1 /* 2 * Copyright (c) 1998 David Greenman. All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 1. Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * 2. Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * 13 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 14 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 16 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 17 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 18 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 19 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 20 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 21 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 22 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 23 * SUCH DAMAGE. 24 */ 25 26 #include <sys/param.h> 27 #include <sys/types.h> 28 #include <sys/systm.h> 29 #include <sys/kernel.h> 30 #include <sys/malloc.h> 31 #include <sys/sfbuf.h> 32 #include <sys/refcount.h> 33 #include <sys/objcache.h> 34 35 #include <cpu/lwbuf.h> 36 37 #include <vm/vm.h> 38 #include <vm/vm_extern.h> 39 #include <vm/vm_kern.h> 40 #include <vm/vm_page.h> 41 #include <vm/pmap.h> 42 43 static void sf_buf_init(void *arg); 44 SYSINIT(sock_sf, SI_BOOT2_MACHDEP, SI_ORDER_ANY, sf_buf_init, NULL); 45 46 LIST_HEAD(sf_buf_list, sf_buf); 47 48 static struct objcache *sf_buf_cache; 49 50 MALLOC_DEFINE(M_SFBUF, "sfbuf", "Sendfile buffer structures"); 51 struct objcache_malloc_args sf_buf_malloc_args = { sizeof(struct sf_buf), M_SFBUF }; 52 53 54 static boolean_t 55 sf_buf_cache_ctor(void *obj, void *pdata, int ocflags) 56 { 57 struct sf_buf *sf = (struct sf_buf *)obj; 58 59 sf->lwbuf = NULL; 60 refcount_init(&sf->ref, 0); 61 62 return (TRUE); 63 } 64 65 /* 66 * Init objcache of sf_bufs (sendfile(2) or "super-fast" if you prefer. :-)) 67 */ 68 static void 69 sf_buf_init(void *arg) 70 { 71 sf_buf_cache = objcache_create("sf_buf", 0, 0, 72 sf_buf_cache_ctor, NULL, NULL, 73 objcache_malloc_alloc, objcache_malloc_free, 74 &sf_buf_malloc_args); 75 } 76 77 /* 78 * Acquire an sf_buf reference for a vm_page. 79 */ 80 struct sf_buf * 81 sf_buf_alloc(struct vm_page *m) 82 { 83 struct sf_buf *sf; 84 85 if ((sf = objcache_get(sf_buf_cache, M_WAITOK)) == NULL) 86 goto done; 87 88 if ((sf->lwbuf = lwbuf_alloc(m, &sf->lwbuf_cache)) == NULL) { 89 objcache_put(sf_buf_cache, sf); 90 sf = NULL; 91 goto done; 92 } 93 94 /* 95 * Force invalidation of the TLB entry on all CPU's 96 */ 97 lwbuf_set_global(sf->lwbuf); 98 99 refcount_init(&sf->ref, 1); 100 101 done: 102 return (sf); 103 } 104 105 void 106 sf_buf_ref(void *arg) 107 { 108 struct sf_buf *sf = arg; 109 110 refcount_acquire(&sf->ref); 111 } 112 113 /* 114 * Detach mapped page and release resources back to the system. 115 * 116 * Returns non-zero (TRUE) if this was the last release of the sfbuf. 117 * 118 * (matching the same API that refcount_release() uses to reduce confusion) 119 */ 120 int 121 sf_buf_free(void *arg) 122 { 123 struct sf_buf *sf = arg; 124 125 if (refcount_release(&sf->ref)) { 126 lwbuf_free(sf->lwbuf); 127 objcache_put(sf_buf_cache, sf); 128 return (1); 129 } 130 return (0); 131 } 132