On 10/19/2015 05:21 PM, Steve French wrote:
Could you verify this over SMB2 (vers=3.0) as well? It looks like it should fail because cifs_all_info_to_fattr doesn't see the inode attribute change and fill in the new inode number (IndexNuber). I am suspicious that your patch is overkill (sends an extra request on revalidate, doubling the traffic) in the SMB2/SMB3 case since we are already doing a query file with FILE_ALL_INFO requested which already returned IndexNumber (so should have already gotten the inode number) - probably more important to use the IndexNumber we got back rather than request it twice.
It was verified with vers=3.0. It works due to the following code, where -ESTALE is returned if uniqueid has changed (this is independent of cifs_all_info_to_fattr).
@@ -814,8 +814,26 @@ cifs_get_inode_info(struct inode **inode, const char *full_path, } } else fattr.cf_uniqueid = iunique(sb, ROOT_I); - } else - fattr.cf_uniqueid = CIFS_I(*inode)->uniqueid; + } else { + if (check_inode_no && + (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM) && + server->ops->get_srv_inum) { + tmprc = server->ops->get_srv_inum(xid, + tcon, cifs_sb, full_path, + &fattr.cf_uniqueid, data); + if (tmprc) { + cifs_dbg(FYI, "GetSrvInodeNum rc %d\n", + tmprc); + fattr.cf_uniqueid = iunique(sb, ROOT_I); + cifs_autodisable_serverino(cifs_sb); + } else if (CIFS_I(*inode)->uniqueid != + fattr.cf_uniqueid) { + rc = -ESTALE; + goto cgii_exit; + } + } else + fattr.cf_uniqueid = CIFS_I(*inode)->uniqueid; + } /* query for SFU type info if supported and needed */ if (fattr.cf_cifsattrs & ATTR_SYSTEM &&
Maybe it is possible for cifs_all_info_to_fattr to update the inode number in place?
I'm a bit concerned with the approach above that it only applies when the dentry is revalidated. There are many other instances where cifs_get_inode_info is called and the inode number may have changed which this does not take care of.
I'm certainly not an expert in this area, so looking for ideas of how to solve the problem.
Thanks, -- Ross Lagerwall -- To unsubscribe from this list: send the line "unsubscribe linux-cifs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
