freebsd-skq/sys/dev/netmap/netmap_mem2.h
Luigi Rizzo f9790aeb88 split netmap code according to functions:
- netmap.c		base code
- netmap_freebsd.c	FreeBSD-specific code
- netmap_generic.c	emulate netmap over standard drivers
- netmap_mbq.c		simple mbuf tailq
- netmap_mem2.c		memory management
- netmap_vale.c		VALE switch

simplify devce-specific code
2013-12-15 08:37:24 +00:00

220 lines
8.3 KiB
C

/*
* Copyright (C) 2012-2013 Matteo Landi, Luigi Rizzo, Giuseppe Lettieri. 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.
*/
/*
* $FreeBSD$
*
* (New) memory allocator for netmap
*/
/*
* This allocator creates three memory pools:
* nm_if_pool for the struct netmap_if
* nm_ring_pool for the struct netmap_ring
* nm_buf_pool for the packet buffers.
*
* that contain netmap objects. Each pool is made of a number of clusters,
* multiple of a page size, each containing an integer number of objects.
* The clusters are contiguous in user space but not in the kernel.
* Only nm_buf_pool needs to be dma-able,
* but for convenience use the same type of allocator for all.
*
* Once mapped, the three pools are exported to userspace
* as a contiguous block, starting from nm_if_pool. Each
* cluster (and pool) is an integral number of pages.
* [ . . . ][ . . . . . .][ . . . . . . . . . .]
* nm_if nm_ring nm_buf
*
* The userspace areas contain offsets of the objects in userspace.
* When (at init time) we write these offsets, we find out the index
* of the object, and from there locate the offset from the beginning
* of the region.
*
* The invididual allocators manage a pool of memory for objects of
* the same size.
* The pool is split into smaller clusters, whose size is a
* multiple of the page size. The cluster size is chosen
* to minimize the waste for a given max cluster size
* (we do it by brute force, as we have relatively few objects
* per cluster).
*
* Objects are aligned to the cache line (64 bytes) rounding up object
* sizes when needed. A bitmap contains the state of each object.
* Allocation scans the bitmap; this is done only on attach, so we are not
* too worried about performance
*
* For each allocator we can define (thorugh sysctl) the size and
* number of each object. Memory is allocated at the first use of a
* netmap file descriptor, and can be freed when all such descriptors
* have been released (including unmapping the memory).
* If memory is scarce, the system tries to get as much as possible
* and the sysctl values reflect the actual allocation.
* Together with desired values, the sysctl export also absolute
* min and maximum values that cannot be overridden.
*
* struct netmap_if:
* variable size, max 16 bytes per ring pair plus some fixed amount.
* 1024 bytes should be large enough in practice.
*
* In the worst case we have one netmap_if per ring in the system.
*
* struct netmap_ring
* variable size, 8 byte per slot plus some fixed amount.
* Rings can be large (e.g. 4k slots, or >32Kbytes).
* We default to 36 KB (9 pages), and a few hundred rings.
*
* struct netmap_buffer
* The more the better, both because fast interfaces tend to have
* many slots, and because we may want to use buffers to store
* packets in userspace avoiding copies.
* Must contain a full frame (eg 1518, or more for vlans, jumbo
* frames etc.) plus be nicely aligned, plus some NICs restrict
* the size to multiple of 1K or so. Default to 2K
*/
#ifndef _NET_NETMAP_MEM2_H_
#define _NET_NETMAP_MEM2_H_
#define NETMAP_BUF_MAX_NUM 20*4096*2 /* large machine */
#define NETMAP_POOL_MAX_NAMSZ 32
enum {
NETMAP_IF_POOL = 0,
NETMAP_RING_POOL,
NETMAP_BUF_POOL,
NETMAP_POOLS_NR
};
struct netmap_obj_params {
u_int size;
u_int num;
};
struct netmap_obj_pool {
