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-rw-r--r--Documentation/user/variables.rst41
-rw-r--r--commands/Kconfig14
-rw-r--r--commands/Makefile1
-rw-r--r--commands/loadenv.c11
-rw-r--r--commands/nv.c84
-rw-r--r--common/environment.c1
-rw-r--r--common/globalvar.c173
-rw-r--r--common/startup.c2
-rw-r--r--include/globalvar.h12
9 files changed, 336 insertions, 3 deletions
diff --git a/Documentation/user/variables.rst b/Documentation/user/variables.rst
index a13de1b..974ab88 100644
--- a/Documentation/user/variables.rst
+++ b/Documentation/user/variables.rst
@@ -25,6 +25,47 @@ other variable. You can also directly assign a value during creation::
to assigning a value with ``global.myvar1=foobar``, but the latter fails when
a variable has not been created before.
+.. _config_device:
+
+Non volatile variables
+----------------------
+
+Additionally to global variables barebox also has non volatile (nv) variables.
+Unlike the global variables the config variables are persistent over reboots.
+
+Each nv variable is linked with the global variable of the same name.
+Whenever the nv variable changes its value the corresponding global
+variable also changes its value. The other way round though is not true:
+Changing a global variable does not change the corresponding nv variable.
+This means that changing a global variable changes the behaviour for the
+currently running barebox, while changing a nv variable changes the
+behaviour persistently over reboots.
+
+nv variables can be created or removed with the :ref:`command_nv`
+command. The nv variables are made persistent using the environment
+facilities of barebox, so a :ref:`saveenv` must be issued to store the actual
+values.
+
+examples:
+
+.. code-block:: sh
+
+ barebox@Phytec phyCARD-i.MX27:/ devinfo nv
+ barebox@Phytec phyCARD-i.MX27:/ nv model=myboard
+ barebox@myboard:/ devinfo nv
+ Parameters:
+ model: myboard
+ barebox@myboard:/ devinfo global
+ Parameters:
+ [...]
+ model: myboard
+ [...]
+ barebox@myboard:/ global.model=yourboard
+ barebox@yourboard:/ devinfo nv
+ Parameters:
+ model: myboard
+ barebox@yourboard:/
+
.. _magicvars:
Magic variables
diff --git a/commands/Kconfig b/commands/Kconfig
index bef5847..cf32548 100644
--- a/commands/Kconfig
+++ b/commands/Kconfig
@@ -674,6 +674,20 @@ endmenu
menu "Environment"
+config CMD_NV
+ select GLOBALVAR
+ tristate
+ prompt "nv"
+ help
+ create, set or remove non volatile variables.
+
+ Usage: nv [-r] VAR[=VALUE]
+
+ Add a new config non volatile named VAR, optionally set to VALUE.
+
+ Options:
+ -r remove a non volatile variable
+
config CMD_EXPORT
depends on ENVIRONMENT_VARIABLES
tristate
diff --git a/commands/Makefile b/commands/Makefile
index be17496..b4fc3d3 100644
--- a/commands/Makefile
+++ b/commands/Makefile
@@ -107,3 +107,4 @@ obj-$(CONFIG_CMD_HWCLOCK) += hwclock.o
obj-$(CONFIG_CMD_USBGADGET) += usbgadget.o
obj-$(CONFIG_CMD_FIRMWARELOAD) += firmwareload.o
obj-$(CONFIG_CMD_CMP) += cmp.o
+obj-$(CONFIG_CMD_NV) += nv.o
diff --git a/commands/loadenv.c b/commands/loadenv.c
index 8b15af4..91ce5e7 100644
--- a/commands/loadenv.c
+++ b/commands/loadenv.c
@@ -27,12 +27,13 @@
#include <errno.h>
#include <fs.h>
#include <malloc.h>
+#include <globalvar.h>
static int do_loadenv(int argc, char *argv[])
{
char *filename = NULL, *dirname;
unsigned flags = 0;
- int opt;
+ int opt, ret;
int scrub = 0;
int defaultenv = 0;
@@ -97,9 +98,13 @@ static int do_loadenv(int argc, char *argv[])
printf("loading environment from %s\n", defaultenv ? "defaultenv" : filename);
if (defaultenv)
- return defaultenv_load(dirname, flags);
+ ret = defaultenv_load(dirname, flags);
else
