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

Pull third hunk of vfs changes from Al Viro:
 "This contains the ->direct_IO() changes from Omar + saner
  generic_write_checks() + dealing with fcntl()/{read,write}() races
  (mirroring O_APPEND/O_DIRECT into iocb->ki_flags and instead of
  repeatedly looking at ->f_flags, which can be changed by fcntl(2),
  check ->ki_flags - which cannot) + infrastructure bits for dhowells'
  d_inode annotations + Christophs switch of /dev/loop to
  vfs_iter_write()"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (30 commits)
  block: loop: switch to VFS ITER_BVEC
  configfs: Fix inconsistent use of file_inode() vs file->f_path.dentry->d_inode
  VFS: Make pathwalk use d_is_reg() rather than S_ISREG()
  VFS: Fix up debugfs to use d_is_dir() in place of S_ISDIR()
  VFS: Combine inode checks with d_is_negative() and d_is_positive() in pathwalk
  NFS: Don't use d_inode as a variable name
  VFS: Impose ordering on accesses of d_inode and d_flags
  VFS: Add owner-filesystem positive/negative dentry checks
  nfs: generic_write_checks() shouldn't be done on swapout...
  ocfs2: use __generic_file_write_iter()
  mirror O_APPEND and O_DIRECT into iocb->ki_flags
  switch generic_write_checks() to iocb and iter
  ocfs2: move generic_write_checks() before the alignment checks
  ocfs2_file_write_iter: stop messing with ppos
  udf_file_write_iter: reorder and simplify
  fuse: ->direct_IO() doesn't need generic_write_checks()
  ext4_file_write_iter: move generic_write_checks() up
  xfs_file_aio_write_checks: switch to iocb/iov_iter
  generic_write_checks(): drop isblk argument
  blkdev_write_iter: expand generic_file_checks() call in there
  ...

55 files changed, 691 insertions, 861 deletions

diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking
index 7c3f187d48bf..0a926e2ba3ab 100644
--- a/Documentation/filesystems/Locking
+++ b/Documentation/filesystems/Locking
@@ -196,7 +196,7 @@ prototypes:
         void (*invalidatepage) (struct page *, unsigned int, unsigned int);
         int (*releasepage) (struct page *, int);
         void (*freepage)(struct page *);
-        int (*direct_IO)(int, struct kiocb *, struct iov_iter *iter, loff_t offset);
+        int (*direct_IO)(struct kiocb *, struct iov_iter *iter, loff_t offset);
         int (*migratepage)(struct address_space *, struct page *, struct page *);
         int (*launder_page)(struct page *);
         int (*is_partially_uptodate)(struct page *, unsigned long, unsigned long);
diff --git a/Documentation/filesystems/vfs.txt b/Documentation/filesystems/vfs.txt
index 207cdca68bed..5d833b32bbcd 100644
--- a/Documentation/filesystems/vfs.txt
+++ b/Documentation/filesystems/vfs.txt
@@ -590,7 +590,7 @@ struct address_space_operations {
         void (*invalidatepage) (struct page *, unsigned int, unsigned int);
         int (*releasepage) (struct page *, int);
         void (*freepage)(struct page *);
-        ssize_t (*direct_IO)(int, struct kiocb *, struct iov_iter *iter, loff_t offset);
+        ssize_t (*direct_IO)(struct kiocb *, struct iov_iter *iter, loff_t offset);
         /* migrate the contents of a page to the specified target */
         int (*migratepage) (struct page *, struct page *);
         int (*launder_page) (struct page *);
diff --git a/drivers/block/loop.c b/drivers/block/loop.c
index c4fd1e45ce1e..ae3fcb4199e9 100644
--- a/drivers/block/loop.c
+++ b/drivers/block/loop.c
@@ -88,28 +88,6 @@ static int part_shift;
 
 static struct workqueue_struct *loop_wq;
 
-/*
- * Transfer functions
- */
-static int transfer_none(struct loop_device *lo, int cmd,
-                         struct page *raw_page, unsigned raw_off,
-                         struct page *loop_page, unsigned loop_off,
-                         int size, sector_t real_block)
-{
-        char *raw_buf = kmap_atomic(raw_page) + raw_off;
-        char *loop_buf = kmap_atomic(loop_page) + loop_off;
-
-        if (cmd == READ)
-                memcpy(loop_buf, raw_buf, size);
-        else
-                memcpy(raw_buf, loop_buf, size);
-
-        kunmap_atomic(loop_buf);
-        kunmap_atomic(raw_buf);
-        cond_resched();
-        return 0;
-}
-
 static int transfer_xor(struct loop_device *lo, int cmd,
                         struct page *raw_page, unsigned raw_off,
                         struct page *loop_page, unsigned loop_off,
@@ -148,14 +126,13 @@ static int xor_init(struct loop_device *lo, const struct loop_info64 *info)
 
 static struct loop_func_table none_funcs = {
         .number = LO_CRYPT_NONE,
-        .transfer = transfer_none,
-};      
+}; 
 
 static struct loop_func_table xor_funcs = {
         .number = LO_CRYPT_XOR,
         .transfer = transfer_xor,
         .init = xor_init
-};      
+}; 
 
 /* xfer_funcs[0] is special - its release function is never called */
 static struct loop_func_table *xfer_funcs[MAX_LO_CRYPT] = {
@@ -215,207 +192,169 @@ lo_do_transfer(struct loop_device *lo, int cmd,
                struct page *lpage, unsigned loffs,
                int size, sector_t rblock)
 {
-        if (unlikely(!lo->transfer))
+        int ret;
+
+        ret = lo->transfer(lo, cmd, rpage, roffs, lpage, loffs, size, rblock);
+        if (likely(!ret))
                 return 0;
 
-        return lo->transfer(lo, cmd, rpage, roffs, lpage, loffs, size, rblock);
+        printk_ratelimited(KERN_ERR
+                "loop: Transfer error at byte offset %llu, length %i.\n",
+                (unsigned long long)rblock << 9, size);
+        return ret;
 }
 
-/**
- * __do_lo_send_write - helper for writing data to a loop device
- *
+static int lo_write_bvec(struct file *file, struct bio_vec *bvec, loff_t *ppos)