Commit | Line | Data |
---|---|---|
2e04ef76 RR |
1 | /*P:100 |
2 | * This is the Launcher code, a simple program which lays out the "physical" | |
3 | * memory for the new Guest by mapping the kernel image and the virtual | |
4 | * devices, then opens /dev/lguest to tell the kernel about the Guest and | |
5 | * control it. | |
6 | :*/ | |
8ca47e00 RR |
7 | #define _LARGEFILE64_SOURCE |
8 | #define _GNU_SOURCE | |
9 | #include <stdio.h> | |
10 | #include <string.h> | |
11 | #include <unistd.h> | |
12 | #include <err.h> | |
13 | #include <stdint.h> | |
14 | #include <stdlib.h> | |
15 | #include <elf.h> | |
16 | #include <sys/mman.h> | |
6649bb7a | 17 | #include <sys/param.h> |
8ca47e00 RR |
18 | #include <sys/types.h> |
19 | #include <sys/stat.h> | |
20 | #include <sys/wait.h> | |
659a0e66 | 21 | #include <sys/eventfd.h> |
8ca47e00 RR |
22 | #include <fcntl.h> |
23 | #include <stdbool.h> | |
24 | #include <errno.h> | |
25 | #include <ctype.h> | |
26 | #include <sys/socket.h> | |
27 | #include <sys/ioctl.h> | |
28 | #include <sys/time.h> | |
29 | #include <time.h> | |
30 | #include <netinet/in.h> | |
31 | #include <net/if.h> | |
32 | #include <linux/sockios.h> | |
33 | #include <linux/if_tun.h> | |
34 | #include <sys/uio.h> | |
35 | #include <termios.h> | |
36 | #include <getopt.h> | |
17cbca2b RR |
37 | #include <assert.h> |
38 | #include <sched.h> | |
a586d4f6 RR |
39 | #include <limits.h> |
40 | #include <stddef.h> | |
a161883a | 41 | #include <signal.h> |
8aeb36e8 PS |
42 | #include <pwd.h> |
43 | #include <grp.h> | |
c565650b | 44 | #include <sys/user.h> |
d7fbf6e9 | 45 | #include <linux/pci_regs.h> |
8aeb36e8 | 46 | |
927cfb97 RR |
47 | #ifndef VIRTIO_F_ANY_LAYOUT |
48 | #define VIRTIO_F_ANY_LAYOUT 27 | |
49 | #endif | |
50 | ||
2e04ef76 | 51 | /*L:110 |
9f54288d | 52 | * We can ignore the 43 include files we need for this program, but I do want |
2e04ef76 | 53 | * to draw attention to the use of kernel-style types. |
db24e8c2 RR |
54 | * |
55 | * As Linus said, "C is a Spartan language, and so should your naming be." I | |
56 | * like these abbreviations, so we define them here. Note that u64 is always | |
57 | * unsigned long long, which works on all Linux systems: this means that we can | |
2e04ef76 RR |
58 | * use %llu in printf for any u64. |
59 | */ | |
db24e8c2 RR |
60 | typedef unsigned long long u64; |
61 | typedef uint32_t u32; | |
62 | typedef uint16_t u16; | |
63 | typedef uint8_t u8; | |
dde79789 | 64 | /*:*/ |
8ca47e00 | 65 | |
eb39f833 | 66 | #define VIRTIO_CONFIG_NO_LEGACY |
93153077 | 67 | #define VIRTIO_PCI_NO_LEGACY |
50516547 | 68 | #define VIRTIO_BLK_NO_LEGACY |
206ad06b | 69 | #define VIRTIO_NET_NO_LEGACY |
93153077 RR |
70 | |
71 | /* Use in-kernel ones, which defines VIRTIO_F_VERSION_1 */ | |
72 | #include "../../include/uapi/linux/virtio_config.h" | |
bf6d4034 | 73 | #include "../../include/uapi/linux/virtio_net.h" |
50516547 | 74 | #include "../../include/uapi/linux/virtio_blk.h" |
e8330d9b | 75 | #include "../../include/uapi/linux/virtio_console.h" |
0d5b5d39 | 76 | #include "../../include/uapi/linux/virtio_rng.h" |
e6dc0418 | 77 | #include <linux/virtio_ring.h> |
93153077 | 78 | #include "../../include/uapi/linux/virtio_pci.h" |
e6dc0418 RR |
79 | #include <asm/bootparam.h> |
80 | #include "../../include/linux/lguest_launcher.h" | |
81 | ||
8ca47e00 RR |
82 | #define BRIDGE_PFX "bridge:" |
83 | #ifndef SIOCBRADDIF | |
84 | #define SIOCBRADDIF 0x89a2 /* add interface to bridge */ | |
85 | #endif | |
