From a13007160f1b9ec7c67e28ec9254f197c5c08d7d Mon Sep 17 00:00:00 2001 From: Amos Kong Date: Fri, 9 Mar 2012 12:17:32 +0800 Subject: KVM: resize kvm_io_range array dynamically This patch makes the kvm_io_range array can be resized dynamically. Signed-off-by: Amos Kong Signed-off-by: Marcelo Tosatti Signed-off-by: Avi Kivity --- virt/kvm/kvm_main.c | 38 ++++++++++++++++++-------------------- 1 file changed, 18 insertions(+), 20 deletions(-) (limited to 'virt/kvm') diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 42b73930a6d..a9565e24063 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -2393,9 +2393,6 @@ int kvm_io_bus_sort_cmp(const void *p1, const void *p2) int kvm_io_bus_insert_dev(struct kvm_io_bus *bus, struct kvm_io_device *dev, gpa_t addr, int len) { - if (bus->dev_count == NR_IOBUS_DEVS) - return -ENOSPC; - bus->range[bus->dev_count++] = (struct kvm_io_range) { .addr = addr, .len = len, @@ -2495,12 +2492,15 @@ int kvm_io_bus_register_dev(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr, struct kvm_io_bus *new_bus, *bus; bus = kvm->buses[bus_idx]; - if (bus->dev_count > NR_IOBUS_DEVS-1) + if (bus->dev_count > NR_IOBUS_DEVS - 1) return -ENOSPC; - new_bus = kmemdup(bus, sizeof(struct kvm_io_bus), GFP_KERNEL); + new_bus = kzalloc(sizeof(*bus) + ((bus->dev_count + 1) * + sizeof(struct kvm_io_range)), GFP_KERNEL); if (!new_bus) return -ENOMEM; + memcpy(new_bus, bus, sizeof(*bus) + (bus->dev_count * + sizeof(struct kvm_io_range))); kvm_io_bus_insert_dev(new_bus, dev, addr, len); rcu_assign_pointer(kvm->buses[bus_idx], new_bus); synchronize_srcu_expedited(&kvm->srcu); @@ -2517,27 +2517,25 @@ int kvm_io_bus_unregister_dev(struct kvm *kvm, enum kvm_bus bus_idx, struct kvm_io_bus *new_bus, *bus; bus = kvm->buses[bus_idx]; - - new_bus = kmemdup(bus, sizeof(*bus), GFP_KERNEL); - if (!new_bus) - return -ENOMEM; - r = -ENOENT; - for (i = 0; i < new_bus->dev_count; i++) - if (new_bus->range[i].dev == dev) { + for (i = 0; i < bus->dev_count; i++) + if (bus->range[i].dev == dev) { r = 0; - new_bus->dev_count--; - new_bus->range[i] = new_bus->range[new_bus->dev_count]; - sort(new_bus->range, new_bus->dev_count, - sizeof(struct kvm_io_range), - kvm_io_bus_sort_cmp, NULL); break; } - if (r) { - kfree(new_bus); + if (r) return r; - } + + new_bus = kzalloc(sizeof(*bus) + ((bus->dev_count - 1) * + sizeof(struct kvm_io_range)), GFP_KERNEL); + if (!new_bus) + return -ENOMEM; + + memcpy(new_bus, bus, sizeof(*bus) + i * sizeof(struct kvm_io_range)); + new_bus->dev_count--; + memcpy(new_bus->range + i, bus->range + i + 1, + (new_bus->dev_count - i) * sizeof(struct kvm_io_range)); rcu_assign_pointer(kvm->buses[bus_idx], new_bus); synchronize_srcu_expedited(&kvm->srcu); -- cgit v1.2.3-70-g09d2