- return envfs_load(filename, dirname, flags);
+ ret = envfs_load(filename, dirname, flags);
+
+ nvvar_load();
+
+ return ret;
}
BAREBOX_CMD_HELP_START(loadenv)
diff --git a/commands/nv.c b/commands/nv.c
new file mode 100644
index 0000000..8cebb85
--- /dev/null
+++ b/commands/nv.c
@@ -0,0 +1,84 @@
+/*
+ * nv.c - non volatile shell variables
+ *
+ * Copyright (c) 2014 Sascha Hauer <s.hauer@pengutronix.de>, Pengutronix
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ */
+#include <common.h>
+#include <malloc.h>
+#include <command.h>
+#include <globalvar.h>
+#include <environment.h>
+#include <getopt.h>
+
+static int do_nv(int argc, char *argv[])
+{
+ int opt;
+ int do_remove = 0;
+ int ret;
+ char *value;
+
+ while ((opt = getopt(argc, argv, "r")) > 0) {
+ switch (opt) {
+ case 'r':
+ do_remove = 1;
+ break;
+ default:
+ return COMMAND_ERROR_USAGE;
+ }
+ }
+
+ if (argc == optind) {
+ nvvar_print();
+ return 0;
+ }
+
+ argc -= optind;
+ argv += optind;
+
+ if (argc != 1)
+ return COMMAND_ERROR_USAGE;
+
+ value = strchr(argv[0], '=');
+ if (value) {
+ *value = 0;
+ value++;
+ }
+
+ if (do_remove)
+ ret = nvvar_remove(argv[0]);
+ else
+ ret = nvvar_add(argv[0], value);
+
+ return ret;
+}
+
+BAREBOX_CMD_HELP_START(nv)
+BAREBOX_CMD_HELP_TEXT("Add a new non volatile variable named VAR, optionally set to VALUE.")
+BAREBOX_CMD_HELP_TEXT("non volatile variables are persistent variables that overwrite the")
+BAREBOX_CMD_HELP_TEXT("global variables of the same name. Their value is saved with")
+BAREBOX_CMD_HELP_TEXT("'saveenv'.")
+BAREBOX_CMD_HELP_TEXT("")
+BAREBOX_CMD_HELP_TEXT("Options:")
+BAREBOX_CMD_HELP_OPT("-r", "remove a non volatile variable")
+BAREBOX_CMD_HELP_END
+
+BAREBOX_CMD_START(nv)
+ .cmd = do_nv,
+ BAREBOX_CMD_DESC("create or set non volatile variables")
+ BAREBOX_CMD_OPTS("[-r] VAR[=VALUE]")
+ BAREBOX_CMD_GROUP(CMD_GRP_ENV)
+ BAREBOX_CMD_HELP(cmd_nv_help)
+BAREBOX_CMD_END
diff --git a/common/environment.c b/common/environment.c
index a04b1fa..2639411 100644
--- a/common/environment.c
+++ b/common/environment.c
@@ -603,6 +603,7 @@ int envfs_load(const char *filename, const char *dir, unsigned flags)
goto out;
ret = 0;
+
out:
close(envfd);
free(buf);
diff --git a/common/globalvar.c b/common/globalvar.c
index c72f147..ec23c24 100644
--- a/common/globalvar.c
+++ b/common/globalvar.c
@@ -5,6 +5,9 @@
#include <init.h>
#include <environment.h>
#include <magicvar.h>
+#include <fs.h>
+#include <fcntl.h>
+#include <libfile.h>
#include <generated/utsrelease.h>
struct device_d global_device = {
@@ -12,6 +15,11 @@ struct device_d global_device = {
.id = DEVICE_ID_SINGLE,
};
+struct device_d nv_device = {
+ .name = "nv",
+ .id = DEVICE_ID_SINGLE,
+};
+
int globalvar_add(const char *name,
int (*set)(struct device_d *dev, struct param_d *p, const char *val),
const char *(*get)(struct device_d *, struct param_d *p),
@@ -25,6 +33,170 @@ int globalvar_add(const char *name,
return 0;
}
+static int nv_save(const char *name, const char *val)
+{
+ int fd, ret;
+ char *fname;
+
+ ret = make_directory("/env/nv");
+ if (ret)
+ return ret;
+
+ fname = asprintf("/env/nv/%s", name);
+
+ fd = open(fname, O_CREAT | O_WRONLY | O_TRUNC);
+
+ free(fname);
+
+ if (fd < 0)
+ return fd;
+
+ fprintf(fd, "%s", val);
+
+ close(fd);
+
+ return 0;
+}
+
+static int nv_set(struct device_d *dev, struct param_d *p, const char *val)
+{
+ struct param_d *gp;
+ int ret;
+
+ if (!val)
+ val = "";
+
+ gp = get_param_by_name(&global_device, p->name);
+ if (!gp)
+ return -EINVAL;
+
+ ret = gp->set(&global_device, gp, val);
+ if (ret)
+ return ret;
+
+ free(p->value);
+ p->value = xstrdup(val);
+
+ return nv_save(p->name, val);
+}
+
