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 * 3. 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 * $FreeBSD: src/sys/kern/subr_param.c,v 1.42.2.10 2002/03/09 21:05:47 silby Exp $ 36 */ 37 38 #include "opt_param.h" 39 #include "opt_maxusers.h" 40 41 #include <sys/param.h> 42 #include <sys/systm.h> 43 #include <sys/kernel.h> 44 #include <sys/malloc.h> 45 #include <sys/sysctl.h> 46 #include <vm/pmap.h> 47 #include <machine/vmparam.h> 48 49 /* 50 * System parameter formulae. 51 */ 52 53 #ifndef HZ_DEFAULT 54 #define HZ_DEFAULT 100 55 #endif 56 #define NPROC (20 + 16 * maxusers) 57 #ifndef NBUF 58 #define NBUF 0 59 #endif 60 #ifndef MAXFILES 61 #define MAXFILES (maxproc * 16) 62 #endif 63 #ifndef MAXPOSIXLOCKSPERUID 64 #define MAXPOSIXLOCKSPERUID (maxproc * 4) 65 #endif 66 67 static int sysctl_kern_vmm_guest(SYSCTL_HANDLER_ARGS); 68 69 int hz; 70 int stathz; 71 int profhz; 72 int ustick; /* tick interval in microseconds */ 73 int nstick; /* tick interval in nanoseconds */ 74 int maxusers; /* base tunable */ 75 int maxproc; /* maximum # of processes */ 76 int maxprocperuid; /* max # of procs per user */ 77 int maxfiles; /* system wide open files limit */ 78 int maxfilesrootres; /* descriptors reserved for root use */ 79 int minfilesperproc; /* per-proc min open files (safety) */ 80 int maxfilesperproc; /* per-proc open files limit */ 81 int maxfilesperuser; /* per-user open files limit */ 82 int maxposixlocksperuid; /* max # POSIX locks per uid */ 83 int ncallout; /* maximum # of timer events */ 84 int mbuf_wait = 32; /* mbuf sleep time in ticks */ 85 long nbuf; 86 long nswbuf_mem; 87 long nswbuf_kva; 88 long nswbuf_raw; 89 long maxswzone; /* max swmeta KVA storage */ 90 long maxbcache; /* max buffer cache KVA storage */ 91 enum vmm_guest_type vmm_guest = VMM_GUEST_NONE; /* Running as VM guest? */ 92 u_quad_t maxtsiz; /* max text size */ 93 u_quad_t dfldsiz; /* initial data size limit */ 94 u_quad_t maxdsiz; /* max data size */ 95 u_quad_t dflssiz; /* initial stack size limit */ 96 u_quad_t maxssiz; /* max stack size */ 97 u_quad_t sgrowsiz; /* amount to grow stack */ 98 99 SYSCTL_PROC(_kern, OID_AUTO, vmm_guest, CTLFLAG_RD | CTLTYPE_STRING, 100 NULL, 0, sysctl_kern_vmm_guest, "A", 101 "Virtual machine guest type"); 102 103 /* 104 * These have to be allocated somewhere; allocating 105 * them here forces loader errors if this file is omitted 106 * (if they've been externed everywhere else; hah!). 107 */ 108 struct buf *swbuf_mem; 109 struct buf *swbuf_kva; 110 struct buf *swbuf_raw; 111 112 struct vmm_bname { 113 const char *str; 114 enum vmm_guest_type type; 115 }; 116 117 static struct vmm_bname vmm_bnames[] = { 118 { "QEMU", VMM_GUEST_QEMU }, /* QEMU */ 119 { "Plex86", VMM_GUEST_PLEX86 }, /* Plex86 */ 120 { "Bochs", VMM_GUEST_BOCHS }, /* Bochs */ 121 { "Xen", VMM_GUEST_XEN }, /* Xen */ 122 { "BHYVE", VMM_GUEST_BHYVE }, /* bhyve */ 123 { "Seabios", VMM_GUEST_KVM}, /* KVM */ 124 { NULL, 0 } 125 }; 126 127 static struct vmm_bname vmm_pnames[] = { 128 { "VMware Virtual Platform", VMM_GUEST_VMWARE }, /* VMWare VM */ 129 { "Virtual Machine", VMM_GUEST_HYPERV }, /* MS Hyper-V */ 130 { "VirtualBox", VMM_GUEST_VBOX }, /* Sun VirtualBox */ 131 { "Parallels Virtual Platform", VMM_GUEST_PARALLELS }, /* Parallels VM */ 132 { "KVM", VMM_GUEST_KVM }, /* KVM */ 133 { NULL, 0 } 134 }; 135 136 static const char *const vmm_guest_sysctl_names[] = { 137 "none", 138 "qemu", 139 "plex86", 140 "bochs", 141 "xen", 142 "bhyve", 143 "kvm", 144 "vmware", 145 "hyperv", 146 "vbox", 147 "parallels", 148 "vkernel", 149 "unknown", 150 NULL 151 }; 152 CTASSERT(NELEM(vmm_guest_sysctl_names) - 1 == VMM_GUEST_LAST); 153 154 char vmm_vendor[16]; 155 SYSCTL_STRING(_kern, OID_AUTO, vmm_vendor, CTLFLAG_RD, vmm_vendor, 0, 156 "Virtual machine vendor"); 157 158 /* 159 * Detect known Virtual Machine hosts by inspecting the emulated BIOS. 160 */ 161 enum vmm_guest_type 162 detect_virtual(void) 163 { 164 char *sysenv; 165 int i; 166 167 sysenv = kgetenv("smbios.bios.vendor"); 168 if (sysenv != NULL) { 169 for (i = 0; vmm_bnames[i].str != NULL; i++) 170 if (strcmp(sysenv, vmm_bnames[i].str) == 0) { 171 kfreeenv(sysenv); 172 return (vmm_bnames[i].type); 173 } 174 kfreeenv(sysenv); 175 } 176 sysenv = kgetenv("smbios.system.product"); 177 if (sysenv != NULL) { 178 for (i = 0; vmm_pnames[i].str != NULL; i++) 179 if (strcmp(sysenv, vmm_pnames[i].str) == 0) { 180 kfreeenv(sysenv); 181 return (vmm_pnames[i].type); 182 } 183 kfreeenv(sysenv); 184 } 185 return (VMM_GUEST_NONE); 186 } 187 188 /* 189 * Boot time overrides that are not scaled against main memory 190 */ 191 void 192 init_param1(void) 193 { 194 hz = HZ_DEFAULT; 195 TUNABLE_INT_FETCH("kern.hz", &hz); 196 stathz = hz * 128 / 100; 197 profhz = stathz; 198 ustick = 1000000 / hz; 199 nstick = 1000000000 / hz; 200 /* can adjust 30ms in 60s */ 201 ntp_default_tick_delta = howmany(30000000, 60 * hz); 202 203 #ifdef VM_SWZONE_SIZE_MAX 204 maxswzone = VM_SWZONE_SIZE_MAX; 205 #endif 206 TUNABLE_LONG_FETCH("kern.maxswzone", &maxswzone); 207 #ifdef VM_BCACHE_SIZE_MAX 208 maxbcache = VM_BCACHE_SIZE_MAX; 209 #endif 210 TUNABLE_LONG_FETCH("kern.maxbcache", &maxbcache); 211 maxtsiz = MAXTSIZ; 212 TUNABLE_QUAD_FETCH("kern.maxtsiz", &maxtsiz); 213 dfldsiz = DFLDSIZ; 214 TUNABLE_QUAD_FETCH("kern.dfldsiz", &dfldsiz); 215 maxdsiz = MAXDSIZ; 216 TUNABLE_QUAD_FETCH("kern.maxdsiz", &maxdsiz); 217 dflssiz = DFLSSIZ; 218 TUNABLE_QUAD_FETCH("kern.dflssiz", &dflssiz); 219 maxssiz = MAXSSIZ; 220 TUNABLE_QUAD_FETCH("kern.maxssiz", &maxssiz); 221 sgrowsiz = SGROWSIZ; 222 TUNABLE_QUAD_FETCH("kern.sgrowsiz", &sgrowsiz); 223 } 224 225 /* 226 * Boot time overrides that are scaled against main memory 227 */ 228 void 229 init_param2(int physpages) 230 { 231 size_t limsize; 232 233 /* 234 * Calculate manually becaus the VM page queues / system