diff options
| author | Luigi Rizzo <luigi@FreeBSD.org> | 2014-02-15 04:53:04 +0000 |
|---|---|---|
| committer | Luigi Rizzo <luigi@FreeBSD.org> | 2014-02-15 04:53:04 +0000 |
| commit | f0ea3689a9c1c27067145ed902811149e78cc4fa (patch) | |
| tree | 5f40d56905d46741e85cd83a0278b12363e3e2a7 /sys/net/netmap.h | |
| parent | 53bf5ef829d5fd312db3851ce6cb589173b744e1 (diff) | |
Notes
Diffstat (limited to 'sys/net/netmap.h')
| -rw-r--r-- | sys/net/netmap.h | 163 |
1 files changed, 139 insertions, 24 deletions
diff --git a/sys/net/netmap.h b/sys/net/netmap.h index a5ee9b55edc9..f0b4c56d4e39 100644 --- a/sys/net/netmap.h +++ b/sys/net/netmap.h @@ -39,8 +39,10 @@ #ifndef _NET_NETMAP_H_ #define _NET_NETMAP_H_ -#define NETMAP_API 10 /* current API version */ +#define NETMAP_API 11 /* current API version */ +#define NETMAP_MIN_API 11 /* min and max versions accepted */ +#define NETMAP_MAX_API 15 /* * Some fields should be cache-aligned to reduce contention. * The alignment is architecture and OS dependent, but rather than @@ -73,20 +75,21 @@ +===============+ / | buf_idx, len | slot[1] | txring_ofs[0] | (rel.to nifp)--' | flags, ptr | | txring_ofs[1] | +---------------+ - (tx+1+extra_tx entries) (num_slots entries) + (tx+1 entries) (num_slots entries) | txring_ofs[t] | | buf_idx, len | slot[n-1] +---------------+ | flags, ptr | | rxring_ofs[0] | +---------------+ | rxring_ofs[1] | - (rx+1+extra_rx entries) + (rx+1 entries) | rxring_ofs[r] | +---------------+ - * For each "interface" (NIC, host stack, VALE switch port) attached to a - * file descriptor, the mmap()ed region contains a (logically readonly) + * For each "interface" (NIC, host stack, PIPE, VALE switch port) bound to + * a file descriptor, the mmap()ed region contains a (logically readonly) * struct netmap_if pointing to struct netmap_ring's. + * * There is one netmap_ring per physical NIC ring, plus one tx/rx ring - * pair attached to the host stack (this pair is unused for VALE ports). + * pair attached to the host stack (this pair is unused for non-NIC ports). * * All physical/host stack ports share the same memory region, * so that zero-copy can be implemented between them. @@ -98,7 +101,42 @@ * is provided for user-supplied buffers in the tx path. * * In user space, the buffer address is computed as - * (char *)ring + buf_ofs + index*NETMAP_BUF_SIZE + * (char *)ring + buf_ofs + index * NETMAP_BUF_SIZE + * + * Added in NETMAP_API 11: + * + * + NIOCREGIF can request the allocation of extra spare buffers from + * the same memory pool. The desired number of buffers must be in + * nr_arg3. The ioctl may return fewer buffers, depending on memory + * availability. nr_arg3 will return the actual value, and, once + * mapped, nifp->ni_bufs_head will be the index of the first buffer. + * + * The buffers are linked to each other using the first uint32_t + * as the index. On close, ni_bufs_head must point to the list of + * buffers to be released. + * + * + NIOCREGIF can request space for extra rings (and buffers) + * allocated in the same memory space. The number of extra rings + * is in nr_arg1, and is advisory. This is a no-op on NICs where + * the size of the memory space is fixed. + * + * + NIOCREGIF can attach to PIPE rings sharing the same memory + * space with a parent device. The ifname indicates the parent device, + * which must already exist. Flags in nr_flags indicate if we want to + * bind