[patch] Remove notion of key schemes
Joel Reardon
joel at clambassador.com
Thu Mar 15 10:48:56 EDT 2012
Removed the notion of different key schemes for ubifs with a single 64
bit key scheme. Reduced the size of UBIFS keys to 8 bytes
globally. Fill in the void left by the shorter key with a cryptolookup
field (8 byte) for data node and padding for the other nodes.
Changed zero_* functions to operate on the new padding. Replaced key scheme
enum with one entry into a define.
This was tested using integck and writing files on a nandsimmed partition
using both the vanilla version of ubifs and the modified version. Data
was written using both ubifs drivers and successfully read when later
mounting with either driver.
Signed-off-by: Joel Reardon <reardonj at inf.ethz.ch>
---
fs/ubifs/dir.c | 2 +-
fs/ubifs/journal.c | 2 +
fs/ubifs/key.h | 78 ++++++++++++++++++++---------------------------
fs/ubifs/sb.c | 4 +-
fs/ubifs/ubifs-media.h | 38 ++++++++++-------------
fs/ubifs/ubifs.h | 12 ++++----
6 files changed, 61 insertions(+), 75 deletions(-)
diff --git a/fs/ubifs/dir.c b/fs/ubifs/dir.c
index ec9f187..7e87f92 100644
--- a/fs/ubifs/dir.c
+++ b/fs/ubifs/dir.c
@@ -365,7 +365,7 @@ static int ubifs_readdir(struct file *file, void *dirent, filldir_t filldir)
dbg_gen("dir ino %lu, f_pos %#llx", dir->i_ino, file->f_pos);
- if (file->f_pos > UBIFS_S_KEY_HASH_MASK || file->f_pos == 2)
+ if (file->f_pos > UBIFS_KEY_HASH_MASK || file->f_pos == 2)
/*
* The directory was seek'ed to a senseless position or there
* are no more entries.
diff --git a/fs/ubifs/journal.c b/fs/ubifs/journal.c
index 2f438ab..d7b8f10 100644
--- a/fs/ubifs/journal.c
+++ b/fs/ubifs/journal.c
@@ -66,6 +66,7 @@
*/
static inline void zero_ino_node_unused(struct ubifs_ino_node *ino)
{
+ memset(ino->padding0, 0, 8);
memset(ino->padding1, 0, 4);
memset(ino->padding2, 0, 26);
}
@@ -77,6 +78,7 @@ static inline void zero_ino_node_unused(struct ubifs_ino_node *ino)
*/
static inline void zero_dent_node_unused(struct ubifs_dent_node *dent)
{
+ memset(dent->padding0, 0, 8);
dent->padding1 = 0;
memset(dent->padding2, 0, 4);
}
diff --git a/fs/ubifs/key.h b/fs/ubifs/key.h
index 92a8491..5dc1e2b 100644
--- a/fs/ubifs/key.h
+++ b/fs/ubifs/key.h
@@ -22,16 +22,13 @@
/*
* This header contains various key-related definitions and helper function.
- * UBIFS allows several key schemes, so we access key fields only via these
- * helpers. At the moment only one key scheme is supported.
+ * All access to key fields must be done only via the helper functions
+ * defined in this file.
*
- * Simple key scheme
- * ~~~~~~~~~~~~~~~~~
- *
- * Keys are 64-bits long. First 32-bits are inode number (parent inode number
- * in case of direntry key). Next 3 bits are node type. The last 29 bits are
- * 4KiB offset in case of inode node, and direntry hash in case of a direntry
- * node. We use "r5" hash borrowed from reiserfs.
+ * Keys are 64-bits long. The first 32-bits are inode number (parent inode
+ * number in case of direntry key). The next 3 bits are node type. The next
+ * 29 bits are 4KiB offset in case of inode node, and direntry hash in case
+ * of a direntry node. We use "r5" hash borrowed from reiserfs.
