xref: /freebsd/sys/x86/xen/hvm.c (revision d1d015864103b253b3fcb2f72a0da5b0cfeb31b6)
1 /*
2  * Copyright (c) 2008 Citrix Systems, Inc.
3  * Copyright (c) 2012 Spectra Logic Corporation
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS AS IS'' AND
16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  */
27 
28 #include <sys/cdefs.h>
29 __FBSDID("$FreeBSD$");
30 
31 #include <sys/param.h>
32 #include <sys/bus.h>
33 #include <sys/kernel.h>
34 #include <sys/malloc.h>
35 #include <sys/proc.h>
36 
37 #include <dev/pci/pcivar.h>
38 #include <machine/cpufunc.h>
39 
40 #include <xen/xen-os.h>
41 #include <xen/features.h>
42 #include <xen/gnttab.h>
43 #include <xen/hypervisor.h>
44 #include <xen/hvm.h>
45 #include <xen/xen_intr.h>
46 
47 #include <vm/vm.h>
48 #include <vm/pmap.h>
49 
50 #include <xen/interface/hvm/params.h>
51 #include <xen/interface/vcpu.h>
52 
53 static MALLOC_DEFINE(M_XENHVM, "xen_hvm", "Xen HVM PV Support");
54 
55 DPCPU_DEFINE(struct vcpu_info, vcpu_local_info);
56 DPCPU_DEFINE(struct vcpu_info *, vcpu_info);
57 
58 /*-------------------------------- Global Data -------------------------------*/
59 /**
60  * If non-zero, the hypervisor has been configured to use a direct
61  * IDT event callback for interrupt injection.
62  */
63 int xen_vector_callback_enabled;
64 
65 /*------------------ Hypervisor Access Shared Memory Regions -----------------*/
66 /** Hypercall table accessed via HYPERVISOR_*_op() methods. */
67 char *hypercall_stubs;
68 shared_info_t *HYPERVISOR_shared_info;
69 enum xen_domain_type xen_domain_type = XEN_NATIVE;
70 
71 static uint32_t
72 xen_hvm_cpuid_base(void)
73 {
74 	uint32_t base, regs[4];
75 
76 	for (base = 0x40000000; base < 0x40010000; base += 0x100) {
77 		do_cpuid(base, regs);
78 		if (!memcmp("XenVMMXenVMM", &regs[1], 12)
79 		    && (regs[0] - base) >= 2)
80 			return (base);
81 	}
82 	return (0);
83 }
84 
85 /*
86  * Allocate and fill in the hypcall page.
87  */
88 static int
89 xen_hvm_init_hypercall_stubs(void)
90 {
91 	uint32_t base, regs[4];
92 	int i;
93 
94 	base = xen_hvm_cpuid_base();
95 	if (base == 0)
96 		return (ENXIO);
97 
98 	if (hypercall_stubs == NULL) {
99 		do_cpuid(base + 1, regs);
100 		printf("XEN: Hypervisor version %d.%d detected.\n",
101 		    regs[0] >> 16, regs[0] & 0xffff);
102 	}
103 
104 	/*
105 	 * Find the hypercall pages.
106 	 */
107 	do_cpuid(base + 2, regs);
108 
109 	if (hypercall_stubs == NULL) {
110 		size_t call_region_size;
111 
112 		call_region_size = regs[0] * PAGE_SIZE;
113 		hypercall_stubs = malloc(call_region_size, M_XENHVM, M_NOWAIT);
114 		if (hypercall_stubs == NULL)
115 			panic("Unable to allocate Xen hypercall region");
116 	}
117 
118 	for (i = 0; i < regs[0]; i++)
119 		wrmsr(regs[1], vtophys(hypercall_stubs + i * PAGE_SIZE) + i);
120 
121 	return (0);
122 }
123 
124 static void
125 xen_hvm_init_shared_info_page(void)
126 {
127 	struct xen_add_to_physmap xatp;
128 
129 	if (HYPERVISOR_shared_info == NULL) {
130 		HYPERVISOR_shared_info = malloc(PAGE_SIZE, M_XENHVM, M_NOWAIT);
131 		if (HYPERVISOR_shared_info == NULL)
132 			panic("Unable to allocate Xen shared info page");
133 	}
134 
135 	xatp.domid = DOMID_SELF;
136 	xatp.idx = 0;
137 	xatp.space = XENMAPSPACE_shared_info;
138 	xatp.gpfn = vtophys(HYPERVISOR_shared_info) >> PAGE_SHIFT;
139 	if (HYPERVISOR_memory_op(XENMEM_add_to_physmap, &xatp))
140 		panic("HYPERVISOR_memory_op failed");
141 }
142 
143 /*
144  * Tell the hypervisor how to contact us for event channel callbacks.
