namei.c

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/*
 *  linux/fs/hpfs/namei.c
 *
 *  Mikulas Patocka ([e-mail]), 1998-1999
 *
 *  adding & removing files & directories
 */

#include <linux/string.h>
#include "hpfs_fn.h"

int hpfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
{
	const char *name = dentry->d_name.name;
	unsigned len = dentry->d_name.len;
	struct quad_buffer_head qbh0;
	struct buffer_head *bh;
	struct hpfs_dirent *de;
	struct fnode *fnode;
	struct dnode *dnode;
	struct inode *result;
	fnode_secno fno;
	dnode_secno dno;
	int r;
	struct hpfs_dirent dee;
	int err;
	if ((err = hpfs_chk_name((char *)name, &len))) return err==-ENOENT ? -EINVAL : err;
	if (!(fnode = hpfs_alloc_fnode(dir->i_sb, dir->i_hpfs_dno, &fno, &bh))) goto bail;
	if (!(dnode = hpfs_alloc_dnode(dir->i_sb, fno, &dno, &qbh0, 1))) goto bail1;
	memset(&dee, 0, sizeof dee);
	dee.directory = 1;
	if (!(mode & 0222)) dee.read_only = 1;
	/*dee.archive = 0;*/
	dee.hidden = name[0] == '.';
	dee.fnode = fno;
	dee.creation_date = dee.write_date = dee.read_date = gmt_to_local(dir->i_sb, CURRENT_TIME);
	hpfs_lock_inode(dir);
	r = hpfs_add_dirent(dir, (char *)name, len, &dee, 0);
	if (r == 1) goto bail2;
	if (r == -1) {
		brelse(bh);
		hpfs_brelse4(&qbh0);
		hpfs_free_sectors(dir->i_sb, fno, 1);
		hpfs_free_dnode(dir->i_sb, dno);
		hpfs_unlock_inode(dir);
		return -EEXIST;
	}
	fnode->len = len;
	memcpy(fnode->name, name, len > 15 ? 15 : len);
	fnode->up = dir->i_ino;
	fnode->dirflag = 1;
	fnode->btree.n_free_nodes = 7;
	fnode->btree.n_used_nodes = 1;
	fnode->btree.first_free = 0x14;
	fnode->u.external[0].disk_secno = dno;
	fnode->u.external[0].file_secno = -1;
	dnode->root_dnode = 1;
	dnode->up = fno;
	de = hpfs_add_de(dir->i_sb, dnode, "\001\001", 2, 0);
	de->creation_date = de->write_date = de->read_date = gmt_to_local(dir->i_sb, CURRENT_TIME);
	if (!(mode & 0222)) de->read_only = 1;
	de->first = de->directory = 1;
	/*de->hidden = de->system = 0;*/
	de->fnode = fno;
	mark_buffer_dirty(bh);
	brelse(bh);
	hpfs_mark_4buffers_dirty(&qbh0);
	hpfs_brelse4(&qbh0);
	dir->i_nlink++;
	hpfs_lock_iget(dir->i_sb, 1);
	if ((result = iget(dir->i_sb, fno))) {
		result->i_hpfs_parent_dir = dir->i_ino;
		result->i_ctime = result->i_mtime = result->i_atime = local_to_gmt(dir->i_sb, dee.creation_date);
		result->i_hpfs_ea_size = 0;
		if (dee.read_only) result->i_mode &= ~0222;
		if (result->i_uid != current->fsuid ||
		    result->i_gid != current->fsgid ||
		    result->i_mode != (mode | S_IFDIR)) {
			result->i_uid = current->fsuid;
			result->i_gid = current->fsgid;
			result->i_mode = mode | S_IFDIR;
			hpfs_write_inode_nolock(result);
		}
		d_instantiate(dentry, result);
	}
	hpfs_unlock_iget(dir->i_sb);
	hpfs_unlock_inode(dir);
	return 0;
	bail2:
	hpfs_brelse4(&qbh0);
	hpfs_free_dnode(dir->i_sb, dno);
	hpfs_unlock_inode(dir);
	bail1:
	brelse(bh);
	hpfs_free_sectors(dir->i_sb, fno, 1);
	bail:
	return -ENOSPC;
}

