x86: PAT: modify follow_phys to return phys_addr prot and return value

[mirror_ubuntu-zesty-kernel.git] / include / linux / mm.h

diff --git a/include/linux/mm.h b/include/linux/mm.h
index ffee2f74341856275ead62f71c6093c8de457199..2f6e2f886d4bf196bcefbaf97298681ab8949b30 100644 (file)
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -145,6 +145,29 @@ extern pgprot_t protection_map[16];
 #define FAULT_FLAG_WRITE       0x01    /* Fault was a write access */
 #define FAULT_FLAG_NONLINEAR   0x02    /* Fault was via a nonlinear mapping */
 
+/*
+ * This interface is used by x86 PAT code to identify a pfn mapping that is
+ * linear over entire vma. This is to optimize PAT code that deals with
+ * marking the physical region with a particular prot. This is not for generic
+ * mm use. Note also that this check will not work if the pfn mapping is
+ * linear for a vma starting at physical address 0. In which case PAT code
+ * falls back to slow path of reserving physical range page by page.
+ */
+static inline int is_linear_pfn_mapping(struct vm_area_struct *vma)
+{
+       return ((vma->vm_flags & VM_PFNMAP) && vma->vm_pgoff);
+}
+
+static inline int is_pfn_mapping(struct vm_area_struct *vma)
+{
+       return (vma->vm_flags & VM_PFNMAP);
+}
+
+extern int track_pfn_vma_new(struct vm_area_struct *vma, pgprot_t prot,
+                               unsigned long pfn, unsigned long size);
+extern int track_pfn_vma_copy(struct vm_area_struct *vma);
+extern void untrack_pfn_vma(struct vm_area_struct *vma, unsigned long pfn,
+                               unsigned long size);
 
 /*
  * vm_fault is filled by the the pagefault handler and passed to the vma's
@@ -781,6 +804,8 @@ int copy_page_range(struct mm_struct *dst, struct mm_struct *src,
                        struct vm_area_struct *vma);
 void unmap_mapping_range(struct address_space *mapping,
                loff_t const holebegin, loff_t const holelen, int even_cows);
+int follow_phys(struct vm_area_struct *vma, unsigned long address,
+               unsigned int flags, unsigned long *prot, resource_size_t *phys);
 int generic_access_phys(struct vm_area_struct *vma, unsigned long addr,
                        void *buf, int len, int write);
 
@@ -1214,6 +1239,9 @@ struct page *follow_page(struct vm_area_struct *, unsigned long address,
 #define FOLL_GET       0x04    /* do get_page on page */
 #define FOLL_ANON      0x08    /* give ZERO_PAGE if no pgtable */
 
+int follow_pfnmap_pte(struct vm_area_struct *vma,
+                               unsigned long address, pte_t *ret_ptep);
+
 typedef int (*pte_fn_t)(pte_t *pte, pgtable_t token, unsigned long addr,
                        void *data);
 extern int apply_to_page_range(struct mm_struct *mm, unsigned long address,