xen_ipi.c revision 1.13
1 /* $NetBSD: xen_ipi.c,v 1.13 2013/10/23 20:18:50 drochner 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 1.13 2013/10/23 20:18:50 drochner Exp $"); 37 */ 38 39 __KERNEL_RCSID(0, "$NetBSD: xen_ipi.c,v 1.13 2013/10/23 20:18:50 drochner Exp $"); 40 41 #include <sys/types.h> 42 43 #include <sys/atomic.h> 44 #include <sys/cpu.h> 45 #include <sys/mutex.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/frame.h> 52 #include <machine/segments.h> 53 54 #include <xen/evtchn.h> 55 #include <xen/intr.h> 56 #include <xen/intrdefs.h> 57 #include <xen/hypervisor.h> 58 #include <xen/xen-public/vcpu.h> 59 60 #ifdef __x86_64__ 61 extern void ddb_ipi(struct trapframe); 62 #else 63 extern void ddb_ipi(int, struct trapframe); 64 #endif /* __x86_64__ */ 65 66 static void xen_ipi_halt(struct cpu_info *, struct intrframe *); 67 static void xen_ipi_ddb(struct cpu_info *, struct intrframe *); 68 static void xen_ipi_xcall(struct cpu_info *, struct intrframe *); 69 static void xen_ipi_hvcb(struct cpu_info *, struct intrframe *); 70 71 static void (*ipifunc[XEN_NIPIS])(struct cpu_info *, struct intrframe *) = 72 { /* In order of priority (see: xen/include/intrdefs.h */ 73 xen_ipi_halt, 74 NULL, 75 xen_ipi_ddb, 76 xen_ipi_xcall, 77 xen_ipi_hvcb 78 }; 79 80 static void 81 xen_ipi_handler(struct cpu_info *ci, struct intrframe *regs) 82 { 83 uint32_t pending; 84 int bit; 85 86 pending = atomic_swap_32(&ci->ci_ipis, 0); 87 88 KDASSERT((pending >> XEN_NIPIS) == 0); 89 while ((bit = ffs(pending)) != 0) { 90 bit--; 91 pending &= ~(1 << bit); 92 ci->ci_ipi_events[bit].ev_count++; 93 if (ipifunc[bit] != NULL) { 94 (*ipifunc[bit])(ci, regs); 95 } else { 96 panic("ipifunc[%d] unsupported!\n", bit); 97 /* NOTREACHED */ 98 } 99 } 100 } 101 102 /* Must be called once for every cpu that expects to send/recv ipis */ 103 void 104 xen_ipi_init(void) 105 { 106 cpuid_t vcpu; 107 evtchn_port_t evtchn; 108 struct cpu_info *ci; 109 110 ci = curcpu(); 111 112 vcpu = ci->ci_cpuid; 113 KASSERT(vcpu < XEN_LEGACY_MAX_VCPUS); 114 115 evtchn = bind_vcpu_to_evtch(vcpu); 116 ci->ci_ipi_evtchn = evtchn; 117 118 KASSERT(evtchn != -1 && evtchn < NR_EVENT_CHANNELS); 119 120 if (0 != event_set_handler(evtchn, (int (*)(void *))xen_ipi_handler, 121 ci, IPL_HIGH, "ipi")) { 122 panic("event_set_handler(...) KPI violation\n"); 123 /* NOTREACHED */ 124 } 125 126 hypervisor_enable_event(evtchn); 127 } 128 129 static inline bool /* helper */ 130 valid_ipimask(uint32_t ipimask) 131 { 132 uint32_t masks = XEN_IPI_HVCB | XEN_IPI_XCALL | 133 XEN_IPI_DDB | XEN_IPI_SYNCH_FPU | 134 XEN_IPI_HALT | XEN_IPI_KICK; 135 136 if (ipimask & ~masks) { 137 return false; 138 } else { 139 return true; 140 } 141 142 } 143 144 int 145 xen_send_ipi(struct cpu_info *ci, uint32_t ipimask) 146 { 147 evtchn_port_t evtchn; 148 149 KASSERT(ci != NULL || ci != curcpu()); 150 151 if ((ci->ci_flags & CPUF_RUNNING) == 0) { 152 return ENOENT; 153 } 154 155 evtchn = ci->ci_ipi_evtchn; 156 157 KASSERTMSG(valid_ipimask(ipimask) == true, 158 "xen_send_ipi() called with invalid