Re: [U-Boot] [PATCH v1 05/15] efi_loader: add device-path utils

On 08/10/2017 08:29 PM, Rob Clark wrote:

Helpers to construct device-paths from devices, partitions, files, and for parsing and manipulating device-paths.

For non-legacy devices, this will use u-boot's device-model to construct device-paths which include bus hierarchy to construct device-paths. For legacy devices we still fake it, but slightly more convincingly.

Signed-off-by: Rob Clark robdclark@gmail.com

include/efi_api.h | 10 + include/efi_loader.h | 20 ++ lib/efi_loader/Makefile | 2 +- lib/efi_loader/efi_device_path.c | 489 +++++++++++++++++++++++++++++++++++++++ 4 files changed, 520 insertions(+), 1 deletion(-) create mode 100644 lib/efi_loader/efi_device_path.c

diff --git a/include/efi_api.h b/include/efi_api.h index b761cf4822..4e27c82129 100644 --- a/include/efi_api.h +++ b/include/efi_api.h @@ -314,6 +314,7 @@ struct efi_device_path_acpi_path { #define DEVICE_PATH_TYPE_MESSAGING_DEVICE 0x03 # define DEVICE_PATH_SUB_TYPE_MSG_USB 0x05 # define DEVICE_PATH_SUB_TYPE_MSG_MAC_ADDR 0x0b +# define DEVICE_PATH_SUB_TYPE_MSG_USB_CLASS 0x0f # define DEVICE_PATH_SUB_TYPE_MSG_SD 0x1a # define DEVICE_PATH_SUB_TYPE_MSG_MMC 0x1d

@@ -329,6 +330,15 @@ struct efi_device_path_mac_addr { u8 if_type; } __packed;

+struct efi_device_path_usb_class {

• struct efi_device_path dp;
• u16 vendor_id;
• u16 product_id;
• u8 device_class;
• u8 device_subclass;
• u8 device_protocol;

+} __packed;

struct efi_device_path_sd_mmc_path { struct efi_device_path dp; u8 slot_number; diff --git a/include/efi_loader.h b/include/efi_loader.h index 037cc7c543..bcca6e49ea 100644 --- a/include/efi_loader.h +++ b/include/efi_loader.h @@ -197,6 +197,26 @@ extern void *efi_bounce_buffer; #define EFI_LOADER_BOUNCE_BUFFER_SIZE (64 * 1024 * 1024) #endif

+struct efi_device_path *efi_dp_next(struct efi_device_path *dp); +int efi_dp_match(struct efi_device_path *a, struct efi_device_path *b); +struct efi_object *efi_dp_find_obj(struct efi_device_path *dp); +unsigned efi_dp_size(struct efi_device_path *dp); +struct efi_device_path *efi_dp_dup(struct efi_device_path *dp);

+struct efi_device_path *efi_dp_from_dev(struct udevice *dev); +struct efi_device_path *efi_dp_from_part(struct blk_desc *desc, int part); +struct efi_device_path *efi_dp_from_file(struct blk_desc *desc, int part,

• 			 const char *path);
  

+struct efi_device_path *efi_dp_from_eth(void); +void efi_dp_split_file_path(struct efi_device_path *full_path,

• 	    struct efi_device_path **device_path,
  

• 	    struct efi_device_path **file_path);
  

+#define EFI_DP_TYPE(_dp, _type, _subtype) \

• (((_dp)->type == DEVICE_PATH_TYPE_##_type) && \

• ((_dp)->sub_type == DEVICE_PATH_SUB_TYPE_##_subtype))
  

/* Convert strings from normal C strings to uEFI strings */ static inline void ascii2unicode(u16 *unicode, const char *ascii) { diff --git a/lib/efi_loader/Makefile b/lib/efi_loader/Makefile index 30bf343a36..f35e5ce8a8 100644 --- a/lib/efi_loader/Makefile +++ b/lib/efi_loader/Makefile @@ -15,7 +15,7 @@ always := $(efiprogs-y)

obj-$(CONFIG_CMD_BOOTEFI_HELLO) += helloworld_efi.o obj-y += efi_image_loader.o efi_boottime.o efi_runtime.o efi_console.o -obj-y += efi_memory.o efi_device_path_to_text.o +obj-y += efi_memory.o efi_device_path_to_text.o efi_device_path.o obj-$(CONFIG_LCD) += efi_gop.o obj-$(CONFIG_DM_VIDEO) += efi_gop.o obj-$(CONFIG_PARTITIONS) += efi_disk.o diff --git a/lib/efi_loader/efi_device_path.c b/lib/efi_loader/efi_device_path.c new file mode 100644 index 0000000000..e8a6bbff82 --- /dev/null +++ b/lib/efi_loader/efi_device_path.c @@ -0,0 +1,489 @@ +/*

