xref: /qemu/hw/9pfs/virtio-9p-device.c (revision 7cca27dfde6435a7846d88e8a1fa927d0ab99919)
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.h"
15 #include "hw/pc.h"
16 #include "qemu_socket.h"
17 #include "hw/virtio-pci.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     struct virtio_9p_config *cfg;
37     V9fsState *s = to_virtio_9p(vdev);
38 
39     cfg = g_malloc0(sizeof(struct virtio_9p_config) +
40                         s->tag_len);
41     stw_raw(&cfg->tag_len, s->tag_len);
42     memcpy(cfg->tag, s->tag, s->tag_len);
43     memcpy(config, cfg, s->config_size);
44     g_free(cfg);
45 }
46 
47 VirtIODevice *virtio_9p_init(DeviceState *dev, V9fsConf *conf)
48 {
49     V9fsState *s;
50     int i, len;
51     struct stat stat;
52     FsTypeEntry *fse;
53     V9fsPath path;
54 
55     s = (V9fsState *)virtio_common_init("virtio-9p",
56                                     VIRTIO_ID_9P,
57                                     sizeof(struct virtio_9p_config)+
58                                     MAX_TAG_LEN,
59                                     sizeof(V9fsState));
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(&s->vdev, MAX_REQ, handle_9p_output);
68 
69     fse = get_fsdev_fsentry(conf->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", conf->fsdev_id ? conf->fsdev_id : "NULL");
75         exit(1);
76     }
77 
78     if (!fse->path || !conf->tag) {
79         /* we haven't specified a mount_tag or the path */
80         fprintf(stderr, "fsdev with id %s needs path "
81                 "and Virtio-9p device needs mount_tag arguments\n",
82                 conf->fsdev_id);
83         exit(1);
84     }
85 
86     if (!strcmp(fse->security_model, "passthrough")) {
87         /* Files on the Fileserver set to client user credentials */
88         s->ctx.fs_sm = SM_PASSTHROUGH;
89         s->ctx.xops = passthrough_xattr_ops;
90     } else if (!strcmp(fse->security_model, "mapped")) {
91         /* Files on the fileserver are set to QEMU credentials.
92          * Client user credentials are saved in extended attributes.
93          */
94         s->ctx.fs_sm = SM_MAPPED;
95         s->ctx.xops = mapped_xattr_ops;
96     } else if (!strcmp(fse->security_model, "none")) {
97         /*
98          * Files on the fileserver are set to QEMU credentials.
99          */
100         s->ctx.fs_sm = SM_NONE;
101         s->ctx.xops = none_xattr_ops;
102     } else {
103         fprintf(stderr, "Default to security_model=none. You may want"
104                 " enable advanced security model using "
105                 "security option:\n\t security_model=passthrough\n\t "
106                 "security_model=mapped\n");
107         s->ctx.fs_sm = SM_NONE;
108         s->ctx.xops = none_xattr_ops;
109     }
110 
111     s->ctx.export_flags = fse->export_flags;
112     s->ctx.fs_root = g_strdup(fse->path);
113     s->ctx.exops.get_st_gen = NULL;
114 
115     len = strlen(conf->tag);
116     if (len > MAX_TAG_LEN) {
117         fprintf(stderr, "mount tag '%s' (%d bytes) is longer than "
118                 "maximum (%d bytes)", conf->tag, len, MAX_TAG_LEN);
119         exit(1);
120     }
121     /* s->tag is non-NULL terminated string */
122     s->tag = g_malloc(len);
123     memcpy(s->tag, conf->tag, len);
124     s->tag_len = len;
125     s->ctx.uid = -1;
126     s->ctx.flags = 0;
127 
128     s->ops = fse->ops;
129     s->vdev.get_features = virtio_9p_get_features;
130     s->config_size = sizeof(struct virtio_9p_config) + s->tag_len;
131     s->vdev.get_config = virtio_9p_get_config;
132     s->fid_list = NULL;
133     qemu_co_rwlock_init(&s->rename_lock);
134 
135     if (s->ops->init(&s->ctx) < 0) {
136         fprintf(stderr, "Virtio-9p Failed to initialize fs-driver with id:%s"
137                 " and export path:%s\n", conf->fsdev_id, s->ctx.fs_root);
138         exit(1);
139     }
140     if (v9fs_init_worker_threads() < 0) {
141         fprintf(stderr, "worker thread initialization failed\n");
142         exit(1);
143     }
144 
145     /*
146      * Check details of export path, We need to use fs driver
147      * call back to do that. Since we are in the init path, we don't
148      * use co-routines here.
149      */
150     v9fs_path_init(&path);
151     if (s->ops->name_to_path(&s->ctx, NULL, "/", &path) < 0) {
152         fprintf(stderr,
153                 "error in converting name to path %s", strerror(errno));
154         exit(1);
155     }
156     if (s->ops->lstat(&s->ctx, &path, &stat)) {
157         fprintf(stderr, "share path %s does not exist\n", fse->path);
158         exit(1);
159     } else if (!S_ISDIR(stat.st_mode)) {
160         fprintf(stderr, "share path %s is not a directory\n", fse->path);
161         exit(1);
162     }
163     v9fs_path_free(&path);
164 
165     return &s->vdev;
166 }
167 
168 static int virtio_9p_init_pci(PCIDevice *pci_dev)
169 {
170     VirtIOPCIProxy *proxy = DO_UPCAST(VirtIOPCIProxy, pci_dev, pci_dev);
171     VirtIODevice *vdev;
172 
173     vdev = virtio_9p_init(&pci_dev->qdev, &proxy->fsconf);
174     vdev->nvectors = proxy->nvectors;
175     virtio_init_pci(proxy, vdev);
176     /* make the actual value visible */
177     proxy->nvectors = vdev->nvectors;
178     return 0;
179 }
180 
181 static PCIDeviceInfo virtio_9p_info = {
182     .qdev.name = "virtio-9p-pci",
183     .qdev.size = sizeof(VirtIOPCIProxy),
184     .init      = virtio_9p_init_pci,
185     .vendor_id = PCI_VENDOR_ID_REDHAT_QUMRANET,
186     .device_id = 0x1009,
187     .revision  = VIRTIO_PCI_ABI_VERSION,
188     .class_id  = 0x2,
189     .qdev.props = (Property[]) {
190         DEFINE_PROP_BIT("ioeventfd", VirtIOPCIProxy, flags,
191                         VIRTIO_PCI_FLAG_USE_IOEVENTFD_BIT, true),
192         DEFINE_PROP_UINT32("vectors", VirtIOPCIProxy, nvectors, 2),
193         DEFINE_VIRTIO_COMMON_FEATURES(VirtIOPCIProxy, host_features),
194         DEFINE_PROP_STRING("mount_tag", VirtIOPCIProxy, fsconf.tag),
195         DEFINE_PROP_STRING("fsdev", VirtIOPCIProxy, fsconf.fsdev_id),
196         DEFINE_PROP_END_OF_LIST(),
197     }
198 };
199 
200 static void virtio_9p_register_devices(void)
201 {
202     pci_qdev_register(&virtio_9p_info);
203     virtio_9p_set_fd_limit();
204 }
205 
206 device_init(virtio_9p_register_devices)
207