On Mon, Sep 11, 2023 at 05:52:04AM -0700, Johannes Thumshirn wrote:
> Add support for inserting stripe extents into the raid stripe tree on
> completion of every write that needs an extra logical-to-physical
> translation when using RAID.
>
> Inserting the stripe extents happens after the data I/O has completed,
> this is done to a) support zone-append and b) rule out the possibility of
> a RAID-write-hole.
>
> Signed-off-by: Johannes Thumshirn <[email protected]>
> ---
> fs/btrfs/Makefile | 2 +-
> fs/btrfs/bio.c | 23 ++++
> fs/btrfs/extent-tree.c | 1 +
> fs/btrfs/inode.c | 8 +-
> fs/btrfs/ordered-data.c | 1 +
> fs/btrfs/ordered-data.h | 2 +
> fs/btrfs/raid-stripe-tree.c | 266 ++++++++++++++++++++++++++++++++++++++++++++
> fs/btrfs/raid-stripe-tree.h | 34 ++++++
> fs/btrfs/volumes.c | 4 +-
> fs/btrfs/volumes.h | 15 ++-
> 10 files changed, 347 insertions(+), 9 deletions(-)
>
> diff --git a/fs/btrfs/Makefile b/fs/btrfs/Makefile
> index c57d80729d4f..525af975f61c 100644
> --- a/fs/btrfs/Makefile
> +++ b/fs/btrfs/Makefile
> @@ -33,7 +33,7 @@ btrfs-y += super.o ctree.o extent-tree.o print-tree.o root-tree.o dir-item.o \
> uuid-tree.o props.o free-space-tree.o tree-checker.o space-info.o \
> block-rsv.o delalloc-space.o block-group.o discard.o reflink.o \
> subpage.o tree-mod-log.o extent-io-tree.o fs.o messages.o bio.o \
> - lru_cache.o
> + lru_cache.o raid-stripe-tree.o
>
> btrfs-$(CONFIG_BTRFS_FS_POSIX_ACL) += acl.o
> btrfs-$(CONFIG_BTRFS_FS_REF_VERIFY) += ref-verify.o
> diff --git a/fs/btrfs/bio.c b/fs/btrfs/bio.c
> index 31ff36990404..ddbe6f8d4ea2 100644
> --- a/fs/btrfs/bio.c
> +++ b/fs/btrfs/bio.c
> @@ -14,6 +14,7 @@
> #include "rcu-string.h"
> #include "zoned.h"
> #include "file-item.h"
> +#include "raid-stripe-tree.h"
>
> static struct bio_set btrfs_bioset;
> static struct bio_set btrfs_clone_bioset;
> @@ -415,6 +416,9 @@ static void btrfs_orig_write_end_io(struct bio *bio)
> else
> bio->bi_status = BLK_STS_OK;
>
> + if (bio_op(bio) == REQ_OP_ZONE_APPEND && !bio->bi_status)
> + stripe->physical = bio->bi_iter.bi_sector << SECTOR_SHIFT;
> +
> btrfs_orig_bbio_end_io(bbio);
> btrfs_put_bioc(bioc);
> }
> @@ -426,6 +430,8 @@ static void btrfs_clone_write_end_io(struct bio *bio)
> if (bio->bi_status) {
> atomic_inc(&stripe->bioc->error);
> btrfs_log_dev_io_error(bio, stripe->dev);
> + } else if (bio_op(bio) == REQ_OP_ZONE_APPEND) {
> + stripe->physical = bio->bi_iter.bi_sector << SECTOR_SHIFT;
> }
>
> /* Pass on control to the original bio this one was cloned from */
> @@ -487,6 +493,7 @@ static void btrfs_submit_mirrored_bio(struct btrfs_io_context *bioc, int dev_nr)
> bio->bi_private = &bioc->stripes[dev_nr];
> bio->bi_iter.bi_sector = bioc->stripes[dev_nr].physical >> SECTOR_SHIFT;
> bioc->stripes[dev_nr].bioc = bioc;
> + bioc->size = bio->bi_iter.bi_size;
> btrfs_submit_dev_bio(bioc->stripes[dev_nr].dev, bio);
> }
>
> @@ -496,6 +503,8 @@ static void __btrfs_submit_bio(struct bio *bio, struct btrfs_io_context *bioc,
> if (!bioc) {
> /* Single mirror read/write fast path. */
> btrfs_bio(bio)->mirror_num = mirror_num;
> + if (bio_op(bio) != REQ_OP_READ)
> + btrfs_bio(bio)->orig_physical = smap->physical;
> bio->bi_iter.bi_sector = smap->physical >> SECTOR_SHIFT;
> if (bio_op(bio) != REQ_OP_READ)
> btrfs_bio(bio)->orig_physical = smap->physical;
> @@ -688,6 +697,20 @@ static bool btrfs_submit_chunk(struct btrfs_bio *bbio, int mirror_num)
> bio->bi_opf |= REQ_OP_ZONE_APPEND;
> }
>
> + if (is_data_bbio(bbio) && bioc &&
> + btrfs_need_stripe_tree_update(bioc->fs_info,
> + bioc->map_type)) {
> + /*
> + * No locking for the list update, as we only add to
> + * the list in the I/O submission path, and list
> + * iteration only happens in the completion path,
> + * which can't happen until after the last submission.
