1 /* 2 * s390 vfio-pci interfaces 3 * 4 * Copyright 2020 IBM Corp. 5 * Author(s): Matthew Rosato <mjrosato@linux.ibm.com> 6 * 7 * This work is licensed under the terms of the GNU GPL, version 2 or (at 8 * your option) any later version. See the COPYING file in the top-level 9 * directory. 10 */ 11 12 #include "qemu/osdep.h" 13 14 #include <sys/ioctl.h> 15 #include <linux/vfio.h> 16 #include <linux/vfio_zdev.h> 17 18 #include "trace.h" 19 #include "hw/s390x/s390-pci-bus.h" 20 #include "hw/s390x/s390-pci-clp.h" 21 #include "hw/s390x/s390-pci-vfio.h" 22 #include "hw/vfio/pci.h" 23 #include "hw/vfio/vfio-common.h" 24 25 /* 26 * Get the current DMA available count from vfio. Returns true if vfio is 27 * limiting DMA requests, false otherwise. The current available count read 28 * from vfio is returned in avail. 29 */ 30 bool s390_pci_update_dma_avail(int fd, unsigned int *avail) 31 { 32 uint32_t argsz = sizeof(struct vfio_iommu_type1_info); 33 g_autofree struct vfio_iommu_type1_info *info = g_malloc0(argsz); 34 35 assert(avail); 36 37 /* 38 * If the specified argsz is not large enough to contain all capabilities 39 * it will be updated upon return from the ioctl. Retry until we have 40 * a big enough buffer to hold the entire capability chain. 41 */ 42 retry: 43 info->argsz = argsz; 44 45 if (ioctl(fd, VFIO_IOMMU_GET_INFO, info)) { 46 return false; 47 } 48 49 if (info->argsz > argsz) { 50 argsz = info->argsz; 51 info = g_realloc(info, argsz); 52 goto retry; 53 } 54 55 /* If the capability exists, update with the current value */ 56 return vfio_get_info_dma_avail(info, avail); 57 } 58 59 S390PCIDMACount *s390_pci_start_dma_count(S390pciState *s, 60 S390PCIBusDevice *pbdev) 61 { 62 S390PCIDMACount *cnt; 63 uint32_t avail; 64 VFIOPCIDevice *vpdev = container_of(pbdev->pdev, VFIOPCIDevice, pdev); 65 int id; 66 67 assert(vpdev); 68 69 id = vpdev->vbasedev.group->container->fd; 70 71 if (!s390_pci_update_dma_avail(id, &avail)) { 72 return NULL; 73 } 74 75 QTAILQ_FOREACH(cnt, &s->zpci_dma_limit, link) { 76 if (cnt->id == id) { 77 cnt->users++; 78 return cnt; 79 } 80 } 81 82 cnt = g_new0(S390PCIDMACount, 1); 83 cnt->id = id; 84 cnt->users = 1; 85 cnt->avail = avail; 86 QTAILQ_INSERT_TAIL(&s->zpci_dma_limit, cnt, link); 87 return cnt; 88 } 89 90 void s390_pci_end_dma_count(S390pciState *s, S390PCIDMACount *cnt) 91 { 92 assert(cnt); 93 94 cnt->users--; 95 if (cnt->users == 0) { 96 QTAILQ_REMOVE(&s->zpci_dma_limit, cnt, link); 97 } 98 } 99 100 static void s390_pci_read_base(S390PCIBusDevice *pbdev, 101 struct vfio_device_info *info) 102 { 103 struct vfio_info_cap_header *hdr; 104 struct vfio_device_info_cap_zpci_base *cap; 105 VFIOPCIDevice *vpci = container_of(pbdev->pdev, VFIOPCIDevice, pdev); 106 107 hdr = vfio_get_device_info_cap(info, VFIO_DEVICE_INFO_CAP_ZPCI_BASE); 108 109 /* If capability not provided, just leave the defaults in place */ 110 if (hdr == NULL) { 111 trace_s390_pci_clp_cap(vpci->vbasedev.name, 112 VFIO_DEVICE_INFO_CAP_ZPCI_BASE); 113 return; 114 } 115 cap = (void *) hdr; 116 117 pbdev->zpci_fn.sdma = cap->start_dma; 118 pbdev->zpci_fn.edma = cap->end_dma; 119 pbdev->zpci_fn.pchid = cap->pchid; 120 pbdev->zpci_fn.vfn = cap->vfn; 121 pbdev->zpci_fn.pfgid = cap->gid; 122 /* The following values remain 0 until we support other FMB formats */ 123 pbdev->zpci_fn.fmbl = 0; 124 pbdev->zpci_fn.pft = 0; 125 } 126 127 static void s390_pci_read_group(S390PCIBusDevice *pbdev, 128 struct vfio_device_info *info) 129 { 130 struct vfio_info_cap_header *hdr; 131 struct vfio_device_info_cap_zpci_group *cap; 132 ClpRspQueryPciGrp *resgrp; 133 VFIOPCIDevice *vpci = container_of(pbdev->pdev, VFIOPCIDevice, pdev); 134 135 hdr = vfio_get_device_info_cap(info, VFIO_DEVICE_INFO_CAP_ZPCI_GROUP); 136 137 /* If capability not provided, just use the default group */ 138 if (hdr == NULL) { 139 trace_s390_pci_clp_cap(vpci->vbasedev.name, 140 VFIO_DEVICE_INFO_CAP_ZPCI_GROUP); 141 pbdev->zpci_fn.pfgid = ZPCI_DEFAULT_FN_GRP; 142 pbdev->pci_group = s390_group_find(ZPCI_DEFAULT_FN_GRP); 143 return; 144 } 145 cap = (void *) hdr; 146 147 /* See