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-rw-r--r--virt/kvm/coalesced_mmio.c156
-rw-r--r--virt/kvm/coalesced_mmio.h23
-rw-r--r--virt/kvm/kvm_main.c57
3 files changed, 236 insertions, 0 deletions
diff --git a/virt/kvm/coalesced_mmio.c b/virt/kvm/coalesced_mmio.c
new file mode 100644
index 000000000000..5ae620d32fac
--- /dev/null
+++ b/virt/kvm/coalesced_mmio.c
@@ -0,0 +1,156 @@
1/*
2 * KVM coalesced MMIO
3 *
4 * Copyright (c) 2008 Bull S.A.S.
5 *
6 * Author: Laurent Vivier <Laurent.Vivier@bull.net>
7 *
8 */
9
10#include "iodev.h"
11
12#include <linux/kvm_host.h>
13#include <linux/kvm.h>
14
15#include "coalesced_mmio.h"
16
17static int coalesced_mmio_in_range(struct kvm_io_device *this,
18 gpa_t addr, int len, int is_write)
19{
20 struct kvm_coalesced_mmio_dev *dev =
21 (struct kvm_coalesced_mmio_dev*)this->private;
22 struct kvm_coalesced_mmio_zone *zone;
23 int next;
24 int i;
25
26 if (!is_write)
27 return 0;
28
29 /* kvm->lock is taken by the caller and must be not released before
30 * dev.read/write
31 */
32
33 /* Are we able to batch it ? */
34
35 /* last is the first free entry
36 * check if we don't meet the first used entry
37 * there is always one unused entry in the buffer
38 */
39
40 next = (dev->kvm->coalesced_mmio_ring->last + 1) %
41 KVM_COALESCED_MMIO_MAX;
42 if (next == dev->kvm->coalesced_mmio_ring->first) {
43 /* full */
44 return 0;
45 }
46
47 /* is it in a batchable area ? */
48
49 for (i = 0; i < dev->nb_zones; i++) {
50 zone = &dev->zone[i];
51
52 /* (addr,len) is fully included in
53 * (zone->addr, zone->size)
54 */
55
56 if (zone->addr <= addr &&
57 addr + len <= zone->addr + zone->size)
58 return 1;
59 }
60 return 0;
61}
62
63static void coalesced_mmio_write(struct kvm_io_device *this,
64 gpa_t addr, int len, const void *val)
65{
66 struct kvm_coalesced_mmio_dev *dev =
67 (struct kvm_coalesced_mmio_dev*)this->private;
68 struct kvm_coalesced_mmio_ring *ring = dev->kvm->coalesced_mmio_ring;
69
70 /* kvm->lock must be taken by caller before call to in_range()*/
71
72 /* copy data in first free entry of the ring */
73
74 ring->coalesced_mmio[ring->last].phys_addr = addr;
75 ring->coalesced_mmio[ring->last].len = len;
76 memcpy(ring->coalesced_mmio[ring->last].data, val, len);
77 smp_wmb();
78 ring->last = (ring->last + 1) % KVM_COALESCED_MMIO_MAX;
79}
80
81static void coalesced_mmio_destructor(struct kvm_io_device *this)
82{
83 kfree(this);
84}
85
86int kvm_coalesced_mmio_init(struct kvm *kvm)
87{
88 struct kvm_coalesced_mmio_dev *dev;
89
90 dev = kzalloc(sizeof(struct kvm_coalesced_mmio_dev), GFP_KERNEL);
91 if (!dev)
92 return -ENOMEM;
93 dev->dev.write = coalesced_mmio_write;
94 dev->dev.in_range = coalesced_mmio_in_range;
95 dev->dev.destructor = coalesced_mmio_destructor;
96 dev->dev.private = dev;
97 dev->kvm = kvm;
98 kvm->coalesced_mmio_dev = dev;
99 kvm_io_bus_register_dev(&kvm->mmio_bus, &dev->dev);
100
101 return 0;
102}
103
104int kvm_vm_ioctl_register_coalesced_mmio(struct kvm *kvm,
105 struct kvm_coalesced_mmio_zone *zone)
106{
107 struct kvm_coalesced_mmio_dev *dev = kvm->coalesced_mmio_dev;