> + */
> + btrfs_get_bioc(bioc);
> + list_add_tail(&bioc->ordered_entry,
> + &bbio->ordered->bioc_list);
> + }
> +
> /*
> * Csum items for reloc roots have already been cloned at this
> * point, so they are handled as part of the no-checksum case.
> diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
> index 6f6838226fe7..2e11a699ab77 100644
> --- a/fs/btrfs/extent-tree.c
> +++ b/fs/btrfs/extent-tree.c
> @@ -42,6 +42,7 @@
> #include "file-item.h"
> #include "orphan.h"
> #include "tree-checker.h"
> +#include "raid-stripe-tree.h"
>
> #undef SCRAMBLE_DELAYED_REFS
>
> diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
> index bafca05940d7..6f71630248da 100644
> --- a/fs/btrfs/inode.c
> +++ b/fs/btrfs/inode.c
> @@ -71,6 +71,7 @@
> #include "super.h"
> #include "orphan.h"
> #include "backref.h"
> +#include "raid-stripe-tree.h"
>
> struct btrfs_iget_args {
> u64 ino;
> @@ -3091,6 +3092,10 @@ int btrfs_finish_one_ordered(struct btrfs_ordered_extent *ordered_extent)
>
> trans->block_rsv = &inode->block_rsv;
>
> + ret = btrfs_insert_raid_extent(trans, ordered_extent);
> + if (ret)
> + goto out;
> +
> if (test_bit(BTRFS_ORDERED_COMPRESSED, &ordered_extent->flags))
> compress_type = ordered_extent->compress_type;
> if (test_bit(BTRFS_ORDERED_PREALLOC, &ordered_extent->flags)) {
> @@ -3224,7 +3229,8 @@ int btrfs_finish_one_ordered(struct btrfs_ordered_extent *ordered_extent)
> int btrfs_finish_ordered_io(struct btrfs_ordered_extent *ordered)
> {
> if (btrfs_is_zoned(btrfs_sb(ordered->inode->i_sb)) &&
> - !test_bit(BTRFS_ORDERED_IOERR, &ordered->flags))
> + !test_bit(BTRFS_ORDERED_IOERR, &ordered->flags) &&
> + list_empty(&ordered->bioc_list))
> btrfs_finish_ordered_zoned(ordered);
> return btrfs_finish_one_ordered(ordered);
> }
> diff --git a/fs/btrfs/ordered-data.c b/fs/btrfs/ordered-data.c
> index 345c449d588c..55c7d5543265 100644
> --- a/fs/btrfs/ordered-data.c
> +++ b/fs/btrfs/ordered-data.c
> @@ -191,6 +191,7 @@ static struct btrfs_ordered_extent *alloc_ordered_extent(
> INIT_LIST_HEAD(&entry->log_list);
> INIT_LIST_HEAD(&entry->root_extent_list);
> INIT_LIST_HEAD(&entry->work_list);
> + INIT_LIST_HEAD(&entry->bioc_list);
> init_completion(&entry->completion);
>
> /*
> diff --git a/fs/btrfs/ordered-data.h b/fs/btrfs/ordered-data.h
> index 173bd5c5df26..1c51ac57e5df 100644
> --- a/fs/btrfs/ordered-data.h
> +++ b/fs/btrfs/ordered-data.h
> @@ -151,6 +151,8 @@ struct btrfs_ordered_extent {
> struct completion completion;
> struct btrfs_work flush_work;
> struct list_head work_list;
> +
> + struct list_head bioc_list;
> };
>
> static inline void
> diff --git a/fs/btrfs/raid-stripe-tree.c b/fs/btrfs/raid-stripe-tree.c
> new file mode 100644
> index 000000000000..2415698a8fef
> --- /dev/null
> +++ b/fs/btrfs/raid-stripe-tree.c
> @@ -0,0 +1,266 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (C) 2023 Western Digital Corporation or its affiliates.
