From: Ma Wupeng <[email protected]>
Patch #1 move follow_phys to memtype.c since only pat use this.
Patch #2 cleanup parameter flags in follow_phys.
Patch #3 drop the unnecessary WARN_ON_ONCE if follow_phys fails.
Changelog since v1:
- split patch #1 into two patches based on Boris's advise
Ma Wupeng (3):
x86/mm/pat: Move follow_phys to pat-related file
x86/mm/pat: Cleanup unused parameter in follow_phys
x86/mm/pat: Remove WARN_ON_ONCE if follow_phys fails
arch/x86/mm/pat/memtype.c | 33 +++++++++++++++++++++++++++------
include/linux/mm.h | 2 --
mm/memory.c | 28 ----------------------------
3 files changed, 27 insertions(+), 36 deletions(-)
--
2.25.1
From: Ma Wupeng <[email protected]>
Since only PAT in x86 use follow_phys(), move this to from memory.c to
memtype.c and make it static.
Since config HAVE_IOREMAP_PROT is selected by x86, drop this config macro.
Signed-off-by: Ma Wupeng <[email protected]>
---
arch/x86/mm/pat/memtype.c | 28 ++++++++++++++++++++++++++++
include/linux/mm.h | 2 --
mm/memory.c | 28 ----------------------------
3 files changed, 28 insertions(+), 30 deletions(-)
diff --git a/arch/x86/mm/pat/memtype.c b/arch/x86/mm/pat/memtype.c
index de10800cd4dd..4fb1e89f32e4 100644
--- a/arch/x86/mm/pat/memtype.c
+++ b/arch/x86/mm/pat/memtype.c
@@ -950,6 +950,34 @@ 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 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;
+
+ 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;
+}
+
/*
* track_pfn_copy is called when vma that is covering the pfnmap gets
* copied through copy_page_range().
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 5f16263d176d..226f2f7cefd7 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -2311,8 +2311,6 @@ int follow_pte(struct mm_struct *mm, unsigned long address,
pte_t **ptepp, spinlock_t **ptlp);
int follow_pfn(struct vm_area_struct *vma, unsigned long address,
unsigned long *pfn);
-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);
diff --git a/mm/memory.c b/mm/memory.c
index 0adf23ea5416..93ad6b45f426 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -5454,34 +5454,6 @@ int follow_pfn(struct vm_area_struct *vma, unsigned long address,
EXPORT_SYMBOL(follow_pfn);
#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;
-
- 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
--
2.25.1
From: Ma Wupeng <[email protected]>
Parameter flags is always zero in caller untrack_pfn() and
track_pfn_copy(). let's drop it.
Signed-off-by: Ma Wupeng <[email protected]>
---
arch/x86/mm/pat/memtype.c | 10 +++-------
1 file changed, 3 insertions(+), 7 deletions(-)
diff --git a/arch/x86/mm/pat/memtype.c b/arch/x86/mm/pat/memtype.c
index 4fb1e89f32e4..3ec025011c90 100644
--- a/arch/x86/mm/pat/memtype.c
+++ b/arch/x86/mm/pat/memtype.c
@@ -951,8 +951,7 @@ static void free_pfn_range(u64 paddr, unsigned long size)
}
static int follow_phys(struct vm_area_struct *vma, unsigned long address,
- unsigned int flags, unsigned long *prot,
- resource_size_t *phys)
+ unsigned long *prot, resource_size_t *phys)
{
int ret = -EINVAL;
pte_t *ptep, pte;
@@ -965,9 +964,6 @@ static int follow_phys(struct vm_area_struct *vma, unsigned long address,
goto out;
pte = *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;
@@ -997,7 +993,7 @@ int track_pfn_copy(struct vm_area_struct *vma)
* 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, vma->vm_start, &prot, &paddr)) {
WARN_ON_ONCE(1);
return -EINVAL;
}
@@ -1084,7 +1080,7 @@ void untrack_pfn(struct vm_area_struct *vma, unsigned long pfn,
/* 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, vma->vm_start, &prot, &paddr)) {
WARN_ON_ONCE(1);
return;
}
--
2.25.1
From: Ma Wupeng <[email protected]>
WARN_ON_ONCE here is not useful for solving problem since why this PA is
not valid is still unknown if follow_phys fails in
track_pfn_copy/untrack_pfn, Drop it.
Signed-off-by: Ma Wupeng <[email protected]>
---
arch/x86/mm/pat/memtype.c | 9 +++------
1 file changed, 3 insertions(+), 6 deletions(-)
diff --git a/arch/x86/mm/pat/memtype.c b/arch/x86/mm/pat/memtype.c
index 3ec025011c90..bda4b6b910c2 100644
--- a/arch/x86/mm/pat/memtype.c
+++ b/arch/x86/mm/pat/memtype.c
@@ -993,10 +993,9 @@ int track_pfn_copy(struct vm_area_struct *vma)
* reserve the whole chunk covered by vma. We need the
* starting address and protection from pte.
*/
- if (follow_phys(vma, vma->vm_start, &prot, &paddr)) {
- WARN_ON_ONCE(1);
+ if (follow_phys(vma, vma->vm_start, &prot, &paddr))
return -EINVAL;
- }
+
pgprot = __pgprot(prot);
return reserve_pfn_range(paddr, vma_size, &pgprot, 1);
}
@@ -1080,10 +1079,8 @@ void untrack_pfn(struct vm_area_struct *vma, unsigned long pfn,
/* 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, &prot, &paddr)) {
- WARN_ON_ONCE(1);
+ if (follow_phys(vma, vma->vm_start, &prot, &paddr))
return;
- }
size = vma->vm_end - vma->vm_start;
}
--
2.25.1