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Index: head/share/man/man4/netmap.4
===================================================================
--- head/share/man/man4/netmap.4
+++ head/share/man/man4/netmap.4
@@ -27,17 +27,12 @@
.\"
.\" $FreeBSD$
.\"
-.Dd October 28, 2018
+.Dd November 20, 2018
.Dt NETMAP 4
.Os
.Sh NAME
.Nm netmap
.Nd a framework for fast packet I/O
-.Nm VALE
-.Nd a fast VirtuAl Local Ethernet using the netmap API
-.Pp
-.Nm netmap pipes
-.Nd a shared memory packet transport channel
.Sh SYNOPSIS
.Cd device netmap
.Sh DESCRIPTION
@@ -79,7 +74,7 @@
35-40 Mpps on 40 Gbit/s NICs (limited by the hardware);
about 20 Mpps per core for VALE ports;
and over 100 Mpps for
-.Nm netmap pipes.
+.Nm netmap pipes .
NICs without native
.Nm
support can still use the API in emulated mode,
@@ -108,9 +103,9 @@
and standard OS mechanisms such as
.Xr select 2 ,
.Xr poll 2 ,
-.Xr epoll 2 ,
+.Xr kqueue 2
and
-.Xr kqueue 2 .
+.Xr epoll 7 .
All types of
.Nm netmap ports
and the
@@ -218,12 +213,6 @@
and
.Xr poll 2
on the file descriptor permit blocking I/O.
-.Xr epoll 2
-and
-.Xr kqueue 2
-are not supported on
-.Nm
-file descriptors.
.Pp
While a NIC is in
.Nm
@@ -244,7 +233,7 @@
API.
The main structures and fields are indicated below:
.Bl -tag -width XXX
-.It Dv struct netmap_if (one per interface)
+.It Dv struct netmap_if (one per interface )
.Bd -literal
struct netmap_if {
...
@@ -267,14 +256,30 @@
.Em NIOCREGIF
can also request additional unbound buffers in the same memory space,
to be used as temporary storage for packets.
+The number of extra
+buffers is specified in the
+.Va arg.nr_arg3
+field.
+On success, the kernel writes back to
+.Va arg.nr_arg3
+the number of extra buffers actually allocated (they may be less
+than the amount requested if the memory space ran out of buffers).
.Pa ni_bufs_head
-contains the index of the first of these free rings,
+contains the index of the first of these extra buffers,
which are connected in a list (the first uint32_t of each
buffer being the index of the next buffer in the list).
A
.Dv 0
indicates the end of the list.
-.It Dv struct netmap_ring (one per ring)
+The application is free to modify
+this list and use the buffers (i.e., binding them to the slots of a
+netmap ring).
+When closing the netmap file descriptor,
+the kernel frees the buffers contained in the list pointed by
+.Pa ni_bufs_head
+, irrespectively of the buffers originally provided by the kernel on
+.Em NIOCREGIF .
+.It Dv struct netmap_ring (one per ring )
.Bd -literal
struct netmap_ring {
...
@@ -296,7 +301,7 @@
pointers, metadata and an array of
.Em slots
describing the buffers.
-.It Dv struct netmap_slot (one per buffer)
+.It Dv struct netmap_slot (one per buffer )
.Bd -literal
struct netmap_slot {
uint32_t buf_idx; /* buffer index */
@@ -371,7 +376,6 @@
The only exception are slots (and buffers) in the range
.Va tail\ . . . head-1 ,
that are explicitly assigned to the kernel.
-.Pp
.Ss TRANSMIT RINGS
On transmit rings, after a
.Nm
@@ -498,10 +502,9 @@
This flag helps detect
when packets have been sent and a file descriptor can be closed.
.It NS_FORWARD
-When a ring is in 'transparent' mode (see
-.Sx TRANSPARENT MODE ) ,
-packets marked with this flag are forwarded to the other endpoint
-at the next system call, thus restoring (in a selective way)
+When a ring is in 'transparent' mode,
+packets marked with this flag by the user application are forwarded to the
+other endpoint at the next system call, thus restoring (in a selective way)
the connection between a NIC and the host stack.
.It NS_NO_LEARN
tells the forwarding code that the source MAC address for this
@@ -669,7 +672,7 @@
On return the pipe
will only have a single ring pair with index 0,
irrespective of the value of
-.Va i.
+.Va i .
.El
.Pp
By default, a
@@ -681,11 +684,14 @@
The feature can be disabled by or-ing
.Va NETMAP_NO_TX_POLL
to the value written to
-.Va nr_ringid.
+.Va nr_ringid .
When this feature is used,
packets are transmitted only on
.Va ioctl(NIOCTXSYNC)
-or select()/poll() are called with a write event (POLLOUT/wfdset) or a full ring.
+or
+.Va select() /
+.Va poll()
+are called with a write event (POLLOUT/wfdset) or a full ring.
.Pp
When registering a virtual interface that is dynamically created to a
.Xr vale 4
@@ -698,7 +704,7 @@
tells the hardware of consumed packets, and asks for newly available
packets.
.El
-.Sh SELECT, POLL, EPOLL, KQUEUE.
+.Sh SELECT, POLL, EPOLL, KQUEUE
.Xr select 2
and
.Xr poll 2
@@ -712,7 +718,7 @@
Both block if no slots are available in the ring
.Va ( ring->cur == ring->tail ) .
Depending on the platform,
-.Xr epoll 2
+.Xr epoll 7
and
.Xr kqueue 2
are supported too.
@@ -731,7 +737,10 @@
.Dv NETMAP_DO_RX_POLL
flag to
.Em NIOCREGIF updates receive rings even without read events.
