v4.19.13 snapshot.
diff --git a/drivers/firmware/efi/runtime-wrappers.c b/drivers/firmware/efi/runtime-wrappers.c
new file mode 100644
index 0000000..aa66cbf
--- /dev/null
+++ b/drivers/firmware/efi/runtime-wrappers.c
@@ -0,0 +1,486 @@
+/*
+ * runtime-wrappers.c - Runtime Services function call wrappers
+ *
+ * Implementation summary:
+ * -----------------------
+ * 1. When user/kernel thread requests to execute efi_runtime_service(),
+ * enqueue work to efi_rts_wq.
+ * 2. Caller thread waits for completion until the work is finished
+ * because it's dependent on the return status and execution of
+ * efi_runtime_service().
+ * For instance, get_variable() and get_next_variable().
+ *
+ * Copyright (C) 2014 Linaro Ltd. <ard.biesheuvel@linaro.org>
+ *
+ * Split off from arch/x86/platform/efi/efi.c
+ *
+ * Copyright (C) 1999 VA Linux Systems
+ * Copyright (C) 1999 Walt Drummond <drummond@valinux.com>
+ * Copyright (C) 1999-2002 Hewlett-Packard Co.
+ * Copyright (C) 2005-2008 Intel Co.
+ * Copyright (C) 2013 SuSE Labs
+ *
+ * This file is released under the GPLv2.
+ */
+
+#define pr_fmt(fmt) "efi: " fmt
+
+#include <linux/bug.h>
+#include <linux/efi.h>
+#include <linux/irqflags.h>
+#include <linux/mutex.h>
+#include <linux/semaphore.h>
+#include <linux/stringify.h>
+#include <linux/workqueue.h>
+#include <linux/completion.h>
+
+#include <asm/efi.h>
+
+/*
+ * Wrap around the new efi_call_virt_generic() macros so that the
+ * code doesn't get too cluttered:
+ */
+#define efi_call_virt(f, args...) \
+ efi_call_virt_pointer(efi.systab->runtime, f, args)
+#define __efi_call_virt(f, args...) \
+ __efi_call_virt_pointer(efi.systab->runtime, f, args)
+
+/* efi_runtime_service() function identifiers */
+enum efi_rts_ids {
+ GET_TIME,
+ SET_TIME,
+ GET_WAKEUP_TIME,
+ SET_WAKEUP_TIME,
+ GET_VARIABLE,
+ GET_NEXT_VARIABLE,
+ SET_VARIABLE,
+ QUERY_VARIABLE_INFO,
+ GET_NEXT_HIGH_MONO_COUNT,
+ UPDATE_CAPSULE,
+ QUERY_CAPSULE_CAPS,
+};
+
+/*
+ * efi_runtime_work: Details of EFI Runtime Service work
+ * @arg<1-5>: EFI Runtime Service function arguments
+ * @status: Status of executing EFI Runtime Service
+ * @efi_rts_id: EFI Runtime Service function identifier
+ * @efi_rts_comp: Struct used for handling completions
+ */
+struct efi_runtime_work {
+ void *arg1;
+ void *arg2;
+ void *arg3;
+ void *arg4;
+ void *arg5;
+ efi_status_t status;
+ struct work_struct work;
+ enum efi_rts_ids efi_rts_id;
+ struct completion efi_rts_comp;
+};
+
+/*
+ * efi_queue_work: Queue efi_runtime_service() and wait until it's done
+ * @rts: efi_runtime_service() function identifier
+ * @rts_arg<1-5>: efi_runtime_service() function arguments
+ *
+ * Accesses to efi_runtime_services() are serialized by a binary
+ * semaphore (efi_runtime_lock) and caller waits until the work is
+ * finished, hence _only_ one work is queued at a time and the caller
+ * thread waits for completion.
