| 1 | /* $NetBSD: xen_ipi.c,v 1.20 2016/07/07 06:55:40 msaitoh 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 1.20 2016/07/07 06:55:40 msaitoh Exp $"); |
| 37 | */ |
| 38 | |
| 39 | __KERNEL_RCSID(0, "$NetBSD: xen_ipi.c,v 1.20 2016/07/07 06:55:40 msaitoh 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/ipi.h> |
| 49 | #include <sys/errno.h> |
| 50 | #include <sys/systm.h> |
| 51 | |
| 52 | #include <x86/fpu.h> |
| 53 | #include <machine/frame.h> |
| 54 | #include <machine/segments.h> |
| 55 | |
| 56 | #include <xen/evtchn.h> |
| 57 | #include <xen/intr.h> |
| 58 | #include <xen/intrdefs.h> |
| 59 | #include <xen/hypervisor.h> |
| 60 | #include <xen/xen-public/vcpu.h> |
| 61 | |
| 62 | #ifdef __x86_64__ |
| 63 | extern void ddb_ipi(struct trapframe); |
| 64 | #else |
| 65 | extern void ddb_ipi(int, struct trapframe); |
| 66 | #endif /* __x86_64__ */ |
| 67 | |
| 68 | static void xen_ipi_halt(struct cpu_info *, struct intrframe *); |
| 69 | static void xen_ipi_synch_fpu(struct cpu_info *, struct intrframe *); |
| 70 | static void xen_ipi_ddb(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 | xen_ipi_ddb, |
| 80 | xen_ipi_xcall, |
| 81 | xen_ipi_hvcb, |
| 82 | xen_ipi_generic, |
| 83 | }; |
| 84 | |
| 85 | static void |
| 86 | xen_ipi_handler(struct cpu_info *ci, struct intrframe *regs) |
| 87 | { |
| 88 | uint32_t pending; |
| 89 | int bit; |
| 90 | |
| 91 | pending = atomic_swap_32(&ci->ci_ipis, 0); |
| 92 | |
| 93 | KDASSERT((pending >> XEN_NIPIS) == 0); |
| 94 | while ((bit = ffs(pending)) != 0) { |
| 95 | bit--; |
| 96 | pending &= ~(1 << bit); |
| 97 | ci->ci_ipi_events[bit].ev_count++; |
| 98 | if (ipifunc[bit] != NULL) { |
| 99 | (*ipifunc[bit])(ci, regs); |
| 100 | } else { |
| 101 | panic("ipifunc[%d] unsupported!\n" , bit); |
| 102 | /* NOTREACHED */ |
| 103 | } |
| 104 | } |
| 105 | } |
| 106 | |
| 107 | /* Must be called once for every cpu that expects to send/recv ipis */ |
| 108 | void |
| 109 | xen_ipi_init(void) |
| 110 | { |
| 111 | cpuid_t vcpu; |
| 112 | evtchn_port_t evtchn; |
| 113 | struct cpu_info *ci; |
| 114 | |
| 115 | ci = curcpu(); |
| 116 | |
| 117 | vcpu = ci->ci_cpuid; |
| 118 | KASSERT(vcpu < XEN_LEGACY_MAX_VCPUS); |
| 119 | |
| 120 | evtchn = bind_vcpu_to_evtch(vcpu); |
| 121 | ci->ci_ipi_evtchn = evtchn; |
| 122 | |
| 123 | KASSERT(evtchn != -1 && evtchn < NR_EVENT_CHANNELS); |
| 124 | |
| 125 | if (0 != event_set_handler(evtchn, (int (*)(void *))xen_ipi_handler, |
| 126 | ci, IPL_HIGH, "ipi" )) { |
| 127 | panic("event_set_handler(...) KPI violation\n" ); |
| 128 | /* NOTREACHED */ |
| 129 | } |
| 130 | |
| 131 | hypervisor_enable_event(evtchn); |
| 132 | } |
| 133 | |
| 134 | #ifdef DIAGNOSTIC |
| 135 | static inline bool /* helper */ |
