Commit 5b34b76c authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Andrew Morton
Browse files

mm: move follow_phys to arch/x86/mm/pat/memtype.c 

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.

[david@redhat.com: conflict resolutions]
Link: https://lkml.kernel.org/r/20240403212131.929421-4-david@redhat.com
Link: https://lkml.kernel.org/r/20240324234542.2038726-4-hch@lst.de


Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Signed-off-by: default avatarDavid Hildenbrand <david@redhat.com>
Reviewed-by: default avatarDavid Hildenbrand <david@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fei Li <fei1.li@intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent cb10c28a

arch/x86/mm/pat/memtype.c

+28 −1
Original line number Diff line number Diff line
@@ -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>
@@ -947,6 +948,32 @@ 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);



	/* Never return PFNs of anon folios in COW mappings. */

	if (vm_normal_folio(vma, vma->vm_start, pte)) {

		pte_unmap_unlock(ptep, ptl);

		return -EINVAL;

	}



	*prot = pgprot_val(pte_pgprot(pte));

	*phys = (resource_size_t)pte_pfn(pte) << PAGE_SHIFT;

	pte_unmap_unlock(ptep, ptl);

	return 0;

}



static int get_pat_info(struct vm_area_struct *vma, resource_size_t *paddr,

		pgprot_t *pgprot)

{
@@ -964,7 +991,7 @@ static int get_pat_info(struct vm_area_struct *vma, resource_size_t *paddr, 
	 * detect the PFN. If we need the cachemode as well, we're out of luck

	 * for now and have to fail fork().

	 */

	if (!follow_phys(vma, vma->vm_start, 0, &prot, paddr)) {

	if (!follow_phys(vma, &prot, paddr)) {

		if (pgprot)

			*pgprot = __pgprot(prot);

		return 0;

include/linux/mm.h

+0 −2
Original line number Diff line number Diff line
@@ -2424,8 +2424,6 @@ int 
copy_page_range(struct vm_area_struct *dst_vma, struct vm_area_struct *src_vma);

int follow_pte(struct mm_struct *mm, unsigned long address,

	       pte_t **ptepp, spinlock_t **ptlp);

int follow_phys(struct vm_area_struct *vma, unsigned long address,

		unsigned int flags, unsigned long *prot, resource_size_t *phys);

int generic_access_phys(struct vm_area_struct *vma, unsigned long addr,

			void *buf, int len, int write);

mm/memory.c

+0 −32
Original line number Diff line number Diff line
@@ -5928,38 +5928,6 @@ int follow_pte(struct mm_struct *mm, unsigned long address, 
EXPORT_SYMBOL_GPL(follow_pte);



#ifdef CONFIG_HAVE_IOREMAP_PROT

int follow_phys(struct vm_area_struct *vma,

		unsigned long address, unsigned int flags,

		unsigned long *prot, resource_size_t *phys)

{

	int ret = -EINVAL;

	pte_t *ptep, pte;

	spinlock_t *ptl;



	if (!(vma->vm_flags & (VM_IO | VM_PFNMAP)))

		goto out;



	if (follow_pte(vma->vm_mm, address, &ptep, &ptl))

		goto out;

	pte = ptep_get(ptep);



	/* Never return PFNs of anon folios in COW mappings. */

	if (vm_normal_folio(vma, address, pte))

		goto unlock;



	if ((flags & FOLL_WRITE) && !pte_write(pte))

		goto unlock;



	*prot = pgprot_val(pte_pgprot(pte));

	*phys = (resource_size_t)pte_pfn(pte) << PAGE_SHIFT;



	ret = 0;

unlock:

	pte_unmap_unlock(ptep, ptl);

out:

	return ret;

}



/**

 * generic_access_phys - generic implementation for iomem mmap access

 * @vma: the vma to access