+\f
+const char *
+nxm_parse_field_bits(const char *s, uint32_t *headerp, int *ofsp, int *n_bitsp)
+{
+ const char *full_s = s;
+ const char *name;
+ uint32_t header;
+ int start, end;
+ int name_len;
+ int width;
+
+ name = s;
+ name_len = strcspn(s, "[");
+ if (s[name_len] != '[') {
+ ovs_fatal(0, "%s: missing [ looking for field name", full_s);
+ }
+
+ header = parse_nxm_field_name(name, name_len);
+ if (!header) {
+ ovs_fatal(0, "%s: unknown field `%.*s'", full_s, name_len, s);
+ }
+ width = nxm_field_bits(header);
+
+ s += name_len;
+ if (sscanf(s, "[%d..%d]", &start, &end) == 2) {
+ /* Nothing to do. */
+ } else if (sscanf(s, "[%d]", &start) == 1) {
+ end = start;
+ } else if (!strncmp(s, "[]", 2)) {
+ start = 0;
+ end = width - 1;
+ } else {
+ ovs_fatal(0, "%s: syntax error expecting [] or [<bit>] or "
+ "[<start>..<end>]", full_s);
+ }
+ s = strchr(s, ']') + 1;
+
+ if (start > end) {
+ ovs_fatal(0, "%s: starting bit %d is after ending bit %d",
+ full_s, start, end);
+ } else if (start >= width) {
+ ovs_fatal(0, "%s: starting bit %d is not valid because field is only "
+ "%d bits wide", full_s, start, width);
+ } else if (end >= width){
+ ovs_fatal(0, "%s: ending bit %d is not valid because field is only "
+ "%d bits wide", full_s, end, width);
+ }
+
+ *headerp = header;
+ *ofsp = start;
+ *n_bitsp = end - start + 1;
+
+ return s;
+}
+
+void
+nxm_parse_reg_move(struct nx_action_reg_move *move, const char *s)
+{
+ const char *full_s = s;
+ uint32_t src, dst;
+ int src_ofs, dst_ofs;
+ int src_n_bits, dst_n_bits;
+
+ s = nxm_parse_field_bits(s, &src, &src_ofs, &src_n_bits);
+ if (strncmp(s, "->", 2)) {
+ ovs_fatal(0, "%s: missing `->' following source", full_s);
+ }
+ s += 2;
+ s = nxm_parse_field_bits(s, &dst, &dst_ofs, &dst_n_bits);
+ if (*s != '\0') {
+ ovs_fatal(0, "%s: trailing garbage following destination", full_s);
+ }
+
+ if (src_n_bits != dst_n_bits) {
+ ovs_fatal(0, "%s: source field is %d bits wide but destination is "
+ "%d bits wide", full_s, src_n_bits, dst_n_bits);
+ }
+
+ ofputil_init_NXAST_REG_MOVE(move);
+ move->n_bits = htons(src_n_bits);
+ move->src_ofs = htons(src_ofs);
+ move->dst_ofs = htons(dst_ofs);
+ move->src = htonl(src);
+ move->dst = htonl(dst);
+}
+
+void
+nxm_parse_reg_load(struct nx_action_reg_load *load, const char *s)
+{
+ const char *full_s = s;
+ uint32_t dst;
+ int ofs, n_bits;
+ uint64_t value;
+
+ value = strtoull(s, (char **) &s, 0);
+ if (strncmp(s, "->", 2)) {
+ ovs_fatal(0, "%s: missing `->' following value", full_s);
+ }
+ s += 2;
+ s = nxm_parse_field_bits(s, &dst, &ofs, &n_bits);
+ if (*s != '\0') {
+ ovs_fatal(0, "%s: trailing garbage following destination", full_s);
+ }
+
+ if (n_bits < 64 && (value >> n_bits) != 0) {
+ ovs_fatal(0, "%s: value %"PRIu64" does not fit into %d bits",
+ full_s, value, n_bits);
+ }
+
+ ofputil_init_NXAST_REG_LOAD(load);
+ load->ofs_nbits = nxm_encode_ofs_nbits(ofs, n_bits);
+ load->dst = htonl(dst);
+ load->value = htonll(value);
+}
+\f
+/* nxm_format_reg_move(), nxm_format_reg_load(). */
+
+void
+nxm_format_field_bits(struct ds *s, uint32_t header, int ofs, int n_bits)
+{
+ format_nxm_field_name(s, header);
+ if (ofs == 0 && n_bits == nxm_field_bits(header)) {
+ ds_put_cstr(s, "[]");
