[PATCH 1/2] tools/libs/evtchn: decouple more from mini-os

[Juergen Gross <jgross@xxxxxxxx>]

Mini-OS and libevtchn are using implementation details of each other.
Change that by letting libevtchn use the new get_file_from_fd()
function and the generic dev pointer of struct file from Mini-OS.

By using private struct declarations Mini-OS will be able to drop the
libevtchn specific definitions of struct evtchn_port_info and
evtchn_port_list in future.

Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
---
 tools/libs/evtchn/minios.c | 82 +++++++++++++++++++++++++++-----------
 1 file changed, 58 insertions(+), 24 deletions(-)

diff --git a/tools/libs/evtchn/minios.c b/tools/libs/evtchn/minios.c
index e5dfdc5ef5..3305102f22 100644
--- a/tools/libs/evtchn/minios.c
+++ b/tools/libs/evtchn/minios.c
@@ -38,16 +38,27 @@
 
 #include "private.h"
 
+LIST_HEAD(port_list, port_info);
+
+struct port_info {
+    LIST_ENTRY(port_info) list;
+    evtchn_port_t port;
+    unsigned long pending;
+    int bound;
+};
+
 extern void minios_evtchn_close_fd(int fd);
 
 extern struct wait_queue_head event_queue;
 
 /* XXX Note: This is not threadsafe */
-static struct evtchn_port_info *port_alloc(int fd)
+static struct port_info *port_alloc(int fd)
 {
-    struct evtchn_port_info *port_info;
+    struct port_info *port_info;
+    struct file *file = get_file_from_fd(fd);
+    struct port_list *port_list = file->dev;
 
-    port_info = malloc(sizeof(struct evtchn_port_info));
+    port_info = malloc(sizeof(struct port_info));
     if ( port_info == NULL )
         return NULL;
 
@@ -55,12 +66,12 @@ static struct evtchn_port_info *port_alloc(int fd)
     port_info->port = -1;
     port_info->bound = 0;
 
-    LIST_INSERT_HEAD(&files[fd].evtchn.ports, port_info, list);
+    LIST_INSERT_HEAD(port_list, port_info, list);
 
     return port_info;
 }
 
-static void port_dealloc(struct evtchn_port_info *port_info)
+static void port_dealloc(struct port_info *port_info)
 {
     if ( port_info->bound )
         unbind_evtchn(port_info->port);
@@ -75,12 +86,25 @@ static void port_dealloc(struct evtchn_port_info *port_info)
  */
 int osdep_evtchn_open(xenevtchn_handle *xce, unsigned int flags)
 {
-    int fd = alloc_fd(FTYPE_EVTCHN);
+    int fd;
+    struct file *file;
+    struct port_list *list;
+
+    list = malloc(sizeof(*list));
+    if ( !list )
+        return -1;
+
+    fd = alloc_fd(FTYPE_EVTCHN);
+    file = get_file_from_fd(fd);
 
-    if ( fd == -1 )
+    if ( !file )
+    {
+        free(list);
         return -1;
+    }
 
-    LIST_INIT(&files[fd].evtchn.ports);
+    file->dev = list;
+    LIST_INIT(list);
     xce->fd = fd;
     printf("evtchn_open() -> %d\n", fd);
 
@@ -104,12 +128,15 @@ int osdep_evtchn_restrict(xenevtchn_handle *xce, domid_t 
domid)
 
 void minios_evtchn_close_fd(int fd)
 {
-    struct evtchn_port_info *port_info, *tmp;
+    struct port_info *port_info, *tmp;
+    struct file *file = get_file_from_fd(fd);
+    struct port_list *port_list = file->dev;
 
-    LIST_FOREACH_SAFE(port_info, &files[fd].evtchn.ports, list, tmp)
+    LIST_FOREACH_SAFE(port_info, port_list, list, tmp)
         port_dealloc(port_info);
+    free(port_list);
 
