From 7aeb72224120e0c49ba4c93d75f8f0d6a87f6afd Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Fri, 13 Dec 2013 11:00:43 +1100 Subject: [PATCH] xfs: refactor xfs_buf_item_format_segment Add two helpers to make the code more readable. Signed-off-by: Christoph Hellwig Reviewed-by: Dave Chinner Signed-off-by: Dave Chinner --- fs/xfs/xfs_buf_item.c | 72 ++++++++++++++++++++++++++++----------------------- 1 file changed, 39 insertions(+), 33 deletions(-) diff --git a/fs/xfs/xfs_buf_item.c b/fs/xfs/xfs_buf_item.c index a64f67b..a30c1fb 100644 --- a/fs/xfs/xfs_buf_item.c +++ b/fs/xfs/xfs_buf_item.c @@ -182,6 +182,34 @@ xfs_buf_item_size( trace_xfs_buf_item_size(bip); } +static inline struct xfs_log_iovec * +xfs_buf_item_copy_iovec( + struct xfs_log_iovec *vecp, + struct xfs_buf *bp, + uint offset, + int first_bit, + uint nbits) +{ + offset += first_bit * XFS_BLF_CHUNK; + + vecp->i_type = XLOG_REG_TYPE_BCHUNK; + vecp->i_addr = xfs_buf_offset(bp, offset); + vecp->i_len = nbits * XFS_BLF_CHUNK; + return vecp + 1; +} + +static inline bool +xfs_buf_item_straddle( + struct xfs_buf *bp, + uint offset, + int next_bit, + int last_bit) +{ + return xfs_buf_offset(bp, offset + (next_bit << XFS_BLF_SHIFT)) != + (xfs_buf_offset(bp, offset + (last_bit << XFS_BLF_SHIFT)) + + XFS_BLF_CHUNK); +} + static struct xfs_log_iovec * xfs_buf_item_format_segment( struct xfs_buf_log_item *bip, @@ -196,7 +224,6 @@ xfs_buf_item_format_segment( int last_bit; int next_bit; uint nbits; - uint buffer_offset; /* copy the flags across from the base format item */ blfp->blf_flags = bip->__bli_format.blf_flags; @@ -239,7 +266,6 @@ xfs_buf_item_format_segment( /* * Fill in an iovec for each set of contiguous chunks. */ - last_bit = first_bit; nbits = 1; for (;;) { @@ -252,42 +278,22 @@ xfs_buf_item_format_segment( next_bit = xfs_next_bit(blfp->blf_data_map, blfp->blf_map_size, (uint)last_bit + 1); /* - * If we run out of bits fill in the last iovec and get - * out of the loop. - * Else if we start a new set of bits then fill in the - * iovec for the series we were looking at and start - * counting the bits in the new one. - * Else we're still in the same set of bits so just - * keep counting and scanning. + * If we run out of bits fill in the last iovec and get out of + * the loop. Else if we start a new set of bits then fill in + * the iovec for the series we were looking at and start + * counting the bits in the new one. Else we're still in the + * same set of bits so just keep counting and scanning. */ if (next_bit == -1) { - buffer_offset = offset + first_bit * XFS_BLF_CHUNK; - vecp->i_addr = xfs_buf_offset(bp, buffer_offset); - vecp->i_len = nbits * XFS_BLF_CHUNK; - vecp->i_type = XLOG_REG_TYPE_BCHUNK; + xfs_buf_item_copy_iovec(vecp, bp, offset, + first_bit, nbits); nvecs++; break; - } else if (next_bit != last_bit + 1) { - buffer_offset = offset + first_bit * XFS_BLF_CHUNK; - vecp->i_addr = xfs_buf_offset(bp, buffer_offset); - vecp->i_len = nbits * XFS_BLF_CHUNK; - vecp->i_type = XLOG_REG_TYPE_BCHUNK; - nvecs++; - vecp++; - first_bit = next_bit; - last_bit = next_bit; - nbits = 1; - } else if (xfs_buf_offset(bp, offset + - (next_bit << XFS_BLF_SHIFT)) != - (xfs_buf_offset(bp, offset + - (last_bit << XFS_BLF_SHIFT)) + - XFS_BLF_CHUNK)) { - buffer_offset = offset + first_bit * XFS_BLF_CHUNK; - vecp->i_addr = xfs_buf_offset(bp, buffer_offset); - vecp->i_len = nbits * XFS_BLF_CHUNK; - vecp->i_type = XLOG_REG_TYPE_BCHUNK; + } else if (next_bit != last_bit + 1 || + xfs_buf_item_straddle(bp, offset, next_bit, last_bit)) { + vecp = xfs_buf_item_copy_iovec(vecp, bp, offset, + first_bit, nbits); nvecs++; - vecp++; first_bit = next_bit; last_bit = next_bit; nbits = 1; -- 2.7.4