1 // Virtio block boot support.
2 //
3 // Copyright (C) 2010 Red Hat Inc.
4 //
5 // Authors:
6 //  Gleb Natapov <gnatapov@redhat.com>
7 //
8 // This file may be distributed under the terms of the GNU LGPLv3 license.
9 
10 #include "biosvar.h" // GET_GLOBALFLAT
11 #include "config.h" // CONFIG_*
12 #include "block.h" // struct drive_s
13 #include "malloc.h" // free
14 #include "output.h" // dprintf
15 #include "pcidevice.h" // foreachpci
16 #include "pci_ids.h" // PCI_DEVICE_ID_VIRTIO_BLK
17 #include "pci_regs.h" // PCI_VENDOR_ID
18 #include "stacks.h" // run_thread
19 #include "std/disk.h" // DISK_RET_SUCCESS
20 #include "string.h" // memset
21 #include "util.h" // usleep, bootprio_find_pci_device, is_bootprio_strict
22 #include "virtio-pci.h"
23 #include "virtio-mmio.h"
24 #include "virtio-ring.h"
25 #include "virtio-blk.h"
26 
27 struct virtiodrive_s {
28     struct drive_s drive;
29     struct vring_virtqueue *vq;
30     struct vp_device vp;
31 };
32 
33 static int
virtio_blk_op(struct disk_op_s * op,int write)34 virtio_blk_op(struct disk_op_s *op, int write)
35 {
36     struct virtiodrive_s *vdrive =
37         container_of(op->drive_fl, struct virtiodrive_s, drive);
38     struct vring_virtqueue *vq = vdrive->vq;
39     struct virtio_blk_outhdr hdr = {
40         .type = write ? VIRTIO_BLK_T_OUT : VIRTIO_BLK_T_IN,
41         .ioprio = 0,
42         .sector = op->lba,
43     };
44     u8 status = VIRTIO_BLK_S_UNSUPP;
45     struct vring_list sg[] = {
46         {
47             .addr       = (void*)(&hdr),
48             .length     = sizeof(hdr),
49         },
50         {
51             .addr       = op->buf_fl,
52             .length     = vdrive->drive.blksize * op->count,
53         },
54         {
55             .addr       = (void*)(&status),
56             .length     = sizeof(status),
57         },
58     };
59 
60     /* Add to virtqueue and kick host */
61     if (write)
62         vring_add_buf(vq, sg, 2, 1, 0, 0);
63     else
64         vring_add_buf(vq, sg, 1, 2, 0, 0);
65     vring_kick(&vdrive->vp, vq, 1);
66 
67     /* Wait for reply */
68     while (!vring_more_used(vq))
69         usleep(5);
70 
71     /* Reclaim virtqueue element */
72     vring_get_buf(vq, NULL);
73 
74     /* Clear interrupt status register.  Avoid leaving interrupts stuck if
75      * VRING_AVAIL_F_NO_INTERRUPT was ignored and interrupts were raised.
76      */
77     vp_get_isr(&vdrive->vp);
78 
79     return status == VIRTIO_BLK_S_OK ? DISK_RET_SUCCESS : DISK_RET_EBADTRACK;
80 }
81 
82 int
virtio_blk_process_op(struct disk_op_s * op)83 virtio_blk_process_op(struct disk_op_s *op)
84 {
85     if (! CONFIG_VIRTIO_BLK)
86         return 0;
87     switch (op->command) {
88     case CMD_READ:
89         return virtio_blk_op(op, 0);
90     case CMD_WRITE:
91         return virtio_blk_op(op, 1);
92     default:
93         return default_process_op(op);
94     }
95 }
96 
97 static void
init_virtio_blk(void * data)98 init_virtio_blk(void *data)
99 {
100     struct pci_device *pci = data;
101     u8 status = VIRTIO_CONFIG_S_ACKNOWLEDGE | VIRTIO_CONFIG_S_DRIVER;
102     dprintf(1, "found virtio-blk at %pP\n", pci);
103     struct virtiodrive_s *vdrive = malloc_low(sizeof(*vdrive));
104     if (!vdrive) {
105         warn_noalloc();
106         return;
107     }
108     memset(vdrive, 0, sizeof(*vdrive));
109     vdrive->drive.type = DTYPE_VIRTIO_BLK;
110     vdrive->drive.cntl_id = pci->bdf;
111 
112     vp_init_simple(&vdrive->vp, pci);
