freebsd-dev/sys/dev/netmap/netmap_kern.h
Luigi Rizzo 68b8534bdf Bring in support for netmap, a framework for very efficient packet
I/O from userspace, capable of line rate at 10G, see

	http://info.iet.unipi.it/~luigi/netmap/

At this time I am bringing in only the generic code (sys/dev/netmap/
plus two headers under sys/net/), and some sample applications in
tools/tools/netmap. There is also a manpage in share/man/man4 [1]

In order to make use of the framework you need to build a kernel
with "device netmap", and patch individual drivers with the code
that you can find in

	sys/dev/netmap/head.diff

The file will go away as the relevant pieces are committed to
the various device drivers, which should happen in a few days
after talking to the driver maintainers.

Netmap support is available at the moment for Intel 10G and 1G
cards (ixgbe, em/lem/igb), and for the Realtek 1G card ("re").
I have partial patches for "bge" and am starting to work on "cxgbe".
Hopefully changes are trivial enough so interested third parties
can submit their patches. Interested people can contact me
for advice on how to add netmap support to specific devices.

CREDITS:
    Netmap has been developed by Luigi Rizzo and other collaborators
    at the Universita` di Pisa, and supported by EU project CHANGE
    (http://www.change-project.eu/)
    The code is distributed under a BSD Copyright.

[1] In my opinion is a bad idea to have all manpage in one directory.
  We should place kernel documentation in the same dir that contains
  the code, which would make it much simpler to keep doc and code
  in sync, reduce the clutter in share/man/ and incidentally is
  the policy used for all of userspace code.
  Makefiles and doc tools can be trivially adjusted to find the
  manpages in the relevant subdirs.
2011-11-17 12:17:39 +00:00

