The altmap for a section-misaligned namespace needs to arrange for the
base_pfn to be section-aligned. As a result the 'reserve' region (pfns
from base that do not have a struct page) must be increased. Otherwise
we trip the altmap validation check in __add_pages:
if (altmap->base_pfn != phys_start_pfn
|| vmem_altmap_offset(altmap) > nr_pages) {
pr_warn_once("memory add fail, invalid altmap\n");
return -EINVAL;
}
Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx>
---
drivers/nvdimm/pmem.c | 29 +++++++++++++++++++++++++++--
1 file changed, 27 insertions(+), 2 deletions(-)
diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c
index efc2a5e671c6..6a6283ab974c 100644
--- a/drivers/nvdimm/pmem.c
+++ b/drivers/nvdimm/pmem.c
@@ -356,6 +356,31 @@ static int nvdimm_namespace_detach_pfn(struct nd_namespace_common *ndns)
return 0;
}
+/*
+ * We hotplug memory at section granularity, pad the reserved area from
+ * the previous section base to the namespace base address.
+ */
+static unsigned long init_altmap_base(resource_size_t base)
+{
+ unsigned long base_pfn = __phys_to_pfn(base);
+
+#ifdef CONFIG_SPARSEMEM
+ base_pfn = SECTION_ALIGN_DOWN(base_pfn);
+#endif
+ return base_pfn;
+}
+
+static unsigned long init_altmap_reserve(resource_size_t base)
+{
+ unsigned long base_pfn = __phys_to_pfn(base);
+ unsigned long reserve = __phys_to_pfn(SZ_8K);
+
+#ifdef CONFIG_SPARSEMEM
+ reserve += base_pfn - SECTION_ALIGN_DOWN(base_pfn);
+#endif
+ return reserve;
+}
+
static int nvdimm_namespace_attach_pfn(struct nd_namespace_common *ndns)
{
struct nd_namespace_io *nsio = to_nd_namespace_io(&ndns->dev);
@@ -369,8 +394,8 @@ static int nvdimm_namespace_attach_pfn(struct nd_namespace_common *ndns)
phys_addr_t offset;
int rc;
struct vmem_altmap __altmap = {
- .base_pfn = __phys_to_pfn(nsio->res.start),
- .reserve = __phys_to_pfn(SZ_8K),
+ .base_pfn = init_altmap_base(nsio->res.start),
+ .reserve = init_altmap_reserve(nsio->res.start),
};
if (!nd_pfn->uuid || !nd_pfn->ndns)
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@xxxxxxxxx. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>