ofp-parse: Allow match field names in actions and brackets in matches.

Allow using match field names in addition to the canonical register
names in actions (including 'load', 'move', 'push', 'pop', 'output',
'multipath', 'bundle_load', and 'learn').  Allow also leaving out the
trailing '[]' to indicate full field.  These changes allow simpler
syntax similar to 'set_field' to be used also elsewhere.

Correspondingly, allow the '[start..end]' syntax to be used in matches
in addition to the more explicit 'value/mask' notation.  For example,
to match on the value 2 of the bits 14..15 of NXM_NX_REG0, the match
could include:

... reg0[14..15]=2 ...

instead of

... reg0=0x8000/0xc000 ...

Note that only contiguous masks can be specified with the bracket
notation.

Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Acked-by: Ben Pfaff <blp@ovn.org>

1 files changed, 26 insertions, 19 deletions

diff --git a/utilities/ovs-ofctl.8.in b/utilities/ovs-ofctl.8.in
index 49b3aa5f7..d8c03db75 100644
--- a/utilities/ovs-ofctl.8.in
+++ b/utilities/ovs-ofctl.8.in
@@ -1545,8 +1545,8 @@ is the packet's input port, the packet is not output.
 .
 .IP \fBoutput:\fIsrc\fB[\fIstart\fB..\fIend\fB]
 Outputs the packet to the OpenFlow port number read from \fIsrc\fR,
-which must be an NXM field as described above.  For example,
-\fBoutput:NXM_NX_REG0[16..31]\fR outputs to the OpenFlow port number
+which may be an NXM field name, as described above, or a match field name.
+\fBoutput:reg0[16..31]\fR outputs to the OpenFlow port number
 written in the upper half of register 0.  If the port number is the
 packet's input port, the packet is not output.
 .IP
@@ -2014,18 +2014,19 @@ bytes with value 0 to make the total number 6 more than a multiple of
 .
 .IP "\fBmove:\fIsrc\fB[\fIstart\fB..\fIend\fB]\->\fIdst\fB[\fIstart\fB..\fIend\fB]\fR"
 Copies the named bits from field \fIsrc\fR to field \fIdst\fR.
-\fIsrc\fR and \fIdst\fR must be NXM field names as defined in
-\fBnicira\-ext.h\fR, e.g. \fBNXM_OF_UDP_SRC\fR or \fBNXM_NX_REG0\fR.
-Each \fIstart\fR and \fIend\fR pair, which are inclusive, must specify
-the same number of bits and must fit within its respective field.
+\fIsrc\fR and \fIdst\fR may be NXM field names as defined in
+\fBnicira\-ext.h\fR, e.g. \fBNXM_OF_UDP_SRC\fR or \fBNXM_NX_REG0\fR,
+or a match field name, e.g. \fBreg0\fR.  Each
+\fIstart\fR and \fIend\fR pair, which are inclusive, must specify the
+same number of bits and must fit within its respective field.
 Shorthands for \fB[\fIstart\fB..\fIend\fB]\fR exist: use
 \fB[\fIbit\fB]\fR to specify a single bit or \fB[]\fR to specify an
-entire field.
+entire field (in the latter case the brackets can also be left off).
 .IP
 Examples: \fBmove:NXM_NX_REG0[0..5]\->NXM_NX_REG1[26..31]\fR copies the
 six bits numbered 0 through 5, inclusive, in register 0 into bits 26
 through 31, inclusive;
-\fBmove:NXM_NX_REG0[0..15]\->NXM_OF_VLAN_TCI[]\fR copies the least
+\fBmove:reg0[0..15]\->vlan_tci\fR copies the least
 significant 16 bits of register 0 into the VLAN TCI field.
 .IP
 In OpenFlow 1.0 through 1.4, \fBmove\fR ordinarily uses an Open
@@ -2044,9 +2045,9 @@ the customary syntax for field \fIdst\fR, which is expressed as a
