mm, dax, gpu: convert vm_insert_mixed to pfn_t

Convert the raw unsigned long 'pfn' argument to pfn_t for the purpose of
evaluating the PFN_MAP and PFN_DEV flags.  When both are set it triggers
_PAGE_DEVMAP to be set in the resulting pte.

There are no functional changes to the gpu drivers as a result of this
conversion.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave@sr71.net>
Cc: David Airlie <airlied@linux.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

10 files changed, 61 insertions, 14 deletions

diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h
index 4973cc9eacce..4c668f15a532 100644
--- a/arch/x86/include/asm/pgtable.h
+++ b/arch/x86/include/asm/pgtable.h
@@ -247,6 +247,11 @@ static inline pte_t pte_mkspecial(pte_t pte)
         return pte_set_flags(pte, _PAGE_SPECIAL);
 }
 
+static inline pte_t pte_mkdevmap(pte_t pte)
+{
+        return pte_set_flags(pte, _PAGE_SPECIAL|_PAGE_DEVMAP);
+}
+
 static inline pmd_t pmd_set_flags(pmd_t pmd, pmdval_t set)
 {
         pmdval_t v = native_pmd_val(pmd);
diff --git a/drivers/gpu/drm/exynos/exynos_drm_gem.c b/drivers/gpu/drm/exynos/exynos_drm_gem.c
index 252eb301470c..32358c5e3db4 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_gem.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_gem.c
@@ -14,6 +14,7 @@
 
 #include <linux/shmem_fs.h>
 #include <linux/dma-buf.h>
+#include <linux/pfn_t.h>
 #include <drm/exynos_drm.h>
 
 #include "exynos_drm_drv.h"
@@ -490,7 +491,8 @@ int exynos_drm_gem_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
         }
 
         pfn = page_to_pfn(exynos_gem->pages[page_offset]);
-        ret = vm_insert_mixed(vma, (unsigned long)vmf->virtual_address, pfn);
+        ret = vm_insert_mixed(vma, (unsigned long)vmf->virtual_address,
+                        __pfn_to_pfn_t(pfn, PFN_DEV));
 
 out:
         switch (ret) {
diff --git a/drivers/gpu/drm/gma500/framebuffer.c b/drivers/gpu/drm/gma500/framebuffer.c
index 2eaf1b31c7bd..72bc979fa0dc 100644
--- a/drivers/gpu/drm/gma500/framebuffer.c
+++ b/drivers/gpu/drm/gma500/framebuffer.c
@@ -21,6 +21,7 @@
 #include <linux/kernel.h>
 #include <linux/errno.h>
 #include <linux/string.h>
+#include <linux/pfn_t.h>
 #include <linux/mm.h>
 #include <linux/tty.h>
 #include <linux/slab.h>
@@ -132,7 +133,8 @@ static int psbfb_vm_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
         for (i = 0; i < page_num; i++) {
                 pfn = (phys_addr >> PAGE_SHIFT);
 
-                ret = vm_insert_mixed(vma, address, pfn);
+                ret = vm_insert_mixed(vma, address,
+                                __pfn_to_pfn_t(pfn, PFN_DEV));
                 if (unlikely((ret == -EBUSY) || (ret != 0 && i > 0)))
                         break;
                 else if (unlikely(ret != 0)) {
diff --git a/drivers/gpu/drm/msm/msm_gem.c b/drivers/gpu/drm/msm/msm_gem.c
index c76cc853b08a..3cedb8d5c855 100644
--- a/drivers/gpu/drm/msm/msm_gem.c
+++ b/drivers/gpu/drm/msm/msm_gem.c
@@ -18,6 +18,7 @@
 #include <linux/spinlock.h>
 #include <linux/shmem_fs.h>
 #include <linux/dma-buf.h>
+#include <linux/pfn_t.h>
 
 #include "msm_drv.h"
 #include "msm_gem.h"
@@ -222,7 +223,8 @@ int msm_gem_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
         VERB("Inserting %p pfn %lx, pa %lx", vmf->virtual_address,
                         pfn, pfn << PAGE_SHIFT);
 
