Hi Christoph,
On Thu, Mar 28, 2024 at 09:46:29AM +0100, Christoph Hellwig wrote:
> follow_phys is only used by two callers in arch/x86/mm/pat/memtype.c.
> Move it there and hardcode the two arguments that get the same values
> passed by both callers.
>
> Signed-off-by: Christoph Hellwig <hch@xxxxxx>
> ---
> arch/x86/mm/pat/memtype.c | 23 +++++++++++++++++++++--
> include/linux/mm.h | 2 --
> mm/memory.c | 28 ----------------------------
> 3 files changed, 21 insertions(+), 32 deletions(-)
>
> diff --git a/arch/x86/mm/pat/memtype.c b/arch/x86/mm/pat/memtype.c
> index 0d72183b5dd028..c64f07b0fc2099 100644
> --- a/arch/x86/mm/pat/memtype.c
> +++ b/arch/x86/mm/pat/memtype.c
> @@ -947,6 +947,25 @@ static void free_pfn_range(u64 paddr, unsigned long size)
> memtype_free(paddr, paddr + size);
> }
>
> +static int follow_phys(struct vm_area_struct *vma, unsigned long *prot,
> + resource_size_t *phys)
> +{
> + pte_t *ptep, pte;
> + spinlock_t *ptl;
> +
> + if (!(vma->vm_flags & (VM_IO | VM_PFNMAP)))
> + return -EINVAL;
> +
> + if (follow_pte(vma->vm_mm, vma->vm_start, &ptep, &ptl))
> + return -EINVAL;
> +
> + pte = ptep_get(ptep);
> + *prot = pgprot_val(pte_pgprot(pte));
> + *phys = (resource_size_t)pte_pfn(pte) << PAGE_SHIFT;
> + pte_unmap_unlock(ptep, ptl);
memtype.c needs to include highmem.h for highmem-internal.h, otherwise I
get a build failure (ARCH=i386 allmodconfig):
In file included from include/linux/mm.h:30,
from include/linux/memblock.h:12,
from arch/x86/mm/pat/memtype.c:35:
arch/x86/mm/pat/memtype.c: In function 'follow_phys':
include/linux/pgtable.h:105:9: error: implicit declaration of function 'kunmap_local' [-Werror=implicit-function-declaration]
105 | kunmap_local((pte)); \
| ^~~~~~~~~~~~
include/linux/mm.h:3014:9: note: in expansion of macro 'pte_unmap'
3014 | pte_unmap(pte); \
| ^~~~~~~~~
arch/x86/mm/pat/memtype.c:965:9: note: in expansion of macro 'pte_unmap_unlock'
965 | pte_unmap_unlock(ptep, ptl);
| ^~~~~~~~~~~~~~~~
cc1: all warnings being treated as errors
Cheers,
Nathan
diff --git a/arch/x86/mm/pat/memtype.c b/arch/x86/mm/pat/memtype.c
index c64f07b0fc20..143d1e3d3fd2 100644
--- a/arch/x86/mm/pat/memtype.c
+++ b/arch/x86/mm/pat/memtype.c
@@ -39,6 +39,7 @@
#include <linux/pfn_t.h>
#include <linux/slab.h>
#include <linux/mm.h>
+#include <linux/highmem.h>
#include <linux/fs.h>
#include <linux/rbtree.h>
