firmware: stratix10-svc: Add mutex in stratix10 memory management

Add mutex lock to stratix10_svc_allocate_memory and
stratix10_svc_free_memory for thread safety. This prevents race
conditions and ensures proper synchronization during memory operations.
This is required for parallel communication with the Stratix10 service
channel.

Fixes: 7ca5ce896524f ("firmware: add Intel Stratix10 service layer driver")
Cc: stable@vger.kernel.org
Signed-off-by: Mahesh Rao <mahesh.rao@altera.com>
Reviewed-by: Matthew Gerlach <matthew.gerlach@altera.com>
Signed-off-by: Dinh Nguyen <dinguyen@kernel.org>

diff --git a/drivers/firmware/stratix10-svc.c b/drivers/firmware/stratix10-svc.c
index 5a32c1054bee1d05809bbe828880ce4f30534c96..9372a17d89b7ceccee5e6efa23303175caddd038 100644 (file)
--- a/drivers/firmware/stratix10-svc.c
+++ b/drivers/firmware/stratix10-svc.c
@@ -1,6 +1,7 @@
 // SPDX-License-Identifier: GPL-2.0
 /*
  * Copyright (C) 2017-2018, Intel Corporation
+ * Copyright (C) 2025, Altera Corporation
  */
 
 #include <linux/completion.h>
@@ -172,6 +173,12 @@ struct stratix10_svc_chan {
 static LIST_HEAD(svc_ctrl);
 static LIST_HEAD(svc_data_mem);
 
+/**
+ * svc_mem_lock protects access to the svc_data_mem list for
+ * concurrent multi-client operations
+ */
+static DEFINE_MUTEX(svc_mem_lock);
+
 /**
  * svc_pa_to_va() - translate physical address to virtual address
  * @addr: to be translated physical address
@@ -184,6 +191,7 @@ static void *svc_pa_to_va(unsigned long addr)
        struct stratix10_svc_data_mem *pmem;
 
        pr_debug("claim back P-addr=0x%016x\n", (unsigned int)addr);
+       guard(mutex)(&svc_mem_lock);
        list_for_each_entry(pmem, &svc_data_mem, node)
                if (pmem->paddr == addr)
                        return pmem->vaddr;
@@ -1002,6 +1010,7 @@ int stratix10_svc_send(struct stratix10_svc_chan *chan, void *msg)
                        p_data->flag = ct->flags;
                }
        } else {
+               guard(mutex)(&svc_mem_lock);
                list_for_each_entry(p_mem, &svc_data_mem, node)
                        if (p_mem->vaddr == p_msg->payload) {
                                p_data->paddr = p_mem->paddr;
@@ -1084,6 +1093,7 @@ void *stratix10_svc_allocate_memory(struct stratix10_svc_chan *chan,
        if (!pmem)
                return ERR_PTR(-ENOMEM);
 
+       guard(mutex)(&svc_mem_lock);
        va = gen_pool_alloc(genpool, s);
        if (!va)
                return ERR_PTR(-ENOMEM);
@@ -1112,6 +1122,7 @@ EXPORT_SYMBOL_GPL(stratix10_svc_allocate_memory);
 void stratix10_svc_free_memory(struct stratix10_svc_chan *chan, void *kaddr)
 {
        struct stratix10_svc_data_mem *pmem;
+       guard(mutex)(&svc_mem_lock);
 
        list_for_each_entry(pmem, &svc_data_mem, node)
                if (pmem->vaddr == kaddr) {