From: Borislav Petkov b...@suse.de
Add the ability to map pages in an arbitrary pgd.
Signed-off-by: Borislav Petkov b...@suse.de
---
arch/x86/include/asm/pgtable_types.h | 3 +-
arch/x86/mm/pageattr.c | 80
2 files changed, 65 insertions(+), 18 deletions(-)
diff --git a/arch/x86/include/asm/pgtable_types.h
b/arch/x86/include/asm/pgtable_types.h
index e6423002c10b..0613e147f083 100644
--- a/arch/x86/include/asm/pgtable_types.h
+++ b/arch/x86/include/asm/pgtable_types.h
@@ -352,7 +352,8 @@ static inline void update_page_count(int level, unsigned
long pages) { }
*/
extern pte_t *lookup_address(unsigned long address, unsigned int *level);
extern phys_addr_t slow_virt_to_phys(void *__address);
-
+extern void kernel_map_pages_in_pgd(pgd_t *pgd, unsigned long address,
+ unsigned numpages, unsigned long
page_flags);
#endif /* !__ASSEMBLY__ */
#endif /* _ASM_X86_PGTABLE_DEFS_H */
diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c
index bb32480c2d71..3d64e5fc2adc 100644
--- a/arch/x86/mm/pageattr.c
+++ b/arch/x86/mm/pageattr.c
@@ -30,6 +30,7 @@
*/
struct cpa_data {
unsigned long *vaddr;
+ pgd_t *pgd;
pgprot_tmask_set;
pgprot_tmask_clr;
int numpages;
@@ -322,17 +323,9 @@ static inline pgprot_t static_protections(pgprot_t prot,
unsigned long address,
return prot;
}
-/*
- * Lookup the page table entry for a virtual address. Return a pointer
- * to the entry and the level of the mapping.
- *
- * Note: We return pud and pmd either when the entry is marked large
- * or when the present bit is not set. Otherwise we would return a
- * pointer to a nonexisting mapping.
- */
-pte_t *lookup_address(unsigned long address, unsigned int *level)
+static pte_t *
+__lookup_address_in_pgd(pgd_t *pgd, unsigned long address, unsigned int *level)
{
- pgd_t *pgd = pgd_offset_k(address);
pud_t *pud;
pmd_t *pmd;
@@ -361,8 +354,30 @@ pte_t *lookup_address(unsigned long address, unsigned int
*level)
return pte_offset_kernel(pmd, address);
}
+
+/*
+ * Lookup the page table entry for a virtual address. Return a pointer
+ * to the entry and the level of the mapping.
+ *
+ * Note: We return pud and pmd either when the entry is marked large
+ * or when the present bit is not set. Otherwise we would return a
+ * pointer to a nonexisting mapping.
+ */
+pte_t *lookup_address(unsigned long address, unsigned int *level)
+{
+ return __lookup_address_in_pgd(pgd_offset_k(address), address, level);
+}
EXPORT_SYMBOL_GPL(lookup_address);
+pte_t *_lookup_address_cpa(struct cpa_data *cpa, unsigned long address,
+ unsigned int *level)
+{
+ if (cpa-pgd)
+ return __lookup_address_in_pgd(cpa-pgd, address, level);
+
+ return lookup_address(address, level);
+}
+
/*
* This is necessary because __pa() does not work on some
* kinds of memory, like vmalloc() or the alloc_remap()
@@ -437,7 +452,7 @@ try_preserve_large_page(pte_t *kpte, unsigned long address,
* Check for races, another CPU might have split this page
* up already:
*/
- tmp = lookup_address(address, level);
+ tmp = _lookup_address_cpa(cpa, address, level);
if (tmp != kpte)
goto out_unlock;
@@ -543,7 +558,8 @@ out_unlock:
}
static int
-__split_large_page(pte_t *kpte, unsigned long address, struct page *base)
+__split_large_page(struct cpa_data *cpa, pte_t *kpte, unsigned long address,
+ struct page *base)
{
pte_t *pbase = (pte_t *)page_address(base);
unsigned long pfn, pfninc = 1;
@@ -556,7 +572,7 @@ __split_large_page(pte_t *kpte, unsigned long address,
struct page *base)
* Check for races, another CPU might have split this page
* up for us already:
*/
- tmp = lookup_address(address, level);
+ tmp = _lookup_address_cpa(cpa, address, level);
if (tmp != kpte) {
spin_unlock(pgd_lock);
return 1;
@@ -632,7 +648,8 @@ __split_large_page(pte_t *kpte, unsigned long address,
struct page *base)
return 0;
}
-static int split_large_page(pte_t *kpte, unsigned long address)
+static int split_large_page(struct cpa_data *cpa, pte_t *kpte,
+ unsigned long address)
{
struct page *base;
@@ -644,7 +661,7 @@ static int split_large_page(pte_t *kpte, unsigned long
address)
if (!base)
return -ENOMEM;
- if (__split_large_page(kpte, address, base))
+ if (__split_large_page(cpa, kpte, address, base))
__free_page(base);
return 0;
@@ -697,7 +714,10 @@ static int __change_page_attr(struct cpa_data *cpa, int
primary)
else
address = *cpa-vaddr;
repeat:
- kpte = lookup_address(address, level);
+ if (cpa-pgd)
+
