Hi,
On 28/07/2021 11:27, Penny Zheng wrote:
This commit checks "xen,static-mem" device tree property in /domUx node,
to determine whether domain is on Static Allocation, when constructing
domain during boot-up.
Right now, the implementation of allocate_static_memory is missing, and
will be introduced later. It just BUG() out at the moment.
I think the code is small enough to fold it in patch #10. In fact...
Signed-off-by: Penny Zheng <penny.zh...@arm.com>
---
xen/arch/arm/domain_build.c | 37 ++++++++++++++++++++++++++++++++++++-
1 file changed, 36 insertions(+), 1 deletion(-)
diff --git a/xen/arch/arm/domain_build.c b/xen/arch/arm/domain_build.c
index 6c86d52781..cdb16f2086 100644
--- a/xen/arch/arm/domain_build.c
+++ b/xen/arch/arm/domain_build.c
@@ -2425,6 +2425,37 @@ static int __init construct_domU(struct domain *d,
struct kernel_info kinfo = {};
int rc;
u64 mem;
+ const struct dt_property *static_mem_prop;
+ u32 static_mem_addr_cells, static_mem_size_cells;
+ bool static_mem = false;
You don't need those information outside of allocate_static_memory(). So
I think it would be best to move the code in that function.
+
+ /*
+ * Guest RAM could be static memory which will be specified through
+ * "xen,static-mem" property.
+ */
+ static_mem_prop = dt_find_property(node, "xen,static-mem", NULL);
+ if ( static_mem_prop )
+ {
+ static_mem = true;
+
+ if ( !dt_property_read_u32(node, "#xen,static-mem-address-cells",
+ &static_mem_addr_cells) )
+ {
+ printk("Error building DomU: cannot read "
+ "\"#xen,static-mem-address-cells\" property\n");
We don't split comment over multi-line (even they are more than 80
characters). This is to help grep message in the code.
Although for this one I would replaced "Error building Domu:" with
simply with the domain ID (you can use %pd and 'd'). The caller will
then print there was an error during building.
+ return -EINVAL;
+ }
+
+ if ( !dt_property_read_u32(node, "#xen,static-mem-size-cells",
+ &static_mem_size_cells) )
+ {
+ printk("Error building DomU: cannot read "
+ "\"#xen,static-mem-size-cells\" property\n");
My remark applies here as well.
+ return -EINVAL;
+ }
+
+ BUG_ON(static_mem_size_cells > 2 || static_mem_addr_cells > 2);
Did we validate the DT before hand? If not, then I think
+ }
rc = dt_property_read_u64(node, "memory", &mem);
if ( !rc )
@@ -2452,7 +2483,11 @@ static int __init construct_domU(struct domain *d,
/* type must be set before allocate memory */
d->arch.type = kinfo.type;
#endif
- allocate_memory(d, &kinfo);
+ if ( !static_mem )
With my suggestion above, the check can be replaced with:
if ( !dt_find_property(node, "xen,static-mem", NULL) )
+ allocate_memory(d, &kinfo);
+ else
+ /* TODO: allocate_static_memory(...). */
+ BUG();
rc = prepare_dtb_domU(d, &kinfo);
if ( rc < 0 )
Cheers,
--
Julien Grall
