diff options
| author | Eric Farman | 2019-06-18 22:23:51 +0200 |
|---|---|---|
| committer | Cornelia Huck | 2019-06-21 14:13:11 +0200 |
| commit | 7f8e89a8f2fdb58461b01bb33ed8a5aa8119bf17 (patch) | |
| tree | 71f1a034a700358c5e855f8b70ce69f4bfe6075e | |
| parent | ded563f31d0eb4de0bcb101b755cdf6f4ed805e4 (diff) | |
vfio-ccw: Factor out the ccw0-to-ccw1 transition
This is a really useful function, but it's buried in the
copy_ccw_from_iova() routine so that ccwchain_calc_length()
can just work with Format-1 CCWs while doing its counting.
But it means we're translating a full 2K of "CCWs" to Format-1,
when in reality there's probably far fewer in that space.
Let's factor it out, so maybe we can do something with it later.
Signed-off-by: Eric Farman <farman@linux.ibm.com>
Message-Id: <20190618202352.39702-5-farman@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Farhan Ali <alifm@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
| -rw-r--r-- | drivers/s390/cio/vfio_ccw_cp.c | 48 |
1 files changed, 25 insertions, 23 deletions
diff --git a/drivers/s390/cio/vfio_ccw_cp.c b/drivers/s390/cio/vfio_ccw_cp.c index a55f8d110920..9a8bf06281e0 100644 --- a/drivers/s390/cio/vfio_ccw_cp.c +++ b/drivers/s390/cio/vfio_ccw_cp.c @@ -161,6 +161,27 @@ static inline void pfn_array_idal_create_words( idaws[0] += pa->pa_iova & (PAGE_SIZE - 1); } +void convert_ccw0_to_ccw1(struct ccw1 *source, unsigned long len) +{ + struct ccw0 ccw0; + struct ccw1 *pccw1 = source; + int i; + + for (i = 0; i < len; i++) { + ccw0 = *(struct ccw0 *)pccw1; + if ((pccw1->cmd_code & 0x0f) == CCW_CMD_TIC) { + pccw1->cmd_code = CCW_CMD_TIC; + pccw1->flags = 0; + pccw1->count = 0; + } else { + pccw1->cmd_code = ccw0.cmd_code; + pccw1->flags = ccw0.flags; + pccw1->count = ccw0.count; + } + pccw1->cda = ccw0.cda; + pccw1++; + } +} /* * Within the domain (@mdev), copy @n bytes from a guest physical @@ -211,32 +232,9 @@ static long copy_ccw_from_iova(struct channel_program *cp, struct ccw1 *to, u64 iova, unsigned long len) { - struct ccw0 ccw0; - struct ccw1 *pccw1; int ret; - int i; ret = copy_from_iova(cp->mdev, to, iova, len * sizeof(struct ccw1)); - if (ret) - return ret; - - if (!cp->orb.cmd.fmt) { - pccw1 = to; - for (i = 0; i < len; i++) { - ccw0 = *(struct ccw0 *)pccw1; - if ((pccw1->cmd_code & 0x0f) == CCW_CMD_TIC) { - pccw1->cmd_code = CCW_CMD_TIC; - pccw1->flags = 0; - pccw1->count = 0; - } else { - pccw1->cmd_code = ccw0.cmd_code; - pccw1->flags = ccw0.flags; - pccw1->count = ccw0.count; - } - pccw1->cda = ccw0.cda; - pccw1++; - } - } return ret; } @@ -441,6 +439,10 @@ static int ccwchain_handle_ccw(u32 cda, struct channel_program *cp) if (len) return len; + /* Convert any Format-0 CCWs to Format-1 */ + if (!cp->orb.cmd.fmt) + convert_ccw0_to_ccw1(cp->guest_cp, len); + /* Count the CCWs in the current chain */ len = ccwchain_calc_length(cda, cp); if (len < 0) |