aboutsummaryrefslogtreecommitdiffstats
path: root/config/Config-kernel.in
Commit message (Expand)AuthorAgeFilesLines
* Kconfig: Various typo/grammar/line-length fixes in Config*.in filesHauke Mehrtens2014-09-131-15/+16
* config: enable cgroup freezerLuka Perkov2014-09-101-1/+1
* Disable crashlog for UMLSteven Barth2014-06-121-1/+1
* kernel: fix duplicate KERNEL_PERF_EVENTS with wrong dependencyFelix Fietkau2014-06-061-4/+1
* kernel: add a config option for enabling /proc/slabinfoFelix Fietkau2014-05-251-0/+11
* kernel: add a config option for /proc page monitoring (useful for detailed me...Felix Fietkau2014-05-251-0/+3
* sparse: add as a new package selectable from the configJohn Crispin2014-04-121-0/+4
* make printk, crashlog and swap support configurableImre Kaloz2014-04-021-1/+14
* config: lxc: enable KERNEL_POSIX_MQUEUELuka Perkov2014-01-241-1/+1
* config: add KERNEL_DYNAMIC_DEBUG optionLuka Perkov2013-12-091-0/+12
* move menuconfig options into separate filesImre Kaloz2013-11-221-0/+426
id='n157' href='#n157'>157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520
/*
 * Copyright (C) 2009      Citrix Ltd.
 * Author Vincent Hanquez <vincent.hanquez@eu.citrix.com>
 * Author Stefano Stabellini <stefano.stabellini@eu.citrix.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published
 * by the Free Software Foundation; version 2.1 only. with the special
 * exception on linking described in file LICENSE.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Lesser General Public License for more details.
 */

#include "libxl_osdeps.h"

#include <string.h>
#include <stdio.h>
#include <sys/time.h> /* for struct timeval */
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <fcntl.h>


#include "libxl.h"
#include "libxl_internal.h"

static const char *string_of_kinds[] = {
    [DEVICE_VIF] = "vif",
    [DEVICE_VIF2] = "vif2",
    [DEVICE_VBD] = "vbd",
    [DEVICE_TAP] = "tap",
    [DEVICE_QDISK] = "qdisk",
    [DEVICE_PCI] = "pci",
    [DEVICE_VFB] = "vfb",
    [DEVICE_VKBD] = "vkbd",
    [DEVICE_CONSOLE] = "console",
};

static char *libxl__device_frontend_path(libxl__gc *gc, libxl__device *device)
{
    char *dom_path = libxl__xs_get_dompath(gc, device->domid);

    /* Console 0 is a special case */
    if (device->kind == DEVICE_CONSOLE && device->devid == 0)
        return libxl__sprintf(gc, "%s/console", dom_path);

    return libxl__sprintf(gc, "%s/device/%s/%d", dom_path,
                          string_of_kinds[device->kind], device->devid);
}

static char *libxl__device_backend_path(libxl__gc *gc, libxl__device *device)
{
    char *dom_path = libxl__xs_get_dompath(gc, device->backend_domid);

    return libxl__sprintf(gc, "%s/backend/%s/%u/%d", dom_path,
                          string_of_kinds[device->backend_kind],
                          device->domid, device->devid);
}

int libxl__device_generic_add(libxl_ctx *ctx, libxl__device *device,
                             char **bents, char **fents)
{
    libxl__gc gc = LIBXL_INIT_GC(ctx);
    char *frontend_path, *backend_path;
    xs_transaction_t t;
    struct xs_permissions frontend_perms[2];
    struct xs_permissions backend_perms[2];
    int rc;

    if (!is_valid_device_kind(device->backend_kind) || !is_valid_device_kind(device->kind)) {
        rc = ERROR_INVAL;
        goto out;
    }

    frontend_path = libxl__device_frontend_path(&gc, device);
    backend_path = libxl__device_backend_path(&gc, device);

    frontend_perms[0].id = device->domid;
    frontend_perms[0].perms = XS_PERM_NONE;
    frontend_perms[1].id = device->backend_domid;
    frontend_perms[1].perms = XS_PERM_READ;

    backend_perms[0].id = device->backend_domid;
    backend_perms[0].perms = XS_PERM_NONE;
    backend_perms[1].id = device->domid;
    backend_perms[1].perms = XS_PERM_READ;

retry_transaction:
    t = xs_transaction_start(ctx->xsh);
    /* FIXME: read frontend_path and check state before removing stuff */

    if (fents) {
        xs_rm(ctx->xsh, t, frontend_path);
        xs_mkdir(ctx->xsh, t, frontend_path);
        xs_set_permissions(ctx->xsh, t, frontend_path, frontend_perms, ARRAY_SIZE(frontend_perms));
        xs_write(ctx->xsh, t, libxl__sprintf(&gc, "%s/backend", frontend_path), backend_path, strlen(backend_path));
        libxl__xs_writev(&gc, t, frontend_path, fents);
    }

