Revert "FROMLIST: misc: fastrpc: Add reference counting for fastrpc_user structure"

This reverts commit 94b182f.

This change corresponds to the initial (v1) version shared with the
upstream community.

Revert it to apply the complete v4 revision, which includes additional
fixes and updates not present in the earlier version. v4 version
contains this changes as well.

Signed-off-by: Anandu Krishnan E <anandu.e@oss.qualcomm.com>

Author: Anandu Krishnan E

drivers/misc/fastrpc.c

@@ -332,8 +332,6 @@ struct fastrpc_user {
 	spinlock_t lock;
 	/* lock for allocations */
 	struct mutex mutex;
-	/* Reference count */
-	struct kref refcount;
 };
 
 /* Extract SMMU PA from consolidated IOVA */
@@ -551,36 +549,15 @@ static void fastrpc_channel_ctx_put(struct fastrpc_channel_ctx *cctx)
 	kref_put(&cctx->refcount, fastrpc_channel_ctx_free);
 }
 
-static void fastrpc_user_free(struct kref *ref)
-{
-	struct fastrpc_user *fl = container_of(ref, struct fastrpc_user, refcount);
-
-	fastrpc_channel_ctx_put(fl->cctx);
-	mutex_destroy(&fl->mutex);
-	kfree(fl);
-}
-
-static void fastrpc_user_get(struct fastrpc_user *fl)
-{
-	kref_get(&fl->refcount);
-}
-
-static void fastrpc_user_put(struct fastrpc_user *fl)
-{
-	kref_put(&fl->refcount, fastrpc_user_free);
-}
-
 static void fastrpc_context_free(struct kref *ref)
 {
 	struct fastrpc_invoke_ctx *ctx;
 	struct fastrpc_channel_ctx *cctx;
-	struct fastrpc_user *fl;
 	unsigned long flags;
 	int i;
 
 	ctx = container_of(ref, struct fastrpc_invoke_ctx, refcount);
 	cctx = ctx->cctx;
-	fl = ctx->fl;
 
 	for (i = 0; i < ctx->nbufs; i++)
 		fastrpc_map_put(ctx->maps[i]);
@@ -595,8 +572,6 @@ static void fastrpc_context_free(struct kref *ref)
 	kfree(ctx->olaps);
 	kfree(ctx);
 
-	/* Release the reference taken in fastrpc_context_alloc() */
-	fastrpc_user_put(fl);
 	fastrpc_channel_ctx_put(cctx);
 }
 
@@ -704,8 +679,6 @@ static struct fastrpc_invoke_ctx *fastrpc_context_alloc(
 
 	/* Released in fastrpc_context_put() */
 	fastrpc_channel_ctx_get(cctx);
-	/* Take a reference to user, released in fastrpc_context_free() */
-	fastrpc_user_get(user);
 
 	ctx->sc = sc;
 	ctx->retval = -1;
@@ -736,7 +709,6 @@ static struct fastrpc_invoke_ctx *fastrpc_context_alloc(
 	spin_lock(&user->lock);
 	list_del(&ctx->node);
 	spin_unlock(&user->lock);
-	fastrpc_user_put(user);
 	fastrpc_channel_ctx_put(cctx);
 	kfree(ctx->maps);
 	kfree(ctx->olaps);
@@ -1744,9 +1716,11 @@ 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;
-	/* Release the reference taken in fastrpc_device_open */
-	fastrpc_user_put(fl);
 
 	return 0;
 }
@@ -1790,7 +1764,6 @@ static int fastrpc_device_open(struct inode *inode, struct file *filp)
 	spin_lock_irqsave(&cctx->lock, flags);
 	list_add_tail(&fl->user, &cctx->users);
 	spin_unlock_irqrestore(&cctx->lock, flags);
-	kref_init(&fl->refcount);
 
 	return 0;
 }