the master or slave side, the index (from nr_ringid) + * is just a cookie and does need to be sequential. + * + * + NIOCREGIF can also attach to 'monitor' rings that replicate + * the content of specific rings, also from the same memory space. + * + * Extra flags in nr_flags support the above functions. + * Application libraries may use the following naming scheme: + * netmap:foo all NIC ring pairs + * netmap:foo^ only host ring pair + * netmap:foo+ all NIC ring + host ring pairs + * netmap:foo-k the k-th NIC ring pair + * netmap:foo{k PIPE ring pair k, master side + * netmap:foo}k PIPE ring pair k, slave side */ /* @@ -284,8 +322,8 @@ struct netmap_if { const uint32_t ni_tx_rings; /* number of HW tx rings */ const uint32_t ni_rx_rings; /* number of HW rx rings */ - const uint32_t ni_extra_tx_rings; - const uint32_t ni_extra_rx_rings; + uint32_t ni_bufs_head; /* head index for extra bufs */ + uint32_t ni_spare1[5]; /* * The following array contains the offset of each netmap ring * from this structure, in the following order: @@ -321,6 +359,7 @@ struct netmap_if { * * The actual argument (struct nmreq) has a number of options to request * different functions. + * The following are used in NIOCREGIF when nr_cmd == 0: * * nr_name (in) * The name of the port (em0, valeXXX:YYY, etc.) @@ -337,6 +376,13 @@ struct netmap_if { * * nr_ringid (in) * Indicates how rings should be bound to the file descriptors. + * If nr_flags != 0, then the low bits (in NETMAP_RING_MASK) + * are used to indicate the ring number, and nr_flags specifies + * the actual rings to bind. NETMAP_NO_TX_POLL is unaffected. + * + * NOTE: THE FOLLOWING (nr_flags == 0) IS DEPRECATED: + * If nr_flags == 0, NETMAP_HW_RING and NETMAP_SW_RING control + * the binding as follows: * 0 (default) binds all physical rings * NETMAP_HW_RING | ring number binds a single ring pair * NETMAP_SW_RING binds only the host tx/rx rings @@ -345,8 +391,41 @@ struct netmap_if { * packets on tx rings only if POLLOUT is set. * The default is to push any pending packet. * - * NETMAP_PRIV_MEM is set on return for ports that use private - * memory regions and cannot use buffer swapping. + * NETMAP_DO_RX_POLL can be OR-ed to make select()/poll() release + * packets on rx rings also when POLLIN is NOT set. + * The default is to touch the rx ring only with POLLIN. + * Note that this is the opposite of TX because it + * reflects the common usage. + * + * NOTE: NETMAP_PRIV_MEM IS DEPRECATED, use nr_arg2 instead. + * NETMAP_PRIV_MEM is set on return for ports that do not use + * the global memory allocator. + * This information is not significant and applications + * should look at the region id in nr_arg2 + * + * nr_flags is the recommended mode to indicate which rings should + * be bound to a file descriptor. Values are NR_REG_* + * + * nr_arg1 (in) The number of extra rings to be reserved. + * Especially when allocating a VALE port the system only + * allocates the amount of memory needed for the port. + * If more shared memory rings are desired (e.g. for pipes), + * the first invocation for the same basename/allocator + * should specify a suitable number. Memory cannot be + * extended after the first allocation without closing + * all ports on the same region. + * + * nr_arg2 (in/out) The identity of the memory region used. + * On input, 0 means the system decides autonomously, + * other values may try to