4 * Copyright (c) 2008 Bull S.A.S.
6 * Author: Laurent Vivier <Laurent.Vivier@bull.net>
12 #include <linux/kvm_host.h>
13 #include <linux/kvm.h>
15 #include "coalesced_mmio.h"
17 static int coalesced_mmio_in_range(struct kvm_io_device *this,
18 gpa_t addr, int len, int is_write)
20 struct kvm_coalesced_mmio_dev *dev =
21 (struct kvm_coalesced_mmio_dev*)this->private;
22 struct kvm_coalesced_mmio_zone *zone;
29 /* kvm->lock is taken by the caller and must be not released before
33 /* Are we able to batch it ? */
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
40 next = (dev->kvm->coalesced_mmio_ring->last + 1) %
41 KVM_COALESCED_MMIO_MAX;
42 if (next == dev->kvm->coalesced_mmio_ring->first) {
47 /* is it in a batchable area ? */
49 for (i = 0; i < dev->nb_zones; i++) {
52 /* (addr,len) is fully included in
53 * (zone->addr, zone->size)
56 if (zone->addr <= addr &&
57 addr + len <= zone->addr + zone->size)
63 static void coalesced_mmio_write(struct kvm_io_device *this,
64 gpa_t addr, int len, const void *val)
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;
70 /* kvm->lock must be taken by caller before call to in_range()*/
72 /* copy data in first free entry of the ring */
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);
78 ring->last = (ring->last + 1) % KVM_COALESCED_MMIO_MAX;
81 static void coalesced_mmio_destructor(struct kvm_io_device *this)
83 struct kvm_coalesced_mmio_dev *dev =
84 (struct kvm_coalesced_mmio_dev *)this->private;
89 int kvm_coalesced_mmio_init(struct kvm *kvm)
91 struct kvm_coalesced_mmio_dev *dev;
93 dev = kzalloc(sizeof(struct kvm_coalesced_mmio_dev), GFP_KERNEL);
96 dev->dev.write = coalesced_mmio_write;
97 dev->dev.in_range = coalesced_mmio_in_range;
98 dev->dev.destructor = coalesced_mmio_destructor;
99 dev->dev.private = dev;
101 kvm->coalesced_mmio_dev = dev;
102 kvm_io_bus_register_dev(&kvm->mmio_bus, &dev->dev);
107 int kvm_vm_ioctl_register_coalesced_mmio(struct kvm *kvm,
108 struct kvm_coalesced_mmio_zone *zone)
110 struct kvm_coalesced_mmio_dev *dev = kvm->coalesced_mmio_dev;
115 mutex_lock(&kvm->lock);
116 if (dev->nb_zones >= KVM_COALESCED_MMIO_ZONE_MAX) {
117 mutex_unlock(&kvm->lock);
121 dev->zone[dev->nb_zones] = *zone;
124 mutex_unlock(&kvm->lock);
128 int kvm_vm_ioctl_unregister_coalesced_mmio(struct kvm *kvm,
129 struct kvm_coalesced_mmio_zone *zone)
132 struct kvm_coalesced_mmio_dev *dev = kvm->coalesced_mmio_dev;
133 struct kvm_coalesced_mmio_zone *z;
138 mutex_lock(&kvm->lock);
142 z = &dev->zone[i - 1];
144 /* unregister all zones
145 * included in (zone->addr, zone->size)
148 if (zone->addr <= z->addr &&
149 z->addr + z->size <= zone->addr + zone->size) {
151 *z = dev->zone[dev->nb_zones];
156 mutex_unlock(&kvm->lock);