1 /* $NetBSD: xen_ipi.c,v 1.5 2011/09/27 01:02:37 jym Exp $ */ 2 3 /*- 4 * Copyright (c) 2011 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Cherry G. Mathew <cherry@zyx.in> 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 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32 #include <sys/cdefs.h> /* RCS ID macro */ 33 34 /* 35 * Based on: x86/ipi.c 36 * __KERNEL_RCSID(0, "$NetBSD: xen_ipi.c,v 1.5 2011/09/27 01:02:37 jym Exp $"); 37 */ 38 39 __KERNEL_RCSID(0, "$NetBSD: xen_ipi.c,v 1.5 2011/09/27 01:02:37 jym Exp $"); 40 41 #include <sys/types.h> 42 43 #include <sys/atomic.h> 44 #include <sys/mutex.h> 45 #include <sys/cpu.h> 46 #include <sys/device.h> 47 #include <sys/xcall.h> 48 #include <sys/errno.h> 49 #include <sys/systm.h> 50 51 #include <machine/cpu.h> 52 #ifdef __x86_64__ 53 #include <machine/fpu.h> 54 #else 55 #include <machine/npx.h> 56 #endif /* __x86_64__ */ 57 #include <machine/frame.h> 58 #include <machine/segments.h> 59 60 #include <xen/intr.h> 61 #include <xen/intrdefs.h> 62 #include <xen/hypervisor.h> 63 #include <xen/xen3-public/vcpu.h> 64 65 #ifdef __x86_64__ 66 extern void ddb_ipi(struct trapframe); 67 #else 68 extern void ddb_ipi(int, struct trapframe); 69 #endif /* __x86_64__ */ 70 71 static void xen_ipi_halt(struct cpu_info *, struct intrframe *); 72 static void xen_ipi_synch_fpu(struct cpu_info *, struct intrframe *); 73 static void xen_ipi_ddb(struct cpu_info *, struct intrframe *); 74 static void xen_ipi_xcall(struct cpu_info *, struct intrframe *); 75 76 static void (*ipifunc[XEN_NIPIS])(struct cpu_info *, struct intrframe *) = 77 { /* In order of priority (see: xen/include/intrdefs.h */ 78 xen_ipi_halt, 79 xen_ipi_synch_fpu, 80 xen_ipi_ddb, 81 xen_ipi_xcall 82 }; 83 84 static void 85 xen_ipi_handler(struct cpu_info *ci, struct intrframe *regs) 86 { 87 uint32_t pending; 88 int bit; 89 90 pending = atomic_swap_32(&ci->ci_ipis, 0); 91 92 KDASSERT((pending >> XEN_NIPIS) == 0); 93 while ((bit = ffs(pending)) != 0) { 94 bit--; 95 pending &= ~(1 << bit); 96 ci->ci_ipi_events[bit].ev_count++; 97 if (ipifunc[bit] != NULL) { 98 (*ipifunc[bit])(ci, regs); 99 } else { 100 panic("ipifunc[%d] unsupported!\n", bit); 101 /* NOTREACHED */ 102 } 103 } 104 } 105 106 /* Must be called once for every cpu that expects to send/recv ipis */ 107 void 108 xen_ipi_init(void) 109 { 110 cpuid_t vcpu; 111 evtchn_port_t evtchn; 112 struct cpu_info *ci; 113 114 ci = curcpu(); 115 116 vcpu = ci->ci_cpuid; 117 KASSERT(vcpu < MAX_VIRT_CPUS); 118 119 evtchn = bind_vcpu_to_evtch(vcpu); 120 ci->ci_ipi_evtchn = evtchn; 121 122 KASSERT(evtchn != -1 && evtchn < NR_EVENT_CHANNELS); 123 124 if (0 != event_set_handler(evtchn, (int (*)(void *))xen_ipi_handler, 125 ci, IPL_HIGH, "ipi")) { 126 panic("event_set_handler(...) KPI violation\n"); 127 /* NOTREACHED */ 128 } 129 130 hypervisor_enable_event(evtchn); 131 } 132 133 /* prefer this to global variable */ 134 static inline u_int max_cpus(void) 135 { 136 return maxcpus; 137 } 138 139 static inline bool /* helper */ 140 valid_ipimask(uint32_t ipimask) 141 { 142 uint32_t masks = XEN_IPI_XCALL | XEN_IPI_DDB | 143 XEN_IPI_SYNCH_FPU | XEN_IPI_HALT | 144 XEN_IPI_KICK; 145 146 if (ipimask & ~masks) { 147 return false; 148 } else { 149 return true; 150 } 151 152 } 153 154 int 155 xen_send_ipi(struct cpu_info *ci, uint32_t ipimask) 156 { 