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authorSebastian Ott <sebott@linux.vnet.ibm.com>2010-10-25 16:10:30 +0200
committerMartin Schwidefsky <sky@mschwide.boeblingen.de.ibm.com>2010-10-25 16:10:18 +0200
commit906c9768c7750ce76b85597174b9c3599a6ca9f6 (patch)
tree8676732f1a6bf8f83575a0d7c69048d76097ddde /drivers/s390/cio/chsc_sch.c
parent34196f82b16749e119db5572271944c4add0a9aa (diff)
[S390] chsc: use the global page to determine the chp desriptor
chsc_determine_channel_path_desc is called by a wrapper who allocates a response struct. The response data is then memcpy'ed to this response struct by chsc_determine_channel_path_desc. Change chsc_determine_base_channel_path_desc to use the global chsc_page and deliver it to the function doing the actual chsc call. The channel path desriptor is then directly read from the response data. As a result we get rid of the additional allocation for the response struct. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Diffstat (limited to 'drivers/s390/cio/chsc_sch.c')
-rw-r--r--drivers/s390/cio/chsc_sch.c12
1 files changed, 9 insertions, 3 deletions
diff --git a/drivers/s390/cio/chsc_sch.c b/drivers/s390/cio/chsc_sch.c
index f2b77e7bfc6..3c3f3ffe217 100644
--- a/drivers/s390/cio/chsc_sch.c
+++ b/drivers/s390/cio/chsc_sch.c
@@ -688,25 +688,31 @@ out_free:
static int chsc_ioctl_chpd(void __user *user_chpd)
{
+ struct chsc_scpd *scpd_area;
struct chsc_cpd_info *chpd;
int ret;
chpd = kzalloc(sizeof(*chpd), GFP_KERNEL);
- if (!chpd)
- return -ENOMEM;
+ scpd_area = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
+ if (!scpd_area || !chpd) {
+ ret = -ENOMEM;
+ goto out_free;
+ }
if (copy_from_user(chpd, user_chpd, sizeof(*chpd))) {
ret = -EFAULT;
goto out_free;
}
ret = chsc_determine_channel_path_desc(chpd->chpid, chpd->fmt,
chpd->rfmt, chpd->c, chpd->m,
- &chpd->chpdb);
+ scpd_area);
if (ret)
goto out_free;
+ memcpy(&chpd->chpdb, &scpd_area->response, scpd_area->response.length);
if (copy_to_user(user_chpd, chpd, sizeof(*chpd)))
ret = -EFAULT;
out_free:
kfree(chpd);
+ free_page((unsigned long)scpd_area);
return ret;
}