device-dax/kmem: replace release_resource() with release_mem_region()

Towards removing the mode specific @dax_kmem_res attribute from the
generic 'struct dev_dax', and preparing for multi-range support, change
the kmem driver to use the idiomatic release_mem_region() to pair with the
initial request_mem_region().  This also eliminates the need to open code
the release of the resource allocated by request_mem_region().

As there are no more dax_kmem_res users, delete this struct member.

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/160106112239.30709.15909567572288425294.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/drivers/dax/dax-private.h b/drivers/dax/dax-private.h
index 6779f68..12a2dbc 100644 (file)
--- a/drivers/dax/dax-private.h
+++ b/drivers/dax/dax-private.h
@@ -42,8 +42,6 @@ struct dax_region {
  * @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()
  */
 struct dev_dax {
        struct dax_region *region;
@@ -52,7 +50,6 @@ struct dev_dax {
        struct device dev;
        struct dev_pagemap *pgmap;
        struct range range;
-       struct resource *dax_kmem_res;
 };
 
 static inline u64 range_len(struct range *range)

diff --git a/drivers/dax/kmem.c b/drivers/dax/kmem.c
index 6fe2cb1..e56fc68 100644 (file)
--- a/drivers/dax/kmem.c
+++ b/drivers/dax/kmem.c
@@ -33,7 +33,7 @@ int dev_dax_kmem_probe(struct device *dev)
 {
        struct dev_dax *dev_dax = to_dev_dax(dev);
        struct range range = dax_kmem_range(dev_dax);
-       struct resource *new_res;
+       struct resource *res;
        char *res_name;
        int numa_node;
        int rc;
@@ -56,8 +56,8 @@ int dev_dax_kmem_probe(struct device *dev)
                return -ENOMEM;
 
        /* Region is permanently reserved if hotremove fails. */
-       new_res = request_mem_region(range.start, range_len(&range), res_name);
-       if (!new_res) {
+       res = request_mem_region(range.start, range_len(&range), res_name);
+       if (!res) {
                dev_warn(dev, "could not reserve region [%#llx-%#llx]\n", range.start, range.end);
                kfree(res_name);
                return -EBUSY;
@@ -69,23 +69,20 @@ int dev_dax_kmem_probe(struct device *dev)
         * inherit flags from the parent since it may set new flags
         * unknown to us that will break add_memory() below.
         */
-       new_res->flags = IORESOURCE_SYSTEM_RAM;
+       res->flags = IORESOURCE_SYSTEM_RAM;
 
        /*
         * Ensure that future kexec'd kernels will not treat this as RAM
         * automatically.
         */
-       rc = add_memory_driver_managed(numa_node, new_res->start,
-                                      resource_size(new_res), kmem_name);
+       rc = add_memory_driver_managed(numa_node, range.start, range_len(&range), kmem_name);
        if (rc) {
-               release_resource(new_res);
-               kfree(new_res);
+               release_mem_region(range.start, range_len(&range));
                kfree(res_name);
                return rc;
        }
 
        dev_set_drvdata(dev, res_name);
-       dev_dax->dax_kmem_res = new_res;
 
        return 0;
 }
@@ -95,7 +92,6 @@ static int dev_dax_kmem_remove(struct device *dev)
 {
        struct dev_dax *dev_dax = to_dev_dax(dev);
        struct range range = dax_kmem_range(dev_dax);
-       struct resource *res = dev_dax->dax_kmem_res;
        const char *res_name = dev_get_drvdata(dev);
        int rc;
 
@@ -114,10 +110,8 @@ static int dev_dax_kmem_remove(struct device *dev)
        }
 
        /* Release and free dax resources */
-       release_resource(res);
-       kfree(res);
+       release_mem_region(range.start, range_len(&range));
        kfree(res_name);
-       dev_dax->dax_kmem_res = NULL;
 
        return 0;
 }