157 evtchn_port_t evtchn; 158 159 KASSERT(ci != NULL || ci != curcpu()); 160 161 if ((ci->ci_flags & CPUF_RUNNING) == 0) { 162 return ENOENT; 163 } 164 165 evtchn = ci->ci_ipi_evtchn; 166 167 KASSERTMSG(valid_ipimask(ipimask) == true, 168 "xen_send_ipi() called with invalid ipimask\n"); 169 170 atomic_or_32(&ci->ci_ipis, ipimask); 171 hypervisor_notify_via_evtchn(evtchn); 172 173 return 0; 174 } 175 176 void 177 xen_broadcast_ipi(uint32_t ipimask) 178 { 179 struct cpu_info *ci, *self = curcpu(); 180 CPU_INFO_ITERATOR cii; 181 182 KASSERTMSG(valid_ipimask(ipimask) == true, 183 "xen_broadcast_ipi() called with invalid ipimask\n"); 184 185 /* 186 * XXX-cherry: there's an implicit broadcast sending order 187 * which I dislike. Randomise this ? :-) 188 */ 189 190 for (CPU_INFO_FOREACH(cii, ci)) { 191 if (ci == NULL) 192 continue; 193 if (ci == self) 194 continue; 195 if (ci->ci_data.cpu_idlelwp == NULL) 196 continue; 197 if ((ci->ci_flags & CPUF_PRESENT) == 0) 198 continue; 199 if (ci->ci_flags & (CPUF_RUNNING)) { 200 if (0 != xen_send_ipi(ci, ipimask)) { 201 panic("xen_ipi of %x from %s to %s failed\n", 202 ipimask, cpu_name(curcpu()), 203 cpu_name(ci)); 204 } 205 } 206 } 207 } 208 209 /* MD wrapper for the xcall(9) callback. */ 210 #define PRIuCPUID "lu" /* XXX: move this somewhere more appropriate */ 211 212 static void 213 xen_ipi_halt(struct cpu_info *ci, struct intrframe *intrf) 214 { 215 KASSERT(ci == curcpu()); 216 KASSERT(ci != NULL); 217 if (HYPERVISOR_vcpu_op(VCPUOP_down, ci->ci_cpuid, NULL)) { 218 panic("vcpu%" PRIuCPUID "shutdown failed.\n", ci->ci_cpuid); 219 } 220 221 } 222 223 static void 224 xen_ipi_synch_fpu(struct cpu_info *ci, struct intrframe *intrf) 225 { 226 KASSERT(ci != NULL); 227 KASSERT(intrf != NULL); 228 229 #ifdef __x86_64__ 230 fpusave_cpu(true); 231 #else 232 npxsave_cpu(true); 233 #endif /* __x86_64__ */ 234 } 235 236 static void 237 xen_ipi_ddb(struct cpu_info *ci, struct intrframe *intrf) 238 { 239 KASSERT(ci != NULL); 240 KASSERT(intrf != NULL); 241 242 #ifdef __x86_64__ 243 ddb_ipi(intrf->if_tf); 244 #else 245 struct trapframe tf; 246 tf.tf_gs = intrf->if_gs; 247 tf.tf_fs = intrf->if_fs; 248 tf.tf_es = intrf->if_es; 249 tf.tf_ds = intrf->if_ds; 250 tf.tf_edi = intrf->if_edi; 251 tf.tf_esi = intrf->if_esi; 252 tf.tf_ebp = intrf->if_ebp; 253 tf.tf_ebx = intrf->if_ebx; 254 tf.tf_ecx = intrf->if_ecx; 255 tf.tf_eax = intrf->if_eax; 256 tf.tf_trapno = intrf->__if_trapno; 257 tf.tf_err = intrf->__if_err; 258 tf.tf_eip = intrf->if_eip; 259 tf.tf_cs = intrf->if_cs; 260 tf.tf_eflags = intrf->if_eflags; 261 tf.tf_esp = intrf->if_esp; 262 tf.tf_ss = intrf->if_ss; 263 264 /* XXX: does i386/Xen have vm86 support ? 265 tf.tf_vm86_es; 266 tf.tf_vm86_ds; 267 tf.tf_vm86_fs; 268 tf.tf_vm86_gs; 269 :XXX */ 270 271 ddb_ipi(SEL_KPL, tf); 272 #endif 273 } 274 275 static void 276 xen_ipi_xcall(struct cpu_info *ci, struct intrframe *intrf) 277 { 278 KASSERT(ci != NULL); 279 KASSERT(intrf != NULL); 280 281 xc_ipi_handler(); 282 } 283 284 void 285 xc_send_ipi(struct cpu_info *ci) 286 { 287 288 KASSERT(kpreempt_disabled()); 289 KASSERT(curcpu() != ci); 290 printf("xc_send_ipi called \n"); 291 if (ci) { 292 if (0 != xen_send_ipi(ci, XEN_IPI_XCALL)) { 293 panic("xen_send_ipi(XEN_IPI_XCALL) failed\n"); 294 } 295 } else { 296 xen_broadcast_ipi(XEN_IPI_XCALL); 297 } 298 } 299