ipimask\n"); 159 160 atomic_or_32(&ci->ci_ipis, ipimask); 161 hypervisor_notify_via_evtchn(evtchn); 162 163 return 0; 164 } 165 166 void 167 xen_broadcast_ipi(uint32_t ipimask) 168 { 169 struct cpu_info *ci, *self = curcpu(); 170 CPU_INFO_ITERATOR cii; 171 172 KASSERTMSG(valid_ipimask(ipimask) == true, 173 "xen_broadcast_ipi() called with invalid ipimask\n"); 174 175 /* 176 * XXX-cherry: there's an implicit broadcast sending order 177 * which I dislike. Randomise this ? :-) 178 */ 179 180 for (CPU_INFO_FOREACH(cii, ci)) { 181 if (ci == NULL) 182 continue; 183 if (ci == self) 184 continue; 185 if (ci->ci_data.cpu_idlelwp == NULL) 186 continue; 187 if ((ci->ci_flags & CPUF_PRESENT) == 0) 188 continue; 189 if (ci->ci_flags & (CPUF_RUNNING)) { 190 if (0 != xen_send_ipi(ci, ipimask)) { 191 panic("xen_ipi of %x from %s to %s failed\n", 192 ipimask, cpu_name(curcpu()), 193 cpu_name(ci)); 194 } 195 } 196 } 197 } 198 199 /* MD wrapper for the xcall(9) callback. */ 200 #define PRIuCPUID "lu" /* XXX: move this somewhere more appropriate */ 201 202 static void 203 xen_ipi_halt(struct cpu_info *ci, struct intrframe *intrf) 204 { 205 KASSERT(ci == curcpu()); 206 KASSERT(ci != NULL); 207 if (HYPERVISOR_vcpu_op(VCPUOP_down, ci->ci_cpuid, NULL)) { 208 panic("vcpu%" PRIuCPUID "shutdown failed.\n", ci->ci_cpuid); 209 } 210 211 } 212 213 static void 214 xen_ipi_ddb(struct cpu_info *ci, struct intrframe *intrf) 215 { 216 KASSERT(ci != NULL); 217 KASSERT(intrf != NULL); 218 219 #ifdef __x86_64__ 220 ddb_ipi(intrf->if_tf); 221 #else 222 struct trapframe tf; 223 tf.tf_gs = intrf->if_gs; 224 tf.tf_fs = intrf->if_fs; 225 tf.tf_es = intrf->if_es; 226 tf.tf_ds = intrf->if_ds; 227 tf.tf_edi = intrf->if_edi; 228 tf.tf_esi = intrf->if_esi; 229 tf.tf_ebp = intrf->if_ebp; 230 tf.tf_ebx = intrf->if_ebx; 231 tf.tf_ecx = intrf->if_ecx; 232 tf.tf_eax = intrf->if_eax; 233 tf.tf_trapno = intrf->__if_trapno; 234 tf.tf_err = intrf->__if_err; 235 tf.tf_eip = intrf->if_eip; 236 tf.tf_cs = intrf->if_cs; 237 tf.tf_eflags = intrf->if_eflags; 238 tf.tf_esp = intrf->if_esp; 239 tf.tf_ss = intrf->if_ss; 240 241 /* XXX: does i386/Xen have vm86 support ? 242 tf.tf_vm86_es; 243 tf.tf_vm86_ds; 244 tf.tf_vm86_fs; 245 tf.tf_vm86_gs; 246 :XXX */ 247 248 ddb_ipi(SEL_KPL, tf); 249 #endif 250 } 251 252 static void 253 xen_ipi_xcall(struct cpu_info *ci, struct intrframe *intrf) 254 { 255 KASSERT(ci != NULL); 256 KASSERT(intrf != NULL); 257 258 xc_ipi_handler(); 259 } 260 261 void 262 xc_send_ipi(struct cpu_info *ci) 263 { 264 265 KASSERT(kpreempt_disabled()); 266 KASSERT(curcpu() != ci); 267 if (ci) { 268 if (0 != xen_send_ipi(ci, XEN_IPI_XCALL)) { 269 panic("xen_send_ipi(XEN_IPI_XCALL) failed\n"); 270 } 271 } else { 272 xen_broadcast_ipi(XEN_IPI_XCALL); 273 } 274 } 275 276 static void 277 xen_ipi_hvcb(struct cpu_info *ci, struct intrframe *intrf) 278 { 279 KASSERT(ci != NULL); 280 KASSERT(intrf != NULL); 281 KASSERT(ci == curcpu()); 282 KASSERT(!ci->ci_vcpu->evtchn_upcall_mask); 283 284 hypervisor_force_callback(); 285 } 286
Indexes created Tue Sep 30 20:09:53 GMT 2025