Documentation/vm/memory-model.rst

1 .. SPDX-License-Identifier: GPL-2.0
29 Regardless of the selected memory model, there exists one-to-one
41 non-NUMA systems with contiguous, or mostly contiguous, physical
60 straightforward: `PFN - ARCH_PFN_OFFSET` is an index to the
82 Every `node_mem_map` behaves exactly as FLATMEM's `mem_map` -
96 page->flags.
106 SPARSEMEM is the most versatile memory model available in Linux and it
108 as hot-plug and hot-remove of the physical memory, alternative memory
109 maps for non-volatile memory devices and deferred initialization of
128    NR\_MEM\_SECTIONS = 2 ^ {(MAX\_PHYSMEM\_BITS - SECTION\_SIZE\_BITS)}
130 The `mem_section` objects are arranged in a two-dimensional array
147 corresponding `struct page` - a "classic sparse" and "sparse
151 The classic sparse encodes the section number of a page in page->flags
173 for persistent memory devices in pre-allocated storage on those
201 this lack of user-api constraint to allow sub-section sized memory
202 ranges to be specified to :c:func:`arch_add_memory`, the top-half of
203 memory hotplug. Sub-section support allows for 2MB as the cross-arch
208 * pmem: Map platform persistent memory to be used as a direct-I/O target
211 * hmm: Extend `ZONE_DEVICE` with `->page_fault()` and `->page_free()`
212   event callbacks to allow a device-driver to coordinate memory management
213   events related to device-memory, typically GPU memory. See
217   PCI/-E topology to coordinate direct-DMA operations between themselves,