X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=lib%2Fmultipath.c;h=a6f549ca6715ff138710d4f92f6fb748eaeb0062;hb=HEAD;hp=19e7b3610083f82f0e61bfdd638abc1c4256d4a0;hpb=ff55ea1f29360533699edb77747a919505282057;p=sliver-openvswitch.git

diff --git a/lib/multipath.c b/lib/multipath.c
index 19e7b3610..a6f549ca6 100644
--- a/lib/multipath.c
+++ b/lib/multipath.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2010, 2011 Nicira Networks.
+ * Copyright (c) 2010, 2011, 2012, 2013 Nicira, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -23,6 +23,8 @@
 #include <netinet/in.h>
 #include "dynamic-string.h"
 #include "nx-match.h"
+#include "ofp-actions.h"
+#include "ofp-errors.h"
 #include "ofp-util.h"
 #include "openflow/nicira-ext.h"
 #include "packets.h"
@@ -32,73 +34,87 @@ VLOG_DEFINE_THIS_MODULE(multipath);
 
 static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(1, 5);
 
-/* multipath_check(). */
-int
-multipath_check(const struct nx_action_multipath *mp)
+/* Converts 'nam' into 'mp'.  Returns 0 if successful, otherwise an
+ * OFPERR_*. */
+enum ofperr
+multipath_from_openflow(const struct nx_action_multipath *nam,
+                        struct ofpact_multipath *mp)
 {
-    uint32_t dst = ntohl(mp->dst);
-    int ofs = nxm_decode_ofs(mp->ofs_nbits);
-    int n_bits = nxm_decode_n_bits(mp->ofs_nbits);
-
-    if (mp->fields != htons(NX_MP_FIELDS_ETH_SRC)
-        && mp->fields != htons(NX_MP_FIELDS_SYMMETRIC_L4)) {
-        VLOG_WARN_RL(&rl, "unsupported fields %"PRIu16, ntohs(mp->fields));
-    } else if (mp->algorithm != htons(NX_MP_ALG_MODULO_N)
-               && mp->algorithm != htons(NX_MP_ALG_HASH_THRESHOLD)
-               && mp->algorithm != htons(NX_MP_ALG_HRW)
-               && mp->algorithm != htons(NX_MP_ALG_ITER_HASH)) {
-        VLOG_WARN_RL(&rl, "unsupported algorithm %"PRIu16,
-                     ntohs(mp->algorithm));
-    } else if (!NXM_IS_NX_REG(dst) || NXM_NX_REG_IDX(dst) >= FLOW_N_REGS) {
-        VLOG_WARN_RL(&rl, "unsupported destination field %#"PRIx32, dst);
-    } else if (ofs + n_bits > nxm_field_bits(dst)) {
-        VLOG_WARN_RL(&rl, "destination overflows output field");
-    } else if (n_bits < 16 && ntohs(mp->max_link) > (1u << n_bits)) {
-        VLOG_WARN_RL(&rl, "max_link overflows output field");
-    } else {
-        return 0;
+    uint32_t n_links = ntohs(nam->max_link) + 1;
+    size_t min_n_bits = log_2_ceil(n_links);
+
+    ofpact_init_MULTIPATH(mp);
+    mp->fields = ntohs(nam->fields);
+    mp->basis = ntohs(nam->basis);
+    mp->algorithm = ntohs(nam->algorithm);
+    mp->max_link = ntohs(nam->max_link);
+    mp->arg = ntohl(nam->arg);
+    mp->dst.field = mf_from_nxm_header(ntohl(nam->dst));
+    mp->dst.ofs = nxm_decode_ofs(nam->ofs_nbits);
+    mp->dst.n_bits = nxm_decode_n_bits(nam->ofs_nbits);
+
+    if (!flow_hash_fields_valid(mp->fields)) {
+        VLOG_WARN_RL(&rl, "unsupported fields %d", (int) mp->fields);
+        return OFPERR_OFPBAC_BAD_ARGUMENT;
+    } else if (mp->algorithm != NX_MP_ALG_MODULO_N
+               && mp->algorithm != NX_MP_ALG_HASH_THRESHOLD
+               && mp->algorithm != NX_MP_ALG_HRW
+               && mp->algorithm != NX_MP_ALG_ITER_HASH) {
+        VLOG_WARN_RL(&rl, "unsupported algorithm %d", (int) mp->algorithm);
+        return OFPERR_OFPBAC_BAD_ARGUMENT;
+    } else if (mp->dst.n_bits < min_n_bits) {
+        VLOG_WARN_RL(&rl, "multipath action requires at least %"PRIuSIZE" bits for "
+                     "%"PRIu32" links", min_n_bits, n_links);
+        return OFPERR_OFPBAC_BAD_ARGUMENT;
     }
 
