On Mon, Sep 11, 2023 at 05:52:04AM -0700, Johannes Thumshirn wrote:
> +static int btrfs_insert_striped_mirrored_raid_extents(
> + struct btrfs_trans_handle *trans,
> + struct btrfs_ordered_extent *ordered,
> + u64 map_type)
> +{
> + struct btrfs_io_context *bioc;
> + struct btrfs_io_context *rbioc;
> + const int nstripes = list_count_nodes(&ordered->bioc_list);
> + const int index = btrfs_bg_flags_to_raid_index(map_type);
> + const int substripes = btrfs_raid_array[index].sub_stripes;
> + const int max_stripes = trans->fs_info->fs_devices->rw_devices / 2;
> + int left = nstripes;
> + int stripe = 0, j = 0;
> + int i = 0;
Please move the initialization right before the block that uses the
variables.
> + int ret = 0;
> + u64 stripe_end;
> + u64 prev_end;
> +
> + if (nstripes == 1)
> + return btrfs_insert_mirrored_raid_extents(trans, ordered, map_type);
> +
> + rbioc = kzalloc(struct_size(rbioc, stripes, nstripes * substripes),
> + GFP_KERNEL);
> + if (!rbioc)
> + return -ENOMEM;
> +
> + rbioc->map_type = map_type;
> + rbioc->logical = list_first_entry(&ordered->bioc_list, typeof(*rbioc),
> + ordered_entry)->logical;
> +
> + stripe_end = rbioc->logical;
> + prev_end = stripe_end;
Like here, initializing i
> + list_for_each_entry(bioc, &ordered->bioc_list, ordered_entry) {
> +
> + rbioc->size += bioc->size;
> + for (j = 0; j < substripes; j++) {
And if you don't use 'j' outside of the for cycle you can use the
delcarations inside the for (...).
> + stripe = i + j;
> + rbioc->stripes[stripe].dev = bioc->stripes[j].dev;
> + rbioc->stripes[stripe].physical = bioc->stripes[j].physical;
> + rbioc->stripes[stripe].length = bioc->size;
> + }
> +
> + stripe_end += rbioc->size;
> + if (i >= nstripes ||
> + (stripe_end - prev_end >= max_stripes * BTRFS_STRIPE_LEN)) {
> + ret = btrfs_insert_one_raid_extent(trans,
> + nstripes * substripes,
> + rbioc);
> + if (ret)
> + goto out;
> +
> + left -= nstripes;
> + i = 0;
> + rbioc->logical += rbioc->size;
> + rbioc->size = 0;
> + } else {
> + i += substripes;
> + prev_end = stripe_end;
> + }
> + }
> +
> + if (left) {
> + bioc = list_prev_entry(bioc, ordered_entry);
> + ret = btrfs_insert_one_raid_extent(trans, substripes, bioc);
> + }
> +
> +out:
> + kfree(rbioc);
> + return ret;
> +}
> +
> +static int btrfs_insert_striped_raid_extents(struct btrfs_trans_handle *trans,
> + struct btrfs_ordered_extent *ordered,
> + u64 map_type)
> +{
> + struct btrfs_io_context *bioc;
> + struct btrfs_io_context *rbioc;
> + const int nstripes = list_count_nodes(&ordered->bioc_list);
> + int i = 0;
> + int ret = 0;
> +
> + rbioc = kzalloc(struct_size(rbioc, stripes, nstripes), GFP_KERNEL);
You can't use GFP_KERNEL generally in any function that takes a
transaction handle parameter. Either GFP_NOFS or with the
memalloc_nofs_* protection.
> + if (!rbioc)
> + return -ENOMEM;
> + rbioc->map_type = map_type;
> + rbioc->logical = list_first_entry(&ordered->bioc_list, typeof(*rbioc),
> + ordered_entry)->logical;
> +
Maybe initializing 'i' here would be better so it's consistent with
other code.
