Btrfs: Implement generation numbers in block pointers
Signed-off-by: Chris Mason <chris.mason@oracle.com>
diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index 3b16051..5697705 100644
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -114,6 +114,9 @@
} else {
btrfs_set_node_blockptr(parent, parent_slot,
cow->start);
+ WARN_ON(trans->transid == 0);
+ btrfs_set_node_ptr_generation(parent, parent_slot,
+ trans->transid);
btrfs_mark_buffer_dirty(parent);
WARN_ON(btrfs_header_generation(parent) != trans->transid);
btrfs_free_extent(trans, root, buf->start, buf->len, 1);
@@ -967,6 +970,7 @@
{
struct extent_buffer *b;
u64 bytenr;
+ u64 ptr_gen;
int slot;
int ret;
int level;
@@ -1031,10 +1035,18 @@
if (level == lowest_level)
break;
bytenr = btrfs_node_blockptr(b, slot);
+ ptr_gen = btrfs_node_ptr_generation(b, slot);
if (should_reada)
reada_for_search(root, p, level, slot);
b = read_tree_block(root, bytenr,
btrfs_level_size(root, level - 1));
+ if (ptr_gen != btrfs_header_generation(b)) {
+ printk("block %llu bad gen wanted %llu "
+ "found %llu\n",
+ (unsigned long long)b->start,
+ (unsigned long long)ptr_gen,
+ (unsigned long long)btrfs_header_generation(b));
+ }
} else {
p->slots[level] = slot;
if (ins_len > 0 && btrfs_leaf_free_space(root, b) <
@@ -1218,6 +1230,8 @@
btrfs_node_key(lower, &lower_key, 0);
btrfs_set_node_key(c, &lower_key, 0);
btrfs_set_node_blockptr(c, 0, lower->start);
+ WARN_ON(btrfs_header_generation(lower) == 0);
+ btrfs_set_node_ptr_generation(c, 0, btrfs_header_generation(lower));
btrfs_mark_buffer_dirty(c);
@@ -1261,6 +1275,8 @@
}
btrfs_set_node_key(lower, key, slot);
btrfs_set_node_blockptr(lower, slot, bytenr);
+ WARN_ON(trans->transid == 0);
+ btrfs_set_node_ptr_generation(lower, slot, trans->transid);
btrfs_set_header_nritems(lower, nritems + 1);
btrfs_mark_buffer_dirty(lower);
return 0;
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 9bc1b0a..fd58dd84 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -110,7 +110,7 @@
#define BTRFS_MAX_LEVEL 8
#define BTRFS_NODEPTRS_PER_BLOCK(r) (((r)->nodesize - \
sizeof(struct btrfs_header)) / \
- (sizeof(struct btrfs_disk_key) + sizeof(u64)))
+ sizeof(struct btrfs_key_ptr))
#define __BTRFS_LEAF_DATA_SIZE(bs) ((bs) - sizeof(struct btrfs_header))
#define BTRFS_LEAF_DATA_SIZE(r) (__BTRFS_LEAF_DATA_SIZE(r->leafsize))
#define BTRFS_MAX_INLINE_DATA_SIZE(r) (BTRFS_LEAF_DATA_SIZE(r) - \
@@ -168,6 +168,7 @@
struct btrfs_key_ptr {
struct btrfs_disk_key key;
__le64 blockptr;
+ __le64 generation;
} __attribute__ ((__packed__));
struct btrfs_node {
@@ -196,7 +197,13 @@
*/
struct btrfs_extent_item {
__le32 refs;
- __le64 owner;
+} __attribute__ ((__packed__));
+
+struct btrfs_extent_ref {
+ __le64 root;
+ __le64 generation;
+ __le64 objectid;
+ __le64 offset;
} __attribute__ ((__packed__));
struct btrfs_inode_timespec {
@@ -402,12 +409,13 @@
* are used, and how many references there are to each block
*/
#define BTRFS_EXTENT_ITEM_KEY 33
+#define BTRFS_EXTENT_REF_KEY 34
/*
* block groups give us hints into the extent allocation trees. Which
* blocks are free etc etc
*/
-#define BTRFS_BLOCK_GROUP_ITEM_KEY 34
+#define BTRFS_BLOCK_GROUP_ITEM_KEY 50
/*
* string items are for debugging. They just store a short string of
@@ -529,15 +537,25 @@
/* struct btrfs_extent_item */
BTRFS_SETGET_FUNCS(extent_refs, struct btrfs_extent_item, refs, 32);
-BTRFS_SETGET_FUNCS(extent_owner, struct btrfs_extent_item, owner, 64);
+
+/* struct btrfs_extent_ref */
+BTRFS_SETGET_FUNCS(ref_root, struct btrfs_extent_ref, root, 64);
+BTRFS_SETGET_FUNCS(ref_generation, struct btrfs_extent_ref, generation, 64);
+BTRFS_SETGET_FUNCS(ref_objectid, struct btrfs_extent_ref, objectid, 64);
