Return-Path: Received: from bhuna.collabora.co.uk ([46.235.227.227]:45604 "EHLO bhuna.collabora.co.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725986AbeIYECz (ORCPT ); Tue, 25 Sep 2018 00:02:55 -0400 From: Gabriel Krisman Bertazi To: tytso@mit.edu Cc: linux-ext4@vger.kernel.org, Gabriel Krisman Bertazi Subject: [PATCH RESEND v2 24/25] ext4: Implement EXT4_CASEFOLD_FL flag Date: Mon, 24 Sep 2018 17:56:54 -0400 Message-Id: <20180924215655.3676-25-krisman@collabora.co.uk> In-Reply-To: <20180924215655.3676-1-krisman@collabora.co.uk> References: <20180924215655.3676-1-krisman@collabora.co.uk> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-ext4-owner@vger.kernel.org List-ID: Casefold is a flag applied to directories and inherited by its children which states that the directory requires case-insensitive searches. This flag can only be enabled on empty directories for filesystems that support the encoding feature, thus preventing collision of file names that only differ by case. Enconding-awareness is also required because we consider the casefold operation not be defined for opaque byte sequences. Changes since last version: - Moved the CASEFOLD_FL to prevent collision with reserved Verity flag. Signed-off-by: Gabriel Krisman Bertazi --- fs/ext4/dir.c | 30 ++++++++++++++++++++++-------- fs/ext4/ext4.h | 7 ++++--- fs/ext4/hash.c | 6 +++++- fs/ext4/inode.c | 4 +++- fs/ext4/ioctl.c | 18 ++++++++++++++++++ fs/ext4/namei.c | 13 ++++++++++--- include/linux/fs.h | 2 ++ 7 files changed, 64 insertions(+), 16 deletions(-) diff --git a/fs/ext4/dir.c b/fs/ext4/dir.c index 37a36cdadaaf..ab3d7d40e7db 100644 --- a/fs/ext4/dir.c +++ b/fs/ext4/dir.c @@ -670,6 +670,10 @@ static int ext4_d_compare(const struct dentry *dentry, unsigned int len, { struct nls_table *charset = EXT4_SB(dentry->d_sb)->encoding; + if (IS_CASEFOLDED(dentry->d_parent->d_inode)) + return nls_strncasecmp(charset, str, len, name->name, + name->len); + return nls_strncmp(charset, str, len, name->name, name->len); } @@ -679,16 +683,26 @@ static int ext4_d_hash(const struct dentry *dentry, struct qstr *q) unsigned char *norm; int len, ret = 0; - /* If normalization is TYPE_PLAIN, we can just reuse the vfs - * hash. */ - if (IS_NORMALIZATION_TYPE_ALL_PLAIN(charset)) - return 0; + if (!IS_CASEFOLDED(dentry->d_inode)) { - norm = kmalloc(PATH_MAX, GFP_ATOMIC); - if (!norm) - return -ENOMEM; + /* If normalization is TYPE_PLAIN, we can just reuse the + * VFS hash. + */ + if (IS_NORMALIZATION_TYPE_ALL_PLAIN(charset)) + return 0; - len = nls_normalize(charset, q->name, q->len, norm, PATH_MAX); + norm = kmalloc(PATH_MAX, GFP_ATOMIC); + if (!norm) + return -ENOMEM; + + len = nls_normalize(charset, q->name, q->len, norm, PATH_MAX); + } else { + norm = kmalloc(PATH_MAX, GFP_ATOMIC); + if (!norm) + return -ENOMEM; + + len = nls_casefold(charset, q->name, q->len, norm, PATH_MAX); + } if (len < 0) { ret = -EINVAL; diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index 586e733c8915..3db434d61717 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -409,10 +409,11 @@ struct flex_groups { #define EXT4_EOFBLOCKS_FL 0x00400000 /* Blocks allocated beyond EOF */ #define EXT4_INLINE_DATA_FL 0x10000000 /* Inode has inline data. */ #define EXT4_PROJINHERIT_FL 0x20000000 /* Create with parents projid */ +#define EXT4_CASEFOLD_FL 0x40000000 /* Casefolded file */ #define EXT4_RESERVED_FL 0x80000000 /* reserved for ext4 lib */ -#define EXT4_FL_USER_VISIBLE 0x304BDFFF /* User visible flags */ -#define EXT4_FL_USER_MODIFIABLE 0x204BC0FF /* User modifiable flags */ +#define EXT4_FL_USER_VISIBLE 0x704BDFFF /* User visible flags */ +#define EXT4_FL_USER_MODIFIABLE 0x604BC0FF /* User modifiable flags */ /* Flags we can manipulate with through EXT4_IOC_FSSETXATTR */ #define EXT4_FL_XFLAG_VISIBLE (EXT4_SYNC_FL | \ @@ -427,7 +428,7 @@ struct flex_groups { EXT4_SYNC_FL | EXT4_NODUMP_FL | EXT4_NOATIME_FL |\ EXT4_NOCOMPR_FL | EXT4_JOURNAL_DATA_FL |\ EXT4_NOTAIL_FL | EXT4_DIRSYNC_FL |\ - EXT4_PROJINHERIT_FL) + EXT4_PROJINHERIT_FL | EXT4_CASEFOLD_FL) /* Flags that are appropriate for regular files (all but dir-specific ones). */ #define EXT4_REG_FLMASK (~(EXT4_DIRSYNC_FL | EXT4_TOPDIR_FL)) diff --git a/fs/ext4/hash.c b/fs/ext4/hash.c index 1b3c9a492b14..a8443f43e283 100644 --- a/fs/ext4/hash.c +++ b/fs/ext4/hash.c @@ -282,7 +282,11 @@ int ext4fs_dirhash(const struct inode *dir, const char *name, int len, if (!buff) return -1; - dlen = nls_normalize(charset, name, len, buff, PATH_MAX); + if (!IS_CASEFOLDED(dir)) + dlen = nls_normalize(charset, name, len, buff, + PATH_MAX); + else + dlen = nls_casefold(charset, name, len, buff, PATH_MAX); if (dlen < 0) { kfree(buff); diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index f73f18a68165..374a20cce28e 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -4713,9 +4713,11 @@ void ext4_set_inode_flags(struct inode *inode) new_fl |= S_DAX; if (flags & EXT4_ENCRYPT_FL) new_fl |= S_ENCRYPTED; + if (flags & EXT4_CASEFOLD_FL) + new_fl |= S_CASEFOLD; inode_set_flags(inode, new_fl, S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC|S_DAX| - S_ENCRYPTED); + S_ENCRYPTED|S_CASEFOLD); } static blkcnt_t ext4_inode_blocks(struct ext4_inode *raw_inode, diff --git a/fs/ext4/ioctl.c b/fs/ext4/ioctl.c index a7074115d6f6..f57e5460cf23 100644 --- a/fs/ext4/ioctl.c +++ b/fs/ext4/ioctl.c @@ -210,6 +210,7 @@ static int ext4_ioctl_setflags(struct inode *inode, struct ext4_iloc iloc; unsigned int oldflags, mask, i; unsigned int jflag; + struct super_block *sb = inode->i_sb; /* Is it quota file? Do not allow user to mess with it */ if (ext4_is_quota_file(inode)) @@ -254,6 +255,23 @@ static int ext4_ioctl_setflags(struct inode *inode, goto flags_out; } + if ((flags ^ oldflags) & EXT4_CASEFOLD_FL) { + if (!ext4_has_feature_ioencoding(sb)) { + err = -EOPNOTSUPP; + goto flags_out; + } + + if (!S_ISDIR(inode->i_mode)) { + err = -ENOTDIR; + goto flags_out; + } + + if (!ext4_empty_dir(inode)) { + err = -ENOTEMPTY; + goto flags_out; + } + } + handle = ext4_journal_start(inode, EXT4_HT_INODE, 1); if (IS_ERR(handle)) { err = PTR_ERR(handle); diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c index be0c2e5ae2e0..c77330a25b3a 100644 --- a/fs/ext4/namei.c +++ b/fs/ext4/namei.c @@ -1277,9 +1277,16 @@ static inline bool ext4_match(const struct inode *parent, #ifdef CONFIG_NLS if (sbi->encoding) { - return !nls_strncmp(sbi->encoding, - de->name, de->name_len, - f.disk_name.name, f.disk_name.len); + if (!IS_CASEFOLDED(parent)) + return !nls_strncmp(sbi->encoding, + de->name, de->name_len, + fname->disk_name.name, + fname->disk_name.len); + else + return !nls_strncasecmp(sbi->encoding, + de->name, de->name_len, + fname->disk_name.name, + fname->disk_name.len); } #endif diff --git a/include/linux/fs.h b/include/linux/fs.h index d78d146a98da..1a763f27268f 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -1877,6 +1877,7 @@ struct super_operations { #define S_DAX 0 /* Make all the DAX code disappear */ #endif #define S_ENCRYPTED 16384 /* Encrypted file (using fs/crypto/) */ +#define S_CASEFOLD 32768 /* Casefolded file */ /* * Note that nosuid etc flags are inode-specific: setting some file-system @@ -1917,6 +1918,7 @@ static inline bool sb_rdonly(const struct super_block *sb) { return sb->s_flags #define IS_NOSEC(inode) ((inode)->i_flags & S_NOSEC) #define IS_DAX(inode) ((inode)->i_flags & S_DAX) #define IS_ENCRYPTED(inode) ((inode)->i_flags & S_ENCRYPTED) +#define IS_CASEFOLDED(inode) ((inode)->i_flags & S_CASEFOLD) #define IS_WHITEOUT(inode) (S_ISCHR(inode->i_mode) && \ (inode)->i_rdev == WHITEOUT_DEV) -- 2.19.0