* We don't provide read/write/poll interface for user space.
*/
static ssize_t hci_uart_tty_read(struct tty_struct *tty, struct file *file,
- unsigned char __user *buf, size_t nr)
+ unsigned char *buf, size_t nr,
+ void **cookie, unsigned long offset)
{
return 0;
}
return 0;
}
+static struct tty_ldisc_ops hci_uart_ldisc = {
+ .owner = THIS_MODULE,
+ .magic = TTY_LDISC_MAGIC,
+ .name = "n_hci",
+ .open = hci_uart_tty_open,
+ .close = hci_uart_tty_close,
+ .read = hci_uart_tty_read,
+ .write = hci_uart_tty_write,
+ .ioctl = hci_uart_tty_ioctl,
+ .compat_ioctl = hci_uart_tty_ioctl,
+ .poll = hci_uart_tty_poll,
+ .receive_buf = hci_uart_tty_receive,
+ .write_wakeup = hci_uart_tty_wakeup,
+};
+
static int __init hci_uart_init(void)
{
- static struct tty_ldisc_ops hci_uart_ldisc;
int err;
BT_INFO("HCI UART driver ver %s", VERSION);
/* Register the tty discipline */
-
- memset(&hci_uart_ldisc, 0, sizeof(hci_uart_ldisc));
- hci_uart_ldisc.magic = TTY_LDISC_MAGIC;
- hci_uart_ldisc.name = "n_hci";
- hci_uart_ldisc.open = hci_uart_tty_open;
- hci_uart_ldisc.close = hci_uart_tty_close;
- hci_uart_ldisc.read = hci_uart_tty_read;
- hci_uart_ldisc.write = hci_uart_tty_write;
- hci_uart_ldisc.ioctl = hci_uart_tty_ioctl;
- hci_uart_ldisc.compat_ioctl = hci_uart_tty_ioctl;
- hci_uart_ldisc.poll = hci_uart_tty_poll;
- hci_uart_ldisc.receive_buf = hci_uart_tty_receive;
- hci_uart_ldisc.write_wakeup = hci_uart_tty_wakeup;
- hci_uart_ldisc.owner = THIS_MODULE;
-
err = tty_register_ldisc(N_HCI, &hci_uart_ldisc);
if (err) {
BT_ERR("HCI line discipline registration failed. (%d)", err);
* returning 0 characters.
*/
-static ssize_t serport_ldisc_read(struct tty_struct * tty, struct file * file, unsigned char __user * buf, size_t nr)
+static ssize_t serport_ldisc_read(struct tty_struct * tty, struct file * file,
+ unsigned char *kbuf, size_t nr,
+ void **cookie, unsigned long offset)
{
struct serport *serport = (struct serport*) tty->disc_data;
struct serio *serio;
*/
static ssize_t
ppp_asynctty_read(struct tty_struct *tty, struct file *file,
- unsigned char __user *buf, size_t count)
+ unsigned char *buf, size_t count,
+ void **cookie, unsigned long offset)
{
return -EAGAIN;
}
*/
static ssize_t
ppp_sync_read(struct tty_struct *tty, struct file *file,
- unsigned char __user *buf, size_t count)
+ unsigned char *buf, size_t count,
+ void **cookie, unsigned long offset)
{
return -EAGAIN;
}
*/
static ssize_t gsmld_read(struct tty_struct *tty, struct file *file,
- unsigned char __user *buf, size_t nr)
+ unsigned char *buf, size_t nr,
+ void **cookie, unsigned long offset)
{
return -EOPNOTSUPP;
}
* Returns the number of bytes returned or error code.
