diff options
Diffstat (limited to 'fs/minix/namei.c')
| -rw-r--r-- | fs/minix/namei.c | 317 |
1 files changed, 317 insertions, 0 deletions
diff --git a/fs/minix/namei.c b/fs/minix/namei.c new file mode 100644 index 0000000..b25bca5 --- /dev/null +++ b/fs/minix/namei.c @@ -0,0 +1,317 @@ +/* + * linux/fs/minix/namei.c + * + * Copyright (C) 1991, 1992 Linus Torvalds + */ + +#include "minix.h" + +static inline void inc_count(struct inode *inode) +{ + inode->i_nlink++; + mark_inode_dirty(inode); +} + +static inline void dec_count(struct inode *inode) +{ + inode->i_nlink--; + mark_inode_dirty(inode); +} + +static int add_nondir(struct dentry *dentry, struct inode *inode) +{ + int err = minix_add_link(dentry, inode); + if (!err) { + d_instantiate(dentry, inode); + return 0; + } + dec_count(inode); + iput(inode); + return err; +} + +static int minix_hash(struct dentry *dentry, struct qstr *qstr) +{ + unsigned long hash; + int i; + const unsigned char *name; + + i = minix_sb(dentry->d_inode->i_sb)->s_namelen; + if (i >= qstr->len) + return 0; + /* Truncate the name in place, avoids having to define a compare + function. */ + qstr->len = i; + name = qstr->name; + hash = init_name_hash(); + while (i--) + hash = partial_name_hash(*name++, hash); + qstr->hash = end_name_hash(hash); + return 0; +} + +struct dentry_operations minix_dentry_operations = { + .d_hash = minix_hash, +}; + +static struct dentry *minix_lookup(struct inode * dir, struct dentry *dentry, struct nameidata *nd) +{ + struct inode * inode = NULL; + ino_t ino; + + dentry->d_op = dir->i_sb->s_root->d_op; + + if (dentry->d_name.len > minix_sb(dir->i_sb)->s_namelen) + return ERR_PTR(-ENAMETOOLONG); + + ino = minix_inode_by_name(dentry); + if (ino) { + inode = iget(dir->i_sb, ino); + + if (!inode) + return ERR_PTR(-EACCES); + } + d_add(dentry, inode); + return NULL; +} + +static int minix_mknod(struct inode * dir, struct dentry *dentry, int mode, dev_t rdev) +{ + int error; + struct inode *inode; + + if (!old_valid_dev(rdev)) + return -EINVAL; + + inode = minix_new_inode(dir, &error); + + if (inode) { + inode->i_mode = mode; + minix_set_inode(inode, rdev); + mark_inode_dirty(inode); + error = add_nondir(dentry, inode); + } + return error; +} + +static int minix_create(struct inode * dir, struct dentry *dentry, int mode, + struct nameidata *nd) +{ + return minix_mknod(dir, dentry, mode, 0); +} + +static int minix_symlink(struct inode * dir, struct dentry *dentry, + const char * symname) +{ + int err = -ENAMETOOLONG; + int i = strlen(symname)+1; + struct inode * inode; + + if (i > dir->i_sb->s_blocksize) + goto out; + + inode = minix_new_inode(dir, &err); + if (!inode) + goto out; + + inode->i_mode = S_IFLNK | 0777; + minix_set_inode(inode, 0); + err = page_symlink(inode, symname, i); + if (err) + goto out_fail; + + err = add_nondir(dentry, inode); +out: + return err; + +out_fail: + dec_count(inode); + iput(inode); + goto out; +} + +static int minix_link(struct dentry * old_dentry, struct inode * dir, + struct dentry *dentry) +{ + struct inode *inode = old_dentry->d_inode; + + if (inode->i_nlink >= minix_sb(inode->i_sb)->s_link_max) + return -EMLINK; + + inode->i_ctime = CURRENT_TIME_SEC; + inc_count(inode); + atomic_inc(&inode->i_count); + return add_nondir(dentry, inode); +} + +static int minix_mkdir(struct inode * dir, struct dentry *dentry, int mode) +{ + struct inode * inode; + int err = -EMLINK; + + if (dir->i_nlink >= minix_sb(dir->i_sb)->s_link_max) + goto out; + + inc_count(dir); + + inode = minix_new_inode(dir, &err); + if (!inode) + goto out_dir; + + inode->i_mode = S_IFDIR | mode; + if (dir->i_mode & S_ISGID) + inode->i_mode |= S_ISGID; + minix_set_inode(inode, 0); + + inc_count(inode); + + err = minix_make_empty(inode, dir); + if (err) + goto out_fail; + + err = minix_add_link(dentry, inode); + if (err) + goto out_fail; + + d_instantiate(dentry, inode); +out: + return err; + +out_fail: + dec_count(inode); + dec_count(inode); + iput(inode); +out_dir: + dec_count(dir); + goto out; +} + +static int minix_unlink(struct inode * dir, struct dentry *dentry) +{ + int err = -ENOENT; + struct inode * inode = dentry->d_inode; + struct page * page; + struct minix_dir_entry * de; + + de = minix_find_entry(dentry, &page); + if (!de) + goto end_unlink; + + err = minix_delete_entry(de, page); + if (err) + goto end_unlink; + + inode->i_ctime = dir->i_ctime; + dec_count(inode); +end_unlink: + return err; +} + +static int minix_rmdir(struct inode * dir, struct dentry *dentry) +{ + struct inode * inode = dentry->d_inode; + int err = -ENOTEMPTY; + + if (minix_empty_dir(inode)) { + err = minix_unlink(dir, dentry); + if (!err) { + dec_count(dir); + dec_count(inode); + } + } + return err; +} + +static int minix_rename(struct inode * old_dir, struct dentry *old_dentry, + struct inode * new_dir, struct dentry *new_dentry) +{ + struct minix_sb_info * info = minix_sb(old_dir->i_sb); + struct inode * old_inode = old_dentry->d_inode; + struct inode * new_inode = new_dentry->d_inode; + struct page * dir_page = NULL; + struct minix_dir_entry * dir_de = NULL; + struct page * old_page; + struct minix_dir_entry * old_de; + int err = -ENOENT; + + old_de = minix_find_entry(old_dentry, &old_page); + if (!old_de) + goto out; + + if (S_ISDIR(old_inode->i_mode)) { + err = -EIO; + dir_de = minix_dotdot(old_inode, &dir_page); + if (!dir_de) + goto out_old; + } + + if (new_inode) { + struct page * new_page; + struct minix_dir_entry * new_de; + + err = -ENOTEMPTY; + if (dir_de && !minix_empty_dir(new_inode)) + goto out_dir; + + err = -ENOENT; + new_de = minix_find_entry(new_dentry, &new_page); + if (!new_de) + goto out_dir; + inc_count(old_inode); + minix_set_link(new_de, new_page, old_inode); + new_inode->i_ctime = CURRENT_TIME_SEC; + if (dir_de) + new_inode->i_nlink--; + dec_count(new_inode); + } else { + if (dir_de) { + err = -EMLINK; + if (new_dir->i_nlink >= info->s_link_max) + goto out_dir; + } + inc_count(old_inode); + err = minix_add_link(new_dentry, old_inode); + if (err) { + dec_count(old_inode); + goto out_dir; + } + if (dir_de) + inc_count(new_dir); + } + + minix_delete_entry(old_de, old_page); + dec_count(old_inode); + + if (dir_de) { + minix_set_link(dir_de, dir_page, new_dir); + dec_count(old_dir); + } + return 0; + +out_dir: + if (dir_de) { + kunmap(dir_page); + page_cache_release(dir_page); + } +out_old: + kunmap(old_page); + page_cache_release(old_page); +out: + return err; +} + +/* + * directories can handle most operations... + */ +struct inode_operations minix_dir_inode_operations = { + .create = minix_create, + .lookup = minix_lookup, + .link = minix_link, + .unlink = minix_unlink, + .symlink = minix_symlink, + .mkdir = minix_mkdir, + .rmdir = minix_rmdir, + .mknod = minix_mknod, + .rename = minix_rename, + .getattr = minix_getattr, +}; |
