Re: [patch 1/1] Convert drivers in drivers/char/drm to use.unlocked_ioctl
From: Dave Airlie
Date: Tue Jan 08 2008 - 22:38:07 EST
> The drm drivers in this patch all used drm_ioctl to perform their
> ioctl calls. The common function is converted to use lock_kernel()
> and unlock_kernel() and the drivers are converted to use .unlocked_ioctl
>
NAK
I've started looking at this already in the drm git tree, I'm going to
provide both locked and unlocked paths for drivers to choose, as we need
to audit the drivers on a per-driver basis, the other option is to provide
wrappers in each driver to do the lock/unlock kernel and leave drm_ioctl
alone..
I'll take a look kmalloc failure case sounds like a bug though..
Dave.
> Signed-off-by: Kevin Winchester <kjwinchester@xxxxxxxxx>
>
> ---
>
> I also noted that in the failed kmalloc case in drm_ioctl(), the function
> immediately returns -ENOMEM, rather than following the error path that
> calls atomic_dec(&dev->ioctl_count);. I'm not sure if the ioctl_count
> is just not important in the -ENOMEM case, or if this is a bug.
>
> drivers/char/drm/drmP.h | 3 +--
> drivers/char/drm/drm_drv.c | 10 ++++++----
> drivers/char/drm/i810_dma.c | 2 +-
> drivers/char/drm/i810_drv.c | 2 +-
> drivers/char/drm/i830_dma.c | 2 +-
> drivers/char/drm/i830_drv.c | 2 +-
> drivers/char/drm/i915_drv.c | 2 +-
> drivers/char/drm/mga_drv.c | 2 +-
> drivers/char/drm/r128_drv.c | 2 +-
> drivers/char/drm/radeon_drv.c | 2 +-
> drivers/char/drm/savage_drv.c | 2 +-
> drivers/char/drm/sis_drv.c | 2 +-
> drivers/char/drm/tdfx_drv.c | 2 +-
> drivers/char/drm/via_drv.c | 2 +-
> 14 files changed, 19 insertions(+), 18 deletions(-)
>
> Index: v2.6.24-rc7/drivers/char/drm/drmP.h
> ===================================================================
> --- v2.6.24-rc7.orig/drivers/char/drm/drmP.h
> +++ v2.6.24-rc7/drivers/char/drm/drmP.h
> @@ -833,8 +833,7 @@ static inline int drm_mtrr_del(int handl
> /* Driver support (drm_drv.h) */
> extern int drm_init(struct drm_driver *driver);
> extern void drm_exit(struct drm_driver *driver);
> -extern int drm_ioctl(struct inode *inode, struct file *filp,
> - unsigned int cmd, unsigned long arg);
> +extern long drm_ioctl(struct file *filp, unsigned int cmd, unsigned long arg);
> extern long drm_compat_ioctl(struct file *filp,
> unsigned int cmd, unsigned long arg);
> extern int drm_lastclose(struct drm_device *dev);
> Index: v2.6.24-rc7/drivers/char/drm/drm_drv.c
> ===================================================================
> --- v2.6.24-rc7.orig/drivers/char/drm/drm_drv.c
> +++ v2.6.24-rc7/drivers/char/drm/drm_drv.c
> @@ -438,7 +438,6 @@ static int drm_version(struct drm_device
> /**
> * Called whenever a process performs an ioctl on /dev/drm.
> *
> - * \param inode device inode.
> * \param file_priv DRM file private.
> * \param cmd command.
> * \param arg user argument.
> @@ -447,8 +446,7 @@ static int drm_version(struct drm_device
> * Looks up the ioctl function in the ::ioctls table, checking for root
> * previleges if so required, and dispatches to the respective function.
