On 01/16/2017 11:13 AM, Junxiao Bi wrote: > On 01/16/2017 11:06 AM, Eric Ren wrote: >> Hi Junxiao, >> >> On 01/16/2017 10:46 AM, Junxiao Bi wrote: >>>>> If had_lock==true, it is a bug? I think we should BUG_ON for it, that >>>>> can help us catch bug at the first time. >>>> Good idea! But I'm not sure if "ocfs2_setattr" is always the first one >>>> who takes the cluster lock. >>>> It's harder for me to name all the possible paths;-/ >>> The BUG_ON() can help catch the path where ocfs2_setattr is not the >>> first one. >> Yes, I understand. But, the problem is that the vfs entries calling >> order is out of our control. >> I don't want to place an assertion where I'm not 100% sure it's >> absolutely right;-) > If it is not the first one, is it another recursive locking bug? In this > case, if you don't like BUG_ON(), you can dump the call trace and print > some warning message.
Yes! I like this idea, will add it in next version, thanks! Eric > > Thanks, > Junxiao. >> Thanks, >> Eric >> >>> Thanks, >>> Junxiao. >>> >>>>>> + if (had_lock) >>>>>> + arg_flags = OCFS2_META_LOCK_GETBH; >>>>>> + status = ocfs2_inode_lock_full(inode, &bh, 1, arg_flags); >>>>>> if (status < 0) { >>>>>> if (status != -ENOENT) >>>>>> mlog_errno(status); >>>>>> goto bail_unlock_rw; >>>>>> } >>>>>> - inode_locked = 1; >>>>>> + if (!had_lock) { >>>>>> + ocfs2_add_holder(lockres, &oh); >>>>>> + inode_locked = 1; >>>>>> + } >>>>>> if (size_change) { >>>>>> status = inode_newsize_ok(inode, attr->ia_size); >>>>>> @@ -1260,7 +1270,8 @@ int ocfs2_setattr(struct dentry *dentry, struct >>>>>> iattr *attr) >>>>>> bail_commit: >>>>>> ocfs2_commit_trans(osb, handle); >>>>>> bail_unlock: >>>>>> - if (status) { >>>>>> + if (status && inode_locked) { >>>>>> + ocfs2_remove_holder(lockres, &oh); >>>>>> ocfs2_inode_unlock(inode, 1); >>>>>> inode_locked = 0; >>>>>> } >>>>>> @@ -1278,8 +1289,10 @@ int ocfs2_setattr(struct dentry *dentry, >>>>>> struct iattr *attr) >>>>>> if (status < 0) >>>>>> mlog_errno(status); >>>>>> } >>>>>> - if (inode_locked) >>>>>> + if (inode_locked) { >>>>>> + ocfs2_remove_holder(lockres, &oh); >>>>>> ocfs2_inode_unlock(inode, 1); >>>>>> + } >>>>>> brelse(bh); >>>>>> return status; >>>>>> @@ -1321,20 +1334,31 @@ int ocfs2_getattr(struct vfsmount *mnt, >>>>>> int ocfs2_permission(struct inode *inode, int mask) >>>>>> { >>>>>> int ret; >>>>>> + int has_locked; >>>>>> + struct ocfs2_holder oh; >>>>>> + struct ocfs2_lock_res *lockres; >>>>>> if (mask & MAY_NOT_BLOCK) >>>>>> return -ECHILD; >>>>>> - ret = ocfs2_inode_lock(inode, NULL, 0); >>>>>> - if (ret) { >>>>>> - if (ret != -ENOENT) >>>>>> - mlog_errno(ret); >>>>>> - goto out; >>>>>> + lockres = &OCFS2_I(inode)->ip_inode_lockres; >>>>>> + has_locked = (ocfs2_is_locked_by_me(lockres) != NULL); >>>>> The same thing as ocfs2_setattr. >>>> OK. I will think over your suggestions! >>>> >>>> Thanks, >>>> Eric >>>> >>>>> Thanks, >>>>> Junxiao. >>>>>> + if (!has_locked) { >>>>>> + ret = ocfs2_inode_lock(inode, NULL, 0); >>>>>> + if (ret) { >>>>>> + if (ret != -ENOENT) >>>>>> + mlog_errno(ret); >>>>>> + goto out; >>>>>> + } >>>>>> + ocfs2_add_holder(lockres, &oh); >>>>>> } >>>>>> ret = generic_permission(inode, mask); >>>>>> - ocfs2_inode_unlock(inode, 0); >>>>>> + if (!has_locked) { >>>>>> + ocfs2_remove_holder(lockres, &oh); >>>>>> + ocfs2_inode_unlock(inode, 0); >>>>>> + } >>>>>> out: >>>>>> return ret; >>>>>> } >>>>>> > _______________________________________________ Ocfs2-devel mailing list Ocfs2-devel@oss.oracle.com https://oss.oracle.com/mailman/listinfo/ocfs2-devel