UEFI volatile variables are managed in efi_var_htab while UEFI non-volatile variables are in efi_nv_var_htab. At every SetVariable API, env_efi_save() will also be called to save data cache (hash table) to persistent storage.
Signed-off-by: AKASHI Takahiro takahiro.akashi@linaro.org --- lib/efi_loader/Kconfig | 10 + lib/efi_loader/efi_variable.c | 342 ++++++++++++++++++++++++++-------- 2 files changed, 275 insertions(+), 77 deletions(-)
diff --git a/lib/efi_loader/Kconfig b/lib/efi_loader/Kconfig index cd5436c576b1..8bf4b1754d06 100644 --- a/lib/efi_loader/Kconfig +++ b/lib/efi_loader/Kconfig @@ -18,6 +18,16 @@ config EFI_LOADER
if EFI_LOADER
+choice + prompt "Select variables storage" + default EFI_VARIABLE_USE_ENV + +config EFI_VARIABLE_USE_ENV + bool "Same device as U-Boot environment" + select ENV_EFI + +endchoice + config EFI_GET_TIME bool "GetTime() runtime service" depends on DM_RTC diff --git a/lib/efi_loader/efi_variable.c b/lib/efi_loader/efi_variable.c index e56053194dae..d9887be938c2 100644 --- a/lib/efi_loader/efi_variable.c +++ b/lib/efi_loader/efi_variable.c @@ -48,6 +48,66 @@ * converted to utf16? */
+/* + * We will maintain two variable database: one for volatile variables, + * the other for non-volatile variables. The former exists only in memory + * and will go away at re-boot. The latter is currently backed up by the same + * device as U-Boot environment and also works as variables cache. + * + * struct hsearch_data efi_var_htab + * struct hsearch_data efi_nv_var_htab + */ + +static char *env_efi_get(const char *name, bool is_non_volatile) +{ + struct hsearch_data *htab; + ENTRY e, *ep; + + /* WATCHDOG_RESET(); */ + + if (is_non_volatile) + htab = &efi_nv_var_htab; + else + htab = &efi_var_htab; + + e.key = name; + e.data = NULL; + hsearch_r(e, FIND, &ep, htab, 0); + + return ep ? ep->data : NULL; +} + +static int env_efi_set(const char *name, const char *value, + bool is_non_volatile) +{ + struct hsearch_data *htab; + ENTRY e, *ep; + int ret; + + if (is_non_volatile) + htab = &efi_nv_var_htab; + else + htab = &efi_var_htab; + + /* delete */ + if (!value || *value == '\0') { + ret = hdelete_r(name, htab, H_PROGRAMMATIC); + return !ret; + } + + /* set */ + e.key = name; + e.data = (char *)value; + hsearch_r(e, ENTER, &ep, htab, H_PROGRAMMATIC); + if (!ep) { + printf("## Error inserting "%s" variable, errno=%d\n", + name, errno); + return 1; + } + + return 0; +} + #define PREFIX_LEN (strlen("efi_xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx_"))
/** @@ -147,24 +207,12 @@ static const char *parse_attr(const char *str, u32 *attrp) return str; }
-/** - * efi_efi_get_variable() - retrieve value of a UEFI variable - * - * This function implements the GetVariable runtime service. - * - * See the Unified Extensible Firmware Interface (UEFI) specification for - * details. - * - * @variable_name: name of the variable - * @vendor: vendor GUID - * @attributes: attributes of the variable - * @data_size: size of the buffer to which the variable value is copied - * @data: buffer to which the variable value is copied - * Return: status code - */ -efi_status_t EFIAPI efi_get_variable(u16 *variable_name, - const efi_guid_t *vendor, u32 *attributes, - efi_uintn_t *data_size, void *data) +static +efi_status_t EFIAPI efi_get_variable_common(u16 *variable_name, + const efi_guid_t *vendor, + u32 *attributes, + efi_uintn_t *data_size, void *data, + bool is_non_volatile) { char *native_name; efi_status_t ret; @@ -172,22 +220,19 @@ efi_status_t EFIAPI efi_get_variable(u16 *variable_name, const char *val, *s; u32 attr;
