qemu/system-physmem-Propagate-AddressSpace-to-MapClient-h.patch

From 3e13a72b4b99a74767267b2e9a9e4f6cafae7e66 Mon Sep 17 00:00:00 2001
From: Mattias Nissler <mnissler@rivosinc.com>
Date: Thu, 7 Sep 2023 06:04:23 -0700
Subject: [PATCH 1/5] system/physmem: Propagate AddressSpace to MapClient
 helpers
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

cherry-pick from 5c62719710bab66a98f68ebdba333e2240ed6668

Propagate AddressSpace handler to following helpers:
- register_map_client()
- unregister_map_client()
- notify_map_clients[_locked]()

Rename them using 'address_space_' prefix instead of 'cpu_'.

The AddressSpace argument will be used in the next commit.

Reviewed-by: Peter Xu <peterx@redhat.com>
Tested-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Mattias Nissler <mnissler@rivosinc.com>
Message-ID: <20240507094210.300566-2-mnissler@rivosinc.com>
[PMD: Split patch, part 1/2]
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
---
 dma-helpers.c             |  4 ++--
 exec.c                    | 24 ++++++++++++------------
 include/exec/cpu-common.h |  2 --
 include/exec/memory.h     | 26 ++++++++++++++++++++++++--
 4 files changed, 38 insertions(+), 18 deletions(-)

diff --git a/dma-helpers.c b/dma-helpers.c
index d3871dc61e..397b437734 100644
--- a/dma-helpers.c
+++ b/dma-helpers.c
@@ -155,7 +155,7 @@ static void dma_blk_cb(void *opaque, int ret)
     if (dbs->iov.size == 0) {
         trace_dma_map_wait(dbs);
         dbs->bh = aio_bh_new(dbs->ctx, reschedule_dma, dbs);
-        cpu_register_map_client(dbs->bh);
+        address_space_register_map_client(dbs->sg->as, dbs->bh);
         return;
     }
 
@@ -185,7 +185,7 @@ static void dma_aio_cancel(BlockAIOCB *acb)
     }
 
     if (dbs->bh) {
-        cpu_unregister_map_client(dbs->bh);
+        address_space_unregister_map_client(dbs->sg->as, dbs->bh);
         qemu_bh_delete(dbs->bh);
         dbs->bh = NULL;
     }
diff --git a/exec.c b/exec.c
index 0a6ac67c84..bb549f63ce 100644
--- a/exec.c
+++ b/exec.c
@@ -3629,24 +3629,24 @@ QemuMutex map_client_list_lock;
 static QLIST_HEAD(, MapClient) map_client_list
     = QLIST_HEAD_INITIALIZER(map_client_list);
 
-static void cpu_unregister_map_client_do(MapClient *client)
+static void address_space_unregister_map_client_do(MapClient *client)
 {
     QLIST_REMOVE(client, link);
     g_free(client);
 }
 
-static void cpu_notify_map_clients_locked(void)
+static void address_space_notify_map_clients_locked(AddressSpace *as)
 {
     MapClient *client;
 
     while (!QLIST_EMPTY(&map_client_list)) {
         client = QLIST_FIRST(&map_client_list);
         qemu_bh_schedule(client->bh);
-        cpu_unregister_map_client_do(client);
+        address_space_unregister_map_client_do(client);
     }
 }
 
-void cpu_register_map_client(QEMUBH *bh)
+void address_space_register_map_client(AddressSpace *as, QEMUBH *bh)
 {
     MapClient *client = g_malloc(sizeof(*client));
 
@@ -3654,7 +3654,7 @@ void cpu_register_map_client(QEMUBH *bh)
     client->bh = bh;
     QLIST_INSERT_HEAD(&map_client_list, client, link);
     if (!atomic_read(&bounce.in_use)) {
-        cpu_notify_map_clients_locked();
+        address_space_notify_map_clients_locked(as);
     }
     qemu_mutex_unlock(&map_client_list_lock);
 }
@@ -3675,24 +3675,24 @@ void cpu_exec_init_all(void)
     qemu_mutex_init(&map_client_list_lock);
 }
 
