19 files changed, 227 insertions, 165 deletions

diff --git a/fs/Kconfig b/fs/Kconfig
index cfe512fd1caf..780725a463b1 100644
--- a/fs/Kconfig
+++ b/fs/Kconfig
@@ -68,16 +68,6 @@ source "fs/quota/Kconfig"
 source "fs/autofs4/Kconfig"
 source "fs/fuse/Kconfig"
 
-config CUSE
-        tristate "Character device in Userspace support"
-        depends on FUSE_FS
-        help
-          This FUSE extension allows character devices to be
-          implemented in userspace.
-
-          If you want to develop or use userspace character device
-          based on CUSE, answer Y or M.
-
 config GENERIC_ACL
         bool
         select FS_POSIX_ACL
diff --git a/fs/f2fs/acl.c b/fs/f2fs/acl.c
index e95b94945d5f..137af4255da6 100644
--- a/fs/f2fs/acl.c
+++ b/fs/f2fs/acl.c
@@ -191,15 +191,14 @@ struct posix_acl *f2fs_get_acl(struct inode *inode, int type)
                 retval = f2fs_getxattr(inode, name_index, "", value, retval);
         }
 
-        if (retval < 0) {
-                if (retval == -ENODATA)
-                        acl = NULL;
-                else
-                        acl = ERR_PTR(retval);
-        } else {
+        if (retval > 0)
                 acl = f2fs_acl_from_disk(value, retval);
-        }
+        else if (retval == -ENODATA)
+                acl = NULL;
+        else
+                acl = ERR_PTR(retval);
         kfree(value);
+
         if (!IS_ERR(acl))
                 set_cached_acl(inode, type, acl);
 
diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c
index 6ef36c37e2be..ff3c8439af87 100644
--- a/fs/f2fs/checkpoint.c
+++ b/fs/f2fs/checkpoint.c
@@ -214,7 +214,6 @@ retry:
                 goto retry;
         }
         new->ino = ino;
-        INIT_LIST_HEAD(&new->list);
 
         /* add new_oentry into list which is sorted by inode number */
         if (orphan) {
@@ -772,7 +771,7 @@ void init_orphan_info(struct f2fs_sb_info *sbi)
         sbi->n_orphans = 0;
 }
 
-int create_checkpoint_caches(void)
+int __init create_checkpoint_caches(void)
 {
         orphan_entry_slab = f2fs_kmem_cache_create("f2fs_orphan_entry",
                         sizeof(struct orphan_inode_entry), NULL);
diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index 3aa5ce7cab83..7bd22a201125 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -547,6 +547,15 @@ redirty_out:
 
 #define MAX_DESIRED_PAGES_WP    4096
 
+static int __f2fs_writepage(struct page *page, struct writeback_control *wbc,
+                        void *data)
+{
+        struct address_space *mapping = data;
+        int ret = mapping->a_ops->writepage(page, wbc);
+        mapping_set_error(mapping, ret);
+        return ret;
+}
+
 static int f2fs_write_data_pages(struct address_space *mapping,
                             struct writeback_control *wbc)
 {
@@ -563,7 +572,7 @@ static int f2fs_write_data_pages(struct address_space *mapping,
 
         if (!S_ISDIR(inode->i_mode))
                 mutex_lock(&sbi->writepages);
-        ret = generic_writepages(mapping, wbc);
+        ret = write_cache_pages(mapping, wbc, __f2fs_writepage, mapping);
         if (!S_ISDIR(inode->i_mode))
                 mutex_unlock(&sbi->writepages);
         f2fs_submit_bio(sbi, DATA, (wbc->sync_mode == WB_SYNC_ALL));
@@ -689,6 +698,11 @@ static int f2fs_set_data_page_dirty(struct page *page)
         return 0;
 }
 
+static sector_t f2fs_bmap(struct address_space *mapping, sector_t block)
+{
+        return generic_block_bmap(mapping, block, get_data_block_ro);
+}
+
 const struct address_space_operations f2fs_dblock_aops = {
         .readpage       = f2fs_read_data_page,
         .readpages      = f2fs_read_data_pages,
@@ -700,4 +714,5 @@ const struct address_space_operations f2fs_dblock_aops = {
         .invalidatepage = f2fs_invalidate_data_page,
         .releasepage    = f2fs_release_data_page,
         .direct_IO      = f2fs_direct_IO,
+        .bmap           = f2fs_bmap,
 };
diff --git a/fs/f2fs/debug.c b/fs/f2fs/debug.c
index 0e0380a588ad..c8c37307b326 100644
--- a/fs/f2fs/debug.c
+++ b/fs/f2fs/debug.c
@@ -26,6 +26,7 @@
 
 static LIST_HEAD(f2fs_stat_list);
 static struct dentry *debugfs_root;
+static DEFINE_MUTEX(f2fs_stat_mutex);
 
 static void update_general_status(struct f2fs_sb_info *sbi)
 {
@@ -180,18 +181,14 @@ static int stat_show(struct seq_file *s, void *v)
         int i = 0;
         int j;
 
+        mutex_lock(&f2fs_stat_mutex);
         list_for_each_entry_safe(si, next, &f2fs_stat_list, stat_list) {
 