-    return ofp_mkerr(OFPET_BAD_ACTION, OFPBAC_BAD_ARGUMENT);
+    return multipath_check(mp, NULL);
+}
+
+/* Checks that 'mp' is valid on flow.  Returns 0 if it is valid, otherwise an
+ * OFPERR_*. */
+enum ofperr
+multipath_check(const struct ofpact_multipath *mp,
+                const struct flow *flow)
+{
+    return mf_check_dst(&mp->dst, flow);
+}
+
+/* Converts 'mp' into an OpenFlow NXAST_MULTIPATH action, which it appends to
+ * 'openflow'. */
+void
+multipath_to_nxast(const struct ofpact_multipath *mp, struct ofpbuf *openflow)
+{
+    struct nx_action_multipath *nam = ofputil_put_NXAST_MULTIPATH(openflow);
+
+    nam->fields = htons(mp->fields);
+    nam->basis = htons(mp->basis);
+    nam->algorithm = htons(mp->algorithm);
+    nam->max_link = htons(mp->max_link);
+    nam->arg = htonl(mp->arg);
+    nam->ofs_nbits = nxm_encode_ofs_nbits(mp->dst.ofs, mp->dst.n_bits);
+    nam->dst = htonl(mp->dst.field->nxm_header);
 }
 
 /* multipath_execute(). */
 
-static uint32_t multipath_hash(const struct flow *, enum nx_mp_fields,
-                               uint16_t basis);
 static uint16_t multipath_algorithm(uint32_t hash, enum nx_mp_algorithm,
                                     unsigned int n_links, unsigned int arg);
 
+/* Executes 'mp' based on the current contents of 'flow', writing the results
+ * back into 'flow'.  Sets fields in 'wc' that were used to calculate
+ * the result. */
 void
-multipath_execute(const struct nx_action_multipath *mp, struct flow *flow)
+multipath_execute(const struct ofpact_multipath *mp, struct flow *flow,
+                  struct flow_wildcards *wc)
 {
     /* Calculate value to store. */
-    uint32_t hash = multipath_hash(flow, ntohs(mp->fields), ntohs(mp->basis));
-    uint16_t link = multipath_algorithm(hash, ntohs(mp->algorithm),
-                                        ntohs(mp->max_link) + 1,
-                                        ntohl(mp->arg));
-
-    /* Store it. */
-    uint32_t *reg = &flow->regs[NXM_NX_REG_IDX(ntohl(mp->dst))];
-    int ofs = nxm_decode_ofs(mp->ofs_nbits);
-    int n_bits = nxm_decode_n_bits(mp->ofs_nbits);
-    uint32_t mask = n_bits == 32 ? UINT32_MAX : (UINT32_C(1) << n_bits) - 1;
-    *reg = (*reg & ~(mask << ofs)) | (link << ofs);
-}
-
-static uint32_t
-multipath_hash(const struct flow *flow, enum nx_mp_fields fields,
-               uint16_t basis)
-{
-    switch (fields) {
-    case NX_MP_FIELDS_ETH_SRC:
-        return hash_bytes(flow->dl_src, sizeof flow->dl_src, basis);
+    uint32_t hash = flow_hash_fields(flow, mp->fields, mp->basis);
+    uint16_t link = multipath_algorithm(hash, mp->algorithm,
+                                        mp->max_link + 1, mp->arg);
 
