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| author |   Eric Biggers <ebiggers@google.com> | 2019-10-24 14:54:37 -0700 |
|---|---|---|
| committer | Eric Biggers <ebiggers@google.com> | 2019-11-06 12:34:42 -0800 |
| commit | b925acb8f83d7ce3582b34018c05aae1be666abf (patch) | |
| tree | a60000768b7455c72cdf7aebb623191506d11634 /fs/ext4 | |
| parent | fscrypt: add support for IV_INO_LBLK_64 policies (diff) | |
| download | linux-dev-b925acb8f83d7ce3582b34018c05aae1be666abf.tar.xz linux-dev-b925acb8f83d7ce3582b34018c05aae1be666abf.zip | |
ext4: add support for IV_INO_LBLK_64 encryption policies
IV_INO_LBLK_64 encryption policies have special requirements from the
filesystem beyond those of the existing encryption policies:
- Inode numbers must never change, even if the filesystem is resized.
- Inode numbers must be <= 32 bits.
- File logical block numbers must be <= 32 bits.
ext4 has 32-bit inode and file logical block numbers. However,
resize2fs can re-number inodes when shrinking an ext4 filesystem.
However, typically the people who would want to use this format don't
care about filesystem shrinking. They'd be fine with a solution that
just prevents the filesystem from being shrunk.
Therefore, add a new feature flag EXT4_FEATURE_COMPAT_STABLE_INODES that
will do exactly that. Then wire up the fscrypt_operations to expose
this flag to fs/crypto/, so that it allows IV_INO_LBLK_64 policies when
this flag is set.
Acked-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Diffstat (limited to 'fs/ext4')
| -rw-r--r-- | fs/ext4/ext4.h | 2 | ||||
| -rw-r--r-- | fs/ext4/super.c | 14 |
2 files changed, 16 insertions, 0 deletions
diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index 03db3e71676c..b3a2cc7c0252 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -1678,6 +1678,7 @@ static inline bool ext4_verity_in_progress(struct inode *inode) #define EXT4_FEATURE_COMPAT_RESIZE_INODE 0x0010 #define EXT4_FEATURE_COMPAT_DIR_INDEX 0x0020 #define EXT4_FEATURE_COMPAT_SPARSE_SUPER2 0x0200 +#define EXT4_FEATURE_COMPAT_STABLE_INODES 0x0800 #define EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER 0x0001 #define EXT4_FEATURE_RO_COMPAT_LARGE_FILE 0x0002 @@ -1779,6 +1780,7 @@ EXT4_FEATURE_COMPAT_FUNCS(xattr, EXT_ATTR) EXT4_FEATURE_COMPAT_FUNCS(resize_inode, RESIZE_INODE) EXT4_FEATURE_COMPAT_FUNCS(dir_index, DIR_INDEX) EXT4_FEATURE_COMPAT_FUNCS(sparse_super2, SPARSE_SUPER2) +EXT4_FEATURE_COMPAT_FUNCS(stable_inodes, STABLE_INODES) EXT4_FEATURE_RO_COMPAT_FUNCS(sparse_super, SPARSE_SUPER) EXT4_FEATURE_RO_COMPAT_FUNCS(large_file, LARGE_FILE) diff --git a/fs/ext4/super.c b/fs/ext4/super.c index dd654e53ba3d..b3cbf8622eab 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -1345,6 +1345,18 @@ static bool ext4_dummy_context(struct inode *inode) return DUMMY_ENCRYPTION_ENABLED(EXT4_SB(inode->i_sb)); } +static bool ext4_has_stable_inodes(struct super_block *sb) +{ + return ext4_has_feature_stable_inodes(sb); +} + +static void ext4_get_ino_and_lblk_bits(struct super_block *sb, + int *ino_bits_ret, int *lblk_bits_ret) +{ + *ino_bits_ret = 8 * sizeof(EXT4_SB(sb)->s_es->s_inodes_count); + *lblk_bits_ret = 8 * sizeof(ext4_lblk_t); +} + static const struct fscrypt_operations ext4_cryptops = { .key_prefix = "ext4:", .get_context = ext4_get_context, @@ -1352,6 +1364,8 @@ static const struct fscrypt_operations ext4_cryptops = { .dummy_context = ext4_dummy_context, .empty_dir = ext4_empty_dir, .max_namelen = EXT4_NAME_LEN, + .has_stable_inodes = ext4_has_stable_inodes, + .get_ino_and_lblk_bits = ext4_get_ino_and_lblk_bits, }; #endif |