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

Pull vfs updates from Al Viro:
 "In this one:

   - d_move fixes (Eric Biederman)

   - UFS fixes (me; locking is mostly sane now, a bunch of bugs in error
     handling ought to be fixed)

   - switch of sb_writers to percpu rwsem (Oleg Nesterov)

   - superblock scalability (Josef Bacik and Dave Chinner)

   - swapon(2) race fix (Hugh Dickins)"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (65 commits)
  vfs: Test for and handle paths that are unreachable from their mnt_root
  dcache: Reduce the scope of i_lock in d_splice_alias
  dcache: Handle escaped paths in prepend_path
  mm: fix potential data race in SyS_swapon
  inode: don't softlockup when evicting inodes
  inode: rename i_wb_list to i_io_list
  sync: serialise per-superblock sync operations
  inode: convert inode_sb_list_lock to per-sb
  inode: add hlist_fake to avoid the inode hash lock in evict
  writeback: plug writeback at a high level
  change sb_writers to use percpu_rw_semaphore
  shift percpu_counter_destroy() into destroy_super_work()
  percpu-rwsem: kill CONFIG_PERCPU_RWSEM
  percpu-rwsem: introduce percpu_rwsem_release() and percpu_rwsem_acquire()
  percpu-rwsem: introduce percpu_down_read_trylock()
  document rwsem_release() in sb_wait_write()
  fix the broken lockdep logic in __sb_start_write()
  introduce __sb_writers_{acquired,release}() helpers
  ufs_inode_get{frag,block}(): get rid of 'phys' argument
  ufs_getfrag_block(): tidy up a bit
  ...

arch/Kconfig

@@ -93,7 +93,6 @@ config KPROBES_ON_FTRACE
 
 config UPROBES
 	def_bool n
-	select PERCPU_RWSEM
 	help
 	  Uprobes is the user-space counterpart to kprobes: they
 	  enable instrumentation applications (such as 'perf probe')

fs/block_dev.c

@@ -1769,7 +1769,7 @@ void iterate_bdevs(void (*func)(struct block_device *, void *), void *arg)
 {
 	struct inode *inode, *old_inode = NULL;
 
-	spin_lock(&inode_sb_list_lock);
+	spin_lock(&blockdev_superblock->s_inode_list_lock);
 	list_for_each_entry(inode, &blockdev_superblock->s_inodes, i_sb_list) {
 		struct address_space *mapping = inode->i_mapping;
 
@@ -1781,13 +1781,13 @@ void iterate_bdevs(void (*func)(struct block_device *, void *), void *arg)
 		}
 		__iget(inode);
 		spin_unlock(&inode->i_lock);
-		spin_unlock(&inode_sb_list_lock);
+		spin_unlock(&blockdev_superblock->s_inode_list_lock);
 		/*
 		 * We hold a reference to 'inode' so it couldn't have been
 		 * removed from s_inodes list while we dropped the
-		 * inode_sb_list_lock.  We cannot iput the inode now as we can
+		 * s_inode_list_lock  We cannot iput the inode now as we can
 		 * be holding the last reference and we cannot iput it under
-		 * inode_sb_list_lock. So we keep the reference and iput it
+		 * s_inode_list_lock. So we keep the reference and iput it
 		 * later.
 		 */
 		iput(old_inode);
@@ -1795,8 +1795,8 @@ void iterate_bdevs(void (*func)(struct block_device *, void *), void *arg)
 
 		func(I_BDEV(inode), arg);
 
-		spin_lock(&inode_sb_list_lock);
+		spin_lock(&blockdev_superblock->s_inode_list_lock);
 	}
-	spin_unlock(&inode_sb_list_lock);
+	spin_unlock(&blockdev_superblock->s_inode_list_lock);
 	iput(old_inode);
 }

fs/btrfs/transaction.c

@@ -1640,9 +1640,7 @@ static void do_async_commit(struct work_struct *work)
 	 * Tell lockdep about it.
 	 */
 	if (ac->newtrans->type & __TRANS_FREEZABLE)
-		rwsem_acquire_read(
-		     &ac->root->fs_info->sb->s_writers.lock_map[SB_FREEZE_FS-1],
-		     0, 1, _THIS_IP_);
+		__sb_writers_acquired(ac->root->fs_info->sb, SB_FREEZE_FS);
 
 	current->journal_info = ac->newtrans;
 
@@ -1681,9 +1679,7 @@ int btrfs_commit_transaction_async(struct btrfs_trans_handle *trans,
 	 * async commit thread will be the one to unlock it.
 	 */
 	if (ac->newtrans->type & __TRANS_FREEZABLE)
-		rwsem_release(
-			&root->fs_info->sb->s_writers.lock_map[SB_FREEZE_FS-1],
-			1, _THIS_IP_);
+		__sb_writers_release(root->fs_info->sb, SB_FREEZE_FS);
 
 	schedule_work(&ac->work);
 

fs/dcache.c

@@ -2718,7 +2718,7 @@ struct dentry *d_ancestor(struct dentry *p1, struct dentry *p2)
  * This helper attempts to cope with remotely renamed directories
  *
  * It assumes that the caller is already holding
- * dentry->d_parent->d_inode->i_mutex, inode->i_lock and rename_lock
+ * dentry->d_parent->d_inode->i_mutex, and rename_lock
  *
  * Note: If ever the locking in lock_rename() changes, then please
  * remember to update this too...
@@ -2744,7 +2744,6 @@ static int __d_unalias(struct inode *inode,
 	__d_move(alias, dentry, false);
 	ret = 0;
 out_err:
-	spin_unlock(&inode->i_lock);
 	if (m2)
 		mutex_unlock(m2);
 	if (m1)
@@ -2790,10 +2789,11 @@ struct dentry *d_splice_alias(struct inode *inode, struct dentry *dentry)
 	if (S_ISDIR(inode->i_mode)) {
 		struct dentry *new = __d_find_any_alias(inode);
 		if (unlikely(new)) {
+			/* The reference to new ensures it remains an alias */
+			spin_unlock(&inode->i_lock);
 			write_seqlock(&rename_lock);
 			if (unlikely(d_ancestor(new, dentry))) {
 				write_sequnlock(&rename_lock);
-				spin_unlock(&inode->i_lock);
 				dput(new);
 				new = ERR_PTR(-ELOOP);
 				pr_warn_ratelimited(
@@ -2812,7 +2812,6 @@ struct dentry *d_splice_alias(struct inode *inode, struct dentry *dentry)
 			} else {
 				__d_move(new, dentry, false);
 				write_sequnlock(&rename_lock);
-				spin_unlock(&inode->i_lock);
 				security_d_instantiate(new, inode);
 			}
 			iput(inode);
@@ -2926,6 +2925,13 @@ static int prepend_path(const struct path *path,
 
 		if (dentry == vfsmnt->mnt_root || IS_ROOT(dentry)) {
 			struct mount *parent = ACCESS_ONCE(mnt->mnt_parent);
+			/* Escaped? */
+			if (dentry != vfsmnt->mnt_root) {
+				bptr = *buffer;
+				blen = *buflen;
+				error = 3;
+				break;
+			}
 			/* Global root? */
 			if (mnt != parent) {
 				dentry = ACCESS_ONCE(mnt->mnt_mountpoint);

fs/drop_caches.c

@@ -17,7 +17,7 @@ static void drop_pagecache_sb(struct super_block *sb, void *unused)
 {
 	struct inode *inode, *toput_inode = NULL;
 
-	spin_lock(&inode_sb_list_lock);
+	spin_lock(&sb->s_inode_list_lock);
 	list_for_each_entry(inode, &sb->s_inodes, i_sb_list) {
 		spin_lock(&inode->i_lock);
 		if ((inode->i_state & (I_FREEING|I_WILL_FREE|I_NEW)) ||
@@ -27,13 +27,15 @@ static void drop_pagecache_sb(struct super_block *sb, void *unused)
 		}
 		__iget(inode);
 		spin_unlock(&inode->i_lock);
-		spin_unlock(&inode_sb_list_lock);
+		spin_unlock(&sb->s_inode_list_lock);
+
 		invalidate_mapping_pages(inode->i_mapping, 0, -1);
 		iput(toput_inode);
 		toput_inode = inode;
-		spin_lock(&inode_sb_list_lock);
+
+		spin_lock(&sb->s_inode_list_lock);
 	}
-	spin_unlock(&inode_sb_list_lock);
+	spin_unlock(&sb->s_inode_list_lock);
 	iput(toput_inode);
 }
 

fs/fs-writeback.c

@@ -88,7 +88,7 @@ unsigned int dirtytime_expire_interval = 12 * 60 * 60;
 
 static inline struct inode *wb_inode(struct list_head *head)
 {
-	return list_entry(head, struct inode, i_wb_list);
+	return list_entry(head, struct inode, i_io_list);
 }
 
 /*
@@ -125,22 +125,22 @@ static void wb_io_lists_depopulated(struct bdi_writeback *wb)
 }
 
 /**
- * inode_wb_list_move_locked - move an inode onto a bdi_writeback IO list
+ * inode_io_list_move_locked - move an inode onto a bdi_writeback IO list
  * @inode: inode to be moved
  * @wb: target bdi_writeback
  * @head: one of @wb->b_{dirty|io|more_io}
  *
- * Move @inode->i_wb_list to @list of @wb and set %WB_has_dirty_io.
+ * Move @inode->i_io_list to @list of @wb and set %WB_has_dirty_io.
  * Returns %true if @inode is the first occupant of the !dirty_time IO
  * lists; otherwise, %false.
  */
-static bool inode_wb_list_move_locked(struct inode *inode,
+static bool inode_io_list_move_locked(struct inode *inode,
 				      struct bdi_writeback *wb,
 				      struct list_head *head)
 {
 	assert_spin_locked(&wb->list_lock);
 
-	list_move(&inode->i_wb_list, head);
+	list_move(&inode->i_io_list, head);
 
 	/* dirty_time doesn't count as dirty_io until expiration */
 	if (head != &wb->b_dirty_time)
@@ -151,19 +151,19 @@ static bool inode_wb_list_move_locked(struct inode *inode,
 }
 
 /**
- * inode_wb_list_del_locked - remove an inode from its bdi_writeback IO list
+ * inode_io_list_del_locked - remove an inode from its bdi_writeback IO list
  * @inode: inode to be removed
  * @wb: bdi_writeback @inode is being removed from
  *
  * Remove @inode which may be on one of @wb->b_{dirty|io|more_io} lists and
  * clear %WB_has_dirty_io if all are empty afterwards.
  */
-static void inode_wb_list_del_locked(struct inode *inode,
+static void inode_io_list_del_locked(struct inode *inode,
 				     struct bdi_writeback *wb)
 {
 	assert_spin_locked(&wb->list_lock);
 
-	list_del_init(&inode->i_wb_list);
+	list_del_init(&inode->i_io_list);
 	wb_io_lists_depopulated(wb);
 }
 
@@ -351,7 +351,7 @@ static void inode_switch_wbs_work_fn(struct work_struct *work)
 
 	/*
 	 * Once I_FREEING is visible under i_lock, the eviction path owns
-	 * the inode and we shouldn't modify ->i_wb_list.
+	 * the inode and we shouldn't modify ->i_io_list.
 	 */
 	if (unlikely(inode->i_state & I_FREEING))
 		goto skip_switch;
@@ -390,16 +390,16 @@ static void inode_switch_wbs_work_fn(struct work_struct *work)
 	 * is always correct including from ->b_dirty_time.  The transfer
 	 * preserves @inode->dirtied_when ordering.
 	 */
-	if (!list_empty(&inode->i_wb_list)) {
+	if (!list_empty(&inode->i_io_list)) {
 		struct inode *pos;
 
-		inode_wb_list_del_locked(inode, old_wb);
+		inode_io_list_del_locked(inode, old_wb);
 		inode->i_wb = new_wb;
-		list_for_each_entry(pos, &new_wb->b_dirty, i_wb_list)
+		list_for_each_entry(pos, &new_wb->b_dirty, i_io_list)
 			if (time_after_eq(inode->dirtied_when,
 					  pos->dirtied_when))
 				break;
-		inode_wb_list_move_locked(inode, new_wb, pos->i_wb_list.prev);
+		inode_io_list_move_locked(inode, new_wb, pos->i_io_list.prev);
 	} else {
 		inode->i_wb = new_wb;
 	}
@@ -961,12 +961,12 @@ void wb_start_background_writeback(struct bdi_writeback *wb)
 /*
  * Remove the inode from the writeback list it is on.
  */
-void inode_wb_list_del(struct inode *inode)
+void inode_io_list_del(struct inode *inode)
 {
 	struct bdi_writeback *wb;
 
 	wb = inode_to_wb_and_lock_list(inode);
-	inode_wb_list_del_locked(inode, wb);
+	inode_io_list_del_locked(inode, wb);
 	spin_unlock(&wb->list_lock);
 }
 
@@ -988,7 +988,7 @@ static void redirty_tail(struct inode *inode, struct bdi_writeback *wb)
 		if (time_before(inode->dirtied_when, tail->dirtied_when))
 			inode->dirtied_when = jiffies;
 	}
-	inode_wb_list_move_locked(inode, wb, &wb->b_dirty);
+	inode_io_list_move_locked(inode, wb, &wb->b_dirty);
 }
 
 /*
@@ -996,7 +996,7 @@ static void redirty_tail(struct inode *inode, struct bdi_writeback *wb)
  */
 static void requeue_io(struct inode *inode, struct bdi_writeback *wb)
 {
-	inode_wb_list_move_locked(inode, wb, &wb->b_more_io);
+	inode_io_list_move_locked(inode, wb, &wb->b_more_io);
 }
 
 static void inode_sync_complete(struct inode *inode)
@@ -1055,7 +1055,7 @@ static int move_expired_inodes(struct list_head *delaying_queue,
 		if (older_than_this &&
 		    inode_dirtied_after(inode, *older_than_this))
 			break;
-		list_move(&inode->i_wb_list, &tmp);
+		list_move(&inode->i_io_list, &tmp);
 		moved++;
 		if (flags & EXPIRE_DIRTY_ATIME)
 			set_bit(__I_DIRTY_TIME_EXPIRED, &inode->i_state);
@@ -1078,7 +1078,7 @@ static int move_expired_inodes(struct list_head *delaying_queue,
 		list_for_each_prev_safe(pos, node, &tmp) {
 			inode = wb_inode(pos);
 			if (inode->i_sb == sb)
-				list_move(&inode->i_wb_list, dispatch_queue);
+				list_move(&inode->i_io_list, dispatch_queue);
 		}
 	}
 out:
@@ -1232,10 +1232,10 @@ static void requeue_inode(struct inode *inode, struct bdi_writeback *wb,
 		redirty_tail(inode, wb);
 	} else if (inode->i_state & I_DIRTY_TIME) {
 		inode->dirtied_when = jiffies;
-		inode_wb_list_move_locked(inode, wb, &wb->b_dirty_time);
+		inode_io_list_move_locked(inode, wb, &wb->b_dirty_time);
 	} else {
 		/* The inode is clean. Remove from writeback lists. */
-		inode_wb_list_del_locked(inode, wb);
+		inode_io_list_del_locked(inode, wb);
 	}
 }
 
@@ -1378,7 +1378,7 @@ writeback_single_inode(struct inode *inode, struct bdi_writeback *wb,
 	 * touch it. See comment above for explanation.
 	 */
 	if (!(inode->i_state & I_DIRTY_ALL))
-		inode_wb_list_del_locked(inode, wb);
+		inode_io_list_del_locked(inode, wb);
 	spin_unlock(&wb->list_lock);
 	inode_sync_complete(inode);
 out:
@@ -1439,7 +1439,9 @@ static long writeback_sb_inodes(struct super_block *sb,
 	unsigned long start_time = jiffies;
 	long write_chunk;
 	long wrote = 0;  /* count both pages and inodes */
+	struct blk_plug plug;
 
+	blk_start_plug(&plug);
 	while (!list_empty(&wb->b_io)) {
 		struct inode *inode = wb_inode(wb->b_io.prev);
 
@@ -1537,6 +1539,7 @@ static long writeback_sb_inodes(struct super_block *sb,
 				break;
 		}
 	}
+	blk_finish_plug(&plug);
 	return wrote;
 }
 
@@ -2088,7 +2091,7 @@ void __mark_inode_dirty(struct inode *inode, int flags)
 			else
 				dirty_list = &wb->b_dirty_time;
 
-			wakeup_bdi = inode_wb_list_move_locked(inode, wb,
+			wakeup_bdi = inode_io_list_move_locked(inode, wb,
 							       dirty_list);
 
 			spin_unlock(&wb->list_lock);
@@ -2111,6 +2114,15 @@ void __mark_inode_dirty(struct inode *inode, int flags)
 }
 EXPORT_SYMBOL(__mark_inode_dirty);
 
