autopath: Create the autopath action.

The newly created autopath action will be the way OpenFlow
interacts with the existing bonding infrastructure.

6 files changed, 171 insertions, 0 deletions

diff --git a/lib/automake.mk b/lib/automake.mk
index ffebefa5..802cc992 100644
--- a/lib/automake.mk
+++ b/lib/automake.mk
@@ -10,6 +10,8 @@ noinst_LIBRARIES += lib/libopenvswitch.a
 lib_libopenvswitch_a_SOURCES = \
 	lib/aes128.c \
 	lib/aes128.h \
+	lib/autopath.c \
+	lib/autopath.h \
 	lib/backtrace.c \
 	lib/backtrace.h \
 	lib/bitmap.c \
diff --git a/lib/autopath.c b/lib/autopath.c
new file mode 100644
index 00000000..889b037b
--- /dev/null
+++ b/lib/autopath.c
@@ -0,0 +1,110 @@
+/*
+ * Copyright (c) 2011 Nicira Networks.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <config.h>
+
+#include "autopath.h"
+
+#include <inttypes.h>
+#include <stdlib.h>
+
+#include "flow.h"
+#include "nx-match.h"
+#include "ofp-util.h"
+#include "openflow/nicira-ext.h"
+#include "vlog.h"
+
+VLOG_DEFINE_THIS_MODULE(autopath);
+
+static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(1, 5);
+
+/* Loads 'ofp_port' into the appropriate register in accordance with the
+ * autopath action. */
+void
+autopath_execute(const struct nx_action_autopath *ap, struct flow *flow,
+                 uint16_t ofp_port)
+{
+    uint32_t *reg = &flow->regs[NXM_NX_REG_IDX(ntohl(ap->dst))];
+    int ofs = nxm_decode_ofs(ap->ofs_nbits);
+    int n_bits = nxm_decode_n_bits(ap->ofs_nbits);
+    uint32_t mask = n_bits == 32 ? UINT32_MAX : (UINT32_C(1) << n_bits) - 1;
+    *reg = (*reg & ~(mask << ofs)) | ((ofp_port & mask) << ofs);
+}
+
+void
+autopath_parse(struct nx_action_autopath *ap, const char *s_)
+{
+    char *s;
+    uint32_t reg;
+    int id_int, ofs, n_bits;
+    char *id_str, *dst, *save_ptr;
+
+    s = xstrdup(s_);
+    save_ptr = NULL;
+    id_str = strtok_r(s, ", ", &save_ptr);
+    dst = strtok_r(NULL, ", ", &save_ptr);
+
+    if (!dst) {
+        ovs_fatal(0, "%s: not enough arguments to autopath action", s_);
+    }
+
+    id_int = atoi(id_str);
+    if (id_int < 1 || id_int > UINT32_MAX) {
+        ovs_fatal(0, "%s: autopath id %d is not in valid range "
+                  "1 to %"PRIu32, s_, id_int, UINT32_MAX);
+    }
+
+    nxm_parse_field_bits(dst, &reg, &ofs, &n_bits);
+    if (!NXM_IS_NX_REG(reg) || NXM_NX_REG_IDX(reg) >= FLOW_N_REGS) {
+        ovs_fatal(0, "%s: destination field must be a register", s_);
+    }
+
+    if (n_bits < 16) {
+        ovs_fatal(0, "%s: %d-bit destination field has %u possible values, "
+                  "less than required 65536", s_, n_bits, 1u << n_bits);
+    }
+
+    memset(ap, 0, sizeof *ap);
+    ap->type = htons(OFPAT_VENDOR);
+    ap->len = htons(sizeof *ap);
+    ap->vendor = htonl(NX_VENDOR_ID);
+    ap->subtype = htons(NXAST_AUTOPATH);
+    ap->id = htonl(id_int);
+    ap->ofs_nbits = nxm_encode_ofs_nbits(ofs, n_bits);
+    ap->dst = htonl(reg);
+
+    free(s);
+}
+
+int
+autopath_check(const struct nx_action_autopath *ap)
+{
+    uint32_t dst = ntohl(ap->dst);
+    int ofs = nxm_decode_ofs(ap->ofs_nbits);
+    int n_bits = nxm_decode_n_bits(ap->ofs_nbits);
+
+    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) {
+        VLOG_WARN_RL(&rl, "minimum of 16 bits required in output field");
+    } else {
+        return 0;
+    }
+
+    return ofp_mkerr(OFPET_BAD_ACTION, OFPBAC_BAD_ARGUMENT);
+}
diff --git a/lib/autopath.h b/lib/autopath.h
new file mode 100644
index 00000000..ba55f90d
--- /dev/null
+++ b/lib/autopath.h
@@ -0,0 +1,34 @@
+/*
+ * Copyright (c) 2011 Nicira Networks.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef AUTOPATH_H
+#define AUTOPATH_H 1
+
+#include <stdint.h>
+
+struct flow;
+struct nx_action_autopath;
+
+/* NXAST_AUTOPATH  helper functions.
+ *
+ * See include/openflow/nicira-ext.h for NXAST_AUTOPATH specification. */
+
+void autopath_execute(const struct nx_action_autopath *, struct flow *,
+                      uint16_t ofp_port);
+void autopath_parse(struct nx_action_autopath *, const char *);
+int autopath_check(const struct nx_action_autopath *);
+
+#endif /* autopath.h */
diff --git a/lib/ofp-parse.c b/lib/ofp-parse.c
index de7cd9c7..4c4811b6 100644
--- a/lib/ofp-parse.c
+++ b/lib/ofp-parse.c
@@ -22,6 +22,7 @@
 #include <errno.h>
 #include <stdlib.h>
 
