diff options
| author | Sylvain Chouleur <sylvain.chouleur@intel.com> | 2016-07-15 21:36:30 +0200 |
|---|---|---|
| committer | Matt Fleming <matt@codeblueprint.co.uk> | 2016-09-09 16:08:42 +0100 |
| commit | 21b3ddd39feecd2f4d6c52bcd30f0a4fa14f125a (patch) | |
| tree | 40773635e6415ce23293c67eda0327dddec90ae7 /fs/efivarfs/inode.c | |
| parent | 217b27d4671a0a3f34147f1b341683d36b7457db (diff) | |
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 'fs/efivarfs/inode.c')
| -rw-r--r-- | fs/efivarfs/inode.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/fs/efivarfs/inode.c b/fs/efivarfs/inode.c index 1d73fc6dba13..cbb50cadcffc 100644 --- a/fs/efivarfs/inode.c +++ b/fs/efivarfs/inode.c @@ -105,7 +105,10 @@ static int efivarfs_create(struct inode *dir, struct dentry *dentry, inode->i_private = var; - efivar_entry_add(var, &efivarfs_list); + err = efivar_entry_add(var, &efivarfs_list); + if (err) + goto out; + d_instantiate(dentry, inode); dget(dentry); out: |