From 32f4b2f8c455b70cea65f5ba63346a6efc9d4e1e Mon Sep 17 00:00:00 2001 From: Heinrich Schuchardt Date: Fri, 15 Sep 2017 10:06:16 +0200 Subject: [PATCH] efi_loader: implement task priority level (TPL) Define variable holding tpl. Implement RaiseTPL and RestoreTPL. Implement TPL check in efi_signal_event. Implement TPL check in efi_wait_for_event. Signed-off-by: Heinrich Schuchardt Signed-off-by: Alexander Graf --- lib/efi_loader/efi_boottime.c | 32 ++++++++++++++++++++++++++++---- 1 file changed, 28 insertions(+), 4 deletions(-) diff --git a/lib/efi_loader/efi_boottime.c b/lib/efi_loader/efi_boottime.c index 73793cd986..7c92a68bf4 100644 --- a/lib/efi_loader/efi_boottime.c +++ b/lib/efi_loader/efi_boottime.c @@ -18,6 +18,9 @@ DECLARE_GLOBAL_DATA_PTR; +/* Task priority level */ +static UINTN efi_tpl = TPL_APPLICATION; + /* This list contains all the EFI objects our payload has access to */ LIST_HEAD(efi_obj_list); @@ -161,7 +164,9 @@ void efi_signal_event(struct efi_event *event) { if (event->notify_function) { event->queued = 1; - /* Put missing TPL check here */ + /* Check TPL */ + if (efi_tpl >= event->notify_tpl) + return; EFI_CALL_VOID(event->notify_function(event, event->notify_context)); } @@ -176,14 +181,31 @@ static efi_status_t efi_unsupported(const char *funcname) static unsigned long EFIAPI efi_raise_tpl(UINTN new_tpl) { + UINTN old_tpl = efi_tpl; + EFI_ENTRY("0x%zx", new_tpl); - return EFI_EXIT(0); + + if (new_tpl < efi_tpl) + debug("WARNING: new_tpl < current_tpl in %s\n", __func__); + efi_tpl = new_tpl; + if (efi_tpl > TPL_HIGH_LEVEL) + efi_tpl = TPL_HIGH_LEVEL; + + EFI_EXIT(EFI_SUCCESS); + return old_tpl; } static void EFIAPI efi_restore_tpl(UINTN old_tpl) { EFI_ENTRY("0x%zx", old_tpl); - efi_unsupported(__func__); + + if (old_tpl > efi_tpl) + debug("WARNING: old_tpl > current_tpl in %s\n", __func__); + efi_tpl = old_tpl; + if (efi_tpl > TPL_HIGH_LEVEL) + efi_tpl = TPL_HIGH_LEVEL; + + EFI_EXIT(EFI_SUCCESS); } static efi_status_t EFIAPI efi_allocate_pages_ext(int type, int memory_type, @@ -388,7 +410,9 @@ static efi_status_t EFIAPI efi_wait_for_event(unsigned long num_events, /* Check parameters */ if (!num_events || !event) return EFI_EXIT(EFI_INVALID_PARAMETER); - /* Put missing TPL check here */ + /* Check TPL */ + if (efi_tpl != TPL_APPLICATION) + return EFI_EXIT(EFI_UNSUPPORTED); for (i = 0; i < num_events; ++i) { for (j = 0; j < ARRAY_SIZE(efi_events); ++j) { if (event[i] == &efi_events[j]) -- 2.39.5