-                mutex_lock(&si->stat_lock);
-                if (!si->sbi) {
-                        mutex_unlock(&si->stat_lock);
-                        continue;
-                }
                 update_general_status(si->sbi);
 
                 seq_printf(s, "\n=====[ partition info. #%d ]=====\n", i++);
-                seq_printf(s, "[SB: 1] [CP: 2] [NAT: %d] [SIT: %d] ",
-                           si->nat_area_segs, si->sit_area_segs);
+                seq_printf(s, "[SB: 1] [CP: 2] [SIT: %d] [NAT: %d] ",
+                           si->sit_area_segs, si->nat_area_segs);
                 seq_printf(s, "[SSA: %d] [MAIN: %d",
                            si->ssa_area_segs, si->main_area_segs);
                 seq_printf(s, "(OverProv:%d Resv:%d)]\n\n",
@@ -286,8 +283,8 @@ static int stat_show(struct seq_file *s, void *v)
                 seq_printf(s, "\nMemory: %u KB = static: %u + cached: %u\n",
                                 (si->base_mem + si->cache_mem) >> 10,
                                 si->base_mem >> 10, si->cache_mem >> 10);
-                mutex_unlock(&si->stat_lock);
         }
+        mutex_unlock(&f2fs_stat_mutex);
         return 0;
 }
 
@@ -303,7 +300,7 @@ static const struct file_operations stat_fops = {
         .release = single_release,
 };
 
-static int init_stats(struct f2fs_sb_info *sbi)
+int f2fs_build_stats(struct f2fs_sb_info *sbi)
 {
         struct f2fs_super_block *raw_super = F2FS_RAW_SUPER(sbi);
         struct f2fs_stat_info *si;
@@ -313,9 +310,6 @@ static int init_stats(struct f2fs_sb_info *sbi)
                 return -ENOMEM;
 
         si = sbi->stat_info;
-        mutex_init(&si->stat_lock);
-        list_add_tail(&si->stat_list, &f2fs_stat_list);
-
         si->all_area_segs = le32_to_cpu(raw_super->segment_count);
         si->sit_area_segs = le32_to_cpu(raw_super->segment_count_sit);
         si->nat_area_segs = le32_to_cpu(raw_super->segment_count_nat);
@@ -325,21 +319,11 @@ static int init_stats(struct f2fs_sb_info *sbi)
         si->main_area_zones = si->main_area_sections /
                                 le32_to_cpu(raw_super->secs_per_zone);
         si->sbi = sbi;
-        return 0;
-}
 
-int f2fs_build_stats(struct f2fs_sb_info *sbi)
-{
-        int retval;
-
-        retval = init_stats(sbi);
-        if (retval)
-                return retval;
-
-        if (!debugfs_root)
-                debugfs_root = debugfs_create_dir("f2fs", NULL);
+        mutex_lock(&f2fs_stat_mutex);
+        list_add_tail(&si->stat_list, &f2fs_stat_list);
+        mutex_unlock(&f2fs_stat_mutex);
 
-        debugfs_create_file("status", S_IRUGO, debugfs_root, NULL, &stat_fops);
         return 0;
 }
 
@@ -347,14 +331,22 @@ void f2fs_destroy_stats(struct f2fs_sb_info *sbi)
 {
         struct f2fs_stat_info *si = sbi->stat_info;
 
+        mutex_lock(&f2fs_stat_mutex);
         list_del(&si->stat_list);
-        mutex_lock(&si->stat_lock);
-        si->sbi = NULL;
-        mutex_unlock(&si->stat_lock);
+        mutex_unlock(&f2fs_stat_mutex);
+
         kfree(sbi->stat_info);
 }
 
-void destroy_root_stats(void)
+void __init f2fs_create_root_stats(void)
+{
+        debugfs_root = debugfs_create_dir("f2fs", NULL);
+        if (debugfs_root)
+                debugfs_create_file("status", S_IRUGO, debugfs_root,
+                                         NULL, &stat_fops);
+}
+
+void f2fs_destroy_root_stats(void)
 {
         debugfs_remove_recursive(debugfs_root);
         debugfs_root = NULL;
diff --git a/fs/f2fs/dir.c b/fs/f2fs/dir.c
index 951ed52748f6..989980e16d0b 100644
--- a/fs/f2fs/dir.c
+++ b/fs/f2fs/dir.c
@@ -503,7 +503,7 @@ void f2fs_delete_entry(struct f2fs_dir_entry *dentry, struct page *page,
         }
 
         if (inode) {
-                inode->i_ctime = dir->i_ctime = dir->i_mtime = CURRENT_TIME;
+                inode->i_ctime = CURRENT_TIME;
                 drop_nlink(inode);
                 if (S_ISDIR(inode->i_mode)) {
                         drop_nlink(inode);
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 13c6dfbb7183..c8e2d751ef9c 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -211,11 +211,11 @@ struct dnode_of_data {
 static inline void set_new_dnode(struct dnode_of_data *dn, struct inode *inode,
                 struct page *ipage, struct page *npage, nid_t nid)
 {
+        memset(dn, 0, sizeof(*dn));
         dn->inode = inode;
         dn->inode_page = ipage;
         dn->node_page = npage;
         dn->nid = nid;
-        dn->inode_page_locked = 0;
 }
 
 /*
@@ -877,6 +877,8 @@ bool f2fs_empty_dir(struct inode *);
  * super.c
  */
 int f2fs_sync_fs(struct super_block *, int);
+extern __printf(3, 4)
+void f2fs_msg(struct super_block *, const char *, const char *, ...);
 
