mm: add unmap_mapping_pages()
Several users of unmap_mapping_range() would prefer to express their
range in pages rather than bytes. Unfortuately, on a 32-bit kernel, you
have to remember to cast your page number to a 64-bit type before
shifting it, and four places in the current tree didn't remember to do
that. That's a sign of a bad interface.
Conveniently, unmap_mapping_range() actually converts from bytes into
pages, so hoist the guts of unmap_mapping_range() into a new function
unmap_mapping_pages() and convert the callers which want to use pages.
Link: http://lkml.kernel.org/r/20171206142627.GD32044@bombadil.infradead.org
Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
Reported-by: "zhangyi (F)" <yi.zhang@huawei.com>
Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 7fc9238..173d248 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -1312,8 +1312,6 @@ void free_pgd_range(struct mmu_gather *tlb, unsigned long addr,
unsigned long end, unsigned long floor, unsigned long ceiling);
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,
unsigned long *start, unsigned long *end,
pte_t **ptepp, pmd_t **pmdpp, spinlock_t **ptlp);
@@ -1324,12 +1322,6 @@ 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 void unmap_shared_mapping_range(struct address_space *mapping,
- loff_t const holebegin, loff_t const holelen)
-{
- unmap_mapping_range(mapping, holebegin, holelen, 0);
-}
-
extern void truncate_pagecache(struct inode *inode, loff_t new);
extern void truncate_setsize(struct inode *inode, loff_t newsize);
void pagecache_isize_extended(struct inode *inode, loff_t from, loff_t to);
@@ -1344,6 +1336,10 @@ extern int handle_mm_fault(struct vm_area_struct *vma, unsigned long address,
extern int fixup_user_fault(struct task_struct *tsk, struct mm_struct *mm,
unsigned long address, unsigned int fault_flags,
bool *unlocked);
+void unmap_mapping_pages(struct address_space *mapping,
+ pgoff_t start, pgoff_t nr, bool even_cows);
+void unmap_mapping_range(struct address_space *mapping,
+ loff_t const holebegin, loff_t const holelen, int even_cows);
#else
static inline int handle_mm_fault(struct vm_area_struct *vma,
unsigned long address, unsigned int flags)
@@ -1360,10 +1356,20 @@ static inline int fixup_user_fault(struct task_struct *tsk,
BUG();
return -EFAULT;
}
+static inline void unmap_mapping_pages(struct address_space *mapping,
+ pgoff_t start, pgoff_t nr, bool even_cows) { }
+static inline void unmap_mapping_range(struct address_space *mapping,
+ loff_t const holebegin, loff_t const holelen, int even_cows) { }
#endif
-extern int access_process_vm(struct task_struct *tsk, unsigned long addr, void *buf, int len,
- unsigned int gup_flags);
+static inline void unmap_shared_mapping_range(struct address_space *mapping,
+ loff_t const holebegin, loff_t const holelen)
+{
+ unmap_mapping_range(mapping, holebegin, holelen, 0);
+}
+
+extern int access_process_vm(struct task_struct *tsk, unsigned long addr,
+ void *buf, int len, unsigned int gup_flags);
extern int access_remote_vm(struct mm_struct *mm, unsigned long addr,
void *buf, int len, unsigned int gup_flags);
extern int __access_remote_vm(struct task_struct *tsk, struct mm_struct *mm,