_buff *alloc_skb_from_cache(kmem_cache_t *cp, - unsigned int size, int gfp_mask) + unsigned int size, + unsigned int __nocast gfp_mask) { struct sk_buff *skb; u8 *data; @@ -322,7 +323,7 @@ void __kfree_skb(struct sk_buff *skb) * %GFP_ATOMIC. */ -struct sk_buff *skb_clone(struct sk_buff *skb, int gfp_mask) +struct sk_buff *skb_clone(struct sk_buff *skb, unsigned int __nocast gfp_mask) { struct sk_buff *n = kmem_cache_alloc(skbuff_head_cache, gfp_mask); @@ -357,7 +358,6 @@ struct sk_buff *skb_clone(struct sk_buff *skb, int gfp_mask) C(ip_summed); C(priority); C(protocol); - C(security); n->destructor = NULL; #ifdef CONFIG_NETFILTER C(nfmark); @@ -422,7 +422,6 @@ static void copy_skb_header(struct sk_buff *new, const struct sk_buff *old) new->pkt_type = old->pkt_type; new->stamp = old->stamp; new->destructor = NULL; - new->security = old->security; #ifdef CONFIG_NETFILTER new->nfmark = old->nfmark; new->nfcache = old->nfcache; @@ -462,7 +461,7 @@ static void copy_skb_header(struct sk_buff *new, const struct sk_buff *old) * header is going to be modified. Use pskb_copy() instead. */ -struct sk_buff *skb_copy(const struct sk_buff *skb, int gfp_mask) +struct sk_buff *skb_copy(const struct sk_buff *skb, unsigned int __nocast gfp_mask) { int headerlen = skb->data - skb->head; /* @@ -501,7 +500,7 @@ struct sk_buff *skb_copy(const struct sk_buff *skb, int gfp_mask) * The returned buffer has a reference count of 1. */ -struct sk_buff *pskb_copy(struct sk_buff *skb, int gfp_mask) +struct sk_buff *pskb_copy(struct sk_buff *skb, unsigned int __nocast gfp_mask) { /* * Allocate the copy buffer @@ -559,7 +558,8 @@ out: * reloaded after call to this function. */ -int pskb_expand_head(struct sk_buff *skb, int nhead, int ntail, int gfp_mask) +int pskb_expand_head(struct sk_buff *skb, int nhead, int ntail, + unsigned int __nocast gfp_mask) { int i; u8 *data; @@ -649,7 +649,8 @@ struct sk_buff *skb_realloc_headroom(struct sk_buff *skb, unsigned int headroom) * only by netfilter in the cases when checksum is recalculated? --ANK */ struct sk_buff *skb_copy_expand(const struct sk_buff *skb, - int newheadroom, int newtailroom, int gfp_mask) + int newheadroom, int newtailroom, + unsigned int __nocast gfp_mask) { /* * Allocate the copy buffer @@ -1500,6 +1501,159 @@ void skb_split(struct sk_buff *skb, struct sk_buff *skb1, const u32 len) skb_split_no_header(skb, skb1, len, pos); } +/** + * skb_prepare_seq_read - Prepare a sequential read of skb data + * @skb: the buffer to read + * @from: lower offset of data to be read + * @to: upper offset of data to be read + * @st: state variable + * + * Initializes the specified state variable. Must be called before + * invoking skb_seq_read() for the first time. + */ +void skb_prepare_seq_read(struct sk_buff *skb, unsigned int from, + unsigned int to, struct skb_seq_state *st) +{ + st->lower_offset = from; + st->upper_offset = to; + st->root_skb = st->cur_skb = skb; + st->frag_idx = st->stepped_offset = 0; + st->frag_data = NULL; +} + +/** + * skb_seq_read - Sequentially read skb data + * @consumed: number of bytes consumed by the caller so far + * @data: destination pointer for data to be returned + * @st: state variable + * + * Reads a block of skb data at &consumed relative to the + * lower offset specified to skb_prepare_seq_read(). Assigns + * the head of the data block to &data and returns the length + * of the block or 0 if the end of the skb data or the upper + * offset has been reached. + * + * The caller is not required to consume all of the data + * returned, i.e. &consumed is typically set to the number + * of bytes already