device-dax: make pgmap optional for instance creation

The passed in dev_pagemap is only required in the pmem case as the
libnvdimm core may have reserved a vmem_altmap for dev_memremap_pages() to
place the memmap in pmem directly.  In the hmem case there is no agent
reserving an altmap so it can all be handled by a core internal default.

Pass the resource range via a new @range property of 'struct
dev_dax_data'.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Brice Goglin <Brice.Goglin@inria.fr>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Jia He <justin.he@arm.com>
Cc: Joao Martins <joao.m.martins@oracle.com>
Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: David Airlie <airlied@linux.ie>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Hulk Robot <hulkci@huawei.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jason Gunthorpe <jgg@mellanox.com>
Cc: Jason Yan <yanaijie@huawei.com>
Cc: Jeff Moyer <jmoyer@redhat.com>
Cc: "Jérôme Glisse" <jglisse@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: kernel test robot <lkp@intel.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Paul Mackerras <paulus@ozlabs.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Wei Yang <richard.weiyang@linux.alibaba.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lkml.kernel.org/r/159643099958.4062302.10379230791041872886.stgit@dwillia2-desk3.amr.corp.intel.com
Link: https://lkml.kernel.org/r/160106110513.30709.4303239334850606031.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/drivers/dax/bus.c b/drivers/dax/bus.c
index dffa465..96bd64b 100644 (file)
--- a/drivers/dax/bus.c
+++ b/drivers/dax/bus.c
@@ -271,7 +271,7 @@ static ssize_t size_show(struct device *dev,
                struct device_attribute *attr, char *buf)
 {
        struct dev_dax *dev_dax = to_dev_dax(dev);
-       unsigned long long size = resource_size(&dev_dax->region->res);
+       unsigned long long size = range_len(&dev_dax->range);
 
        return sprintf(buf, "%llu\n", size);
 }
@@ -293,19 +293,12 @@ static ssize_t target_node_show(struct device *dev,
 }
 static DEVICE_ATTR_RO(target_node);
 
-static unsigned long long dev_dax_resource(struct dev_dax *dev_dax)
-{
-       struct dax_region *dax_region = dev_dax->region;
-
-       return dax_region->res.start;
-}
-
 static ssize_t resource_show(struct device *dev,
                struct device_attribute *attr, char *buf)
 {
        struct dev_dax *dev_dax = to_dev_dax(dev);
 
-       return sprintf(buf, "%#llx\n", dev_dax_resource(dev_dax));
+       return sprintf(buf, "%#llx\n", dev_dax->range.start);
 }
 static DEVICE_ATTR(resource, 0400, resource_show, NULL);
 
@@ -376,6 +369,7 @@ static void dev_dax_release(struct device *dev)
 
        dax_region_put(dax_region);
        put_dax(dax_dev);
+       kfree(dev_dax->pgmap);
        kfree(dev_dax);
 }
 
@@ -412,7 +406,12 @@ struct dev_dax *devm_create_dev_dax(struct dev_dax_data *data)
        if (!dev_dax)
                return ERR_PTR(-ENOMEM);
 
-       memcpy(&dev_dax->pgmap, data->pgmap, sizeof(struct dev_pagemap));
+       if (data->pgmap) {
+               dev_dax->pgmap = kmemdup(data->pgmap,
+                               sizeof(struct dev_pagemap), GFP_KERNEL);
+               if (!dev_dax->pgmap)
+                       goto err_pgmap;
+       }
 
        /*
         * No 'host' or dax_operations since there is no access to this
@@ -421,18 +420,19 @@ struct dev_dax *devm_create_dev_dax(struct dev_dax_data *data)
        dax_dev = alloc_dax(dev_dax, NULL, NULL, DAXDEV_F_SYNC);
        if (IS_ERR(dax_dev)) {
                rc = PTR_ERR(dax_dev);
-               goto err;
+               goto err_alloc_dax;
        }
 
        /* a device_dax instance is dead while the driver is not attached */
        kill_dax(dax_dev);
 
-       /* from here on we're committed to teardown via dax_dev_release() */
+       /* from here on we're committed to teardown via dev_dax_release() */
        dev = &dev_dax->dev;
        device_initialize(dev);
 
        dev_dax->dax_dev = dax_dev;
        dev_dax->region = dax_region;
+       dev_dax->range = data->range;
        dev_dax->target_node = dax_region->target_node;
        kref_get(&dax_region->kref);
 
