The patch titled
Subject: x86/xen: open code alloc_vm_area in arch_gnttab_valloc
has been added to the -mm tree. Its filename is
x86-xen-open-code-alloc_vm_area-in-arch_gnttab_valloc.patch
This patch should soon appear at
https://ozlabs.org/~akpm/mmots/broken-out/x86-xen-open-code-alloc_vm_area-in-arch_gnttab_valloc.patch
and later at
https://ozlabs.org/~akpm/mmotm/broken-out/x86-xen-open-code-alloc_vm_area-in-arch_gnttab_valloc.patch
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------------------------------------------------------
From: Christoph Hellwig <hch@xxxxxx>
Subject: x86/xen: open code alloc_vm_area in arch_gnttab_valloc
Open code alloc_vm_area in the last remaining caller.
Link: https://lkml.kernel.org/r/20200918163724.2511-7-hch@xxxxxx
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
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(-)
--- a/arch/x86/xen/grant-table.c~x86-xen-open-code-alloc_vm_area-in-arch_gnttab_valloc
+++ a/arch/x86/xen/grant-table.c
@@ -90,19 +90,32 @@ void arch_gnttab_unmap(void *shared, uns
}
}
+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)
--- a/include/linux/vmalloc.h~x86-xen-open-code-alloc_vm_area-in-arch_gnttab_valloc
+++ a/include/linux/vmalloc.h
@@ -168,6 +168,7 @@ extern struct vm_struct *__get_vm_area_c
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_pe
}
#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);
--- a/mm/nommu.c~x86-xen-open-code-alloc_vm_area-in-arch_gnttab_valloc
+++ a/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();
--- a/mm/vmalloc.c~x86-xen-open-code-alloc_vm_area-in-arch_gnttab_valloc
+++ a/mm/vmalloc.c
@@ -3077,54 +3077,6 @@ int remap_vmalloc_range(struct vm_area_s
}
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;
_
Patches currently in -mm which might be from hch@xxxxxx are
zsmalloc-switch-from-alloc_vm_area-to-get_vm_area.patch
mm-add-a-vmap_pfn-function.patch
drm-i915-use-vmap-in-shmem_pin_map.patch
drm-i915-use-vmap-in-i915_gem_object_map.patch
xen-xenbus-use-apply_to_page_range-directly-in-xenbus_map_ring_pv.patch
x86-xen-open-code-alloc_vm_area-in-arch_gnttab_valloc.patch
