efi/fake_mem: arrange for a resource entry per efi_fake_mem instance

In preparation for attaching a platform device per iomem resource teach
the efi_fake_mem code to create an e820 entry per instance.  Similar to
E820_TYPE_PRAM, bypass merging resource when the e820 map is sanitized.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Brice Goglin <Brice.Goglin@inria.fr>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: David Airlie <airlied@linux.ie>
Cc: David Hildenbrand <david@redhat.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Jason Gunthorpe <jgg@mellanox.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: Michael Ellerman <mpe@ellerman.id.au>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Paul Mackerras <paulus@ozlabs.org>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Wei Yang <richard.weiyang@linux.alibaba.com>
Cc: Will Deacon <will@kernel.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Hulk Robot <hulkci@huawei.com>
Cc: Jason Yan <yanaijie@huawei.com>
Cc: "Jérôme Glisse" <jglisse@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: kernel test robot <lkp@intel.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Vivek Goyal <vgoyal@redhat.com>
Link: https://lkml.kernel.org/r/159643096068.4062302.11590041070221681669.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c
index 983cd53..22aad41 100644 (file)
--- a/arch/x86/kernel/e820.c
+++ b/arch/x86/kernel/e820.c
@@ -305,6 +305,20 @@ static int __init cpcompare(const void *a, const void *b)
        return (ap->addr != ap->entry->addr) - (bp->addr != bp->entry->addr);
 }
 
+static bool e820_nomerge(enum e820_type type)
+{
+       /*
+        * These types may indicate distinct platform ranges aligned to
+        * numa node, protection domain, performance domain, or other
+        * boundaries. Do not merge them.
+        */
+       if (type == E820_TYPE_PRAM)
+               return true;
+       if (type == E820_TYPE_SOFT_RESERVED)
+               return true;
+       return false;
+}
+
 int __init e820__update_table(struct e820_table *table)
 {
        struct e820_entry *entries = table->entries;
@@ -380,7 +394,7 @@ int __init e820__update_table(struct e820_table *table)
                }
 
                /* Continue building up new map based on this information: */
-               if (current_type != last_type || current_type == E820_TYPE_PRAM) {
+               if (current_type != last_type || e820_nomerge(current_type)) {
                        if (last_type != 0)      {
                                new_entries[new_nr_entries].size = change_point[chg_idx]->addr - last_addr;
                                /* Move forward only if the new size was non-zero: */

diff --git a/drivers/firmware/efi/x86_fake_mem.c b/drivers/firmware/efi/x86_fake_mem.c
index e5d6d5a..0bafcc1 100644 (file)
--- a/drivers/firmware/efi/x86_fake_mem.c
+++ b/drivers/firmware/efi/x86_fake_mem.c
@@ -38,7 +38,7 @@ void __init efi_fake_memmap_early(void)
                m_start = mem->range.start;
                m_end = mem->range.end;
                for_each_efi_memory_desc(md) {
-                       u64 start, end;
+                       u64 start, end, size;
 
                        if (md->type != EFI_CONVENTIONAL_MEMORY)
                                continue;
@@ -58,11 +58,17 @@ void __init efi_fake_memmap_early(void)
                         */
                        start = max(start, m_start);
                        end = min(end, m_end);
+                       size = end - start + 1;
 
                        if (end <= start)
                                continue;
-                       e820__range_update(start, end - start + 1, E820_TYPE_RAM,
-                                       E820_TYPE_SOFT_RESERVED);
+
+                       /*
+                        * Ensure each efi_fake_mem instance results in
+                        * a unique e820 resource
+                        */
+                       e820__range_remove(start, size, E820_TYPE_RAM, 1);
+                       e820__range_add(start, size, E820_TYPE_SOFT_RESERVED);
                        e820__update_table(e820_table);
                }
        }