haraldwolff/qemu-patch-raspberry4
1
0
Fork 0
Code Issues Pull requests Packages Projects Releases Wiki Activity

s390/css: handle CCW_FLAG_SKIP

Browse source 
If a ccw has CCW_FLAG_SKIP set, and the command is of type
read, read backwards, or sense, no data should be written
to the guest for that command.

Reviewed-by: Eric Farman <farman@linux.ibm.com>
Message-Id: <20190516133327.11430-1-cohuck@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
This commit is contained in:
Cornelia Huck 2019-05-06 19:11:48 +02:00
parent 1e3f9c69a4
commit 85fa94e169
2 changed files with 19 additions and 4 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

22
hw/s390x/css.c
View file

@ -830,8 +830,12 @@ static int ccw_dstream_rw_noflags(CcwDataStream *cds, void *buff, int len,
if (op == CDS_OP_A) {
goto incr;
}
ret = address_space_rw(&address_space_memory, cds->cda,
MEMTXATTRS_UNSPECIFIED, buff, len, op);
if (!cds->do_skip) {
ret = address_space_rw(&address_space_memory, cds->cda,
MEMTXATTRS_UNSPECIFIED, buff, len, op);
} else {
ret = MEMTX_OK;
}
if (ret != MEMTX_OK) {
cds->flags |= CDS_F_STREAM_BROKEN;
return -EINVAL;
@ -928,8 +932,13 @@ static int ccw_dstream_rw_ida(CcwDataStream *cds, void *buff, int len,
do {
iter_len = MIN(len, cont_left);
if (op != CDS_OP_A) {
ret = address_space_rw(&address_space_memory, cds->cda,
MEMTXATTRS_UNSPECIFIED, buff, iter_len, op);
if (!cds->do_skip) {
ret = address_space_rw(&address_space_memory, cds->cda,
MEMTXATTRS_UNSPECIFIED, buff, iter_len,
op);
} else {
ret = MEMTX_OK;
}
if (ret != MEMTX_OK) {
/* assume inaccessible address */
ret = -EINVAL; /* channel program check */
@ -968,6 +977,11 @@ void ccw_dstream_init(CcwDataStream *cds, CCW1 const *ccw, ORB const *orb)
cds->count = ccw->count;
cds->cda_orig = ccw->cda;
/* skip is only effective for read, read backwards, or sense commands */
cds->do_skip = (ccw->flags & CCW_FLAG_SKIP) &&
((ccw->cmd_code & 0x0f) == CCW_CMD_BASIC_SENSE ||
(ccw->cmd_code & 0x03) == 0x02 /* read */ ||
(ccw->cmd_code & 0x0f) == 0x0c /* read backwards */);
ccw_dstream_rewind(cds);
if (!(cds->flags & CDS_F_IDA)) {
cds->op_handler = ccw_dstream_rw_noflags;

1
include/hw/s390x/css.h
View file

@ -97,6 +97,7 @@ typedef struct CcwDataStream {
int (*op_handler)(struct CcwDataStream *cds, void *buff, int len,
CcwDataStreamOp op);
hwaddr cda;
bool do_skip;
} CcwDataStream;
/*