• • EFI device path from u-boot device-model mapping
• • (C) Copyright 2017 Rob Clark
• • SPDX-License-Identifier: GPL-2.0+
• */

+#include <common.h> +#include <blk.h> +#include <dm.h> +#include <usb.h> +#include <mmc.h> +#include <efi_loader.h> +#include <inttypes.h> +#include <part.h> +#include <malloc.h>

+/* template END node: */ +static const struct efi_device_path END = {

• .type = DEVICE_PATH_TYPE_END,
• .sub_type = DEVICE_PATH_SUB_TYPE_END,
• .length = sizeof(END),

+};

+#define U_BOOT_GUID \

• EFI_GUID(0xe61d73b9, 0xa384, 0x4acc, \

•  0xae, 0xab, 0x82, 0xe8, 0x28, 0xf3, 0x62, 0x8b)
  

+/* template ROOT node, a fictional ACPI PNP device: */ +static const struct efi_device_path_vendor ROOT = {

• .dp = {

• .type     = DEVICE_PATH_TYPE_HARDWARE_DEVICE,
  

• .sub_type = DEVICE_PATH_SUB_TYPE_VENDOR,
  

• .length   = sizeof(ROOT),
  

• },
• .guid = U_BOOT_GUID,

+};

+/*

• • Iterate to next block in device-path, terminating (returning NULL)
• • at /End* node.
• */

+struct efi_device_path *efi_dp_next(struct efi_device_path *dp) +{

• if (dp == NULL)

• return NULL;
  

• dp = ((void *)dp) + dp->length;
• if (dp->type == DEVICE_PATH_TYPE_END)

• return NULL;
  

• return dp;

+}

+/*

• • Compare two device-paths, stopping when the shorter of the two hits
• • an End* node. This is useful to, for example, compare a device-path
• • representing a device with one representing a file on the device, or
• • a device with a parent device.
• */

+int efi_dp_match(struct efi_device_path *a, struct efi_device_path *b) +{

• while (1) {

• int ret;
  

• ret = memcmp(&a->length, &b->length, sizeof(a->length));
  

• if (ret)
  

• 	return ret;
  

• ret = memcmp(a, b, a->length);
  

• if (ret)
  

• 	return ret;
  

• a = efi_dp_next(a);
  

• b = efi_dp_next(b);
  

• if (!a || !b)
  

• 	return 0;
  

• }

+}

+/*

• • See UEFI spec (section 3.1.2, about short-form device-paths..
• • tl;dr: we can have a device-path that starts with a USB WWID
• • or USB Class node, and a few other cases which don't encode
• • the full device path with bus hierarchy:
• • • MESSAGING:USB_WWID
• • • MESSAGING:USB_CLASS
• • • MEDIA:FILE_PATH
• • • MEDIA:HARD_DRIVE
• • • MESSAGING:URI
• */

+static struct efi_device_path *shorten_path(struct efi_device_path *dp) +{

• while (dp) {

• /*
  

•  * TODO: Add MESSAGING:USB_WWID and MESSAGING:URI..
  

•  * in practice fallback.efi just uses MEDIA:HARD_DRIVE
  

•  * so not sure when we would see these other cases.
  

•  */
  

• if (EFI_DP_TYPE(dp, MESSAGING_DEVICE, MSG_USB_CLASS) ||
  

•     EFI_DP_TYPE(dp, MEDIA_DEVICE, HARD_DRIVE_PATH) ||
  

•     EFI_DP_TYPE(dp, MEDIA_DEVICE, FILE_PATH))
  

• 	return dp;
  

• dp = efi_dp_next(dp);
  

• }
• return dp;

+}

+static struct efi_object *find_obj(struct efi_device_path *dp, bool short_path) +{

• struct efi_object *efiobj;
• list_for_each_entry(efiobj, &efi_obj_list, link) {