+BTRFS_SETGET_FUNCS(ref_offset, struct btrfs_extent_ref, offset, 64);
+
+BTRFS_SETGET_STACK_FUNCS(ref_root, struct btrfs_extent_ref, root, 64);
+BTRFS_SETGET_STACK_FUNCS(ref_generation, struct btrfs_extent_ref,
+ generation, 64);
+BTRFS_SETGET_STACK_FUNCS(ref_objectid, struct btrfs_extent_ref, objectid, 64);
+BTRFS_SETGET_STACK_FUNCS(ref_offset, struct btrfs_extent_ref, offset, 64);
BTRFS_SETGET_STACK_FUNCS(stack_extent_refs, struct btrfs_extent_item,
refs, 32);
-BTRFS_SETGET_STACK_FUNCS(stack_extent_owner, struct btrfs_extent_item,
- owner, 64);
/* struct btrfs_node */
BTRFS_SETGET_FUNCS(key_blockptr, struct btrfs_key_ptr, blockptr, 64);
+BTRFS_SETGET_FUNCS(key_generation, struct btrfs_key_ptr, generation, 64);
static inline u64 btrfs_node_blockptr(struct extent_buffer *eb, int nr)
{
@@ -556,6 +574,23 @@
btrfs_set_key_blockptr(eb, (struct btrfs_key_ptr *)ptr, val);
}
+static inline u64 btrfs_node_ptr_generation(struct extent_buffer *eb, int nr)
+{
+ unsigned long ptr;
+ ptr = offsetof(struct btrfs_node, ptrs) +
+ sizeof(struct btrfs_key_ptr) * nr;
+ return btrfs_key_generation(eb, (struct btrfs_key_ptr *)ptr);
+}
+
+static inline void btrfs_set_node_ptr_generation(struct extent_buffer *eb,
+ int nr, u64 val)
+{
+ unsigned long ptr;
+ ptr = offsetof(struct btrfs_node, ptrs) +
+ sizeof(struct btrfs_key_ptr) * nr;
+ btrfs_set_key_generation(eb, (struct btrfs_key_ptr *)ptr, val);
+}
+
static inline unsigned long btrfs_node_key_ptr_offset(int nr)
{
return offsetof(struct btrfs_node, ptrs) +
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 8ab4954..0f1ebdd 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -17,6 +17,7 @@
*/
#include <linux/sched.h>
+#include "hash.h"
#include "ctree.h"
#include "disk-io.h"
#include "print-tree.h"
@@ -352,9 +353,63 @@
return found_group;
}
+static u64 hash_extent_ref(u64 root_objectid, u64 root_generation,
+ u64 owner, u64 owner_offset)
+{
+ u32 high_crc = ~(u32)0;
+ u32 low_crc = ~(u32)0;
+ __le64 lenum;
+
+ lenum = cpu_to_le64(root_objectid);
+ high_crc = crc32c(high_crc, &lenum, sizeof(lenum));
+ lenum = cpu_to_le64(root_generation);
+ high_crc = crc32c(high_crc, &lenum, sizeof(lenum));
+
+ lenum = cpu_to_le64(owner);
+ low_crc = crc32c(low_crc, &lenum, sizeof(lenum));
+
+ lenum = cpu_to_le64(owner_offset);
+ low_crc = crc32c(low_crc, &lenum, sizeof(lenum));
+
+ return ((u64)high_crc << 32) | (u64)low_crc;
+}
+
+int insert_extent_ref(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct btrfs_path *path,
+ u64 bytenr,
+ u64 root_objectid, u64 root_generation,
+ u64 owner, u64 owner_offset)
+{
+ u64 hash;
+ struct btrfs_key key;
+ struct btrfs_extent_ref ref;
+ struct extent_buffer *l;
+ struct btrfs_extent_item *item;
+ int ret;
+
+ btrfs_set_stack_ref_root(&ref, root_objectid);
+ btrfs_set_stack_ref_generation(&ref, root_generation);
+ btrfs_set_stack_ref_objectid(&ref, owner);
+ btrfs_set_stack_ref_offset(&ref, owner_offset);
+
+ ret = btrfs_name_hash(&ref, sizeof(ref), &hash);
+ key.offset = hash;
+ key.objectid = bytenr;
+ key.type = BTRFS_EXTENT_REF_KEY;
+
+ ret = btrfs_insert_empty_item(trans, root, path, &key, sizeof(ref));
+ while (ret == -EEXIST) {
+
+ }
+
+}
+
int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
- u64 bytenr, u64 num_bytes)
+ u64 bytenr, u64 num_bytes,
+ u64 root_objectid, u64 root_generation,
+ u64 owner, u64 owner_offset)
{
struct btrfs_path *path;
int ret;
@@ -386,9 +441,10 @@
btrfs_mark_buffer_dirty(path->nodes[0]);
btrfs_release_path(root->fs_info->extent_root, path);
- btrfs_free_path(path);
finish_current_insert(trans, root->fs_info->extent_root);
del_pending_extents(trans, root->fs_info->extent_root);
+
+ btrfs_free_path(path);
return 0;
}