[PATCH 36/40] KVM: convert slots_lock to a mutex

From: Avi Kivity
Date: Wed Feb 10 2010 - 12:24:39 EST

From: Marcelo Tosatti <mtosatti@xxxxxxxxxx>

Signed-off-by: Marcelo Tosatti <mtosatti@xxxxxxxxxx>
---
arch/ia64/kvm/kvm-ia64.c | 4 ++--
arch/powerpc/kvm/book3s.c | 4 ++--
arch/x86/kvm/i8254.c | 2 +-
arch/x86/kvm/i8259.c | 4 ++--
arch/x86/kvm/vmx.c | 8 ++++----
arch/x86/kvm/x86.c | 16 ++++++++--------
include/linux/kvm_host.h | 2 +-
virt/kvm/coalesced_mmio.c | 14 +++++++-------
virt/kvm/eventfd.c | 10 +++++-----
virt/kvm/ioapic.c | 4 ++--
virt/kvm/kvm_main.c | 10 +++++-----
11 files changed, 39 insertions(+), 39 deletions(-)

diff --git a/arch/ia64/kvm/kvm-ia64.c b/arch/ia64/kvm/kvm-ia64.c
index d5e3846..e6ac549 100644
--- a/arch/ia64/kvm/kvm-ia64.c
+++ b/arch/ia64/kvm/kvm-ia64.c
@@ -1834,7 +1834,7 @@ int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm,
struct kvm_memory_slot *memslot;
int is_dirty = 0;

- down_write(&kvm->slots_lock);
+ mutex_lock(&kvm->slots_lock);
spin_lock(&kvm->arch.dirty_log_lock);

r = kvm_ia64_sync_dirty_log(kvm, log);
@@ -1854,7 +1854,7 @@ int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm,
}
r = 0;
out:
- up_write(&kvm->slots_lock);
+ mutex_unlock(&kvm->slots_lock);
spin_unlock(&kvm->arch.dirty_log_lock);
return r;
}
diff --git a/arch/powerpc/kvm/book3s.c b/arch/powerpc/kvm/book3s.c
index bb8873d..492dcc1 100644
--- a/arch/powerpc/kvm/book3s.c
+++ b/arch/powerpc/kvm/book3s.c
@@ -857,7 +857,7 @@ int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm,
int is_dirty = 0;
int r, n;

- down_write(&kvm->slots_lock);
+ mutex_lock(&kvm->slots_lock);

r = kvm_get_dirty_log(kvm, log, &is_dirty);
if (r)
@@ -879,7 +879,7 @@ int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm,

r = 0;
out:
- up_write(&kvm->slots_lock);
+ mutex_unlock(&kvm->slots_lock);
return r;
}

diff --git a/arch/x86/kvm/i8254.c b/arch/x86/kvm/i8254.c
index a7259e8..caad189 100644
--- a/arch/x86/kvm/i8254.c
+++ b/arch/x86/kvm/i8254.c
@@ -602,7 +602,7 @@ static const struct kvm_io_device_ops speaker_dev_ops = {
.write = speaker_ioport_write,
};

-/* Caller must have writers lock on slots_lock */
+/* Caller must hold slots_lock */
struct kvm_pit *kvm_create_pit(struct kvm *kvm, u32 flags)
{
struct kvm_pit *pit;
diff --git a/arch/x86/kvm/i8259.c b/arch/x86/kvm/i8259.c
index b7d145b..d5753a7 100644
--- a/arch/x86/kvm/i8259.c
+++ b/arch/x86/kvm/i8259.c
@@ -533,9 +533,9 @@ struct kvm_pic *kvm_create_pic(struct kvm *kvm)
* Initialize PIO device
*/
kvm_iodevice_init(&s->dev, &picdev_ops);
- down_write(&kvm->slots_lock);
+ mutex_lock(&kvm->slots_lock);
ret = kvm_io_bus_register_dev(kvm, KVM_PIO_BUS, &s->dev);
- up_write(&kvm->slots_lock);
+ mutex_unlock(&kvm->slots_lock);
if (ret < 0) {
kfree(s);
return NULL;
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 22ab713..f04e2ff 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -2223,7 +2223,7 @@ static int alloc_apic_access_page(struct kvm *kvm)
struct kvm_userspace_memory_region kvm_userspace_mem;
int r = 0;

- down_write(&kvm->slots_lock);
+ mutex_lock(&kvm->slots_lock);
if (kvm->arch.apic_access_page)
goto out;
kvm_userspace_mem.slot = APIC_ACCESS_PAGE_PRIVATE_MEMSLOT;
@@ -2236,7 +2236,7 @@ static int alloc_apic_access_page(struct kvm *kvm)

kvm->arch.apic_access_page = gfn_to_page(kvm, 0xfee00);
out:
- up_write(&kvm->slots_lock);
+ mutex_unlock(&kvm->slots_lock);
return r;
}

@@ -2245,7 +2245,7 @@ static int alloc_identity_pagetable(struct kvm *kvm)
struct kvm_userspace_memory_region kvm_userspace_mem;
int r = 0;

