hw/xen/xen-host-pci-device.c

   1 /*
   2  * Copyright (C) 2011       Citrix Ltd.
   3  *
   4  * This work is licensed under the terms of the GNU GPL, version 2.  See
   5  * the COPYING file in the top-level directory.
   6  *
   7  */
   8
   9 #include "qemu/osdep.h"
  10 #include "qapi/error.h"
  11 #include "qemu-common.h"
  12 #include "qemu/cutils.h"
  13 #include "xen-host-pci-device.h"
  14
  15 #define XEN_HOST_PCI_MAX_EXT_CAP \
  16     ((PCIE_CONFIG_SPACE_SIZE - PCI_CONFIG_SPACE_SIZE) / (PCI_CAP_SIZEOF + 4))
  17
  18 #ifdef XEN_HOST_PCI_DEVICE_DEBUG
  19 #  define XEN_HOST_PCI_LOG(f, a...) fprintf(stderr, "%s: " f, __func__, ##a)
  20 #else
  21 #  define XEN_HOST_PCI_LOG(f, a...) (void)0
  22 #endif
  23
  24 /*
  25  * from linux/ioport.h
  26  * IO resources have these defined flags.
  27  */
  28 #define IORESOURCE_BITS         0x000000ff      /* Bus-specific bits */
  29
  30 #define IORESOURCE_TYPE_BITS    0x00000f00      /* Resource type */
  31 #define IORESOURCE_IO           0x00000100
  32 #define IORESOURCE_MEM          0x00000200
  33
  34 #define IORESOURCE_PREFETCH     0x00001000      /* No side effects */
  35 #define IORESOURCE_MEM_64       0x00100000
  36
  37 static void xen_host_pci_sysfs_path(const XenHostPCIDevice *d,
  38                                     const char *name, char *buf, ssize_t size)
  39 {
  40     int rc;
  41
  42     rc = snprintf(buf, size, "/sys/bus/pci/devices/%04x:%02x:%02x.%d/%s",
  43                   d->domain, d->bus, d->dev, d->func, name);
  44     assert(rc >= 0 && rc < size);
  45 }
  46
  47
  48 /* This size should be enough to read the first 7 lines of a resource file */
  49 #define XEN_HOST_PCI_RESOURCE_BUFFER_SIZE 400
  50 static void xen_host_pci_get_resource(XenHostPCIDevice *d, Error **errp)
  51 {
  52     int i, rc, fd;
  53     char path[PATH_MAX];
  54     char buf[XEN_HOST_PCI_RESOURCE_BUFFER_SIZE];
  55     unsigned long long start, end, flags, size;
  56     char *endptr, *s;
  57     uint8_t type;
  58
  59     xen_host_pci_sysfs_path(d, "resource", path, sizeof(path));
  60
  61     fd = open(path, O_RDONLY);
  62     if (fd == -1) {
  63         error_setg_file_open(errp, errno, path);
  64         return;
  65     }
  66
  67     do {
  68         rc = read(fd, &buf, sizeof(buf) - 1);
  69         if (rc < 0 && errno != EINTR) {
  70             error_setg_errno(errp, errno, "read err");
  71             goto out;
  72         }
  73     } while (rc < 0);
  74     buf[rc] = 0;
  75
  76     s = buf;
  77     for (i = 0; i < PCI_NUM_REGIONS; i++) {
  78         type = 0;
  79
  80         start = strtoll(s, &endptr, 16);
  81         if (*endptr != ' ' || s == endptr) {
  82             break;
  83         }
  84         s = endptr + 1;
  85         end = strtoll(s, &endptr, 16);
  86         if (*endptr != ' ' || s == endptr) {
  87             break;
  88         }
  89         s = endptr + 1;
  90         flags = strtoll(s, &endptr, 16);
  91         if (*endptr != '\n' || s == endptr) {
  92             break;
  93         }
  94         s = endptr + 1;
  95
  96         if (start) {
  97             size = end - start + 1;
  98         } else {
  99             size = 0;
 100         }
 101
 102         if (flags & IORESOURCE_IO) {
 103             type |= XEN_HOST_PCI_REGION_TYPE_IO;
 104         }
 105         if (flags & IORESOURCE_MEM) {
 106             type |= XEN_HOST_PCI_REGION_TYPE_MEM;
 107         }
 108         if (flags & IORESOURCE_PREFETCH) {
 109             type |= XEN_HOST_PCI_REGION_TYPE_PREFETCH;
 110         }
 111         if (flags & IORESOURCE_MEM_64) {
 112             type |= XEN_HOST_PCI_REGION_TYPE_MEM_64;
 113         }
 114
 115         if (i < PCI_ROM_SLOT) {
 116             d->io_regions[i].base_addr = start;
 117             d->io_regions[i].size = size;
 118             d->io_regions[i].type = type;
 119             d->io_regions[i].bus_flags = flags & IORESOURCE_BITS;
 120         } else {