+ */
+#define efi_queue_work(_rts, _arg1, _arg2, _arg3, _arg4, _arg5) \
+({ \
+ struct efi_runtime_work efi_rts_work; \
+ efi_rts_work.status = EFI_ABORTED; \
+ \
+ init_completion(&efi_rts_work.efi_rts_comp); \
+ INIT_WORK_ONSTACK(&efi_rts_work.work, efi_call_rts); \
+ efi_rts_work.arg1 = _arg1; \
+ efi_rts_work.arg2 = _arg2; \
+ efi_rts_work.arg3 = _arg3; \
+ efi_rts_work.arg4 = _arg4; \
+ efi_rts_work.arg5 = _arg5; \
+ efi_rts_work.efi_rts_id = _rts; \
+ \
+ /* \
+ * queue_work() returns 0 if work was already on queue, \
+ * _ideally_ this should never happen. \
+ */ \
+ if (queue_work(efi_rts_wq, &efi_rts_work.work)) \
+ wait_for_completion(&efi_rts_work.efi_rts_comp); \
+ else \
+ pr_err("Failed to queue work to efi_rts_wq.\n"); \
+ \
+ efi_rts_work.status; \
+})
+
+void efi_call_virt_check_flags(unsigned long flags, const char *call)
+{
+ unsigned long cur_flags, mismatch;
+
+ local_save_flags(cur_flags);
+
+ mismatch = flags ^ cur_flags;
+ if (!WARN_ON_ONCE(mismatch & ARCH_EFI_IRQ_FLAGS_MASK))
+ return;
+
+ add_taint(TAINT_FIRMWARE_WORKAROUND, LOCKDEP_NOW_UNRELIABLE);
+ pr_err_ratelimited(FW_BUG "IRQ flags corrupted (0x%08lx=>0x%08lx) by EFI %s\n",
+ flags, cur_flags, call);
+ local_irq_restore(flags);
+}
+
+/*
+ * According to section 7.1 of the UEFI spec, Runtime Services are not fully
+ * reentrant, and there are particular combinations of calls that need to be
+ * serialized. (source: UEFI Specification v2.4A)
+ *
+ * Table 31. Rules for Reentry Into Runtime Services
+ * +------------------------------------+-------------------------------+
+ * | If previous call is busy in | Forbidden to call |
+ * +------------------------------------+-------------------------------+
+ * | Any | SetVirtualAddressMap() |
+ * +------------------------------------+-------------------------------+
+ * | ConvertPointer() | ConvertPointer() |
+ * +------------------------------------+-------------------------------+
+ * | SetVariable() | ResetSystem() |
+ * | UpdateCapsule() | |
+ * | SetTime() | |
+ * | SetWakeupTime() | |
+ * | GetNextHighMonotonicCount() | |
+ * +------------------------------------+-------------------------------+
+ * | GetVariable() | GetVariable() |
+ * | GetNextVariableName() | GetNextVariableName() |
+ * | SetVariable() | SetVariable() |
+ * | QueryVariableInfo() | QueryVariableInfo() |
+ * | UpdateCapsule() | UpdateCapsule() |
+ * | QueryCapsuleCapabilities() | QueryCapsuleCapabilities() |
+ * | GetNextHighMonotonicCount() | GetNextHighMonotonicCount() |
+ * +------------------------------------+-------------------------------+
+ * | GetTime() | GetTime() |
+ * | SetTime() | SetTime() |
+ * | GetWakeupTime() | GetWakeupTime() |
+ * | SetWakeupTime() | SetWakeupTime() |
+ * +------------------------------------+-------------------------------+
+ *
+ * Due to the fact that the EFI pstore may write to the variable store in
+ * interrupt context, we need to use a lock for at least the groups that
+ * contain SetVariable() and QueryVariableInfo(). That leaves little else, as
+ * none of the remaining functions are actually ever called at runtime.
+ * So let's just use a single lock to serialize all Runtime Services calls.
