[RFC v3 09/24] hw/core/loader: Add a ROM loader notifier

[Mathieu Poirier <mathieu.poirier@linaro.org>]

From: Jean-Philippe Brucker <jean-philippe@linaro.org>

Add a function to register a notifier that is invoked when ROMs get
loaded into guest memory.

It will be used by Arm confidential guest support, in order to register
all blobs loaded into memory with KVM, so that their content is moved
into Realm state and measured into the initial VM state.

Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@linaro.org>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
---
 hw/core/loader.c         | 15 +++++++++++++++
 include/hw/core/loader.h | 17 +++++++++++++++++
 2 files changed, 32 insertions(+)

diff --git a/hw/core/loader.c b/hw/core/loader.c
index 5cbfba0a86d2..388f10e828db 100644
--- a/hw/core/loader.c
+++ b/hw/core/loader.c
@@ -74,6 +74,8 @@
 #endif
 
 static int roms_loaded;
+static NotifierList rom_loader_notifier =
+    NOTIFIER_LIST_INITIALIZER(rom_loader_notifier);
 
 /* return the size or -1 if error */
 int64_t get_image_size(const char *filename, Error **errp)
@@ -1201,6 +1203,11 @@ MemoryRegion *rom_add_blob(const char *name, const void *blob, size_t len,
     return mr;
 }
 
+void rom_add_load_notifier(Notifier *notifier)
+{
+    notifier_list_add(&rom_loader_notifier, notifier);
+}
+
 /* This function is specific for elf program because we don't need to allocate
  * all the rom. We just allocate the first part and the rest is just zeros. This
  * is why romsize and datasize are different. Also, this function takes its own
@@ -1242,6 +1249,7 @@ ssize_t rom_add_option(const char *file, int32_t bootindex)
 static void rom_reset(void *unused)
 {
     Rom *rom;
+    RomLoaderNotifyData notify;
 
     QTAILQ_FOREACH(rom, &roms, next) {
         if (rom->fw_file) {
@@ -1290,6 +1298,13 @@ static void rom_reset(void *unused)
         address_space_flush_icache_range(rom->as, rom->addr, rom->datasize);
 
         trace_loader_write_rom(rom->name, rom->addr, rom->datasize, rom->isrom);
+
+        notify = (RomLoaderNotifyData) {
+            .addr = rom->addr,
+            .len = rom->datasize,
+            .data = rom->data,
+        };
+        notifier_list_notify(&rom_loader_notifier, &notify);
     }
 }
 
diff --git a/include/hw/core/loader.h b/include/hw/core/loader.h
index d9431e8a8d12..fdfddfa7443e 100644
--- a/include/hw/core/loader.h
+++ b/include/hw/core/loader.h
@@ -342,6 +342,23 @@ void *rom_ptr_for_as(AddressSpace *as, hwaddr addr, size_t size);
 ssize_t rom_add_vga(const char *file);
 ssize_t rom_add_option(const char *file, int32_t bootindex);
 
+typedef struct RomLoaderNotifyData {
+    /* Address of the blob in guest memory */
+    hwaddr addr;
+    /* Length of the blob */
+    size_t len;
+    /* Blog data */
+    uint8_t *data;
+} RomLoaderNotifyData;
+
+/**
+ * rom_add_load_notifier - Add a notifier for loaded images
+ *
+ * Add a notifier that will be invoked with a RomLoaderNotifyData structure for
+ * each blob loaded into guest memory, after the blob is loaded.
+ */
+void rom_add_load_notifier(Notifier *notifier);
+
 /* This is the usual maximum in uboot, so if a uImage overflows this, it would
  * overflow on real hardware too. */
 #define UBOOT_MAX_DECOMPRESSED_BYTES (64 << 20)
-- 
2.43.0