Miao Xie
2013-Jan-10 12:43 UTC
[PATCH 01/11] Btrfs: use atomic for btrfs_fs_info->generation
fs_info->generation is a 64bit variant, we might get a wrong number on
the 32bit machines if there is no lock or other methods to protect it.
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
---
fs/btrfs/ctree.c | 7 ++++---
fs/btrfs/ctree.h | 2 +-
fs/btrfs/disk-io.c | 8 ++++----
fs/btrfs/file.c | 6 ++++--
fs/btrfs/inode.c | 5 +++--
fs/btrfs/qgroup.c | 2 +-
fs/btrfs/transaction.c | 4 ++--
include/trace/events/btrfs.h | 3 ++-
8 files changed, 21 insertions(+), 16 deletions(-)
diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index c7b67cf..dd57ce2 100644
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -1365,10 +1365,11 @@ noinline int btrfs_cow_block(struct btrfs_trans_handle
*trans,
(unsigned long long)
root->fs_info->running_transaction->transid);
- if (trans->transid != root->fs_info->generation)
+ if (trans->transid != atomic64_read(&root->fs_info->generation))
WARN(1, KERN_CRIT "trans %llu running %llu\n",
(unsigned long long)trans->transid,
- (unsigned long long)root->fs_info->generation);
+ (unsigned long long)atomic64_read(
+ &root->fs_info->generation));
if (!should_cow_block(trans, root, buf)) {
*cow_ret = buf;
@@ -1465,7 +1466,7 @@ int btrfs_realloc_node(struct btrfs_trans_handle *trans,
return 0;
WARN_ON(trans->transaction != root->fs_info->running_transaction);
- WARN_ON(trans->transid != root->fs_info->generation);
+ WARN_ON(trans->transid !=
atomic64_read(&root->fs_info->generation));
parent_nritems = btrfs_header_nritems(parent);
blocksize = btrfs_level_size(root, parent_level - 1);
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 547b7b0..c3edb22 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -1278,7 +1278,7 @@ struct btrfs_fs_info {
struct btrfs_block_rsv empty_block_rsv;
- u64 generation;
+ atomic64_t generation;
u64 last_trans_committed;
/*
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 4438aac..2d69541 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -1200,7 +1200,7 @@ static void __setup_root(u32 nodesize, u32 leafsize, u32
sectorsize,
memset(&root->root_item, 0, sizeof(root->root_item));
memset(&root->defrag_progress, 0, sizeof(root->defrag_progress));
memset(&root->root_kobj, 0, sizeof(root->root_kobj));
- root->defrag_trans_start = fs_info->generation;
+ root->defrag_trans_start = atomic64_read(&fs_info->generation);
init_completion(&root->kobj_unregister);
root->defrag_running = 0;
root->root_key.objectid = objectid;
@@ -2501,7 +2501,7 @@ retry_root_backup:
fs_info->pending_quota_state = 1;
}
- fs_info->generation = generation;
+ atomic64_set(&fs_info->generation, generation);
fs_info->last_trans_committed = generation;
ret = btrfs_recover_balance(fs_info);
@@ -3436,12 +3436,12 @@ void btrfs_mark_buffer_dirty(struct extent_buffer *buf)
int was_dirty;
btrfs_assert_tree_locked(buf);
- if (transid != root->fs_info->generation)
+ if (transid != atomic64_read(&root->fs_info->generation))
WARN(1, KERN_CRIT "btrfs transid mismatch buffer %llu, "
"found %llu running %llu\n",
(unsigned long long)buf->start,
(unsigned long long)transid,
- (unsigned long long)root->fs_info->generation);
+ (u64)atomic64_read(&root->fs_info->generation));
was_dirty = set_extent_buffer_dirty(buf);
if (!was_dirty) {
spin_lock(&root->fs_info->delalloc_lock);
diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index 20452c1..024246b 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -1588,7 +1588,8 @@ static ssize_t btrfs_file_aio_write(struct kiocb *iocb,
* otherwise subsequent syncs to a file that''s been synced in this
* transaction will appear to have already occured.
*/
- BTRFS_I(inode)->last_trans = root->fs_info->generation + 1;
+ BTRFS_I(inode)->last_trans =
atomic64_read(&root->fs_info->generation) +
+ 1;
BTRFS_I(inode)->last_sub_trans = root->log_transid;
if (num_written > 0 || num_written == -EIOCBQUEUED) {
err = generic_write_sync(file, pos, num_written);
@@ -1679,7 +1680,8 @@ int btrfs_sync_file(struct file *file, loff_t start,
loff_t end, int datasync)
* syncing
*/
smp_mb();
- if (btrfs_inode_in_log(inode, root->fs_info->generation) ||
+ if (btrfs_inode_in_log(inode,
+ atomic64_read(&root->fs_info->generation)) ||
BTRFS_I(inode)->last_trans <
root->fs_info->last_trans_committed) {
BTRFS_I(inode)->last_trans = 0;
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 2a2b5e1..aadb0db 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -2632,7 +2632,8 @@ static void btrfs_read_locked_inode(struct inode *inode)
* idea about which extents were modified before we were evicted from
* cache.
*/
- if (BTRFS_I(inode)->last_trans == root->fs_info->generation)
+ if (BTRFS_I(inode)->last_trans =+
atomic64_read(&root->fs_info->generation))
set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
&BTRFS_I(inode)->runtime_flags);
@@ -6852,7 +6853,7 @@ again:
set_page_dirty(page);
SetPageUptodate(page);
- BTRFS_I(inode)->last_trans = root->fs_info->generation;
+ BTRFS_I(inode)->last_trans =
atomic64_read(&root->fs_info->generation);
BTRFS_I(inode)->last_sub_trans = BTRFS_I(inode)->root->log_transid;
BTRFS_I(inode)->last_log_commit =
BTRFS_I(inode)->root->last_log_commit;
diff --git a/fs/btrfs/qgroup.c b/fs/btrfs/qgroup.c
index fe9d02c..8bed26b 100644
--- a/fs/btrfs/qgroup.c
+++ b/fs/btrfs/qgroup.c
@@ -290,7 +290,7 @@ int btrfs_read_qgroup_config(struct btrfs_fs_info *fs_info)
goto out;
}
if (btrfs_qgroup_status_generation(l, ptr) !- fs_info->generation)
{
+ atomic64_read(&fs_info->generation)) {
flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
printk(KERN_ERR
"btrfs: qgroup generation mismatch, "
diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index 87fac9a..e7992ca 100644
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -161,8 +161,8 @@ loop:
list_add_tail(&cur_trans->list, &fs_info->trans_list);
extent_io_tree_init(&cur_trans->dirty_pages,
fs_info->btree_inode->i_mapping);
- fs_info->generation++;
- cur_trans->transid = fs_info->generation;
+ atomic64_inc(&fs_info->generation);
+ cur_trans->transid = atomic64_read(&fs_info->generation);
fs_info->running_transaction = cur_trans;
cur_trans->aborted = 0;
spin_unlock(&fs_info->trans_lock);
diff --git a/include/trace/events/btrfs.h b/include/trace/events/btrfs.h
index ea546a4..09dc72f 100644
--- a/include/trace/events/btrfs.h
+++ b/include/trace/events/btrfs.h
@@ -71,7 +71,8 @@ TRACE_EVENT(btrfs_transaction_commit,
),
TP_fast_assign(
- __entry->generation = root->fs_info->generation;
+ __entry->generation +
atomic64_read(&root->fs_info->generation);
__entry->root_objectid = root->root_key.objectid;
),
--
1.7.11.7
--
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