diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index 2a2e6ed9aab4fb9f580f1b651f2d7e3333537c8b..c1504c471fef99526c440a0a5301900e813def2f 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -1313,7 +1313,9 @@ struct ext4_super_block {
__u8 s_first_error_time_hi;
__u8 s_last_error_time_hi;
__u8 s_pad[2];
- __le32 s_reserved[96]; /* Padding to the end of the block */
+ __le16 s_encoding; /* Filename charset encoding */
+ __le16 s_encoding_flags; /* Filename charset encoding flags */
+ __le32 s_reserved[95]; /* Padding to the end of the block */
__le32 s_checksum; /* crc32c(superblock) */
};
@@ -1338,6 +1340,16 @@ struct ext4_super_block {
/* Number of quota types we support */
#define EXT4_MAXQUOTAS 3
+#define EXT4_ENC_UTF8_12_1 1
+
+/*
+ * Flags for ext4_sb_info.s_encoding_flags.
+ */
+#define EXT4_ENC_STRICT_MODE_FL (1 << 0)
+
+#define ext4_has_strict_mode(sbi) \
+ (sbi->s_encoding_flags & EXT4_ENC_STRICT_MODE_FL)
+
/*
* fourth extended-fs super-block data in memory
*/
@@ -1387,6 +1399,10 @@ struct ext4_sb_info {
struct kobject s_kobj;
struct completion s_kobj_unregister;
struct super_block *s_sb;
+#ifdef CONFIG_UNICODE
+ struct unicode_map *s_encoding;
+ __u16 s_encoding_flags;
+#endif
/* Journaling */
struct journal_s *s_journal;
@@ -1660,6 +1676,7 @@ static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
#define EXT4_FEATURE_INCOMPAT_LARGEDIR 0x4000 /* >2GB or 3-lvl htree */
#define EXT4_FEATURE_INCOMPAT_INLINE_DATA 0x8000 /* data in inode */
#define EXT4_FEATURE_INCOMPAT_ENCRYPT 0x10000
+#define EXT4_FEATURE_INCOMPAT_CASEFOLD 0x20000
extern void ext4_update_dynamic_rev(struct super_block *sb);
@@ -1753,6 +1770,7 @@ EXT4_FEATURE_INCOMPAT_FUNCS(csum_seed, CSUM_SEED)
EXT4_FEATURE_INCOMPAT_FUNCS(largedir, LARGEDIR)
EXT4_FEATURE_INCOMPAT_FUNCS(inline_data, INLINE_DATA)
EXT4_FEATURE_INCOMPAT_FUNCS(encrypt, ENCRYPT)
+EXT4_FEATURE_INCOMPAT_FUNCS(casefold, CASEFOLD)
#define EXT2_FEATURE_COMPAT_SUPP EXT4_FEATURE_COMPAT_EXT_ATTR
#define EXT2_FEATURE_INCOMPAT_SUPP (EXT4_FEATURE_INCOMPAT_FILETYPE| \
@@ -1780,6 +1798,7 @@ EXT4_FEATURE_INCOMPAT_FUNCS(encrypt, ENCRYPT)
EXT4_FEATURE_INCOMPAT_MMP | \
EXT4_FEATURE_INCOMPAT_INLINE_DATA | \
EXT4_FEATURE_INCOMPAT_ENCRYPT | \
+ EXT4_FEATURE_INCOMPAT_CASEFOLD | \
EXT4_FEATURE_INCOMPAT_CSUM_SEED | \
EXT4_FEATURE_INCOMPAT_LARGEDIR)
#define EXT4_FEATURE_RO_COMPAT_SUPP (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 184944d4d8d1a5828e27f7f265317086a32f9a08..c1b02c3a5a681d0aab1ddd6dff51ab7c7575ac29 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -42,6 +42,7 @@
#include <linux/cleancache.h>
#include <linux/uaccess.h>
#include <linux/iversion.h>
+#include <linux/unicode.h>
#include <linux/kthread.h>
#include <linux/freezer.h>
@@ -1054,6 +1055,9 @@ static void ext4_put_super(struct super_block *sb)
crypto_free_shash(sbi->s_chksum_driver);
kfree(sbi->s_blockgroup_lock);
fs_put_dax(sbi->s_daxdev);
+#ifdef CONFIG_UNICODE
