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

Pull vfs pile 1 from Al Viro:
 "Unfortunately, this merge window it'll have a be a lot of small piles -
  my fault, actually, for not keeping #for-next in anything that would
  resemble a sane shape ;-/

  This pile: assorted fixes (the first 3 are -stable fodder, IMO) and
  cleanups + %pd/%pD formats (dentry/file pathname, up to 4 last
  components) + several long-standing patches from various folks.

  There definitely will be a lot more (starting with Miklos'
  check_submount_and_drop() series)"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (26 commits)
  direct-io: Handle O_(D)SYNC AIO
  direct-io: Implement generic deferred AIO completions
  add formats for dentry/file pathnames
  kvm eventfd: switch to fdget
  powerpc kvm: use fdget
  switch fchmod() to fdget
  switch epoll_ctl() to fdget
  switch copy_module_from_fd() to fdget
  git simplify nilfs check for busy subtree
  ibmasmfs: don't bother passing superblock when not needed
  don't pass superblock to hypfs_{mkdir,create*}
  don't pass superblock to hypfs_diag_create_files
  don't pass superblock to hypfs_vm_create_files()
  oprofile: get rid of pointless forward declarations of struct super_block
  oprofilefs_create_...() do not need superblock argument
  oprofilefs_mkdir() doesn't need superblock argument
  don't bother with passing superblock to oprofile_create_stats_files()
  oprofile: don't bother with passing superblock to ->create_files()
  don't bother passing sb to oprofile_create_files()
  coh901318: don't open-code simple_read_from_buffer()
  ...

fs/ext4/ext4.h

@@ -180,7 +180,6 @@ struct ext4_map_blocks {
  * Flags for ext4_io_end->flags
  */
 #define	EXT4_IO_END_UNWRITTEN	0x0001
-#define EXT4_IO_END_DIRECT	0x0002
 
 /*
  * For converting uninitialized extents on a work queue. 'handle' is used for
@@ -196,8 +195,6 @@ typedef struct ext4_io_end {
 	unsigned int		flag;		/* unwritten or not */
 	loff_t			offset;		/* offset in the file */
 	ssize_t			size;		/* size of the extent */
-	struct kiocb		*iocb;		/* iocb struct for AIO */
-	int			result;		/* error value for AIO */
 	atomic_t		count;		/* reference counter */
 } ext4_io_end_t;
 
@@ -914,11 +911,9 @@ struct ext4_inode_info {
 	 * Completed IOs that need unwritten extents handling and don't have
 	 * transaction reserved
 	 */
-	struct list_head i_unrsv_conversion_list;
 	atomic_t i_ioend_count;	/* Number of outstanding io_end structs */
 	atomic_t i_unwritten; /* Nr. of inflight conversions pending */
 	struct work_struct i_rsv_conversion_work;
-	struct work_struct i_unrsv_conversion_work;
 
 	spinlock_t i_block_reservation_lock;
 
@@ -1290,8 +1285,6 @@ struct ext4_sb_info {
 	struct flex_groups *s_flex_groups;
 	ext4_group_t s_flex_groups_allocated;
 
-	/* workqueue for unreserved extent convertions (dio) */
-	struct workqueue_struct *unrsv_conversion_wq;
 	/* workqueue for reserved extent conversions (buffered io) */
 	struct workqueue_struct *rsv_conversion_wq;
 
@@ -1354,9 +1347,6 @@ static inline void ext4_set_io_unwritten_flag(struct inode *inode,
 					      struct ext4_io_end *io_end)
 {
 	if (!(io_end->flag & EXT4_IO_END_UNWRITTEN)) {
-		/* Writeback has to have coversion transaction reserved */
-		WARN_ON(EXT4_SB(inode->i_sb)->s_journal && !io_end->handle &&
-			!(io_end->flag & EXT4_IO_END_DIRECT));
 		io_end->flag |= EXT4_IO_END_UNWRITTEN;
 		atomic_inc(&EXT4_I(inode)->i_unwritten);
 	}
@@ -2760,7 +2750,6 @@ extern void ext4_put_io_end_defer(ext4_io_end_t *io_end);
 extern void ext4_io_submit_init(struct ext4_io_submit *io,
 				struct writeback_control *wbc);
 extern void ext4_end_io_rsv_work(struct work_struct *work);
-extern void ext4_end_io_unrsv_work(struct work_struct *work);
 extern void ext4_io_submit(struct ext4_io_submit *io);
 extern int ext4_bio_write_page(struct ext4_io_submit *io,
 			       struct page *page,

fs/ext4/file.c

@@ -149,7 +149,7 @@ ext4_file_dio_write(struct kiocb *iocb, const struct iovec *iov,
 	ret = __generic_file_aio_write(iocb, iov, nr_segs, &iocb->ki_pos);
 	mutex_unlock(&inode->i_mutex);
 
