From 57f0f512b273f60d52568b8c6b77e17f5636edc0 Mon Sep 17 00:00:00 2001 From: André Fabian Silva Delgado Date: Wed, 5 Aug 2015 17:04:01 -0300 Subject: Initial import --- fs/affs/namei.c | 462 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 462 insertions(+) create mode 100644 fs/affs/namei.c (limited to 'fs/affs/namei.c') diff --git a/fs/affs/namei.c b/fs/affs/namei.c new file mode 100644 index 000000000..181e05b46 --- /dev/null +++ b/fs/affs/namei.c @@ -0,0 +1,462 @@ +/* + * linux/fs/affs/namei.c + * + * (c) 1996 Hans-Joachim Widmaier - Rewritten + * + * (C) 1993 Ray Burr - Modified for Amiga FFS filesystem. + * + * (C) 1991 Linus Torvalds - minix filesystem + */ + +#include "affs.h" + +typedef int (*toupper_t)(int); + +static int affs_toupper(int ch); +static int affs_hash_dentry(const struct dentry *, struct qstr *); +static int affs_compare_dentry(const struct dentry *parent, const struct dentry *dentry, + unsigned int len, const char *str, const struct qstr *name); +static int affs_intl_toupper(int ch); +static int affs_intl_hash_dentry(const struct dentry *, struct qstr *); +static int affs_intl_compare_dentry(const struct dentry *parent, const struct dentry *dentry, + unsigned int len, const char *str, const struct qstr *name); + +const struct dentry_operations affs_dentry_operations = { + .d_hash = affs_hash_dentry, + .d_compare = affs_compare_dentry, +}; + +const struct dentry_operations affs_intl_dentry_operations = { + .d_hash = affs_intl_hash_dentry, + .d_compare = affs_intl_compare_dentry, +}; + + +/* Simple toupper() for DOS\1 */ + +static int +affs_toupper(int ch) +{ + return ch >= 'a' && ch <= 'z' ? ch -= ('a' - 'A') : ch; +} + +/* International toupper() for DOS\3 ("international") */ + +static int +affs_intl_toupper(int ch) +{ + return (ch >= 'a' && ch <= 'z') || (ch >= 0xE0 + && ch <= 0xFE && ch != 0xF7) ? + ch - ('a' - 'A') : ch; +} + +static inline toupper_t +affs_get_toupper(struct super_block *sb) +{ + return affs_test_opt(AFFS_SB(sb)->s_flags, SF_INTL) ? + affs_intl_toupper : affs_toupper; +} + +/* + * Note: the dentry argument is the parent dentry. + */ +static inline int +__affs_hash_dentry(struct qstr *qstr, toupper_t toupper, bool notruncate) +{ + const u8 *name = qstr->name; + unsigned long hash; + int retval; + u32 len; + + retval = affs_check_name(qstr->name, qstr->len, notruncate); + if (retval) + return retval; + + hash = init_name_hash(); + len = min(qstr->len, AFFSNAMEMAX); + for (; len > 0; name++, len--) + hash = partial_name_hash(toupper(*name), hash); + qstr->hash = end_name_hash(hash); + + return 0; +} + +static int +affs_hash_dentry(const struct dentry *dentry, struct qstr *qstr) +{ + return __affs_hash_dentry(qstr, affs_toupper, + affs_nofilenametruncate(dentry)); + +} + +static int +affs_intl_hash_dentry(const struct dentry *dentry, struct qstr *qstr) +{ + return __affs_hash_dentry(qstr, affs_intl_toupper, + affs_nofilenametruncate(dentry)); + +} + +static inline int __affs_compare_dentry(unsigned int len, + const char *str, const struct qstr *name, toupper_t toupper, + bool notruncate) +{ + const u8 *aname = str; + const u8 *bname = name->name; + + /* + * 'str' is the name of an already existing dentry, so the name + * must be valid. 'name' must be validated first. + */ + + if (affs_check_name(name->name, name->len, notruncate)) + return 1; + + /* + * If the names are longer than the allowed 30 chars, + * the excess is ignored, so their length may differ. + */ + if (len >= AFFSNAMEMAX) { + if (name->len < AFFSNAMEMAX) + return 1; + len = AFFSNAMEMAX; + } else if (len != name->len) + return 1; + + for (; len > 0; len--) + if (toupper(*aname++) != toupper(*bname++)) + return 1; + + return 0; +} + +static int +affs_compare_dentry(const struct dentry *parent, const struct dentry *dentry, + unsigned int len, const