libsel4platsupport: Refactor IO-related interfaces
This refactoring is intended to bring these interface initialisation
functions more in line with the style of similar functions. Instead of
accepting an rvalue (or an expression) of the interfaces, we accept a
pointer to the interfaces themselves. Also add a warning regarding
lifetimes and concurrency.
diff --git a/libsel4platsupport/include/sel4platsupport/io.h b/libsel4platsupport/include/sel4platsupport/io.h
index f6d4986..e947030 100644
--- a/libsel4platsupport/include/sel4platsupport/io.h
+++ b/libsel4platsupport/include/sel4platsupport/io.h
@@ -21,6 +21,16 @@
#include <stdlib.h>
#include <stdio.h>
+/*
+ * NOTE: All vspace, vka, simple interfaces that are passed in *MUST* remain
+ * valid for the lifetime of these interfaces.
+ *
+ * Additionally, these interfaces are not thread-safe, so care must be taken to
+ * ensure that synchronisation is controlled externally. This also includes the
+ * simple, vspace and vka interfaces that were passed in to initialise these
+ * interfaces.
+ */
+
/**
* Creates a new implementation of the platsupport io_mapper interface using a
* provided simple, vspace and vka
@@ -31,7 +41,7 @@
*
* @return returns 0 on success
*/
-int sel4platsupport_new_io_mapper(vspace_t vspace, vka_t vka, ps_io_mapper_t *io_mapper);
+int sel4platsupport_new_io_mapper(vspace_t *vspace, vka_t *vka, ps_io_mapper_t *io_mapper);
/**
* Create a new malloc ops using stdlib malloc, calloc and free.
@@ -61,15 +71,15 @@
*
* @return returns 0 on success
*/
-int sel4platsupport_new_io_ops(vspace_t vspace, vka_t vka, ps_io_ops_t *io_ops);
+int sel4platsupport_new_io_ops(vspace_t *vspace, vka_t *vka, ps_io_ops_t *io_ops);
/* Initialise all arch-specific io ops for this platform
*
* sel4platsupport_new_io_ops should have already populated relevant non-arch specific
* io ops (memory allocation, mapping).
*
- * @param simple a simple interface which must remain valid after this call.
- * @param vka a vka interface which must remain valid after this call.
+ * @param simple a simple interface
+ * @param vka a vka interface
* @return 0 on success.
*/
int sel4platsupport_new_arch_ops(ps_io_ops_t *ops, simple_t *simple, vka_t *vka);
diff --git a/libsel4platsupport/src/io.c b/libsel4platsupport/src/io.c
index 500bf16..151c5ea 100644
--- a/libsel4platsupport/src/io.c
+++ b/libsel4platsupport/src/io.c
@@ -43,8 +43,8 @@
} io_mapping_t;
typedef struct sel4platsupport_io_mapper_cookie {
- vspace_t vspace;
- vka_t vka;
+ vspace_t *vspace;
+ vka_t *vka;
io_mapping_t *head;
} sel4platsupport_io_mapper_cookie_t;
@@ -137,8 +137,8 @@
size_t size, size_t page_size_bits, bool cached)
{
- vka_t *vka = &io_mapper->vka;
- vspace_t *vspace = &io_mapper->vspace;
+ vka_t *vka = io_mapper->vka;
+ vspace_t *vspace = io_mapper->vspace;
/* search at start of page */
int page_size = BIT(page_size_bits);
@@ -228,8 +228,8 @@
{
sel4platsupport_io_mapper_cookie_t *io_mapper = cookie;
- vspace_t *vspace = &io_mapper->vspace;
- vka_t *vka = &io_mapper->vka;
+ vspace_t *vspace = io_mapper->vspace;
+ vka_t *vka = io_mapper->vka;
io_mapping_t *mapping = find_node(io_mapper, vaddr);
if (!mapping) {
@@ -246,7 +246,7 @@
destroy_node(vka, mapping);
}
-int sel4platsupport_new_io_mapper(vspace_t vspace, vka_t vka, ps_io_mapper_t *io_mapper)
+int sel4platsupport_new_io_mapper(vspace_t *vspace, vka_t *vka, ps_io_mapper_t *io_mapper)
{
sel4platsupport_io_mapper_cookie_t *cookie = calloc(1, sizeof(sel4platsupport_io_mapper_cookie_t));
if (!cookie) {
@@ -331,7 +331,7 @@
#endif
}
-int sel4platsupport_new_io_ops(vspace_t vspace, vka_t vka, ps_io_ops_t *io_ops)
+int sel4platsupport_new_io_ops(vspace_t *vspace, vka_t *vka, ps_io_ops_t *io_ops)
{
memset(io_ops, 0, sizeof(ps_io_ops_t));