+#include "autopath.h"
 #include "byte-order.h"
 #include "dynamic-string.h"
 #include "netdev.h"
@@ -453,6 +454,10 @@ str_to_action(char *str, struct ofpbuf *b)
             struct nx_action_multipath *nam;
             nam = ofpbuf_put_uninit(b, sizeof *nam);
             multipath_parse(nam, arg);
+        } else if (!strcasecmp(act, "autopath")) {
+            struct nx_action_autopath *naa;
+            naa = ofpbuf_put_uninit(b, sizeof *naa);
+            autopath_parse(naa, arg);
         } else if (!strcasecmp(act, "output")) {
             put_output_action(b, str_to_u32(arg));
         } else if (!strcasecmp(act, "enqueue")) {
diff --git a/lib/ofp-print.c b/lib/ofp-print.c
index 1cd94626..f5eb9ad0 100644
--- a/lib/ofp-print.c
+++ b/lib/ofp-print.c
@@ -219,6 +219,7 @@ nx_action_len(enum nx_action_subtype subtype)
     case NXAST_NOTE: return -1;
     case NXAST_SET_TUNNEL64: return sizeof(struct nx_action_set_tunnel64);
     case NXAST_MULTIPATH: return sizeof(struct nx_action_multipath);
+    case NXAST_AUTOPATH: return sizeof (struct nx_action_autopath);
     default: return -1;
     }
 }
@@ -244,6 +245,7 @@ ofp_print_nx_action(struct ds *string, const struct nx_action_header *nah)
         const struct nx_action_reg_move *move;
         const struct nx_action_reg_load *load;
         const struct nx_action_multipath *nam;
+        const struct nx_action_autopath *naa;
 
         switch ((enum nx_action_subtype) subtype) {
         case NXAST_RESUBMIT:
@@ -295,6 +297,15 @@ ofp_print_nx_action(struct ds *string, const struct nx_action_header *nah)
             multipath_format(nam, string);
             return;
 
+        case NXAST_AUTOPATH:
+            naa = (const struct nx_action_autopath *)nah;
+            ds_put_format(string, "autopath(%u,", ntohl(naa->id));
+            nxm_format_field_bits(string, ntohl(naa->dst),
+                                  nxm_decode_ofs(naa->ofs_nbits),
+                                  nxm_decode_n_bits(naa->ofs_nbits));
+            ds_put_char(string, ')');
+            return;
+
         case NXAST_SNAT__OBSOLETE:
         default:
             break;
diff --git a/lib/ofp-util.c b/lib/ofp-util.c
index cc448bcd..c49b0798 100644
--- a/lib/ofp-util.c
+++ b/lib/ofp-util.c
@@ -19,6 +19,7 @@
 #include <errno.h>
 #include <inttypes.h>
 #include <stdlib.h>
+#include "autopath.h"
 #include "byte-order.h"
 #include "classifier.h"
 #include "dynamic-string.h"
@@ -2014,6 +2015,14 @@ check_nicira_action(const union ofp_action *a, unsigned int len,
         }
         return multipath_check((const struct nx_action_multipath *) a);
 
+    case NXAST_AUTOPATH:
+        error = check_nx_action_exact_len(
+            nah, len, sizeof(struct nx_action_autopath));
+        if (error) {
+            return error;
+        }
+        return autopath_check((const struct nx_action_autopath *) a);
+
     case NXAST_SNAT__OBSOLETE:
     default:
         VLOG_WARN_RL(&bad_ofmsg_rl,