Commit 0b0d1173 authored by Claudio Imbrenda's avatar Claudio Imbrenda Committed by Martin Schwidefsky
Browse files

s390/sclp: 32 bit event mask compatibility mode 



Qemu before version 2.11 does not implement the architecture correctly,
and does not allow for a mask size of size different than 4.

This patch introduces a compatibility mode for such systems, forcing
the mask sizes to 4.

Since the mask size is currently still 4 anyway, this patch should have
no impact whatsoever by itself, but it will be needed when the mask size
is increased to 64 bits in the next patch.

Reviewed-by: default avatarHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: default avatarClaudio Imbrenda <imbrenda@linux.vnet.ibm.com>
Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
parent b8435635

drivers/s390/char/sclp.c

+16 −7
Original line number Diff line number Diff line
@@ -765,6 +765,9 @@ __sclp_make_init_req(sccb_mask_t receive_mask, sccb_mask_t send_mask) 
	sclp_init_req.callback_data = NULL;

	sclp_init_req.sccb = sccb;

	sccb->header.length = sizeof(*sccb);

	if (sclp_mask_compat_mode)

		sccb->mask_length = SCLP_MASK_SIZE_COMPAT;

	else

		sccb->mask_length = sizeof(sccb_mask_t);

	sccb_set_recv_mask(sccb, receive_mask);

	sccb_set_send_mask(sccb, send_mask);
@@ -977,12 +980,18 @@ sclp_check_interface(void) 
		irq_subclass_unregister(IRQ_SUBCLASS_SERVICE_SIGNAL);

		spin_lock_irqsave(&sclp_lock, flags);

		del_timer(&sclp_request_timer);

		if (sclp_init_req.status == SCLP_REQ_DONE &&

		    sccb->header.response_code == 0x20) {

		rc = -EBUSY;

		if (sclp_init_req.status == SCLP_REQ_DONE) {

			if (sccb->header.response_code == 0x20) {

				rc = 0;

				break;

		} else

			rc = -EBUSY;

			} else if (sccb->header.response_code == 0x74f0) {

				if (!sclp_mask_compat_mode) {

					sclp_mask_compat_mode = true;

					retry = 0;

				}

			}

		}

	}

	unregister_external_irq(EXT_IRQ_SERVICE_SIG, sclp_check_handler);

	spin_unlock_irqrestore(&sclp_lock, flags);

drivers/s390/char/sclp.h

+3 −0
Original line number Diff line number Diff line
@@ -109,6 +109,8 @@ struct init_sccb { 
	 */

} __attribute__((packed));



#define SCLP_MASK_SIZE_COMPAT 4



static inline sccb_mask_t sccb_get_mask(u8 *masks, size_t len, int i)

{

	sccb_mask_t res = 0;
@@ -262,6 +264,7 @@ extern int sclp_init_state; 
extern int sclp_console_pages;

extern int sclp_console_drop;

extern unsigned long sclp_console_full;

extern bool sclp_mask_compat_mode;



extern char sclp_early_sccb[PAGE_SIZE];

drivers/s390/char/sclp_early_core.c

+14 −1
Original line number Diff line number Diff line
@@ -14,6 +14,11 @@ 


char sclp_early_sccb[PAGE_SIZE] __aligned(PAGE_SIZE) __section(.data);

int sclp_init_state __section(.data) = sclp_init_state_uninitialized;

/*

 * Used to keep track of the size of the event masks. Qemu until version 2.11

 * only supports 4 and needs a workaround.

 */

bool sclp_mask_compat_mode;



void sclp_early_wait_irq(void)

{
@@ -145,13 +150,21 @@ int sclp_early_set_event_mask(struct init_sccb *sccb, 
			      sccb_mask_t receive_mask,

			      sccb_mask_t send_mask)

{

retry:

	memset(sccb, 0, sizeof(*sccb));

	sccb->header.length = sizeof(*sccb);

	if (sclp_mask_compat_mode)

		sccb->mask_length = SCLP_MASK_SIZE_COMPAT;

	else

		sccb->mask_length = sizeof(sccb_mask_t);

	sccb_set_recv_mask(sccb, receive_mask);

	sccb_set_send_mask(sccb, send_mask);

	if (sclp_early_cmd(SCLP_CMDW_WRITE_EVENT_MASK, sccb))

		return -EIO;

	if ((sccb->header.response_code == 0x74f0) && !sclp_mask_compat_mode) {

		sclp_mask_compat_mode = true;

		goto retry;

	}

	if (sccb->header.response_code != 0x20)

		return -EIO;

	return 0;

CRA Git | Maintained and supported by SUSTech CRA and CCSE