x86/paravirt: add pte_flags to just get pte flags

Add pte_flags() to extract the flags from a pte.  This is a special
case of pte_val() which is only guaranteed to return the pte's flags
correctly; the page number may be corrupted or missing.

The intent is to allow paravirt implementations to return pte flags
without having to do any translation of the page number (most notably,
Xen).

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

diff --git a/arch/x86/kernel/paravirt.c b/arch/x86/kernel/paravirt.c
index 74f0c5ea2a0388af848faa058804cd9df86f4391..c98d54688180474ed0930c10fdc40444f1de9fca 100644 (file)
--- a/arch/x86/kernel/paravirt.c
+++ b/arch/x86/kernel/paravirt.c
@@ -403,6 +403,7 @@ struct pv_mmu_ops pv_mmu_ops = {
 #endif /* PAGETABLE_LEVELS >= 3 */
 
        .pte_val = native_pte_val,
+       .pte_flags = native_pte_val,
        .pgd_val = native_pgd_val,
 
        .make_pte = native_make_pte,

diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c
index 4a372b71239d6a368577a11caf283f26a37400f2..1b4b5fa498b3a611642b1bd1e766c16272692ec1 100644 (file)
--- a/arch/x86/xen/enlighten.c
+++ b/arch/x86/xen/enlighten.c
@@ -1101,6 +1101,7 @@ static const struct pv_mmu_ops xen_mmu_ops __initdata = {
        .set_pmd = xen_set_pmd,
 
        .pte_val = xen_pte_val,
+       .pte_flags = native_pte_val,
        .pgd_val = xen_pgd_val,
 
        .make_pte = xen_make_pte,

diff --git a/drivers/lguest/lg.h b/drivers/lguest/lg.h
index 005bd045d2ebca47a61a5633bfa171fe9df29896..5faefeaf679057b9c6b3e029dee4544343e5c132 100644 (file)
--- a/drivers/lguest/lg.h
+++ b/drivers/lguest/lg.h
@@ -136,7 +136,6 @@ int run_guest(struct lg_cpu *cpu, unsigned long __user *user);
  * first step in the migration to the kernel types.  pte_pfn is already defined
  * in the kernel. */
 #define pgd_flags(x)   (pgd_val(x) & ~PAGE_MASK)
-#define pte_flags(x)   (pte_val(x) & ~PAGE_MASK)
 #define pgd_pfn(x)     (pgd_val(x) >> PAGE_SHIFT)
 
 /* interrupts_and_traps.c: */

diff --git a/include/asm-x86/page.h b/include/asm-x86/page.h
index dc936dddf16118e667f7c074ef5f27fdbfd4dbf8..a1e2b9470f256c1f3da04a697bad458b81307f9c 100644 (file)
--- a/include/asm-x86/page.h
+++ b/include/asm-x86/page.h
@@ -160,6 +160,7 @@ static inline pteval_t native_pte_val(pte_t pte)
 #endif
 
 #define pte_val(x)     native_pte_val(x)
+#define pte_flags(x)   native_pte_val(x)
 #define __pte(x)       native_make_pte(x)
 
 #endif /* CONFIG_PARAVIRT */

diff --git a/include/asm-x86/paravirt.h b/include/asm-x86/paravirt.h
index 0f13b945e2400323cb65dfd6f8a7cc5b035c3319..5ea37a48eecbfbc96a8bf6c5a25c6f59a20e269d 100644 (file)
--- a/include/asm-x86/paravirt.h
+++ b/include/asm-x86/paravirt.h
@@ -239,6 +239,7 @@ struct pv_mmu_ops {
                                 unsigned long addr, pte_t *ptep);
 
        pteval_t (*pte_val)(pte_t);
+       pteval_t (*pte_flags)(pte_t);
        pte_t (*make_pte)(pteval_t pte);
 
        pgdval_t (*pgd_val)(pgd_t);
@@ -996,6 +997,20 @@ static inline pteval_t pte_val(pte_t pte)
        return ret;
 }
 
+static inline pteval_t pte_flags(pte_t pte)
+{
+       pteval_t ret;
+
+       if (sizeof(pteval_t) > sizeof(long))
+               ret = PVOP_CALL2(pteval_t, pv_mmu_ops.pte_flags,
+                                pte.pte, (u64)pte.pte >> 32);
+       else
+               ret = PVOP_CALL1(pteval_t, pv_mmu_ops.pte_flags,
+                                pte.pte);
+
+       return ret;
+}
+
 static inline pgd_t __pgd(pgdval_t val)
 {
        pgdval_t ret;

diff --git a/include/asm-x86/pgtable.h b/include/asm-x86/pgtable.h
index 97c271b2910b3266b4aaafa53385dfd8148bf374..47a852cb8c92875658a240349ff59808f653ce52 100644 (file)
--- a/include/asm-x86/pgtable.h
+++ b/include/asm-x86/pgtable.h
@@ -164,37 +164,37 @@ extern struct list_head pgd_list;
  */
 static inline int pte_dirty(pte_t pte)
 {
-       return pte_val(pte) & _PAGE_DIRTY;
+       return pte_flags(pte) & _PAGE_DIRTY;
 }
 
 static inline int pte_young(pte_t pte)
 {
-       return pte_val(pte) & _PAGE_ACCESSED;
+       return pte_flags(pte) & _PAGE_ACCESSED;
 }
 
 static inline int pte_write(pte_t pte)
 {
-       return pte_val(pte) & _PAGE_RW;
+       return pte_flags(pte) & _PAGE_RW;
 }
 
 static inline int pte_file(pte_t pte)
 {
-       return pte_val(pte) & _PAGE_FILE;
+       return pte_flags(pte) & _PAGE_FILE;
 }
 
 static inline int pte_huge(pte_t pte)
 {
-       return pte_val(pte) & _PAGE_PSE;
+       return pte_flags(pte) & _PAGE_PSE;
 }
 
 static inline int pte_global(pte_t pte)
 {
-       return pte_val(pte) & _PAGE_GLOBAL;
+       return pte_flags(pte) & _PAGE_GLOBAL;
 }
 
 static inline int pte_exec(pte_t pte)
 {
-       return !(pte_val(pte) & _PAGE_NX);
+       return !(pte_flags(pte) & _PAGE_NX);
 }
 
 static inline int pte_special(pte_t pte)
@@ -305,7 +305,7 @@ static inline pgprot_t pgprot_modify(pgprot_t oldprot, pgprot_t newprot)
        return __pgprot(preservebits | addbits);
 }
 
-#define pte_pgprot(x) __pgprot(pte_val(x) & ~PTE_MASK)
+#define pte_pgprot(x) __pgprot(pte_flags(x) & ~PTE_MASK)
 
 #define canon_pgprot(p) __pgprot(pgprot_val(p) & __supported_pte_mask)