[OSS-Tools] [PATCH 1/3] state: backend: direct: open block device in read-only mode if possible

[Ahmad Fatoum <a.fatoum@pengutronix.de>]

We unconditionally open the device backing a direct bucket in read-write
mode. The barebox_state utility already populates struct
state_backend_storage::readonly though, which we could consult at device
open time. Do so. This could possibly be done for MTD as well, but until
that's tested, for now, we do it only for the direct backend meant for
use with block devices.

Tested-by: Ulrich Ölmann <u.oelmann@pengutronix.de>
Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
---
 src/barebox-state/backend_bucket_direct.c | 5 +++--
 src/barebox-state/backend_storage.c       | 2 +-
 src/barebox-state/state.c                 | 6 +++---
 src/barebox-state/state.h                 | 3 ++-
 4 files changed, 9 insertions(+), 7 deletions(-)

diff --git a/src/barebox-state/backend_bucket_direct.c b/src/barebox-state/backend_bucket_direct.c
index 4522f0170f3d..48c1596c9add 100644
--- a/src/barebox-state/backend_bucket_direct.c
+++ b/src/barebox-state/backend_bucket_direct.c
@@ -164,12 +164,13 @@ static void state_backend_bucket_direct_free(struct
 
 int state_backend_bucket_direct_create(struct device_d *dev, const char *path,
 				       struct state_backend_storage_bucket **bucket,
-				       off_t offset, ssize_t max_size)
+				       off_t offset, ssize_t max_size,
+				       bool readonly)
 {
 	int fd;
 	struct state_backend_storage_bucket_direct *direct;
 
-	fd = open(path, O_RDWR);
+	fd = open(path, readonly ? O_RDONLY : O_RDWR);
 	if (fd < 0) {
 		dev_err(dev, "Failed to open file '%s', %d\n", path, -errno);
 		return -errno;
diff --git a/src/barebox-state/backend_storage.c b/src/barebox-state/backend_storage.c
index 509427f16f1d..39c2b9803f2d 100644
--- a/src/barebox-state/backend_storage.c
+++ b/src/barebox-state/backend_storage.c
@@ -324,7 +324,7 @@ static int state_storage_file_buckets_init(struct state_backend_storage *storage
 		offset = storage->offset + n * stridesize;
 		ret = state_backend_bucket_direct_create(storage->dev, storage->path,
 							 &bucket, offset,
-							 stridesize);
+							 stridesize, storage->readonly);
 		if (ret) {
 			dev_warn(storage->dev, "Failed to create direct bucket at '%s' offset %lld\n",
 				 storage->path, (long long) offset);
diff --git a/src/barebox-state/state.c b/src/barebox-state/state.c
index f528b3e19f21..7fa10f2eeb6b 100644
--- a/src/barebox-state/state.c
+++ b/src/barebox-state/state.c
@@ -650,14 +650,14 @@ struct state *state_new_from_node(struct device_node *node, bool readonly)
 	if (ret)
 		goto out_release_state;
 
+	if (readonly)
+		state_backend_set_readonly(state);
+
 	ret = state_storage_init(state, state->backend_path, offset,
 				 size, stridesize, storage_type);
 	if (ret)
 		goto out_release_state;
 
-	if (readonly)
-		state_backend_set_readonly(state);
-
 	ret = state_from_node(state, node, 1);
 	if (ret) {
 		goto out_release_state;
diff --git a/src/barebox-state/state.h b/src/barebox-state/state.h
index 912d6d484823..2e9b4b83f093 100644
--- a/src/barebox-state/state.h
+++ b/src/barebox-state/state.h
@@ -227,7 +227,8 @@ void state_backend_set_readonly(struct state *state);
 void state_storage_free(struct state_backend_storage *storage);
 int state_backend_bucket_direct_create(struct device_d *dev, const char *path,
 				       struct state_backend_storage_bucket **bucket,
-				       off_t offset, ssize_t max_size);
+				       off_t offset, ssize_t max_size,
+				       bool readonly);
 int state_storage_write(struct state_backend_storage *storage,
 			const void * buf, ssize_t len);
 int state_storage_read(struct state_backend_storage *storage,
-- 
2.39.2