-        ret = vm_insert_mixed(vma, (unsigned long)vmf->virtual_address, pfn);
+        ret = vm_insert_mixed(vma, (unsigned long)vmf->virtual_address,
+                        __pfn_to_pfn_t(pfn, PFN_DEV));
 
 out_unlock:
         mutex_unlock(&dev->struct_mutex);
diff --git a/drivers/gpu/drm/omapdrm/omap_gem.c b/drivers/gpu/drm/omapdrm/omap_gem.c
index 7ed08fdc4c42..ceba5459ceb7 100644
--- a/drivers/gpu/drm/omapdrm/omap_gem.c
+++ b/drivers/gpu/drm/omapdrm/omap_gem.c
@@ -19,6 +19,7 @@
 
 #include <linux/shmem_fs.h>
 #include <linux/spinlock.h>
+#include <linux/pfn_t.h>
 
 #include <drm/drm_vma_manager.h>
 
@@ -385,7 +386,8 @@ static int fault_1d(struct drm_gem_object *obj,
         VERB("Inserting %p pfn %lx, pa %lx", vmf->virtual_address,
                         pfn, pfn << PAGE_SHIFT);
 
-        return vm_insert_mixed(vma, (unsigned long)vmf->virtual_address, pfn);
+        return vm_insert_mixed(vma, (unsigned long)vmf->virtual_address,
+                        __pfn_to_pfn_t(pfn, PFN_DEV));
 }
 
 /* Special handling for the case of faulting in 2d tiled buffers */
@@ -478,7 +480,8 @@ static int fault_2d(struct drm_gem_object *obj,
                         pfn, pfn << PAGE_SHIFT);
 
         for (i = n; i > 0; i--) {
-                vm_insert_mixed(vma, (unsigned long)vaddr, pfn);
+                vm_insert_mixed(vma, (unsigned long)vaddr,
+                                __pfn_to_pfn_t(pfn, PFN_DEV));
                 pfn += usergart[fmt].stride_pfn;
                 vaddr += PAGE_SIZE * m;
         }
diff --git a/drivers/gpu/drm/ttm/ttm_bo_vm.c b/drivers/gpu/drm/ttm/ttm_bo_vm.c
index 8fb7213277cc..06d26dc438b2 100644
--- a/drivers/gpu/drm/ttm/ttm_bo_vm.c
+++ b/drivers/gpu/drm/ttm/ttm_bo_vm.c
@@ -35,6 +35,7 @@
 #include <ttm/ttm_placement.h>
 #include <drm/drm_vma_manager.h>
 #include <linux/mm.h>
+#include <linux/pfn_t.h>
 #include <linux/rbtree.h>
 #include <linux/module.h>
 #include <linux/uaccess.h>
@@ -229,7 +230,8 @@ static int ttm_bo_vm_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
                 }
 
                 if (vma->vm_flags & VM_MIXEDMAP)
-                        ret = vm_insert_mixed(&cvma, address, pfn);
+                        ret = vm_insert_mixed(&cvma, address,
+                                        __pfn_to_pfn_t(pfn, PFN_DEV));
                 else
                         ret = vm_insert_pfn(&cvma, address, pfn);
 
diff --git a/fs/dax.c b/fs/dax.c
index 6b13d6cd9a9a..574763eed8a3 100644
--- a/fs/dax.c
+++ b/fs/dax.c
@@ -363,7 +363,7 @@ static int dax_insert_mapping(struct inode *inode, struct buffer_head *bh,
         }
         dax_unmap_atomic(bdev, &dax);
 
-        error = vm_insert_mixed(vma, vaddr, pfn_t_to_pfn(dax.pfn));
+        error = vm_insert_mixed(vma, vaddr, dax.pfn);
 
  out:
         i_mmap_unlock_read(mapping);
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 8bb0907a3603..a9902152449f 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -2107,7 +2107,7 @@ int vm_insert_page(struct vm_area_struct *, unsigned long addr, struct page *);
 int vm_insert_pfn(struct vm_area_struct *vma, unsigned long addr,
                         unsigned long pfn);
 int vm_insert_mixed(struct vm_area_struct *vma, unsigned long addr,
-                        unsigned long pfn);
+                        pfn_t pfn);
 int vm_iomap_memory(struct vm_area_struct *vma, phys_addr_t start, unsigned long len);
 