 /*
  * hash.c
@@ -912,7 +914,7 @@ int restore_node_summary(struct f2fs_sb_info *, unsigned int,
 void flush_nat_entries(struct f2fs_sb_info *);
 int build_node_manager(struct f2fs_sb_info *);
 void destroy_node_manager(struct f2fs_sb_info *);
-int create_node_manager_caches(void);
+int __init create_node_manager_caches(void);
 void destroy_node_manager_caches(void);
 
 /*
@@ -964,7 +966,7 @@ void sync_dirty_dir_inodes(struct f2fs_sb_info *);
 void block_operations(struct f2fs_sb_info *);
 void write_checkpoint(struct f2fs_sb_info *, bool, bool);
 void init_orphan_info(struct f2fs_sb_info *);
-int create_checkpoint_caches(void);
+int __init create_checkpoint_caches(void);
 void destroy_checkpoint_caches(void);
 
 /*
@@ -984,9 +986,9 @@ int do_write_data_page(struct page *);
 int start_gc_thread(struct f2fs_sb_info *);
 void stop_gc_thread(struct f2fs_sb_info *);
 block_t start_bidx_of_node(unsigned int);
-int f2fs_gc(struct f2fs_sb_info *, int);
+int f2fs_gc(struct f2fs_sb_info *);
 void build_gc_manager(struct f2fs_sb_info *);
-int create_gc_caches(void);
+int __init create_gc_caches(void);
 void destroy_gc_caches(void);
 
 /*
@@ -1058,7 +1060,8 @@ struct f2fs_stat_info {
 
 int f2fs_build_stats(struct f2fs_sb_info *);
 void f2fs_destroy_stats(struct f2fs_sb_info *);
-void destroy_root_stats(void);
+void __init f2fs_create_root_stats(void);
+void f2fs_destroy_root_stats(void);
 #else
 #define stat_inc_call_count(si)
 #define stat_inc_seg_count(si, type)
@@ -1068,7 +1071,8 @@ void destroy_root_stats(void);
 
 static inline int f2fs_build_stats(struct f2fs_sb_info *sbi) { return 0; }
 static inline void f2fs_destroy_stats(struct f2fs_sb_info *sbi) { }
-static inline void destroy_root_stats(void) { }
+static inline void __init f2fs_create_root_stats(void) { }
+static inline void f2fs_destroy_root_stats(void) { }
 #endif
 
 extern const struct file_operations f2fs_dir_operations;
diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index 7f9ea9271ebe..3191b52aafb0 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -96,8 +96,9 @@ out:
 }
 
 static const struct vm_operations_struct f2fs_file_vm_ops = {
-        .fault        = filemap_fault,
-        .page_mkwrite = f2fs_vm_page_mkwrite,
+        .fault          = filemap_fault,
+        .page_mkwrite   = f2fs_vm_page_mkwrite,
+        .remap_pages    = generic_file_remap_pages,
 };
 
 static int need_to_sync_dir(struct f2fs_sb_info *sbi, struct inode *inode)
@@ -137,6 +138,9 @@ int f2fs_sync_file(struct file *file, loff_t start, loff_t end, int datasync)
         if (ret)
                 return ret;
 
+        /* guarantee free sections for fsync */
+        f2fs_balance_fs(sbi);
+
         mutex_lock(&inode->i_mutex);
 
         if (datasync && !(inode->i_state & I_DIRTY_DATASYNC))
@@ -407,6 +411,8 @@ int truncate_hole(struct inode *inode, pgoff_t pg_start, pgoff_t pg_end)
                 struct dnode_of_data dn;
                 struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
 
+                f2fs_balance_fs(sbi);
+
                 mutex_lock_op(sbi, DATA_TRUNC);
                 set_new_dnode(&dn, inode, NULL, NULL, 0);
                 err = get_dnode_of_data(&dn, index, RDONLY_NODE);
@@ -534,7 +540,6 @@ static long f2fs_fallocate(struct file *file, int mode,
                                 loff_t offset, loff_t len)
 {
         struct inode *inode = file->f_path.dentry->d_inode;
-        struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
         long ret;
 
         if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE))
@@ -545,7 +550,10 @@ static long f2fs_fallocate(struct file *file, int mode,
         else
                 ret = expand_inode_data(inode, offset, len, mode);
 
-        f2fs_balance_fs(sbi);
+        if (!ret) {
+                inode->i_mtime = inode->i_ctime = CURRENT_TIME;
+                mark_inode_dirty(inode);
+        }
         return ret;
 }
 
diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c
index b0ec721e984a..c386910dacc5 100644
--- a/fs/f2fs/gc.c
+++ b/fs/f2fs/gc.c
@@ -78,7 +78,7 @@ static int gc_thread_func(void *data)
 
                 sbi->bg_gc++;
 
-                if (f2fs_gc(sbi, 1) == GC_NONE)
+                if (f2fs_gc(sbi) == GC_NONE)
                         wait_ms = GC_THREAD_NOGC_SLEEP_TIME;
                 else if (wait_ms == GC_THREAD_NOGC_SLEEP_TIME)
                         wait_ms = GC_THREAD_MAX_SLEEP_TIME;
@@ -424,7 +424,11 @@ next_step:
 }
 
