diff options
Diffstat (limited to 'fs/exfat/namei.c')
| -rw-r--r-- | fs/exfat/namei.c | 1380 |
1 files changed, 1380 insertions, 0 deletions
diff --git a/fs/exfat/namei.c b/fs/exfat/namei.c new file mode 100644 index 000000000000..b617bebc3d0f --- /dev/null +++ b/fs/exfat/namei.c @@ -0,0 +1,1380 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (C) 2012-2013 Samsung Electronics Co., Ltd. + */ + +#include <linux/iversion.h> +#include <linux/namei.h> +#include <linux/slab.h> +#include <linux/buffer_head.h> +#include <linux/nls.h> + +#include "exfat_raw.h" +#include "exfat_fs.h" + +static inline unsigned long exfat_d_version(struct dentry *dentry) +{ + return (unsigned long) dentry->d_fsdata; +} + +static inline void exfat_d_version_set(struct dentry *dentry, + unsigned long version) +{ + dentry->d_fsdata = (void *) version; +} + +/* + * If new entry was created in the parent, it could create the 8.3 alias (the + * shortname of logname). So, the parent may have the negative-dentry which + * matches the created 8.3 alias. + * + * If it happened, the negative dentry isn't actually negative anymore. So, + * drop it. + */ +static int exfat_d_revalidate(struct dentry *dentry, unsigned int flags) +{ + int ret; + + if (flags & LOOKUP_RCU) + return -ECHILD; + + /* + * This is not negative dentry. Always valid. + * + * Note, rename() to existing directory entry will have ->d_inode, and + * will use existing name which isn't specified name by user. + * + * We may be able to drop this positive dentry here. But dropping + * positive dentry isn't good idea. So it's unsupported like + * rename("filename", "FILENAME") for now. + */ + if (d_really_is_positive(dentry)) + return 1; + + /* + * Drop the negative dentry, in order to make sure to use the case + * sensitive name which is specified by user if this is for creation. + */ + if (flags & (LOOKUP_CREATE | LOOKUP_RENAME_TARGET)) + return 0; + + spin_lock(&dentry->d_lock); + ret = inode_eq_iversion(d_inode(dentry->d_parent), + exfat_d_version(dentry)); + spin_unlock(&dentry->d_lock); + return ret; +} + +/* returns the length of a struct qstr, ignoring trailing dots if necessary */ +static unsigned int exfat_striptail_len(unsigned int len, const char *name, + bool keep_last_dots) +{ + if (!keep_last_dots) { + while (len && name[len - 1] == '.') + len--; + } + return len; +} + +/* + * Compute the hash for the exfat name corresponding to the dentry. If the name + * is invalid, we leave the hash code unchanged so that the existing dentry can + * be used. The exfat fs routines will return ENOENT or EINVAL as appropriate. + */ +static int exfat_d_hash(const struct dentry *dentry, struct qstr *qstr) +{ + struct super_block *sb = dentry->d_sb; + struct nls_table *t = EXFAT_SB(sb)->nls_io; + const unsigned char *name = qstr->name; + unsigned int len = exfat_striptail_len(qstr->len, qstr->name, + EXFAT_SB(sb)->options.keep_last_dots); + unsigned long hash = init_name_hash(dentry); + int i, charlen; + wchar_t c; + + for (i = 0; i < len; i += charlen) { + charlen = t->char2uni(&name[i], len - i, &c); + if (charlen < 0) + return charlen; + hash = partial_name_hash(exfat_toupper(sb, c), hash); + } + + qstr->hash = end_name_hash(hash); + return 0; +} + +static int exfat_d_cmp(const struct dentry *dentry, unsigned int len, + const char *str, const struct qstr *name) +{ + struct super_block *sb = dentry->d_sb; + struct nls_table *t = EXFAT_SB(sb)->nls_io; + unsigned int alen = exfat_striptail_len(name->len, name->name, + EXFAT_SB(sb)->options.keep_last_dots); + unsigned int blen = exfat_striptail_len(len, str, + EXFAT_SB(sb)->options.keep_last_dots); + wchar_t c1, c2; + int charlen, i; + + if (alen != blen) + return 1; + + for (i = 0; i < len; i += charlen) { + charlen = t->char2uni(&name->name[i], alen - i, &c1); + if (charlen < 0) + return 1; + if (charlen != t->char2uni(&str[i], blen - i, &c2)) + return 1; + + if (exfat_toupper(sb, c1) != exfat_toupper(sb, c2)) + return 1; + } + + return 0; +} + +const struct dentry_operations exfat_dentry_ops = { + .d_revalidate = exfat_d_revalidate, + .d_hash = exfat_d_hash, + .d_compare = exfat_d_cmp, +}; + +static int exfat_utf8_d_hash(const struct dentry *dentry, struct qstr *qstr) +{ + struct super_block *sb = dentry->d_sb; + const unsigned char *name = qstr->name; + unsigned int len = exfat_striptail_len(qstr->len, qstr->name, + EXFAT_SB(sb)->options.keep_last_dots); + unsigned long hash = init_name_hash(dentry); + int i, charlen; + unicode_t u; + + for (i = 0; i < len; i += charlen) { + charlen = utf8_to_utf32(&name[i], len - i, &u); + if (charlen < 0) + return charlen; + + /* + * exfat_toupper() works only for code points up to the U+FFFF. + */ + hash = partial_name_hash(u <= 0xFFFF ? exfat_toupper(sb, u) : u, + hash); + } + + qstr->hash = end_name_hash(hash); + return 0; +} + +static int exfat_utf8_d_cmp(const struct dentry *dentry, unsigned int len, + const char *str, const struct qstr *name) +{ + struct super_block *sb = dentry->d_sb; + unsigned int alen = exfat_striptail_len(name->len, name->name, + EXFAT_SB(sb)->options.keep_last_dots); + unsigned int blen = exfat_striptail_len(len, str, + EXFAT_SB(sb)->options.keep_last_dots); + + unicode_t u_a, u_b; + int charlen, i; + + if (alen != blen) + return 1; + + for (i = 0; i < alen; i += charlen) { + charlen = utf8_to_utf32(&name->name[i], alen - i, &u_a); + if (charlen < 0) + return 1; + if (charlen != utf8_to_utf32(&str[i], blen - i, &u_b)) + return 1; + + if (u_a <= 0xFFFF && u_b <= 0xFFFF) { + if (exfat_toupper(sb, u_a) != exfat_toupper(sb, u_b)) + return 1; + } else { + if (u_a != u_b) + return 1; + } + } + + return 0; +} + +const struct dentry_operations exfat_utf8_dentry_ops = { + .d_revalidate = exfat_d_revalidate, + .d_hash = exfat_utf8_d_hash, + .d_compare = exfat_utf8_d_cmp, +}; + +/* used only in search empty_slot() */ +#define CNT_UNUSED_NOHIT (-1) +#define CNT_UNUSED_HIT (-2) +/* search EMPTY CONTINUOUS "num_entries" entries */ +static int exfat_search_empty_slot(struct super_block *sb, + struct exfat_hint_femp *hint_femp, struct exfat_chain *p_dir, + int num_entries) +{ + int i, dentry, num_empty = 0; + int dentries_per_clu; + unsigned int type; + struct exfat_chain clu; + struct exfat_dentry *ep; + struct exfat_sb_info *sbi = EXFAT_SB(sb); + struct buffer_head *bh; + + dentries_per_clu = sbi->dentries_per_clu; + + if (hint_femp->eidx != EXFAT_HINT_NONE) { + dentry = hint_femp->eidx; + if (num_entries <= hint_femp->count) { + hint_femp->eidx = EXFAT_HINT_NONE; + return dentry; + } + + exfat_chain_dup(&clu, &hint_femp->cur); + } else { + exfat_chain_dup(&clu, p_dir); + dentry = 0; + } + + while (clu.dir != EXFAT_EOF_CLUSTER) { + i = dentry & (dentries_per_clu - 1); + + for (; i < dentries_per_clu; i++, dentry++) { + ep = exfat_get_dentry(sb, &clu, i, &bh); + if (!ep) + return -EIO; + type = exfat_get_entry_type(ep); + brelse(bh); + + if (type == TYPE_UNUSED || type == TYPE_DELETED) { + num_empty++; + if (hint_femp->eidx == EXFAT_HINT_NONE) { + hint_femp->eidx = dentry; + hint_femp->count = CNT_UNUSED_NOHIT; + exfat_chain_set(&hint_femp->cur, + clu.dir, clu.size, clu.flags); + } + + if (type == TYPE_UNUSED && + hint_femp->count != CNT_UNUSED_HIT) + hint_femp->count = CNT_UNUSED_HIT; + } else { + if (hint_femp->eidx != EXFAT_HINT_NONE && + hint_femp->count == CNT_UNUSED_HIT) { + /* unused empty group means + * an empty group which includes + * unused dentry + */ + exfat_fs_error(sb, + "found bogus dentry(%d) beyond unused empty group(%d) (start_clu : %u, cur_clu : %u)", + dentry, hint_femp->eidx, + p_dir->dir, clu.dir); + return -EIO; + } + + num_empty = 0; + hint_femp->eidx = EXFAT_HINT_NONE; + } + + if (num_empty >= num_entries) { + /* found and invalidate hint_femp */ + hint_femp->eidx = EXFAT_HINT_NONE; + return (dentry - (num_entries - 1)); + } + } + + if (clu.flags == ALLOC_NO_FAT_CHAIN) { + if (--clu.size > 0) + clu.dir++; + else + clu.dir = EXFAT_EOF_CLUSTER; + } else { + if (exfat_get_next_cluster(sb, &clu.dir)) + return -EIO; + } + } + + return -ENOSPC; +} + +static int exfat_check_max_dentries(struct inode *inode) +{ + if (EXFAT_B_TO_DEN(i_size_read(inode)) >= MAX_EXFAT_DENTRIES) { + /* + * exFAT spec allows a dir to grow up to 8388608(256MB) + * dentries + */ + return -ENOSPC; + } + return 0; +} + +/* find empty directory entry. + * if there isn't any empty slot, expand cluster chain. + */ +static int exfat_find_empty_entry(struct inode *inode, + struct exfat_chain *p_dir, int num_entries) +{ + int dentry; + unsigned int ret, last_clu; + loff_t size = 0; + struct exfat_chain clu; + struct super_block *sb = inode->i_sb; + struct exfat_sb_info *sbi = EXFAT_SB(sb); + struct exfat_inode_info *ei = EXFAT_I(inode); + struct exfat_hint_femp hint_femp; + + hint_femp.eidx = EXFAT_HINT_NONE; + + if (ei->hint_femp.eidx != EXFAT_HINT_NONE) { + hint_femp = ei->hint_femp; + ei->hint_femp.eidx = EXFAT_HINT_NONE; + } + + while ((dentry = exfat_search_empty_slot(sb, &hint_femp, p_dir, + num_entries)) < 0) { + if (dentry == -EIO) + break; + + if (exfat_check_max_dentries(inode)) + return -ENOSPC; + + /* we trust p_dir->size regardless of FAT type */ + if (exfat_find_last_cluster(sb, p_dir, &last_clu)) + return -EIO; + + /* + * Allocate new cluster to this directory + */ + exfat_chain_set(&clu, last_clu + 1, 0, p_dir->flags); + + /* allocate a cluster */ + ret = exfat_alloc_cluster(inode, 1, &clu, IS_DIRSYNC(inode)); + if (ret) + return ret; + + if (exfat_zeroed_cluster(inode, clu.dir)) + return -EIO; + + /* append to the FAT chain */ + if (clu.flags != p_dir->flags) { + /* no-fat-chain bit is disabled, + * so fat-chain should be synced with alloc-bitmap + */ + exfat_chain_cont_cluster(sb, p_dir->dir, p_dir->size); + p_dir->flags = ALLOC_FAT_CHAIN; + hint_femp.cur.flags = ALLOC_FAT_CHAIN; + } + + if (clu.flags == ALLOC_FAT_CHAIN) + if (exfat_ent_set(sb, last_clu, clu.dir)) + return -EIO; + + if (hint_femp.eidx == EXFAT_HINT_NONE) { + /* the special case that new dentry + * should be allocated from the start of new cluster + */ + hint_femp.eidx = EXFAT_B_TO_DEN_IDX(p_dir->size, sbi); + hint_femp.count = sbi->dentries_per_clu; + + exfat_chain_set(&hint_femp.cur, clu.dir, 0, clu.flags); + } + hint_femp.cur.size++; + p_dir->size++; + size = EXFAT_CLU_TO_B(p_dir->size, sbi); + + /* directory inode should be updated in here */ + i_size_write(inode, size); + ei->i_size_ondisk += sbi->cluster_size; + ei->i_size_aligned += sbi->cluster_size; + ei->flags = p_dir->flags; + inode->i_blocks += 1 << sbi->sect_per_clus_bits; + } + + return dentry; +} + +/* + * Name Resolution Functions : + * Zero if it was successful; otherwise nonzero. + */ +static int __exfat_resolve_path(struct inode *inode, const unsigned char *path, + struct exfat_chain *p_dir, struct exfat_uni_name *p_uniname, + int lookup) +{ + int namelen; + int lossy = NLS_NAME_NO_LOSSY; + struct super_block *sb = inode->i_sb; + struct exfat_sb_info *sbi = EXFAT_SB(sb); + struct exfat_inode_info *ei = EXFAT_I(inode); + int pathlen = strlen(path); + + /* + * get the length of the pathname excluding + * trailing periods, if any. + */ + namelen = exfat_striptail_len(pathlen, path, false); + if (EXFAT_SB(sb)->options.keep_last_dots) { + /* + * Do not allow the creation of files with names + * ending with period(s). + */ + if (!lookup && (namelen < pathlen)) + return -EINVAL; + namelen = pathlen; + } + if (!namelen) + return -ENOENT; + if (pathlen > (MAX_NAME_LENGTH * MAX_CHARSET_SIZE)) + return -ENAMETOOLONG; + + /* + * strip all leading spaces : + * "MS windows 7" supports leading spaces. + * So we should skip this preprocessing for compatibility. + */ + + /* file name conversion : + * If lookup case, we allow bad-name for compatibility. + */ + namelen = exfat_nls_to_utf16(sb, path, namelen, p_uniname, + &lossy); + if (namelen < 0) + return namelen; /* return error value */ + + if ((lossy && !lookup) || !namelen) + return (lossy & NLS_NAME_OVERLEN) ? -ENAMETOOLONG : -EINVAL; + + exfat_chain_set(p_dir, ei->start_clu, + EXFAT_B_TO_CLU(i_size_read(inode), sbi), ei->flags); + + return 0; +} + +static inline int exfat_resolve_path(struct inode *inode, + const unsigned char *path, struct exfat_chain *dir, + struct exfat_uni_name *uni) +{ + return __exfat_resolve_path(inode, path, dir, uni, 0); +} + +static inline int exfat_resolve_path_for_lookup(struct inode *inode, + const unsigned char *path, struct exfat_chain *dir, + struct exfat_uni_name *uni) +{ + return __exfat_resolve_path(inode, path, dir, uni, 1); +} + +static inline loff_t exfat_make_i_pos(struct exfat_dir_entry *info) +{ + return ((loff_t) info->dir.dir << 32) | (info->entry & 0xffffffff); +} + +static int exfat_add_entry(struct inode *inode, const char *path, + struct exfat_chain *p_dir, unsigned int type, + struct exfat_dir_entry *info) +{ + int ret, dentry, num_entries; + struct super_block *sb = inode->i_sb; + struct exfat_sb_info *sbi = EXFAT_SB(sb); + struct exfat_uni_name uniname; + struct exfat_chain clu; + int clu_size = 0; + unsigned int start_clu = EXFAT_FREE_CLUSTER; + + ret = exfat_resolve_path(inode, path, p_dir, &uniname); + if (ret) + goto out; + + num_entries = exfat_calc_num_entries(&uniname); + if (num_entries < 0) { + ret = num_entries; + goto out; + } + + /* exfat_find_empty_entry must be called before alloc_cluster() */ + dentry = exfat_find_empty_entry(inode, p_dir, num_entries); + if (dentry < 0) { + ret = dentry; /* -EIO or -ENOSPC */ + goto out; + } + + if (type == TYPE_DIR) { + ret = exfat_alloc_new_dir(inode, &clu); + if (ret) + goto out; + start_clu = clu.dir; + clu_size = sbi->cluster_size; + } + + /* update