*/
#ifndef __UBIFS_KEY_H__
@@ -47,7 +44,7 @@
*/
static inline uint32_t key_mask_hash(uint32_t hash)
{
- hash &= UBIFS_S_KEY_HASH_MASK;
+ hash &= UBIFS_KEY_HASH_MASK;
if (unlikely(hash <= 2))
hash += 3;
return hash;
@@ -97,7 +94,7 @@ static inline void ino_key_init(const struct ubifs_info *c,
union ubifs_key *key, ino_t inum)
{
key->u32[0] = inum;
- key->u32[1] = UBIFS_INO_KEY << UBIFS_S_KEY_BLOCK_BITS;
+ key->u32[1] = UBIFS_INO_KEY << UBIFS_KEY_BLOCK_BITS;
}
/**
@@ -112,8 +109,7 @@ static inline void ino_key_init_flash(const struct ubifs_info *c, void *k,
union ubifs_key *key = k;
key->j32[0] = cpu_to_le32(inum);
- key->j32[1] = cpu_to_le32(UBIFS_INO_KEY << UBIFS_S_KEY_BLOCK_BITS);
- memset(k + 8, 0, UBIFS_MAX_KEY_LEN - 8);
+ key->j32[1] = cpu_to_le32(UBIFS_INO_KEY << UBIFS_KEY_BLOCK_BITS);
}
/**
@@ -155,9 +151,9 @@ static inline void dent_key_init(const struct ubifs_info *c,
{
uint32_t hash = c->key_hash(nm->name, nm->len);
- ubifs_assert(!(hash & ~UBIFS_S_KEY_HASH_MASK));
+ ubifs_assert(!(hash & ~UBIFS_KEY_HASH_MASK));
key->u32[0] = inum;
- key->u32[1] = hash | (UBIFS_DENT_KEY << UBIFS_S_KEY_HASH_BITS);
+ key->u32[1] = hash | (UBIFS_DENT_KEY << UBIFS_KEY_HASH_BITS);
}
/**
@@ -172,9 +168,9 @@ static inline void dent_key_init_hash(const struct ubifs_info *c,
union ubifs_key *key, ino_t inum,
uint32_t hash)
{
- ubifs_assert(!(hash & ~UBIFS_S_KEY_HASH_MASK));
+ ubifs_assert(!(hash & ~UBIFS_KEY_HASH_MASK));
key->u32[0] = inum;
- key->u32[1] = hash | (UBIFS_DENT_KEY << UBIFS_S_KEY_HASH_BITS);
+ key->u32[1] = hash | (UBIFS_DENT_KEY << UBIFS_KEY_HASH_BITS);
}
/**
@@ -190,11 +186,10 @@ static inline void dent_key_init_flash(const struct ubifs_info *c, void *k,
union ubifs_key *key = k;
uint32_t hash = c->key_hash(nm->name, nm->len);
- ubifs_assert(!(hash & ~UBIFS_S_KEY_HASH_MASK));
+ ubifs_assert(!(hash & ~UBIFS_KEY_HASH_MASK));
key->j32[0] = cpu_to_le32(inum);
key->j32[1] = cpu_to_le32(hash |
- (UBIFS_DENT_KEY << UBIFS_S_KEY_HASH_BITS));
- memset(k + 8, 0, UBIFS_MAX_KEY_LEN - 8);
+ (UBIFS_DENT_KEY << UBIFS_KEY_HASH_BITS));
}
/**
@@ -207,7 +202,7 @@ static inline void lowest_dent_key(const struct ubifs_info *c,
union ubifs_key *key, ino_t inum)
{
key->u32[0] = inum;
- key->u32[1] = UBIFS_DENT_KEY << UBIFS_S_KEY_HASH_BITS;
+ key->u32[1] = UBIFS_DENT_KEY << UBIFS_KEY_HASH_BITS;
}
/**
@@ -223,9 +218,9 @@ static inline void xent_key_init(const struct ubifs_info *c,
{
uint32_t hash = c->key_hash(nm->name, nm->len);
- ubifs_assert(!(hash & ~UBIFS_S_KEY_HASH_MASK));
+ ubifs_assert(!(hash & ~UBIFS_KEY_HASH_MASK));
key->u32[0] = inum;
- key->u32[1] = hash | (UBIFS_XENT_KEY << UBIFS_S_KEY_HASH_BITS);
+ key->u32[1] = hash | (UBIFS_XENT_KEY << UBIFS_KEY_HASH_BITS);
}
/**
