[PATCH 1/3] fastrpc: always use fl->lock and remove fl->mutex

[Jonathan Marek]

Fix the broken behavior of having a separate mutex for locking at this
place, and use the same spinlock that is used to add/remove from the list.

Signed-off-by: Jonathan Marek <jonat...@marek.ca>
---
 drivers/misc/fastrpc.c | 11 +++--------
 1 file changed, 3 insertions(+), 8 deletions(-)

diff --git a/drivers/misc/fastrpc.c b/drivers/misc/fastrpc.c
index f12e909034ac..4fabea0c1551 100644
--- a/drivers/misc/fastrpc.c
+++ b/drivers/misc/fastrpc.c
@@ -230,8 +230,6 @@ struct fastrpc_user {
        int pd;
        /* Lock for lists */
        spinlock_t lock;
-       /* lock for allocations */
-       struct mutex mutex;
 };
 
 static void fastrpc_free_map(struct kref *ref)
@@ -267,16 +265,16 @@ static int fastrpc_map_find(struct fastrpc_user *fl, int 
fd,
 {
        struct fastrpc_map *map = NULL;
 
-       mutex_lock(&fl->mutex);
+       spin_lock(&fl->lock);
        list_for_each_entry(map, &fl->maps, node) {
                if (map->fd == fd) {
                        fastrpc_map_get(map);
                        *ppmap = map;
-                       mutex_unlock(&fl->mutex);
+                       spin_unlock(&fl->lock);
                        return 0;
                }
        }
-       mutex_unlock(&fl->mutex);
+       spin_unlock(&fl->lock);
 
        return -ENOENT;
 }
@@ -1200,7 +1198,6 @@ static int fastrpc_device_release(struct inode *inode, 
struct file *file)
        fastrpc_session_free(cctx, fl->sctx);
        fastrpc_channel_ctx_put(cctx);
 
-       mutex_destroy(&fl->mutex);
        kfree(fl);
        file->private_data = NULL;
 
@@ -1222,7 +1219,6 @@ static int fastrpc_device_open(struct inode *inode, 
struct file *filp)
 
        filp->private_data = fl;
        spin_lock_init(&fl->lock);
-       mutex_init(&fl->mutex);
        INIT_LIST_HEAD(&fl->pending);
        INIT_LIST_HEAD(&fl->maps);
        INIT_LIST_HEAD(&fl->mmaps);
@@ -1233,7 +1229,6 @@ static int fastrpc_device_open(struct inode *inode, 
struct file *filp)
        fl->sctx = fastrpc_session_alloc(cctx);
        if (!fl->sctx) {
                dev_err(&cctx->rpdev->dev, "No session available\n");
-               mutex_destroy(&fl->mutex);
                kfree(fl);
 
                return -EBUSY;
-- 
2.26.1