We want to stop abusing memory hotplug infrastructure in memtrace code
to perform allocations and remove the linear mapping. Instead we will use
alloc_contig_pages() and remove the identity mapping manually.
Let's factor out creating/removing the linear mapping into
arch_create_linear_mapping() / arch_remove_linear_mapping() - so in the
future, we might be able to have whole arch_add_memory() /
arch_remove_memory() be implemented in common code.
Cc: Michael Ellerman <m...@ellerman.id.au>
Cc: Benjamin Herrenschmidt <b...@kernel.crashing.org>
Cc: Paul Mackerras <pau...@samba.org>
Cc: Rashmica Gupta <rashmic...@gmail.com>
Cc: Andrew Morton <a...@linux-foundation.org>
Cc: Mike Rapoport <r...@kernel.org>
Cc: Michal Hocko <mho...@suse.com>
Cc: Oscar Salvador <osalva...@suse.de>
Cc: Wei Yang <richard.weiy...@linux.alibaba.com>
Signed-off-by: David Hildenbrand <da...@redhat.com>
---
arch/powerpc/mm/mem.c | 41 +++++++++++++++++++++++-----------
include/linux/memory_hotplug.h | 3 +++
2 files changed, 31 insertions(+), 13 deletions(-)
diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c
index 01ec2a252f09..8a86d81f8df0 100644
--- a/arch/powerpc/mm/mem.c
+++ b/arch/powerpc/mm/mem.c
@@ -120,34 +120,26 @@ static void flush_dcache_range_chunked(unsigned long
start, unsigned long stop,
}
}
-int __ref arch_add_memory(int nid, u64 start, u64 size,
- struct mhp_params *params)
+int __ref arch_create_linear_mapping(int nid, u64 start, u64 size,
+ struct mhp_params *params)
{
- unsigned long start_pfn = start >> PAGE_SHIFT;
- unsigned long nr_pages = size >> PAGE_SHIFT;
int rc;
start = (unsigned long)__va(start);
rc = create_section_mapping(start, start + size, nid,
params->pgprot);
if (rc) {
- pr_warn("Unable to create mapping for hot added memory
0x%llx..0x%llx: %d\n",
+ pr_warn("Unable to create linear mapping for 0x%llx..0x%llx:
%d\n",
start, start + size, rc);
return -EFAULT;
}
-
- return __add_pages(nid, start_pfn, nr_pages, params);
+ return 0;
}
-void __ref arch_remove_memory(int nid, u64 start, u64 size,
- struct vmem_altmap *altmap)
+void __ref arch_remove_linear_mapping(u64 start, u64 size)
{
- unsigned long start_pfn = start >> PAGE_SHIFT;
- unsigned long nr_pages = size >> PAGE_SHIFT;
int ret;
- __remove_pages(start_pfn, nr_pages, altmap);
-
/* Remove htab bolted mappings for this section of memory */
start = (unsigned long)__va(start);
flush_dcache_range_chunked(start, start + size, FLUSH_CHUNK_SIZE);
@@ -160,6 +152,29 @@ void __ref arch_remove_memory(int nid, u64 start, u64 size,
*/
vm_unmap_aliases();
}
+
+int __ref arch_add_memory(int nid, u64 start, u64 size,
+ struct mhp_params *params)
+{
+ unsigned long start_pfn = start >> PAGE_SHIFT;
+ unsigned long nr_pages = size >> PAGE_SHIFT;
+ int rc;
+
+ rc = arch_create_linear_mapping(nid, start, size, params);
+ if (rc)
+ return rc;
+ return __add_pages(nid, start_pfn, nr_pages, params);
+}
+
+void __ref arch_remove_memory(int nid, u64 start, u64 size,
+ struct vmem_altmap *altmap)
+{
+ unsigned long start_pfn = start >> PAGE_SHIFT;
+ unsigned long nr_pages = size >> PAGE_SHIFT;
+
+ __remove_pages(start_pfn, nr_pages, altmap);
+ arch_remove_linear_mapping(start, size);
+}
#endif
#ifndef CONFIG_NEED_MULTIPLE_NODES
diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h
index d65c6fdc5cfc..00b9e9bd3850 100644
--- a/include/linux/memory_hotplug.h
+++ b/include/linux/memory_hotplug.h
@@ -375,6 +375,9 @@ extern struct page *sparse_decode_mem_map(unsigned long
coded_mem_map,
unsigned long pnum);
extern struct zone *zone_for_pfn_range(int online_type, int nid, unsigned
start_pfn,
unsigned long nr_pages);
+extern int arch_create_linear_mapping(int nid, u64 start, u64 size,
+ struct mhp_params *params);
+void arch_remove_linear_mapping(u64 start, u64 size);
#endif /* CONFIG_MEMORY_HOTPLUG */
#endif /* __LINUX_MEMORY_HOTPLUG_H */
--
2.26.2