@@ -458,8 +458,9 @@ struct dev_dax *devm_create_dev_dax(struct dev_dax_data *data)
                return ERR_PTR(rc);
 
        return dev_dax;
-
- err:
+err_alloc_dax:
+       kfree(dev_dax->pgmap);
+err_pgmap:
        kfree(dev_dax);
 
        return ERR_PTR(rc);

diff --git a/drivers/dax/bus.h b/drivers/dax/bus.h
index 299c2e7..4aeb36d 100644 (file)
--- a/drivers/dax/bus.h
+++ b/drivers/dax/bus.h
@@ -3,6 +3,7 @@
 #ifndef __DAX_BUS_H__
 #define __DAX_BUS_H__
 #include <linux/device.h>
+#include <linux/range.h>
 
 struct dev_dax;
 struct resource;
@@ -21,6 +22,7 @@ struct dev_dax_data {
        struct dax_region *dax_region;
        struct dev_pagemap *pgmap;
        enum dev_dax_subsys subsys;
+       struct range range;
        int id;
 };
 

diff --git a/drivers/dax/dax-private.h b/drivers/dax/dax-private.h
index 8a4c40c..6779f68 100644 (file)
--- a/drivers/dax/dax-private.h
+++ b/drivers/dax/dax-private.h
@@ -41,6 +41,7 @@ struct dax_region {
  * @target_node: effective numa node if dev_dax memory range is onlined
  * @dev - device core
  * @pgmap - pgmap for memmap setup / lifetime (driver owned)
+ * @range: resource range for the instance
  * @dax_mem_res: physical address range of hotadded DAX memory
  * @dax_mem_name: name for hotadded DAX memory via add_memory_driver_managed()
  */
@@ -49,10 +50,16 @@ struct dev_dax {
        struct dax_device *dax_dev;
        int target_node;
        struct device dev;
-       struct dev_pagemap pgmap;
+       struct dev_pagemap *pgmap;
+       struct range range;
        struct resource *dax_kmem_res;
 };
 
+static inline u64 range_len(struct range *range)
+{
+       return range->end - range->start + 1;
+}
+
 static inline struct dev_dax *to_dev_dax(struct device *dev)
 {
        return container_of(dev, struct dev_dax, dev);

diff --git a/drivers/dax/device.c b/drivers/dax/device.c
index c528b72..287cf0a 100644 (file)
--- a/drivers/dax/device.c
+++ b/drivers/dax/device.c
@@ -55,12 +55,12 @@ static int check_vma(struct dev_dax *dev_dax, struct vm_area_struct *vma,
 __weak phys_addr_t dax_pgoff_to_phys(struct dev_dax *dev_dax, pgoff_t pgoff,
                unsigned long size)
 {
-       struct resource *res = &dev_dax->region->res;
+       struct range *range = &dev_dax->range;
        phys_addr_t phys;
 
-       phys = pgoff * PAGE_SIZE + res->start;
-       if (phys >= res->start && phys <= res->end) {
-               if (phys + size - 1 <= res->end)
+       phys = pgoff * PAGE_SIZE + range->start;
+       if (phys >= range->start && phys <= range->end) {
+               if (phys + size - 1 <= range->end)
                        return phys;
        }
 
@@ -396,21 +396,31 @@ int dev_dax_probe(struct device *dev)
 {
        struct dev_dax *dev_dax = to_dev_dax(dev);
        struct dax_device *dax_dev = dev_dax->dax_dev;
-       struct resource *res = &dev_dax->region->res;
+       struct range *range = &dev_dax->range;
+       struct dev_pagemap *pgmap;
        struct inode *inode;
        struct cdev *cdev;
        void *addr;
        int rc;
 
        /* 1:1 map region resource range to device-dax instance range */
-       if (!devm_request_mem_region(dev, res->start, resource_size(res),
+       if (!devm_request_mem_region(dev, range->start, range_len(range),
                                dev_name(dev))) {
-               dev_warn(dev, "could not reserve region %pR\n", res);
+               dev_warn(dev, "could not reserve range: %#llx - %#llx\n",
+                               range->start, range->end);
                return -EBUSY;
        }
 
-       dev_dax->pgmap.type = MEMORY_DEVICE_GENERIC;
-       addr = devm_memremap_pages(dev, &dev_dax->pgmap);
+       pgmap = dev_dax->pgmap;
+       if (!pgmap) {
+               pgmap = devm_kzalloc(dev, sizeof(*pgmap), GFP_KERNEL);
+               if (!pgmap)
+                       return -ENOMEM;
+               pgmap->res.start = range->start;
+               pgmap->res.end = range->end;
+       }
+       pgmap->type = MEMORY_DEVICE_GENERIC;
+       addr = devm_memremap_pages(dev, pgmap);
        if (IS_ERR(addr))
                return PTR_ERR(addr);
 