the directory entry */ + /* fill the dos name directory entry information of the created file. + * the first cluster is not determined yet. (0) + */ + ret = exfat_init_dir_entry(inode, p_dir, dentry, type, + start_clu, clu_size); + if (ret) + goto out; + + ret = exfat_init_ext_entry(inode, p_dir, dentry, num_entries, &uniname); + if (ret) + goto out; + + info->dir = *p_dir; + info->entry = dentry; + info->flags = ALLOC_NO_FAT_CHAIN; + info->type = type; + + if (type == TYPE_FILE) { + info->attr = ATTR_ARCHIVE; + info->start_clu = EXFAT_EOF_CLUSTER; + info->size = 0; + info->num_subdirs = 0; + } else { + info->attr = ATTR_SUBDIR; + info->start_clu = start_clu; + info->size = clu_size; + info->num_subdirs = EXFAT_MIN_SUBDIR; + } + memset(&info->crtime, 0, sizeof(info->crtime)); + memset(&info->mtime, 0, sizeof(info->mtime)); + memset(&info->atime, 0, sizeof(info->atime)); +out: + return ret; +} + +static int exfat_create(struct user_namespace *mnt_userns, struct inode *dir, + struct dentry *dentry, umode_t mode, bool excl) +{ + struct super_block *sb = dir->i_sb; + struct inode *inode; + struct exfat_chain cdir; + struct exfat_dir_entry info; + loff_t i_pos; + int err; + + mutex_lock(&EXFAT_SB(sb)->s_lock); + exfat_set_volume_dirty(sb); + err = exfat_add_entry(dir, dentry->d_name.name, &cdir, TYPE_FILE, + &info); + if (err) + goto unlock; + + inode_inc_iversion(dir); + dir->i_ctime = dir->i_mtime = current_time(dir); + if (IS_DIRSYNC(dir)) + exfat_sync_inode(dir); + else + mark_inode_dirty(dir); + + i_pos = exfat_make_i_pos(&info); + inode = exfat_build_inode(sb, &info, i_pos); + err = PTR_ERR_OR_ZERO(inode); + if (err) + goto unlock; + + inode_inc_iversion(inode); + inode->i_mtime = inode->i_atime = inode->i_ctime = + EXFAT_I(inode)->i_crtime = current_time(inode); + exfat_truncate_atime(&inode->i_atime); + /* timestamp is already written, so mark_inode_dirty() is unneeded. */ + + d_instantiate(dentry, inode); +unlock: + mutex_unlock(&EXFAT_SB(sb)->s_lock); + return err; +} + +/* lookup a file */ +static int exfat_find(struct inode *dir, struct qstr *qname, + struct exfat_dir_entry *info) +{ + int ret, dentry, num_entries, count; + struct exfat_chain cdir; + struct exfat_uni_name uni_name; + struct super_block *sb = dir->i_sb; + struct exfat_sb_info *sbi = EXFAT_SB(sb); + struct exfat_inode_info *ei = EXFAT_I(dir); + struct exfat_dentry *ep, *ep2; + struct exfat_entry_set_cache *es; + /* for optimized dir & entry to prevent long traverse of cluster chain */ + struct exfat_hint hint_opt; + + if (qname->len == 0) + return -ENOENT; + + /* check the validity of directory name in the given pathname */ + ret = exfat_resolve_path_for_lookup(dir, qname->name, &cdir, &uni_name); + if (ret) + return ret; + + num_entries = exfat_calc_num_entries(&uni_name); + if (num_entries < 0) + return num_entries; + + /* check the validation of hint_stat and initialize it if required */ + if (ei->version != (inode_peek_iversion_raw(dir) & 0xffffffff)) { + ei->hint_stat.clu = cdir.dir; + ei->hint_stat.eidx = 0; + ei->version = (inode_peek_iversion_raw(dir) & 0xffffffff); + ei->hint_femp.eidx = EXFAT_HINT_NONE; + } + + /* search the file name for directories */ + dentry = exfat_find_dir_entry(sb, ei, &cdir, &uni_name, + num_entries, TYPE_ALL, &hint_opt); + + if (dentry < 0) + return dentry; /* -error value */ + + info->dir = cdir; + info->entry = dentry; + info->num_subdirs = 0; + + /* adjust cdir to the optimized value */ + cdir.dir = hint_opt.clu; + if (cdir.flags & ALLOC_NO_FAT_CHAIN) + cdir.size -= dentry / sbi->dentries_per_clu; + dentry = hint_opt.eidx; + es = exfat_get_dentry_set(sb, &cdir, dentry, ES_2_ENTRIES); + if (!es) + return -EIO; + ep = exfat_get_dentry_cached(es, 0); + ep2 = exfat_get_dentry_cached(es, 1); + + info->type = exfat_get_entry_type(ep); + info->attr = le16_to_cpu(ep->dentry.file.attr); + info->size = le64_to_cpu(ep2->dentry.stream.valid_size); + if ((info->type == TYPE_FILE) && (info->size == 0)) { + info->flags = ALLOC_NO_FAT_CHAIN; + info->start_clu = EXFAT_EOF_CLUSTER; + } else { + info->flags = ep2->dentry.stream.flags; + info->start_clu = + le32_to_cpu(ep2->dentry.stream.start_clu); + } + + exfat_get_entry_time(sbi, &info->crtime, + ep->dentry.file.create_tz, + ep->dentry.file.create_time, + ep->dentry.file.create_date, + ep->dentry.file.create_time_cs); + exfat_get_entry_time(sbi, &info->mtime, + ep->dentry.file.modify_tz, + ep->dentry.file.modify_time, + ep->dentry.file.modify_date, + ep->dentry.file.modify_time_cs); + exfat_get_entry_time(sbi, &info->atime, + ep->dentry.file.access_tz, + ep->dentry.file.access_time, + ep->dentry.file.access_date, + 