Merge tag 'writeback' of git://git.kernel.org/pub/scm/linux/kernel/gi…

…t/wfg/linux

Pull writeback tree from Wu Fengguang:
 "Mainly from Jan Kara to avoid iput() in the flusher threads."

* tag 'writeback' of git://git.kernel.org/pub/scm/linux/kernel/git/wfg/linux:
  writeback: Avoid iput() from flusher thread
  vfs: Rename end_writeback() to clear_inode()
  vfs: Move waiting for inode writeback from end_writeback() to evict_inode()
  writeback: Refactor writeback_single_inode()
  writeback: Remove wb->list_lock from writeback_single_inode()
  writeback: Separate inode requeueing after writeback
  writeback: Move I_DIRTY_PAGES handling
  writeback: Move requeueing when I_SYNC set to writeback_sb_inodes()
  writeback: Move clearing of I_SYNC into inode_sync_complete()
  writeback: initialize global_dirty_limit
  fs: remove 8 bytes of padding from struct writeback_control on 64 bit builds
  mm: page-writeback.c: local functions should not be exposed globally

Documentation/filesystems/porting

@@ -297,7 +297,8 @@ in the beginning of ->setattr unconditionally.
 be used instead.  It gets called whenever the inode is evicted, whether it has
 remaining links or not.  Caller does *not* evict the pagecache or inode-associated
 metadata buffers; getting rid of those is responsibility of method, as it had
-been for ->delete_inode().
+been for ->delete_inode(). Caller makes sure async writeback cannot be running
+for the inode while (or after) ->evict_inode() is called.
 
 	->drop_inode() returns int now; it's called on final iput() with
 inode->i_lock held and it returns true if filesystems wants the inode to be
@@ -306,14 +307,11 @@ updated appropriately.  generic_delete_inode() is also alive and it consists
 simply of return 1.  Note that all actual eviction work is done by caller after
 ->drop_inode() returns.
 
-	clear_inode() is gone; use end_writeback() instead.  As before, it must
-be called exactly once on each call of ->evict_inode() (as it used to be for
-each call of ->delete_inode()).  Unlike before, if you are using inode-associated
-metadata buffers (i.e. mark_buffer_dirty_inode()), it's your responsibility to
-call invalidate_inode_buffers() before end_writeback().
-	No async writeback (and thus no calls of ->write_inode()) will happen
-after end_writeback() returns, so actions that should not overlap with ->write_inode()
-(e.g. freeing on-disk inode if i_nlink is 0) ought to be done after that call.
+	As before, clear_inode() must be called exactly once on each call of
+->evict_inode() (as it used to be for each call of ->delete_inode()).  Unlike
+before, if you are using inode-associated metadata buffers (i.e.
+mark_buffer_dirty_inode()), it's your responsibility to call
+invalidate_inode_buffers() before clear_inode().
 
 	NOTE: checking i_nlink in the beginning of ->write_inode() and bailing out
 if it's zero is not *and* *never* *had* *been* enough.  Final unlink() and iput()

arch/powerpc/platforms/cell/spufs/inode.c

@@ -151,7 +151,7 @@ static void
 spufs_evict_inode(struct inode *inode)
 {
 	struct spufs_inode_info *ei = SPUFS_I(inode);
-	end_writeback(inode);
+	clear_inode(inode);
 	if (ei->i_ctx)
 		put_spu_context(ei->i_ctx);
 	if (ei->i_gang)

arch/s390/hypfs/inode.c

@@ -115,7 +115,7 @@ static struct inode *hypfs_make_inode(struct super_block *sb, umode_t mode)
 
 static void hypfs_evict_inode(struct inode *inode)
 {
-	end_writeback(inode);
+	clear_inode(inode);
 	kfree(inode->i_private);
 }
 

fs/9p/vfs_inode.c

@@ -448,7 +448,7 @@ void v9fs_evict_inode(struct inode *inode)
 	struct v9fs_inode *v9inode = V9FS_I(inode);
 
 	truncate_inode_pages(inode->i_mapping, 0);
-	end_writeback(inode);
+	clear_inode(inode);
 	filemap_fdatawrite(inode->i_mapping);
 
 #ifdef CONFIG_9P_FSCACHE

fs/affs/inode.c

@@ -264,7 +264,7 @@ affs_evict_inode(struct inode *inode)
 	}
 
 	invalidate_inode_buffers(inode);
-	end_writeback(inode);
+	clear_inode(inode);
 	affs_free_prealloc(inode);
 	cache_page = (unsigned long)AFFS_I(inode)->i_lc;
 	if (cache_page) {

fs/afs/inode.c

@@ -423,7 +423,7 @@ void afs_evict_inode(struct inode *inode)
 	ASSERTCMP(inode->i_ino, ==, vnode->fid.vnode);
 
 	truncate_inode_pages(&inode->i_data, 0);
-	end_writeback(inode);
+	clear_inode(inode);
 
 	afs_give_up_callback(vnode);
 

fs/autofs4/inode.c

@@ -100,7 +100,7 @@ static int autofs4_show_options(struct seq_file *m, struct dentry *root)
 
 static void autofs4_evict_inode(struct inode *inode)
 {
-	end_writeback(inode);
+	clear_inode(inode);
 	kfree(inode->i_private);
 }
 

fs/bfs/inode.c

@@ -174,7 +174,7 @@ static void bfs_evict_inode(struct inode *inode)
 
