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| author | Sylvain Chouleur | 2016-07-15 21:36:30 +0200 |
|---|---|---|
| committer | Matt Fleming | 2016-09-09 17:08:42 +0200 |
| commit | 21b3ddd39feecd2f4d6c52bcd30f0a4fa14f125a (patch) | |
| tree | 40773635e6415ce23293c67eda0327dddec90ae7 /include/linux/efi.h | |
| parent | efi: Use a file local lock for efivars (diff) | |
| download | kernel-qcow2-linux-21b3ddd39feecd2f4d6c52bcd30f0a4fa14f125a.tar.gz kernel-qcow2-linux-21b3ddd39feecd2f4d6c52bcd30f0a4fa14f125a.tar.xz kernel-qcow2-linux-21b3ddd39feecd2f4d6c52bcd30f0a4fa14f125a.zip | |
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 <sylvain.chouleur@intel.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Leif Lindholm <leif.lindholm@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Sylvain Chouleur <sylvain.chouleur@gmail.com>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Diffstat (limited to 'include/linux/efi.h')
| -rw-r--r-- | include/linux/efi.h | 6 |
1 files changed, 3 insertions, 3 deletions
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 *), |