 /*
- * Calculate start block index that this node page contains
+ * Calculate start block index indicating the given node offset.
+ * Be careful, caller should give this node offset only indicating direct node
+ * blocks. If any node offsets, which point the other types of node blocks such
+ * as indirect or double indirect node blocks, are given, it must be a caller's
+ * bug.
  */
 block_t start_bidx_of_node(unsigned int node_ofs)
 {
@@ -651,62 +655,44 @@ static int do_garbage_collect(struct f2fs_sb_info *sbi, unsigned int segno,
         return ret;
 }
 
-int f2fs_gc(struct f2fs_sb_info *sbi, int nGC)
+int f2fs_gc(struct f2fs_sb_info *sbi)
 {
-        unsigned int segno;
-        int old_free_secs, cur_free_secs;
-        int gc_status, nfree;
         struct list_head ilist;
+        unsigned int segno, i;
         int gc_type = BG_GC;
+        int gc_status = GC_NONE;
 
         INIT_LIST_HEAD(&ilist);
 gc_more:
-        nfree = 0;
-        gc_status = GC_NONE;
+        if (!(sbi->sb->s_flags & MS_ACTIVE))
+                goto stop;
 
         if (has_not_enough_free_secs(sbi))
-                old_free_secs = reserved_sections(sbi);
-        else
-                old_free_secs = free_sections(sbi);
-
-        while (sbi->sb->s_flags & MS_ACTIVE) {
-                int i;
-                if (has_not_enough_free_secs(sbi))
-                        gc_type = FG_GC;
+                gc_type = FG_GC;
 
-                cur_free_secs = free_sections(sbi) + nfree;
+        if (!__get_victim(sbi, &segno, gc_type, NO_CHECK_TYPE))
+                goto stop;
 
-                /* We got free space successfully. */
-                if (nGC < cur_free_secs - old_free_secs)
-                        break;
-
-                if (!__get_victim(sbi, &segno, gc_type, NO_CHECK_TYPE))
+        for (i = 0; i < sbi->segs_per_sec; i++) {
+                /*
+                 * do_garbage_collect will give us three gc_status:
+                 * GC_ERROR, GC_DONE, and GC_BLOCKED.
+                 * If GC is finished uncleanly, we have to return
+                 * the victim to dirty segment list.
+                 */
+                gc_status = do_garbage_collect(sbi, segno + i, &ilist, gc_type);
+                if (gc_status != GC_DONE)
                         break;
-
-                for (i = 0; i < sbi->segs_per_sec; i++) {
-                        /*
-                         * do_garbage_collect will give us three gc_status:
-                         * GC_ERROR, GC_DONE, and GC_BLOCKED.
-                         * If GC is finished uncleanly, we have to return
-                         * the victim to dirty segment list.
-                         */
-                        gc_status = do_garbage_collect(sbi, segno + i,
-                                        &ilist, gc_type);
-                        if (gc_status != GC_DONE)
-                                goto stop;
-                        nfree++;
-                }
         }
-stop:
-        if (has_not_enough_free_secs(sbi) || gc_status == GC_BLOCKED) {
+        if (has_not_enough_free_secs(sbi)) {
                 write_checkpoint(sbi, (gc_status == GC_BLOCKED), false);
-                if (nfree)
+                if (has_not_enough_free_secs(sbi))
                         goto gc_more;
         }
+stop:
         mutex_unlock(&sbi->gc_mutex);
 
         put_gc_inode(&ilist);
-        BUG_ON(!list_empty(&ilist));
         return gc_status;
 }
 
@@ -715,7 +701,7 @@ void build_gc_manager(struct f2fs_sb_info *sbi)
         DIRTY_I(sbi)->v_ops = &default_v_ops;
 }
 
-int create_gc_caches(void)
+int __init create_gc_caches(void)
 {
         winode_slab = f2fs_kmem_cache_create("f2fs_gc_inodes",
                         sizeof(struct inode_entry), NULL);
diff --git a/fs/f2fs/inode.c b/fs/f2fs/inode.c
index bf20b4d03214..794241777322 100644
--- a/fs/f2fs/inode.c
+++ b/fs/f2fs/inode.c
@@ -217,6 +217,9 @@ int f2fs_write_inode(struct inode *inode, struct writeback_control *wbc)
                         inode->i_ino == F2FS_META_INO(sbi))
                 return 0;
 
+        if (wbc)
+                f2fs_balance_fs(sbi);
+
         node_page = get_node_page(sbi, inode->i_ino);
         if (IS_ERR(node_page))
                 return PTR_ERR(node_page);
diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
index 5066bfd256c9..9bda63c9c166 100644
--- a/fs/f2fs/node.c
+++ b/fs/f2fs/node.c
@@ -1124,6 +1124,12 @@ static int f2fs_write_node_page(struct page *page,
         return 0;
 }
 
+/*
+ * It is very important to gather dirty pages and write at once, so that we can
+ * submit a big bio without interfering other data writes.
+ * Be default, 512 pages (2MB), a segment size, is quite reasonable.
+ */
+#define COLLECT_DIRTY_NODES     512
 static int f2fs_write_node_pages(struct address_space *mapping,
                             struct writeback_control *wbc)
 {
@@ -1131,17 +1137,16 @@ static int f2fs_write_node_pages(struct address_space *mapping,
         struct block_device *bdev = sbi->sb->s_bdev;
         long nr_to_write = wbc->nr_to_write;
 
