LXR qemu/fsdev/qemu-fsdev.c

   1/*
   2 * 9p
   3 *
   4 * Copyright IBM, Corp. 2010
   5 *
   6 * Authors:
   7 *  Gautham R Shenoy <ego@in.ibm.com>
   8 *
   9 * This work is licensed under the terms of the GNU GPL, version 2.  See
  10 * the COPYING file in the top-level directory.
  11 */
  12
  13#include "qemu/osdep.h"
  14#include "qapi/error.h"
  15#include "qemu-fsdev.h"
  16#include "qemu/queue.h"
  17#include "qemu/config-file.h"
  18#include "qemu/error-report.h"
  19#include "qemu/option.h"
  20
  21/*
  22 * A table to store the various file systems and their callback operations.
  23 * -----------------
  24 * fstype | ops
  25 * -----------------
  26 *  local | local_ops
  27 *  .     |
  28 *  .     |
  29 *  .     |
  30 *  .     |
  31 * -----------------
  32 *  etc
  33 */
  34typedef struct FsDriverTable {
  35    const char *name;
  36    FileOperations *ops;
  37    const char **opts;
  38} FsDriverTable;
  39
  40typedef struct FsDriverListEntry {
  41    FsDriverEntry fse;
  42    QTAILQ_ENTRY(FsDriverListEntry) next;
  43} FsDriverListEntry;
  44
  45static QTAILQ_HEAD(, FsDriverListEntry) fsdriver_entries =
  46    QTAILQ_HEAD_INITIALIZER(fsdriver_entries);
  47
  48#define COMMON_FS_DRIVER_OPTIONS "id", "fsdriver", "readonly"
  49
  50static FsDriverTable FsDrivers[] = {
  51    {
  52        .name = "local",
  53        .ops = &local_ops,
  54        .opts = (const char * []) {
  55            COMMON_FS_DRIVER_OPTIONS,
  56            "security_model",
  57            "path",
  58            "writeout",
  59            "fmode",
  60            "dmode",
  61            "multidevs",
  62            "throttling.bps-total",
  63            "throttling.bps-read",
  64            "throttling.bps-write",
  65            "throttling.iops-total",
  66            "throttling.iops-read",
  67            "throttling.iops-write",
  68            "throttling.bps-total-max",
  69            "throttling.bps-read-max",
  70            "throttling.bps-write-max",
  71            "throttling.iops-total-max",
  72            "throttling.iops-read-max",
  73            "throttling.iops-write-max",
  74            "throttling.bps-total-max-length",
  75            "throttling.bps-read-max-length",
  76            "throttling.bps-write-max-length",
  77            "throttling.iops-total-max-length",
  78            "throttling.iops-read-max-length",
  79            "throttling.iops-write-max-length",
  80            "throttling.iops-size",
  81        },
  82    },
  83    {
  84        .name = "synth",
  85        .ops = &synth_ops,
  86        .opts = (const char * []) {
  87            COMMON_FS_DRIVER_OPTIONS,
  88        },
  89    },
  90    {
  91        .name = "proxy",
  92        .ops = &proxy_ops,
  93        .opts = (const char * []) {
  94            COMMON_FS_DRIVER_OPTIONS,
  95            "socket",
  96            "sock_fd",
  97            "writeout",
  98        },
  99    },
 100};
 101
 102static int validate_opt(void *opaque, const char *name, const char *value,
 103                        Error **errp)
 104{
 105    FsDriverTable *drv = opaque;
 106    const char **opt;
 107
 108    for (opt = drv->opts; *opt; opt++) {
 109        if (!strcmp(*opt, name)) {
 110            return 0;
 111        }
 112    }
 113
 114    error_setg(errp, "'%s' is invalid for fsdriver '%s'", name, drv->name);
 115    return -1;
 116}
 117
 118int qemu_fsdev_add(QemuOpts *opts, Error **errp)
 119{
 120    int i;
 121    struct FsDriverListEntry *fsle;
 122    const char *fsdev_id = qemu_opts_id(opts);
 123    const char *fsdriver = qemu_opt_get(opts, "fsdriver");
 124    const char *writeout = qemu_opt_get(opts, "writeout");
 125    bool ro = qemu_opt_get_bool(opts, "readonly", 0);
 126
 127    if (!fsdev_id) {
 128        error_setg(errp, "fsdev: No id specified");
 129        return -1;
 130    }
 131
 132    if (fsdriver) {
 133        for (i = 0; i < ARRAY_SIZE(FsDrivers); i++) {
 134            if (strcmp(FsDrivers[i].name, fsdriver) == 0) {
 135                break;
 136            }
 137        }
 138
 139        if (i == ARRAY_SIZE(FsDrivers)) {
 140            error_setg(errp, "fsdev: fsdriver %s not found", fsdriver);
 141            return -1;
 142        }
 143    } else {
 144        error_setg(errp, "fsdev: No fsdriver specified");
 145        return -1;
 146    }
 147
 148    if (qemu_opt_foreach(opts, validate_opt, &FsDrivers[i], errp)) {
 149        return -1;
 150    }
 151
 152    fsle = g_malloc0(sizeof(*fsle));
 153    fsle->fse.fsdev_id = g_strdup(fsdev_id);
 154    fsle->fse.ops = FsDrivers[i].ops;
 155    if (writeout) {
 156        if (!strcmp(writeout, "immediate")) {
 157            fsle->fse.export_flags |= V9FS_IMMEDIATE_WRITEOUT;
 158        }
 159    }
 160    if (ro) {
 161        fsle->fse.export_flags |= V9FS_RDONLY;
 162    } else {
 163        fsle->fse.export_flags &= ~V9FS_RDONLY;
 164    }
 165
 166    if (fsle->fse.ops->parse_opts) {
 167        if (fsle->fse.ops->parse_opts(opts, &fsle->fse, errp)) {
 168            g_free(fsle->fse.fsdev_id);
 169            g_free(fsle);
 170            return -1;
 171        }
 172    }
 173
 174    QTAILQ_INSERT_TAIL(&fsdriver_entries, fsle, next);
 175    return 0;
 176}
 177
 178FsDriverEntry *get_fsdev_fsentry(char *id)
 179{
 180    if (id) {
 181        struct FsDriverListEntry *fsle;
 182
 183        QTAILQ_FOREACH(fsle, &fsdriver_entries, next) {
 184            if (strcmp(fsle->fse.fsdev_id, id) == 0) {
 185                return &fsle->fse;
 186            }
 187        }
 188    }
 189    return NULL;
 190}
 191