[PATCH v1 5/7] tools/libxc: add xc_ptbuf_* functions

["Michał Leszczyński" <michal.leszczynski@cert.pl>]

Add functions in libxc that use the new HVMOP_vmtrace interface.

Signed-off-by: Michal Leszczynski <michal.leszczynski@cert.pl>
---
 tools/libxc/include/xenctrl.h |  59 +++++++++++++++++++
 tools/libxc/xc_tbuf.c         | 108 ++++++++++++++++++++++++++++++++++
 2 files changed, 167 insertions(+)

diff --git a/tools/libxc/include/xenctrl.h b/tools/libxc/include/xenctrl.h
index 113ddd935d..0a972deb7d 100644
--- a/tools/libxc/include/xenctrl.h
+++ b/tools/libxc/include/xenctrl.h
@@ -1585,6 +1585,65 @@ int xc_tbuf_set_cpu_mask(xc_interface *xch, xc_cpumap_t mask);
 
 int xc_tbuf_set_evt_mask(xc_interface *xch, uint32_t mask);
 
+/**
+ * Enable Intel Processor Trace for given vCPU in given DomU.
+ * Allocate the trace ringbuffer with given size.
+ *
+ * @parm xch a handle to an open hypervisor interface
+ * @parm domid domain identifier
+ * @parm vcpu vcpu identifier
+ * @parm size trace buffer size in bytes, must be power of 2, between 4 kB and 4 GB
+ * @return 0 on success, -1 on failure
+ */
+int xc_ptbuf_enable(xc_interface *xch, uint32_t domid, uint32_t vcpu, uint64_t size);
+
+/**
+ * Disable Intel Processor Trace for given vCPU in given DomU.
+ * Deallocate the trace ringbuffer.
+ *
+ * @parm xch a handle to an open hypervisor interface
+ * @parm domid domain identifier
+ * @parm vcpu vcpu identifier
+ * @return 0 on success, -1 on failure
+ */
+int xc_ptbuf_disable(xc_interface *xch, uint32_t domid, uint32_t vcpu);
+
+/**
+ * Map the trace buffer into Dom0.
+ *
+ * @parm xch a handle to an open hypervisor interface
+ * @parm domid domain identifier
+ * @parm vcpu vcpu identifier
+ * @parm buf pointer to the mapped buffer will be written there
+ * @parm trace buffer size (in bytes) will be written there
+ * @return 0 on success, -1 on failure
+ */
+int xc_ptbuf_map(xc_interface *xch, uint32_t domid, uint32_t vcpu, uint8_t **buf, uint64_t *size);
+
+/**
+ * Unmap the trace buffer from Dom0.
+ *
+ * @parm xch a handle to an open hypervisor interface
+ * @parm buf pointer to the mapped buffer
+ * @parm size of the trace buffer (in bytes)
+ * @return 0 on success, -1 on failure
+ */
+int xc_ptbuf_unmap(xc_interface *xch, uint8_t *buf, uint64_t size);
+
+/**
+ * Get current offset inside the trace ringbuffer.
+ * This allows to determine how much data was written into the buffer.
+ * Once buffer overflows, the offset will reset to 0 and the previous
+ * data will be overriden.
+ *
+ * @parm xch a handle to an open hypervisor interface
+ * @parm domid domain identifier
+ * @parm vcpu vcpu identifier
+ * @parm offset current offset inside trace buffer will be written there
+ * @return 0 on success, -1 on failure
+ */
+int xc_ptbuf_get_offset(xc_interface *xch, uint32_t domid, uint32_t vcpu, uint64_t *offset);
+
 int xc_domctl(xc_interface *xch, struct xen_domctl *domctl);
 int xc_sysctl(xc_interface *xch, struct xen_sysctl *sysctl);
 
diff --git a/tools/libxc/xc_tbuf.c b/tools/libxc/xc_tbuf.c
index 283fbd1c8f..8fab7f7d79 100644
--- a/tools/libxc/xc_tbuf.c
+++ b/tools/libxc/xc_tbuf.c
@@ -79,6 +79,114 @@ int xc_tbuf_get_size(xc_interface *xch, unsigned long *size)
     return rc;
 }
 