@@ -241,11 +236,10 @@ static inline void xent_key_init_flash(const struct ubifs_info *c, void *k,
union ubifs_key *key = k;
uint32_t hash = c->key_hash(nm->name, nm->len);
- ubifs_assert(!(hash & ~UBIFS_S_KEY_HASH_MASK));
+ ubifs_assert(!(hash & ~UBIFS_KEY_HASH_MASK));
key->j32[0] = cpu_to_le32(inum);
key->j32[1] = cpu_to_le32(hash |
- (UBIFS_XENT_KEY << UBIFS_S_KEY_HASH_BITS));
- memset(k + 8, 0, UBIFS_MAX_KEY_LEN - 8);
+ (UBIFS_XENT_KEY << UBIFS_KEY_HASH_BITS));
}
/**
@@ -258,7 +252,7 @@ static inline void lowest_xent_key(const struct ubifs_info *c,
union ubifs_key *key, ino_t inum)
{
key->u32[0] = inum;
- key->u32[1] = UBIFS_XENT_KEY << UBIFS_S_KEY_HASH_BITS;
+ key->u32[1] = UBIFS_XENT_KEY << UBIFS_KEY_HASH_BITS;
}
/**
@@ -272,9 +266,9 @@ static inline void data_key_init(const struct ubifs_info *c,
union ubifs_key *key, ino_t inum,
unsigned int block)
{
- ubifs_assert(!(block & ~UBIFS_S_KEY_BLOCK_MASK));
+ ubifs_assert(!(block & ~UBIFS_KEY_BLOCK_MASK));
key->u32[0] = inum;
- key->u32[1] = block | (UBIFS_DATA_KEY << UBIFS_S_KEY_BLOCK_BITS);
+ key->u32[1] = block | (UBIFS_DATA_KEY << UBIFS_KEY_BLOCK_BITS);
}
/**
@@ -286,7 +280,7 @@ static inline void data_key_init(const struct ubifs_info *c,
static inline void highest_data_key(const struct ubifs_info *c,
union ubifs_key *key, ino_t inum)
{
- data_key_init(c, key, inum, UBIFS_S_KEY_BLOCK_MASK);
+ data_key_init(c, key, inum, UBIFS_KEY_BLOCK_MASK);
}
/**
@@ -302,7 +296,7 @@ static inline void trun_key_init(const struct ubifs_info *c,
union ubifs_key *key, ino_t inum)
{
key->u32[0] = inum;
- key->u32[1] = UBIFS_TRUN_KEY << UBIFS_S_KEY_BLOCK_BITS;
+ key->u32[1] = UBIFS_TRUN_KEY << UBIFS_KEY_BLOCK_BITS;
}
/**
@@ -327,7 +321,7 @@ static inline void invalid_key_init(const struct ubifs_info *c,
static inline int key_type(const struct ubifs_info *c,
const union ubifs_key *key)
{
- return key->u32[1] >> UBIFS_S_KEY_BLOCK_BITS;
+ return key->u32[1] >> UBIFS_KEY_BLOCK_BITS;
}
/**
@@ -339,7 +333,7 @@ static inline int key_type_flash(const struct ubifs_info *c, const void *k)
{
const union ubifs_key *key = k;
- return le32_to_cpu(key->j32[1]) >> UBIFS_S_KEY_BLOCK_BITS;
+ return le32_to_cpu(key->j32[1]) >> UBIFS_KEY_BLOCK_BITS;
}
/**
@@ -374,7 +368,7 @@ static inline ino_t key_inum_flash(const struct ubifs_info *c, const void *k)
static inline uint32_t key_hash(const struct ubifs_info *c,
const union ubifs_key *key)
{
- return key->u32[1] & UBIFS_S_KEY_HASH_MASK;
+ return key->u32[1] & UBIFS_KEY_HASH_MASK;
}
/**
@@ -386,7 +380,7 @@ static inline uint32_t key_hash_flash(const struct ubifs_info *c, const void *k)
{
const union ubifs_key *key = k;
- return le32_to_cpu(key->j32[1]) & UBIFS_S_KEY_HASH_MASK;
+ return le32_to_cpu(key->j32[1]) & UBIFS_KEY_HASH_MASK;
}
/**
