> -----Original Message----- > From: Greg KH [mailto:gregkh@xxxxxxxxxxxxxxxxxxx] > Sent: Monday, December 14, 2015 7:08 PM > To: KY Srinivasan <kys@xxxxxxxxxxxxx> > Cc: linux-kernel@xxxxxxxxxxxxxxx; devel@xxxxxxxxxxxxxxxxxxxxxx; > olaf@xxxxxxxxx; apw@xxxxxxxxxxxxx; vkuznets@xxxxxxxxxx; > jasowang@xxxxxxxxxx; Jake Oshins <jakeo@xxxxxxxxxxxxx> > Subject: Re: [PATCH RESEND 09/27] drivers:hv: Export the API to invoke a > hypercall on Hyper-V > > On Mon, Dec 14, 2015 at 04:01:40PM -0800, K. Y. Srinivasan wrote: > > From: Jake Oshins <jakeo@xxxxxxxxxxxxx> > > > > This patch exposes the function that hv_vmbus.ko uses to make hypercalls. > This > > is necessary for retargeting an interrupt when it is given a new affinity. > > > > Since we are exporting this API, rename the API as it will be visible outside > > the hv.c file. > > > > Signed-off-by: Jake Oshins <jakeo@xxxxxxxxxxxxx> > > Signed-off-by: K. Y. Srinivasan <kys@xxxxxxxxxxxxx> > > --- > > drivers/hv/hv.c | 20 ++++++++++---------- > > drivers/hv/hyperv_vmbus.h | 2 +- > > include/linux/hyperv.h | 1 + > > 3 files changed, 12 insertions(+), 11 deletions(-) > > > > diff --git a/drivers/hv/hv.c b/drivers/hv/hv.c > > index 6341be8..7a06933 100644 > > --- a/drivers/hv/hv.c > > +++ b/drivers/hv/hv.c > > @@ -89,9 +89,9 @@ static int query_hypervisor_info(void) > > } > > > > /* > > - * do_hypercall- Invoke the specified hypercall > > + * hv_do_hypercall- Invoke the specified hypercall > > */ > > -static u64 do_hypercall(u64 control, void *input, void *output) > > +u64 hv_do_hypercall(u64 control, void *input, void *output) > > { > > u64 input_address = (input) ? virt_to_phys(input) : 0; > > u64 output_address = (output) ? virt_to_phys(output) : 0; > > @@ -132,6 +132,7 @@ static u64 do_hypercall(u64 control, void *input, > void *output) > > return hv_status_lo | ((u64)hv_status_hi << 32); > > #endif /* !x86_64 */ > > } > > +EXPORT_SYMBOL_GPL(hv_do_hypercall); > > > > #ifdef CONFIG_X86_64 > > static cycle_t read_hv_clock_tsc(struct clocksource *arg) > > @@ -315,7 +316,7 @@ int hv_post_message(union hv_connection_id > connection_id, > > { > > > > struct hv_input_post_message *aligned_msg; > > - u16 status; > > + u64 status; > > > > if (payload_size > HV_MESSAGE_PAYLOAD_BYTE_COUNT) > > return -EMSGSIZE; > > @@ -329,11 +330,10 @@ int hv_post_message(union hv_connection_id > connection_id, > > aligned_msg->payload_size = payload_size; > > memcpy((void *)aligned_msg->payload, payload, payload_size); > > > > - status = do_hypercall(HVCALL_POST_MESSAGE, aligned_msg, NULL) > > - & 0xFFFF; > > + status = hv_do_hypercall(HVCALL_POST_MESSAGE, aligned_msg, > NULL); > > > > put_cpu(); > > - return status; > > + return status & 0xFFFF; > > } > > > > > > @@ -343,13 +343,13 @@ int hv_post_message(union hv_connection_id > connection_id, > > * > > * This involves a hypercall. > > */ > > -u16 hv_signal_event(void *con_id) > > +int hv_signal_event(void *con_id) > > { > > - u16 status; > > + u64 status; > > > > - status = (do_hypercall(HVCALL_SIGNAL_EVENT, con_id, NULL) & > 0xFFFF); > > + status = hv_do_hypercall(HVCALL_SIGNAL_EVENT, con_id, NULL); > > > > - return status; > > + return status & 0xFFFF; > > This "feels" odd, as the return value isn't the traditional 0 or -ERROR, > right? Why are you masking off the top bits? > > And, no one ever does anything with the return value of > hv_signal_event(), so why have it return anything anyway? > > I'll take this, but please fix up the area, it's messy... Thanks Greg. Will do. K. Y > > greg k-h _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