- EFI_ENTRY(""%ls" %pUl %p %p %p", variable_name, vendor, attributes, - data_size, data); - if (!variable_name || !vendor || !data_size) return EFI_EXIT(EFI_INVALID_PARAMETER);
ret = efi_to_native(&native_name, variable_name, vendor); if (ret) - return EFI_EXIT(ret); + return ret;
EFI_PRINT("get '%s'\n", native_name);
- val = env_get(native_name); + val = env_efi_get(native_name, is_non_volatile); free(native_name); if (!val) - return EFI_EXIT(EFI_NOT_FOUND); + return EFI_NOT_FOUND;
val = parse_attr(val, &attr);
@@ -198,7 +243,7 @@ efi_status_t EFIAPI efi_get_variable(u16 *variable_name,
/* number of hexadecimal digits must be even */ if (len & 1) - return EFI_EXIT(EFI_DEVICE_ERROR); + return EFI_DEVICE_ERROR;
/* two characters per byte: */ len /= 2; @@ -210,10 +255,10 @@ efi_status_t EFIAPI efi_get_variable(u16 *variable_name, }
if (!data) - return EFI_EXIT(EFI_INVALID_PARAMETER); + return EFI_INVALID_PARAMETER;
if (hex2bin(data, s, len)) - return EFI_EXIT(EFI_DEVICE_ERROR); + return EFI_DEVICE_ERROR;
EFI_PRINT("got value: "%s"\n", s); } else if ((s = prefix(val, "(utf8)"))) { @@ -227,7 +272,7 @@ efi_status_t EFIAPI efi_get_variable(u16 *variable_name, }
if (!data) - return EFI_EXIT(EFI_INVALID_PARAMETER); + return EFI_INVALID_PARAMETER;
memcpy(data, s, len); ((char *)data)[len] = '\0'; @@ -235,13 +280,67 @@ efi_status_t EFIAPI efi_get_variable(u16 *variable_name, EFI_PRINT("got value: "%s"\n", (char *)data); } else { EFI_PRINT("invalid value: '%s'\n", val); - return EFI_EXIT(EFI_DEVICE_ERROR); + return EFI_DEVICE_ERROR; }
out: if (attributes) *attributes = attr & EFI_VARIABLE_MASK;
+ return ret; +} + +static +efi_status_t EFIAPI efi_get_volatile_variable(u16 *variable_name, + const efi_guid_t *vendor, + u32 *attributes, + efi_uintn_t *data_size, + void *data) +{ + return efi_get_variable_common(variable_name, vendor, attributes, + data_size, data, false); +} + +efi_status_t EFIAPI efi_get_nonvolatile_variable(u16 *variable_name, + const efi_guid_t *vendor, + u32 *attributes, + efi_uintn_t *data_size, + void *data) +{ + return efi_get_variable_common(variable_name, vendor, attributes, + data_size, data, true); +} + +/** + * efi_efi_get_variable() - retrieve value of a UEFI variable + * + * This function implements the GetVariable runtime service. + * + * See the Unified Extensible Firmware Interface (UEFI) specification for + * details. + * + * @variable_name: name of the variable + * @vendor: vendor GUID + * @attributes: attributes of the variable + * @data_size: size of the buffer to which the variable value is copied + * @data: buffer to which the variable value is copied + * Return: status code + */ +efi_status_t EFIAPI efi_get_variable(u16 *variable_name, + const efi_guid_t *vendor, u32 *attributes, + efi_uintn_t *data_size, void *data) +{ + efi_status_t ret; + + EFI_ENTRY(""%ls" %pUl %p %p %p", variable_name, vendor, attributes, + data_size, data); + + ret = efi_get_volatile_variable(variable_name, vendor, attributes, + data_size, data); + if (ret == EFI_NOT_FOUND) + ret = efi_get_nonvolatile_variable(variable_name, vendor, + attributes, data_size, data); + return EFI_EXIT(ret); }
