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-rw-r--r--fs/btrfs/ctree.c45
-rw-r--r--fs/btrfs/ctree.h10
-rw-r--r--fs/btrfs/disk-io.c46
-rw-r--r--fs/btrfs/disk-io.h10
-rw-r--r--fs/btrfs/extent-tree.c7
-rw-r--r--fs/btrfs/locking.c11
-rw-r--r--fs/btrfs/volumes.c2
7 files changed, 99 insertions, 32 deletions
diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index c8f4c54..42491d7 100644
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -62,14 +62,38 @@ noinline void btrfs_set_path_blocking(struct btrfs_path *p)
/*
* reset all the locked nodes in the patch to spinning locks.
+ *
+ * held is used to keep lockdep happy, when lockdep is enabled
+ * we set held to a blocking lock before we go around and
+ * retake all the spinlocks in the path. You can safely use NULL
+ * for held
*/
-noinline void btrfs_clear_path_blocking(struct btrfs_path *p)
+noinline void btrfs_clear_path_blocking(struct btrfs_path *p,
+ struct extent_buffer *held)
{
int i;
- for (i = 0; i < BTRFS_MAX_LEVEL; i++) {
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+ /* lockdep really cares that we take all of these spinlocks
+ * in the right order. If any of the locks in the path are not
+ * currently blocking, it is going to complain. So, make really
+ * really sure by forcing the path to blocking before we clear
+ * the path blocking.
+ */
+ if (held)
+ btrfs_set_lock_blocking(held);
+ btrfs_set_path_blocking(p);
+#endif
+
+ for (i = BTRFS_MAX_LEVEL - 1; i >= 0; i--) {
if (p->nodes[i] && p->locks[i])
btrfs_clear_lock_blocking(p->nodes[i]);
}
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+ if (held)
+ btrfs_clear_lock_blocking(held);
+#endif
}
/* this also releases the path */
@@ -279,7 +303,7 @@ static noinline int __btrfs_cow_block(struct btrfs_trans_handle *trans,
trans->transid, level, &ins);
BUG_ON(ret);
cow = btrfs_init_new_buffer(trans, root, prealloc_dest,
- buf->len);
+ buf->len, level);
} else {
cow = btrfs_alloc_free_block(trans, root, buf->len,
parent_start,
@@ -1559,7 +1583,7 @@ cow_done:
if (!p->skip_locking)
p->locks[level] = 1;
- btrfs_clear_path_blocking(p);
+ btrfs_clear_path_blocking(p, NULL);
/*
* we have a lock on b and as long as we aren't changing
@@ -1598,7 +1622,7 @@ cow_done:
btrfs_set_path_blocking(p);
sret = split_node(trans, root, p, level);
- btrfs_clear_path_blocking(p);
+ btrfs_clear_path_blocking(p, NULL);
BUG_ON(sret > 0);
if (sret) {
@@ -1618,7 +1642,7 @@ cow_done:
btrfs_set_path_blocking(p);
sret = balance_level(trans, root, p, level);
- btrfs_clear_path_blocking(p);
+ btrfs_clear_path_blocking(p, NULL);
if (sret) {
ret = sret;
@@ -1681,13 +1705,13 @@ cow_done:
if (!p->skip_locking) {
int lret;
- btrfs_clear_path_blocking(p);
+ btrfs_clear_path_blocking(p, NULL);
lret = btrfs_try_spin_lock(b);
if (!lret) {
btrfs_set_path_blocking(p);
btrfs_tree_lock(b);
- btrfs_clear_path_blocking(p);
+ btrfs_clear_path_blocking(p, b);
}
}
} else {
@@ -1699,7 +1723,7 @@ cow_done:
btrfs_set_path_blocking(p);
sret = split_leaf(trans, root, key,
p, ins_len, ret == 0);
- btrfs_clear_path_blocking(p);
+ btrfs_clear_path_blocking(p, NULL);
BUG_ON(sret > 0);
if (sret) {
@@ -3919,7 +3943,6 @@ find_next_key:
btrfs_release_path(root, path);
goto again;
} else {
