ocfs2: bugfix for hard readonly mount

Quoted 18 lines · Tiger Yang

These four patches are all related to ocfs2 on hard readonly mount. patch 1 fix oops when umount ocfs2 on hard readonly device. Because ocfs2_dismount_volume() will call ocfs2_cluster_hangup() and then call ocfs2_stack_driver_put(), will hit BUG_ON(active_stack == NULL).

patch 2 fix oops when do ls or cat in ocfs2 on hard readonly device. Because ocfs2_open_lock() will call ocfs2_cluster_lock() and then call ocfs2_dlm_lock(), but active_stack is NULL.

patch 3 fix bug of http://oss.oracle.com/bugzilla/show_bug.cgi?id=1322
ocfs2_statfs, ocfs2_fiemap, ocfs2_get_acl, ocfs2_listxattr and ocfs2_xattr_get need ocfs2_inode_lock to get dinode buffer head, but on hard readonly mount, they did not get they expected, so lead to oops. ocfs2_init_security_and_acl and ocfs2_test_inode_bit also called ocfs2_inode_lock(inode, &bh, 0), but they are safe, because ocfs2_reflink and ocfs2_get_dentry check hard read only before them.

Quoted 3 lines

patch 4 fix problem of running ls on hard readonly mount can't get the right result.
Because ocfs2_dentry_lock() return -EROFS. It should return 0.

Tiger, Thanks. Was this tested with all fs-features enabled? I am worried about quotas. If not, please test that.

Tristan, Please can you cross check these patches. Enable all features in a volume, make it readonly and do mount, ls -lR, umount, read, stat, stat -f. This calls for a test script. We should be able to use loopback. losetup -rf.

Thanks
Sunil