Re: [PATCH] x86 get_unmapped_area: Add PMD alignment for DAX PMD mmap

2016-04-07 Thread Toshi Kani
On Thu, 2016-04-07 at 13:41 -0400, Matthew Wilcox wrote: > On Wed, Apr 06, 2016 at 11:44:32AM -0600, Toshi Kani wrote: > > > > > > The NVML chooses appropriate addresses and gets a properly aligned > > > address without any kernel code. > > > > An application like NVML can continue to specify a

Re: [PATCH] x86 get_unmapped_area: Add PMD alignment for DAX PMD mmap

2016-04-07 Thread Toshi Kani
On Thu, 2016-04-07 at 13:41 -0400, Matthew Wilcox wrote: > On Wed, Apr 06, 2016 at 11:44:32AM -0600, Toshi Kani wrote: > > > > > > The NVML chooses appropriate addresses and gets a properly aligned > > > address without any kernel code. > > > > An application like NVML can continue to specify a

Re: [PATCH] x86 get_unmapped_area: Add PMD alignment for DAX PMD mmap

2016-04-07 Thread Matthew Wilcox
On Wed, Apr 06, 2016 at 11:44:32AM -0600, Toshi Kani wrote: > > The NVML chooses appropriate addresses and gets a properly aligned > > address without any kernel code. > > An application like NVML can continue to specify a specific address to > mmap().  Most existing applications, however, do not

Re: [PATCH] x86 get_unmapped_area: Add PMD alignment for DAX PMD mmap

2016-04-07 Thread Matthew Wilcox
On Wed, Apr 06, 2016 at 11:44:32AM -0600, Toshi Kani wrote: > > The NVML chooses appropriate addresses and gets a properly aligned > > address without any kernel code. > > An application like NVML can continue to specify a specific address to > mmap().  Most existing applications, however, do not

Re: [PATCH] x86 get_unmapped_area: Add PMD alignment for DAX PMD mmap

2016-04-06 Thread Toshi Kani
On Wed, 2016-04-06 at 12:50 -0400, Matthew Wilcox wrote: > On Wed, Apr 06, 2016 at 07:58:09AM -0600, Toshi Kani wrote: > > > > When CONFIG_FS_DAX_PMD is set, DAX supports mmap() using PMD page > > size.  This feature relies on both mmap virtual address and FS > > block data (i.e. physical

Re: [PATCH] x86 get_unmapped_area: Add PMD alignment for DAX PMD mmap

2016-04-06 Thread Toshi Kani
On Wed, 2016-04-06 at 12:50 -0400, Matthew Wilcox wrote: > On Wed, Apr 06, 2016 at 07:58:09AM -0600, Toshi Kani wrote: > > > > When CONFIG_FS_DAX_PMD is set, DAX supports mmap() using PMD page > > size.  This feature relies on both mmap virtual address and FS > > block data (i.e. physical

Re: [PATCH] x86 get_unmapped_area: Add PMD alignment for DAX PMD mmap

2016-04-06 Thread Matthew Wilcox
On Wed, Apr 06, 2016 at 07:58:09AM -0600, Toshi Kani wrote: > When CONFIG_FS_DAX_PMD is set, DAX supports mmap() using PMD page > size. This feature relies on both mmap virtual address and FS > block data (i.e. physical address) to be aligned by the PMD page > size. Users can use mkfs options to

Re: [PATCH] x86 get_unmapped_area: Add PMD alignment for DAX PMD mmap

2016-04-06 Thread Matthew Wilcox
On Wed, Apr 06, 2016 at 07:58:09AM -0600, Toshi Kani wrote: > When CONFIG_FS_DAX_PMD is set, DAX supports mmap() using PMD page > size. This feature relies on both mmap virtual address and FS > block data (i.e. physical address) to be aligned by the PMD page > size. Users can use mkfs options to

[PATCH] x86 get_unmapped_area: Add PMD alignment for DAX PMD mmap

2016-04-06 Thread Toshi Kani
When CONFIG_FS_DAX_PMD is set, DAX supports mmap() using PMD page size. This feature relies on both mmap virtual address and FS block data (i.e. physical address) to be aligned by the PMD page size. Users can use mkfs options to specify FS to align block allocations. However, aligning mmap()

[PATCH] x86 get_unmapped_area: Add PMD alignment for DAX PMD mmap

2016-04-06 Thread Toshi Kani
When CONFIG_FS_DAX_PMD is set, DAX supports mmap() using PMD page size. This feature relies on both mmap virtual address and FS block data (i.e. physical address) to be aligned by the PMD page size. Users can use mkfs options to specify FS to align block allocations. However, aligning mmap()