| Message ID | 1410256619-3213-2-git-send-email-ankit.jindal@linaro.org |
|---|---|
| State | New |
| Headers | show |
On Tue, Sep 09, 2014 at 03:26:55PM +0530, Ankit Jindal wrote: > Currently, three types of mem regions are supported: UIO_MEM_PHYS, > UIO_MEM_LOGICAL and UIO_MEM_VIRTUAL. Among these UIO_MEM_PHYS helps > UIO driver export physcial memory to user space as non-cacheable > user memory. Typcially memory-mapped registers of a device are exported > to user space as UIO_MEM_PHYS type mem region. The UIO_MEM_PHYS type > is not useful if dma-capable devices are capable of maintaining coherency > with CPU caches becasue we can allow cacheable access to memory shared > between such devices and user space. > > This patch adds new type UIO_MEM_PHYS_CACHE for mem regions to enable > cacheable access to physical memory from user space. > > Signed-off-by: Ankit Jindal <ankit.jindal@linaro.org> > Signed-off-by: Tushar Jagad <tushar.jagad@linaro.org> > --- > drivers/uio/uio.c | 22 +++++++++++++--------- > include/linux/uio_driver.h | 7 ++++--- > 2 files changed, 17 insertions(+), 12 deletions(-) > > diff --git a/drivers/uio/uio.c b/drivers/uio/uio.c > index a673e5b..ff5b6c0 100644 > --- a/drivers/uio/uio.c > +++ b/drivers/uio/uio.c > @@ -644,7 +644,7 @@ static const struct vm_operations_struct uio_physical_vm_ops = { > #endif > }; > > -static int uio_mmap_physical(struct vm_area_struct *vma) > +static int uio_mmap_physical(struct vm_area_struct *vma, bool cacheable) > { > struct uio_device *idev = vma->vm_private_data; > int mi = uio_find_mem_index(vma); > @@ -659,7 +659,9 @@ static int uio_mmap_physical(struct vm_area_struct *vma) > return -EINVAL; > > vma->vm_ops = &uio_physical_vm_ops; > - vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); > + > + if (!cacheable) > + vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); > > /* > * We cannot use the vm_iomap_memory() helper here, > @@ -706,13 +708,15 @@ static int uio_mmap(struct file *filep, struct vm_area_struct *vma) > } > > switch (idev->info->mem[mi].memtype) { > - case UIO_MEM_PHYS: > - return uio_mmap_physical(vma); > - case UIO_MEM_LOGICAL: > - case UIO_MEM_VIRTUAL: > - return uio_mmap_logical(vma); > - default: > - return -EINVAL; > + case UIO_MEM_PHYS: > + return uio_mmap_physical(vma, false); > + case UIO_MEM_LOGICAL: > + case UIO_MEM_VIRTUAL: > + return uio_mmap_logical(vma); > + case UIO_MEM_PHYS_CACHE: > + return uio_mmap_physical(vma, true); > + default: > + return -EINVAL; Please don't do code style cleanups in the same patch you are adding new functionality. I can't take this because of this, sorry. greg k-h -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
On 10 September 2014 00:59, Greg Kroah-Hartman <gregkh@linuxfoundation.org> wrote: > On Tue, Sep 09, 2014 at 03:26:55PM +0530, Ankit Jindal wrote: >> Currently, three types of mem regions are supported: UIO_MEM_PHYS, >> UIO_MEM_LOGICAL and UIO_MEM_VIRTUAL. Among these UIO_MEM_PHYS helps >> UIO driver export physcial memory to user space as non-cacheable >> user memory. Typcially memory-mapped registers of a device are exported >> to user space as UIO_MEM_PHYS type mem region. The UIO_MEM_PHYS type >> is not useful if dma-capable devices are capable of maintaining coherency >> with CPU caches becasue we can allow cacheable access to memory shared >> between such devices and user space. >> >> This patch adds new type UIO_MEM_PHYS_CACHE for mem regions to enable >> cacheable access to physical memory from user space. >> >> Signed-off-by: Ankit Jindal <ankit.jindal@linaro.org> >> Signed-off-by: Tushar Jagad <tushar.jagad@linaro.org> >> --- >> drivers/uio/uio.c | 22 +++++++++++++--------- >> include/linux/uio_driver.h | 7 ++++--- >> 2 files changed, 17 insertions(+), 12 deletions(-) >> >> diff --git a/drivers/uio/uio.c b/drivers/uio/uio.c >> index a673e5b..ff5b6c0 100644 >> --- a/drivers/uio/uio.c >> +++ b/drivers/uio/uio.c >> @@ -644,7 +644,7 @@ static const struct vm_operations_struct uio_physical_vm_ops = { >> #endif >> }; >> >> -static int uio_mmap_physical(struct vm_area_struct *vma) >> +static int uio_mmap_physical(struct vm_area_struct *vma, bool cacheable) >> { >> struct uio_device *idev = vma->vm_private_data; >> int mi = uio_find_mem_index(vma); >> @@ -659,7 +659,9 @@ static int uio_mmap_physical(struct vm_area_struct *vma) >> return -EINVAL; >> >> vma->vm_ops = &uio_physical_vm_ops; >> - vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); >> + >> + if (!cacheable) >> + vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); >> >> /* >> * We cannot use the vm_iomap_memory() helper here, >> @@ -706,13 +708,15 @@ static int uio_mmap(struct file *filep, struct vm_area_struct *vma) >> } >> >> switch (idev->info->mem[mi].memtype) { >> - case UIO_MEM_PHYS: >> - return uio_mmap_physical(vma); >> - case UIO_MEM_LOGICAL: >> - case UIO_MEM_VIRTUAL: >> - return uio_mmap_logical(vma); >> - default: >> - return -EINVAL; >> + case UIO_MEM_PHYS: >> + return uio_mmap_physical(vma, false); >> + case UIO_MEM_LOGICAL: >> + case UIO_MEM_VIRTUAL: >> + return uio_mmap_logical(vma); >> + case UIO_MEM_PHYS_CACHE: >> + return uio_mmap_physical(vma, true); >> + default: >> + return -EINVAL; > > Please don't do code style cleanups in the same patch you are adding new > functionality. I can't take this because of this, sorry. Sure, I will separate out the patch for code style cleanups. > > greg k-h Thanks, Ankit -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
diff --git a/drivers/uio/uio.c b/drivers/uio/uio.c index a673e5b..ff5b6c0 100644 --- a/drivers/uio/uio.c +++ b/drivers/uio/uio.c @@ -644,7 +644,7 @@ static const struct vm_operations_struct uio_physical_vm_ops = { #endif }; -static int uio_mmap_physical(struct vm_area_struct *vma) +static int uio_mmap_physical(struct vm_area_struct *vma, bool cacheable) { struct uio_device *idev = vma->vm_private_data; int mi = uio_find_mem_index(vma); @@ -659,7 +659,9 @@ static int uio_mmap_physical(struct vm_area_struct *vma) return -EINVAL; vma->vm_ops = &uio_physical_vm_ops; - vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); + + if (!cacheable) + vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); /* * We cannot use the vm_iomap_memory() helper here, @@ -706,13 +708,15 @@ static int uio_mmap(struct file *filep, struct vm_area_struct *vma) } switch (idev->info->mem[mi].memtype) { - case UIO_MEM_PHYS: - return uio_mmap_physical(vma); - case UIO_MEM_LOGICAL: - case UIO_MEM_VIRTUAL: - return uio_mmap_logical(vma); - default: - return -EINVAL; + case UIO_MEM_PHYS: + return uio_mmap_physical(vma, false); + case UIO_MEM_LOGICAL: + case UIO_MEM_VIRTUAL: + return uio_mmap_logical(vma); + case UIO_MEM_PHYS_CACHE: + return uio_mmap_physical(vma, true); + default: + return -EINVAL; } } diff --git a/include/linux/uio_driver.h b/include/linux/uio_driver.h index 1ad4724..f6ea5bc 100644 --- a/include/linux/uio_driver.h +++ b/include/linux/uio_driver.h @@ -114,10 +114,11 @@ extern void uio_event_notify(struct uio_info *info); #define UIO_IRQ_NONE 0 /* defines for uio_mem->memtype */ -#define UIO_MEM_NONE 0 -#define UIO_MEM_PHYS 1 +#define UIO_MEM_NONE 0 +#define UIO_MEM_PHYS 1 #define UIO_MEM_LOGICAL 2 -#define UIO_MEM_VIRTUAL 3 +#define UIO_MEM_VIRTUAL 3 +#define UIO_MEM_PHYS_CACHE 4 /* defines for uio_port->porttype */ #define UIO_PORT_NONE 0