@@ -397,7 +391,7 @@ static inline uint32_t key_hash_flash(const struct ubifs_info *c, const void *k)
static inline unsigned int key_block(const struct ubifs_info *c,
const union ubifs_key *key)
{
- return key->u32[1] & UBIFS_S_KEY_BLOCK_MASK;
+ return key->u32[1] & UBIFS_KEY_BLOCK_MASK;
}
/**
@@ -410,7 +404,7 @@ static inline unsigned int key_block_flash(const struct ubifs_info *c,
{
const union ubifs_key *key = k;
- return le32_to_cpu(key->j32[1]) & UBIFS_S_KEY_BLOCK_MASK;
+ return le32_to_cpu(key->j32[1]) & UBIFS_KEY_BLOCK_MASK;
}
/**
@@ -441,7 +435,6 @@ static inline void key_write(const struct ubifs_info *c,
t->j32[0] = cpu_to_le32(from->u32[0]);
t->j32[1] = cpu_to_le32(from->u32[1]);
- memset(to + 8, 0, UBIFS_MAX_KEY_LEN - 8);
}
/**
@@ -532,17 +525,12 @@ static inline int is_hash_key(const struct ubifs_info *c,
}
/**
- * key_max_inode_size - get maximum file size allowed by current key format.
+ * key_max_inode_size - get maximum file size allowed.
* @c: UBIFS file-system description object
*/
static inline unsigned long long key_max_inode_size(const struct ubifs_info *c)
{
- switch (c->key_fmt) {
- case UBIFS_SIMPLE_KEY_FMT:
- return (1ULL << UBIFS_S_KEY_BLOCK_BITS) * UBIFS_BLOCK_SIZE;
- default:
- return 0;
- }
+ return (1ULL << UBIFS_KEY_BLOCK_BITS) * UBIFS_BLOCK_SIZE;
}
#endif /* !__UBIFS_KEY_H__ */
diff --git a/fs/ubifs/sb.c b/fs/ubifs/sb.c
index 771f7fb..3fc9071 100644
--- a/fs/ubifs/sb.c
+++ b/fs/ubifs/sb.c
@@ -86,7 +86,7 @@ static int create_default_filesystem(struct ubifs_info *c)
__le64 tmp_le64;
/* Some functions called from here depend on the @c->key_len filed */
- c->key_len = UBIFS_SK_LEN;
+ c->key_len = UBIFS_KEY_LEN;
/*
* First of all, we have to calculate default file-system geometry -
@@ -599,7 +599,7 @@ int ubifs_read_superblock(struct ubifs_info *c)
switch (c->key_fmt) {
case UBIFS_SIMPLE_KEY_FMT:
- c->key_len = UBIFS_SK_LEN;
+ c->key_len = UBIFS_KEY_LEN;
break;
default:
ubifs_err("unsupported key format");
diff --git a/fs/ubifs/ubifs-media.h b/fs/ubifs/ubifs-media.h
index e24380c..0b769da 100644
--- a/fs/ubifs/ubifs-media.h
+++ b/fs/ubifs/ubifs-media.h
@@ -108,11 +108,11 @@
/* UBIFS padding byte pattern (must not be first or last byte of node magic) */
#define UBIFS_PADDING_BYTE 0xCE
-/* Maximum possible key length */
-#define UBIFS_MAX_KEY_LEN 16
+/* UBIFS key length */
+#define UBIFS_KEY_LEN 8
-/* Key length ("simple" format) */
-#define UBIFS_SK_LEN 8
+/* UBIFS key format */
+#define UBIFS_SIMPLE_KEY_FMT 0
/* Minimum index tree fanout */
#define UBIFS_MIN_FANOUT 3
@@ -196,22 +196,13 @@ enum {
};
/*
- * Supported key formats.
- *
- * UBIFS_SIMPLE_KEY_FMT: simple key format
- */
-enum {
- UBIFS_SIMPLE_KEY_FMT,
-};
-
-/*
* The simple key format uses 29 bits for storing UBIFS block number and hash
* value.
