cmd: set filesize variable in ubi read

After a successful read of a UBI volume, the variable filesize is set
to the number of read bytes. To boot linux with a raw initramfs/initrd,
you must specify the exact size of the initramfs/initrd image in boot
command. If the initramfs/inird is read from UBI volume, $filesize is
required to access the number of read bytes.

Example:
  ubi read ${loadaddr} kernelvol
  ubi read ${fdtaddr} dtbvol
  ubi read ${initrd_addr} initrdvol
  bootz ${loadaddr} ${initrd_addr}:${filesize} ${fdt_addr}

Signed-off-by: Holger Dengler <dengler@linutronix.de>
Reviewed-by: Heiko Schocher <hs@denx.de>

diff --git a/cmd/ubi.c b/cmd/ubi.c
index 222be5a..ac9a582 100644 (file)
--- a/cmd/ubi.c
+++ b/cmd/ubi.c
@@ -334,6 +334,7 @@ int ubi_volume_read(char *volume, char *buf, size_t size)
        unsigned long long tmp;
        struct ubi_volume *vol;
        loff_t offp = 0;
+       size_t len_read;
 
        vol = ubi_find_volume(volume);
        if (vol == NULL)
@@ -373,6 +374,7 @@ int ubi_volume_read(char *volume, char *buf, size_t size)
        tmp = offp;
        off = do_div(tmp, vol->usable_leb_size);
        lnum = tmp;
+       len_read = size;
        do {
                if (off + len >= vol->usable_leb_size)
                        len = vol->usable_leb_size - off;
@@ -398,6 +400,9 @@ int ubi_volume_read(char *volume, char *buf, size_t size)
                len = size > tbuf_size ? tbuf_size : size;
        } while (size);
 
+       if (!size)
+               env_set_hex("filesize", len_read);
+
        free(tbuf);
        return err;
 }