int hpfs_create(struct inode *dir, struct dentry *dentry, int mode)
{
	const char *name = dentry->d_name.name;
	unsigned len = dentry->d_name.len;
	struct inode *result = NULL;
	struct buffer_head *bh;
	struct fnode *fnode;
	fnode_secno fno;
	int r;
	struct hpfs_dirent dee;
	int err;
	if ((err = hpfs_chk_name((char *)name, &len))) return err==-ENOENT ? -EINVAL : err;
	if (!(fnode = hpfs_alloc_fnode(dir->i_sb, dir->i_hpfs_dno, &fno, &bh))) goto bail;
	memset(&dee, 0, sizeof dee);
	if (!(mode & 0222)) dee.read_only = 1;
	dee.archive = 1;
	dee.hidden = name[0] == '.';
	dee.fnode = fno;
	dee.creation_date = dee.write_date = dee.read_date = gmt_to_local(dir->i_sb, CURRENT_TIME);
	hpfs_lock_inode(dir);
	r = hpfs_add_dirent(dir, (char *)name, len, &dee, 0);
	if (r == 1) goto bail1;
	if (r == -1) {
		brelse(bh);
		hpfs_free_sectors(dir->i_sb, fno, 1);
		hpfs_unlock_inode(dir);
		return -EEXIST;
	}
	fnode->len = len;
	memcpy(fnode->name, name, len > 15 ? 15 : len);
	fnode->up = dir->i_ino;
	mark_buffer_dirty(bh);
	brelse(bh);
	hpfs_lock_iget(dir->i_sb, 2);
	if ((result = iget(dir->i_sb, fno))) {
		hpfs_decide_conv(result, (char *)name, len);
		result->i_hpfs_parent_dir = dir->i_ino;
		result->i_ctime = result->i_mtime = result->i_atime = local_to_gmt(dir->i_sb, dee.creation_date);
		result->i_hpfs_ea_size = 0;
		if (dee.read_only) result->i_mode &= ~0222;
		if (result->i_blocks == -1) result->i_blocks = 1;
		if (result->i_size == -1) {
			result->i_size = 0;
			result->i_data.a_ops = &hpfs_aops;
			result->u.hpfs_i.mmu_private = 0;
		}
		if (result->i_uid != current->fsuid ||
		    result->i_gid != current->fsgid ||
		    result->i_mode != (mode | S_IFREG)) {
			result->i_uid = current->fsuid;
			result->i_gid = current->fsgid;
			result->i_mode = mode | S_IFREG;
			hpfs_write_inode_nolock(result);
		}
		d_instantiate(dentry, result);
	}
	hpfs_unlock_iget(dir->i_sb);
	hpfs_unlock_inode(dir);
	return 0;
	bail1:
	brelse(bh);
	hpfs_free_sectors(dir->i_sb, fno, 1);
	hpfs_unlock_inode(dir);
	bail:
	return -ENOSPC;
}

