--- /dev/null
+From d83dc950b3ec1fbde33b23d42c5154091a74f4d9 Mon Sep 17 00:00:00 2001
+From: Robert Yang <liezhi.yang@windriver.com>
+Date: Mon, 23 Dec 2013 03:44:03 -0500
+Subject: [PATCH 09/11] misc/create_inode.c: handle hardlinks
+
+Create the inode and save the native inode number when we meet the hard
+link (st_nlink > 1) at the first time, use ext2fs_link() to link the
+name to the target inode number when we meet the same native inode
+number again.
+
+This algorithm is referred from the genext2fs.
+
+Upstream-Status: Backport
+
+Signed-off-by: Robert Yang <liezhi.yang@windriver.com>
+Reviewed-by: Darren Hart <dvhart@linux.intel.com>
+---
+ misc/create_inode.c | 88 +++++++++++++++++++++++++++++++++++++++++++++++++++
+ misc/create_inode.h | 18 +++++++++++
+ misc/mke2fs.c | 12 +++++++
+ 3 files changed, 118 insertions(+)
+
+diff --git a/misc/create_inode.c b/misc/create_inode.c
+index aad7354..763504d 100644
+--- a/misc/create_inode.c
++++ b/misc/create_inode.c
+@@ -18,6 +18,44 @@
+ #define S_BLKSIZE 512
+ #endif
+
++/* For saving the hard links */
++int hdlink_cnt = HDLINK_CNT;
++
++/* Link an inode number to a directory */
++static errcode_t add_link(ext2_ino_t parent_ino, ext2_ino_t ino, const char *name)
++{
++ struct ext2_inode inode;
++ errcode_t retval;
++
++ retval = ext2fs_read_inode(current_fs, ino, &inode);
++ if (retval) {
++ com_err(__func__, retval, "while reading inode %u", ino);
++ return retval;
++ }
++
++ retval = ext2fs_link(current_fs, parent_ino, name, ino, inode.i_flags);
++ if (retval == EXT2_ET_DIR_NO_SPACE) {
++ retval = ext2fs_expand_dir(current_fs, parent_ino);
++ if (retval) {
++ com_err(__func__, retval, "while expanding directory");
++ return retval;
++ }
++ retval = ext2fs_link(current_fs, parent_ino, name, ino, inode.i_flags);
++ }
++ if (retval) {
++ com_err(__func__, retval, "while linking %s", name);
++ return retval;
++ }
++
++ inode.i_links_count++;
++
++ retval = ext2fs_write_inode(current_fs, ino, &inode);
++ if (retval)
++ com_err(__func__, retval, "while writing inode %u", ino);
++
++ return retval;
++}
++
+ /* Fill the uid, gid, mode and time for the inode */
+ static void fill_inode(struct ext2_inode *inode, struct stat *st)
+ {
+@@ -278,6 +316,17 @@ fail:
+ return retval;
+ }
+
++int is_hardlink(ext2_ino_t ino)
++{
++ int i;
++
++ for(i = 0; i < hdlinks.count; i++) {
++ if(hdlinks.hdl[i].src_ino == ino)
++ return i;
++ }
++ return -1;
++}
++
+ /* Copy the native file to the fs */
+ errcode_t do_write_internal(ext2_ino_t cwd, const char *src, const char *dest)
+ {
+@@ -388,9 +437,11 @@ errcode_t populate_fs(ext2_ino_t parent_ino, const char *source_dir)
+ struct dirent *dent;
+ struct stat st;
+ char ln_target[PATH_MAX];
++ unsigned int save_inode;
+ ext2_ino_t ino;
+ errcode_t retval;
+ int read_cnt;
++ int hdlink;
+
+ root = EXT2_ROOT_INO;
+
+@@ -412,6 +463,22 @@ errcode_t populate_fs(ext2_ino_t parent_ino, const char *source_dir)
+ lstat(dent->d_name, &st);
+ name = dent->d_name;
+
++ /* Check for hardlinks */
++ save_inode = 0;
++ if (!S_ISDIR(st.st_mode) && !S_ISLNK(st.st_mode) && st.st_nlink > 1) {
++ hdlink = is_hardlink(st.st_ino);
++ if (hdlink >= 0) {
++ retval = add_link(parent_ino,
++ hdlinks.hdl[hdlink].dst_ino, name);
++ if (retval) {
++ com_err(__func__, retval, "while linking %s", name);
++ return retval;
++ }
++ continue;
++ } else
++ save_inode = 1;
++ }
++
+ switch(st.st_mode & S_IFMT) {
+ case S_IFCHR:
+ case S_IFBLK:
+@@ -480,6 +547,27 @@ errcode_t populate_fs(ext2_ino_t parent_ino, const char *source_dir)
+ _("while setting inode for \"%s\""), name);
+ return retval;
+ }
++
++ /* Save the hardlink ino */
++ if (save_inode) {
++ /*
++ * Check whether need more memory, and we don't need
++ * free() since the lifespan will be over after the fs
++ * populated.
++ */
++ if (hdlinks.count == hdlink_cnt) {
++ if ((hdlinks.hdl = realloc (hdlinks.hdl,
++ (hdlink_cnt + HDLINK_CNT) *
++ sizeof (struct hdlink_s))) == NULL) {
++ com_err(name, errno, "Not enough memory");
++ return errno;
++ }
++ hdlink_cnt += HDLINK_CNT;
++ }
++ hdlinks.hdl[hdlinks.count].src_ino = st.st_ino;
++ hdlinks.hdl[hdlinks.count].dst_ino = ino;
++ hdlinks.count++;
++ }
+ }
+ closedir(dh);
+ return retval;
+diff --git a/misc/create_inode.h b/misc/create_inode.h
+index 9fc97fa..2b6d429 100644
+--- a/misc/create_inode.h
++++ b/misc/create_inode.h
+@@ -6,9 +6,27 @@
+ #include "ext2fs/ext2fs.h"
+ #include "nls-enable.h"
+
++struct hdlink_s
++{
++ ext2_ino_t src_ino;
++ ext2_ino_t dst_ino;
++};
++
++struct hdlinks_s
++{
++ int count;
++ struct hdlink_s *hdl;
++};
++
++struct hdlinks_s hdlinks;
++
+ ext2_filsys current_fs;
+ ext2_ino_t root;
+
++/* For saving the hard links */
++#define HDLINK_CNT 4
++extern int hdlink_cnt;
++
+ /* For populating the filesystem */
+ extern errcode_t populate_fs(ext2_ino_t parent_ino, const char *source_dir);
+ extern errcode_t do_mknod_internal(ext2_ino_t cwd, const char *name, struct stat *st);
+diff --git a/misc/mke2fs.c b/misc/mke2fs.c
+index 578b62d..a63f0b7 100644
+--- a/misc/mke2fs.c
++++ b/misc/mke2fs.c
+@@ -2730,6 +2730,18 @@ no_journal:
+ if (!quiet)
+ printf("%s", _("Copying files into the device: "));
+
++ /*
++ * Allocate memory for the hardlinks, we don't need free()
++ * since the lifespan will be over after the fs populated.
++ */
++ if ((hdlinks.hdl = (struct hdlink_s *)
++ malloc(hdlink_cnt * sizeof(struct hdlink_s))) == NULL) {
++ fprintf(stderr, "%s", _("\nNot enough memory\n"));
++ retval = ext2fs_close(fs);
++ return retval;
++ }
++
++ hdlinks.count = 0;
+ current_fs = fs;
+ root = EXT2_ROOT_INO;
+ retval = populate_fs(root, root_dir);
+--
+1.7.10.4
+
