From 9026b3db3af838983ed81aad2b4d5e09df1013e3 Mon Sep 17 00:00:00 2001 From: "Darrick J. Wong" Date: Fri, 30 Sep 2011 12:41:26 -0700 Subject: libext2fs: Always swab the MMP block on big-endian systems machines The MMP code in libext2fs tries to gate MMP block swab'ing with this test: if (fs->super->s_magic == ext2fs_swab16(EXT2_SUPER_MAGIC)) However, EXT2FS_ENABLE_SWAPFS never seems to be defined anywhere (all possible existed, the field fs->super->s_magic is always in host byteorder, so the test always fails. So, we can change the #ifdef to WORDS_BIGENDIAN (which is conditionally defined on BE platforms) and get rid of the broken if test. Signed-off-by: Darrick J. Wong Signed-off-by: "Theodore Ts'o" --- lib/ext2fs/mmp.c | 15 ++++++--------- 1 file changed, 6 insertions(+), 9 deletions(-) diff --git a/lib/ext2fs/mmp.c b/lib/ext2fs/mmp.c index ed6ee425..91f4fb28 100644 --- a/lib/ext2fs/mmp.c +++ b/lib/ext2fs/mmp.c @@ -91,9 +91,8 @@ errcode_t ext2fs_mmp_read(ext2_filsys fs, blk64_t mmp_blk, void *buf) } mmp_cmp = fs->mmp_cmp; -#ifdef EXT2FS_ENABLE_SWAPFS - if (fs->flags & EXT2_FLAG_SWAP_BYTES) - ext2fs_swap_mmp(mmp_cmp); +#ifdef WORDS_BIGENDIAN + ext2fs_swap_mmp(mmp_cmp); #endif if (buf != NULL && buf != fs->mmp_cmp) @@ -122,18 +121,16 @@ errcode_t ext2fs_mmp_write(ext2_filsys fs, blk64_t mmp_blk, void *buf) fs->super->s_mmp_block > ext2fs_blocks_count(fs->super)) return EXT2_ET_MMP_BAD_BLOCK; -#ifdef EXT2FS_ENABLE_SWAPFS - if (fs->super->s_magic == ext2fs_swab16(EXT2_SUPER_MAGIC)) - ext2fs_swap_mmp(mmp_s); +#ifdef WORDS_BIGENDIAN + ext2fs_swap_mmp(mmp_s); #endif /* I was tempted to make this use O_DIRECT and the mmp_fd, but * this caused no end of grief, while leaving it as-is works. */ retval = io_channel_write_blk64(fs->io, mmp_blk, -fs->blocksize, buf); -#ifdef EXT2FS_ENABLE_SWAPFS - if (fs->super->s_magic == ext2fs_swab16(EXT2_SUPER_MAGIC)) - ext2fs_swap_mmp(mmp_s); +#ifdef WORDS_BIGENDIAN + ext2fs_swap_mmp(mmp_s); #endif /* Make sure the block gets to disk quickly */ -- cgit v1.2.3