-    case NX_MP_FIELDS_SYMMETRIC_L4:
-        return flow_hash_symmetric_l4(flow, basis);
-    }
-
-    NOT_REACHED();
+    flow_mask_hash_fields(flow, wc, mp->fields);
+    nxm_reg_load(&mp->dst, link, flow, wc);
 }
 
 static uint16_t
@@ -173,84 +189,97 @@ multipath_algorithm(uint32_t hash, enum nx_mp_algorithm algorithm,
         return algorithm_iter_hash(hash, n_links, arg);
     }
 
-    NOT_REACHED();
+    OVS_NOT_REACHED();
 }
 
-/* multipath_parse(). */
-
-void
-multipath_parse(struct nx_action_multipath *mp, const char *s_)
+/* Parses 's_' as a set of arguments to the "multipath" action and initializes
+ * 'mp' accordingly.  ovs-ofctl(8) describes the format parsed.
+ *
+ * Returns NULL if successful, otherwise a malloc()'d string describing the
+ * error.  The caller is responsible for freeing the returned string.*/
+static char * WARN_UNUSED_RESULT
+multipath_parse__(struct ofpact_multipath *mp, const char *s_, char *s)
 {
-    char *s = xstrdup(s_);
     char *save_ptr = NULL;
-    char *fields, *basis, *algorithm, *n_links, *arg, *dst;
-    uint32_t header;
-    int ofs, n_bits;
+    char *fields, *basis, *algorithm, *n_links_str, *arg, *dst;
+    char *error;
+    int n_links;
 
     fields = strtok_r(s, ", ", &save_ptr);
     basis = strtok_r(NULL, ", ", &save_ptr);
     algorithm = strtok_r(NULL, ", ", &save_ptr);
-    n_links = strtok_r(NULL, ", ", &save_ptr);
+    n_links_str = strtok_r(NULL, ", ", &save_ptr);
     arg = strtok_r(NULL, ", ", &save_ptr);
     dst = strtok_r(NULL, ", ", &save_ptr);
     if (!dst) {
-        ovs_fatal(0, "%s: not enough arguments to multipath action", s);
+        return xasprintf("%s: not enough arguments to multipath action", s_);
     }
 
-    memset(mp, 0, sizeof *mp);
-    mp->type = htons(OFPAT_VENDOR);
-    mp->len = htons(sizeof *mp);
-    mp->vendor = htonl(NX_VENDOR_ID);
-    mp->subtype = htons(NXAST_MULTIPATH);
+    ofpact_init_MULTIPATH(mp);
     if (!strcasecmp(fields, "eth_src")) {
-        mp->fields = htons(NX_MP_FIELDS_ETH_SRC);
+        mp->fields = NX_HASH_FIELDS_ETH_SRC;
     } else if (!strcasecmp(fields, "symmetric_l4")) {
-        mp->fields = htons(NX_MP_FIELDS_SYMMETRIC_L4);
+        mp->fields = NX_HASH_FIELDS_SYMMETRIC_L4;
     } else {
-        ovs_fatal(0, "%s: unknown fields `%s'", s, fields);
+        return xasprintf("%s: unknown fields `%s'", s_, fields);
     }
-    mp->basis = htons(atoi(basis));
+    mp->basis = atoi(basis);
     if (!strcasecmp(algorithm, "modulo_n")) {
-        mp->algorithm = htons(NX_MP_ALG_MODULO_N);
+        mp->algorithm = NX_MP_ALG_MODULO_N;
     } else if (!strcasecmp(algorithm, "hash_threshold")) {
-        mp->algorithm = htons(NX_MP_ALG_HASH_THRESHOLD);
+        mp->algorithm = NX_MP_ALG_HASH_THRESHOLD;
     } else if (!strcasecmp(algorithm, "hrw")) {
-        mp->algorithm = htons(NX_MP_ALG_HRW);
+        mp->algorithm = NX_MP_ALG_HRW;
     } else if (!strcasecmp(algorithm, "iter_hash")) {
-        mp->algorithm = htons(NX_MP_ALG_ITER_HASH);
+        mp->algorithm = NX_MP_ALG_ITER_HASH;
     } else {
-        ovs_fatal(0, "%s: unknown algorithm `%s'", s, algorithm);
+        return xasprintf("%s: unknown algorithm `%s'", s_, algorithm);
+    }
+    n_links = atoi(n_links_str);
+    if (n_links < 1 || n_links > 65536) {
+        return xasprintf("%s: n_links %d is not in valid range 1 to 65536",
+                         s_, n_links);
+    }
+    mp->max_link = n_links - 1;
+    mp->arg = atoi(arg);
+
+    error = mf_parse_subfield(&mp->dst, dst);
+    if (error) {
+        return error;
+    }
+    if (mp->dst.n_bits < 16 && n_links > (1u << mp->dst.n_bits)) {
+        return xasprintf("%s: %d-bit destination field has %u possible "
+                         "values, less than specified n_links %d",
+                         s_, mp->dst.n_bits, 1u << mp->dst.n_bits, n_links);
     }
-    mp->max_link = htons(atoi(n_links) - 1);
-    mp->arg = htonl(atoi(arg));
 
