1 /*- 2 * Copyright (c) 2014 Gleb Smirnoff <glebius@FreeBSD.org> 3 * Copyright (c) 2003-2004 Alan L. Cox <alc@cs.rice.edu> 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 * 27 * $FreeBSD$ 28 */ 29 30 #ifndef _SYS_SF_BUF_H_ 31 #define _SYS_SF_BUF_H_ 32 33 struct sfstat { /* sendfile statistics */ 34 uint64_t sf_syscalls; /* times sendfile was called */ 35 uint64_t sf_noiocnt; /* times sendfile didn't require I/O */ 36 uint64_t sf_iocnt; /* times sendfile had to do disk I/O */ 37 uint64_t sf_pages_read; /* pages read as part of a request */ 38 uint64_t sf_pages_valid; /* pages were valid for a request */ 39 uint64_t sf_rhpages_requested; /* readahead pages requested */ 40 uint64_t sf_rhpages_read; /* readahead pages read */ 41 uint64_t sf_busy; /* times aborted on a busy page */ 42 uint64_t sf_allocfail; /* times sfbuf allocation failed */ 43 uint64_t sf_allocwait; /* times sfbuf allocation had to wait */ 44 uint64_t sf_pages_bogus; /* times bogus page was used */ 45 }; 46 47 #ifdef _KERNEL 48 #include <sys/types.h> 49 #include <sys/systm.h> 50 #include <sys/counter.h> 51 #include <vm/vm.h> 52 #include <vm/vm_param.h> 53 #include <vm/vm_page.h> 54 55 /* 56 * Sf_bufs, or sendfile(2) buffers provide a vm_page that is mapped 57 * into kernel address space. Note, that they aren't used only 58 * by sendfile(2)! 59 * 60 * Sf_bufs could be implemented as a feature of vm_page_t, but that 61 * would require growth of the structure. That's why they are implemented 62 * as a separate hash indexed by vm_page address. Implementation lives in 63 * kern/subr_sfbuf.c. Meanwhile, most 64-bit machines have a physical map, 64 * so they don't require this hash at all, thus ignore subr_sfbuf.c. 65 * 66 * Different 32-bit architectures demand different requirements on sf_buf 67 * hash and functions. They request features in machine/vmparam.h, which 68 * enable parts of this file. They can also optionally provide helpers in 69 * machine/sf_buf.h 70 * 71 * Defines are: 72 * SFBUF This machine requires sf_buf hash. 73 * subr_sfbuf.c should be compiled. 74 * SFBUF_CPUSET This machine can perform SFB_CPUPRIVATE mappings, 75 * that do no invalidate cache on the rest of CPUs. 76 * SFBUF_NOMD This machine doesn't have machine/sf_buf.h 77 * 78 * SFBUF_OPTIONAL_DIRECT_MAP Value of this define is used as boolean 79 * variable that tells whether machine is 80 * capable of direct map or not at runtime. 81 * SFBUF_MAP This machine provides its own sf_buf_map() and 82 * sf_buf_unmap(). 83 * SFBUF_PROCESS_PAGE This machine provides sf_buf_process_page() 84 * function. 85 */ 86 87 #ifdef SFBUF 88 #if defined(SMP) && defined(SFBUF_CPUSET) 89 #include <sys/_cpuset.h> 90 #endif 91 #include <sys/queue.h> 92 93 struct sf_buf { 94 LIST_ENTRY(sf_buf) list_entry; /* list of buffers */ 95 TAILQ_ENTRY(sf_buf) free_entry; /* list of buffers */ 96 vm_page_t m; /* currently mapped page */ 97 vm_offset_t kva; /* va of mapping */ 98 int ref_count; /* usage of this mapping */ 99 #if defined(SMP) && defined(SFBUF_CPUSET) 100 cpuset_t cpumask; /* where mapping is valid */ 101 #endif 102 }; 103 #else /* ! SFBUF */ 104 struct sf_buf; 105 #endif /* SFBUF */ 106 107 #ifndef SFBUF_NOMD 108 #include <machine/sf_buf.h> 109 #endif 110 #ifdef SFBUF_OPTIONAL_DIRECT_MAP 111 #include <machine/md_var.h> 112 #endif 113 114 #ifdef SFBUF 115 struct sf_buf *sf_buf_alloc(struct vm_page *, int); 116 void sf_buf_free(struct sf_buf *); 117 void sf_buf_ref(struct sf_buf *); 118 119 static inline vm_offset_t 120 sf_buf_kva(struct sf_buf *sf) 121 { 122 #ifdef SFBUF_OPTIONAL_DIRECT_MAP 123 if (SFBUF_OPTIONAL_DIRECT_MAP) 124 return (SFBUF_PHYS_DMAP(VM_PAGE_TO_PHYS((vm_page_t)sf))); 125 #endif 126 127 return (sf->kva); 128 } 129 130 static inline vm_page_t 131 sf_buf_page(struct sf_buf *sf) 132 { 133 #ifdef SFBUF_OPTIONAL_DIRECT_MAP 134 if (SFBUF_OPTIONAL_DIRECT_MAP) 135 return ((vm_page_t)sf); 136 #endif 137 138 return (sf->m); 139 } 140 141 #ifndef SFBUF_MAP 142 #include <vm/pmap.h> 143 144 static inline void 145 sf_buf_map(struct sf_buf *sf, int flags) 146 { 147 148 pmap_qenter(sf->kva, &sf->m, 1); 149 } 150 151 static inline int 152 sf_buf_unmap(struct sf_buf *sf) 153 { 154 155 return (0); 156 } 157 #endif /* SFBUF_MAP */ 158 159 #if defined(SMP) && defined(SFBUF_CPUSET) 160 void sf_buf_shootdown(struct sf_buf *, int); 161 #endif 162 163 #ifdef SFBUF_PROCESS_PAGE 164 boolean_t sf_buf_process_page(vm_page_t, void (*)(struct sf_buf *)); 165 #endif 166 167 #else /* ! SFBUF */ 168 169 static inline struct sf_buf * 170 sf_buf_alloc(struct vm_page *m, int pri) 171 { 172 173 return ((struct sf_buf *)m); 174 } 175 176 static inline void 177 sf_buf_free(struct sf_buf *sf) 178 { 179 } 180 181 static inline void 182 sf_buf_ref(struct sf_buf *sf) 183 { 184 } 185 #endif /* SFBUF */ 186 187 /* 188 * Options to sf_buf_alloc() are specified through its flags argument. This 189 * argument's value should be the result of a bitwise or'ing of one or more 190 * of the following values. 191 */ 192 #define SFB_CATCH 1 /* Check signals if the allocation 193 sleeps. */ 194 #define SFB_CPUPRIVATE 2 /* Create a CPU private mapping. */ 195 #define SFB_DEFAULT 0 196 #define SFB_NOWAIT 4 /* Return NULL if all bufs are used. */ 197 198 extern counter_u64_t sfstat[sizeof(struct sfstat) / sizeof(uint64_t)]; 199 #define SFSTAT_ADD(name, val) \ 200 counter_u64_add(sfstat[offsetof(struct sfstat, name) / sizeof(uint64_t)],\ 201 (val)) 202 #define SFSTAT_INC(name) SFSTAT_ADD(name, 1) 203 #endif /* _KERNEL */ 204 #endif /* !_SYS_SF_BUF_H_ */ 205