consumed and the next call to + * skb_seq_read() will return the remaining part of the block. + * + * Note: The size of each block of data returned can be arbitary, + * this limitation is the cost for zerocopy seqeuental + * reads of potentially non linear data. + * + * Note: Fragment lists within fragments are not implemented + * at the moment, state->root_skb could be replaced with + * a stack for this purpose. + */ +unsigned int skb_seq_read(unsigned int consumed, const u8 **data, + struct skb_seq_state *st) +{ + unsigned int block_limit, abs_offset = consumed + st->lower_offset; + skb_frag_t *frag; + + if (unlikely(abs_offset >= st->upper_offset)) + return 0; + +next_skb: + block_limit = skb_headlen(st->cur_skb); + + if (abs_offset < block_limit) { + *data = st->cur_skb->data + abs_offset; + return block_limit - abs_offset; + } + + if (st->frag_idx == 0 && !st->frag_data) + st->stepped_offset += skb_headlen(st->cur_skb); + + while (st->frag_idx < skb_shinfo(st->cur_skb)->nr_frags) { + frag = &skb_shinfo(st->cur_skb)->frags[st->frag_idx]; + block_limit = frag->size + st->stepped_offset; + + if (abs_offset < block_limit) { + if (!st->frag_data) + st->frag_data = kmap_skb_frag(frag); + + *data = (u8 *) st->frag_data + frag->page_offset + + (abs_offset - st->stepped_offset); + + return block_limit - abs_offset; + } + + if (st->frag_data) { + kunmap_skb_frag(st->frag_data); + st->frag_data = NULL; + } + + st->frag_idx++; + st->stepped_offset += frag->size; + } + + if (st->cur_skb->next) { + st->cur_skb = st->cur_skb->next; + st->frag_idx = 0; + goto next_skb; + } else if (st->root_skb == st->cur_skb && + skb_shinfo(st->root_skb)->frag_list) { + st->cur_skb = skb_shinfo(st->root_skb)->frag_list; + goto next_skb; + } + + return 0; +} + +/** + * skb_abort_seq_read - Abort a sequential read of skb data + * @st: state variable + * + * Must be called if skb_seq_read() was not called until it + * returned 0. + */ +void skb_abort_seq_read(struct skb_seq_state *st) +{ + if (st->frag_data) + kunmap_skb_frag(st->frag_data); +} + +#define TS_SKB_CB(state) ((struct skb_seq_state *) &((state)->cb)) + +static unsigned int skb_ts_get_next_block(unsigned int offset, const u8 **text, + struct ts_config *conf, + struct ts_state *state) +{ + return skb_seq_read(offset, text, TS_SKB_CB(state)); +} + +static void skb_ts_finish(struct ts_config *conf, struct ts_state *state) +{ + skb_abort_seq_read(TS_SKB_CB(state)); +} + +/** + * skb_find_text - Find a text pattern in skb data + * @skb: the buffer to look in + * @from: search offset + * @to: search limit + * @config: textsearch configuration + * @state: uninitialized textsearch state variable + * + * Finds a pattern in the skb data according to the specified + * textsearch configuration. Use textsearch_next() to retrieve + * subsequent occurrences of the pattern. Returns the offset + * to the first occurrence or UINT_MAX if no match was found. + */ +unsigned int skb_find_text(struct sk_buff *skb, unsigned int from, + unsigned int to, struct ts_config *config, + struct ts_state *state) +{ + config->get_next_block = skb_ts_get_next_block; + config->finish = skb_ts_finish; + + skb_prepare_seq_read(skb, from, to, TS_SKB_CB(state)); + + return textsearch_find(config, state); +} + void __init skb_init(void) { skbuff_head_cache = kmem_cache_create("skbuff_head_cache", @@ -1538,3 +1692,7 @@ EXPORT_SYMBOL(skb_queue_tail); EXPORT_SYMBOL(skb_unlink); EXPORT_SYMBOL(skb_append); EXPORT_SYMBOL(skb_split); +EXPORT_SYMBOL(skb_prepare_seq_read); +EXPORT_SYMBOL(skb_seq_read); +EXPORT_SYMBOL(skb_abort_seq_read); +EXPORT_SYMBOL(skb_find_text); |