-        if (wbc->for_kupdate)
-                return 0;
-
-        if (get_pages(sbi, F2FS_DIRTY_NODES) == 0)
-                return 0;
-
+        /* First check balancing cached NAT entries */
         if (try_to_free_nats(sbi, NAT_ENTRY_PER_BLOCK)) {
                 write_checkpoint(sbi, false, false);
                 return 0;
         }
 
+        /* collect a number of dirty node pages and write together */
+        if (get_pages(sbi, F2FS_DIRTY_NODES) < COLLECT_DIRTY_NODES)
+                return 0;
+
         /* if mounting is failed, skip writing node pages */
         wbc->nr_to_write = bio_get_nr_vecs(bdev);
         sync_node_pages(sbi, 0, wbc);
@@ -1732,7 +1737,7 @@ void destroy_node_manager(struct f2fs_sb_info *sbi)
         kfree(nm_i);
 }
 
-int create_node_manager_caches(void)
+int __init create_node_manager_caches(void)
 {
         nat_entry_slab = f2fs_kmem_cache_create("nat_entry",
                         sizeof(struct nat_entry), NULL);
diff --git a/fs/f2fs/recovery.c b/fs/f2fs/recovery.c
index b571fee677d5..f42e4060b399 100644
--- a/fs/f2fs/recovery.c
+++ b/fs/f2fs/recovery.c
@@ -67,7 +67,7 @@ static int recover_dentry(struct page *ipage, struct inode *inode)
                 kunmap(page);
                 f2fs_put_page(page, 0);
         } else {
-                f2fs_add_link(&dent, inode);
+                err = f2fs_add_link(&dent, inode);
         }
         iput(dir);
 out:
@@ -151,7 +151,6 @@ static int find_fsync_dnodes(struct f2fs_sb_info *sbi, struct list_head *head)
                                 goto out;
                         }
 
-                        INIT_LIST_HEAD(&entry->list);
                         list_add_tail(&entry->list, head);
                         entry->blkaddr = blkaddr;
                 }
@@ -174,10 +173,9 @@ out:
 static void destroy_fsync_dnodes(struct f2fs_sb_info *sbi,
                                         struct list_head *head)
 {
-        struct list_head *this;
-        struct fsync_inode_entry *entry;
-        list_for_each(this, head) {
-                entry = list_entry(this, struct fsync_inode_entry, list);
+        struct fsync_inode_entry *entry, *tmp;
+
+        list_for_each_entry_safe(entry, tmp, head, list) {
                 iput(entry->inode);
                 list_del(&entry->list);
                 kmem_cache_free(fsync_entry_slab, entry);
diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
index de6240922b0a..4b0099066582 100644
--- a/fs/f2fs/segment.c
+++ b/fs/f2fs/segment.c
@@ -31,7 +31,7 @@ void f2fs_balance_fs(struct f2fs_sb_info *sbi)
          */
         if (has_not_enough_free_secs(sbi)) {
                 mutex_lock(&sbi->gc_mutex);
-                f2fs_gc(sbi, 1);
+                f2fs_gc(sbi);
         }
 }
 
diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
index 08a94c814bdc..37fad04c8669 100644
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -53,6 +53,18 @@ static match_table_t f2fs_tokens = {
         {Opt_err, NULL},
 };
 
+void f2fs_msg(struct super_block *sb, const char *level, const char *fmt, ...)
+{
+        struct va_format vaf;
+        va_list args;
+
+        va_start(args, fmt);
+        vaf.fmt = fmt;
+        vaf.va = &args;
+        printk("%sF2FS-fs (%s): %pV\n", level, sb->s_id, &vaf);
+        va_end(args);
+}
+
 static void init_once(void *foo)
 {
         struct f2fs_inode_info *fi = (struct f2fs_inode_info *) foo;
@@ -125,6 +137,8 @@ int f2fs_sync_fs(struct super_block *sb, int sync)
 
         if (sync)
                 write_checkpoint(sbi, false, false);
+        else
+                f2fs_balance_fs(sbi);
 
         return 0;
 }
@@ -247,7 +261,8 @@ static const struct export_operations f2fs_export_ops = {
         .get_parent = f2fs_get_parent,
 };
 
-static int parse_options(struct f2fs_sb_info *sbi, char *options)
+static int parse_options(struct super_block *sb, struct f2fs_sb_info *sbi,
+                                char *options)
 {
         substring_t args[MAX_OPT_ARGS];
         char *p;
@@ -286,7 +301,8 @@ static int parse_options(struct f2fs_sb_info *sbi, char *options)
                         break;
 #else
                 case Opt_nouser_xattr:
-                        pr_info("nouser_xattr options not supported\n");
+                        f2fs_msg(sb, KERN_INFO,
+                                "nouser_xattr options not supported");
                         break;
 #endif
 #ifdef CONFIG_F2FS_FS_POSIX_ACL
@@ -295,7 +311,7 @@ static int parse_options(struct f2fs_sb_info *sbi, char *options)
                         break;
 #else
                 case Opt_noacl:
-                        pr_info("noacl options not supported\n");
+                        f2fs_msg(sb, KERN_INFO, "noacl options not supported");
                         break;
 #endif
                 case Opt_active_logs:
@@ -309,8 +325,9 @@ static int parse_options(struct f2fs_sb_info *sbi, char *options)
                         set_opt(sbi, DISABLE_EXT_IDENTIFY);
                         break;
                 default:
-                        pr_err("Unrecognized mount option \"%s\" or missing value\n",
-                                        p);
+                        f2fs_msg(sb, KERN_ERR,
+                                "Unrecognized mount option \"%s\" or missing value",
+                                p);
                         return -EINVAL;
                 }
         }
@@ -337,23 +354,36 @@ static loff_t max_file_size(unsigned bits)
         return result;
 }
 
