arch/tile: allow building Linux with transparent huge pages enabled
The change adds some infrastructure for managing tile pmd's more generally,
using pte_pmd() and pmd_pte() methods to translate pmd values to and
from ptes, since on TILEPro a pmd is really just a nested structure
holding a pgd (aka pte). Several existing pmd methods are moved into
this framework, and a whole raft of additional pmd accessors are defined
that are used by the transparent hugepage framework.
The tile PTE now has a "client2" bit. The bit is used to indicate a
transparent huge page is in the process of being split into subpages.
This change also fixes a generic bug where the return value of the
generic pmdp_splitting_flush() was incorrect.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
diff --git a/arch/tile/include/asm/pgtable.h b/arch/tile/include/asm/pgtable.h
index 6749091..ec907d4 100644
--- a/arch/tile/include/asm/pgtable.h
+++ b/arch/tile/include/asm/pgtable.h
@@ -187,6 +187,7 @@
* Undefined behaviour if not..
*/
#define pte_present hv_pte_get_present
+#define pte_mknotpresent hv_pte_clear_present
#define pte_user hv_pte_get_user
#define pte_read hv_pte_get_readable
#define pte_dirty hv_pte_get_dirty
@@ -312,7 +313,7 @@
*/
static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
{
- return pfn_pte(hv_pte_get_pfn(pte), newprot);
+ return pfn_pte(pte_pfn(pte), newprot);
}
/*
@@ -410,6 +411,46 @@
return (address >> PMD_SHIFT) & (PTRS_PER_PMD - 1);
}
+#define __HAVE_ARCH_PMDP_TEST_AND_CLEAR_YOUNG
+static inline int pmdp_test_and_clear_young(struct vm_area_struct *vma,
+ unsigned long address,
+ pmd_t *pmdp)
+{
+ return ptep_test_and_clear_young(vma, address, pmdp_ptep(pmdp));
+}
+
+#define __HAVE_ARCH_PMDP_SET_WRPROTECT
+static inline void pmdp_set_wrprotect(struct mm_struct *mm,
+ unsigned long address, pmd_t *pmdp)
+{
+ ptep_set_wrprotect(mm, address, pmdp_ptep(pmdp));
+}
+
+
+#define __HAVE_ARCH_PMDP_GET_AND_CLEAR
+static inline pmd_t pmdp_get_and_clear(struct mm_struct *mm,
+ unsigned long address,
+ pmd_t *pmdp)
+{
+ return pte_pmd(ptep_get_and_clear(mm, address, pmdp_ptep(pmdp)));
+}
+
+static inline void __set_pmd(pmd_t *pmdp, pmd_t pmdval)
+{
+ set_pte(pmdp_ptep(pmdp), pmd_pte(pmdval));
+}
+
+#define set_pmd_at(mm, addr, pmdp, pmdval) __set_pmd(pmdp, pmdval)
+
+/* Create a pmd from a PTFN. */
+static inline pmd_t ptfn_pmd(unsigned long ptfn, pgprot_t prot)
+{
+ return pte_pmd(hv_pte_set_ptfn(prot, ptfn));
+}
+
+/* Return the page-table frame number (ptfn) that a pmd_t points at. */
+#define pmd_ptfn(pmd) hv_pte_get_ptfn(pmd_pte(pmd))
+
/*
* A given kernel pmd_t maps to a specific virtual address (either a
* kernel huge page or a kernel pte_t table). Since kernel pte_t
@@ -432,6 +473,47 @@
*/
#define pmd_page(pmd) pfn_to_page(HV_PTFN_TO_PFN(pmd_ptfn(pmd)))
+static inline void pmd_clear(pmd_t *pmdp)
+{
+ __pte_clear(pmdp_ptep(pmdp));
+}
+
+#define pmd_mknotpresent(pmd) pte_pmd(pte_mknotpresent(pmd_pte(pmd)))
+#define pmd_young(pmd) pte_young(pmd_pte(pmd))
+#define pmd_mkyoung(pmd) pte_pmd(pte_mkyoung(pmd_pte(pmd)))
+#define pmd_mkold(pmd) pte_pmd(pte_mkold(pmd_pte(pmd)))
+#define pmd_mkwrite(pmd) pte_pmd(pte_mkwrite(pmd_pte(pmd)))
+#define pmd_write(pmd) pte_write(pmd_pte(pmd))
+#define pmd_wrprotect(pmd) pte_pmd(pte_wrprotect(pmd_pte(pmd)))
+#define pmd_mkdirty(pmd) pte_pmd(pte_mkdirty(pmd_pte(pmd)))