-	if (ret > 0 || ret == -EIOCBQUEUED) {
+	if (ret > 0) {
 		ssize_t err;
 
 		err = generic_write_sync(file, pos, ret);

fs/ext4/inode.c

@@ -727,8 +727,12 @@ static int _ext4_get_block(struct inode *inode, sector_t iblock,
 
 	ret = ext4_map_blocks(handle, inode, &map, flags);
 	if (ret > 0) {
+		ext4_io_end_t *io_end = ext4_inode_aio(inode);
+
 		map_bh(bh, inode->i_sb, map.m_pblk);
 		bh->b_state = (bh->b_state & ~EXT4_MAP_FLAGS) | map.m_flags;
+		if (io_end && io_end->flag & EXT4_IO_END_UNWRITTEN)
+			set_buffer_defer_completion(bh);
 		bh->b_size = inode->i_sb->s_blocksize * map.m_len;
 		ret = 0;
 	}
@@ -3024,19 +3028,13 @@ static int ext4_get_block_write_nolock(struct inode *inode, sector_t iblock,
 }
 
 static void ext4_end_io_dio(struct kiocb *iocb, loff_t offset,
-			    ssize_t size, void *private, int ret,
-			    bool is_async)
+			    ssize_t size, void *private)
 {
-	struct inode *inode = file_inode(iocb->ki_filp);
         ext4_io_end_t *io_end = iocb->private;
 
 	/* if not async direct IO just return */
-	if (!io_end) {
-		inode_dio_done(inode);
-		if (is_async)
-			aio_complete(iocb, ret, 0);
+	if (!io_end)
 		return;
-	}
 
 	ext_debug("ext4_end_io_dio(): io_end 0x%p "
 		  "for inode %lu, iocb 0x%p, offset %llu, size %zd\n",
@@ -3046,11 +3044,7 @@ static void ext4_end_io_dio(struct kiocb *iocb, loff_t offset,
 	iocb->private = NULL;
 	io_end->offset = offset;
 	io_end->size = size;
-	if (is_async) {
-		io_end->iocb = iocb;
-		io_end->result = ret;
-	}
-	ext4_put_io_end_defer(io_end);
+	ext4_put_io_end(io_end);
 }
 
 /*
@@ -3135,7 +3129,6 @@ static ssize_t ext4_ext_direct_IO(int rw, struct kiocb *iocb,
 			ret = -ENOMEM;
 			goto retake_lock;
 		}
-		io_end->flag |= EXT4_IO_END_DIRECT;
 		/*
 		 * Grab reference for DIO. Will be dropped in ext4_end_io_dio()
 		 */
@@ -3180,13 +3173,6 @@ static ssize_t ext4_ext_direct_IO(int rw, struct kiocb *iocb,
 		if (ret <= 0 && ret != -EIOCBQUEUED && iocb->private) {
 			WARN_ON(iocb->private != io_end);
 			WARN_ON(io_end->flag & EXT4_IO_END_UNWRITTEN);
-			WARN_ON(io_end->iocb);
-			/*
-			 * Generic code already did inode_dio_done() so we
-			 * have to clear EXT4_IO_END_DIRECT to not do it for
-			 * the second time.
-			 */
-			io_end->flag = 0;
 			ext4_put_io_end(io_end);
 			iocb->private = NULL;
 		}

fs/ext4/page-io.c

@@ -123,10 +123,6 @@ static void ext4_release_io_end(ext4_io_end_t *io_end)
 		ext4_finish_bio(bio);
 		bio_put(bio);
 	}
-	if (io_end->flag & EXT4_IO_END_DIRECT)
-		inode_dio_done(io_end->inode);
-	if (io_end->iocb)
-		aio_complete(io_end->iocb, io_end->result, 0);
 	kmem_cache_free(io_end_cachep, io_end);
 }
 
@@ -204,19 +200,14 @@ static void ext4_add_complete_io(ext4_io_end_t *io_end)
 	struct workqueue_struct *wq;
 	unsigned long flags;
 
-	BUG_ON(!(io_end->flag & EXT4_IO_END_UNWRITTEN));
+	/* Only reserved conversions from writeback should enter here */
+	WARN_ON(!(io_end->flag & EXT4_IO_END_UNWRITTEN));
+	WARN_ON(!io_end->handle);
 	spin_lock_irqsave(&ei->i_completed_io_lock, flags);
-	if (io_end->handle) {
-		wq = EXT4_SB(io_end->inode->i_sb)->rsv_conversion_wq;
-		if (list_empty(&ei->i_rsv_conversion_list))
-			queue_work(wq, &ei->i_rsv_conversion_work);
-		list_add_tail(&io_end->list, &ei->i_rsv_conversion_list);
-	} else {
-		wq = EXT4_SB(io_end->inode->i_sb)->unrsv_conversion_wq;
-		if (list_empty(&ei->i_unrsv_conversion_list))
-			queue_work(wq, &ei->i_unrsv_conversion_work);
-		list_add_tail(&io_end->list, &ei->i_unrsv_conversion_list);
-	}
+	wq = EXT4_SB(io_end->inode->i_sb)->rsv_conversion_wq;
+	if (list_empty(&ei->i_rsv_conversion_list))
+		queue_work(wq, &ei->i_rsv_conversion_work);
+	list_add_tail(&io_end->list, &ei->i_rsv_conversion_list);
 	spin_unlock_irqrestore(&ei->i_completed_io_lock, flags);
 }
 