+int xc_ptbuf_enable(xc_interface *xch, uint32_t domid, uint32_t vcpu, uint64_t size)
+{
+    DECLARE_HYPERCALL_BUFFER(xen_hvm_vmtrace_op_t, arg);
+    int rc = -1;
+
+    arg = xc_hypercall_buffer_alloc(xch, arg, sizeof(*arg));
+    if ( arg == NULL )
+        return -1;
+
+    arg->version = HVMOP_VMTRACE_INTERFACE_VERSION;
+    arg->cmd = HVMOP_vmtrace_ipt_enable;
+    arg->domain = domid;
+    arg->vcpu = vcpu;
+    arg->size = size;
+
+    rc = xencall2(xch->xcall, __HYPERVISOR_hvm_op, HVMOP_vmtrace,
+                  HYPERCALL_BUFFER_AS_ARG(arg));
+
+    xc_hypercall_buffer_free(xch, arg);
+    return rc;
+}
+
+int xc_ptbuf_get_offset(xc_interface *xch, uint32_t domid, uint32_t vcpu, uint64_t *offset)
+{
+    DECLARE_HYPERCALL_BUFFER(xen_hvm_vmtrace_op_t, arg);
+    int rc = -1;
+
+    arg = xc_hypercall_buffer_alloc(xch, arg, sizeof(*arg));
+    if ( arg == NULL )
+        return -1;
+
+    arg->version = HVMOP_VMTRACE_INTERFACE_VERSION;
+    arg->cmd = HVMOP_vmtrace_ipt_get_offset;
+    arg->domain = domid;
+    arg->vcpu = vcpu;
+
+    rc = xencall2(xch->xcall, __HYPERVISOR_hvm_op, HVMOP_vmtrace,
+                  HYPERCALL_BUFFER_AS_ARG(arg));
+
+    if ( rc == 0 )
+    {
+        *offset = arg->offset;
+    }
+
+    xc_hypercall_buffer_free(xch, arg);
+    return rc;
+}
+
+int xc_ptbuf_map(xc_interface *xch, uint32_t domid, uint32_t vcpu, uint8_t **buf, uint64_t *size)
+{
+    DECLARE_HYPERCALL_BUFFER(xen_hvm_vmtrace_op_t, arg);
+    int rc = -1;
+    uint8_t *mapped_buf;
+
+    arg = xc_hypercall_buffer_alloc(xch, arg, sizeof(*arg));
+    if ( arg == NULL )
+        return -1;
+
+    arg->version = HVMOP_VMTRACE_INTERFACE_VERSION;
+    arg->cmd = HVMOP_vmtrace_ipt_get_buf;
+    arg->domain = domid;
+    arg->vcpu = vcpu;
+
+    rc = xencall2(xch->xcall, __HYPERVISOR_hvm_op, HVMOP_vmtrace,
+                  HYPERCALL_BUFFER_AS_ARG(arg));
+
+    if ( rc == 0 )
+    {
+        mapped_buf = (uint8_t *)xc_map_foreign_range(xch, DOMID_XEN, arg->size, PROT_READ, arg->mfn);
+
+        if ( mapped_buf == NULL )
+            return -1;
+
+        *buf = mapped_buf;
+        *size = arg->size;
+    }
+
+    xc_hypercall_buffer_free(xch, arg);
+    return rc;
+}
+
+int xc_ptbuf_unmap(xc_interface *xch, uint8_t *buf, uint64_t size)
+{
+    xenforeignmemory_unmap(xch->fmem, buf, size >> PAGE_SHIFT);
+    return 0;
+}
+
+int xc_ptbuf_disable(xc_interface *xch, uint32_t domid, uint32_t vcpu)
+{
+    DECLARE_HYPERCALL_BUFFER(xen_hvm_vmtrace_op_t, arg);
+    int rc = -1;
+
+    arg = xc_hypercall_buffer_alloc(xch, arg, sizeof(*arg));
+    if ( arg == NULL )
+        return -1;
+
+    arg->version = HVMOP_VMTRACE_INTERFACE_VERSION;
+    arg->cmd = HVMOP_vmtrace_ipt_disable;
+    arg->domain = domid;
+    arg->vcpu = vcpu;
+
+    rc = xencall2(xch->xcall, __HYPERVISOR_hvm_op, HVMOP_vmtrace,
+                  HYPERCALL_BUFFER_AS_ARG(arg));
+
+    xc_hypercall_buffer_free(xch, arg);
+    return rc;
+}
+
 int xc_tbuf_enable(xc_interface *xch, unsigned long pages, unsigned long *mfn,
                    unsigned long *size)
 {
-- 
2.20.1