1 /*- 2 * Copyright (c) 2014 Gleb Smirnoff <[email protected]> 3 * Copyright (c) 2003-2004 Alan L. Cox <[email protected]> 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 }; 45 46 #ifdef _KERNEL 47 #include <sys/types.h> 48 #include <sys/systm.h> 49 #include <sys/counter.h> 50 #include <vm/vm.h> 51 #include <vm/vm_param.h> 52 #include <vm/vm_page.h> 53 54 /* 55 * Sf_bufs, or sendfile(2) buffers provide a vm_page that is mapped 56 * into kernel address space. Note, that they aren't used only 57 * by sendfile(2)! 58 * 59 * Sf_bufs could be implemented as a feature of vm_page_t, but that 60 * would require growth of the structure. That's why they are implemented 61 * as a separate hash indexed by vm_page address. Implementation lives in 62 * kern/subr_sfbuf.c. Meanwhile, most 64-bit machines have a physical map, 63 * so they don't require this hash at all, thus ignore subr_sfbuf.c. 64 * 65 * Different 32-bit architectures demand different requirements on sf_buf 66 * hash and functions. They request features in machine/vmparam.h, which 67 * enable parts of this file. They can also optionally provide helpers in 68 * machine/sf_buf.h 69 * 70 * Defines are: 71 * SFBUF This machine requires sf_buf hash. 72 * subr_sfbuf.c should be compiled. 73 * SFBUF_CPUSET This machine can perform SFB_CPUPRIVATE mappings, 74 * that do no invalidate cache on the rest of CPUs. 75 * SFBUF_NOMD This machine doesn't have machine/sf_buf.h 76 * 77 * SFBUF_OPTIONAL_DIRECT_MAP Value of this define is used as boolean 78 * variable that tells whether machine is 79 * capable of direct map or not at runtime. 80 * SFBUF_MAP This machine provides its own sf_buf_map() and 81 * sf_buf_unmap(). 82 * SFBUF_PROCESS_PAGE This machine provides sf_buf_process_page() 83 * function. 84 */ 85 86 #ifdef SFBUF 87 #if defined(SMP) && defined(SFBUF_CPUSET) 88 #include <sys/_cpuset.h> 89 #endif 90 #include <sys/queue.h> 91 92 struct sf_buf { 93 LIST_ENTRY(sf_buf) list_entry; /* list of buffers */ 94 TAILQ_ENTRY(sf_buf) free_entry; /* list of buffers */ 95 vm_page_t m; /* currently mapped page */ 96 vm_offset_t kva; /* va of mapping */ 97 int ref_count; /* usage of this mapping */ 98 #if defined(SMP) && defined(SFBUF_CPUSET) 99 cpuset_t cpumask; /* where mapping is valid */ 100 #endif 101 }; 102 #else /* ! SFBUF */ 103 struct sf_buf; 104 #endif /* SFBUF */ 105 106 #ifndef SFBUF_NOMD 107 #include <machine/sf_buf.h> 108 #endif 109 #ifdef SFBUF_OPTIONAL_DIRECT_MAP 110 #include <machine/md_var.h> 111 #endif 112 113 #ifdef SFBUF 114 struct sf_buf *sf_buf_alloc(struct vm_page *, int); 115 void sf_buf_free(struct sf_buf *); 116 void sf_buf_ref(struct sf_buf *); 117 118 static inline vm_offset_t 119 sf_buf_kva(struct sf_buf *sf) 120 { 121 #ifdef SFBUF_OPTIONAL_DIRECT_MAP 122 if (SFBUF_OPTIONAL_DIRECT_MAP) 123 return (SFBUF_PHYS_DMAP(VM_PAGE_TO_PHYS((vm_page_t)sf))); 124 #endif 125 126 return (sf->kva); 127 } 128 129 static inline vm_page_t 130 sf_buf_page(struct sf_buf *sf) 131 { 132 #ifdef SFBUF_OPTIONAL_DIRECT_MAP 133 if (SFBUF_OPTIONAL_DIRECT_MAP) 134 return ((vm_page_t)sf); 135 #endif 136 137 return (sf->m); 138 } 139 140 #ifndef SFBUF_MAP 141 #include <vm/pmap.h> 142 143 static inline void 144 sf_buf_map(struct sf_buf *sf, int flags) 145 { 146 147 pmap_qenter(sf->kva, &sf->m, 1); 148 } 149 150 static inline int 151 sf_buf_unmap(struct sf_buf *sf) 152 { 153 154 return (0); 155 } 156 #endif /* SFBUF_MAP */ 157 158 #if defined(SMP) && defined(SFBUF_CPUSET) 159 void sf_buf_shootdown(struct sf_buf *, int); 160 #endif 161 162 #ifdef SFBUF_PROCESS_PAGE 163 boolean_t sf_buf_process_page(vm_page_t, void (*)(struct sf_buf *)); 164 #endif 165 166 #else /* ! SFBUF */ 167 168 static inline struct sf_buf * 169 sf_buf_alloc(struct vm_page *m, int pri) 170 { 171 172 return ((struct sf_buf *)m); 173 } 174 175 static inline void 176 sf_buf_free(struct sf_buf *sf) 177 { 178 } 179 180 static inline void 181 sf_buf_ref(struct sf_buf *sf) 182 { 183 } 184 #endif /* SFBUF */ 185 186 /* 187 * Options to sf_buf_alloc() are specified through its flags argument. This 188 * argument's value should be the result of a bitwise or'ing of one or more 189 * of the following values. 190 */ 191 #define SFB_CATCH 1 /* Check signals if the allocation 192 sleeps. */ 193 #define SFB_CPUPRIVATE 2 /* Create a CPU private mapping. */ 194 #define SFB_DEFAULT 0 195 #define SFB_NOWAIT 4 /* Return NULL if all bufs are used. */ 196 197 extern counter_u64_t sfstat[sizeof(struct sfstat) / sizeof(uint64_t)]; 198 #define SFSTAT_ADD(name, val) \ 199 counter_u64_add(sfstat[offsetof(struct sfstat, name) / sizeof(uint64_t)],\ 200 (val)) 201 #define SFSTAT_INC(name) SFSTAT_ADD(name, 1) 202 #endif /* _KERNEL */ 203 #endif /* !_SYS_SF_BUF_H_ */ 204