diff --git a/drivers/dax/hmem/hmem.c b/drivers/dax/hmem/hmem.c
index b84fe17..af82d6b 100644 (file)
--- a/drivers/dax/hmem/hmem.c
+++ b/drivers/dax/hmem/hmem.c
@@ -8,7 +8,6 @@
 static int dax_hmem_probe(struct platform_device *pdev)
 {
        struct device *dev = &pdev->dev;
-       struct dev_pagemap pgmap = { };
        struct dax_region *dax_region;
        struct memregion_info *mri;
        struct dev_dax_data data;
@@ -20,8 +19,6 @@ static int dax_hmem_probe(struct platform_device *pdev)
                return -ENOMEM;
 
        mri = dev->platform_data;
-       memcpy(&pgmap.res, res, sizeof(*res));
-
        dax_region = alloc_dax_region(dev, pdev->id, res, mri->target_node,
                        PMD_SIZE);
        if (!dax_region)
@@ -30,7 +27,10 @@ static int dax_hmem_probe(struct platform_device *pdev)
        data = (struct dev_dax_data) {
                .dax_region = dax_region,
                .id = 0,
-               .pgmap = &pgmap,
+               .range = {
+                       .start = res->start,
+                       .end = res->end,
+               },
        };
        dev_dax = devm_create_dev_dax(&data);
        if (IS_ERR(dev_dax))

diff --git a/drivers/dax/kmem.c b/drivers/dax/kmem.c
index 275aa5f..5bb133d 100644 (file)
--- a/drivers/dax/kmem.c
+++ b/drivers/dax/kmem.c
@@ -22,7 +22,7 @@ static bool any_hotremove_failed;
 int dev_dax_kmem_probe(struct device *dev)
 {
        struct dev_dax *dev_dax = to_dev_dax(dev);
-       struct resource *res = &dev_dax->region->res;
+       struct range *range = &dev_dax->range;
        resource_size_t kmem_start;
        resource_size_t kmem_size;
        resource_size_t kmem_end;
@@ -39,17 +39,17 @@ int dev_dax_kmem_probe(struct device *dev)
         */
        numa_node = dev_dax->target_node;
        if (numa_node < 0) {
-               dev_warn(dev, "rejecting DAX region %pR with invalid node: %d\n",
-                        res, numa_node);
+               dev_warn(dev, "rejecting DAX region with invalid node: %d\n",
+                               numa_node);
                return -EINVAL;
        }
 
        /* Hotplug starting at the beginning of the next block: */
-       kmem_start = ALIGN(res->start, memory_block_size_bytes());
+       kmem_start = ALIGN(range->start, memory_block_size_bytes());
 
-       kmem_size = resource_size(res);
+       kmem_size = range_len(range);
        /* Adjust the size down to compensate for moving up kmem_start: */
-       kmem_size -= kmem_start - res->start;
+       kmem_size -= kmem_start - range->start;
        /* Align the size down to cover only complete blocks: */
        kmem_size &= ~(memory_block_size_bytes() - 1);
        kmem_end = kmem_start + kmem_size;

diff --git a/drivers/dax/pmem/core.c b/drivers/dax/pmem/core.c
index 08ee594..4fa81d3 100644 (file)
--- a/drivers/dax/pmem/core.c
+++ b/drivers/dax/pmem/core.c
@@ -63,6 +63,10 @@ struct dev_dax *__dax_pmem_probe(struct device *dev, enum dev_dax_subsys subsys)
                .id = id,
                .pgmap = &pgmap,
                .subsys = subsys,
+               .range = {
+                       .start = res.start,
+                       .end = res.end,
+               },
        };
        dev_dax = devm_create_dev_dax(&data);
 

diff --git a/tools/testing/nvdimm/dax-dev.c b/tools/testing/nvdimm/dax-dev.c
index 7e5d979..38d8e55 100644 (file)
--- a/tools/testing/nvdimm/dax-dev.c
+++ b/tools/testing/nvdimm/dax-dev.c
@@ -9,12 +9,12 @@
 phys_addr_t dax_pgoff_to_phys(struct dev_dax *dev_dax, pgoff_t pgoff,
                unsigned long size)
 {
-       struct resource *res = &dev_dax->region->res;
+       struct range *range = &dev_dax->range;
        phys_addr_t addr;
 
-       addr = pgoff * PAGE_SIZE + res->start;
-       if (addr >= res->start && addr <= res->end) {
-               if (addr + size - 1 <= res->end) {
+       addr = pgoff * PAGE_SIZE + range->start;
+       if (addr >= range->start && addr <= range->end) {
+               if (addr + size - 1 <= range->end) {
                        if (get_nfit_res(addr)) {
                                struct page *page;