5 files changed, 58 insertions, 41 deletions

diff --git a/fs/block_dev.c b/fs/block_dev.c
index 4e847e53051f..dea3b628a6ce 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -59,7 +59,7 @@ static void bdev_inode_switch_bdi(struct inode *inode,
         spin_lock(&inode_lock);
         inode->i_data.backing_dev_info = dst;
         if (inode->i_state & I_DIRTY)
-                list_move(&inode->i_list, &dst->wb.b_dirty);
+                list_move(&inode->i_wb_list, &dst->wb.b_dirty);
         spin_unlock(&inode_lock);
 }
 
diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index e8f65290e836..7a24cc957f05 100644
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -79,6 +79,11 @@ static inline struct backing_dev_info *inode_to_bdi(struct inode *inode)
         return sb->s_bdi;
 }
 
+static inline struct inode *wb_inode(struct list_head *head)
+{
+        return list_entry(head, struct inode, i_wb_list);
+}
+
 static void bdi_queue_work(struct backing_dev_info *bdi,
                 struct wb_writeback_work *work)
 {
@@ -172,11 +177,11 @@ static void redirty_tail(struct inode *inode)
         if (!list_empty(&wb->b_dirty)) {
                 struct inode *tail;
 
-                tail = list_entry(wb->b_dirty.next, struct inode, i_list);
+                tail = wb_inode(wb->b_dirty.next);
                 if (time_before(inode->dirtied_when, tail->dirtied_when))
                         inode->dirtied_when = jiffies;
         }
-        list_move(&inode->i_list, &wb->b_dirty);
+        list_move(&inode->i_wb_list, &wb->b_dirty);
 }
 
 /*
@@ -186,7 +191,7 @@ static void requeue_io(struct inode *inode)
 {
         struct bdi_writeback *wb = &inode_to_bdi(inode)->wb;
 
-        list_move(&inode->i_list, &wb->b_more_io);
+        list_move(&inode->i_wb_list, &wb->b_more_io);
 }
 
 static void inode_sync_complete(struct inode *inode)
@@ -227,14 +232,14 @@ static void move_expired_inodes(struct list_head *delaying_queue,
         int do_sb_sort = 0;
 
         while (!list_empty(delaying_queue)) {
-                inode = list_entry(delaying_queue->prev, struct inode, i_list);
+                inode = wb_inode(delaying_queue->prev);
                 if (older_than_this &&
                     inode_dirtied_after(inode, *older_than_this))
                         break;
                 if (sb && sb != inode->i_sb)
                         do_sb_sort = 1;
                 sb = inode->i_sb;
-                list_move(&inode->i_list, &tmp);
+                list_move(&inode->i_wb_list, &tmp);
         }
 
         /* just one sb in list, splice to dispatch_queue and we're done */
@@ -245,12 +250,11 @@ static void move_expired_inodes(struct list_head *delaying_queue,
 
         /* Move inodes from one superblock together */
         while (!list_empty(&tmp)) {
-                inode = list_entry(tmp.prev, struct inode, i_list);
-                sb = inode->i_sb;
+                sb = wb_inode(tmp.prev)->i_sb;
                 list_for_each_prev_safe(pos, node, &tmp) {
-                        inode = list_entry(pos, struct inode, i_list);
+                        inode = wb_inode(pos);
                         if (inode->i_sb == sb)
-                                list_move(&inode->i_list, dispatch_queue);
+                                list_move(&inode->i_wb_list, dispatch_queue);
                 }
         }
 }
@@ -414,7 +418,7 @@ writeback_single_inode(struct inode *inode, struct writeback_control *wbc)
                          * a reference to the inode or it's on it's way out.
                          * No need to add it back to the LRU.
                          */
-                        list_del_init(&inode->i_list);
+                        list_del_init(&inode->i_wb_list);
                 }
         }
         inode_sync_complete(inode);
@@ -462,8 +466,7 @@ static int writeback_sb_inodes(struct super_block *sb, struct bdi_writeback *wb,
 {
         while (!list_empty(&wb->b_io)) {
                 long pages_skipped;
-                struct inode *inode = list_entry(wb->b_io.prev,
-                                                 struct inode, i_list);
+                struct inode *inode = wb_inode(wb->b_io.prev);
 
                 if (inode->i_sb != sb) {
                         if (only_this_sb) {
@@ -533,8 +536,7 @@ void writeback_inodes_wb(struct bdi_writeback *wb,
                 queue_io(wb, wbc->older_than_this);
 