+/*
+ * The @s_sync_lock is used to serialise concurrent sync operations
+ * to avoid lock contention problems with concurrent wait_sb_inodes() calls.
+ * Concurrent callers will block on the s_sync_lock rather than doing contending
+ * walks. The queueing maintains sync(2) required behaviour as all the IO that
+ * has been issued up to the time this function is enter is guaranteed to be
+ * completed by the time we have gained the lock and waited for all IO that is
+ * in progress regardless of the order callers are granted the lock.
+ */
 static void wait_sb_inodes(struct super_block *sb)
 {
 	struct inode *inode, *old_inode = NULL;
@@ -2121,7 +2133,8 @@ static void wait_sb_inodes(struct super_block *sb)
 	 */
 	WARN_ON(!rwsem_is_locked(&sb->s_umount));
 
-	spin_lock(&inode_sb_list_lock);
+	mutex_lock(&sb->s_sync_lock);
+	spin_lock(&sb->s_inode_list_lock);
 
 	/*
 	 * Data integrity sync. Must wait for all pages under writeback,
@@ -2141,14 +2154,14 @@ static void wait_sb_inodes(struct super_block *sb)
 		}
 		__iget(inode);
 		spin_unlock(&inode->i_lock);
-		spin_unlock(&inode_sb_list_lock);
+		spin_unlock(&sb->s_inode_list_lock);
 
 		/*
 		 * We hold a reference to 'inode' so it couldn't have been
 		 * removed from s_inodes list while we dropped the
-		 * inode_sb_list_lock.  We cannot iput the inode now as we can
+		 * s_inode_list_lock.  We cannot iput the inode now as we can
 		 * be holding the last reference and we cannot iput it under
-		 * inode_sb_list_lock. So we keep the reference and iput it
+		 * s_inode_list_lock. So we keep the reference and iput it
 		 * later.
 		 */
 		iput(old_inode);
@@ -2158,10 +2171,11 @@ static void wait_sb_inodes(struct super_block *sb)
 
 		cond_resched();
 
-		spin_lock(&inode_sb_list_lock);
+		spin_lock(&sb->s_inode_list_lock);
 	}
-	spin_unlock(&inode_sb_list_lock);
+	spin_unlock(&sb->s_inode_list_lock);
 	iput(old_inode);
+	mutex_unlock(&sb->s_sync_lock);
 }
 
 static void __writeback_inodes_sb_nr(struct super_block *sb, unsigned long nr,

fs/inode.c

@@ -28,16 +28,16 @@
  *   inode->i_state, inode->i_hash, __iget()
  * Inode LRU list locks protect:
  *   inode->i_sb->s_inode_lru, inode->i_lru
- * inode_sb_list_lock protects:
- *   sb->s_inodes, inode->i_sb_list
+ * inode->i_sb->s_inode_list_lock protects:
+ *   inode->i_sb->s_inodes, inode->i_sb_list
  * bdi->wb.list_lock protects:
- *   bdi->wb.b_{dirty,io,more_io,dirty_time}, inode->i_wb_list
+ *   bdi->wb.b_{dirty,io,more_io,dirty_time}, inode->i_io_list
  * inode_hash_lock protects:
  *   inode_hashtable, inode->i_hash
  *
  * Lock ordering:
  *
- * inode_sb_list_lock
+ * inode->i_sb->s_inode_list_lock
  *   inode->i_lock
  *     Inode LRU list locks
  *
@@ -45,7 +45,7 @@
  *   inode->i_lock
  *
  * inode_hash_lock
- *   inode_sb_list_lock
+ *   inode->i_sb->s_inode_list_lock
  *   inode->i_lock
  *
  * iunique_lock
@@ -57,8 +57,6 @@ static unsigned int i_hash_shift __read_mostly;
 static struct hlist_head *inode_hashtable __read_mostly;
 static __cacheline_aligned_in_smp DEFINE_SPINLOCK(inode_hash_lock);
 
-__cacheline_aligned_in_smp DEFINE_SPINLOCK(inode_sb_list_lock);
-
 /*
  * Empty aops. Can be used for the cases where the user does not
  * define any of the address_space operations.
@@ -359,7 +357,7 @@ void inode_init_once(struct inode *inode)
 	memset(inode, 0, sizeof(*inode));
 	INIT_HLIST_NODE(&inode->i_hash);
 	INIT_LIST_HEAD(&inode->i_devices);
-	INIT_LIST_HEAD(&inode->i_wb_list);
+	INIT_LIST_HEAD(&inode->i_io_list);
 	INIT_LIST_HEAD(&inode->i_lru);
 	address_space_init_once(&inode->i_data);
 	i_size_ordered_init(inode);
@@ -426,18 +424,18 @@ static void inode_lru_list_del(struct inode *inode)
  */
 void inode_sb_list_add(struct inode *inode)
 {
-	spin_lock(&inode_sb_list_lock);
+	spin_lock(&inode->i_sb->s_inode_list_lock);
 	list_add(&inode->i_sb_list, &inode->i_sb->s_inodes);
-	spin_unlock(&inode_sb_list_lock);
+	spin_unlock(&inode->i_sb->s_inode_list_lock);
 }
 EXPORT_SYMBOL_GPL(inode_sb_list_add);
 
 static inline void inode_sb_list_del(struct inode *inode)
 {
 	if (!list_empty(&inode->i_sb_list)) {
-		spin_lock(&inode_sb_list_lock);
+		spin_lock(&inode->i_sb->s_inode_list_lock);
 		list_del_init(&inode->i_sb_list);
-		spin_unlock(&inode_sb_list_lock);
+		spin_unlock(&inode->i_sb->s_inode_list_lock);
 	}
 }
 
@@ -527,8 +525,8 @@ static void evict(struct inode *inode)
 	BUG_ON(!(inode->i_state & I_FREEING));
 	BUG_ON(!list_empty(&inode->i_lru));
 
-	if (!list_empty(&inode->i_wb_list))
-		inode_wb_list_del(inode);
+	if (!list_empty(&inode->i_io_list))
+		inode_io_list_del(inode);
 
 	inode_sb_list_del(inode);
 
@@ -577,6 +575,7 @@ static void dispose_list(struct list_head *head)
 		list_del_init(&inode->i_lru);
 
 		evict(inode);
+		cond_resched();
 	}
 }
 
@@ -594,7 +593,8 @@ void evict_inodes(struct super_block *sb)
 	struct inode *inode, *next;
 	LIST_HEAD(dispose);
 
-	spin_lock(&inode_sb_list_lock);
+again:
+	spin_lock(&sb->s_inode_list_lock);
 	list_for_each_entry_safe(inode, next, &sb->s_inodes, i_sb_list) {
 		if (atomic_read(&inode->i_count))
 			continue;
@@ -609,8 +609,20 @@ void evict_inodes(struct super_block *sb)
 		inode_lru_list_del(inode);
 		spin_unlock(&inode->i_lock);
 		list_add(&inode->i_lru, &dispose);
+
+		/*
+		 * We can have a ton of inodes to evict at unmount time given
+		 * enough memory, check to see if we need to go to sleep for a
+		 * bit so we don't livelock.
+		 */
+		if (need_resched()) {
+			spin_unlock(&sb->s_inode_list_lock);
+			cond_resched();
+			dispose_list(&dispose);
+			goto again;
+		}
 	}
-	spin_unlock(&inode_sb_list_lock);
+	spin_unlock(&sb->s_inode_list_lock);
 
 	dispose_list(&dispose);
 }
@@ -631,7 +643,7 @@ int invalidate_inodes(struct super_block *sb, bool kill_dirty)
 	struct inode *inode, *next;
 	LIST_HEAD(dispose);
 
-	spin_lock(&inode_sb_list_lock);
+	spin_lock(&sb->s_inode_list_lock);
 	list_for_each_entry_safe(inode, next, &sb->s_inodes, i_sb_list) {
 		spin_lock(&inode->i_lock);
 		if (inode->i_state & (I_NEW | I_FREEING | I_WILL_FREE)) {
@@ -654,7 +666,7 @@ int invalidate_inodes(struct super_block *sb, bool kill_dirty)
 		spin_unlock(&inode->i_lock);
 		list_add(&inode->i_lru, &dispose);
 	}
-	spin_unlock(&inode_sb_list_lock);
+	spin_unlock(&sb->s_inode_list_lock);
 
 	dispose_list(&dispose);
 
@@ -890,7 +902,7 @@ struct inode *new_inode(struct super_block *sb)
 {
 	struct inode *inode;
 
-	spin_lock_prefetch(&inode_sb_list_lock);
+	spin_lock_prefetch(&sb->s_inode_list_lock);
 
 	inode = new_inode_pseudo(sb);
 	if (inode)

fs/internal.h

@@ -112,14 +112,13 @@ extern int vfs_open(const struct path *, struct file *, const struct cred *);
 /*
  * inode.c
  */
-extern spinlock_t inode_sb_list_lock;
 extern long prune_icache_sb(struct super_block *sb, struct shrink_control *sc);
 extern void inode_add_lru(struct inode *inode);
 
 /*
  * fs-writeback.c
  */
-extern void inode_wb_list_del(struct inode *inode);
+extern void inode_io_list_del(struct inode *inode);
 
 extern long get_nr_dirty_inodes(void);
 extern void evict_inodes(struct super_block *);

fs/namei.c

@@ -560,6 +560,24 @@ static int __nd_alloc_stack(struct nameidata *nd)
 	return 0;
 }
 
+/**
+ * path_connected - Verify that a path->dentry is below path->mnt.mnt_root
+ * @path: nameidate to verify
+ *
+ * Rename can sometimes move a file or directory outside of a bind
+ * mount, path_connected allows those cases to be detected.
+ */
+static bool path_connected(const struct path *path)
+{
+	struct vfsmount *mnt = path->mnt;
+
+	/* Only bind mounts can have disconnected paths */
+	if (mnt->mnt_root == mnt->mnt_sb->s_root)
+		return true;
+
+	return is_subdir(path->dentry, mnt->mnt_root);
+}
+
 static inline int nd_alloc_stack(struct nameidata *nd)
 {
 	if (likely(nd->depth != EMBEDDED_LEVELS))
@@ -1296,6 +1314,8 @@ static int follow_dotdot_rcu(struct nameidata *nd)
 				return -ECHILD;
 			nd->path.dentry = parent;
 			nd->seq = seq;
+			if (unlikely(!path_connected(&nd->path)))
+				return -ENOENT;
 			break;
 		} else {
 			struct mount *mnt = real_mount(nd->path.mnt);
@@ -1396,7 +1416,7 @@ static void follow_mount(struct path *path)
 	}
 }
 
-static void follow_dotdot(struct nameidata *nd)
+static int follow_dotdot(struct nameidata *nd)
 {
 	if (!nd->root.mnt)
 		set_root(nd);
@@ -1412,6 +1432,8 @@ static void follow_dotdot(struct nameidata *nd)
 			/* rare case of legitimate dget_parent()... */
 			nd->path.dentry = dget_parent(nd->path.dentry);
 			dput(old);
+			if (unlikely(!path_connected(&nd->path)))
+				return -ENOENT;
 			break;
 		}
 		if (!follow_up(&nd->path))
@@ -1419,6 +1441,7 @@ static void follow_dotdot(struct nameidata *nd)
 	}
 	follow_mount(&nd->path);
 	nd->inode = nd->path.dentry->d_inode;
+	return 0;
 }
 
 /*
@@ -1634,7 +1657,7 @@ static inline int handle_dots(struct nameidata *nd, int type)
 		if (nd->flags & LOOKUP_RCU) {
 			return follow_dotdot_rcu(nd);
 		} else
-			follow_dotdot(nd);
+			return follow_dotdot(nd);
 	}
 	return 0;
 }

fs/notify/inode_mark.c

@@ -143,17 +143,17 @@ int fsnotify_add_inode_mark(struct fsnotify_mark *mark,
 
 /**
  * fsnotify_unmount_inodes - an sb is unmounting.  handle any watched inodes.
- * @list: list of inodes being unmounted (sb->s_inodes)
+ * @sb: superblock being unmounted.
  *
  * Called during unmount with no locks held, so needs to be safe against
- * concurrent modifiers. We temporarily drop inode_sb_list_lock and CAN block.
+ * concurrent modifiers. We temporarily drop sb->s_inode_list_lock and CAN block.
  */
-void fsnotify_unmount_inodes(struct list_head *list)
+void fsnotify_unmount_inodes(struct super_block *sb)
 {
 	struct inode *inode, *next_i, *need_iput = NULL;
 
-	spin_lock(&inode_sb_list_lock);
-	list_for_each_entry_safe(inode, next_i, list, i_sb_list) {
+	spin_lock(&sb->s_inode_list_lock);
+	list_for_each_entry_safe(inode, next_i, &sb->s_inodes, i_sb_list) {
 		struct inode *need_iput_tmp;
 
 		/*
@@ -189,7 +189,7 @@ void fsnotify_unmount_inodes(struct list_head *list)
 		spin_unlock(&inode->i_lock);
 
 		/* In case the dropping of a reference would nuke next_i. */
-		while (&next_i->i_sb_list != list) {
+		while (&next_i->i_sb_list != &sb->s_inodes) {
 			spin_lock(&next_i->i_lock);
 			if (!(next_i->i_state & (I_FREEING | I_WILL_FREE)) &&
 						atomic_read(&next_i->i_count)) {
@@ -204,12 +204,12 @@ void fsnotify_unmount_inodes(struct list_head *list)
 		}
 
 		/*
-		 * We can safely drop inode_sb_list_lock here because either
+		 * We can safely drop s_inode_list_lock here because either
 		 * we actually hold references on both inode and next_i or
 		 * end of list.  Also no new inodes will be added since the
 		 * umount has begun.
 		 */
-		spin_unlock(&inode_sb_list_lock);
+		spin_unlock(&sb->s_inode_list_lock);
 
 		if (need_iput_tmp)
 			iput(need_iput_tmp);
@@ -221,7 +221,7 @@ void fsnotify_unmount_inodes(struct list_head *list)
 
 		iput(inode);
 
-		spin_lock(&inode_sb_list_lock);
+		spin_lock(&sb->s_inode_list_lock);
 	}
-	spin_unlock(&inode_sb_list_lock);
+	spin_unlock(&sb->s_inode_list_lock);
 }

fs/quota/dquot.c

@@ -928,7 +928,7 @@ static void add_dquot_ref(struct super_block *sb, int type)
 	int reserved = 0;
 #endif
 
-	spin_lock(&inode_sb_list_lock);
+	spin_lock(&sb->s_inode_list_lock);
 	list_for_each_entry(inode, &sb->s_inodes, i_sb_list) {
 		spin_lock(&inode->i_lock);
 		if ((inode->i_state & (I_FREEING|I_WILL_FREE|I_NEW)) ||
@@ -939,7 +939,7 @@ static void add_dquot_ref(struct super_block *sb, int type)
 		}
 		__iget(inode);
 		spin_unlock(&inode->i_lock);
-		spin_unlock(&inode_sb_list_lock);
+		spin_unlock(&sb->s_inode_list_lock);
 
 #ifdef CONFIG_QUOTA_DEBUG
 		if (unlikely(inode_get_rsv_space(inode) > 0))
@@ -951,15 +951,15 @@ static void add_dquot_ref(struct super_block *sb, int type)
 		/*
 		 * We hold a reference to 'inode' so it couldn't have been
 		 * removed from s_inodes list while we dropped the
-		 * inode_sb_list_lock We cannot iput the inode now as we can be
+		 * s_inode_list_lock. We cannot iput the inode now as we can be
 		 * holding the last reference and we cannot iput it under
-		 * inode_sb_list_lock. So we keep the reference and iput it
+		 * s_inode_list_lock. So we keep the reference and iput it
 		 * later.
 		 */
 		old_inode = inode;
-		spin_lock(&inode_sb_list_lock);
+		spin_lock(&sb->s_inode_list_lock);
 	}
-	spin_unlock(&inode_sb_list_lock);
+	spin_unlock(&sb->s_inode_list_lock);
 	iput(old_inode);
 
 #ifdef CONFIG_QUOTA_DEBUG
@@ -1028,7 +1028,7 @@ static void remove_dquot_ref(struct super_block *sb, int type,
 	struct inode *inode;
 	int reserved = 0;
 