int hpfs_mknod(struct inode *dir, struct dentry *dentry, int mode, int rdev)
{
	const char *name = dentry->d_name.name;
	unsigned len = dentry->d_name.len;
	struct buffer_head *bh;
	struct fnode *fnode;
	fnode_secno fno;
	int r;
	struct hpfs_dirent dee;
	struct inode *result = NULL;
	int err;
	if ((err = hpfs_chk_name((char *)name, &len))) return err==-ENOENT ? -EINVAL : err;
	if (dir->i_sb->s_hpfs_eas < 2) return -EPERM;
	if (!(fnode = hpfs_alloc_fnode(dir->i_sb, dir->i_hpfs_dno, &fno, &bh))) goto bail;
	memset(&dee, 0, sizeof dee);
	if (!(mode & 0222)) dee.read_only = 1;
	dee.archive = 1;
	dee.hidden = name[0] == '.';
	dee.fnode = fno;
	dee.creation_date = dee.write_date = dee.read_date = gmt_to_local(dir->i_sb, CURRENT_TIME);
	hpfs_lock_inode(dir);
	r = hpfs_add_dirent(dir, (char *)name, len, &dee, 0);
	if (r == 1) goto bail1;
	if (r == -1) {
		brelse(bh);
		hpfs_free_sectors(dir->i_sb, fno, 1);
		hpfs_unlock_inode(dir);
		return -EEXIST;
	}
	fnode->len = len;
	memcpy(fnode->name, name, len > 15 ? 15 : len);
	fnode->up = dir->i_ino;
	mark_buffer_dirty(bh);
	hpfs_lock_iget(dir->i_sb, 2);
	if ((result = iget(dir->i_sb, fno))) {
		result->i_hpfs_parent_dir = dir->i_ino;
		result->i_ctime = result->i_mtime = result->i_atime = local_to_gmt(dir->i_sb, dee.creation_date);
		result->i_hpfs_ea_size = 0;
		/*if (result->i_blocks == -1) result->i_blocks = 1;
		if (result->i_size == -1) result->i_size = 0;*/
		result->i_uid = current->fsuid;
		result->i_gid = current->fsgid;
		result->i_nlink = 1;
		result->i_size = 0;
		result->i_blocks = 1;
		init_special_inode(result, mode, rdev);
		hpfs_write_inode_nolock(result);
		d_instantiate(dentry, result);
	}
	hpfs_unlock_iget(dir->i_sb);
	hpfs_unlock_inode(dir);
	brelse(bh);
	return 0;
	bail1:
	brelse(bh);
	hpfs_free_sectors(dir->i_sb, fno, 1);
	hpfs_unlock_inode(dir);
	bail:
	return -ENOSPC;
}

extern struct address_space_operations hpfs_symlink_aops;

int hpfs_symlink(struct inode *dir, struct dentry *dentry, const char *symlink)
{
	const char *name = dentry->d_name.name;
	unsigned len = dentry->d_name.len;
	struct buffer_head *bh;
	struct fnode *fnode;
	fnode_secno fno;
	int r;
	struct hpfs_dirent dee;
	struct inode *result;
	int err;
	if ((err = hpfs_chk_name((char *)name, &len))) return err==-ENOENT ? -EINVAL : err;
	if (dir->i_sb->s_hpfs_eas < 2) return -EPERM;
	if (!(fnode = hpfs_alloc_fnode(dir->i_sb, dir->i_hpfs_dno, &fno, &bh))) goto bail;
	memset(&dee, 0, sizeof dee);
	dee.archive = 1;
	dee.hidden = name[0] == '.';
	dee.fnode = fno;
	dee.creation_date = dee.write_date = dee.read_date = gmt_to_local(dir->i_sb, CURRENT_TIME);
	hpfs_lock_inode(dir);
	r = hpfs_add_dirent(dir, (char *)name, len, &dee, 0);
	if (r == 1) goto bail1;
	if (r == -1) {
		brelse(bh);
		hpfs_free_sectors(dir->i_sb, fno, 1);
		hpfs_unlock_inode(dir);
		return -EEXIST;
	}
	fnode->len = len;
	memcpy(fnode->name, name, len > 15 ? 15 : len);
	fnode->up = dir->i_ino;
	mark_buffer_dirty(bh);
	brelse(bh);
	hpfs_lock_iget(dir->i_sb, 2);
	if ((result = iget(dir->i_sb, fno))) {
		result->i_hpfs_parent_dir = dir->i_ino;
		result->i_ctime = result->i_mtime = result->i_atime = local_to_gmt(dir->i_sb, dee.creation_date);
		result->i_hpfs_ea_size = 0;
		/*if (result->i_blocks == -1) result->i_blocks = 1;