[PATCH 07/11] ACPI / APEI: Split fixmap pages for arm64 NMI-like notifications

James Morse
2018-02-15T18:56:02Z

Now that ghes uses the fixmap addresses and locks via some indirection
we can support multiple NMI-like notifications on arm64.

These should be named after their notification method. x86's
NOTIFY_NMI already is, change the SEA fixmap entry to be called
FIX_APEI_GHES_SEA.

Future patches can add support for FIX_APEI_GHES_SEI and
FIX_APEI_GHES_SDEI_{NORMAL,CRITICAL}.

Signed-off-by: James Morse <james.morse@arm.com>
CC: Tyler Baicar <tbaicar@codeaurora.org>
---
arch/arm64/include/asm/fixmap.h | 4 +++-
drivers/acpi/apei/ghes.c | 11 ++++++-----
2 files changed, 9 insertions(+), 6 deletions(-)

diff --git a/arch/arm64/include/asm/fixmap.h b/arch/arm64/include/asm/fixmap.h
index ec1e6d6fa14c..c3974517c2cb 100644
--- a/arch/arm64/include/asm/fixmap.h
+++ b/arch/arm64/include/asm/fixmap.h
@@ -55,7 +55,9 @@ enum fixed_addresses {
#ifdef CONFIG_ACPI_APEI_GHES
/* Used for GHES mapping from assorted contexts */
FIX_APEI_GHES_IRQ,
- FIX_APEI_GHES_NMI,
+#ifdef CONFIG_ACPI_APEI_SEA
+ FIX_APEI_GHES_SEA,
+#endif
#endif /* CONFIG_ACPI_APEI_GHES */

#ifdef CONFIG_UNMAP_KERNEL_AT_EL0
diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c
index 70ccb309a9d8..280c0a58c700 100644
--- a/drivers/acpi/apei/ghes.c
+++ b/drivers/acpi/apei/ghes.c
@@ -119,7 +119,6 @@ static DEFINE_MUTEX(ghes_list_mutex);
* handler, but general ioremap can not be used in atomic context, so
* the fixmap is used instead.
*/
-static DEFINE_RAW_SPINLOCK(ghes_fixmap_lock_nmi);
static DEFINE_SPINLOCK(ghes_fixmap_lock_irq);

static struct gen_pool *ghes_estatus_pool;
@@ -954,6 +953,7 @@ static struct notifier_block ghes_notifier_hed = {

#ifdef CONFIG_ACPI_APEI_SEA
static LIST_HEAD(ghes_sea);
+static DEFINE_RAW_SPINLOCK(ghes_fixmap_lock_sea);

/*
* Return 0 only if one of the SEA error sources successfully reported an error
@@ -966,8 +966,8 @@ int ghes_notify_sea(void)

static void ghes_sea_add(struct ghes *ghes)
{
- ghes->nmi_fixmap_lock = &ghes_fixmap_lock_nmi;
- ghes->fixmap_idx = FIX_APEI_GHES_NMI;
+ ghes->nmi_fixmap_lock = &ghes_fixmap_lock_sea;
+ ghes->fixmap_idx = FIX_APEI_GHES_SEA;
ghes_estatus_queue_grow_pool(ghes);

mutex_lock(&ghes_list_mutex);
@@ -991,12 +991,13 @@ static inline void ghes_sea_remove(struct ghes *ghes) { }

#ifdef CONFIG_HAVE_ACPI_APEI_NMI
/*
- * NMI may be triggered on any CPU, so ghes_in_nmi is used for
- * having only one concurrent reader.
+ * NOTIFY_NMI may be triggered on any CPU, so ghes_in_nmi is
+ * used for having only one concurrent reader.
*/
static atomic_t ghes_in_nmi = ATOMIC_INIT(0);

static LIST_HEAD(ghes_nmi);
+static DEFINE_RAW_SPINLOCK(ghes_fixmap_lock_nmi);

static int ghes_notify_nmi(unsigned int cmd, struct pt_regs *regs)
{
--
2.15.1