-	spin_lock(&inode_sb_list_lock);
+	spin_lock(&sb->s_inode_list_lock);
 	list_for_each_entry(inode, &sb->s_inodes, i_sb_list) {
 		/*
 		 *  We have to scan also I_NEW inodes because they can already
@@ -1044,7 +1044,7 @@ static void remove_dquot_ref(struct super_block *sb, int type,
 		}
 		spin_unlock(&dq_data_lock);
 	}
-	spin_unlock(&inode_sb_list_lock);
+	spin_unlock(&sb->s_inode_list_lock);
 #ifdef CONFIG_QUOTA_DEBUG
 	if (reserved) {
 		printk(KERN_WARNING "VFS (%s): Writes happened after quota"

fs/super.c

@@ -135,6 +135,24 @@ static unsigned long super_cache_count(struct shrinker *shrink,
 	return total_objects;
 }
 
+static void destroy_super_work(struct work_struct *work)
+{
+	struct super_block *s = container_of(work, struct super_block,
+							destroy_work);
+	int i;
+
+	for (i = 0; i < SB_FREEZE_LEVELS; i++)
+		percpu_free_rwsem(&s->s_writers.rw_sem[i]);
+	kfree(s);
+}
+
+static void destroy_super_rcu(struct rcu_head *head)
+{
+	struct super_block *s = container_of(head, struct super_block, rcu);
+	INIT_WORK(&s->destroy_work, destroy_super_work);
+	schedule_work(&s->destroy_work);
+}
+
 /**
  *	destroy_super	-	frees a superblock
  *	@s: superblock to free
@@ -143,16 +161,13 @@ static unsigned long super_cache_count(struct shrinker *shrink,
  */
 static void destroy_super(struct super_block *s)
 {
-	int i;
 	list_lru_destroy(&s->s_dentry_lru);
 	list_lru_destroy(&s->s_inode_lru);
-	for (i = 0; i < SB_FREEZE_LEVELS; i++)
-		percpu_counter_destroy(&s->s_writers.counter[i]);
 	security_sb_free(s);
 	WARN_ON(!list_empty(&s->s_mounts));
 	kfree(s->s_subtype);
 	kfree(s->s_options);
-	kfree_rcu(s, rcu);
+	call_rcu(&s->rcu, destroy_super_rcu);
 }
 
 /**
@@ -178,19 +193,19 @@ static struct super_block *alloc_super(struct file_system_type *type, int flags)
 		goto fail;
 
 	for (i = 0; i < SB_FREEZE_LEVELS; i++) {
-		if (percpu_counter_init(&s->s_writers.counter[i], 0,
-					GFP_KERNEL) < 0)
+		if (__percpu_init_rwsem(&s->s_writers.rw_sem[i],
+					sb_writers_name[i],
+					&type->s_writers_key[i]))
 			goto fail;
-		lockdep_init_map(&s->s_writers.lock_map[i], sb_writers_name[i],
-				 &type->s_writers_key[i], 0);
 	}
-	init_waitqueue_head(&s->s_writers.wait);
 	init_waitqueue_head(&s->s_writers.wait_unfrozen);
 	s->s_bdi = &noop_backing_dev_info;
 	s->s_flags = flags;
 	INIT_HLIST_NODE(&s->s_instances);
 	INIT_HLIST_BL_HEAD(&s->s_anon);
+	mutex_init(&s->s_sync_lock);
 	INIT_LIST_HEAD(&s->s_inodes);
+	spin_lock_init(&s->s_inode_list_lock);
 
 	if (list_lru_init_memcg(&s->s_dentry_lru))
 		goto fail;
@@ -399,7 +414,7 @@ void generic_shutdown_super(struct super_block *sb)
 		sync_filesystem(sb);
 		sb->s_flags &= ~MS_ACTIVE;
 
-		fsnotify_unmount_inodes(&sb->s_inodes);
+		fsnotify_unmount_inodes(sb);
 
 		evict_inodes(sb);
 
@@ -1146,72 +1161,46 @@ mount_fs(struct file_system_type *type, int flags, const char *name, void *data)
  */
 void __sb_end_write(struct super_block *sb, int level)
 {
-	percpu_counter_dec(&sb->s_writers.counter[level-1]);
-	/*
-	 * Make sure s_writers are updated before we wake up waiters in
-	 * freeze_super().
-	 */
-	smp_mb();
-	if (waitqueue_active(&sb->s_writers.wait))
-		wake_up(&sb->s_writers.wait);
-	rwsem_release(&sb->s_writers.lock_map[level-1], 1, _RET_IP_);
+	percpu_up_read(sb->s_writers.rw_sem + level-1);
 }
 EXPORT_SYMBOL(__sb_end_write);
 
-#ifdef CONFIG_LOCKDEP
-/*
- * We want lockdep to tell us about possible deadlocks with freezing but
- * it's it bit tricky to properly instrument it. Getting a freeze protection
- * works as getting a read lock but there are subtle problems. XFS for example
- * gets freeze protection on internal level twice in some cases, which is OK
- * only because we already hold a freeze protection also on higher level. Due
- * to these cases we have to tell lockdep we are doing trylock when we
- * already hold a freeze protection for a higher freeze level.
- */
-static void acquire_freeze_lock(struct super_block *sb, int level, bool trylock,
-				unsigned long ip)
-{
-	int i;
-
-	if (!trylock) {
-		for (i = 0; i < level - 1; i++)
-			if (lock_is_held(&sb->s_writers.lock_map[i])) {
-				trylock = true;
-				break;
-			}
-	}
-	rwsem_acquire_read(&sb->s_writers.lock_map[level-1], 0, trylock, ip);
-}
-#endif
-
 /*
  * This is an internal function, please use sb_start_{write,pagefault,intwrite}
  * instead.
  */
 int __sb_start_write(struct super_block *sb, int level, bool wait)
 {
-retry:
-	if (unlikely(sb->s_writers.frozen >= level)) {
-		if (!wait)
-			return 0;
-		wait_event(sb->s_writers.wait_unfrozen,
-			   sb->s_writers.frozen < level);
-	}
+	bool force_trylock = false;
+	int ret = 1;
 
 #ifdef CONFIG_LOCKDEP
-	acquire_freeze_lock(sb, level, !wait, _RET_IP_);
-#endif
-	percpu_counter_inc(&sb->s_writers.counter[level-1]);
 	/*
-	 * Make sure counter is updated before we check for frozen.
-	 * freeze_super() first sets frozen and then checks the counter.
+	 * We want lockdep to tell us about possible deadlocks with freezing
+	 * but it's it bit tricky to properly instrument it. Getting a freeze
+	 * protection works as getting a read lock but there are subtle
+	 * problems. XFS for example gets freeze protection on internal level
+	 * twice in some cases, which is OK only because we already hold a
+	 * freeze protection also on higher level. Due to these cases we have
+	 * to use wait == F (trylock mode) which must not fail.
 	 */
-	smp_mb();
-	if (unlikely(sb->s_writers.frozen >= level)) {
-		__sb_end_write(sb, level);
-		goto retry;
+	if (wait) {
+		int i;
+
+		for (i = 0; i < level - 1; i++)
+			if (percpu_rwsem_is_held(sb->s_writers.rw_sem + i)) {
+				force_trylock = true;
+				break;
 			}
-	return 1;
+	}
+#endif
+	if (wait && !force_trylock)
+		percpu_down_read(sb->s_writers.rw_sem + level-1);
+	else
+		ret = percpu_down_read_trylock(sb->s_writers.rw_sem + level-1);
+
+	WARN_ON(force_trylock & !ret);
+	return ret;
 }
 EXPORT_SYMBOL(__sb_start_write);
 
@@ -1221,37 +1210,33 @@ EXPORT_SYMBOL(__sb_start_write);
  * @level: type of writers we wait for (normal vs page fault)
  *
  * This function waits until there are no writers of given type to given file
- * system. Caller of this function should make sure there can be no new writers
- * of type @level before calling this function. Otherwise this function can
- * livelock.
+ * system.
  */
 static void sb_wait_write(struct super_block *sb, int level)
 {
-	s64 writers;
-
+	percpu_down_write(sb->s_writers.rw_sem + level-1);
 	/*
-	 * We just cycle-through lockdep here so that it does not complain
-	 * about returning with lock to userspace
+	 * We are going to return to userspace and forget about this lock, the
+	 * ownership goes to the caller of thaw_super() which does unlock.
+	 *
+	 * FIXME: we should do this before return from freeze_super() after we
+	 * called sync_filesystem(sb) and s_op->freeze_fs(sb), and thaw_super()
+	 * should re-acquire these locks before s_op->unfreeze_fs(sb). However
+	 * this leads to lockdep false-positives, so currently we do the early
+	 * release right after acquire.
 	 */
-	rwsem_acquire(&sb->s_writers.lock_map[level-1], 0, 0, _THIS_IP_);
-	rwsem_release(&sb->s_writers.lock_map[level-1], 1, _THIS_IP_);
-
-	do {
-		DEFINE_WAIT(wait);
+	percpu_rwsem_release(sb->s_writers.rw_sem + level-1, 0, _THIS_IP_);
+}
 
-		/*
-		 * We use a barrier in prepare_to_wait() to separate setting
-		 * of frozen and checking of the counter
-		 */
-		prepare_to_wait(&sb->s_writers.wait, &wait,
-				TASK_UNINTERRUPTIBLE);
+static void sb_freeze_unlock(struct super_block *sb)
+{
+	int level;
 
-		writers = percpu_counter_sum(&sb->s_writers.counter[level-1]);
-		if (writers)
-			schedule();
+	for (level = 0; level < SB_FREEZE_LEVELS; ++level)
+		percpu_rwsem_acquire(sb->s_writers.rw_sem + level, 0, _THIS_IP_);
 
-		finish_wait(&sb->s_writers.wait, &wait);
-	} while (writers);
+	for (level = SB_FREEZE_LEVELS - 1; level >= 0; level--)
+		percpu_up_write(sb->s_writers.rw_sem + level);
 }
 
 /**
@@ -1310,20 +1295,14 @@ int freeze_super(struct super_block *sb)
 		return 0;
 	}
 
-	/* From now on, no new normal writers can start */
 	sb->s_writers.frozen = SB_FREEZE_WRITE;
-	smp_wmb();
-
 	/* Release s_umount to preserve sb_start_write -> s_umount ordering */
 	up_write(&sb->s_umount);
-
 	sb_wait_write(sb, SB_FREEZE_WRITE);
+	down_write(&sb->s_umount);
 
 	/* Now we go and block page faults... */
-	down_write(&sb->s_umount);
 	sb->s_writers.frozen = SB_FREEZE_PAGEFAULT;
-	smp_wmb();
-
 	sb_wait_write(sb, SB_FREEZE_PAGEFAULT);
 
 	/* All writers are done so after syncing there won't be dirty data */
@@ -1331,7 +1310,6 @@ int freeze_super(struct super_block *sb)
 
 	/* Now wait for internal filesystem counter */
 	sb->s_writers.frozen = SB_FREEZE_FS;
-	smp_wmb();
 	sb_wait_write(sb, SB_FREEZE_FS);
 
 	if (sb->s_op->freeze_fs) {
@@ -1340,7 +1318,7 @@ int freeze_super(struct super_block *sb)
 			printk(KERN_ERR
 				"VFS:Filesystem freeze failed\n");
 			sb->s_writers.frozen = SB_UNFROZEN;
-			smp_wmb();
+			sb_freeze_unlock(sb);
 			wake_up(&sb->s_writers.wait_unfrozen);
 			deactivate_locked_super(sb);
 			return ret;
@@ -1372,8 +1350,10 @@ int thaw_super(struct super_block *sb)
 		return -EINVAL;
 	}
 
-	if (sb->s_flags & MS_RDONLY)
+	if (sb->s_flags & MS_RDONLY) {
+		sb->s_writers.frozen = SB_UNFROZEN;
 		goto out;
+	}
 
 	if (sb->s_op->unfreeze_fs) {
 		error = sb->s_op->unfreeze_fs(sb);
@@ -1385,12 +1365,11 @@ int thaw_super(struct super_block *sb)
 		}
 	}
 
-out:
 	sb->s_writers.frozen = SB_UNFROZEN;
-	smp_wmb();
+	sb_freeze_unlock(sb);
+out:
 	wake_up(&sb->s_writers.wait_unfrozen);
 	deactivate_locked_super(sb);
-
 	return 0;
 }
 EXPORT_SYMBOL(thaw_super);

fs/ufs/Makefile

@@ -5,5 +5,5 @@
 obj-$(CONFIG_UFS_FS) += ufs.o
 
 ufs-objs := balloc.o cylinder.o dir.o file.o ialloc.o inode.o \
-	    namei.o super.o symlink.o truncate.o util.o
+	    namei.o super.o symlink.o util.o
 ccflags-$(CONFIG_UFS_DEBUG)    += -DDEBUG

fs/ufs/balloc.c

@@ -417,7 +417,9 @@ u64 ufs_new_fragments(struct inode *inode, void *p, u64 fragment,
 	if (oldcount == 0) {
 		result = ufs_alloc_fragments (inode, cgno, goal, count, err);
 		if (result) {
+			write_seqlock(&UFS_I(inode)->meta_lock);
 			ufs_cpu_to_data_ptr(sb, p, result);
+			write_sequnlock(&UFS_I(inode)->meta_lock);
 			*err = 0;
 			UFS_I(inode)->i_lastfrag =
 				max(UFS_I(inode)->i_lastfrag, fragment + count);
@@ -473,7 +475,9 @@ u64 ufs_new_fragments(struct inode *inode, void *p, u64 fragment,
 		ufs_change_blocknr(inode, fragment - oldcount, oldcount,
 				   uspi->s_sbbase + tmp,
 				   uspi->s_sbbase + result, locked_page);
+		write_seqlock(&UFS_I(inode)->meta_lock);
 		ufs_cpu_to_data_ptr(sb, p, result);
+		write_sequnlock(&UFS_I(inode)->meta_lock);
 		*err = 0;
 		UFS_I(inode)->i_lastfrag = max(UFS_I(inode)->i_lastfrag,
 						fragment + count);

fs/ufs/inode.c

@@ -41,9 +41,7 @@
 #include "swab.h"
 #include "util.h"
 
-static u64 ufs_frag_map(struct inode *inode, sector_t frag, bool needs_lock);
-
-static int ufs_block_to_path(struct inode *inode, sector_t i_block, sector_t offsets[4])
+static int ufs_block_to_path(struct inode *inode, sector_t i_block, unsigned offsets[4])
 {
 	struct ufs_sb_private_info *uspi = UFS_SB(inode->i_sb)->s_uspi;
 	int ptrs = uspi->s_apb;
@@ -75,227 +73,232 @@ static int ufs_block_to_path(struct inode *inode, sector_t i_block, sector_t off
 	return n;
 }
 
+typedef struct {
+	void	*p;
+	union {
+		__fs32	key32;
+		__fs64	key64;
+	};
+	struct buffer_head *bh;
+} Indirect;
+
+static inline int grow_chain32(struct ufs_inode_info *ufsi,
+			       struct buffer_head *bh, __fs32 *v,
+			       Indirect *from, Indirect *to)
+{
+	Indirect *p;
+	unsigned seq;
+	to->bh = bh;
+	do {
+		seq = read_seqbegin(&ufsi->meta_lock);
+		to->key32 = *(__fs32 *)(to->p = v);
+		for (p = from; p <= to && p->key32 == *(__fs32 *)p->p; p++)
+			;
+	} while (read_seqretry(&ufsi->meta_lock, seq));
+	return (p > to);
+}
+
+static inline int grow_chain64(struct ufs_inode_info *ufsi,
+			       struct buffer_head *bh, __fs64 *v,
+			       Indirect *from, Indirect *to)
+{
+	Indirect *p;
+	unsigned seq;
+	to->bh = bh;
+	do {
+		seq = read_seqbegin(&ufsi->meta_lock);
+		to->key64 = *(__fs64 *)(to->p = v);
+		for (p = from; p <= to && p->key64 == *(__fs64 *)p->p; p++)
+			;
+	} while (read_seqretry(&ufsi->meta_lock, seq));
+	return (p > to);
+}
+
 /*
  * Returns the location of the fragment from
  * the beginning of the filesystem.
  */
 
-static u64 ufs_frag_map(struct inode *inode, sector_t frag, bool needs_lock)
+static u64 ufs_frag_map(struct inode *inode, unsigned offsets[4], int depth)
 {
 	struct ufs_inode_info *ufsi = UFS_I(inode);
 	struct super_block *sb = inode->i_sb;
 	struct ufs_sb_private_info *uspi = UFS_SB(sb)->s_uspi;
 	u64 mask = (u64) uspi->s_apbmask>>uspi->s_fpbshift;
 	int shift = uspi->s_apbshift-uspi->s_fpbshift;
-	sector_t offsets[4], *p;
-	int depth = ufs_block_to_path(inode, frag >> uspi->s_fpbshift, offsets);
-	u64  ret = 0L;
-	__fs32 block;
-	__fs64 u2_block = 0L;
+	Indirect chain[4], *q = chain;
+	unsigned *p;
 	unsigned flags = UFS_SB(sb)->s_flags;
-	u64 temp = 0L;
+	u64 res = 0;
 