3c6b5bfa RR |
86 | /* We can have up to 256 pages for devices. */ |
87 | #define DEVICE_PAGES 256 | |
0f0c4fab RR |
88 | /* This will occupy 3 pages: it must be a power of 2. */ |
89 | #define VIRTQUEUE_NUM 256 | |
8ca47e00 | 90 | |
2e04ef76 RR |
91 | /*L:120 |
92 | * verbose is both a global flag and a macro. The C preprocessor allows | |
93 | * this, and although I wouldn't recommend it, it works quite nicely here. | |
94 | */ | |
8ca47e00 RR |
95 | static bool verbose; |
96 | #define verbose(args...) \ | |
97 | do { if (verbose) printf(args); } while(0) | |
dde79789 RR |
98 | /*:*/ |
99 | ||
3c6b5bfa RR |
100 | /* The pointer to the start of guest memory. */ |
101 | static void *guest_base; | |
102 | /* The maximum guest physical address allowed, and maximum possible. */ | |
0a6bcc18 | 103 | static unsigned long guest_limit, guest_max, guest_mmio; |
56739c80 RR |
104 | /* The /dev/lguest file descriptor. */ |
105 | static int lguest_fd; | |
8ca47e00 | 106 | |
e3283fa0 GOC |
107 | /* a per-cpu variable indicating whose vcpu is currently running */ |
108 | static unsigned int __thread cpu_id; | |
109 | ||
6a54f9ab RR |
110 | /* 5 bit device number in the PCI_CONFIG_ADDR => 32 only */ |
111 | #define MAX_PCI_DEVICES 32 | |
112 | ||
dde79789 | 113 | /* This is our list of devices. */ |
1842f23c | 114 | struct device_list { |
17cbca2b RR |
115 | /* Counter to assign interrupt numbers. */ |
116 | unsigned int next_irq; | |
117 | ||
118 | /* Counter to print out convenient device numbers. */ | |
119 | unsigned int device_num; | |
120 | ||
6a54f9ab RR |
121 | /* PCI devices. */ |
122 | struct device *pci[MAX_PCI_DEVICES]; | |
8ca47e00 RR |
123 | }; |
124 | ||
17cbca2b RR |
125 | /* The list of Guest devices, based on command line arguments. */ |
126 | static struct device_list devices; | |
127 | ||
e523caa6 RR |
128 | /* |
129 | * Just like struct virtio_pci_cfg_cap in uapi/linux/virtio_pci.h, | |
130 | * but uses a u32 explicitly for the data. | |
131 | */ | |
132 | struct virtio_pci_cfg_cap_u32 { | |
93153077 | 133 | struct virtio_pci_cap cap; |
b2ce1ea4 | 134 | u32 pci_cfg_data; /* Data for BAR access. */ |
93153077 RR |
135 | }; |
136 | ||
137 | struct virtio_pci_mmio { | |
138 | struct virtio_pci_common_cfg cfg; | |
139 | u16 notify; | |
140 | u8 isr; | |
141 | u8 padding; | |
142 | /* Device-specific configuration follows this. */ | |
143 | }; | |
144 | ||
d7fbf6e9 RR |
145 | /* This is the layout (little-endian) of the PCI config space. */ |
146 | struct pci_config { | |
147 | u16 vendor_id, device_id; | |
148 | u16 command, status; | |
149 | u8 revid, prog_if, subclass, class; | |
150 | u8 cacheline_size, lat_timer, header_type, bist; | |
151 | u32 bar[6]; | |
152 | u32 cardbus_cis_ptr; | |
153 | u16 subsystem_vendor_id, subsystem_device_id; | |
154 | u32 expansion_rom_addr; | |
155 | u8 capabilities, reserved1[3]; | |
156 | u32 reserved2; | |
157 | u8 irq_line, irq_pin, min_grant, max_latency; | |
93153077 RR |
158 | |
159 | /* Now, this is the linked capability list. */ | |
160 | struct virtio_pci_cap common; | |
161 | struct virtio_pci_notify_cap notify; | |
162 | struct virtio_pci_cap isr; | |
163 | struct virtio_pci_cap device; | |
e523caa6 | 164 | struct virtio_pci_cfg_cap_u32 cfg_access; |
d7fbf6e9 RR |
165 | }; |
166 | ||
dde79789 | 167 | /* The device structure describes a single device. */ |
1842f23c | 168 | struct device { |
17cbca2b RR |
169 | /* The name of this device, for --verbose. */ |
