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/20201002122204.1534411-11-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> Cc: Uladzislau Rezki (Sony) <urezki@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) _
