WSL2-Linux-Kernel/fs/hpfs/namei.c

649 строки
16 KiB
C

/*
* linux/fs/hpfs/namei.c
*
* Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999
*
* adding & removing files & directories
*/
#include <linux/sched.h>
#include "hpfs_fn.h"
static void hpfs_update_directory_times(struct inode *dir)
{
time_t t = get_seconds();
if (t == dir->i_mtime.tv_sec &&
t == dir->i_ctime.tv_sec)
return;
dir->i_mtime.tv_sec = dir->i_ctime.tv_sec = t;
dir->i_mtime.tv_nsec = dir->i_ctime.tv_nsec = 0;
hpfs_write_inode_nolock(dir);
}
static int hpfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
{
const unsigned 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(name, &len))) return err==-ENOENT ? -EINVAL : err;
hpfs_lock(dir->i_sb);
err = -ENOSPC;
fnode = hpfs_alloc_fnode(dir->i_sb, hpfs_i(dir)->i_dno, &fno, &bh);
if (!fnode)
goto bail;
dnode = hpfs_alloc_dnode(dir->i_sb, fno, &dno, &qbh0);
if (!dnode)
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 = cpu_to_le32(fno);
dee.creation_date = dee.write_date = dee.read_date = cpu_to_le32(gmt_to_local(dir->i_sb, get_seconds()));
result = new_inode(dir->i_sb);
if (!result)
goto bail2;
hpfs_init_inode(result);
result->i_ino = fno;
hpfs_i(result)->i_parent_dir = dir->i_ino;
hpfs_i(result)->i_dno = dno;
result->i_ctime.tv_sec = result->i_mtime.tv_sec = result->i_atime.tv_sec = local_to_gmt(dir->i_sb, le32_to_cpu(dee.creation_date));
result->i_ctime.tv_nsec = 0;
result->i_mtime.tv_nsec = 0;
result->i_atime.tv_nsec = 0;
hpfs_i(result)->i_ea_size = 0;
result->i_mode |= S_IFDIR;
result->i_op = &hpfs_dir_iops;
result->i_fop = &hpfs_dir_ops;
result->i_blocks = 4;
result->i_size = 2048;
set_nlink(result, 2);
if (dee.read_only)
result->i_mode &= ~0222;
r = hpfs_add_dirent(dir, name, len, &dee);
if (r == 1)
goto bail3;
if (r == -1) {
err = -EEXIST;
goto bail3;
}
fnode->len = len;
memcpy(fnode->name, name, len > 15 ? 15 : len);
fnode->up = cpu_to_le32(dir->i_ino);
fnode->flags |= FNODE_dir;
fnode->btree.n_free_nodes = 7;
fnode->btree.n_used_nodes = 1;
fnode->btree.first_free = cpu_to_le16(0x14);
fnode->u.external[0].disk_secno = cpu_to_le32(dno);
fnode->u.external[0].file_secno = cpu_to_le32(-1);
dnode->root_dnode = 1;
dnode->up = cpu_to_le32(fno);
de = hpfs_add_de(dir->i_sb, dnode, "\001\001", 2, 0);
de->creation_date = de->write_date = de->read_date = cpu_to_le32(gmt_to_local(dir->i_sb, get_seconds()));
if (!(mode & 0222)) de->read_only = 1;
de->first = de->directory = 1;
/*de->hidden = de->system = 0;*/
de->fnode = cpu_to_le32(fno);
mark_buffer_dirty(bh);
brelse(bh);
hpfs_mark_4buffers_dirty(&qbh0);
hpfs_brelse4(&qbh0);
inc_nlink(dir);
insert_inode_hash(result);
if (!uid_eq(result->i_uid, current_fsuid()) ||
!gid_eq(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);
}
hpfs_update_directory_times(dir);
d_instantiate(dentry, result);
hpfs_unlock(dir->i_sb);
return 0;
bail3:
iput(result);
bail2:
hpfs_brelse4(&qbh0);
hpfs_free_dnode(dir->i_sb, dno);
bail1:
