diff options
| -rw-r--r-- | fs/erofs/zdata.c | 51 |
1 files changed, 24 insertions, 27 deletions
diff --git a/fs/erofs/zdata.c b/fs/erofs/zdata.c index 37fee144f0e7..777790038bc9 100644 --- a/fs/erofs/zdata.c +++ b/fs/erofs/zdata.c @@ -292,34 +292,33 @@ static int z_erofs_attach_page(struct z_erofs_collector *clt, return ret ? 0 : -EAGAIN; } -static enum z_erofs_collectmode -try_to_claim_pcluster(struct z_erofs_pcluster *pcl, - z_erofs_next_pcluster_t *owned_head) +static void z_erofs_try_to_claim_pcluster(struct z_erofs_collector *clt) { - /* let's claim these following types of pclusters */ -retry: - if (pcl->next == Z_EROFS_PCLUSTER_NIL) { - /* type 1, nil pcluster */ - if (cmpxchg(&pcl->next, Z_EROFS_PCLUSTER_NIL, - *owned_head) != Z_EROFS_PCLUSTER_NIL) - goto retry; + struct z_erofs_pcluster *pcl = clt->pcl; + z_erofs_next_pcluster_t *owned_head = &clt->owned_head; + /* type 1, nil pcluster (this pcluster doesn't belong to any chain.) */ + if (cmpxchg(&pcl->next, Z_EROFS_PCLUSTER_NIL, + *owned_head) == Z_EROFS_PCLUSTER_NIL) { *owned_head = &pcl->next; - /* lucky, I am the followee :) */ - return COLLECT_PRIMARY_FOLLOWED; - } else if (pcl->next == Z_EROFS_PCLUSTER_TAIL) { - /* - * type 2, link to the end of a existing open chain, - * be careful that its submission itself is governed - * by the original owned chain. - */ - if (cmpxchg(&pcl->next, Z_EROFS_PCLUSTER_TAIL, - *owned_head) != Z_EROFS_PCLUSTER_TAIL) - goto retry; + /* so we can attach this pcluster to our submission chain. */ + clt->mode = COLLECT_PRIMARY_FOLLOWED; + return; + } + + /* + * type 2, link to the end of an existing open chain, be careful + * that its submission is controlled by the original attached chain. + */ + if (cmpxchg(&pcl->next, Z_EROFS_PCLUSTER_TAIL, + *owned_head) == Z_EROFS_PCLUSTER_TAIL) { *owned_head = Z_EROFS_PCLUSTER_TAIL; - return COLLECT_PRIMARY_HOOKED; + clt->mode = COLLECT_PRIMARY_HOOKED; + clt->tailpcl = NULL; + return; } - return COLLECT_PRIMARY; /* :( better luck next time */ + /* type 3, it belongs to a chain, but it isn't the end of the chain */ + clt->mode = COLLECT_PRIMARY; } static int z_erofs_lookup_collection(struct z_erofs_collector *clt, @@ -364,10 +363,8 @@ static int z_erofs_lookup_collection(struct z_erofs_collector *clt, /* used to check tail merging loop due to corrupted images */ if (clt->owned_head == Z_EROFS_PCLUSTER_TAIL) clt->tailpcl = pcl; - clt->mode = try_to_claim_pcluster(pcl, &clt->owned_head); - /* clean tailpcl if the current owned_head is Z_EROFS_PCLUSTER_TAIL */ - if (clt->owned_head == Z_EROFS_PCLUSTER_TAIL) - clt->tailpcl = NULL; + + z_erofs_try_to_claim_pcluster(clt); clt->cl = cl; return 0; } |