-	UFSD(": frag = %llu  depth = %d\n", (unsigned long long)frag, depth);
 	UFSD(": uspi->s_fpbshift = %d ,uspi->s_apbmask = %x, mask=%llx\n",
 		uspi->s_fpbshift, uspi->s_apbmask,
 		(unsigned long long)mask);
 
 	if (depth == 0)
-		return 0;
+		goto no_block;
 
+again:
 	p = offsets;
 
-	if (needs_lock)
-		lock_ufs(sb);
 	if ((flags & UFS_TYPE_MASK) == UFS_TYPE_UFS2)
 		goto ufs2;
 
-	block = ufsi->i_u1.i_data[*p++];
-	if (!block)
-		goto out;
+	if (!grow_chain32(ufsi, NULL, &ufsi->i_u1.i_data[*p++], chain, q))
+		goto changed;
+	if (!q->key32)
+		goto no_block;
 	while (--depth) {
+		__fs32 *ptr;
 		struct buffer_head *bh;
-		sector_t n = *p++;
+		unsigned n = *p++;
 
-		bh = sb_bread(sb, uspi->s_sbbase + fs32_to_cpu(sb, block)+(n>>shift));
+		bh = sb_bread(sb, uspi->s_sbbase +
+				  fs32_to_cpu(sb, q->key32) + (n>>shift));
 		if (!bh)
-			goto out;
-		block = ((__fs32 *) bh->b_data)[n & mask];
-		brelse (bh);
-		if (!block)
-			goto out;
+			goto no_block;
+		ptr = (__fs32 *)bh->b_data + (n & mask);
+		if (!grow_chain32(ufsi, bh, ptr, chain, ++q))
+			goto changed;
+		if (!q->key32)
+			goto no_block;
 	}
-	ret = (u64) (uspi->s_sbbase + fs32_to_cpu(sb, block) + (frag & uspi->s_fpbmask));
-	goto out;
-ufs2:
-	u2_block = ufsi->i_u1.u2_i_data[*p++];
-	if (!u2_block)
-		goto out;
+	res = fs32_to_cpu(sb, q->key32);
+	goto found;
 
+ufs2:
+	if (!grow_chain64(ufsi, NULL, &ufsi->i_u1.u2_i_data[*p++], chain, q))
+		goto changed;
+	if (!q->key64)
+		goto no_block;
 
 	while (--depth) {
+		__fs64 *ptr;
 		struct buffer_head *bh;
-		sector_t n = *p++;
+		unsigned n = *p++;
 
-
-		temp = (u64)(uspi->s_sbbase) + fs64_to_cpu(sb, u2_block);
-		bh = sb_bread(sb, temp +(u64) (n>>shift));
+		bh = sb_bread(sb, uspi->s_sbbase +
+				  fs64_to_cpu(sb, q->key64) + (n>>shift));
 		if (!bh)
-			goto out;
-		u2_block = ((__fs64 *)bh->b_data)[n & mask];
-		brelse(bh);
-		if (!u2_block)
-			goto out;
+			goto no_block;
+		ptr = (__fs64 *)bh->b_data + (n & mask);
+		if (!grow_chain64(ufsi, bh, ptr, chain, ++q))
+			goto changed;
+		if (!q->key64)
+			goto no_block;
 	}
-	temp = (u64)uspi->s_sbbase + fs64_to_cpu(sb, u2_block);
-	ret = temp + (u64) (frag & uspi->s_fpbmask);
+	res = fs64_to_cpu(sb, q->key64);
+found:
+	res += uspi->s_sbbase;
+no_block:
+	while (q > chain) {
+		brelse(q->bh);
+		q--;
+	}
+	return res;
 
-out:
-	if (needs_lock)
-		unlock_ufs(sb);
-	return ret;
+changed:
+	while (q > chain) {
+		brelse(q->bh);
+		q--;
+	}
+	goto again;
+}
+
+/*
+ * Unpacking tails: we have a file with partial final block and
+ * we had been asked to extend it.  If the fragment being written
+ * is within the same block, we need to extend the tail just to cover
+ * that fragment.  Otherwise the tail is extended to full block.
+ *
+ * Note that we might need to create a _new_ tail, but that will
+ * be handled elsewhere; this is strictly for resizing old
+ * ones.
+ */
+static bool
+ufs_extend_tail(struct inode *inode, u64 writes_to,
+		  int *err, struct page *locked_page)
+{
+	struct ufs_inode_info *ufsi = UFS_I(inode);
+	struct super_block *sb = inode->i_sb;
+	struct ufs_sb_private_info *uspi = UFS_SB(sb)->s_uspi;
+	unsigned lastfrag = ufsi->i_lastfrag;	/* it's a short file, so unsigned is enough */
+	unsigned block = ufs_fragstoblks(lastfrag);
+	unsigned new_size;
+	void *p;
+	u64 tmp;
+
+	if (writes_to < (lastfrag | uspi->s_fpbmask))
+		new_size = (writes_to & uspi->s_fpbmask) + 1;
+	else
+		new_size = uspi->s_fpb;
+
+	p = ufs_get_direct_data_ptr(uspi, ufsi, block);
+	tmp = ufs_new_fragments(inode, p, lastfrag, ufs_data_ptr_to_cpu(sb, p),
+				new_size, err, locked_page);
+	return tmp != 0;
 }
 
 /**
  * ufs_inode_getfrag() - allocate new fragment(s)
  * @inode: pointer to inode
- * @fragment: number of `fragment' which hold pointer
- *   to new allocated fragment(s)
+ * @index: number of block pointer within the inode's array.
  * @new_fragment: number of new allocated fragment(s)
- * @required: how many fragment(s) we require
  * @err: we set it if something wrong
- * @phys: pointer to where we save physical number of new allocated fragments,
- *   NULL if we allocate not data(indirect blocks for example).
  * @new: we set it if we allocate new block
  * @locked_page: for ufs_new_fragments()
  */
-static struct buffer_head *
-ufs_inode_getfrag(struct inode *inode, u64 fragment,
-		  sector_t new_fragment, unsigned int required, int *err,
-		  long *phys, int *new, struct page *locked_page)
+static u64
+ufs_inode_getfrag(struct inode *inode, unsigned index,
+		  sector_t new_fragment, int *err,
+		  int *new, struct page *locked_page)
 {
 	struct ufs_inode_info *ufsi = UFS_I(inode);
 	struct super_block *sb = inode->i_sb;
 	struct ufs_sb_private_info *uspi = UFS_SB(sb)->s_uspi;
-	struct buffer_head * result;
-	unsigned blockoff, lastblockoff;
-	u64 tmp, goal, lastfrag, block, lastblock;
-	void *p, *p2;
-
-	UFSD("ENTER, ino %lu, fragment %llu, new_fragment %llu, required %u, "
-	     "metadata %d\n", inode->i_ino, (unsigned long long)fragment,
-	     (unsigned long long)new_fragment, required, !phys);
+	u64 tmp, goal, lastfrag;
+	unsigned nfrags = uspi->s_fpb;
+	void *p;
 
         /* TODO : to be done for write support
         if ( (flags & UFS_TYPE_MASK) == UFS_TYPE_UFS2)
              goto ufs2;
          */
 
-	block = ufs_fragstoblks (fragment);
-	blockoff = ufs_fragnum (fragment);
-	p = ufs_get_direct_data_ptr(uspi, ufsi, block);
-
-	goal = 0;
-
-repeat:
+	p = ufs_get_direct_data_ptr(uspi, ufsi, index);
 	tmp = ufs_data_ptr_to_cpu(sb, p);
+	if (tmp)
+		goto out;
 
 	lastfrag = ufsi->i_lastfrag;
-	if (tmp && fragment < lastfrag) {
-		if (!phys) {
-			result = sb_getblk(sb, uspi->s_sbbase + tmp + blockoff);
-			if (tmp == ufs_data_ptr_to_cpu(sb, p)) {
-				UFSD("EXIT, result %llu\n",
-				     (unsigned long long)tmp + blockoff);
-				return result;
-			}
-			brelse (result);
-			goto repeat;
-		} else {
-			*phys = uspi->s_sbbase + tmp + blockoff;
-			return NULL;
-		}
-	}
 
-	lastblock = ufs_fragstoblks (lastfrag);
-	lastblockoff = ufs_fragnum (lastfrag);
-	/*
-	 * We will extend file into new block beyond last allocated block
-	 */
-	if (lastblock < block) {
-		/*
-		 * We must reallocate last allocated block
-		 */
-		if (lastblockoff) {
-			p2 = ufs_get_direct_data_ptr(uspi, ufsi, lastblock);
-			tmp = ufs_new_fragments(inode, p2, lastfrag,
-						ufs_data_ptr_to_cpu(sb, p2),
-						uspi->s_fpb - lastblockoff,
-						err, locked_page);
-			if (!tmp) {
-				if (lastfrag != ufsi->i_lastfrag)
-					goto repeat;
-				else
-					return NULL;
-			}
-			lastfrag = ufsi->i_lastfrag;
+	/* will that be a new tail? */
+	if (new_fragment < UFS_NDIR_FRAGMENT && new_fragment >= lastfrag)
+		nfrags = (new_fragment & uspi->s_fpbmask) + 1;
 
+	goal = 0;
+	if (index) {
+		goal = ufs_data_ptr_to_cpu(sb,
+				 ufs_get_direct_data_ptr(uspi, ufsi, index - 1));
+		if (goal)
+			goal += uspi->s_fpb;
 	}
-		tmp = ufs_data_ptr_to_cpu(sb,
-					 ufs_get_direct_data_ptr(uspi, ufsi,
-								 lastblock));
-		if (tmp)
-			goal = tmp + uspi->s_fpb;
-		tmp = ufs_new_fragments (inode, p, fragment - blockoff, 
-					 goal, required + blockoff,
-					 err,
-					 phys != NULL ? locked_page : NULL);
-	} else if (lastblock == block) {
-	/*
-	 * We will extend last allocated block
-	 */
-		tmp = ufs_new_fragments(inode, p, fragment -
-					(blockoff - lastblockoff),
-					ufs_data_ptr_to_cpu(sb, p),
-					required +  (blockoff - lastblockoff),
-					err, phys != NULL ? locked_page : NULL);
-	} else /* (lastblock > block) */ {
-	/*
-	 * We will allocate new block before last allocated block
-	 */
-		if (block) {
-			tmp = ufs_data_ptr_to_cpu(sb,
-						 ufs_get_direct_data_ptr(uspi, ufsi, block - 1));
-			if (tmp)
-				goal = tmp + uspi->s_fpb;
-		}
-		tmp = ufs_new_fragments(inode, p, fragment - blockoff,
-					goal, uspi->s_fpb, err,
-					phys != NULL ? locked_page : NULL);
-	}
+	tmp = ufs_new_fragments(inode, p, ufs_blknum(new_fragment),
+				goal, uspi->s_fpb, err, locked_page);
+
 	if (!tmp) {
-		if ((!blockoff && ufs_data_ptr_to_cpu(sb, p)) ||
-		    (blockoff && lastfrag != ufsi->i_lastfrag))
-			goto repeat;
 		*err = -ENOSPC;
-		return NULL;
+		return 0;
 	}
 
-	if (!phys) {
-		result = sb_getblk(sb, uspi->s_sbbase + tmp + blockoff);
-	} else {
-		*phys = uspi->s_sbbase + tmp + blockoff;
-		result = NULL;
-		*err = 0;
+	if (new)
 		*new = 1;
-	}
-
 	inode->i_ctime = CURRENT_TIME_SEC;
 	if (IS_SYNC(inode))
 		ufs_sync_inode (inode);
 	mark_inode_dirty(inode);
-	UFSD("EXIT, result %llu\n", (unsigned long long)tmp + blockoff);
-	return result;
+out:
+	return tmp + uspi->s_sbbase;
 
      /* This part : To be implemented ....
         Required only for writing, not required for READ-ONLY.
@@ -316,95 +319,70 @@ ufs_inode_getfrag(struct inode *inode, u64 fragment,
 /**
  * ufs_inode_getblock() - allocate new block
  * @inode: pointer to inode
- * @bh: pointer to block which hold "pointer" to new allocated block
- * @fragment: number of `fragment' which hold pointer
- *   to new allocated block
+ * @ind_block: block number of the indirect block
+ * @index: number of pointer within the indirect block
  * @new_fragment: number of new allocated fragment
  *  (block will hold this fragment and also uspi->s_fpb-1)
  * @err: see ufs_inode_getfrag()
- * @phys: see ufs_inode_getfrag()
  * @new: see ufs_inode_getfrag()
  * @locked_page: see ufs_inode_getfrag()
  */
-static struct buffer_head *
-ufs_inode_getblock(struct inode *inode, struct buffer_head *bh,
-		  u64 fragment, sector_t new_fragment, int *err,
-		  long *phys, int *new, struct page *locked_page)
+static u64
+ufs_inode_getblock(struct inode *inode, u64 ind_block,
+		  unsigned index, sector_t new_fragment, int *err,
+		  int *new, struct page *locked_page)
 {
 	struct super_block *sb = inode->i_sb;
 	struct ufs_sb_private_info *uspi = UFS_SB(sb)->s_uspi;
-	struct buffer_head * result;
-	unsigned blockoff;
-	u64 tmp, goal, block;
+	int shift = uspi->s_apbshift - uspi->s_fpbshift;
+	u64 tmp = 0, goal;
+	struct buffer_head *bh;
 	void *p;
 
-	block = ufs_fragstoblks (fragment);
-	blockoff = ufs_fragnum (fragment);
-
-	UFSD("ENTER, ino %lu, fragment %llu, new_fragment %llu, metadata %d\n",
-	     inode->i_ino, (unsigned long long)fragment,
-	     (unsigned long long)new_fragment, !phys);
+	if (!ind_block)
+		return 0;
 
-	result = NULL;
-	if (!bh)
-		goto out;
-	if (!buffer_uptodate(bh)) {
-		ll_rw_block (READ, 1, &bh);
-		wait_on_buffer (bh);
-		if (!buffer_uptodate(bh))
-			goto out;
+	bh = sb_bread(sb, ind_block + (index >> shift));
+	if (unlikely(!bh)) {
+		*err = -EIO;
+		return 0;
 	}
+
+	index &= uspi->s_apbmask >> uspi->s_fpbshift;
 	if (uspi->fs_magic == UFS2_MAGIC)
-		p = (__fs64 *)bh->b_data + block;
+		p = (__fs64 *)bh->b_data + index;
 	else
-		p = (__fs32 *)bh->b_data + block;
-repeat:
+		p = (__fs32 *)bh->b_data + index;
+
 	tmp = ufs_data_ptr_to_cpu(sb, p);
-	if (tmp) {
-		if (!phys) {
-			result = sb_getblk(sb, uspi->s_sbbase + tmp + blockoff);
-			if (tmp == ufs_data_ptr_to_cpu(sb, p))
-				goto out;
-			brelse (result);
-			goto repeat;
-		} else {
-			*phys = uspi->s_sbbase + tmp + blockoff;
+	if (tmp)
 		goto out;
-		}
-	}
 
-	if (block && (uspi->fs_magic == UFS2_MAGIC ?
-		      (tmp = fs64_to_cpu(sb, ((__fs64 *)bh->b_data)[block-1])) :
-		      (tmp = fs32_to_cpu(sb, ((__fs32 *)bh->b_data)[block-1]))))
+	if (index && (uspi->fs_magic == UFS2_MAGIC ?
+		      (tmp = fs64_to_cpu(sb, ((__fs64 *)bh->b_data)[index-1])) :
+		      (tmp = fs32_to_cpu(sb, ((__fs32 *)bh->b_data)[index-1]))))
 		goal = tmp + uspi->s_fpb;
 	else
 		goal = bh->b_blocknr + uspi->s_fpb;
 	tmp = ufs_new_fragments(inode, p, ufs_blknum(new_fragment), goal,
 				uspi->s_fpb, err, locked_page);
-	if (!tmp) {
-		if (ufs_data_ptr_to_cpu(sb, p))
-			goto repeat;
+	if (!tmp)
 		goto out;
-	}		
-
 
