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  */
  34 typedef struct FsDriverTable {
  35     const char *name;
  36     FileOperations *ops;
  37 } FsDriverTable;
  38
  39 typedef struct FsDriverListEntry {
  40     FsDriverEntry fse;
  41     QTAILQ_ENTRY(FsDriverListEntry) next;
  42 } FsDriverListEntry;
  43
  44 static QTAILQ_HEAD(, FsDriverListEntry) fsdriver_entries =
  45     QTAILQ_HEAD_INITIALIZER(fsdriver_entries);
  46
  47 static FsDriverTable FsDrivers[] = {
  48     { .name = "local", .ops = &local_ops},
  49     { .name = "synth", .ops = &synth_ops},
  50     { .name = "proxy", .ops = &proxy_ops},
  51 };
  52
  53 int qemu_fsdev_add(QemuOpts *opts, Error **errp)
  54 {
  55     int i;
  56     struct FsDriverListEntry *fsle;
  57     const char *fsdev_id = qemu_opts_id(opts);
  58     const char *fsdriver = qemu_opt_get(opts, "fsdriver");
  59     const char *writeout = qemu_opt_get(opts, "writeout");
  60     bool ro = qemu_opt_get_bool(opts, "readonly", 0);
  61
  62     if (!fsdev_id) {
  63         error_setg(errp, "fsdev: No id specified");
  64         return -1;
  65     }
  66
  67     if (fsdriver) {
  68         for (i = 0; i < ARRAY_SIZE(FsDrivers); i++) {
  69             if (strcmp(FsDrivers[i].name, fsdriver) == 0) {
  70                 break;
  71             }
  72         }
  73
  74         if (i == ARRAY_SIZE(FsDrivers)) {
  75             error_setg(errp, "fsdev: fsdriver %s not found", fsdriver);
  76             return -1;
  77         }
  78     } else {
  79         error_setg(errp, "fsdev: No fsdriver specified");
  80         return -1;
  81     }
  82
  83     fsle = g_malloc0(sizeof(*fsle));
  84     fsle->fse.fsdev_id = g_strdup(fsdev_id);
  85     fsle->fse.ops = FsDrivers[i].ops;
  86     if (writeout) {
  87         if (!strcmp(writeout, "immediate")) {
  88             fsle->fse.export_flags |= V9FS_IMMEDIATE_WRITEOUT;
  89         }
  90     }
  91     if (ro) {
  92         fsle->fse.export_flags |= V9FS_RDONLY;
  93     } else {
  94         fsle->fse.export_flags &= ~V9FS_RDONLY;
  95     }
  96
  97     if (fsle->fse.ops->parse_opts) {
  98         if (fsle->fse.ops->parse_opts(opts, &fsle->fse, errp)) {
  99             g_free(fsle->fse.fsdev_id);
 100             g_free(fsle);
 101             return -1;
 102         }
 103     }
 104
 105     QTAILQ_INSERT_TAIL(&fsdriver_entries, fsle, next);
 106     return 0;
 107 }
 108
 109 FsDriverEntry *get_fsdev_fsentry(char *id)
 110 {
 111     if (id) {
 112         struct FsDriverListEntry *fsle;
 113
 114         QTAILQ_FOREACH(fsle, &fsdriver_entries, next) {
 115             if (strcmp(fsle->fse.fsdev_id, id) == 0) {
 116                 return &fsle->fse;
 117             }
 118         }
 119     }
 120     return NULL;
 121 }