This patch allows handling an ELF memory-mapped, taking care
the reference count of the GMappedFile* passed through
rom_add_elf_program().
In this case, the 'data' pointer is not heap-allocated, so
we cannot free it.
Suggested-by: Paolo Bonzini <pbonz...@redhat.com>
Signed-off-by: Stefano Garzarella <sgarz...@redhat.com>
---
hw/core/loader.c | 37 ++++++++++++++++++++++++++++++-------
include/hw/elf_ops.h | 2 +-
include/hw/loader.h | 5 +++--
3 files changed, 34 insertions(+), 10 deletions(-)
diff --git a/hw/core/loader.c b/hw/core/loader.c
index 425bf69a99..637d448f42 100644
--- a/hw/core/loader.c
+++ b/hw/core/loader.c
@@ -836,6 +836,7 @@ struct Rom {
int isrom;
char *fw_dir;
char *fw_file;
+ GMappedFile *mapped_file;
bool committed;
@@ -846,10 +847,25 @@ struct Rom {
static FWCfgState *fw_cfg;
static QTAILQ_HEAD(, Rom) roms = QTAILQ_HEAD_INITIALIZER(roms);
-/* rom->data must be heap-allocated (do not use with rom_add_elf_program()) */
+/*
+ * rom->data can be heap-allocated or memory-mapped (e.g. when added with
+ * rom_add_elf_program())
+ */
+static void rom_free_data(Rom *rom)
+{
+ if (rom->mapped_file) {
+ g_mapped_file_unref(rom->mapped_file);
+ rom->mapped_file = NULL;
+ } else {
+ g_free(rom->data);
+ }
+
+ rom->data = NULL;
+}
+
static void rom_free(Rom *rom)
{
- g_free(rom->data);
+ rom_free_data(rom);
g_free(rom->path);
g_free(rom->name);
g_free(rom->fw_dir);
@@ -1057,10 +1073,12 @@ MemoryRegion *rom_add_blob(const char *name, const void
*blob, size_t len,
/* 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 seize the
- * memory ownership of "data", so we don't have to allocate and copy the
buffer.
+ * memory ownership of "data", increasing the reference count of "mapped_file",
+ * so we don't have to allocate and copy the buffer.
*/
-int rom_add_elf_program(const char *name, void *data, size_t datasize,
- size_t romsize, hwaddr addr, AddressSpace *as)
+int rom_add_elf_program(const char *name, GMappedFile *mapped_file, void *data,
+ size_t datasize, size_t romsize, hwaddr addr,
+ AddressSpace *as)
{
Rom *rom;
@@ -1071,6 +1089,12 @@ int rom_add_elf_program(const char *name, void *data,
size_t datasize,
rom->romsize = romsize;
rom->data = data;
rom->as = as;
+
+ if (mapped_file && data) {
+ g_mapped_file_ref(mapped_file);
+ rom->mapped_file = mapped_file;
+ }
+
rom_insert(rom);
return 0;
}
@@ -1105,8 +1129,7 @@ static void rom_reset(void *unused)
}
if (rom->isrom) {
/* rom needs to be written only once */
- g_free(rom->data);
- rom->data = NULL;
+ rom_free_data(rom);
}
/*
* The rom loader is really on the same level as firmware in the guest
diff --git a/include/hw/elf_ops.h b/include/hw/elf_ops.h
index 690f9238c8..fede37ee9c 100644
--- a/include/hw/elf_ops.h
+++ b/include/hw/elf_ops.h
@@ -525,7 +525,7 @@ static int glue(load_elf, SZ)(const char *name, int fd,
snprintf(label, sizeof(label), "phdr #%d: %s", i, name);
/* rom_add_elf_program() seize the ownership of 'data' */
- rom_add_elf_program(label, data, file_size, mem_size,
+ rom_add_elf_program(label, NULL, data, file_size, mem_size,
addr, as);
} else {
address_space_write(as ? as : &address_space_memory,
diff --git a/include/hw/loader.h b/include/hw/loader.h
index 3e1b3a4566..07fd9286e7 100644
--- a/include/hw/loader.h
+++ b/include/hw/loader.h
@@ -258,8 +258,9 @@ MemoryRegion *rom_add_blob(const char *name, const void
*blob, size_t len,
FWCfgCallback fw_callback,
void *callback_opaque, AddressSpace *as,
bool read_only);
-int rom_add_elf_program(const char *name, void *data, size_t datasize,
- size_t romsize, hwaddr addr, AddressSpace *as);
+int rom_add_elf_program(const char *name, GMappedFile *mapped_file, void *data,
+ size_t datasize, size_t romsize, hwaddr addr,
+ AddressSpace *as);
int rom_check_and_register_reset(void);
void rom_set_fw(FWCfgState *f);
void rom_set_order_override(int order);
--
2.20.1
