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freebsd/sys/dev/netmap/netmap_kern.h
Luigi Rizzo ce3ee1e7c4 update to the latest netmap snapshot.
This includes the following:
- use separate memory regions for VALE ports
- locking fixes
- some simplifications in the NIC-specific routines
- performance improvements for the VALE switch
- some new features in the pkt-gen test program
- documentation updates

There are small API changes that require programs to be recompiled
(NETMAP_API has been bumped so you will detect old binaries at runtime).

In particular:
- struct netmap_slot now is 16 bytes to support an extra pointer,
  which may save one data copy when using VALE ports or VMs;
- the struct netmap_if has two extra fields;

MFC after:	3 days
2013-11-01 21:21:14 +00:00

711 lines
22 KiB
C

/*
* Copyright (C) 2011-2013 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.
*/
/*
* $FreeBSD$
*
* The header contains the definitions of constants and function
* prototypes used only in kernelspace.
*/
#ifndef _NET_NETMAP_KERN_H_
#define _NET_NETMAP_KERN_H_
#if defined(__FreeBSD__)
#define likely(x) __builtin_expect((long)!!(x), 1L)
#define unlikely(x) __builtin_expect((long)!!(x), 0L)
#define NM_LOCK_T struct mtx
#define NM_SELINFO_T struct selinfo
#define MBUF_LEN(m) ((m)->m_pkthdr.len)
#define NM_SEND_UP(ifp, m) ((ifp)->if_input)(ifp, m)
#define NM_ATOMIC_T volatile int
#elif defined (linux)
#define NM_LOCK_T safe_spinlock_t // see bsd_glue.h
#define NM_SELINFO_T wait_queue_head_t
#define MBUF_LEN(m) ((m)->len)
#define NM_SEND_UP(ifp, m) netif_rx(m)
#define NM_ATOMIC_T volatile long unsigned int
#ifndef DEV_NETMAP
#define DEV_NETMAP
#endif /* DEV_NETMAP */
/*
* IFCAP_NETMAP goes into net_device's priv_flags (if_capenable).
* This was 16 bits up to linux 2.6.36, so we need a 16 bit value on older
* platforms and tolerate the clash with IFF_DYNAMIC and IFF_BRIDGE_PORT.
* For the 32-bit value, 0x100000 has no clashes until at least 3.5.1
*/
#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,37)
#define IFCAP_NETMAP 0x8000
#else
#define IFCAP_NETMAP 0x200000
#endif
#elif defined (__APPLE__)
#warning apple support is incomplete.
#define likely(x) __builtin_expect(!!(x), 1)
#define unlikely(x) __builtin_expect(!!(x), 0)
#define NM_LOCK_T IOLock *
#define NM_SELINFO_T struct selinfo
#define MBUF_LEN(m) ((m)->m_pkthdr.len)
#define NM_SEND_UP(ifp, m) ((ifp)->if_input)(ifp, m)
#else
#error unsupported platform
#endif /* end - platform-specific code */
#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)
/* rate limited, lps indicates how many per second */
#define RD(lps, format, ...) \
do { \
static int t0, __cnt; \
if (t0 != time_second) { \
t0 = time_second; \
__cnt = 0; \
} \
if (__cnt++ < lps) \
D(format, ##__VA_ARGS__); \
} while (0)
struct netmap_adapter;
struct nm_bdg_fwd;
struct nm_bridge;
struct netmap_priv_d;
const char *nm_dump_buf(char *p, int len, int lim, char *dst);
/*
* private, kernel view of a ring. Keeps track of the status of
* a ring across system calls.
*
* nr_hwcur index of the next buffer to refill.
* It corresponds to ring->cur - ring->reserved
*
* nr_hwavail the number of slots "owned" by userspace.
* nr_hwavail =:= ring->avail + ring->reserved
*
* The indexes in the NIC and netmap rings are 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 with
* the next empty buffer as known by the hardware (next_to_check or so).
* TX rings: hwcur + hwofs coincides with next_to_send
*
* Clients cannot issue concurrent syscall on a ring. The system
* detects this and reports an error using two flags,
* NKR_WBUSY and NKR_RBUSY
* For received packets, slot->flags is set to nkr_slot_flags
* so we can provide a proper initial value (e.g. set NS_FORWARD
* when operating in 'transparent' mode).
*
* The following fields are used to implement lock-free copy of packets
* from input to output ports in VALE switch:
* nkr_hwlease buffer after the last one being copied.
* A writer in nm_bdg_flush reserves N buffers
* from nr_hwlease, advances it, then does the
* copy outside the lock.
