int fcntl_dirnotify(int fd, struct file *filp, unsigned long arg)
{
struct dnotify_struct *dn;
struct dnotify_struct *odn;
struct dnotify_struct **prev;
struct inode *inode;
fl_owner_t id = current->files;
int error = 0;
if ((arg & ~DN_MULTISHOT) == 0) {
dnotify_flush(filp, id);
return 0;
}
if (!dir_notify_enable)
return -EINVAL;
inode = filp->f_dentry->d_inode;
if (!S_ISDIR(inode->i_mode))
return -ENOTDIR;
dn = kmem_cache_alloc(dn_cache, SLAB_KERNEL);
if (dn == NULL)
return -ENOMEM;
spin_lock(&inode->i_lock);
prev = &inode->i_dnotify;
while ((odn = *prev) != NULL) {
if ((odn->dn_owner == id) && (odn->dn_filp == filp)) {
odn->dn_fd = fd;
odn->dn_mask |= arg;
inode->i_dnotify_mask |= arg & ~DN_MULTISHOT;
goto out_free;
}
prev = &odn->dn_next;
}
error = f_setown(filp, current->pid, 0);
if (error)
goto out_free;
dn->dn_mask = arg;
dn->dn_fd = fd;
dn->dn_filp = filp;
dn->dn_owner = id;
inode->i_dnotify_mask |= arg & ~DN_MULTISHOT;
dn->dn_next = inode->i_dnotify;
inode->i_dnotify = dn;
spin_unlock(&inode->i_lock);
if (filp->f_op && filp->f_op->dir_notify)
return filp->f_op->dir_notify(filp, arg);
return 0;
out_free:
spin_unlock(&inode->i_lock);
kmem_cache_free(dn_cache, dn);
return error;
}
static long do_fcntl(int fd, unsigned int cmd, unsigned long arg,
struct file *filp)
{
long err = -EINVAL;
switch (cmd) {
case F_DUPFD:
err = f_dupfd(arg, filp, 0);
break;
case F_DUPFD_CLOEXEC:
err = f_dupfd(arg, filp, O_CLOEXEC);
break;
case F_GETFD:
err = get_close_on_exec(fd) ? FD_CLOEXEC : 0;
break;
case F_SETFD:
err = 0;
set_close_on_exec(fd, arg & FD_CLOEXEC);
break;
case F_GETFL:
err = filp->f_flags;
break;
case F_SETFL:
err = setfl(fd, filp, arg);
break;
#if BITS_PER_LONG != 32
/* 32-bit arches must use fcntl64() */
case F_OFD_GETLK:
#endif
case F_GETLK:
err = fcntl_getlk(filp, cmd, (struct flock __user *) arg);
break;
#if BITS_PER_LONG != 32
/* 32-bit arches must use fcntl64() */
case F_OFD_SETLK:
case F_OFD_SETLKW:
#endif
/* Fallthrough */
case F_SETLK:
case F_SETLKW:
err = fcntl_setlk(fd, filp, cmd, (struct flock __user *) arg);
break;
case F_GETOWN:
/*
* XXX If f_owner is a process group, the
* negative return value will get converted
* into an error. Oops. If we keep the
* current syscall conventions, the only way
* to fix this will be in libc.
*/
err = f_getown(filp);
force_successful_syscall_return();
break;
case F_SETOWN:
err = f_setown(filp, arg, 1);
break;
case F_GETOWN_EX:
err = f_getown_ex(filp, arg);
break;
case F_SETOWN_EX:
err = f_setown_ex(filp, arg);
break;
case F_GETOWNER_UIDS:
err = f_getowner_uids(filp, arg);
break;
case F_GETSIG:
err = filp->f_owner.signum;
break;
case F_SETSIG:
/* arg == 0 restores default behaviour. */
if (!valid_signal(arg)) {
break;
}
err = 0;
filp->f_owner.signum = arg;
break;
case F_GETLEASE:
err = fcntl_getlease(filp);
break;
case F_SETLEASE:
err = fcntl_setlease(fd, filp, arg);
break;
case F_NOTIFY:
err = fcntl_dirnotify(fd, filp, arg);
break;
case F_SETPIPE_SZ:
case F_GETPIPE_SZ:
err = pipe_fcntl(filp, cmd, arg);
break;
case F_ADD_SEALS:
case F_GET_SEALS:
err = shmem_fcntl(filp, cmd, arg);
break;
default:
break;
}
return err;
}
int fcntl_dirnotify(int fd, struct file *filp, unsigned long arg)
{
struct dnotify_struct *dn;
struct dnotify_struct *odn;
struct dnotify_struct **prev;
struct inode *inode;
fl_owner_t id = current->files;
struct file *f;
int error = 0;
if ((arg & ~DN_MULTISHOT) == 0) {
dnotify_flush(filp, id);
return 0;
}
if (!dir_notify_enable)
return -EINVAL;
inode = filp->f_dentry->d_inode;
if (!S_ISDIR(inode->i_mode))
return -ENOTDIR;
dn = kmem_cache_alloc(dn_cache, SLAB_KERNEL);
if (dn == NULL)
return -ENOMEM;
spin_lock(&inode->i_lock);
prev = &inode->i_dnotify;
while ((odn = *prev) != NULL) {
if ((odn->dn_owner == id) && (odn->dn_filp == filp)) {
odn->dn_fd = fd;
odn->dn_mask |= arg;
inode->i_dnotify_mask |= arg & ~DN_MULTISHOT;
goto out_free;
}
prev = &odn->dn_next;
}
rcu_read_lock();
f = fcheck(fd);
rcu_read_unlock();
/* we'd lost the race with close(), sod off silently */
/* note that inode->i_lock prevents reordering problems
* between accesses to descriptor table and ->i_dnotify */
if (f != filp)
goto out_free;
error = f_setown(filp, current->pid, 0);
if (error)
goto out_free;
dn->dn_mask = arg;
dn->dn_fd = fd;
dn->dn_filp = filp;
dn->dn_owner = id;
inode->i_dnotify_mask |= arg & ~DN_MULTISHOT;
dn->dn_next = inode->i_dnotify;
inode->i_dnotify = dn;
spin_unlock(&inode->i_lock);
if (filp->f_op && filp->f_op->dir_notify)
return filp->f_op->dir_notify(filp, arg);
return 0;
out_free:
spin_unlock(&inode->i_lock);
kmem_cache_free(dn_cache, dn);
return error;
}