This patch consolidates almost the same code used in iova_insert_rbtree()
and __alloc_and_insert_iova_range() functions. While touching this code,
replace BUG() with WARN_ON(1) to avoid taking down the whole system in
case of corrupted iova tree or incorrect calls.
Signed-off-by: Marek Szyprowski <m.szyprow...@samsung.com>
---
v2:
- replaced BUG() with WARN_ON(1) as suggested by Robin Murphy
v1:
- initial version
---
drivers/iommu/iova.c | 87 ++++++++++++++++++++--------------------------------
1 file changed, 33 insertions(+), 54 deletions(-)
diff --git a/drivers/iommu/iova.c b/drivers/iommu/iova.c
index b7268a14184f..e80a4105ac2a 100644
--- a/drivers/iommu/iova.c
+++ b/drivers/iommu/iova.c
@@ -100,6 +100,34 @@ static unsigned long iova_rcache_get(struct iova_domain
*iovad,
}
}
+/* Insert the iova into domain rbtree by holding writer lock */
+static void
+iova_insert_rbtree(struct rb_root *root, struct iova *iova,
+ struct rb_node *start)
+{
+ struct rb_node **new, *parent = NULL;
+
+ new = (start) ? &start : &(root->rb_node);
+ /* Figure out where to put new node */
+ while (*new) {
+ struct iova *this = rb_entry(*new, struct iova, node);
+
+ parent = *new;
+
+ if (iova->pfn_lo < this->pfn_lo)
+ new = &((*new)->rb_left);
+ else if (iova->pfn_lo > this->pfn_lo)
+ new = &((*new)->rb_right);
+ else {
+ WARN_ON(1); /* this should not happen */
+ return;
+ }
+ }
+ /* Add new node and rebalance tree. */
+ rb_link_node(&iova->node, parent, new);
+ rb_insert_color(&iova->node, root);
+}
+
/*
* Computes the padding size required, to make the start address
* naturally aligned on the power-of-two order of its size
@@ -157,35 +185,8 @@ static int __alloc_and_insert_iova_range(struct
iova_domain *iovad,
new->pfn_lo = limit_pfn - (size + pad_size) + 1;
new->pfn_hi = new->pfn_lo + size - 1;
- /* Insert the new_iova into domain rbtree by holding writer lock */
- /* Add new node and rebalance tree. */
- {
- struct rb_node **entry, *parent = NULL;
-
- /* If we have 'prev', it's a valid place to start the
- insertion. Otherwise, start from the root. */
- if (prev)
- entry = &prev;
- else
- entry = &iovad->rbroot.rb_node;
-
- /* Figure out where to put new node */
- while (*entry) {
- struct iova *this = rb_entry(*entry, struct iova, node);
- parent = *entry;
-
- if (new->pfn_lo < this->pfn_lo)
- entry = &((*entry)->rb_left);
- else if (new->pfn_lo > this->pfn_lo)
- entry = &((*entry)->rb_right);
- else
- BUG(); /* this should not happen */
- }
-
- /* Add new node and rebalance tree. */
- rb_link_node(&new->node, parent, entry);
- rb_insert_color(&new->node, &iovad->rbroot);
- }
+ /* If we have 'prev', it's a valid place to start the insertion. */
+ iova_insert_rbtree(&iovad->rbroot, new, prev);
__cached_rbnode_insert_update(iovad, saved_pfn, new);
spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
@@ -194,28 +195,6 @@ static int __alloc_and_insert_iova_range(struct
iova_domain *iovad,
return 0;
}
-static void
-iova_insert_rbtree(struct rb_root *root, struct iova *iova)
-{
- struct rb_node **new = &(root->rb_node), *parent = NULL;
- /* Figure out where to put new node */
- while (*new) {
- struct iova *this = rb_entry(*new, struct iova, node);
-
- parent = *new;
-
- if (iova->pfn_lo < this->pfn_lo)
- new = &((*new)->rb_left);
- else if (iova->pfn_lo > this->pfn_lo)
- new = &((*new)->rb_right);
- else
- BUG(); /* this should not happen */
- }
- /* Add new node and rebalance tree. */
- rb_link_node(&iova->node, parent, new);
- rb_insert_color(&iova->node, root);
-}
-
static struct kmem_cache *iova_cache;
static unsigned int iova_cache_users;
static DEFINE_MUTEX(iova_cache_mutex);
@@ -505,7 +484,7 @@ void put_iova_domain(struct iova_domain *iovad)
iova = alloc_and_init_iova(pfn_lo, pfn_hi);
if (iova)
- iova_insert_rbtree(&iovad->rbroot, iova);
+ iova_insert_rbtree(&iovad->rbroot, iova, NULL);
return iova;
}
@@ -612,11 +591,11 @@ struct iova *
rb_erase(&iova->node, &iovad->rbroot);
if (prev) {
- iova_insert_rbtree(&iovad->rbroot, prev);
+ iova_insert_rbtree(&iovad->rbroot, prev, NULL);
iova->pfn_lo = pfn_lo;
}
if (next) {
- iova_insert_rbtree(&iovad->rbroot, next);
+ iova_insert_rbtree(&iovad->rbroot, next, NULL);
iova->pfn_hi = pfn_hi;
}
spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
--
1.9.1
