On Thu, Oct 10, 2019 at 5:10 PM Christoph Hellwig <h...@infradead.org> wrote: > On Thu, Oct 10, 2019 at 02:06:22PM +0000, Omer Shpigelman wrote: > > This patch adds support in mapping of vmalloc memory. > > In contrary to user memory, vmalloc memory is already pinned and has > > no vm_area structure. Therefore a new capability was needed in order > > to map this memory. > > Unless I am missing something you mix user and kernel pointers in your > is_vmalloc_addr checks. That will break on those architectures that have > separate kernel and user address spaces.
The is_vmalloc_addr checks are for user pointers and for memory which was allocated by the driver with vmalloc_user. > > > Mapping vmalloc memory is needed for Gaudi ASIC. > > How does that ASIC pass in the vmalloc memory? I don't fully understand > the code, but it seems like the addresses are fed from ioctl, which means > they only come from userspace. The user pointers are indeed fed from ioctl for DMA purpose, but as I wrote above the vmalloc memory is allocated by the driver with vmalloc_user which will be mmapped later on in order to create a shared buffer between the driver and the userspace process.
