From ef97d608c7f069331d8141d1d59df715f4a3beaf Mon Sep 17 00:00:00 2001 From: Alberto Garcia Date: Sat, 18 Jan 2020 20:09:26 +0100 Subject: [PATCH] qcow2: Don't round the L1 table allocation up to the sector size The L1 table is read from disk using the byte-based bdrv_pread() and is never accessed beyond its last element, so there's no need to allocate more memory than that. Signed-off-by: Alberto Garcia Reviewed-by: Max Reitz Message-id: b2e27214ec7b03a585931bcf383ee1ac3a641a10.1579374329.git.berto@igalia.com Signed-off-by: Max Reitz --- block/qcow2-cluster.c | 5 ++--- block/qcow2-refcount.c | 2 +- block/qcow2-snapshot.c | 3 +-- block/qcow2.c | 2 +- 4 files changed, 5 insertions(+), 7 deletions(-) diff --git a/block/qcow2-cluster.c b/block/qcow2-cluster.c index e9431f6785..0384fb2339 100644 --- a/block/qcow2-cluster.c +++ b/block/qcow2-cluster.c @@ -124,12 +124,11 @@ int qcow2_grow_l1_table(BlockDriverState *bs, uint64_t min_size, #endif new_l1_size2 = sizeof(uint64_t) * new_l1_size; - new_l1_table = qemu_try_blockalign(bs->file->bs, - ROUND_UP(new_l1_size2, 512)); + new_l1_table = qemu_try_blockalign(bs->file->bs, new_l1_size2); if (new_l1_table == NULL) { return -ENOMEM; } - memset(new_l1_table, 0, ROUND_UP(new_l1_size2, 512)); + memset(new_l1_table, 0, new_l1_size2); if (s->l1_size) { memcpy(new_l1_table, s->l1_table, s->l1_size * sizeof(uint64_t)); diff --git a/block/qcow2-refcount.c b/block/qcow2-refcount.c index f67ac6b2d8..c963bc8de1 100644 --- a/block/qcow2-refcount.c +++ b/block/qcow2-refcount.c @@ -1262,7 +1262,7 @@ int qcow2_update_snapshot_refcount(BlockDriverState *bs, * l1_table_offset when it is the current s->l1_table_offset! Be careful * when changing this! */ if (l1_table_offset != s->l1_table_offset) { - l1_table = g_try_malloc0(ROUND_UP(l1_size2, 512)); + l1_table = g_try_malloc0(l1_size2); if (l1_size2 && l1_table == NULL) { ret = -ENOMEM; goto fail; diff --git a/block/qcow2-snapshot.c b/block/qcow2-snapshot.c index 5ab64da1ec..82c32d4c9b 100644 --- a/block/qcow2-snapshot.c +++ b/block/qcow2-snapshot.c @@ -1024,8 +1024,7 @@ int qcow2_snapshot_load_tmp(BlockDriverState *bs, return ret; } new_l1_bytes = sn->l1_size * sizeof(uint64_t); - new_l1_table = qemu_try_blockalign(bs->file->bs, - ROUND_UP(new_l1_bytes, 512)); + new_l1_table = qemu_try_blockalign(bs->file->bs, new_l1_bytes); if (new_l1_table == NULL) { return -ENOMEM; } diff --git a/block/qcow2.c b/block/qcow2.c index e29fc07068..83db013814 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -1491,7 +1491,7 @@ static int coroutine_fn qcow2_do_open(BlockDriverState *bs, QDict *options, if (s->l1_size > 0) { s->l1_table = qemu_try_blockalign(bs->file->bs, - ROUND_UP(s->l1_size * sizeof(uint64_t), 512)); + s->l1_size * sizeof(uint64_t)); if (s->l1_table == NULL) { error_setg(errp, "Could not allocate L1 table"); ret = -ENOMEM;