170 | const char *name; | |
8ca47e00 | 171 | |
17cbca2b RR |
172 | /* Any queues attached to this device */ |
173 | struct virtqueue *vq; | |
8ca47e00 | 174 | |
659a0e66 RR |
175 | /* Is it operational */ |
176 | bool running; | |
a007a751 | 177 | |
d39a6785 RR |
178 | /* Has it written FEATURES_OK but not re-checked it? */ |
179 | bool wrote_features_ok; | |
180 | ||
d7fbf6e9 RR |
181 | /* PCI configuration */ |
182 | union { | |
183 | struct pci_config config; | |
184 | u32 config_words[sizeof(struct pci_config) / sizeof(u32)]; | |
185 | }; | |
186 | ||
93153077 RR |
187 | /* Features we offer, and those accepted. */ |
188 | u64 features, features_accepted; | |
189 | ||
d7fbf6e9 RR |
190 | /* Device-specific config hangs off the end of this. */ |
191 | struct virtio_pci_mmio *mmio; | |
192 | ||
6a54f9ab RR |
193 | /* PCI MMIO resources (all in BAR0) */ |
194 | size_t mmio_size; | |
195 | u32 mmio_addr; | |
196 | ||
8ca47e00 RR |
197 | /* Device-specific data. */ |
198 | void *priv; | |
199 | }; | |
200 | ||
17cbca2b | 201 | /* The virtqueue structure describes a queue attached to a device. */ |
1842f23c | 202 | struct virtqueue { |
17cbca2b RR |
203 | struct virtqueue *next; |
204 | ||
205 | /* Which device owns me. */ | |
206 | struct device *dev; | |
207 | ||
17c56d6d RR |
208 | /* Name for printing errors. */ |
209 | const char *name; | |
210 | ||
17cbca2b RR |
211 | /* The actual ring of buffers. */ |
212 | struct vring vring; | |
213 | ||
93153077 RR |
214 | /* The information about this virtqueue (we only use queue_size on) */ |
215 | struct virtio_pci_common_cfg pci_config; | |
216 | ||
17cbca2b RR |
217 | /* Last available index we saw. */ |
218 | u16 last_avail_idx; | |
219 | ||
95c517c0 RR |
220 | /* How many are used since we sent last irq? */ |
221 | unsigned int pending_used; | |
222 | ||
659a0e66 RR |
223 | /* Eventfd where Guest notifications arrive. */ |
224 | int eventfd; | |
20887611 | 225 | |
659a0e66 RR |
226 | /* Function for the thread which is servicing this virtqueue. */ |
227 | void (*service)(struct virtqueue *vq); | |
228 | pid_t thread; | |
17cbca2b RR |
229 | }; |
230 | ||
ec04b13f BR |
231 | /* Remember the arguments to the program so we can "reboot" */ |
232 | static char **main_args; | |
233 | ||
659a0e66 RR |
234 | /* The original tty settings to restore on exit. */ |
235 | static struct termios orig_term; | |
236 | ||
2e04ef76 RR |
237 | /* |
238 | * We have to be careful with barriers: our devices are all run in separate | |
f7027c63 | 239 | * threads and so we need to make sure that changes visible to the Guest happen |
2e04ef76 RR |
240 | * in precise order. |
241 | */ | |
f7027c63 | 242 | #define wmb() __asm__ __volatile__("" : : : "memory") |
0d69a65e RR |
243 | #define rmb() __asm__ __volatile__("lock; addl $0,0(%%esp)" : : : "memory") |
244 | #define mb() __asm__ __volatile__("lock; addl $0,0(%%esp)" : : : "memory") | |
17cbca2b | 245 | |
b5111790 RR |
246 | /* Wrapper for the last available index. Makes it easier to change. */ |
247 | #define lg_last_avail(vq) ((vq)->last_avail_idx) | |
248 | ||
2e04ef76 RR |
249 | /* |
250 | * The virtio configuration space is defined to be little-endian. x86 is | |
251 | * little-endian too, but it's nice to be explicit so we have these helpers. | |
252 | */ | |
17cbca2b RR |
253 | #define cpu_to_le16(v16) (v16) |
254 | #define cpu_to_le32(v32) (v32) | |
255 | #define cpu_to_le64(v64) (v64) | |
256 | #define le16_to_cpu(v16) (v16) | |
257 | #define le32_to_cpu(v32) (v32) | |
