[PATCH 1/3] erofs-utils: get rid of useless nr_dup

[Gao Xiang]

Also refine the longest detection.

Fixes: 990c7e383795 ("erofs-utils: mkfs: support fragment deduplication")
Signed-off-by: Gao Xiang <hsiang...@linux.alibaba.com>
---
 lib/fragments.c | 18 +++++++++---------
 1 file changed, 9 insertions(+), 9 deletions(-)

diff --git a/lib/fragments.c b/lib/fragments.c
index c67c1bb..1e41485 100644
--- a/lib/fragments.c
+++ b/lib/fragments.c
@@ -26,7 +26,7 @@
 
 struct erofs_fragment_dedupe_item {
        struct list_head        list;
-       unsigned int            length, nr_dup;
+       unsigned int            length;
        erofs_off_t             pos;
        u8                      data[];
 };
@@ -53,7 +53,7 @@ static int z_erofs_fragments_dedupe_find(struct erofs_inode 
*inode, int fd,
        struct erofs_fragment_dedupe_item *cur, *di = NULL;
        struct list_head *head;
        u8 *data;
-       unsigned int length, e2;
+       unsigned int length, e2, deduped;
        int ret;
 
        head = &dupli_frags[FRAGMENT_HASH(crc)];
@@ -83,6 +83,7 @@ static int z_erofs_fragments_dedupe_find(struct erofs_inode 
*inode, int fd,
 
        DBG_BUGON(length <= EROFS_TOF_HASHLEN);
        e2 = length - EROFS_TOF_HASHLEN;
+       deduped = 0;
 
        list_for_each_entry(cur, head, list) {
                unsigned int e1, mn, i = 0;
@@ -97,22 +98,22 @@ static int z_erofs_fragments_dedupe_find(struct erofs_inode 
*inode, int fd,
                while (i < mn && cur->data[e1 - i - 1] == data[e2 - i - 1])
                        ++i;
 
-               if (i && (!di || i + EROFS_TOF_HASHLEN > di->nr_dup)) {
-                       cur->nr_dup = i + EROFS_TOF_HASHLEN;
+               if (!di || i + EROFS_TOF_HASHLEN > deduped) {
+                       deduped = i + EROFS_TOF_HASHLEN;
                        di = cur;
 
                        /* full match */
-                       if (i == mn)
+                       if (i == e2)
                                break;
                }
        }
        if (!di)
                goto out;
 
-       DBG_BUGON(di->length < di->nr_dup);
+       DBG_BUGON(di->length < deduped);
 
-       inode->fragment_size = di->nr_dup;
-       inode->fragmentoff = di->pos + di->length - di->nr_dup;
+       inode->fragment_size = deduped;
+       inode->fragmentoff = di->pos + di->length - deduped;
 
        erofs_dbg("Dedupe %u tail data at %llu", inode->fragment_size,
                  inode->fragmentoff | 0ULL);
@@ -161,7 +162,6 @@ static int z_erofs_fragments_dedupe_insert(void *data, 
unsigned int len,
        memcpy(di->data, data, len);
        di->length = len;
        di->pos = pos;
-       di->nr_dup = 0;
 
        list_add_tail(&di->list, &dupli_frags[FRAGMENT_HASH(crc)]);
        return 0;
-- 
2.36.1