From: Eric Farman <farman@linux.ibm.com>
To: Cornelia Huck <cohuck@redhat.com>, Farhan Ali <alifm@linux.ibm.com>
Cc: Halil Pasic <pasic@linux.ibm.com>,
linux-s390@vger.kernel.org, kvm@vger.kernel.org,
Eric Farman <farman@linux.ibm.com>
Subject: [RFC PATCH v1 4/5] vfio-ccw: Factor out the ccw0-to-ccw1 transition
Date: Tue, 18 Jun 2019 22:23:51 +0200 [thread overview]
Message-ID: <20190618202352.39702-5-farman@linux.ibm.com> (raw)
In-Reply-To: <20190618202352.39702-1-farman@linux.ibm.com>
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>
---
drivers/s390/cio/vfio_ccw_cp.c | 48 ++++++++++++++++++----------------
1 file 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)
--
2.17.1
next prev parent reply other threads:[~2019-06-18 20:24 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-06-18 20:23 [RFC PATCH v1 0/5] s390: more vfio-ccw code rework Eric Farman
2019-06-18 20:23 ` [RFC PATCH v1 1/5] vfio-ccw: Move guest_cp storage into common struct Eric Farman
2019-06-19 8:14 ` Cornelia Huck
2019-06-19 20:13 ` Farhan Ali
2019-06-19 20:53 ` Eric Farman
2019-06-19 21:12 ` Farhan Ali
2019-06-18 20:23 ` [RFC PATCH v1 2/5] vfio-ccw: Skip second copy of guest cp to host Eric Farman
2019-06-19 8:17 ` Cornelia Huck
2019-06-18 20:23 ` [RFC PATCH v1 3/5] vfio-ccw: Copy CCW data outside length calculation Eric Farman
2019-06-19 8:18 ` Cornelia Huck
2019-06-18 20:23 ` Eric Farman [this message]
2019-06-19 8:22 ` [RFC PATCH v1 4/5] vfio-ccw: Factor out the ccw0-to-ccw1 transition Cornelia Huck
2019-06-18 20:23 ` [RFC PATCH v1 5/5] vfio-ccw: Remove copy_ccw_from_iova() Eric Farman
2019-06-19 8:23 ` Cornelia Huck
2019-06-19 21:13 ` Farhan Ali
2019-06-19 8:25 ` [RFC PATCH v1 0/5] s390: more vfio-ccw code rework Cornelia Huck
2019-06-19 11:11 ` Eric Farman
2019-06-19 21:15 ` Farhan Ali
2019-06-21 12:25 ` Cornelia Huck
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