diff options
| -rw-r--r-- | fs/btrfs/ctree.c | 5 | ||||
| -rw-r--r-- | fs/btrfs/ctree.h | 2 | ||||
| -rw-r--r-- | fs/btrfs/sysfs.c | 22 |
3 files changed, 29 insertions, 0 deletions
diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c index bd6ea433ed65..c1561097e5a3 100644 --- a/fs/btrfs/ctree.c +++ b/fs/btrfs/ctree.c @@ -53,6 +53,11 @@ const char *btrfs_super_csum_name(u16 csum_type) return btrfs_csums[csum_type].name; } +size_t __const btrfs_get_num_csums(void) +{ + return ARRAY_SIZE(btrfs_csums); +} + struct btrfs_path *btrfs_alloc_path(void) { return kmem_cache_zalloc(btrfs_path_cachep, GFP_NOFS); diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index d5c9fbe32c0c..b17944995e09 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -2163,6 +2163,8 @@ BTRFS_SETGET_STACK_FUNCS(super_uuid_tree_generation, struct btrfs_super_block, int btrfs_super_csum_size(const struct btrfs_super_block *s); const char *btrfs_super_csum_name(u16 csum_type); +size_t __const btrfs_get_num_csums(void); + /* * The leaf data grows from end-to-front in the node. diff --git a/fs/btrfs/sysfs.c b/fs/btrfs/sysfs.c index f6d3c80f2e28..41eb6a313bf8 100644 --- a/fs/btrfs/sysfs.c +++ b/fs/btrfs/sysfs.c @@ -295,8 +295,30 @@ static ssize_t rmdir_subvol_show(struct kobject *kobj, } BTRFS_ATTR(static_feature, rmdir_subvol, rmdir_subvol_show); +static ssize_t supported_checksums_show(struct kobject *kobj, + struct kobj_attribute *a, char *buf) +{ + ssize_t ret = 0; + int i; + + for (i = 0; i < btrfs_get_num_csums(); i++) { + /* + * This "trick" only works as long as 'enum btrfs_csum_type' has + * no holes in it + */ + ret += snprintf(buf + ret, PAGE_SIZE - ret, "%s%s", + (i == 0 ? "" : " "), btrfs_super_csum_name(i)); + + } + + ret += snprintf(buf + ret, PAGE_SIZE - ret, "\n"); + return ret; +} +BTRFS_ATTR(static_feature, supported_checksums, supported_checksums_show); + static struct attribute *btrfs_supported_static_feature_attrs[] = { BTRFS_ATTR_PTR(static_feature, rmdir_subvol), + BTRFS_ATTR_PTR(static_feature, supported_checksums), NULL }; |