brelse(bh);
hpfs_free_sectors(dir->i_sb, fno, 1);
bail:
hpfs_unlock(dir->i_sb);
return err;
}
static int hpfs_create(struct inode *dir, struct dentry *dentry, umode_t mode, bool excl)
{
const unsigned 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(name, &len)))
return err==-ENOENT ? -EINVAL : err;
hpfs_lock(dir->i_sb);
err = -ENOSPC;
fnode = hpfs_alloc_fnode(dir->i_sb, hpfs_i(dir)->i_dno, &fno, &bh);
if (!fnode)
goto bail;
memset(&dee, 0, sizeof dee);
if (!(mode & 0222)) dee.read_only = 1;
dee.archive = 1;
dee.hidden = name[0] == '.';
dee.fnode = cpu_to_le32(fno);
dee.creation_date = dee.write_date = dee.read_date = cpu_to_le32(gmt_to_local(dir->i_sb, get_seconds()));
result = new_inode(dir->i_sb);
if (!result)
goto bail1;
hpfs_init_inode(result);
result->i_ino = fno;
result->i_mode |= S_IFREG;
result->i_mode &= ~0111;
result->i_op = &hpfs_file_iops;
result->i_fop = &hpfs_file_ops;
set_nlink(result, 1);
hpfs_i(result)->i_parent_dir = dir->i_ino;
result->i_ctime.tv_sec = result->i_mtime.tv_sec = result->i_atime.tv_sec = local_to_gmt(dir->i_sb, le32_to_cpu(dee.creation_date));
result->i_ctime.tv_nsec = 0;
result->i_mtime.tv_nsec = 0;
result->i_atime.tv_nsec = 0;
hpfs_i(result)->i_ea_size = 0;
if (dee.read_only)
result->i_mode &= ~0222;
result->i_blocks = 1;
result->i_size = 0;
result->i_data.a_ops = &hpfs_aops;
hpfs_i(result)->mmu_private = 0;
r = hpfs_add_dirent(dir, name, len, &dee);
if (r == 1)
goto bail2;
if (r == -1) {
err = -EEXIST;
goto bail2;
}
fnode->len = len;
memcpy(fnode->name, name, len > 15 ? 15 : len);
fnode->up = cpu_to_le32(dir->i_ino);
mark_buffer_dirty(bh);
brelse(bh);
insert_inode_hash(result);
if (!uid_eq(result->i_uid, current_fsuid()) ||
!gid_eq(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);
}
hpfs_update_directory_times(dir);
d_instantiate(dentry, result);
hpfs_unlock(dir->i_sb);
return 0;
bail2:
iput(result);
bail1:
brelse(bh);
hpfs_free_sectors(dir->i_sb, fno, 1);
bail:
hpfs_unlock(dir->i_sb);
return err;
}
static int hpfs_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t rdev)
{
const unsigned 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(name, &len))) return err==-ENOENT ? -EINVAL : err;
if (hpfs_sb(dir->i_sb)->sb_eas < 2) return -EPERM;
hpfs_lock(dir->i_sb);
err = -ENOSPC;
fnode = hpfs_alloc_fnode(dir->i_sb, hpfs_i(dir)->i_dno, &fno, &bh);
if (!fnode)
goto bail;
memset(&dee, 0, sizeof dee);
if (!(mode & 0222)) dee.read_only = 1;
dee.archive = 1;
dee.hidden = name[0] == '.';
dee.fnode = cpu_to_le32(fno);
dee.creation_date = dee.write_date = dee.read_date = cpu_to_le32(gmt_to_local(dir->i_sb, get_seconds()));
result = new_inode(dir->i_sb);
if (!result)
goto bail1;
hpfs_init_inode(result);
result->i_ino = fno;
hpfs_i(result)->i_parent_dir = dir->i_ino;
result->i_ctime.tv_sec = result->i_mtime.tv_sec = result->i_atime.tv_sec = local_to_gmt(dir->i_sb, le32_to_cpu(dee.creation_date));
result->i_ctime.tv_nsec = 0;
result->i_mtime.tv_nsec = 0;