-    files[fd].type = FTYPE_NONE;
+    file->type = FTYPE_NONE;
 }
 
 int xenevtchn_fd(xenevtchn_handle *xce)
@@ -135,11 +162,14 @@ int xenevtchn_notify(xenevtchn_handle *xce, evtchn_port_t 
port)
 static void evtchn_handler(evtchn_port_t port, struct pt_regs *regs, void 
*data)
 {
     int fd = (int)(intptr_t)data;
-    struct evtchn_port_info *port_info;
+    struct file *file = get_file_from_fd(fd);
+    struct port_info *port_info;
+    struct port_list *port_list;
 
-    assert(files[fd].type == FTYPE_EVTCHN);
+    assert(file && file->type == FTYPE_EVTCHN);
+    port_list = file->dev;
     mask_evtchn(port);
-    LIST_FOREACH(port_info, &files[fd].evtchn.ports, list)
+    LIST_FOREACH(port_info, port_list, list)
     {
         if ( port_info->port == port )
             goto found;
@@ -150,7 +180,7 @@ static void evtchn_handler(evtchn_port_t port, struct 
pt_regs *regs, void *data)
 
  found:
     port_info->pending = 1;
-    files[fd].read = 1;
+    file->read = 1;
     wake_up(&event_queue);
 }
 
@@ -158,7 +188,7 @@ xenevtchn_port_or_error_t 
xenevtchn_bind_unbound_port(xenevtchn_handle *xce,
                                                       uint32_t domid)
 {
     int fd = xce->fd;
-    struct evtchn_port_info *port_info;
+    struct port_info *port_info;
     int ret;
     evtchn_port_t port;
 
@@ -191,7 +221,7 @@ xenevtchn_port_or_error_t 
xenevtchn_bind_interdomain(xenevtchn_handle *xce,
                                                      evtchn_port_t remote_port)
 {
     int fd = xce->fd;
-    struct evtchn_port_info *port_info;
+    struct port_info *port_info;
     evtchn_port_t local_port;
     int ret;
 
@@ -222,9 +252,11 @@ xenevtchn_port_or_error_t 
xenevtchn_bind_interdomain(xenevtchn_handle *xce,
 int xenevtchn_unbind(xenevtchn_handle *xce, evtchn_port_t port)
 {
     int fd = xce->fd;
-    struct evtchn_port_info *port_info;
+    struct file *file = get_file_from_fd(fd);
+    struct port_info *port_info;
+    struct port_list *port_list = file->dev;
 
-    LIST_FOREACH(port_info, &files[fd].evtchn.ports, list)
+    LIST_FOREACH(port_info, port_list, list)
     {
         if ( port_info->port == port )
         {
@@ -244,7 +276,7 @@ xenevtchn_port_or_error_t 
xenevtchn_bind_virq(xenevtchn_handle *xce,
                                               unsigned int virq)
 {
     int fd = xce->fd;
-    struct evtchn_port_info *port_info;
+    struct port_info *port_info;
     evtchn_port_t port;
 
     assert(get_current() == main_thread);
@@ -273,15 +305,17 @@ xenevtchn_port_or_error_t 
xenevtchn_bind_virq(xenevtchn_handle *xce,
 xenevtchn_port_or_error_t xenevtchn_pending(xenevtchn_handle *xce)
 {
     int fd = xce->fd;
-    struct evtchn_port_info *port_info;
+    struct file *file = get_file_from_fd(fd);
+    struct port_info *port_info;
+    struct port_list *port_list = file->dev;
     unsigned long flags;
     evtchn_port_t ret = -1;
 
     local_irq_save(flags);
 
-    files[fd].read = 0;
+    file->read = 0;
 
-    LIST_FOREACH(port_info, &files[fd].evtchn.ports, list)
+    LIST_FOREACH(port_info, port_list, list)
     {
         if ( port_info->port != -1 && port_info->pending )
         {
@@ -292,7 +326,7 @@ xenevtchn_port_or_error_t 
xenevtchn_pending(xenevtchn_handle *xce)
             }
             else
             {
-                files[fd].read = 1;
+                file->read = 1;
                 break;
             }
         }
-- 
2.26.2