> */
> -int drm_ioctl(struct inode *inode, struct file *filp,
> - unsigned int cmd, unsigned long arg)
> +long drm_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
> {
> struct drm_file *file_priv = filp->private_data;
> struct drm_device *dev = file_priv->head->dev;
> @@ -458,6 +456,7 @@ int drm_ioctl(struct inode *inode, struc
> int retcode = -EINVAL;
> char *kdata = NULL;
>
> + lock_kernel();
> atomic_inc(&dev->ioctl_count);
> atomic_inc(&dev->counts[_DRM_STAT_IOCTLS]);
> ++file_priv->ioctl_count;
> @@ -494,8 +493,10 @@ int drm_ioctl(struct inode *inode, struc
> } else {
> if (cmd & (IOC_IN | IOC_OUT)) {
> kdata = kmalloc(_IOC_SIZE(cmd), GFP_KERNEL);
> - if (!kdata)
> + if (!kdata) {
> + unlock_kernel();
> return -ENOMEM;
> + }
> }
>
> if (cmd & IOC_IN) {
> @@ -520,6 +521,7 @@ int drm_ioctl(struct inode *inode, struc
> atomic_dec(&dev->ioctl_count);
> if (retcode)
> DRM_DEBUG("ret = %x\n", retcode);
> + unlock_kernel();
> return retcode;
> }
>
> Index: v2.6.24-rc7/drivers/char/drm/i810_dma.c
> ===================================================================
> --- v2.6.24-rc7.orig/drivers/char/drm/i810_dma.c
> +++ v2.6.24-rc7/drivers/char/drm/i810_dma.c
> @@ -115,7 +115,7 @@ static int i810_mmap_buffers(struct file
> static const struct file_operations i810_buffer_fops = {
> .open = drm_open,
> .release = drm_release,
> - .ioctl = drm_ioctl,
> + .unlocked_ioctl = drm_ioctl,
> .mmap = i810_mmap_buffers,
> .fasync = drm_fasync,
> };
> Index: v2.6.24-rc7/drivers/char/drm/i810_drv.c
> ===================================================================
> --- v2.6.24-rc7.orig/drivers/char/drm/i810_drv.c
> +++ v2.6.24-rc7/drivers/char/drm/i810_drv.c
> @@ -59,7 +59,7 @@ static struct drm_driver driver = {
> .owner = THIS_MODULE,
> .open = drm_open,
> .release = drm_release,
> - .ioctl = drm_ioctl,
> + .unlocked_ioctl = drm_ioctl,
> .mmap = drm_mmap,
> .poll = drm_poll,
> .fasync = drm_fasync,
> Index: v2.6.24-rc7/drivers/char/drm/i830_dma.c
> ===================================================================
> --- v2.6.24-rc7.orig/drivers/char/drm/i830_dma.c
> +++ v2.6.24-rc7/drivers/char/drm/i830_dma.c
> @@ -117,7 +117,7 @@ static int i830_mmap_buffers(struct file
> static const struct file_operations i830_buffer_fops = {
> .open = drm_open,
> .release = drm_release,
> - .ioctl = drm_ioctl,
> + .unlocked_ioctl = drm_ioctl,
> .mmap = i830_mmap_buffers,
> .fasync = drm_fasync,
> };
> Index: v2.6.24-rc7/drivers/char/drm/i830_drv.c
> ===================================================================
> --- v2.6.24-rc7.orig/drivers/char/drm/i830_drv.c
> +++ v2.6.24-rc7/drivers/char/drm/i830_drv.c
> @@ -70,7 +70,7 @@ static struct drm_driver driver = {
> .owner = THIS_MODULE,
> .open = drm_open,
> .release = drm_release,
> - .ioctl = drm_ioctl,
> + .unlocked_ioctl = drm_ioctl,
> .mmap = drm_mmap,
> .poll = drm_poll,
> .fasync = drm_fasync,
> Index: v2.6.24-rc7/drivers/char/drm/i915_drv.c
> ===================================================================
> --- v2.6.24-rc7.orig/drivers/char/drm/i915_drv.c
> +++ v2.6.24-rc7/drivers/char/drm/i915_drv.c
> @@ -64,7 +64,7 @@ static struct drm_driver driver = {
> .owner = THIS_MODULE,
> .open = drm_open,
> .release = drm_release,
> - .ioctl = drm_ioctl,
> + .unlocked_ioctl = drm_ioctl,
> .mmap = drm_mmap,
> .poll = drm_poll,
