Re: [PATCH v3] btrfs: tests: add selftests for RAID stripe-tree

[Filipe Manana]

On Wed, Oct 2, 2024 at 11:12 AM Johannes Thumshirn <jth@xxxxxxxxxx> wrote:
>
> From: Johannes Thumshirn <johannes.thumshirn@xxxxxxx>
>
> Add first stash of very basic self tests for the RAID stripe-tree.
>
> More test cases will follow exercising the tree.
>
> Signed-off-by: Johannes Thumshirn <johannes.thumshirn@xxxxxxx>
> ---
> Changes to v2:
> * Fix update test-case
> * Remove local btrfs_device variables (Filipe)
> * Add prints to see where a test-case failed (Filipe)
>
> Link to v2:
> https://lore.kernel.org/linux-btrfs/20241001065451.2378-1-jth@xxxxxxxxxx
>
> Changes to v1:
> * Fix build errors with CONFIG_BTRFS_FS_RUN_SANITY_TESTS=n
> * Document expectations from the test cases
>
> Link to v1:
> https://lore.kernel.org/linux-btrfs/20240930104054.12290-1-jth@xxxxxxxxxx
>
>  fs/btrfs/Makefile                       |   3 +-
>  fs/btrfs/raid-stripe-tree.c             |   5 +-
>  fs/btrfs/raid-stripe-tree.h             |   5 +
>  fs/btrfs/tests/btrfs-tests.c            |   3 +
>  fs/btrfs/tests/btrfs-tests.h            |   1 +
>  fs/btrfs/tests/raid-stripe-tree-tests.c | 315 ++++++++++++++++++++++++
>  fs/btrfs/volumes.c                      |   6 +-
>  fs/btrfs/volumes.h                      |   5 +
>  8 files changed, 337 insertions(+), 6 deletions(-)
>  create mode 100644 fs/btrfs/tests/raid-stripe-tree-tests.c
>
> diff --git a/fs/btrfs/Makefile b/fs/btrfs/Makefile
> index 87617f2968bc..3cfc440c636c 100644
> --- a/fs/btrfs/Makefile
> +++ b/fs/btrfs/Makefile
> @@ -43,4 +43,5 @@ btrfs-$(CONFIG_FS_VERITY) += verity.o
>  btrfs-$(CONFIG_BTRFS_FS_RUN_SANITY_TESTS) += tests/free-space-tests.o \
>         tests/extent-buffer-tests.o tests/btrfs-tests.o \
>         tests/extent-io-tests.o tests/inode-tests.o tests/qgroup-tests.o \
> -       tests/free-space-tree-tests.o tests/extent-map-tests.o
> +       tests/free-space-tree-tests.o tests/extent-map-tests.o \
> +       tests/raid-stripe-tree-tests.o
> diff --git a/fs/btrfs/raid-stripe-tree.c b/fs/btrfs/raid-stripe-tree.c
> index 4c859b550f6c..b7787a8e4af2 100644
> --- a/fs/btrfs/raid-stripe-tree.c
> +++ b/fs/btrfs/raid-stripe-tree.c
> @@ -108,8 +108,9 @@ static int update_raid_extent_item(struct btrfs_trans_handle *trans,
>         return ret;
>  }
>
> -static int btrfs_insert_one_raid_extent(struct btrfs_trans_handle *trans,
> -                                       struct btrfs_io_context *bioc)
> +EXPORT_FOR_TESTS
> +int btrfs_insert_one_raid_extent(struct btrfs_trans_handle *trans,
> +                                struct btrfs_io_context *bioc)
>  {
>         struct btrfs_fs_info *fs_info = trans->fs_info;
>         struct btrfs_key stripe_key;
> diff --git a/fs/btrfs/raid-stripe-tree.h b/fs/btrfs/raid-stripe-tree.h
> index 1ac1c21aac2f..541836421778 100644
> --- a/fs/btrfs/raid-stripe-tree.h
> +++ b/fs/btrfs/raid-stripe-tree.h
> @@ -28,6 +28,11 @@ int btrfs_get_raid_extent_offset(struct btrfs_fs_info *fs_info,
>  int btrfs_insert_raid_extent(struct btrfs_trans_handle *trans,
>                              struct btrfs_ordered_extent *ordered_extent);
>
