lkml.org 
[lkml]   [2017]   [Dec]   [19]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 1/2] mm: Make follow_pte_pmd an inline
Date
From: Matthew Wilcox <mawilcox@microsoft.com>

The one user of follow_pte_pmd (dax) emits a sparse warning because
it doesn't know that follow_pte_pmd conditionally returns with the
pte/pmd locked. The required annotation is already there; it's just
in the wrong file.
---
include/linux/mm.h | 15 ++++++++++++++-
mm/memory.c | 16 +---------------
2 files changed, 15 insertions(+), 16 deletions(-)

diff --git a/include/linux/mm.h b/include/linux/mm.h
index ea818ff739cd..94a9d2149bd6 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -1314,7 +1314,7 @@ int copy_page_range(struct mm_struct *dst, struct mm_struct *src,
struct vm_area_struct *vma);
void unmap_mapping_range(struct address_space *mapping,
loff_t const holebegin, loff_t const holelen, int even_cows);
-int follow_pte_pmd(struct mm_struct *mm, unsigned long address,
+int __follow_pte_pmd(struct mm_struct *mm, unsigned long address,
unsigned long *start, unsigned long *end,
pte_t **ptepp, pmd_t **pmdpp, spinlock_t **ptlp);
int follow_pfn(struct vm_area_struct *vma, unsigned long address,
@@ -1324,6 +1324,19 @@ int follow_phys(struct vm_area_struct *vma, unsigned long address,
int generic_access_phys(struct vm_area_struct *vma, unsigned long addr,
void *buf, int len, int write);

+static inline int follow_pte_pmd(struct mm_struct *mm, unsigned long address,
+ unsigned long *start, unsigned long *end,
+ pte_t **ptepp, pmd_t **pmdpp, spinlock_t **ptlp)
+{
+ int res;
+
+ /* (void) is needed to make gcc happy */
+ (void) __cond_lock(*ptlp,
+ !(res = __follow_pte_pmd(mm, address, start, end,
+ ptepp, pmdpp, ptlp)));
+ return res;
+}
+
static inline void unmap_shared_mapping_range(struct address_space *mapping,
loff_t const holebegin, loff_t const holelen)
{
diff --git a/mm/memory.c b/mm/memory.c
index cfaba6287702..cb433662af21 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -4201,7 +4201,7 @@ int __pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long address)
}
#endif /* __PAGETABLE_PMD_FOLDED */

-static int __follow_pte_pmd(struct mm_struct *mm, unsigned long address,
+int __follow_pte_pmd(struct mm_struct *mm, unsigned long address,
unsigned long *start, unsigned long *end,
pte_t **ptepp, pmd_t **pmdpp, spinlock_t **ptlp)
{
@@ -4278,20 +4278,6 @@ static inline int follow_pte(struct mm_struct *mm, unsigned long address,
return res;
}

-int follow_pte_pmd(struct mm_struct *mm, unsigned long address,
- unsigned long *start, unsigned long *end,
- pte_t **ptepp, pmd_t **pmdpp, spinlock_t **ptlp)
-{
- int res;
-
- /* (void) is needed to make gcc happy */
- (void) __cond_lock(*ptlp,
- !(res = __follow_pte_pmd(mm, address, start, end,
- ptepp, pmdpp, ptlp)));
- return res;
-}
-EXPORT_SYMBOL(follow_pte_pmd);
-
/**
* follow_pfn - look up PFN at a user virtual address
* @vma: memory mapping
--
2.15.1
\
 
 \ /
  Last update: 2017-12-19 17:58    [W:0.149 / U:0.232 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site