Even if /run exists, it may not be world-writable. This is the case on
NixOS. Add an alternative option to lock the device node instead.
This should eventually be made the default when it has enjoyed more
testing.
Signed-off-by: Ahmad Fatoum <a.fat...@pengutronix.de>
---
configure.ac | 9 +++++++++
meson.build | 1 +
src/barebox-state.c | 30 ++++++++++++++++++------------
src/barebox-state/state.c | 4 ++++
src/barebox-state/state.h | 21 +++++++++++++++++++++
5 files changed, 53 insertions(+), 12 deletions(-)
diff --git a/configure.ac b/configure.ac
index be8967eb0809..117a1e169ba9 100644
--- a/configure.ac
+++ b/configure.ac
@@ -27,6 +27,15 @@ AS_IF([test "x${enable_state_backward_compatibility}" =
"xyes"], [
AC_DEFINE(CONFIG_STATE_BACKWARD_COMPATIBLE, [0])
])
+AC_ARG_ENABLE([lock-device],
+ AS_HELP_STRING([--enable-lock-device], [barebox-state: lock device
node instead of global lock in /run @<:@default=disabled@:>@]),
+ [], [enable_lock_device=no])
+AS_IF([test "x${enable_lock_device}" = "xyes"], [
+ AC_DEFINE(CONFIG_LOCK_DEVICE_NODE, [1], [lock device node backing
state.])
+], [
+ AC_DEFINE(CONFIG_LOCK_DEVICE_NODE, [0], [use global lock in /run.])
+])
+
AC_DEFINE(CONFIG_MTD, [1], [Statically define to be enabled to harmonize
barebox' & dt-utils' code base.])
AC_DEFINE(CONFIG_STATE, [1], [Statically define to be enabled to harmonize
barebox' & dt-utils' code base.])
diff --git a/meson.build b/meson.build
index 22b522ea4d0e..2fc13f55ed62 100644
--- a/meson.build
+++ b/meson.build
@@ -20,6 +20,7 @@ conf = configuration_data()
conf.set10('CONFIG_MTD', true)
conf.set10('CONFIG_STATE', true)
conf.set10('CONFIG_STATE_BACKWARD_COMPATIBLE',
get_option('state-backward-compatibility'))
+conf.set10('CONFIG_LOCK_DEVICE_NODE', get_option('lock-device'))
meson.add_dist_script(
find_program('check-news.sh').path(),
diff --git a/src/barebox-state.c b/src/barebox-state.c
index c5acd1f7780a..7cf2fbf070a9 100644
--- a/src/barebox-state.c
+++ b/src/barebox-state.c
@@ -499,6 +499,8 @@ int main(int argc, char *argv[])
printf(PACKAGE_STRING "\n");
printf("Configured with build-time option
'--%s-state-backward-compatibility'.\n",
(CONFIG_STATE_BACKWARD_COMPATIBLE) ? "enable" :
"disable");
+ printf("
'--%s-lock-device-node'.\n",
+ (CONFIG_LOCK_DEVICE_NODE) ? "enable" :
"disable");
exit(0);
case 'g':
sg = xzalloc(sizeof(*sg));
@@ -568,17 +570,19 @@ int main(int argc, char *argv[])
++nr_states;
}
- lock_fd = open(BAREBOX_STATE_LOCKFILE, O_CREAT | O_RDWR, 0600);
- if (lock_fd < 0) {
- pr_err("Failed to open lock-file " BAREBOX_STATE_LOCKFILE "\n");
- exit(1);
- }
+ if (!IS_ENABLED(CONFIG_LOCK_DEVICE_NODE)) {
+ lock_fd = open(BAREBOX_STATE_LOCKFILE, O_CREAT | O_RDWR, 0600);
+ if (lock_fd < 0) {
+ pr_err("Failed to open lock-file "
BAREBOX_STATE_LOCKFILE "\n");
+ exit(1);
+ }
- ret = flock(lock_fd, LOCK_EX);
- if (ret < 0) {
- pr_err("Failed to lock " BAREBOX_STATE_LOCKFILE ": %m\n");
- close(lock_fd);
- exit(1);
+ ret = flock(lock_fd, LOCK_EX);
+ if (ret < 0) {
+ pr_err("Failed to lock " BAREBOX_STATE_LOCKFILE ":
%m\n");
+ close(lock_fd);
+ exit(1);
+ }
}
list_for_each_entry(state, &state_list.list, list) {
@@ -700,8 +704,10 @@ int main(int argc, char *argv[])
ret = 0;
out_unlock:
- flock(lock_fd, LOCK_UN);
- close(lock_fd);
+ if (!IS_ENABLED(CONFIG_LOCK_DEVICE_NODE)) {
+ flock(lock_fd, LOCK_UN);
+ close(lock_fd);
+ }
return ret;
}
diff --git a/src/barebox-state/state.c b/src/barebox-state/state.c
index 42ce88d3f161..371ae3959d6c 100644
--- a/src/barebox-state/state.c
+++ b/src/barebox-state/state.c
@@ -664,6 +664,10 @@ struct state *state_new_from_node(struct device_node
*node, bool readonly)
pr_debug("%s: backend resolved to %s %lld %zu\n", node->full_name,
state->backend_path, (long long)offset, size);
+ /* will be released on program exit */
+ if (IS_ENABLED(CONFIG_LOCK_DEVICE_NODE))
+ (void)open_exclusive(state->backend_path, readonly ? O_RDONLY :
O_RDWR);
+
state->backend_reproducible_name =
of_get_reproducible_name(partition_node);
ret = of_property_read_string(node, "backend-type", &backend_type);
diff --git a/src/barebox-state/state.h b/src/barebox-state/state.h
index 4abfa84285c3..bbbc1892f846 100644
--- a/src/barebox-state/state.h
+++ b/src/barebox-state/state.h
@@ -3,6 +3,7 @@
#include <linux/types.h>
#include <linux/list.h>
#include <driver.h>
+#include <sys/file.h>
struct state;
struct mtd_info_user;
@@ -269,3 +270,23 @@ static inline int state_string_copy_to_raw(struct
state_string *string,
return 0;
}
+
+static inline int open_exclusive(const char *path, int flags)
+{
+ int fd;
+
+ fd = open(path, flags);
+ if (fd < 0)
+ return fd;
+
+ if (IS_ENABLED(CONFIG_LOCK_DEVICE_NODE)) {
+ int ret = flock(fd, LOCK_EX);
+ if (ret < 0) {
+ pr_err("Failed to lock %s: %d\n", path, -errno);
+ close(fd);
+ return -EWOULDBLOCK;
+ }
+ }
+
+ return fd;
+}
--
2.39.2
