CIFS: Fix SMB2+ interim response processing for read requests

[firefly-linux-kernel-4.4.55.git] / fs / fs-writeback.c

diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index 023f6a1f23cd034810aa26acde809cde118841f2..e5232bbcbe3d40ec585c25351de34935671e8667 100644 (file)
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -317,6 +317,7 @@ static void inode_switch_wbs_work_fn(struct work_struct *work)
        struct inode_switch_wbs_context *isw =
                container_of(work, struct inode_switch_wbs_context, work);
        struct inode *inode = isw->inode;
+       struct super_block *sb = inode->i_sb;
        struct address_space *mapping = inode->i_mapping;
        struct bdi_writeback *old_wb = inode->i_wb;
        struct bdi_writeback *new_wb = isw->new_wb;
@@ -423,6 +424,7 @@ skip_switch:
        wb_put(new_wb);
 
        iput(inode);
+       deactivate_super(sb);
        kfree(isw);
 }
 
@@ -469,11 +471,14 @@ static void inode_switch_wbs(struct inode *inode, int new_wb_id)
 
        /* while holding I_WB_SWITCH, no one else can update the association */
        spin_lock(&inode->i_lock);
+
        if (inode->i_state & (I_WB_SWITCH | I_FREEING) ||
-           inode_to_wb(inode) == isw->new_wb) {
-               spin_unlock(&inode->i_lock);
-               goto out_free;
-       }
+           inode_to_wb(inode) == isw->new_wb)
+               goto out_unlock;
+
+       if (!atomic_inc_not_zero(&inode->i_sb->s_active))
+               goto out_unlock;
+
        inode->i_state |= I_WB_SWITCH;
        spin_unlock(&inode->i_lock);
 
@@ -489,6 +494,8 @@ static void inode_switch_wbs(struct inode *inode, int new_wb_id)
        call_rcu(&isw->rcu_head, inode_switch_wbs_rcu_fn);
        return;
 
+out_unlock:
+       spin_unlock(&inode->i_lock);
 out_free:
        if (isw->new_wb)
                wb_put(isw->new_wb);