1 files changed, 119 insertions, 15 deletions

diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index 0e01e90add8..cfc4e01b3c8 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -29,6 +29,7 @@
 #include <linux/wait.h>
 #include <linux/blockgroup_lock.h>
 #include <linux/percpu_counter.h>
+#include <crypto/hash.h>
 #ifdef __KERNEL__
 #include <linux/compat.h>
 #endif
@@ -298,7 +299,9 @@ struct ext4_group_desc
         __le16  bg_free_inodes_count_lo;/* Free inodes count */
         __le16  bg_used_dirs_count_lo;  /* Directories count */
         __le16  bg_flags;               /* EXT4_BG_flags (INODE_UNINIT, etc) */
-        __u32   bg_reserved[2];         /* Likely block/inode bitmap checksum */
+        __le32  bg_exclude_bitmap_lo;   /* Exclude bitmap for snapshots */
+        __le16  bg_block_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+bbitmap) LE */
+        __le16  bg_inode_bitmap_csum_lo;/* crc32c(s_uuid+grp_num+ibitmap) LE */
         __le16  bg_itable_unused_lo;    /* Unused inodes count */
         __le16  bg_checksum;            /* crc16(sb_uuid+group+desc) */
         __le32  bg_block_bitmap_hi;     /* Blocks bitmap block MSB */
@@ -308,9 +311,19 @@ struct ext4_group_desc
         __le16  bg_free_inodes_count_hi;/* Free inodes count MSB */
         __le16  bg_used_dirs_count_hi;  /* Directories count MSB */
         __le16  bg_itable_unused_hi;    /* Unused inodes count MSB */
-        __u32   bg_reserved2[3];
+        __le32  bg_exclude_bitmap_hi;   /* Exclude bitmap block MSB */
+        __le16  bg_block_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+bbitmap) BE */
+        __le16  bg_inode_bitmap_csum_hi;/* crc32c(s_uuid+grp_num+ibitmap) BE */
+        __u32   bg_reserved;
 };
 
+#define EXT4_BG_INODE_BITMAP_CSUM_HI_END        \
+        (offsetof(struct ext4_group_desc, bg_inode_bitmap_csum_hi) + \
+         sizeof(__le16))
+#define EXT4_BG_BLOCK_BITMAP_CSUM_HI_END        \
+        (offsetof(struct ext4_group_desc, bg_block_bitmap_csum_hi) + \
+         sizeof(__le16))
+
 /*
  * Structure of a flex block group info
  */
@@ -650,7 +663,8 @@ struct ext4_inode {
                         __le16  l_i_file_acl_high;
                         __le16  l_i_uid_high;   /* these 2 fields */
                         __le16  l_i_gid_high;   /* were reserved2[0] */
-                        __u32   l_i_reserved2;
+                        __le16  l_i_checksum_lo;/* crc32c(uuid+inum+inode) LE */
+                        __le16  l_i_reserved;
                 } linux2;
                 struct {
                         __le16  h_i_reserved1;  /* Obsoleted fragment number/size which are removed in ext4 */
@@ -666,7 +680,7 @@ struct ext4_inode {
                 } masix2;
         } osd2;                         /* OS dependent 2 */
         __le16  i_extra_isize;
-        __le16  i_pad1;
+        __le16  i_checksum_hi;  /* crc32c(uuid+inum+inode) BE */
         __le32  i_ctime_extra;  /* extra Change time      (nsec << 2 | epoch) */
         __le32  i_mtime_extra;  /* extra Modification time(nsec << 2 | epoch) */
         __le32  i_atime_extra;  /* extra Access time      (nsec << 2 | epoch) */
@@ -768,7 +782,7 @@ do {									       \
 #define i_gid_low       i_gid
 #define i_uid_high      osd2.linux2.l_i_uid_high
 #define i_gid_high      osd2.linux2.l_i_gid_high
-#define i_reserved2     osd2.linux2.l_i_reserved2
+#define i_checksum_lo   osd2.linux2.l_i_checksum_lo
 
