[PATCH v4 12/32] s390/pci: get SHM information from list pci

[Matthew Rosato <mjrosato@xxxxxxxxxxxxx>]

KVM will need information on the special handle mask used to indicate
emulated devices.  In order to obtain this, a new type of list pci call
must be made to gather the information.  Extend clp_list_pci_req to
also fetch the model-dependent-data field that holds this mask.

Reviewed-by: Niklas Schnelle <schnelle@xxxxxxxxxxxxx>
Acked-by: Pierre Morel <pmorel@xxxxxxxxxxxxx>
Signed-off-by: Matthew Rosato <mjrosato@xxxxxxxxxxxxx>
---
 arch/s390/include/asm/pci.h     |  1 +
 arch/s390/include/asm/pci_clp.h |  2 +-
 arch/s390/pci/pci_clp.c         | 25 ++++++++++++++++++++++---
 3 files changed, 24 insertions(+), 4 deletions(-)

diff --git a/arch/s390/include/asm/pci.h b/arch/s390/include/asm/pci.h
index 3c0b9986dcdc..e8a3fd5bc169 100644
--- a/arch/s390/include/asm/pci.h
+++ b/arch/s390/include/asm/pci.h
@@ -227,6 +227,7 @@ int clp_enable_fh(struct zpci_dev *zdev, u32 *fh, u8 nr_dma_as);
 int clp_disable_fh(struct zpci_dev *zdev, u32 *fh);
 int clp_get_state(u32 fid, enum zpci_state *state);
 int clp_refresh_fh(u32 fid, u32 *fh);
+int zpci_get_mdd(u32 *mdd);
 
 /* UID */
 void update_uid_checking(bool new);
diff --git a/arch/s390/include/asm/pci_clp.h b/arch/s390/include/asm/pci_clp.h
index d6189ed14f84..dc2041e97de4 100644
--- a/arch/s390/include/asm/pci_clp.h
+++ b/arch/s390/include/asm/pci_clp.h
@@ -76,7 +76,7 @@ struct clp_req_list_pci {
 struct clp_rsp_list_pci {
 	struct clp_rsp_hdr hdr;
 	u64 resume_token;
-	u32 reserved2;
+	u32 mdd;
 	u16 max_fn;
 	u8			: 7;
 	u8 uid_checking		: 1;
diff --git a/arch/s390/pci/pci_clp.c b/arch/s390/pci/pci_clp.c
index dc733b58e74f..7477956be632 100644
--- a/arch/s390/pci/pci_clp.c
+++ b/arch/s390/pci/pci_clp.c
@@ -328,7 +328,7 @@ int clp_disable_fh(struct zpci_dev *zdev, u32 *fh)
 }
 
 static int clp_list_pci_req(struct clp_req_rsp_list_pci *rrb,
-			    u64 *resume_token, int *nentries)
+			    u64 *resume_token, int *nentries, u32 *mdd)
 {
 	int rc;
 
@@ -354,6 +354,8 @@ static int clp_list_pci_req(struct clp_req_rsp_list_pci *rrb,
 	*nentries = (rrb->response.hdr.len - LIST_PCI_HDR_LEN) /
 		rrb->response.entry_size;
 	*resume_token = rrb->response.resume_token;
+	if (mdd)
+		*mdd = rrb->response.mdd;
 
 	return rc;
 }
@@ -365,7 +367,7 @@ static int clp_list_pci(struct clp_req_rsp_list_pci *rrb, void *data,
 	int nentries, i, rc;
 
 	do {
-		rc = clp_list_pci_req(rrb, &resume_token, &nentries);
+		rc = clp_list_pci_req(rrb, &resume_token, &nentries, NULL);
 		if (rc)
 			return rc;
 		for (i = 0; i < nentries; i++)
@@ -383,7 +385,7 @@ static int clp_find_pci(struct clp_req_rsp_list_pci *rrb, u32 fid,
 	int nentries, i, rc;
 
 	do {
-		rc = clp_list_pci_req(rrb, &resume_token, &nentries);
+		rc = clp_list_pci_req(rrb, &resume_token, &nentries, NULL);
 		if (rc)
 			return rc;
 		fh_list = rrb->response.fh_list;
@@ -468,6 +470,23 @@ int clp_get_state(u32 fid, enum zpci_state *state)
 	return rc;
 }
 
+int zpci_get_mdd(u32 *mdd)
+{
+	struct clp_req_rsp_list_pci *rrb;
+	u64 resume_token = 0;
+	int nentries, rc;
+
+	rrb = clp_alloc_block(GFP_KERNEL);
+	if (!rrb)
+		return -ENOMEM;
+
+	rc = clp_list_pci_req(rrb, &resume_token, &nentries, mdd);
+
+	clp_free_block(rrb);
+	return rc;
+}
+EXPORT_SYMBOL_GPL(zpci_get_mdd);
+
 static int clp_base_slpc(struct clp_req *req, struct clp_req_rsp_slpc *lpcb)
 {
 	unsigned long limit = PAGE_SIZE - sizeof(lpcb->request);
-- 
2.27.0