* In RX rings (used for VALE ports),
* nkr_hwcur + nkr_hwavail <= nkr_hwlease < nkr_hwcur+N-1
* In TX rings (used for NIC or host stack ports)
* nkr_hwcur <= nkr_hwlease < nkr_hwcur+ nkr_hwavail
* nkr_leases array of nkr_num_slots where writers can report
* completion of their block. NR_NOSLOT (~0) indicates
* that the writer has not finished yet
* nkr_lease_idx index of next free slot in nr_leases, to be assigned
*
* The kring is manipulated by txsync/rxsync and generic netmap function.
* q_lock is used to arbitrate access to the kring from within the netmap
* code, and this and other protections guarantee that there is never
* more than 1 concurrent call to txsync or rxsync. So we are free
* to manipulate the kring from within txsync/rxsync without any extra
* locks.
*/
struct netmap_kring {
struct netmap_ring *ring;
uint32_t nr_hwcur;
uint32_t nr_hwavail;
uint32_t nr_kflags; /* private driver flags */
#define NKR_PENDINTR 0x1 // Pending interrupt.
uint32_t nkr_num_slots;
int32_t nkr_hwofs; /* offset between NIC and netmap ring */
uint16_t nkr_slot_flags; /* initial value for flags */
struct netmap_adapter *na;
struct nm_bdg_fwd *nkr_ft;
uint32_t *nkr_leases;
#define NR_NOSLOT ((uint32_t)~0)
uint32_t nkr_hwlease;
uint32_t nkr_lease_idx;
NM_SELINFO_T si; /* poll/select wait queue */
NM_LOCK_T q_lock; /* protects kring and ring. */
NM_ATOMIC_T nr_busy; /* prevent concurrent syscalls */
volatile int nkr_stopped;
} __attribute__((__aligned__(64)));
/* return the next index, with wraparound */
static inline uint32_t
nm_next(uint32_t i, uint32_t lim)
{
return unlikely (i == lim) ? 0 : i + 1;
}
/*
*
* Here is the layout for the Rx and Tx rings.
RxRING TxRING
+-----------------+ +-----------------+
| | | |
|XXX free slot XXX| |XXX free slot XXX|
+-----------------+ +-----------------+
| |<-hwcur | |<-hwcur
| reserved h | | (ready |
+----------- w -+ | to be |
cur->| a | | sent) h |
| v | +---------- w |
| a | cur->| (being a |
| i | | prepared) v |
| avail l | | a |
+-----------------+ + a ------ i +
| | ... | v l |<-hwlease
| (being | ... | a | ...
| prepared) | ... | i | ...
+-----------------+ ... | l | ...
| |<-hwlease +-----------------+
| | | |
| | | |
| | | |
| | | |
+-----------------+ +-----------------+
* The cur/avail (user view) and hwcur/hwavail (kernel view)
* are used in the normal operation of the card.
*
* When a ring is the output of a switch port (Rx ring for
* a VALE port, Tx ring for the host stack or NIC), slots
* are reserved in blocks through 'hwlease' which points
* to the next unused slot.
* On an Rx ring, hwlease is always after hwavail,
* and completions cause avail to advance.
* On a Tx ring, hwlease is always between cur and hwavail,
* and completions cause cur to advance.
*
* nm_kr_space() returns the maximum number of slots that
* can be assigned.
* nm_kr_lease() reserves the required number of buffers,
* advances nkr_hwlease and also returns an entry in
* a circular array where completions should be reported.
*/
/*
* This struct extends the 'struct adapter' (or
* equivalent) device descriptor. It contains all fields needed to
* support netmap operation.
*/
struct netmap_adapter {
/*
* On linux we do not have a good way to tell if an interface
* is netmap-capable. So we use the following trick:
* NA(ifp) points here, and the first entry (which hopefully
* always exists and is at least 32 bits) contains a magic
* value which we can use to detect that the interface is good.
*/
uint32_t magic;
uint32_t na_flags; /* future place for IFCAP_NETMAP */
#define NAF_SKIP_INTR 1 /* use the regular interrupt handler.
* useful during initialization
*/
#define NAF_SW_ONLY 2 /* forward packets only to sw adapter */
#define NAF_BDG_MAYSLEEP 4 /* the bridge is allowed to sleep when
* forwarding packets coming from this
* interface
*/
#define NAF_MEM_OWNER 8 /* the adapter is responsible for the
* deallocation of the memory allocator
*/
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. */
/*
* The selwakeup in the interrupt thread can use per-ring
* and/or global wait queues. We track how many clients
* of each type we have so we can optimize the drivers,
* and especially avoid huge contention on the locks.
