mm/memremap_pages: convert to 'struct range'

The 'struct resource' in 'struct dev_pagemap' is only used for holding
resource span information.  The other fields, 'name', 'flags', 'desc',
'parent', 'sibling', and 'child' are all unused wasted space.

This is in preparation for introducing a multi-range extension of
devm_memremap_pages().

The bulk of this change is unwinding all the places internal to libnvdimm
that used 'struct resource' unnecessarily, and replacing instances of
'struct dev_pagemap'.res with 'struct dev_pagemap'.range.

P2PDMA had a minor usage of the resource flags field, but only to report
failures with "%pR".  That is replaced with an open coded print of the
range.

[dan.carpenter@oracle.com: mm/hmm/test: use after free in dmirror_allocate_chunk()]
  Link: https://lkml.kernel.org/r/20200926121402.GA7467@kadam

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>	[xen]
Cc: Paul Mackerras <paulus@ozlabs.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: "Jérôme Glisse" <jglisse@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brice Goglin <Brice.Goglin@inria.fr>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Hildenbrand <david@redhat.com>
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: Jia He <justin.he@arm.com>
Cc: Joao Martins <joao.m.martins@oracle.com>
Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: kernel test robot <lkp@intel.com>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Wei Yang <richard.weiyang@linux.alibaba.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lkml.kernel.org/r/159643103173.4062302.768998885691711532.stgit@dwillia2-desk3.amr.corp.intel.com
Link: https://lkml.kernel.org/r/160106115761.30709.13539840236873663620.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 7 insertions, 6 deletions

diff --git a/arch/powerpc/kvm/book3s_hv_uvmem.c b/arch/powerpc/kvm/book3s_hv_uvmem.c
index 7705d5557239..29ec555055c2 100644
--- a/arch/powerpc/kvm/book3s_hv_uvmem.c
+++ b/arch/powerpc/kvm/book3s_hv_uvmem.c
@@ -687,9 +687,9 @@ static struct page *kvmppc_uvmem_get_page(unsigned long gpa, struct kvm *kvm)
 	struct kvmppc_uvmem_page_pvt *pvt;
 	unsigned long pfn_last, pfn_first;
 
-	pfn_first = kvmppc_uvmem_pgmap.res.start >> PAGE_SHIFT;
+	pfn_first = kvmppc_uvmem_pgmap.range.start >> PAGE_SHIFT;
 	pfn_last = pfn_first +
-		   (resource_size(&kvmppc_uvmem_pgmap.res) >> PAGE_SHIFT);
+		   (range_len(&kvmppc_uvmem_pgmap.range) >> PAGE_SHIFT);
 
 	spin_lock(&kvmppc_uvmem_bitmap_lock);
 	bit = find_first_zero_bit(kvmppc_uvmem_bitmap,
@@ -1007,7 +1007,7 @@ static vm_fault_t kvmppc_uvmem_migrate_to_ram(struct vm_fault *vmf)
 static void kvmppc_uvmem_page_free(struct page *page)
 {
 	unsigned long pfn = page_to_pfn(page) -
-			(kvmppc_uvmem_pgmap.res.start >> PAGE_SHIFT);
+			(kvmppc_uvmem_pgmap.range.start >> PAGE_SHIFT);
 	struct kvmppc_uvmem_page_pvt *pvt;
 
 	spin_lock(&kvmppc_uvmem_bitmap_lock);
@@ -1170,7 +1170,8 @@ int kvmppc_uvmem_init(void)
 	}
 
 	kvmppc_uvmem_pgmap.type = MEMORY_DEVICE_PRIVATE;
-	kvmppc_uvmem_pgmap.res = *res;
+	kvmppc_uvmem_pgmap.range.start = res->start;
+	kvmppc_uvmem_pgmap.range.end = res->end;
 	kvmppc_uvmem_pgmap.ops = &kvmppc_uvmem_ops;
 	/* just one global instance: */
 	kvmppc_uvmem_pgmap.owner = &kvmppc_uvmem_pgmap;
@@ -1205,7 +1206,7 @@ void kvmppc_uvmem_free(void)
 		return;
 
 	memunmap_pages(&kvmppc_uvmem_pgmap);
-	release_mem_region(kvmppc_uvmem_pgmap.res.start,
-			   resource_size(&kvmppc_uvmem_pgmap.res));
+	release_mem_region(kvmppc_uvmem_pgmap.range.start,
+			   range_len(&kvmppc_uvmem_pgmap.range));
 	kfree(kvmppc_uvmem_bitmap);
 }