- down_write(&kvm->slots_lock);
+ mutex_lock(&kvm->slots_lock);
if (kvm->arch.ept_identity_pagetable)
goto out;
kvm_userspace_mem.slot = IDENTITY_PAGETABLE_PRIVATE_MEMSLOT;
@@ -2260,7 +2260,7 @@ static int alloc_identity_pagetable(struct kvm *kvm)
kvm->arch.ept_identity_pagetable = gfn_to_page(kvm,
kvm->arch.ept_identity_map_addr >> PAGE_SHIFT);
out:
- up_write(&kvm->slots_lock);
+ mutex_unlock(&kvm->slots_lock);
return r;
}

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 0cb795c..4b00831 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -2209,14 +2209,14 @@ static int kvm_vm_ioctl_set_nr_mmu_pages(struct kvm *kvm,
if (kvm_nr_mmu_pages < KVM_MIN_ALLOC_MMU_PAGES)
return -EINVAL;

- down_write(&kvm->slots_lock);
+ mutex_lock(&kvm->slots_lock);
spin_lock(&kvm->mmu_lock);

kvm_mmu_change_mmu_pages(kvm, kvm_nr_mmu_pages);
kvm->arch.n_requested_mmu_pages = kvm_nr_mmu_pages;

spin_unlock(&kvm->mmu_lock);
- up_write(&kvm->slots_lock);
+ mutex_unlock(&kvm->slots_lock);
return 0;
}

@@ -2293,7 +2293,7 @@ static int kvm_vm_ioctl_set_memory_alias(struct kvm *kvm,
if (!aliases)
goto out;

- down_write(&kvm->slots_lock);
+ mutex_lock(&kvm->slots_lock);

/* invalidate any gfn reference in case of deletion/shrinking */
memcpy(aliases, kvm->arch.aliases, sizeof(struct kvm_mem_aliases));
@@ -2329,7 +2329,7 @@ static int kvm_vm_ioctl_set_memory_alias(struct kvm *kvm,
r = 0;

out_unlock:
- up_write(&kvm->slots_lock);
+ mutex_unlock(&kvm->slots_lock);
out:
return r;
}
@@ -2463,7 +2463,7 @@ int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm,
unsigned long is_dirty = 0;
unsigned long *dirty_bitmap = NULL;

- down_write(&kvm->slots_lock);
+ mutex_lock(&kvm->slots_lock);

r = -EINVAL;
if (log->slot >= KVM_MEMORY_SLOTS)
@@ -2513,7 +2513,7 @@ int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm,
out_free:
vfree(dirty_bitmap);
out:
- up_write(&kvm->slots_lock);
+ mutex_unlock(&kvm->slots_lock);
return r;
}

@@ -2626,7 +2626,7 @@ long kvm_arch_vm_ioctl(struct file *filp,
sizeof(struct kvm_pit_config)))
goto out;
create_pit:
- down_write(&kvm->slots_lock);
+ mutex_lock(&kvm->slots_lock);
r = -EEXIST;
if (kvm->arch.vpit)
goto create_pit_unlock;
@@ -2635,7 +2635,7 @@ long kvm_arch_vm_ioctl(struct file *filp,
if (kvm->arch.vpit)
r = 0;
create_pit_unlock:
- up_write(&kvm->slots_lock);
+ mutex_unlock(&kvm->slots_lock);
break;
case KVM_IRQ_LINE_STATUS:
case KVM_IRQ_LINE: {
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 0bb9aa2..bb0314e 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -161,7 +161,7 @@ struct kvm_memslots {
struct kvm {
spinlock_t mmu_lock;
spinlock_t requests_lock;
- struct rw_semaphore slots_lock;
+ struct mutex slots_lock;
struct mm_struct *mm; /* userspace tied to this vm */
struct kvm_memslots *memslots;
struct srcu_struct srcu;
diff --git a/virt/kvm/coalesced_mmio.c b/virt/kvm/coalesced_mmio.c
index a736a93..5de6594 100644
--- a/virt/kvm/coalesced_mmio.c
+++ b/virt/kvm/coalesced_mmio.c
@@ -110,9 +110,9 @@ int kvm_coalesced_mmio_init(struct kvm *kvm)
dev->kvm = kvm;
kvm->coalesced_mmio_dev = dev;

- down_write(&kvm->slots_lock);
+ mutex_lock(&kvm->slots_lock);
ret = kvm_io_bus_register_dev(kvm, KVM_MMIO_BUS, &dev->dev);
- up_write(&kvm->slots_lock);
+ mutex_unlock(&kvm->slots_lock);
if (ret < 0)
goto out_free_dev;

@@ -140,16 +140,16 @@ int kvm_vm_ioctl_register_coalesced_mmio(struct kvm *kvm,
if (dev == NULL)
return -EINVAL;

- down_write(&kvm->slots_lock);
+ mutex_lock(&kvm->slots_lock);
if (dev->nb_zones >= KVM_COALESCED_MMIO_ZONE_MAX) {
- up_write(&kvm->slots_lock);
+ mutex_unlock(&kvm->slots_lock);
return -ENOBUFS;
}

dev->zone[dev->nb_zones] = *zone;
dev->nb_zones++;

