make extroot functionality work with ubifs

http://patchwork.ozlabs.org/patch/420864/

Signed-off-by: Gergely Kiss <mail.gery@gmail.com>

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 5211bcdc8a18fb59fc2351767591411fd42c00f7..ba375f2cc62ffe6477fdc825624a0751882cf973 100644 (file)
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -48,7 +48,12 @@ TARGET_LINK_LIBRARIES(mount_root fstools)
 INSTALL(TARGETS mount_root RUNTIME DESTINATION sbin)
 
 ADD_EXECUTABLE(block block.c)
-TARGET_LINK_LIBRARIES(block blkid-tiny uci ubox blobmsg_json)
+IF(DEFINED CMAKE_UBIFS_EXTROOT)
+       ADD_DEFINITIONS(-DUBIFS_EXTROOT)
+       TARGET_LINK_LIBRARIES(block blkid-tiny uci ubox blobmsg_json ubi-utils)
+ELSE(DEFINED CMAKE_UBIFS_EXTROOT)
+       TARGET_LINK_LIBRARIES(block blkid-tiny uci ubox blobmsg_json)
+ENDIF(DEFINED CMAKE_UBIFS_EXTROOT)
 INSTALL(TARGETS block RUNTIME DESTINATION sbin)
 
 ADD_EXECUTABLE(jffs2reset jffs2reset.c)

diff --git a/block.c b/block.c
index 8bb77aa959f5ff21581c6b3aa13fa9a5e70616e1..6d187d1892ba84de1fe84927e9ac88ab646a83e3 100644 (file)
--- a/block.c
+++ b/block.c
@@ -36,6 +36,10 @@
 
 #include "libblkid-tiny/libblkid-tiny.h"
 
+#ifdef UBIFS_EXTROOT
+#include "libubi/libubi.h"
+#endif
+
 #define ERROR(fmt, ...) do { \
                syslog(LOG_ERR, fmt, ## __VA_ARGS__); \
                fprintf(stderr, "block: "fmt, ## __VA_ARGS__); \
@@ -823,13 +827,77 @@ static int find_block_mtd(char *name, char *part, int plen)
        return 0;
 }
 
+#ifdef UBIFS_EXTROOT
+static int find_ubi_vol(libubi_t libubi, char *name, int *dev_num, int *vol_id)
+{
+       int dev = 0;
+
+       while (ubi_dev_present(libubi, dev))
+       {
+               struct ubi_dev_info dev_info;
+               struct ubi_vol_info vol_info;
+
+               if (ubi_get_dev_info1(libubi, dev++, &dev_info))
+                       continue;
+               if (ubi_get_vol_info1_nm(libubi, dev_info.dev_num, name, &vol_info))
+                       continue;
+
+               *dev_num = dev_info.dev_num;
+               *vol_id = vol_info.vol_id;
+
+               return 0;
+       }
+
+       return -1;
+}
+
+static int find_block_ubi(libubi_t libubi, char *name, char *part, int plen)
+{
+       int dev_num;
+       int vol_id;
+       int err = -1;
+
+       err = find_ubi_vol(libubi, name, &dev_num, &vol_id);
+       if (!err)
+               snprintf(part, plen, "/dev/ubi%d_%d", dev_num, vol_id);
+
+       return err;
+}
+
+static int find_block_ubi_RO(libubi_t libubi, char *name, char *part, int plen)
+{
+       int dev_num;
+       int vol_id;
+       int err = -1;
+
+       err = find_ubi_vol(libubi, name, &dev_num, &vol_id);
+       if (!err)
+               snprintf(part, plen, "/dev/ubiblock%d_%d", dev_num, vol_id);
+
+       return err;
+}
+#endif
+
 static int check_extroot(char *path)
 {
        struct blkid_struct_probe *pr = NULL;
        char fs[32];
 
+#ifdef UBIFS_EXTROOT
+       if (find_block_mtd("rootfs", fs, sizeof(fs))) {
+               int err = -1;
+               libubi_t libubi;
+
+               libubi = libubi_open();
+               err = find_block_ubi_RO(libubi, "rootfs", fs, sizeof(fs));
+               libubi_close(libubi);
+               if (err)
+                       return -1;
+       }
+#else
        if (find_block_mtd("rootfs", fs, sizeof(fs)))
                return -1;
+#endif
 
        list_for_each_entry(pr, &devices, list) {
                if (!strcmp(pr->dev, fs)) {
@@ -933,6 +1001,9 @@ static int main_extroot(int argc, char **argv)
        char fs[32] = { 0 };
        char fs_data[32] = { 0 };
        int err = -1;
+#ifdef UBIFS_EXTROOT
+       libubi_t libubi;
+#endif
 
        if (!getenv("PREINIT"))
                return -1;
@@ -947,8 +1018,18 @@ static int main_extroot(int argc, char **argv)
 
        find_block_mtd("rootfs", fs, sizeof(fs));
        if (!fs[0]) {
+#ifdef UBIFS_EXTROOT
+               libubi = libubi_open();
+               find_block_ubi_RO(libubi, "rootfs", fs, sizeof(fs));
+               libubi_close(libubi);
+               if (!fs[0]) {
+                       ERROR("extroot: unable to locate rootfs mtdblock / ubiblock\n");
+                       return -2;
+               }
+#else
                ERROR("extroot: unable to locate rootfs mtdblock\n");
                return -2;
+#endif
        }
 
        pr = find_block_info(NULL, NULL, fs);
@@ -975,6 +1056,26 @@ static int main_extroot(int argc, char **argv)
                }
        }
 
+#ifdef UBIFS_EXTROOT
+       memset(fs_data, 0, sizeof(fs_data));
+       libubi = libubi_open();
+       find_block_ubi(libubi, "rootfs_data", fs_data, sizeof(fs_data));
+       libubi_close(libubi);
+       if (fs_data[0]) {
+               char cfg[] = "/tmp/ubifs_cfg";
+
+               mkdir_p(cfg);
+               if (!mount(fs_data, cfg, "ubifs", MS_NOATIME, NULL)) {
+                       err = mount_extroot(cfg);
+                       umount2(cfg, MNT_DETACH);
+               }
+               if (err < 0)
+                       rmdir("/tmp/overlay");
+               rmdir(cfg);
+               return err;
+       }
+#endif
+
        return mount_extroot(NULL);
 }