a586d4f6 | 258 | #define le64_to_cpu(v64) (v64) |
17cbca2b | 259 | |
1e1c17a7 RR |
260 | /* |
261 | * A real device would ignore weird/non-compliant driver behaviour. We | |
262 | * stop and flag it, to help debugging Linux problems. | |
263 | */ | |
264 | #define bad_driver(d, fmt, ...) \ | |
265 | errx(1, "%s: bad driver: " fmt, (d)->name, ## __VA_ARGS__) | |
266 | #define bad_driver_vq(vq, fmt, ...) \ | |
267 | errx(1, "%s vq %s: bad driver: " fmt, (vq)->dev->name, \ | |
268 | vq->name, ## __VA_ARGS__) | |
269 | ||
28fd6d7f RR |
270 | /* Is this iovec empty? */ |
271 | static bool iov_empty(const struct iovec iov[], unsigned int num_iov) | |
272 | { | |
273 | unsigned int i; | |
274 | ||
275 | for (i = 0; i < num_iov; i++) | |
276 | if (iov[i].iov_len) | |
277 | return false; | |
278 | return true; | |
279 | } | |
280 | ||
281 | /* Take len bytes from the front of this iovec. */ | |
1e1c17a7 RR |
282 | static void iov_consume(struct device *d, |
283 | struct iovec iov[], unsigned num_iov, | |
c0316a94 | 284 | void *dest, unsigned len) |
28fd6d7f RR |
285 | { |
286 | unsigned int i; | |
287 | ||
288 | for (i = 0; i < num_iov; i++) { | |
289 | unsigned int used; | |
290 | ||
291 | used = iov[i].iov_len < len ? iov[i].iov_len : len; | |
c0316a94 RR |
292 | if (dest) { |
293 | memcpy(dest, iov[i].iov_base, used); | |
294 | dest += used; | |
295 | } | |
28fd6d7f RR |
296 | iov[i].iov_base += used; |
297 | iov[i].iov_len -= used; | |
298 | len -= used; | |
299 | } | |
c0316a94 | 300 | if (len != 0) |
1e1c17a7 | 301 | bad_driver(d, "iovec too short!"); |
28fd6d7f RR |
302 | } |
303 | ||
2e04ef76 RR |
304 | /*L:100 |
305 | * The Launcher code itself takes us out into userspace, that scary place where | |
306 | * pointers run wild and free! Unfortunately, like most userspace programs, | |
307 | * it's quite boring (which is why everyone likes to hack on the kernel!). | |
308 | * Perhaps if you make up an Lguest Drinking Game at this point, it will get | |
309 | * you through this section. Or, maybe not. | |
3c6b5bfa RR |
310 | * |
311 | * The Launcher sets up a big chunk of memory to be the Guest's "physical" | |
312 | * memory and stores it in "guest_base". In other words, Guest physical == | |
313 | * Launcher virtual with an offset. | |
314 | * | |
315 | * This can be tough to get your head around, but usually it just means that we | |
a33f3224 | 316 | * use these trivial conversion functions when the Guest gives us its |
2e04ef76 RR |
317 | * "physical" addresses: |
318 | */ | |
3c6b5bfa RR |
319 | static void *from_guest_phys(unsigned long addr) |
320 | { | |
321 | return guest_base + addr; | |
322 | } | |
323 | ||
324 | static unsigned long to_guest_phys(const void *addr) | |
325 | { | |
326 | return (addr - guest_base); | |
327 | } | |
328 | ||
dde79789 RR |
329 | /*L:130 |
330 | * Loading the Kernel. | |
331 | * | |
332 | * We start with couple of simple helper routines. open_or_die() avoids | |
2e04ef76 RR |
333 | * error-checking code cluttering the callers: |
334 | */ | |
8ca47e00 RR |
335 | static int open_or_die(const char *name, int flags) |
336 | { | |
337 | int fd = open(name, flags); | |
338 | if (fd < 0) | |
339 | err(1, "Failed to open %s", name); | |
340 | return fd; | |
341 | } | |
342 | ||
3c6b5bfa RR |
343 | /* map_zeroed_pages() takes a number of pages. */ |
344 | static void *map_zeroed_pages(unsigned int num) | |
8ca47e00 | 345 | { |
3c6b5bfa RR |
346 | int fd = open_or_die("/dev/zero", O_RDONLY); |