char name[NETMAP_POOL_MAX_NAMSZ]; /* name of the allocator */
/* ---------------------------------------------------*/
/* these are only meaningful if the pool is finalized */
/* (see 'finalized' field in netmap_mem_d) */
u_int objtotal; /* actual total number of objects. */
u_int memtotal; /* actual total memory space */
u_int numclusters; /* actual number of clusters */
u_int objfree; /* number of free objects. */
struct lut_entry *lut; /* virt,phys addresses, objtotal entries */
uint32_t *bitmap; /* one bit per buffer, 1 means free */
uint32_t bitmap_slots; /* number of uint32 entries in bitmap */
/* ---------------------------------------------------*/
/* limits */
u_int objminsize; /* minimum object size */
u_int objmaxsize; /* maximum object size */
u_int nummin; /* minimum number of objects */
u_int nummax; /* maximum number of objects */
/* these are changed only by config */
u_int _objtotal; /* total number of objects */
u_int _objsize; /* object size */
u_int _clustsize; /* cluster size */
u_int _clustentries; /* objects per cluster */
u_int _numclusters; /* number of clusters */
/* requested values */
u_int r_objtotal;
u_int r_objsize;
};
#ifdef linux
// XXX a mtx would suffice here 20130415 lr
#define NMA_LOCK_T struct semaphore
#else /* !linux */
#define NMA_LOCK_T struct mtx
#endif /* linux */
typedef int (*netmap_mem_config_t)(struct netmap_mem_d*);
typedef int (*netmap_mem_finalize_t)(struct netmap_mem_d*);
typedef void (*netmap_mem_deref_t)(struct netmap_mem_d*);
/* We implement two kinds of netmap_mem_d structures:
*
* - global: used by hardware NICS;
*
* - private: used by VALE ports.
*
* In both cases, the netmap_mem_d structure has the same lifetime as the
* netmap_adapter of the corresponding NIC or port. It is the responsibility of
* the client code to delete the private allocator when the associated
* netmap_adapter is freed (this is implemented by the NAF_MEM_OWNER flag in
* netmap.c). The 'refcount' field counts the number of active users of the
* structure. The global allocator uses this information to prevent/allow
* reconfiguration. The private allocators release all their memory when there
* are no active users. By 'active user' we mean an existing netmap_priv
* structure holding a reference to the allocator.
*/
struct netmap_mem_d {
NMA_LOCK_T nm_mtx; /* protect the allocator */
u_int nm_totalsize; /* shorthand */
u_int flags;
#define NETMAP_MEM_FINALIZED 0x1 /* preallocation done */
#define NETMAP_MEM_PRIVATE 0x2 /* uses private address space */
int lasterr; /* last error for curr config */
int refcount; /* existing priv structures */
/* the three allocators */
struct netmap_obj_pool pools[NETMAP_POOLS_NR];
netmap_mem_config_t config;
netmap_mem_finalize_t finalize;
netmap_mem_deref_t deref;
};
extern struct netmap_mem_d nm_mem;
vm_paddr_t netmap_mem_ofstophys(struct netmap_mem_d *, vm_ooffset_t);
int netmap_mem_finalize(struct netmap_mem_d *);
int netmap_mem_init(void);
void netmap_mem_fini(void);
struct netmap_if *
netmap_mem_if_new(const char *, struct netmap_adapter *);
void netmap_mem_if_delete(struct netmap_adapter *, struct netmap_if *);
int netmap_mem_rings_create(struct netmap_adapter *);
void netmap_mem_rings_delete(struct netmap_adapter *);
void netmap_mem_deref(struct netmap_mem_d *);
int netmap_mem_get_info(struct netmap_mem_d *, u_int *size, u_int *memflags);
ssize_t netmap_mem_if_offset(struct netmap_mem_d *, const void *vaddr);
struct netmap_mem_d*
netmap_mem_private_new(const char *name, u_int txr, u_int txd, u_int rxr, u_int rxd);
void netmap_mem_private_delete(struct netmap_mem_d *);
#define NETMAP_BDG_BUF_SIZE(n) ((n)->pools[NETMAP_BUF_POOL]._objsize)
#endif