- btrfs_clear_path_blocking(path);
goto out;
}
}
@@ -3939,7 +3962,7 @@ find_next_key:
path->locks[level - 1] = 1;
path->nodes[level - 1] = cur;
unlock_up(path, level, 1);
- btrfs_clear_path_blocking(path);
+ btrfs_clear_path_blocking(path, NULL);
}
out:
if (ret == 0)
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 3f7a805..766b31a 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -43,11 +43,7 @@ struct btrfs_ordered_sum;
#define BTRFS_ACL_NOT_CACHED ((void *)-1)
-#ifdef CONFIG_LOCKDEP
-# define BTRFS_MAX_LEVEL 7
-#else
-# define BTRFS_MAX_LEVEL 8
-#endif
+#define BTRFS_MAX_LEVEL 8
/* holds pointers to all of the tree roots */
#define BTRFS_ROOT_TREE_OBJECTID 1ULL
@@ -1715,7 +1711,8 @@ struct extent_buffer *btrfs_alloc_free_block(struct btrfs_trans_handle *trans,
u64 empty_size);
struct extent_buffer *btrfs_init_new_buffer(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
- u64 bytenr, u32 blocksize);
+ u64 bytenr, u32 blocksize,
+ int level);
int btrfs_alloc_extent(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
u64 num_bytes, u64 parent, u64 min_bytes,
@@ -1835,7 +1832,6 @@ void btrfs_release_path(struct btrfs_root *root, struct btrfs_path *p);
struct btrfs_path *btrfs_alloc_path(void);
void btrfs_free_path(struct btrfs_path *p);
void btrfs_set_path_blocking(struct btrfs_path *p);
-void btrfs_clear_path_blocking(struct btrfs_path *p);
void btrfs_unlock_up_safe(struct btrfs_path *p, int level);
int btrfs_del_items(struct btrfs_trans_handle *trans, struct btrfs_root *root,
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 5aebddd..adda739 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -75,6 +75,40 @@ struct async_submit_bio {
struct btrfs_work work;
};
+/* These are used to set the lockdep class on the extent buffer locks.
+ * The class is set by the readpage_end_io_hook after the buffer has
+ * passed csum validation but before the pages are unlocked.
+ *
+ * The lockdep class is also set by btrfs_init_new_buffer on freshly
+ * allocated blocks.
+ *
+ * The class is based on the level in the tree block, which allows lockdep
+ * to know that lower nodes nest inside the locks of higher nodes.
+ *
+ * We also add a check to make sure the highest level of the tree is
+ * the same as our lockdep setup here. If BTRFS_MAX_LEVEL changes, this
+ * code needs update as well.
+ */
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+# if BTRFS_MAX_LEVEL != 8
+# error
+# endif
+static struct lock_class_key btrfs_eb_class[BTRFS_MAX_LEVEL + 1];
+static const char *btrfs_eb_name[BTRFS_MAX_LEVEL + 1] = {
+ /* leaf */
+ "btrfs-extent-00",
+ "btrfs-extent-01",
+ "btrfs-extent-02",
+ "btrfs-extent-03",
+ "btrfs-extent-04",
+ "btrfs-extent-05",
+ "btrfs-extent-06",
+ "btrfs-extent-07",
+ /* highest possible level */
+ "btrfs-extent-08",
+};
+#endif
+
/*
* extents on the btree inode are pretty simple, there's one extent
* that covers the entire device
@@ -347,6 +381,15 @@ static int check_tree_block_fsid(struct btrfs_root *root,
return ret;
}
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+void btrfs_set_buffer_lockdep_class(struct extent_buffer *eb, int level)
+{
+ lockdep_set_class_and_name(&eb->lock,
+ &btrfs_eb_class[level],
+ btrfs_eb_name[level]);
+}
+#endif
+
