[PATCH] xen: don't compile pv-specific parts if XEN_PV isn't configured

From: Juergen Gross
Date: Thu Sep 14 2017 - 08:39:06 EST


xenbus_client.c contains some functions specific for pv guests.
Enclose them with #ifdef CONFIG_XEN_PV to avoid compiling them when
they are not needed (e.g. on ARM).

Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
---
drivers/xen/xenbus/xenbus_client.c | 130 +++++++++++++++++++------------------
1 file changed, 67 insertions(+), 63 deletions(-)

diff --git a/drivers/xen/xenbus/xenbus_client.c b/drivers/xen/xenbus/xenbus_client.c
index 82a8866758ee..a1c17000129b 100644
--- a/drivers/xen/xenbus/xenbus_client.c
+++ b/drivers/xen/xenbus/xenbus_client.c
@@ -519,64 +519,6 @@ static int __xenbus_map_ring(struct xenbus_device *dev,
return err;
}

-static int xenbus_map_ring_valloc_pv(struct xenbus_device *dev,
- grant_ref_t *gnt_refs,
- unsigned int nr_grefs,
- void **vaddr)
-{
- struct xenbus_map_node *node;
- struct vm_struct *area;
- pte_t *ptes[XENBUS_MAX_RING_GRANTS];
- phys_addr_t phys_addrs[XENBUS_MAX_RING_GRANTS];
- int err = GNTST_okay;
- int i;
- bool leaked;
-
- *vaddr = NULL;
-
- if (nr_grefs > XENBUS_MAX_RING_GRANTS)
- return -EINVAL;
-
- node = kzalloc(sizeof(*node), GFP_KERNEL);
- if (!node)
- return -ENOMEM;
-
- area = alloc_vm_area(XEN_PAGE_SIZE * nr_grefs, ptes);
- if (!area) {
- kfree(node);
- return -ENOMEM;
- }
-
- for (i = 0; i < nr_grefs; i++)
- phys_addrs[i] = arbitrary_virt_to_machine(ptes[i]).maddr;
-
- err = __xenbus_map_ring(dev, gnt_refs, nr_grefs, node->handles,
- phys_addrs,
- GNTMAP_host_map | GNTMAP_contains_pte,
- &leaked);
- if (err)
- goto failed;
-
- node->nr_handles = nr_grefs;
- node->pv.area = area;
-
- spin_lock(&xenbus_valloc_lock);
- list_add(&node->next, &xenbus_valloc_pages);
- spin_unlock(&xenbus_valloc_lock);
-
- *vaddr = area->addr;
- return 0;
-
-failed:
- if (!leaked)
- free_vm_area(area);
- else
- pr_alert("leaking VM area %p size %u page(s)", area, nr_grefs);
-
- kfree(node);
- return err;
-}
-
struct map_ring_valloc_hvm
{
unsigned int idx;
@@ -725,6 +667,65 @@ int xenbus_unmap_ring_vfree(struct xenbus_device *dev, void *vaddr)
}
EXPORT_SYMBOL_GPL(xenbus_unmap_ring_vfree);

+#ifdef CONFIG_XEN_PV
+static int xenbus_map_ring_valloc_pv(struct xenbus_device *dev,
+ grant_ref_t *gnt_refs,
+ unsigned int nr_grefs,
+ void **vaddr)
+{
+ struct xenbus_map_node *node;
+ struct vm_struct *area;
+ pte_t *ptes[XENBUS_MAX_RING_GRANTS];
+ phys_addr_t phys_addrs[XENBUS_MAX_RING_GRANTS];
+ int err = GNTST_okay;
+ int i;
+ bool leaked;
+
+ *vaddr = NULL;
+
+ if (nr_grefs > XENBUS_MAX_RING_GRANTS)
+ return -EINVAL;
+
+ node = kzalloc(sizeof(*node), GFP_KERNEL);
+ if (!node)
+ return -ENOMEM;
+
+ area = alloc_vm_area(XEN_PAGE_SIZE * nr_grefs, ptes);
+ if (!area) {
+ kfree(node);
+ return -ENOMEM;
+ }
+
+ for (i = 0; i < nr_grefs; i++)
+ phys_addrs[i] = arbitrary_virt_to_machine(ptes[i]).maddr;
+
+ err = __xenbus_map_ring(dev, gnt_refs, nr_grefs, node->handles,
+ phys_addrs,
+ GNTMAP_host_map | GNTMAP_contains_pte,
+ &leaked);
+ if (err)
+ goto failed;
+
+ node->nr_handles = nr_grefs;
+ node->pv.area = area;
+
+ spin_lock(&xenbus_valloc_lock);
+ list_add(&node->next, &xenbus_valloc_pages);
+ spin_unlock(&xenbus_valloc_lock);
+
+ *vaddr = area->addr;
+ return 0;
+
+failed:
+ if (!leaked)
+ free_vm_area(area);
+ else
+ pr_alert("leaking VM area %p size %u page(s)", area, nr_grefs);
+
+ kfree(node);
+ return err;
+}
+
static int xenbus_unmap_ring_vfree_pv(struct xenbus_device *dev, void *vaddr)
{
struct xenbus_map_node *node;
@@ -788,6 +789,12 @@ static int xenbus_unmap_ring_vfree_pv(struct xenbus_device *dev, void *vaddr)
return err;
}

+static const struct xenbus_ring_ops ring_ops_pv = {
+ .map = xenbus_map_ring_valloc_pv,
+ .unmap = xenbus_unmap_ring_vfree_pv,
+};
+#endif
+
struct unmap_ring_vfree_hvm
{
unsigned int idx;
@@ -916,11 +923,6 @@ enum xenbus_state xenbus_read_driver_state(const char *path)
}
EXPORT_SYMBOL_GPL(xenbus_read_driver_state);

-static const struct xenbus_ring_ops ring_ops_pv = {
- .map = xenbus_map_ring_valloc_pv,
- .unmap = xenbus_unmap_ring_vfree_pv,
-};
-
static const struct xenbus_ring_ops ring_ops_hvm = {
.map = xenbus_map_ring_valloc_hvm,
.unmap = xenbus_unmap_ring_vfree_hvm,
@@ -928,8 +930,10 @@ static const struct xenbus_ring_ops ring_ops_hvm = {

void __init xenbus_ring_ops_init(void)
{
+#ifdef CONFIG_XEN_PV
if (!xen_feature(XENFEAT_auto_translated_physmap))
ring_ops = &ring_ops_pv;
else
+#endif
ring_ops = &ring_ops_hvm;
}
--
2.12.3