From d63d61c16972c667d770f713c21aa04e2c0489d2 Mon Sep 17 00:00:00 2001 From: Richard Weinberger Date: Wed, 19 Oct 2016 15:59:12 +0200 Subject: [PATCH] ubifs: Implement UBIFS_FLG_DOUBLE_HASH This feature flag indicates that all directory entry nodes have a 32bit cookie set and therefore UBIFS is allowed to perform lookups by hash. Signed-off-by: Richard Weinberger --- fs/ubifs/journal.c | 14 +++++++++++--- fs/ubifs/sb.c | 2 ++ fs/ubifs/tnc.c | 3 +++ fs/ubifs/ubifs-media.h | 3 +++ fs/ubifs/ubifs.h | 2 ++ 5 files changed, 21 insertions(+), 3 deletions(-) diff --git a/fs/ubifs/journal.c b/fs/ubifs/journal.c index 88d33775f18b..a459211a1c21 100644 --- a/fs/ubifs/journal.c +++ b/fs/ubifs/journal.c @@ -501,6 +501,14 @@ static void mark_inode_clean(struct ubifs_info *c, struct ubifs_inode *ui) ui->dirty = 0; } +static void set_dent_cookie(struct ubifs_info *c, struct ubifs_dent_node *dent) +{ + if (c->double_hash) + dent->cookie = prandom_u32(); + else + dent->cookie = 0; +} + /** * ubifs_jnl_update - update inode. * @c: UBIFS file-system description object @@ -589,7 +597,7 @@ int ubifs_jnl_update(struct ubifs_info *c, const struct inode *dir, dent->nlen = cpu_to_le16(fname_len(nm)); memcpy(dent->name, fname_name(nm), fname_len(nm)); dent->name[fname_len(nm)] = '\0'; - dent->cookie = prandom_u32(); + set_dent_cookie(c, dent); zero_dent_node_unused(dent); ubifs_prep_grp_node(c, dent, dlen, 0); @@ -1125,7 +1133,7 @@ int ubifs_jnl_rename(struct ubifs_info *c, const struct inode *old_dir, dent->nlen = cpu_to_le16(fname_len(new_nm)); memcpy(dent->name, fname_name(new_nm), fname_len(new_nm)); dent->name[fname_len(new_nm)] = '\0'; - dent->cookie = prandom_u32(); + set_dent_cookie(c, dent); zero_dent_node_unused(dent); ubifs_prep_grp_node(c, dent, dlen1, 0); @@ -1144,7 +1152,7 @@ int ubifs_jnl_rename(struct ubifs_info *c, const struct inode *old_dir, dent2->nlen = cpu_to_le16(fname_len(old_nm)); memcpy(dent2->name, fname_name(old_nm), fname_len(old_nm)); dent2->name[fname_len(old_nm)] = '\0'; - dent2->cookie = prandom_u32(); + set_dent_cookie(c, dent2); zero_dent_node_unused(dent2); ubifs_prep_grp_node(c, dent2, dlen2, 0); diff --git a/fs/ubifs/sb.c b/fs/ubifs/sb.c index 3cbb904a6d7d..4a2b4c361587 100644 --- a/fs/ubifs/sb.c +++ b/fs/ubifs/sb.c @@ -163,6 +163,7 @@ static int create_default_filesystem(struct ubifs_info *c) tmp64 = (long long)max_buds * c->leb_size; if (big_lpt) sup_flags |= UBIFS_FLG_BIGLPT; + sup_flags |= UBIFS_FLG_DOUBLE_HASH; sup->ch.node_type = UBIFS_SB_NODE; sup->key_hash = UBIFS_KEY_HASH_R5; @@ -620,6 +621,7 @@ int ubifs_read_superblock(struct ubifs_info *c) memcpy(&c->uuid, &sup->uuid, 16); c->big_lpt = !!(sup_flags & UBIFS_FLG_BIGLPT); c->space_fixup = !!(sup_flags & UBIFS_FLG_SPACE_FIXUP); + c->double_hash = !!(sup_flags & UBIFS_FLG_DOUBLE_HASH); /* Automatically increase file system size to the maximum size */ c->old_leb_cnt = c->leb_cnt; diff --git a/fs/ubifs/tnc.c b/fs/ubifs/tnc.c index 1bba4c8b5d3d..74ae2de949df 100644 --- a/fs/ubifs/tnc.c +++ b/fs/ubifs/tnc.c @@ -1930,6 +1930,9 @@ int ubifs_tnc_lookup_dh(struct ubifs_info *c, const union ubifs_key *key, int err; const struct ubifs_dent_node *dent = node; + if (!c->double_hash) + return -EOPNOTSUPP; + /* * We assume that in most of the cases there are no name collisions and * 'ubifs_tnc_lookup()' returns us the right direntry. diff --git a/fs/ubifs/ubifs-media.h b/fs/ubifs/ubifs-media.h index 249124d9a801..0cbdc6b70a00 100644 --- a/fs/ubifs/ubifs-media.h +++ b/fs/ubifs/ubifs-media.h @@ -418,10 +418,13 @@ enum { * * UBIFS_FLG_BIGLPT: if "big" LPT model is used if set * UBIFS_FLG_SPACE_FIXUP: first-mount "fixup" of free space within LEBs needed + * UBIFS_FLG_DOUBLE_HASH: store a 32bit cookie in directory entry nodes to + * support 64bit cookies for lookups by hash */ enum { UBIFS_FLG_BIGLPT = 0x02, UBIFS_FLG_SPACE_FIXUP = 0x04, + UBIFS_FLG_DOUBLE_HASH = 0x08, }; /** diff --git a/fs/ubifs/ubifs.h b/fs/ubifs/ubifs.h index 9be71b6a4cd2..5089663c0d1b 100644 --- a/fs/ubifs/ubifs.h +++ b/fs/ubifs/ubifs.h @@ -1006,6 +1006,7 @@ struct ubifs_debug_info; * * @big_lpt: flag that LPT is too big to write whole during commit * @space_fixup: flag indicating that free space in LEBs needs to be cleaned up + * @double_hash: flag indicating that we can do lookups by hash * @no_chk_data_crc: do not check CRCs when reading data nodes (except during * recovery) * @bulk_read: enable bulk-reads @@ -1248,6 +1249,7 @@ struct ubifs_info { unsigned int big_lpt:1; unsigned int space_fixup:1; + unsigned int double_hash:1; unsigned int no_chk_data_crc:1; unsigned int bulk_read:1; unsigned int default_compr:2; -- GitLab