xref: /qemu/hw/9pfs/virtio-9p-device.c (revision e8111e50557761b0d86cd5c90fe7a272aeddd7a3)
1 /*
2  * Virtio 9p backend
3  *
4  * Copyright IBM, Corp. 2010
5  *
6  * Authors:
7  *  Anthony Liguori   <aliguori@us.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 
14 #include "hw/virtio/virtio.h"
15 #include "hw/virtio/virtio-9p.h"
16 #include "hw/i386/pc.h"
17 #include "qemu/sockets.h"
18 #include "virtio-9p.h"
19 #include "fsdev/qemu-fsdev.h"
20 #include "virtio-9p-xattr.h"
21 #include "virtio-9p-coth.h"
22 
23 static uint32_t virtio_9p_get_features(VirtIODevice *vdev, uint32_t features)
24 {
25     features |= 1 << VIRTIO_9P_MOUNT_TAG;
26     return features;
27 }
28 
29 static V9fsState *to_virtio_9p(VirtIODevice *vdev)
30 {
31     return (V9fsState *)vdev;
32 }
33 
34 static void virtio_9p_get_config(VirtIODevice *vdev, uint8_t *config)
35 {
36     int len;
37     struct virtio_9p_config *cfg;
38     V9fsState *s = to_virtio_9p(vdev);
39 
40     len = strlen(s->tag);
41     cfg = g_malloc0(sizeof(struct virtio_9p_config) + len);
42     stw_raw(&cfg->tag_len, len);
43     /* We don't copy the terminating null to config space */
44     memcpy(cfg->tag, s->tag, len);
45     memcpy(config, cfg, s->config_size);
46     g_free(cfg);
47 }
48 
49 static int virtio_9p_device_init(VirtIODevice *vdev)
50 {
51     V9fsState *s = VIRTIO_9P(vdev);
52     int i, len;
53     struct stat stat;
54     FsDriverEntry *fse;
55     V9fsPath path;
56 
57     virtio_init(VIRTIO_DEVICE(s), "virtio-9p", VIRTIO_ID_9P,
58                 sizeof(struct virtio_9p_config) + MAX_TAG_LEN);
59 
60     /* initialize pdu allocator */
61     QLIST_INIT(&s->free_list);
62     QLIST_INIT(&s->active_list);
63     for (i = 0; i < (MAX_REQ - 1); i++) {
64         QLIST_INSERT_HEAD(&s->free_list, &s->pdus[i], next);
65     }
66 
67     s->vq = virtio_add_queue(vdev, MAX_REQ, handle_9p_output);
68 
69     fse = get_fsdev_fsentry(s->fsconf.fsdev_id);
70 
71     if (!fse) {
72         /* We don't have a fsdev identified by fsdev_id */
73         fprintf(stderr, "Virtio-9p device couldn't find fsdev with the "
74                 "id = %s\n",
75                 s->fsconf.fsdev_id ? s->fsconf.fsdev_id : "NULL");
76         return -1;
77     }
78 
79     if (!s->fsconf.tag) {
80         /* we haven't specified a mount_tag */
81         fprintf(stderr, "fsdev with id %s needs mount_tag arguments\n",
82                 s->fsconf.fsdev_id);
83         return -1;
84     }
85 
86     s->ctx.export_flags = fse->export_flags;
87     s->ctx.fs_root = g_strdup(fse->path);
88     s->ctx.exops.get_st_gen = NULL;
89     len = strlen(s->fsconf.tag);
90     if (len > MAX_TAG_LEN - 1) {
91         fprintf(stderr, "mount tag '%s' (%d bytes) is longer than "
92                 "maximum (%d bytes)", s->fsconf.tag, len, MAX_TAG_LEN - 1);
93         return -1;
94     }
95 
96     s->tag = strdup(s->fsconf.tag);
97     s->ctx.uid = -1;
98 
99     s->ops = fse->ops;
100     s->vdev.get_features = virtio_9p_get_features;
101     s->config_size = sizeof(struct virtio_9p_config) + len;
102     s->vdev.get_config = virtio_9p_get_config;
103     s->fid_list = NULL;
104     qemu_co_rwlock_init(&s->rename_lock);
105 
106     if (s->ops->init(&s->ctx) < 0) {
107         fprintf(stderr, "Virtio-9p Failed to initialize fs-driver with id:%s"
108                 " and export path:%s\n", s->fsconf.fsdev_id, s->ctx.fs_root);
109         return -1;
110     }
111     if (v9fs_init_worker_threads() < 0) {
112         fprintf(stderr, "worker thread initialization failed\n");
113         return -1;
114     }
115 
116     /*
117      * Check details of export path, We need to use fs driver
118      * call back to do that. Since we are in the init path, we don't
119      * use co-routines here.
120      */
121     v9fs_path_init(&path);
122     if (s->ops->name_to_path(&s->ctx, NULL, "/", &path) < 0) {
123         fprintf(stderr,
124                 "error in converting name to path %s", strerror(errno));
125         return -1;
126     }
127     if (s->ops->lstat(&s->ctx, &path, &stat)) {
128         fprintf(stderr, "share path %s does not exist\n", fse->path);
129         return -1;
130     } else if (!S_ISDIR(stat.st_mode)) {
131         fprintf(stderr, "share path %s is not a directory\n", fse->path);
132         return -1;
133     }
134     v9fs_path_free(&path);
135 
136     return 0;
137 }
138 
139 /* virtio-9p device */
140 
141 static Property virtio_9p_properties[] = {
142     DEFINE_VIRTIO_9P_PROPERTIES(V9fsState, fsconf),
143     DEFINE_PROP_END_OF_LIST(),
144 };
145 
146 static void virtio_9p_class_init(ObjectClass *klass, void *data)
147 {
148     DeviceClass *dc = DEVICE_CLASS(klass);
149     VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass);
150     dc->props = virtio_9p_properties;
151     vdc->init = virtio_9p_device_init;
152     vdc->get_features = virtio_9p_get_features;
153     vdc->get_config = virtio_9p_get_config;
154 }
155 
156 static const TypeInfo virtio_device_info = {
157     .name = TYPE_VIRTIO_9P,
158     .parent = TYPE_VIRTIO_DEVICE,
159     .instance_size = sizeof(V9fsState),
160     .class_init = virtio_9p_class_init,
161 };
162 
163 static void virtio_9p_register_types(void)
164 {
165     type_register_static(&virtio_device_info);
166 }
167 
168 type_init(virtio_9p_register_types)
169