On Fri, Oct 30, 2020 at 10:51:21PM +0900, Naohiro Aota wrote:
> @@ -733,3 +739,150 @@ int btrfs_ensure_empty_zones(struct btrfs_device *device, u64 start, u64 size)
>
> return 0;
> }
> +
> +int btrfs_load_block_group_zone_info(struct btrfs_block_group *cache)
> +{
> + struct btrfs_fs_info *fs_info = cache->fs_info;
> + struct extent_map_tree *em_tree = &fs_info->mapping_tree;
> + struct extent_map *em;
> + struct map_lookup *map;
> + struct btrfs_device *device;
> + u64 logical = cache->start;
> + u64 length = cache->length;
> + u64 physical = 0;
> + int ret;
> + int i;
> + unsigned int nofs_flag;
> + u64 *alloc_offsets = NULL;
> + u32 num_sequential = 0, num_conventional = 0;
> +
> + if (!btrfs_is_zoned(fs_info))
> + return 0;
> +
> + /* Sanity check */
> + if (!IS_ALIGNED(length, fs_info->zone_size)) {
> + btrfs_err(fs_info, "unaligned block group at %llu + %llu",
"zoned: block group %llu len %llu unaligned to zone size %u"
> + logical, length);
> + return -EIO;
> + }
> +
> + /* Get the chunk mapping */
> + read_lock(&em_tree->lock);
> + em = lookup_extent_mapping(em_tree, logical, length);
> + read_unlock(&em_tree->lock);
> +
> + if (!em)
> + return -EINVAL;
> +
> + map = em->map_lookup;
> +
> + /*
> + * Get the zone type: if the group is mapped to a non-sequential zone,
> + * there is no need for the allocation offset (fit allocation is OK).
> + */
> + alloc_offsets = kcalloc(map->num_stripes, sizeof(*alloc_offsets),
> + GFP_NOFS);
> + if (!alloc_offsets) {
> + free_extent_map(em);
> + return -ENOMEM;
> + }
> +
> + for (i = 0; i < map->num_stripes; i++) {
> + bool is_sequential;
> + struct blk_zone zone;
> +
> + device = map->stripes[i].dev;
> + physical = map->stripes[i].physical;
> +
> + if (device->bdev == NULL) {
> + alloc_offsets[i] = WP_MISSING_DEV;
> + continue;
> + }
> +
> + is_sequential = btrfs_dev_is_sequential(device, physical);
> + if (is_sequential)
> + num_sequential++;
> + else
> + num_conventional++;
> +
> + if (!is_sequential) {
> + alloc_offsets[i] = WP_CONVENTIONAL;
> + continue;
> + }
> +
> + /*
> + * This zone will be used for allocation, so mark this
> + * zone non-empty.
> + */
> + btrfs_dev_clear_zone_empty(device, physical);
> +
> + /*
> + * The group is mapped to a sequential zone. Get the zone write
> + * pointer to determine the allocation offset within the zone.
> + */
> + WARN_ON(!IS_ALIGNED(physical, fs_info->zone_size));
> + nofs_flag = memalloc_nofs_save();
> + ret = btrfs_get_dev_zone(device, physical, &zone);
> + memalloc_nofs_restore(nofs_flag);
> + if (ret == -EIO || ret == -EOPNOTSUPP) {
> + ret = 0;
> + alloc_offsets[i] = WP_MISSING_DEV;
> + continue;
> + } else if (ret) {
> + goto out;
> + }
> +
> + switch (zone.cond) {
> + case BLK_ZONE_COND_OFFLINE:
> + case BLK_ZONE_COND_READONLY:
> + btrfs_err(fs_info, "Offline/readonly zone %llu",
"zoned: offline/readonly zone %llu on device %s (devid %llu)"
> + physical >> device->zone_info->zone_size_shift);
> + alloc_offsets[i] = WP_MISSING_DEV;
> + break;
> + case BLK_ZONE_COND_EMPTY:
> + alloc_offsets[i] = 0;
> + break;
> + case BLK_ZONE_COND_FULL:
> + alloc_offsets[i] = fs_info->zone_size;
> + break;
> + default:
> + /* Partially used zone */
> + alloc_offsets[i] =
> + ((zone.wp - zone.start) << SECTOR_SHIFT);
> + break;
> + }
> + }
> +
> + if (num_conventional > 0) {
> + /*
> + * Since conventional zones does not have write pointer, we
... zones do not ...
> + * cannot determine alloc_offset from the pointer
> + */
> + ret = -EINVAL;
> + goto out;
> + }
> +
> + switch (map->type & BTRFS_BLOCK_GROUP_PROFILE_MASK) {
> + case 0: /* single */
> + cache->alloc_offset = alloc_offsets[0];
> + break;
> + case BTRFS_BLOCK_GROUP_DUP:
> + case BTRFS_BLOCK_GROUP_RAID1:
> + case BTRFS_BLOCK_GROUP_RAID0:
> + case BTRFS_BLOCK_GROUP_RAID10:
> + case BTRFS_BLOCK_GROUP_RAID5:
> + case BTRFS_BLOCK_GROUP_RAID6:
> + /* non-SINGLE profiles are not supported yet */
> + default:
> + btrfs_err(fs_info, "Unsupported profile on ZONED %s",
"zoned: profile %s not supported"
> + btrfs_bg_type_to_raid_name(map->type));
> + ret = -EINVAL;
> + goto out;
> + }
> +
> +out:
> + kfree(alloc_offsets);
> + free_extent_map(em);
> +
> + return ret;
> +}
> diff --git a/fs/btrfs/zoned.h b/fs/btrfs/zoned.h
> index 24dd0c9561f9..90ed43a25595 100644
> --- a/fs/btrfs/zoned.h
> +++ b/fs/btrfs/zoned.h
> @@ -39,6 +39,7 @@ u64 btrfs_find_allocatable_zones(struct btrfs_device *device, u64 hole_start,
> int btrfs_reset_device_zone(struct btrfs_device *device, u64 physical,
> u64 length, u64 *bytes);
> int btrfs_ensure_empty_zones(struct btrfs_device *device, u64 start, u64 size);
> +int btrfs_load_block_group_zone_info(struct btrfs_block_group *cache);
> #else /* CONFIG_BLK_DEV_ZONED */
> static inline int btrfs_get_dev_zone(struct btrfs_device *device, u64 pos,
> struct blk_zone *zone)
> @@ -99,6 +100,11 @@ static inline int btrfs_ensure_empty_zones(struct btrfs_device *device,
> {
> return 0;
> }
newline
> +static inline int btrfs_load_block_group_zone_info(
> + struct btrfs_block_group *cache)
> +{
> + return 0;
> +}
newline
> #endif
>
> static inline bool btrfs_dev_is_sequential(struct btrfs_device *device, u64 pos)
> --
> 2.27.0
