FROMLIST: misc: fastrpc: Allow fastrpc_buf_free() to accept NULL

Make fastrpc_buf_free() a no-op when passed a NULL pointer, allowing
callers to avoid open-coded NULL checks.

Link: https://lore.kernel.org/all/20260409062617.1182-5-jianping.li@oss.qualcomm.com/
Co-developed-by: Ekansh Gupta <ekansh.gupta@oss.qualcomm.com>
Signed-off-by: Ekansh Gupta <ekansh.gupta@oss.qualcomm.com>
Signed-off-by: Jianping Li <jianping.li@oss.qualcomm.com>

Author: ekanshibu

drivers/misc/fastrpc.c

@@ -436,6 +436,9 @@ static int fastrpc_map_lookup(struct fastrpc_user *fl, int fd,
 
 static void fastrpc_buf_free(struct fastrpc_buf *buf)
 {
+	if (!buf)
+		return;
+
 	dma_free_coherent(buf->dev, buf->size, buf->virt,
 			  fastrpc_ipa_to_dma_addr(buf->fl->cctx, buf->dma_addr));
 	kfree(buf);
@@ -553,8 +556,7 @@ static void fastrpc_context_free(struct kref *ref)
 	for (i = 0; i < ctx->nbufs; i++)
 		fastrpc_map_put(ctx->maps[i]);
 
-	if (ctx->buf)
-		fastrpc_buf_free(ctx->buf);
+	fastrpc_buf_free(ctx->buf);
 
 	spin_lock_irqsave(&cctx->lock, flags);
 	idr_remove(&cctx->ctx_idr, FIELD_GET(FASTRPC_CTXID_MASK, ctx->ctxid));
@@ -1687,8 +1689,7 @@ static int fastrpc_device_release(struct inode *inode, struct file *file)
 	list_del(&fl->user);
 	spin_unlock_irqrestore(&cctx->lock, flags);
 
-	if (fl->init_mem)
-		fastrpc_buf_free(fl->init_mem);
+	fastrpc_buf_free(fl->init_mem);
 
 	list_for_each_entry_safe(ctx, n, &fl->pending, node) {
 		list_del(&ctx->node);