| 136 | valid_ipimask(uint32_t ipimask) |
| 137 | { |
| 138 | uint32_t masks = XEN_IPI_GENERIC | XEN_IPI_HVCB | XEN_IPI_XCALL | |
| 139 | XEN_IPI_DDB | XEN_IPI_SYNCH_FPU | |
| 140 | XEN_IPI_HALT | XEN_IPI_KICK; |
| 141 | |
| 142 | if (ipimask & ~masks) { |
| 143 | return false; |
| 144 | } else { |
| 145 | return true; |
| 146 | } |
| 147 | |
| 148 | } |
| 149 | #endif |
| 150 | |
| 151 | int |
| 152 | xen_send_ipi(struct cpu_info *ci, uint32_t ipimask) |
| 153 | { |
| 154 | evtchn_port_t evtchn; |
| 155 | |
| 156 | KASSERT(ci != NULL || ci != curcpu()); |
| 157 | |
| 158 | if ((ci->ci_flags & CPUF_RUNNING) == 0) { |
| 159 | return ENOENT; |
| 160 | } |
| 161 | |
| 162 | evtchn = ci->ci_ipi_evtchn; |
| 163 | |
| 164 | KASSERTMSG(valid_ipimask(ipimask) == true, |
| 165 | "xen_send_ipi() called with invalid ipimask\n" ); |
| 166 | |
| 167 | atomic_or_32(&ci->ci_ipis, ipimask); |
| 168 | hypervisor_notify_via_evtchn(evtchn); |
| 169 | |
| 170 | return 0; |
| 171 | } |
| 172 | |
| 173 | void |
| 174 | xen_broadcast_ipi(uint32_t ipimask) |
| 175 | { |
| 176 | struct cpu_info *ci, *self = curcpu(); |
| 177 | CPU_INFO_ITERATOR cii; |
| 178 | |
| 179 | KASSERTMSG(valid_ipimask(ipimask) == true, |
| 180 | "xen_broadcast_ipi() called with invalid ipimask\n" ); |
| 181 | |
| 182 | /* |
| 183 | * XXX-cherry: there's an implicit broadcast sending order |
| 184 | * which I dislike. Randomise this ? :-) |
| 185 | */ |
| 186 | |
| 187 | for (CPU_INFO_FOREACH(cii, ci)) { |
| 188 | if (ci == NULL) |
| 189 | continue; |
| 190 | if (ci == self) |
| 191 | continue; |
| 192 | if (ci->ci_data.cpu_idlelwp == NULL) |
| 193 | continue; |
| 194 | if ((ci->ci_flags & CPUF_PRESENT) == 0) |
| 195 | continue; |
| 196 | if (ci->ci_flags & (CPUF_RUNNING)) { |
| 197 | if (0 != xen_send_ipi(ci, ipimask)) { |
| 198 | panic("xen_ipi of %x from %s to %s failed\n" , |
| 199 | ipimask, cpu_name(curcpu()), |
| 200 | cpu_name(ci)); |
| 201 | } |
| 202 | } |
| 203 | } |
| 204 | } |
| 205 | |
| 206 | /* MD wrapper for the xcall(9) callback. */ |
| 207 | #define PRIuCPUID "lu" /* XXX: move this somewhere more appropriate */ |
| 208 | |
| 209 | static void |
| 210 | xen_ipi_halt(struct cpu_info *ci, struct intrframe *intrf) |
| 211 | { |
| 212 | KASSERT(ci == curcpu()); |
| 213 | KASSERT(ci != NULL); |
| 214 | if (HYPERVISOR_vcpu_op(VCPUOP_down, ci->ci_cpuid, NULL)) { |
| 215 | panic("vcpu%" PRIuCPUID "shutdown failed.\n" , ci->ci_cpuid); |
| 216 | } |
| 217 | |
| 218 | } |
| 219 | |
| 220 | static void |
| 221 | xen_ipi_synch_fpu(struct cpu_info *ci, struct intrframe *intrf) |
| 222 | { |
| 223 | KASSERT(ci != NULL); |
| 224 | KASSERT(intrf != NULL); |
| 225 | |
| 226 | fpusave_cpu(true); |
| 227 | } |
| 228 | |
| 229 | static void |
