1 files changed, 32 insertions, 157 deletions

diff --git a/arch/x86/mm/pat.c b/arch/x86/mm/pat.c
index c009a241d562..e6718bb28065 100644
--- a/arch/x86/mm/pat.c
+++ b/arch/x86/mm/pat.c
@@ -182,10 +182,10 @@ static unsigned long pat_x_mtrr_type(u64 start, u64 end, unsigned long req_type)
                 u8 mtrr_type;
 
                 mtrr_type = mtrr_type_lookup(start, end);
-                if (mtrr_type == MTRR_TYPE_UNCACHABLE)
-                        return _PAGE_CACHE_UC;
-                if (mtrr_type == MTRR_TYPE_WRCOMB)
-                        return _PAGE_CACHE_WC;
+                if (mtrr_type != MTRR_TYPE_WRBACK)
+                        return _PAGE_CACHE_UC_MINUS;
+
+                return _PAGE_CACHE_WB;
         }
 
         return req_type;
@@ -352,23 +352,13 @@ int reserve_memtype(u64 start, u64 end, unsigned long req_type,
                 return 0;
         }
 
-        if (req_type == -1) {
-                /*
-                 * Call mtrr_lookup to get the type hint. This is an
-                 * optimization for /dev/mem mmap'ers into WB memory (BIOS
-                 * tools and ACPI tools). Use WB request for WB memory and use
-                 * UC_MINUS otherwise.
-                 */
-                u8 mtrr_type = mtrr_type_lookup(start, end);
-
-                if (mtrr_type == MTRR_TYPE_WRBACK)
-                        actual_type = _PAGE_CACHE_WB;
-                else
-                        actual_type = _PAGE_CACHE_UC_MINUS;
-        } else {
-                actual_type = pat_x_mtrr_type(start, end,
-                                              req_type & _PAGE_CACHE_MASK);
-        }
+        /*
+         * Call mtrr_lookup to get the type hint. This is an
+         * optimization for /dev/mem mmap'ers into WB memory (BIOS
+         * tools and ACPI tools). Use WB request for WB memory and use
+         * UC_MINUS otherwise.
+         */
+        actual_type = pat_x_mtrr_type(start, end, req_type & _PAGE_CACHE_MASK);
 
         if (new_type)
                 *new_type = actual_type;
@@ -546,9 +536,7 @@ static inline int range_is_allowed(unsigned long pfn, unsigned long size)
 int phys_mem_access_prot_allowed(struct file *file, unsigned long pfn,
                                 unsigned long size, pgprot_t *vma_prot)
 {
-        u64 offset = ((u64) pfn) << PAGE_SHIFT;
-        unsigned long flags = -1;
-        int retval;
+        unsigned long flags = _PAGE_CACHE_WB;
 
         if (!range_is_allowed(pfn, size))
                 return 0;
@@ -576,64 +564,11 @@ int phys_mem_access_prot_allowed(struct file *file, unsigned long pfn,
         }
 #endif
 
-        /*
-         * With O_SYNC, we can only take UC_MINUS mapping. Fail if we cannot.
-         *
-         * Without O_SYNC, we want to get
-         * - WB for WB-able memory and no other conflicting mappings
-         * - UC_MINUS for non-WB-able memory with no other conflicting mappings
-         * - Inherit from confliting mappings otherwise
-         */
-        if (flags != -1) {
-                retval = reserve_memtype(offset, offset + size, flags, NULL);
-        } else {
-                retval = reserve_memtype(offset, offset + size, -1, &flags);
-        }
-
-        if (retval < 0)
-                return 0;
-
-        if (((pfn < max_low_pfn_mapped) ||
-             (pfn >= (1UL<<(32 - PAGE_SHIFT)) && pfn < max_pfn_mapped)) &&
-            ioremap_change_attr((unsigned long)__va(offset), size, flags) < 0) {
-                free_memtype(offset, offset + size);
-                printk(KERN_INFO
-                "%s:%d /dev/mem ioremap_change_attr failed %s for %Lx-%Lx\n",
-                        current->comm, current->pid,
-                        cattr_name(flags),
-                        offset, (unsigned long long)(offset + size));
-                return 0;
-        }
-
         *vma_prot = __pgprot((pgprot_val(*vma_prot) & ~_PAGE_CACHE_MASK) |
                              flags);
         return 1;
 }
 