-	if (!phys) {
-		result = sb_getblk(sb, uspi->s_sbbase + tmp + blockoff);
-	} else {
-		*phys = uspi->s_sbbase + tmp + blockoff;
+	if (new)
 		*new = 1;
-	}
 
 	mark_buffer_dirty(bh);
 	if (IS_SYNC(inode))
 		sync_dirty_buffer(bh);
 	inode->i_ctime = CURRENT_TIME_SEC;
 	mark_inode_dirty(inode);
-	UFSD("result %llu\n", (unsigned long long)tmp + blockoff);
 out:
 	brelse (bh);
 	UFSD("EXIT\n");
-	return result;
+	if (tmp)
+		tmp += uspi->s_sbbase;
+	return tmp;
 }
 
 /**
@@ -412,103 +390,64 @@ ufs_inode_getblock(struct inode *inode, struct buffer_head *bh,
  * readpage, writepage and so on
  */
 
-int ufs_getfrag_block(struct inode *inode, sector_t fragment, struct buffer_head *bh_result, int create)
+static int ufs_getfrag_block(struct inode *inode, sector_t fragment, struct buffer_head *bh_result, int create)
 {
-	struct super_block * sb = inode->i_sb;
-	struct ufs_sb_info * sbi = UFS_SB(sb);
-	struct ufs_sb_private_info * uspi = sbi->s_uspi;
-	struct buffer_head * bh;
-	int ret, err, new;
-	unsigned long ptr,phys;
+	struct super_block *sb = inode->i_sb;
+	struct ufs_sb_private_info *uspi = UFS_SB(sb)->s_uspi;
+	int err = 0, new = 0;
+	unsigned offsets[4];
+	int depth = ufs_block_to_path(inode, fragment >> uspi->s_fpbshift, offsets);
 	u64 phys64 = 0;
-	bool needs_lock = (sbi->mutex_owner != current);
+	unsigned frag = fragment & uspi->s_fpbmask;
 
 	if (!create) {
-		phys64 = ufs_frag_map(inode, fragment, needs_lock);
-		UFSD("phys64 = %llu\n", (unsigned long long)phys64);
-		if (phys64)
-			map_bh(bh_result, sb, phys64);
-		return 0;
+		phys64 = ufs_frag_map(inode, offsets, depth);
+		goto out;
 	}
 
         /* This code entered only while writing ....? */
 
-	err = -EIO;
-	new = 0;
-	ret = 0;
-	bh = NULL;
-
-	if (needs_lock)
-		lock_ufs(sb);
+	mutex_lock(&UFS_I(inode)->truncate_mutex);
 
 	UFSD("ENTER, ino %lu, fragment %llu\n", inode->i_ino, (unsigned long long)fragment);
-	if (fragment >
-	    ((UFS_NDADDR + uspi->s_apb + uspi->s_2apb + uspi->s_3apb)
-	     << uspi->s_fpbshift))
-		goto abort_too_big;
-
-	err = 0;
-	ptr = fragment;
+	if (unlikely(!depth)) {
+		ufs_warning(sb, "ufs_get_block", "block > big");
+		err = -EIO;
+		goto out;
+	}
 
-	/*
-	 * ok, these macros clean the logic up a bit and make
-	 * it much more readable:
-	 */
-#define GET_INODE_DATABLOCK(x) \
-	ufs_inode_getfrag(inode, x, fragment, 1, &err, &phys, &new,\
-			  bh_result->b_page)
-#define GET_INODE_PTR(x) \
-	ufs_inode_getfrag(inode, x, fragment, uspi->s_fpb, &err, NULL, NULL,\
-			  bh_result->b_page)
-#define GET_INDIRECT_DATABLOCK(x) \
-	ufs_inode_getblock(inode, bh, x, fragment,	\
-			  &err, &phys, &new, bh_result->b_page)
-#define GET_INDIRECT_PTR(x) \
-	ufs_inode_getblock(inode, bh, x, fragment,	\
-			  &err, NULL, NULL, NULL)
-
-	if (ptr < UFS_NDIR_FRAGMENT) {
-		bh = GET_INODE_DATABLOCK(ptr);
+	if (UFS_I(inode)->i_lastfrag < UFS_NDIR_FRAGMENT) {
+		unsigned lastfrag = UFS_I(inode)->i_lastfrag;
+		unsigned tailfrags = lastfrag & uspi->s_fpbmask;
+		if (tailfrags && fragment >= lastfrag) {
+			if (!ufs_extend_tail(inode, fragment,
+					     &err, bh_result->b_page))
 				goto out;
 		}
-	ptr -= UFS_NDIR_FRAGMENT;
-	if (ptr < (1 << (uspi->s_apbshift + uspi->s_fpbshift))) {
-		bh = GET_INODE_PTR(UFS_IND_FRAGMENT + (ptr >> uspi->s_apbshift));
-		goto get_indirect;
-	}
-	ptr -= 1 << (uspi->s_apbshift + uspi->s_fpbshift);
-	if (ptr < (1 << (uspi->s_2apbshift + uspi->s_fpbshift))) {
-		bh = GET_INODE_PTR(UFS_DIND_FRAGMENT + (ptr >> uspi->s_2apbshift));
-		goto get_double;
-	}
-	ptr -= 1 << (uspi->s_2apbshift + uspi->s_fpbshift);
-	bh = GET_INODE_PTR(UFS_TIND_FRAGMENT + (ptr >> uspi->s_3apbshift));
-	bh = GET_INDIRECT_PTR((ptr >> uspi->s_2apbshift) & uspi->s_apbmask);
-get_double:
-	bh = GET_INDIRECT_PTR((ptr >> uspi->s_apbshift) & uspi->s_apbmask);
-get_indirect:
-	bh = GET_INDIRECT_DATABLOCK(ptr & uspi->s_apbmask);
-
-#undef GET_INODE_DATABLOCK
-#undef GET_INODE_PTR
-#undef GET_INDIRECT_DATABLOCK
-#undef GET_INDIRECT_PTR
+	}
 
+	if (depth == 1) {
+		phys64 = ufs_inode_getfrag(inode, offsets[0], fragment,
+					   &err, &new, bh_result->b_page);
+	} else {
+		int i;
+		phys64 = ufs_inode_getfrag(inode, offsets[0], fragment,
+					   &err, NULL, NULL);
+		for (i = 1; i < depth - 1; i++)
+			phys64 = ufs_inode_getblock(inode, phys64, offsets[i],
+						fragment, &err, NULL, NULL);
+		phys64 = ufs_inode_getblock(inode, phys64, offsets[depth - 1],
+					fragment, &err, &new, bh_result->b_page);
+	}
 out:
-	if (err)
-		goto abort;
+	if (phys64) {
+		phys64 += frag;
+		map_bh(bh_result, sb, phys64);
 		if (new)
 			set_buffer_new(bh_result);
-	map_bh(bh_result, sb, phys);
-abort:
-	if (needs_lock)
-		unlock_ufs(sb);
-
+	}
+	mutex_unlock(&UFS_I(inode)->truncate_mutex);
 	return err;
-
-abort_too_big:
-	ufs_warning(sb, "ufs_get_block", "block > big");
-	goto abort;
 }
 
 static int ufs_writepage(struct page *page, struct writeback_control *wbc)
@@ -526,12 +465,16 @@ int ufs_prepare_chunk(struct page *page, loff_t pos, unsigned len)
 	return __block_write_begin(page, pos, len, ufs_getfrag_block);
 }
 
+static void ufs_truncate_blocks(struct inode *);
+
 static void ufs_write_failed(struct address_space *mapping, loff_t to)
 {
 	struct inode *inode = mapping->host;
 
-	if (to > inode->i_size)
+	if (to > inode->i_size) {
 		truncate_pagecache(inode, inode->i_size);
+		ufs_truncate_blocks(inode);
+	}
 }
 
 static int ufs_write_begin(struct file *file, struct address_space *mapping,
@@ -548,6 +491,18 @@ static int ufs_write_begin(struct file *file, struct address_space *mapping,
 	return ret;
 }
 
+static int ufs_write_end(struct file *file, struct address_space *mapping,
+			loff_t pos, unsigned len, unsigned copied,
+			struct page *page, void *fsdata)
+{
+	int ret;
+
+	ret = generic_write_end(file, mapping, pos, len, copied, page, fsdata);
+	if (ret < len)
+		ufs_write_failed(mapping, pos + len);
+	return ret;
+}
+
 static sector_t ufs_bmap(struct address_space *mapping, sector_t block)
 {
 	return generic_block_bmap(mapping,block,ufs_getfrag_block);
@@ -557,7 +512,7 @@ const struct address_space_operations ufs_aops = {
 	.readpage = ufs_readpage,
 	.writepage = ufs_writepage,
 	.write_begin = ufs_write_begin,
-	.write_end = generic_write_end,
+	.write_end = ufs_write_end,
 	.bmap = ufs_bmap
 };
 
@@ -867,11 +822,7 @@ static int ufs_update_inode(struct inode * inode, int do_sync)
 
 int ufs_write_inode(struct inode *inode, struct writeback_control *wbc)
 {
-	int ret;
-	lock_ufs(inode->i_sb);
-	ret = ufs_update_inode(inode, wbc->sync_mode == WB_SYNC_ALL);
-	unlock_ufs(inode->i_sb);
-	return ret;
+	return ufs_update_inode(inode, wbc->sync_mode == WB_SYNC_ALL);
 }
 
 int ufs_sync_inode (struct inode *inode)
@@ -888,24 +839,389 @@ void ufs_evict_inode(struct inode * inode)
 
 	truncate_inode_pages_final(&inode->i_data);
 	if (want_delete) {
-		loff_t old_i_size;
-		/*UFS_I(inode)->i_dtime = CURRENT_TIME;*/
-		lock_ufs(inode->i_sb);
-		mark_inode_dirty(inode);
-		ufs_update_inode(inode, IS_SYNC(inode));
-		old_i_size = inode->i_size;
 		inode->i_size = 0;
-		if (inode->i_blocks && ufs_truncate(inode, old_i_size))
-			ufs_warning(inode->i_sb, __func__, "ufs_truncate failed\n");
-		unlock_ufs(inode->i_sb);
+		if (inode->i_blocks)
+			ufs_truncate_blocks(inode);
 	}
 
 	invalidate_inode_buffers(inode);
 	clear_inode(inode);
 