+ */
+static DEFINE_SEMAPHORE(efi_runtime_lock);
+
+/*
+ * Calls the appropriate efi_runtime_service() with the appropriate
+ * arguments.
+ *
+ * Semantics followed by efi_call_rts() to understand efi_runtime_work:
+ * 1. If argument was a pointer, recast it from void pointer to original
+ * pointer type.
+ * 2. If argument was a value, recast it from void pointer to original
+ * pointer type and dereference it.
+ */
+static void efi_call_rts(struct work_struct *work)
+{
+ struct efi_runtime_work *efi_rts_work;
+ void *arg1, *arg2, *arg3, *arg4, *arg5;
+ efi_status_t status = EFI_NOT_FOUND;
+
+ efi_rts_work = container_of(work, struct efi_runtime_work, work);
+ arg1 = efi_rts_work->arg1;
+ arg2 = efi_rts_work->arg2;
+ arg3 = efi_rts_work->arg3;
+ arg4 = efi_rts_work->arg4;
+ arg5 = efi_rts_work->arg5;
+
+ switch (efi_rts_work->efi_rts_id) {
+ case GET_TIME:
+ status = efi_call_virt(get_time, (efi_time_t *)arg1,
+ (efi_time_cap_t *)arg2);
+ break;
+ case SET_TIME:
+ status = efi_call_virt(set_time, (efi_time_t *)arg1);
+ break;
+ case GET_WAKEUP_TIME:
+ status = efi_call_virt(get_wakeup_time, (efi_bool_t *)arg1,
+ (efi_bool_t *)arg2, (efi_time_t *)arg3);
+ break;
+ case SET_WAKEUP_TIME:
+ status = efi_call_virt(set_wakeup_time, *(efi_bool_t *)arg1,
+ (efi_time_t *)arg2);
+ break;
+ case GET_VARIABLE:
+ status = efi_call_virt(get_variable, (efi_char16_t *)arg1,
+ (efi_guid_t *)arg2, (u32 *)arg3,
+ (unsigned long *)arg4, (void *)arg5);
+ break;
+ case GET_NEXT_VARIABLE:
+ status = efi_call_virt(get_next_variable, (unsigned long *)arg1,
+ (efi_char16_t *)arg2,
+ (efi_guid_t *)arg3);
+ break;
+ case SET_VARIABLE:
+ status = efi_call_virt(set_variable, (efi_char16_t *)arg1,
+ (efi_guid_t *)arg2, *(u32 *)arg3,
+ *(unsigned long *)arg4, (void *)arg5);
+ break;
+ case QUERY_VARIABLE_INFO:
+ status = efi_call_virt(query_variable_info, *(u32 *)arg1,
+ (u64 *)arg2, (u64 *)arg3, (u64 *)arg4);
+ break;
+ case GET_NEXT_HIGH_MONO_COUNT:
+ status = efi_call_virt(get_next_high_mono_count, (u32 *)arg1);
+ break;
+ case UPDATE_CAPSULE:
+ status = efi_call_virt(update_capsule,
+ (efi_capsule_header_t **)arg1,
+ *(unsigned long *)arg2,
+ *(unsigned long *)arg3);
+ break;
+ case QUERY_CAPSULE_CAPS:
+ status = efi_call_virt(query_capsule_caps,
+ (efi_capsule_header_t **)arg1,
+ *(unsigned long *)arg2, (u64 *)arg3,
+ (int *)arg4);
+ break;
+ default:
+ /*
+ * Ideally, we should never reach here because a caller of this
+ * function should have put the right efi_runtime_service()
+ * function identifier into efi_rts_work->efi_rts_id
+ */
+ pr_err("Requested executing invalid EFI Runtime Service.\n");
+ }
+ efi_rts_work->status = status;
+ complete(&efi_rts_work->efi_rts_comp);
+}
+
+static efi_status_t virt_efi_get_time(efi_time_t *tm, efi_time_cap_t *tc)
+{
+ efi_status_t status;
+
+ if (down_interruptible(&efi_runtime_lock))
+ return EFI_ABORTED;