+ } else if (n_bits == 1) {
+ ds_put_format(s, "[%d]", ofs);
+ } else {
+ ds_put_format(s, "[%d..%d]", ofs, ofs + n_bits - 1);
+ }
+}
+
+void
+nxm_format_reg_move(const struct nx_action_reg_move *move, struct ds *s)
+{
+ int n_bits = ntohs(move->n_bits);
+ int src_ofs = ntohs(move->src_ofs);
+ int dst_ofs = ntohs(move->dst_ofs);
+ uint32_t src = ntohl(move->src);
+ uint32_t dst = ntohl(move->dst);
+
+ ds_put_format(s, "move:");
+ nxm_format_field_bits(s, src, src_ofs, n_bits);
+ ds_put_cstr(s, "->");
+ nxm_format_field_bits(s, dst, dst_ofs, n_bits);
+}
+
+void
+nxm_format_reg_load(const struct nx_action_reg_load *load, struct ds *s)
+{
+ int ofs = nxm_decode_ofs(load->ofs_nbits);
+ int n_bits = nxm_decode_n_bits(load->ofs_nbits);
+ uint32_t dst = ntohl(load->dst);
+ uint64_t value = ntohll(load->value);
+
+ ds_put_format(s, "load:%#"PRIx64"->", value);
+ nxm_format_field_bits(s, dst, ofs, n_bits);
+}
+\f
+/* nxm_check_reg_move(), nxm_check_reg_load(). */
+
+static bool
+field_ok(const struct mf_field *mf, const struct flow *flow, int size)
+{
+ return (mf
+ && mf_are_prereqs_ok(mf, flow)
+ && size <= nxm_field_bits(mf->nxm_header));
+}
+
+int
+nxm_check_reg_move(const struct nx_action_reg_move *action,
+ const struct flow *flow)
+{
+ int src_ofs, dst_ofs, n_bits;
+ int error;
+
+ n_bits = ntohs(action->n_bits);
+ src_ofs = ntohs(action->src_ofs);
+ dst_ofs = ntohs(action->dst_ofs);
+
+ error = nxm_src_check(action->src, src_ofs, n_bits, flow);
+ if (error) {
+ return error;
+ }
+
+ return nxm_dst_check(action->dst, dst_ofs, n_bits, flow);
+}
+
+/* Given a flow, checks that the source field represented by 'src_header'
+ * in the range ['ofs', 'ofs' + 'n_bits') is valid. */
+int
+nxm_src_check(ovs_be32 src_header_, unsigned int ofs, unsigned int n_bits,
+ const struct flow *flow)
+{
+ uint32_t src_header = ntohl(src_header_);
+ const struct mf_field *src = mf_from_nxm_header(src_header);
+
+ if (!n_bits) {
+ VLOG_WARN_RL(&rl, "zero bit source field");
+ } else if (NXM_HASMASK(src_header) || !field_ok(src, flow, ofs + n_bits)) {
+ VLOG_WARN_RL(&rl, "invalid source field");
+ } else {
+ return 0;
+ }
+
+ return BAD_ARGUMENT;
+}
+
+/* Given a flow, checks that the destination field represented by 'dst_header'
+ * in the range ['ofs', 'ofs' + 'n_bits') is valid. */
+int
+nxm_dst_check(ovs_be32 dst_header_, unsigned int ofs, unsigned int n_bits,
+ const struct flow *flow)
+{
+ uint32_t dst_header = ntohl(dst_header_);
+ const struct mf_field *dst = mf_from_nxm_header(dst_header);
+
+ if (!n_bits) {
+ VLOG_WARN_RL(&rl, "zero bit destination field");
+ } else if (NXM_HASMASK(dst_header) || !field_ok(dst, flow, ofs + n_bits)) {
+ VLOG_WARN_RL(&rl, "invalid destination field");
+ } else if (!dst->writable) {
+ VLOG_WARN_RL(&rl, "destination field is not writable");
+ } else {
+ return 0;
+ }
+
+ return BAD_ARGUMENT;
+}
+
+int
+nxm_check_reg_load(const struct nx_action_reg_load *action,
+ const struct flow *flow)
+{
+ unsigned int ofs = nxm_decode_ofs(action->ofs_nbits);
+ unsigned int n_bits = nxm_decode_n_bits(action->ofs_nbits);
+ int error;
+
+ error = nxm_dst_check(action->dst, ofs, n_bits, flow);
+ if (error) {
+ return error;
+ }
+
+ /* Reject 'action' if a bit numbered 'n_bits' or higher is set to 1 in
