intel-iommu: Remove superfluous iova_alloc_lock from IOVA code
We only ever obtain this lock immediately before the iova_rbtree_lock,
and release it immediately after the iova_rbtree_lock. So ditch it and
just use iova_rbtree_lock.
[v2: Remove the lockdep bits this time too]
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
diff --git a/drivers/pci/intel-iommu.c b/drivers/pci/intel-iommu.c
index c5f7c73..d6a8573 100644
--- a/drivers/pci/intel-iommu.c
+++ b/drivers/pci/intel-iommu.c
@@ -1309,7 +1309,6 @@
}
static struct iova_domain reserved_iova_list;
-static struct lock_class_key reserved_alloc_key;
static struct lock_class_key reserved_rbtree_key;
static void dmar_init_reserved_ranges(void)
@@ -1320,8 +1319,6 @@
init_iova_domain(&reserved_iova_list, DMA_32BIT_PFN);
- lockdep_set_class(&reserved_iova_list.iova_alloc_lock,
- &reserved_alloc_key);
lockdep_set_class(&reserved_iova_list.iova_rbtree_lock,
&reserved_rbtree_key);
diff --git a/drivers/pci/iova.c b/drivers/pci/iova.c
index 46dd440..7914951 100644
--- a/drivers/pci/iova.c
+++ b/drivers/pci/iova.c
@@ -22,7 +22,6 @@
void
init_iova_domain(struct iova_domain *iovad, unsigned long pfn_32bit)
{
- spin_lock_init(&iovad->iova_alloc_lock);
spin_lock_init(&iovad->iova_rbtree_lock);
iovad->rbroot = RB_ROOT;
iovad->cached32_node = NULL;
@@ -205,7 +204,6 @@
unsigned long limit_pfn,
bool size_aligned)
{
- unsigned long flags;
struct iova *new_iova;
int ret;
@@ -219,11 +217,9 @@
if (size_aligned)
size = __roundup_pow_of_two(size);
- spin_lock_irqsave(&iovad->iova_alloc_lock, flags);
ret = __alloc_and_insert_iova_range(iovad, size, limit_pfn,
new_iova, size_aligned);
- spin_unlock_irqrestore(&iovad->iova_alloc_lock, flags);
if (ret) {
free_iova_mem(new_iova);
return NULL;
@@ -381,8 +377,7 @@
struct iova *iova;
unsigned int overlap = 0;
- spin_lock_irqsave(&iovad->iova_alloc_lock, flags);
- spin_lock(&iovad->iova_rbtree_lock);
+ spin_lock_irqsave(&iovad->iova_rbtree_lock, flags);
for (node = rb_first(&iovad->rbroot); node; node = rb_next(node)) {
if (__is_range_overlap(node, pfn_lo, pfn_hi)) {
iova = container_of(node, struct iova, node);
@@ -402,8 +397,7 @@
iova = __insert_new_range(iovad, pfn_lo, pfn_hi);
finish:
- spin_unlock(&iovad->iova_rbtree_lock);
- spin_unlock_irqrestore(&iovad->iova_alloc_lock, flags);
+ spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
return iova;
}
@@ -420,8 +414,7 @@
unsigned long flags;
struct rb_node *node;
- spin_lock_irqsave(&from->iova_alloc_lock, flags);
- spin_lock(&from->iova_rbtree_lock);
+ spin_lock_irqsave(&from->iova_rbtree_lock, flags);
for (node = rb_first(&from->rbroot); node; node = rb_next(node)) {
struct iova *iova = container_of(node, struct iova, node);
struct iova *new_iova;
@@ -430,6 +423,5 @@
printk(KERN_ERR "Reserve iova range %lx@%lx failed\n",
iova->pfn_lo, iova->pfn_lo);
}
- spin_unlock(&from->iova_rbtree_lock);
- spin_unlock_irqrestore(&from->iova_alloc_lock, flags);
+ spin_unlock_irqrestore(&from->iova_rbtree_lock, flags);
}
diff --git a/include/linux/iova.h b/include/linux/iova.h
index 228f6c9..76a0759 100644
--- a/include/linux/iova.h
+++ b/include/linux/iova.h
@@ -28,7 +28,6 @@
/* holds all the iova translations for a domain */
struct iova_domain {
- spinlock_t iova_alloc_lock;/* Lock to protect iova allocation */
spinlock_t iova_rbtree_lock; /* Lock to protect update of rbtree */
struct rb_root rbroot; /* iova domain rbtree root */
struct rb_node *cached32_node; /* Save last alloced node */