-    nxm_parse_field_bits(dst, &header, &ofs, &n_bits);
-    mp->ofs_nbits = nxm_encode_ofs_nbits(ofs, n_bits);
-    mp->dst = htonl(header);
+    return NULL;
+}
 
+/* Parses 's_' as a set of arguments to the "multipath" action and initializes
+ * 'mp' accordingly.  ovs-ofctl(8) describes the format parsed.
+ *
+ * Returns NULL if successful, otherwise a malloc()'d string describing the
+ * error.  The caller is responsible for freeing the returned string. */
+char * WARN_UNUSED_RESULT
+multipath_parse(struct ofpact_multipath *mp, const char *s_)
+{
+    char *s = xstrdup(s_);
+    char *error = multipath_parse__(mp, s_, s);
     free(s);
+    return error;
 }
 
+/* Appends a description of 'mp' to 's', in the format that ovs-ofctl(8)
+ * describes. */
 void
-multipath_format(const struct nx_action_multipath *mp, struct ds *s)
+multipath_format(const struct ofpact_multipath *mp, struct ds *s)
 {
     const char *fields, *algorithm;
 
-    uint16_t mp_fields    = ntohs(mp->fields);
-    uint16_t mp_algorithm = ntohs(mp->algorithm);
-
-    switch ((enum nx_mp_fields) mp_fields) {
-    case NX_MP_FIELDS_ETH_SRC:
-        fields = "eth_src";
-        break;
-    case NX_MP_FIELDS_SYMMETRIC_L4:
-        fields = "symmetric_l4";
-        break;
-    default:
-        fields = "<unknown>";
-    }
+    fields = flow_hash_fields_to_str(mp->fields);
 
-    switch ((enum nx_mp_algorithm) mp_algorithm) {
+    switch (mp->algorithm) {
     case NX_MP_ALG_MODULO_N:
         algorithm = "modulo_n";
         break;
@@ -268,9 +297,8 @@ multipath_format(const struct nx_action_multipath *mp, struct ds *s)
     }
 
     ds_put_format(s, "multipath(%s,%"PRIu16",%s,%d,%"PRIu16",",
-                  fields, ntohs(mp->basis), algorithm, ntohs(mp->max_link) + 1,
-                  ntohl(mp->arg));
-    nxm_format_field_bits(s, ntohl(mp->dst), nxm_decode_ofs(mp->ofs_nbits),
-                          nxm_decode_n_bits(mp->ofs_nbits));
+                  fields, mp->basis, algorithm, mp->max_link + 1,
+                  mp->arg);
+    mf_format_subfield(&mp->dst, s);
     ds_put_char(s, ')');
 }