 	truncate_inode_pages(&inode->i_data, 0);
 	invalidate_inode_buffers(inode);
-	end_writeback(inode);
+	clear_inode(inode);
 
 	if (inode->i_nlink)
 		return;

fs/binfmt_misc.c

@@ -505,7 +505,7 @@ static struct inode *bm_get_inode(struct super_block *sb, int mode)
 
 static void bm_evict_inode(struct inode *inode)
 {
-	end_writeback(inode);
+	clear_inode(inode);
 	kfree(inode->i_private);
 }
 

fs/block_dev.c

@@ -487,7 +487,7 @@ static void bdev_evict_inode(struct inode *inode)
 	struct list_head *p;
 	truncate_inode_pages(&inode->i_data, 0);
 	invalidate_inode_buffers(inode); /* is it needed here? */
-	end_writeback(inode);
+	clear_inode(inode);
 	spin_lock(&bdev_lock);
 	while ( (p = bdev->bd_inodes.next) != &bdev->bd_inodes ) {
 		__bd_forget(list_entry(p, struct inode, i_devices));

fs/btrfs/inode.c

@@ -3756,7 +3756,7 @@ void btrfs_evict_inode(struct inode *inode)
 	btrfs_end_transaction(trans, root);
 	btrfs_btree_balance_dirty(root, nr);
 no_delete:
-	end_writeback(inode);
+	clear_inode(inode);
 	return;
 }
 

fs/cifs/cifsfs.c

@@ -272,7 +272,7 @@ static void
 cifs_evict_inode(struct inode *inode)
 {
 	truncate_inode_pages(&inode->i_data, 0);
-	end_writeback(inode);
+	clear_inode(inode);
 	cifs_fscache_release_inode_cookie(inode);
 }
 

fs/coda/inode.c

@@ -244,7 +244,7 @@ static void coda_put_super(struct super_block *sb)
 static void coda_evict_inode(struct inode *inode)
 {
 	truncate_inode_pages(&inode->i_data, 0);
-	end_writeback(inode);
+	clear_inode(inode);
 	coda_cache_clear_inode(inode);
 }
 

fs/ecryptfs/super.c

@@ -133,7 +133,7 @@ static int ecryptfs_statfs(struct dentry *dentry, struct kstatfs *buf)
 static void ecryptfs_evict_inode(struct inode *inode)
 {
 	truncate_inode_pages(&inode->i_data, 0);
-	end_writeback(inode);
+	clear_inode(inode);
 	iput(ecryptfs_inode_to_lower(inode));
 }
 

fs/exofs/inode.c

@@ -1473,7 +1473,7 @@ void exofs_evict_inode(struct inode *inode)
 		goto no_delete;
 
 	inode->i_size = 0;
-	end_writeback(inode);
+	clear_inode(inode);
 
 	/* if we are deleting an obj that hasn't been created yet, wait.
 	 * This also makes sure that create_done cannot be called with an
@@ -1503,5 +1503,5 @@ void exofs_evict_inode(struct inode *inode)
 	return;
 
 no_delete:
-	end_writeback(inode);
+	clear_inode(inode);
 }

fs/ext2/inode.c

@@ -90,7 +90,7 @@ void ext2_evict_inode(struct inode * inode)
 	}
 
 	invalidate_inode_buffers(inode);
-	end_writeback(inode);
+	clear_inode(inode);
 
 	ext2_discard_reservation(inode);
 	rsv = EXT2_I(inode)->i_block_alloc_info;

fs/ext3/inode.c

@@ -272,18 +272,18 @@ void ext3_evict_inode (struct inode *inode)
 	if (ext3_mark_inode_dirty(handle, inode)) {
 		/* If that failed, just dquot_drop() and be done with that */
 		dquot_drop(inode);
-		end_writeback(inode);
+		clear_inode(inode);
 	} else {
 		ext3_xattr_delete_inode(handle, inode);
 		dquot_free_inode(inode);
 		dquot_drop(inode);
-		end_writeback(inode);
+		clear_inode(inode);
 		ext3_free_inode(handle, inode);
 	}
 	ext3_journal_stop(handle);
 	return;
 no_delete:
-	end_writeback(inode);
+	clear_inode(inode);
 	dquot_drop(inode);
 }
 

fs/ext4/super.c

@@ -1007,7 +1007,7 @@ static void destroy_inodecache(void)
 void ext4_clear_inode(struct inode *inode)
 {
 	invalidate_inode_buffers(inode);
-	end_writeback(inode);
+	clear_inode(inode);
 	dquot_drop(inode);
 	ext4_discard_preallocations(inode);
 	if (EXT4_I(inode)->jinode) {

fs/fat/inode.c

@@ -454,7 +454,7 @@ static void fat_evict_inode(struct inode *inode)
 		fat_truncate_blocks(inode, 0);
 	}
 	invalidate_inode_buffers(inode);
-	end_writeback(inode);
+	clear_inode(inode);
 	fat_cache_inval_inode(inode);
 	fat_detach(inode);
 }

fs/freevxfs/vxfs_inode.c

@@ -355,6 +355,6 @@ void
 vxfs_evict_inode(struct inode *ip)
 {
 	truncate_inode_pages(&ip->i_data, 0);
-	end_writeback(ip);
+	clear_inode(ip);
 	call_rcu(&ip->i_rcu, vxfs_i_callback);
 }