-Note that on epoll and kqueue,
+Note that on
+.Xr epoll 7
+and
+.Xr kqueue 2 ,
.Dv NETMAP_NO_TX_POLL
and
.Dv NETMAP_DO_RX_POLL
@@ -759,9 +768,9 @@
.Pp
The following functions are available:
.Bl -tag -width XXXXX
-.It Va struct nm_desc * nm_open(const char *ifname, const struct nmreq *req, uint64_t flags, const struct nm_desc *arg)
+.It Va struct nm_desc * nm_open(const char *ifname, const struct nmreq *req, uint64_t flags, const struct nm_desc *arg )
similar to
-.Xr pcap_open 3pcap ,
+.Xr pcap_open_live 3 ,
binds a file descriptor to a port.
.Bl -tag -width XX
.It Va ifname
@@ -782,44 +791,50 @@
.Va NETMAP_NO_TX_POLL ,
.Va NETMAP_DO_RX_POLL
(copied into nr_ringid);
-.Va NM_OPEN_NO_MMAP (if arg points to the same memory region,
+.Va NM_OPEN_NO_MMAP
+(if arg points to the same memory region,
avoids the mmap and uses the values from it);
-.Va NM_OPEN_IFNAME (ignores ifname and uses the values in arg);
+.Va NM_OPEN_IFNAME
+(ignores ifname and uses the values in arg);
.Va NM_OPEN_ARG1 ,
.Va NM_OPEN_ARG2 ,
-.Va NM_OPEN_ARG3 (uses the fields from arg);
-.Va NM_OPEN_RING_CFG (uses the ring number and sizes from arg).
+.Va NM_OPEN_ARG3
+(uses the fields from arg);
+.Va NM_OPEN_RING_CFG
+(uses the ring number and sizes from arg).
.El
-.It Va int nm_close(struct nm_desc *d)
+.It Va int nm_close(struct nm_desc *d )
closes the file descriptor, unmaps memory, frees resources.
-.It Va int nm_inject(struct nm_desc *d, const void *buf, size_t size)
-similar to pcap_inject(), pushes a packet to a ring, returns the size
+.It Va int nm_inject(struct nm_desc *d, const void *buf, size_t size )
+similar to
+.Va pcap_inject() ,
+pushes a packet to a ring, returns the size
of the packet is successful, or 0 on error;
-.It Va int nm_dispatch(struct nm_desc *d, int cnt, nm_cb_t cb, u_char *arg)
-similar to pcap_dispatch(), applies a callback to incoming packets
-.It Va u_char * nm_nextpkt(struct nm_desc *d, struct nm_pkthdr *hdr)
-similar to pcap_next(), fetches the next packet
+.It Va int nm_dispatch(struct nm_desc *d, int cnt, nm_cb_t cb, u_char *arg )
+similar to
+.Va pcap_dispatch() ,
+applies a callback to incoming packets
+.It Va u_char * nm_nextpkt(struct nm_desc *d, struct nm_pkthdr *hdr )
+similar to
+.Va pcap_next() ,
+fetches the next packet
.El
.Sh SUPPORTED DEVICES
.Nm
natively supports the following devices:
.Pp
-On FreeBSD:
+On
+.Fx :
.Xr cxgbe 4 ,
.Xr em 4 ,
-.Xr igb 4 ,
+.Xr iflib 4
+(providing igb, em and lem),
.Xr ixgbe 4 ,
.Xr ixl 4 ,
-.Xr lem 4 ,
-.Xr re 4 .
+.Xr re 4 ,
+.Xr vtnet 4 .
.Pp
-On Linux
-.Xr e1000 4 ,
-.Xr e1000e 4 ,
-.Xr i40e 4 ,
-.Xr igb 4 ,
-.Xr ixgbe 4 ,
-.Xr r8169 4 .
+On Linux e1000, e1000e, i40e, igb, ixgbe, ixgbevf, r8169, virtio_net, vmxnet3.
.Pp
NICs without native support can still be used in
.Nm
@@ -848,10 +863,11 @@
.Sh SYSCTL VARIABLES AND MODULE PARAMETERS
Some aspect of the operation of
.Nm
-are controlled through sysctl variables on FreeBSD
+are controlled through sysctl variables on
+.Fx
.Em ( dev.netmap.* )
and module parameters on Linux
-.Em ( /sys/module/netmap_lin/parameters/* ) :
+.Em ( /sys/module/netmap/parameters/* ) :
.Bl -tag -width indent
.It Va dev.netmap.admode: 0
Controls the use of native or emulated adapter mode.
@@ -861,6 +877,8 @@
1 forces native mode and fails if not available;
.Pp
2 forces emulated hence never fails.
+.It Va dev.netmap.generic_rings: 1
+Number of rings used for emulated netmap mode
.It Va dev.netmap.generic_ringsize: 1024
Ring size used for emulated netmap mode
.It Va dev.netmap.generic_mit: 100000
@@ -902,13 +920,15 @@
switch.
Values above 64 generally guarantee good
performance.
+.It Va dev.netmap.ptnet_vnet_hdr: 1
+Allow ptnet devices to use virtio-net headers
.El
.Sh SYSTEM CALLS
.Nm
uses
.Xr select 2 ,
.Xr poll 2 ,
-.Xr epoll 2
+.Xr epoll 7
and
.Xr kqueue 2
to wake up processes when significant events occur, and
@@ -1077,6 +1097,7 @@
.Xr vale-ctl 4 ,
.Xr bridge 8 ,
.Xr lb 8 ,
+.Xr nmreplay 8 ,
.Xr pkt-gen 8
.Pp
.Pa http://info.iet.unipi.it/~luigi/netmap/

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