efi_loader: Clean up efi_dp_append and efi_dp_concat

Looking back at the initrd storing functionality, we introduced three
functions, efi_dp_append_or_concatenate(), efi_dp_append/concat(). In
hindsight we could have simplified that by a lot. First of all none of
the functions append anything. They all allocate a new device path and
concatenate the contents of two device paths in one. A boolean parameter
controls the final device path -- if that's true an end node is injected
between the two device paths.

So let's rewrite this and make it a bit easier to read. Get rid of
efi_dp_append(), efi_dp_concat() and rename
efi_dp_append_or_concatenate() to efi_dp_concat(). This is far more
intuitive and the only adjustment that is needed is an extra boolean
argument on all callsites.

Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
This commit is contained in:
Ilias Apalodimas 2024-01-08 10:55:33 +02:00 committed by Heinrich Schuchardt
parent 753f76e417
commit f19171c919
7 changed files with 35 additions and 63 deletions

View file

@ -531,7 +531,7 @@ struct efi_device_path *eficonfig_create_device_path(struct efi_device_path *dp_
dp = efi_dp_shorten(dp_volume);
if (!dp)
dp = dp_volume;
dp = efi_dp_append(dp, &fp->dp);
dp = efi_dp_concat(dp, &fp->dp, false);
free(buf);
return dp;
@ -1484,7 +1484,8 @@ static efi_status_t eficonfig_edit_boot_option(u16 *varname, struct eficonfig_bo
ret = EFI_OUT_OF_RESOURCES;
goto out;
}
initrd_dp = efi_dp_append((const struct efi_device_path *)&id_dp, dp);
initrd_dp = efi_dp_concat((const struct efi_device_path *)&id_dp,
dp, false);
efi_free_pool(dp);
}
@ -1495,7 +1496,7 @@ static efi_status_t eficonfig_edit_boot_option(u16 *varname, struct eficonfig_bo
}
final_dp_size = efi_dp_size(dp) + sizeof(END);
if (initrd_dp) {
final_dp = efi_dp_concat(dp, initrd_dp);
final_dp = efi_dp_concat(dp, initrd_dp, true);
final_dp_size += efi_dp_size(initrd_dp) + sizeof(END);
} else {
final_dp = efi_dp_dup(dp);

View file

@ -699,8 +699,8 @@ struct efi_device_path *create_initrd_dp(const char *dev, const char *part,
if (!short_fp)
short_fp = tmp_fp;
initrd_dp = efi_dp_append((const struct efi_device_path *)&id_dp,
short_fp);
initrd_dp = efi_dp_concat((const struct efi_device_path *)&id_dp,
short_fp, false);
out:
efi_free_pool(tmp_dp);
@ -916,7 +916,7 @@ static int do_efi_boot_add(struct cmd_tbl *cmdtp, int flag,
goto out;
}
final_fp = efi_dp_concat(file_path, initrd_dp);
final_fp = efi_dp_concat(file_path, initrd_dp, true);
if (!final_fp) {
printf("Cannot create final device path\n");
r = CMD_RET_FAILURE;

View file

@ -819,8 +819,6 @@ efi_uintn_t efi_dp_instance_size(const struct efi_device_path *dp);
/* size of multi-instance device path excluding end node */
efi_uintn_t efi_dp_size(const struct efi_device_path *dp);
struct efi_device_path *efi_dp_dup(const struct efi_device_path *dp);
struct efi_device_path *efi_dp_append(const struct efi_device_path *dp1,
const struct efi_device_path *dp2);
struct efi_device_path *efi_dp_append_node(const struct efi_device_path *dp,
const struct efi_device_path *node);
/* Create a device path node of given type, sub-type, length */
@ -937,7 +935,8 @@ struct efi_load_option {
struct efi_device_path *efi_dp_from_lo(struct efi_load_option *lo,
const efi_guid_t *guid);
struct efi_device_path *efi_dp_concat(const struct efi_device_path *dp1,
const struct efi_device_path *dp2);
const struct efi_device_path *dp2,
bool split_end_node);
struct efi_device_path *search_gpt_dp_node(struct efi_device_path *device_path);
efi_status_t efi_deserialize_load_option(struct efi_load_option *lo, u8 *data,
efi_uintn_t *size);