113     if (vp_find_vq(&vdrive->vp, 0, &vdrive->vq) < 0 ) {
114         dprintf(1, "fail to find vq for virtio-blk %pP\n", pci);
115         goto fail;
116     }
117 
118     if (vdrive->vp.use_modern) {
119         struct vp_device *vp = &vdrive->vp;
120         u64 features = vp_get_features(vp);
121         u64 version1 = 1ull << VIRTIO_F_VERSION_1;
122         u64 iommu_platform = 1ull << VIRTIO_F_IOMMU_PLATFORM;
123         u64 blk_size = 1ull << VIRTIO_BLK_F_BLK_SIZE;
124         if (!(features & version1)) {
125             dprintf(1, "modern device without virtio_1 feature bit: %pP\n", pci);
126             goto fail;
127         }
128 
129         features = features & (version1 | iommu_platform | blk_size);
130         vp_set_features(vp, features);
131         status |= VIRTIO_CONFIG_S_FEATURES_OK;
132         vp_set_status(vp, status);
133         if (!(vp_get_status(vp) & VIRTIO_CONFIG_S_FEATURES_OK)) {
134             dprintf(1, "device didn't accept features: %pP\n", pci);
135             goto fail;
136         }
137 
138         vdrive->drive.sectors =
139             vp_read(&vp->device, struct virtio_blk_config, capacity);
140         if (features & blk_size) {
141             vdrive->drive.blksize =
142                 vp_read(&vp->device, struct virtio_blk_config, blk_size);
143         } else {
144             vdrive->drive.blksize = DISK_SECTOR_SIZE;
145         }
146         if (vdrive->drive.blksize != DISK_SECTOR_SIZE) {
147             dprintf(1, "virtio-blk %pP block size %d is unsupported\n",
148                     pci, vdrive->drive.blksize);
149             goto fail;
150         }
151         dprintf(3, "virtio-blk %pP blksize=%d sectors=%u\n",
152                 pci, vdrive->drive.blksize, (u32)vdrive->drive.sectors);
153 
154         vdrive->drive.pchs.cylinder =
155             vp_read(&vp->device, struct virtio_blk_config, cylinders);
156         vdrive->drive.pchs.head =
157             vp_read(&vp->device, struct virtio_blk_config, heads);
158         vdrive->drive.pchs.sector =
159             vp_read(&vp->device, struct virtio_blk_config, sectors);
160     } else {
161         struct virtio_blk_config cfg;
162         vp_get_legacy(&vdrive->vp, 0, &cfg, sizeof(cfg));
163 
164         u64 f = vp_get_features(&vdrive->vp);
165         vdrive->drive.blksize = (f & (1 << VIRTIO_BLK_F_BLK_SIZE)) ?
166             cfg.blk_size : DISK_SECTOR_SIZE;
167 
168         vdrive->drive.sectors = cfg.capacity;
169         dprintf(3, "virtio-blk %pP blksize=%d sectors=%u\n",
170                 pci, vdrive->drive.blksize, (u32)vdrive->drive.sectors);
171 
172         if (vdrive->drive.blksize != DISK_SECTOR_SIZE) {
173             dprintf(1, "virtio-blk %pP block size %d is unsupported\n",
174                     pci, vdrive->drive.blksize);
175             goto fail;
176         }
177         vdrive->drive.pchs.cylinder = cfg.cylinders;
178         vdrive->drive.pchs.head = cfg.heads;
179         vdrive->drive.pchs.sector = cfg.sectors;
180     }
181 
182     char *desc = znprintf(MAXDESCSIZE, "Virtio disk PCI:%pP", pci);
183     boot_add_hd(&vdrive->drive, desc, bootprio_find_pci_device(pci));
184 
185     status |= VIRTIO_CONFIG_S_DRIVER_OK;
186     vp_set_status(&vdrive->vp, status);
187 
188     boot_lchs_find_pci_device(pci, &vdrive->drive.lchs);
189     return;
190 
191 fail:
192     vp_reset(&vdrive->vp);
193     free(vdrive->vq);
194     free(vdrive);