*/
int na_single; /* threads attached to a single hw queue */
int na_multi; /* threads attached to multiple hw queues */
u_int num_rx_rings; /* number of adapter receive rings */
u_int num_tx_rings; /* number of adapter transmit rings */
u_int num_tx_desc; /* number of descriptor in each queue */
u_int num_rx_desc;
/* 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. */
NM_SELINFO_T tx_si, rx_si; /* global wait queues */
/* copy of if_qflush and if_transmit pointers, to intercept
* packets from the network stack when netmap is active.
*/
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 */
NM_LOCK_T core_lock; /* used if no device lock available */
int (*nm_register)(struct ifnet *, int onoff);
int (*nm_txsync)(struct ifnet *, u_int ring, int flags);
int (*nm_rxsync)(struct ifnet *, u_int ring, int flags);
#define NAF_FORCE_READ 1
#define NAF_FORCE_RECLAIM 2
/* return configuration information */
int (*nm_config)(struct ifnet *, u_int *txr, u_int *txd,
u_int *rxr, u_int *rxd);
/*
* Bridge support:
*
* bdg_port is the port number used in the bridge;
* na_bdg_refcount is a refcount used for bridge ports,
* when it goes to 0 we can detach+free this port
* (a bridge port is always attached if it exists;
* it is not always registered)
* na_bdg points to the bridge this NA is attached to.
*/
int bdg_port;
int na_bdg_refcount;
struct nm_bridge *na_bdg;
/* When we attach a physical interface to the bridge, we
* allow the controlling process to terminate, so we need
* a place to store the netmap_priv_d data structure.
* This is only done when physical interfaces are attached to a bridge.
*/
struct netmap_priv_d *na_kpriv;
/* memory allocator */
struct netmap_mem_d *nm_mem;
#ifdef linux
struct net_device_ops nm_ndo;
#endif /* linux */
};
/*
* Available space in the ring.
*/
static inline uint32_t
nm_kr_space(struct netmap_kring *k, int is_rx)
{
int space;
if (is_rx) {
int busy = k->nkr_hwlease - k->nr_hwcur;
if (busy < 0)
busy += k->nkr_num_slots;
space = k->nkr_num_slots - 1 - busy;
} else {
space = k->nr_hwcur + k->nr_hwavail - k->nkr_hwlease;
if (space < 0)
space += k->nkr_num_slots;
}
#if 0
// sanity check
if (k->nkr_hwlease >= k->nkr_num_slots ||
k->nr_hwcur >= k->nkr_num_slots ||
k->nr_hwavail >= k->nkr_num_slots ||
busy < 0 ||
busy >= k->nkr_num_slots) {
D("invalid kring, cur %d avail %d lease %d lease_idx %d lim %d", k->nr_hwcur, k->nr_hwavail, k->nkr_hwlease,
k->nkr_lease_idx, k->nkr_num_slots);
}
#endif
return space;
}
/* return update position */
static inline uint32_t
nm_kr_rxpos(struct netmap_kring *k)
{
uint32_t pos = k->nr_hwcur + k->nr_hwavail;
if (pos >= k->nkr_num_slots)
pos -= k->nkr_num_slots;
#if 0
if (pos >= k->nkr_num_slots ||
k->nkr_hwlease >= k->nkr_num_slots ||
k->nr_hwcur >= k->nkr_num_slots ||
k->nr_hwavail >= k->nkr_num_slots ||
k->nkr_lease_idx >= k->nkr_num_slots) {
D("invalid kring, cur %d avail %d lease %d lease_idx %d lim %d", k->nr_hwcur, k->nr_hwavail, k->nkr_hwlease,
k->nkr_lease_idx, k->nkr_num_slots);
}
#endif
return pos;
}
/* make a lease on the kring for N positions. return the
* lease index
*/
static inline uint32_t
nm_kr_lease(struct netmap_kring *k, u_int n, int is_rx)
{
uint32_t lim = k->nkr_num_slots - 1;
uint32_t lease_idx = k->nkr_lease_idx;
k->nkr_leases[lease_idx] = NR_NOSLOT;
k->nkr_lease_idx = nm_next(lease_idx, lim);
if (n > nm_kr_space(k, is_rx)) {
D("invalid request for %d slots", n);
panic("x");
}
/* XXX verify that there are n slots */
k->nkr_hwlease += n;
if (k->nkr_hwlease > lim)