0); + exfat_free_dentry_set(es, false); + + if (ei->start_clu == EXFAT_FREE_CLUSTER) { + exfat_fs_error(sb, + "non-zero size file starts with zero cluster (size : %llu, p_dir : %u, entry : 0x%08x)", + i_size_read(dir), ei->dir.dir, ei->entry); + return -EIO; + } + + if (info->type == TYPE_DIR) { + exfat_chain_set(&cdir, info->start_clu, + EXFAT_B_TO_CLU(info->size, sbi), info->flags); + count = exfat_count_dir_entries(sb, &cdir); + if (count < 0) + return -EIO; + + info->num_subdirs = count + EXFAT_MIN_SUBDIR; + } + return 0; +} + +static int exfat_d_anon_disconn(struct dentry *dentry) +{ + return IS_ROOT(dentry) && (dentry->d_flags & DCACHE_DISCONNECTED); +} + +static struct dentry *exfat_lookup(struct inode *dir, struct dentry *dentry, + unsigned int flags) +{ + struct super_block *sb = dir->i_sb; + struct inode *inode; + struct dentry *alias; + struct exfat_dir_entry info; + int err; + loff_t i_pos; + mode_t i_mode; + + mutex_lock(&EXFAT_SB(sb)->s_lock); + err = exfat_find(dir, &dentry->d_name, &info); + if (err) { + if (err == -ENOENT) { + inode = NULL; + goto out; + } + goto unlock; + } + + i_pos = exfat_make_i_pos(&info); + inode = exfat_build_inode(sb, &info, i_pos); + err = PTR_ERR_OR_ZERO(inode); + if (err) + goto unlock; + + i_mode = inode->i_mode; + alias = d_find_alias(inode); + + /* + * Checking "alias->d_parent == dentry->d_parent" to make sure + * FS is not corrupted (especially double linked dir). + */ + if (alias && alias->d_parent == dentry->d_parent && + !exfat_d_anon_disconn(alias)) { + + /* + * Unhashed alias is able to exist because of revalidate() + * called by lookup_fast. You can easily make this status + * by calling create and lookup concurrently + * In such case, we reuse an alias instead of new dentry + */ + if (d_unhashed(alias)) { + WARN_ON(alias->d_name.hash_len != + dentry->d_name.hash_len); + exfat_info(sb, "rehashed a dentry(%p) in read lookup", + alias); + d_drop(dentry); + d_rehash(alias); + } else if (!S_ISDIR(i_mode)) { + /* + * This inode has non anonymous-DCACHE_DISCONNECTED + * dentry. This means, the user did ->lookup() by an + * another name (longname vs 8.3 alias of it) in past. + * + * Switch to new one for reason of locality if possible. + */ + d_move(alias, dentry); + } + iput(inode); + mutex_unlock(&EXFAT_SB(sb)->s_lock); + return alias; + } + dput(alias); +out: + mutex_unlock(&EXFAT_SB(sb)->s_lock); + if (!inode) + exfat_d_version_set(dentry, inode_query_iversion(dir)); + + return d_splice_alias(inode, dentry); +unlock: + mutex_unlock(&EXFAT_SB(sb)->s_lock); + return ERR_PTR(err); +} + +/* remove an entry, BUT don't truncate */ +static int exfat_unlink(struct inode *dir, struct dentry *dentry) +{ + struct exfat_chain cdir; + struct exfat_dentry *ep; + struct super_block *sb = dir->i_sb; + struct inode *inode = dentry->d_inode; + struct exfat_inode_info *ei = EXFAT_I(inode); + struct buffer_head *bh; + int num_entries, entry, err = 0; + + mutex_lock(&EXFAT_SB(sb)->s_lock); + exfat_chain_dup(&cdir, &ei->dir); + entry = ei->entry; + if (ei->dir.dir == DIR_DELETED) { + exfat_err(sb, "abnormal access to deleted dentry"); + err = -ENOENT; + goto unlock; + } + + ep = exfat_get_dentry(sb, &cdir, entry, &bh); + if (!ep) { + err = -EIO; + goto unlock; + } + num_entries = exfat_count_ext_entries(sb, &cdir, entry, ep); + if (num_entries < 0) { + err = -EIO; + brelse(bh); + goto unlock; + } + num_entries++; + brelse(bh); + + exfat_set_volume_dirty(sb); + /* update the directory entry */ + if (exfat_remove_entries(dir, &cdir, entry, 0, num_entries)) { + err = -EIO; + goto unlock; + } + + /* This doesn't modify ei */ + ei->dir.dir = DIR_DELETED; + + inode_inc_iversion(dir); + dir->i_mtime = dir->i_atime = current_time(dir); + exfat_truncate_atime(&dir->i_atime); + if (IS_DIRSYNC(dir)) + exfat_sync_inode(dir); + else + mark_inode_dirty(dir); + + clear_nlink(inode); + inode->i_mtime = inode->i_atime = current_time(inode); + exfat_truncate_atime(&inode->i_atime); + exfat_unhash_inode(inode); + exfat_d_version_set(dentry, inode_query_iversion(dir)); +unlock: + mutex_unlock(&EXFAT_SB(sb)->s_lock); + return err; +} + +static int exfat_mkdir(struct user_namespace *mnt_userns, struct inode *dir, + struct dentry *dentry, umode_t mode) +{ + struct super_block *sb = dir->i_sb; + struct inode *inode; + struct exfat_dir_entry info; + struct exfat_chain cdir; + loff_t i_pos; + int