-static int sanity_check_raw_super(struct f2fs_super_block *raw_super)
+static int sanity_check_raw_super(struct super_block *sb,
+                        struct f2fs_super_block *raw_super)
 {
         unsigned int blocksize;
 
-        if (F2FS_SUPER_MAGIC != le32_to_cpu(raw_super->magic))
+        if (F2FS_SUPER_MAGIC != le32_to_cpu(raw_super->magic)) {
+                f2fs_msg(sb, KERN_INFO,
+                        "Magic Mismatch, valid(0x%x) - read(0x%x)",
+                        F2FS_SUPER_MAGIC, le32_to_cpu(raw_super->magic));
                 return 1;
+        }
 
         /* Currently, support only 4KB block size */
         blocksize = 1 << le32_to_cpu(raw_super->log_blocksize);
-        if (blocksize != PAGE_CACHE_SIZE)
+        if (blocksize != PAGE_CACHE_SIZE) {
+                f2fs_msg(sb, KERN_INFO,
+                        "Invalid blocksize (%u), supports only 4KB\n",
+                        blocksize);
                 return 1;
+        }
         if (le32_to_cpu(raw_super->log_sectorsize) !=
-                                        F2FS_LOG_SECTOR_SIZE)
+                                        F2FS_LOG_SECTOR_SIZE) {
+                f2fs_msg(sb, KERN_INFO, "Invalid log sectorsize");
                 return 1;
+        }
         if (le32_to_cpu(raw_super->log_sectors_per_block) !=
-                                        F2FS_LOG_SECTORS_PER_BLOCK)
+                                        F2FS_LOG_SECTORS_PER_BLOCK) {
+                f2fs_msg(sb, KERN_INFO, "Invalid log sectors per block");
                 return 1;
+        }
         return 0;
 }
 
@@ -413,14 +443,17 @@ static int f2fs_fill_super(struct super_block *sb, void *data, int silent)
         if (!sbi)
                 return -ENOMEM;
 
-        /* set a temporary block size */
-        if (!sb_set_blocksize(sb, F2FS_BLKSIZE))
+        /* set a block size */
+        if (!sb_set_blocksize(sb, F2FS_BLKSIZE)) {
+                f2fs_msg(sb, KERN_ERR, "unable to set blocksize");
                 goto free_sbi;
+        }
 
         /* read f2fs raw super block */
         raw_super_buf = sb_bread(sb, 0);
         if (!raw_super_buf) {
                 err = -EIO;
+                f2fs_msg(sb, KERN_ERR, "unable to read superblock");
                 goto free_sbi;
         }
         raw_super = (struct f2fs_super_block *)
@@ -438,12 +471,14 @@ static int f2fs_fill_super(struct super_block *sb, void *data, int silent)
         set_opt(sbi, POSIX_ACL);
 #endif
         /* parse mount options */
-        if (parse_options(sbi, (char *)data))
+        if (parse_options(sb, sbi, (char *)data))
                 goto free_sb_buf;
 
         /* sanity checking of raw super */
-        if (sanity_check_raw_super(raw_super))
+        if (sanity_check_raw_super(sb, raw_super)) {
+                f2fs_msg(sb, KERN_ERR, "Can't find a valid F2FS filesystem");
                 goto free_sb_buf;
+        }
 
         sb->s_maxbytes = max_file_size(le32_to_cpu(raw_super->log_blocksize));
         sb->s_max_links = F2FS_LINK_MAX;
@@ -477,18 +512,23 @@ static int f2fs_fill_super(struct super_block *sb, void *data, int silent)
         /* get an inode for meta space */
         sbi->meta_inode = f2fs_iget(sb, F2FS_META_INO(sbi));
         if (IS_ERR(sbi->meta_inode)) {
+                f2fs_msg(sb, KERN_ERR, "Failed to read F2FS meta data inode");
                 err = PTR_ERR(sbi->meta_inode);
                 goto free_sb_buf;
         }
 
         err = get_valid_checkpoint(sbi);
-        if (err)
+        if (err) {
+                f2fs_msg(sb, KERN_ERR, "Failed to get valid F2FS checkpoint");
                 goto free_meta_inode;
+        }
 
         /* sanity checking of checkpoint */
         err = -EINVAL;
-        if (sanity_check_ckpt(raw_super, sbi->ckpt))
+        if (sanity_check_ckpt(raw_super, sbi->ckpt)) {
+                f2fs_msg(sb, KERN_ERR, "Invalid F2FS checkpoint");
                 goto free_cp;
+        }
 
         sbi->total_valid_node_count =
                                 le32_to_cpu(sbi->ckpt->valid_node_count);
@@ -502,25 +542,28 @@ static int f2fs_fill_super(struct super_block *sb, void *data, int silent)
         INIT_LIST_HEAD(&sbi->dir_inode_list);
         spin_lock_init(&sbi->dir_inode_lock);
 
-        /* init super block */
-        if (!sb_set_blocksize(sb, sbi->blocksize))
-                goto free_cp;
-
         init_orphan_info(sbi);
 