-void map_devmem(unsigned long pfn, unsigned long size, pgprot_t vma_prot)
-{
-        unsigned long want_flags = (pgprot_val(vma_prot) & _PAGE_CACHE_MASK);
-        u64 addr = (u64)pfn << PAGE_SHIFT;
-        unsigned long flags;
-
-        reserve_memtype(addr, addr + size, want_flags, &flags);
-        if (flags != want_flags) {
-                printk(KERN_INFO
-                "%s:%d /dev/mem expected mapping type %s for %Lx-%Lx, got %s\n",
-                        current->comm, current->pid,
-                        cattr_name(want_flags),
-                        addr, (unsigned long long)(addr + size),
-                        cattr_name(flags));
-        }
-}
-
-void unmap_devmem(unsigned long pfn, unsigned long size, pgprot_t vma_prot)
-{
-        u64 addr = (u64)pfn << PAGE_SHIFT;
-
-        free_memtype(addr, addr + size);
-}
-
 /*
  * Change the memory type for the physial address range in kernel identity
  * mapping space if that range is a part of identity map.
@@ -671,8 +606,8 @@ static int reserve_pfn_range(u64 paddr, unsigned long size, pgprot_t *vma_prot,
 {
         int is_ram = 0;
         int ret;
-        unsigned long flags;
         unsigned long want_flags = (pgprot_val(*vma_prot) & _PAGE_CACHE_MASK);
+        unsigned long flags = want_flags;
 
         is_ram = pat_pagerange_is_ram(paddr, paddr + size);
 
@@ -734,29 +669,28 @@ static void free_pfn_range(u64 paddr, unsigned long size)
  *
  * If the vma has a linear pfn mapping for the entire range, we get the prot
  * from pte and reserve the entire vma range with single reserve_pfn_range call.
- * Otherwise, we reserve the entire vma range, my ging through the PTEs page
- * by page to get physical address and protection.
  */
 int track_pfn_vma_copy(struct vm_area_struct *vma)
 {
-        int retval = 0;
-        unsigned long i, j;
         resource_size_t paddr;
         unsigned long prot;
-        unsigned long vma_start = vma->vm_start;
-        unsigned long vma_end = vma->vm_end;
-        unsigned long vma_size = vma_end - vma_start;
+        unsigned long vma_size = vma->vm_end - vma->vm_start;
         pgprot_t pgprot;
 
         if (!pat_enabled)
                 return 0;
 
+        /*
+         * For now, only handle remap_pfn_range() vmas where
+         * is_linear_pfn_mapping() == TRUE. Handling of
+         * vm_insert_pfn() is TBD.
+         */
         if (is_linear_pfn_mapping(vma)) {
                 /*
                  * reserve the whole chunk covered by vma. We need the
                  * starting address and protection from pte.
                  */
-                if (follow_phys(vma, vma_start, 0, &prot, &paddr)) {
+                if (follow_phys(vma, vma->vm_start, 0, &prot, &paddr)) {
                         WARN_ON_ONCE(1);
                         return -EINVAL;
                 }
@@ -764,28 +698,7 @@ int track_pfn_vma_copy(struct vm_area_struct *vma)
                 return reserve_pfn_range(paddr, vma_size, &pgprot, 1);
         }
 
-        /* reserve entire vma page by page, using pfn and prot from pte */
-        for (i = 0; i < vma_size; i += PAGE_SIZE) {
-                if (follow_phys(vma, vma_start + i, 0, &prot, &paddr))
-                        continue;
-
-                pgprot = __pgprot(prot);
-                retval = reserve_pfn_range(paddr, PAGE_SIZE, &pgprot, 1);
-                if (retval)
-                        goto cleanup_ret;
-        }
         return 0;
-
-cleanup_ret:
-        /* Reserve error: Cleanup partial reservation and return error */
-        for (j = 0; j < i; j += PAGE_SIZE) {
-                if (follow_phys(vma, vma_start + j, 0, &prot, &paddr))
-                        continue;
-
-                free_pfn_range(paddr, PAGE_SIZE);
-        }
-
-        return retval;
 }
 