@@ -331,7 +430,7 @@ efi_status_t EFIAPI efi_get_next_variable_name(efi_uintn_t *variable_name_size, u16 *variable_name, const efi_guid_t *vendor) { - char *native_name, *variable; + char *native_name, *variable, *tmp_list, *merged_list; ssize_t name_len, list_len; char regex[256]; char * const regexlist[] = {regex}; @@ -387,10 +486,39 @@ efi_status_t EFIAPI efi_get_next_variable_name(efi_uintn_t *variable_name_size, efi_cur_variable = NULL;
snprintf(regex, 256, "efi_.*-.*-.*-.*-.*_.*"); - list_len = hexport_r(&env_htab, '\n', + list_len = hexport_r(&efi_var_htab, '\n', H_MATCH_REGEX | H_MATCH_KEY, &efi_variables_list, 0, 1, regexlist); - /* 1 indicates that no match was found */ + /* + * Note: '1' indicates that nothing is matched + */ + if (list_len <= 1) { + free(efi_variables_list); + efi_variables_list = NULL; + list_len = hexport_r(&efi_nv_var_htab, '\n', + H_MATCH_REGEX | H_MATCH_KEY, + &efi_variables_list, 0, 1, + regexlist); + } else { + tmp_list = NULL; + list_len = hexport_r(&efi_nv_var_htab, '\n', + H_MATCH_REGEX | H_MATCH_KEY, + &tmp_list, 0, 1, + regexlist); + if (list_len <= 1) { + list_len = 2; /* don't care actual number */ + } else { + /* merge two variables lists */ + merged_list = malloc(strlen(efi_variables_list) + + strlen(tmp_list) + 1); + strcpy(merged_list, efi_variables_list); + strcat(merged_list, tmp_list); + free(efi_variables_list); + free(tmp_list); + efi_variables_list = merged_list; + } + } + if (list_len <= 1) return EFI_EXIT(EFI_NOT_FOUND);
@@ -403,77 +531,71 @@ efi_status_t EFIAPI efi_get_next_variable_name(efi_uintn_t *variable_name_size, return EFI_EXIT(ret); }
-/** - * efi_efi_set_variable() - set value of a UEFI variable - * - * This function implements the SetVariable runtime service. - * - * See the Unified Extensible Firmware Interface (UEFI) specification for - * details. - * - * @variable_name: name of the variable - * @vendor: vendor GUID - * @attributes: attributes of the variable - * @data_size: size of the buffer with the variable value - * @data: buffer with the variable value - * Return: status code - */ -efi_status_t EFIAPI efi_set_variable(u16 *variable_name, - const efi_guid_t *vendor, u32 attributes, - efi_uintn_t data_size, const void *data) +static +efi_status_t EFIAPI efi_set_variable_common(u16 *variable_name, + const efi_guid_t *vendor, + u32 attributes, + efi_uintn_t data_size, + const void *data, + bool is_non_volatile) { char *native_name = NULL, *val = NULL, *s; - efi_status_t ret = EFI_SUCCESS; + efi_uintn_t size; u32 attr; - - EFI_ENTRY(""%ls" %pUl %x %zu %p", variable_name, vendor, attributes, - data_size, data); + efi_status_t ret = EFI_SUCCESS;
/* TODO: implement APPEND_WRITE */ if (!variable_name || !vendor || (attributes & EFI_VARIABLE_APPEND_WRITE)) { ret = EFI_INVALID_PARAMETER; - goto out; + goto err; }
ret = efi_to_native(&native_name, variable_name, vendor); if (ret) - goto out; + goto err;
#define ACCESS_ATTR (EFI_VARIABLE_RUNTIME_ACCESS | EFI_VARIABLE_BOOTSERVICE_ACCESS)
- if ((data_size == 0) || !(attributes & ACCESS_ATTR)) { - /* delete the variable: */ - env_set(native_name, NULL); - ret = EFI_SUCCESS; - goto out; + /* check if a variable exists */ + size = 0; + ret = EFI_CALL(efi_get_variable(variable_name, vendor, &attr, + &size, NULL)); + if (ret == EFI_BUFFER_TOO_SMALL) { + if ((is_non_volatile && !(attr & EFI_VARIABLE_NON_VOLATILE)) || + (!is_non_volatile && (attr & EFI_VARIABLE_NON_VOLATILE))) { + ret = EFI_INVALID_PARAMETER; + goto err; + } }