 #elif defined(__GNU__)
 
@@ -908,6 +922,9 @@ struct ext4_inode_info {
          */
         tid_t i_sync_tid;
         tid_t i_datasync_tid;
+
+        /* Precomputed uuid+inum+igen checksum for seeding inode checksums */
+        __u32 i_csum_seed;
 };
 
 /*
@@ -1001,6 +1018,9 @@ extern void ext4_set_bits(void *bm, int cur, int len);
 #define EXT4_ERRORS_PANIC               3       /* Panic */
 #define EXT4_ERRORS_DEFAULT             EXT4_ERRORS_CONTINUE
 
+/* Metadata checksum algorithm codes */
+#define EXT4_CRC32C_CHKSUM              1
+
 /*
  * Structure of the super block
  */
@@ -1087,7 +1107,7 @@ struct ext4_super_block {
         __le64  s_mmp_block;            /* Block for multi-mount protection */
         __le32  s_raid_stripe_width;    /* blocks on all data disks (N*stride)*/
         __u8    s_log_groups_per_flex;  /* FLEX_BG group size */
-        __u8    s_reserved_char_pad;
+        __u8    s_checksum_type;        /* metadata checksum algorithm used */
         __le16  s_reserved_pad;
         __le64  s_kbytes_written;       /* nr of lifetime kilobytes written */
         __le32  s_snapshot_inum;        /* Inode number of active snapshot */
@@ -1113,7 +1133,8 @@ struct ext4_super_block {
         __le32  s_usr_quota_inum;       /* inode for tracking user quota */
         __le32  s_grp_quota_inum;       /* inode for tracking group quota */
         __le32  s_overhead_clusters;    /* overhead blocks/clusters in fs */
-        __le32  s_reserved[109];        /* Padding to the end of the block */
+        __le32  s_reserved[108];        /* Padding to the end of the block */
+        __le32  s_checksum;             /* crc32c(superblock) */
 };
 
 #define EXT4_S_ERR_LEN (EXT4_S_ERR_END - EXT4_S_ERR_START)
@@ -1153,8 +1174,8 @@ struct ext4_sb_info {
         unsigned int s_mount_flags;
         unsigned int s_def_mount_opt;
         ext4_fsblk_t s_sb_block;
-        uid_t s_resuid;
-        gid_t s_resgid;
+        kuid_t s_resuid;
+        kgid_t s_resgid;
         unsigned short s_mount_state;
         unsigned short s_pad;
         int s_addr_per_block_bits;
@@ -1176,6 +1197,7 @@ struct ext4_sb_info {
         struct proc_dir_entry *s_proc;
         struct kobject s_kobj;
         struct completion s_kobj_unregister;
+        struct super_block *s_sb;
 
         /* Journaling */
         struct journal_s *s_journal;
@@ -1266,6 +1288,12 @@ struct ext4_sb_info {
 
         /* record the last minlen when FITRIM is called. */
         atomic_t s_last_trim_minblks;
+
+        /* Reference to checksum algorithm driver via cryptoapi */
+        struct crypto_shash *s_chksum_driver;
+
+        /* Precomputed FS UUID checksum for seeding other checksums */
+        __u32 s_csum_seed;
 };
 
 static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb)
@@ -1414,6 +1442,12 @@ static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
 #define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE      0x0040
 #define EXT4_FEATURE_RO_COMPAT_QUOTA            0x0100
 #define EXT4_FEATURE_RO_COMPAT_BIGALLOC         0x0200
+/*
+ * METADATA_CSUM also enables group descriptor checksums (GDT_CSUM).  When
+ * METADATA_CSUM is set, group descriptor checksums use the same algorithm as
+ * all other data structures' checksums.  However, the METADATA_CSUM and
+ * GDT_CSUM bits are mutually exclusive.
+ */
 #define EXT4_FEATURE_RO_COMPAT_METADATA_CSUM    0x0400
 