| 230 | xen_ipi_ddb(struct cpu_info *ci, struct intrframe *intrf) |
| 231 | { |
| 232 | KASSERT(ci != NULL); |
| 233 | KASSERT(intrf != NULL); |
| 234 | |
| 235 | #ifdef __x86_64__ |
| 236 | ddb_ipi(intrf->if_tf); |
| 237 | #else |
| 238 | struct trapframe tf; |
| 239 | tf.tf_gs = intrf->if_gs; |
| 240 | tf.tf_fs = intrf->if_fs; |
| 241 | tf.tf_es = intrf->if_es; |
| 242 | tf.tf_ds = intrf->if_ds; |
| 243 | tf.tf_edi = intrf->if_edi; |
| 244 | tf.tf_esi = intrf->if_esi; |
| 245 | tf.tf_ebp = intrf->if_ebp; |
| 246 | tf.tf_ebx = intrf->if_ebx; |
| 247 | tf.tf_ecx = intrf->if_ecx; |
| 248 | tf.tf_eax = intrf->if_eax; |
| 249 | tf.tf_trapno = intrf->__if_trapno; |
| 250 | tf.tf_err = intrf->__if_err; |
| 251 | tf.tf_eip = intrf->if_eip; |
| 252 | tf.tf_cs = intrf->if_cs; |
| 253 | tf.tf_eflags = intrf->if_eflags; |
| 254 | tf.tf_esp = intrf->if_esp; |
| 255 | tf.tf_ss = intrf->if_ss; |
| 256 | |
| 257 | /* XXX: does i386/Xen have vm86 support ? |
| 258 | tf.tf_vm86_es; |
| 259 | tf.tf_vm86_ds; |
| 260 | tf.tf_vm86_fs; |
| 261 | tf.tf_vm86_gs; |
| 262 | :XXX */ |
| 263 | |
| 264 | ddb_ipi(SEL_KPL, tf); |
| 265 | #endif |
| 266 | } |
| 267 | |
| 268 | static void |
| 269 | xen_ipi_xcall(struct cpu_info *ci, struct intrframe *intrf) |
| 270 | { |
| 271 | KASSERT(ci != NULL); |
| 272 | KASSERT(intrf != NULL); |
| 273 | |
| 274 | xc_ipi_handler(); |
| 275 | } |
| 276 | |
| 277 | void |
| 278 | xc_send_ipi(struct cpu_info *ci) |
| 279 | { |
| 280 | |
| 281 | KASSERT(kpreempt_disabled()); |
| 282 | KASSERT(curcpu() != ci); |
| 283 | if (ci) { |
| 284 | if (0 != xen_send_ipi(ci, XEN_IPI_XCALL)) { |
| 285 | panic("xen_send_ipi(XEN_IPI_XCALL) failed\n" ); |
| 286 | } |
| 287 | } else { |
| 288 | xen_broadcast_ipi(XEN_IPI_XCALL); |
| 289 | } |
| 290 | } |
| 291 | |
| 292 | static void |
| 293 | xen_ipi_generic(struct cpu_info *ci, struct intrframe *intrf) |
| 294 | { |
| 295 | KASSERT(ci != NULL); |
| 296 | KASSERT(intrf != NULL); |
| 297 | |
| 298 | ipi_cpu_handler(); |
| 299 | } |
| 300 | |
| 301 | void |
| 302 | cpu_ipi(struct cpu_info *ci) |
| 303 | { |
| 304 | KASSERT(kpreempt_disabled()); |
| 305 | KASSERT(curcpu() != ci); |
| 306 | if (ci) { |
| 307 | if (0 != xen_send_ipi(ci, XEN_IPI_GENERIC)) { |
| 308 | panic("xen_send_ipi(XEN_IPI_GENERIC) failed\n" ); |
| 309 | } |
| 310 | } else { |
| 311 | xen_broadcast_ipi(XEN_IPI_GENERIC); |
| 312 | } |
| 313 | } |
| 314 | |
| 315 | static void |
| 316 | xen_ipi_hvcb(struct cpu_info *ci, struct intrframe *intrf) |
| 317 | { |
| 318 | KASSERT(ci != NULL); |
| 319 | KASSERT(intrf != NULL); |
| 320 | KASSERT(ci == curcpu()); |
| 321 | KASSERT(!ci->ci_vcpu->evtchn_upcall_mask); |
| 322 | |
| 323 | hypervisor_force_callback(); |
| 324 | } |
| 325 | |