hw/tpm: Add internal buffer state for chunking
- Introduce GByteArray buffers to hold the command request and response data during chunked TPM CRB transactions. - Add helper function to clean them. Signed-off-by: Arun Menon <armenon@redhat.com> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> Reviewed-by: Stefan Berger <stefanb@linux.ibm.com> Link: https://lore.kernel.org/qemu-devel/20260506075813.120781-4-armenon@redhat.com Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
Arun Menon committed
May 6, 2026 at 13:28 UTC
29315d22b25930692b21f76b8c71910196bf960b
1 file changed
+29
-4
hw/tpm/tpm_crb.c
+29
-4
@@ -38,10 +38,13 @@ struct CRBState {
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TPMBackend *tpmbe;
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TPMBackendCmd cmd;
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uint32_t regs[TPM_CRB_R_MAX];
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+ size_t be_buffer_size;
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MemoryRegion mmio;
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MemoryRegion cmdmem;
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- size_t be_buffer_size;
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+ GByteArray *command_buffer;
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+ GByteArray *response_buffer;
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+ uint32_t response_offset;
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TPMPPI ppi;
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@@ -86,6 +89,13 @@ enum crb_cancel {
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#define TPM_CRB_NO_LOCALITY 0xff
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+static void tpm_crb_clear_internal_buffers(CRBState *s)
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+{
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+ g_byte_array_set_size(s->response_buffer, 0);
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+ g_byte_array_set_size(s->command_buffer, 0);
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+ s->response_offset = 0;
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+}
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+
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static uint64_t tpm_crb_mmio_read(void *opaque, hwaddr addr,
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unsigned size)
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{
@@ -135,9 +145,11 @@ static void tpm_crb_mmio_write(void *opaque, hwaddr addr,
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}
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break;
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case A_CRB_CTRL_CANCEL:
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- if (val == CRB_CANCEL_INVOKE &&
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- s->regs[R_CRB_CTRL_START] & CRB_START_INVOKE) {
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- tpm_backend_cancel_cmd(s->tpmbe);
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+ if (val == CRB_CANCEL_INVOKE) {
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+ if (s->regs[R_CRB_CTRL_START] & CRB_START_INVOKE) {
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+ tpm_backend_cancel_cmd(s->tpmbe);
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+ }
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+ tpm_crb_clear_internal_buffers(s);
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}
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break;
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case A_CRB_CTRL_START:
@@ -239,6 +251,7 @@ static void tpm_crb_reset(void *dev)
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tpm_ppi_reset(&s->ppi);
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tpm_backend_reset(s->tpmbe);
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+ tpm_crb_clear_internal_buffers(s);
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memset(s->regs, 0, sizeof(s->regs));
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@@ -305,6 +318,9 @@ static void tpm_crb_realize(DeviceState *dev, Error **errp)
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memory_region_add_subregion(get_system_memory(),
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TPM_CRB_ADDR_BASE + sizeof(s->regs), &s->cmdmem);
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+ s->command_buffer = g_byte_array_new();
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+ s->response_buffer = g_byte_array_new();
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+
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tpm_ppi_init(&s->ppi, get_system_memory(),
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TPM_PPI_ADDR_BASE, OBJECT(s));
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@@ -315,12 +331,21 @@ static void tpm_crb_realize(DeviceState *dev, Error **errp)
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}
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}
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+static void tpm_crb_unrealize(DeviceState *dev)
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+{
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+ CRBState *s = CRB(dev);
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+
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+ g_clear_pointer(&s->command_buffer, g_byte_array_unref);
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+ g_clear_pointer(&s->response_buffer, g_byte_array_unref);
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+}
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+
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static void tpm_crb_class_init(ObjectClass *klass, const void *data)
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{
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DeviceClass *dc = DEVICE_CLASS(klass);
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TPMIfClass *tc = TPM_IF_CLASS(klass);
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dc->realize = tpm_crb_realize;
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+ dc->unrealize = tpm_crb_unrealize;
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device_class_set_props(dc, tpm_crb_properties);
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dc->vmsd = &vmstate_tpm_crb;
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dc->user_creatable = true;