*/
static ssize_t n_hdlc_tty_read(struct tty_struct *tty, struct file *file,
- __u8 __user *buf, size_t nr)
+ __u8 *kbuf, size_t nr,
+ void **cookie, unsigned long offset)
{
struct n_hdlc *n_hdlc = tty->disc_data;
int ret = 0;
struct n_hdlc_buf *rbuf;
DECLARE_WAITQUEUE(wait, current);
+ /* Is this a repeated call for an rbuf we already found earlier? */
+ rbuf = *cookie;
+ if (rbuf)
+ goto have_rbuf;
+
add_wait_queue(&tty->read_wait, &wait);
for (;;) {
set_current_state(TASK_INTERRUPTIBLE);
rbuf = n_hdlc_buf_get(&n_hdlc->rx_buf_list);
- if (rbuf) {
- if (rbuf->count > nr) {
- /* too large for caller's buffer */
- ret = -EOVERFLOW;
- } else {
- __set_current_state(TASK_RUNNING);
- if (copy_to_user(buf, rbuf->buf, rbuf->count))
- ret = -EFAULT;
- else
- ret = rbuf->count;
- }
-
- if (n_hdlc->rx_free_buf_list.count >
- DEFAULT_RX_BUF_COUNT)
- kfree(rbuf);
- else
- n_hdlc_buf_put(&n_hdlc->rx_free_buf_list, rbuf);
+ if (rbuf)
break;
- }
/* no data */
if (tty_io_nonblock(tty, file)) {
remove_wait_queue(&tty->read_wait, &wait);
__set_current_state(TASK_RUNNING);
+ if (!rbuf)
+ return ret;
+ *cookie = rbuf;
+
+have_rbuf:
+ /* Have we used it up entirely? */
+ if (offset >= rbuf->count)
+ goto done_with_rbuf;
+
+ /* More data to go, but can't copy any more? EOVERFLOW */
+ ret = -EOVERFLOW;
+ if (!nr)
+ goto done_with_rbuf;
+
+ /* Copy as much data as possible */
+ ret = rbuf->count - offset;
+ if (ret > nr)
+ ret = nr;
+ memcpy(kbuf, rbuf->buf+offset, ret);
+ offset += ret;
+
+ /* If we still have data left, we leave the rbuf in the cookie */
+ if (offset < rbuf->count)
+ return ret;
+
+done_with_rbuf:
+ *cookie = NULL;
+
+ if (n_hdlc->rx_free_buf_list.count > DEFAULT_RX_BUF_COUNT)
+ kfree(rbuf);
+ else
+ n_hdlc_buf_put(&n_hdlc->rx_free_buf_list, rbuf);
+
return ret;
} /* end of n_hdlc_tty_read() */
}
static ssize_t n_null_read(struct tty_struct *tty, struct file *file,
- unsigned char __user * buf, size_t nr)
+ unsigned char *buf, size_t nr,
+ void **cookie, unsigned long offset)
{
return -EOPNOTSUPP;
}
static int r3964_open(struct tty_struct *tty);
static void r3964_close(struct tty_struct *tty);
static ssize_t r3964_read(struct tty_struct *tty, struct file *file,
- unsigned char __user * buf, size_t nr);
+ void *cookie, unsigned char *buf, size_t nr);
static ssize_t r3964_write(struct tty_struct *tty, struct file *file,
const unsigned char *buf, size_t nr);
static int r3964_ioctl(struct tty_struct *tty, struct file *file,
}
static ssize_t r3964_read(struct tty_struct *tty, struct file *file,
- unsigned char __user * buf, size_t nr)
+ unsigned char *kbuf, size_t nr,
+ void **cookie, unsigned long offset)
{
struct r3964_info *pInfo = tty->disc_data;
struct r3964_client_info *pClient;
kfree(pMsg);
TRACE_M("r3964_read - msg kfree %p", pMsg);
- if (copy_to_user(buf, &theMsg, ret)) {
- ret = -EFAULT;
- goto unlock;
- }
+ memcpy(kbuf, &theMsg, ret);
TRACE_PS("read - return %d", ret);
goto unlock;
* -EINVAL
*/
static ssize_t n_tracerouter_read(struct tty_struct *tty, struct file *file,
- unsigned char __user *buf, size_t nr) {
+ unsigned char *buf, size_t nr,
+ void **cookie, unsigned long offset)
+{
return -EINVAL;
}
* -EINVAL
*/
static ssize_t n_tracesink_read(struct tty_struct *tty, struct file *file,
- unsigned char __user *buf, size_t nr) {
+ unsigned char *buf, size_t nr,
+ void **cookie, unsigned long offset)
+{
return -EINVAL;
}
memset(buffer, 0x00, size);
}
-static int tty_copy_to_user(struct tty_struct *tty, void __user *to,
- size_t tail, size_t n)
+static void tty_copy(struct tty_struct *tty, void *to, size_t tail, size_t n)
{
struct n_tty_data *ldata = tty->disc_data;
size_t size = N_TTY_BUF_SIZE - tail;
void *from = read_buf_addr(ldata, tail);
- int uncopied;
if (n > size) {
tty_audit_add_data(tty, from, size);
- uncopied = copy_to_user(to, from, size);
- zero_buffer(tty, from, size - uncopied);
- if (uncopied)
- return uncopied;
+ memcpy(to, from, size);
+ zero_buffer(tty, from, size);
to += size;
n -= size;
from = ldata->read_buf;
}
tty_audit_add_data(tty, from, n);
- uncopied = copy_to_user(to, from, n);
- zero_buffer(tty, from, n - uncopied);
- return uncopied;
+ memcpy(to, from, n);
+ zero_buffer(tty, from, n);
}
/**
/**
* copy_from_read_buf - copy read data directly
* @tty: terminal device
- * @b: user data
+ * @kbp: data
* @nr: size of data
*
* Helper function to speed up n_tty_read. It is only called when
- * ICANON is off; it copies characters straight from the tty queue to
- * user space directly. It can be profitably called twice; once to
- * drain the space from the tail pointer to the (physical) end of the
- * buffer, and once to drain the space from the (physical) beginning of
- * the buffer to head pointer.