 121             d->rom.base_addr = start;
 122             d->rom.size = size;
 123             d->rom.type = type;
 124             d->rom.bus_flags = flags & IORESOURCE_BITS;
 125         }
 126     }
 127
 128     if (i != PCI_NUM_REGIONS) {
 129         error_setg(errp, "Invalid format or input too short: %s", buf);
 130     }
 131
 132 out:
 133     close(fd);
 134 }
 135
 136 /* This size should be enough to read a long from a file */
 137 #define XEN_HOST_PCI_GET_VALUE_BUFFER_SIZE 22
 138 static void xen_host_pci_get_value(XenHostPCIDevice *d, const char *name,
 139                                    unsigned int *pvalue, int base, Error **errp)
 140 {
 141     char path[PATH_MAX];
 142     char buf[XEN_HOST_PCI_GET_VALUE_BUFFER_SIZE];
 143     int fd, rc;
 144     unsigned long value;
 145     const char *endptr;
 146
 147     xen_host_pci_sysfs_path(d, name, path, sizeof(path));
 148
 149     fd = open(path, O_RDONLY);
 150     if (fd == -1) {
 151         error_setg_file_open(errp, errno, path);
 152         return;
 153     }
 154
 155     do {
 156         rc = read(fd, &buf, sizeof(buf) - 1);
 157         if (rc < 0 && errno != EINTR) {
 158             error_setg_errno(errp, errno, "read err");
 159             goto out;
 160         }
 161     } while (rc < 0);
 162
 163     buf[rc] = 0;
 164     rc = qemu_strtoul(buf, &endptr, base, &value);
 165     if (!rc) {
 166         assert(value <= UINT_MAX);
 167         *pvalue = value;
 168     } else {
 169         error_setg_errno(errp, -rc, "failed to parse value '%s'", buf);
 170     }
 171
 172 out:
 173     close(fd);
 174 }
 175
 176 static inline void xen_host_pci_get_hex_value(XenHostPCIDevice *d,
 177                                               const char *name,
 178                                               unsigned int *pvalue,
 179                                               Error **errp)
 180 {
 181     xen_host_pci_get_value(d, name, pvalue, 16, errp);
 182 }
 183
 184 static inline void xen_host_pci_get_dec_value(XenHostPCIDevice *d,
 185                                               const char *name,
 186                                               unsigned int *pvalue,
 187                                               Error **errp)
 188 {
 189     xen_host_pci_get_value(d, name, pvalue, 10, errp);
 190 }
 191
 192 static bool xen_host_pci_dev_is_virtfn(XenHostPCIDevice *d)
 193 {
 194     char path[PATH_MAX];
 195     struct stat buf;
 196
 197     xen_host_pci_sysfs_path(d, "physfn", path, sizeof(path));
 198
 199     return !stat(path, &buf);
 200 }
 201
 202 static void xen_host_pci_config_open(XenHostPCIDevice *d, Error **errp)
 203 {
 204     char path[PATH_MAX];
 205
 206     xen_host_pci_sysfs_path(d, "config", path, sizeof(path));
 207
 208     d->config_fd = open(path, O_RDWR);
 209     if (d->config_fd == -1) {
 210         error_setg_file_open(errp, errno, path);
 211     }
 212 }
 213
 214 static int xen_host_pci_config_read(XenHostPCIDevice *d,
 215                                     int pos, void *buf, int len)
 216 {
 217     int rc;
 218
 219     do {
 220         rc = pread(d->config_fd, buf, len, pos);
 221     } while (rc < 0 && (errno == EINTR || errno == EAGAIN));
 222     if (rc != len) {
 223         return -errno;
 224     }
 225     return 0;
 226 }
 227
 228 static int xen_host_pci_config_write(XenHostPCIDevice *d,
 229                                      int pos, const void *buf, int len)
 230 {
 231     int rc;
 232
 233     do {
 234         rc = pwrite(d->config_fd, buf, len, pos);
 235     } while (rc < 0 && (errno == EINTR || errno == EAGAIN));
 236     if (rc != len) {
 237         return -errno;
 238     }
 239     return 0;
 240 }
 241
 242
 243 int xen_host_pci_get_byte(XenHostPCIDevice *d, int pos, uint8_t *p)
 244 {
 245     uint8_t buf;
 246     int rc = xen_host_pci_config_read(d, pos, &buf, 1);
 247     if (!rc) {
 248         *p = buf;
 249     }
 250     return rc;
 251 }
 252