> +#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
> +int btrfs_insert_one_raid_extent(struct btrfs_trans_handle *trans,
> +                                struct btrfs_io_context *bioc);
> +#endif
> +
>  static inline bool btrfs_need_stripe_tree_update(struct btrfs_fs_info *fs_info,
>                                                  u64 map_type)
>  {
> diff --git a/fs/btrfs/tests/btrfs-tests.c b/fs/btrfs/tests/btrfs-tests.c
> index ce50847e1e01..18e1ab4a0914 100644
> --- a/fs/btrfs/tests/btrfs-tests.c
> +++ b/fs/btrfs/tests/btrfs-tests.c
> @@ -291,6 +291,9 @@ int btrfs_run_sanity_tests(void)
>                         ret = btrfs_test_free_space_tree(sectorsize, nodesize);
>                         if (ret)
>                                 goto out;
> +                       ret = btrfs_test_raid_stripe_tree(sectorsize, nodesize);
> +                       if (ret)
> +                               goto out;
>                 }
>         }
>         ret = btrfs_test_extent_map();
> diff --git a/fs/btrfs/tests/btrfs-tests.h b/fs/btrfs/tests/btrfs-tests.h
> index dc2f2ab15fa5..61bcadaf2036 100644
> --- a/fs/btrfs/tests/btrfs-tests.h
> +++ b/fs/btrfs/tests/btrfs-tests.h
> @@ -37,6 +37,7 @@ int btrfs_test_extent_io(u32 sectorsize, u32 nodesize);
>  int btrfs_test_inodes(u32 sectorsize, u32 nodesize);
>  int btrfs_test_qgroups(u32 sectorsize, u32 nodesize);
>  int btrfs_test_free_space_tree(u32 sectorsize, u32 nodesize);
> +int btrfs_test_raid_stripe_tree(u32 sectorsize, u32 nodesize);
>  int btrfs_test_extent_map(void);
>  struct inode *btrfs_new_test_inode(void);
>  struct btrfs_fs_info *btrfs_alloc_dummy_fs_info(u32 nodesize, u32 sectorsize);
> diff --git a/fs/btrfs/tests/raid-stripe-tree-tests.c b/fs/btrfs/tests/raid-stripe-tree-tests.c
> new file mode 100644
> index 000000000000..94f3cd9d2661
> --- /dev/null
> +++ b/fs/btrfs/tests/raid-stripe-tree-tests.c
> @@ -0,0 +1,315 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (C) 2024 Western Digital Corporation or its affiliates.
> + */
> +
> +#include <linux/sizes.h>
> +#include "../fs.h"
> +#include "../disk-io.h"
> +#include "../transaction.h"
> +#include "../volumes.h"
> +#include "../raid-stripe-tree.h"
> +#include "btrfs-tests.h"
> +
> +#define RST_TEST_NUM_DEVICES   2
> +#define RST_TEST_RAID1_TYPE    (BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_RAID1)
> +
> +typedef int (*test_func_t)(struct btrfs_trans_handle *trans);
> +
> +static struct btrfs_device *btrfs_device_by_devid(struct btrfs_fs_devices *fs_devices,
> +                                                 u64 devid)
> +{
> +       struct btrfs_device *dev;
> +
> +       list_for_each_entry(dev, &fs_devices->devices, dev_list) {
> +               if (dev->devid == devid)
> +                       return dev;
> +       }
> +
> +       return NULL;
> +}
> +
> +/*
> + * Test a 64k RST write on a 2 disk RAID1 at a logical address of 1M and then
> + * overwrite the whole range giving it new physical address at an offset of 1G.
> + * The intent of this test is to exercise the 'update_raid_extent_item()'
> + * function called be btrfs_insert_one_raid_extent().