    if (bents) {
        xs_rm(ctx->xsh, t, backend_path);
        xs_mkdir(ctx->xsh, t, backend_path);
        xs_set_permissions(ctx->xsh, t, backend_path, backend_perms, ARRAY_SIZE(backend_perms));
        xs_write(ctx->xsh, t, libxl__sprintf(&gc, "%s/frontend", backend_path), frontend_path, strlen(frontend_path));
        libxl__xs_writev(&gc, t, backend_path, bents);
    }

    if (!xs_transaction_end(ctx->xsh, t, 0)) {
        if (errno == EAGAIN)
            goto retry_transaction;
        else
            LIBXL__LOG_ERRNO(ctx, LIBXL__LOG_ERROR, "xs transaction failed");
    }
    rc = 0;
out:
    libxl__free_all(&gc);
    return rc;
}

char *libxl__device_disk_string_of_phystype(libxl_disk_phystype phystype)
{
    switch (phystype) {
        case PHYSTYPE_QCOW: return "qcow";
        case PHYSTYPE_QCOW2: return "qcow2";
        case PHYSTYPE_VHD: return "vhd";
        case PHYSTYPE_AIO: return "aio";
        case PHYSTYPE_FILE: return "file";
        case PHYSTYPE_PHY: return "phy";
        case PHYSTYPE_EMPTY: return "file";
        default: return NULL;
    }
}

char *libxl__device_disk_backend_type_of_phystype(libxl_disk_phystype phystype)
{
    switch (phystype) {
        case PHYSTYPE_QCOW: return "tap";
        case PHYSTYPE_QCOW2: return "tap";
        case PHYSTYPE_VHD: return "tap";
        case PHYSTYPE_AIO: return "tap";
        /* let's pretend file is tap:aio */
        case PHYSTYPE_FILE: return "tap";
        case PHYSTYPE_EMPTY: return "tap";
        case PHYSTYPE_PHY: return "phy";
        default: return NULL;
    }
}

int libxl__device_physdisk_major_minor(const char *physpath, int *major, int *minor)
{
    struct stat buf;
    if (stat(physpath, &buf) < 0)
        return -1;
    *major = major(buf.st_rdev);
    *minor = minor(buf.st_rdev);
    return 0;
}

static int device_virtdisk_matches(const char *virtpath, const char *devtype,
                                   int *index_r, int max_index,
                                   int *partition_r, int max_partition) {
    const char *p;
    char *ep;
    int tl, c;
    long pl;

    tl = strlen(devtype);
    if (memcmp(virtpath, devtype, tl))
        return 0;

    /* We decode the drive letter as if it were in base 52
     * with digits a-zA-Z, more or less */
    *index_r = -1;
    p = virtpath + tl;
    for (;;) {
        c = *p++;
        if (c >= 'a' && c <= 'z') {
            c -= 'a';
        } else {
            --p;
            break;
        }
        (*index_r)++;
        (*index_r) *= 26;
        (*index_r) += c;

        if (*index_r > max_index)
            return 0;
    }

    if (!*p) {
        *partition_r = 0;
        return 1;
    }

    if (*p=='0')
        return 0; /* leading zeroes not permitted in partition number */

    pl = strtoul(p, &ep, 10);
    if (pl > max_partition || *ep)
        return 0;

    *partition_r = pl;
    return 1;
}

int libxl__device_disk_dev_number(char *virtpath)
{
    int disk, partition;
    char *ep;
    unsigned long ul;
    int chrused;

    chrused = -1;
    if ((sscanf(virtpath, "d%ip%i%n", &disk, &partition, &chrused)  >= 2
         && chrused == strlen(virtpath) && disk < (1<<20) && partition < 256)
        ||
        device_virtdisk_matches(virtpath, "xvd",
                                &disk, (1<<20)-1,
                                &partition, 255)) {
        if (disk <= 15 && partition <= 15)
            return (202 << 8) | (disk << 4) | partition;
        else
            return (1 << 28) | (disk << 8) | partition;
    }

    errno = 0;
    ul = strtoul(virtpath, &ep, 0);
    if (!errno && !*ep && ul <= INT_MAX)
        return ul;

    if (device_virtdisk_matches(virtpath, "hd",
                                &disk, 3,
                                &partition, 63)) {
        return ((disk<2 ? 3 : 22) << 8) | ((disk & 1) << 6) | partition;
    }
    if (device_virtdisk_matches(virtpath, "sd",
                                &disk, 15,
                                &partition, 15)) {
        return (8 << 8) | (disk << 4) | partition;
    }
    return -1;
}