 253 int xen_host_pci_get_word(XenHostPCIDevice *d, int pos, uint16_t *p)
 254 {
 255     uint16_t buf;
 256     int rc = xen_host_pci_config_read(d, pos, &buf, 2);
 257     if (!rc) {
 258         *p = le16_to_cpu(buf);
 259     }
 260     return rc;
 261 }
 262
 263 int xen_host_pci_get_long(XenHostPCIDevice *d, int pos, uint32_t *p)
 264 {
 265     uint32_t buf;
 266     int rc = xen_host_pci_config_read(d, pos, &buf, 4);
 267     if (!rc) {
 268         *p = le32_to_cpu(buf);
 269     }
 270     return rc;
 271 }
 272
 273 int xen_host_pci_get_block(XenHostPCIDevice *d, int pos, uint8_t *buf, int len)
 274 {
 275     return xen_host_pci_config_read(d, pos, buf, len);
 276 }
 277
 278 int xen_host_pci_set_byte(XenHostPCIDevice *d, int pos, uint8_t data)
 279 {
 280     return xen_host_pci_config_write(d, pos, &data, 1);
 281 }
 282
 283 int xen_host_pci_set_word(XenHostPCIDevice *d, int pos, uint16_t data)
 284 {
 285     data = cpu_to_le16(data);
 286     return xen_host_pci_config_write(d, pos, &data, 2);
 287 }
 288
 289 int xen_host_pci_set_long(XenHostPCIDevice *d, int pos, uint32_t data)
 290 {
 291     data = cpu_to_le32(data);
 292     return xen_host_pci_config_write(d, pos, &data, 4);
 293 }
 294
 295 int xen_host_pci_set_block(XenHostPCIDevice *d, int pos, uint8_t *buf, int len)
 296 {
 297     return xen_host_pci_config_write(d, pos, buf, len);
 298 }
 299
 300 int xen_host_pci_find_ext_cap_offset(XenHostPCIDevice *d, uint32_t cap)
 301 {
 302     uint32_t header = 0;
 303     int max_cap = XEN_HOST_PCI_MAX_EXT_CAP;
 304     int pos = PCI_CONFIG_SPACE_SIZE;
 305
 306     do {
 307         if (xen_host_pci_get_long(d, pos, &header)) {
 308             break;
 309         }
 310         /*
 311          * If we have no capabilities, this is indicated by cap ID,
 312          * cap version and next pointer all being 0.
 313          */
 314         if (header == 0) {
 315             break;
 316         }
 317
 318         if (PCI_EXT_CAP_ID(header) == cap) {
 319             return pos;
 320         }
 321
 322         pos = PCI_EXT_CAP_NEXT(header);
 323         if (pos < PCI_CONFIG_SPACE_SIZE) {
 324             break;
 325         }
 326
 327         max_cap--;
 328     } while (max_cap > 0);
 329
 330     return -1;
 331 }
 332
 333 void xen_host_pci_device_get(XenHostPCIDevice *d, uint16_t domain,
 334                              uint8_t bus, uint8_t dev, uint8_t func,
 335                              Error **errp)
 336 {
 337     unsigned int v;
 338     Error *err = NULL;
 339
 340     d->config_fd = -1;
 341     d->domain = domain;
 342     d->bus = bus;
 343     d->dev = dev;
 344     d->func = func;
 345
 346     xen_host_pci_config_open(d, &err);
 347     if (err) {
 348         goto error;
 349     }
 350
 351     xen_host_pci_get_resource(d, &err);
 352     if (err) {
 353         goto error;
 354     }
 355
 356     xen_host_pci_get_hex_value(d, "vendor", &v, &err);
 357     if (err) {
 358         goto error;
 359     }
 360     d->vendor_id = v;
 361
 362     xen_host_pci_get_hex_value(d, "device", &v, &err);
 363     if (err) {
 364         goto error;
 365     }
 366     d->device_id = v;
 367
 368     xen_host_pci_get_dec_value(d, "irq", &v, &err);
 369     if (err) {
 370         goto error;
 371     }
 372     d->irq = v;
 373
 374     xen_host_pci_get_hex_value(d, "class", &v, &err);
 375     if (err) {
 376         goto error;
 377     }
 378     d->class_code = v;
 379
 380     d->is_virtfn = xen_host_pci_dev_is_virtfn(d);
 381
 382     return;
 383
 384 error:
 385     error_propagate(errp, err);
 386
 387     if (d->config_fd >= 0) {
 388         close(d->config_fd);
 389         d->config_fd = -1;
 390     }
 391 }
 392
 393 bool xen_host_pci_device_closed(XenHostPCIDevice *d)
 394 {
 395     return d->config_fd == -1;
 396 }
 397
 398 void xen_host_pci_device_put(XenHostPCIDevice *d)
 399 {
 400     if (d->config_fd >= 0) {
 401         close(d->config_fd);
 402         d->config_fd = -1;
 403     }
 404 }