[PATCH v4 3/3] acpi, apei, ghes: Factor out ioremap virtual memory for IRQ and NMI context.

Tomasz Nowicki
2014-06-24T11:41:35Z

GHES currently maps two pages with atomic_ioremap. From now
on, NMI is architectural depended so there is no need to allocate
an NMI page for platforms without NMI support.

To make it possible to not use a second page, swap the existing
page order so that the IRQ context page is first, and the optional
NMI context page is second. Then, use HAVE_ACPI_APEI_NMI to decide
how many pages are to be allocated.

Signed-off-by: Tomasz Nowicki <tomasz.nowicki@linaro.org>
---
arch/x86/kernel/acpi/apei.c | 6 ++++++
drivers/acpi/apei/ghes.c | 18 +++++++++++-------
include/acpi/apei.h | 1 +
3 files changed, 18 insertions(+), 7 deletions(-)

diff --git a/arch/x86/kernel/acpi/apei.c b/arch/x86/kernel/acpi/apei.c
index 12b13de..c280df6 100644
--- a/arch/x86/kernel/acpi/apei.c
+++ b/arch/x86/kernel/acpi/apei.c
@@ -15,6 +15,7 @@
#include <acpi/apei.h>

#include <asm/mce.h>
+#include <asm/tlbflush.h>

int arch_apei_enable_cmcff(struct acpi_hest_header *hest_hdr, void *data)
{
@@ -54,3 +55,8 @@ void arch_apei_report_mem_error(int sev, struct cper_sec_mem_err *mem_err)
apei_mce_report_mem_error(sev, mem_err);
#endif
}
+
+void arch_apei_flush_tlb_one(unsigned long addr)
+{
+ __flush_tlb_one(addr);
+}
diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c
index d1fadf2..6d36f19 100644
--- a/drivers/acpi/apei/ghes.c
+++ b/drivers/acpi/apei/ghes.c
@@ -105,12 +105,16 @@ static DEFINE_MUTEX(ghes_list_mutex);
*/

/*
- * Two virtual pages are used, one for NMI context, the other for
- * IRQ/PROCESS context
+ * Two virtual pages are used, one for IRQ/PROCESS context, the other for
+ * NMI context (optionally).
*/
-#define GHES_IOREMAP_PAGES 2
-#define GHES_IOREMAP_NMI_PAGE(base) (base)
-#define GHES_IOREMAP_IRQ_PAGE(base) ((base) + PAGE_SIZE)
+#ifdef CONFIG_HAVE_ACPI_APEI_NMI
+#define GHES_IOREMAP_PAGES 2
+#else
+#define GHES_IOREMAP_PAGES 1
+#endif
+#define GHES_IOREMAP_IRQ_PAGE(base) (base)
+#define GHES_IOREMAP_NMI_PAGE(base) ((base) + PAGE_SIZE)

/* virtual memory area for atomic ioremap */
static struct vm_struct *ghes_ioremap_area;
@@ -173,7 +177,7 @@ static void ghes_iounmap_nmi(void __iomem *vaddr_ptr)

BUG_ON(vaddr != (unsigned long)GHES_IOREMAP_NMI_PAGE(base));
unmap_kernel_range_noflush(vaddr, PAGE_SIZE);
- __flush_tlb_one(vaddr);
+ arch_apei_flush_tlb_one(vaddr);
}

static void ghes_iounmap_irq(void __iomem *vaddr_ptr)
@@ -183,7 +187,7 @@ static void ghes_iounmap_irq(void __iomem *vaddr_ptr)

BUG_ON(vaddr != (unsigned long)GHES_IOREMAP_IRQ_PAGE(base));
unmap_kernel_range_noflush(vaddr, PAGE_SIZE);
- __flush_tlb_one(vaddr);
+ arch_apei_flush_tlb_one(vaddr);
}

static int ghes_estatus_pool_init(void)
diff --git a/include/acpi/apei.h b/include/acpi/apei.h
index 8a23c95..76284bb 100644
--- a/include/acpi/apei.h
+++ b/include/acpi/apei.h
@@ -44,6 +44,7 @@ int erst_clear(u64 record_id);

int arch_apei_enable_cmcff(struct acpi_hest_header *hest_hdr, void *data);
void arch_apei_report_mem_error(int sev, struct cper_sec_mem_err *mem_err);
+void arch_apei_flush_tlb_one(unsigned long addr);

#endif
#endif
--
1.7.9.5