The patch titled
GRU virtual -> physical translation
has been added to the -mm tree. Its filename is
gru-driver-v3-page-faults-exceptions-gru-virtual-physical-translation.patch
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See http://www.zip.com.au/~akpm/linux/patches/stuff/added-to-mm.txt to find
out what to do about this
The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/
------------------------------------------------------
Subject: GRU virtual -> physical translation
From: Jack Steiner <steiner@xxxxxxx>
Open code the equivalent to follow_page(). This eliminates the
requirement for an EXPORT of follow_page(). In addition, the code
is optimized for the specific case that is needed by the GRU and only
supports architectures supported by the GRU (ia64 & x86_64).
Signed-off-by: Jack Steiner <steiner@xxxxxxx>
Cc: Christoph Hellwig <hch@xxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
drivers/misc/sgi-gru/grufault.c | 54 +++++++++++++++++++++++++-----
1 file changed, 45 insertions(+), 9 deletions(-)
diff -puN drivers/misc/sgi-gru/grufault.c~gru-driver-v3-page-faults-exceptions-gru-virtual-physical-translation drivers/misc/sgi-gru/grufault.c
--- a/drivers/misc/sgi-gru/grufault.c~gru-driver-v3-page-faults-exceptions-gru-virtual-physical-translation
+++ a/drivers/misc/sgi-gru/grufault.c
@@ -213,20 +213,56 @@ static int non_atomic_pte_lookup(struct
return 0;
}
+/*
+ *
+ * atomic_pte_lookup
+ *
+ * Convert a user virtual address to a physical address
+ * Only supports Intel large pages (2MB only) on x86_64.
+ * ZZZ - hugepage support is incomplete
+ */
static int atomic_pte_lookup(struct vm_area_struct *vma, unsigned long vaddr,
- int write, unsigned long *paddr, int *pageshift)
+ int write, unsigned long *paddr, int *pageshift)
{
- struct page *page;
+ pgd_t *pgdp;
+ pmd_t *pmdp;
+ pud_t *pudp;
+ pte_t pte;
+
+ WARN_ON(irqs_disabled()); /* ZZZ debug */
+
+ local_irq_disable();
+ pgdp = pgd_offset(vma->vm_mm, vaddr);
+ if (unlikely(pgd_none(*pgdp)))
+ goto err;
+
+ pudp = pud_offset(pgdp, vaddr);
+ if (unlikely(pud_none(*pudp)))
+ goto err;
+
+ pmdp = pmd_offset(pudp, vaddr);
+ if (unlikely(pmd_none(*pmdp)))
+ goto err;
+#ifdef CONFIG_X86_64
+ if (unlikely(pmd_large(*pmdp)))
+ pte = *(pte_t *) pmdp;
+ else
+#endif
+ pte = *pte_offset_kernel(pmdp, vaddr);
- /* ZZZ Need to handle HUGE pages */
- if (is_vm_hugetlb_page(vma))
- return -EFAULT;
- *pageshift = PAGE_SHIFT;
- page = follow_page(vma, vaddr, (write ? FOLL_WRITE : 0));
- if (!page)
+ local_irq_enable();
+
+ if (unlikely(!pte_present(pte) ||
+ (write && (!pte_write(pte) || !pte_dirty(pte)))))
return 1;
- *paddr = page_to_phys(page);
+
+ *paddr = pte_pfn(pte) << PAGE_SHIFT;
+ *pageshift = is_vm_hugetlb_page(vma) ? HPAGE_SHIFT : PAGE_SHIFT;
return 0;
+
+err:
+ local_irq_enable();
+ return 1;
}
/*
_
Patches currently in -mm which might be from steiner@xxxxxxx are
linux-next.patch
mmu-notifiers-add-list_del_init_rcu.patch
mmu-notifiers-add-mm_take_all_locks-operation.patch
mmu-notifiers-add-mm_take_all_locks-operation-checkpatch-fixes.patch
mmu-notifier-core.patch
mmu-notifier-core-fix.patch
mmu-notifier-core-fix-2.patch
mm-add-zap_vma_ptes-a-library-function-to-unmap-driver-ptes.patch
gru-driver-v3-hardware-data-structures.patch
gru-driver-v3-gru-instructions-macros.patch
gru-driver-v3-driver-internal-header-files.patch
gru-driver-v3-kernel-services-header-files.patch
gru-driver-v3-driver-initialization-file-vma-ops.patch
gru-driver-v3-page-faults-exceptions.patch
gru-driver-v3-page-faults-exceptions-gru-virtual-physical-translation.patch
gru-driver-v3-kernel-services-provide-by-driver.patch
gru-driver-v3-resource-management.patch
gru-driver-v3-resource-management-unmap-driver-ptes-gru.patch
gru-driver-v3-proc-interfaces.patch
gru-driver-v3-tlb-flushing-mmuops-callouts.patch
gru-driver-v3-driver-makefile.patch
gru-driver-v3-export-is_uv_system-zap_page_range-follow_page.patch
gru-driver-v3-driver-misc-makefile-kconfig-changes.patch
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