108
109 if (dev == NULL)
110 return -EINVAL;
111
112 mutex_lock(&kvm->lock);
113 if (dev->nb_zones >= KVM_COALESCED_MMIO_ZONE_MAX) {
114 mutex_unlock(&kvm->lock);
115 return -ENOBUFS;
116 }
117
118 dev->zone[dev->nb_zones] = *zone;
119 dev->nb_zones++;
120
121 mutex_unlock(&kvm->lock);
122 return 0;
123}
124
125int kvm_vm_ioctl_unregister_coalesced_mmio(struct kvm *kvm,
126 struct kvm_coalesced_mmio_zone *zone)
127{
128 int i;
129 struct kvm_coalesced_mmio_dev *dev = kvm->coalesced_mmio_dev;
130 struct kvm_coalesced_mmio_zone *z;
131
132 if (dev == NULL)
133 return -EINVAL;
134
135 mutex_lock(&kvm->lock);
136
137 i = dev->nb_zones;
138 while(i) {
139 z = &dev->zone[i - 1];
140
141 /* unregister all zones
142 * included in (zone->addr, zone->size)
143 */
144
145 if (zone->addr <= z->addr &&
146 z->addr + z->size <= zone->addr + zone->size) {
147 dev->nb_zones--;
148 *z = dev->zone[dev->nb_zones];
149 }
150 i--;
151 }
152
153 mutex_unlock(&kvm->lock);
154
155 return 0;
156}
diff --git a/virt/kvm/coalesced_mmio.h b/virt/kvm/coalesced_mmio.h
new file mode 100644
index 000000000000..5ac0ec628461
--- /dev/null
+++ b/virt/kvm/coalesced_mmio.h
@@ -0,0 +1,23 @@
1/*
2 * KVM coalesced MMIO
3 *
4 * Copyright (c) 2008 Bull S.A.S.
5 *
6 * Author: Laurent Vivier <Laurent.Vivier@bull.net>
7 *
8 */
9
10#define KVM_COALESCED_MMIO_ZONE_MAX 100
11
12struct kvm_coalesced_mmio_dev {
13 struct kvm_io_device dev;
14 struct kvm *kvm;
15 int nb_zones;
16 struct kvm_coalesced_mmio_zone zone[KVM_COALESCED_MMIO_ZONE_MAX];
17};
18
19int kvm_coalesced_mmio_init(struct kvm *kvm);
20int kvm_vm_ioctl_register_coalesced_mmio(struct kvm *kvm,
21 struct kvm_coalesced_mmio_zone *zone);
22int kvm_vm_ioctl_unregister_coalesced_mmio(struct kvm *kvm,
23 struct kvm_coalesced_mmio_zone *zone);
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 9330fad2b918..7d10dfa0d388 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -47,6 +47,10 @@
47#include <asm/uaccess.h> 47#include <asm/uaccess.h>
48#include <asm/pgtable.h> 48#include <asm/pgtable.h>
49 49
50#ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
51#include "coalesced_mmio.h"
52#endif
53
50MODULE_AUTHOR("Qumranet"); 54MODULE_AUTHOR("Qumranet");
51MODULE_LICENSE("GPL"); 55MODULE_LICENSE("GPL");
52 56
@@ -185,10 +189,23 @@ EXPORT_SYMBOL_GPL(kvm_vcpu_uninit);
185static struct kvm *kvm_create_vm(void) 189static struct kvm *kvm_create_vm(void)
186{ 190{
187 struct kvm *kvm = kvm_arch_create_vm(); 191 struct kvm *kvm = kvm_arch_create_vm();
192#ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
193 struct page *page;
194#endif
188 195
189 if (IS_ERR(kvm)) 196 if (IS_ERR(kvm))
190 goto out; 197 goto out;
191 198
199#ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
200 page = alloc_page(GFP_KERNEL | __GFP_ZERO);
201 if (!page) {
202 kfree(kvm);
203 return ERR_PTR(-ENOMEM);
204 }
205 kvm->coalesced_mmio_ring =
206 (struct kvm_coalesced_mmio_ring *)page_address(page);
207#endif
208
192 kvm->mm = current->mm; 209 kvm->mm = current->mm;
193 atomic_inc(&kvm->mm->mm_count); 210 atomic_inc(&kvm->mm->mm_count);