> + */
> +static int test_create_update_delete(struct btrfs_trans_handle *trans)
> +{
> +       struct btrfs_fs_info *fs_info = trans->fs_info;
> +       struct btrfs_io_context *bioc;
> +       struct btrfs_io_stripe io_stripe = { };
> +       u64 map_type = RST_TEST_RAID1_TYPE;
> +       u64 logical = SZ_1M;
> +       u64 len = SZ_64K;
> +       int ret;
> +
> +       bioc = alloc_btrfs_io_context(fs_info, logical, RST_TEST_NUM_DEVICES);
> +       if (!bioc) {
> +               test_err("failed to allocate a btrfs_io_context");
> +               ret = -ENOMEM;
> +               goto out;
> +       }
> +
> +       io_stripe.dev = btrfs_device_by_devid(fs_info->fs_devices, 0);
> +       bioc->map_type = map_type;
> +       bioc->size = len;
> +
> +       for (int i = 0; i < RST_TEST_NUM_DEVICES; i++) {
> +               struct btrfs_io_stripe *stripe = &bioc->stripes[i];
> +
> +               stripe->dev = btrfs_device_by_devid(fs_info->fs_devices, i);
> +               if (!stripe->dev) {
> +                       test_err("cannot find device with devid %d", i);
> +                       ret = -EINVAL;
> +                       goto out;
> +               }
> +
> +               stripe->physical = logical + i * SZ_1G;
> +       }
> +
> +       ret = btrfs_insert_one_raid_extent(trans, bioc);
> +       if (ret) {
> +               test_err("inserting RAID extent failed: %d", ret);
> +               goto out;
> +       }
> +
> +       io_stripe.dev = btrfs_device_by_devid(fs_info->fs_devices, 0);
> +       if (!io_stripe.dev) {
> +               ret = -EINVAL;
> +               goto out;
> +       }
> +
> +       ret = btrfs_get_raid_extent_offset(fs_info, logical, &len, map_type, 0,
> +                                          &io_stripe);
> +       if (ret) {
> +               test_err("lookup for RAID extent [%llu, %llu] failed", logical,
> +                        logical + len);
> +               goto out;
> +       }
> +
> +       if (io_stripe.physical != logical) {
> +               test_err("invalid physical address, expected %llu, got %llu",
> +                        logical, io_stripe.physical);
> +               ret = -EINVAL;
> +               goto out;
> +       }
> +
> +       if (len != SZ_64K) {
> +               test_err("invalid stripe length, expected %llu, got %llu",
> +                        (u64)SZ_64K, len);
> +               ret = -EINVAL;
> +               goto out;
> +       }
> +
> +       for (int i = 0; i < RST_TEST_NUM_DEVICES; i++) {
> +               struct btrfs_io_stripe *stripe = &bioc->stripes[i];
> +
> +               stripe->dev = btrfs_device_by_devid(fs_info->fs_devices, i);
> +               if (!stripe->dev) {
> +                       test_err("cannot find device with devid %d", i);
> +                       ret = -EINVAL;
> +                       goto out;
> +               }
> +
> +               stripe->physical = SZ_1G + logical + i * SZ_1G;
> +       }
> +
> +       ret = btrfs_insert_one_raid_extent(trans, bioc);
> +       if (ret) {
> +               test_err("updating RAID extent failed: %d", ret);
> +               goto out;
> +       }
> +
> +       ret = btrfs_get_raid_extent_offset(fs_info, logical, &len, map_type, 0,
> +                                          &io_stripe);
> +       if (ret) {
> +               test_err("lookup for RAID extent [%llu, %llu] failed", logical,
> +                        logical + len);
> +               goto out;
> +       }
> +
> +       if (io_stripe.physical != logical + SZ_1G) {
> +               test_err("invalid physical address, expected %llu, got %llu",
> +                        logical + SZ_1G, io_stripe.physical);
> +               ret = -EINVAL;
> +               goto out;
> +       }
> +
> +       if (len != SZ_64K) {
> +               test_err("invalid stripe length, expected %llu, got %llu",
> +                        (u64)SZ_64K, len);
> +               ret = -EINVAL;
> +               goto out;
> +       }
> +
> +       ret = btrfs_delete_raid_extent(trans, logical, len);
> +       if (ret)
> +               test_err("deleting RAID extent [%llu, %llu] failed", logical,
> +                        logical + len);
> +
> +out:
> +       btrfs_put_bioc(bioc);
> +       return ret;
> +}
> +
> +/*
> + * Test a simple 64k RST write on a 2 disk RAID1 at a logical address of 1M.