• int i;
  

• for (i = 0; i < ARRAY_SIZE(efiobj->protocols); i++) {
  

• 	struct efi_handler *handler = &efiobj->protocols[i];
  

• 	struct efi_device_path *obj_dp;
  

• 	if (!handler->guid)
  

• 		break;
  

• 	if (guidcmp(handler->guid, &efi_guid_device_path))
  

• 		continue;
  

• 	obj_dp = handler->protocol_interface;
  

• 	do {
  

• 		if (efi_dp_match(dp, obj_dp) == 0)
  

• 			return efiobj;
  

• 		obj_dp = shorten_path(efi_dp_next(obj_dp));
  

• 	} while (short_path && obj_dp);
  

• }
  

• }
• return NULL;

+}

+/* Find an efiobj from device-path */ +struct efi_object *efi_dp_find_obj(struct efi_device_path *dp) +{

• struct efi_object *efiobj;
• efiobj = find_obj(dp, false);
• if (!efiobj)

• efiobj = find_obj(dp, true);
  

• return efiobj;

+}

+/* return size not including End node: */ +unsigned efi_dp_size(struct efi_device_path *dp) +{

• unsigned sz = 0;
• while (dp) {

• sz += dp->length;
  

• dp = efi_dp_next(dp);
  

• }
• return sz;

+}

+struct efi_device_path *efi_dp_dup(struct efi_device_path *dp) +{

• struct efi_device_path *ndp;
• unsigned sz = efi_dp_size(dp) + sizeof(struct efi_device_path);
• ndp = malloc(sz);
• memcpy(ndp, dp, sz);
• return ndp;

+}

+#ifdef CONFIG_DM +/* size of device-path not including END node for device and all parents

• • up to the root device.
• */

+static unsigned dp_size(struct udevice *dev) +{

• if (!dev || !dev->driver)

• return sizeof(ROOT);
  

• switch (dev->driver->id) {
• case UCLASS_ROOT:
• case UCLASS_SIMPLE_BUS:

• /* stop traversing parents at this point: */
  

• return sizeof(ROOT);
  

• case UCLASS_MMC:

• return dp_size(dev->parent) + sizeof(struct efi_device_path_sd_mmc_path);
  

• case UCLASS_MASS_STORAGE:
• case UCLASS_USB_HUB:

• return dp_size(dev->parent) + sizeof(struct efi_device_path_usb_class);
  

It seems you forgot to run scripts/checkpatch.pl for your patches:

Line over 80 characters. Please, use line break.

• default:

• /* just skip over unknown classes: */
  

• return dp_size(dev->parent);
  

• }

+}

+static void *dp_fill(void *buf, struct udevice *dev) +{

• if (!dev || !dev->driver)

• return buf;
  

• switch (dev->driver->id) {
• case UCLASS_ROOT:
• case UCLASS_SIMPLE_BUS: {

• /* stop traversing parents at this point: */
  

• struct efi_device_path_vendor *vdp = buf;
  

• *vdp = ROOT;
  

• return &vdp[1];
  

• }

+#if defined(CONFIG_DM_MMC) && defined (CONFIG_MMC)

scripts/checkpatch.pl: WARNING: space prohibited between function name and open parenthesis '('

• case UCLASS_MMC: {

• struct efi_device_path_sd_mmc_path *sddp =
  

• 	dp_fill(buf, dev->parent);
  

• struct mmc *mmc = mmc_get_mmc_dev(dev);
  

• struct blk_desc *desc = mmc_get_blk_desc(mmc);
  

• sddp->dp.type     = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
  

• sddp->dp.sub_type = (desc->if_type == IF_TYPE_MMC) ?
  

• 	DEVICE_PATH_SUB_TYPE_MSG_MMC :
  

• 	DEVICE_PATH_SUB_TYPE_MSG_SD;
  

• sddp->dp.length   = sizeof(*sddp);
  

• sddp->slot_number = 0;  // XXX ???
  

