vm_area_operations: kill ->migrate()

the only instance this method has ever grown was one in kernfs -
one that call ->migrate() of another vm_ops if it exists.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

5 files changed, 0 insertions, 60 deletions

diff --git a/fs/kernfs/file.c b/fs/kernfs/file.c
index 697390ea47b8..ddc9f9612f16 100644
--- a/fs/kernfs/file.c
+++ b/fs/kernfs/file.c
@@ -448,27 +448,6 @@ static struct mempolicy *kernfs_vma_get_policy(struct vm_area_struct *vma,
         return pol;
 }
 
-static int kernfs_vma_migrate(struct vm_area_struct *vma,
-                              const nodemask_t *from, const nodemask_t *to,
-                              unsigned long flags)
-{
-        struct file *file = vma->vm_file;
-        struct kernfs_open_file *of = kernfs_of(file);
-        int ret;
-
-        if (!of->vm_ops)
-                return 0;
-
-        if (!kernfs_get_active(of->kn))
-                return 0;
-
-        ret = 0;
-        if (of->vm_ops->migrate)
-                ret = of->vm_ops->migrate(vma, from, to, flags);
-
-        kernfs_put_active(of->kn);
-        return ret;
-}
 #endif
 
 static const struct vm_operations_struct kernfs_vm_ops = {
@@ -479,7 +458,6 @@ static const struct vm_operations_struct kernfs_vm_ops = {
 #ifdef CONFIG_NUMA
         .set_policy     = kernfs_vma_set_policy,
         .get_policy     = kernfs_vma_get_policy,
-        .migrate        = kernfs_vma_migrate,
 #endif
 };
 
diff --git a/include/linux/migrate.h b/include/linux/migrate.h
index 01aad3ed89ec..fab9b32ace8e 100644
--- a/include/linux/migrate.h
+++ b/include/linux/migrate.h
@@ -36,9 +36,6 @@ extern int migrate_pages(struct list_head *l, new_page_t new, free_page_t free,
 
 extern int migrate_prep(void);
 extern int migrate_prep_local(void);
-extern int migrate_vmas(struct mm_struct *mm,
-                const nodemask_t *from, const nodemask_t *to,
-                unsigned long flags);
 extern void migrate_page_copy(struct page *newpage, struct page *page);
 extern int migrate_huge_page_move_mapping(struct address_space *mapping,
                                   struct page *newpage, struct page *page);
@@ -57,13 +54,6 @@ static inline int migrate_pages(struct list_head *l, new_page_t new,
 static inline int migrate_prep(void) { return -ENOSYS; }
 static inline int migrate_prep_local(void) { return -ENOSYS; }
 
-static inline int migrate_vmas(struct mm_struct *mm,
-                const nodemask_t *from, const nodemask_t *to,
-                unsigned long flags)
-{
-        return -ENOSYS;
-}
-
 static inline void migrate_page_copy(struct page *newpage,
                                      struct page *page) {}
 
diff --git a/include/linux/mm.h b/include/linux/mm.h
index c0a67b894c4c..f80d0194c9bc 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -286,8 +286,6 @@ struct vm_operations_struct {
          */
         struct mempolicy *(*get_policy)(struct vm_area_struct *vma,
                                         unsigned long addr);
-        int (*migrate)(struct vm_area_struct *vma, const nodemask_t *from,
-                const nodemask_t *to, unsigned long flags);
 #endif
         /* called by sys_remap_file_pages() to populate non-linear mapping */
         int (*remap_pages)(struct vm_area_struct *vma, unsigned long addr,
diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index e58725aff7e9..c1b273f1837b 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -1047,10 +1047,6 @@ int do_migrate_pages(struct mm_struct *mm, const nodemask_t *from,
 
         down_read(&mm->mmap_sem);
 
-        err = migrate_vmas(mm, from, to, flags);
-        if (err)
-                goto out;
-
         /*
          * Find a 'source' bit set in 'tmp' whose corresponding 'dest'
          * bit in 'to' is not also set in 'tmp'.  Clear the found 'source'
@@ -1130,7 +1126,6 @@ int do_migrate_pages(struct mm_struct *mm, const nodemask_t *from,
                 if (err < 0)
                         break;
         }
-out:
         up_read(&mm->mmap_sem);
         if (err < 0)
                 return err;
diff --git a/mm/migrate.c b/mm/migrate.c
index b1d02127e1be..344cdf692fc8 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -1536,27 +1536,6 @@ out:
         return err;
 }
 
-/*
- * Call migration functions in the vma_ops that may prepare
- * memory in a vm for migration. migration functions may perform
- * the migration for vmas that do not have an underlying page struct.
- */
-int migrate_vmas(struct mm_struct *mm, const nodemask_t *to,
-        const nodemask_t *from, unsigned long flags)
-{
-        struct vm_area_struct *vma;
-        int err = 0;
-
-        for (vma = mm->mmap; vma && !err; vma = vma->vm_next) {
-                if (vma->vm_ops && vma->vm_ops->migrate) {
-                        err = vma->vm_ops->migrate(vma, to, from, flags);
-                        if (err)
-                                break;
-                }
-        }
-        return err;
-}
-
 #ifdef CONFIG_NUMA_BALANCING
 /*
  * Returns true if this is a safe migration target node for misplaced NUMA