> + */
> +
> +#include <linux/btrfs_tree.h>
> +
> +#include "ctree.h"
> +#include "fs.h"
> +#include "accessors.h"
> +#include "transaction.h"
> +#include "disk-io.h"
> +#include "raid-stripe-tree.h"
> +#include "volumes.h"
> +#include "misc.h"
> +#include "print-tree.h"
> +
> +static u8 btrfs_bg_type_to_raid_encoding(u64 map_type)
> +{
> + switch (map_type & BTRFS_BLOCK_GROUP_PROFILE_MASK) {
> + case BTRFS_BLOCK_GROUP_DUP:
> + return BTRFS_STRIPE_DUP;
> + case BTRFS_BLOCK_GROUP_RAID0:
> + return BTRFS_STRIPE_RAID0;
> + case BTRFS_BLOCK_GROUP_RAID1:
> + return BTRFS_STRIPE_RAID1;
> + case BTRFS_BLOCK_GROUP_RAID1C3:
> + return BTRFS_STRIPE_RAID1C3;
> + case BTRFS_BLOCK_GROUP_RAID1C4:
> + return BTRFS_STRIPE_RAID1C4;
> + case BTRFS_BLOCK_GROUP_RAID5:
> + return BTRFS_STRIPE_RAID5;
> + case BTRFS_BLOCK_GROUP_RAID6:
> + return BTRFS_STRIPE_RAID6;
> + case BTRFS_BLOCK_GROUP_RAID10:
> + return BTRFS_STRIPE_RAID10;
> + default:
> + ASSERT(0);
> + }
> +}
> +
> +static int btrfs_insert_one_raid_extent(struct btrfs_trans_handle *trans,
> + int num_stripes,
> + struct btrfs_io_context *bioc)
> +{
> + struct btrfs_fs_info *fs_info = trans->fs_info;
> + struct btrfs_key stripe_key;
> + struct btrfs_root *stripe_root = btrfs_stripe_tree_root(fs_info);
> + u8 encoding = btrfs_bg_type_to_raid_encoding(bioc->map_type);
> + struct btrfs_stripe_extent *stripe_extent;
> + size_t item_size;
> + int ret;
> +
> + item_size = struct_size(stripe_extent, strides, num_stripes);
> +
> + stripe_extent = kzalloc(item_size, GFP_NOFS);
> + if (!stripe_extent) {
> + btrfs_abort_transaction(trans, -ENOMEM);
> + btrfs_end_transaction(trans);
> + return -ENOMEM;
> + }
> +
> + btrfs_set_stack_stripe_extent_encoding(stripe_extent, encoding);
> + for (int i = 0; i < num_stripes; i++) {
> + u64 devid = bioc->stripes[i].dev->devid;
> + u64 physical = bioc->stripes[i].physical;
> + u64 length = bioc->stripes[i].length;
> + struct btrfs_raid_stride *raid_stride =
> + &stripe_extent->strides[i];
> +
> + if (length == 0)
> + length = bioc->size;
> +
> + btrfs_set_stack_raid_stride_devid(raid_stride, devid);
> + btrfs_set_stack_raid_stride_physical(raid_stride, physical);
> + btrfs_set_stack_raid_stride_length(raid_stride, length);
> + }
> +
> + stripe_key.objectid = bioc->logical;
> + stripe_key.type = BTRFS_RAID_STRIPE_KEY;
> + stripe_key.offset = bioc->size;
> +
> + ret = btrfs_insert_item(trans, stripe_root, &stripe_key, stripe_extent,
> + item_size);
> + if (ret)
> + btrfs_abort_transaction(trans, ret);
> +
> + kfree(stripe_extent);
> +
> + return ret;
> +}
> +
> +static int btrfs_insert_mirrored_raid_extents(struct btrfs_trans_handle *trans,
> + struct btrfs_ordered_extent *ordered,
> + u64 map_type)
> +{
> + int num_stripes = btrfs_bg_type_to_factor(map_type);
> + struct btrfs_io_context *bioc;
> + int ret;
> +
> + list_for_each_entry(bioc, &ordered->bioc_list, ordered_entry) {
> + ret = btrfs_insert_one_raid_extent(trans, num_stripes, bioc);
> + if (ret)
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> +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;
This could use the table based mirroring factor, right? Though we have
only raid10 and not the other C3 and C4 it's better to avoid the
hard coded constants.