Btrfs: still corruption hunting

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

1 files changed, 27 insertions, 12 deletions

diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index 84c4e278ce2e..72b52e1e0b1b 100644
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -5,13 +5,20 @@
 #include "transaction.h"
 
 static int total_trans = 0;
+extern struct kmem_cache *btrfs_trans_handle_cachep;
+extern struct kmem_cache *btrfs_transaction_cachep;
+
+#define TRANS_MAGIC 0xE1E10E
 static void put_transaction(struct btrfs_transaction *transaction)
 {
+        WARN_ON(transaction->use_count == 0);
         transaction->use_count--;
+        WARN_ON(transaction->magic != TRANS_MAGIC);
         if (transaction->use_count == 0) {
                 WARN_ON(total_trans == 0);
                 total_trans--;
-                kfree(transaction);
+                memset(transaction, 0, sizeof(*transaction));
+                kmem_cache_free(btrfs_transaction_cachep, transaction);
         }
 }
 
@@ -20,7 +27,8 @@ static int join_transaction(struct btrfs_root *root)
         struct btrfs_transaction *cur_trans;
         cur_trans = root->fs_info->running_transaction;
         if (!cur_trans) {
-                cur_trans = kmalloc(sizeof(*cur_trans), GFP_NOFS);
+                cur_trans = kmem_cache_alloc(btrfs_transaction_cachep,
+                                             GFP_NOFS);
                 total_trans++;
                 BUG_ON(!cur_trans);
                 root->fs_info->running_transaction = cur_trans;
@@ -28,6 +36,7 @@ static int join_transaction(struct btrfs_root *root)
                 cur_trans->transid = root->root_key.offset + 1;
                 init_waitqueue_head(&cur_trans->writer_wait);
                 init_waitqueue_head(&cur_trans->commit_wait);
+                cur_trans->magic = TRANS_MAGIC;
                 cur_trans->in_commit = 0;
                 cur_trans->use_count = 1;
                 cur_trans->commit_done = 0;
@@ -39,7 +48,8 @@ static int join_transaction(struct btrfs_root *root)
 struct btrfs_trans_handle *btrfs_start_transaction(struct btrfs_root *root,
                                                    int num_blocks)
 {
-        struct btrfs_trans_handle *h = kmalloc(sizeof(*h), GFP_NOFS);
+        struct btrfs_trans_handle *h =
+                kmem_cache_alloc(btrfs_trans_handle_cachep, GFP_NOFS);
         int ret;
 
         mutex_lock(&root->fs_info->trans_mutex);
@@ -51,6 +61,7 @@ struct btrfs_trans_handle *btrfs_start_transaction(struct btrfs_root *root,
         h->blocks_used = 0;
         root->fs_info->running_transaction->use_count++;
         mutex_unlock(&root->fs_info->trans_mutex);
+        h->magic = h->magic2 = TRANS_MAGIC;
         return h;
 }
 
@@ -58,6 +69,8 @@ int btrfs_end_transaction(struct btrfs_trans_handle *trans,
                           struct btrfs_root *root)
 {
         struct btrfs_transaction *cur_trans;
+        WARN_ON(trans->magic != TRANS_MAGIC);
+        WARN_ON(trans->magic2 != TRANS_MAGIC);
         mutex_lock(&root->fs_info->trans_mutex);
         cur_trans = root->fs_info->running_transaction;
         WARN_ON(cur_trans->num_writers < 1);
@@ -67,7 +80,7 @@ int btrfs_end_transaction(struct btrfs_trans_handle *trans,
         put_transaction(cur_trans);
         mutex_unlock(&root->fs_info->trans_mutex);
         memset(trans, 0, sizeof(*trans));
-        kfree(trans);
+        kmem_cache_free(btrfs_trans_handle_cachep, trans);
         return 0;
 }
 
@@ -75,7 +88,7 @@ int btrfs_end_transaction(struct btrfs_trans_handle *trans,
 int btrfs_write_and_wait_transaction(struct btrfs_trans_handle *trans,
                                      struct btrfs_root *root)
 {
-        filemap_write_and_wait(root->fs_info->btree_inode->i_mapping);
+        filemap_write_and_wait(root->fs_info->sb->s_bdev->bd_inode->i_mapping);
         return 0;
 }
 
@@ -137,6 +150,7 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
 
         mutex_lock(&root->fs_info->trans_mutex);
         if (trans->transaction->in_commit) {
+printk("already in commit!, waiting\n");
                 cur_trans = trans->transaction;
                 trans->transaction->use_count++;
                 btrfs_end_transaction(trans, root);
@@ -146,7 +160,10 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
                 mutex_unlock(&root->fs_info->trans_mutex);
                 return 0;
         }
+        cur_trans = trans->transaction;
+        trans->transaction->in_commit = 1;
         while (trans->transaction->num_writers > 1) {
+                WARN_ON(cur_trans != trans->transaction);
                 prepare_to_wait(&trans->transaction->writer_wait, &wait,
                                 TASK_UNINTERRUPTIBLE);
                 if (trans->transaction->num_writers <= 1)
@@ -154,15 +171,15 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
                 mutex_unlock(&root->fs_info->trans_mutex);
                 schedule();
                 mutex_lock(&root->fs_info->trans_mutex);
+                finish_wait(&trans->transaction->writer_wait, &wait);
         }
         finish_wait(&trans->transaction->writer_wait, &wait);
-
+        WARN_ON(cur_trans != trans->transaction);
         if (root->node != root->commit_root) {
                 memcpy(&snap_key, &root->root_key, sizeof(snap_key));
                 root->root_key.offset++;
         }
 
-
         if (btrfs_root_blocknr(&root->root_item) != root->node->b_blocknr) {
                 btrfs_set_root_blocknr(&root->root_item, root->node->b_blocknr);
                 ret = btrfs_insert_root(trans, root->fs_info->tree_root,
@@ -172,22 +189,21 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
 
         ret = btrfs_commit_tree_roots(trans, root);
         BUG_ON(ret);
-
         cur_trans = root->fs_info->running_transaction;
         root->fs_info->running_transaction = NULL;
         mutex_unlock(&root->fs_info->trans_mutex);
-
         ret = btrfs_write_and_wait_transaction(trans, root);
         BUG_ON(ret);
 
         write_ctree_super(trans, root);
         btrfs_finish_extent_commit(trans, root);
         mutex_lock(&root->fs_info->trans_mutex);
+        cur_trans->commit_done = 1;
+        wake_up(&cur_trans->commit_wait);
         put_transaction(cur_trans);
         put_transaction(cur_trans);
         mutex_unlock(&root->fs_info->trans_mutex);
-        kfree(trans);
-
+        kmem_cache_free(btrfs_trans_handle_cachep, trans);
         if (root->node != root->commit_root) {
                 trans = btrfs_start_transaction(root, 1);
                 snap = root->commit_root;
@@ -203,7 +219,6 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
                 ret = btrfs_end_transaction(trans, root);
                 BUG_ON(ret);
         }
-
         return ret;
 }