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 static struct objcache *sf_buf_cache; 47 48 MALLOC_DEFINE(M_SFBUF, "sfbuf", "Sendfile buffer structures"); 49 struct objcache_malloc_args sf_buf_malloc_args = { sizeof(struct sf_buf), M_SFBUF }; 50 51 52 static boolean_t 53 sf_buf_cache_ctor(void *obj, void *pdata, int ocflags) 54 { 55 struct sf_buf *sf = (struct sf_buf *)obj; 56 57 sf->lwbuf = NULL; 58 refcount_init(&sf->ref, 0); 59 60 return (TRUE); 61 } 62 63 /* 64 * Init objcache of sf_bufs (sendfile(2) or "super-fast" if you prefer. :-)) 65 */ 66 static void 67 sf_buf_init(void *arg) 68 { 69 sf_buf_cache = objcache_create("sf_buf", 0, 0, 70 sf_buf_cache_ctor, NULL, NULL, 71 objcache_malloc_alloc, objcache_malloc_free, 72 &sf_buf_malloc_args); 73 } 74 75 /* 76 * Acquire an sf_buf reference for a vm_page. 77 */ 78 struct sf_buf * 79 sf_buf_alloc(struct vm_page *m) 80 { 81 struct sf_buf *sf; 82 83 if ((sf = objcache_get(sf_buf_cache, M_WAITOK)) == NULL) 84 goto done; 85 86 if ((sf->lwbuf = lwbuf_alloc(m, &sf->lwbuf_cache)) == NULL) { 87 objcache_put(sf_buf_cache, sf); 88 sf = NULL; 89 goto done; 90 } 91 92 /* 93 * Force invalidation of the TLB entry on all CPU's 94 */ 95 lwbuf_set_global(sf->lwbuf); 96 97 refcount_init(&sf->ref, 1); 98 99 done: 100 return (sf); 101 } 102 103 void 104 sf_buf_ref(void *arg) 105 { 106 struct sf_buf *sf = arg; 107 108 refcount_acquire(&sf->ref); 109 } 110 111 /* 112 * Detach mapped page and release resources back to the system. 113 * 114 * Returns non-zero (TRUE) if this was the last release of the sfbuf. 115 * 116 * (matching the same API that refcount_release() uses to reduce confusion) 117 */ 118 int 119 sf_buf_free(void *arg) 120 { 121 struct sf_buf *sf = arg; 122 123 if (refcount_release(&sf->ref)) { 124 lwbuf_free(sf->lwbuf); 125 objcache_put(sf_buf_cache, sf); 126 return (1); 127 } 128 return (0); 129 } 130