alistair23-linux/fs/hpfs/namei.c
Arnd Bergmann 9a311b96c3 hpfs: remove the BKL
This removes the BKL in hpfs in a rather awful
way, by making the code only work on uniprocessor
systems without kernel preemption, as suggested
by Andi Kleen.

The HPFS code probably has close to zero remaining
users on current kernels, all archeological uses of
the file system can probably be done with the significant
restrictions.

The hpfs_lock/hpfs_unlock functions are left in the
code, sincen Mikulas has indicated that he is still
interested in fixing it in a better way.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Andi Kleen <ak@linux.intel.com>
Cc: Mikulas Patocka <mikulas@artax.karlin.mff.cuni.cz>
Cc: linux-fsdevel@vger.kernel.org
2011-03-02 22:27:36 +01:00

677 lines
17 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 int hpfs_mkdir(struct inode *dir, struct dentry *dentry, int 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, 1);
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 = fno;
dee.creation_date = dee.write_date = dee.read_date = 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, 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;
result->i_nlink = 2;
if (dee.read_only)
result->i_mode &= ~0222;
mutex_lock(&hpfs_i(dir)->i_mutex);
r = hpfs_add_dirent(dir, name, len, &dee, 0);
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 = 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, get_seconds());
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);
inc_nlink(dir);
insert_inode_hash(result);
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);
mutex_unlock(&hpfs_i(dir)->i_mutex);
hpfs_unlock(dir->i_sb);
return 0;
bail3:
mutex_unlock(&hpfs_i(dir)->i_mutex);
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, int mode, struct nameidata *nd)
{
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 = fno;
dee.creation_date = dee.write_date = dee.read_date = 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;
result->i_nlink = 1;
hpfs_decide_conv(result, name, len);
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, 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;
mutex_lock(&hpfs_i(dir)->i_mutex);
r = hpfs_add_dirent(dir, name, len, &dee, 0);
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 = dir->i_ino;
mark_buffer_dirty(bh);
brelse(bh);
insert_inode_hash(result);
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);
mutex_unlock(&hpfs_i(dir)->i_mutex);
hpfs_unlock(dir->i_sb);
return 0;
bail2:
mutex_unlock(&hpfs_i(dir)->i_mutex);
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, int 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;
if (!new_valid_dev(rdev))
return -EINVAL;
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 = fno;
dee.creation_date = dee.write_date = dee.read_date = 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, 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();
result->i_nlink = 1;
result->i_size = 0;
result->i_blocks = 1;
init_special_inode(result, mode, rdev);
mutex_lock(&hpfs_i(dir)->i_mutex);
r = hpfs_add_dirent(dir, name, len, &dee, 0);
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 = dir->i_ino;
mark_buffer_dirty(bh);
insert_inode_hash(result);
hpfs_write_inode_nolock(result);
d_instantiate(dentry, result);
mutex_unlock(&hpfs_i(dir)->i_mutex);
brelse(bh);
hpfs_unlock(dir->i_sb);
return 0;
bail2:
mutex_unlock(&hpfs_i(dir)->i_mutex);
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 = fno;
dee.creation_date = dee.write_date = dee.read_date = 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, 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;
result->i_nlink = 1;
result->i_size = strlen(symlink);
result->i_op = &page_symlink_inode_operations;
result->i_data.a_ops = &hpfs_symlink_aops;
mutex_lock(&hpfs_i(dir)->i_mutex);
r = hpfs_add_dirent(dir, name, len, &dee, 0);
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 = 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);
d_instantiate(dentry, result);
mutex_unlock(&hpfs_i(dir)->i_mutex);
hpfs_unlock(dir->i_sb);
return 0;
bail2:
mutex_unlock(&hpfs_i(dir)->i_mutex);
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 = dentry->d_inode;
dnode_secno dno;
fnode_secno fno;
int r;
int rep = 0;
int err;
hpfs_lock(dir->i_sb);
hpfs_adjust_length(name, &len);
again:
mutex_lock(&hpfs_i(inode)->i_parent_mutex);
mutex_lock(&hpfs_i(dir)->i_mutex);
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;
fno = de->fnode;
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;
mutex_unlock(&hpfs_i(dir)->i_mutex);
mutex_unlock(&hpfs_i(inode)->i_parent_mutex);
dentry_unhash(dentry);
if (!d_unhashed(dentry)) {
dput(dentry);
hpfs_unlock(dir->i_sb);
return -ENOSPC;
}
if (generic_permission(inode, MAY_WRITE, 0, NULL) ||
!S_ISREG(inode->i_mode) ||
get_write_access(inode)) {
d_rehash(dentry);
dput(dentry);
} else {
struct iattr newattrs;
/*printk("HPFS: truncating file before delete.\n");*/
newattrs.ia_size = 0;
newattrs.ia_valid = ATTR_SIZE | ATTR_CTIME;
err = notify_change(dentry, &newattrs);
put_write_access(inode);
dput(dentry);
if (!err)
goto again;
}
hpfs_unlock(dir->i_sb);
return -ENOSPC;
default:
drop_nlink(inode);
err = 0;
}
goto out;
out1:
hpfs_brelse4(&qbh);
out:
mutex_unlock(&hpfs_i(dir)->i_mutex);
mutex_unlock(&hpfs_i(inode)->i_parent_mutex);
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 = dentry->d_inode;
dnode_secno dno;
fnode_secno fno;
int n_items = 0;
int err;
int r;
hpfs_adjust_length(name, &len);
hpfs_lock(dir->i_sb);
mutex_lock(&hpfs_i(inode)->i_parent_mutex);
mutex_lock(&hpfs_i(dir)->i_mutex);
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;
fno = de->fnode;
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:
mutex_unlock(&hpfs_i(dir)->i_mutex);
mutex_unlock(&hpfs_i(inode)->i_parent_mutex);
hpfs_unlock(dir->i_sb);
return err;
}
static int hpfs_symlink_readpage(struct file *file, struct page *page)
{
char *link = kmap(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);
kunmap(page);
unlock_page(page);
return 0;
fail:
hpfs_unlock(i->i_sb);
SetPageError(page);
kunmap(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 = old_dentry->d_inode;
struct inode *new_inode = new_dentry->d_inode;
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 */
mutex_lock(&hpfs_i(i)->i_parent_mutex);
if (new_inode)
mutex_lock(&hpfs_i(new_inode)->i_parent_mutex);
mutex_lock(&hpfs_i(old_dir)->i_mutex);
if (new_dir != old_dir)
mutex_lock(&hpfs_i(new_dir)->i_mutex);
/* 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);
hpfs_lock_creation(i->i_sb);
if ((r = hpfs_add_dirent(new_dir, new_name, new_len, &de, 1))) {
hpfs_unlock_creation(i->i_sb);
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_unlock_creation(i->i_sb);
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_unlock_creation(i->i_sb);
hpfs_error(i->i_sb, "hpfs_rename: could not remove dirent");
err = r == 2 ? -ENOSPC : -EFSERROR;
goto end1;
}
hpfs_unlock_creation(i->i_sb);
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 = 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);
}
hpfs_i(i)->i_conv = hpfs_sb(i->i_sb)->sb_conv;
hpfs_decide_conv(i, new_name, new_len);
end1:
if (old_dir != new_dir)
mutex_unlock(&hpfs_i(new_dir)->i_mutex);
mutex_unlock(&hpfs_i(old_dir)->i_mutex);
mutex_unlock(&hpfs_i(i)->i_parent_mutex);
if (new_inode)
mutex_unlock(&hpfs_i(new_inode)->i_parent_mutex);
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,
};