> .fasync = drm_fasync,
> Index: v2.6.24-rc7/drivers/char/drm/mga_drv.c
> ===================================================================
> --- v2.6.24-rc7.orig/drivers/char/drm/mga_drv.c
> +++ v2.6.24-rc7/drivers/char/drm/mga_drv.c
> @@ -67,7 +67,7 @@ static struct drm_driver driver = {
> .owner = THIS_MODULE,
> .open = drm_open,
> .release = drm_release,
> - .ioctl = drm_ioctl,
> + .unlocked_ioctl = drm_ioctl,
> .mmap = drm_mmap,
> .poll = drm_poll,
> .fasync = drm_fasync,
> Index: v2.6.24-rc7/drivers/char/drm/r128_drv.c
> ===================================================================
> --- v2.6.24-rc7.orig/drivers/char/drm/r128_drv.c
> +++ v2.6.24-rc7/drivers/char/drm/r128_drv.c
> @@ -62,7 +62,7 @@ static struct drm_driver driver = {
> .owner = THIS_MODULE,
> .open = drm_open,
> .release = drm_release,
> - .ioctl = drm_ioctl,
> + .unlocked_ioctl = drm_ioctl,
> .mmap = drm_mmap,
> .poll = drm_poll,
> .fasync = drm_fasync,
> Index: v2.6.24-rc7/drivers/char/drm/radeon_drv.c
> ===================================================================
> --- v2.6.24-rc7.orig/drivers/char/drm/radeon_drv.c
> +++ v2.6.24-rc7/drivers/char/drm/radeon_drv.c
> @@ -85,7 +85,7 @@ static struct drm_driver driver = {
> .owner = THIS_MODULE,
> .open = drm_open,
> .release = drm_release,
> - .ioctl = drm_ioctl,
> + .unlocked_ioctl = drm_ioctl,
> .mmap = drm_mmap,
> .poll = drm_poll,
> .fasync = drm_fasync,
> Index: v2.6.24-rc7/drivers/char/drm/savage_drv.c
> ===================================================================
> --- v2.6.24-rc7.orig/drivers/char/drm/savage_drv.c
> +++ v2.6.24-rc7/drivers/char/drm/savage_drv.c
> @@ -50,7 +50,7 @@ static struct drm_driver driver = {
> .owner = THIS_MODULE,
> .open = drm_open,
> .release = drm_release,
> - .ioctl = drm_ioctl,
> + .unlocked_ioctl = drm_ioctl,
> .mmap = drm_mmap,
> .poll = drm_poll,
> .fasync = drm_fasync,
> Index: v2.6.24-rc7/drivers/char/drm/sis_drv.c
> ===================================================================
> --- v2.6.24-rc7.orig/drivers/char/drm/sis_drv.c
> +++ v2.6.24-rc7/drivers/char/drm/sis_drv.c
> @@ -80,7 +80,7 @@ static struct drm_driver driver = {
> .owner = THIS_MODULE,
> .open = drm_open,
> .release = drm_release,
> - .ioctl = drm_ioctl,
> + .unlocked_ioctl = drm_ioctl,
> .mmap = drm_mmap,
> .poll = drm_poll,
> .fasync = drm_fasync,
> Index: v2.6.24-rc7/drivers/char/drm/tdfx_drv.c
> ===================================================================
> --- v2.6.24-rc7.orig/drivers/char/drm/tdfx_drv.c
> +++ v2.6.24-rc7/drivers/char/drm/tdfx_drv.c
> @@ -48,7 +48,7 @@ static struct drm_driver driver = {
> .owner = THIS_MODULE,
> .open = drm_open,
> .release = drm_release,
> - .ioctl = drm_ioctl,
> + .unlocked_ioctl = drm_ioctl,
> .mmap = drm_mmap,
> .poll = drm_poll,
> .fasync = drm_fasync,
> Index: v2.6.24-rc7/drivers/char/drm/via_drv.c
> ===================================================================
> --- v2.6.24-rc7.orig/drivers/char/drm/via_drv.c
> +++ v2.6.24-rc7/drivers/char/drm/via_drv.c
> @@ -62,7 +62,7 @@ static struct drm_driver driver = {
> .owner = THIS_MODULE,
> .open = drm_open,
> .release = drm_release,
> - .ioctl = drm_ioctl,
> + .unlocked_ioctl = drm_ioctl,
> .mmap = drm_mmap,
> .poll = drm_poll,
> .fasync = drm_fasync,
>
>
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