select a specific region. + * On return the actual value is reported. + * Region '1' is the global allocator, normally shared + * by all interfaces. Other values are private regions. + * If two ports the same region zero-copy is possible. + * + * nr_arg3 (in/out) number of extra buffers to be allocated. + * + * * * nr_cmd (in) if non-zero indicates a special command: * NETMAP_BDG_ATTACH and nr_name = vale*:ifname @@ -362,17 +441,33 @@ struct netmap_if { * NETMAP_BDG_LIST * list the configuration of VALE switches. * - * NETMAP_BDG_OFFSET XXX ? - * Set the offset of data in packets. Used with VALE - * switches where the clients use the vhost header. + * NETMAP_BDG_VNET_HDR + * Set the virtio-net header length used by the client + * of a VALE switch port. * - * nr_arg1, nr_arg2 (in/out) command specific + * nr_arg1, nr_arg2, nr_arg3 (in/out) command specific + * + * * */ /* - * struct nmreq overlays a struct ifreq + * struct nmreq overlays a struct ifreq (just the name) + * + * On input, nr_ringid indicates which rings we are requesting, + * with the low flags for the specific ring number. + * selection FLAGS RING INDEX + * + * all the NIC rings 0x0000 - + * only HOST ring 0x2000 ring index + * single NIC ring 0x4000 - + * all the NIC+HOST rings 0x6000 - + * one pipe ring, master 0x8000 ring index + * *** INVALID 0xA000 + * one pipe ring, slave 0xC000 ring index + * *** INVALID 0xE000 + * */ struct nmreq { char nr_name[IFNAMSIZ]; @@ -383,27 +478,47 @@ struct nmreq { uint32_t nr_rx_slots; /* slots in rx rings */ uint16_t nr_tx_rings; /* number of tx rings */ uint16_t nr_rx_rings; /* number of rx rings */ + uint16_t nr_ringid; /* ring(s) we care about */ -#define NETMAP_PRIV_MEM 0x8000 /* rings use private memory */ -#define NETMAP_HW_RING 0x4000 /* low bits indicate one hw ring */ -#define NETMAP_SW_RING 0x2000 /* process the sw ring */ +#define NETMAP_HW_RING 0x4000 /* single NIC ring pair */ +#define NETMAP_SW_RING 0x2000 /* only host ring pair */ + +#define NETMAP_RING_MASK 0x0fff /* the ring number */ + #define NETMAP_NO_TX_POLL 0x1000 /* no automatic txsync on poll */ -#define NETMAP_RING_MASK 0xfff /* the ring number */ + +#define NETMAP_DO_RX_POLL 0x8000 /* DO automatic rxsync on poll */ uint16_t nr_cmd; #define NETMAP_BDG_ATTACH 1 /* attach the NIC */ #define NETMAP_BDG_DETACH 2 /* detach the NIC */ #define NETMAP_BDG_LOOKUP_REG 3 /* register lookup function */ #define NETMAP_BDG_LIST 4 /* get bridge's info */ -#define NETMAP_BDG_OFFSET 5 /* set the port offset */ +#define NETMAP_BDG_VNET_HDR 5 /* set the port virtio-net-hdr length */ +#define NETMAP_BDG_OFFSET NETMAP_BDG_VNET_HDR /* deprecated alias */ - uint16_t nr_arg1; + uint16_t nr_arg1; /* reserve extra rings in NIOCREGIF */ #define NETMAP_BDG_HOST 1 /* attach the host stack on ATTACH */ -#define NETMAP_BDG_MAX_OFFSET 12 uint16_t nr_arg2; - uint32_t spare2[3]; + uint32_t nr_arg3; /* req. extra buffers in NIOCREGIF */ + uint32_t nr_flags; + /* various modes, extends nr_ringid */ + uint32_t spare2[1]; +}; + +#define NR_REG_MASK 0xf /* values for nr_flags */ +enum { NR_REG_DEFAULT = 0, /* backward compat, should not be used. */ + NR_REG_ALL_NIC = 1, + NR_REG_SW = 2, + NR_REG_NIC_SW = 3, + NR_REG_ONE_NIC = 4, + NR_REG_PIPE_MASTER = 5, + NR_REG_PIPE_SLAVE = 6, }; +/* monitor uses the NR_REG to select the rings to monitor */ +#define NR_MONITOR_TX 0x100 +#define NR_MONITOR_RX 0x200 /* |
