/* * 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: head/sys/dev/netmap/netmap_mem2.c 234290 2012-04-14 16:44:18Z luigi $ * * (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; }; #define NMA_LOCK_T struct lock 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