 
diff --git a/include/linux/pfn_t.h b/include/linux/pfn_t.h
index c557a0e0b20c..bdaa275d7623 100644
--- a/include/linux/pfn_t.h
+++ b/include/linux/pfn_t.h
@@ -64,4 +64,31 @@ static inline pfn_t page_to_pfn_t(struct page *page)
 {
         return pfn_to_pfn_t(page_to_pfn(page));
 }
+
+static inline int pfn_t_valid(pfn_t pfn)
+{
+        return pfn_valid(pfn_t_to_pfn(pfn));
+}
+
+#ifdef CONFIG_MMU
+static inline pte_t pfn_t_pte(pfn_t pfn, pgprot_t pgprot)
+{
+        return pfn_pte(pfn_t_to_pfn(pfn), pgprot);
+}
+#endif
+
+#ifdef __HAVE_ARCH_PTE_DEVMAP
+static inline bool pfn_t_devmap(pfn_t pfn)
+{
+        const unsigned long flags = PFN_DEV|PFN_MAP;
+
+        return (pfn.val & flags) == flags;
+}
+#else
+static inline bool pfn_t_devmap(pfn_t pfn)
+{
+        return false;
+}
+pte_t pte_mkdevmap(pte_t pte);
+#endif
 #endif /* _LINUX_PFN_T_H_ */
diff --git a/mm/memory.c b/mm/memory.c
index 5a73c6ed8e5c..7f03652723ea 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -50,6 +50,7 @@
 #include <linux/export.h>
 #include <linux/delayacct.h>
 #include <linux/init.h>
+#include <linux/pfn_t.h>
 #include <linux/writeback.h>
 #include <linux/memcontrol.h>
 #include <linux/mmu_notifier.h>
@@ -1500,7 +1501,7 @@ int vm_insert_page(struct vm_area_struct *vma, unsigned long addr,
 EXPORT_SYMBOL(vm_insert_page);
 
 static int insert_pfn(struct vm_area_struct *vma, unsigned long addr,
-                        unsigned long pfn, pgprot_t prot)
+                        pfn_t pfn, pgprot_t prot)
 {
         struct mm_struct *mm = vma->vm_mm;
         int retval;
@@ -1516,7 +1517,10 @@ static int insert_pfn(struct vm_area_struct *vma, unsigned long addr,
                 goto out_unlock;
 
         /* Ok, finally just insert the thing.. */
-        entry = pte_mkspecial(pfn_pte(pfn, prot));
+        if (pfn_t_devmap(pfn))
+                entry = pte_mkdevmap(pfn_t_pte(pfn, prot));
+        else
+                entry = pte_mkspecial(pfn_t_pte(pfn, prot));
         set_pte_at(mm, addr, pte, entry);
         update_mmu_cache(vma, addr, pte); /* XXX: why not for insert_page? */
 
@@ -1566,14 +1570,14 @@ int vm_insert_pfn(struct vm_area_struct *vma, unsigned long addr,
         if (track_pfn_insert(vma, &pgprot, pfn))
                 return -EINVAL;
 
-        ret = insert_pfn(vma, addr, pfn, pgprot);
+        ret = insert_pfn(vma, addr, __pfn_to_pfn_t(pfn, PFN_DEV), pgprot);
 
         return ret;
 }
 EXPORT_SYMBOL(vm_insert_pfn);
 
 int vm_insert_mixed(struct vm_area_struct *vma, unsigned long addr,
-                        unsigned long pfn)
+                        pfn_t pfn)
 {
         BUG_ON(!(vma->vm_flags & VM_MIXEDMAP));
 
@@ -1587,10 +1591,10 @@ int vm_insert_mixed(struct vm_area_struct *vma, unsigned long addr,
          * than insert_pfn).  If a zero_pfn were inserted into a VM_MIXEDMAP
          * without pte special, it would there be refcounted as a normal page.
          */
-        if (!HAVE_PTE_SPECIAL && pfn_valid(pfn)) {
+        if (!HAVE_PTE_SPECIAL && pfn_t_valid(pfn)) {
                 struct page *page;
 
-                page = pfn_to_page(pfn);
+                page = pfn_t_to_page(pfn);
                 return insert_page(vma, addr, page, vma->vm_page_prot);
         }
         return insert_pfn(vma, addr, pfn, vma->vm_page_prot);