mirror of https://github.com/torvalds/linux.git
4f5f8baf73
Aside from the main CMA region, it can be useful to allow userspace to
allocate from the other CMA reserved regions.
Indeed, those regions can have specific properties that can be useful to
a specific us-case.
For example, one of them platform I've been with has ECC enabled on the
entire memory but for a specific region. Using that region to allocate
framebuffers can be particular beneficial because enabling the ECC has a
performance and memory footprint cost.
Thus, exposing these regions as heaps user-space can allocate from and
import wherever needed allows to cover that use-case.
For now, only shared-dma-pools regions with the reusable property (ie,
backed by CMA) are supported, but eventually we'll want to support other
DMA pools types.
Since we collected all the CMA regions created during boot, we can
simply iterate over all of them to create the heaps.
This has a weird interaction with the recent work on the CMA name, in
particular the backward compatibility code created by commit
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| .. | ||
| accelerators | ||
| ebpf | ||
| fwctl | ||
| gpio | ||
| ioctl | ||
| media | ||
| netlink | ||
| ELF.rst | ||
| check_exec.rst | ||
| dcdbas.rst | ||
| dma-buf-alloc-exchange.rst | ||
| dma-buf-heaps.rst | ||
| futex2.rst | ||
| index.rst | ||
| iommufd.rst | ||
| isapnp.rst | ||
| landlock.rst | ||
| lsm.rst | ||
| mfd_noexec.rst | ||
| mseal.rst | ||
| no_new_privs.rst | ||
| ntsync.rst | ||
| perf_ring_buffer.rst | ||
| seccomp_filter.rst | ||
| spec_ctrl.rst | ||
| sysfs-platform_profile.rst | ||
| tee.rst | ||
| unshare.rst | ||
| vduse.rst | ||