agp: Remove the BKL from agp_open
- Remove the BKL from agp_open
- Perform a few clean-ups.
Analysis:
---------
int minor is local to the function.
The following are protected by agp_fe.agp_mutex
struct agp_file_private *priv;
struct agp_client *client;
Call-outs:
kzalloc should be safe to call under the mutex_lock
agp_find_client_by_pid:
- agp_mmap calls that under agp_fe.agp_mutex which we hold in agp_open
- agpioc_reserve_wrap calls it without any locking what-so-ever.
- Is that an error? Or is that okay because it has pid that is
a unique handle?
agp_insert_file_private:
- This function only manipulates struct agp_file_private, once again
while agp_fe.agp_mutex is held
Signed-off-by: John Kacur <jkacur@redhat.com>
Acked-by: David Airlie <airlied@linux.ie>
LKML-Reference: <alpine.LFD.2.00.0910112216060.12574@localhost.localdomain>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/drivers/char/agp/frontend.c b/drivers/char/agp/frontend.c
index a96f319..43412c0 100644
--- a/drivers/char/agp/frontend.c
+++ b/drivers/char/agp/frontend.c
@@ -676,25 +676,25 @@
int minor = iminor(inode);
struct agp_file_private *priv;
struct agp_client *client;
- int rc = -ENXIO;
-
- lock_kernel();
- mutex_lock(&(agp_fe.agp_mutex));
if (minor != AGPGART_MINOR)
- goto err_out;
+ return -ENXIO;
+
+ mutex_lock(&(agp_fe.agp_mutex));
priv = kzalloc(sizeof(struct agp_file_private), GFP_KERNEL);
- if (priv == NULL)
- goto err_out_nomem;
+ if (priv == NULL) {
+ mutex_unlock(&(agp_fe.agp_mutex));
+ return -ENOMEM;
+ }
set_bit(AGP_FF_ALLOW_CLIENT, &priv->access_flags);
priv->my_pid = current->pid;
- if (capable(CAP_SYS_RAWIO)) {
+ if (capable(CAP_SYS_RAWIO))
/* Root priv, can be controller */
set_bit(AGP_FF_ALLOW_CONTROLLER, &priv->access_flags);
- }
+
client = agp_find_client_by_pid(current->pid);
if (client != NULL) {
@@ -704,16 +704,10 @@
file->private_data = (void *) priv;
agp_insert_file_private(priv);
DBG("private=%p, client=%p", priv, client);
- mutex_unlock(&(agp_fe.agp_mutex));
- unlock_kernel();
- return 0;
-err_out_nomem:
- rc = -ENOMEM;
-err_out:
mutex_unlock(&(agp_fe.agp_mutex));
- unlock_kernel();
- return rc;
+
+ return 0;
}