int libxl__device_destroy(libxl_ctx *ctx, char *be_path, int force)
{
    libxl__gc gc = LIBXL_INIT_GC(ctx);
    xs_transaction_t t;
    char *state_path = libxl__sprintf(&gc, "%s/state", be_path);
    char *state = libxl__xs_read(&gc, XBT_NULL, state_path);
    int rc = 0;

    if (!state)
        goto out;
    if (atoi(state) != 4) {
        xs_rm(ctx->xsh, XBT_NULL, be_path);
        goto out;
    }

retry_transaction:
    t = xs_transaction_start(ctx->xsh);
    xs_write(ctx->xsh, t, libxl__sprintf(&gc, "%s/online", be_path), "0", strlen("0"));
    xs_write(ctx->xsh, t, state_path, "5", strlen("5"));
    if (!xs_transaction_end(ctx->xsh, t, 0)) {
        if (errno == EAGAIN)
            goto retry_transaction;
        else {
            rc = -1;
            goto out;
        }
    }
    if (!force) {
        xs_watch(ctx->xsh, state_path, be_path);
        rc = 1;
    }
out:
    libxl__free_all(&gc);
    return rc;
}

static int wait_for_dev_destroy(libxl_ctx *ctx, struct timeval *tv)
{
    libxl__gc gc = LIBXL_INIT_GC(ctx);
    int nfds, rc;
    unsigned int n;
    fd_set rfds;
    char **l1 = NULL;

    rc = 1;
    nfds = xs_fileno(ctx->xsh) + 1;
    FD_ZERO(&rfds);
    FD_SET(xs_fileno(ctx->xsh), &rfds);
    if (select(nfds, &rfds, NULL, NULL, tv) > 0) {
        l1 = xs_read_watch(ctx->xsh, &n);
        if (l1 != NULL) {
            char *state = libxl__xs_read(&gc, XBT_NULL, l1[XS_WATCH_PATH]);
            if (!state || atoi(state) == 6) {
                xs_unwatch(ctx->xsh, l1[0], l1[1]);
                xs_rm(ctx->xsh, XBT_NULL, l1[XS_WATCH_TOKEN]);
                LIBXL__LOG(ctx, LIBXL__LOG_DEBUG, "Destroyed device backend at %s", l1[XS_WATCH_TOKEN]);
                rc = 0;
            }
            free(l1);
        }
    }
    libxl__free_all(&gc);
    return rc;
}

int libxl__devices_destroy(libxl_ctx *ctx, uint32_t domid, int force)
{
    libxl__gc gc = LIBXL_INIT_GC(ctx);
    char *path, *be_path, *fe_path;
    unsigned int num1, num2;
    char **l1 = NULL, **l2 = NULL;
    int i, j, n = 0, n_watches = 0;
    flexarray_t *toremove;

    toremove = flexarray_make(16, 1);
    path = libxl__sprintf(&gc, "/local/domain/%d/device", domid);
    l1 = libxl__xs_directory(&gc, XBT_NULL, path, &num1);
    if (!l1) {
        LIBXL__LOG(ctx, LIBXL__LOG_ERROR, "%s is empty", path);
        goto out;
    }
    for (i = 0; i < num1; i++) {
        if (!strcmp("vfs", l1[i]))
            continue;
        path = libxl__sprintf(&gc, "/local/domain/%d/device/%s", domid, l1[i]);
        l2 = libxl__xs_directory(&gc, XBT_NULL, path, &num2);
        if (!l2)
            continue;
        for (j = 0; j < num2; j++) {
            fe_path = libxl__sprintf(&gc, "/local/domain/%d/device/%s/%s", domid, l1[i], l2[j]);
            be_path = libxl__xs_read(&gc, XBT_NULL, libxl__sprintf(&gc, "%s/backend", fe_path));
            if (be_path != NULL) {
                if (libxl__device_destroy(ctx, be_path, force) > 0)
                    n_watches++;
                flexarray_set(toremove, n++, libxl__dirname(&gc, be_path));
            } else {
                xs_rm(ctx->xsh, XBT_NULL, path);
            }
        }
    }