result->i_atime.tv_nsec = 0;
hpfs_i(result)->i_ea_size = 0;
result->i_uid = current_fsuid();
result->i_gid = current_fsgid();
set_nlink(result, 1);
result->i_size = 0;
result->i_blocks = 1;
init_special_inode(result, mode, rdev);
r = hpfs_add_dirent(dir, name, len, &dee);
if (r == 1)
goto bail2;
if (r == -1) {
err = -EEXIST;
goto bail2;
}
fnode->len = len;
memcpy(fnode->name, name, len > 15 ? 15 : len);
fnode->up = cpu_to_le32(dir->i_ino);
mark_buffer_dirty(bh);
insert_inode_hash(result);
hpfs_write_inode_nolock(result);
hpfs_update_directory_times(dir);
d_instantiate(dentry, result);
brelse(bh);
hpfs_unlock(dir->i_sb);
return 0;
bail2:
iput(result);
bail1:
brelse(bh);
hpfs_free_sectors(dir->i_sb, fno, 1);
bail:
hpfs_unlock(dir->i_sb);
return err;
}
static int hpfs_symlink(struct inode *dir, struct dentry *dentry, const char *symlink)
{
const unsigned 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(name, &len))) return err==-ENOENT ? -EINVAL : err;
hpfs_lock(dir->i_sb);
if (hpfs_sb(dir->i_sb)->sb_eas < 2) {
hpfs_unlock(dir->i_sb);
return -EPERM;
}
err = -ENOSPC;
fnode = hpfs_alloc_fnode(dir->i_sb, hpfs_i(dir)->i_dno, &fno, &bh);
if (!fnode)
goto bail;
memset(&dee, 0, sizeof dee);
dee.archive = 1;
dee.hidden = name[0] == '.';
dee.fnode = cpu_to_le32(fno);
dee.creation_date = dee.write_date = dee.read_date = cpu_to_le32(gmt_to_local(dir->i_sb, get_seconds()));
result = new_inode(dir->i_sb);
if (!result)
goto bail1;
result->i_ino = fno;
hpfs_init_inode(result);
hpfs_i(result)->i_parent_dir = dir->i_ino;
result->i_ctime.tv_sec = result->i_mtime.tv_sec = result->i_atime.tv_sec = local_to_gmt(dir->i_sb, le32_to_cpu(dee.creation_date));
result->i_ctime.tv_nsec = 0;
result->i_mtime.tv_nsec = 0;
result->i_atime.tv_nsec = 0;
hpfs_i(result)->i_ea_size = 0;
result->i_mode = S_IFLNK | 0777;
result->i_uid = current_fsuid();
result->i_gid = current_fsgid();
result->i_blocks = 1;
set_nlink(result, 1);
result->i_size = strlen(symlink);
inode_nohighmem(result);
result->i_op = &page_symlink_inode_operations;
result->i_data.a_ops = &hpfs_symlink_aops;
r = hpfs_add_dirent(dir, name, len, &dee);
if (r == 1)
goto bail2;
if (r == -1) {
err = -EEXIST;
goto bail2;
}
fnode->len = len;
memcpy(fnode->name, name, len > 15 ? 15 : len);
fnode->up = cpu_to_le32(dir->i_ino);
hpfs_set_ea(result, fnode, "SYMLINK", symlink, strlen(symlink));
mark_buffer_dirty(bh);
brelse(bh);
insert_inode_hash(result);
hpfs_write_inode_nolock(result);
hpfs_update_directory_times(dir);
d_instantiate(dentry, result);
hpfs_unlock(dir->i_sb);
return 0;
bail2:
iput(result);
bail1:
brelse(bh);
hpfs_free_sectors(dir->i_sb, fno, 1);
bail:
hpfs_unlock(dir->i_sb);
return err;
}
static int hpfs_unlink(struct inode *dir, struct dentry *dentry)
{
const unsigned char *name = dentry->d_name.name;
unsigned len = dentry->d_name.len;
struct quad_buffer_head qbh;
struct hpfs_dirent *de;
struct inode *inode = d_inode(dentry);
dnode_secno dno;
int r;