+#define pmd_huge_page(pmd) pte_huge(pmd_pte(pmd))
+#define pmd_mkhuge(pmd) pte_pmd(pte_mkhuge(pmd_pte(pmd)))
+#define __HAVE_ARCH_PMD_WRITE
+
+#define pfn_pmd(pfn, pgprot) pte_pmd(pfn_pte((pfn), (pgprot)))
+#define pmd_pfn(pmd) pte_pfn(pmd_pte(pmd))
+#define mk_pmd(page, pgprot) pfn_pmd(page_to_pfn(page), (pgprot))
+
+static inline pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot)
+{
+ return pfn_pmd(pmd_pfn(pmd), newprot);
+}
+
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+#define has_transparent_hugepage() 1
+#define pmd_trans_huge pmd_huge_page
+
+static inline pmd_t pmd_mksplitting(pmd_t pmd)
+{
+ return pte_pmd(hv_pte_set_client2(pmd_pte(pmd)));
+}
+
+static inline int pmd_trans_splitting(pmd_t pmd)
+{
+ return hv_pte_get_client2(pmd_pte(pmd));
+}
+#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
+
/*
* The pte page can be thought of an array like this: pte_t[PTRS_PER_PTE]
*
@@ -448,11 +530,6 @@
return (pte_t *)pmd_page_vaddr(*pmd) + pte_index(address);
}
-static inline int pmd_huge_page(pmd_t pmd)
-{
- return pmd_val(pmd) & _PAGE_HUGE_PAGE;
-}
-
#include <asm-generic/pgtable.h>
/* Support /proc/NN/pgtable API. */
diff --git a/arch/tile/include/asm/pgtable_32.h b/arch/tile/include/asm/pgtable_32.h
index 9f98529..27e20f6 100644
--- a/arch/tile/include/asm/pgtable_32.h
+++ b/arch/tile/include/asm/pgtable_32.h
@@ -111,24 +111,14 @@
return pte;
}
-static inline void __set_pmd(pmd_t *pmdp, pmd_t pmdval)
-{
- set_pte(&pmdp->pud.pgd, pmdval.pud.pgd);
-}
-
-/* Create a pmd from a PTFN. */
-static inline pmd_t ptfn_pmd(unsigned long ptfn, pgprot_t prot)
-{
- return (pmd_t){ { hv_pte_set_ptfn(prot, ptfn) } };
-}
-
-/* Return the page-table frame number (ptfn) that a pmd_t points at. */
-#define pmd_ptfn(pmd) hv_pte_get_ptfn((pmd).pud.pgd)
-
-static inline void pmd_clear(pmd_t *pmdp)
-{
- __pte_clear(&pmdp->pud.pgd);
-}
+/*
+ * pmds are wrappers around pgds, which are the same as ptes.
+ * It's often convenient to "cast" back and forth and use the pte methods,
+ * which are the methods supplied by the hypervisor.
+ */
+#define pmd_pte(pmd) ((pmd).pud.pgd)
+#define pmdp_ptep(pmdp) (&(pmdp)->pud.pgd)
+#define pte_pmd(pte) ((pmd_t){ { (pte) } })
#endif /* __ASSEMBLY__ */
diff --git a/arch/tile/include/asm/pgtable_64.h b/arch/tile/include/asm/pgtable_64.h
index fd80328..e105f3a 100644
--- a/arch/tile/include/asm/pgtable_64.h
+++ b/arch/tile/include/asm/pgtable_64.h
@@ -108,28 +108,6 @@
#define pmd_offset(pud, address) \
((pmd_t *)pud_page_vaddr(*(pud)) + pmd_index(address))
-static inline void __set_pmd(pmd_t *pmdp, pmd_t pmdval)
-{
- set_pte(pmdp, pmdval);
-}
-
-/* Create a pmd from a PTFN and pgprot. */
-static inline pmd_t ptfn_pmd(unsigned long ptfn, pgprot_t prot)
-{
- return hv_pte_set_ptfn(prot, ptfn);
-}
-
-/* Return the page-table frame number (ptfn) that a pmd_t points at. */
-static inline unsigned long pmd_ptfn(pmd_t pmd)
-{
- return hv_pte_get_ptfn(pmd);
-}
-
-static inline void pmd_clear(pmd_t *pmdp)
-{
- __pte_clear(pmdp);
-}
-
/* Normalize an address to having the correct high bits set. */
#define pgd_addr_normalize pgd_addr_normalize
static inline unsigned long pgd_addr_normalize(unsigned long addr)
@@ -170,6 +148,13 @@
return hv_pte(__insn_exch(&ptep->val, 0UL));
}
+/*
+ * pmds are the same as pgds and ptes, so converting is a no-op.