*/
-#define UBIFS_S_KEY_BLOCK_BITS 29
-#define UBIFS_S_KEY_BLOCK_MASK 0x1FFFFFFF
-#define UBIFS_S_KEY_HASH_BITS UBIFS_S_KEY_BLOCK_BITS
-#define UBIFS_S_KEY_HASH_MASK UBIFS_S_KEY_BLOCK_MASK
+#define UBIFS_KEY_BLOCK_BITS 29
+#define UBIFS_KEY_BLOCK_MASK 0x1FFFFFFF
+#define UBIFS_KEY_HASH_BITS UBIFS_KEY_BLOCK_BITS
+#define UBIFS_KEY_HASH_MASK UBIFS_KEY_BLOCK_MASK
/*
* Key types.
@@ -456,6 +447,7 @@ union ubifs_dev_desc {
* struct ubifs_ino_node - inode node.
* @ch: common header
* @key: node key
+ * @padding0: reserved for future, zeroes
* @creat_sqnum: sequence number at time of creation
* @size: inode size in bytes (amount of uncompressed data)
* @atime_sec: access time seconds
@@ -489,7 +481,8 @@ union ubifs_dev_desc {
*/
struct ubifs_ino_node {
struct ubifs_ch ch;
- __u8 key[UBIFS_MAX_KEY_LEN];
+ __u8 key[UBIFS_KEY_LEN];
+ __u8 padding0[8]; /* Watch 'zero_ino_node_unused()' if changing! */
__le64 creat_sqnum;
__le64 size;
__le64 atime_sec;
@@ -517,6 +510,7 @@ struct ubifs_ino_node {
* struct ubifs_dent_node - directory entry node.
* @ch: common header
* @key: node key
+ * @padding0: reserved for future, zeroes
* @inum: target inode number
* @padding1: reserved for future, zeroes
* @type: type of the target inode (%UBIFS_ITYPE_REG, %UBIFS_ITYPE_DIR, etc)
@@ -529,9 +523,10 @@ struct ubifs_ino_node {
*/
struct ubifs_dent_node {
struct ubifs_ch ch;
- __u8 key[UBIFS_MAX_KEY_LEN];
+ __u8 key[UBIFS_KEY_LEN];
+ __u8 padding0[8]; /* Watch 'zero_dent_node_unused()' if changing! */
__le64 inum;
- __u8 padding1;
+ __u8 padding1; /* Watch 'zero_dent_node_unused()' if changing! */
__u8 type;
__le16 nlen;
__u8 padding2[4]; /* Watch 'zero_dent_node_unused()' if changing! */
@@ -552,7 +547,8 @@ struct ubifs_dent_node {
*/
struct ubifs_data_node {
struct ubifs_ch ch;
- __u8 key[UBIFS_MAX_KEY_LEN];
+ __u8 key[UBIFS_KEY_LEN];
+ __le64 crypto_lookup;
__le32 size;
__le16 compr_type;
__u8 padding[2]; /* Watch 'zero_data_node_unused()' if changing! */
diff --git a/fs/ubifs/ubifs.h b/fs/ubifs/ubifs.h
index 93d59ac..7c343e1 100644
--- a/fs/ubifs/ubifs.h
+++ b/fs/ubifs/ubifs.h
@@ -274,10 +274,10 @@ struct ubifs_old_idx {
/* The below union makes it easier to deal with keys */
union ubifs_key {
- uint8_t u8[UBIFS_SK_LEN];
- uint32_t u32[UBIFS_SK_LEN/4];
- uint64_t u64[UBIFS_SK_LEN/8];
- __le32 j32[UBIFS_SK_LEN/4];
+ uint8_t u8[UBIFS_KEY_LEN];
+ uint32_t u32[UBIFS_KEY_LEN/4];
+ uint64_t u64[UBIFS_KEY_LEN/8];
+ __le32 j32[UBIFS_KEY_LEN/4];
};
/**
@@ -1065,8 +1065,8 @@ struct ubifs_debug_info;
*
* @key_hash_type: type of the key hash
* @key_hash: direntry key hash function
- * @key_fmt: key format
- * @key_len: key length
+ * @key_fmt: (obsolete, set to 0) key format
+ * @key_len: key length in bytes
* @fanout: fanout of the index tree (number of links per indexing node)
*
* @min_io_size: minimal input/output unit size
--
1.7.0.4
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