xen_ipi.c revision 1.23.2.1
1 /* $NetBSD: xen_ipi.c,v 1.23.2.1 2018/06/25 07:25:47 pgoyette 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 (at) 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 1.23.2.1 2018/06/25 07:25:47 pgoyette Exp $"); 37 */ 38 39 __KERNEL_RCSID(0, "$NetBSD: xen_ipi.c,v 1.23.2.1 2018/06/25 07:25:47 pgoyette Exp $"); 40 41 #include "opt_ddb.h" 42 43 #include <sys/types.h> 44 45 #include <sys/atomic.h> 46 #include <sys/cpu.h> 47 #include <sys/mutex.h> 48 #include <sys/device.h> 49 #include <sys/xcall.h> 50 #include <sys/ipi.h> 51 #include <sys/errno.h> 52 #include <sys/systm.h> 53 54 #include <x86/fpu.h> 55 #include <machine/frame.h> 56 #include <machine/segments.h> 57 58 #include <xen/evtchn.h> 59 #include <xen/intr.h> 60 #include <xen/intrdefs.h> 61 #include <xen/hypervisor.h> 62 #include <xen/xen-public/vcpu.h> 63 64 #ifdef DDB 65 extern void ddb_ipi(struct trapframe); 66 static void xen_ipi_ddb(struct cpu_info *, struct intrframe *); 67 #endif 68 69 static void xen_ipi_halt(struct cpu_info *, struct intrframe *); 70 static void xen_ipi_synch_fpu(struct cpu_info *, struct intrframe *); 71 static void xen_ipi_xcall(struct cpu_info *, struct intrframe *); 72 static void xen_ipi_hvcb(struct cpu_info *, struct intrframe *); 73 static void xen_ipi_generic(struct cpu_info *, struct intrframe *); 74 75 static void (*ipifunc[XEN_NIPIS])(struct cpu_info *, struct intrframe *) = 76 { /* In order of priority (see: xen/include/intrdefs.h */ 77 xen_ipi_halt, 78 xen_ipi_synch_fpu, 79 #ifdef DDB 80 xen_ipi_ddb, 81 #else 82 NULL, 83 #endif 84 xen_ipi_xcall, 85 xen_ipi_hvcb, 86 xen_ipi_generic, 87 }; 88 89 static int 90 xen_ipi_handler(void *arg) 91 { 92 uint32_t pending; 93 int bit; 94 struct cpu_info *ci; 95 struct intrframe *regs; 96 97 ci = curcpu(); 98 regs = arg; 99 100 pending = atomic_swap_32(&ci->ci_ipis, 0); 101 102 KDASSERT((pending >> XEN_NIPIS) == 0); 103 while ((bit = ffs(pending)) != 0) { 104 bit--; 105 pending &= ~(1 << bit); 106 ci->ci_ipi_events[bit].ev_count++; 107 if (ipifunc[bit] != NULL) { 108 (*ipifunc[bit])(ci, regs); 109 } else { 110 panic("ipifunc[%d] unsupported!\n", bit); 111 /* NOTREACHED */ 112 } 113 } 114 115 return 0; 116 } 117 118 /* Must be called once for every cpu that expects to send/recv ipis */ 119 void 120 xen_ipi_init(void) 121 { 122 cpuid_t vcpu; 123 evtchn_port_t evtchn; 124 struct cpu_info *ci; 125 char intr_xname[INTRDEVNAMEBUF]; 126 127 ci = curcpu(); 128 129 vcpu = ci->ci_cpuid; 130 KASSERT(vcpu < XEN_LEGACY_MAX_VCPUS); 131 132 evtchn = bind_vcpu_to_evtch(vcpu); 133 ci->ci_ipi_evtchn = evtchn; 134 135 KASSERT(evtchn != -1 && evtchn < NR_EVENT_CHANNELS); 136 137 snprintf(intr_xname, sizeof(intr_xname), "%s ipi", 138 device_xname(ci->ci_dev)); 139 140 if (intr_establish_xname(0, &xen_pic, evtchn, IST_LEVEL, IPL_HIGH, 141 xen_ipi_handler, ci, true, intr_xname) == NULL) { 142 panic("%s: unable to register ipi handler\n", __func__); 143 /* NOTREACHED */ 144 } 145 146 hypervisor_enable_event(evtchn); 147 } 148 149 #ifdef DIAGNOSTIC 150 static inline bool /* helper */ 151 valid_ipimask(uint32_t ipimask) 152 { 153 uint32_t masks = XEN_IPI_GENERIC | XEN_IPI_HVCB | XEN_IPI_XCALL | 154 XEN_IPI_DDB | XEN_IPI_SYNCH_FPU | 155 XEN_IPI_HALT | XEN_IPI_KICK; 156 157 if (ipimask & ~masks) { 158 return false; 159 } else { 160 return true; 161 } 162 163 } 164 #endif 165 166 int 167 xen_send_ipi(struct cpu_info *ci, uint32_t ipimask) 168 { 169 evtchn_port_t evtchn; 170 171 KASSERT(ci != NULL || ci != curcpu()); 172 173 if ((ci->ci_flags & CPUF_RUNNING) == 0) { 174 return ENOENT; 175 } 176 177 evtchn = ci->ci_ipi_evtchn; 