xfs: clean up xfs_mount allocation and dynamic initializers

Most of the generic data structures embedded in xfs_mount are
dynamically initialized immediately after mp is allocated. A few
fields are left out and initialized during the xfs_mountfs()
sequence, after mp has been attached to the superblock.

To clean this up and help prevent premature access of associated
fields, refactor xfs_mount allocation and all dependent init calls
into a new helper. This self-documents that all low level data
structures (i.e., locks, trees, etc.) should be initialized before
xfs_mount is attached to the superblock.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
This commit is contained in:
Brian Foster 2018-03-23 17:54:32 -07:00 committed by Darrick J. Wong
parent fa4493f0d9
commit 72c44e35f0
3 changed files with 30 additions and 14 deletions

View file

@ -731,7 +731,6 @@ xfs_sb_mount_common(
struct xfs_sb *sbp)
{
mp->m_agfrotor = mp->m_agirotor = 0;
spin_lock_init(&mp->m_agirotor_lock);
mp->m_maxagi = mp->m_sb.sb_agcount;
mp->m_blkbit_log = sbp->sb_blocklog + XFS_NBBYLOG;
mp->m_blkbb_log = sbp->sb_blocklog - BBSHIFT;

View file

@ -817,8 +817,6 @@ xfs_mountfs(
/*
* Allocate and initialize the per-ag data.
*/
spin_lock_init(&mp->m_perag_lock);
INIT_RADIX_TREE(&mp->m_perag_tree, GFP_ATOMIC);
error = xfs_initialize_perag(mp, sbp->sb_agcount, &mp->m_maxagi);
if (error) {
xfs_warn(mp, "Failed per-ag init: %d", error);

View file

@ -1579,6 +1579,31 @@ xfs_destroy_percpu_counters(
percpu_counter_destroy(&mp->m_fdblocks);
}
static struct xfs_mount *
xfs_mount_alloc(
struct super_block *sb)
{
struct xfs_mount *mp;
mp = kzalloc(sizeof(struct xfs_mount), GFP_KERNEL);
if (!mp)
return NULL;
mp->m_super = sb;
spin_lock_init(&mp->m_sb_lock);
spin_lock_init(&mp->m_agirotor_lock);
INIT_RADIX_TREE(&mp->m_perag_tree, GFP_ATOMIC);
spin_lock_init(&mp->m_perag_lock);
mutex_init(&mp->m_growlock);
atomic_set(&mp->m_active_trans, 0);
INIT_DELAYED_WORK(&mp->m_reclaim_work, xfs_reclaim_worker);
INIT_DELAYED_WORK(&mp->m_eofblocks_work, xfs_eofblocks_worker);
INIT_DELAYED_WORK(&mp->m_cowblocks_work, xfs_cowblocks_worker);
mp->m_kobj.kobject.kset = xfs_kset;
return mp;
}
STATIC int
xfs_fs_fill_super(
struct super_block *sb,
@ -1589,19 +1614,13 @@ xfs_fs_fill_super(
struct xfs_mount *mp = NULL;
int flags = 0, error = -ENOMEM;
mp = kzalloc(sizeof(struct xfs_mount), GFP_KERNEL);
/*
* allocate mp and do all low-level struct initializations before we
* attach it to the super
*/
mp = xfs_mount_alloc(sb);
if (!mp)
goto out;
spin_lock_init(&mp->m_sb_lock);
mutex_init(&mp->m_growlock);
atomic_set(&mp->m_active_trans, 0);
INIT_DELAYED_WORK(&mp->m_reclaim_work, xfs_reclaim_worker);
INIT_DELAYED_WORK(&mp->m_eofblocks_work, xfs_eofblocks_worker);
INIT_DELAYED_WORK(&mp->m_cowblocks_work, xfs_cowblocks_worker);
mp->m_kobj.kobject.kset = xfs_kset;
mp->m_super = sb;
sb->s_fs_info = mp;
error = xfs_parseargs(mp, (char *)data);