/* * Copyright (c) 1998-2002 Luigi Rizzo, Universita` di Pisa * Portions Copyright (c) 2000 Akamba Corp. * All rights reserved * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * $FreeBSD: src/sys/netinet/ip_dummynet.h,v 1.10.2.9 2003/05/13 09:31:06 maxim Exp $ * $DragonFly: src/sys/net/dummynet/ip_dummynet.h,v 1.9 2007/10/25 13:13:18 sephe Exp $ */ #ifndef _IP_DUMMYNET_H #define _IP_DUMMYNET_H /* * Definition of dummynet data structures. In the structures, I decided * not to use the macros in in the hope of making the code * easier to port to other architectures. The type of lists and queue we * use here is pretty simple anyways. */ /* * We start with a heap, which is used in the scheduler to decide when * to transmit packets etc. * * The key for the heap is used for two different values: * * 1. timer ticks- max 10K/second, so 32 bits are enough; * * 2. virtual times. These increase in steps of len/x, where len is the * packet length, and x is either the weight of the flow, or the * sum of all weights. * If we limit to max 1000 flows and a max weight of 100, then * x needs 17 bits. The packet size is 16 bits, so we can easily * overflow if we do not allow errors. * So we use a key "dn_key" which is 64 bits. Some macros are used to * compare key values and handle wraparounds. * MAX64 returns the largest of two key values. * MY_M is used as a shift count when doing fixed point arithmetic * (a better name would be useful...). */ typedef uint64_t dn_key; /* sorting key */ #define DN_KEY_LT(a,b) ((int64_t)((a)-(b)) < 0) #define DN_KEY_LEQ(a,b) ((int64_t)((a)-(b)) <= 0) #define DN_KEY_GT(a,b) ((int64_t)((a)-(b)) > 0) #define DN_KEY_GEQ(a,b) ((int64_t)((a)-(b)) >= 0) #define MAX64(x,y) (((int64_t)((y) - (x))) > 0) ? (y) : (x) #define MY_M 16 /* number of left shift to obtain a larger precision */ /* * XXX With this scaling, max 1000 flows, max weight 100, 1Gbit/s, the * virtual time wraps every 15 days. */ /* * The maximum hash table size for queues. This value must be a power * of 2. */ #define DN_MAX_HASH_SIZE 65536 /* * A heap entry is made of a key and a pointer to the actual * object stored in the heap. * The heap is an array of dn_heap_entry entries, dynamically allocated. * Current size is "size", with "elements" actually in use. * The heap normally supports only ordered insert and extract from the top. * If we want to extract an object from the middle of the heap, we * have to know where the object itself is located in the heap (or we * need to scan the whole array). To this purpose, an object has a * field (int) which contains the index of the object itself into the * heap. When the object is moved, the field must also be updated. * The offset of the index in the object is stored in the 'offset' * field in the heap descriptor. The assumption is that this offset * is non-zero if we want to support extract from the middle. */ struct dn_heap_entry { dn_key key; /* sorting key. Topmost element is smallest one */ void *object; /* object pointer */ }; struct dn_heap { int size; int elements; int offset; /* XXX if > 0 this is the offset of direct ptr to obj */ struct dn_heap_entry *p; /* really an array of "size" entries */ }; #if defined(_KERNEL) || defined(_KERNEL_STRUCTURES) /* * struct dn_pkt identifies a packet in the dummynet queue, but * is also used to tag packets passed back to the various destinations * (ip_input(), ip_output() and so on). * It is a tag(PACKET_TAG_DUMMYNET) associated with the actual mbuf. */ struct dn_pkt { struct mbuf *dn_m; struct dn_pkt *dn_next; struct ip_fw *rule; /* matching rule */ int dn_dir; /* action when packet comes out. */ #define DN_TO_IP_OUT 1 #define DN_TO_IP_IN 2 #define DN_TO_ETH_DEMUX 4 #define DN_TO_ETH_OUT 5 dn_key output_time; /* when the pkt is due for delivery */ struct ifnet *ifp; /* interface, for ip_output */ struct sockaddr_in *dn_dst; struct route ro; /* route, for ip_output. MUST COPY */ int flags; /* flags, for ip_output (IPv6 ?) */ }; #endif /* * Overall structure of dummynet (with WF2Q+): * * In dummynet, packets are selected with the firewall rules, and passed * to two different objects: PIPE or QUEUE. * * A QUEUE is just a queue with configurable size and queue management * policy. It is also associated with a mask (to discriminate among * different flows), a weight (used to give different shares of the * bandwidth to different flows) and a "pipe", which essentially * supplies the transmit clock for all queues associated with that * pipe. * * A PIPE emulates a fixed-bandwidth link, whose bandwidth is * configurable. The "clock" for a pipe can come from either an * internal timer, or from the transmit interrupt of an interface. * A pipe is also associated with one (or more, if masks are used) * queue, where all packets for that pipe are stored. * * The bandwidth available on the pipe is shared by the queues * associated with that pipe (only one in case the packet is sent * to a PIPE) according to the WF2Q+ scheduling algorithm and the * configured weights. * * In general, incoming packets are stored in the appropriate queue, * which is then placed into one of a few heaps managed by a scheduler * to decide when the packet should be extracted. * The scheduler (a function called dummynet()) is run at every timer * tick, and grabs queues from the head of the heaps when they are * ready for processing. * * There are three data structures definining a pipe and associated queues: * * + dn_pipe, which contains the main configuration parameters related * to delay and bandwidth; * + dn_flow_set, which contains WF2Q+ configuration, flow * masks, plr and RED configuration; * + dn_flow_queue, which is the per-flow queue (containing the packets) * * Multiple dn_flow_set can be linked to the same pipe, and multiple * dn_flow_queue can be linked to the same dn_flow_set. * All data structures are linked in a linear list which is used for * housekeeping purposes. * * During configuration, we create and initialize the dn_flow_set * and dn_pipe structures (a dn_pipe also contains a dn_flow_set). * * At runtime: packets are sent to the appropriate dn_flow_set (either * WFQ ones, or the one embedded in the dn_pipe for fixed-rate flows), * which in turn dispatches them to the appropriate dn_flow_queue * (created dynamically according to the masks). * * The transmit clock for fixed rate flows (ready_event()) selects the * dn_flow_queue to be used to transmit the next packet. For WF2Q, * wfq_ready_event() extract a pipe which in turn selects the right * flow using a number of heaps defined into the pipe itself. */ /* * per flow queue. This contains the flow identifier, the queue * of packets, counters, and parameters used to support both RED and * WF2Q+. * * A dn_flow_queue is created and initialized whenever a packet for * a new flow arrives. */ struct dn_flow_queue { struct dn_flow_queue *next; struct ipfw_flow_id id; struct dn_pkt *head, *tail; /* queue of packets */ u_int len; u_int len_bytes; u_long numbytes; /* credit for transmission (dynamic queues) */ uint64_t tot_pkts; /* statistics counters */ uint64_t tot_bytes; uint32_t drops; int hash_slot; /* debugging/diagnostic */ /* RED parameters */ int avg; /* average queue length est. (scaled) */ int count; /* arrivals since last RED drop */ int random; /* random value (scaled) */ uint32_t q_time; /* start of queue idle time */ /* WF2Q+ support */ struct dn_flow_set *fs; /* parent flow set */ int heap_pos; /* position (index) of struct in heap */ dn_key sched_time; /* current time when queue enters ready_heap */ dn_key S, F; /* start time, finish time */ /* * Setting F < S means the timestamp is invalid. We only need * to test this when the queue is empty. */ }; /* * flow_set descriptor. Contains the "template" parameters for the * queue configuration, and pointers to the hash table of dn_flow_queue's. * * The hash table is an array of lists -- we identify the slot by * hashing the flow-id, then scan the list