178 179 KASSERTMSG(valid_ipimask(ipimask) == true, 180 "xen_send_ipi() called with invalid ipimask\n"); 181 182 atomic_or_32(&ci->ci_ipis, ipimask); 183 hypervisor_notify_via_evtchn(evtchn); 184 185 return 0; 186 } 187 188 void 189 xen_broadcast_ipi(uint32_t ipimask) 190 { 191 struct cpu_info *ci, *self = curcpu(); 192 CPU_INFO_ITERATOR cii; 193 194 KASSERTMSG(valid_ipimask(ipimask) == true, 195 "xen_broadcast_ipi() called with invalid ipimask\n"); 196 197 /* 198 * XXX-cherry: there's an implicit broadcast sending order 199 * which I dislike. Randomise this ? :-) 200 */ 201 202 for (CPU_INFO_FOREACH(cii, ci)) { 203 if (ci == NULL) 204 continue; 205 if (ci == self) 206 continue; 207 if (ci->ci_data.cpu_idlelwp == NULL) 208 continue; 209 if ((ci->ci_flags & CPUF_PRESENT) == 0) 210 continue; 211 if (ci->ci_flags & (CPUF_RUNNING)) { 212 if (0 != xen_send_ipi(ci, ipimask)) { 213 panic("xen_ipi of %x from %s to %s failed\n", 214 ipimask, cpu_name(curcpu()), 215 cpu_name(ci)); 216 } 217 } 218 } 219 } 220 221 /* MD wrapper for the xcall(9) callback. */ 222 223 static void 224 xen_ipi_halt(struct cpu_info *ci, struct intrframe *intrf) 225 { 226 KASSERT(ci == curcpu()); 227 KASSERT(ci != NULL); 228 if (HYPERVISOR_vcpu_op(VCPUOP_down, ci->ci_cpuid, NULL)) { 229 panic("%s shutdown failed.\n", device_xname(ci->ci_dev)); 230 } 231 232 } 233 234 static void 235 xen_ipi_synch_fpu(struct cpu_info *ci, struct intrframe *intrf) 236 { 237 KASSERT(ci != NULL); 238 KASSERT(intrf != NULL); 239 240 fpusave_cpu(true); 241 } 242 243 #ifdef DDB 244 static void 245 xen_ipi_ddb(struct cpu_info *ci, struct intrframe *intrf) 246 { 247 KASSERT(ci != NULL); 248 KASSERT(intrf != NULL); 249 250 #ifdef __x86_64__ 251 ddb_ipi(intrf->if_tf); 252 #else 253 struct trapframe tf; 254 tf.tf_gs = intrf->if_gs; 255 tf.tf_fs = intrf->if_fs; 256 tf.tf_es = intrf->if_es; 257 tf.tf_ds = intrf->if_ds; 258 tf.tf_edi = intrf->if_edi; 259 tf.tf_esi = intrf->if_esi; 260 tf.tf_ebp = intrf->if_ebp; 261 tf.tf_ebx = intrf->if_ebx; 262 tf.tf_ecx = intrf->if_ecx; 263 tf.tf_eax = intrf->if_eax; 264 tf.tf_trapno = intrf->__if_trapno; 265 tf.tf_err = intrf->__if_err; 266 tf.tf_eip = intrf->if_eip; 267 tf.tf_cs = intrf->if_cs; 268 tf.tf_eflags = intrf->if_eflags; 269 tf.tf_esp = intrf->if_esp; 270 tf.tf_ss = intrf->if_ss; 271 272 ddb_ipi(tf); 273 #endif 274 } 275 #endif /* DDB */ 276 277 static void 278 xen_ipi_xcall(struct cpu_info *ci, struct intrframe *intrf) 279 { 280 KASSERT(ci != NULL); 281 KASSERT(intrf != NULL); 282 283 xc_ipi_handler(); 284 } 285 286 void 287 xc_send_ipi(struct cpu_info *ci) 288 { 289 290 KASSERT(kpreempt_disabled()); 291 KASSERT(curcpu() != ci); 292 if (ci) { 293 if (0 != xen_send_ipi(ci, XEN_IPI_XCALL)) { 294 panic("xen_send_ipi(XEN_IPI_XCALL) failed\n"); 295 } 296 } else { 297 xen_broadcast_ipi(XEN_IPI_XCALL); 298 } 299 } 300 301 static void 302 xen_ipi_generic(struct cpu_info *ci, struct intrframe *intrf) 303 { 304 KASSERT(ci != NULL); 305 KASSERT(intrf != NULL); 306 307 ipi_cpu_handler(); 308 } 309 310 void 311 cpu_ipi(struct cpu_info *ci) 312 { 313 KASSERT(kpreempt_disabled()); 314 KASSERT(curcpu() != ci); 315 if (ci) { 316 if (0 != xen_send_ipi(ci, XEN_IPI_GENERIC)) { 317 panic("xen_send_ipi(XEN_IPI_GENERIC) failed\n"); 318 } 319 } else { 320 xen_broadcast_ipi(XEN_IPI_GENERIC); 321 } 322 } 323 324 static void 325 xen_ipi_hvcb(struct cpu_info *ci, struct intrframe *intrf) 326 { 327 KASSERT(ci != NULL); 328 KASSERT(intrf != NULL); 329 KASSERT(ci == curcpu()); 330 KASSERT(!ci->ci_vcpu->evtchn_upcall_mask); 331 332 hypervisor_force_callback(); 333 } 334
Indexes created Tue Sep 30 20:09:53 GMT 2025