    /* console 0 frontend directory is not under /local/domain/<domid>/device */
    fe_path = libxl__sprintf(&gc, "/local/domain/%d/console", domid);
    be_path = libxl__xs_read(&gc, XBT_NULL, libxl__sprintf(&gc, "%s/backend", fe_path));
    if (be_path && strcmp(be_path, "")) {
        if (libxl__device_destroy(ctx, be_path, force) > 0)
            n_watches++;
        flexarray_set(toremove, n++, libxl__dirname(&gc, be_path));
    }

    if (!force) {
        /* Linux-ism. Most implementations leave the timeout
         * untouched after select. Linux, however, will chip
         * away the elapsed time from it, which is what we 
         * need to enforce a single time span waiting for
         * device destruction. */
        struct timeval tv;
        tv.tv_sec = LIBXL_DESTROY_TIMEOUT;
        tv.tv_usec = 0;
        while (n_watches > 0) {
            if (wait_for_dev_destroy(ctx, &tv)) {
                break;
            } else {
                n_watches--;
            }
        }
    }
    for (i = 0; i < n; i++) {
        flexarray_get(toremove, i, (void**) &path);
        xs_rm(ctx->xsh, XBT_NULL, path);
    }
out:
    flexarray_free(toremove);
    libxl__free_all(&gc);
    return 0;
}

int libxl__device_del(libxl_ctx *ctx, libxl__device *dev, int wait)
{
    libxl__gc gc = LIBXL_INIT_GC(ctx);
    char *backend_path;
    int rc;

    backend_path = libxl__device_backend_path(&gc, dev);

    rc = libxl__device_destroy(ctx, backend_path, !wait);
    if (rc == -1) {
        rc = ERROR_FAIL;
        goto out;
    }

    if (wait) {
        struct timeval tv;
        tv.tv_sec = LIBXL_DESTROY_TIMEOUT;
        tv.tv_usec = 0;
        (void)wait_for_dev_destroy(ctx, &tv);
    }

    rc = 0;

out:
    libxl__free_all(&gc);
    return rc;
}

int libxl__wait_for_device_model(libxl_ctx *ctx,
                                uint32_t domid, char *state,
                                int (*check_callback)(libxl_ctx *ctx,
                                                      uint32_t domid,
                                                      const char *state,
                                                      void *userdata),
                                void *check_callback_userdata)
{
    libxl__gc gc = LIBXL_INIT_GC(ctx);
    char *path;
    char *p;
    unsigned int len;
    int rc = 0;
    struct xs_handle *xsh;
    int nfds;
    fd_set rfds;
    struct timeval tv;
    unsigned int num;
    char **l = NULL;

    xsh = xs_daemon_open();
    if (xsh == NULL) {
        LIBXL__LOG(ctx, LIBXL__LOG_ERROR, "Unable to open xenstore connection");
        goto err;
    }

    path = libxl__sprintf(&gc, "/local/domain/0/device-model/%d/state", domid);
    xs_watch(xsh, path, path);
    tv.tv_sec = LIBXL_DEVICE_MODEL_START_TIMEOUT;
    tv.tv_usec = 0;
    nfds = xs_fileno(xsh) + 1;
    while (rc > 0 || (!rc && tv.tv_sec > 0)) {
        p = xs_read(xsh, XBT_NULL, path, &len);
        if ( NULL == p )
            goto again;

        if ( NULL != state && strcmp(p, state) )
            goto again;

        if ( NULL != check_callback ) {
            rc = (*check_callback)(ctx, domid, p, check_callback_userdata);
            if ( rc > 0 )
                goto again;
        }

        free(p);
        xs_unwatch(xsh, path, path);
        xs_daemon_close(xsh);
        libxl__free_all(&gc);
        return rc;
again:
        free(p);
        FD_ZERO(&rfds);
        FD_SET(xs_fileno(xsh), &rfds);
        rc = select(nfds, &rfds, NULL, NULL, &tv);
        if (rc > 0) {
            l = xs_read_watch(xsh, &num);
            if (l != NULL)
                free(l);
            else
                goto again;
        }
    }
    xs_unwatch(xsh, path, path);
    xs_daemon_close(xsh);
    LIBXL__LOG(ctx, LIBXL__LOG_ERROR, "Device Model not ready");
err:
    libxl__free_all(&gc);
    return -1;
}

int libxl__wait_for_backend(libxl_ctx *ctx, char *be_path, char *state)
{
    libxl__gc gc = LIBXL_INIT_GC(ctx);
    int watchdog = 100;
    unsigned int len;
    char *p;
    char *path = libxl__sprintf(&gc, "%s/state", be_path);
    int rc = -1;

    while (watchdog > 0) {
        p = xs_read(ctx->xsh, XBT_NULL, path, &len);
        if (p == NULL) {
            if (errno == ENOENT) {
                LIBXL__LOG(ctx, LIBXL__LOG_ERROR, "Backend %s does not exist",
                       be_path);
            } else {
                LIBXL__LOG_ERRNO(ctx, LIBXL__LOG_ERROR, "Failed to access backend %s",
                       be_path);
            }
            goto out;
        } else {
            if (!strcmp(p, state)) {
                rc = 0;
                goto out;
            } else {
                usleep(100000);
                watchdog--;
            }
        }
    }
    LIBXL__LOG(ctx, LIBXL__LOG_ERROR, "Backend %s not ready", be_path);
out:
    libxl__free_all(&gc);
    return rc;
}