Stefan Berger<address@hidden> writes:
This patch adds the main code of the TPM frontend driver, the TPM TIS
interface, to Qemu. The code is largely based on my previous implementation
for Xen but has been significantly extended to meet the standard's
requirements, such as the support for changing of localities and all the
functionality of the available flags.
Communication with the backend (i.e., for Xen or the libtpms-based one)
is cleanly separated through an interface which the backend driver needs
to implement.
The TPM TIS driver's backend was previously chosen in the code added
to arch_init. The frontend holds a pointer to the chosen backend (interface).
Communication with the backend is largely based on signals and conditions.
Whenever the frontend has collected a complete packet, it will signal
the backend, which then starts processing the command. Once the result
has been returned, the backend invokes a callback function
(tis_tpm_receive_cb()).
The one tricky part is support for VM suspend while the TPM is processing
a command. In this case the frontend driver is waiting for the backend
to return the result of the last command before shutting down. It waits
on a condition for a signal from the backend, which is delivered in
tis_tpm_receive_cb().
Testing the proper functioning of the different flags and localities
cannot be done from user space when running in Linux for example, since
access to the address space of the TPM TIS interface is not possible. Also
the Linux driver itself does not exercise all functionality. So, for
testing there is a fairly extensive test suite as part of the SeaBIOS patches
since from within the BIOS one can have full access to all the TPM's registers.
v3:
- prefixing functions with tis_
- added a function to the backend interface 'early_startup_tpm' that
allows to detect the presence of the block storage and gracefully fails
Qemu if it's not available. This works with migration using shared
storage but doesn't support migration with block storage migration.
For encyrypted QCoW2 and in case of a snapshot resue the late_startup_tpm
interface function is called
Signed-off-by: Stefan Berger<address@hidden>
---
hw/tpm_tis.c | 871
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 871 insertions(+)
Index: qemu-git/hw/tpm_tis.c
===================================================================
--- /dev/null
+++ qemu-git/hw/tpm_tis.c
[...]
+static void tis_reset(DeviceState *d)
+{
+ TPMState *s = container_of(d, TPMState, busdev.qdev);
+ tis_s_reset(s);
+}
+
+
+static int tis_init(ISADevice *dev)
Function not used, sure this compiles with -Werror? If not, it needs
fixing.
As far as I can see, the use is added in 03/10, where you add the
missing qdev parts. Makes it hard to review for qdev sanity, so I did
*not* do that.
+{
+ TPMState *s = DO_UPCAST(TPMState, busdev, dev);
+ int iomemtype, rc;
+
+ qemu_mutex_init(&s->state_lock);
+ qemu_cond_init(&s->from_tpm_cond);
+ qemu_cond_init(&s->to_tpm_cond);
+
+ if (active_be->init(s, tis_tpm_receive_cb)) {
+ goto err_exit;
+ }
+
+ isa_init_irq(dev,&s->irq, s->irq_num);
+
+ iomemtype = cpu_register_io_memory(tis_readfn, tis_writefn, s,
+ DEVICE_LITTLE_ENDIAN);
+ cpu_register_physical_memory(TIS_ADDR_BASE, 0x1000 * NUM_LOCALITIES,
+ iomemtype);
+
+ /*
+ * startup the TPM backend early to detect problems early
+ */
+ rc = tis_do_early_startup_tpm(s);
+ if (rc != 0&& rc != -ENOKEY) {
+ fprintf(stderr,"tpm_tis: Fatal error accessing TPM's block
storage.\n");
+ goto err_exit;
+ }
+
+ return 0;
+
+ err_exit:
+ return -1;
+}
+
Please fix "new blank line at EOF."