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.
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: x86@kernel.org Acked-by: Ard Biesheuvel ardb@kernel.org Signed-off-by: Dan Williams dan.j.williams@intel.com --- arch/x86/kernel/e820.c | 16 +++++++++++++++- drivers/firmware/efi/x86_fake_mem.c | 12 +++++++++--- 2 files changed, 24 insertions(+), 4 deletions(-)
diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c index 983cd53ed4c9..22aad412f965 100644 --- 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 e5d6d5a1b240..0bafcc1bb0f6 100644 --- 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); } }