char *str, const struct qstr *name) +{ + + return __affs_compare_dentry(len, str, name, affs_toupper, + affs_nofilenametruncate(parent)); +} + +static int +affs_intl_compare_dentry(const struct dentry *parent, const struct dentry *dentry, + unsigned int len, const char *str, const struct qstr *name) +{ + return __affs_compare_dentry(len, str, name, affs_intl_toupper, + affs_nofilenametruncate(parent)); + +} + +/* + * NOTE! unlike strncmp, affs_match returns 1 for success, 0 for failure. + */ + +static inline int +affs_match(struct dentry *dentry, const u8 *name2, toupper_t toupper) +{ + const u8 *name = dentry->d_name.name; + int len = dentry->d_name.len; + + if (len >= AFFSNAMEMAX) { + if (*name2 < AFFSNAMEMAX) + return 0; + len = AFFSNAMEMAX; + } else if (len != *name2) + return 0; + + for (name2++; len > 0; len--) + if (toupper(*name++) != toupper(*name2++)) + return 0; + return 1; +} + +int +affs_hash_name(struct super_block *sb, const u8 *name, unsigned int len) +{ + toupper_t toupper = affs_get_toupper(sb); + u32 hash; + + hash = len = min(len, AFFSNAMEMAX); + for (; len > 0; len--) + hash = (hash * 13 + toupper(*name++)) & 0x7ff; + + return hash % AFFS_SB(sb)->s_hashsize; +} + +static struct buffer_head * +affs_find_entry(struct inode *dir, struct dentry *dentry) +{ + struct super_block *sb = dir->i_sb; + struct buffer_head *bh; + toupper_t toupper = affs_get_toupper(sb); + u32 key; + + pr_debug("%s(\"%pd\")\n", __func__, dentry); + + bh = affs_bread(sb, dir->i_ino); + if (!bh) + return ERR_PTR(-EIO); + + key = be32_to_cpu(AFFS_HEAD(bh)->table[affs_hash_name(sb, dentry->d_name.name, dentry->d_name.len)]); + + for (;;) { + affs_brelse(bh); + if (key == 0) + return NULL; + bh = affs_bread(sb, key); + if (!bh) + return ERR_PTR(-EIO); + if (affs_match(dentry, AFFS_TAIL(sb, bh)->name, toupper)) + return bh; + key = be32_to_cpu(AFFS_TAIL(sb, bh)->hash_chain); + } +} + +struct dentry * +affs_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags) +{ + struct super_block *sb = dir->i_sb; + struct buffer_head *bh; + struct inode *inode = NULL; + + pr_debug("%s(\"%pd\")\n", __func__, dentry); + + affs_lock_dir(dir); + bh = affs_find_entry(dir, dentry); + affs_unlock_dir(dir); + if (IS_ERR(bh)) + return ERR_CAST(bh); + if (bh) { + u32 ino = bh->b_blocknr; + + /* store the real header ino in d_fsdata for faster lookups */ + dentry->d_fsdata = (void *)(long)ino; + switch (be32_to_cpu(AFFS_TAIL(sb, bh)->stype)) { + //link to dirs disabled + //case ST_LINKDIR: + case ST_LINKFILE: + ino = be32_to_cpu(AFFS_TAIL(sb, bh)->original); + } + affs_brelse(bh); + inode = affs_iget(sb, ino); + if (IS_ERR(inode)) + return ERR_CAST(inode); + } + d_add(dentry, inode); + return NULL; +} + +int +affs_unlink(struct inode *dir, struct dentry *dentry) +{ + pr_debug("%s(dir=%lu, %lu \"%pd\")\n", __func__, dir->i_ino, + d_inode(dentry)->i_ino, dentry); + + return affs_remove_header(dentry); +} + +int +affs_create(struct inode *dir, struct dentry *dentry, umode_t mode, bool excl) +{ + struct super_block *sb = dir->i_sb; + struct inode *inode; + int error; + + pr_debug("%s(%lu,\"%pd\",0%ho)\n", + __func__, dir->i_ino, dentry, mode); + + inode = affs_new_inode(dir); + if (!inode) + return -ENOSPC; + + inode->i_mode = mode; + mode_to_prot(inode); + mark_inode_dirty(inode); + + inode->i_op = &affs_file_inode_operations; + inode->i_fop = &affs_file_operations; + inode->i_mapping->a_ops = affs_test_opt(AFFS_SB(sb)->s_flags, SF_OFS) ? + &affs_aops_ofs : &affs_aops; + error = affs_add_entry(dir, inode, dentry, ST_FILE); + if (error) { + clear_nlink(inode); + iput(inode); + return error; + } + return 0; +} + +int +affs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode) +{ + struct inode *inode; + int error; + + pr_debug("%s(%lu,\"%pd\",0%ho)\n", + __func__, dir->i_ino, dentry, mode); + + inode = affs_new_inode(dir); + if (!inode) + return -ENOSPC; + + inode->i_mode = S_IFDIR | mode; + mode_to_prot(inode); + + inode->i_op = &affs_dir_inode_operations; + inode->i_fop = &affs_dir_operations; + + error = affs_add_entry(dir, inode, dentry, ST_USERDIR); + if (error) { + clear_nlink(inode); + mark_inode_dirty(inode); + iput(inode); + return error; + } + return 0; +} + +int +affs_rmdir(struct inode *dir, struct dentry *dentry) +{ + pr_debug("%s(dir=%lu, %lu \"%pd\")\n", __func__, dir->i_ino, + d_inode(dentry)->i_ino, dentry); + + return affs_remove_header(dentry); +} + +int +affs_symlink(struct inode *dir, struct dentry *dentry, const char *symname) +{ + struct super_block *sb = dir->i_sb; + struct buffer_head *bh; + struct inode *inode; + char *p; + int i, maxlen, error; + char c, lc; + + pr_debug("%s(%lu,\"%pd\" -> \"%s\")\n", + __func__, dir->i_ino, dentry, symname); + + maxlen = AFFS_SB(sb)->s_hashsize * sizeof(u32) - 1; + inode = affs_new_inode(dir); + if (!inode) + return -ENOSPC; + + inode->i_op = &affs_symlink_inode_operations; + inode->i_data.a_ops = &affs_symlink_aops; + inode->i_mode = S_IFLNK | 0777; + mode_to_prot(inode); + + error = -EIO; + bh = affs_bread(sb, inode->i_ino); + if (!bh) + goto err; + i = 0; + p = (char *)AFFS_HEAD(bh)->table; + lc = '/'; + if (*symname == '/') { + struct affs_sb_info *sbi = AFFS_SB(sb); + while (*symname == '/') + symname++; + spin_lock(&sbi->symlink_lock); + while (sbi->s_volume[i]) /* Cannot overflow */ + *p++ = sbi->s_volume[i++]; + spin_unlock(&sbi->symlink_lock); + } + while (i < maxlen && (c = *symname++)) { + if (c == '.' && lc == '/' && *symname == '.' && symname[1] == '/') { + *p++ = '/'; + i++; + symname += 2; + lc = '/'; + } else if (c == '.' && lc == '/' && *symname == '/') { + symname++; + lc = '/'; + } else { + *p++ = c; + lc = c; + i++; + } + if (lc == '/') + while (*symname == '/') + symname++; + } + *p = 0; + mark_buffer_dirty_inode(bh, inode); + affs_brelse(bh); + mark_inode_dirty(inode); + + error = affs_add_entry(dir, inode, dentry, ST_SOFTLINK); + if (error) + goto err; + + return 0; + +err: + clear_nlink(inode); + mark_inode_dirty(inode); + iput(inode); + return error; +} + +int +affs_link(struct dentry *old_dentry, struct inode *dir, struct dentry *dentry) +{ + struct inode *inode = d_inode(old_dentry); + + pr_debug("%s(%lu, %lu, \"%pd\")\n", __func__, inode->i_ino, dir->i_ino, + dentry); + + return affs_add_entry(dir, inode, dentry, ST_LINKFILE); +} + +int +affs_rename(struct inode *old_dir, struct dentry *old_dentry, + struct inode *new_dir, struct dentry *new_dentry) +{ + struct super_block *sb = old_dir->i_sb; + struct buffer_head *bh = NULL; + int retval; + + pr_debug("%s(old=%lu,\"%pd\" to new=%lu,\"%pd\")\n", __func__, + old_dir->i_ino, old_dentry, new_dir->i_ino, new_dentry); + + retval = affs_check_name(new_dentry->d_name.name, + new_dentry->d_name.len, + affs_nofilenametruncate(old_dentry)); + + if (retval) + return retval; + + /* Unlink destination if it already exists */ + if (d_really_is_positive(new_dentry)) { + retval = affs_remove_header(new_dentry); + if (retval) + return retval; + } + + bh = affs_bread(sb, d_inode(old_dentry)->i_ino); + if (!bh) + return -EIO; + + /* Remove header from its parent directory. */ + affs_lock_dir(old_dir); + retval = affs_remove_hash(old_dir, bh); + affs_unlock_dir(old_dir); + if (retval) + goto done; + + /* And insert it into the new directory with the new name. */ + affs_copy_name(AFFS_TAIL(sb, bh)->name, new_dentry); + affs_fix_checksum(sb, bh); + affs_lock_dir(new_dir); + retval = affs_insert_hash(new_dir, bh); + affs_unlock_dir(new_dir); + /* TODO: move it back to old_dir, if error? */ + +done: + mark_buffer_dirty_inode(bh, retval ? old_dir : new_dir); + affs_brelse(bh); + return retval; +} -- cgit v1.2.3-54-g00ecf