-	if (want_delete) {
-		lock_ufs(inode->i_sb);
+	if (want_delete)
 		ufs_free_inode(inode);
-		unlock_ufs(inode->i_sb);
+}
+
+struct to_free {
+	struct inode *inode;
+	u64 to;
+	unsigned count;
+};
+
+static inline void free_data(struct to_free *ctx, u64 from, unsigned count)
+{
+	if (ctx->count && ctx->to != from) {
+		ufs_free_blocks(ctx->inode, ctx->to - ctx->count, ctx->count);
+		ctx->count = 0;
+	}
+	ctx->count += count;
+	ctx->to = from + count;
+}
+
+#define DIRECT_BLOCK ((inode->i_size + uspi->s_bsize - 1) >> uspi->s_bshift)
+#define DIRECT_FRAGMENT ((inode->i_size + uspi->s_fsize - 1) >> uspi->s_fshift)
+
+static void ufs_trunc_direct(struct inode *inode)
+{
+	struct ufs_inode_info *ufsi = UFS_I(inode);
+	struct super_block * sb;
+	struct ufs_sb_private_info * uspi;
+	void *p;
+	u64 frag1, frag2, frag3, frag4, block1, block2;
+	struct to_free ctx = {.inode = inode};
+	unsigned i, tmp;
+
+	UFSD("ENTER: ino %lu\n", inode->i_ino);
+
+	sb = inode->i_sb;
+	uspi = UFS_SB(sb)->s_uspi;
+
+	frag1 = DIRECT_FRAGMENT;
+	frag4 = min_t(u64, UFS_NDIR_FRAGMENT, ufsi->i_lastfrag);
+	frag2 = ((frag1 & uspi->s_fpbmask) ? ((frag1 | uspi->s_fpbmask) + 1) : frag1);
+	frag3 = frag4 & ~uspi->s_fpbmask;
+	block1 = block2 = 0;
+	if (frag2 > frag3) {
+		frag2 = frag4;
+		frag3 = frag4 = 0;
+	} else if (frag2 < frag3) {
+		block1 = ufs_fragstoblks (frag2);
+		block2 = ufs_fragstoblks (frag3);
+	}
+
+	UFSD("ino %lu, frag1 %llu, frag2 %llu, block1 %llu, block2 %llu,"
+	     " frag3 %llu, frag4 %llu\n", inode->i_ino,
+	     (unsigned long long)frag1, (unsigned long long)frag2,
+	     (unsigned long long)block1, (unsigned long long)block2,
+	     (unsigned long long)frag3, (unsigned long long)frag4);
+
+	if (frag1 >= frag2)
+		goto next1;
+
+	/*
+	 * Free first free fragments
+	 */
+	p = ufs_get_direct_data_ptr(uspi, ufsi, ufs_fragstoblks(frag1));
+	tmp = ufs_data_ptr_to_cpu(sb, p);
+	if (!tmp )
+		ufs_panic (sb, "ufs_trunc_direct", "internal error");
+	frag2 -= frag1;
+	frag1 = ufs_fragnum (frag1);
+
+	ufs_free_fragments(inode, tmp + frag1, frag2);
+
+next1:
+	/*
+	 * Free whole blocks
+	 */
+	for (i = block1 ; i < block2; i++) {
+		p = ufs_get_direct_data_ptr(uspi, ufsi, i);
+		tmp = ufs_data_ptr_to_cpu(sb, p);
+		if (!tmp)
+			continue;
+		write_seqlock(&ufsi->meta_lock);
+		ufs_data_ptr_clear(uspi, p);
+		write_sequnlock(&ufsi->meta_lock);
+
+		free_data(&ctx, tmp, uspi->s_fpb);
+	}
+
+	free_data(&ctx, 0, 0);
+
+	if (frag3 >= frag4)
+		goto next3;
+
+	/*
+	 * Free last free fragments
+	 */
+	p = ufs_get_direct_data_ptr(uspi, ufsi, ufs_fragstoblks(frag3));
+	tmp = ufs_data_ptr_to_cpu(sb, p);
+	if (!tmp )
+		ufs_panic(sb, "ufs_truncate_direct", "internal error");
+	frag4 = ufs_fragnum (frag4);
+	write_seqlock(&ufsi->meta_lock);
+	ufs_data_ptr_clear(uspi, p);
+	write_sequnlock(&ufsi->meta_lock);
+
+	ufs_free_fragments (inode, tmp, frag4);
+ next3:
+
+	UFSD("EXIT: ino %lu\n", inode->i_ino);
+}
+
+static void free_full_branch(struct inode *inode, u64 ind_block, int depth)
+{
+	struct super_block *sb = inode->i_sb;
+	struct ufs_sb_private_info *uspi = UFS_SB(sb)->s_uspi;
+	struct ufs_buffer_head *ubh = ubh_bread(sb, ind_block, uspi->s_bsize);
+	unsigned i;
+
+	if (!ubh)
+		return;
+
+	if (--depth) {
+		for (i = 0; i < uspi->s_apb; i++) {
+			void *p = ubh_get_data_ptr(uspi, ubh, i);
+			u64 block = ufs_data_ptr_to_cpu(sb, p);
+			if (block)
+				free_full_branch(inode, block, depth);
+		}
+	} else {
+		struct to_free ctx = {.inode = inode};
+
+		for (i = 0; i < uspi->s_apb; i++) {
+			void *p = ubh_get_data_ptr(uspi, ubh, i);
+			u64 block = ufs_data_ptr_to_cpu(sb, p);
+			if (block)
+				free_data(&ctx, block, uspi->s_fpb);
+		}
+		free_data(&ctx, 0, 0);
+	}
+
+	ubh_bforget(ubh);
+	ufs_free_blocks(inode, ind_block, uspi->s_fpb);
+}
+
+static void free_branch_tail(struct inode *inode, unsigned from, struct ufs_buffer_head *ubh, int depth)
+{
+	struct super_block *sb = inode->i_sb;
+	struct ufs_sb_private_info *uspi = UFS_SB(sb)->s_uspi;
+	unsigned i;
+
+	if (--depth) {
+		for (i = from; i < uspi->s_apb ; i++) {
+			void *p = ubh_get_data_ptr(uspi, ubh, i);
+			u64 block = ufs_data_ptr_to_cpu(sb, p);
+			if (block) {
+				write_seqlock(&UFS_I(inode)->meta_lock);
+				ufs_data_ptr_clear(uspi, p);
+				write_sequnlock(&UFS_I(inode)->meta_lock);
+				ubh_mark_buffer_dirty(ubh);
+				free_full_branch(inode, block, depth);
+			}
+		}
+	} else {
+		struct to_free ctx = {.inode = inode};
+
+		for (i = from; i < uspi->s_apb; i++) {
+			void *p = ubh_get_data_ptr(uspi, ubh, i);
+			u64 block = ufs_data_ptr_to_cpu(sb, p);
+			if (block) {
+				write_seqlock(&UFS_I(inode)->meta_lock);
+				ufs_data_ptr_clear(uspi, p);
+				write_sequnlock(&UFS_I(inode)->meta_lock);
+				ubh_mark_buffer_dirty(ubh);
+				free_data(&ctx, block, uspi->s_fpb);
+			}
+		}
+		free_data(&ctx, 0, 0);
+	}
+	if (IS_SYNC(inode) && ubh_buffer_dirty(ubh))
+		ubh_sync_block(ubh);
+	ubh_brelse(ubh);
+}
+
+static int ufs_alloc_lastblock(struct inode *inode, loff_t size)
+{
+	int err = 0;
+	struct super_block *sb = inode->i_sb;
+	struct address_space *mapping = inode->i_mapping;
+	struct ufs_sb_private_info *uspi = UFS_SB(sb)->s_uspi;
+	unsigned i, end;
+	sector_t lastfrag;
+	struct page *lastpage;
+	struct buffer_head *bh;
+	u64 phys64;
+
+	lastfrag = (size + uspi->s_fsize - 1) >> uspi->s_fshift;
+
+	if (!lastfrag)
+		goto out;
+
+	lastfrag--;
+
+	lastpage = ufs_get_locked_page(mapping, lastfrag >>
+				       (PAGE_CACHE_SHIFT - inode->i_blkbits));
+       if (IS_ERR(lastpage)) {
+               err = -EIO;
+               goto out;
+       }
+
+       end = lastfrag & ((1 << (PAGE_CACHE_SHIFT - inode->i_blkbits)) - 1);
+       bh = page_buffers(lastpage);
+       for (i = 0; i < end; ++i)
+               bh = bh->b_this_page;
+
+
+       err = ufs_getfrag_block(inode, lastfrag, bh, 1);
+
+       if (unlikely(err))
+	       goto out_unlock;
+
+       if (buffer_new(bh)) {
+	       clear_buffer_new(bh);
+	       unmap_underlying_metadata(bh->b_bdev,
+					 bh->b_blocknr);
+	       /*
+		* we do not zeroize fragment, because of
+		* if it maped to hole, it already contains zeroes
+		*/
+	       set_buffer_uptodate(bh);
+	       mark_buffer_dirty(bh);
+	       set_page_dirty(lastpage);
        }
+
+       if (lastfrag >= UFS_IND_FRAGMENT) {
+	       end = uspi->s_fpb - ufs_fragnum(lastfrag) - 1;
+	       phys64 = bh->b_blocknr + 1;
+	       for (i = 0; i < end; ++i) {
+		       bh = sb_getblk(sb, i + phys64);
+		       lock_buffer(bh);
+		       memset(bh->b_data, 0, sb->s_blocksize);
+		       set_buffer_uptodate(bh);
+		       mark_buffer_dirty(bh);
+		       unlock_buffer(bh);
+		       sync_dirty_buffer(bh);
+		       brelse(bh);
+	       }
+       }
+out_unlock:
+       ufs_put_locked_page(lastpage);
+out:
+       return err;
 }
+
+static void __ufs_truncate_blocks(struct inode *inode)
+{
+	struct ufs_inode_info *ufsi = UFS_I(inode);
+	struct super_block *sb = inode->i_sb;
+	struct ufs_sb_private_info *uspi = UFS_SB(sb)->s_uspi;
+	unsigned offsets[4];
+	int depth = ufs_block_to_path(inode, DIRECT_BLOCK, offsets);
+	int depth2;
+	unsigned i;
+	struct ufs_buffer_head *ubh[3];
+	void *p;
+	u64 block;
+
+	if (!depth)
+		return;
+
+	/* find the last non-zero in offsets[] */
+	for (depth2 = depth - 1; depth2; depth2--)
+		if (offsets[depth2])
+			break;
+
+	mutex_lock(&ufsi->truncate_mutex);
+	if (depth == 1) {
+		ufs_trunc_direct(inode);
+		offsets[0] = UFS_IND_BLOCK;
+	} else {
+		/* get the blocks that should be partially emptied */
+		p = ufs_get_direct_data_ptr(uspi, ufsi, offsets[0]);
+		for (i = 0; i < depth2; i++) {
+			offsets[i]++;	/* next branch is fully freed */
+			block = ufs_data_ptr_to_cpu(sb, p);
+			if (!block)
+				break;
+			ubh[i] = ubh_bread(sb, block, uspi->s_bsize);
+			if (!ubh[i]) {
+				write_seqlock(&ufsi->meta_lock);
+				ufs_data_ptr_clear(uspi, p);
+				write_sequnlock(&ufsi->meta_lock);
+				break;
+			}
+			p = ubh_get_data_ptr(uspi, ubh[i], offsets[i + 1]);
+		}
+		while (i--)
+			free_branch_tail(inode, offsets[i + 1], ubh[i], depth - i - 1);
+	}
+	for (i = offsets[0]; i <= UFS_TIND_BLOCK; i++) {
+		p = ufs_get_direct_data_ptr(uspi, ufsi, i);
+		block = ufs_data_ptr_to_cpu(sb, p);
+		if (block) {
+			write_seqlock(&ufsi->meta_lock);
+			ufs_data_ptr_clear(uspi, p);
+			write_sequnlock(&ufsi->meta_lock);
+			free_full_branch(inode, block, i - UFS_IND_BLOCK + 1);
+		}
+	}
+	ufsi->i_lastfrag = DIRECT_FRAGMENT;
+	mark_inode_dirty(inode);
+	mutex_unlock(&ufsi->truncate_mutex);
+}
+
+static int ufs_truncate(struct inode *inode, loff_t size)
+{
+	int err = 0;
+
+	UFSD("ENTER: ino %lu, i_size: %llu, old_i_size: %llu\n",
+	     inode->i_ino, (unsigned long long)size,
+	     (unsigned long long)i_size_read(inode));
+
+	if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
+	      S_ISLNK(inode->i_mode)))
+		return -EINVAL;
+	if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
+		return -EPERM;
+
+	err = ufs_alloc_lastblock(inode, size);
+
+	if (err)
+		goto out;
+
+	block_truncate_page(inode->i_mapping, size, ufs_getfrag_block);
+
+	truncate_setsize(inode, size);
+
+	__ufs_truncate_blocks(inode);
+	inode->i_mtime = inode->i_ctime = CURRENT_TIME_SEC;
+	mark_inode_dirty(inode);
+out:
+	UFSD("EXIT: err %d\n", err);
+	return err;
+}
+
+void ufs_truncate_blocks(struct inode *inode)
+{
+	if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
+	      S_ISLNK(inode->i_mode)))
+		return;
+	if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
+		return;
+	__ufs_truncate_blocks(inode);
+}
+
+int ufs_setattr(struct dentry *dentry, struct iattr *attr)
+{
+	struct inode *inode = d_inode(dentry);
+	unsigned int ia_valid = attr->ia_valid;
+	int error;
+
+	error = inode_change_ok(inode, attr);
+	if (error)
+		return error;
+
+	if (ia_valid & ATTR_SIZE && attr->ia_size != inode->i_size) {
+		error = ufs_truncate(inode, attr->ia_size);
+		if (error)
+			return error;
+	}
+
+	setattr_copy(inode, attr);
+	mark_inode_dirty(inode);
+	return 0;
+}
+
+const struct inode_operations ufs_file_inode_operations = {
+	.setattr = ufs_setattr,
+};

fs/ufs/super.c

@@ -94,22 +94,6 @@
 #include "swab.h"
 #include "util.h"
 
-void lock_ufs(struct super_block *sb)
-{
-	struct ufs_sb_info *sbi = UFS_SB(sb);
-
-	mutex_lock(&sbi->mutex);
-	sbi->mutex_owner = current;
-}
-
-void unlock_ufs(struct super_block *sb)
-{
-	struct ufs_sb_info *sbi = UFS_SB(sb);
-
-	sbi->mutex_owner = NULL;
-	mutex_unlock(&sbi->mutex);
-}
-
 static struct inode *ufs_nfs_get_inode(struct super_block *sb, u64 ino, u32 generation)
 {
 	struct ufs_sb_private_info *uspi = UFS_SB(sb)->s_uspi;
@@ -694,7 +678,6 @@ static int ufs_sync_fs(struct super_block *sb, int wait)
 	struct ufs_super_block_third * usb3;
 	unsigned flags;
 
-	lock_ufs(sb);
 	mutex_lock(&UFS_SB(sb)->s_lock);
 
 	UFSD("ENTER\n");
@@ -714,7 +697,6 @@ static int ufs_sync_fs(struct super_block *sb, int wait)
 
 	UFSD("EXIT\n");
 	mutex_unlock(&UFS_SB(sb)->s_lock);
-	unlock_ufs(sb);
 
 	return 0;
 }
@@ -758,7 +740,6 @@ static void ufs_put_super(struct super_block *sb)
 
 	ubh_brelse_uspi (sbi->s_uspi);
 	kfree (sbi->s_uspi);
-	mutex_destroy(&sbi->mutex);
 	kfree (sbi);
 	sb->s_fs_info = NULL;
 	UFSD("EXIT\n");
@@ -801,7 +782,6 @@ static int ufs_fill_super(struct super_block *sb, void *data, int silent)
 
 	UFSD("flag %u\n", (int)(sb->s_flags & MS_RDONLY));
 	
-	mutex_init(&sbi->mutex);
 	mutex_init(&sbi->s_lock);
 	spin_lock_init(&sbi->work_lock);
 	INIT_DELAYED_WORK(&sbi->sync_work, delayed_sync_fs);
@@ -1257,7 +1237,6 @@ static int ufs_fill_super(struct super_block *sb, void *data, int silent)
 	return 0;
 
 failed:
-	mutex_destroy(&sbi->mutex);
 	if (ubh)
 		ubh_brelse_uspi (uspi);
 	kfree (uspi);
@@ -1280,7 +1259,6 @@ static int ufs_remount (struct super_block *sb, int *mount_flags, char *data)
 	unsigned flags;
 
 	sync_filesystem(sb);
-	lock_ufs(sb);
 	mutex_lock(&UFS_SB(sb)->s_lock);
 	uspi = UFS_SB(sb)->s_uspi;
 	flags = UFS_SB(sb)->s_flags;
@@ -1296,7 +1274,6 @@ static int ufs_remount (struct super_block *sb, int *mount_flags, char *data)
 	ufs_set_opt (new_mount_opt, ONERROR_LOCK);
 	if (!ufs_parse_options (data, &new_mount_opt)) {
 		mutex_unlock(&UFS_SB(sb)->s_lock);
-		unlock_ufs(sb);
 		return -EINVAL;
 	}
 	if (!(new_mount_opt & UFS_MOUNT_UFSTYPE)) {
@@ -1304,14 +1281,12 @@ static int ufs_remount (struct super_block *sb, int *mount_flags, char *data)
 	} else if ((new_mount_opt & UFS_MOUNT_UFSTYPE) != ufstype) {
 		pr_err("ufstype can't be changed during remount\n");
 		mutex_unlock(&UFS_SB(sb)->s_lock);
-		unlock_ufs(sb);
 		return -EINVAL;
 	}
 
 	if ((*mount_flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) {
 		UFS_SB(sb)->s_mount_opt = new_mount_opt;
 		mutex_unlock(&UFS_SB(sb)->s_lock);
-		unlock_ufs(sb);
 		return 0;
 	}
 	
@@ -1335,7 +1310,6 @@ static int ufs_remount (struct super_block *sb, int *mount_flags, char *data)
 #ifndef CONFIG_UFS_FS_WRITE
 		pr_err("ufs was compiled with read-only support, can't be mounted as read-write\n");
 		mutex_unlock(&UFS_SB(sb)->s_lock);
-		unlock_ufs(sb);
 		return -EINVAL;
 #else
 		if (ufstype != UFS_MOUNT_UFSTYPE_SUN && 
@@ -1345,13 +1319,11 @@ static int ufs_remount (struct super_block *sb, int *mount_flags, char *data)
 		    ufstype != UFS_MOUNT_UFSTYPE_UFS2) {
 			pr_err("this ufstype is read-only supported\n");
 			mutex_unlock(&UFS_SB(sb)->s_lock);
-			unlock_ufs(sb);
 			return -EINVAL;
 		}
 		if (!ufs_read_cylinder_structures(sb)) {
 			pr_err("failed during remounting\n");
 			mutex_unlock(&UFS_SB(sb)->s_lock);
-			unlock_ufs(sb);
 			return -EPERM;
 		}
 		sb->s_flags &= ~MS_RDONLY;
@@ -1359,7 +1331,6 @@ static int ufs_remount (struct super_block *sb, int *mount_flags, char *data)
 	}
 	UFS_SB(sb)->s_mount_opt = new_mount_opt;
 	mutex_unlock(&UFS_SB(sb)->s_lock);
-	unlock_ufs(sb);
 	return 0;
 }
 
@@ -1391,8 +1362,7 @@ static int ufs_statfs(struct dentry *dentry, struct kstatfs *buf)
 	struct ufs_super_block_third *usb3;
 	u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
 
-	lock_ufs(sb);
-
+	mutex_lock(&UFS_SB(sb)->s_lock);
 	usb3 = ubh_get_usb_third(uspi);
 	
 	if ((flags & UFS_TYPE_MASK) == UFS_TYPE_UFS2) {
@@ -1413,7 +1383,7 @@ static int ufs_statfs(struct dentry *dentry, struct kstatfs *buf)
 	buf->f_fsid.val[0] = (u32)id;
 	buf->f_fsid.val[1] = (u32)(id >> 32);
 
-	unlock_ufs(sb);
+	mutex_unlock(&UFS_SB(sb)->s_lock);
 
 	return 0;
 }
@@ -1429,6 +1399,8 @@ static struct inode *ufs_alloc_inode(struct super_block *sb)
 		return NULL;
 
 	ei->vfs_inode.i_version = 1;
+	seqlock_init(&ei->meta_lock);
+	mutex_init(&ei->truncate_mutex);
 	return &ei->vfs_inode;
 }
 

