diff options
Diffstat (limited to 'drivers/lguest/hypercalls.c')
| -rw-r--r-- | drivers/lguest/hypercalls.c | 21 |
1 files changed, 13 insertions, 8 deletions
diff --git a/drivers/lguest/hypercalls.c b/drivers/lguest/hypercalls.c index 7a5299f9679d..db6caace3b9c 100644 --- a/drivers/lguest/hypercalls.c +++ b/drivers/lguest/hypercalls.c @@ -64,14 +64,6 @@ static void do_hcall(struct lguest *lg, struct lguest_regs *regs) else guest_pagetable_flush_user(lg); break; - case LHCALL_GET_WALLCLOCK: { - /* The Guest wants to know the real time in seconds since 1970, - * in good Unix tradition. */ - struct timespec ts; - ktime_get_real_ts(&ts); - regs->eax = ts.tv_sec; - break; - } case LHCALL_BIND_DMA: /* BIND_DMA really wants four arguments, but it's the only call * which does. So the Guest packs the number of buffers and @@ -235,6 +227,9 @@ static void initialize(struct lguest *lg) || put_user(lg->guestid, &lg->lguest_data->guestid)) kill_guest(lg, "bad guest page %p", lg->lguest_data); + /* We write the current time into the Guest's data page once now. */ + write_timestamp(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) @@ -293,3 +288,13 @@ void do_hypercalls(struct lguest *lg) clear_hcall(lg); } } + +/* This routine supplies the Guest with time: it's used for wallclock time at + * initial boot and as a rough time source if the TSC isn't available. */ +void write_timestamp(struct lguest *lg) +{ + struct timespec now; + ktime_get_real_ts(&now); + if (put_user(now, &lg->lguest_data->time)) + kill_guest(lg, "Writing timestamp"); +} |