diff options
| -rw-r--r-- | fs/btrfs/compression.c | 40 |
1 files changed, 16 insertions, 24 deletions
diff --git a/fs/btrfs/compression.c b/fs/btrfs/compression.c index 7c1c018dbd6f..ad90e14032db 100644 --- a/fs/btrfs/compression.c +++ b/fs/btrfs/compression.c @@ -1489,10 +1489,8 @@ static void heuristic_collect_sample(struct inode *inode, u64 start, u64 end, struct heuristic_ws *ws) { const u32 blocksize = BTRFS_I(inode)->root->fs_info->sectorsize; - struct folio *folio; - u64 index, index_end; - u32 i, curr_sample_pos; - u8 *in_data; + u64 cur = start; + u32 curr_sample_pos = 0; ASSERT(IS_ALIGNED(start, blocksize) && IS_ALIGNED(end + 1, blocksize)); @@ -1508,33 +1506,27 @@ static void heuristic_collect_sample(struct inode *inode, u64 start, u64 end, if (end + 1 - start > BTRFS_MAX_UNCOMPRESSED) end = start + BTRFS_MAX_UNCOMPRESSED - 1; - index = start >> PAGE_SHIFT; - index_end = end >> PAGE_SHIFT; + while (cur < end) { + struct folio *folio; + void *in_data; + u64 next_pos; - curr_sample_pos = 0; - while (index <= index_end) { - folio = filemap_get_folio(inode->i_mapping, index); + folio = filemap_get_folio(inode->i_mapping, cur >> PAGE_SHIFT); + /* All folios inside the range should exist and be locked. */ ASSERT(!IS_ERR(folio)); - in_data = kmap_local_folio(folio, - offset_in_folio(folio, index << PAGE_SHIFT)); - /* Handle case where the start is not aligned to PAGE_SIZE */ - i = start % PAGE_SIZE; - while (i < PAGE_SIZE - SAMPLING_READ_SIZE) { - /* Don't sample any garbage from the last page */ - if (start > end + 1 - SAMPLING_READ_SIZE) - break; - memcpy(&ws->sample[curr_sample_pos], &in_data[i], - SAMPLING_READ_SIZE); - i += SAMPLING_INTERVAL; - start += SAMPLING_INTERVAL; + next_pos = min_t(u64, end + 1, folio_next_pos(folio)); + in_data = kmap_local_folio(folio, 0); + + for (; cur < next_pos; cur += SAMPLING_INTERVAL) { + memcpy(&ws->sample[curr_sample_pos], + in_data + offset_in_folio(folio, cur), + SAMPLING_READ_SIZE); curr_sample_pos += SAMPLING_READ_SIZE; } kunmap_local(in_data); folio_put(folio); - - index++; + cur = next_pos; } - ws->sample_size = curr_sample_pos; } |