         /* setup f2fs internal modules */
         err = build_segment_manager(sbi);
-        if (err)
+        if (err) {
+                f2fs_msg(sb, KERN_ERR,
+                        "Failed to initialize F2FS segment manager");
                 goto free_sm;
+        }
         err = build_node_manager(sbi);
-        if (err)
+        if (err) {
+                f2fs_msg(sb, KERN_ERR,
+                        "Failed to initialize F2FS node manager");
                 goto free_nm;
+        }
 
         build_gc_manager(sbi);
 
         /* get an inode for node space */
         sbi->node_inode = f2fs_iget(sb, F2FS_NODE_INO(sbi));
         if (IS_ERR(sbi->node_inode)) {
+                f2fs_msg(sb, KERN_ERR, "Failed to read node inode");
                 err = PTR_ERR(sbi->node_inode);
                 goto free_nm;
         }
@@ -533,6 +576,7 @@ static int f2fs_fill_super(struct super_block *sb, void *data, int silent)
         /* read root inode and dentry */
         root = f2fs_iget(sb, F2FS_ROOT_INO(sbi));
         if (IS_ERR(root)) {
+                f2fs_msg(sb, KERN_ERR, "Failed to read root inode");
                 err = PTR_ERR(root);
                 goto free_node_inode;
         }
@@ -596,7 +640,7 @@ static struct file_system_type f2fs_fs_type = {
         .fs_flags       = FS_REQUIRES_DEV,
 };
 
-static int init_inodecache(void)
+static int __init init_inodecache(void)
 {
         f2fs_inode_cachep = f2fs_kmem_cache_create("f2fs_inode_cache",
                         sizeof(struct f2fs_inode_info), NULL);
@@ -631,14 +675,17 @@ static int __init init_f2fs_fs(void)
         err = create_checkpoint_caches();
         if (err)
                 goto fail;
-        return register_filesystem(&f2fs_fs_type);
+        err = register_filesystem(&f2fs_fs_type);
+        if (err)
+                goto fail;
+        f2fs_create_root_stats();
 fail:
         return err;
 }
 
 static void __exit exit_f2fs_fs(void)
 {
-        destroy_root_stats();
+        f2fs_destroy_root_stats();
         unregister_filesystem(&f2fs_fs_type);
         destroy_checkpoint_caches();
         destroy_gc_caches();
diff --git a/fs/f2fs/xattr.c b/fs/f2fs/xattr.c
index 940136a3d3a6..8038c0496504 100644
--- a/fs/f2fs/xattr.c
+++ b/fs/f2fs/xattr.c
@@ -318,6 +318,8 @@ int f2fs_setxattr(struct inode *inode, int name_index, const char *name,
         if (name_len > 255 || value_len > MAX_VALUE_LEN)
                 return -ERANGE;
 
+        f2fs_balance_fs(sbi);
+
         mutex_lock_op(sbi, NODE_NEW);
         if (!fi->i_xattr_nid) {
                 /* Allocate new attribute block */
diff --git a/fs/fuse/Kconfig b/fs/fuse/Kconfig
index 0cf160a94eda..1b2f6c2c3aaf 100644
--- a/fs/fuse/Kconfig
+++ b/fs/fuse/Kconfig
@@ -4,12 +4,24 @@ config FUSE_FS
           With FUSE it is possible to implement a fully functional filesystem
           in a userspace program.
 
-          There's also companion library: libfuse.  This library along with
-          utilities is available from the FUSE homepage:
+          There's also a companion library: libfuse2.  This library is available
+          from the FUSE homepage:
           <http://fuse.sourceforge.net/>
+          although chances are your distribution already has that library
+          installed if you've installed the "fuse" package itself.
 
           See <file:Documentation/filesystems/fuse.txt> for more information.
           See <file:Documentation/Changes> for needed library/utility version.
 
           If you want to develop a userspace FS, or if you want to use
           a filesystem based on FUSE, answer Y or M.
+
+config CUSE
+        tristate "Character device in Userspace support"
+        depends on FUSE_FS
+        help
+          This FUSE extension allows character devices to be
+          implemented in userspace.
+
+          If you want to develop or use a userspace character device
+          based on CUSE, answer Y or M.
diff --git a/fs/fuse/cuse.c b/fs/fuse/cuse.c
index ee8d55042298..e397b675b029 100644
--- a/fs/fuse/cuse.c
+++ b/fs/fuse/cuse.c
@@ -45,7 +45,6 @@
 #include <linux/miscdevice.h>
 #include <linux/mutex.h>
 #include <linux/slab.h>
-#include <linux/spinlock.h>
 #include <linux/stat.h>
 #include <linux/module.h>
 
@@ -63,7 +62,7 @@ struct cuse_conn {
         bool                    unrestricted_ioctl;
 };
 
-static DEFINE_SPINLOCK(cuse_lock);              /* protects cuse_conntbl */
+static DEFINE_MUTEX(cuse_lock);         /* protects registration */
 static struct list_head cuse_conntbl[CUSE_CONNTBL_LEN];
 static struct class *cuse_class;
 
@@ -114,14 +113,14 @@ static int cuse_open(struct inode *inode, struct file *file)
         int rc;
 
         /* look up and get the connection */
-        spin_lock(&cuse_lock);
+        mutex_lock(&cuse_lock);
         list_for_each_entry(pos, cuse_conntbl_head(devt), list)
                 if (pos->dev->devt == devt) {
                         fuse_conn_get(&pos->fc);
                         cc = pos;
                         break;
                 }
-        spin_unlock(&cuse_lock);
+        mutex_unlock(&cuse_lock);
 