347 | void *addr; | |
8ca47e00 | 348 | |
2e04ef76 RR |
349 | /* |
350 | * We use a private mapping (ie. if we write to the page, it will be | |
5230ff0c PS |
351 | * copied). We allocate an extra two pages PROT_NONE to act as guard |
352 | * pages against read/write attempts that exceed allocated space. | |
2e04ef76 | 353 | */ |
5230ff0c PS |
354 | addr = mmap(NULL, getpagesize() * (num+2), |
355 | PROT_NONE, MAP_PRIVATE, fd, 0); | |
356 | ||
3c6b5bfa | 357 | if (addr == MAP_FAILED) |
af901ca1 | 358 | err(1, "Mmapping %u pages of /dev/zero", num); |
a91d74a3 | 359 | |
5230ff0c PS |
360 | if (mprotect(addr + getpagesize(), getpagesize() * num, |
361 | PROT_READ|PROT_WRITE) == -1) | |
362 | err(1, "mprotect rw %u pages failed", num); | |
363 | ||
a91d74a3 RR |
364 | /* |
365 | * One neat mmap feature is that you can close the fd, and it | |
366 | * stays mapped. | |
367 | */ | |
34bdaab4 | 368 | close(fd); |
3c6b5bfa | 369 | |
5230ff0c PS |
370 | /* Return address after PROT_NONE page */ |
371 | return addr + getpagesize(); | |
3c6b5bfa RR |
372 | } |
373 | ||
0a6bcc18 RR |
374 | /* Get some bytes which won't be mapped into the guest. */ |
375 | static unsigned long get_mmio_region(size_t size) | |
376 | { | |
377 | unsigned long addr = guest_mmio; | |
378 | size_t i; | |
379 | ||
380 | if (!size) | |
381 | return addr; | |
382 | ||
383 | /* Size has to be a power of 2 (and multiple of 16) */ | |
384 | for (i = 1; i < size; i <<= 1); | |
385 | ||
386 | guest_mmio += i; | |
387 | ||
388 | return addr; | |
389 | } | |
390 | ||
2e04ef76 RR |
391 | /* |
392 | * This routine is used to load the kernel or initrd. It tries mmap, but if | |
6649bb7a | 393 | * that fails (Plan 9's kernel file isn't nicely aligned on page boundaries), |
2e04ef76 RR |
394 | * it falls back to reading the memory in. |
395 | */ | |
6649bb7a RM |
396 | static void map_at(int fd, void *addr, unsigned long offset, unsigned long len) |
397 | { | |
398 | ssize_t r; | |
399 | ||
2e04ef76 RR |
400 | /* |
401 | * We map writable even though for some segments are marked read-only. | |
6649bb7a RM |
402 | * The kernel really wants to be writable: it patches its own |
403 | * instructions. | |
404 | * | |
405 | * MAP_PRIVATE means that the page won't be copied until a write is | |
406 | * done to it. This allows us to share untouched memory between | |
2e04ef76 RR |
407 | * Guests. |
408 | */ | |
5230ff0c | 409 | if (mmap(addr, len, PROT_READ|PROT_WRITE, |
6649bb7a RM |
410 | MAP_FIXED|MAP_PRIVATE, fd, offset) != MAP_FAILED) |
411 | return; | |
412 | ||
413 | /* pread does a seek and a read in one shot: saves a few lines. */ | |
414 | r = pread(fd, addr, len, offset); | |
415 | if (r != len) | |
416 | err(1, "Reading offset %lu len %lu gave %zi", offset, len, r); | |
417 | } | |
418 | ||
2e04ef76 RR |
419 | /* |
420 | * This routine takes an open vmlinux image, which is in ELF, and maps it into | |
dde79789 RR |
421 | * the Guest memory. ELF = Embedded Linking Format, which is the format used |
422 | * by all modern binaries on Linux including the kernel. | |
423 | * | |
424 | * The ELF headers give *two* addresses: a physical address, and a virtual | |
47436aa4 RR |
425 | * address. We use the physical address; the Guest will map itself to the |
426 | * virtual address. | |
dde79789 | 427 | * |
2e04ef76 RR |
428 | * We return the starting address. |
429 | */ | |
47436aa4 | 430 | static unsigned long map_elf(int elf_fd, const Elf32_Ehdr *ehdr) |
8ca47e00 | 431 | { |
