MIPS: VPE: Get rid of BKL.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

1 files changed, 46 insertions, 31 deletions

diff --git a/arch/mips/kernel/vpe.c b/arch/mips/kernel/vpe.c
index eb6c4c5b7fbe..03092ab2a296 100644
--- a/arch/mips/kernel/vpe.c
+++ b/arch/mips/kernel/vpe.c
@@ -144,14 +144,15 @@ struct tc {
 };
 
 struct {
-        /* Virtual processing elements */
-        struct list_head vpe_list;
-
-        /* Thread contexts */
-        struct list_head tc_list;
+        spinlock_t vpe_list_lock;
+        struct list_head vpe_list;      /* Virtual processing elements */
+        spinlock_t tc_list_lock;
+        struct list_head tc_list;       /* Thread contexts */
 } vpecontrol = {
-        .vpe_list = LIST_HEAD_INIT(vpecontrol.vpe_list),
-        .tc_list = LIST_HEAD_INIT(vpecontrol.tc_list)
+        .vpe_list_lock  = SPIN_LOCK_UNLOCKED,
+        .vpe_list       = LIST_HEAD_INIT(vpecontrol.vpe_list),
+        .tc_list_lock   = SPIN_LOCK_UNLOCKED,
+        .tc_list        = LIST_HEAD_INIT(vpecontrol.tc_list)
 };
 
 static void release_progmem(void *ptr);
@@ -159,28 +160,38 @@ static void release_progmem(void *ptr);
 /* get the vpe associated with this minor */
 static struct vpe *get_vpe(int minor)
 {
-        struct vpe *v;
+        struct vpe *res, *v;
 
         if (!cpu_has_mipsmt)
                 return NULL;
 
+        res = NULL;
+        spin_lock(&vpecontrol.vpe_list_lock);
         list_for_each_entry(v, &vpecontrol.vpe_list, list) {
-                if (v->minor == minor)
-                        return v;
+                if (v->minor == minor) {
+                        res = v;
+                        break;
+                }
         }
+        spin_unlock(&vpecontrol.vpe_list_lock);
 
-        return NULL;
+        return res;
 }
 
 /* get the vpe associated with this minor */
 static struct tc *get_tc(int index)
 {
-        struct tc *t;
+        struct tc *res, *t;
 
+        res = NULL;
+        spin_lock(&vpecontrol.tc_list_lock);
         list_for_each_entry(t, &vpecontrol.tc_list, list) {
-                if (t->index == index)
-                        return t;
+                if (t->index == index) {
+                        res = t;
+                        break;
+                }
         }
+        spin_unlock(&vpecontrol.tc_list_lock);
 
         return NULL;
 }
@@ -190,15 +201,17 @@ static struct vpe *alloc_vpe(int minor)
 {
         struct vpe *v;
 
-        if ((v = kzalloc(sizeof(struct vpe), GFP_KERNEL)) == NULL) {
+        if ((v = kzalloc(sizeof(struct vpe), GFP_KERNEL)) == NULL)
                 return NULL;
-        }
 
         INIT_LIST_HEAD(&v->tc);
+        spin_lock(&vpecontrol.vpe_list_lock);
         list_add_tail(&v->list, &vpecontrol.vpe_list);
+        spin_unlock(&vpecontrol.vpe_list_lock);
 
         INIT_LIST_HEAD(&v->notify);
         v->minor = minor;
+
         return v;
 }
 
@@ -212,7 +225,10 @@ static struct tc *alloc_tc(int index)
 
         INIT_LIST_HEAD(&tc->tc);
         tc->index = index;
+
+        spin_lock(&vpecontrol.tc_list_lock);
         list_add_tail(&tc->list, &vpecontrol.tc_list);
+        spin_unlock(&vpecontrol.tc_list_lock);
 
 out:
         return tc;
@@ -227,7 +243,7 @@ static void release_vpe(struct vpe *v)
         kfree(v);
 }
 
-static void dump_mtregs(void)
+static void __maybe_unused dump_mtregs(void)
 {
         unsigned long val;
 
@@ -1048,20 +1064,19 @@ static int vpe_open(struct inode *inode, struct file *filp)
         enum vpe_state state;
         struct vpe_notifications *not;
         struct vpe *v;
-        int ret, err = 0;
+        int ret;
 
-        lock_kernel();
         if (minor != iminor(inode)) {
                 /* assume only 1 device at the moment. */
-                printk(KERN_WARNING "VPE loader: only vpe1 is supported\n");
-                err = -ENODEV;
-                goto out;
+                pr_warning("VPE loader: only vpe1 is supported\n");
+
+                return -ENODEV;
         }
 
         if ((v = get_vpe(tclimit)) == NULL) {
-                printk(KERN_WARNING "VPE loader: unable to get vpe\n");
-                err = -ENODEV;
-                goto out;
+                pr_warning("VPE loader: unable to get vpe\n");
+
+                return -ENODEV;
         }
 
         state = xchg(&v->state, VPE_STATE_INUSE);
@@ -1101,8 +1116,8 @@ static int vpe_open(struct inode *inode, struct file *filp)
         v->shared_ptr = NULL;
         v->__start = 0;
 
-out:
         unlock_kernel();
+
         return 0;
 }
 
@@ -1594,14 +1609,14 @@ static void __exit vpe_module_exit(void)
 {
         struct vpe *v, *n;
 
+        device_del(&vpe_device);
+        unregister_chrdev(major, module_name);
+
+        /* No locking needed here */
         list_for_each_entry_safe(v, n, &vpecontrol.vpe_list, list) {
-                if (v->state != VPE_STATE_UNUSED) {
+                if (v->state != VPE_STATE_UNUSED)
                         release_vpe(v);
-                }
         }
-
-        device_del(&vpe_device);
-        unregister_chrdev(major, module_name);
 }
 
 module_init(vpe_module_init);