diff options
Diffstat (limited to 'fs/xfs/xfs_buf_item.c')
| -rw-r--r-- | fs/xfs/xfs_buf_item.c | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/fs/xfs/xfs_buf_item.c b/fs/xfs/xfs_buf_item.c index 19eb0b7a3e58..90139e0f3271 100644 --- a/fs/xfs/xfs_buf_item.c +++ b/fs/xfs/xfs_buf_item.c @@ -104,6 +104,25 @@ xfs_buf_item_size_segment( } /* + * Compute the worst case log item overhead for an invalidated buffer with the + * given map count and block size. + */ +unsigned int +xfs_buf_inval_log_space( + unsigned int map_count, + unsigned int blocksize) +{ + unsigned int chunks = DIV_ROUND_UP(blocksize, XFS_BLF_CHUNK); + unsigned int bitmap_size = DIV_ROUND_UP(chunks, NBWORD); + unsigned int ret = + offsetof(struct xfs_buf_log_format, blf_data_map) + + (bitmap_size * sizeof_field(struct xfs_buf_log_format, + blf_data_map[0])); + + return ret * map_count; +} + +/* * Return the number of log iovecs and space needed to log the given buf log * item. * |