static int btree_readpage_end_io_hook(struct page *page, u64 start, u64 end,
struct extent_state *state)
{
@@ -392,6 +435,8 @@ static int btree_readpage_end_io_hook(struct page *page, u64 start, u64 end,
}
found_level = btrfs_header_level(eb);
+ btrfs_set_buffer_lockdep_class(eb, found_level);
+
ret = csum_tree_block(root, eb, 1);
if (ret)
ret = -EIO;
@@ -1777,7 +1822,6 @@ struct btrfs_root *open_ctree(struct super_block *sb,
ret = find_and_setup_root(tree_root, fs_info,
BTRFS_DEV_TREE_OBJECTID, dev_root);
dev_root->track_dirty = 1;
-
if (ret)
goto fail_extent_root;
diff --git a/fs/btrfs/disk-io.h b/fs/btrfs/disk-io.h
index 494a56e..95029db 100644
--- a/fs/btrfs/disk-io.h
+++ b/fs/btrfs/disk-io.h
@@ -101,4 +101,14 @@ int btrfs_init_log_root_tree(struct btrfs_trans_handle *trans,
int btrfs_add_log_tree(struct btrfs_trans_handle *trans,
struct btrfs_root *root);
int btree_lock_page_hook(struct page *page);
+
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+void btrfs_set_buffer_lockdep_class(struct extent_buffer *eb, int level);
+#else
+static inline void btrfs_set_buffer_lockdep_class(struct extent_buffer *eb,
+ int level)
+{
+}
+#endif
#endif
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index c59e120..cd86bff 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -3416,7 +3416,8 @@ int btrfs_alloc_extent(struct btrfs_trans_handle *trans,
struct extent_buffer *btrfs_init_new_buffer(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
- u64 bytenr, u32 blocksize)
+ u64 bytenr, u32 blocksize,
+ int level)
{
struct extent_buffer *buf;
@@ -3424,6 +3425,7 @@ struct extent_buffer *btrfs_init_new_buffer(struct btrfs_trans_handle *trans,
if (!buf)
return ERR_PTR(-ENOMEM);
btrfs_set_header_generation(buf, trans->transid);
+ btrfs_set_buffer_lockdep_class(buf, level);
btrfs_tree_lock(buf);
clean_tree_block(trans, root, buf);
@@ -3467,7 +3469,8 @@ struct extent_buffer *btrfs_alloc_free_block(struct btrfs_trans_handle *trans,
return ERR_PTR(ret);
}
- buf = btrfs_init_new_buffer(trans, root, ins.objectid, blocksize);
+ buf = btrfs_init_new_buffer(trans, root, ins.objectid,
+ blocksize, level);
return buf;
}
diff --git a/fs/btrfs/locking.c b/fs/btrfs/locking.c
index 9ebe938..85506c4 100644
--- a/fs/btrfs/locking.c
+++ b/fs/btrfs/locking.c
@@ -25,21 +25,10 @@
#include "extent_io.h"
#include "locking.h"
-/*
- * btrfs_header_level() isn't free, so don't call it when lockdep isn't
- * on
- */
-#ifdef CONFIG_DEBUG_LOCK_ALLOC
-static inline void spin_nested(struct extent_buffer *eb)
-{
- spin_lock_nested(&eb->lock, BTRFS_MAX_LEVEL - btrfs_header_level(eb));
-}
-#else
static inline void spin_nested(struct extent_buffer *eb)
{
spin_lock(&eb->lock);
}
-#endif
/*
* Setting a lock to blocking will drop the spinlock and set the
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index c793b6f..1316139 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -3102,6 +3102,8 @@ int btrfs_read_sys_array(struct btrfs_root *root)
if (!sb)
return -ENOMEM;
btrfs_set_buffer_uptodate(sb);
+ btrfs_set_buffer_lockdep_class(sb, 0);
+
write_extent_buffer(sb, super_copy, 0, BTRFS_SUPER_INFO_SIZE);
array_size = btrfs_super_sys_array_size(super_copy);
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