VMware balloon: Treat init like reset

Unify the behavior of the first start of the balloon and a reset. Also on
unload, declare that the balloon driver does not have any capabilities
anymore.

Acked-by: Andy King <acking@vmware.com>
Signed-off-by: Xavier Deguillard <xdeguillard@vmware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/misc/vmw_balloon.c b/drivers/misc/vmw_balloon.c
index 01519ff..28fe9e5 100644 (file)
--- a/drivers/misc/vmw_balloon.c
+++ b/drivers/misc/vmw_balloon.c
@@ -47,7 +47,7 @@
 
 MODULE_AUTHOR("VMware, Inc.");
 MODULE_DESCRIPTION("VMware Memory Control (Balloon) Driver");
-MODULE_VERSION("1.4.0.0-k");
+MODULE_VERSION("1.4.1.0-k");
 MODULE_ALIAS("dmi:*:svnVMware*:*");
 MODULE_ALIAS("vmware_vmmemctl");
 MODULE_LICENSE("GPL");
@@ -564,12 +564,14 @@ static void vmballoon_pop(struct vmballoon *b)
                }
        }
 
-       if ((b->capabilities & VMW_BALLOON_BATCHED_CMDS) != 0) {
-               if (b->batch_page)
-                       vunmap(b->batch_page);
+       if (b->batch_page) {
+               vunmap(b->batch_page);
+               b->batch_page = NULL;
+       }
 
-               if (b->page)
-                       __free_page(b->page);
+       if (b->page) {
+               __free_page(b->page);
+               b->page = NULL;
        }
 }
 
@@ -1044,7 +1046,7 @@ static void vmballoon_work(struct work_struct *work)
        if (b->slow_allocation_cycles > 0)
                b->slow_allocation_cycles--;
 
-       if (vmballoon_send_get_target(b, &target)) {
+       if (!b->reset_required && vmballoon_send_get_target(b, &target)) {
                /* update target, adjust size */
                b->target = target;
 
@@ -1076,8 +1078,10 @@ static int vmballoon_debug_show(struct seq_file *f, void *offset)
        /* format capabilities info */
        seq_printf(f,
                   "balloon capabilities:   %#4x\n"
-                  "used capabilities:      %#4lx\n",
-                  VMW_BALLOON_CAPABILITIES, b->capabilities);
+                  "used capabilities:      %#4lx\n"
+                  "is resetting:           %c\n",
+                  VMW_BALLOON_CAPABILITIES, b->capabilities,
+                  b->reset_required ? 'y' : 'n');
 
        /* format size info */
        seq_printf(f,
@@ -1196,35 +1200,14 @@ static int __init vmballoon_init(void)
 
        INIT_DELAYED_WORK(&balloon.dwork, vmballoon_work);
 
-       /*
-        * Start balloon.
-        */
-       if (!vmballoon_send_start(&balloon, VMW_BALLOON_CAPABILITIES)) {
-               pr_err("failed to send start command to the host\n");
-               return -EIO;
-       }
-
-       if ((balloon.capabilities & VMW_BALLOON_BATCHED_CMDS) != 0) {
-               balloon.ops = &vmballoon_batched_ops;
-               balloon.batch_max_pages = VMW_BALLOON_BATCH_MAX_PAGES;
-               if (!vmballoon_init_batching(&balloon)) {
-                       pr_err("failed to init batching\n");
-                       return -EIO;
-               }
-       } else if ((balloon.capabilities & VMW_BALLOON_BASIC_CMDS) != 0) {
-               balloon.ops = &vmballoon_basic_ops;
-               balloon.batch_max_pages = 1;
-       }
-
-       if (!vmballoon_send_guest_id(&balloon)) {
-               pr_err("failed to send guest ID to the host\n");
-               return -EIO;
-       }
-
        error = vmballoon_debugfs_init(&balloon);
        if (error)
                return error;
 
+       balloon.batch_page = NULL;
+       balloon.page = NULL;
+       balloon.reset_required = true;
+
        queue_delayed_work(system_freezable_wq, &balloon.dwork, 0);
 
        return 0;
@@ -1242,7 +1225,7 @@ static void __exit vmballoon_exit(void)
         * Reset connection before deallocating memory to avoid potential for
         * additional spurious resets from guest touching deallocated pages.
         */
-       vmballoon_send_start(&balloon, VMW_BALLOON_CAPABILITIES);
+       vmballoon_send_start(&balloon, 0);
        vmballoon_pop(&balloon);
 }
 module_exit(vmballoon_exit);