The patch titled
Subject: mm: move follow_phys to arch/x86/mm/pat/memtype.c
has been added to the -mm mm-unstable branch. Its filename is
mm-move-follow_phys-to-arch-x86-mm-pat-memtypec.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-move-follow_phys-to-arch-x86-mm-pat-memtypec.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next via the mm-everything
branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
and is updated there every 2-3 working days
------------------------------------------------------
From: Christoph Hellwig <hch@xxxxxx>
Subject: mm: move follow_phys to arch/x86/mm/pat/memtype.c
Date: Mon, 25 Mar 2024 07:45:42 +0800
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.
Link: https://lkml.kernel.org/r/20240324234542.2038726-4-hch@xxxxxx
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
Cc: Andy Lutomirski <luto@xxxxxxxxxx>
Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
Cc: Fei Li <fei1.li@xxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: David Hildenbrand <david@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
arch/x86/mm/pat/memtype.c | 22 ++++++++++++++++++++--
include/linux/mm.h | 2 --
mm/memory.c | 28 ----------------------------
3 files changed, 20 insertions(+), 32 deletions(-)
--- a/arch/x86/mm/pat/memtype.c~mm-move-follow_phys-to-arch-x86-mm-pat-memtypec
+++ a/arch/x86/mm/pat/memtype.c
@@ -947,6 +947,24 @@ static void free_pfn_range(u64 paddr, un
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);
+ return 0;
+}
+
/*
* track_pfn_copy is called when vma that is covering the pfnmap gets
* copied through copy_page_range().
@@ -966,7 +984,7 @@ int track_pfn_copy(struct vm_area_struct
* reserve the whole chunk covered by vma. We need the
* starting address and protection from pte.
*/
- if (follow_phys(vma, vma->vm_start, 0, &prot, &paddr)) {
+ if (follow_phys(vma, &prot, &paddr)) {
WARN_ON_ONCE(1);
return -EINVAL;
}
@@ -1053,7 +1071,7 @@ void untrack_pfn(struct vm_area_struct *
/* free the chunk starting from pfn or the whole chunk */
paddr = (resource_size_t)pfn << PAGE_SHIFT;
if (!paddr && !size) {
- if (follow_phys(vma, vma->vm_start, 0, &prot, &paddr)) {
+ if (follow_phys(vma, &prot, &paddr)) {
WARN_ON_ONCE(1);
return;
}
--- a/include/linux/mm.h~mm-move-follow_phys-to-arch-x86-mm-pat-memtypec
+++ a/include/linux/mm.h
@@ -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);
--- a/mm/memory.c~mm-move-follow_phys-to-arch-x86-mm-pat-memtypec
+++ a/mm/memory.c
@@ -5928,34 +5928,6 @@ out:
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);
-
- 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
_
Patches currently in -mm which might be from hch@xxxxxx are
virt-acrn-stop-using-follow_pfn.patch
mm-remove-follow_pfn.patch
mm-move-follow_phys-to-arch-x86-mm-pat-memtypec.patch
