@@ -753,6 +753,104 @@ int btrfs_ensure_empty_zones(struct btrfs_device *device, u64 start, u64 size)
return 0;
}
+static int emulate_write_pointer(struct btrfs_block_group *cache,
+ u64 *offset_ret)
+{
+ struct btrfs_fs_info *fs_info = cache->fs_info;
+ struct btrfs_root *root = fs_info->extent_root;
+ struct btrfs_path *path;
+ struct extent_buffer *leaf;
+ struct btrfs_key search_key;
+ struct btrfs_key found_key;
+ int slot;
+ int ret;
+ u64 length;
+
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
+
+ search_key.objectid = cache->start + cache->length;
+ search_key.type = 0;
+ search_key.offset = 0;
+
+ ret = btrfs_search_slot(NULL, root, &search_key, path, 0, 0);
+ if (ret < 0)
+ goto out;
+ ASSERT(ret != 0);
+ slot = path->slots[0];
+ leaf = path->nodes[0];
+ ASSERT(slot != 0);
+ slot--;
+ btrfs_item_key_to_cpu(leaf, &found_key, slot);
+
+ if (found_key.objectid < cache->start) {
+ *offset_ret = 0;
+ } else if (found_key.type == BTRFS_BLOCK_GROUP_ITEM_KEY) {
+ struct btrfs_key extent_item_key;
+
+ if (found_key.objectid != cache->start) {
+ ret = -EUCLEAN;
+ goto out;
+ }
+
+ length = 0;
+
+ /* metadata may have METADATA_ITEM_KEY */
+ if (slot == 0) {
+ btrfs_set_path_blocking(path);
+ ret = btrfs_prev_leaf(root, path);
+ if (ret < 0)
+ goto out;
+ if (ret == 0) {
+ slot = btrfs_header_nritems(leaf) - 1;
+ btrfs_item_key_to_cpu(leaf, &extent_item_key,
+ slot);
+ }
+ } else {
+ btrfs_item_key_to_cpu(leaf, &extent_item_key, slot - 1);
+ ret = 0;
+ }
+
+ if (ret == 0 &&
+ extent_item_key.objectid == cache->start) {
+ if (extent_item_key.type == BTRFS_METADATA_ITEM_KEY)
+ length = fs_info->nodesize;
+ else if (extent_item_key.type == BTRFS_EXTENT_ITEM_KEY)
+ length = extent_item_key.offset;
+ else {
+ ret = -EUCLEAN;
+ goto out;
+ }
+ }
+
+ *offset_ret = length;
+ } else if (found_key.type == BTRFS_EXTENT_ITEM_KEY ||
+ found_key.type == BTRFS_METADATA_ITEM_KEY) {
+
+ if (found_key.type == BTRFS_EXTENT_ITEM_KEY)
+ length = found_key.offset;
+ else
+ length = fs_info->nodesize;
+
+ if (!(found_key.objectid >= cache->start &&
+ found_key.objectid + length <=
+ cache->start + cache->length)) {
+ ret = -EUCLEAN;
+ goto out;
+ }
+ *offset_ret = found_key.objectid + length - cache->start;
+ } else {
+ ret = -EUCLEAN;
+ goto out;
+ }
+ ret = 0;
+
+out:
+ btrfs_free_path(path);
+ return ret;
+}
+
int btrfs_load_block_group_zone_info(struct btrfs_block_group *cache)
{
struct btrfs_fs_info *fs_info = cache->fs_info;
@@ -767,6 +865,7 @@ int btrfs_load_block_group_zone_info(struct btrfs_block_group *cache)
int i;
unsigned int nofs_flag;
u64 *alloc_offsets = NULL;
+ u64 emulated_offset = 0;
u32 num_sequential = 0, num_conventional = 0;
if (!btrfs_fs_incompat(fs_info, ZONED))
@@ -867,12 +966,12 @@ int btrfs_load_block_group_zone_info(struct btrfs_block_group *cache)
}
if (num_conventional > 0) {
- /*
- * Since conventional zones does not have write pointer, we
- * cannot determine alloc_offset from the pointer
- */
- ret = -EINVAL;
- goto out;
+ ret = emulate_write_pointer(cache, &emulated_offset);
+ if (ret || map->num_stripes == num_conventional) {
+ if (!ret)
+ cache->alloc_offset = emulated_offset;
+ goto out;
+ }
}
switch (map->type & BTRFS_BLOCK_GROUP_PROFILE_MASK) {
@@ -894,6 +993,14 @@ int btrfs_load_block_group_zone_info(struct btrfs_block_group *cache)
}
out:
+ /* an extent is allocated after the write pointer */
+ if (num_conventional && emulated_offset > cache->alloc_offset) {
+ btrfs_err(fs_info,
+ "got wrong write pointer in BG %llu: %llu > %llu",
+ logical, emulated_offset, cache->alloc_offset);
+ ret = -EIO;
+ }
+
kfree(alloc_offsets);
free_extent_map(em);
Conventional zones do not have a write pointer. So, we cannot use it to determine the allocation offset if a block group contains a conventional zone. Instead, we can consider the end of the last allocated extent int the block group as an allocation offset. Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com> --- fs/btrfs/zoned.c | 119 ++++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 113 insertions(+), 6 deletions(-)