diff options
Diffstat (limited to 'fs/affs/namei.c')
-rw-r--r-- | fs/affs/namei.c | 443 |
1 files changed, 443 insertions, 0 deletions
diff --git a/fs/affs/namei.c b/fs/affs/namei.c new file mode 100644 index 000000000000..d4c2d636c479 --- /dev/null +++ b/fs/affs/namei.c @@ -0,0 +1,443 @@ +/* + * 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(struct dentry *, struct qstr *); +static int affs_compare_dentry(struct dentry *, struct qstr *, struct qstr *); +static int affs_intl_toupper(int ch); +static int affs_intl_hash_dentry(struct dentry *, struct qstr *); +static int affs_intl_compare_dentry(struct dentry *, struct qstr *, struct qstr *); + +struct dentry_operations affs_dentry_operations = { + .d_hash = affs_hash_dentry, + .d_compare = affs_compare_dentry, +}; + +static 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_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 dentry *dentry, struct qstr *qstr, toupper_t toupper) +{ + const u8 *name = qstr->name; + unsigned long hash; + int i; + + i = affs_check_name(qstr->name,qstr->len); + if (i) + return i; + + hash = init_name_hash(); + i = min(qstr->len, 30u); + for (; i > 0; name++, i--) + hash = partial_name_hash(toupper(*name), hash); + qstr->hash = end_name_hash(hash); + + return 0; +} + +static int +affs_hash_dentry(struct dentry *dentry, struct qstr *qstr) +{ + return __affs_hash_dentry(dentry, qstr, affs_toupper); +} +static int +affs_intl_hash_dentry(struct dentry *dentry, struct qstr *qstr) +{ + return __affs_hash_dentry(dentry, qstr, affs_intl_toupper); +} + +static inline int +__affs_compare_dentry(struct dentry *dentry, struct qstr *a, struct qstr *b, toupper_t toupper) +{ + const u8 *aname = a->name; + const u8 *bname = b->name; + int len; + + /* 'a' is the qstr of an already existing dentry, so the name + * must be valid. 'b' must be validated first. + */ + + if (affs_check_name(b->name,b->len)) + return 1; + + /* If the names are longer than the allowed 30 chars, + * the excess is ignored, so their length may differ. + */ + len = a->len; + if (len >= 30) { + if (b->len < 30) + return 1; + len = 30; + } else if (len != b->len) + return 1; + + for (; len > 0; len--) + if (toupper(*aname++) != toupper(*bname++)) + return 1; + + return 0; +} + +static int +affs_compare_dentry(struct dentry *dentry, struct qstr *a, struct qstr *b) +{ + return __affs_compare_dentry(dentry, a, b, affs_toupper); +} +static int +affs_intl_compare_dentry(struct dentry *dentry, struct qstr *a, struct qstr *b) +{ + return __affs_compare_dentry(dentry, a, b, affs_intl_toupper); +} + +/* + * 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 >= 30) { + if (*name2 < 30) + return 0; + len = 30; + } 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); + int hash; + + hash = len = min(len, 30u); + 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("AFFS: find_entry(\"%.*s\")\n", (int)dentry->d_name.len, dentry->d_name.name); + + 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, struct nameidata *nd) +{ + struct super_block *sb = dir->i_sb; + struct buffer_head *bh; + struct inode *inode = NULL; + + pr_debug("AFFS: lookup(\"%.*s\")\n",(int)dentry->d_name.len,dentry->d_name.name); + + affs_lock_dir(dir); + bh = affs_find_entry(dir, dentry); + affs_unlock_dir(dir); + if (IS_ERR(bh)) { + return ERR_PTR(PTR_ERR(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 = iget(sb, ino); + if (!inode) { + return ERR_PTR(-EACCES); + } + } + dentry->d_op = AFFS_SB(sb)->s_flags & SF_INTL ? &affs_intl_dentry_operations : &affs_dentry_operations; + d_add(dentry, inode); + return NULL; +} + +int +affs_unlink(struct inode *dir, struct dentry *dentry) +{ + pr_debug("AFFS: unlink(dir=%d, \"%.*s\")\n", (u32)dir->i_ino, + (int)dentry->d_name.len, dentry->d_name.name); + + return affs_remove_header(dentry); +} + +int +affs_create(struct inode *dir, struct dentry *dentry, int mode, struct nameidata *nd) +{ + struct super_block *sb = dir->i_sb; + struct inode *inode; + int error; + + pr_debug("AFFS: create(%lu,\"%.*s\",0%o)\n",dir->i_ino,(int)dentry->d_name.len, + dentry->d_name.name,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_SB(sb)->s_flags & SF_OFS) ? &affs_aops_ofs : &affs_aops; + error = affs_add_entry(dir, inode, dentry, ST_FILE); + if (error) { + inode->i_nlink = 0; + iput(inode); + return error; + } + return 0; +} + +int +affs_mkdir(struct inode *dir, struct dentry *dentry, int mode) +{ + struct inode *inode; + int error; + + pr_debug("AFFS: mkdir(%lu,\"%.*s\",0%o)\n",dir->i_ino, + (int)dentry->d_name.len,dentry->d_name.name,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) { + inode->i_nlink = 0; + mark_inode_dirty(inode); + iput(inode); + return error; + } + return 0; +} + +int +affs_rmdir(struct inode *dir, struct dentry *dentry) +{ + pr_debug("AFFS: rmdir(dir=%u, \"%.*s\")\n", (u32)dir->i_ino, + (int)dentry->d_name.len, dentry->d_name.name); + + 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("AFFS: symlink(%lu,\"%.*s\" -> \"%s\")\n",dir->i_ino, + (int)dentry->d_name.len,dentry->d_name.name,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 == '/') { + while (*symname == '/') + symname++; + while (AFFS_SB(sb)->s_volume[i]) /* Cannot overflow */ + *p++ = AFFS_SB(sb)->s_volume[i++]; + } + 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: + inode->i_nlink = 0; + mark_inode_dirty(inode); + iput(inode); + return error; +} + +int +affs_link(struct dentry *old_dentry, struct inode *dir, struct dentry *dentry) +{ + struct inode *inode = old_dentry->d_inode; + + pr_debug("AFFS: link(%u, %u, \"%.*s\")\n", (u32)inode->i_ino, (u32)dir->i_ino, + (int)dentry->d_name.len,dentry->d_name.name); + + 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("AFFS: rename(old=%u,\"%*s\" to new=%u,\"%*s\")\n", + (u32)old_dir->i_ino, (int)old_dentry->d_name.len, old_dentry->d_name.name, + (u32)new_dir->i_ino, (int)new_dentry->d_name.len, new_dentry->d_name.name); + + retval = affs_check_name(new_dentry->d_name.name,new_dentry->d_name.len); + if (retval) + return retval; + + /* Unlink destination if it already exists */ + if (new_dentry->d_inode) { + retval = affs_remove_header(new_dentry); + if (retval) + return retval; + } + + retval = -EIO; + bh = affs_bread(sb, old_dentry->d_inode->i_ino); + if (!bh) + goto done; + + /* 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; +} |