194 spin_lock_init(&kvm->mmu_lock); 211 spin_lock_init(&kvm->mmu_lock);
@@ -200,6 +217,9 @@ static struct kvm *kvm_create_vm(void)
200 spin_lock(&kvm_lock); 217 spin_lock(&kvm_lock);
201 list_add(&kvm->vm_list, &vm_list); 218 list_add(&kvm->vm_list, &vm_list);
202 spin_unlock(&kvm_lock); 219 spin_unlock(&kvm_lock);
220#ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
221 kvm_coalesced_mmio_init(kvm);
222#endif
203out: 223out:
204 return kvm; 224 return kvm;
205} 225}
@@ -242,6 +262,10 @@ static void kvm_destroy_vm(struct kvm *kvm)
242 spin_unlock(&kvm_lock); 262 spin_unlock(&kvm_lock);
243 kvm_io_bus_destroy(&kvm->pio_bus); 263 kvm_io_bus_destroy(&kvm->pio_bus);
244 kvm_io_bus_destroy(&kvm->mmio_bus); 264 kvm_io_bus_destroy(&kvm->mmio_bus);
265#ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
266 if (kvm->coalesced_mmio_ring != NULL)
267 free_page((unsigned long)kvm->coalesced_mmio_ring);
268#endif
245 kvm_arch_destroy_vm(kvm); 269 kvm_arch_destroy_vm(kvm);
246 mmdrop(mm); 270 mmdrop(mm);
247} 271}
@@ -826,6 +850,10 @@ static int kvm_vcpu_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
826 else if (vmf->pgoff == KVM_PIO_PAGE_OFFSET) 850 else if (vmf->pgoff == KVM_PIO_PAGE_OFFSET)
827 page = virt_to_page(vcpu->arch.pio_data); 851 page = virt_to_page(vcpu->arch.pio_data);
828#endif 852#endif
853#ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
854 else if (vmf->pgoff == KVM_COALESCED_MMIO_PAGE_OFFSET)
855 page = virt_to_page(vcpu->kvm->coalesced_mmio_ring);
856#endif
829 else 857 else
830 return VM_FAULT_SIGBUS; 858 return VM_FAULT_SIGBUS;
831 get_page(page); 859 get_page(page);
@@ -1148,6 +1176,32 @@ static long kvm_vm_ioctl(struct file *filp,
1148 goto out; 1176 goto out;
1149 break; 1177 break;
1150 } 1178 }
1179#ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
1180 case KVM_REGISTER_COALESCED_MMIO: {
1181 struct kvm_coalesced_mmio_zone zone;
1182 r = -EFAULT;
1183 if (copy_from_user(&zone, argp, sizeof zone))
1184 goto out;
1185 r = -ENXIO;
1186 r = kvm_vm_ioctl_register_coalesced_mmio(kvm, &zone);
1187 if (r)
1188 goto out;
1189 r = 0;
1190 break;
1191 }
1192 case KVM_UNREGISTER_COALESCED_MMIO: {
1193 struct kvm_coalesced_mmio_zone zone;
1194 r = -EFAULT;
1195 if (copy_from_user(&zone, argp, sizeof zone))
1196 goto out;
1197 r = -ENXIO;
1198 r = kvm_vm_ioctl_unregister_coalesced_mmio(kvm, &zone);
1199 if (r)
1200 goto out;
1201 r = 0;
1202 break;
1203 }
1204#endif
1151 default: 1205 default:
1152 r = kvm_arch_vm_ioctl(filp, ioctl, arg); 1206 r = kvm_arch_vm_ioctl(filp, ioctl, arg);
1153 } 1207 }
@@ -1232,6 +1286,9 @@ static long kvm_dev_ioctl(struct file *filp,
1232#ifdef CONFIG_X86 1286#ifdef CONFIG_X86
1233 r += PAGE_SIZE; /* pio data page */ 1287 r += PAGE_SIZE; /* pio data page */
1234#endif 1288#endif
1289#ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
1290 r += PAGE_SIZE; /* coalesced mmio ring page */
1291#endif
1235 break; 1292 break;
1236 case KVM_TRACE_ENABLE: 1293 case KVM_TRACE_ENABLE:
1237 case KVM_TRACE_PAUSE: 1294 case KVM_TRACE_PAUSE:
generated by cgit v1.2.2 (git 2.25.0) at 2024-11-13 18:54:49 -0500