diff options
| -rw-r--r-- | lib/compress.c | 25 |
1 files changed, 18 insertions, 7 deletions
diff --git a/lib/compress.c b/lib/compress.c index 81f277a..f6dc12a 100644 --- a/lib/compress.c +++ b/lib/compress.c @@ -170,6 +170,7 @@ static int z_erofs_compress_dedupe(struct z_erofs_vle_compress_ctx *ctx, unsigned int *len) { struct erofs_inode *inode = ctx->inode; + const unsigned int lclustermask = (1 << inode->z_logical_clusterbits) - 1; struct erofs_sb_info *sbi = inode->sbi; int ret = 0; @@ -205,22 +206,32 @@ static int z_erofs_compress_dedupe(struct z_erofs_vle_compress_ctx *ctx, * decompresssion could be done as another try in practice. */ if (dctx.e.compressedblks > 1 && - (ctx->clusterofs + ctx->e.length - delta) % erofs_blksiz(sbi) + - dctx.e.length < 2 * erofs_blksiz(sbi)) + ((ctx->clusterofs + ctx->e.length - delta) & lclustermask) + + dctx.e.length < 2 * (lclustermask + 1)) break; - /* fall back to noncompact indexes for deduplication */ - inode->z_advise &= ~Z_EROFS_ADVISE_COMPACTED_2B; - inode->datalayout = EROFS_INODE_COMPRESSED_FULL; - erofs_sb_set_dedupe(sbi); - if (delta) { DBG_BUGON(delta < 0); DBG_BUGON(!ctx->e.length); + + /* + * For big pcluster dedupe, if we decide to shorten the + * previous big pcluster, make sure that the previous + * CBLKCNT is still kept. + */ + if (ctx->e.compressedblks > 1 && + (ctx->clusterofs & lclustermask) + ctx->e.length + - delta < 2 * (lclustermask + 1)) + break; ctx->e.partial = true; ctx->e.length -= delta; } + /* fall back to noncompact indexes for deduplication */ + inode->z_advise &= ~Z_EROFS_ADVISE_COMPACTED_2B; + inode->datalayout = EROFS_INODE_COMPRESSED_FULL; + erofs_sb_set_dedupe(sbi); + sbi->saved_by_deduplication += dctx.e.compressedblks * erofs_blksiz(sbi); erofs_dbg("Dedupe %u %scompressed data (delta %d) to %u of %u blocks", |