- up_write(&kvm->slots_lock);
+ mutex_unlock(&kvm->slots_lock);
return 0;
}

@@ -163,7 +163,7 @@ int kvm_vm_ioctl_unregister_coalesced_mmio(struct kvm *kvm,
if (dev == NULL)
return -EINVAL;

- down_write(&kvm->slots_lock);
+ mutex_lock(&kvm->slots_lock);

i = dev->nb_zones;
while(i) {
@@ -181,7 +181,7 @@ int kvm_vm_ioctl_unregister_coalesced_mmio(struct kvm *kvm,
i--;
}

- up_write(&kvm->slots_lock);
+ mutex_unlock(&kvm->slots_lock);

return 0;
}
diff --git a/virt/kvm/eventfd.c b/virt/kvm/eventfd.c
index 315a586..486c604 100644
--- a/virt/kvm/eventfd.c
+++ b/virt/kvm/eventfd.c
@@ -508,7 +508,7 @@ kvm_assign_ioeventfd(struct kvm *kvm, struct kvm_ioeventfd *args)
else
p->wildcard = true;

- down_write(&kvm->slots_lock);
+ mutex_lock(&kvm->slots_lock);

/* Verify that there isnt a match already */
if (ioeventfd_check_collision(kvm, p)) {
@@ -524,12 +524,12 @@ kvm_assign_ioeventfd(struct kvm *kvm, struct kvm_ioeventfd *args)

list_add_tail(&p->list, &kvm->ioeventfds);

- up_write(&kvm->slots_lock);
+ mutex_unlock(&kvm->slots_lock);

return 0;

unlock_fail:
- up_write(&kvm->slots_lock);
+ mutex_unlock(&kvm->slots_lock);

fail:
kfree(p);
@@ -551,7 +551,7 @@ kvm_deassign_ioeventfd(struct kvm *kvm, struct kvm_ioeventfd *args)
if (IS_ERR(eventfd))
return PTR_ERR(eventfd);

- down_write(&kvm->slots_lock);
+ mutex_lock(&kvm->slots_lock);

list_for_each_entry_safe(p, tmp, &kvm->ioeventfds, list) {
bool wildcard = !(args->flags & KVM_IOEVENTFD_FLAG_DATAMATCH);
@@ -571,7 +571,7 @@ kvm_deassign_ioeventfd(struct kvm *kvm, struct kvm_ioeventfd *args)
break;
}

- up_write(&kvm->slots_lock);
+ mutex_unlock(&kvm->slots_lock);

eventfd_ctx_put(eventfd);

diff --git a/virt/kvm/ioapic.c b/virt/kvm/ioapic.c
index f326a6f..f01392f 100644
--- a/virt/kvm/ioapic.c
+++ b/virt/kvm/ioapic.c
@@ -372,9 +372,9 @@ int kvm_ioapic_init(struct kvm *kvm)
kvm_ioapic_reset(ioapic);
kvm_iodevice_init(&ioapic->dev, &ioapic_mmio_ops);
ioapic->kvm = kvm;
- down_write(&kvm->slots_lock);
+ mutex_lock(&kvm->slots_lock);
ret = kvm_io_bus_register_dev(kvm, KVM_MMIO_BUS, &ioapic->dev);
- up_write(&kvm->slots_lock);
+ mutex_unlock(&kvm->slots_lock);
if (ret < 0)
kfree(ioapic);

diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 659bc12..2b7cd6c 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -429,7 +429,7 @@ static struct kvm *kvm_create_vm(void)
kvm_eventfd_init(kvm);
mutex_init(&kvm->lock);
mutex_init(&kvm->irq_lock);
- init_rwsem(&kvm->slots_lock);
+ mutex_init(&kvm->slots_lock);
atomic_set(&kvm->users_count, 1);
spin_lock(&kvm_lock);
list_add(&kvm->vm_list, &vm_list);
@@ -763,9 +763,9 @@ int kvm_set_memory_region(struct kvm *kvm,
{
int r;

- down_write(&kvm->slots_lock);
+ mutex_lock(&kvm->slots_lock);
r = __kvm_set_memory_region(kvm, mem, user_alloc);
- up_write(&kvm->slots_lock);
+ mutex_unlock(&kvm->slots_lock);
return r;
}
EXPORT_SYMBOL_GPL(kvm_set_memory_region);
@@ -1997,7 +1997,7 @@ int kvm_io_bus_read(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr,
return -EOPNOTSUPP;
}

-/* Caller must have write lock on slots_lock. */
+/* Caller must hold slots_lock. */
int kvm_io_bus_register_dev(struct kvm *kvm, enum kvm_bus bus_idx,
struct kvm_io_device *dev)
{
@@ -2019,7 +2019,7 @@ int kvm_io_bus_register_dev(struct kvm *kvm, enum kvm_bus bus_idx,
return 0;
}

-/* Caller must have write lock on slots_lock. */
+/* Caller must hold slots_lock. */
int kvm_io_bus_unregister_dev(struct kvm *kvm, enum kvm_bus bus_idx,
struct kvm_io_device *dev)
{
--
1.6.5.3

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/