+ * ICANON is off; it copies characters straight from the tty queue.
+ *
+ * It can be profitably called twice; once to drain the space from
+ * the tail pointer to the (physical) end of the buffer, and once
+ * to drain the space from the (physical) beginning of the buffer
+ * to head pointer.
*
* Called under the ldata->atomic_read_lock sem
*
*/
static int copy_from_read_buf(struct tty_struct *tty,
- unsigned char __user **b,
+ unsigned char **kbp,
size_t *nr)
{
n = min(*nr, n);
if (n) {
unsigned char *from = read_buf_addr(ldata, tail);
- retval = copy_to_user(*b, from, n);
- n -= retval;
+ memcpy(*kbp, from, n);
is_eof = n == 1 && *from == EOF_CHAR(tty);
tty_audit_add_data(tty, from, n);
zero_buffer(tty, from, n);
if (L_EXTPROC(tty) && ldata->icanon && is_eof &&
(head == ldata->read_tail))
n = 0;
- *b += n;
+ *kbp += n;
*nr -= n;
}
return retval;
/**
* canon_copy_from_read_buf - copy read data in canonical mode
* @tty: terminal device
- * @b: user data
+ * @kbp: data
* @nr: size of data
*
* Helper function for n_tty_read. It is only called when ICANON is on;
* it copies one line of input up to and including the line-delimiting
- * character into the user-space buffer.
+ * character into the result buffer.
*
* NB: When termios is changed from non-canonical to canonical mode and
* the read buffer contains data, n_tty_set_termios() simulates an EOF
*/
static int canon_copy_from_read_buf(struct tty_struct *tty,
- unsigned char __user **b,
+ unsigned char **kbp,
size_t *nr)
{
struct n_tty_data *ldata = tty->disc_data;
size_t n, size, more, c;
size_t eol;
size_t tail;
- int ret, found = 0;
+ int found = 0;
/* N.B. avoid overrun if nr == 0 */
if (!*nr)
n_tty_trace("%s: eol:%zu found:%d n:%zu c:%zu tail:%zu more:%zu\n",
__func__, eol, found, n, c, tail, more);
- ret = tty_copy_to_user(tty, *b, tail, n);
- if (ret)
- return -EFAULT;
- *b += n;
+ tty_copy(tty, *kbp, tail, n);
+ *kbp += n;
*nr -= n;
if (found)
*/
static ssize_t n_tty_read(struct tty_struct *tty, struct file *file,
- unsigned char __user *buf, size_t nr)
+ unsigned char *kbuf, size_t nr,
+ void **cookie, unsigned long offset)
{
struct n_tty_data *ldata = tty->disc_data;
- unsigned char __user *b = buf;
+ unsigned char *kb = kbuf;
DEFINE_WAIT_FUNC(wait, woken_wake_function);
int c;
int minimum, time;
/* First test for status change. */
if (packet && tty->link->ctrl_status) {
unsigned char cs;
- if (b != buf)
+ if (kb != kbuf)
break;
spin_lock_irq(&tty->link->ctrl_lock);
cs = tty->link->ctrl_status;
tty->link->ctrl_status = 0;
spin_unlock_irq(&tty->link->ctrl_lock);
- if (put_user(cs, b)) {
- retval = -EFAULT;
- break;
- }
- b++;
+ *kb++ = cs;
nr--;
break;
}
}
if (ldata->icanon && !L_EXTPROC(tty)) {
- retval = canon_copy_from_read_buf(tty, &b, &nr);
+ retval = canon_copy_from_read_buf(tty, &kb, &nr);
if (retval)
break;
} else {
int uncopied;
/* Deal with packet mode. */
- if (packet && b == buf) {
- if (put_user(TIOCPKT_DATA, b)) {
- retval = -EFAULT;
- break;
- }
- b++;
+ if (packet && kb == kbuf) {
+ *kb++ = TIOCPKT_DATA;
nr--;
}
- uncopied = copy_from_read_buf(tty, &b, &nr);
- uncopied += copy_from_read_buf(tty, &b, &nr);
