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
Replace the last call to alloc_vm_area with an open coded version using an
iterator in struct gnttab_vm_area instead of the triple indirection magic
in alloc_vm_area.
Link: https://lkml.kernel.org/r/20200930175133.1252382-10-hch@xxxxxx
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@xxxxxxxxxx>
Cc: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx>
Cc: Jani Nikula <jani.nikula@xxxxxxxxxxxxxxx>
Cc: Joonas Lahtinen <joonas.lahtinen@xxxxxxxxxxxxxxx>
Cc: Juergen Gross <jgross@xxxxxxxx>
Cc: Matthew Auld <matthew.auld@xxxxxxxxx>
Cc: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx>
Cc: Minchan Kim <minchan@xxxxxxxxxx>
Cc: Nitin Gupta <ngupta@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Rodrigo Vivi <rodrigo.vivi@xxxxxxxxx>
Cc: Stefano Stabellini <sstabellini@xxxxxxxxxx>
Cc: Tvrtko Ursulin <tvrtko.ursulin@xxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
arch/x86/xen/grant-table.c | 27 ++++++++++++++++++++-------
1 file changed, 20 insertions(+), 7 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
@@ -25,6 +25,7 @@
static struct gnttab_vm_area {
struct vm_struct *area;
pte_t **ptes;
+ int idx;
} gnttab_shared_vm_area, gnttab_status_vm_area;
int arch_gnttab_map_shared(unsigned long *frames, unsigned long nr_gframes,
@@ -90,19 +91,31 @@ void arch_gnttab_unmap(void *shared, uns
}
}
+static int gnttab_apply(pte_t *pte, unsigned long addr, void *data)
+{
+ struct gnttab_vm_area *area = data;
+
+ area->ptes[area->idx++] = pte;
+ 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))
+ 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)
_
Patches currently in -mm which might be from hch@xxxxxx are
mm-add-a-vm_map_put_pages-flag-for-vmap.patch
mm-add-a-vmap_pfn-function.patch
mm-allow-a-null-fn-callback-in-apply_to_page_range.patch
zsmalloc-switch-from-alloc_vm_area-to-get_vm_area.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
mm-remove-alloc_vm_area.patch
