Merge branch 'for-4.7/dax' into libnvdimm-for-next

diff --cc drivers/nvdimm/pfn_devs.c
index e071e214febadae71d2d369319b76cd5b6b1a851,58740d7ce81b70c349687793ebe743f9901f1a78..2248056d29e7e562cbb6e1ad898730e75f89fded
--- 1/drivers/nvdimm/pfn_devs.c
--- 2/drivers/nvdimm/pfn_devs.c
+++ b/drivers/nvdimm/pfn_devs.c
@@@ -444,3 -479,186 +479,193 @@@ int nd_pfn_probe(struct device *dev, st
        return rc;
  }
  EXPORT_SYMBOL(nd_pfn_probe);
 -      if (nd_pfn->mode == PFN_MODE_PMEM)
 -              offset = ALIGN(start + SZ_8K + 64 * npfns + dax_label_reserve,
+ 
+ /*
+  * 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_PFN(base);
+ 
+       return PFN_SECTION_ALIGN_DOWN(base_pfn);
+ }
+ 
+ static unsigned long init_altmap_reserve(resource_size_t base)
+ {
+       unsigned long reserve = PHYS_PFN(SZ_8K);
+       unsigned long base_pfn = PHYS_PFN(base);
+ 
+       reserve += base_pfn - PFN_SECTION_ALIGN_DOWN(base_pfn);
+       return reserve;
+ }
+ 
+ static struct vmem_altmap *__nvdimm_setup_pfn(struct nd_pfn *nd_pfn,
+               struct resource *res, struct vmem_altmap *altmap)
+ {
+       struct nd_pfn_sb *pfn_sb = nd_pfn->pfn_sb;
+       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);
+       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;
+       struct vmem_altmap __altmap = {
+               .base_pfn = init_altmap_base(base),
+               .reserve = init_altmap_reserve(base),
+       };
+ 
+       memcpy(res, &nsio->res, sizeof(*res));
+       res->start += start_pad;
+       res->end -= end_trunc;
+ 
+       nd_pfn->mode = le32_to_cpu(nd_pfn->pfn_sb->mode);
+       if (nd_pfn->mode == PFN_MODE_RAM) {
+               if (offset < SZ_8K)
+                       return ERR_PTR(-EINVAL);
+               nd_pfn->npfns = le64_to_cpu(pfn_sb->npfns);
+               altmap = NULL;
+       } else if (nd_pfn->mode == PFN_MODE_PMEM) {
+               nd_pfn->npfns = (resource_size(res) - offset) / PAGE_SIZE;
+               if (le64_to_cpu(nd_pfn->pfn_sb->npfns) > nd_pfn->npfns)
+                       dev_info(&nd_pfn->dev,
+                                       "number of pfns truncated from %lld to %ld\n",
+                                       le64_to_cpu(nd_pfn->pfn_sb->npfns),
+                                       nd_pfn->npfns);
+               memcpy(altmap, &__altmap, sizeof(*altmap));
+               altmap->free = PHYS_PFN(offset - SZ_8K);
+               altmap->alloc = 0;
+       } else
+               return ERR_PTR(-ENXIO);
+ 
+       return altmap;
+ }
+ 
+ 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;
+       u32 start_pad = 0, end_trunc = 0;
+       resource_size_t start, size;
+       struct nd_namespace_io *nsio;
+       struct nd_region *nd_region;
+       struct nd_pfn_sb *pfn_sb;
+       unsigned long npfns;
+       phys_addr_t offset;
+       u64 checksum;
+       int rc;
+ 
+       pfn_sb = devm_kzalloc(&nd_pfn->dev, sizeof(*pfn_sb), GFP_KERNEL);
+       if (!pfn_sb)
+               return -ENOMEM;
+ 
+       nd_pfn->pfn_sb = pfn_sb;
+       rc = nd_pfn_validate(nd_pfn);
+       if (rc != -ENODEV)
+               return rc;
+ 
+       /* no info block, do init */;
+       nd_region = to_nd_region(nd_pfn->dev.parent);
+       if (nd_region->ro) {
+               dev_info(&nd_pfn->dev,
+                               "%s is read-only, unable to init metadata\n",
+                               dev_name(&nd_region->dev));
+               return -ENXIO;
+       }
+ 
+       memset(pfn_sb, 0, sizeof(*pfn_sb));
+ 
+       /*
+        * Check if pmem collides with 'System RAM' when section aligned and
+        * trim it accordingly
+        */
+       nsio = to_nd_namespace_io(&ndns->dev);
+       start = PHYS_SECTION_ALIGN_DOWN(nsio->res.start);
+       size = resource_size(&nsio->res);
+       if (region_intersects(start, size, IORESOURCE_SYSTEM_RAM,
+                               IORES_DESC_NONE) == REGION_MIXED) {
+               start = nsio->res.start;
+               start_pad = PHYS_SECTION_ALIGN_UP(start) - start;
+       }
+ 
+       start = nsio->res.start;
+       size = PHYS_SECTION_ALIGN_UP(start + size) - start;
+       if (region_intersects(start, size, IORESOURCE_SYSTEM_RAM,
+                               IORES_DESC_NONE) == REGION_MIXED) {
+               size = resource_size(&nsio->res);
+               end_trunc = start + size - PHYS_SECTION_ALIGN_DOWN(start + size);
+       }
+ 
+       if (start_pad + end_trunc)
+               dev_info(&nd_pfn->dev, "%s section collision, truncate %d bytes\n",
+                               dev_name(&ndns->dev), start_pad + end_trunc);
+ 
+       /*
+        * Note, we use 64 here for the standard size of struct page,
+        * debugging options may cause it to be larger in which case the
+        * implementation will limit the pfns advertised through
+        * ->direct_access() to those that are included in the memmap.
