On Sun, Jul 16, 2023 at 11:52:45PM -0400, Sweet Tea Dorminy wrote:
> Each extent_map will end up with a pointer to its associated
> fscrypt_info if any, which should have the same lifetime as the
> extent_map. Add creation of fscrypt_infos for new extent_maps, and
> freeing as appropriate.
>
> Signed-off-by: Sweet Tea Dorminy <sweettea-kernel@xxxxxxxxxx>
> ---
> fs/btrfs/extent_map.c | 8 ++++++++
> fs/btrfs/extent_map.h | 3 +++
> fs/btrfs/inode.c | 8 ++++++++
> 3 files changed, 19 insertions(+)
>
> diff --git a/fs/btrfs/extent_map.c b/fs/btrfs/extent_map.c
> index 0cdb3e86f29b..4fa5f97559da 100644
> --- a/fs/btrfs/extent_map.c
> +++ b/fs/btrfs/extent_map.c
> @@ -65,6 +65,8 @@ void free_extent_map(struct extent_map *em)
> if (!em)
> return;
> if (refcount_dec_and_test(&em->refs)) {
> + if (em->fscrypt_info)
> + fscrypt_free_extent_info(&em->fscrypt_info);
> WARN_ON(extent_map_in_tree(em));
> WARN_ON(!list_empty(&em->list));
> if (test_bit(EXTENT_FLAG_FS_MAPPING, &em->flags))
> @@ -207,6 +209,12 @@ static int mergable_maps(struct extent_map *prev, struct extent_map *next)
> if (!list_empty(&prev->list) || !list_empty(&next->list))
> return 0;
>
> + /*
> + * Don't merge adjacent encrypted maps.
> + */
> + if (prev->fscrypt_info || next->fscrypt_info)
> + return 0;
> +
> ASSERT(next->block_start != EXTENT_MAP_DELALLOC &&
> prev->block_start != EXTENT_MAP_DELALLOC);
>
> diff --git a/fs/btrfs/extent_map.h b/fs/btrfs/extent_map.h
> index 35d27c756e08..3a1b66b1cedf 100644
> --- a/fs/btrfs/extent_map.h
> +++ b/fs/btrfs/extent_map.h
> @@ -27,6 +27,8 @@ enum {
> EXTENT_FLAG_FS_MAPPING,
> /* This em is merged from two or more physically adjacent ems */
> EXTENT_FLAG_MERGED,
> + /* This em has a fscrypt info */
> + EXTENT_FLAG_ENCRYPTED,
> };
>
> struct extent_map {
> @@ -50,6 +52,7 @@ struct extent_map {
> */
> u64 generation;
> unsigned long flags;
> + struct fscrypt_info *fscrypt_info;
> /* Used for chunk mappings, flag EXTENT_FLAG_FS_MAPPING must be set */
> struct map_lookup *map_lookup;
> refcount_t refs;
> diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
> index 40c2ec328730..b43fc253ecd1 100644
> --- a/fs/btrfs/inode.c
> +++ b/fs/btrfs/inode.c
> @@ -7460,6 +7460,14 @@ static struct extent_map *create_io_em(struct btrfs_inode *inode, u64 start,
> em->compress_type = compress_type;
> }
>
> + ret = fscrypt_prepare_new_extent(&inode->vfs_inode, &em->fscrypt_info);
> + if (ret < 0) {
> + free_extent_map(em);
> + return ERR_PTR(ret);
> + }
> + if (em->fscrypt_info)
> + set_bit(EXTENT_FLAG_ENCRYPTED, &em->flags);
We don't check this flag anywhere, you can drop it. Thanks,
Josef
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