1/*- 2 * Copyright (c) 1980, 1986, 1989, 1993 3 * The Regents of the University of California. All rights reserved. 4 * (c) UNIX System Laboratories, Inc. 5 * All or some portions of this file are derived from material licensed 6 * to the University of California by American Telephone and Telegraph 7 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 8 * the permission of UNIX System Laboratories, Inc. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 4. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 * @(#)param.c 8.3 (Berkeley) 8/20/94 35 */ 36 37#include <sys/cdefs.h> 38__FBSDID("$FreeBSD$"); 39 40#include "opt_param.h" 41#include "opt_msgbuf.h" 42#include "opt_maxusers.h" 43 44#include <sys/param.h> 45#include <sys/systm.h> 46#include <sys/kernel.h> 47#include <sys/limits.h> 48#include <sys/msgbuf.h> 49#include <sys/sysctl.h> 50#include <sys/proc.h> 51 52#include <vm/vm.h> 53#include <vm/vm_param.h> 54#include <vm/pmap.h> 55 56/* 57 * System parameter formulae. 58 */ 59 60#ifndef HZ 61# if defined(__mips__) || defined(__arm__) 62# define HZ 100 63# else 64# define HZ 1000 65# endif 66# ifndef HZ_VM 67# define HZ_VM 100 68# endif 69#else 70# ifndef HZ_VM 71# define HZ_VM HZ 72# endif 73#endif 74#define NPROC (20 + 16 * maxusers) 75#ifndef NBUF 76#define NBUF 0 77#endif 78#ifndef MAXFILES 79#define MAXFILES (maxproc * 2) 80#endif 81 82static int sysctl_kern_vm_guest(SYSCTL_HANDLER_ARGS); 83 84int hz; 85int tick; 86int maxusers; /* base tunable */ 87int maxproc; /* maximum # of processes */ 88int maxprocperuid; /* max # of procs per user */ 89int maxfiles; /* sys. wide open files limit */ 90int maxfilesperproc; /* per-proc open files limit */ 91int msgbufsize; /* size of kernel message buffer */ 92int ncallout; /* maximum # of timer events */ 93int nbuf; 94int bio_transient_maxcnt; 95int ngroups_max; /* max # groups per process */ 96int nswbuf; 97pid_t pid_max = PID_MAX; 98long maxswzone; /* max swmeta KVA storage */ 99long maxbcache; /* max buffer cache KVA storage */ 100long maxpipekva; /* Limit on pipe KVA */ 101int vm_guest; /* Running as virtual machine guest? */ 102u_long maxtsiz; /* max text size */ 103u_long dfldsiz; /* initial data size limit */ 104u_long maxdsiz; /* max data size */ 105u_long dflssiz; /* initial stack size limit */ 106u_long maxssiz; /* max stack size */ 107u_long sgrowsiz; /* amount to grow stack */ 108 109SYSCTL_INT(_kern, OID_AUTO, hz, CTLFLAG_RDTUN, &hz, 0, 110 "Number of clock ticks per second"); 111SYSCTL_INT(_kern, OID_AUTO, ncallout, CTLFLAG_RDTUN, &ncallout, 0, 112 "Number of pre-allocated timer events"); 113SYSCTL_INT(_kern, OID_AUTO, nbuf, CTLFLAG_RDTUN, &nbuf, 0, 114 "Number of buffers in the buffer cache"); 115SYSCTL_INT(_kern, OID_AUTO, nswbuf, CTLFLAG_RDTUN, &nswbuf, 0, 116 "Number of swap buffers"); 117SYSCTL_INT(_kern, OID_AUTO, msgbufsize, CTLFLAG_RDTUN, &msgbufsize, 0, 118 "Size of the kernel message buffer"); 119SYSCTL_LONG(_kern, OID_AUTO, maxswzone, CTLFLAG_RDTUN, &maxswzone, 0, 120 "Maximum memory for swap metadata"); 121SYSCTL_LONG(_kern, OID_AUTO, maxbcache, CTLFLAG_RDTUN, &maxbcache, 0, 122 "Maximum value of vfs.maxbufspace"); 123SYSCTL_INT(_kern, OID_AUTO, bio_transient_maxcnt, CTLFLAG_RDTUN, 124 &bio_transient_maxcnt, 0, 125 "Maximum number of transient BIOs mappings"); 126SYSCTL_ULONG(_kern, OID_AUTO, maxtsiz, CTLFLAG_RW | CTLFLAG_TUN, &maxtsiz, 0, 127 "Maximum text size"); 128SYSCTL_ULONG(_kern, OID_AUTO, dfldsiz, CTLFLAG_RW | CTLFLAG_TUN, &dfldsiz, 0, 129 "Initial data size limit"); 130SYSCTL_ULONG(_kern, OID_AUTO, maxdsiz, CTLFLAG_RW | CTLFLAG_TUN, &maxdsiz, 0, 131 "Maximum data size"); 132SYSCTL_ULONG(_kern, OID_AUTO, dflssiz, CTLFLAG_RW | CTLFLAG_TUN, &dflssiz, 0, 133 "Initial stack size limit"); 134SYSCTL_ULONG(_kern, OID_AUTO, maxssiz, CTLFLAG_RW | CTLFLAG_TUN, &maxssiz, 0, 135 "Maximum stack size"); 136SYSCTL_ULONG(_kern, OID_AUTO, sgrowsiz, CTLFLAG_RW | CTLFLAG_TUN, &sgrowsiz, 0, 137 "Amount to grow stack on a stack fault"); 138SYSCTL_PROC(_kern, OID_AUTO, vm_guest, CTLFLAG_RD | CTLTYPE_STRING, 139 NULL, 0, sysctl_kern_vm_guest, "A", 140 "Virtual machine guest detected? (none|generic|xen)"); 141 142/* 143 * These have to be allocated somewhere; allocating 144 * them here forces loader errors if this file is omitted 145 * (if they've been externed everywhere else; hah!). 146 */ 147struct buf *swbuf; 148 149/* 150 * The elements of this array are ordered based upon the values of the 151 * corresponding enum VM_GUEST members. 152 */ 153static const char *const vm_guest_sysctl_names[] = { 154 "none", 155 "generic", 156 "xen", 157 NULL 158}; 159 160#ifndef XEN 161static const char *const vm_bnames[] = { 162 "QEMU", /* QEMU */ 163 "Plex86", /* Plex86 */ 164 "Bochs", /* Bochs */ 165 "Xen", /* Xen */ 166 "BHYVE", /* bhyve */ 167 "Seabios", /* KVM */ 168 NULL 169}; 170 171static const char *const vm_pnames[] = { 172 "VMware Virtual Platform", /* VMWare VM */ 173 "Virtual Machine", /* Microsoft VirtualPC */ 174 "VirtualBox", /* Sun xVM VirtualBox */ 175 "Parallels Virtual Platform", /* Parallels VM */ 176 "KVM", /* KVM */ 177 NULL 178}; 179 180 181/* 182 * Detect known Virtual Machine hosts by inspecting the emulated BIOS. 183 */ 184static enum VM_GUEST 185detect_virtual(void) 186{ 187 char *sysenv; 188 int i; 189 190 sysenv = getenv("smbios.bios.vendor"); 191 if (sysenv != NULL) { 192 for (i = 0; vm_bnames[i] != NULL; i++) 193 if (strcmp(sysenv, vm_bnames[i]) == 0) { 194 freeenv(sysenv); 195 return (VM_GUEST_VM); 196 } 197 freeenv(sysenv); 198 } 199 sysenv = getenv("smbios.system.product"); 200 if (sysenv != NULL) { 201 for (i = 0; vm_pnames[i] != NULL; i++) 202 if (strcmp(sysenv, vm_pnames[i]) == 0) { 203 freeenv(sysenv); 204 return (VM_GUEST_VM); 205 } 206 freeenv(sysenv); 207 } 208 return (VM_GUEST_NO); 209} 210#endif 211 212/* 213 * Boot time overrides that are not scaled against main memory 214 */ 215void 216init_param1(void) 217{ 218#ifndef XEN 219 vm_guest = detect_virtual(); 220#else 221 vm_guest = VM_GUEST_XEN; 222#endif 223 hz = -1; 224 TUNABLE_INT_FETCH("kern.hz", &hz); 225 if (hz == -1) 226 hz = vm_guest > VM_GUEST_NO ? HZ_VM : HZ; 227 tick = 1000000 / hz; 228 229#ifdef VM_SWZONE_SIZE_MAX 230 maxswzone = VM_SWZONE_SIZE_MAX; 231#endif 232 TUNABLE_LONG_FETCH("kern.maxswzone", &maxswzone); 233#ifdef VM_BCACHE_SIZE_MAX 234 maxbcache = VM_BCACHE_SIZE_MAX; 235#endif 236 TUNABLE_LONG_FETCH("kern.maxbcache", &maxbcache); 237 msgbufsize = MSGBUF_SIZE; 238 TUNABLE_INT_FETCH("kern.msgbufsize", &msgbufsize); 239 240 maxtsiz = MAXTSIZ; 241 TUNABLE_ULONG_FETCH("kern.maxtsiz", &maxtsiz); 242 dfldsiz = DFLDSIZ; 243 TUNABLE_ULONG_FETCH("kern.dfldsiz", &dfldsiz); 244 maxdsiz = MAXDSIZ; 245 TUNABLE_ULONG_FETCH("kern.maxdsiz", &maxdsiz); 246 dflssiz = DFLSSIZ; 247 TUNABLE_ULONG_FETCH("kern.dflssiz", &dflssiz); 248 maxssiz = MAXSSIZ; 249 TUNABLE_ULONG_FETCH("kern.maxssiz", &maxssiz); 250 sgrowsiz = SGROWSIZ; 251 TUNABLE_ULONG_FETCH("kern.sgrowsiz", &sgrowsiz); 252 253 /* 254 * Let the administrator set {NGROUPS_MAX}, but disallow values 255 * less than NGROUPS_MAX which would violate POSIX.1-2008 or 256 * greater than INT_MAX-1 which would result in overflow. 