+ uncopied = copy_from_read_buf(tty, &kb, &nr);
+ uncopied += copy_from_read_buf(tty, &kb, &nr);
if (uncopied) {
retval = -EFAULT;
break;
n_tty_check_unthrottle(tty);
- if (b - buf >= minimum)
+ if (kb - kbuf >= minimum)
break;
if (time)
timeout = time;
remove_wait_queue(&tty->read_wait, &wait);
mutex_unlock(&ldata->atomic_read_lock);
- if (b - buf)
- retval = b - buf;
+ if (kb - kbuf)
+ retval = kb - kbuf;
return retval;
}
time->tv_sec = sec;
}
+/*
+ * Iterate on the ldisc ->read() function until we've gotten all
+ * the data the ldisc has for us.
+ *
+ * The "cookie" is something that the ldisc read function can fill
+ * in to let us know that there is more data to be had.
+ *
+ * We promise to continue to call the ldisc until it stops returning
+ * data or clears the cookie. The cookie may be something that the
+ * ldisc maintains state for and needs to free.
+ */
+static int iterate_tty_read(struct tty_ldisc *ld, struct tty_struct *tty, struct file *file,
+ char __user *buf, size_t count)
+{
+ int retval = 0;
+ void *cookie = NULL;
+ unsigned long offset = 0;
+ char kernel_buf[64];
+
+ do {
+ int size, uncopied;
+
+ size = count > sizeof(kernel_buf) ? sizeof(kernel_buf) : count;
+ size = ld->ops->read(tty, file, kernel_buf, size, &cookie, offset);
+ if (!size)
+ break;
+
+ /*
+ * A ldisc read error return will override any previously copied
+ * data (eg -EOVERFLOW from HDLC)
+ */
+ if (size < 0) {
+ memzero_explicit(kernel_buf, sizeof(kernel_buf));
+ return size;
+ }
+
+ uncopied = copy_to_user(buf+offset, kernel_buf, size);
+ size -= uncopied;
+ offset += size;
+ count -= size;
+
+ /*
+ * If the user copy failed, we still need to do another ->read()
+ * call if we had a cookie to let the ldisc clear up.
+ *
+ * But make sure size is zeroed.
+ */
+ if (unlikely(uncopied)) {
+ count = 0;
+ retval = -EFAULT;
+ }
+ } while (cookie);
+
+ /* We always clear tty buffer in case they contained passwords */
+ memzero_explicit(kernel_buf, sizeof(kernel_buf));
+ return offset ? offset : retval;
+}
+
+
/**
* tty_read - read method for tty device files
* @file: pointer to tty file
ld = tty_ldisc_ref_wait(tty);
if (!ld)
return hung_up_tty_read(file, buf, count, ppos);
+ i = -EIO;
if (ld->ops->read)
- i = ld->ops->read(tty, file, buf, count);
- else
- i = -EIO;
+ i = iterate_tty_read(ld, tty, file, buf, count);
tty_ldisc_deref(ld);
if (i > 0)
void (*close)(struct tty_struct *);
void (*flush_buffer)(struct tty_struct *tty);
ssize_t (*read)(struct tty_struct *tty, struct file *file,
- unsigned char __user *buf, size_t nr);
+ unsigned char *buf, size_t nr,
+ void **cookie, unsigned long offset);
ssize_t (*write)(struct tty_struct *tty, struct file *file,
const unsigned char *buf, size_t nr);
int (*ioctl)(struct tty_struct *tty, struct file *file,
/* We don't provide read/write/poll interface for user space. */
static ssize_t nci_uart_tty_read(struct tty_struct *tty, struct file *file,
- unsigned char __user *buf, size_t nr)
+ unsigned char *buf, size_t nr,
+ void **cookie, unsigned long offset)
{
return 0;
}
projects / linux-2.6-block.git / commitdiff