forked from Mirrors/btrfs-progs
599a0abed5
Use an easier method to calculate the estimate device size for mkfs.btrfs --rootdir. The new method will over-estimate, but should ensure we won't encounter ENOSPC. It relies on the following data: 1) number of inodes -- for metadata chunk size 2) rounded up data size of each regular inode -- for data chunk size Total meta chunk size = round_up(nr_inode * (PATH_MAX * 3 + sectorsize), min_chunk_size) * profile_multiplier PATH_MAX is the maximum size possible for INODE_REF/DIR_INDEX/DIR_ITEM. Sectorsize is the maximum size possible for inline extent. min_chunk_size is 8M for SINGLE, and 32M for DUP, get from btrfs_alloc_chunk(). profile_multiplier is 1 for Single, 2 for DUP. Total data chunk size is much easier. Total data chunk size = round_up(total_data_usage, min_chunk_size) * profile_multiplier Total_data_usage is the sum of *rounded up* size of each regular inode use. min_chunk_size is 8M for SINGLE, 64M for DUP, get from btrfS_alloc_chunk(). Same profile_multiplier for meta. This over-estimate calculate is, of course inacurrate, but since we will later shrink the fs to its real usage, it doesn't matter much now. Signed-off-by: Qu Wenruo <wqu@suse.com> [ update comments ] Signed-off-by: David Sterba <dsterba@suse.com> |
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| .. | ||
| common.c | ||
| common.h | ||
| main.c | ||
| rootdir.c | ||
| rootdir.h | ||