Similar to "libnvdimm: Fix altmap reservation size calculation" provide for a reservation of a full page worth of info block space at info-block establishment time. Typically there is already slack in the padding from honoring the default 2MB alignment, but provide for a reservation for corner case configurations that would otherwise fit. Cc: Oliver O'Halloran <oohall@xxxxxxxxx> Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx> --- drivers/nvdimm/pfn_devs.c | 20 +++++++++++++------- 1 file changed, 13 insertions(+), 7 deletions(-) diff --git a/drivers/nvdimm/pfn_devs.c b/drivers/nvdimm/pfn_devs.c index 7760c1b91853..ba74a341da5d 100644 --- a/drivers/nvdimm/pfn_devs.c +++ b/drivers/nvdimm/pfn_devs.c @@ -580,6 +580,11 @@ int nd_pfn_probe(struct device *dev, struct nd_namespace_common *ndns) } EXPORT_SYMBOL(nd_pfn_probe); +static u32 info_block_reserve(void) +{ + return ALIGN(SZ_8K, PAGE_SIZE); +} + /* * We hotplug memory at section granularity, pad the reserved area from * the previous section base to the namespace base address. @@ -593,7 +598,7 @@ static unsigned long init_altmap_base(resource_size_t base) static unsigned long init_altmap_reserve(resource_size_t base) { - unsigned long reserve = PFN_UP(SZ_8K); + unsigned long reserve = info_block_reserve() >> PAGE_SHIFT; unsigned long base_pfn = PHYS_PFN(base); reserve += base_pfn - PFN_SECTION_ALIGN_DOWN(base_pfn); @@ -608,6 +613,7 @@ static int __nvdimm_setup_pfn(struct nd_pfn *nd_pfn, struct dev_pagemap *pgmap) u64 offset = le64_to_cpu(pfn_sb->dataoff); u32 start_pad = __le32_to_cpu(pfn_sb->start_pad); u32 end_trunc = __le32_to_cpu(pfn_sb->end_trunc); + u32 reserve = info_block_reserve(); struct nd_namespace_common *ndns = nd_pfn->ndns; struct nd_namespace_io *nsio = to_nd_namespace_io(&ndns->dev); resource_size_t base = nsio->res.start + start_pad; @@ -621,7 +627,7 @@ static int __nvdimm_setup_pfn(struct nd_pfn *nd_pfn, struct dev_pagemap *pgmap) res->end -= end_trunc; if (nd_pfn->mode == PFN_MODE_RAM) { - if (offset < SZ_8K) + if (offset < reserve) return -EINVAL; nd_pfn->npfns = le64_to_cpu(pfn_sb->npfns); pgmap->altmap_valid = false; @@ -634,7 +640,7 @@ static int __nvdimm_setup_pfn(struct nd_pfn *nd_pfn, struct dev_pagemap *pgmap) le64_to_cpu(nd_pfn->pfn_sb->npfns), nd_pfn->npfns); memcpy(altmap, &__altmap, sizeof(*altmap)); - altmap->free = PHYS_PFN(offset - SZ_8K); + altmap->free = PHYS_PFN(offset - reserve); altmap->alloc = 0; pgmap->altmap_valid = true; } else @@ -687,9 +693,9 @@ static int nd_pfn_init(struct nd_pfn *nd_pfn) u32 dax_label_reserve = is_nd_dax(&nd_pfn->dev) ? SZ_128K : 0; struct nd_namespace_common *ndns = nd_pfn->ndns; struct nd_namespace_io *nsio = to_nd_namespace_io(&ndns->dev); + u32 start_pad, end_trunc, reserve = info_block_reserve(); resource_size_t start, size; struct nd_region *nd_region; - u32 start_pad, end_trunc; struct nd_pfn_sb *pfn_sb; unsigned long npfns; phys_addr_t offset; @@ -734,7 +740,7 @@ static int nd_pfn_init(struct nd_pfn *nd_pfn) */ start = nsio->res.start + start_pad; size = resource_size(&nsio->res); - npfns = PFN_SECTION_ALIGN_UP((size - start_pad - end_trunc - SZ_8K) + npfns = PFN_SECTION_ALIGN_UP((size - start_pad - end_trunc - reserve) / PAGE_SIZE); if (nd_pfn->mode == PFN_MODE_PMEM) { /* @@ -742,10 +748,10 @@ static int nd_pfn_init(struct nd_pfn *nd_pfn) * when populating the vmemmap. This *should* be equal to * PMD_SIZE for most architectures. */ - offset = ALIGN(start + SZ_8K + 64 * npfns + dax_label_reserve, + offset = ALIGN(start + reserve + 64 * npfns + dax_label_reserve, max(nd_pfn->align, PMD_SIZE)) - start; } else if (nd_pfn->mode == PFN_MODE_RAM) - offset = ALIGN(start + SZ_8K + dax_label_reserve, + offset = ALIGN(start + reserve + dax_label_reserve, nd_pfn->align) - start; else return -ENXIO;