iommu/iova: Consolidate code for adding new node to iovad domain rbtree

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.szyprowski@samsung.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
This commit is contained in:
Marek Szyprowski 2017-02-24 12:13:37 +01:00 committed by Joerg Roedel
parent 97da3854c5
commit d751751a9f
1 changed files with 33 additions and 54 deletions

View File

@ -100,6 +100,34 @@ __cached_rbnode_delete_update(struct iova_domain *iovad, struct iova *free)
}
}
/* 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 @@ __insert_new_range(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 @@ split_and_remove_iova(struct iova_domain *iovad, struct iova *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);