From: Alex Sierra <alex.sierra@amd.com>
Date: Fri, 15 Jul 2022 10:05:08 -0500
Subject: mm: rename is_pinnable_page() to is_longterm_pinnable_page()
Git-commit: 6077c943beee407168f72ece745b0aeaef6b896f
Patch-mainline: v6.0-rc1
References: jsc#PED-1294

[ SLE15-SP5 backport: omit the missing folio parts ]

Patch series "Add MEMORY_DEVICE_COHERENT for coherent device memory
mapping", v9.

This patch series introduces MEMORY_DEVICE_COHERENT, a type of memory
owned by a device that can be mapped into CPU page tables like
MEMORY_DEVICE_GENERIC and can also be migrated like MEMORY_DEVICE_PRIVATE.

This patch series is mostly self-contained except for a few places where
it needs to update other subsystems to handle the new memory type.

System stability and performance are not affected according to our ongoing
testing, including xfstests.

How it works: The system BIOS advertises the GPU device memory (aka VRAM)
as SPM (special purpose memory) in the UEFI system address map.

The amdgpu driver registers the memory with devmap as
MEMORY_DEVICE_COHERENT using devm_memremap_pages.  The initial user for
this hardware page migration capability is the Frontier supercomputer
project.  This functionality is not AMD-specific.  We expect other GPU
vendors to find this functionality useful, and possibly other hardware
types in the future.

Our test nodes in the lab are similar to the Frontier configuration, with
.5 TB of system memory plus 256 GB of device memory split across 4 GPUs,
all in a single coherent address space.  Page migration is expected to
improve application efficiency significantly.  We will report empirical
results as they become available.

Coherent device type pages at gup are now migrated back to system memory
if they are being pinned long-term (FOLL_LONGTERM).  The reason is, that
long-term pinning would interfere with the device memory manager owning
the device-coherent pages (e.g.  evictions in TTM).  These series
incorporate Alistair Popple patches to do this migration from
pin_user_pages() calls.  hmm_gup_test has been added to hmm-test to test
different get user pages calls.

This series includes handling of device-managed anonymous pages returned
by vm_normal_pages.  Although they behave like normal pages for purposes
of mapping in CPU page tables and for COW, they do not support LRU lists,
NUMA migration or THP.

We also introduced a FOLL_LRU flag that adds the same behaviour to
follow_page and related APIs, to allow callers to specify that they expect
to put pages on an LRU list.


This patch (of 14):

is_pinnable_page() and folio_is_pinnable() are renamed to
is_longterm_pinnable_page() and folio_is_longterm_pinnable() respectively.
These functions are used in the FOLL_LONGTERM flag context.

Link: https://lkml.kernel.org/r/20220715150521.18165-1-alex.sierra@amd.com
Link: https://lkml.kernel.org/r/20220715150521.18165-2-alex.sierra@amd.com
Signed-off-by: Alex Sierra <alex.sierra@amd.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Felix Kuehling <Felix.Kuehling@amd.com>
Cc: Ralph Campbell <rcampbell@nvidia.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
---
 include/linux/mm.h |    4 ++--
 mm/gup.c           |    4 ++--
 mm/gup_test.c      |    2 +-
 mm/hugetlb.c       |    2 +-
 4 files changed, 6 insertions(+), 6 deletions(-)

--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -1525,7 +1525,7 @@ static inline unsigned long page_to_sect
 
 /* MIGRATE_CMA and ZONE_MOVABLE do not allow pin pages */
 #ifdef CONFIG_MIGRATION
-static inline bool is_pinnable_page(struct page *page)
+static inline bool is_longterm_pinnable_page(struct page *page)
 {
 #ifdef CONFIG_CMA
 	int mt = get_pageblock_migratetype(page);
@@ -1536,7 +1536,7 @@ static inline bool is_pinnable_page(stru
 	return !is_zone_movable_page(page) || is_zero_pfn(page_to_pfn(page));
 }
 #else
-static inline bool is_pinnable_page(struct page *page)
+static inline bool is_longterm_pinnable_page(struct page *page)
 {
 	return true;
 }
--- a/mm/gup.c
+++ b/mm/gup.c
@@ -136,7 +136,7 @@ __maybe_unused struct page *try_grab_com
 		 * path.
 		 */
 		if (unlikely((flags & FOLL_LONGTERM) &&
-			     !is_pinnable_page(page)))
+			     !is_longterm_pinnable_page(page)))
 			return NULL;
 
 		/*
@@ -1838,7 +1838,7 @@ static long check_and_migrate_movable_pa
 			continue;
 		prev_head = head;
 
-		if (is_pinnable_page(head))
+		if (is_longterm_pinnable_page(head))
 			continue;
 
 		/*
--- a/mm/gup_test.c
+++ b/mm/gup_test.c
@@ -53,7 +53,7 @@ static void verify_dma_pinned(unsigned i
 				dump_page(page, "gup_test failure");
 				break;
 			} else if (cmd == PIN_LONGTERM_BENCHMARK &&
-				WARN(!is_pinnable_page(page),
+				WARN(!is_longterm_pinnable_page(page),
 				     "pages[%lu] is NOT pinnable but pinned\n",
 				     i)) {
 				dump_page(page, "gup_test failure");
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -1087,7 +1087,7 @@ static struct page *dequeue_huge_page_no
 
 	lockdep_assert_held(&hugetlb_lock);
 	list_for_each_entry(page, &h->hugepage_freelists[nid], lru) {
-		if (pin && !is_pinnable_page(page))
+		if (pin && !is_longterm_pinnable_page(page))
 			continue;
 
 		if (PageHWPoison(page))