libnvdimm, pfn, pmem: allocate memmap array in persistent memory

Use the new vmem_altmap capability to enable the pmem driver to arrange
for a struct page memmap to be established in persistent memory.

[linux@roeck-us.net: mn10300: declare __pfn_to_phys() to fix build error]
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/arch/ia64/include/asm/page.h b/arch/ia64/include/asm/page.h
index ec48bb9..e8c486e 100644 (file)
--- a/arch/ia64/include/asm/page.h
+++ b/arch/ia64/include/asm/page.h
@@ -105,6 +105,7 @@ extern struct page *vmem_map;
 #ifdef CONFIG_DISCONTIGMEM
 # define page_to_pfn(page)     ((unsigned long) (page - vmem_map))
 # define pfn_to_page(pfn)      (vmem_map + (pfn))
+# define __pfn_to_phys(pfn)    PFN_PHYS(pfn)
 #else
 # include <asm-generic/memory_model.h>
 #endif

diff --git a/arch/mn10300/include/asm/page.h b/arch/mn10300/include/asm/page.h
index 8288e12..3810a6f 100644 (file)
--- a/arch/mn10300/include/asm/page.h
+++ b/arch/mn10300/include/asm/page.h
@@ -107,6 +107,7 @@ static inline int get_order(unsigned long size)
 #define pfn_to_kaddr(pfn)      __va((pfn) << PAGE_SHIFT)
 #define pfn_to_page(pfn)       (mem_map + ((pfn) - __pfn_disp))
 #define page_to_pfn(page)      ((unsigned long)((page) - mem_map) + __pfn_disp)
+#define __pfn_to_phys(pfn)     PFN_PHYS(pfn)
 
 #define pfn_valid(pfn)                                 \
 ({                                                     \

diff --git a/drivers/nvdimm/pfn_devs.c b/drivers/nvdimm/pfn_devs.c
index f9b674b..0cc9048 100644 (file)
--- a/drivers/nvdimm/pfn_devs.c
+++ b/drivers/nvdimm/pfn_devs.c
@@ -83,8 +83,7 @@ static ssize_t mode_store(struct device *dev,
 
                if (strncmp(buf, "pmem\n", n) == 0
                                || strncmp(buf, "pmem", n) == 0) {
-                       /* TODO: allocate from PMEM support */
-                       rc = -ENOTTY;
+                       nd_pfn->mode = PFN_MODE_PMEM;
                } else if (strncmp(buf, "ram\n", n) == 0
                                || strncmp(buf, "ram", n) == 0)
                        nd_pfn->mode = PFN_MODE_RAM;

diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c
index be3f854..03d8668 100644 (file)
--- a/drivers/nvdimm/pmem.c
+++ b/drivers/nvdimm/pmem.c
@@ -357,12 +357,16 @@ static int nvdimm_namespace_attach_pfn(struct nd_namespace_common *ndns)
        struct nd_namespace_io *nsio = to_nd_namespace_io(&ndns->dev);
        struct nd_pfn *nd_pfn = to_nd_pfn(ndns->claim);
        struct device *dev = &nd_pfn->dev;
-       struct vmem_altmap *altmap;
        struct nd_region *nd_region;
+       struct vmem_altmap *altmap;
        struct nd_pfn_sb *pfn_sb;
        struct pmem_device *pmem;
        phys_addr_t offset;
        int rc;
+       struct vmem_altmap __altmap = {
+               .base_pfn = __phys_to_pfn(nsio->res.start),
+               .reserve = __phys_to_pfn(SZ_8K),
+       };
 
        if (!nd_pfn->uuid || !nd_pfn->ndns)
                return -ENODEV;
@@ -380,6 +384,17 @@ static int nvdimm_namespace_attach_pfn(struct nd_namespace_common *ndns)
                        return -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(&nsio->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);
+               altmap = & __altmap;
+               altmap->free = __phys_to_pfn(offset - SZ_8K);
+               altmap->alloc = 0;
        } else {
                rc = -ENXIO;
                goto err;
@@ -389,7 +404,7 @@ static int nvdimm_namespace_attach_pfn(struct nd_namespace_common *ndns)
        pmem = dev_get_drvdata(dev);
        devm_memunmap(dev, (void __force *) pmem->virt_addr);
        pmem->virt_addr = (void __pmem *) devm_memremap_pages(dev, &nsio->res,
-                       NULL);
+                       altmap);
        pmem->pfn_flags |= PFN_MAP;
        if (IS_ERR(pmem->virt_addr)) {
                rc = PTR_ERR(pmem->virt_addr);