Btrfs: check to see if root_list is empty before adding it to dead roots

[linux-imx.git] / fs / btrfs / transaction.h

diff --git a/fs/btrfs/transaction.h b/fs/btrfs/transaction.h
index 24c97335a59ffe061b0df684baeb69837aa75c77..defbc426989787e405e69f6e360fa82b3dc26556 100644 (file)
--- a/fs/btrfs/transaction.h
+++ b/fs/btrfs/transaction.h
@@ -22,8 +22,24 @@
 #include "delayed-ref.h"
 #include "ctree.h"
 
+enum btrfs_trans_state {
+       TRANS_STATE_RUNNING             = 0,
+       TRANS_STATE_BLOCKED             = 1,
+       TRANS_STATE_COMMIT_START        = 2,
+       TRANS_STATE_COMMIT_DOING        = 3,
+       TRANS_STATE_UNBLOCKED           = 4,
+       TRANS_STATE_COMPLETED           = 5,
+       TRANS_STATE_MAX                 = 6,
+};
+
 struct btrfs_transaction {
        u64 transid;
+       /*
+        * total external writers(USERSPACE/START/ATTACH) in this
+        * transaction, it must be zero before the transaction is
+        * being committed
+        */
+       atomic_t num_extwriters;
        /*
         * total writers in this transaction, it must be zero before the
         * transaction can end
@@ -31,12 +47,8 @@ struct btrfs_transaction {
        atomic_t num_writers;
        atomic_t use_count;
 
-       unsigned long num_joined;
-
-       spinlock_t commit_lock;
-       int in_commit;
-       int commit_done;
-       int blocked;
+       /* Be protected by fs_info->trans_lock when we want to change it. */
+       enum btrfs_trans_state state;
        struct list_head list;
        struct extent_io_tree dirty_pages;
        unsigned long start_time;
@@ -44,17 +56,27 @@ struct btrfs_transaction {
        wait_queue_head_t commit_wait;
        struct list_head pending_snapshots;
        struct list_head ordered_operations;
+       struct list_head pending_chunks;
        struct btrfs_delayed_ref_root delayed_refs;
        int aborted;
 };
 
-enum btrfs_trans_type {
-       TRANS_START,
-       TRANS_JOIN,
-       TRANS_USERSPACE,
-       TRANS_JOIN_NOLOCK,
-       TRANS_ATTACH,
-};
+#define __TRANS_FREEZABLE      (1U << 0)
+
+#define __TRANS_USERSPACE      (1U << 8)
+#define __TRANS_START          (1U << 9)
+#define __TRANS_ATTACH         (1U << 10)
+#define __TRANS_JOIN           (1U << 11)
+#define __TRANS_JOIN_NOLOCK    (1U << 12)
+
+#define TRANS_USERSPACE                (__TRANS_USERSPACE | __TRANS_FREEZABLE)
+#define TRANS_START            (__TRANS_START | __TRANS_FREEZABLE)
+#define TRANS_ATTACH           (__TRANS_ATTACH)
+#define TRANS_JOIN             (__TRANS_JOIN | __TRANS_FREEZABLE)
+#define TRANS_JOIN_NOLOCK      (__TRANS_JOIN_NOLOCK)
+
+#define TRANS_EXTWRITERS       (__TRANS_USERSPACE | __TRANS_START |    \
+                                __TRANS_ATTACH)
 
 struct btrfs_trans_handle {
        u64 transid;
@@ -70,7 +92,7 @@ struct btrfs_trans_handle {
        short aborted;
        short adding_csums;
        bool allocating_chunk;
-       enum btrfs_trans_type type;
+       unsigned int type;
        /*
         * this root is only needed to validate that the root passed to
         * start_transaction is the same as the one passed to end_transaction.
@@ -121,7 +143,7 @@ int btrfs_wait_for_commit(struct btrfs_root *root, u64 transid);
 int btrfs_write_and_wait_transaction(struct btrfs_trans_handle *trans,
                                     struct btrfs_root *root);
 
-int btrfs_add_dead_root(struct btrfs_root *root);
+void btrfs_add_dead_root(struct btrfs_root *root);
 int btrfs_defrag_root(struct btrfs_root *root);
 int btrfs_clean_one_deleted_snapshot(struct btrfs_root *root);
 int btrfs_commit_transaction(struct btrfs_trans_handle *trans,