- val = env_get(native_name); - if (val) { - parse_attr(val, &attr); - - /* We should not free val */ - val = NULL; - if (attr & READ_ONLY) { - ret = EFI_WRITE_PROTECTED; + /* delete a variable */ + if (data_size == 0 || !(attributes & ACCESS_ATTR)) { + if (size) { + if (attr & READ_ONLY) { + ret = EFI_WRITE_PROTECTED; + goto err; + } goto out; } + ret = EFI_SUCCESS; + goto err; /* not error, but nothing to do */ + }
+ /* create/modify a variable */ + if (size && attr != attributes) { /* * attributes won't be changed * TODO: take care of APPEND_WRITE once supported */ - if (attr != attributes) { - ret = EFI_INVALID_PARAMETER; - goto out; - } + ret = EFI_INVALID_PARAMETER; + goto err; }
val = malloc(2 * data_size + strlen("{ro,run,boot,nv}(blob)") + 1); if (!val) { ret = EFI_OUT_OF_RESOURCES; - goto out; + goto err; }
s = val; @@ -487,7 +609,7 @@ efi_status_t EFIAPI efi_set_variable(u16 *variable_name, EFI_VARIABLE_RUNTIME_ACCESS); s += sprintf(s, "{"); while (attributes) { - u32 attr = 1 << (ffs(attributes) - 1); + attr = 1 << (ffs(attributes) - 1);
if (attr == EFI_VARIABLE_NON_VOLATILE) s += sprintf(s, "nv"); @@ -509,12 +631,78 @@ efi_status_t EFIAPI efi_set_variable(u16 *variable_name,
EFI_PRINT("setting: %s=%s\n", native_name, val);
- if (env_set(native_name, val)) +out: + ret = EFI_SUCCESS; + if (env_efi_set(native_name, val, is_non_volatile)) ret = EFI_DEVICE_ERROR;
-out: +err: free(native_name); free(val);
+ return ret; +} + +static +efi_status_t EFIAPI efi_set_volatile_variable(u16 *variable_name, + const efi_guid_t *vendor, + u32 attributes, + efi_uintn_t data_size, + const void *data) +{ + return efi_set_variable_common(variable_name, vendor, attributes, + data_size, data, false); +} + +efi_status_t EFIAPI efi_set_nonvolatile_variable(u16 *variable_name, + const efi_guid_t *vendor, + u32 attributes, + efi_uintn_t data_size, + const void *data) +{ + efi_status_t ret; + + ret = efi_set_variable_common(variable_name, vendor, attributes, + data_size, data, true); + if (ret == EFI_SUCCESS) + /* FIXME: what if save failed? */ + if (env_efi_save()) + ret = EFI_DEVICE_ERROR; + + return ret; +} + +/** + * efi_efi_set_variable() - set value of a UEFI variable + * + * This function implements the SetVariable runtime service. + * + * See the Unified Extensible Firmware Interface (UEFI) specification for + * details. + * + * @variable_name: name of the variable + * @vendor: vendor GUID + * @attributes: attributes of the variable + * @data_size: size of the buffer with the variable value + * @data: buffer with the variable value + * Return: status code + */ +efi_status_t EFIAPI efi_set_variable(u16 *variable_name, + const efi_guid_t *vendor, u32 attributes, + efi_uintn_t data_size, const void *data) +{ + efi_status_t ret; + + EFI_ENTRY(""%ls" %pUl %x %zu %p", variable_name, vendor, attributes, + data_size, data); + + if (attributes & EFI_VARIABLE_NON_VOLATILE) + ret = efi_set_nonvolatile_variable(variable_name, vendor, + attributes, + data_size, data); + else + ret = efi_set_volatile_variable(variable_name, vendor, + attributes, data_size, data); + return EFI_EXIT(ret); }