 field name.  For example, \fBset_field:00:11:22:33:44:55->eth_src\fR
 sets the Ethernet source address to 00:11:22:33:44:55.  With
 \fBload\fR, \fIvalue\fR must be an integer value (in decimal or
-prefixed by \fB0x\fR for hexadecimal) and \fIdst\fR is the NXM or OXM
-name for the field.  For example,
-\fBload:0x001122334455->OXM_OF_ETH_DST[]\fR has the same effect as the
+prefixed by \fB0x\fR for hexadecimal) and \fIdst\fR can also be the
+NXM or OXM name for the field.  For example,
+\fBload:0x001122334455->OXM_OF_ETH_SRC[]\fR has the same effect as the
 prior \fBset_field\fR example.
 .IP
 The two forms exist for historical reasons.  Open vSwitch 1.1
@@ -2066,8 +2067,9 @@ subfield, \fBOFPAT_SET_FIELD\fR otherwise; and OpenFlow 1.5 and later,
 Pushes \fIstart\fR to \fIend\fR bits inclusive, in fields
 on top of the stack.
 .IP
-Example: \fBpush:NXM_NX_REG2[0..5]\fR push the value stored in register
-2 bits 0 through 5, inclusive, on to the internal stack.
+Example: \fBpush:NXM_NX_REG2[0..5]\fR or \fBpush:reg2[0..5]\fR push
+the value stored in register 2 bits 0 through 5, inclusive, on to the
+internal stack.
 .
 .IP "\fBpop:\fIdst\fB[\fIstart\fB..\fIend\fB]"
 Pops from the top of the stack, retrieves the \fIstart\fR to \fIend\fR bits
@@ -2075,9 +2077,9 @@ inclusive, from the value popped and store them into the corresponding
 bits in \fIdst\fR.
 .
 .IP
-Example: \fBpop:NXM_NX_REG2[0..5]\fR pops the value from top of the stack.
-Set register 2 bits 0 through 5, inclusive, based on bits 0 through 5 from the
-value just popped.
+Example: \fBpop:NXM_NX_REG2[0..5]\fR or \fBpop:reg2[0..5]\fR pops the
+value from top of the stack.  Set register 2 bits 0 through 5,
+inclusive, based on bits 0 through 5 from the value just popped.
 .
 .
 .IP "\fBmultipath(\fIfields\fB, \fIbasis\fB, \fIalgorithm\fB, \fIn_links\fB, \fIarg\fB, \fIdst\fB[\fIstart\fB..\fIend\fB])\fR"
@@ -2144,7 +2146,10 @@ above.
 Example: \fBbundle_load(eth_src, 0, hrw, ofport, NXM_NX_REG0[],
 slaves:4, 8)\fR uses an Ethernet source hash with basis 0, to select
 between OpenFlow ports 4 and 8 using the Highest Random Weight
-algorithm, and writes the selection to \fBNXM_NX_REG0[]\fR.
+algorithm, and writes the selection to \fBNXM_NX_REG0[]\fR.  Also the
+match field name can be used, for example, instead of 'NXM_NX_REG0'
+the name 'reg0' can be used.  When the while field is indicated the
+empty brackets can also be left off.
 .IP
 Refer to \fBnicira\-ext.h\fR for more details.
 .
@@ -3287,8 +3292,10 @@ Implements a level 2 MAC learning switch using the learn.
 \fBovs\-ofctl add\-flow br0 'table=0,priority=0 actions=load:3->NXM_NX_REG0[0..15],learn(table=0,priority=1,idle_timeout=10,NXM_OF_ETH_SRC[],NXM_OF_VLAN_TCI[0..11],output:NXM_NX_REG0[0..15]),output:2\fR
 In this use of a learn action, the first packet from each source MAC
 will be sent to port 2. Subsequent packets will be output to port 3,
-with an idle timeout of 10 seconds.
-.
+with an idle timeout of 10 seconds.  NXM field names and match field
+names are both accepted, e.g. \fBNXM_NX_REG0\fR or \fBreg0\fR for the
+first register, and empty brackets may be omitted.
+.IP
 Additional examples may be found documented as part of related sections.
 .
 .SH "SEE ALSO"