         while (!list_empty(&wb->b_io)) {
-                struct inode *inode = list_entry(wb->b_io.prev,
-                                                 struct inode, i_list);
+                struct inode *inode = wb_inode(wb->b_io.prev);
                 struct super_block *sb = inode->i_sb;
 
                 if (!pin_sb_for_writeback(sb)) {
@@ -672,8 +674,7 @@ static long wb_writeback(struct bdi_writeback *wb,
                  */
                 spin_lock(&inode_lock);
                 if (!list_empty(&wb->b_more_io))  {
-                        inode = list_entry(wb->b_more_io.prev,
-                                                struct inode, i_list);
+                        inode = wb_inode(wb->b_more_io.prev);
                         trace_wbc_writeback_wait(&wbc, wb->bdi);
                         inode_wait_for_writeback(inode);
                 }
@@ -987,7 +988,7 @@ void __mark_inode_dirty(struct inode *inode, int flags)
                         }
 
                         inode->dirtied_when = jiffies;
-                        list_move(&inode->i_list, &bdi->wb.b_dirty);
+                        list_move(&inode->i_wb_list, &bdi->wb.b_dirty);
                 }
         }
 out:
diff --git a/fs/inode.c b/fs/inode.c
index 4bedac32154f..09e2d7a5f1d2 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -71,7 +71,7 @@ static unsigned int i_hash_shift __read_mostly;
  * allowing for low-overhead inode sync() operations.
  */
 
-static LIST_HEAD(inode_unused);
+static LIST_HEAD(inode_lru);
 static struct hlist_head *inode_hashtable __read_mostly;
 
 /*
@@ -271,6 +271,7 @@ EXPORT_SYMBOL(__destroy_inode);
 
 static void destroy_inode(struct inode *inode)
 {
+        BUG_ON(!list_empty(&inode->i_lru));
         __destroy_inode(inode);
         if (inode->i_sb->s_op->destroy_inode)
                 inode->i_sb->s_op->destroy_inode(inode);
@@ -289,7 +290,8 @@ void inode_init_once(struct inode *inode)
         INIT_HLIST_NODE(&inode->i_hash);
         INIT_LIST_HEAD(&inode->i_dentry);
         INIT_LIST_HEAD(&inode->i_devices);
-        INIT_LIST_HEAD(&inode->i_list);
+        INIT_LIST_HEAD(&inode->i_wb_list);
+        INIT_LIST_HEAD(&inode->i_lru);
         INIT_RADIX_TREE(&inode->i_data.page_tree, GFP_ATOMIC);
         spin_lock_init(&inode->i_data.tree_lock);
         spin_lock_init(&inode->i_data.i_mmap_lock);
@@ -330,16 +332,16 @@ EXPORT_SYMBOL(ihold);
 
 static void inode_lru_list_add(struct inode *inode)
 {
-        if (list_empty(&inode->i_list)) {
-                list_add(&inode->i_list, &inode_unused);
+        if (list_empty(&inode->i_lru)) {
+                list_add(&inode->i_lru, &inode_lru);
                 percpu_counter_inc(&nr_inodes_unused);
         }
 }
 
 static void inode_lru_list_del(struct inode *inode)
 {
-        if (!list_empty(&inode->i_list)) {
-                list_del_init(&inode->i_list);
+        if (!list_empty(&inode->i_lru)) {
+                list_del_init(&inode->i_lru);
                 percpu_counter_dec(&nr_inodes_unused);
         }
 }
@@ -460,8 +462,8 @@ static void dispose_list(struct list_head *head)
         while (!list_empty(head)) {
                 struct inode *inode;
 
-                inode = list_first_entry(head, struct inode, i_list);
-                list_del_init(&inode->i_list);
+                inode = list_first_entry(head, struct inode, i_lru);
+                list_del_init(&inode->i_lru);
 
                 evict(inode);
 
@@ -507,8 +509,14 @@ static int invalidate_list(struct list_head *head, struct list_head *dispose)
                         continue;
                 }
 
-                list_move(&inode->i_list, dispose);
                 inode->i_state |= I_FREEING;
+
+                /*
+                 * Move the inode off the IO lists and LRU once I_FREEING is
+                 * set so that it won't get moved back on there if it is dirty.
+                 */
+                list_move(&inode->i_lru, dispose);
+                list_del_init(&inode->i_wb_list);
                 if (!(inode->i_state & (I_DIRTY | I_SYNC)))
                         percpu_counter_dec(&nr_inodes_unused);
         }
@@ -580,10 +588,10 @@ static void prune_icache(int nr_to_scan)
         for (nr_scanned = 0; nr_scanned < nr_to_scan; nr_scanned++) {
                 struct inode *inode;
 
