[PATCH 6/6] x86/xen: open code alloc_vm_area in arch_gnttab_valloc

[Christoph Hellwig <hch@xxxxxx>]

Open code alloc_vm_area in the last remaining caller.

Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
 arch/x86/xen/grant-table.c | 27 +++++++++++++++------
 include/linux/vmalloc.h    |  5 +---
 mm/nommu.c                 |  7 ------
 mm/vmalloc.c               | 48 --------------------------------------
 4 files changed, 21 insertions(+), 66 deletions(-)

diff --git a/arch/x86/xen/grant-table.c b/arch/x86/xen/grant-table.c
index 4988e19598c8a5..ccb377c07c651f 100644
--- a/arch/x86/xen/grant-table.c
+++ b/arch/x86/xen/grant-table.c
@@ -90,19 +90,32 @@ void arch_gnttab_unmap(void *shared, unsigned long 
nr_gframes)
        }
 }
 
+static int gnttab_apply(pte_t *pte, unsigned long addr, void *data)
+{
+       pte_t ***p = data;
+
+       **p = pte;
+       (*p)++;
+       return 0;
+}
+
 static int arch_gnttab_valloc(struct gnttab_vm_area *area, unsigned nr_frames)
 {
        area->ptes = kmalloc_array(nr_frames, sizeof(*area->ptes), GFP_KERNEL);
        if (area->ptes == NULL)
                return -ENOMEM;
-
-       area->area = alloc_vm_area(PAGE_SIZE * nr_frames, area->ptes);
-       if (area->area == NULL) {
-               kfree(area->ptes);
-               return -ENOMEM;
-       }
-
+       area->area = get_vm_area(PAGE_SIZE * nr_frames, VM_IOREMAP);
+       if (!area->area)
+               goto out_free_ptes;
+       if (apply_to_page_range(&init_mm, (unsigned long)area->area->addr,
+                       PAGE_SIZE * nr_frames, gnttab_apply, &area->ptes))
+               goto out_free_vm_area;
        return 0;
+out_free_vm_area:
+       free_vm_area(area->area);
+out_free_ptes:
+       kfree(area->ptes);
+       return -ENOMEM;
 }
 
 static void arch_gnttab_vfree(struct gnttab_vm_area *area)
diff --git a/include/linux/vmalloc.h b/include/linux/vmalloc.h
index 8ecd92a947ee0c..a1a4e2f8163504 100644
--- a/include/linux/vmalloc.h
+++ b/include/linux/vmalloc.h
@@ -168,6 +168,7 @@ extern struct vm_struct *__get_vm_area_caller(unsigned long 
size,
                                        unsigned long flags,
                                        unsigned long start, unsigned long end,
                                        const void *caller);
+void free_vm_area(struct vm_struct *area);
 extern struct vm_struct *remove_vm_area(const void *addr);
 extern struct vm_struct *find_vm_area(const void *addr);
 
@@ -203,10 +204,6 @@ static inline void set_vm_flush_reset_perms(void *addr)
 }
 #endif
 
-/* Allocate/destroy a 'vmalloc' VM area. */
-extern struct vm_struct *alloc_vm_area(size_t size, pte_t **ptes);
-extern void free_vm_area(struct vm_struct *area);
-
 /* for /dev/kmem */
 extern long vread(char *buf, char *addr, unsigned long count);
 extern long vwrite(char *buf, char *addr, unsigned long count);
diff --git a/mm/nommu.c b/mm/nommu.c
index 75a327149af127..9272f30e4c4726 100644
--- a/mm/nommu.c
+++ b/mm/nommu.c
@@ -354,13 +354,6 @@ void vm_unmap_aliases(void)
 }
 EXPORT_SYMBOL_GPL(vm_unmap_aliases);
 
-struct vm_struct *alloc_vm_area(size_t size, pte_t **ptes)
-{
-       BUG();
-       return NULL;
-}
-EXPORT_SYMBOL_GPL(alloc_vm_area);
-
 void free_vm_area(struct vm_struct *area)
 {
        BUG();
diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index 59f2afcf26c312..9f29147deca580 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -3077,54 +3077,6 @@ int remap_vmalloc_range(struct vm_area_struct *vma, void 
*addr,
 }
 EXPORT_SYMBOL(remap_vmalloc_range);
 
-static int f(pte_t *pte, unsigned long addr, void *data)
-{
-       pte_t ***p = data;
-
-       if (p) {
-               *(*p) = pte;
-               (*p)++;
-       }
-       return 0;
-}
-
-/**
- * alloc_vm_area - allocate a range of kernel address space
- * @size:         size of the area
- * @ptes:         returns the PTEs for the address space
- *
- * Returns:    NULL on failure, vm_struct on success
- *
- * This function reserves a range of kernel address space, and
- * allocates pagetables to map that range.  No actual mappings
- * are created.
- *
- * If @ptes is non-NULL, pointers to the PTEs (in init_mm)
- * allocated for the VM area are returned.
- */
-struct vm_struct *alloc_vm_area(size_t size, pte_t **ptes)
-{
-       struct vm_struct *area;
-
-       area = get_vm_area_caller(size, VM_IOREMAP,
-                               __builtin_return_address(0));
-       if (area == NULL)
-               return NULL;
-
-       /*
-        * This ensures that page tables are constructed for this region
-        * of kernel virtual address space and mapped into init_mm.
-        */
-       if (apply_to_page_range(&init_mm, (unsigned long)area->addr,
-                               size, f, ptes ? &ptes : NULL)) {
-               free_vm_area(area);
-               return NULL;
-       }
-
-       return area;
-}
-EXPORT_SYMBOL_GPL(alloc_vm_area);
-
 void free_vm_area(struct vm_struct *area)
 {
        struct vm_struct *ret;
-- 
2.28.0