From 8020177f1c40da2a9ca09fa20dc90eda65739671 Mon Sep 17 00:00:00 2001

From: Matthew Rosato <mjrosato@linux.ibm.com>

Date: Fri, 2 Sep 2022 13:27:31 -0400

Subject: [PATCH 06/42] s390x/pci: add routine to get host function handle from

 CLP info

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RH-Author: Cédric Le Goater <clg@redhat.com>

RH-MergeRequest: 226: s390: Enhanced Interpretation for PCI Functions and Secure Execution guest dump

RH-Bugzilla: 1664378 2043909

RH-Acked-by: Thomas Huth <thuth@redhat.com>

RH-Acked-by: Cornelia Huck <cohuck@redhat.com>

RH-Acked-by: Jon Maloy <jmaloy@redhat.com>

RH-Commit: [6/41] 8ab652cf4095e61f5f55726d41111de227d452e7

In order to interface with the underlying host zPCI device, we need

to know its function handle. Add a routine to grab this from the

vfio CLP capabilities chain.

Signed-off-by: Matthew Rosato <mjrosato@linux.ibm.com>

Reviewed-by: Pierre Morel <pmorel@linux.ibm.com>

Message-Id: <20220902172737.170349-3-mjrosato@linux.ibm.com>

[thuth: Replace free(info) with g_free(info)]

Signed-off-by: Thomas Huth <thuth@redhat.com>

(cherry picked from commit 21fa15298d88db2050a713cdf79c10cb0e09146f)

Signed-off-by: Cédric Le Goater <clg@redhat.com>

---

 hw/s390x/s390-pci-vfio.c         | 83 ++++++++++++++++++++++++++------

 include/hw/s390x/s390-pci-vfio.h |  5 ++

 2 files changed, 72 insertions(+), 16 deletions(-)

diff --git a/hw/s390x/s390-pci-vfio.c b/hw/s390x/s390-pci-vfio.c

index 6f80a47e29..08bcc55e85 100644

--- a/hw/s390x/s390-pci-vfio.c

+++ b/hw/s390x/s390-pci-vfio.c

@@ -124,6 +124,27 @@ static void s390_pci_read_base(S390PCIBusDevice *pbdev,

     pbdev->zpci_fn.pft = 0;

 }

+static bool get_host_fh(S390PCIBusDevice *pbdev, struct vfio_device_info *info,

+                        uint32_t *fh)

+{

+    struct vfio_info_cap_header *hdr;

+    struct vfio_device_info_cap_zpci_base *cap;

+    VFIOPCIDevice *vpci = container_of(pbdev->pdev, VFIOPCIDevice, pdev);

+

+    hdr = vfio_get_device_info_cap(info, VFIO_DEVICE_INFO_CAP_ZPCI_BASE);

+

+    /* Can only get the host fh with version 2 or greater */

+    if (hdr == NULL || hdr->version < 2) {

+        trace_s390_pci_clp_cap(vpci->vbasedev.name,

+                               VFIO_DEVICE_INFO_CAP_ZPCI_BASE);

+        return false;

+    }

+    cap = (void *) hdr;

+

+    *fh = cap->fh;

+    return true;

+}

+

 static void s390_pci_read_group(S390PCIBusDevice *pbdev,

                                 struct vfio_device_info *info)

 {

@@ -217,25 +238,13 @@ static void s390_pci_read_pfip(S390PCIBusDevice *pbdev,

     memcpy(pbdev->zpci_fn.pfip, cap->pfip, CLP_PFIP_NR_SEGMENTS);

 }

-/*

- * This function will issue the VFIO_DEVICE_GET_INFO ioctl and look for

- * capabilities that contain information about CLP features provided by the

- * underlying host.

- * On entry, defaults have already been placed into the guest CLP response

- * buffers.  On exit, defaults will have been overwritten for any CLP features

- * found in the capability chain; defaults will remain for any CLP features not

- * found in the chain.