• return &sddp[1];
  

• }

+#endif

• case UCLASS_MASS_STORAGE:
• case UCLASS_USB_HUB: {

• struct efi_device_path_usb_class *udp =
  

• 	dp_fill(buf, dev->parent);
  

• struct usb_device *udev = dev_get_parent_priv(dev);
  

• struct usb_device_descriptor *desc = &udev->descriptor;
  

• udp->dp.type     = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
  

• udp->dp.sub_type = DEVICE_PATH_SUB_TYPE_MSG_USB_CLASS;
  

• udp->dp.length   = sizeof(*udp);
  

• udp->vendor_id   = desc->idVendor;
  

• udp->product_id  = desc->idProduct;
  

• udp->device_class    = desc->bDeviceClass;
  

• udp->device_subclass = desc->bDeviceSubClass;
  

• udp->device_protocol = desc->bDeviceProtocol;
  

• return &udp[1];
  

• }
• default:

• debug("unhandled device class: %s (%u)\n",
  

• 	dev->name, dev->driver->id);
  

scripts/checkpatch.pl: Alignment should match open parenthesis

• return dp_fill(buf, dev->parent);
  

• }

+}

+/* Construct a device-path from a device: */ +struct efi_device_path *efi_dp_from_dev(struct udevice *dev) +{

• void *buf, *start;
• start = buf = calloc(1, dp_size(dev) + sizeof(END));
• buf = dp_fill(buf, dev);
• *((struct efi_device_path *)buf) = END;
• return start;

+} +#endif

+static unsigned dp_part_size(struct blk_desc *desc, int part) +{

• unsigned dpsize;

+#ifdef CONFIG_BLK

• dpsize = dp_size(desc->bdev->parent);

+#else

• dpsize = sizeof(ROOT) + sizeof(struct efi_device_path_usb);

+#endif

• if (part == 0) /* the actual disk, not a partition */

• return dpsize;
  

• if (desc->part_type == PART_TYPE_ISO) {

• dpsize += sizeof(struct efi_device_path_cdrom_path);
  

• } else {

• dpsize += sizeof(struct efi_device_path_hard_drive_path);
  

• }

Please, have a look at all warnings produced by scripts/checkpatch.pl. Here you get:

WARNING: braces {} are not necessary for any arm of this statement #464: FILE: lib/efi_loader/efi_device_path.c:289: + if (desc->part_type == PART_TYPE_ISO) { [...] + } else { [...]

Best regards

Heinrich

• return dpsize;

+}

+static void *dp_part_fill(void *buf, struct blk_desc *desc, int part) +{

• disk_partition_t info;

+#ifdef CONFIG_BLK

• buf = dp_fill(buf, desc->bdev->parent);

+#else

• /*

• * We *could* make a more accurate path, by looking at if_type
  

• * and handling all the different cases like we do for non-
  

• * legacy (ie CONFIG_BLK=y) case.  But most important thing
  

• * is just to have a unique device-path for if_type+devnum.
  

• * So map things to a fictional USB device:
  

• */
  

• struct efi_device_path_usb *udp;
• memcpy(buf, &ROOT, sizeof(ROOT));
• buf += sizeof(ROOT);
• udp = buf;
• udp->dp.type = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
• udp->dp.sub_type = DEVICE_PATH_SUB_TYPE_MSG_USB;
• udp->dp.length = sizeof(*udp);
• udp->parent_port_number = desc->if_type;
• udp->usb_interface = desc->devnum;
• buf = &udp[1];

+#endif

• if (part == 0) /* the actual disk, not a partition */

• return buf;
  

• part_get_info(desc, part, &info);
• if (desc->part_type == PART_TYPE_ISO) {

• struct efi_device_path_cdrom_path *cddp = buf;
  

• cddp->boot_entry = part - 1;
  

• cddp->dp.type = DEVICE_PATH_TYPE_MEDIA_DEVICE;
  

• cddp->dp.sub_type = DEVICE_PATH_SUB_TYPE_CDROM_PATH;
  

• cddp->dp.length = sizeof (*cddp);
  

• cddp->partition_start = info.start;
  

• cddp->partition_end = info.size;
  

• buf = &cddp[1];
  

• } else {

• struct efi_device_path_hard_drive_path *hddp = buf;
  

• hddp->dp.type = DEVICE_PATH_TYPE_MEDIA_DEVICE;
  

• hddp->dp.sub_type = DEVICE_PATH_SUB_TYPE_HARD_DRIVE_PATH;
  

• hddp->dp.length = sizeof (*hddp);
  

• hddp->partition_number = part - 1;
  

• hddp->partition_start = info.start;
  

• hddp->partition_end = info.size;
  

