[PATCH v2] erofs-utils: no compression case for tail-end block in vle_write_indexes()

Yue Hu zbestahu at gmail.com
Fri Jul 23 16:27:39 AEST 2021


From: Yue Hu <huyue2 at yulong.com>

Note that count value will be always greater than EROFS_BLKSIZ when
calling erofs_compress_destsize() in vle_compress_one(). So, the d1
always >= 1 for compressed block in vle_write_indexes(). That is to
say tail-end block can't be compressed.

Signed-off-by: Yue Hu <huyue2 at yulong.com>
---
v2: add DBG_BUGON(!raw), a TODO comment.

 lib/compress.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/lib/compress.c b/lib/compress.c
index af0c720..40723a1 100644
--- a/lib/compress.c
+++ b/lib/compress.c
@@ -73,10 +73,11 @@ static void vle_write_indexes(struct z_erofs_vle_compress_ctx *ctx,
 
 	di.di_clusterofs = cpu_to_le16(ctx->clusterofs);
 
-	/* whether the tail-end (un)compressed block or not */
+	/* whether the tail-end uncompressed block or not */
 	if (!d1) {
-		type = raw ? Z_EROFS_VLE_CLUSTER_TYPE_PLAIN :
-			Z_EROFS_VLE_CLUSTER_TYPE_HEAD;
+		/* TODO: tail-packing inline compressed data */
+		DBG_BUGON(!raw);
+		type = Z_EROFS_VLE_CLUSTER_TYPE_PLAIN;
 		advise = cpu_to_le16(type << Z_EROFS_VLE_DI_CLUSTER_TYPE_BIT);
 
 		di.di_advise = advise;
-- 
1.9.1



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