lguest: documentation update

[deliverable/linux.git] / drivers / lguest / hypercalls.c

diff --git a/drivers/lguest/hypercalls.c b/drivers/lguest/hypercalls.c
index 9d5184c7c14afc83652843f6d3cfe1534a3dcf7e..b478affe8f91331733a288fa039fce50012e8409 100644 (file)
--- a/drivers/lguest/hypercalls.c
+++ b/drivers/lguest/hypercalls.c
@@ -90,6 +90,7 @@ static void do_hcall(struct lguest *lg, struct hcall_args *args)
                lg->pending_notify = args->arg1;
                break;
        default:
+               /* It should be an architecture-specific hypercall. */
                if (lguest_arch_do_hcall(lg, args))
                        kill_guest(lg, "Bad hypercall %li\n", args->arg0);
        }
@@ -157,7 +158,6 @@ static void do_async_hcalls(struct lguest *lg)
  * Guest makes a hypercall, we end up here to set things up: */
 static void initialize(struct lguest *lg)
 {
-
        /* You can't do anything until you're initialized.  The Guest knows the
         * rules, so we're unforgiving here. */
        if (lg->hcall->arg0 != LHCALL_LGUEST_INIT) {
@@ -174,7 +174,8 @@ static void initialize(struct lguest *lg)
            || get_user(lg->noirq_end, &lg->lguest_data->noirq_end))
                kill_guest(lg, "bad guest page %p", lg->lguest_data);
 
-       /* We write the current time into the Guest's data page once now. */
+       /* We write the current time into the Guest's data page once so it can
+        * set its clock. */
        write_timestamp(lg);
 
        /* page_tables.c will also do some setup. */
@@ -182,8 +183,8 @@ static void initialize(struct lguest *lg)
 
        /* This is the one case where the above accesses might have been the
         * first write to a Guest page.  This may have caused a copy-on-write
-        * fault, but the Guest might be referring to the old (read-only)
-        * page. */
+        * fault, but the old page might be (read-only) in the Guest
+        * pagetable. */
        guest_pagetable_clear_all(lg);
 }
 
@@ -220,7 +221,7 @@ void do_hypercalls(struct lguest *lg)
                 * Normally it doesn't matter: the Guest will run again and
                 * update the trap number before we come back here.
                 *
-                * However, if we are signalled or the Guest sends DMA to the
+                * However, if we are signalled or the Guest sends I/O to the
                 * Launcher, the run_guest() loop will exit without running the
                 * Guest.  When it comes back it would try to re-run the
                 * hypercall. */