k->nkr_hwlease -= lim + 1;
if (k->nkr_hwlease >= k->nkr_num_slots ||
k->nr_hwcur >= k->nkr_num_slots ||
k->nr_hwavail >= k->nkr_num_slots ||
k->nkr_lease_idx >= k->nkr_num_slots) {
D("invalid kring %s, cur %d avail %d lease %d lease_idx %d lim %d",
k->na->ifp->if_xname,
k->nr_hwcur, k->nr_hwavail, k->nkr_hwlease,
k->nkr_lease_idx, k->nkr_num_slots);
}
return lease_idx;
}
/*
* XXX NETMAP_DELETING() is unused
*
* The combination of "enable" (ifp->if_capenable & 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) )
/*
* 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_transmit() 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 *, u_int);
void netmap_detach(struct ifnet *);
int netmap_transmit(struct ifnet *, struct mbuf *);
enum txrx { NR_RX = 0, NR_TX = 1 };
struct netmap_slot *netmap_reset(struct netmap_adapter *na,
enum txrx tx, u_int n, u_int new_cur);
int netmap_ring_reinit(struct netmap_kring *);
u_int nm_bound_var(u_int *v, u_int dflt, u_int lo, u_int hi, const char *msg);
/*
* The following bridge-related interfaces are used by other kernel modules
* In the version that only supports unicast or broadcast, the lookup
* function can return 0 .. NM_BDG_MAXPORTS-1 for regular ports,
* NM_BDG_MAXPORTS for broadcast, NM_BDG_MAXPORTS+1 for unknown.
* XXX in practice "unknown" might be handled same as broadcast.
*/
typedef u_int (*bdg_lookup_fn_t)(char *buf, u_int len, uint8_t *ring_nr,
struct netmap_adapter *);
int netmap_bdg_ctl(struct nmreq *nmr, bdg_lookup_fn_t func);
u_int netmap_bdg_learning(char *, u_int, uint8_t *, struct netmap_adapter *);
#define NM_NAME "vale" /* prefix for the bridge port name */
#define NM_BDG_MAXPORTS 254 /* up to 32 for bitmap, 254 ok otherwise */
#define NM_BDG_BROADCAST NM_BDG_MAXPORTS
#define NM_BDG_NOPORT (NM_BDG_MAXPORTS+1)
extern u_int netmap_buf_size;
#define NETMAP_BUF_SIZE netmap_buf_size // XXX remove
extern int netmap_mitigate;
extern int netmap_no_pendintr;
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,
};
/*
* NA returns a pointer to the struct netmap adapter from the ifp,
* WNA is used to write it.
* SWNA() is used for the "host stack" endpoint associated
* to an interface. It is allocated together with the main NA(),
* as an array of two objects.
*/
#ifndef WNA
#define WNA(_ifp) (_ifp)->if_pspare[0]
#endif
#define NA(_ifp) ((struct netmap_adapter *)WNA(_ifp))
#define SWNA(_ifp) (NA(_ifp) + 1)
/*
* Macros to determine if an interface is netmap capable or netmap enabled.
* See the magic field in struct netmap_adapter.
*/
#ifdef __FreeBSD__
/*
* on FreeBSD just use if_capabilities and if_capenable.
*/
#define NETMAP_CAPABLE(ifp) (NA(ifp) && \
(ifp)->if_capabilities & IFCAP_NETMAP )
#define NETMAP_SET_CAPABLE(ifp) \
(ifp)->if_capabilities |= IFCAP_NETMAP
#else /* linux */
/*
* on linux:
* we check if NA(ifp) is set and its first element has a related
* magic value. The capenable is within the struct netmap_adapter.
*/
#define NETMAP_MAGIC 0x52697a7a
#define NETMAP_CAPABLE(ifp) (NA(ifp) && \
((uint32_t)(uintptr_t)NA(ifp) ^ NA(ifp)->magic) == NETMAP_MAGIC )
#define NETMAP_SET_CAPABLE(ifp) \
NA(ifp)->magic = ((uint32_t)(uintptr_t)NA(ifp)) ^ NETMAP_MAGIC
#endif /* linux */
#ifdef __FreeBSD__
/* Callback invoked by the dma machinery after a successfull dmamap_load */
static void netmap_dmamap_cb(__unused void *arg,
__unused bus_dma_segment_t * segs, __unused int nseg, __unused int error)
{
}
/* bus_dmamap_load wrapper: call aforementioned function if map != NULL.
* XXX can we do it without a callback ?