+ */
+#define pmd_pte(pmd) (pmd)
+#define pmdp_ptep(pmdp) (pmdp)
+#define pte_pmd(pte) (pte)
+
#endif /* __ASSEMBLY__ */
#endif /* _ASM_TILE_PGTABLE_64_H */
diff --git a/arch/tile/include/hv/hypervisor.h b/arch/tile/include/hv/hypervisor.h
index 72ec1e9..793123e 100644
--- a/arch/tile/include/hv/hypervisor.h
+++ b/arch/tile/include/hv/hypervisor.h
@@ -1855,8 +1855,7 @@
future use. */
#define HV_PTE_INDEX_MODE 16 /**< Page mode; see HV_PTE_MODE_xxx */
#define HV_PTE_MODE_BITS 3 /**< Number of bits in mode */
- /* Bit 19 is reserved for
- future use. */
+#define HV_PTE_INDEX_CLIENT2 19 /**< Page client state 2 */
#define HV_PTE_INDEX_LOTAR 20 /**< Page's LOTAR; must be high bits
of word */
#define HV_PTE_LOTAR_BITS 12 /**< Number of bits in a LOTAR */
@@ -2046,6 +2045,13 @@
*/
#define HV_PTE_CLIENT1 (__HV_PTE_ONE << HV_PTE_INDEX_CLIENT1)
+/** Client-private bit in PTE.
+ *
+ * This bit is guaranteed not to be inspected or modified by the
+ * hypervisor.
+ */
+#define HV_PTE_CLIENT2 (__HV_PTE_ONE << HV_PTE_INDEX_CLIENT2)
+
/** Non-coherent (NC) bit in PTE.
*
* If this bit is set, the mapping that is set up will be non-coherent
@@ -2180,6 +2186,7 @@
_HV_BIT(page, PAGE)
_HV_BIT(client0, CLIENT0)
_HV_BIT(client1, CLIENT1)
+_HV_BIT(client2, CLIENT2)
_HV_BIT(migrating, MIGRATING)
_HV_BIT(nc, NC)
_HV_BIT(readable, READABLE)
diff --git a/include/asm-generic/pgtable.h b/include/asm-generic/pgtable.h
index 125c54e..e2768f1 100644
--- a/include/asm-generic/pgtable.h
+++ b/include/asm-generic/pgtable.h
@@ -158,9 +158,8 @@
#endif
#ifndef __HAVE_ARCH_PMDP_SPLITTING_FLUSH
-extern pmd_t pmdp_splitting_flush(struct vm_area_struct *vma,
- unsigned long address,
- pmd_t *pmdp);
+extern void pmdp_splitting_flush(struct vm_area_struct *vma,
+ unsigned long address, pmd_t *pmdp);
#endif
#ifndef __HAVE_ARCH_PTE_SAME
diff --git a/mm/pgtable-generic.c b/mm/pgtable-generic.c
index 5a74fea..74c0dda 100644
--- a/mm/pgtable-generic.c
+++ b/mm/pgtable-generic.c
@@ -109,8 +109,8 @@
#ifndef __HAVE_ARCH_PMDP_SPLITTING_FLUSH
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
-pmd_t pmdp_splitting_flush(struct vm_area_struct *vma, unsigned long address,
- pmd_t *pmdp)
+void pmdp_splitting_flush(struct vm_area_struct *vma, unsigned long address,
+ pmd_t *pmdp)
{
pmd_t pmd = pmd_mksplitting(*pmdp);
VM_BUG_ON(address & ~HPAGE_PMD_MASK);