@@ -256,13 +247,6 @@ void ext4_end_io_rsv_work(struct work_struct *work)
 	ext4_do_flush_completed_IO(&ei->vfs_inode, &ei->i_rsv_conversion_list);
 }
 
-void ext4_end_io_unrsv_work(struct work_struct *work)
-{
-	struct ext4_inode_info *ei = container_of(work, struct ext4_inode_info,
-						  i_unrsv_conversion_work);
-	ext4_do_flush_completed_IO(&ei->vfs_inode, &ei->i_unrsv_conversion_list);
-}
-
 ext4_io_end_t *ext4_init_io_end(struct inode *inode, gfp_t flags)
 {
 	ext4_io_end_t *io = kmem_cache_zalloc(io_end_cachep, flags);

fs/ext4/super.c

@@ -762,9 +762,7 @@ static void ext4_put_super(struct super_block *sb)
 	ext4_unregister_li_request(sb);
 	dquot_disable(sb, -1, DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED);
 
-	flush_workqueue(sbi->unrsv_conversion_wq);
 	flush_workqueue(sbi->rsv_conversion_wq);
-	destroy_workqueue(sbi->unrsv_conversion_wq);
 	destroy_workqueue(sbi->rsv_conversion_wq);
 
 	if (sbi->s_journal) {
@@ -875,14 +873,12 @@ static struct inode *ext4_alloc_inode(struct super_block *sb)
 #endif
 	ei->jinode = NULL;
 	INIT_LIST_HEAD(&ei->i_rsv_conversion_list);
-	INIT_LIST_HEAD(&ei->i_unrsv_conversion_list);
 	spin_lock_init(&ei->i_completed_io_lock);
 	ei->i_sync_tid = 0;
 	ei->i_datasync_tid = 0;
 	atomic_set(&ei->i_ioend_count, 0);
 	atomic_set(&ei->i_unwritten, 0);
 	INIT_WORK(&ei->i_rsv_conversion_work, ext4_end_io_rsv_work);
-	INIT_WORK(&ei->i_unrsv_conversion_work, ext4_end_io_unrsv_work);
 
 	return &ei->vfs_inode;
 }
@@ -3995,14 +3991,6 @@ no_journal:
 		goto failed_mount4;
 	}
 
-	EXT4_SB(sb)->unrsv_conversion_wq =
-		alloc_workqueue("ext4-unrsv-conversion", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
-	if (!EXT4_SB(sb)->unrsv_conversion_wq) {
-		printk(KERN_ERR "EXT4-fs: failed to create workqueue\n");
-		ret = -ENOMEM;
-		goto failed_mount4;
-	}
-
 	/*
 	 * The jbd2_journal_load will have done any necessary log recovery,
 	 * so we can safely mount the rest of the filesystem now.
@@ -4156,8 +4144,6 @@ failed_mount4:
 	ext4_msg(sb, KERN_ERR, "mount failed");
 	if (EXT4_SB(sb)->rsv_conversion_wq)
 		destroy_workqueue(EXT4_SB(sb)->rsv_conversion_wq);
-	if (EXT4_SB(sb)->unrsv_conversion_wq)
-		destroy_workqueue(EXT4_SB(sb)->unrsv_conversion_wq);
 failed_mount_wq:
 	if (sbi->s_journal) {
 		jbd2_journal_destroy(sbi->s_journal);
@@ -4605,7 +4591,6 @@ static int ext4_sync_fs(struct super_block *sb, int wait)
 
 	trace_ext4_sync_fs(sb, wait);
 	flush_workqueue(sbi->rsv_conversion_wq);
-	flush_workqueue(sbi->unrsv_conversion_wq);
 	/*
 	 * Writeback quota in non-journalled quota case - journalled quota has
 	 * no dirty dquots
@@ -4641,7 +4626,6 @@ static int ext4_sync_fs_nojournal(struct super_block *sb, int wait)
 
 	trace_ext4_sync_fs(sb, wait);
 	flush_workqueue(EXT4_SB(sb)->rsv_conversion_wq);
-	flush_workqueue(EXT4_SB(sb)->unrsv_conversion_wq);
 	dquot_writeback_dquots(sb, -1);
 	if (wait && test_opt(sb, BARRIER))
 		ret = blkdev_issue_flush(sb->s_bdev, GFP_KERNEL, NULL);