1 /***************************************************************************** 2 * i386/xen/xen-os.h 3 * 4 * Random collection of macros and definition 5 * 6 * Copyright (c) 2003, 2004 Keir Fraser (on behalf of the Xen team) 7 * All rights reserved. 8 * 9 * Permission is hereby granted, free of charge, to any person obtaining a copy 10 * of this software and associated documentation files (the "Software"), to 11 * deal in the Software without restriction, including without limitation the 12 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or 13 * sell copies of the Software, and to permit persons to whom the Software is 14 * furnished to do so, subject to the following conditions: 15 * 16 * The above copyright notice and this permission notice shall be included in 17 * all copies or substantial portions of the Software. 18 * 19 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 20 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 21 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 22 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 23 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING 24 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER 25 * DEALINGS IN THE SOFTWARE. 26 * 27 * $FreeBSD$ 28 */ 29 30 #ifndef _MACHINE_XEN_XEN_OS_H_ 31 #define _MACHINE_XEN_XEN_OS_H_ 32 33 #ifdef PAE 34 #define CONFIG_X86_PAE 35 #endif 36 37 /* Everything below this point is not included by assembler (.S) files. */ 38 #ifndef __ASSEMBLY__ 39 40 /* REP NOP (PAUSE) is a good thing to insert into busy-wait loops. */ 41 static inline void rep_nop(void) 42 { 43 __asm__ __volatile__ ( "rep;nop" : : : "memory" ); 44 } 45 #define cpu_relax() rep_nop() 46 47 #ifndef XENHVM 48 void xc_printf(const char *fmt, ...); 49 50 #ifdef SMP 51 extern int gdtset; 52 53 #include <sys/time.h> /* XXX for pcpu.h */ 54 #include <sys/pcpu.h> /* XXX for PCPU_GET */ 55 static inline int 56 smp_processor_id(void) 57 { 58 if (__predict_true(gdtset)) 59 return PCPU_GET(cpuid); 60 return 0; 61 } 62 63 #else 64 #define smp_processor_id() 0 65 #endif 66 67 #ifndef PANIC_IF 68 #define PANIC_IF(exp) if (__predict_false(exp)) {printf("panic - %s: %s:%d\n",#exp, __FILE__, __LINE__); panic("%s: %s:%d", #exp, __FILE__, __LINE__);} 69 #endif 70 71 /* 72 * Crude memory allocator for memory allocation early in boot. 73 */ 74 void *bootmem_alloc(unsigned int size); 75 void bootmem_free(void *ptr, unsigned int size); 76 77 /* 78 * STI/CLI equivalents. These basically set and clear the virtual 79 * event_enable flag in the shared_info structure. Note that when 80 * the enable bit is set, there may be pending events to be handled. 81 * We may therefore call into do_hypervisor_callback() directly. 82 */ 83 84 #define __cli() \ 85 do { \ 86 vcpu_info_t *_vcpu; \ 87 _vcpu = &HYPERVISOR_shared_info->vcpu_info[smp_processor_id()]; \ 88 _vcpu->evtchn_upcall_mask = 1; \ 89 barrier(); \ 90 } while (0) 91 92 #define __sti() \ 93 do { \ 94 vcpu_info_t *_vcpu; \ 95 barrier(); \ 96 _vcpu = &HYPERVISOR_shared_info->vcpu_info[smp_processor_id()]; \ 97 _vcpu->evtchn_upcall_mask = 0; \ 98 barrier(); /* unmask then check (avoid races) */ \ 99 if (__predict_false(_vcpu->evtchn_upcall_pending)) \ 100 force_evtchn_callback(); \ 101 } while (0) 102 103 #define __restore_flags(x) \ 104 do { \ 105 vcpu_info_t *_vcpu; \ 106 barrier(); \ 107 _vcpu = &HYPERVISOR_shared_info->vcpu_info[smp_processor_id()]; \ 108 if ((_vcpu->evtchn_upcall_mask = (x)) == 0) { \ 109 barrier(); /* unmask then check (avoid races) */ \ 110 if (__predict_false(_vcpu->evtchn_upcall_pending)) \ 111 force_evtchn_callback(); \ 112 } \ 113 } while (0) 114 115 /* 116 * Add critical_{enter, exit}? 