err; + + mutex_lock(&EXFAT_SB(sb)->s_lock); + exfat_set_volume_dirty(sb); + err = exfat_add_entry(dir, dentry->d_name.name, &cdir, TYPE_DIR, + &info); + if (err) + goto unlock; + + inode_inc_iversion(dir); + dir->i_ctime = dir->i_mtime = current_time(dir); + if (IS_DIRSYNC(dir)) + exfat_sync_inode(dir); + else + mark_inode_dirty(dir); + inc_nlink(dir); + + i_pos = exfat_make_i_pos(&info); + inode = exfat_build_inode(sb, &info, i_pos); + err = PTR_ERR_OR_ZERO(inode); + if (err) + goto unlock; + + inode_inc_iversion(inode); + inode->i_mtime = inode->i_atime = inode->i_ctime = + EXFAT_I(inode)->i_crtime = current_time(inode); + exfat_truncate_atime(&inode->i_atime); + /* timestamp is already written, so mark_inode_dirty() is unneeded. */ + + d_instantiate(dentry, inode); + +unlock: + mutex_unlock(&EXFAT_SB(sb)->s_lock); + return err; +} + +static int exfat_check_dir_empty(struct super_block *sb, + struct exfat_chain *p_dir) +{ + int i, dentries_per_clu; + unsigned int type; + struct exfat_chain clu; + struct exfat_dentry *ep; + struct exfat_sb_info *sbi = EXFAT_SB(sb); + struct buffer_head *bh; + + dentries_per_clu = sbi->dentries_per_clu; + + exfat_chain_dup(&clu, p_dir); + + while (clu.dir != EXFAT_EOF_CLUSTER) { + for (i = 0; i < dentries_per_clu; i++) { + ep = exfat_get_dentry(sb, &clu, i, &bh); + if (!ep) + return -EIO; + type = exfat_get_entry_type(ep); + brelse(bh); + if (type == TYPE_UNUSED) + return 0; + + if (type != TYPE_FILE && type != TYPE_DIR) + continue; + + return -ENOTEMPTY; + } + + if (clu.flags == ALLOC_NO_FAT_CHAIN) { + if (--clu.size > 0) + clu.dir++; + else + clu.dir = EXFAT_EOF_CLUSTER; + } else { + if (exfat_get_next_cluster(sb, &(clu.dir))) + return -EIO; + } + } + + return 0; +} + +static int exfat_rmdir(struct inode *dir, struct dentry *dentry) +{ + struct inode *inode = dentry->d_inode; + struct exfat_dentry *ep; + struct exfat_chain cdir, clu_to_free; + struct super_block *sb = inode->i_sb; + struct exfat_sb_info *sbi = EXFAT_SB(sb); + struct exfat_inode_info *ei = EXFAT_I(inode); + struct buffer_head *bh; + int num_entries, entry, err; + + mutex_lock(&EXFAT_SB(inode->i_sb)->s_lock); + + exfat_chain_dup(&cdir, &ei->dir); + entry = ei->entry; + + if (ei->dir.dir == DIR_DELETED) { + exfat_err(sb, "abnormal access to deleted dentry"); + err = -ENOENT; + goto unlock; + } + + exfat_chain_set(&clu_to_free, ei->start_clu, + EXFAT_B_TO_CLU_ROUND_UP(i_size_read(inode), sbi), ei->flags); + + err = exfat_check_dir_empty(sb, &clu_to_free); + if (err) { + if (err == -EIO) + exfat_err(sb, "failed to exfat_check_dir_empty : err(%d)", + err); + goto unlock; + } + + ep = exfat_get_dentry(sb, &cdir, entry, &bh); + if (!ep) { + err = -EIO; + goto unlock; + } + + num_entries = exfat_count_ext_entries(sb, &cdir, entry, ep); + if (num_entries < 0) { + err = -EIO; + brelse(bh); + goto unlock; + } + num_entries++; + brelse(bh); + + exfat_set_volume_dirty(sb); + err = exfat_remove_entries(dir, &cdir, entry, 0, num_entries); + if (err) { + exfat_err(sb, "failed to exfat_remove_entries : err(%d)", err); + goto unlock; + } + ei->dir.dir = DIR_DELETED; + + inode_inc_iversion(dir); + dir->i_mtime = dir->i_atime = current_time(dir); + exfat_truncate_atime(&dir->i_atime); + if (IS_DIRSYNC(dir)) + exfat_sync_inode(dir); + else + mark_inode_dirty(dir); + drop_nlink(dir); + + clear_nlink(inode); + inode->i_mtime = inode->i_atime = current_time(inode); + exfat_truncate_atime(&inode->i_atime); + exfat_unhash_inode(inode); + exfat_d_version_set(dentry, inode_query_iversion(dir)); +unlock: + mutex_unlock(&EXFAT_SB(inode->i_sb)->s_lock); + return err; +} + +static int exfat_rename_file(struct inode *inode, struct exfat_chain *p_dir, + int oldentry, struct exfat_uni_name *p_uniname, + struct exfat_inode_info *ei) +{ + int ret, num_old_entries, num_new_entries; + struct exfat_dentry *epold, *epnew; + struct super_block *sb = inode->i_sb; + struct buffer_head *new_bh, *old_bh; + int sync = IS_DIRSYNC(inode); + + epold = exfat_get_dentry(sb, p_dir, oldentry, &old_bh); + if (!epold) + return -EIO; + + num_old_entries = exfat_count_ext_entries(sb, p_dir, oldentry, epold); + if (num_old_entries < 0) + return -EIO; + num_old_entries++; + + num_new_entries = exfat_calc_num_entries(p_uniname); + if (num_new_entries < 0) + return num_new_entries; + + if (num_old_entries < num_new_entries) { + int newentry; + + newentry = + exfat_find_empty_entry(inode, p_dir, num_new_entries); + if (newentry < 0) + return newentry; /* -EIO or -ENOSPC */ + + epnew = exfat_get_dentry(sb, p_dir, newentry, &new_bh); + if (!epnew) + return -EIO; + + *epnew = *epold; + if (exfat_get_entry_type(epnew) == TYPE_FILE) { + epnew->dentry.file.attr |= cpu_to_le16(ATTR_ARCHIVE); + ei->attr |= ATTR_ARCHIVE; + } + exfat_update_bh(new_bh, sync); + brelse(old_bh); + brelse(new_bh); + + epold = exfat_get_dentry(sb, p_dir, oldentry + 1, &old_bh); + if (!epold) + return -EIO; + epnew = exfat_get_dentry(sb, p_dir, newentry + 1, &new_bh); + if (!epnew) { + brelse(old_bh); + return -EIO; + } + + *epnew = *epold; + exfat_update_bh(new_bh, sync); + brelse(old_bh); + brelse(new_bh); + + ret = exfat_init_ext_entry(inode, p_dir, newentry, + num_new_entries, p_uniname); + if (ret) + return ret; + + exfat_remove_entries(inode, p_dir, oldentry, 0, + num_old_entries); + ei->dir = *p_dir; + ei->entry = newentry; + } else { + if (exfat_get_entry_type(epold) == TYPE_FILE) { + epold->dentry.file.attr |= cpu_to_le16(ATTR_ARCHIVE); + ei->attr |= ATTR_ARCHIVE; + } + exfat_update_bh(old_bh, sync); + brelse(old_bh); + ret = exfat_init_ext_entry(inode, p_dir, oldentry, + num_new_entries, p_uniname); + if (ret) + return ret; + + exfat_remove_entries(inode, p_dir, oldentry, num_new_entries, + num_old_entries); + } + return 0; +} + +static int exfat_move_file(struct inode *inode, struct exfat_chain *p_olddir, + int oldentry, struct exfat_chain *p_newdir, + struct exfat_uni_name *p_uniname, struct exfat_inode_info *ei) +{ + int ret, newentry, num_new_entries, num_old_entries; + struct exfat_dentry *epmov, *epnew; + struct super_block *sb = inode->i_sb; + struct buffer_head *mov_bh, *new_bh; + + epmov = exfat_get_dentry(sb, p_olddir, oldentry, &mov_bh); + if (!epmov) + return -EIO; + + num_old_entries = exfat_count_ext_entries(sb, p_olddir, oldentry, + epmov); + if (num_old_entries < 0) + return -EIO; + num_old_entries++; + + num_new_entries = exfat_calc_num_entries(p_uniname); + if (num_new_entries < 0) + return num_new_entries; + + newentry = exfat_find_empty_entry(inode, p_newdir, num_new_entries); + if (newentry < 0) + return newentry; /* -EIO or -ENOSPC */ + + epnew = exfat_get_dentry(sb, p_newdir, newentry, &new_bh); + if (!epnew) + return -EIO; + + *epnew = *epmov; + if (exfat_get_entry_type(epnew) == TYPE_FILE) { + epnew->dentry.file.attr |= cpu_to_le16(ATTR_ARCHIVE); + ei->attr |= ATTR_ARCHIVE; + } + exfat_update_bh(new_bh, IS_DIRSYNC(inode)); + brelse(mov_bh); + brelse(new_bh); + + epmov = exfat_get_dentry(sb, p_olddir, oldentry + 1, &mov_bh); + if (!epmov) + return -EIO; + epnew = exfat_get_dentry(sb, p_newdir, newentry + 1, &new_bh); + if (!epnew) { + brelse(mov_bh); + return -EIO; + } + + *epnew = *epmov; + exfat_update_bh(new_bh, IS_DIRSYNC(inode)); + brelse(mov_bh); + brelse(new_bh); + + ret = exfat_init_ext_entry(inode, p_newdir, newentry, num_new_entries, + p_uniname); + if (ret) + return ret; + + exfat_remove_entries(inode, p_olddir, oldentry, 0, num_old_entries); + + exfat_chain_set(&ei->dir, p_newdir->dir, p_newdir->size, + p_newdir->flags); + + ei->entry = newentry; + return 0; +} + +/* rename or move a old file into a new file */ +static int __exfat_rename(struct inode *old_parent_inode, + struct exfat_inode_info *ei, struct inode *new_parent_inode, + struct dentry *new_dentry) +{ + int ret; + int dentry; + struct exfat_chain olddir, newdir; + struct exfat_chain *p_dir = NULL; + struct exfat_uni_name uni_name; + struct exfat_dentry *ep; + struct super_block *sb = old_parent_inode->i_sb; + struct exfat_sb_info *sbi = EXFAT_SB(sb); + const unsigned char *new_path = new_dentry->d_name.name; + struct inode *new_inode = new_dentry->d_inode; + int num_entries; + struct exfat_inode_info *new_ei = NULL; + unsigned int new_entry_type = TYPE_UNUSED; + int new_entry = 0; + struct buffer_head *old_bh, *new_bh = NULL; + + /* check the validity of pointer parameters */ + if (new_path == NULL || strlen(new_path) == 0) + return -EINVAL; + + if (ei->dir.dir == DIR_DELETED) { + exfat_err(sb, "abnormal access to deleted source dentry"); + return -ENOENT; + } + + exfat_chain_set(&olddir, EXFAT_I(old_parent_inode)->start_clu, + EXFAT_B_TO_CLU_ROUND_UP(i_size_read(old_parent_inode), sbi), + EXFAT_I(old_parent_inode)->flags); + dentry = ei->entry; + + ep = exfat_get_dentry(sb, &olddir, dentry, &old_bh); + if (!ep) { + ret = -EIO; + goto out; + } + brelse(old_bh); + + /* check whether new dir is existing directory and empty */ + if (new_inode) { + ret = -EIO; + new_ei = EXFAT_I(new_inode); + + if (new_ei->dir.dir == DIR_DELETED) { + exfat_err(sb, "abnormal access to deleted target dentry"); + goto