View file

@ -143,7 +143,7 @@ static efi_status_t try_load_from_file_path(efi_handle_t *fs_handles,
if (!dp)
continue;
dp = efi_dp_append(dp, fp);
dp = efi_dp_concat(dp, fp, false);
if (!dp)
continue;
@ -1579,8 +1579,8 @@ efi_status_t efi_run_image(void *source_buffer, efi_uintn_t source_size)
goto out;
msg_path = file_path;
} else {
file_path = efi_dp_append(bootefi_device_path,
bootefi_image_path);
file_path = efi_dp_concat(bootefi_device_path,
bootefi_image_path, false);
msg_path = bootefi_image_path;
log_debug("Loaded from disk\n");
}

View file

@ -1816,7 +1816,7 @@ efi_status_t efi_setup_loaded_image(struct efi_device_path *device_path,
if (device_path) {
info->device_handle = efi_dp_find_obj(device_path, NULL, NULL);
dp = efi_dp_append(device_path, file_path);
dp = efi_dp_concat(device_path, file_path, false);
if (!dp) {
ret = EFI_OUT_OF_RESOURCES;
goto failure;

View file

@ -271,30 +271,27 @@ struct efi_device_path *efi_dp_dup(const struct efi_device_path *dp)
}
/**
* efi_dp_append_or_concatenate() - Append or concatenate two device paths.
* Concatenated device path will be separated
* by a sub-type 0xff end node
* efi_dp_concat() - Concatenate two device paths and add and terminate them
* with an end node.
*
* @dp1: First device path
* @dp2: Second device path
* @concat: If true the two device paths will be concatenated and separated
* by an end of entrire device path sub-type 0xff end node.
* If true the second device path will be appended to the first and
* terminated by an end node
* @dp1: First device path
* @dp2: Second device path
* @split_end_node: If true the two device paths will be concatenated and
* separated by an end node (DEVICE_PATH_SUB_TYPE_END).
* If false the second device path will be concatenated to the
* first one as-is.
*
* Return:
* concatenated device path or NULL. Caller must free the returned value
*/
static struct
efi_device_path *efi_dp_append_or_concatenate(const struct efi_device_path *dp1,
const struct efi_device_path *dp2,
bool concat)
struct
efi_device_path *efi_dp_concat(const struct efi_device_path *dp1,
const struct efi_device_path *dp2,
bool split_end_node)
{
struct efi_device_path *ret;
size_t end_size = sizeof(END);
size_t end_size;
if (concat)
end_size = 2 * sizeof(END);
if (!dp1 && !dp2) {
/* return an end node */
ret = efi_dp_dup(&END);
@ -306,14 +303,20 @@ efi_device_path *efi_dp_append_or_concatenate(const struct efi_device_path *dp1,
/* both dp1 and dp2 are non-null */
unsigned sz1 = efi_dp_size(dp1);
unsigned sz2 = efi_dp_size(dp2);
void *p = efi_alloc(sz1 + sz2 + end_size);
void *p;
if (split_end_node)
end_size = 2 * sizeof(END);
else
end_size = sizeof(END);
p = efi_alloc(sz1 + sz2 + end_size);
if (!p)
return NULL;
ret = p;
memcpy(p, dp1, sz1);
p += sz1;
if (concat) {
if (split_end_node) {
memcpy(p, &END, sizeof(END));
p += sizeof(END);
}
@ -327,37 +330,6 @@ efi_device_path *efi_dp_append_or_concatenate(const struct efi_device_path *dp1,
return ret;
}
/**
* efi_dp_append() - Append a device to an existing device path.
*
* @dp1: First device path
* @dp2: Second device path
*
* Return:
* concatenated device path or NULL. Caller must free the returned value
*/
struct efi_device_path *efi_dp_append(const struct efi_device_path *dp1,
const struct efi_device_path *dp2)
{
return efi_dp_append_or_concatenate(dp1, dp2, false);
}
/**
* efi_dp_concat() - Concatenate 2 device paths. The final device path will
* contain two device paths separated by and end node (0xff).
*
* @dp1: First device path
* @dp2: Second device path
*
* Return:
* concatenated device path or NULL. Caller must free the returned value
*/
struct efi_device_path *efi_dp_concat(const struct efi_device_path *dp1,
const struct efi_device_path *dp2)
{
return efi_dp_append_or_concatenate(dp1, dp2, true);
}
struct efi_device_path *efi_dp_append_node(const struct efi_device_path *dp,
const struct efi_device_path *node)
{

View file

@ -76,7 +76,7 @@ static struct efi_device_path * EFIAPI append_device_path(
const struct efi_device_path *src2)
{
EFI_ENTRY("%pD, %pD", src1, src2);
return EFI_EXIT(efi_dp_append(src1, src2));
return EFI_EXIT(efi_dp_concat(src1, src2, false));
}
/*