]> git.kernelconcepts.de Git - karo-tx-linux.git/commitdiff
libnvdimm, pmem: 'struct page' for pmem
authorDan Williams <dan.j.williams@intel.com>
Sat, 1 Aug 2015 06:16:37 +0000 (02:16 -0400)
committerDan Williams <dan.j.williams@intel.com>
Sat, 29 Aug 2015 03:40:04 +0000 (23:40 -0400)
Enable the pmem driver to handle PFN device instances.  Attaching a pmem
namespace to a pfn device triggers the driver to allocate and initialize
struct page entries for pmem.  Memory capacity for this allocation comes
exclusively from RAM for now which is suitable for low PMEM to RAM
ratios.  This mechanism will be expanded later for setting an "allocate
from PMEM" policy.

Cc: Boaz Harrosh <boaz@plexistor.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
drivers/nvdimm/Kconfig
drivers/nvdimm/nd.h
drivers/nvdimm/pfn_devs.c
drivers/nvdimm/pmem.c
tools/testing/nvdimm/Kbuild
tools/testing/nvdimm/test/iomap.c

index ace25b53b7556530a4191e0eae803ce76635317e..53c11621d5b16fd6eb33764469b4f1d4659fe8a5 100644 (file)
@@ -76,6 +76,7 @@ config ND_PFN
 config NVDIMM_PFN
        bool "PFN: Map persistent (device) memory"
        default LIBNVDIMM
+       depends on ZONE_DEVICE
        select ND_CLAIM
        help
          Map persistent memory, i.e. advertise it to the memory
index 8da2be1cecb8ca33154b069fe76c0c6a5effdc66..83e5d09350123bceab6c02d63c122567df7d8ca4 100644 (file)
@@ -217,6 +217,7 @@ struct nd_pfn *to_nd_pfn(struct device *dev);
 int nd_pfn_probe(struct nd_namespace_common *ndns, void *drvdata);
 bool is_nd_pfn(struct device *dev);
 struct device *nd_pfn_create(struct nd_region *nd_region);
+int nd_pfn_validate(struct nd_pfn *nd_pfn);
 #else
 static inline int nd_pfn_probe(struct nd_namespace_common *ndns, void *drvdata)
 {
@@ -232,6 +233,11 @@ static inline struct device *nd_pfn_create(struct nd_region *nd_region)
 {
        return NULL;
 }
+
+static inline int nd_pfn_validate(struct nd_pfn *nd_pfn)
+{
+       return -ENODEV;
+}
 #endif
 
 struct nd_region *to_nd_region(struct device *dev);
index f708d63709a5d3fb82b03d13612c196a01ca59d7..3fd7d0d81a470b4cff54b093b0c24c6d14c376b5 100644 (file)
@@ -228,7 +228,7 @@ struct device *nd_pfn_create(struct nd_region *nd_region)
        return dev;
 }
 
-static int nd_pfn_validate(struct nd_pfn *nd_pfn)
+int nd_pfn_validate(struct nd_pfn *nd_pfn)
 {
        struct nd_namespace_common *ndns = nd_pfn->ndns;
        struct nd_pfn_sb *pfn_sb = nd_pfn->pfn_sb;
@@ -286,10 +286,10 @@ static int nd_pfn_validate(struct nd_pfn *nd_pfn)
         */
        offset = le64_to_cpu(pfn_sb->dataoff);
        nsio = to_nd_namespace_io(&ndns->dev);
-       if ((nsio->res.start + offset) & (ND_PFN_ALIGN - 1)) {
+       if (nsio->res.start & ND_PFN_MASK) {
                dev_err(&nd_pfn->dev,
-                               "init failed: %s with offset %#llx not section aligned\n",
-                               dev_name(&ndns->dev), offset);
+                               "init failed: %s not section aligned\n",
+                               dev_name(&ndns->dev));
                return -EBUSY;
        } else if (offset >= resource_size(&nsio->res)) {
                dev_err(&nd_pfn->dev, "pfn array size exceeds capacity of %s\n",
@@ -299,6 +299,7 @@ static int nd_pfn_validate(struct nd_pfn *nd_pfn)
 
