From 3d39cecc4841e8d4c4abdb401d10180f5faaded0 Mon Sep 17 00:00:00 2001
From: David Woodhouse <David.Woodhouse@intel.com>
Date: Wed, 8 Jul 2009 15:23:30 +0100
Subject: [PATCH] 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>
---
drivers/pci/intel-iommu.c | 3 ---
drivers/pci/iova.c | 16 ++++------------
include/linux/iova.h | 1 -
3 files changed, 4 insertions(+), 16 deletions(-)
diff --git a/drivers/pci/intel-iommu.c b/drivers/pci/intel-iommu.c
index c5f7c73cbb55..d6a857397ec3 100644
--- a/drivers/pci/intel-iommu.c
+++ b/drivers/pci/intel-iommu.c
@@ -1309,7 +1309,6 @@ static void iommu_detach_domain(struct dmar_domain *domain,
}
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 @@ static void dmar_init_reserved_ranges(void)
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 46dd440e2315..7914951ef29a 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 @@ alloc_iova(struct iova_domain *iovad, unsigned long size,
unsigned long limit_pfn,
bool size_aligned)
{
- unsigned long flags;
struct iova *new_iova;
int ret;
@@ -219,11 +217,9 @@ alloc_iova(struct iova_domain *iovad, unsigned long size,
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 @@ reserve_iova(struct iova_domain *iovad,
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 @@ reserve_iova(struct iova_domain *iovad,
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 @@ copy_reserved_iova(struct iova_domain *from, struct iova_domain *to)
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 @@ copy_reserved_iova(struct iova_domain *from, struct iova_domain *to)
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 228f6c94b69c..76a0759e88ec 100644
--- a/include/linux/iova.h
+++ b/include/linux/iova.h
@@ -28,7 +28,6 @@ struct iova {
/* 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 */
--
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