Re: [libvirt] [PATCH v5 04/11] Helper functions for host TPM support

On 04/12/2013 06:24 AM, Daniel P. Berrange wrote: >On Thu, Apr 11, 2013 at 04:04:46PM -0400, Stefan Berger wrote: >>Implement helper functions to find the TPM's sysfs cancel file. >> >>Signed-off-by: Stefan Berger <stefanb(a)linux.vnet.ibm.com&gt; >>Reviewed-by: Corey Bryant <coreyb(a)linux.vnet.ibm.com&gt; >>Tested-by: Corey Bryant <coreyb(a)linux.vnet.ibm.com&gt; >> >>Hmm, actually on second thoughts the entirely approach for this >>method is just flawed. >> >>In the XML description you have: >> >> <device path='/dev/tpm0'/> >> >>So we should not be iterating over /sys/fs/misc/tpmNNN at all. >>We know exactly which TPM device we want - it is 'tpm0'. Just >>kill all this pointless readdir code & pass in the device name >>we want to get the cancel path for. Indeed, the following is better: /** * virTPMFindCancelPath: * @devpath: Path to the TPM device * * Find the cancel path given the path to the TPM device */ char * virTPMFindCancelPath(const char *devpath) { char *basepath = NULL; char *path = NULL; const char *dev; if (devpath) { dev = rindex(devpath, '/');

if (dev) { dev++; if (virAsprintf(&basepath, "/sys/class/misc/%s/device", dev) < 0) { virReportOOMError(); goto cleanup; } path = virTPMCheckSysfsCancel(basepath); } else { virReportError(VIR_ERR_INTERNAL_ERROR, _("TPM device path %s is invalid"), devpath); } } else { virReportError(VIR_ERR_INTERNAL_ERROR, "%s", _("Missing TPM device path")); } cleanup: VIR_FREE(basepath); return path; }