diff options
| -rw-r--r-- | arch/x86/platform/efi/quirks.c | 33 | ||||
| -rw-r--r-- | drivers/firmware/efi/vars.c | 16 | ||||
| -rw-r--r-- | include/linux/efi.h | 12 |
3 files changed, 55 insertions, 6 deletions
diff --git a/arch/x86/platform/efi/quirks.c b/arch/x86/platform/efi/quirks.c index 453504662a33..2326bf51978f 100644 --- a/arch/x86/platform/efi/quirks.c +++ b/arch/x86/platform/efi/quirks.c @@ -57,13 +57,41 @@ void efi_delete_dummy_variable(void) } /* + * In the nonblocking case we do not attempt to perform garbage + * collection if we do not have enough free space. Rather, we do the + * bare minimum check and give up immediately if the available space + * is below EFI_MIN_RESERVE. + * + * This function is intended to be small and simple because it is + * invoked from crash handler paths. + */ +static efi_status_t +query_variable_store_nonblocking(u32 attributes, unsigned long size) +{ + efi_status_t status; + u64 storage_size, remaining_size, max_size; + + status = efi.query_variable_info_nonblocking(attributes, &storage_size, + &remaining_size, + &max_size); + if (status != EFI_SUCCESS) + return status; + + if (remaining_size - size < EFI_MIN_RESERVE) + return EFI_OUT_OF_RESOURCES; + + return EFI_SUCCESS; +} + +/* * Some firmware implementations refuse to boot if there's insufficient space * in the variable store. Ensure that we never use more than a safe limit. * * Return EFI_SUCCESS if it is safe to write 'size' bytes to the variable * store. */ -efi_status_t efi_query_variable_store(u32 attributes, unsigned long size) +efi_status_t efi_query_variable_store(u32 attributes, unsigned long size, + bool nonblocking) { efi_status_t status; u64 storage_size, remaining_size, max_size; @@ -71,6 +99,9 @@ efi_status_t efi_query_variable_store(u32 attributes, unsigned long size) if (!(attributes & EFI_VARIABLE_NON_VOLATILE)) return 0; + if (nonblocking) + return query_variable_store_nonblocking(attributes, size); + status = efi.query_variable_info(attributes, &storage_size, &remaining_size, &max_size); if (status != EFI_SUCCESS) diff --git a/drivers/firmware/efi/vars.c b/drivers/firmware/efi/vars.c index 70a0fb10517f..d2a49626a335 100644 --- a/drivers/firmware/efi/vars.c +++ b/drivers/firmware/efi/vars.c @@ -234,7 +234,18 @@ check_var_size(u32 attributes, unsigned long size) if (!fops->query_variable_store) return EFI_UNSUPPORTED; - return fops->query_variable_store(attributes, size); + return fops->query_variable_store(attributes, size, false); +} + +static efi_status_t +check_var_size_nonblocking(u32 attributes, unsigned long size) +{ + const struct efivar_operations *fops = __efivars->ops; + + if (!fops->query_variable_store) + return EFI_UNSUPPORTED; + + return fops->query_variable_store(attributes, size, true); } static int efi_status_to_err(efi_status_t status) @@ -615,7 +626,8 @@ efivar_entry_set_nonblocking(efi_char16_t *name, efi_guid_t vendor, if (!spin_trylock_irqsave(&__efivars->lock, flags)) return -EBUSY; - status = check_var_size(attributes, size + ucs2_strsize(name, 1024)); + status = check_var_size_nonblocking(attributes, + size + ucs2_strsize(name, 1024)); if (status != EFI_SUCCESS) { spin_unlock_irqrestore(&__efivars->lock, flags); return -ENOSPC; diff --git a/include/linux/efi.h b/include/linux/efi.h index ad1e177ba48e..09f1559e7525 100644 --- a/include/linux/efi.h +++ b/include/linux/efi.h @@ -525,7 +525,9 @@ typedef efi_status_t efi_query_capsule_caps_t(efi_capsule_header_t **capsules, unsigned long count, u64 *max_size, int *reset_type); -typedef efi_status_t efi_query_variable_store_t(u32 attributes, unsigned long size); +typedef efi_status_t efi_query_variable_store_t(u32 attributes, + unsigned long size, + bool nonblocking); void efi_native_runtime_setup(void); @@ -881,13 +883,17 @@ extern void efi_enter_virtual_mode (void); /* switch EFI to virtual mode, if pos #ifdef CONFIG_X86 extern void efi_late_init(void); extern void efi_free_boot_services(void); -extern efi_status_t efi_query_variable_store(u32 attributes, unsigned long size); +extern efi_status_t efi_query_variable_store(u32 attributes, + unsigned long size, + bool nonblocking); extern void efi_find_mirror(void); #else static inline void efi_late_init(void) {} static inline void efi_free_boot_services(void) {} -static inline efi_status_t efi_query_variable_store(u32 attributes, unsigned long size) +static inline efi_status_t efi_query_variable_store(u32 attributes, + unsigned long size, + bool nonblocking) { return EFI_SUCCESS; } |