*/
static inline void
netmap_load_map(bus_dma_tag_t tag, bus_dmamap_t map, void *buf)
{
if (map)
bus_dmamap_load(tag, map, buf, NETMAP_BUF_SIZE,
netmap_dmamap_cb, NULL, BUS_DMA_NOWAIT);
}
/* update the map when a buffer changes. */
static inline void
netmap_reload_map(bus_dma_tag_t tag, bus_dmamap_t map, void *buf)
{
if (map) {
bus_dmamap_unload(tag, map);
bus_dmamap_load(tag, map, buf, NETMAP_BUF_SIZE,
netmap_dmamap_cb, NULL, BUS_DMA_NOWAIT);
}
}
#else /* linux */
/*
* XXX How do we redefine these functions:
*
* on linux we need
* dma_map_single(&pdev->dev, virt_addr, len, direction)
* dma_unmap_single(&adapter->pdev->dev, phys_addr, len, direction
* The len can be implicit (on netmap it is NETMAP_BUF_SIZE)
* unfortunately the direction is not, so we need to change
* something to have a cross API
*/
#define netmap_load_map(_t, _m, _b)
#define netmap_reload_map(_t, _m, _b)
#if 0
struct e1000_buffer *buffer_info = &tx_ring->buffer_info[l];
/* set time_stamp *before* dma to help avoid a possible race */
buffer_info->time_stamp = jiffies;
buffer_info->mapped_as_page = false;
buffer_info->length = len;
//buffer_info->next_to_watch = l;
/* reload dma map */
dma_unmap_single(&adapter->pdev->dev, buffer_info->dma,
NETMAP_BUF_SIZE, DMA_TO_DEVICE);
buffer_info->dma = dma_map_single(&adapter->pdev->dev,
addr, NETMAP_BUF_SIZE, DMA_TO_DEVICE);
if (dma_mapping_error(&adapter->pdev->dev, buffer_info->dma)) {
D("dma mapping error");
/* goto dma_error; See e1000_put_txbuf() */
/* XXX reset */
}
tx_desc->buffer_addr = htole64(buffer_info->dma); //XXX
#endif
/*
* The bus_dmamap_sync() can be one of wmb() or rmb() depending on direction.
*/
#define bus_dmamap_sync(_a, _b, _c)
#endif /* linux */
/*
* functions to map NIC to KRING indexes (n2k) and vice versa (k2n)
*/
static inline int
netmap_idx_n2k(struct netmap_kring *kr, int idx)
{
int n = kr->nkr_num_slots;
idx += kr->nkr_hwofs;
if (idx < 0)
return idx + n;
else if (idx < n)
return idx;
else
return idx - n;
}
static inline int
netmap_idx_k2n(struct netmap_kring *kr, int idx)
{
int n = kr->nkr_num_slots;
idx -= kr->nkr_hwofs;
if (idx < 0)
return idx + n;
else if (idx < n)
return idx;
else
return idx - n;
}
/* Entries of the look-up table. */
struct lut_entry {
void *vaddr; /* virtual address. */
vm_paddr_t paddr; /* physical address. */
};
struct netmap_obj_pool;
extern struct lut_entry *netmap_buffer_lut;
#define NMB_VA(i) (netmap_buffer_lut[i].vaddr)
#define NMB_PA(i) (netmap_buffer_lut[i].paddr)
/*
* NMB return the virtual address of a buffer (buffer 0 on bad index)
* PNMB also fills the physical address
*/
static inline void *
NMB(struct netmap_slot *slot)
{
uint32_t i = slot->buf_idx;
return (unlikely(i >= netmap_total_buffers)) ? NMB_VA(0) : NMB_VA(i);
}
static inline void *
PNMB(struct netmap_slot *slot, uint64_t *pp)
{
uint32_t i = slot->buf_idx;
void *ret = (i >= netmap_total_buffers) ? NMB_VA(0) : NMB_VA(i);
*pp = (i >= netmap_total_buffers) ? NMB_PA(0) : NMB_PA(i);
return ret;
}
/* default functions to handle rx/tx interrupts */
int netmap_rx_irq(struct ifnet *, u_int, u_int *);
#define netmap_tx_irq(_n, _q) netmap_rx_irq(_n, _q, NULL)
#ifdef __FreeBSD__
MALLOC_DECLARE(M_NETMAP);
#endif /* __FreeBSD__ */
void netmap_disable_all_rings(struct ifnet *);
void netmap_enable_all_rings(struct ifnet *);
#endif /* _NET_NETMAP_KERN_H_ */