8ca47e00 RR |
432 | Elf32_Phdr phdr[ehdr->e_phnum]; |
433 | unsigned int i; | |
8ca47e00 | 434 | |
2e04ef76 RR |
435 | /* |
436 | * Sanity checks on the main ELF header: an x86 executable with a | |
437 | * reasonable number of correctly-sized program headers. | |
438 | */ | |
8ca47e00 RR |
439 | if (ehdr->e_type != ET_EXEC |
440 | || ehdr->e_machine != EM_386 | |
441 | || ehdr->e_phentsize != sizeof(Elf32_Phdr) | |
442 | || ehdr->e_phnum < 1 || ehdr->e_phnum > 65536U/sizeof(Elf32_Phdr)) | |
443 | errx(1, "Malformed elf header"); | |
444 | ||
2e04ef76 RR |
445 | /* |
446 | * An ELF executable contains an ELF header and a number of "program" | |
dde79789 | 447 | * headers which indicate which parts ("segments") of the program to |
2e04ef76 RR |
448 | * load where. |
449 | */ | |
dde79789 RR |
450 | |
451 | /* We read in all the program headers at once: */ | |
8ca47e00 RR |
452 | if (lseek(elf_fd, ehdr->e_phoff, SEEK_SET) < 0) |
453 | err(1, "Seeking to program headers"); | |
454 | if (read(elf_fd, phdr, sizeof(phdr)) != sizeof(phdr)) | |
455 | err(1, "Reading program headers"); | |
456 | ||
2e04ef76 RR |
457 | /* |
458 | * Try all the headers: there are usually only three. A read-only one, | |
459 | * a read-write one, and a "note" section which we don't load. | |
460 | */ | |
8ca47e00 | 461 | for (i = 0; i < ehdr->e_phnum; i++) { |
dde79789 | 462 | /* If this isn't a loadable segment, we ignore it */ |
8ca47e00 RR |
463 | if (phdr[i].p_type != PT_LOAD) |
464 | continue; | |
465 | ||
466 | verbose("Section %i: size %i addr %p\n", | |
467 | i, phdr[i].p_memsz, (void *)phdr[i].p_paddr); | |
468 | ||
6649bb7a | 469 | /* We map this section of the file at its physical address. */ |
3c6b5bfa | 470 | map_at(elf_fd, from_guest_phys(phdr[i].p_paddr), |
6649bb7a | 471 | phdr[i].p_offset, phdr[i].p_filesz); |
8ca47e00 RR |
472 | } |
473 | ||
814a0e5c RR |
474 | /* The entry point is given in the ELF header. */ |
475 | return ehdr->e_entry; | |
8ca47e00 RR |
476 | } |
477 | ||
2e04ef76 RR |
478 | /*L:150 |
479 | * A bzImage, unlike an ELF file, is not meant to be loaded. You're supposed | |
480 | * to jump into it and it will unpack itself. We used to have to perform some | |
481 | * hairy magic because the unpacking code scared me. | |
dde79789 | 482 | * |
5bbf89fc RR |
483 | * Fortunately, Jeremy Fitzhardinge convinced me it wasn't that hard and wrote |
484 | * a small patch to jump over the tricky bits in the Guest, so now we just read | |
2e04ef76 RR |
485 | * the funky header so we know where in the file to load, and away we go! |
486 | */ | |
47436aa4 | 487 | static unsigned long load_bzimage(int fd) |
8ca47e00 | 488 | { |
43d33b21 | 489 | struct boot_params boot; |
5bbf89fc RR |
490 | int r; |
491 | /* Modern bzImages get loaded at 1M. */ | |
492 | void *p = from_guest_phys(0x100000); | |
493 | ||
2e04ef76 RR |
494 | /* |
495 | * Go back to the start of the file and read the header. It should be | |
395cf969 | 496 | * a Linux boot header (see Documentation/x86/boot.txt) |
2e04ef76 | 497 | */ |
5bbf89fc | 498 | lseek(fd, 0, SEEK_SET); |
43d33b21 | 499 | read(fd, &boot, sizeof(boot)); |
5bbf89fc | 500 | |
43d33b21 RR |
501 | /* Inside the setup_hdr, we expect the magic "HdrS" */ |
502 | if (memcmp(&boot.hdr.header, "HdrS", 4) != 0) | |
5bbf89fc RR |
503 | errx(1, "This doesn't look like a bzImage to me"); |
504 | ||
43d33b21 RR |
505 | /* Skip over the extra sectors of the header. */ |
506 | lseek(fd, (boot.hdr.setup_sects+1) * 512, SEEK_SET); | |
