Commit a126f17f663c ("EXTLINUX: Initial XFS filesystem support") broke
the code that inserts the installation subdirectory into the Extended
Patch Area (EPA). The EPA entry is used to set the initial working
directory on boot.

This caused boot failures for users that chose an install directory
other than /boot/syslinux (technically, it failed for any path not in
'search_directories' in load_env32()) due to ldlinux.c32 failing to
load because the initial working directory was not set correctly.

Cc: Paulo Alcantara <pcacjr@zytor.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>

Due to delayed allocation feature on XFS filesystems, a write is not
guaranteed to flushed out to the underlying file system after crash or
something else - so we need to make sure that ldlinux.sys is installed
correctly in the mounted filesystem.

Signed-off-by: Paulo Alcantara <pcacjr@zytor.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>

Pull XFS filesystem driver from Paulo Alcantara,

* 'xfs-for-hpa' of git://zytor.com/users/pcacjr/syslinux: (60 commits)
  xfs: Fix the way we check di_mode of an inode
  xfs: Cleanup previous commit
  xfs: Add xfs_readlink()
  xfs: Cleanup and remove some trailing whitespaces
  xfs: Add XFS_DINODE_FMT_BTREE support in xfs_next_extent()
  xfs: Cleanup and remove some trailing whitespaces
  xfs: Rework xfs_dir2_get_right_blk()
  xfs: cleanup unused structure
  xfs: Remove some trailing whitespaces
  xfs: Add full B+tree search support in xfs_dir2_node_find_entry()
  xfs: Add xfs_fmt_btree_find_entry()
  xfs: Fix memory leak in xfs_dir2_node_find_entry() function
  xfs: Cleanup xfs_readdir_dir2_leaf() function
  xfs: Implement xfs_readdir_dir2_node() function
  EXTLINUX: Add sanity check for XFS filesystems
  xfs: Add xfs_fmt_local_readdir() function
  xfs: Add xfs_fmt_local_find_entry() function
  xfs: Move readdir functions to another source file
  xfs: Remove trailing whitespace in xfs_dir2_isleaf() function
  xfs: Move dir2 functions to another source file
  ...

Conflicts:
	extlinux/main.c

If opt.reset_adv is set the call to ext_read_adv() is skipped which
would have initialised 'filename'. This means that a pointer
containing random data from the stack is passed to ext_write_adv().

Just delete the opt.reset_adv logic since modify_adv() handles that
case anyway.

Reported-by: Frediano Ziglio <frediano.ziglio@citrix.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>

The following conflict is a result of the fact comapi_chainboot was
only stubbed out on the 'elflink' branch but was properly marked as
obsolete in 'master'.

Conflicts:
	core/comboot.inc

Just some minor cleanup

Signed-off-by: Frediano Ziglio <frediano.ziglio@citrix.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>

Because ldlinux.c32 is required for Syslinux to function correctly, we
should be installing it automatically much like ldlinux.sys.

Signed-off-by: Matt Fleming <matt.fleming@intel.com>

find_mount() may return NULL, so we'd really better check for that
*before* dereferencing the pointer.

Signed-off-by: Matt Fleming <matt.fleming@intel.com>

Syslinux won't work on >4 KiB filesystem block sizes since there is no
left space in MBR to determine where to install Syslinux bootsector.

If one is trying to install Syslinux in a XFS partition with a
filesystem block size different of 4 KiB, a proper error will be
returned to the user informing that the current filesystem block size
isn't supported by Syslinux.

Reported-by: Gene Cumm <gene.cumm@gmail.com>
Signed-off-by: Paulo Alcantara <pcacjr@zytor.com>

rewrite_boot_image() wraps the logic from previous
ext2_fat_install_file(). The deleted lines includes
the set_attributes(), while it is actually not
within the rewrite_boot_image().

We add set_attributes() and some helper judgement just
as what we do in xfs_install_file().

Signed-off-by: Chen Baozi <baozich@gmail.com>
Signed-off-by: Paulo Alcantara <pcacjr@zytor.com>