fs/ufs/truncate.c

-/*
- *  linux/fs/ufs/truncate.c
- *
- * Copyright (C) 1998
- * Daniel Pirkl <daniel.pirkl@email.cz>
- * Charles University, Faculty of Mathematics and Physics
- *
- *  from
- *
- *  linux/fs/ext2/truncate.c
- *
- * Copyright (C) 1992, 1993, 1994, 1995
- * Remy Card (card@masi.ibp.fr)
- * Laboratoire MASI - Institut Blaise Pascal
- * Universite Pierre et Marie Curie (Paris VI)
- *
- *  from
- *
- *  linux/fs/minix/truncate.c
- *
- *  Copyright (C) 1991, 1992  Linus Torvalds
- *
- *  Big-endian to little-endian byte-swapping/bitmaps by
- *        David S. Miller (davem@caip.rutgers.edu), 1995
- */
-
-/*
- * Real random numbers for secure rm added 94/02/18
- * Idea from Pierre del Perugia <delperug@gla.ecoledoc.ibp.fr>
- */
-
-/*
- * Adoptation to use page cache and UFS2 write support by
- * Evgeniy Dushistov <dushistov@mail.ru>, 2006-2007
- */
-
-#include <linux/errno.h>
-#include <linux/fs.h>
-#include <linux/fcntl.h>
-#include <linux/time.h>
-#include <linux/stat.h>
-#include <linux/string.h>
-#include <linux/buffer_head.h>
-#include <linux/blkdev.h>
-#include <linux/sched.h>
-
-#include "ufs_fs.h"
-#include "ufs.h"
-#include "swab.h"
-#include "util.h"
-
-/*
- * Secure deletion currently doesn't work. It interacts very badly
- * with buffers shared with memory mappings, and for that reason
- * can't be done in the truncate() routines. It should instead be
- * done separately in "release()" before calling the truncate routines
- * that will release the actual file blocks.
- *
- *		Linus
- */
-
-#define DIRECT_BLOCK ((inode->i_size + uspi->s_bsize - 1) >> uspi->s_bshift)
-#define DIRECT_FRAGMENT ((inode->i_size + uspi->s_fsize - 1) >> uspi->s_fshift)
-
-
-static int ufs_trunc_direct(struct inode *inode)
-{
-	struct ufs_inode_info *ufsi = UFS_I(inode);
-	struct super_block * sb;
-	struct ufs_sb_private_info * uspi;
-	void *p;
-	u64 frag1, frag2, frag3, frag4, block1, block2;
-	unsigned frag_to_free, free_count;
-	unsigned i, tmp;
-	int retry;
-	
-	UFSD("ENTER: ino %lu\n", inode->i_ino);
-
-	sb = inode->i_sb;
-	uspi = UFS_SB(sb)->s_uspi;
-	
-	frag_to_free = 0;
-	free_count = 0;
-	retry = 0;
-	
-	frag1 = DIRECT_FRAGMENT;
-	frag4 = min_t(u64, UFS_NDIR_FRAGMENT, ufsi->i_lastfrag);
-	frag2 = ((frag1 & uspi->s_fpbmask) ? ((frag1 | uspi->s_fpbmask) + 1) : frag1);
-	frag3 = frag4 & ~uspi->s_fpbmask;
-	block1 = block2 = 0;
-	if (frag2 > frag3) {
-		frag2 = frag4;
-		frag3 = frag4 = 0;
-	} else if (frag2 < frag3) {
-		block1 = ufs_fragstoblks (frag2);
-		block2 = ufs_fragstoblks (frag3);
-	}
-
-	UFSD("ino %lu, frag1 %llu, frag2 %llu, block1 %llu, block2 %llu,"
-	     " frag3 %llu, frag4 %llu\n", inode->i_ino,
-	     (unsigned long long)frag1, (unsigned long long)frag2,
-	     (unsigned long long)block1, (unsigned long long)block2,
-	     (unsigned long long)frag3, (unsigned long long)frag4);
-
-	if (frag1 >= frag2)
-		goto next1;		
-
-	/*
-	 * Free first free fragments
-	 */
-	p = ufs_get_direct_data_ptr(uspi, ufsi, ufs_fragstoblks(frag1));
-	tmp = ufs_data_ptr_to_cpu(sb, p);
-	if (!tmp )
-		ufs_panic (sb, "ufs_trunc_direct", "internal error");
-	frag2 -= frag1;
-	frag1 = ufs_fragnum (frag1);
-
-	ufs_free_fragments(inode, tmp + frag1, frag2);
-	mark_inode_dirty(inode);
-	frag_to_free = tmp + frag1;
-
-next1:
-	/*
-	 * Free whole blocks
-	 */
-	for (i = block1 ; i < block2; i++) {
-		p = ufs_get_direct_data_ptr(uspi, ufsi, i);
-		tmp = ufs_data_ptr_to_cpu(sb, p);
-		if (!tmp)
-			continue;
-		ufs_data_ptr_clear(uspi, p);
-
-		if (free_count == 0) {
-			frag_to_free = tmp;
-			free_count = uspi->s_fpb;
-		} else if (free_count > 0 && frag_to_free == tmp - free_count)
-			free_count += uspi->s_fpb;
-		else {
-			ufs_free_blocks (inode, frag_to_free, free_count);
-			frag_to_free = tmp;
-			free_count = uspi->s_fpb;
-		}
-		mark_inode_dirty(inode);
-	}
-	
-	if (free_count > 0)
-		ufs_free_blocks (inode, frag_to_free, free_count);
-
-	if (frag3 >= frag4)
-		goto next3;
-
-	/*
-	 * Free last free fragments
-	 */
-	p = ufs_get_direct_data_ptr(uspi, ufsi, ufs_fragstoblks(frag3));
-	tmp = ufs_data_ptr_to_cpu(sb, p);
-	if (!tmp )
-		ufs_panic(sb, "ufs_truncate_direct", "internal error");
-	frag4 = ufs_fragnum (frag4);
-	ufs_data_ptr_clear(uspi, p);
-
-	ufs_free_fragments (inode, tmp, frag4);
-	mark_inode_dirty(inode);
- next3:
-
-	UFSD("EXIT: ino %lu\n", inode->i_ino);
-	return retry;
-}
-
-
-static int ufs_trunc_indirect(struct inode *inode, u64 offset, void *p)
-{
-	struct super_block * sb;
-	struct ufs_sb_private_info * uspi;
-	struct ufs_buffer_head * ind_ubh;
-	void *ind;
-	u64 tmp, indirect_block, i, frag_to_free;
-	unsigned free_count;
-	int retry;
-
-	UFSD("ENTER: ino %lu, offset %llu, p: %p\n",
-	     inode->i_ino, (unsigned long long)offset, p);
-
-	BUG_ON(!p);
-		
-	sb = inode->i_sb;
-	uspi = UFS_SB(sb)->s_uspi;
-
-	frag_to_free = 0;
-	free_count = 0;
-	retry = 0;
-	
-	tmp = ufs_data_ptr_to_cpu(sb, p);
-	if (!tmp)
-		return 0;
-	ind_ubh = ubh_bread(sb, tmp, uspi->s_bsize);
-	if (tmp != ufs_data_ptr_to_cpu(sb, p)) {
-		ubh_brelse (ind_ubh);
-		return 1;
-	}
-	if (!ind_ubh) {
-		ufs_data_ptr_clear(uspi, p);
-		return 0;
-	}
-
-	indirect_block = (DIRECT_BLOCK > offset) ? (DIRECT_BLOCK - offset) : 0;
-	for (i = indirect_block; i < uspi->s_apb; i++) {
-		ind = ubh_get_data_ptr(uspi, ind_ubh, i);
-		tmp = ufs_data_ptr_to_cpu(sb, ind);
-		if (!tmp)
-			continue;
-
-		ufs_data_ptr_clear(uspi, ind);
-		ubh_mark_buffer_dirty(ind_ubh);
-		if (free_count == 0) {
-			frag_to_free = tmp;
-			free_count = uspi->s_fpb;
-		} else if (free_count > 0 && frag_to_free == tmp - free_count)
-			free_count += uspi->s_fpb;
-		else {
-			ufs_free_blocks (inode, frag_to_free, free_count);
-			frag_to_free = tmp;
-			free_count = uspi->s_fpb;
-		}
-
-		mark_inode_dirty(inode);
-	}
-
-	if (free_count > 0) {
-		ufs_free_blocks (inode, frag_to_free, free_count);
-	}
-	for (i = 0; i < uspi->s_apb; i++)
-		if (!ufs_is_data_ptr_zero(uspi,
-					  ubh_get_data_ptr(uspi, ind_ubh, i)))
-			break;
-	if (i >= uspi->s_apb) {
-		tmp = ufs_data_ptr_to_cpu(sb, p);
-		ufs_data_ptr_clear(uspi, p);
-
-		ufs_free_blocks (inode, tmp, uspi->s_fpb);
-		mark_inode_dirty(inode);
-		ubh_bforget(ind_ubh);
-		ind_ubh = NULL;
-	}
-	if (IS_SYNC(inode) && ind_ubh && ubh_buffer_dirty(ind_ubh))
-		ubh_sync_block(ind_ubh);
-	ubh_brelse (ind_ubh);
-	
-	UFSD("EXIT: ino %lu\n", inode->i_ino);
-	
-	return retry;
-}
-
-static int ufs_trunc_dindirect(struct inode *inode, u64 offset, void *p)
-{
-	struct super_block * sb;
-	struct ufs_sb_private_info * uspi;
-	struct ufs_buffer_head *dind_bh;
-	u64 i, tmp, dindirect_block;
-	void *dind;
-	int retry = 0;
-	
-	UFSD("ENTER: ino %lu\n", inode->i_ino);
-	
-	sb = inode->i_sb;
-	uspi = UFS_SB(sb)->s_uspi;
-
-	dindirect_block = (DIRECT_BLOCK > offset) 
-		? ((DIRECT_BLOCK - offset) >> uspi->s_apbshift) : 0;
-	retry = 0;
-	
-	tmp = ufs_data_ptr_to_cpu(sb, p);
-	if (!tmp)
-		return 0;
-	dind_bh = ubh_bread(sb, tmp, uspi->s_bsize);
-	if (tmp != ufs_data_ptr_to_cpu(sb, p)) {
-		ubh_brelse (dind_bh);
-		return 1;
-	}
-	if (!dind_bh) {
-		ufs_data_ptr_clear(uspi, p);
-		return 0;
-	}
-
-	for (i = dindirect_block ; i < uspi->s_apb ; i++) {
-		dind = ubh_get_data_ptr(uspi, dind_bh, i);
-		tmp = ufs_data_ptr_to_cpu(sb, dind);
-		if (!tmp)
-			continue;
-		retry |= ufs_trunc_indirect (inode, offset + (i << uspi->s_apbshift), dind);
-		ubh_mark_buffer_dirty(dind_bh);
-	}
-
-	for (i = 0; i < uspi->s_apb; i++)
-		if (!ufs_is_data_ptr_zero(uspi,
-					  ubh_get_data_ptr(uspi, dind_bh, i)))
-			break;
-	if (i >= uspi->s_apb) {
-		tmp = ufs_data_ptr_to_cpu(sb, p);
-		ufs_data_ptr_clear(uspi, p);
-
-		ufs_free_blocks(inode, tmp, uspi->s_fpb);
-		mark_inode_dirty(inode);
-		ubh_bforget(dind_bh);
-		dind_bh = NULL;
-	}
-	if (IS_SYNC(inode) && dind_bh && ubh_buffer_dirty(dind_bh))
-		ubh_sync_block(dind_bh);
-	ubh_brelse (dind_bh);
-	
-	UFSD("EXIT: ino %lu\n", inode->i_ino);
-	
-	return retry;
-}
-
-static int ufs_trunc_tindirect(struct inode *inode)
-{
-	struct super_block *sb = inode->i_sb;
-	struct ufs_sb_private_info *uspi = UFS_SB(sb)->s_uspi;
-	struct ufs_inode_info *ufsi = UFS_I(inode);
-	struct ufs_buffer_head * tind_bh;
-	u64 tindirect_block, tmp, i;
-	void *tind, *p;
-	int retry;
-	
-	UFSD("ENTER: ino %lu\n", inode->i_ino);
-
-	retry = 0;
-	
-	tindirect_block = (DIRECT_BLOCK > (UFS_NDADDR + uspi->s_apb + uspi->s_2apb))
-		? ((DIRECT_BLOCK - UFS_NDADDR - uspi->s_apb - uspi->s_2apb) >> uspi->s_2apbshift) : 0;
-
-	p = ufs_get_direct_data_ptr(uspi, ufsi, UFS_TIND_BLOCK);
-	if (!(tmp = ufs_data_ptr_to_cpu(sb, p)))
-		return 0;
-	tind_bh = ubh_bread (sb, tmp, uspi->s_bsize);
-	if (tmp != ufs_data_ptr_to_cpu(sb, p)) {
-		ubh_brelse (tind_bh);
-		return 1;
-	}
-	if (!tind_bh) {
-		ufs_data_ptr_clear(uspi, p);
-		return 0;
-	}
-
-	for (i = tindirect_block ; i < uspi->s_apb ; i++) {
-		tind = ubh_get_data_ptr(uspi, tind_bh, i);
-		retry |= ufs_trunc_dindirect(inode, UFS_NDADDR + 
-			uspi->s_apb + ((i + 1) << uspi->s_2apbshift), tind);
-		ubh_mark_buffer_dirty(tind_bh);
-	}
-	for (i = 0; i < uspi->s_apb; i++)
-		if (!ufs_is_data_ptr_zero(uspi,
-					  ubh_get_data_ptr(uspi, tind_bh, i)))
-			break;
-	if (i >= uspi->s_apb) {
-		tmp = ufs_data_ptr_to_cpu(sb, p);
-		ufs_data_ptr_clear(uspi, p);
-
-		ufs_free_blocks(inode, tmp, uspi->s_fpb);
-		mark_inode_dirty(inode);
-		ubh_bforget(tind_bh);
-		tind_bh = NULL;
-	}
-	if (IS_SYNC(inode) && tind_bh && ubh_buffer_dirty(tind_bh))
-		ubh_sync_block(tind_bh);
-	ubh_brelse (tind_bh);
-	
-	UFSD("EXIT: ino %lu\n", inode->i_ino);
-	return retry;
-}
-
-static int ufs_alloc_lastblock(struct inode *inode)
-{
-	int err = 0;
-	struct super_block *sb = inode->i_sb;
-	struct address_space *mapping = inode->i_mapping;
-	struct ufs_sb_private_info *uspi = UFS_SB(sb)->s_uspi;
-	unsigned i, end;
-	sector_t lastfrag;
-	struct page *lastpage;
-	struct buffer_head *bh;
-	u64 phys64;
-
-	lastfrag = (i_size_read(inode) + uspi->s_fsize - 1) >> uspi->s_fshift;
-
-	if (!lastfrag)
-		goto out;
-
-	lastfrag--;
-
-	lastpage = ufs_get_locked_page(mapping, lastfrag >>
-				       (PAGE_CACHE_SHIFT - inode->i_blkbits));
-       if (IS_ERR(lastpage)) {
-               err = -EIO;
-               goto out;
-       }
-
-       end = lastfrag & ((1 << (PAGE_CACHE_SHIFT - inode->i_blkbits)) - 1);
-       bh = page_buffers(lastpage);
-       for (i = 0; i < end; ++i)
-               bh = bh->b_this_page;
-
-
-       err = ufs_getfrag_block(inode, lastfrag, bh, 1);
-
-       if (unlikely(err))
-	       goto out_unlock;
-
-       if (buffer_new(bh)) {
-	       clear_buffer_new(bh);
-	       unmap_underlying_metadata(bh->b_bdev,
-					 bh->b_blocknr);
-	       /*
-		* we do not zeroize fragment, because of
-		* if it maped to hole, it already contains zeroes
-		*/
-	       set_buffer_uptodate(bh);
-	       mark_buffer_dirty(bh);
-	       set_page_dirty(lastpage);
-       }
-
-       if (lastfrag >= UFS_IND_FRAGMENT) {
-	       end = uspi->s_fpb - ufs_fragnum(lastfrag) - 1;
-	       phys64 = bh->b_blocknr + 1;
-	       for (i = 0; i < end; ++i) {
-		       bh = sb_getblk(sb, i + phys64);
-		       lock_buffer(bh);
-		       memset(bh->b_data, 0, sb->s_blocksize);
-		       set_buffer_uptodate(bh);
-		       mark_buffer_dirty(bh);
-		       unlock_buffer(bh);
-		       sync_dirty_buffer(bh);
-		       brelse(bh);
-	       }
-       }
-out_unlock:
-       ufs_put_locked_page(lastpage);
-out:
-       return err;
-}
-
-int ufs_truncate(struct inode *inode, loff_t old_i_size)
-{
-	struct ufs_inode_info *ufsi = UFS_I(inode);
-	struct super_block *sb = inode->i_sb;
-	struct ufs_sb_private_info *uspi = UFS_SB(sb)->s_uspi;
-	int retry, err = 0;
-	
-	UFSD("ENTER: ino %lu, i_size: %llu, old_i_size: %llu\n",
-	     inode->i_ino, (unsigned long long)i_size_read(inode),
-	     (unsigned long long)old_i_size);
-
-	if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
-	      S_ISLNK(inode->i_mode)))
-		return -EINVAL;
-	if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
-		return -EPERM;
-
-	err = ufs_alloc_lastblock(inode);
-
-	if (err) {
-		i_size_write(inode, old_i_size);
-		goto out;
-	}
-
-	block_truncate_page(inode->i_mapping, inode->i_size, ufs_getfrag_block);
-
-	while (1) {
-		retry = ufs_trunc_direct(inode);
-		retry |= ufs_trunc_indirect(inode, UFS_IND_BLOCK,
-					    ufs_get_direct_data_ptr(uspi, ufsi,
-								    UFS_IND_BLOCK));
-		retry |= ufs_trunc_dindirect(inode, UFS_IND_BLOCK + uspi->s_apb,
-					     ufs_get_direct_data_ptr(uspi, ufsi,
-								     UFS_DIND_BLOCK));
-		retry |= ufs_trunc_tindirect (inode);
-		if (!retry)
-			break;
-		if (IS_SYNC(inode) && (inode->i_state & I_DIRTY))
-			ufs_sync_inode (inode);
-		yield();
-	}
-
-	inode->i_mtime = inode->i_ctime = CURRENT_TIME_SEC;
-	ufsi->i_lastfrag = DIRECT_FRAGMENT;
-	mark_inode_dirty(inode);
-out:
-	UFSD("EXIT: err %d\n", err);
-	return err;
-}
-
-int ufs_setattr(struct dentry *dentry, struct iattr *attr)
-{
-	struct inode *inode = d_inode(dentry);
-	unsigned int ia_valid = attr->ia_valid;
-	int error;
-
-	error = inode_change_ok(inode, attr);
-	if (error)
-		return error;
-
-	if (ia_valid & ATTR_SIZE && attr->ia_size != inode->i_size) {
-		loff_t old_i_size = inode->i_size;
-
-		/* XXX(truncate): truncate_setsize should be called last */
-		truncate_setsize(inode, attr->ia_size);
-
-		lock_ufs(inode->i_sb);
-		error = ufs_truncate(inode, old_i_size);
-		unlock_ufs(inode->i_sb);
-		if (error)
-			return error;
-	}
-
-	setattr_copy(inode, attr);
-	mark_inode_dirty(inode);
-	return 0;
-}
-
-const struct inode_operations ufs_file_inode_operations = {
-	.setattr = ufs_setattr,
-};

fs/ufs/ufs.h

@@ -24,8 +24,6 @@ struct ufs_sb_info {
 	unsigned s_cgno[UFS_MAX_GROUP_LOADED];
 	unsigned short s_cg_loaded;
 	unsigned s_mount_opt;
-	struct mutex mutex;
-	struct task_struct *mutex_owner;
 	struct super_block *sb;
 	int work_queued; /* non-zero if the delayed work is queued */
 	struct delayed_work sync_work; /* FS sync delayed work */
@@ -46,6 +44,8 @@ struct ufs_inode_info {
 	__u32	i_oeftflag;
 	__u16	i_osync;
 	__u64	i_lastfrag;
+	seqlock_t meta_lock;
+	struct mutex	truncate_mutex;
 	__u32   i_dir_start_lookup;
 	struct inode vfs_inode;
 };
@@ -122,7 +122,7 @@ extern struct inode *ufs_iget(struct super_block *, unsigned long);
 extern int ufs_write_inode (struct inode *, struct writeback_control *);
 extern int ufs_sync_inode (struct inode *);
 extern void ufs_evict_inode (struct inode *);
-extern int ufs_getfrag_block (struct inode *inode, sector_t fragment, struct buffer_head *bh_result, int create);
+extern int ufs_setattr(struct dentry *dentry, struct iattr *attr);
 
