sandbox: implement reset
Up to now the sandbox would shutdown upon a cold reset request. Instead it
should be reset.
In our coding we use static variables like LIST_HEAD(efi_obj_list). A reset
can occur at any time, e.g. via an UEFI binary calling the reset service.
The only safe way to return to an initial state is to relaunch the U-Boot
binary.
The reset implementation uses execv() to relaunch U-Boot.
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/sandbox/cpu/os.c b/arch/sandbox/cpu/os.c
index 7e474d6..0d8efd8 100644
--- a/arch/sandbox/cpu/os.c
+++ b/arch/sandbox/cpu/os.c
@@ -822,3 +822,9 @@
return base;
}
+
+void os_relaunch(char *argv[])
+{
+ execv(argv[0], argv);
+ os_exit(1);
+}
diff --git a/arch/sandbox/cpu/start.c b/arch/sandbox/cpu/start.c
index 58ada13..a03e5aa 100644
--- a/arch/sandbox/cpu/start.c
+++ b/arch/sandbox/cpu/start.c
@@ -5,6 +5,7 @@
#include <common.h>
#include <command.h>
+#include <dm/root.h>
#include <errno.h>
#include <init.h>
#include <os.h>
@@ -19,6 +20,8 @@
DECLARE_GLOBAL_DATA_PTR;
+static char **os_argv;
+
/* Compare two options so that they can be sorted into alphabetical order */
static int h_compare_opt(const void *p1, const void *p2)
{
@@ -403,12 +406,35 @@
printf("\n");
}
+void sandbox_reset(void)
+{
+ /* Do this here while it still has an effect */
+ os_fd_restore();
+ if (state_uninit())
+ os_exit(2);
+
+ if (dm_uninit())
+ os_exit(2);
+
+ /* Restart U-Boot */
+ os_relaunch(os_argv);
+}
+
int main(int argc, char *argv[])
{
struct sandbox_state *state;
gd_t data;
int ret;
+ /*
+ * Copy argv[] so that we can pass the arguments in the original
+ * sequence when resetting the sandbox.
+ */
+ os_argv = calloc(argc + 1, sizeof(char *));
+ if (!os_argv)
+ os_exit(1);
+ memcpy(os_argv, argv, sizeof(char *) * (argc + 1));
+
memset(&data, '\0', sizeof(data));
gd = &data;
gd->arch.text_base = os_find_text_base();
diff --git a/arch/sandbox/cpu/state.c b/arch/sandbox/cpu/state.c
index 34b6fff..59f37fa 100644
--- a/arch/sandbox/cpu/state.c
+++ b/arch/sandbox/cpu/state.c
@@ -358,6 +358,7 @@
/* No reset yet, so mark it as such. Always allow power reset */
state->last_sysreset = SYSRESET_COUNT;
state->sysreset_allowed[SYSRESET_POWER_OFF] = true;
+ state->sysreset_allowed[SYSRESET_COLD] = true;
state->allow_memio = false;
memset(&state->wdt, '\0', sizeof(state->wdt));
diff --git a/arch/sandbox/include/asm/u-boot-sandbox.h b/arch/sandbox/include/asm/u-boot-sandbox.h
index 798d003..73b1897 100644
--- a/arch/sandbox/include/asm/u-boot-sandbox.h
+++ b/arch/sandbox/include/asm/u-boot-sandbox.h
@@ -84,6 +84,16 @@
*/
int sandbox_read_fdt_from_file(void);
+/**
+ * sandbox_reset() - reset sandbox
+ *
+ * This functions implements the cold reboot of the sandbox. It relaunches the
+ * U-Boot binary with the same command line parameters as the original call.
+ * The PID of the process stays the same. All file descriptors that have not
+ * been opened with O_CLOEXEC stay open including stdin, stdout, stderr.
+ */
+void sandbox_reset(void);
+
/* Exit sandbox (quit U-Boot) */
void sandbox_exit(void);
diff --git a/drivers/sysreset/sysreset_sandbox.c b/drivers/sysreset/sysreset_sandbox.c
index 71cabd1..7026a48 100644
--- a/drivers/sysreset/sysreset_sandbox.c
+++ b/drivers/sysreset/sysreset_sandbox.c
@@ -56,6 +56,9 @@
switch (type) {
case SYSRESET_COLD:
state->last_sysreset = type;
+ if (!state->sysreset_allowed[type])
+ return -EACCES;
+ sandbox_reset();
break;
case SYSRESET_POWER_OFF:
state->last_sysreset = type;
diff --git a/include/os.h b/include/os.h
index 1874ae6..88dfb71 100644
--- a/include/os.h
+++ b/include/os.h
@@ -355,4 +355,19 @@
*/
void *os_find_text_base(void);
+/**
+ * os_relaunch() - restart the sandbox
+ *
+ * This functions is used to implement the cold reboot of the sand box.
+ * @argv[0] specifies the binary that is started while the calling process
+ * stops immediately. If the new binary cannot be started, the process is
+ * terminated and 1 is set as shell return code.
+ *
+ * The PID of the process stays the same. All file descriptors that have not
+ * been opened with O_CLOEXEC stay open including stdin, stdout, stderr.
+ *
+ * @argv: NULL terminated list of command line parameters
+ */
+void os_relaunch(char *argv[]);
+
#endif