s390/qdio: cleanup chsc SSQD usage

Cleanup the function qdio_setup_get_ssqd. Fix some possible
memleaks and an unchecked allocation and create a wrapper
for SSQD in chsc.c .

Reviewed-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

4 files changed, 58 insertions, 43 deletions

diff --git a/drivers/s390/cio/chsc.c b/drivers/s390/cio/chsc.c
index 8ea7d9b2c671..d119d0d87e9b 100644
--- a/drivers/s390/cio/chsc.c
+++ b/drivers/s390/cio/chsc.c
@@ -144,6 +144,29 @@ out:
         return ret;
 }
 
+/**
+ * chsc_ssqd() - store subchannel QDIO data (SSQD)
+ * @schid: id of the subchannel on which SSQD is performed
+ * @ssqd: request and response block for SSQD
+ *
+ * Returns 0 on success.
+ */
+int chsc_ssqd(struct subchannel_id schid, struct chsc_ssqd_area *ssqd)
+{
+        memset(ssqd, 0, sizeof(*ssqd));
+        ssqd->request.length = 0x0010;
+        ssqd->request.code = 0x0024;
+        ssqd->first_sch = schid.sch_no;
+        ssqd->last_sch = schid.sch_no;
+        ssqd->ssid = schid.ssid;
+
+        if (chsc(ssqd))
+                return -EIO;
+
+        return chsc_error_from_response(ssqd->response.code);
+}
+EXPORT_SYMBOL_GPL(chsc_ssqd);
+
 static int s390_subchannel_remove_chpid(struct subchannel *sch, void *data)
 {
         spin_lock_irq(sch->lock);
diff --git a/drivers/s390/cio/chsc.h b/drivers/s390/cio/chsc.h
index 62d096f11e65..2b88e74e6b65 100644
--- a/drivers/s390/cio/chsc.h
+++ b/drivers/s390/cio/chsc.h
@@ -7,6 +7,7 @@
 #include <asm/chpid.h>
 #include <asm/chsc.h>
 #include <asm/schid.h>
+#include <asm/qdio.h>
 
 #define CHSC_SDA_OC_MSS   0x2
 
@@ -72,6 +73,20 @@ struct chsc_ssd_info {
         u16 fla[8];
 };
 
+struct chsc_ssqd_area {
+        struct chsc_header request;
+        u16:10;
+        u8 ssid:2;
+        u8 fmt:4;
+        u16 first_sch;
+        u16:16;
+        u16 last_sch;
+        u32:32;
+        struct chsc_header response;
+        u32:32;
+        struct qdio_ssqd_desc qdio_ssqd;
+} __packed;
+
 struct chsc_scpd {
         struct chsc_header request;
         u32:2;
@@ -111,7 +126,7 @@ int chsc_determine_fmt1_channel_path_desc(struct chp_id chpid,
 void chsc_chp_online(struct chp_id chpid);
 void chsc_chp_offline(struct chp_id chpid);
 int chsc_get_channel_measurement_chars(struct channel_path *chp);
-
+int chsc_ssqd(struct subchannel_id schid, struct chsc_ssqd_area *ssqd);
 int chsc_error_from_response(int response);
 
 int chsc_siosl(struct subchannel_id schid);
diff --git a/drivers/s390/cio/qdio.h b/drivers/s390/cio/qdio.h
index 5132554d7917..b8bda2175b6c 100644
--- a/drivers/s390/cio/qdio.h
+++ b/drivers/s390/cio/qdio.h
@@ -140,20 +140,6 @@ struct siga_flag {
         u8:3;
 } __attribute__ ((packed));
 
-struct chsc_ssqd_area {
-        struct chsc_header request;
-        u16:10;
-        u8 ssid:2;
-        u8 fmt:4;
-        u16 first_sch;
-        u16:16;
-        u16 last_sch;
-        u32:32;
-        struct chsc_header response;
-        u32:32;
-        struct qdio_ssqd_desc qdio_ssqd;
-} __attribute__ ((packed));
-
 struct scssc_area {
         struct chsc_header request;
         u16 operation_code;
diff --git a/drivers/s390/cio/qdio_setup.c b/drivers/s390/cio/qdio_setup.c
index 16ecd35b8e51..f5f4a91fab44 100644
--- a/drivers/s390/cio/qdio_setup.c
+++ b/drivers/s390/cio/qdio_setup.c
@@ -254,40 +254,31 @@ int qdio_setup_get_ssqd(struct qdio_irq *irq_ptr,
         int rc;
 
         DBF_EVENT("getssqd:%4x", schid->sch_no);
-        if (irq_ptr != NULL)
-                ssqd = (struct chsc_ssqd_area *)irq_ptr->chsc_page;
-        else
+        if (!irq_ptr) {
                 ssqd = (struct chsc_ssqd_area *)__get_free_page(GFP_KERNEL);
-        memset(ssqd, 0, PAGE_SIZE);
-
-        ssqd->request = (struct chsc_header) {
-                .length = 0x0010,
-                .code   = 0x0024,
-        };
-        ssqd->first_sch = schid->sch_no;
-        ssqd->last_sch = schid->sch_no;
-        ssqd->ssid = schid->ssid;
-
-        if (chsc(ssqd))
-                return -EIO;
-        rc = chsc_error_from_response(ssqd->response.code);
+                if (!ssqd)
+                        return -ENOMEM;
+        } else {
+                ssqd = (struct chsc_ssqd_area *)irq_ptr->chsc_page;
+        }
+
+        rc = chsc_ssqd(*schid, ssqd);
         if (rc)
-                return rc;
+                goto out;
 
         if (!(ssqd->qdio_ssqd.flags & CHSC_FLAG_QDIO_CAPABILITY) ||
             !(ssqd->qdio_ssqd.flags & CHSC_FLAG_VALIDITY) ||
             (ssqd->qdio_ssqd.sch != schid->sch_no))
-                return -EINVAL;
-
-        if (irq_ptr != NULL)
-                memcpy(&irq_ptr->ssqd_desc, &ssqd->qdio_ssqd,
-                       sizeof(struct qdio_ssqd_desc));
-        else {
-                memcpy(data, &ssqd->qdio_ssqd,
-                       sizeof(struct qdio_ssqd_desc));
+                rc = -EINVAL;
+
+        if (!rc)
+                memcpy(data, &ssqd->qdio_ssqd, sizeof(*data));
+
+out:
+        if (!irq_ptr)
                 free_page((unsigned long)ssqd);
-        }
-        return 0;
+
+        return rc;
 }
 
 void qdio_setup_ssqd_info(struct qdio_irq *irq_ptr)
@@ -295,7 +286,7 @@ void qdio_setup_ssqd_info(struct qdio_irq *irq_ptr)
         unsigned char qdioac;
         int rc;
 
-        rc = qdio_setup_get_ssqd(irq_ptr, &irq_ptr->schid, NULL);
+        rc = qdio_setup_get_ssqd(irq_ptr, &irq_ptr->schid, &irq_ptr->ssqd_desc);
         if (rc) {
                 DBF_ERROR("%4x ssqd ERR", irq_ptr->schid.sch_no);
                 DBF_ERROR("rc:%x", rc);