 /*
@@ -795,50 +708,28 @@ cleanup_ret:
  * prot is passed in as a parameter for the new mapping. If the vma has a
  * linear pfn mapping for the entire range reserve the entire vma range with
  * single reserve_pfn_range call.
- * Otherwise, we look t the pfn and size and reserve only the specified range
- * page by page.
- *
- * Note that this function can be called with caller trying to map only a
- * subrange/page inside the vma.
  */
 int track_pfn_vma_new(struct vm_area_struct *vma, pgprot_t *prot,
                         unsigned long pfn, unsigned long size)
 {
-        int retval = 0;
-        unsigned long i, j;
-        resource_size_t base_paddr;
         resource_size_t paddr;
-        unsigned long vma_start = vma->vm_start;
-        unsigned long vma_end = vma->vm_end;
-        unsigned long vma_size = vma_end - vma_start;
+        unsigned long vma_size = vma->vm_end - vma->vm_start;
 
         if (!pat_enabled)
                 return 0;
 
+        /*
+         * For now, only handle remap_pfn_range() vmas where
+         * is_linear_pfn_mapping() == TRUE. Handling of
+         * vm_insert_pfn() is TBD.
+         */
         if (is_linear_pfn_mapping(vma)) {
                 /* reserve the whole chunk starting from vm_pgoff */
                 paddr = (resource_size_t)vma->vm_pgoff << PAGE_SHIFT;
                 return reserve_pfn_range(paddr, vma_size, prot, 0);
         }
 
-        /* reserve page by page using pfn and size */
-        base_paddr = (resource_size_t)pfn << PAGE_SHIFT;
-        for (i = 0; i < size; i += PAGE_SIZE) {
-                paddr = base_paddr + i;
-                retval = reserve_pfn_range(paddr, PAGE_SIZE, prot, 0);
-                if (retval)
-                        goto cleanup_ret;
-        }
         return 0;
-
-cleanup_ret:
-        /* Reserve error: Cleanup partial reservation and return error */
-        for (j = 0; j < i; j += PAGE_SIZE) {
-                paddr = base_paddr + j;
-                free_pfn_range(paddr, PAGE_SIZE);
-        }
-
-        return retval;
 }
 
 /*
@@ -849,39 +740,23 @@ cleanup_ret:
 void untrack_pfn_vma(struct vm_area_struct *vma, unsigned long pfn,
                         unsigned long size)
 {
-        unsigned long i;
         resource_size_t paddr;
-        unsigned long prot;
-        unsigned long vma_start = vma->vm_start;
-        unsigned long vma_end = vma->vm_end;
-        unsigned long vma_size = vma_end - vma_start;
+        unsigned long vma_size = vma->vm_end - vma->vm_start;
 
         if (!pat_enabled)
                 return;
 
+        /*
+         * For now, only handle remap_pfn_range() vmas where
+         * is_linear_pfn_mapping() == TRUE. Handling of
+         * vm_insert_pfn() is TBD.
+         */
         if (is_linear_pfn_mapping(vma)) {
                 /* free the whole chunk starting from vm_pgoff */
                 paddr = (resource_size_t)vma->vm_pgoff << PAGE_SHIFT;
                 free_pfn_range(paddr, vma_size);
                 return;
         }
-
-        if (size != 0 && size != vma_size) {
-                /* free page by page, using pfn and size */
-                paddr = (resource_size_t)pfn << PAGE_SHIFT;
-                for (i = 0; i < size; i += PAGE_SIZE) {
-                        paddr = paddr + i;
-                        free_pfn_range(paddr, PAGE_SIZE);
-                }
-        } else {
-                /* free entire vma, page by page, using the pfn from pte */
-                for (i = 0; i < vma_size; i += PAGE_SIZE) {
-                        if (follow_phys(vma, vma_start + i, 0, &prot, &paddr))
-                                continue;
-
-                        free_pfn_range(paddr, PAGE_SIZE);
-                }
-        }
 }
 
 pgprot_t pgprot_writecombine(pgprot_t prot)