From a2ce25482a60e516d1d9b417ed666dac6fdebb93 Mon Sep 17 00:00:00 2001 From: Hallvard Furuseth Date: Mon, 20 May 2013 23:12:52 +0200 Subject: [PATCH] ITS#7515 Fix nested txn touch of subpage/ovpage. mdb_page_touch(): Don't touch a subpage, replacing with non-subpage. mdb_cursor_put(): Don't overwrite ancestor txn's dirty overflow page. --- libraries/liblmdb/mdb.c | 30 ++++++++++++++++++++++++++---- 1 file changed, 26 insertions(+), 4 deletions(-) diff --git a/libraries/liblmdb/mdb.c b/libraries/liblmdb/mdb.c index 6c7d28c6b9..acf8338ab3 100644 --- a/libraries/liblmdb/mdb.c +++ b/libraries/liblmdb/mdb.c @@ -1633,7 +1633,7 @@ finish: SETPGNO(NODEPTR(mc->mc_pg[mc->mc_top-1], mc->mc_ki[mc->mc_top-1]), mp->mp_pgno); else mc->mc_db->md_root = mp->mp_pgno; - } else if (mc->mc_txn->mt_parent) { + } else if (mc->mc_txn->mt_parent && !(mp->mp_flags & P_SUBP)) { MDB_page *np; MDB_ID2 mid; /* If txn has a parent, make sure the page is in our @@ -5197,11 +5197,11 @@ current: if (F_ISSET(leaf->mn_flags, F_BIGDATA)) { MDB_page *omp; pgno_t pg; - int ovpages, dpages; + unsigned psize = mc->mc_txn->mt_env->me_psize; + int level, ovpages, dpages = OVPAGES(data->mv_size, psize); - dpages = OVPAGES(data->mv_size, mc->mc_txn->mt_env->me_psize); memcpy(&pg, NODEDATA(leaf), sizeof(pg)); - if ((rc2 = mdb_page_get(mc->mc_txn, pg, &omp, NULL)) != 0) + if ((rc2 = mdb_page_get(mc->mc_txn, pg, &omp, &level)) != 0) return rc2; ovpages = omp->mp_pages; @@ -5211,6 +5211,28 @@ current: * bother to try shrinking the page if the new data * is smaller than the overflow threshold. */ + if (level > 1) { + /* It is writable only in a parent txn */ + size_t sz = (size_t) psize * ovpages, off; + MDB_page *np = mdb_page_malloc(mc, ovpages); + MDB_ID2 id2; + if (!np) + return ENOMEM; + id2.mid = pg; + id2.mptr = np; + mdb_mid2l_insert(mc->mc_txn->mt_u.dirty_list, &id2); + if (!(flags & MDB_RESERVE)) { + /* Copy end of page, adjusting alignment so + * compiler may copy words instead of bytes. + */ + off = (PAGEHDRSZ + data->mv_size) & -sizeof(size_t); + memcpy((size_t *)((char *)np + off), + (size_t *)((char *)omp + off), sz - off); + sz = PAGEHDRSZ; + } + memcpy(np, omp, sz); /* Copy beginning of page */ + omp = np; + } SETDSZ(leaf, data->mv_size); if (F_ISSET(flags, MDB_RESERVE)) data->mv_data = METADATA(omp); -- 2.39.5