Allow user supplied files to be inserted into the fw_cfg
device before starting the guest. Since fw_cfg_add_file()
already disallows duplicate fw_cfg file names, qemu will
exit with an error message if the user supplies multiple
blobs with the same fw_cfg file name, or if a blob name
collides with a fw_cfg name used internally by qemu.
Signed-off-by: Gabriel Somlo <so...@cmu.edu>
---
hw/nvram/fw_cfg.c | 48 +++++++++++++++++++++++++++++++++++++++++++++++
include/hw/nvram/fw_cfg.h | 4 ++++
qemu-options.hx | 10 ++++++++++
vl.c | 27 ++++++++++++++++++++++++++
4 files changed, 89 insertions(+)
diff --git a/hw/nvram/fw_cfg.c b/hw/nvram/fw_cfg.c
index 86f120e..70e9805 100644
--- a/hw/nvram/fw_cfg.c
+++ b/hw/nvram/fw_cfg.c
@@ -29,6 +29,7 @@
#include "trace.h"
#include "qemu/error-report.h"
#include "qemu/config-file.h"
+#include "hw/loader.h"
#define FW_CFG_SIZE 2
#define FW_CFG_NAME "fw_cfg"
@@ -549,6 +550,51 @@ static void fw_cfg_machine_ready(struct Notifier *n, void
*data)
}
+static struct FWCfgOption {
+ const char *name;
+ const char *file;
+} *fw_cfg_options;
+static int fw_cfg_num_options;
+
+void fw_cfg_option_add(QemuOpts *opts)
+{
+ const char *name = qemu_opt_get(opts, "name");
+ const char *file = qemu_opt_get(opts, "file");
+
+ if (name == NULL || *name == '\0' || file == NULL || *file == '\0') {
+ error_report("invalid argument value");
+ exit(1);
+ }
+
+ fw_cfg_options = g_realloc(fw_cfg_options, sizeof(struct FWCfgOption) *
+ (fw_cfg_num_options + 1));
+ fw_cfg_options[fw_cfg_num_options].name = name;
+ fw_cfg_options[fw_cfg_num_options].file = file;
+ fw_cfg_num_options++;
+}
+
+static void fw_cfg_options_insert(FWCfgState *s)
+{
+ int i, filesize;
+ const char *filename;
+ void *filebuf;
+
+ for (i = 0; i < fw_cfg_num_options; i++) {
+ filename = fw_cfg_options[i].file;
+ filesize = get_image_size(filename);
+ if (filesize == -1) {
+ error_report("Cannot read fw_cfg file %s", filename);
+ exit(1);
+ }
+ filebuf = g_malloc(filesize);
+ if (load_image(filename, filebuf) != filesize) {
+ error_report("Failed to load fw_cfg file %s", filename);
+ exit(1);
+ }
+ fw_cfg_add_file(s, fw_cfg_options[i].name, filebuf, filesize);
+ }
+}
+
static void fw_cfg_init1(DeviceState *dev)
{
@@ -560,6 +606,8 @@ static void fw_cfg_init1(DeviceState *dev)
qdev_init_nofail(dev);
+ fw_cfg_options_insert(s);
+
fw_cfg_add_bytes(s, FW_CFG_SIGNATURE, (char *)"QEMU", 4);
fw_cfg_add_bytes(s, FW_CFG_UUID, qemu_uuid, 16);
fw_cfg_add_i16(s, FW_CFG_NOGRAPHIC, (uint16_t)(display_type ==
DT_NOGRAPHIC));
diff --git a/include/hw/nvram/fw_cfg.h b/include/hw/nvram/fw_cfg.h
index f11d7d5..20a62d4 100644
--- a/include/hw/nvram/fw_cfg.h
+++ b/include/hw/nvram/fw_cfg.h
@@ -7,6 +7,7 @@
#include "exec/hwaddr.h"
#include "qemu/typedefs.h"
+#include "qemu/option.h"
#endif
#define FW_CFG_SIGNATURE 0x00
@@ -76,6 +77,9 @@ void fw_cfg_add_file_callback(FWCfgState *s, const char
*filename,
void *data, size_t len);
void *fw_cfg_modify_file(FWCfgState *s, const char *filename, void *data,
size_t len);
+
+void fw_cfg_option_add(QemuOpts *opts);
+
FWCfgState *fw_cfg_init_io(uint32_t iobase);
FWCfgState *fw_cfg_init_mem(hwaddr ctl_addr, hwaddr data_addr);
FWCfgState *fw_cfg_init_mem_wide(hwaddr ctl_addr, hwaddr data_addr,
diff --git a/qemu-options.hx b/qemu-options.hx
index 3c852f1..94ce91b 100644
--- a/qemu-options.hx
+++ b/qemu-options.hx
@@ -2668,6 +2668,16 @@ STEXI
@table @option
ETEXI
+DEF("fw_cfg", HAS_ARG, QEMU_OPTION_fwcfg,
+ "-fw_cfg name=<name>,file=<file>\n"
+ " add named fw_cfg blob from file\n",
+ QEMU_ARCH_ALL)
+STEXI
+@item -fw_cfg name=@var{name},file=@var{file}
+@findex -fw_cfg
+Add named fw_cfg blob from file
+ETEXI
+
DEF("serial", HAS_ARG, QEMU_OPTION_serial, \
"-serial dev redirect the serial port to char device 'dev'\n",
QEMU_ARCH_ALL)
diff --git a/vl.c b/vl.c
index 694deb4..6a30e61 100644
--- a/vl.c
+++ b/vl.c
@@ -490,6 +490,25 @@ static QemuOptsList qemu_semihosting_config_opts = {
},
};
+static QemuOptsList qemu_fw_cfg_opts = {
+ .name = "fw_cfg",
+ .implied_opt_name = "name",
+ .head = QTAILQ_HEAD_INITIALIZER(qemu_fw_cfg_opts.head),
+ .desc = {
+ {
+ .name = "name",
+ .type = QEMU_OPT_STRING,
+ .help = "Sets the fw_cfg name of the blob to be inserted",
+ }, {
+ .name = "file",
+ .type = QEMU_OPT_STRING,
+ .help = "Sets the name of the file from which\n"
+ "the fw_cfg blob will be loaded",
+ },
+ { /* end of list */ }
+ },
+};
+
/**
* Get machine options
*
@@ -2804,6 +2823,7 @@ int main(int argc, char **argv, char **envp)
qemu_add_opts(&qemu_numa_opts);
qemu_add_opts(&qemu_icount_opts);
qemu_add_opts(&qemu_semihosting_config_opts);
+ qemu_add_opts(&qemu_fw_cfg_opts);
runstate_init();
@@ -3420,6 +3440,13 @@ int main(int argc, char **argv, char **envp)
}
do_smbios_option(opts);
break;
+ case QEMU_OPTION_fwcfg:
+ opts = qemu_opts_parse(qemu_find_opts("fw_cfg"), optarg, 0);
+ if (opts == NULL) {
+ exit(1);
+ }
+ fw_cfg_option_add(opts);
+ break;
case QEMU_OPTION_enable_kvm:
olist = qemu_find_opts("machine");
qemu_opts_parse(olist, "accel=kvm", 0);
--
2.1.0