is not set 235 * up yet. 236 */ 237 limsize = (size_t)physpages * PAGE_SIZE; 238 if (limsize > KvaSize) 239 limsize = KvaSize; 240 if (maxswzone > limsize / 2) /* maxswzone size (1/2 of phys mem) */ 241 maxswzone = limsize / 2; 242 243 limsize /= 1024 * 1024; /* smaller of KVM or physmem in MB */ 244 245 /* Base parameters */ 246 maxusers = MAXUSERS; 247 TUNABLE_INT_FETCH("kern.maxusers", &maxusers); 248 if (maxusers == 0) { 249 maxusers = limsize / 8; /* ~384 per 3G */ 250 if (maxusers < 32) 251 maxusers = 32; 252 /* no upper limit */ 253 } 254 255 /* 256 * The following can be overridden after boot via sysctl. Note: 257 * unless overriden, these macros are ultimately based on maxusers. 258 * 259 * Limit maxproc so that kmap entries cannot be exhausted by 260 * processes. This limitation can be a bit problematic because 261 * processes can have a wide range of complexity. 262 */ 263 maxproc = NPROC; 264 TUNABLE_INT_FETCH("kern.maxproc", &maxproc); 265 if (maxproc < 32) 266 maxproc = 32; 267 if (maxproc > limsize * 40) 268 maxproc = limsize * 40; 269 270 /* 271 * Maximum number of open files 272 */ 273 maxfiles = MAXFILES; 274 TUNABLE_INT_FETCH("kern.maxfiles", &maxfiles); 275 if (maxfiles < 128) 276 maxfiles = 128; 277 278 /* 279 * Limit file descriptors so no single user can exhaust the 280 * system. 281 * 282 * WARNING: Do not set minfilesperproc too high or the user 283 * can exhaust the system with a combination of fork() 284 * and open(). Actual worst case is: 285 * 286 * (minfilesperproc * maxprocperuid) + maxfilesperuser 287 */ 288 maxprocperuid = maxproc / 4; 289 if (maxprocperuid < 128) 290 maxprocperuid = maxproc / 2; 291 minfilesperproc = 8; 292 maxfilesperproc = maxfiles / 4; 293 maxfilesperuser = maxfilesperproc * 2; 294 maxfilesrootres = maxfiles / 20; 295 296 /* 297 * Severe hack to try to prevent pipe() descriptors from 298 * blowing away kernel memory. 299 */ 300 if (KvaSize <= (vm_offset_t)(1536LL * 1024 * 1024) && 301 maxfilesperuser > 20000) { 302 maxfilesperuser = 20000; 303 } 304 305 maxposixlocksperuid = MAXPOSIXLOCKSPERUID; 306 TUNABLE_INT_FETCH("kern.maxposixlocksperuid", &maxposixlocksperuid); 307 308 /* 309 * Unless overriden, NBUF is typically 0 (auto-sized later). 310 */ 311 nbuf = NBUF; 312 TUNABLE_LONG_FETCH("kern.nbuf", &nbuf); 313 314 /* 315 * Calculate the size of the callout wheel. Limit to approximately 316 * 5 minutes worth of table (maxproc would have to be pretty huge), 317 * as more is not likely to gain us anything. 318 */ 319 ncallout = 16 + maxproc + maxfiles; 320 if (ncallout > 5*60*hz) 321 ncallout = 5*60*hz; 322 TUNABLE_INT_FETCH("kern.ncallout", &ncallout); 323 } 324 325 /* 326 * Sysctl stringifying handler for kern.vmm_guest. 327 */ 328 static int 329 sysctl_kern_vmm_guest(SYSCTL_HANDLER_ARGS) 330 { 331 return (SYSCTL_OUT(req, vmm_guest_sysctl_names[vmm_guest], 332 strlen(vmm_guest_sysctl_names[vmm_guest]))); 333 } 334