out; + } + + p_dir = &(new_ei->dir); + new_entry = new_ei->entry; + ep = exfat_get_dentry(sb, p_dir, new_entry, &new_bh); + if (!ep) + goto out; + + new_entry_type = exfat_get_entry_type(ep); + brelse(new_bh); + + /* if new_inode exists, update ei */ + if (new_entry_type == TYPE_DIR) { + struct exfat_chain new_clu; + + new_clu.dir = new_ei->start_clu; + new_clu.size = + EXFAT_B_TO_CLU_ROUND_UP(i_size_read(new_inode), + sbi); + new_clu.flags = new_ei->flags; + + ret = exfat_check_dir_empty(sb, &new_clu); + if (ret) + goto out; + } + } + + /* check the validity of directory name in the given new pathname */ + ret = exfat_resolve_path(new_parent_inode, new_path, &newdir, + &uni_name); + if (ret) + goto out; + + exfat_set_volume_dirty(sb); + + if (olddir.dir == newdir.dir) + ret = exfat_rename_file(new_parent_inode, &olddir, dentry, + &uni_name, ei); + else + ret = exfat_move_file(new_parent_inode, &olddir, dentry, + &newdir, &uni_name, ei); + + if (!ret && new_inode) { + /* delete entries of new_dir */ + ep = exfat_get_dentry(sb, p_dir, new_entry, &new_bh); + if (!ep) { + ret = -EIO; + goto del_out; + } + + num_entries = exfat_count_ext_entries(sb, p_dir, new_entry, ep); + if (num_entries < 0) { + ret = -EIO; + goto del_out; + } + brelse(new_bh); + + if (exfat_remove_entries(new_inode, p_dir, new_entry, 0, + num_entries + 1)) { + ret = -EIO; + goto del_out; + } + + /* Free the clusters if new_inode is a dir(as if exfat_rmdir) */ + if (new_entry_type == TYPE_DIR) { + /* new_ei, new_clu_to_free */ + struct exfat_chain new_clu_to_free; + + exfat_chain_set(&new_clu_to_free, new_ei->start_clu, + EXFAT_B_TO_CLU_ROUND_UP(i_size_read(new_inode), + sbi), new_ei->flags); + + if (exfat_free_cluster(new_inode, &new_clu_to_free)) { + /* just set I/O error only */ + ret = -EIO; + } + + i_size_write(new_inode, 0); + new_ei->start_clu = EXFAT_EOF_CLUSTER; + new_ei->flags = ALLOC_NO_FAT_CHAIN; + } +del_out: + /* Update new_inode ei + * Prevent syncing removed new_inode + * (new_ei is already initialized above code ("if (new_inode)") + */ + new_ei->dir.dir = DIR_DELETED; + } +out: + return ret; +} + +static int exfat_rename(struct user_namespace *mnt_userns, + struct inode *old_dir, struct dentry *old_dentry, + struct inode *new_dir, struct dentry *new_dentry, + unsigned int flags) +{ + struct inode *old_inode, *new_inode; + struct super_block *sb = old_dir->i_sb; + loff_t i_pos; + int err; + + /* + * The VFS already checks for existence, so for local filesystems + * the RENAME_NOREPLACE implementation is equivalent to plain rename. + * Don't support any other flags + */ + if (flags & ~RENAME_NOREPLACE) + return -EINVAL; + + mutex_lock(&EXFAT_SB(sb)->s_lock); + old_inode = old_dentry->d_inode; + new_inode = new_dentry->d_inode; + + err = __exfat_rename(old_dir, EXFAT_I(old_inode), new_dir, new_dentry); + if (err) + goto unlock; + + inode_inc_iversion(new_dir); + new_dir->i_ctime = new_dir->i_mtime = new_dir->i_atime = + EXFAT_I(new_dir)->i_crtime = current_time(new_dir); + exfat_truncate_atime(&new_dir->i_atime); + if (IS_DIRSYNC(new_dir)) + exfat_sync_inode(new_dir); + else + mark_inode_dirty(new_dir); + + i_pos = ((loff_t)EXFAT_I(old_inode)->dir.dir << 32) | + (EXFAT_I(old_inode)->entry & 0xffffffff); + exfat_unhash_inode(old_inode); + exfat_hash_inode(old_inode, i_pos); + if (IS_DIRSYNC(new_dir)) + exfat_sync_inode(old_inode); + else + mark_inode_dirty(old_inode); + + if (S_ISDIR(old_inode->i_mode) && old_dir != new_dir) { + drop_nlink(old_dir); + if (!new_inode) + inc_nlink(new_dir); + } + + inode_inc_iversion(old_dir); + old_dir->i_ctime = old_dir->i_mtime = current_time(old_dir); + if (IS_DIRSYNC(old_dir)) + exfat_sync_inode(old_dir); + else + mark_inode_dirty(old_dir); + + if (new_inode) { + exfat_unhash_inode(new_inode); + + /* skip drop_nlink if new_inode already has been dropped */ + if (new_inode->i_nlink) { + drop_nlink(new_inode); + if (S_ISDIR(new_inode->i_mode)) + drop_nlink(new_inode); + } else { + exfat_warn(sb, "abnormal access to an inode dropped"); + WARN_ON(new_inode->i_nlink == 0); + } + new_inode->i_ctime = EXFAT_I(new_inode)->i_crtime = + current_time(new_inode); + } + +unlock: + mutex_unlock(&EXFAT_SB(sb)->s_lock); + return err; +} + +const struct inode_operations exfat_dir_inode_operations = { + .create = exfat_create, + .lookup = exfat_lookup, + .unlink = exfat_unlink, + .mkdir = exfat_mkdir, + .rmdir = exfat_rmdir, + .rename = exfat_rename, + .setattr = exfat_setattr, + .getattr = exfat_getattr, +}; 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