117 * 118 */ 119 #define __save_and_cli(x) \ 120 do { \ 121 vcpu_info_t *_vcpu; \ 122 _vcpu = &HYPERVISOR_shared_info->vcpu_info[smp_processor_id()]; \ 123 (x) = _vcpu->evtchn_upcall_mask; \ 124 _vcpu->evtchn_upcall_mask = 1; \ 125 barrier(); \ 126 } while (0) 127 128 129 #define cli() __cli() 130 #define sti() __sti() 131 #define save_flags(x) __save_flags(x) 132 #define restore_flags(x) __restore_flags(x) 133 #define save_and_cli(x) __save_and_cli(x) 134 135 #define local_irq_save(x) __save_and_cli(x) 136 #define local_irq_restore(x) __restore_flags(x) 137 #define local_irq_disable() __cli() 138 #define local_irq_enable() __sti() 139 140 #define mtx_lock_irqsave(lock, x) {local_irq_save((x)); mtx_lock_spin((lock));} 141 #define mtx_unlock_irqrestore(lock, x) {mtx_unlock_spin((lock)); local_irq_restore((x)); } 142 #define spin_lock_irqsave mtx_lock_irqsave 143 #define spin_unlock_irqrestore mtx_unlock_irqrestore 144 145 #endif /* !XENHVM */ 146 147 /* This is a barrier for the compiler only, NOT the processor! */ 148 #define barrier() __asm__ __volatile__("": : :"memory") 149 150 #define LOCK_PREFIX "" 151 #define LOCK "" 152 #define ADDR (*(volatile long *) addr) 153 /* 154 * Make sure gcc doesn't try to be clever and move things around 155 * on us. We need to use _exactly_ the address the user gave us, 156 * not some alias that contains the same information. 157 */ 158 typedef struct { volatile int counter; } atomic_t; 159 160 #define xen_xchg(ptr,v) \ 161 ((__typeof__(*(ptr)))__xchg((unsigned long)(v),(ptr),sizeof(*(ptr)))) 162 struct __xchg_dummy { unsigned long a[100]; }; 163 #define __xg(x) ((volatile struct __xchg_dummy *)(x)) 164 static __inline unsigned long __xchg(unsigned long x, volatile void * ptr, 165 int size) 166 { 167 switch (size) { 168 case 1: 169 __asm__ __volatile__("xchgb %b0,%1" 170 :"=q" (x) 171 :"m" (*__xg(ptr)), "0" (x) 172 :"memory"); 173 break; 174 case 2: 175 __asm__ __volatile__("xchgw %w0,%1" 176 :"=r" (x) 177 :"m" (*__xg(ptr)), "0" (x) 178 :"memory"); 179 break; 180 case 4: 181 __asm__ __volatile__("xchgl %0,%1" 182 :"=r" (x) 183 :"m" (*__xg(ptr)), "0" (x) 184 :"memory"); 185 break; 186 } 187 return x; 188 } 189 190 /** 191 * test_and_clear_bit - Clear a bit and return its old value 192 * @nr: Bit to set 193 * @addr: Address to count from 194 * 195 * This operation is atomic and cannot be reordered. 196 * It also implies a memory barrier. 197 */ 198 static __inline int test_and_clear_bit(int nr, volatile void * addr) 199 { 200 int oldbit; 201 202 __asm__ __volatile__( LOCK_PREFIX 203 "btrl %2,%1\n\tsbbl %0,%0" 204 :"=r" (oldbit),"=m" (ADDR) 205 :"Ir" (nr) : "memory"); 206 return oldbit; 207 } 208 209 static __inline int constant_test_bit(int nr, const volatile void * addr) 210 { 211 return ((1UL << (nr & 31)) & (((const volatile unsigned int *) addr)[nr >> 5])) != 0; 212 } 213 214 static __inline int variable_test_bit(int nr, volatile void * addr) 215 { 216 int oldbit; 217 218 __asm__ __volatile__( 219 "btl %2,%1\n\tsbbl %0,%0" 220 :"=r" (oldbit) 221 :"m" (ADDR),"Ir" (nr)); 222 return oldbit; 223 } 224 225 #define test_bit(nr,addr) \ 226 (__builtin_constant_p(nr) ? \ 227 constant_test_bit((nr),(addr)) : \ 228 variable_test_bit((nr),(addr))) 229 230 231 /** 232 * set_bit - Atomically set a bit in memory 233 * @nr: the bit to set 234 * @addr: the address to start counting from 235 * 236 * This function is atomic and may not be reordered. See __set_bit() 237 * if you do not require the atomic guarantees. 238 * Note that @nr may be almost arbitrarily large; this function is not 239 * restricted to acting on a single-word quantity. 240 */ 241 static __inline__ void set_bit(int nr, volatile void * addr) 242 { 243 __asm__ __volatile__( LOCK_PREFIX 244 "btsl %1,%0" 245 :"=m" (ADDR) 246 :"Ir" (nr)); 247 } 248 249 /** 250 * clear_bit - Clears a bit in memory 251 * @nr: Bit to clear 252 * @addr: Address to start counting from 253 * 254 * clear_bit() is atomic and may not be reordered. However, it does 255 * not contain a memory barrier, so if it is used for locking purposes, 256 * you should call smp_mb__before_clear_bit() and/or smp_mb__after_clear_bit() 257 * in order to ensure changes are visible on other processors. 258 */ 259 static __inline__ void clear_bit(int nr, volatile void * addr) 260 { 261 __asm__ __volatile__( LOCK_PREFIX 262 "btrl %1,%0" 263 :"=m" (ADDR) 264 :"Ir" (nr)); 265 } 266 267 /** 268 * atomic_inc - increment atomic variable 269 * @v: pointer of type atomic_t 270 * 271 * Atomically increments @v by 1. Note that the guaranteed 272 * useful range of an atomic_t is only 24 bits. 273 */ 274 static __inline__ void atomic_inc(atomic_t *v) 275 { 276 __asm__ __volatile__( 277 LOCK "incl %0" 278 :"=m" (v->counter) 279 :"m" (v->counter)); 280 } 281 282 283 #define rdtscll(val) \ 284 __asm__ __volatile__("rdtsc" : "=A" (val)) 285 286 #endif /* !__ASSEMBLY__ */ 287 288 #endif /* _MACHINE_XEN_XEN_OS_H_ */ 289