195 }
196 
197 void
init_virtio_blk_mmio(void * mmio)198 init_virtio_blk_mmio(void *mmio)
199 {
200     u8 status = VIRTIO_CONFIG_S_ACKNOWLEDGE | VIRTIO_CONFIG_S_DRIVER;
201     dprintf(1, "found virtio-blk-mmio at %p\n", mmio);
202     struct virtiodrive_s *vdrive = malloc_low(sizeof(*vdrive));
203     if (!vdrive) {
204         warn_noalloc();
205         return;
206     }
207     memset(vdrive, 0, sizeof(*vdrive));
208     vdrive->drive.type = DTYPE_VIRTIO_BLK;
209     vdrive->drive.cntl_id = (u32)mmio;
210 
211     vp_init_mmio(&vdrive->vp, mmio);
212     if (vp_find_vq(&vdrive->vp, 0, &vdrive->vq) < 0 ) {
213         dprintf(1, "fail to find vq for virtio-blk-mmio %p\n", mmio);
214         goto fail;
215     }
216 
217     struct vp_device *vp = &vdrive->vp;
218     u64 features = vp_get_features(vp);
219     u64 version1 = 1ull << VIRTIO_F_VERSION_1;
220     u64 blk_size = 1ull << VIRTIO_BLK_F_BLK_SIZE;
221 
222     features = features & (version1 | blk_size);
223     vp_set_features(vp, features);
224     status |= VIRTIO_CONFIG_S_FEATURES_OK;
225     vp_set_status(vp, status);
226     if (!(vp_get_status(vp) & VIRTIO_CONFIG_S_FEATURES_OK)) {
227         dprintf(1, "device didn't accept features: %p\n", mmio);
228         goto fail;
229     }
230 
231     vdrive->drive.sectors =
232         vp_read(&vp->device, struct virtio_blk_config, capacity);
233     if (features & blk_size) {
234         vdrive->drive.blksize =
235             vp_read(&vp->device, struct virtio_blk_config, blk_size);
236     } else {
237         vdrive->drive.blksize = DISK_SECTOR_SIZE;
238     }
239     if (vdrive->drive.blksize != DISK_SECTOR_SIZE) {
240         dprintf(1, "virtio-blk-mmio %p block size %d is unsupported\n",
241                 mmio, vdrive->drive.blksize);
242         goto fail;
243     }
244     dprintf(1, "virtio-blk-mmio %p blksize=%d sectors=%u\n",
245             mmio, vdrive->drive.blksize, (u32)vdrive->drive.sectors);
246 
247     vdrive->drive.pchs.cylinder =
248         vp_read(&vp->device, struct virtio_blk_config, cylinders);
249     vdrive->drive.pchs.head =
250         vp_read(&vp->device, struct virtio_blk_config, heads);
251     vdrive->drive.pchs.sector =
252         vp_read(&vp->device, struct virtio_blk_config, sectors);
253 
254     char *desc = znprintf(MAXDESCSIZE, "Virtio disk mmio:%p", mmio);
255     boot_add_hd(&vdrive->drive, desc, bootprio_find_mmio_device(mmio));
256 
257     status |= VIRTIO_CONFIG_S_DRIVER_OK;
258     vp_set_status(&vdrive->vp, status);
259     return;
260 
261 fail:
262     vp_reset(&vdrive->vp);
263     free(vdrive->vq);
264     free(vdrive);
265 }
266 
267 void
virtio_blk_setup(void)268 virtio_blk_setup(void)
269 {
270     u8 skip_nonbootable = is_bootprio_strict();
271 
272     ASSERT32FLAT();
273     if (! CONFIG_VIRTIO_BLK)
274         return;
275 
276     dprintf(3, "init virtio-blk\n");
277 
278     struct pci_device *pci;
279     foreachpci(pci) {
280         if (pci->vendor != PCI_VENDOR_ID_REDHAT_QUMRANET ||
281             (pci->device != PCI_DEVICE_ID_VIRTIO_BLK_09 &&
282              pci->device != PCI_DEVICE_ID_VIRTIO_BLK_10))
283             continue;
284 
285         if (skip_nonbootable && bootprio_find_pci_device(pci) < 0) {
286             dprintf(1, "skipping init of a non-bootable virtio-blk at %pP\n",
287                     pci);
288             continue;
289         }
290 
291         run_thread(init_virtio_blk, pci);
292     }
293 }
294