x86/amd-iommu: Add core functions for pd allocation/freeing
This patch factors some code of protection domain allocation
into seperate functions. This way the logic can be used to
allocate the passthrough domain later. As a side effect this
patch fixes an unlikely domain id leakage bug.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
diff --git a/arch/x86/kernel/amd_iommu.c b/arch/x86/kernel/amd_iommu.c
index 6c99f50..0934348 100644
--- a/arch/x86/kernel/amd_iommu.c
+++ b/arch/x86/kernel/amd_iommu.c
@@ -1988,19 +1988,47 @@
write_unlock_irqrestore(&amd_iommu_devtable_lock, flags);
}
-static int amd_iommu_domain_init(struct iommu_domain *dom)
+static void protection_domain_free(struct protection_domain *domain)
+{
+ if (!domain)
+ return;
+
+ if (domain->id)
+ domain_id_free(domain->id);
+
+ kfree(domain);
+}
+
+static struct protection_domain *protection_domain_alloc(void)
{
struct protection_domain *domain;
domain = kzalloc(sizeof(*domain), GFP_KERNEL);
if (!domain)
- return -ENOMEM;
+ return NULL;
spin_lock_init(&domain->lock);
- domain->mode = PAGE_MODE_3_LEVEL;
domain->id = domain_id_alloc();
if (!domain->id)
+ goto out_err;
+
+ return domain;
+
+out_err:
+ kfree(domain);
+
+ return NULL;
+}
+
+static int amd_iommu_domain_init(struct iommu_domain *dom)
+{
+ struct protection_domain *domain;
+
+ domain = protection_domain_alloc();
+ if (!domain)
goto out_free;
+
+ domain->mode = PAGE_MODE_3_LEVEL;
domain->pt_root = (void *)get_zeroed_page(GFP_KERNEL);
if (!domain->pt_root)
goto out_free;
@@ -2010,7 +2038,7 @@
return 0;
out_free:
- kfree(domain);
+ protection_domain_free(domain);
return -ENOMEM;
}