From d9cbe09d39aa13f6924dc5fb88325de7ef01a72e Mon Sep 17 00:00:00 2001 From: Dan Williams Date: Thu, 3 Mar 2016 09:14:36 -0800 Subject: [PATCH] libnvdimm, pmem: fix 'pfn' support for section-misaligned namespaces 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 --- drivers/nvdimm/pfn.h | 13 +++++++++++++ drivers/nvdimm/pmem.c | 24 ++++++++++++++++++++++-- 2 files changed, 35 insertions(+), 2 deletions(-) diff --git a/drivers/nvdimm/pfn.h b/drivers/nvdimm/pfn.h index cc24375..6ee707e 100644 --- a/drivers/nvdimm/pfn.h +++ b/drivers/nvdimm/pfn.h @@ -15,6 +15,7 @@ #define __NVDIMM_PFN_H #include +#include #define PFN_SIG_LEN 16 #define PFN_SIG "NVDIMM_PFN_INFO\0" @@ -32,4 +33,16 @@ struct nd_pfn_sb { u8 padding[4012]; __le64 checksum; }; + +#ifdef CONFIG_SPARSEMEM +#define PFN_SECTION_ALIGN_DOWN(x) SECTION_ALIGN_DOWN(x) +#define PFN_SECTION_ALIGN_UP(x) SECTION_ALIGN_UP(x) +#else +/* + * In this case ZONE_DEVICE=n and we will disable 'pfn' device support, + * but we still want pmem to compile. + */ +#define PFN_SECTION_ALIGN_DOWN(x) (x) +#define PFN_SECTION_ALIGN_UP(x) (x) +#endif #endif /* __NVDIMM_PFN_H */ diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c index 8d0b546..59d568a 100644 --- a/drivers/nvdimm/pmem.c +++ b/drivers/nvdimm/pmem.c @@ -356,6 +356,26 @@ 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); + + return PFN_SECTION_ALIGN_DOWN(base_pfn); +} + +static unsigned long init_altmap_reserve(resource_size_t base) +{ + unsigned long reserve = __phys_to_pfn(SZ_8K); + unsigned long base_pfn = __phys_to_pfn(base); + + reserve += base_pfn - PFN_SECTION_ALIGN_DOWN(base_pfn); + 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 +389,8 @@ 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) -- 2.7.4