ceph: map snapid to anonymous bdev ID

ceph_getattr() return zero dev ID for head inodes and set dev ID to
snapid directly for snaphost inodes. This is not good because userspace
utilities may consider device ID of 0 as invalid, snapid may conflict
with other device's ID.

This patch introduces "snapids to anonymous bdev IDs" map. we create a
new mapping when we see a snapid for the first time. we trim unused
mapping after it is ilde for 5 minutes.

Link: http://tracker.ceph.com/issues/22353
Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
This commit is contained in:
Yan, Zheng
2017-12-14 15:11:09 +08:00
committed by Ilya Dryomov
parent 81c5a1487e
commit 75c9627efb
5 changed files with 210 additions and 17 deletions

View File

@@ -548,17 +548,22 @@ void ceph_destroy_inode(struct inode *inode)
*/
if (ci->i_snap_realm) {
struct ceph_mds_client *mdsc =
ceph_sb_to_client(ci->vfs_inode.i_sb)->mdsc;
struct ceph_snap_realm *realm = ci->i_snap_realm;
dout(" dropping residual ref to snap realm %p\n", realm);
spin_lock(&realm->inodes_with_caps_lock);
list_del_init(&ci->i_snap_realm_item);
ci->i_snap_realm = NULL;
if (realm->ino == ci->i_vino.ino)
realm->inode = NULL;
spin_unlock(&realm->inodes_with_caps_lock);
ceph_put_snap_realm(mdsc, realm);
ceph_inode_to_client(inode)->mdsc;
if (ceph_snap(inode) == CEPH_NOSNAP) {
struct ceph_snap_realm *realm = ci->i_snap_realm;
dout(" dropping residual ref to snap realm %p\n",
realm);
spin_lock(&realm->inodes_with_caps_lock);
list_del_init(&ci->i_snap_realm_item);
ci->i_snap_realm = NULL;
if (realm->ino == ci->i_vino.ino)
realm->inode = NULL;
spin_unlock(&realm->inodes_with_caps_lock);
ceph_put_snap_realm(mdsc, realm);
} else {
ceph_put_snapid_map(mdsc, ci->i_snapid_map);
ci->i_snap_realm = NULL;
}
}
kfree(ci->i_symlink);
@@ -776,6 +781,9 @@ static int fill_inode(struct inode *inode, struct page *locked_page,
pool_ns = ceph_find_or_create_string(iinfo->pool_ns_data,
iinfo->pool_ns_len);
if (ceph_snap(inode) != CEPH_NOSNAP && !ci->i_snapid_map)
ci->i_snapid_map = ceph_get_snapid_map(mdsc, ceph_snap(inode));
spin_lock(&ci->i_ceph_lock);
/*
@@ -2260,10 +2268,11 @@ int ceph_getattr(const struct path *path, struct kstat *stat,
if (!err) {
generic_fillattr(inode, stat);
stat->ino = ceph_translate_ino(inode->i_sb, inode->i_ino);
if (ceph_snap(inode) != CEPH_NOSNAP)
stat->dev = ceph_snap(inode);
if (ceph_snap(inode) == CEPH_NOSNAP)
stat->dev = inode->i_sb->s_dev;
else
stat->dev = 0;
stat->dev = ci->i_snapid_map ? ci->i_snapid_map->dev : 0;
if (S_ISDIR(inode->i_mode)) {
if (ceph_test_mount_opt(ceph_sb_to_client(inode->i_sb),
RBYTES))