 #define EXT4_FEATURE_INCOMPAT_COMPRESSION       0x0001
@@ -1461,7 +1495,8 @@ static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
                                          EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE | \
                                          EXT4_FEATURE_RO_COMPAT_BTREE_DIR |\
                                          EXT4_FEATURE_RO_COMPAT_HUGE_FILE |\
-                                         EXT4_FEATURE_RO_COMPAT_BIGALLOC)
+                                         EXT4_FEATURE_RO_COMPAT_BIGALLOC |\
+                                         EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)
 
 /*
  * Default values for user and/or group using reserved blocks
@@ -1527,6 +1562,18 @@ struct ext4_dir_entry_2 {
 };
 
 /*
+ * This is a bogus directory entry at the end of each leaf block that
+ * records checksums.
+ */
+struct ext4_dir_entry_tail {
+        __le32  det_reserved_zero1;     /* Pretend to be unused */
+        __le16  det_rec_len;            /* 12 */
+        __u8    det_reserved_zero2;     /* Zero name length */
+        __u8    det_reserved_ft;        /* 0xDE, fake file type */
+        __le32  det_checksum;           /* crc32c(uuid+inum+dirblock) */
+};
+
+/*
  * Ext4 directory file types.  Only the low 3 bits are used.  The
  * other bits are reserved for now.
  */
@@ -1541,6 +1588,8 @@ struct ext4_dir_entry_2 {
 
 #define EXT4_FT_MAX             8
 
+#define EXT4_FT_DIR_CSUM        0xDE
+
 /*
  * EXT4_DIR_PAD defines the directory entries boundaries
  *
@@ -1609,6 +1658,25 @@ static inline __le16 ext4_rec_len_to_disk(unsigned len, unsigned blocksize)
 #define DX_HASH_HALF_MD4_UNSIGNED       4
 #define DX_HASH_TEA_UNSIGNED            5
 
+static inline u32 ext4_chksum(struct ext4_sb_info *sbi, u32 crc,
+                              const void *address, unsigned int length)
+{
+        struct {
+                struct shash_desc shash;
+                char ctx[crypto_shash_descsize(sbi->s_chksum_driver)];
+        } desc;
+        int err;
+
+        desc.shash.tfm = sbi->s_chksum_driver;
+        desc.shash.flags = 0;
+        *(u32 *)desc.ctx = crc;
+
+        err = crypto_shash_update(&desc.shash, address, length);
+        BUG_ON(err);
+
+        return *(u32 *)desc.ctx;
+}
+
 #ifdef __KERNEL__
 
 /* hash info structure used by the directory hash */
@@ -1741,7 +1809,8 @@ struct mmp_struct {
         __le16  mmp_check_interval;
 
         __le16  mmp_pad1;
-        __le32  mmp_pad2[227];
+        __le32  mmp_pad2[226];
+        __le32  mmp_checksum;           /* crc32c(uuid+mmp_block) */
 };
 
 /* arguments passed to the mmp thread */
@@ -1784,8 +1853,24 @@ struct mmpd_data {
 
 /* bitmap.c */
 extern unsigned int ext4_count_free(struct buffer_head *, unsigned);
+void ext4_inode_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
+                                struct ext4_group_desc *gdp,
+                                struct buffer_head *bh, int sz);
+int ext4_inode_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
+                                  struct ext4_group_desc *gdp,
+                                  struct buffer_head *bh, int sz);
+void ext4_block_bitmap_csum_set(struct super_block *sb, ext4_group_t group,
+                                struct ext4_group_desc *gdp,
+                                struct buffer_head *bh, int sz);
+int ext4_block_bitmap_csum_verify(struct super_block *sb, ext4_group_t group,
+                                  struct ext4_group_desc *gdp,
+                                  struct buffer_head *bh, int sz);
 