        return 0;
 }
+EXPORT_SYMBOL(nd_pfn_validate);
 
 int nd_pfn_probe(struct nd_namespace_common *ndns, void *drvdata)
 {
index 20bf122328da50ec31380ce7f03ed381409a59af..2f885e5d9c365182044e57e84894992629e8e6bc 100644 (file)
 #include <linux/init.h>
 #include <linux/platform_device.h>
 #include <linux/module.h>
+#include <linux/memory_hotplug.h>
 #include <linux/moduleparam.h>
+#include <linux/vmalloc.h>
 #include <linux/slab.h>
 #include <linux/pmem.h>
 #include <linux/nd.h>
+#include "pfn.h"
 #include "nd.h"
 
 struct pmem_device {
        struct request_queue    *pmem_queue;
        struct gendisk          *pmem_disk;
+       struct nd_namespace_common *ndns;
 
        /* One contiguous memory region per device */
        phys_addr_t             phys_addr;
+       /* when non-zero this device is hosting a 'pfn' instance */
+       phys_addr_t             data_offset;
        void __pmem             *virt_addr;
        size_t                  size;
 };
@@ -44,7 +50,7 @@ static void pmem_do_bvec(struct pmem_device *pmem, struct page *page,
                        sector_t sector)
 {
        void *mem = kmap_atomic(page);
-       size_t pmem_off = sector << 9;
+       phys_addr_t pmem_off = sector * 512 + pmem->data_offset;
        void __pmem *pmem_addr = pmem->virt_addr + pmem_off;
 
        if (rw == READ) {
@@ -95,16 +101,23 @@ static long pmem_direct_access(struct block_device *bdev, sector_t sector,
                      void __pmem **kaddr, unsigned long *pfn)
 {
        struct pmem_device *pmem = bdev->bd_disk->private_data;
-       size_t offset = sector << 9;
-
-       if (!pmem)
-               return -ENODEV;
+       resource_size_t offset = sector * 512 + pmem->data_offset;
+       resource_size_t size;
+
+       if (pmem->data_offset) {
+               /*
+                * Limit the direct_access() size to what is covered by
+                * the memmap
+                */
+               size = (pmem->size - offset) & ~ND_PFN_MASK;
+       } else
+               size = pmem->size - offset;
 
        /* FIXME convert DAX to comprehend that this mapping has a lifetime */
        *kaddr = pmem->virt_addr + offset;
        *pfn = (pmem->phys_addr + offset) >> PAGE_SHIFT;
 
-       return pmem->size - offset;
+       return size;
 }
 
 static const struct block_device_operations pmem_fops = {
@@ -144,13 +157,16 @@ static struct pmem_device *pmem_alloc(struct device *dev,
 
 static void pmem_detach_disk(struct pmem_device *pmem)
 {
+       if (!pmem->pmem_disk)
+               return;
+
        del_gendisk(pmem->pmem_disk);
        put_disk(pmem->pmem_disk);
        blk_cleanup_queue(pmem->pmem_queue);
 }
 
-static int pmem_attach_disk(struct nd_namespace_common *ndns,
-               struct pmem_device *pmem)
+static int pmem_attach_disk(struct device *dev,
+               struct nd_namespace_common *ndns, struct pmem_device *pmem)
 {
        struct gendisk *disk;
 
@@ -177,8 +193,8 @@ static int pmem_attach_disk(struct nd_namespace_common *ndns,
        disk->queue             = pmem->pmem_queue;
        disk->flags             = GENHD_FL_EXT_DEVT;
        nvdimm_namespace_disk_name(ndns, disk->disk_name);
-       disk->driverfs_dev = &ndns->dev;
-       set_capacity(disk, pmem->size >> 9);
+       disk->driverfs_dev = dev;
+       set_capacity(disk, (pmem->size - pmem->data_offset) / 512);
        pmem->pmem_disk = disk;
 
        add_disk(disk);
@@ -207,6 +223,154 @@ static int pmem_rw_bytes(struct nd_namespace_common *ndns,
        return 0;
 }
 