> + * The "physical" copy on device 0 is at 1M, on device 1 it is at 1G+1M.
> + */
> +static int test_simple_create_delete(struct btrfs_trans_handle *trans)
> +{
> +       struct btrfs_fs_info *fs_info = trans->fs_info;
> +       struct btrfs_io_context *bioc;
> +       struct btrfs_io_stripe io_stripe = { };
> +       u64 map_type = RST_TEST_RAID1_TYPE;
> +       u64 logical = SZ_1M;
> +       u64 len = SZ_64K;
> +       int ret;
> +
> +       bioc = alloc_btrfs_io_context(fs_info, logical, RST_TEST_NUM_DEVICES);
> +       if (!bioc) {
> +               test_err("failed to allocate a btrfs_io_context");
> +               ret = -ENOMEM;
> +               goto out;
> +       }
> +
> +       bioc->map_type = map_type;
> +       bioc->size = SZ_64K;
> +
> +       for (int i = 0; i < RST_TEST_NUM_DEVICES; i++) {
> +               struct btrfs_io_stripe *stripe = &bioc->stripes[i];
> +
> +               stripe->dev = btrfs_device_by_devid(fs_info->fs_devices, i);
> +               if (!stripe->dev) {
> +                       test_err("cannot find device with devid %d", i);
> +                       ret = -EINVAL;
> +                       goto out;
> +               }
> +
> +               stripe->physical = logical + i * SZ_1G;
> +       }
> +
> +       ret = btrfs_insert_one_raid_extent(trans, bioc);
> +       if (ret) {
> +               test_err("inserting RAID extent failed: %d", ret);
> +               goto out;
> +       }
> +
> +       io_stripe.dev = btrfs_device_by_devid(fs_info->fs_devices, 0);
> +       if (!io_stripe.dev) {
> +               ret = -EINVAL;
> +               goto out;
> +       }
> +
> +       ret = btrfs_get_raid_extent_offset(fs_info, logical, &len, map_type, 0,
> +                                          &io_stripe);
> +       if (ret)  {
> +               test_err("lookup for RAID extent [%llu, %llu] failed", logical,
> +                        logical + len);
> +               goto out;
> +       }
> +
> +       if (io_stripe.physical != logical) {
> +               test_err("invalid physical address, expected %llu, got %llu",
> +                        logical, io_stripe.physical);
> +               ret = -EINVAL;
> +               goto out;
> +       }
> +
> +       if (len != SZ_64K) {
> +               test_err("invalid stripe length, expected %llu, got %llu",
> +                        (u64)SZ_64K, len);
> +               ret = -EINVAL;
> +               goto out;
> +       }
> +
> +       ret = btrfs_delete_raid_extent(trans, logical, len);
> +       if (ret)
> +               test_err("deleting RAID extent [%llu, %llu] failed", logical,
> +                        logical + len);
> +
> +out:
> +       btrfs_put_bioc(bioc);
> +       return ret;
> +}
> +
> +test_func_t tests[] = {
> +       test_simple_create_delete,
> +       test_create_update_delete,
> +};
> +
> +static int run_test(test_func_t test, u32 sectorsize, u32 nodesize)
> +{
> +       struct btrfs_trans_handle trans;
> +       struct btrfs_fs_info *fs_info;
> +       struct btrfs_root *root = NULL;
> +       int ret;
> +
> +       fs_info = btrfs_alloc_dummy_fs_info(sectorsize, nodesize);
> +       if (!fs_info) {
> +               test_std_err(TEST_ALLOC_FS_INFO);
> +               ret = -ENOMEM;
> +               goto out;
> +       }
> +
> +       root = btrfs_alloc_dummy_root(fs_info);
> +       if (IS_ERR(root)) {