int rep = 0;
int err;
hpfs_lock(dir->i_sb);
hpfs_adjust_length(name, &len);
again:
err = -ENOENT;
de = map_dirent(dir, hpfs_i(dir)->i_dno, name, len, &dno, &qbh);
if (!de)
goto out;
err = -EPERM;
if (de->first)
goto out1;
err = -EISDIR;
if (de->directory)
goto out1;
r = hpfs_remove_dirent(dir, dno, de, &qbh, 1);
switch (r) {
case 1:
hpfs_error(dir->i_sb, "there was error when removing dirent");
err = -EFSERROR;
break;
case 2: /* no space for deleting, try to truncate file */
err = -ENOSPC;
if (rep++)
break;
dentry_unhash(dentry);
if (!d_unhashed(dentry)) {
hpfs_unlock(dir->i_sb);
return -ENOSPC;
}
if (generic_permission(inode, MAY_WRITE) ||
!S_ISREG(inode->i_mode) ||
get_write_access(inode)) {
d_rehash(dentry);
} else {
struct iattr newattrs;
/*pr_info("truncating file before delete.\n");*/
newattrs.ia_size = 0;
newattrs.ia_valid = ATTR_SIZE | ATTR_CTIME;
err = notify_change(dentry, &newattrs, NULL);
put_write_access(inode);
if (!err)
goto again;
}
hpfs_unlock(dir->i_sb);
return -ENOSPC;
default:
drop_nlink(inode);
err = 0;
}
goto out;
out1:
hpfs_brelse4(&qbh);
out:
if (!err)
hpfs_update_directory_times(dir);
hpfs_unlock(dir->i_sb);
return err;
}
static int hpfs_rmdir(struct inode *dir, struct dentry *dentry)
{
const unsigned char *name = dentry->d_name.name;
unsigned len = dentry->d_name.len;
struct quad_buffer_head qbh;
struct hpfs_dirent *de;
struct inode *inode = d_inode(dentry);
dnode_secno dno;
int n_items = 0;
int err;
int r;
hpfs_adjust_length(name, &len);
hpfs_lock(dir->i_sb);
err = -ENOENT;
de = map_dirent(dir, hpfs_i(dir)->i_dno, name, len, &dno, &qbh);
if (!de)
goto out;
err = -EPERM;
if (de->first)
goto out1;
err = -ENOTDIR;
if (!de->directory)
goto out1;
hpfs_count_dnodes(dir->i_sb, hpfs_i(inode)->i_dno, NULL, NULL, &n_items);
err = -ENOTEMPTY;
if (n_items)
goto out1;
r = hpfs_remove_dirent(dir, dno, de, &qbh, 1);
switch (r) {
case 1:
hpfs_error(dir->i_sb, "there was error when removing dirent");
err = -EFSERROR;
break;
case 2:
err = -ENOSPC;
break;
default:
drop_nlink(dir);
clear_nlink(inode);
err = 0;
}
goto out;
out1:
hpfs_brelse4(&qbh);
out:
if (!err)
hpfs_update_directory_times(dir);
hpfs_unlock(dir->i_sb);
return err;
}
static int hpfs_symlink_readpage(struct file *file, struct page *page)
{
char *link = page_address(page);
struct inode *i = page->mapping->host;
struct fnode *fnode;
struct buffer_head *bh;
int err;
err = -EIO;
hpfs_lock(i->i_sb);
if (!(fnode = hpfs_map_fnode(i->i_sb, i->i_ino, &bh)))
goto fail;
err = hpfs_read_ea(i->i_sb, fnode, "SYMLINK", link, PAGE_SIZE);
brelse(bh);
if (err)
goto fail;
hpfs_unlock(i->i_sb);
SetPageUptodate(page);
unlock_page(page);
return 0;
fail:
hpfs_unlock(i->i_sb);
SetPageError(page);
unlock_page(page);
return err;
}
const struct address_space_operations hpfs_symlink_aops = {
.readpage = hpfs_symlink_readpage
};
static int hpfs_rename(struct inode *old_dir, struct dentry *old_dentry,
struct inode *new_dir, struct dentry *new_dentry)
