Btrfs: early fsync support

Signed-off-by: Chris Mason <chris.mason@oracle.com>

1 files changed, 36 insertions, 1 deletions

diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index dff2db0d1dc2..f99c764a59db 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -11,6 +11,7 @@
 #include <linux/mpage.h>
 #include <linux/swap.h>
 #include <linux/writeback.h>
+#include <linux/statfs.h>
 #include "ctree.h"
 #include "disk-io.h"
 #include "transaction.h"
@@ -932,6 +933,26 @@ out_unlock:
         return err;
 }
 
+static int btrfs_sync_file(struct file *file,
+                           struct dentry *dentry, int datasync)
+{
+        struct inode *inode = dentry->d_inode;
+        struct btrfs_root *root = BTRFS_I(inode)->root;
+        int ret;
+        struct btrfs_trans_handle *trans;
+
+        mutex_lock(&root->fs_info->fs_mutex);
+        trans = btrfs_start_transaction(root, 1);
+        if (!trans) {
+                ret = -ENOMEM;
+                goto out;
+        }
+        ret = btrfs_commit_transaction(trans, root);
+        mutex_unlock(&root->fs_info->fs_mutex);
+out:
+        return ret > 0 ? EIO : ret;
+}
+
 static int btrfs_sync_fs(struct super_block *sb, int wait)
 {
         struct btrfs_trans_handle *trans;
@@ -2353,6 +2374,19 @@ static int btrfs_getattr(struct vfsmount *mnt,
         return 0;
 }
 
+static int btrfs_statfs(struct dentry *dentry, struct kstatfs *buf)
+{
+        struct btrfs_root *root = btrfs_sb(dentry->d_sb);
+        struct btrfs_super_block *disk_super = root->fs_info->disk_super;
+
+        buf->f_namelen = BTRFS_NAME_LEN;
+        buf->f_blocks = btrfs_super_total_blocks(disk_super);
+        buf->f_bfree = buf->f_blocks - btrfs_super_blocks_used(disk_super);
+        buf->f_bavail = buf->f_bfree;
+        buf->f_bsize = dentry->d_sb->s_blocksize;
+        buf->f_type = BTRFS_SUPER_MAGIC;
+        return 0;
+}
 static struct file_system_type btrfs_fs_type = {
         .owner          = THIS_MODULE,
         .name           = "btrfs",
@@ -2362,7 +2396,6 @@ static struct file_system_type btrfs_fs_type = {
 };
 
 static struct super_operations btrfs_super_ops = {
-        .statfs         = simple_statfs,
         .delete_inode   = btrfs_delete_inode,
         .put_super      = btrfs_put_super,
         .read_inode     = btrfs_read_locked_inode,
@@ -2371,6 +2404,7 @@ static struct super_operations btrfs_super_ops = {
         .write_inode    = btrfs_write_inode,
         .alloc_inode    = btrfs_alloc_inode,
         .destroy_inode  = btrfs_destroy_inode,
+        .statfs         = btrfs_statfs,
 };
 
 static struct inode_operations btrfs_dir_inode_operations = {
@@ -2413,6 +2447,7 @@ static struct file_operations btrfs_file_operations = {
         .mmap           = generic_file_mmap,
         .open           = generic_file_open,
         .ioctl          = btrfs_ioctl,
+        .fsync          = btrfs_sync_file,
 };
 
 static int __init init_btrfs_fs(void)