looking for a match. * The size of the hash table (buckets) is configurable on a per-queue * basis. * * A dn_flow_set is created whenever a new queue or pipe is created (in the * latter case, the structure is located inside the struct dn_pipe). */ struct dn_flow_set { struct dn_flow_set *next; /* next flow set in all_flow_sets list */ u_short fs_nr; /* flow_set number */ u_short flags_fs; #define DN_HAVE_FLOW_MASK 0x0001 #define DN_IS_RED 0x0002 #define DN_IS_GENTLE_RED 0x0004 #define DN_QSIZE_IS_BYTES 0x0008 /* queue size is measured in bytes */ #define DN_NOERROR 0x0010 /* do not report ENOBUFS on drops */ #define DN_IS_PIPE 0x4000 #define DN_IS_QUEUE 0x8000 struct dn_pipe *pipe; /* pointer to parent pipe */ u_short parent_nr; /* parent pipe#, 0 if local to a pipe */ int weight; /* WFQ queue weight */ int qsize; /* queue size in slots or bytes */ int plr; /* pkt loss rate (2^31-1 means 100%) */ struct ipfw_flow_id flow_mask; /* hash table of queues onto this flow_set */ int rq_size; /* number of slots */ int rq_elements; /* active elements */ struct dn_flow_queue **rq; /* array of rq_size entries */ uint32_t last_expired; /* do not expire too frequently */ int backlogged; /* #active queues for this flowset */ /* RED parameters */ #define SCALE_RED 16 #define SCALE(x) ((x) << SCALE_RED) #define SCALE_VAL(x) ((x) >> SCALE_RED) #define SCALE_MUL(x, y) (((x) * (y)) >> SCALE_RED) int w_q; /* queue weight (scaled) */ int max_th; /* maximum threshold for queue (scaled) */ int min_th; /* minimum threshold for queue (scaled) */ int max_p; /* maximum value for p_b (scaled) */ u_int c_1; /* max_p/(max_th-min_th) (scaled) */ u_int c_2; /* max_p*min_th/(max_th-min_th) (scaled) */ u_int c_3; /* for GRED, (1-max_p)/max_th (scaled) */ u_int c_4; /* for GRED, 1 - 2*max_p (scaled) */ u_int *w_q_lookup; /* lookup table for computing (1-w_q)^t */ u_int lookup_depth; /* depth of lookup table */ int lookup_step; /* granularity inside the lookup table */ int lookup_weight; /* equal to (1-w_q)^t / (1-w_q)^(t+1) */ int avg_pkt_size; /* medium packet size */ int max_pkt_size; /* max packet size */ }; /* * Pipe descriptor. Contains global parameters, delay-line queue, * and the flow_set used for fixed-rate queues. * * For WF2Q+ support it also has 3 heaps holding dn_flow_queue: * not_eligible_heap, for queues whose start time is higher * than the virtual time. Sorted by start time. * scheduler_heap, for queues eligible for scheduling. Sorted by * finish time. * idle_heap, all flows that are idle and can be removed. We * do that on each tick so we do not slow down too much * operations during forwarding. * */ struct dn_pipe { /* a pipe */ struct dn_pipe *next; int pipe_nr; /* number */ int bandwidth; /* really, bytes/tick. */ int delay; /* really, ticks */ struct dn_pkt *head, *tail; /* packets in delay line */ /* WF2Q+ */ struct dn_heap scheduler_heap; /* top extract - key Finish time*/ struct dn_heap not_eligible_heap; /* top extract- key Start time */ struct dn_heap idle_heap; /* random extract - key Start=Finish time */ dn_key V; /* virtual time */ int sum; /* sum of weights of all active sessions */ int numbytes; /* bits I can transmit (more or less). */ dn_key sched_time; /* time pipe was scheduled in ready_heap */ /* * When the tx clock come from an interface (if_name[0] != '\0'), its name * is stored below, whereas the ifp is filled when the rule is configured. */ char if_name[IFNAMSIZ]; struct ifnet *ifp; int ready; /* set if ifp != NULL and we got a signal from it */ struct dn_flow_set fs; /* used with fixed-rate flows */ }; #ifdef _KERNEL typedef int ip_dn_ctl_t(struct sockopt *); /* raw_ip.c */ typedef void ip_dn_ruledel_t(void *); /* ip_fw2.c */ typedef int ip_dn_io_t(struct mbuf *m, int pipe_nr, int dir, struct ip_fw_args *fwa); extern ip_dn_ctl_t *ip_dn_ctl_ptr; extern ip_dn_ruledel_t *ip_dn_ruledel_ptr; extern ip_dn_io_t *ip_dn_io_ptr; #define DUMMYNET_LOADED (ip_dn_io_ptr != NULL) #endif #endif /* !_IP_DUMMYNET_H */