222 lines
7.2 KiB
C

/*
* Copyright (C) 2011 Matteo Landi, Luigi Rizzo. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
/*
* $FreeBSD$
* $Id: netmap_kern.h 9662 2011-11-16 13:18:06Z luigi $
*
* The header contains the definitions of constants and function
* prototypes used only in kernelspace.
*/
#ifndef _NET_NETMAP_KERN_H_
#define _NET_NETMAP_KERN_H_
#ifdef MALLOC_DECLARE
MALLOC_DECLARE(M_NETMAP);
#endif
#define ND(format, ...)
#define D(format, ...) \
do { \
struct timeval __xxts; \
microtime(&__xxts); \
printf("%03d.%06d %s [%d] " format "\n",\
(int)__xxts.tv_sec % 1000, (int)__xxts.tv_usec, \
__FUNCTION__, __LINE__, ##__VA_ARGS__); \
} while (0)
struct netmap_adapter;
/*
* private, kernel view of a ring.
*
* XXX 20110627-todo
* The index in the NIC and netmap ring is offset by nkr_hwofs slots.
* This is so that, on a reset, buffers owned by userspace are not
* modified by the kernel. In particular:
* RX rings: the next empty buffer (hwcur + hwavail + hwofs) coincides
* the next empty buffer as known by the hardware (next_to_check or so).
* TX rings: hwcur + hwofs coincides with next_to_send
*/
struct netmap_kring {
struct netmap_ring *ring;
u_int nr_hwcur;
int nr_hwavail;
u_int nr_kflags;
u_int nkr_num_slots;
u_int nkr_hwofs; /* offset between NIC and netmap ring */
struct netmap_adapter *na; // debugging
struct selinfo si; /* poll/select wait queue */
};
/*
* This struct is part of and extends the 'struct adapter' (or
* equivalent) device descriptor. It contains all fields needed to
* support netmap operation.
*/
struct netmap_adapter {
int refcount; /* number of user-space descriptors using this
interface, which is equal to the number of
struct netmap_if objs in the mapped region. */
int separate_locks; /* set if the interface suports different
locks for rx, tx and core. */
u_int num_queues; /* number of tx/rx queue pairs: this is
a duplicate field needed to simplify the
signature of ``netmap_detach``. */
u_int num_tx_desc; /* number of descriptor in each queue */
u_int num_rx_desc;
u_int buff_size;
u_int flags; /* NR_REINIT */
/* tx_rings and rx_rings are private but allocated
* as a contiguous chunk of memory. Each array has
* N+1 entries, for the adapter queues and for the host queue.
*/
struct netmap_kring *tx_rings; /* array of TX rings. */
struct netmap_kring *rx_rings; /* array of RX rings. */
/* copy of if_qflush and if_transmit pointers, to intercept
* packets from the network stack when netmap is active.
* XXX probably if_qflush is not necessary.
*/
void (*if_qflush)(struct ifnet *);
int (*if_transmit)(struct ifnet *, struct mbuf *);
/* references to the ifnet and device routines, used by
* the generic netmap functions.
*/
struct ifnet *ifp; /* adapter is ifp->if_softc */
int (*nm_register)(struct ifnet *, int onoff);
void (*nm_lock)(void *, int what, u_int ringid);
int (*nm_txsync)(void *, u_int ring, int lock);
int (*nm_rxsync)(void *, u_int ring, int lock);
};
/*
* The combination of "enable" (ifp->if_capabilities &IFCAP_NETMAP)
* and refcount gives the status of the interface, namely:
*
* enable refcount Status
*
* FALSE 0 normal operation
* FALSE != 0 -- (impossible)
* TRUE 1 netmap mode
* TRUE 0 being deleted.
*/
#define NETMAP_DELETING(_na) ( ((_na)->refcount == 0) && \
( (_na)->ifp->if_capenable & IFCAP_NETMAP) )
/*
* parameters for (*nm_lock)(adapter, what, index)
*/
enum {
NETMAP_NO_LOCK = 0,
NETMAP_CORE_LOCK, NETMAP_CORE_UNLOCK,
NETMAP_TX_LOCK, NETMAP_TX_UNLOCK,
NETMAP_RX_LOCK, NETMAP_RX_UNLOCK,
};
/*
* The following are support routines used by individual drivers to
* support netmap operation.
*
* netmap_attach() initializes a struct netmap_adapter, allocating the
* struct netmap_ring's and the struct selinfo.
*
* netmap_detach() frees the memory allocated by netmap_attach().
*
* netmap_start() replaces the if_transmit routine of the interface,
* and is used to intercept packets coming from the stack.
*
* netmap_load_map/netmap_reload_map are helper routines to set/reset
* the dmamap for a packet buffer
*
* netmap_reset() is a helper routine to be called in the driver
* when reinitializing a ring.
*/
int netmap_attach(struct netmap_adapter *, int);
void netmap_detach(struct ifnet *);
int netmap_start(struct ifnet *, struct mbuf *);
enum txrx { NR_RX = 0, NR_TX = 1 };
struct netmap_slot *netmap_reset(struct netmap_adapter *na,
enum txrx tx, int n, u_int new_cur);
void netmap_load_map(bus_dma_tag_t tag, bus_dmamap_t map,
void *buf, bus_size_t buflen);
void netmap_reload_map(bus_dma_tag_t tag, bus_dmamap_t map,
void *buf, bus_size_t buflen);
int netmap_ring_reinit(struct netmap_kring *);
/*
* XXX eventually, get rid of netmap_total_buffers and netmap_buffer_base
* in favour of the structure
*/
// struct netmap_buf_pool;
// extern struct netmap_buf_pool nm_buf_pool;
extern u_int netmap_total_buffers;
extern char *netmap_buffer_base;
extern int netmap_verbose; // XXX debugging
enum { /* verbose flags */
NM_VERB_ON = 1, /* generic verbose */
NM_VERB_HOST = 0x2, /* verbose host stack */
NM_VERB_RXSYNC = 0x10, /* verbose on rxsync/txsync */
NM_VERB_TXSYNC = 0x20,
NM_VERB_RXINTR = 0x100, /* verbose on rx/tx intr (driver) */
NM_VERB_TXINTR = 0x200,
NM_VERB_NIC_RXSYNC = 0x1000, /* verbose on rx/tx intr (driver) */
NM_VERB_NIC_TXSYNC = 0x2000,
};
/*
* return a pointer to the struct netmap adapter from the ifp
*/
#define NA(_ifp) ((struct netmap_adapter *)(_ifp)->if_pspare[0])
/*
* return the address of a buffer.
* XXX this is a special version with hardwired 2k bufs
* On error return netmap_buffer_base which is detected as a bad pointer.
*/
static inline char *
NMB(struct netmap_slot *slot)
{
uint32_t i = slot->buf_idx;
return (i >= netmap_total_buffers) ? netmap_buffer_base :
#if NETMAP_BUF_SIZE == 2048
netmap_buffer_base + (i << 11);
#else
netmap_buffer_base + (i *NETMAP_BUF_SIZE);
#endif
}
#endif /* _NET_NETMAP_KERN_H_ */