Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull vfs pile #3 from Al Viro:
 "Assorted fixes and patches from the last cycle"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  [regression] chunk lost from bd9b51
  vfs: make mounts and mountstats honor root dir like mountinfo does
  vfs: cleanup show_mountinfo
  init: fix read-write root mount
  unfuck binfmt_misc.c (broken by commit e6084d4)
  vm_area_operations: kill ->migrate()
  new helper: iter_is_iovec()
  move_extent_per_page(): get rid of unused w_flags
  lustre: get rid of playing with ->fs
  btrfs: filp_open() returns ERR_PTR() on failure, not NULL...

4 files changed, 2 insertions, 28 deletions

diff --git a/mm/filemap.c b/mm/filemap.c
index e8905bc3cbd7..bd8543c6508f 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -2464,7 +2464,7 @@ ssize_t generic_perform_write(struct file *file,
         /*
          * Copies from kernel address space cannot fail (NFSD is a big user).
          */
-        if (segment_eq(get_fs(), KERNEL_DS))
+        if (!iter_is_iovec(i))
                 flags |= AOP_FLAG_UNINTERRUPTIBLE;
 
         do {
diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index f22c55947181..0e0961b8c39c 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -1041,10 +1041,6 @@ 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'
@@ -1124,7 +1120,6 @@ 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
diff --git a/mm/shmem.c b/mm/shmem.c
index 185836ba53ef..73ba1df7c8ba 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -1536,7 +1536,7 @@ static ssize_t shmem_file_read_iter(struct kiocb *iocb, struct iov_iter *to)
          * holes of a sparse file, we actually need to allocate those pages,
          * and even mark them dirty, so it cannot exceed the max_blocks limit.
          */
-        if (segment_eq(get_fs(), KERNEL_DS))
+        if (!iter_is_iovec(to))
                 sgp = SGP_DIRTY;
 
         index = *ppos >> PAGE_CACHE_SHIFT;