-void cpu_unregister_map_client(QEMUBH *bh)
+void address_space_unregister_map_client(AddressSpace *as, QEMUBH *bh)
 {
     MapClient *client;
 
     qemu_mutex_lock(&map_client_list_lock);
     QLIST_FOREACH(client, &map_client_list, link) {
         if (client->bh == bh) {
-            cpu_unregister_map_client_do(client);
+            address_space_unregister_map_client_do(client);
             break;
         }
     }
     qemu_mutex_unlock(&map_client_list_lock);
 }
 
-static void cpu_notify_map_clients(void)
+static void address_space_notify_map_clients(AddressSpace *as)
 {
     qemu_mutex_lock(&map_client_list_lock);
-    cpu_notify_map_clients_locked();
+    address_space_notify_map_clients_locked(as);
     qemu_mutex_unlock(&map_client_list_lock);
 }
 
@@ -3763,8 +3763,8 @@ flatview_extend_translation(FlatView *fv, hwaddr addr,
  * May map a subset of the requested range, given by and returned in *plen.
  * May return NULL if resources needed to perform the mapping are exhausted.
  * Use only for reads OR writes - not for read-modify-write operations.
- * Use cpu_register_map_client() to know when retrying the map operation is
- * likely to succeed.
+ * Use address_space_register_map_client() to know when retrying the map
+ * operation is likely to succeed.
  */
 void *address_space_map(AddressSpace *as,
                         hwaddr addr,
@@ -3851,7 +3851,7 @@ void address_space_unmap(AddressSpace *as, void *buffer, hwaddr len,
     bounce.buffer = NULL;
     memory_region_unref(bounce.mr);
     atomic_mb_set(&bounce.in_use, false);
-    cpu_notify_map_clients();
+    address_space_notify_map_clients(as);
 }
 
 void *cpu_physical_memory_map(hwaddr addr,
diff --git a/include/exec/cpu-common.h b/include/exec/cpu-common.h
index f7dbe75fbc..6070fa83ff 100644
--- a/include/exec/cpu-common.h
+++ b/include/exec/cpu-common.h
@@ -86,8 +86,6 @@ void *cpu_physical_memory_map(hwaddr addr,
                               int is_write);
 void cpu_physical_memory_unmap(void *buffer, hwaddr len,
                                int is_write, hwaddr access_len);
-void cpu_register_map_client(QEMUBH *bh);
-void cpu_unregister_map_client(QEMUBH *bh);
 
 bool cpu_physical_memory_is_io(hwaddr phys_addr);
 
diff --git a/include/exec/memory.h b/include/exec/memory.h
index ad260ebbd6..aa35416d80 100644
--- a/include/exec/memory.h
+++ b/include/exec/memory.h
@@ -2072,8 +2072,8 @@ bool address_space_access_valid(AddressSpace *as, hwaddr addr, hwaddr len,
  * May return %NULL and set *@plen to zero(0), if resources needed to perform
  * the mapping are exhausted.
  * Use only for reads OR writes - not for read-modify-write operations.
- * Use cpu_register_map_client() to know when retrying the map operation is
- * likely to succeed.
+ * Use address_space_register_map_client() to know when retrying the map
+ * operation is likely to succeed.
  *
  * @as: #AddressSpace to be accessed
  * @addr: address within that address space
@@ -2098,6 +2098,28 @@ void *address_space_map(AddressSpace *as, hwaddr addr,
 void address_space_unmap(AddressSpace *as, void *buffer, hwaddr len,
                          int is_write, hwaddr access_len);
 
+/*
+ * address_space_register_map_client: Register a callback to invoke when
+ * resources for address_space_map() are available again.
+ *
+ * address_space_map may fail when there are not enough resources available,
+ * such as when bounce buffer memory would exceed the limit. The callback can
+ * be used to retry the address_space_map operation. Note that the callback
+ * gets automatically removed after firing.
+ *
+ * @as: #AddressSpace to be accessed
+ * @bh: callback to invoke when address_space_map() retry is appropriate
+ */
+void address_space_register_map_client(AddressSpace *as, QEMUBH *bh);
+
+/*
+ * address_space_unregister_map_client: Unregister a callback that has
+ * previously been registered and not fired yet.
+ *
+ * @as: #AddressSpace to be accessed
+ * @bh: callback to unregister
+ */
+void address_space_unregister_map_client(AddressSpace *as, QEMUBH *bh);
 
 /* Internal functions, part of the implementation of address_space_read.  */
 MemTxResult address_space_read_full(AddressSpace *as, hwaddr addr,
-- 
2.45.1.windows.1