+ * action->value. */
+ if (n_bits < 64 && ntohll(action->value) >> n_bits) {
+ return BAD_ARGUMENT;
+ }
+
+ return 0;
+}
+\f
+/* nxm_execute_reg_move(), nxm_execute_reg_load(). */
+
+static void
+bitwise_copy(const void *src_, unsigned int src_len, unsigned int src_ofs,
+ void *dst_, unsigned int dst_len, unsigned int dst_ofs,
+ unsigned int n_bits)
+{
+ const uint8_t *src = src_;
+ uint8_t *dst = dst_;
+
+ src += src_len - (src_ofs / 8 + 1);
+ src_ofs %= 8;
+
+ dst += dst_len - (dst_ofs / 8 + 1);
+ dst_ofs %= 8;
+
+ if (src_ofs == 0 && dst_ofs == 0) {
+ unsigned int n_bytes = n_bits / 8;
+ if (n_bytes) {
+ dst -= n_bytes - 1;
+ src -= n_bytes - 1;
+ memcpy(dst, src, n_bytes);
+
+ n_bits %= 8;
+ src--;
+ dst--;
+ }
+ if (n_bits) {
+ uint8_t mask = (1 << n_bits) - 1;
+ *dst = (*dst & ~mask) | (*src & mask);
+ }
+ } else {
+ while (n_bits > 0) {
+ unsigned int max_copy = 8 - MAX(src_ofs, dst_ofs);
+ unsigned int chunk = MIN(n_bits, max_copy);
+ uint8_t mask = ((1 << chunk) - 1) << dst_ofs;
+
+ *dst &= ~mask;
+ *dst |= ((*src >> src_ofs) << dst_ofs) & mask;
+
+ src_ofs += chunk;
+ if (src_ofs == 8) {
+ src--;
+ src_ofs = 0;
+ }
+ dst_ofs += chunk;
+ if (dst_ofs == 8) {
+ dst--;
+ dst_ofs = 0;
+ }
+ n_bits -= chunk;
+ }
+ }
+}
+
+/* Returns the value of the NXM field corresponding to 'header' at 'ofs_nbits'
+ * in 'flow'. */
+uint64_t
+nxm_read_field_bits(ovs_be32 header, ovs_be16 ofs_nbits,
+ const struct flow *flow)
+{
+ const struct mf_field *field = mf_from_nxm_header(ntohl(header));
+ union mf_value value;
+ union mf_value bits;
+
+ mf_get_value(field, flow, &value);
+ bits.be64 = htonll(0);
+ bitwise_copy(&value, field->n_bytes, nxm_decode_ofs(ofs_nbits),
+ &bits, sizeof bits.be64, 0,
+ nxm_decode_n_bits(ofs_nbits));
+ return ntohll(bits.be64);
+}
+
+void
+nxm_execute_reg_move(const struct nx_action_reg_move *action,
+ struct flow *flow)
+{
+ const struct mf_field *src = mf_from_nxm_header(ntohl(action->src));
+ const struct mf_field *dst = mf_from_nxm_header(ntohl(action->dst));
+ union mf_value src_value;
+ union mf_value dst_value;
+
+ mf_get_value(dst, flow, &dst_value);
+ mf_get_value(src, flow, &src_value);
+ bitwise_copy(&src_value, src->n_bytes, ntohs(action->src_ofs),
+ &dst_value, dst->n_bytes, ntohs(action->dst_ofs),
+ ntohs(action->n_bits));
+ mf_set_flow_value(dst, &dst_value, flow);
+}
+
+void
+nxm_execute_reg_load(const struct nx_action_reg_load *action,
+ struct flow *flow)
+{
+ nxm_reg_load(action->dst, action->ofs_nbits, ntohll(action->value), flow);
+}
+
+/* Calculates ofs and n_bits from the given 'ofs_nbits' parameter, and copies
+ * 'src_data'[0:n_bits] to 'dst_header'[ofs:ofs+n_bits] in the given 'flow'. */
+void
+nxm_reg_load(ovs_be32 dst_header, ovs_be16 ofs_nbits, uint64_t src_data,
+ struct flow *flow)
+{
+ const struct mf_field *dst = mf_from_nxm_header(ntohl(dst_header));
+ int n_bits = nxm_decode_n_bits(ofs_nbits);
+ int dst_ofs = nxm_decode_ofs(ofs_nbits);
+ union mf_value dst_value;
+ union mf_value src_value;
+
+ mf_get_value(dst, flow, &dst_value);
+ src_value.be64 = htonll(src_data);
+ bitwise_copy(&src_value, sizeof src_value.be64, 0,
+ &dst_value, dst->n_bytes, dst_ofs,
+ n_bits);
+ mf_set_flow_value(dst, &dst_value, flow);
+}