-                if (list_empty(&inode_unused))
+                if (list_empty(&inode_lru))
                         break;
 
-                inode = list_entry(inode_unused.prev, struct inode, i_list);
+                inode = list_entry(inode_lru.prev, struct inode, i_lru);
 
                 /*
                  * Referenced or dirty inodes are still in use. Give them
@@ -591,14 +599,14 @@ static void prune_icache(int nr_to_scan)
                  */
                 if (atomic_read(&inode->i_count) ||
                     (inode->i_state & ~I_REFERENCED)) {
-                        list_del_init(&inode->i_list);
+                        list_del_init(&inode->i_lru);
                         percpu_counter_dec(&nr_inodes_unused);
                         continue;
                 }
 
                 /* recently referenced inodes get one more pass */
                 if (inode->i_state & I_REFERENCED) {
-                        list_move(&inode->i_list, &inode_unused);
+                        list_move(&inode->i_lru, &inode_lru);
                         inode->i_state &= ~I_REFERENCED;
                         continue;
                 }
@@ -611,15 +619,21 @@ static void prune_icache(int nr_to_scan)
                         iput(inode);
                         spin_lock(&inode_lock);
 
-                        if (inode != list_entry(inode_unused.next,
-                                                struct inode, i_list))
+                        if (inode != list_entry(inode_lru.next,
+                                                struct inode, i_lru))
                                 continue;       /* wrong inode or list_empty */
                         if (!can_unuse(inode))
                                 continue;
                 }
-                list_move(&inode->i_list, &freeable);
                 WARN_ON(inode->i_state & I_NEW);
                 inode->i_state |= I_FREEING;
+
+                /*
+                 * Move the inode off the IO lists and LRU once I_FREEING is
+                 * set so that it won't get moved back on there if it is dirty.
+                 */
+                list_move(&inode->i_lru, &freeable);
+                list_del_init(&inode->i_wb_list);
                 percpu_counter_dec(&nr_inodes_unused);
         }
         if (current_is_kswapd())
@@ -1340,15 +1354,16 @@ static void iput_final(struct inode *inode)
                 inode->i_state &= ~I_WILL_FREE;
                 __remove_inode_hash(inode);
         }
+
         WARN_ON(inode->i_state & I_NEW);
         inode->i_state |= I_FREEING;
 
         /*
-         * After we delete the inode from the LRU here, we avoid moving dirty
-         * inodes back onto the LRU now because I_FREEING is set and hence
-         * writeback_single_inode() won't move the inode around.
+         * Move the inode off the IO lists and LRU once I_FREEING is
+         * set so that it won't get moved back on there if it is dirty.
          */
         inode_lru_list_del(inode);
+        list_del_init(&inode->i_wb_list);
 
         __inode_sb_list_del(inode);
         spin_unlock(&inode_lock);
diff --git a/include/linux/fs.h b/include/linux/fs.h
index d58059944801..f300a6508818 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -723,7 +723,8 @@ struct posix_acl;
 
 struct inode {
         struct hlist_node       i_hash;
-        struct list_head        i_list;         /* backing dev IO list */
+        struct list_head        i_wb_list;      /* backing dev IO list */
+        struct list_head        i_lru;          /* inode LRU list */
         struct list_head        i_sb_list;
         struct list_head        i_dentry;
         unsigned long           i_ino;
diff --git a/mm/backing-dev.c b/mm/backing-dev.c
index 65d420499a61..15d5097de821 100644
--- a/mm/backing-dev.c
+++ b/mm/backing-dev.c
@@ -74,11 +74,11 @@ static int bdi_debug_stats_show(struct seq_file *m, void *v)
 
         nr_wb = nr_dirty = nr_io = nr_more_io = 0;
         spin_lock(&inode_lock);
-        list_for_each_entry(inode, &wb->b_dirty, i_list)
+        list_for_each_entry(inode, &wb->b_dirty, i_wb_list)
                 nr_dirty++;
-        list_for_each_entry(inode, &wb->b_io, i_list)
+        list_for_each_entry(inode, &wb->b_io, i_wb_list)
                 nr_io++;
-        list_for_each_entry(inode, &wb->b_more_io, i_list)
+        list_for_each_entry(inode, &wb->b_more_io, i_wb_list)
                 nr_more_io++;
         spin_unlock(&inode_lock);