mm/mprotect.c: fix compilation warning because of unused 'mm' variable

Since 0cbe3e26abe0 ("mm: update ptep_modify_prot_start/commit to take
vm_area_struct as arg") the only place that uses the local 'mm' variable
in change_pte_range() is the call to set_pte_at().

Many architectures define set_pte_at() as macro that does not use the 'mm'
parameter, which generates the following compilation warning:

 CC      mm/mprotect.o
mm/mprotect.c: In function 'change_pte_range':
mm/mprotect.c:42:20: warning: unused variable 'mm' [-Wunused-variable]
  struct mm_struct *mm = vma->vm_mm;
                    ^~

Fix it by passing vma->mm to set_pte_at() and dropping the local 'mm'
variable in change_pte_range().

[liu.song.a23@gmail.com: fix missed conversions]
Link: http://lkml.kernel.org/r/CAPhsuW6wcQgYLHNdBdw6m0YiR4RWsS4XzfpSKU7wBLLeOCTbpw@mail.gmail.comLink:
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Song Liu <liu.song.a23@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/mm/mprotect.c b/mm/mprotect.c
index 65242f1e445779c19c0ed327ff76aac3afe2bdad..bf38dfbbb4b4748e53913a2a6dde7e2a2b8efee7 100644 (file)
--- a/mm/mprotect.c
+++ b/mm/mprotect.c
@@ -39,7 +39,6 @@ static unsigned long change_pte_range(struct vm_area_struct *vma, pmd_t *pmd,
                unsigned long addr, unsigned long end, pgprot_t newprot,
                int dirty_accountable, int prot_numa)
 {
-       struct mm_struct *mm = vma->vm_mm;
        pte_t *pte, oldpte;
        spinlock_t *ptl;
        unsigned long pages = 0;
@@ -136,7 +135,7 @@ static unsigned long change_pte_range(struct vm_area_struct *vma, pmd_t *pmd,
                                newpte = swp_entry_to_pte(entry);
                                if (pte_swp_soft_dirty(oldpte))
                                        newpte = pte_swp_mksoft_dirty(newpte);
-                               set_pte_at(mm, addr, pte, newpte);
+                               set_pte_at(vma->vm_mm, addr, pte, newpte);
 
                                pages++;
                        }
@@ -150,7 +149,7 @@ static unsigned long change_pte_range(struct vm_area_struct *vma, pmd_t *pmd,
                                 */
                                make_device_private_entry_read(&entry);
                                newpte = swp_entry_to_pte(entry);
-                               set_pte_at(mm, addr, pte, newpte);
+                               set_pte_at(vma->vm_mm, addr, pte, newpte);
 
                                pages++;
                        }