Change the xenbus_map_ring_valloc() interface and implementation so

that it is buildable as a module.
Signed-off-by: Jan Beulich <jbeulich@novell.com>

diff --git a/linux-2.6-xen-sparse/drivers/xen/pciback/pciback.h b/linux-2.6-xen-sparse/drivers/xen/pciback/pciback.h
index aaa0d75d3a89ac88f76a7693b767f294060bbf8c..77d63e0030e848fc3217496d30300838ed706510 100644 (file)
--- a/linux-2.6-xen-sparse/drivers/xen/pciback/pciback.h
+++ b/linux-2.6-xen-sparse/drivers/xen/pciback/pciback.h
@@ -29,6 +29,7 @@ struct pciback_device {
 
        int evtchn_irq;
 
+       struct vm_struct *sh_area;
        struct xen_pci_sharedinfo *sh_info;
 };
 

diff --git a/linux-2.6-xen-sparse/drivers/xen/pciback/xenbus.c b/linux-2.6-xen-sparse/drivers/xen/pciback/xenbus.c
index dc369d0efbb7ff1bd13f1b3a265852bfecc48670..f073b35679ae3c84ac8fd22090001b8266e5a0b5 100644 (file)
--- a/linux-2.6-xen-sparse/drivers/xen/pciback/xenbus.c
+++ b/linux-2.6-xen-sparse/drivers/xen/pciback/xenbus.c
@@ -26,6 +26,7 @@ static struct pciback_device *alloc_pdev(struct xenbus_device *xdev)
 
        spin_lock_init(&pdev->dev_lock);
 
+       pdev->sh_area = NULL;
        pdev->sh_info = NULL;
        pdev->evtchn_irq = INVALID_EVTCHN_IRQ;
        pdev->be_watching = 0;
@@ -48,7 +49,7 @@ static void free_pdev(struct pciback_device *pdev)
                unbind_from_irqhandler(pdev->evtchn_irq, pdev);
 
        if (pdev->sh_info)
-               xenbus_unmap_ring_vfree(pdev->xdev, pdev->sh_info);
+               xenbus_unmap_ring_vfree(pdev->xdev, pdev->sh_area);
 
        pciback_release_devices(pdev);
 
@@ -63,15 +64,19 @@ static int pciback_do_attach(struct pciback_device *pdev, int gnt_ref,
 {
        int err = 0;
        int evtchn;
+       struct vm_struct *area;
+
        dev_dbg(&pdev->xdev->dev,
                "Attaching to frontend resources - gnt_ref=%d evtchn=%d\n",
                gnt_ref, remote_evtchn);
 
-       err =
-           xenbus_map_ring_valloc(pdev->xdev, gnt_ref,
-                                  (void **)&pdev->sh_info);
-       if (err)
+       area = xenbus_map_ring_valloc(pdev->xdev, gnt_ref);
+       if (IS_ERR(area)) {
+               err = PTR_ERR(area);
                goto out;
+       }
+       pdev->sh_area = area;
+       pdev->sh_info = area->addr;
 
        err = xenbus_bind_evtchn(pdev->xdev, remote_evtchn, &evtchn);
        if (err)

diff --git a/linux-2.6-xen-sparse/drivers/xen/xenbus/xenbus_backend_client.c b/linux-2.6-xen-sparse/drivers/xen/xenbus/xenbus_backend_client.c
index 398541a1f363999a66707c50b6b565c44fca0340..e7a018389c4c06afef6f81a64f9379b684d92378 100644 (file)
--- a/linux-2.6-xen-sparse/drivers/xen/xenbus/xenbus_backend_client.c
+++ b/linux-2.6-xen-sparse/drivers/xen/xenbus/xenbus_backend_client.c
@@ -30,21 +30,20 @@
  * IN THE SOFTWARE.
  */
 
+#include <linux/err.h>
 #include <xen/gnttab.h>
 #include <xen/xenbus.h>
 #include <xen/driver_util.h>
 
 /* Based on Rusty Russell's skeleton driver's map_page */
-int xenbus_map_ring_valloc(struct xenbus_device *dev, int gnt_ref, void **vaddr)
+struct vm_struct *xenbus_map_ring_valloc(struct xenbus_device *dev, int gnt_ref)
 {
        struct gnttab_map_grant_ref op;
        struct vm_struct *area;
 
