xref: /openbmc/qemu/hw/9pfs/virtio-9p-device.c (revision 203439ce)
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 void virtio_9p_get_config(VirtIODevice *vdev, uint8_t *config)
30 {
31     int len;
32     struct virtio_9p_config *cfg;
33     V9fsState *s = VIRTIO_9P(vdev);
34 
35     len = strlen(s->tag);
36     cfg = g_malloc0(sizeof(struct virtio_9p_config) + len);
37     stw_raw(&cfg->tag_len, len);
38     /* We don't copy the terminating null to config space */
39     memcpy(cfg->tag, s->tag, len);
40     memcpy(config, cfg, s->config_size);
41     g_free(cfg);
42 }
43 
44 static int virtio_9p_device_init(VirtIODevice *vdev)
45 {
46     V9fsState *s = VIRTIO_9P(vdev);
47     int i, len;
48     struct stat stat;
49     FsDriverEntry *fse;
50     V9fsPath path;
51 
52     virtio_init(VIRTIO_DEVICE(s), "virtio-9p", VIRTIO_ID_9P,
53                 sizeof(struct virtio_9p_config) + MAX_TAG_LEN);
54 
55     /* initialize pdu allocator */
56     QLIST_INIT(&s->free_list);
57     QLIST_INIT(&s->active_list);
58     for (i = 0; i < (MAX_REQ - 1); i++) {
59         QLIST_INSERT_HEAD(&s->free_list, &s->pdus[i], next);
60     }
61 
62     s->vq = virtio_add_queue(vdev, MAX_REQ, handle_9p_output);
63 
64     v9fs_path_init(&path);
65 
66     fse = get_fsdev_fsentry(s->fsconf.fsdev_id);
67 
68     if (!fse) {
69         /* We don't have a fsdev identified by fsdev_id */
70         fprintf(stderr, "Virtio-9p device couldn't find fsdev with the "
71                 "id = %s\n",
72                 s->fsconf.fsdev_id ? s->fsconf.fsdev_id : "NULL");
73         goto out;
74     }
75 
76     if (!s->fsconf.tag) {
77         /* we haven't specified a mount_tag */
78         fprintf(stderr, "fsdev with id %s needs mount_tag arguments\n",
79                 s->fsconf.fsdev_id);
80         goto out;
81     }
82 
83     s->ctx.export_flags = fse->export_flags;
84     s->ctx.fs_root = g_strdup(fse->path);
85     s->ctx.exops.get_st_gen = NULL;
86     len = strlen(s->fsconf.tag);
87     if (len > MAX_TAG_LEN - 1) {
88         fprintf(stderr, "mount tag '%s' (%d bytes) is longer than "
89                 "maximum (%d bytes)", s->fsconf.tag, len, MAX_TAG_LEN - 1);
90         goto out;
91     }
92 
93     s->tag = g_strdup(s->fsconf.tag);
94     s->ctx.uid = -1;
95 
96     s->ops = fse->ops;
97     s->config_size = sizeof(struct virtio_9p_config) + len;
98     s->fid_list = NULL;
99     qemu_co_rwlock_init(&s->rename_lock);
100 
101     if (s->ops->init(&s->ctx) < 0) {
102         fprintf(stderr, "Virtio-9p Failed to initialize fs-driver with id:%s"
103                 " and export path:%s\n", s->fsconf.fsdev_id, s->ctx.fs_root);
104         goto out;
105     }
106     if (v9fs_init_worker_threads() < 0) {
107         fprintf(stderr, "worker thread initialization failed\n");
108         goto out;
109     }
110 
111     /*
112      * Check details of export path, We need to use fs driver
113      * call back to do that. Since we are in the init path, we don't
114      * use co-routines here.
115      */
116     if (s->ops->name_to_path(&s->ctx, NULL, "/", &path) < 0) {
117         fprintf(stderr,
118                 "error in converting name to path %s", strerror(errno));
119         goto out;
120     }
121     if (s->ops->lstat(&s->ctx, &path, &stat)) {
122         fprintf(stderr, "share path %s does not exist\n", fse->path);
123         goto out;
124     } else if (!S_ISDIR(stat.st_mode)) {
125         fprintf(stderr, "share path %s is not a directory\n", fse->path);
126         goto out;
127     }
128     v9fs_path_free(&path);
129 
130     return 0;
131 out:
132     g_free(s->ctx.fs_root);
133     g_free(s->tag);
134     virtio_cleanup(vdev);
135     v9fs_path_free(&path);
136 
137     return -1;
138 
139 }
140 
141 /* virtio-9p device */
142 
143 static Property virtio_9p_properties[] = {
144     DEFINE_VIRTIO_9P_PROPERTIES(V9fsState, fsconf),
145     DEFINE_PROP_END_OF_LIST(),
146 };
147 
148 static void virtio_9p_class_init(ObjectClass *klass, void *data)
149 {
150     DeviceClass *dc = DEVICE_CLASS(klass);
151     VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass);
152     dc->props = virtio_9p_properties;
153     set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
154     vdc->init = virtio_9p_device_init;
155     vdc->get_features = virtio_9p_get_features;
156     vdc->get_config = virtio_9p_get_config;
157 }
158 
159 static const TypeInfo virtio_device_info = {
160     .name = TYPE_VIRTIO_9P,
161     .parent = TYPE_VIRTIO_DEVICE,
162     .instance_size = sizeof(V9fsState),
163     .class_init = virtio_9p_class_init,
164 };
165 
166 static void virtio_9p_register_types(void)
167 {
168     type_register_static(&virtio_device_info);
169 }
170 
171 type_init(virtio_9p_register_types)
172