257 */ 258 ngroups_max = NGROUPS_MAX; 259 TUNABLE_INT_FETCH("kern.ngroups", &ngroups_max); 260 if (ngroups_max < NGROUPS_MAX) 261 ngroups_max = NGROUPS_MAX; 262 263 /* 264 * Only allow to lower the maximal pid. 265 * Prevent setting up a non-bootable system if pid_max is too low. 266 */ 267 TUNABLE_INT_FETCH("kern.pid_max", &pid_max); 268 if (pid_max > PID_MAX) 269 pid_max = PID_MAX; 270 else if (pid_max < 300) 271 pid_max = 300; 272 273 TUNABLE_INT_FETCH("vfs.unmapped_buf_allowed", &unmapped_buf_allowed); 274} 275 276/* 277 * Boot time overrides that are scaled against main memory 278 */ 279void 280init_param2(long physpages) 281{ 282 283 /* Base parameters */ 284 maxusers = MAXUSERS; 285 TUNABLE_INT_FETCH("kern.maxusers", &maxusers); 286 if (maxusers == 0) { 287 maxusers = physpages / (2 * 1024 * 1024 / PAGE_SIZE); 288 if (maxusers < 32) 289 maxusers = 32; 290#ifdef VM_MAX_AUTOTUNE_MAXUSERS 291 if (maxusers > VM_MAX_AUTOTUNE_MAXUSERS) 292 maxusers = VM_MAX_AUTOTUNE_MAXUSERS; 293#endif 294 /* 295 * Scales down the function in which maxusers grows once 296 * we hit 384. 297 */ 298 if (maxusers > 384) 299 maxusers = 384 + ((maxusers - 384) / 8); 300 } 301 302 /* 303 * The following can be overridden after boot via sysctl. Note: 304 * unless overriden, these macros are ultimately based on maxusers. 305 * Limit maxproc so that kmap entries cannot be exhausted by 306 * processes. 307 */ 308 maxproc = NPROC; 309 TUNABLE_INT_FETCH("kern.maxproc", &maxproc); 310 if (maxproc > (physpages / 12)) 311 maxproc = physpages / 12; 312 maxprocperuid = (maxproc * 9) / 10; 313 314 /* 315 * The default limit for maxfiles is 1/12 of the number of 316 * physical page but not less than 16 times maxusers. 317 * At most it can be 1/6 the number of physical pages. 318 */ 319 maxfiles = imax(MAXFILES, physpages / 8); 320 TUNABLE_INT_FETCH("kern.maxfiles", &maxfiles); 321 if (maxfiles > (physpages / 4)) 322 maxfiles = physpages / 4; 323 maxfilesperproc = (maxfiles / 10) * 9; 324 325 /* 326 * Cannot be changed after boot. 327 */ 328 nbuf = NBUF; 329 TUNABLE_INT_FETCH("kern.nbuf", &nbuf); 330 TUNABLE_INT_FETCH("kern.bio_transient_maxcnt", &bio_transient_maxcnt); 331 332 /* 333 * XXX: Does the callout wheel have to be so big? 334 * 335 * Clip callout to result of previous function of maxusers maximum 336 * 384. This is still huge, but acceptable. 337 */ 338 ncallout = imin(16 + maxproc + maxfiles, 18508); 339 TUNABLE_INT_FETCH("kern.ncallout", &ncallout); 340 341 /* 342 * The default for maxpipekva is min(1/64 of the kernel address space, 343 * max(1/64 of main memory, 512KB)). See sys_pipe.c for more details. 344 */ 345 maxpipekva = (physpages / 64) * PAGE_SIZE; 346 TUNABLE_LONG_FETCH("kern.ipc.maxpipekva", &maxpipekva); 347 if (maxpipekva < 512 * 1024) 348 maxpipekva = 512 * 1024; 349 if (maxpipekva > (VM_MAX_KERNEL_ADDRESS - VM_MIN_KERNEL_ADDRESS) / 64) 350 maxpipekva = (VM_MAX_KERNEL_ADDRESS - VM_MIN_KERNEL_ADDRESS) / 351 64; 352} 353 354/* 355 * Sysctl stringifying handler for kern.vm_guest. 356 */ 357static int 358sysctl_kern_vm_guest(SYSCTL_HANDLER_ARGS) 359{ 360 return (SYSCTL_OUT(req, vm_guest_sysctl_names[vm_guest], 361 strlen(vm_guest_sysctl_names[vm_guest]))); 362} 363