> + list_for_each_entry(bioc, &ordered->bioc_list, ordered_entry) {
> + rbioc->size += bioc->size;
> + rbioc->stripes[i].dev = bioc->stripes[0].dev;
> + rbioc->stripes[i].physical = bioc->stripes[0].physical;
> + rbioc->stripes[i].length = bioc->size;
> +
> + if (i == nstripes - 1) {
> + ret = btrfs_insert_one_raid_extent(trans, nstripes, rbioc);
> + if (ret)
> + goto out;
> +
> + i = 0;
> + rbioc->logical += rbioc->size;
> + rbioc->size = 0;
> + } else {
> + i++;
> + }
> + }
> +
> + if (i && i < nstripes - 1)
> + ret = btrfs_insert_one_raid_extent(trans, i, rbioc);
> +
> +out:
> + kfree(rbioc);
> + return ret;
> +}
> +
> +int btrfs_insert_raid_extent(struct btrfs_trans_handle *trans,
> + struct btrfs_ordered_extent *ordered_extent)
> +{
> + struct btrfs_io_context *bioc;
> + u64 map_type;
> + int ret;
> +
> + if (!trans->fs_info->stripe_root)
> + return 0;
> +
> + map_type = list_first_entry(&ordered_extent->bioc_list, typeof(*bioc),
> + ordered_entry)->map_type;
> +
> + switch (map_type & BTRFS_BLOCK_GROUP_PROFILE_MASK) {
> + case BTRFS_BLOCK_GROUP_DUP:
> + case BTRFS_BLOCK_GROUP_RAID1:
> + case BTRFS_BLOCK_GROUP_RAID1C3:
> + case BTRFS_BLOCK_GROUP_RAID1C4:
> + ret = btrfs_insert_mirrored_raid_extents(trans, ordered_extent,
> + map_type);
> + break;
> + case BTRFS_BLOCK_GROUP_RAID0:
> + ret = btrfs_insert_striped_raid_extents(trans, ordered_extent,
> + map_type);
> + break;
> + case BTRFS_BLOCK_GROUP_RAID10:
> + ret = btrfs_insert_striped_mirrored_raid_extents(trans, ordered_extent, map_type);
> + break;
> + default:
> + ret = -EINVAL;
> + break;
> + }
> +
> + while (!list_empty(&ordered_extent->bioc_list)) {
> + bioc = list_first_entry(&ordered_extent->bioc_list,
> + typeof(*bioc), ordered_entry);
> + list_del(&bioc->ordered_entry);
> + btrfs_put_bioc(bioc);
> + }
> +
> + return ret;
> +}
> diff --git a/fs/btrfs/raid-stripe-tree.h b/fs/btrfs/raid-stripe-tree.h
> new file mode 100644
> index 000000000000..f36e4c2d46b0
> --- /dev/null
> +++ b/fs/btrfs/raid-stripe-tree.h
> @@ -0,0 +1,34 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Copyright (C) 2023 Western Digital Corporation or its affiliates.
> + */
> +
> +#ifndef BTRFS_RAID_STRIPE_TREE_H
> +#define BTRFS_RAID_STRIPE_TREE_H
> +
> +#include "disk-io.h"
> +
> +struct btrfs_io_context;
> +struct btrfs_io_stripe;
Please add more forward declarations, btrfs_trans_handle,
btrfs_ordered_extent or fs_info.
> +
> +int btrfs_insert_raid_extent(struct btrfs_trans_handle *trans,
> + struct btrfs_ordered_extent *ordered_extent);
> +
> +static inline bool btrfs_need_stripe_tree_update(struct btrfs_fs_info *fs_info,
> + u64 map_type)
> +{
> + u64 type = map_type & BTRFS_BLOCK_GROUP_TYPE_MASK;
> + u64 profile = map_type & BTRFS_BLOCK_GROUP_PROFILE_MASK;
> +
> + if (!btrfs_stripe_tree_root(fs_info))
> + return false;
> +
> + if (type != BTRFS_BLOCK_GROUP_DATA)
> + return false;
> +
> + if (profile & BTRFS_BLOCK_GROUP_RAID1_MASK)
> + return true;
> +
> + return false;
> +}
> +#endif