On 19.05.25 15:12, Joakim Tjernlund wrote:
> This enables mounting, like JFFS2, MTD devices by "label":
> mount -t squashfs mtd:appfs /tmp
> where mtd:appfs comes from:
> # > cat /proc/mtd
> dev: size erasesize name
> ...
> mtd22: 00750000 00010000 "appfs"
>
> Signed-off-by: Joakim Tjernlund <joakim.tjernlund@xxxxxxxxxxxx>
> ---
> fs/super.c | 26 ++++++++++++++++++++++++++
> 1 file changed, 26 insertions(+)
>
> diff --git a/fs/super.c b/fs/super.c
> index 97a17f9d9023..8c3aa2f05b42 100644
> --- a/fs/super.c
> +++ b/fs/super.c
> @@ -37,6 +37,7 @@
> #include <linux/user_namespace.h>
> #include <linux/fs_context.h>
> #include <uapi/linux/mount.h>
> +#include <linux/mtd/mtd.h>
> #include "internal.h"
>
> static int thaw_super_locked(struct super_block *sb, enum freeze_holder who);
> @@ -1595,6 +1596,30 @@ int setup_bdev_super(struct super_block *sb, int sb_flags,
> }
> EXPORT_SYMBOL_GPL(setup_bdev_super);
>
> +void translate_mtd_name(void)
How can that work doesn't it need the fs_context?
> +{
> +#ifdef CONFIG_MTD_BLOCK
> + if (!strncmp(fc->source, "mtd:", 4)) {
> + struct mtd_info *mtd;
> + char *blk_source;
> +
> + /* mount by MTD device name */
> + pr_debug("Block SB: name \"%s\"\n", fc->source);
> +
> + mtd = get_mtd_device_nm(fc->source + 4);
> + if (IS_ERR(mtd))
> + return -EINVAL;
> + blk_source = kmalloc(20, GFP_KERNEL);
> + if (!blk_source)
> + return -ENOMEM;
> + sprintf(blk_source, "/dev/mtdblock%d", mtd->index);
> + kfree(fc->source);
> + fc->source = blk_source;
> + pr_debug("MTD device:%s found\n", fc->source);
> + }
> +#endif
> +}
> +
> /**
> * get_tree_bdev_flags - Get a superblock based on a single block device
> * @fc: The filesystem context holding the parameters
> @@ -1612,6 +1637,7 @@ int get_tree_bdev_flags(struct fs_context *fc,
> if (!fc->source)
> return invalf(fc, "No source specified");
>
> + translate_mtd_name();
> error = lookup_bdev(fc->source, &dev);
> if (error) {
> if (!(flags & GET_TREE_BDEV_QUIET_LOOKUP))
