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Message-ID: <20140501231413.31890.59296.stgit@birch.djwong.org> Date: Thu, 01 May 2014 16:14:13 -0700 From: "Darrick J. Wong" <darrick.wong@...cle.com> To: tytso@....edu, darrick.wong@...cle.com Cc: linux-ext4@...r.kernel.org Subject: [PATCH 17/37] libext2fs: file IO routines should handle uninit blocks The file IO routines do not handle uninit blocks at all. The read method should check for the uninit flag and return a buffer of zeroes, and the write routine should convert unwritten extents. Signed-off-by: Darrick J. Wong <darrick.wong@...cle.com> --- lib/ext2fs/fileio.c | 24 ++++++++++++++++++++++-- 1 file changed, 22 insertions(+), 2 deletions(-) diff --git a/lib/ext2fs/fileio.c b/lib/ext2fs/fileio.c index 14eaed3..1e386f8 100644 --- a/lib/ext2fs/fileio.c +++ b/lib/ext2fs/fileio.c @@ -123,6 +123,8 @@ errcode_t ext2fs_file_flush(ext2_file_t file) { errcode_t retval; ext2_filsys fs; + int ret_flags; + blk64_t dontcare; EXT2_CHECK_MAGIC(file, EXT2_ET_MAGIC_EXT2_FILE); fs = file->fs; @@ -131,6 +133,22 @@ errcode_t ext2fs_file_flush(ext2_file_t file) !(file->flags & EXT2_FILE_BUF_DIRTY)) return 0; + /* Is this an uninit block? */ + if (file->physblock && file->inode.i_flags & EXT4_EXTENTS_FL) { + retval = ext2fs_bmap2(fs, file->ino, &file->inode, BMAP_BUFFER, + 0, file->blockno, &ret_flags, &dontcare); + if (retval) + return retval; + if (ret_flags & BMAP_RET_UNINIT) { + retval = ext2fs_bmap2(fs, file->ino, &file->inode, + BMAP_BUFFER, BMAP_SET, + file->blockno, 0, + &file->physblock); + if (retval) + return retval; + } + } + /* * OK, the physical block hasn't been allocated yet. * Allocate it. @@ -185,15 +203,17 @@ static errcode_t load_buffer(ext2_file_t file, int dontfill) { ext2_filsys fs = file->fs; errcode_t retval; + int ret_flags; if (!(file->flags & EXT2_FILE_BUF_VALID)) { retval = ext2fs_bmap2(fs, file->ino, &file->inode, - BMAP_BUFFER, 0, file->blockno, 0, + BMAP_BUFFER, 0, file->blockno, &ret_flags, &file->physblock); if (retval) return retval; if (!dontfill) { - if (file->physblock) { + if (file->physblock && + !(ret_flags & BMAP_RET_UNINIT)) { retval = io_channel_read_blk64(fs->io, file->physblock, 1, file->buf); -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
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