 /* namei.c */
 extern const struct file_operations ufs_dir_operations;
@@ -140,10 +140,6 @@ void ufs_mark_sb_dirty(struct super_block *sb);
 extern const struct inode_operations ufs_fast_symlink_inode_operations;
 extern const struct inode_operations ufs_symlink_inode_operations;
 
-/* truncate.c */
-extern int ufs_truncate (struct inode *, loff_t);
-extern int ufs_setattr(struct dentry *dentry, struct iattr *attr);
-
 static inline struct ufs_sb_info *UFS_SB(struct super_block *sb)
 {
 	return sb->s_fs_info;
@@ -170,7 +166,4 @@ static inline u32 ufs_dtogd(struct ufs_sb_private_info * uspi, u64 b)
 	return do_div(b, uspi->s_fpg);
 }
 
-extern void lock_ufs(struct super_block *sb);
-extern void unlock_ufs(struct super_block *sb);
-
 #endif /* _UFS_UFS_H */

fs/xfs/xfs_aops.c

@@ -119,8 +119,7 @@ xfs_setfilesize_trans_alloc(
 	 * We may pass freeze protection with a transaction.  So tell lockdep
 	 * we released it.
 	 */
-	rwsem_release(&ioend->io_inode->i_sb->s_writers.lock_map[SB_FREEZE_FS-1],
-		      1, _THIS_IP_);
+	__sb_writers_release(ioend->io_inode->i_sb, SB_FREEZE_FS);
 	/*
 	 * We hand off the transaction to the completion thread now, so
 	 * clear the flag here.
@@ -171,8 +170,7 @@ xfs_setfilesize_ioend(
 	 * Similarly for freeze protection.
 	 */
 	current_set_flags_nested(&tp->t_pflags, PF_FSTRANS);
-	rwsem_acquire_read(&VFS_I(ip)->i_sb->s_writers.lock_map[SB_FREEZE_FS-1],
-			   0, 1, _THIS_IP_);
+	__sb_writers_acquired(VFS_I(ip)->i_sb, SB_FREEZE_FS);
 
 	return xfs_setfilesize(ip, tp, ioend->io_offset, ioend->io_size);
 }

include/linux/fs.h

 #ifndef _LINUX_FS_H
 #define _LINUX_FS_H
 
-
 #include <linux/linkage.h>
 #include <linux/wait.h>
 #include <linux/kdev_t.h>
@@ -30,6 +29,8 @@
 #include <linux/lockdep.h>
 #include <linux/percpu-rwsem.h>
 #include <linux/blk_types.h>
+#include <linux/workqueue.h>
+#include <linux/percpu-rwsem.h>
 
 #include <asm/byteorder.h>
 #include <uapi/linux/fs.h>
@@ -636,7 +637,7 @@ struct inode {
 	unsigned long		dirtied_time_when;
 
 	struct hlist_node	i_hash;
-	struct list_head	i_wb_list;	/* backing dev IO list */
+	struct list_head	i_io_list;	/* backing dev IO list */
 #ifdef CONFIG_CGROUP_WRITEBACK
 	struct bdi_writeback	*i_wb;		/* the associated cgroup wb */
 
@@ -1281,16 +1282,9 @@ enum {
 #define SB_FREEZE_LEVELS (SB_FREEZE_COMPLETE - 1)
 
 struct sb_writers {
-	/* Counters for counting writers at each level */
-	struct percpu_counter	counter[SB_FREEZE_LEVELS];
-	wait_queue_head_t	wait;		/* queue for waiting for
-						   writers / faults to finish */
 	int				frozen;		/* Is sb frozen? */
-	wait_queue_head_t	wait_unfrozen;	/* queue for waiting for
-						   sb to be thawed */
-#ifdef CONFIG_DEBUG_LOCK_ALLOC
-	struct lockdep_map	lock_map[SB_FREEZE_LEVELS];
-#endif
+	wait_queue_head_t		wait_unfrozen;	/* for get_super_thawed() */
+	struct percpu_rw_semaphore	rw_sem[SB_FREEZE_LEVELS];
 };
 
 struct super_block {
@@ -1316,7 +1310,6 @@ struct super_block {
 #endif
 	const struct xattr_handler **s_xattr;
 
-	struct list_head	s_inodes;	/* all inodes */
 	struct hlist_bl_head	s_anon;		/* anonymous dentries for (nfs) exporting */
 	struct list_head	s_mounts;	/* list of mounts; _not_ for fs use */
 	struct block_device	*s_bdev;
@@ -1382,11 +1375,18 @@ struct super_block {
 	struct list_lru		s_dentry_lru ____cacheline_aligned_in_smp;
 	struct list_lru		s_inode_lru ____cacheline_aligned_in_smp;
 	struct rcu_head		rcu;
+	struct work_struct	destroy_work;
+
+	struct mutex		s_sync_lock;	/* sync serialisation lock */
 
 	/*
 	 * Indicates how deep in a filesystem stack this SB is
 	 */
 	int s_stack_depth;
+
+	/* s_inode_list_lock protects s_inodes */
+	spinlock_t		s_inode_list_lock ____cacheline_aligned_in_smp;
+	struct list_head	s_inodes;	/* all inodes */
 };
 
 extern struct timespec current_fs_time(struct super_block *sb);
@@ -1398,6 +1398,11 @@ extern struct timespec current_fs_time(struct super_block *sb);
 void __sb_end_write(struct super_block *sb, int level);
 int __sb_start_write(struct super_block *sb, int level, bool wait);
 
+#define __sb_writers_acquired(sb, lev)	\
+	percpu_rwsem_acquire(&(sb)->s_writers.rw_sem[(lev)-1], 1, _THIS_IP_)
+#define __sb_writers_release(sb, lev)	\
+	percpu_rwsem_release(&(sb)->s_writers.rw_sem[(lev)-1], 1, _THIS_IP_)
+
 /**
  * sb_end_write - drop write access to a superblock
  * @sb: the super we wrote to
@@ -2614,7 +2619,7 @@ static inline void insert_inode_hash(struct inode *inode)
 extern void __remove_inode_hash(struct inode *);
 static inline void remove_inode_hash(struct inode *inode)
 {
-	if (!inode_unhashed(inode))
+	if (!inode_unhashed(inode) && !hlist_fake(&inode->i_hash))
 		__remove_inode_hash(inode);
 }
 

include/linux/fsnotify_backend.h

@@ -368,7 +368,7 @@ extern void fsnotify_clear_marks_by_group_flags(struct fsnotify_group *group, un
 extern void fsnotify_clear_marks_by_group(struct fsnotify_group *group);
 extern void fsnotify_get_mark(struct fsnotify_mark *mark);
 extern void fsnotify_put_mark(struct fsnotify_mark *mark);
-extern void fsnotify_unmount_inodes(struct list_head *list);
+extern void fsnotify_unmount_inodes(struct super_block *sb);
 
 /* put here because inotify does some weird stuff when destroying watches */
 extern void fsnotify_init_event(struct fsnotify_event *event,
@@ -404,7 +404,7 @@ static inline u32 fsnotify_get_cookie(void)
 	return 0;
 }
 
-static inline void fsnotify_unmount_inodes(struct list_head *list)
+static inline void fsnotify_unmount_inodes(struct super_block *sb)
 {}
 
 #endif	/* CONFIG_FSNOTIFY */

include/linux/list.h

@@ -672,6 +672,11 @@ static inline void hlist_add_fake(struct hlist_node *n)
 	n->pprev = &n->next;
 }
 
+static inline bool hlist_fake(struct hlist_node *h)
+{
+	return h->pprev == &h->next;
+}
+
 /*
  * Move a list from one list head to another. Fixup the pprev
  * reference of the first entry if it exists.

include/linux/percpu-rwsem.h

@@ -16,6 +16,7 @@ struct percpu_rw_semaphore {
 };
 
 extern void percpu_down_read(struct percpu_rw_semaphore *);
+extern int  percpu_down_read_trylock(struct percpu_rw_semaphore *);
 extern void percpu_up_read(struct percpu_rw_semaphore *);
 
 extern void percpu_down_write(struct percpu_rw_semaphore *);
@@ -31,4 +32,23 @@ extern void percpu_free_rwsem(struct percpu_rw_semaphore *);
 	__percpu_init_rwsem(brw, #brw, &rwsem_key);		\
 })
 
+
+#define percpu_rwsem_is_held(sem) lockdep_is_held(&(sem)->rw_sem)
+
+static inline void percpu_rwsem_release(struct percpu_rw_semaphore *sem,
+					bool read, unsigned long ip)
+{
+	lock_release(&sem->rw_sem.dep_map, 1, ip);
+#ifdef CONFIG_RWSEM_SPIN_ON_OWNER
+	if (!read)
+		sem->rw_sem.owner = NULL;
+#endif
+}
+
+static inline void percpu_rwsem_acquire(struct percpu_rw_semaphore *sem,
+					bool read, unsigned long ip)
+{
+	lock_acquire(&sem->rw_sem.dep_map, 0, 1, read, 1, NULL, ip);
+}
+
 #endif

init/Kconfig

@@ -927,7 +927,6 @@ config NUMA_BALANCING_DEFAULT_ENABLED
 menuconfig CGROUPS
 	bool "Control Group support"
 	select KERNFS
-	select PERCPU_RWSEM
 	help
 	  This option adds support for grouping sets of processes together, for
 	  use with process control subsystems such as Cpusets, CFS, memory

kernel/locking/Makefile

 
-obj-y += mutex.o semaphore.o rwsem.o
+obj-y += mutex.o semaphore.o rwsem.o percpu-rwsem.o
 
 ifdef CONFIG_FUNCTION_TRACER
 CFLAGS_REMOVE_lockdep.o = $(CC_FLAGS_FTRACE)
@@ -24,6 +24,5 @@ obj-$(CONFIG_DEBUG_SPINLOCK) += spinlock.o
 obj-$(CONFIG_DEBUG_SPINLOCK) += spinlock_debug.o
 obj-$(CONFIG_RWSEM_GENERIC_SPINLOCK) += rwsem-spinlock.o
 obj-$(CONFIG_RWSEM_XCHGADD_ALGORITHM) += rwsem-xadd.o
-obj-$(CONFIG_PERCPU_RWSEM) += percpu-rwsem.o
 obj-$(CONFIG_QUEUED_RWLOCKS) += qrwlock.o
 obj-$(CONFIG_LOCK_TORTURE_TEST) += locktorture.o

kernel/locking/percpu-rwsem.c

@@ -88,6 +88,19 @@ void percpu_down_read(struct percpu_rw_semaphore *brw)
 	__up_read(&brw->rw_sem);
 }
 
+int percpu_down_read_trylock(struct percpu_rw_semaphore *brw)
+{
+	if (unlikely(!update_fast_ctr(brw, +1))) {
+		if (!__down_read_trylock(&brw->rw_sem))
+			return 0;
+		atomic_inc(&brw->slow_read_ctr);
+		__up_read(&brw->rw_sem);
+	}
+
+	rwsem_acquire_read(&brw->rw_sem.dep_map, 0, 1, _RET_IP_);
+	return 1;
+}
+
 void percpu_up_read(struct percpu_rw_semaphore *brw)
 {
 	rwsem_release(&brw->rw_sem.dep_map, 1, _RET_IP_);

lib/Kconfig

@@ -53,9 +53,6 @@ config GENERIC_IO
 config STMP_DEVICE
 	bool
 
-config PERCPU_RWSEM
-	bool
-
 config ARCH_USE_CMPXCHG_LOCKREF
 	bool
 

mm/backing-dev.c

@@ -55,13 +55,13 @@ static int bdi_debug_stats_show(struct seq_file *m, void *v)
 
 	nr_dirty = nr_io = nr_more_io = nr_dirty_time = 0;
 	spin_lock(&wb->list_lock);
-	list_for_each_entry(inode, &wb->b_dirty, i_wb_list)
+	list_for_each_entry(inode, &wb->b_dirty, i_io_list)
 		nr_dirty++;
-	list_for_each_entry(inode, &wb->b_io, i_wb_list)
+	list_for_each_entry(inode, &wb->b_io, i_io_list)
 		nr_io++;
-	list_for_each_entry(inode, &wb->b_more_io, i_wb_list)
+	list_for_each_entry(inode, &wb->b_more_io, i_io_list)
 		nr_more_io++;
-	list_for_each_entry(inode, &wb->b_dirty_time, i_wb_list)
+	list_for_each_entry(inode, &wb->b_dirty_time, i_io_list)
 		if (inode->i_state & I_DIRTY_TIME)
 			nr_dirty_time++;
 	spin_unlock(&wb->list_lock);

mm/swapfile.c

@@ -2143,11 +2143,10 @@ static int claim_swapfile(struct swap_info_struct *p, struct inode *inode)
 	if (S_ISBLK(inode->i_mode)) {
 		p->bdev = bdgrab(I_BDEV(inode));
 		error = blkdev_get(p->bdev,
-				   FMODE_READ | FMODE_WRITE | FMODE_EXCL,
-				   sys_swapon);
+				   FMODE_READ | FMODE_WRITE | FMODE_EXCL, p);
 		if (error < 0) {
 			p->bdev = NULL;
-			return -EINVAL;
+			return error;
 		}
 		p->old_block_size = block_size(p->bdev);
 		error = set_blocksize(p->bdev, PAGE_SIZE);
@@ -2348,7 +2347,6 @@ SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags)
 	struct filename *name;
 	struct file *swap_file = NULL;
 	struct address_space *mapping;
-	int i;
 	int prio;
 	int error;
 	union swap_header *swap_header;
@@ -2388,19 +2386,8 @@ SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags)
 
 	p->swap_file = swap_file;
 	mapping = swap_file->f_mapping;
-
-	for (i = 0; i < nr_swapfiles; i++) {
-		struct swap_info_struct *q = swap_info[i];
-
-		if (q == p || !q->swap_file)
-			continue;
-		if (mapping == q->swap_file->f_mapping) {
-			error = -EBUSY;
-			goto bad_swap;
-		}
-	}
-
 	inode = mapping->host;
+
 	/* If S_ISREG(inode->i_mode) will do mutex_lock(&inode->i_mutex); */
 	error = claim_swapfile(p, inode);
 	if (unlikely(error))
@@ -2433,6 +2420,8 @@ SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags)
 		goto bad_swap;
 	}
 	if (p->bdev && blk_queue_nonrot(bdev_get_queue(p->bdev))) {
+		int cpu;
+
 		p->flags |= SWP_SOLIDSTATE;
 		/*
 		 * select a random position to start with to help wear leveling
@@ -2451,9 +2440,9 @@ SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags)
 			error = -ENOMEM;
 			goto bad_swap;
 		}
-		for_each_possible_cpu(i) {
+		for_each_possible_cpu(cpu) {
 			struct percpu_cluster *cluster;
-			cluster = per_cpu_ptr(p->percpu_cluster, i);
+			cluster = per_cpu_ptr(p->percpu_cluster, cpu);
 			cluster_set_null(&cluster->index);
 		}
 	}