[PATCH 1/3] bbu: detect devices when devicefile has no /dev/ prefix as well

[PATCH 1/3] bbu: detect devices when devicefile has no /dev/ prefix as well

[Ahmad Fatoum]

Functions like imx6_bbu_internal_mmcboot_register_handler() are called
with devicefile either being the cdev name or with a full path.

There is no harm in trying to detect the devicefile in the former case
as well, so do it unconditionally and simplify the function as a result.

Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
---
 common/bbu.c | 20 ++++++--------------
 1 file changed, 6 insertions(+), 14 deletions(-)

diff --git a/common/bbu.c b/common/bbu.c
index 39db87e823d9..00d415bcf826 100644
--- a/common/bbu.c
+++ b/common/bbu.c
@@ -43,27 +43,19 @@ void bbu_append_handlers_to_file_list(struct file_list *files)
 	struct bbu_handler *handler;
 
 	list_for_each_entry(handler, &bbu_image_handlers, list) {
-		const char *cdevname, *devpath;
-		char *buf = NULL;
+		const char *devicefile;
 		struct stat s;
 
-		devpath = handler->devicefile;
+		devicefile = handler->devicefile;
 
-		if (strstarts(devpath, "/dev/")) {
-			cdevname = devpath_to_name(devpath);
-			device_detect_by_name(cdevname);
+		device_detect_by_name(devpath_to_name(devicefile));
 
-			devpath = buf = basprintf("/dev/%s", cdevname);
-		}
-
-		if (stat(devpath, &s) == 0) {
-			append_bbu_entry(handler->name, devpath, files);
+		if (stat(devicefile, &s) == 0) {
+			append_bbu_entry(handler->name, devicefile, files);
 		} else {
 			pr_info("Skipping handler bbu-%s: %s unavailable\n",
-				handler->name, devpath);
+				handler->name, devicefile);
 		}
-
-		free(buf);
 	}
 }
 
-- 
2.47.3

[PATCH 2/3] treewide: replace open-coded variants of devpath_to_name

[Ahmad Fatoum]

Instead of opencoding this at multiple places, use the helper we have
for it.

Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
---
 commands/findmnt.c        | 2 +-
 common/bootscan.c         | 2 +-
 common/imx-bbu-nand-fcb.c | 2 +-
 3 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/commands/findmnt.c b/commands/findmnt.c
index a531b1a95a83..b1c323ebbff2 100644
--- a/commands/findmnt.c
+++ b/commands/findmnt.c
@@ -92,7 +92,7 @@ static int do_findmnt(int argc, char *argv[])
 				continue;
 
 			backingstore = target->backingstore;
-			backingstore += str_has_prefix(backingstore, "/dev/");
+			backingstore = devpath_to_name(backingstore);
 
 			if (streq_ptr(backingstore, cdev->name)) {
 				print_header(&header_printed);
diff --git a/common/bootscan.c b/common/bootscan.c
index 813d6d242a08..faaceaa22152 100644
--- a/common/bootscan.c
+++ b/common/bootscan.c
@@ -145,7 +145,7 @@ static int boot_scan_devicename(struct bootscanner *scanner,
 	pr_debug("%s(%s): %s\n", __func__, scanner->name, devname);
 
 	/* Support both boot /dev/disk0.rootfs and boot disk0.rootfs */
-	devname += str_has_prefix(devname, "/dev/");
+	devname = devpath_to_name(devname);
 
 	device_detect_by_name(devname);
 
diff --git a/common/imx-bbu-nand-fcb.c b/common/imx-bbu-nand-fcb.c
index 7593cd27fec9..0ca5782a702e 100644
--- a/common/imx-bbu-nand-fcb.c
+++ b/common/imx-bbu-nand-fcb.c
@@ -1232,7 +1232,7 @@ static int imx_bbu_nand_update(struct bbu_handler *handler, struct bbu_data *dat
 	}
 
 	/* Support both boot /dev/nand0.barebox and boot nand0.barebox */
-	devname += str_has_prefix(devname, "/dev/");
+	devname = devpath_to_name(devname);
 
 	device_detect_by_name(devname);
 
-- 
2.47.3

[PATCH 3/3] fs: implement new resolve_fsdevice_path helper

[Ahmad Fatoum]

For use by the EFI loader, we will want to split off the file path
within a device from the device path.

As we have no function that generates a path relative to a mountpoint's
root, add a function that does this.

Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
---
 fs/fs.c      | 25 +++++++++++++++++++++++++
 include/fs.h |  1 +
 2 files changed, 26 insertions(+)

diff --git a/fs/fs.c b/fs/fs.c
index 28378989f91b..77f22d69ea49 100644
--- a/fs/fs.c
+++ b/fs/fs.c
@@ -2454,6 +2454,31 @@ struct fs_device *get_fsdevice_by_path(int dirfd, const char *pathname)
 	return fsdev;
 }
 
+struct fs_device *resolve_fsdevice_path(int dirfd, const char *pathname, char **filepath)
+{
+	struct fs_device *fsdev;
+	char *res = NULL;
+	struct path path;
+	int ret;
+
+	fsdev = get_fsdevice_by_path(dirfd, pathname);
+	if (!fsdev)
+		return NULL;
+
+	ret = filename_lookup(dirfd, getname(pathname), LOOKUP_FOLLOW, &path);
+	if (ret)
+		goto out;
+
+	res = dpath(path.dentry, fsdev->vfsmount.mnt_root);
+	if (res)
+		*filepath = res;
+
+	path_put(&path);
+out:
+	errno_set(ret);
+	return res ? fsdev : NULL;
+}
+
 static int vfs_rmdir(struct inode *dir, struct dentry *dentry)
 {
 	int error;
diff --git a/include/fs.h b/include/fs.h
index b9bd14da81a7..9c3c8d95123a 100644
--- a/include/fs.h
+++ b/include/fs.h
@@ -141,6 +141,7 @@ void cdev_print(const struct cdev *cdev);
 char *canonicalize_path(int dirfd, const char *pathname);
 
 struct fs_device *get_fsdevice_by_path(int dirfd, const char *path);
+struct fs_device *resolve_fsdevice_path(int dirfd, const char *pathname, char **filepath);
 
 const char *get_mounted_path(const char *path);
 
-- 
2.47.3

Re: [PATCH 1/3] bbu: detect devices when devicefile has no /dev/ prefix as well

[Sascha Hauer]

On Thu, 11 Dec 2025 16:18:14 +0100, Ahmad Fatoum wrote:
> Functions like imx6_bbu_internal_mmcboot_register_handler() are called
> with devicefile either being the cdev name or with a full path.
> 
> There is no harm in trying to detect the devicefile in the former case
> as well, so do it unconditionally and simplify the function as a result.
> 
> 
> [...]

Applied, thanks!

[1/3] bbu: detect devices when devicefile has no /dev/ prefix as well
      https://git.pengutronix.de/cgit/barebox/commit/?id=56811a330c77 (link may not be stable)
[2/3] treewide: replace open-coded variants of devpath_to_name
      https://git.pengutronix.de/cgit/barebox/commit/?id=e9304ba3e0f1 (link may not be stable)
[3/3] fs: implement new resolve_fsdevice_path helper
      https://git.pengutronix.de/cgit/barebox/commit/?id=feb5291006ec (link may not be stable)

Best regards,
-- 
Sascha Hauer <s.hauer@pengutronix.de>