{
const unsigned char *old_name = old_dentry->d_name.name;
unsigned old_len = old_dentry->d_name.len;
const unsigned char *new_name = new_dentry->d_name.name;
unsigned new_len = new_dentry->d_name.len;
struct inode *i = d_inode(old_dentry);
struct inode *new_inode = d_inode(new_dentry);
struct quad_buffer_head qbh, qbh1;
struct hpfs_dirent *dep, *nde;
struct hpfs_dirent de;
dnode_secno dno;
int r;
struct buffer_head *bh;
struct fnode *fnode;
int err;
if ((err = hpfs_chk_name(new_name, &new_len))) return err;
err = 0;
hpfs_adjust_length(old_name, &old_len);
hpfs_lock(i->i_sb);
/* order doesn't matter, due to VFS exclusion */
/* Erm? Moving over the empty non-busy directory is perfectly legal */
if (new_inode && S_ISDIR(new_inode->i_mode)) {
err = -EINVAL;
goto end1;
}
if (!(dep = map_dirent(old_dir, hpfs_i(old_dir)->i_dno, old_name, old_len, &dno, &qbh))) {
hpfs_error(i->i_sb, "lookup succeeded but map dirent failed");
err = -ENOENT;
goto end1;
}
copy_de(&de, dep);
de.hidden = new_name[0] == '.';
if (new_inode) {
int r;
if ((r = hpfs_remove_dirent(old_dir, dno, dep, &qbh, 1)) != 2) {
if ((nde = map_dirent(new_dir, hpfs_i(new_dir)->i_dno, new_name, new_len, NULL, &qbh1))) {
clear_nlink(new_inode);
copy_de(nde, &de);
memcpy(nde->name, new_name, new_len);
hpfs_mark_4buffers_dirty(&qbh1);
hpfs_brelse4(&qbh1);
goto end;
}
hpfs_error(new_dir->i_sb, "hpfs_rename: could not find dirent");
err = -EFSERROR;
goto end1;
}
err = r == 2 ? -ENOSPC : r == 1 ? -EFSERROR : 0;
goto end1;
}
if (new_dir == old_dir) hpfs_brelse4(&qbh);
if ((r = hpfs_add_dirent(new_dir, new_name, new_len, &de))) {
if (r == -1) hpfs_error(new_dir->i_sb, "hpfs_rename: dirent already exists!");
err = r == 1 ? -ENOSPC : -EFSERROR;
if (new_dir != old_dir) hpfs_brelse4(&qbh);
goto end1;
}
if (new_dir == old_dir)
if (!(dep = map_dirent(old_dir, hpfs_i(old_dir)->i_dno, old_name, old_len, &dno, &qbh))) {
hpfs_error(i->i_sb, "lookup succeeded but map dirent failed at #2");
err = -ENOENT;
goto end1;
}
if ((r = hpfs_remove_dirent(old_dir, dno, dep, &qbh, 0))) {
hpfs_error(i->i_sb, "hpfs_rename: could not remove dirent");
err = r == 2 ? -ENOSPC : -EFSERROR;
goto end1;
}
end:
hpfs_i(i)->i_parent_dir = new_dir->i_ino;
if (S_ISDIR(i->i_mode)) {
inc_nlink(new_dir);
drop_nlink(old_dir);
}
if ((fnode = hpfs_map_fnode(i->i_sb, i->i_ino, &bh))) {
fnode->up = cpu_to_le32(new_dir->i_ino);
fnode->len = new_len;
memcpy(fnode->name, new_name, new_len>15?15:new_len);
if (new_len < 15) memset(&fnode->name[new_len], 0, 15 - new_len);
mark_buffer_dirty(bh);
brelse(bh);
}
end1:
if (!err) {
hpfs_update_directory_times(old_dir);
hpfs_update_directory_times(new_dir);
}
hpfs_unlock(i->i_sb);
return err;
}
const struct inode_operations hpfs_dir_iops =
{
.create = hpfs_create,
.lookup = hpfs_lookup,
.unlink = hpfs_unlink,
.symlink = hpfs_symlink,
.mkdir = hpfs_mkdir,
.rmdir = hpfs_rmdir,
.mknod = hpfs_mknod,
.rename = hpfs_rename,
.setattr = hpfs_setattr,
};