From 2732ea0d5c0a67ec86bfbde2bd68b6152e23ec4e Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Tue, 24 Dec 2019 16:10:07 +0100 Subject: [PATCH] efi/libstub: Use a helper to iterate over a EFI handle array Iterating over a EFI handle array is a bit finicky, since we have to take mixed mode into account, where handles are only 32-bit while the native efi_handle_t type is 64-bit. So introduce a helper, and replace the various occurrences of this pattern. Signed-off-by: Ard Biesheuvel Cc: Arvind Sankar Cc: Borislav Petkov Cc: James Morse Cc: Matt Fleming Cc: Thomas Gleixner Cc: linux-efi@vger.kernel.org Link: https://lkml.kernel.org/r/20191224151025.32482-8-ardb@kernel.org Signed-off-by: Ingo Molnar --- arch/x86/boot/compressed/eboot.c | 14 +++++--------- drivers/firmware/efi/libstub/gop.c | 9 ++------- include/linux/efi.h | 13 +++++++++++++ 3 files changed, 20 insertions(+), 16 deletions(-) diff --git a/arch/x86/boot/compressed/eboot.c b/arch/x86/boot/compressed/eboot.c index 72b08fde6de6..959bcdd8c1fe 100644 --- a/arch/x86/boot/compressed/eboot.c +++ b/arch/x86/boot/compressed/eboot.c @@ -135,6 +135,7 @@ static void setup_efi_pci(struct boot_params *params) unsigned long size = 0; unsigned long nr_pci; struct setup_data *data; + efi_handle_t h; int i; status = efi_call_early(locate_handle, @@ -164,14 +165,11 @@ static void setup_efi_pci(struct boot_params *params) while (data && data->next) data = (struct setup_data *)(unsigned long)data->next; - nr_pci = size / (efi_is_64bit() ? sizeof(u64) : sizeof(u32)); - for (i = 0; i < nr_pci; i++) { + for_each_efi_handle(h, pci_handle, size, i) { efi_pci_io_protocol_t *pci = NULL; struct pci_setup_rom *rom; - status = efi_call_early(handle_protocol, - efi_is_64bit() ? ((u64 *)pci_handle)[i] - : ((u32 *)pci_handle)[i], + status = efi_call_early(handle_protocol, h, &pci_proto, (void **)&pci); if (status != EFI_SUCCESS || !pci) continue; @@ -266,6 +264,7 @@ setup_uga(struct screen_info *si, efi_guid_t *uga_proto, unsigned long size) void **uga_handle = NULL; efi_uga_draw_protocol_t *uga = NULL, *first_uga; unsigned long nr_ugas; + efi_handle_t handle; int i; status = efi_call_early(allocate_pool, EFI_LOADER_DATA, @@ -283,13 +282,10 @@ setup_uga(struct screen_info *si, efi_guid_t *uga_proto, unsigned long size) width = 0; first_uga = NULL; - nr_ugas = size / (efi_is_64bit() ? sizeof(u64) : sizeof(u32)); - for (i = 0; i < nr_ugas; i++) { + for_each_efi_handle(handle, uga_handle, size, i) { efi_guid_t pciio_proto = EFI_PCI_IO_PROTOCOL_GUID; u32 w, h, depth, refresh; void *pciio; - unsigned long handle = efi_is_64bit() ? ((u64 *)uga_handle)[i] - : ((u32 *)uga_handle)[i]; status = efi_call_early(handle_protocol, handle, uga_proto, (void **)&uga); diff --git a/drivers/firmware/efi/libstub/gop.c b/drivers/firmware/efi/libstub/gop.c index 94045ab7dd3d..5f4fbc2ac687 100644 --- a/drivers/firmware/efi/libstub/gop.c +++ b/drivers/firmware/efi/libstub/gop.c @@ -91,7 +91,6 @@ setup_gop(efi_system_table_t *sys_table_arg, struct screen_info *si, efi_guid_t *proto, unsigned long size, void **handles) { efi_graphics_output_protocol_t *gop, *first_gop; - unsigned long nr_gops; u16 width, height; u32 pixels_per_scan_line; u32 ext_lfb_base; @@ -99,22 +98,18 @@ setup_gop(efi_system_table_t *sys_table_arg, struct screen_info *si, efi_pixel_bitmask_t pixel_info; int pixel_format; efi_status_t status; + efi_handle_t h; int i; - bool is64 = efi_is_64bit(); first_gop = NULL; gop = NULL; - nr_gops = size / (is64 ? sizeof(u64) : sizeof(u32)); - for (i = 0; i < nr_gops; i++) { + for_each_efi_handle(h, handles, size, i) { efi_graphics_output_protocol_mode_t *mode; efi_graphics_output_mode_info_t *info = NULL; efi_guid_t conout_proto = EFI_CONSOLE_OUT_DEVICE_GUID; bool conout_found = false; void *dummy = NULL; - efi_handle_t h = (efi_handle_t)(unsigned long) - (is64 ? ((u64 *)handles)[i] - : ((u32 *)handles)[i]); efi_physical_addr_t current_fb_base; status = efi_call_early(handle_protocol, h, diff --git a/include/linux/efi.h b/include/linux/efi.h index 561db9deedae..8d267715ce22 100644 --- a/include/linux/efi.h +++ b/include/linux/efi.h @@ -48,6 +48,19 @@ typedef u16 efi_char16_t; /* UNICODE character */ typedef u64 efi_physical_addr_t; typedef void *efi_handle_t; +#define efi_get_handle_at(array, idx) \ + (efi_is_64bit() ? (efi_handle_t)(unsigned long)((u64 *)(array))[idx] \ + : (efi_handle_t)(unsigned long)((u32 *)(array))[idx]) + +#define efi_get_handle_num(size) \ + ((size) / (efi_is_64bit() ? sizeof(u64) : sizeof(u32))) + +#define for_each_efi_handle(handle, array, size, i) \ + for (i = 0; \ + i < efi_get_handle_num(size) && \ + ((handle = efi_get_handle_at((array), i)) || true); \ + i++) + /* * The UEFI spec and EDK2 reference implementation both define EFI_GUID as * struct { u32 a; u16; b; u16 c; u8 d[8]; }; and so the implied alignment