 /* balloc.c */
+extern void ext4_validate_block_bitmap(struct super_block *sb,
+                                       struct ext4_group_desc *desc,
+                                       unsigned int block_group,
+                                       struct buffer_head *bh);
 extern unsigned int ext4_block_group(struct super_block *sb,
                         ext4_fsblk_t blocknr);
 extern ext4_grpblk_t ext4_block_group_offset(struct super_block *sb,
@@ -1864,7 +1949,7 @@ extern void ext4_end_bitmap_read(struct buffer_head *bh, int uptodate);
 /* mballoc.c */
 extern long ext4_mb_stats;
 extern long ext4_mb_max_to_scan;
-extern int ext4_mb_init(struct super_block *, int);
+extern int ext4_mb_init(struct super_block *);
 extern int ext4_mb_release(struct super_block *);
 extern ext4_fsblk_t ext4_mb_new_blocks(handle_t *,
                                 struct ext4_allocation_request *, int *);
@@ -1936,6 +2021,8 @@ extern long ext4_compat_ioctl(struct file *, unsigned int, unsigned long);
 extern int ext4_ext_migrate(struct inode *);
 
 /* namei.c */
+extern int ext4_dirent_csum_verify(struct inode *inode,
+                                   struct ext4_dir_entry *dirent);
 extern int ext4_orphan_add(handle_t *, struct inode *);
 extern int ext4_orphan_del(handle_t *, struct inode *);
 extern int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
@@ -1950,6 +2037,10 @@ extern int ext4_group_extend(struct super_block *sb,
 extern int ext4_resize_fs(struct super_block *sb, ext4_fsblk_t n_blocks_count);
 
 /* super.c */
+extern int ext4_superblock_csum_verify(struct super_block *sb,
+                                       struct ext4_super_block *es);
+extern void ext4_superblock_csum_set(struct super_block *sb,
+                                     struct ext4_super_block *es);
 extern void *ext4_kvmalloc(size_t size, gfp_t flags);
 extern void *ext4_kvzalloc(size_t size, gfp_t flags);
 extern void ext4_kvfree(void *ptr);
@@ -2025,10 +2116,17 @@ extern void ext4_used_dirs_set(struct super_block *sb,
                                 struct ext4_group_desc *bg, __u32 count);
 extern void ext4_itable_unused_set(struct super_block *sb,
                                    struct ext4_group_desc *bg, __u32 count);
-extern __le16 ext4_group_desc_csum(struct ext4_sb_info *sbi, __u32 group,
-                                   struct ext4_group_desc *gdp);
-extern int ext4_group_desc_csum_verify(struct ext4_sb_info *sbi, __u32 group,
+extern int ext4_group_desc_csum_verify(struct super_block *sb, __u32 group,
                                        struct ext4_group_desc *gdp);
+extern void ext4_group_desc_csum_set(struct super_block *sb, __u32 group,
+                                     struct ext4_group_desc *gdp);
+
+static inline int ext4_has_group_desc_csum(struct super_block *sb)
+{
+        return EXT4_HAS_RO_COMPAT_FEATURE(sb,
+                                          EXT4_FEATURE_RO_COMPAT_GDT_CSUM |
+                                          EXT4_FEATURE_RO_COMPAT_METADATA_CSUM);
+}
 
 static inline ext4_fsblk_t ext4_blocks_count(struct ext4_super_block *es)
 {
@@ -2225,6 +2323,9 @@ static inline void ext4_unlock_group(struct super_block *sb,
 
 static inline void ext4_mark_super_dirty(struct super_block *sb)
 {
+        struct ext4_super_block *es = EXT4_SB(sb)->s_es;
+
+        ext4_superblock_csum_set(sb, es);
         if (EXT4_SB(sb)->s_journal == NULL)
                 sb->s_dirt =1;
 }
@@ -2314,6 +2415,9 @@ extern int ext4_bio_write_page(struct ext4_io_submit *io,
 
 /* mmp.c */
 extern int ext4_multi_mount_protect(struct super_block *, ext4_fsblk_t);
+extern void ext4_mmp_csum_set(struct super_block *sb, struct mmp_struct *mmp);
+extern int ext4_mmp_csum_verify(struct super_block *sb,
+                                struct mmp_struct *mmp);
 
 /* BH_Uninit flag: blocks are allocated but uninitialized on disk */
 enum ext4_state_bits {