145  */
146 void
147 xen_hvm_set_callback(device_t dev)
148 {
149 	struct xen_hvm_param xhp;
150 	int irq;
151 
152 	xhp.domid = DOMID_SELF;
153 	xhp.index = HVM_PARAM_CALLBACK_IRQ;
154 	if (xen_feature(XENFEAT_hvm_callback_vector) != 0) {
155 		int error;
156 
157 		xhp.value = HVM_CALLBACK_VECTOR(IDT_EVTCHN);
158 		error = HYPERVISOR_hvm_op(HVMOP_set_param, &xhp);
159 		if (error == 0) {
160 			xen_vector_callback_enabled = 1;
161 			return;
162 		}
163 		printf("Xen HVM callback vector registration failed (%d). "
164 		    "Falling back to emulated device interrupt\n", error);
165 	}
166 	xen_vector_callback_enabled = 0;
167 	if (dev == NULL) {
168 		/*
169 		 * Called from early boot or resume.
170 		 * xenpci will invoke us again later.
171 		 */
172 		return;
173 	}
174 
175 	irq = pci_get_irq(dev);
176 	if (irq < 16) {
177 		xhp.value = HVM_CALLBACK_GSI(irq);
178 	} else {
179 		u_int slot;
180 		u_int pin;
181 
182 		slot = pci_get_slot(dev);
183 		pin = pci_get_intpin(dev) - 1;
184 		xhp.value = HVM_CALLBACK_PCI_INTX(slot, pin);
185 	}
186 
187 	if (HYPERVISOR_hvm_op(HVMOP_set_param, &xhp) != 0)
188 		panic("Can't set evtchn callback");
189 }
190 
191 #define	XEN_MAGIC_IOPORT 0x10
192 enum {
193 	XMI_MAGIC			 = 0x49d2,
194 	XMI_UNPLUG_IDE_DISKS		 = 0x01,
195 	XMI_UNPLUG_NICS			 = 0x02,
196 	XMI_UNPLUG_IDE_EXCEPT_PRI_MASTER = 0x04
197 };
198 
199 static void
200 xen_hvm_disable_emulated_devices(void)
201 {
202 	if (inw(XEN_MAGIC_IOPORT) != XMI_MAGIC)
203 		return;
204 
205 	if (bootverbose)
206 		printf("XEN: Disabling emulated block and network devices\n");
207 	outw(XEN_MAGIC_IOPORT, XMI_UNPLUG_IDE_DISKS|XMI_UNPLUG_NICS);
208 }
209 
210 void
211 xen_hvm_suspend(void)
212 {
213 }
214 
215 void
216 xen_hvm_resume(void)
217 {
218 
219 	xen_hvm_init_hypercall_stubs();
220 	xen_hvm_init_shared_info_page();
221 }
222 
223 static void
224 xen_hvm_init(void *dummy __unused)
225 {
226 
227 	if (xen_hvm_init_hypercall_stubs() != 0)
228 		return;
229 
230 	xen_domain_type = XEN_HVM_DOMAIN;
231 	setup_xen_features();
232 	xen_hvm_init_shared_info_page();
233 	xen_hvm_set_callback(NULL);
234 	xen_hvm_disable_emulated_devices();
235 }
236 
237 void xen_hvm_init_cpu(void)
238 {
239 	struct vcpu_register_vcpu_info info;
240 	struct vcpu_info *vcpu_info;
241 	int cpu, rc;
242 
243 	cpu = PCPU_GET(acpi_id);
244 	vcpu_info = DPCPU_PTR(vcpu_local_info);
245 	info.mfn = vtophys(vcpu_info) >> PAGE_SHIFT;
246 	info.offset = vtophys(vcpu_info) - trunc_page(vtophys(vcpu_info));
247 
248 	rc = HYPERVISOR_vcpu_op(VCPUOP_register_vcpu_info, cpu, &info);
249 	if (rc != 0)
250 		DPCPU_SET(vcpu_info, &HYPERVISOR_shared_info->vcpu_info[cpu]);
251 	else
252 		DPCPU_SET(vcpu_info, vcpu_info);
253 }
254 
255 SYSINIT(xen_hvm_init, SI_SUB_HYPERVISOR, SI_ORDER_FIRST, xen_hvm_init, NULL);
256 SYSINIT(xen_hvm_init_cpu, SI_SUB_INTR, SI_ORDER_FIRST, xen_hvm_init_cpu, NULL);
257