+static const char *nv_get(struct device_d *dev, struct param_d *p)
+{
+ return p->value ? p->value : "";
+}
+
+int nvvar_add(const char *name, const char *value)
+{
+ struct param_d *p, *gp;
+ int ret;
+
+ gp = get_param_by_name(&nv_device, name);
+ if (gp) {
+ ret = dev_set_param(&global_device, name, value);
+ if (ret)
+ return ret;
+
+ ret = dev_set_param(&nv_device, name, value);
+ if (ret)
+ return ret;
+
+ return 0;
+ }
+
+ ret = globalvar_add_simple(name, value);
+ if (ret && ret != -EEXIST)
+ return ret;
+
+ p = dev_add_param(&nv_device, name, nv_set, nv_get, 0);
+ if (IS_ERR(p))
+ return PTR_ERR(p);
+
+ if (value) {
+ ret = dev_set_param(&global_device, name, value);
+ if (ret)
+ return ret;
+ } else {
+ value = dev_get_param(&global_device, name);
+ if (!value)
+ value = "";
+ }
+
+ p->value = xstrdup(value);
+
+ return nv_save(p->name, value);
+}
+
+int nvvar_remove(const char *name)
+{
+ struct param_d *p;
+ char *fname;
+
+ p = get_param_by_name(&nv_device, name);
+ if (!p)
+ return -ENOENT;
+
+ fname = asprintf("/env/nv/%s", p->name);
+ unlink(fname);
+ free(fname);
+
+ list_del(&p->list);
+ free(p->name);
+ free(p);
+
+ return 0;
+}
+
+int nvvar_load(void)
+{
+ char *val;
+ int ret;
+ DIR *dir;
+ struct dirent *d;
+
+ dir = opendir("/env/nv");
+ if (!dir)
+ return -ENOENT;
+
+ while ((d = readdir(dir))) {
+ if (!strcmp(d->d_name, ".") || !strcmp(d->d_name, ".."))
+ continue;
+
+ val = read_file_line("/env/nv/%s", d->d_name);
+
+ pr_debug("%s: Setting \"%s\" to \"%s\"\n",
+ __func__, d->d_name, val);
+
+ ret = nvvar_add(d->d_name, val);
+ if (ret)
+ pr_err("failed to create nv variable %s: %s\n",
+ d->d_name, strerror(-ret));
+ }
+
+ closedir(dir);
+
+ return 0;
+}
+
+static void device_param_print(struct device_d *dev)
+{
+ struct param_d *param;
+
+ list_for_each_entry(param, &dev->parameters, list) {
+ const char *p = dev_get_param(dev, param->name);
+ const char *nv = NULL;
+
+ if (dev != &nv_device)
+ nv = dev_get_param(&nv_device, param->name);
+
+ printf("%s%s: %s\n", nv ? "* " : " ", param->name, p);
+ }
+}
+
+void nvvar_print(void)
+{
+ device_param_print(&nv_device);
+}
+
/*
* globalvar_get_match
*
@@ -87,6 +259,7 @@ int globalvar_add_simple(const char *name, const char *value)
static int globalvar_init(void)
{
register_device(&global_device);
+ register_device(&nv_device);
globalvar_add_simple("version", UTS_RELEASE);
diff --git a/common/startup.c b/common/startup.c
index f164142..2b92efc 100644
--- a/common/startup.c
+++ b/common/startup.c
@@ -40,6 +40,7 @@
#include <envfs.h>
#include <asm/sections.h>
#include <uncompress.h>
+#include <globalvar.h>
extern initcall_t __barebox_initcalls_start[], __barebox_early_initcalls_end[],
__barebox_initcalls_end[];
@@ -84,6 +85,7 @@ void __noreturn start_barebox(void)
defaultenv_load("/env", 0);
envfs_load(default_environment_path, "/env", 0);
+ nvvar_load();
}
if (IS_ENABLED(CONFIG_COMMAND_SUPPORT)) {
diff --git a/include/globalvar.h b/include/globalvar.h
index 456e8cd..56b23fd 100644
--- a/include/globalvar.h
+++ b/include/globalvar.h
@@ -72,6 +72,12 @@ static inline int globalvar_add_simple_ip(const char *name,
return 0;
}
+
+int nvvar_load(void);
+void nvvar_print(void);
+int nvvar_add(const char *name, const char *value);
+int nvvar_remove(const char *name);
+
#else
static inline int globalvar_add_simple(const char *name, const char *value)
{
@@ -116,6 +122,12 @@ static inline char *globalvar_get_match(const char *match, const char *separator
}
static inline void globalvar_set_match(const char *match, const char *val) {}
+
+static inline int nvvar_load(void)
+{
+ return 0;
+}
+
#endif
#endif /* __GLOBALVAR_H */