From 21b3ddd39feecd2f4d6c52bcd30f0a4fa14f125a Mon Sep 17 00:00:00 2001 From: Sylvain Chouleur Date: Fri, 15 Jul 2016 21:36:30 +0200 Subject: efi: Don't use spinlocks for efi vars All efivars operations are protected by a spinlock which prevents interruptions and preemption. This is too restricted, we just need a lock preventing concurrency. The idea is to use a semaphore of count 1 and to have two ways of locking, depending on the context: - In interrupt context, we call down_trylock(), if it fails we return an error - In normal context, we call down_interruptible() We don't use a mutex here because the mutex_trylock() function must not be called from interrupt context, whereas the down_trylock() can. Signed-off-by: Sylvain Chouleur Signed-off-by: Ard Biesheuvel Cc: Leif Lindholm Cc: Mark Rutland Cc: Sylvain Chouleur Signed-off-by: Matt Fleming --- include/linux/efi.h | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'include/linux/efi.h') diff --git a/include/linux/efi.h b/include/linux/efi.h index deecb2902715..4d6da7b66c19 100644 --- a/include/linux/efi.h +++ b/include/linux/efi.h @@ -1297,8 +1297,8 @@ struct kobject *efivars_kobject(void); int efivar_init(int (*func)(efi_char16_t *, efi_guid_t, unsigned long, void *), void *data, bool duplicates, struct list_head *head); -void efivar_entry_add(struct efivar_entry *entry, struct list_head *head); -void efivar_entry_remove(struct efivar_entry *entry); +int efivar_entry_add(struct efivar_entry *entry, struct list_head *head); +int efivar_entry_remove(struct efivar_entry *entry); int __efivar_entry_delete(struct efivar_entry *entry); int efivar_entry_delete(struct efivar_entry *entry); @@ -1315,7 +1315,7 @@ int efivar_entry_set_get_size(struct efivar_entry *entry, u32 attributes, int efivar_entry_set_safe(efi_char16_t *name, efi_guid_t vendor, u32 attributes, bool block, unsigned long size, void *data); -void efivar_entry_iter_begin(void); +int efivar_entry_iter_begin(void); void efivar_entry_iter_end(void); int __efivar_entry_iter(int (*func)(struct efivar_entry *, void *), -- cgit v1.2.3