[OSS-Tools] [PATCH 1/8] 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 458f2a91552b..4c5e1783c199 100644
--- a/src/barebox-state/backend_storage.c
+++ b/src/barebox-state/backend_storage.c
@@ -326,7 +326,7 @@ 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 4779574d2ee9..3174c84b8ded 100644
--- a/src/barebox-state/state.c
+++ b/src/barebox-state/state.c
@@ -649,14 +649,14 @@ 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 719f7e43c94c..4abfa84285c3 100644
--- a/src/barebox-state/state.h
+++ b/src/barebox-state/state.h
@@ -225,7 +225,8 @@ 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