+ status = efi_queue_work(GET_TIME, tm, tc, NULL, NULL, NULL);
+ up(&efi_runtime_lock);
+ return status;
+}
+
+static efi_status_t virt_efi_set_time(efi_time_t *tm)
+{
+ efi_status_t status;
+
+ if (down_interruptible(&efi_runtime_lock))
+ return EFI_ABORTED;
+ status = efi_queue_work(SET_TIME, tm, NULL, NULL, NULL, NULL);
+ up(&efi_runtime_lock);
+ return status;
+}
+
+static efi_status_t virt_efi_get_wakeup_time(efi_bool_t *enabled,
+ efi_bool_t *pending,
+ efi_time_t *tm)
+{
+ efi_status_t status;
+
+ if (down_interruptible(&efi_runtime_lock))
+ return EFI_ABORTED;
+ status = efi_queue_work(GET_WAKEUP_TIME, enabled, pending, tm, NULL,
+ NULL);
+ up(&efi_runtime_lock);
+ return status;
+}
+
+static efi_status_t virt_efi_set_wakeup_time(efi_bool_t enabled, efi_time_t *tm)
+{
+ efi_status_t status;
+
+ if (down_interruptible(&efi_runtime_lock))
+ return EFI_ABORTED;
+ status = efi_queue_work(SET_WAKEUP_TIME, &enabled, tm, NULL, NULL,
+ NULL);
+ up(&efi_runtime_lock);
+ return status;
+}
+
+static efi_status_t virt_efi_get_variable(efi_char16_t *name,
+ efi_guid_t *vendor,
+ u32 *attr,
+ unsigned long *data_size,
+ void *data)
+{
+ efi_status_t status;
+
+ if (down_interruptible(&efi_runtime_lock))
+ return EFI_ABORTED;
+ status = efi_queue_work(GET_VARIABLE, name, vendor, attr, data_size,
+ data);
+ up(&efi_runtime_lock);
+ return status;
+}
+
+static efi_status_t virt_efi_get_next_variable(unsigned long *name_size,
+ efi_char16_t *name,
+ efi_guid_t *vendor)
+{
+ efi_status_t status;
+
+ if (down_interruptible(&efi_runtime_lock))
+ return EFI_ABORTED;
+ status = efi_queue_work(GET_NEXT_VARIABLE, name_size, name, vendor,
+ NULL, NULL);
+ up(&efi_runtime_lock);
+ return status;
+}
+
+static efi_status_t virt_efi_set_variable(efi_char16_t *name,
+ efi_guid_t *vendor,
+ u32 attr,
+ unsigned long data_size,
+ void *data)
+{
+ efi_status_t status;
+
+ if (down_interruptible(&efi_runtime_lock))
+ return EFI_ABORTED;
+ status = efi_queue_work(SET_VARIABLE, name, vendor, &attr, &data_size,
+ data);
+ up(&efi_runtime_lock);
+ return status;
+}
+
+static efi_status_t
+virt_efi_set_variable_nonblocking(efi_char16_t *name, efi_guid_t *vendor,
+ u32 attr, unsigned long data_size,
+ void *data)
+{
+ efi_status_t status;
+
+ if (down_trylock(&efi_runtime_lock))
+ return EFI_NOT_READY;
+
+ status = efi_call_virt(set_variable, name, vendor, attr, data_size,
+ data);
+ up(&efi_runtime_lock);
+ return status;
+}
+
+
+static efi_status_t virt_efi_query_variable_info(u32 attr,
+ u64 *storage_space,
+ u64 *remaining_space,
+ u64 *max_variable_size)
+{
+ efi_status_t status;
+
+ if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
+ return EFI_UNSUPPORTED;
+
+ if (down_interruptible(&efi_runtime_lock))
+ return EFI_ABORTED;
+ status = efi_queue_work(QUERY_VARIABLE_INFO, &attr, storage_space,
+ remaining_space, max_variable_size, NULL);
+ up(&efi_runtime_lock);
