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| author | Alex Sierra <alex.sierra@amd.com> | 2022-07-15 17:05:10 +0200 |
|---|---|---|
| committer | akpm <akpm@linux-foundation.org> | 2022-07-18 02:14:27 +0200 |
| commit | f25cbb7a95a24ff9a2a3bebd308e303942ae6b2c (patch) | |
| tree | 71792ded12c877bb3607c65047887c254e0f0901 /mm/memremap.c | |
| parent | mm: move page zone helpers from mm.h to mmzone.h (diff) | |
| download | linux-f25cbb7a95a24ff9a2a3bebd308e303942ae6b2c.tar.xz linux-f25cbb7a95a24ff9a2a3bebd308e303942ae6b2c.zip | |
mm: add zone device coherent type memory support
Device memory that is cache coherent from device and CPU point of view.
This is used on platforms that have an advanced system bus (like CAPI or
CXL). Any page of a process can be migrated to such memory. However, no
one should be allowed to pin such memory so that it can always be evicted.
[hch@lst.de: rebased ontop of the refcount changes, remove is_dev_private_or_coherent_page]
Link: https://lkml.kernel.org/r/20220715150521.18165-4-alex.sierra@amd.com
Signed-off-by: Alex Sierra <alex.sierra@amd.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Felix Kuehling <Felix.Kuehling@amd.com>
Reviewed-by: Alistair Popple <apopple@nvidia.com>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Ralph Campbell <rcampbell@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'mm/memremap.c')
| -rw-r--r-- | mm/memremap.c | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/mm/memremap.c b/mm/memremap.c index 8b5c8fd4ea8e..f0955785150f 100644 --- a/mm/memremap.c +++ b/mm/memremap.c @@ -315,6 +315,16 @@ void *memremap_pages(struct dev_pagemap *pgmap, int nid) return ERR_PTR(-EINVAL); } break; + case MEMORY_DEVICE_COHERENT: + if (!pgmap->ops->page_free) { + WARN(1, "Missing page_free method\n"); + return ERR_PTR(-EINVAL); + } + if (!pgmap->owner) { + WARN(1, "Missing owner\n"); + return ERR_PTR(-EINVAL); + } + break; case MEMORY_DEVICE_FS_DAX: if (IS_ENABLED(CONFIG_FS_DAX_LIMITED)) { WARN(1, "File system DAX not supported\n"); |