+        */
+       start += start_pad;
+       size = resource_size(&nsio->res);
+       npfns = (size - start_pad - end_trunc - SZ_8K) / SZ_4K;
 -      else if (nd_pfn->mode == PFN_MODE_RAM)
++      if (nd_pfn->mode == PFN_MODE_PMEM) {
++              unsigned long memmap_size;
++
++              /*
++               * vmemmap_populate_hugepages() allocates the memmap array in
++               * HPAGE_SIZE chunks.
++               */
++              memmap_size = ALIGN(64 * npfns, HPAGE_SIZE);
++              offset = ALIGN(start + SZ_8K + memmap_size + dax_label_reserve,
+                               nd_pfn->align) - start;
++      } else if (nd_pfn->mode == PFN_MODE_RAM)
+               offset = ALIGN(start + SZ_8K + dax_label_reserve,
+                               nd_pfn->align) - start;
+       else
+               return -ENXIO;
+ 
+       if (offset + start_pad + end_trunc >= size) {
+               dev_err(&nd_pfn->dev, "%s unable to satisfy requested alignment\n",
+                               dev_name(&ndns->dev));
+               return -ENXIO;
+       }
+ 
+       npfns = (size - offset - start_pad - end_trunc) / SZ_4K;
+       pfn_sb->mode = cpu_to_le32(nd_pfn->mode);
+       pfn_sb->dataoff = cpu_to_le64(offset);
+       pfn_sb->npfns = cpu_to_le64(npfns);
+       memcpy(pfn_sb->signature, PFN_SIG, PFN_SIG_LEN);
+       memcpy(pfn_sb->uuid, nd_pfn->uuid, 16);
+       memcpy(pfn_sb->parent_uuid, nd_dev_to_uuid(&ndns->dev), 16);
+       pfn_sb->version_major = cpu_to_le16(1);
+       pfn_sb->version_minor = cpu_to_le16(2);
+       pfn_sb->start_pad = cpu_to_le32(start_pad);
+       pfn_sb->end_trunc = cpu_to_le32(end_trunc);
+       pfn_sb->align = cpu_to_le32(nd_pfn->align);
+       checksum = nd_sb_checksum((struct nd_gen_sb *) pfn_sb);
+       pfn_sb->checksum = cpu_to_le64(checksum);
+ 
+       return nvdimm_write_bytes(ndns, SZ_4K, pfn_sb, sizeof(*pfn_sb));
+ }
+ 
+ /*
+  * Determine the effective resource range and vmem_altmap from an nd_pfn
+  * instance.
+  */
+ struct vmem_altmap *nvdimm_setup_pfn(struct nd_pfn *nd_pfn,
+               struct resource *res, struct vmem_altmap *altmap)
+ {
+       int rc;
+ 
+       if (!nd_pfn->uuid || !nd_pfn->ndns)
+               return ERR_PTR(-ENODEV);
+ 
+       rc = nd_pfn_init(nd_pfn);
+       if (rc)
+               return ERR_PTR(rc);
+ 
+       /* we need a valid pfn_sb before we can init a vmem_altmap */
+       return __nvdimm_setup_pfn(nd_pfn, res, altmap);
+ }
+ EXPORT_SYMBOL_GPL(nvdimm_setup_pfn);