+ return status;
+}
+
+static efi_status_t
+virt_efi_query_variable_info_nonblocking(u32 attr,
+ u64 *storage_space,
+ u64 *remaining_space,
+ u64 *max_variable_size)
+{
+ efi_status_t status;
+
+ if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
+ return EFI_UNSUPPORTED;
+
+ if (down_trylock(&efi_runtime_lock))
+ return EFI_NOT_READY;
+
+ status = efi_call_virt(query_variable_info, attr, storage_space,
+ remaining_space, max_variable_size);
+ up(&efi_runtime_lock);
+ return status;
+}
+
+static efi_status_t virt_efi_get_next_high_mono_count(u32 *count)
+{
+ efi_status_t status;
+
+ if (down_interruptible(&efi_runtime_lock))
+ return EFI_ABORTED;
+ status = efi_queue_work(GET_NEXT_HIGH_MONO_COUNT, count, NULL, NULL,
+ NULL, NULL);
+ up(&efi_runtime_lock);
+ return status;
+}
+
+static void virt_efi_reset_system(int reset_type,
+ efi_status_t status,
+ unsigned long data_size,
+ efi_char16_t *data)
+{
+ if (down_interruptible(&efi_runtime_lock)) {
+ pr_warn("failed to invoke the reset_system() runtime service:\n"
+ "could not get exclusive access to the firmware\n");
+ return;
+ }
+ __efi_call_virt(reset_system, reset_type, status, data_size, data);
+ up(&efi_runtime_lock);
+}
+
+static efi_status_t virt_efi_update_capsule(efi_capsule_header_t **capsules,
+ unsigned long count,
+ unsigned long sg_list)
+{
+ efi_status_t status;
+
+ if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
+ return EFI_UNSUPPORTED;
+
+ if (down_interruptible(&efi_runtime_lock))
+ return EFI_ABORTED;
+ status = efi_queue_work(UPDATE_CAPSULE, capsules, &count, &sg_list,
+ NULL, NULL);
+ up(&efi_runtime_lock);
+ return status;
+}
+
+static efi_status_t virt_efi_query_capsule_caps(efi_capsule_header_t **capsules,
+ unsigned long count,
+ u64 *max_size,
+ int *reset_type)
+{
+ efi_status_t status;
+
+ if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
+ return EFI_UNSUPPORTED;
+
+ if (down_interruptible(&efi_runtime_lock))
+ return EFI_ABORTED;
+ status = efi_queue_work(QUERY_CAPSULE_CAPS, capsules, &count,
+ max_size, reset_type, NULL);
+ up(&efi_runtime_lock);
+ return status;
+}
+
+void efi_native_runtime_setup(void)
+{
+ efi.get_time = virt_efi_get_time;
+ efi.set_time = virt_efi_set_time;
+ efi.get_wakeup_time = virt_efi_get_wakeup_time;
+ efi.set_wakeup_time = virt_efi_set_wakeup_time;
+ efi.get_variable = virt_efi_get_variable;
+ efi.get_next_variable = virt_efi_get_next_variable;
+ efi.set_variable = virt_efi_set_variable;
+ efi.set_variable_nonblocking = virt_efi_set_variable_nonblocking;
+ efi.get_next_high_mono_count = virt_efi_get_next_high_mono_count;
+ efi.reset_system = virt_efi_reset_system;
+ efi.query_variable_info = virt_efi_query_variable_info;
+ efi.query_variable_info_nonblocking = virt_efi_query_variable_info_nonblocking;
+ efi.update_capsule = virt_efi_update_capsule;
+ efi.query_capsule_caps = virt_efi_query_capsule_caps;
+}