         /* dead? */
         if (!cc)
@@ -267,7 +266,7 @@ static int cuse_parse_one(char **pp, char *end, char **keyp, char **valp)
 static int cuse_parse_devinfo(char *p, size_t len, struct cuse_devinfo *devinfo)
 {
         char *end = p + len;
-        char *key, *val;
+        char *uninitialized_var(key), *uninitialized_var(val);
         int rc;
 
         while (true) {
@@ -305,14 +304,14 @@ static void cuse_gendev_release(struct device *dev)
  */
 static void cuse_process_init_reply(struct fuse_conn *fc, struct fuse_req *req)
 {
-        struct cuse_conn *cc = fc_to_cc(fc);
+        struct cuse_conn *cc = fc_to_cc(fc), *pos;
         struct cuse_init_out *arg = req->out.args[0].value;
         struct page *page = req->pages[0];
         struct cuse_devinfo devinfo = { };
         struct device *dev;
         struct cdev *cdev;
         dev_t devt;
-        int rc;
+        int rc, i;
 
         if (req->out.h.error ||
             arg->major != FUSE_KERNEL_VERSION || arg->minor < 11) {
@@ -356,15 +355,24 @@ static void cuse_process_init_reply(struct fuse_conn *fc, struct fuse_req *req)
         dev_set_drvdata(dev, cc);
         dev_set_name(dev, "%s", devinfo.name);
 
+        mutex_lock(&cuse_lock);
+
+        /* make sure the device-name is unique */
+        for (i = 0; i < CUSE_CONNTBL_LEN; ++i) {
+                list_for_each_entry(pos, &cuse_conntbl[i], list)
+                        if (!strcmp(dev_name(pos->dev), dev_name(dev)))
+                                goto err_unlock;
+        }
+
         rc = device_add(dev);
         if (rc)
-                goto err_device;
+                goto err_unlock;
 
         /* register cdev */
         rc = -ENOMEM;
         cdev = cdev_alloc();
         if (!cdev)
-                goto err_device;
+                goto err_unlock;
 
         cdev->owner = THIS_MODULE;
         cdev->ops = &cuse_frontend_fops;
@@ -377,9 +385,8 @@ static void cuse_process_init_reply(struct fuse_conn *fc, struct fuse_req *req)
         cc->cdev = cdev;
 
         /* make the device available */
-        spin_lock(&cuse_lock);
         list_add(&cc->list, cuse_conntbl_head(devt));
-        spin_unlock(&cuse_lock);
+        mutex_unlock(&cuse_lock);
 
         /* announce device availability */
         dev_set_uevent_suppress(dev, 0);
@@ -391,7 +398,8 @@ out:
 
 err_cdev:
         cdev_del(cdev);
-err_device:
+err_unlock:
+        mutex_unlock(&cuse_lock);
         put_device(dev);
 err_region:
         unregister_chrdev_region(devt, 1);
@@ -520,9 +528,9 @@ static int cuse_channel_release(struct inode *inode, struct file *file)
         int rc;
 
         /* remove from the conntbl, no more access from this point on */
-        spin_lock(&cuse_lock);
+        mutex_lock(&cuse_lock);
         list_del_init(&cc->list);
-        spin_unlock(&cuse_lock);
+        mutex_unlock(&cuse_lock);
 
         /* remove device */
         if (cc->dev)
diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c
index c16335315e5d..e83351aa5bad 100644
--- a/fs/fuse/dev.c
+++ b/fs/fuse/dev.c
@@ -692,8 +692,6 @@ static int fuse_try_move_page(struct fuse_copy_state *cs, struct page **pagep)
         struct page *oldpage = *pagep;
         struct page *newpage;
         struct pipe_buffer *buf = cs->pipebufs;
-        struct address_space *mapping;
-        pgoff_t index;
 
         unlock_request(cs->fc, cs->req);
         fuse_copy_finish(cs);
@@ -724,9 +722,6 @@ static int fuse_try_move_page(struct fuse_copy_state *cs, struct page **pagep)
         if (fuse_check_page(newpage) != 0)
                 goto out_fallback_unlock;
 
-        mapping = oldpage->mapping;
-        index = oldpage->index;
-
         /*
          * This is a new and locked page, it shouldn't be mapped or
          * have any special flags on it
diff --git a/fs/fuse/file.c b/fs/fuse/file.c
index e21d4d8f87e3..f3ab824fa302 100644
--- a/fs/fuse/file.c
+++ b/fs/fuse/file.c
@@ -2177,8 +2177,8 @@ fuse_direct_IO(int rw, struct kiocb *iocb, const struct iovec *iov,
         return ret;
 }
 
-long fuse_file_fallocate(struct file *file, int mode, loff_t offset,
-                            loff_t length)
+static long fuse_file_fallocate(struct file *file, int mode, loff_t offset,
+                                loff_t length)
 {
         struct fuse_file *ff = file->private_data;
         struct fuse_conn *fc = ff->fc;
@@ -2213,7 +2213,6 @@ long fuse_file_fallocate(struct file *file, int mode, loff_t offset,
 
         return err;
 }
-EXPORT_SYMBOL_GPL(fuse_file_fallocate);
 
 static const struct file_operations fuse_file_operations = {
         .llseek         = fuse_file_llseek,