+static int nd_pfn_init(struct nd_pfn *nd_pfn)
+{
+       struct nd_pfn_sb *pfn_sb = kzalloc(sizeof(*pfn_sb), GFP_KERNEL);
+       struct pmem_device *pmem = dev_get_drvdata(&nd_pfn->dev);
+       struct nd_namespace_common *ndns = nd_pfn->ndns;
+       struct nd_region *nd_region;
+       unsigned long npfns;
+       phys_addr_t offset;
+       u64 checksum;
+       int rc;
+
+       if (!pfn_sb)
+               return -ENOMEM;
+
+       nd_pfn->pfn_sb = pfn_sb;
+       rc = nd_pfn_validate(nd_pfn);
+       if (rc == 0 || rc == -EBUSY)
+               return rc;
+
+       /* section alignment for simple hotplug */
+       if (nvdimm_namespace_capacity(ndns) < ND_PFN_ALIGN
+                       || pmem->phys_addr & ND_PFN_MASK)
+               return -ENODEV;
+
+       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));
+               goto err;
+       }
+
+       memset(pfn_sb, 0, sizeof(*pfn_sb));
+       npfns = (pmem->size - SZ_8K) / SZ_4K;
+       /*
+        * 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.
+        */
+       if (nd_pfn->mode == PFN_MODE_PMEM)
+               offset = ALIGN(SZ_8K + 64 * npfns, PMD_SIZE);
+       else if (nd_pfn->mode == PFN_MODE_RAM)
+               offset = SZ_8K;
+       else
+               goto err;
+
+       npfns = (pmem->size - offset) / 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);
+       pfn_sb->version_major = cpu_to_le16(1);
+       checksum = nd_sb_checksum((struct nd_gen_sb *) pfn_sb);
+       pfn_sb->checksum = cpu_to_le64(checksum);
+
+       rc = nvdimm_write_bytes(ndns, SZ_4K, pfn_sb, sizeof(*pfn_sb));
+       if (rc)
+               goto err;
+
+       return 0;
+ err:
+       nd_pfn->pfn_sb = NULL;
+       kfree(pfn_sb);
+       return -ENXIO;
+}
+
+static int nvdimm_namespace_detach_pfn(struct nd_namespace_common *ndns)
+{
+       struct nd_pfn *nd_pfn = to_nd_pfn(ndns->claim);
+       struct pmem_device *pmem;
+
+       /* free pmem disk */
+       pmem = dev_get_drvdata(&nd_pfn->dev);
+       pmem_detach_disk(pmem);
+
+       /* release nd_pfn resources */
+       kfree(nd_pfn->pfn_sb);
+       nd_pfn->pfn_sb = NULL;
+
+       return 0;
+}
+
+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 nd_pfn_sb *pfn_sb;
+       struct pmem_device *pmem;
+       phys_addr_t offset;
+       int rc;
+
+       if (!nd_pfn->uuid || !nd_pfn->ndns)
+               return -ENODEV;
+
+       nd_region = to_nd_region(dev->parent);
+       rc = nd_pfn_init(nd_pfn);
+       if (rc)
+               return rc;
+
+       if (PAGE_SIZE != SZ_4K) {
+               dev_err(dev, "only supported on systems with 4K PAGE_SIZE\n");
+               return -ENXIO;
+       }
+       if (nsio->res.start & ND_PFN_MASK) {
+               dev_err(dev, "%s not memory hotplug section aligned\n",
+                               dev_name(&ndns->dev));
+               return -ENXIO;
+       }
+
+       pfn_sb = nd_pfn->pfn_sb;
+       offset = le64_to_cpu(pfn_sb->dataoff);
+       nd_pfn->mode = le32_to_cpu(nd_pfn->pfn_sb->mode);
+       if (nd_pfn->mode == PFN_MODE_RAM) {
+               if (offset != SZ_8K)
+                       return -EINVAL;
+               nd_pfn->npfns = le64_to_cpu(pfn_sb->npfns);
+               altmap = NULL;
+       } else {
+               rc = -ENXIO;
+               goto err;
+       }
+
+       /* establish pfn range for lookup, and switch to direct map */
+       pmem = dev_get_drvdata(dev);
+       memunmap_pmem(dev, pmem->virt_addr);
+       pmem->virt_addr = (void __pmem *)devm_memremap_pages(dev, &nsio->res);
+       if (IS_ERR(pmem->virt_addr)) {
+               rc = PTR_ERR(pmem->virt_addr);
+               goto err;
+       }
+
+       /* attach pmem disk in "pfn-mode" */
+       pmem->data_offset = offset;
+       rc = pmem_attach_disk(dev, ndns, pmem);
+       if (rc)
+               goto err;
+
+       return rc;
+ err:
+       nvdimm_namespace_detach_pfn(ndns);
+       return rc;
+}
+
 static int nd_pmem_probe(struct device *dev)
 {
        struct nd_region *nd_region = to_nd_region(dev->parent);
@@ -223,16 +387,27 @@ static int nd_pmem_probe(struct device *dev)
        if (IS_ERR(pmem))
                return PTR_ERR(pmem);
 