5bbf89fc RR |
507 | |
508 | /* Now read everything into memory. in nice big chunks. */ | |
509 | while ((r = read(fd, p, 65536)) > 0) | |
510 | p += r; | |
511 | ||
43d33b21 RR |
512 | /* Finally, code32_start tells us where to enter the kernel. */ |
513 | return boot.hdr.code32_start; | |
8ca47e00 RR |
514 | } |
515 | ||
2e04ef76 RR |
516 | /*L:140 |
517 | * Loading the kernel is easy when it's a "vmlinux", but most kernels | |
e1e72965 | 518 | * come wrapped up in the self-decompressing "bzImage" format. With a little |
2e04ef76 RR |
519 | * work, we can load those, too. |
520 | */ | |
47436aa4 | 521 | static unsigned long load_kernel(int fd) |
8ca47e00 RR |
522 | { |
523 | Elf32_Ehdr hdr; | |
524 | ||
dde79789 | 525 | /* Read in the first few bytes. */ |
8ca47e00 RR |
526 | if (read(fd, &hdr, sizeof(hdr)) != sizeof(hdr)) |
527 | err(1, "Reading kernel"); | |
528 | ||
dde79789 | 529 | /* If it's an ELF file, it starts with "\177ELF" */ |
8ca47e00 | 530 | if (memcmp(hdr.e_ident, ELFMAG, SELFMAG) == 0) |
47436aa4 | 531 | return map_elf(fd, &hdr); |
8ca47e00 | 532 | |
a6bd8e13 | 533 | /* Otherwise we assume it's a bzImage, and try to load it. */ |
47436aa4 | 534 | return load_bzimage(fd); |
8ca47e00 RR |
535 | } |
536 | ||
2e04ef76 RR |
537 | /* |
538 | * This is a trivial little helper to align pages. Andi Kleen hated it because | |
dde79789 RR |
539 | * it calls getpagesize() twice: "it's dumb code." |
540 | * | |
541 | * Kernel guys get really het up about optimization, even when it's not | |
2e04ef76 RR |
542 | * necessary. I leave this code as a reaction against that. |
543 | */ | |
8ca47e00 RR |
544 | static inline unsigned long page_align(unsigned long addr) |
545 | { | |
dde79789 | 546 | /* Add upwards and truncate downwards. */ |
8ca47e00 RR |
547 | return ((addr + getpagesize()-1) & ~(getpagesize()-1)); |
548 | } | |
549 | ||
2e04ef76 RR |
550 | /*L:180 |
551 | * An "initial ram disk" is a disk image loaded into memory along with the | |
552 | * kernel which the kernel can use to boot from without needing any drivers. | |
553 | * Most distributions now use this as standard: the initrd contains the code to | |
554 | * load the appropriate driver modules for the current machine. | |
dde79789 RR |
555 | * |
556 | * Importantly, James Morris works for RedHat, and Fedora uses initrds for its | |
2e04ef76 RR |
557 | * kernels. He sent me this (and tells me when I break it). |
558 | */ | |
8ca47e00 RR |
559 | static unsigned long load_initrd(const char *name, unsigned long mem) |
560 | { | |
561 | int ifd; | |
562 | struct stat st; | |
563 | unsigned long len; | |
8ca47e00 RR |
564 | |
565 | ifd = open_or_die(name, O_RDONLY); | |
dde79789 | 566 | /* fstat() is needed to get the file size. */ |
8ca47e00 RR |
567 | if (fstat(ifd, &st) < 0) |
568 | err(1, "fstat() on initrd '%s'", name); | |
569 | ||
2e04ef76 RR |
570 | /* |
571 | * We map the initrd at the top of memory, but mmap wants it to be | |
572 | * page-aligned, so we round the size up for that. | |
573 | */ | |
8ca47e00 | 574 | len = page_align(st.st_size); |
3c6b5bfa | 575 | map_at(ifd, from_guest_phys(mem - len), 0, st.st_size); |
2e04ef76 RR |
576 | /* |
577 | * Once a file is mapped, you can close the file descriptor. It's a | |
578 | * little odd, but quite useful. | |
579 | */ | |
8ca47e00 | 580 | close(ifd); |
6649bb7a | 581 | verbose("mapped initrd %s size=%lu @ %p\n", name, len, (void*)mem-len); |
dde79789 RR |
582 | |