- */

-void s390_pci_get_clp_info(S390PCIBusDevice *pbdev)

+static struct vfio_device_info *get_device_info(S390PCIBusDevice *pbdev,

+                                                uint32_t argsz)

 {

-    g_autofree struct vfio_device_info *info = NULL;

+    struct vfio_device_info *info = g_malloc0(argsz);

     VFIOPCIDevice *vfio_pci;

-    uint32_t argsz;

     int fd;

-    argsz = sizeof(*info);

-    info = g_malloc0(argsz);

-

     vfio_pci = container_of(pbdev->pdev, VFIOPCIDevice, pdev);

     fd = vfio_pci->vbasedev.fd;

@@ -250,7 +259,8 @@ retry:

     if (ioctl(fd, VFIO_DEVICE_GET_INFO, info)) {

         trace_s390_pci_clp_dev_info(vfio_pci->vbasedev.name);

-        return;

+        g_free(info);

+        return NULL;

     }

     if (info->argsz > argsz) {

@@ -259,6 +269,47 @@ retry:

         goto retry;

     }

+    return info;

+}

+

+/*

+ * Get the host function handle from the vfio CLP capabilities chain.  Returns

+ * true if a fh value was placed into the provided buffer.  Returns false

+ * if a fh could not be obtained (ioctl failed or capabilitiy version does

+ * not include the fh)

+ */

+bool s390_pci_get_host_fh(S390PCIBusDevice *pbdev, uint32_t *fh)

+{

+    g_autofree struct vfio_device_info *info = NULL;

+

+    assert(fh);

+

+    info = get_device_info(pbdev, sizeof(*info));

+    if (!info) {

+        return false;

+    }

+

+    return get_host_fh(pbdev, info, fh);

+}

+

+/*

+ * This function will issue the VFIO_DEVICE_GET_INFO ioctl and look for

+ * capabilities that contain information about CLP features provided by the

+ * underlying host.

+ * On entry, defaults have already been placed into the guest CLP response

+ * buffers.  On exit, defaults will have been overwritten for any CLP features

+ * found in the capability chain; defaults will remain for any CLP features not

+ * found in the chain.

+ */

+void s390_pci_get_clp_info(S390PCIBusDevice *pbdev)

+{

+    g_autofree struct vfio_device_info *info = NULL;

+

+    info = get_device_info(pbdev, sizeof(*info));

+    if (!info) {

+        return;

+    }

+

     /*

      * Find the CLP features provided and fill in the guest CLP responses.

      * Always call s390_pci_read_base first as information from this could

diff --git a/include/hw/s390x/s390-pci-vfio.h b/include/hw/s390x/s390-pci-vfio.h

index ff708aef50..ae1b126ff7 100644

--- a/include/hw/s390x/s390-pci-vfio.h

+++ b/include/hw/s390x/s390-pci-vfio.h

@@ -20,6 +20,7 @@ bool s390_pci_update_dma_avail(int fd, unsigned int *avail);

 S390PCIDMACount *s390_pci_start_dma_count(S390pciState *s,

                                           S390PCIBusDevice *pbdev);

 void s390_pci_end_dma_count(S390pciState *s, S390PCIDMACount *cnt);

+bool s390_pci_get_host_fh(S390PCIBusDevice *pbdev, uint32_t *fh);

 void s390_pci_get_clp_info(S390PCIBusDevice *pbdev);

 #else

 static inline bool s390_pci_update_dma_avail(int fd, unsigned int *avail)

@@ -33,6 +34,10 @@ static inline S390PCIDMACount *s390_pci_start_dma_count(S390pciState *s,

 }

 static inline void s390_pci_end_dma_count(S390pciState *s,

                                           S390PCIDMACount *cnt) { }

+static inline bool s390_pci_get_host_fh(S390PCIBusDevice *pbdev, uint32_t *fh)

+{

+    return false;

+}

 static inline void s390_pci_get_clp_info(S390PCIBusDevice *pbdev) { }

 #endif

-- 

2.37.3