From: Joerg Roedel <jroe...@suse.de>

Collect all pages that belong to a page-table in a list and
free them after the tree has been traversed. This allows to
implement safer page-table updates in subsequent patches.
Also move the functions for page-table freeing a bit upwards
in the file so that they are usable from the iommu_map() path.

Signed-off-by: Joerg Roedel <jroe...@suse.de>
---
 drivers/iommu/amd_iommu.c | 144 ++++++++++++++++++++++----------------
 1 file changed, 83 insertions(+), 61 deletions(-)

diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
index 1167ff0416cf..2655bd91af93 100644
--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -1317,6 +1317,89 @@ static void domain_flush_devices(struct 
protection_domain *domain)
  *
  ****************************************************************************/
 
+static void free_page_list(struct page *freelist)
+{
+       while (freelist != NULL) {
+               unsigned long p = (unsigned long)page_address(freelist);
+               freelist = freelist->freelist;
+               free_page(p);
+       }
+}
+
+static struct page *free_pt_page(unsigned long pt, struct page *freelist)
+{
+       struct page *p = virt_to_page((void *)pt);
+
+       p->freelist = freelist;
+
+       return p;
+}
+
+#define DEFINE_FREE_PT_FN(LVL, FN)                                             
\
+static struct page *free_pt_##LVL (unsigned long __pt, struct page *freelist)  
\
+{                                                                              
\
+       unsigned long p;                                                        
\
+       u64 *pt;                                                                
\
+       int i;                                                                  
\
+                                                                               
\
+       pt = (u64 *)__pt;                                                       
\
+                                                                               
\
+       for (i = 0; i < 512; ++i) {                                             
\
+               /* PTE present? */                                              
\
+               if (!IOMMU_PTE_PRESENT(pt[i]))                                  
\
+                       continue;                                               
\
+                                                                               
\
+               /* Large PTE? */                                                
\
+               if (PM_PTE_LEVEL(pt[i]) == 0 ||                                 
\
+                   PM_PTE_LEVEL(pt[i]) == 7)                                   
\
+                       continue;                                               
\
+                                                                               
\
+               p = (unsigned long)IOMMU_PTE_PAGE(pt[i]);                       
\
+               freelist = FN(p, freelist);                                     
\
+       }                                                                       
\
+                                                                               
\
+       return free_pt_page((unsigned long)pt, freelist);                       
\
+}
+
+DEFINE_FREE_PT_FN(l2, free_pt_page)
+DEFINE_FREE_PT_FN(l3, free_pt_l2)
+DEFINE_FREE_PT_FN(l4, free_pt_l3)
+DEFINE_FREE_PT_FN(l5, free_pt_l4)
+DEFINE_FREE_PT_FN(l6, free_pt_l5)
+
+static void free_pagetable(struct protection_domain *domain)
+{
+       unsigned long root = (unsigned long)domain->pt_root;
+       struct page *freelist = NULL;
+
+       switch (domain->mode) {
+       case PAGE_MODE_NONE:
+               break;
+       case PAGE_MODE_1_LEVEL:
+               freelist = free_pt_page(root, freelist);
+               break;
+       case PAGE_MODE_2_LEVEL:
+               freelist = free_pt_l2(root, freelist);
+               break;
+       case PAGE_MODE_3_LEVEL:
+               freelist = free_pt_l3(root, freelist);
+               break;
+       case PAGE_MODE_4_LEVEL:
+               freelist = free_pt_l4(root, freelist);
+               break;
+       case PAGE_MODE_5_LEVEL:
+               freelist = free_pt_l5(root, freelist);
+               break;
+       case PAGE_MODE_6_LEVEL:
+               freelist = free_pt_l6(root, freelist);
+               break;
+       default:
+               BUG();
+       }
+
+       free_page_list(freelist);
+}
+
 /*
  * This function is used to add another level to an IO page table. Adding
  * another level increases the size of the address space by 9 bits to a size up
@@ -1638,67 +1721,6 @@ static void domain_id_free(int id)
        spin_unlock(&pd_bitmap_lock);
 }
 
-#define DEFINE_FREE_PT_FN(LVL, FN)                             \
-static void free_pt_##LVL (unsigned long __pt)                 \
-{                                                              \
-       unsigned long p;                                        \
-       u64 *pt;                                                \
-       int i;                                                  \
-                                                               \
-       pt = (u64 *)__pt;                                       \
-                                                               \
-       for (i = 0; i < 512; ++i) {                             \
-               /* PTE present? */                              \
-               if (!IOMMU_PTE_PRESENT(pt[i]))                  \
-                       continue;                               \
-                                                               \
-               /* Large PTE? */                                \
-               if (PM_PTE_LEVEL(pt[i]) == 0 ||                 \
-                   PM_PTE_LEVEL(pt[i]) == 7)                   \
-                       continue;                               \
-                                                               \
-               p = (unsigned long)IOMMU_PTE_PAGE(pt[i]);       \
-               FN(p);                                          \
-       }                                                       \
-       free_page((unsigned long)pt);                           \
-}
-
-DEFINE_FREE_PT_FN(l2, free_page)
-DEFINE_FREE_PT_FN(l3, free_pt_l2)
-DEFINE_FREE_PT_FN(l4, free_pt_l3)
-DEFINE_FREE_PT_FN(l5, free_pt_l4)
-DEFINE_FREE_PT_FN(l6, free_pt_l5)
-
-static void free_pagetable(struct protection_domain *domain)
-{
-       unsigned long root = (unsigned long)domain->pt_root;
-
-       switch (domain->mode) {
-       case PAGE_MODE_NONE:
-               break;
-       case PAGE_MODE_1_LEVEL:
-               free_page(root);
-               break;
-       case PAGE_MODE_2_LEVEL:
-               free_pt_l2(root);
-               break;
-       case PAGE_MODE_3_LEVEL:
-               free_pt_l3(root);
-               break;
-       case PAGE_MODE_4_LEVEL:
-               free_pt_l4(root);
-               break;
-       case PAGE_MODE_5_LEVEL:
-               free_pt_l5(root);
-               break;
-       case PAGE_MODE_6_LEVEL:
-               free_pt_l6(root);
-               break;
-       default:
-               BUG();
-       }
-}
-
 static void free_gcr3_tbl_level1(u64 *tbl)
 {
        u64 *ptr;
-- 
2.17.1

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