> +               test_std_err(TEST_ALLOC_ROOT);
> +               ret = PTR_ERR(root);
> +               goto out;
> +       }
> +       btrfs_set_super_compat_ro_flags(root->fs_info->super_copy,
> +               BTRFS_FEATURE_INCOMPAT_RAID_STRIPE_TREE);
> +       root->root_key.objectid = BTRFS_RAID_STRIPE_TREE_OBJECTID;
> +       root->root_key.type = BTRFS_ROOT_ITEM_KEY;
> +       root->root_key.offset = 0;
> +       fs_info->stripe_root = root;
> +       root->fs_info->tree_root = root;
> +
> +       root->node = alloc_test_extent_buffer(root->fs_info, nodesize);
> +       if (IS_ERR(root->node)) {
> +               test_std_err(TEST_ALLOC_EXTENT_BUFFER);
> +               ret = PTR_ERR(root->node);
> +               goto out;
> +       }
> +       btrfs_set_header_level(root->node, 0);
> +       btrfs_set_header_nritems(root->node, 0);
> +       root->alloc_bytenr += 2 * nodesize;
> +
> +       for (int i = 0; i < RST_TEST_NUM_DEVICES; i++) {
> +               struct btrfs_device *dev;
> +
> +               dev = btrfs_alloc_dummy_device(fs_info);

Still missing the error check, it can fail with ERR_PTR(-ENOMEM).

With that fixed:

Reviewed-by: Filipe Manana <fdmanana@xxxxxxxx>

Thanks.

> +               dev->devid = i;
> +       }
> +
> +       btrfs_init_dummy_trans(&trans, root->fs_info);
> +       ret = test(&trans);
> +       if (ret)
> +               goto out;
> +
> +out:
> +       btrfs_free_dummy_root(root);
> +       btrfs_free_dummy_fs_info(fs_info);
> +
> +       return ret;
> +}
> +
> +int btrfs_test_raid_stripe_tree(u32 sectorsize, u32 nodesize)
> +{
> +       int ret = 0;
> +
> +       test_msg("running RAID stripe-tree tests");
> +       for (int i = 0; i < ARRAY_SIZE(tests); i++) {
> +               ret = run_test(tests[i], sectorsize, nodesize);
> +               if (ret) {
> +                       test_err("test-case %ps failed with %d\n", tests[i], ret);
> +                       goto out;
> +               }
> +       }
> +
> +out:
> +       return ret;
> +}
> diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
> index 9a0fcebf34da..35c4d151b5b0 100644
> --- a/fs/btrfs/volumes.c
> +++ b/fs/btrfs/volumes.c
> @@ -6022,9 +6022,9 @@ static int find_live_mirror(struct btrfs_fs_info *fs_info,
>         return preferred_mirror;
>  }
>
> -static struct btrfs_io_context *alloc_btrfs_io_context(struct btrfs_fs_info *fs_info,
> -                                                      u64 logical,
> -                                                      u16 total_stripes)
> +EXPORT_FOR_TESTS
> +struct btrfs_io_context *alloc_btrfs_io_context(struct btrfs_fs_info *fs_info,
> +                                               u64 logical, u16 total_stripes)
>  {
>         struct btrfs_io_context *bioc;
>
> diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h
> index 26e35fc1c8fd..3ebb3c2732b0 100644
> --- a/fs/btrfs/volumes.h
> +++ b/fs/btrfs/volumes.h
> @@ -840,4 +840,9 @@ bool btrfs_repair_one_zone(struct btrfs_fs_info *fs_info, u64 logical);
>  bool btrfs_pinned_by_swapfile(struct btrfs_fs_info *fs_info, void *ptr);
>  const u8 *btrfs_sb_fsid_ptr(const struct btrfs_super_block *sb);
>
> +#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
> +struct btrfs_io_context *alloc_btrfs_io_context(struct btrfs_fs_info *fs_info,
> +                                               u64 logical, u16 total_stripes);
> +#endif
> +
>  #endif
> --
> 2.43.0
>
>