if the PCI group is already defined, create if not */ 148 pbdev->pci_group = s390_group_find(pbdev->zpci_fn.pfgid); 149 150 if (!pbdev->pci_group) { 151 pbdev->pci_group = s390_group_create(pbdev->zpci_fn.pfgid); 152 153 resgrp = &pbdev->pci_group->zpci_group; 154 if (cap->flags & VFIO_DEVICE_INFO_ZPCI_FLAG_REFRESH) { 155 resgrp->fr = 1; 156 } 157 resgrp->dasm = cap->dasm; 158 resgrp->msia = cap->msi_addr; 159 resgrp->mui = cap->mui; 160 resgrp->i = cap->noi; 161 resgrp->maxstbl = cap->maxstbl; 162 resgrp->version = cap->version; 163 } 164 } 165 166 static void s390_pci_read_util(S390PCIBusDevice *pbdev, 167 struct vfio_device_info *info) 168 { 169 struct vfio_info_cap_header *hdr; 170 struct vfio_device_info_cap_zpci_util *cap; 171 VFIOPCIDevice *vpci = container_of(pbdev->pdev, VFIOPCIDevice, pdev); 172 173 hdr = vfio_get_device_info_cap(info, VFIO_DEVICE_INFO_CAP_ZPCI_UTIL); 174 175 /* If capability not provided, just leave the defaults in place */ 176 if (hdr == NULL) { 177 trace_s390_pci_clp_cap(vpci->vbasedev.name, 178 VFIO_DEVICE_INFO_CAP_ZPCI_UTIL); 179 return; 180 } 181 cap = (void *) hdr; 182 183 if (cap->size > CLP_UTIL_STR_LEN) { 184 trace_s390_pci_clp_cap_size(vpci->vbasedev.name, cap->size, 185 VFIO_DEVICE_INFO_CAP_ZPCI_UTIL); 186 return; 187 } 188 189 pbdev->zpci_fn.flags |= CLP_RSP_QPCI_MASK_UTIL; 190 memcpy(pbdev->zpci_fn.util_str, cap->util_str, CLP_UTIL_STR_LEN); 191 } 192 193 static void s390_pci_read_pfip(S390PCIBusDevice *pbdev, 194 struct vfio_device_info *info) 195 { 196 struct vfio_info_cap_header *hdr; 197 struct vfio_device_info_cap_zpci_pfip *cap; 198 VFIOPCIDevice *vpci = container_of(pbdev->pdev, VFIOPCIDevice, pdev); 199 200 hdr = vfio_get_device_info_cap(info, VFIO_DEVICE_INFO_CAP_ZPCI_PFIP); 201 202 /* If capability not provided, just leave the defaults in place */ 203 if (hdr == NULL) { 204 trace_s390_pci_clp_cap(vpci->vbasedev.name, 205 VFIO_DEVICE_INFO_CAP_ZPCI_PFIP); 206 return; 207 } 208 cap = (void *) hdr; 209 210 if (cap->size > CLP_PFIP_NR_SEGMENTS) { 211 trace_s390_pci_clp_cap_size(vpci->vbasedev.name, cap->size, 212 VFIO_DEVICE_INFO_CAP_ZPCI_PFIP); 213 return; 214 } 215 216 memcpy(pbdev->zpci_fn.pfip, cap->pfip, CLP_PFIP_NR_SEGMENTS); 217 } 218 219 /* 220 * This function will issue the VFIO_DEVICE_GET_INFO ioctl and look for 221 * capabilities that contain information about CLP features provided by the 222 * underlying host. 223 * On entry, defaults have already been placed into the guest CLP response 224 * buffers. On exit, defaults will have been overwritten for any CLP features 225 * found in the capability chain; defaults will remain for any CLP features not 226 * found in the chain. 227 */ 228 void s390_pci_get_clp_info(S390PCIBusDevice *pbdev) 229 { 230 g_autofree struct vfio_device_info *info = NULL; 231 VFIOPCIDevice *vfio_pci; 232 uint32_t argsz; 233 int fd; 234 235 argsz = sizeof(*info); 236 info = g_malloc0(argsz); 237 238 vfio_pci = container_of(pbdev->pdev, VFIOPCIDevice, pdev); 239 fd = vfio_pci->vbasedev.fd; 240 241 /* 242 * If the specified argsz is not large enough to contain all capabilities 243 * it will be updated upon return from the ioctl. Retry until we have 244 * a big enough buffer to hold the entire capability chain. On error, 245 * just exit and rely on CLP defaults. 246 */ 247 retry: 248 info->argsz = argsz; 249 250 if (ioctl(fd, VFIO_DEVICE_GET_INFO, info)) { 251 trace_s390_pci_clp_dev_info(vfio_pci->vbasedev.name); 252 return; 253 } 254 255 if (info->argsz > argsz) { 256 argsz = info->argsz; 257 info = g_realloc(info, argsz); 258 goto retry; 259 } 260 261 /* 262 * Find the CLP features provided and fill in the guest CLP responses. 263 * Always call s390_pci_read_base first as information from this could 264 * determine which function group is used in s390_pci_read_group. 265 * For any feature not found, the default values will remain in the CLP 266 * response. 267 */ 268 s390_pci_read_base(pbdev, info); 269 s390_pci_read_group(pbdev, info); 270 s390_pci_read_util(pbdev, info); 271 s390_pci_read_pfip(pbdev, info); 272 273 return; 274 } 275