diff options
Diffstat (limited to 'drivers/spi/spidev.c')
| -rw-r--r-- | drivers/spi/spidev.c | 125 |
1 files changed, 97 insertions, 28 deletions
diff --git a/drivers/spi/spidev.c b/drivers/spi/spidev.c index 6941e04afb8..4eb7a980e67 100644 --- a/drivers/spi/spidev.c +++ b/drivers/spi/spidev.c @@ -14,10 +14,6 @@ * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ #include <linux/init.h> @@ -317,6 +313,37 @@ done: return status; } +static struct spi_ioc_transfer * +spidev_get_ioc_message(unsigned int cmd, struct spi_ioc_transfer __user *u_ioc, + unsigned *n_ioc) +{ + struct spi_ioc_transfer *ioc; + u32 tmp; + + /* Check type, command number and direction */ + if (_IOC_TYPE(cmd) != SPI_IOC_MAGIC + || _IOC_NR(cmd) != _IOC_NR(SPI_IOC_MESSAGE(0)) + || _IOC_DIR(cmd) != _IOC_WRITE) + return ERR_PTR(-ENOTTY); + + tmp = _IOC_SIZE(cmd); + if ((tmp % sizeof(struct spi_ioc_transfer)) != 0) + return ERR_PTR(-EINVAL); + *n_ioc = tmp / sizeof(struct spi_ioc_transfer); + if (*n_ioc == 0) + return NULL; + + /* copy into scratch area */ + ioc = kmalloc(tmp, GFP_KERNEL); + if (!ioc) + return ERR_PTR(-ENOMEM); + if (__copy_from_user(ioc, u_ioc, tmp)) { + kfree(ioc); + return ERR_PTR(-EFAULT); + } + return ioc; +} + static long spidev_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) { @@ -456,32 +483,15 @@ spidev_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) default: /* segmented and/or full-duplex I/O request */ - if (_IOC_NR(cmd) != _IOC_NR(SPI_IOC_MESSAGE(0)) - || _IOC_DIR(cmd) != _IOC_WRITE) { - retval = -ENOTTY; - break; - } - - tmp = _IOC_SIZE(cmd); - if ((tmp % sizeof(struct spi_ioc_transfer)) != 0) { - retval = -EINVAL; - break; - } - n_ioc = tmp / sizeof(struct spi_ioc_transfer); - if (n_ioc == 0) - break; - - /* copy into scratch area */ - ioc = kmalloc(tmp, GFP_KERNEL); - if (!ioc) { - retval = -ENOMEM; - break; - } - if (__copy_from_user(ioc, (void __user *)arg, tmp)) { - kfree(ioc); - retval = -EFAULT; + /* Check message and copy into scratch area */ + ioc = spidev_get_ioc_message(cmd, + (struct spi_ioc_transfer __user *)arg, &n_ioc); + if (IS_ERR(ioc)) { + retval = PTR_ERR(ioc); break; } + if (!ioc) + break; /* n_ioc is also 0 */ /* translate to spi_message, execute */ retval = spidev_message(spidev, ioc, n_ioc); @@ -496,8 +506,67 @@ spidev_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) #ifdef CONFIG_COMPAT static long +spidev_compat_ioc_message(struct file *filp, unsigned int cmd, + unsigned long arg) +{ + struct spi_ioc_transfer __user *u_ioc; + int retval = 0; + struct spidev_data *spidev; + struct spi_device *spi; + unsigned n_ioc, n; + struct spi_ioc_transfer *ioc; + + u_ioc = (struct spi_ioc_transfer __user *) compat_ptr(arg); + if (!access_ok(VERIFY_READ, u_ioc, _IOC_SIZE(cmd))) + return -EFAULT; + + /* guard against device removal before, or while, + * we issue this ioctl. + */ + spidev = filp->private_data; + spin_lock_irq(&spidev->spi_lock); + spi = spi_dev_get(spidev->spi); + spin_unlock_irq(&spidev->spi_lock); + + if (spi == NULL) + return -ESHUTDOWN; + + /* SPI_IOC_MESSAGE needs the buffer locked "normally" */ + mutex_lock(&spidev->buf_lock); + + /* Check message and copy into scratch area */ + ioc = spidev_get_ioc_message(cmd, u_ioc, &n_ioc); + if (IS_ERR(ioc)) { + retval = PTR_ERR(ioc); + goto done; + } + if (!ioc) + goto done; /* n_ioc is also 0 */ + + /* Convert buffer pointers */ + for (n = 0; n < n_ioc; n++) { + ioc[n].rx_buf = (uintptr_t) compat_ptr(ioc[n].rx_buf); + ioc[n].tx_buf = (uintptr_t) compat_ptr(ioc[n].tx_buf); + } + + /* translate to spi_message, execute */ + retval = spidev_message(spidev, ioc, n_ioc); + kfree(ioc); + +done: + mutex_unlock(&spidev->buf_lock); + spi_dev_put(spi); + return retval; +} + +static long spidev_compat_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) { + if (_IOC_TYPE(cmd) == SPI_IOC_MAGIC + && _IOC_NR(cmd) == _IOC_NR(SPI_IOC_MESSAGE(0)) + && _IOC_DIR(cmd) == _IOC_WRITE) + return spidev_compat_ioc_message(filp, cmd, arg); + return spidev_ioctl(filp, cmd, (unsigned long)compat_ptr(arg)); } #else |