-       *vaddr = NULL;
-
        area = alloc_vm_area(PAGE_SIZE);
        if (!area)
-               return -ENOMEM;
+               return ERR_PTR(-ENOMEM);
 
        gnttab_set_map_op(&op, (unsigned long)area->addr, GNTMAP_host_map,
                          gnt_ref, dev->otherend_id);
@@ -58,14 +57,14 @@ int xenbus_map_ring_valloc(struct xenbus_device *dev, int gnt_ref, void **vaddr)
                xenbus_dev_fatal(dev, op.status,
                                 "mapping in shared page %d from domain %d",
                                 gnt_ref, dev->otherend_id);
-               return op.status;
+               BUG_ON(!IS_ERR(ERR_PTR(op.status)));
+               return ERR_PTR(op.status);
        }
 
        /* Stuff the handle in an unused field */
        area->phys_addr = (unsigned long)op.handle;
 
-       *vaddr = area->addr;
-       return 0;
+       return area;
 }
 EXPORT_SYMBOL_GPL(xenbus_map_ring_valloc);
 
@@ -92,30 +91,10 @@ EXPORT_SYMBOL_GPL(xenbus_map_ring);
 
 
 /* Based on Rusty Russell's skeleton driver's unmap_page */
-int xenbus_unmap_ring_vfree(struct xenbus_device *dev, void *vaddr)
+int xenbus_unmap_ring_vfree(struct xenbus_device *dev, struct vm_struct *area)
 {
-       struct vm_struct *area;
        struct gnttab_unmap_grant_ref op;
 
-       /* It'd be nice if linux/vmalloc.h provided a find_vm_area(void *addr)
-        * method so that we don't have to muck with vmalloc internals here.
-        * We could force the user to hang on to their struct vm_struct from
-        * xenbus_map_ring_valloc, but these 6 lines considerably simplify
-        * this API.
-        */
-       read_lock(&vmlist_lock);
-       for (area = vmlist; area != NULL; area = area->next) {
-               if (area->addr == vaddr)
-                       break;
-       }
-       read_unlock(&vmlist_lock);
-
-       if (!area) {
-               xenbus_dev_error(dev, -ENOENT,
-                                "can't find mapped virtual address %p", vaddr);
-               return GNTST_bad_virt_addr;
-       }
-
        gnttab_set_unmap_op(&op, (unsigned long)vaddr, GNTMAP_host_map,
                            (grant_handle_t)area->phys_addr);
 

diff --git a/linux-2.6-xen-sparse/include/xen/xenbus.h b/linux-2.6-xen-sparse/include/xen/xenbus.h
index b5a9da5f64f1aec41c95bdaf8f04a2c154c94827..ab0c59df76e04e342e6cc0ac24cad8be316861b7 100644 (file)
--- a/linux-2.6-xen-sparse/include/xen/xenbus.h
+++ b/linux-2.6-xen-sparse/include/xen/xenbus.h
@@ -228,8 +228,8 @@ int xenbus_grant_ring(struct xenbus_device *dev, unsigned long ring_mfn);
  * or -ENOMEM on error. If an error is returned, device will switch to
  * XenbusStateClosing and the error message will be saved in XenStore.
  */
-int xenbus_map_ring_valloc(struct xenbus_device *dev,
-                          int gnt_ref, void **vaddr);
+struct vm_struct *xenbus_map_ring_valloc(struct xenbus_device *dev,
+                                        int gnt_ref);
 int xenbus_map_ring(struct xenbus_device *dev, int gnt_ref,
                           grant_handle_t *handle, void *vaddr);
 
@@ -241,7 +241,7 @@ int xenbus_map_ring(struct xenbus_device *dev, int gnt_ref,
  * Returns 0 on success and returns GNTST_* on error
  * (see xen/include/interface/grant_table.h).
  */
-int xenbus_unmap_ring_vfree(struct xenbus_device *dev, void *vaddr);
+int xenbus_unmap_ring_vfree(struct xenbus_device *dev, struct vm_struct *);
 int xenbus_unmap_ring(struct xenbus_device *dev,
                      grant_handle_t handle, void *vaddr);