+ utf8_unload(sbi->s_encoding);
+#endif
kfree(sbi);
}
@@ -1750,6 +1754,36 @@ static const struct mount_opts {
{Opt_err, 0, 0}
};
+#ifdef CONFIG_UNICODE
+static const struct ext4_sb_encodings {
+ __u16 magic;
+ char *name;
+ char *version;
+} ext4_sb_encoding_map[] = {
+ {EXT4_ENC_UTF8_12_1, "utf8", "12.1.0"},
+};
+
+static int ext4_sb_read_encoding(const struct ext4_super_block *es,
+ const struct ext4_sb_encodings **encoding,
+ __u16 *flags)
+{
+ __u16 magic = le16_to_cpu(es->s_encoding);
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(ext4_sb_encoding_map); i++)
+ if (magic == ext4_sb_encoding_map[i].magic)
+ break;
+
+ if (i >= ARRAY_SIZE(ext4_sb_encoding_map))
+ return -EINVAL;
+
+ *encoding = &ext4_sb_encoding_map[i];
+ *flags = le16_to_cpu(es->s_encoding_flags);
+
+ return 0;
+}
+#endif
+
static int handle_mount_opt(struct super_block *sb, char *opt, int token,
substring_t *args, unsigned long *journal_devnum,
unsigned int *journal_ioprio, int is_remount)
@@ -2880,6 +2914,15 @@ static int ext4_feature_set_ok(struct super_block *sb, int readonly)
return 0;
}
+#ifndef CONFIG_UNICODE
+ if (ext4_has_feature_casefold(sb)) {
+ ext4_msg(sb, KERN_ERR,
+ "Filesystem with casefold feature cannot be "
+ "mounted without CONFIG_UNICODE");
+ return 0;
+ }
+#endif
+
if (readonly)
return 1;
@@ -3770,6 +3813,43 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent)
&journal_ioprio, 0))
goto failed_mount;
+#ifdef CONFIG_UNICODE
+ if (ext4_has_feature_casefold(sb) && !sbi->s_encoding) {
+ const struct ext4_sb_encodings *encoding_info;
+ struct unicode_map *encoding;
+ __u16 encoding_flags;
+
+ if (ext4_has_feature_encrypt(sb)) {
+ ext4_msg(sb, KERN_ERR,
+ "Can't mount with encoding and encryption");
+ goto failed_mount;
+ }
+
+ if (ext4_sb_read_encoding(es, &encoding_info,
+ &encoding_flags)) {
+ ext4_msg(sb, KERN_ERR,
+ "Encoding requested by superblock is unknown");
+ goto failed_mount;
+ }
+
+ encoding = utf8_load(encoding_info->version);
+ if (IS_ERR(encoding)) {
+ ext4_msg(sb, KERN_ERR,
+ "can't mount with superblock charset: %s-%s "
+ "not supported by the kernel. flags: 0x%x.",
+ encoding_info->name, encoding_info->version,
+ encoding_flags);
+ goto failed_mount;
+ }
+ ext4_msg(sb, KERN_INFO,"Using encoding defined by superblock: "
+ "%s-%s with flags 0x%hx", encoding_info->name,
+ encoding_info->version?:"\b", encoding_flags);
+
+ sbi->s_encoding = encoding;
+ sbi->s_encoding_flags = encoding_flags;
+ }
+#endif
+
if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
printk_once(KERN_WARNING "EXT4-fs: Warning: mounting "
"with data=journal disables delayed "
@@ -4586,6 +4666,11 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent)
failed_mount:
if (sbi->s_chksum_driver)
crypto_free_shash(sbi->s_chksum_driver);
+
+#ifdef CONFIG_UNICODE
+ utf8_unload(sbi->s_encoding);
+#endif
+
#ifdef CONFIG_QUOTA
for (i = 0; i < EXT4_MAXQUOTAS; i++)
kfree(sbi->s_qf_names[i]);