nxm_check_reg_move(const struct nx_action_reg_move *action,
const struct flow *flow)
{
- const struct nxm_field *src;
- const struct nxm_field *dst;
+ int src_ofs, dst_ofs, n_bits;
+ int error;
- if (action->n_bits == htons(0)) {
- return BAD_ARGUMENT;
- }
+ n_bits = ntohs(action->n_bits);
+ src_ofs = ntohs(action->src_ofs);
+ dst_ofs = ntohs(action->dst_ofs);
- src = nxm_field_lookup(ntohl(action->src));
- if (!field_ok(src, flow, ntohs(action->src_ofs) + ntohs(action->n_bits))) {
- return BAD_ARGUMENT;
+ error = nxm_src_check(action->src, src_ofs, n_bits, flow);
+ if (error) {
+ return error;
}
- dst = nxm_field_lookup(ntohl(action->dst));
- if (!field_ok(dst, flow, ntohs(action->dst_ofs) + ntohs(action->n_bits))) {
- return BAD_ARGUMENT;
- }
+ return nxm_dst_check(action->dst, dst_ofs, n_bits, flow);
+}
- if (!dst->writable) {
- return BAD_ARGUMENT;
+/* 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)
+{
+ const struct nxm_field *src = nxm_field_lookup(ntohl(src_header));
+
+ if (!n_bits) {
+ VLOG_WARN_RL(&rl, "zero bit source field");
+ } else if (!field_ok(src, flow, ofs + n_bits)) {
+ VLOG_WARN_RL(&rl, "invalid source field");
+ } else {
+ return 0;
}
- return 0;
+ return BAD_ARGUMENT;
}
/* Given a flow, checks that the destination field represented by 'dst_header'
- * and 'ofs_nbits' is valid and large enough for 'min_n_bits' bits of data. */
+ * in the range ['ofs', 'ofs' + 'n_bits') is valid. */
int
-nxm_dst_check(ovs_be32 dst_header, ovs_be16 ofs_nbits, size_t min_n_bits,
+nxm_dst_check(ovs_be32 dst_header, unsigned int ofs, unsigned int n_bits,
const struct flow *flow)
{
- const struct nxm_field *dst;
- int ofs, n_bits;
-
- ofs = nxm_decode_ofs(ofs_nbits);
- n_bits = nxm_decode_n_bits(ofs_nbits);
- dst = nxm_field_lookup(ntohl(dst_header));
+ const struct nxm_field *dst = nxm_field_lookup(ntohl(dst_header));
- if (!field_ok(dst, flow, ofs + n_bits)) {
+ if (!n_bits) {
+ VLOG_WARN_RL(&rl, "zero bit destination field");
+ } else if (!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 if (n_bits < min_n_bits) {
- VLOG_WARN_RL(&rl, "insufficient bits in destination");
} else {
return 0;
}
nxm_check_reg_load(const struct nx_action_reg_load *action,
const struct flow *flow)
{
- int n_bits;
+ 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, action->ofs_nbits, 0, flow);
+ 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. */
- n_bits = nxm_decode_n_bits(action->ofs_nbits);
if (n_bits < 64 && ntohll(action->value) >> n_bits) {
return BAD_ARGUMENT;
}
NOT_REACHED();
}
+/* 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)
+{
+ int n_bits = nxm_decode_n_bits(ofs_nbits);
+ int ofs = nxm_decode_ofs(ofs_nbits);
+ uint64_t mask, data;
+
+ mask = n_bits == 64 ? UINT64_MAX : (UINT64_C(1) << n_bits) - 1;
+ data = nxm_read_field(nxm_field_lookup(ntohl(header)), flow);
+ data = (data >> ofs) & mask;
+
+ return data;
+}
+
static void
nxm_write_field(const struct nxm_field *dst, struct flow *flow,
uint64_t new_value)
nxm_execute_reg_move(const struct nx_action_reg_move *action,
struct flow *flow)
{
- /* Preparation. */
- int n_bits = ntohs(action->n_bits);
- uint64_t mask = n_bits == 64 ? UINT64_MAX : (UINT64_C(1) << n_bits) - 1;
+ ovs_be16 src_ofs_nbits, dst_ofs_nbits;
+ uint64_t src_data;
+ int n_bits;
- /* Get the interesting bits of the source field. */
- const struct nxm_field *src = nxm_field_lookup(ntohl(action->src));
- int src_ofs = ntohs(action->src_ofs);
- uint64_t src_data = (nxm_read_field(src, flow) >> src_ofs) & mask;
+ n_bits = ntohs(action->n_bits);
+ src_ofs_nbits = nxm_encode_ofs_nbits(ntohs(action->src_ofs), n_bits);
+ dst_ofs_nbits = nxm_encode_ofs_nbits(ntohs(action->dst_ofs), n_bits);
- nxm_reg_load(action->dst,
- nxm_encode_ofs_nbits(ntohs(action->dst_ofs), n_bits),
- src_data, flow);
+ src_data = nxm_read_field_bits(action->src, src_ofs_nbits, flow);
+ nxm_reg_load(action->dst, dst_ofs_nbits, src_data, flow);
}
void