• if (desc->part_type == PART_TYPE_EFI)
  

• 	hddp->partmap_type = 2;
  

• else
  

• 	hddp->partmap_type = 1;
  

• hddp->signature_type = desc->sig_type;
  

• if (hddp->signature_type != 0)
  

• 	memcpy(hddp->partition_signature, &desc->guid_sig,
  

• 	       sizeof(hddp->partition_signature));
  

• buf = &hddp[1];
  

• }
• return buf;

+}

+/* Construct a device-path from a partition on a blk device: */ +struct efi_device_path *efi_dp_from_part(struct blk_desc *desc, int part) +{

• void *buf, *start;
• start = buf = calloc(1, dp_part_size(desc, part) + sizeof(END));
• buf = dp_part_fill(buf, desc, part);
• *((struct efi_device_path *)buf) = END;
• return start;

+}

+/* convert path to an UEFI style path (ie. DOS style backslashes and utf16) */ +static void path_to_uefi(u16 *uefi, const char *path) +{

• while (*path) {

• char c = *(path++);
  

• if (c == '/')
  

• 	c = '\\';
  

• *(uefi++) = c;
  

• }
• *uefi = '\0';

+}

+/*

• • If desc is NULL, this creates a path with only the file component,
• • otherwise it creates a full path with both device and file components
• */

+struct efi_device_path *efi_dp_from_file(struct blk_desc *desc, int part,

• const char *path)
  

+{

• struct efi_device_path_file_path *fp;
• void *buf, *start;
• unsigned dpsize = 0, fpsize;
• if (desc)

• dpsize = dp_part_size(desc, part);
  

• // TODO efi_device_path_file_path should be variable length:
• fpsize = sizeof(struct efi_device_path) + 2 * (strlen(path) + 1);
• dpsize += fpsize;
• start = buf = calloc(1, dpsize + sizeof(END));
• if (desc)

• buf = dp_part_fill(buf, desc, part);
  

• /* add file-path: */
• fp = buf;
• fp->dp.type = DEVICE_PATH_TYPE_MEDIA_DEVICE;
• fp->dp.sub_type = DEVICE_PATH_SUB_TYPE_FILE_PATH;
• fp->dp.length = fpsize;
• path_to_uefi(fp->str, path);
• buf += fpsize;
• *((struct efi_device_path *)buf) = END;
• return start;

+}

+#ifdef CONFIG_NET +struct efi_device_path *efi_dp_from_eth(void) +{

• struct efi_device_path_mac_addr *ndp;
• void *buf, *start;
• unsigned dpsize = 0;
• assert(eth_get_dev());

+#ifdef CONFIG_DM_ETH

• dpsize += dp_size(eth_get_dev());

+#else

• dpsize += sizeof(ROOT);

+#endif

• dpsize += sizeof(*ndp);
• start = buf = calloc(1, dpsize + sizeof(END));

+#ifdef CONFIG_DM_ETH

• buf = dp_fill(buf, eth_get_dev());

+#else

• memcpy(buf, &ROOT, sizeof(ROOT));
• buf += sizeof(ROOT);

+#endif

• ndp = buf;
• ndp->dp.type = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
• ndp->dp.sub_type = DEVICE_PATH_SUB_TYPE_MSG_MAC_ADDR;
• ndp->dp.length = sizeof(*ndp);
• memcpy(ndp->mac.addr, eth_get_ethaddr(), ARP_HLEN);
• buf = &ndp[1];
• *((struct efi_device_path *)buf) = END;
• return start;

+} +#endif

+/*

• • Helper to split a full device path (containing both device and file
• • parts) into it's constituent parts.
• */

+void efi_dp_split_file_path(struct efi_device_path *full_path,

• 	    struct efi_device_path **device_path,
  

• 	    struct efi_device_path **file_path)
  

+{

• struct efi_device_path *p, *dp, *fp;
• dp = efi_dp_dup(full_path);
• p = dp;
• while (!EFI_DP_TYPE(p, MEDIA_DEVICE, FILE_PATH))

• p = efi_dp_next(p);
  

• fp = efi_dp_dup(p);
• p->type = DEVICE_PATH_TYPE_END;
• p->sub_type = DEVICE_PATH_SUB_TYPE_END;
• p->length = sizeof(*p);
• *device_path = dp;
• *file_path = fp;

+}