+       pmem->ndns = ndns;
        dev_set_drvdata(dev, pmem);
        ndns->rw_bytes = pmem_rw_bytes;
 
        if (is_nd_btt(dev))
                return nvdimm_namespace_attach_btt(ndns);
 
-       if (nd_btt_probe(ndns, pmem) == 0)
+       if (is_nd_pfn(dev))
+               return nvdimm_namespace_attach_pfn(ndns);
+
+       if (nd_btt_probe(ndns, pmem) == 0) {
                /* we'll come back as btt-pmem */
                return -ENXIO;
-       return pmem_attach_disk(ndns, pmem);
+       }
+
+       if (nd_pfn_probe(ndns, pmem) == 0) {
+               /* we'll come back as pfn-pmem */
+               return -ENXIO;
+       }
+
+       return pmem_attach_disk(dev, ndns, pmem);
 }
 
 static int nd_pmem_remove(struct device *dev)
@@ -240,7 +415,9 @@ static int nd_pmem_remove(struct device *dev)
        struct pmem_device *pmem = dev_get_drvdata(dev);
 
        if (is_nd_btt(dev))
-               nvdimm_namespace_detach_btt(to_nd_btt(dev)->ndns);
+               nvdimm_namespace_detach_btt(pmem->ndns);
+       else if (is_nd_pfn(dev))
+               nvdimm_namespace_detach_pfn(pmem->ndns);
        else
                pmem_detach_disk(pmem);
 
index 99e70f0729be1d7f46a29b0ef1e413480f7ce4a1..38b00ecb2ed55a6313f54e6cadd08f67a564fe26 100644 (file)
@@ -2,6 +2,7 @@ ldflags-y += --wrap=ioremap_wc
 ldflags-y += --wrap=memremap
 ldflags-y += --wrap=devm_ioremap_nocache
 ldflags-y += --wrap=devm_memremap
+ldflags-y += --wrap=devm_memunmap
 ldflags-y += --wrap=ioremap_nocache
 ldflags-y += --wrap=iounmap
 ldflags-y += --wrap=memunmap
index 179d2289f3a8289874edccfe6ffcbe8cffd058e4..b7251314bbc038d598457b119e26e5cd3c2e3378 100644 (file)
@@ -108,6 +108,19 @@ void *__wrap_memremap(resource_size_t offset, size_t size,
 }
 EXPORT_SYMBOL(__wrap_memremap);
 
+void __wrap_devm_memunmap(struct device *dev, void *addr)
+{
+       struct nfit_test_resource *nfit_res;
+
+       rcu_read_lock();
+       nfit_res = get_nfit_res((unsigned long) addr);
+       rcu_read_unlock();
+       if (nfit_res)
+               return;
+       return devm_memunmap(dev, addr);
+}
+EXPORT_SYMBOL(__wrap_devm_memunmap);
+
 void __iomem *__wrap_ioremap_nocache(resource_size_t offset, unsigned long size)
 {
        return __nfit_test_ioremap(offset, size, ioremap_nocache);