583 | /* We return the initrd size. */ | |
8ca47e00 RR |
584 | return len; |
585 | } | |
e1e72965 | 586 | /*:*/ |
8ca47e00 | 587 | |
2e04ef76 RR |
588 | /* |
589 | * Simple routine to roll all the commandline arguments together with spaces | |
590 | * between them. | |
591 | */ | |
8ca47e00 RR |
592 | static void concat(char *dst, char *args[]) |
593 | { | |
594 | unsigned int i, len = 0; | |
595 | ||
596 | for (i = 0; args[i]; i++) { | |
1ef36fa6 PB |
597 | if (i) { |
598 | strcat(dst+len, " "); | |
599 | len++; | |
600 | } | |
8ca47e00 | 601 | strcpy(dst+len, args[i]); |
1ef36fa6 | 602 | len += strlen(args[i]); |
8ca47e00 RR |
603 | } |
604 | /* In case it's empty. */ | |
605 | dst[len] = '\0'; | |
606 | } | |
607 | ||
2e04ef76 RR |
608 | /*L:185 |
609 | * This is where we actually tell the kernel to initialize the Guest. We | |
e1e72965 | 610 | * saw the arguments it expects when we looked at initialize() in lguest_user.c: |
58a24566 | 611 | * the base of Guest "physical" memory, the top physical page to allow and the |
2e04ef76 RR |
612 | * entry point for the Guest. |
613 | */ | |
56739c80 | 614 | static void tell_kernel(unsigned long start) |
8ca47e00 | 615 | { |
511801dc JS |
616 | unsigned long args[] = { LHREQ_INITIALIZE, |
617 | (unsigned long)guest_base, | |
7313d521 | 618 | guest_limit / getpagesize(), start, |
0a6bcc18 RR |
619 | (guest_mmio+getpagesize()-1) / getpagesize() }; |
620 | verbose("Guest: %p - %p (%#lx, MMIO %#lx)\n", | |
621 | guest_base, guest_base + guest_limit, | |
622 | guest_limit, guest_mmio); | |
56739c80 RR |
623 | lguest_fd = open_or_die("/dev/lguest", O_RDWR); |
624 | if (write(lguest_fd, args, sizeof(args)) < 0) | |
8ca47e00 | 625 | err(1, "Writing to /dev/lguest"); |
8ca47e00 | 626 | } |
dde79789 | 627 | /*:*/ |
8ca47e00 | 628 | |
a91d74a3 | 629 | /*L:200 |
dde79789 RR |
630 | * Device Handling. |
631 | * | |
e1e72965 | 632 | * When the Guest gives us a buffer, it sends an array of addresses and sizes. |
dde79789 | 633 | * We need to make sure it's not trying to reach into the Launcher itself, so |
e1e72965 | 634 | * we have a convenient routine which checks it and exits with an error message |
dde79789 RR |
635 | * if something funny is going on: |
636 | */ | |
1e1c17a7 RR |
637 | static void *_check_pointer(struct device *d, |
638 | unsigned long addr, unsigned int size, | |
8ca47e00 RR |
639 | unsigned int line) |
640 | { | |
2e04ef76 | 641 | /* |
5230ff0c PS |
642 | * Check if the requested address and size exceeds the allocated memory, |
643 | * or addr + size wraps around. | |
2e04ef76 | 644 | */ |
5230ff0c | 645 | if ((addr + size) > guest_limit || (addr + size) < addr) |
1e1c17a7 RR |
646 | bad_driver(d, "%s:%i: Invalid address %#lx", |
647 | __FILE__, line, addr); | |
2e04ef76 RR |
648 | /* |
649 | * We return a pointer for the caller's convenience, now we know it's | |
650 | * safe to use. | |
651 | */ | |
3c6b5bfa | 652 | return from_guest_phys(addr); |
8ca47e00 | 653 | } |
dde79789 | 654 | /* A macro which transparently hands the line number to the real function. */ |
1e1c17a7 | 655 | #define check_pointer(d,addr,size) _check_pointer(d, addr, size, __LINE__) |
8ca47e00 | 656 | |
2e04ef76 RR |
657 | /* |
658 | * Each buffer in the virtqueues is actually a chain of descriptors. This | |
e1e72965 | 659 | * function returns the next descriptor in the chain, or vq->vring.num if we're |
2e04ef76 RR |
660 | * at the end. |
661 | */ | |
1e1c17a7 | 662 | static unsigned next_desc(struct device *d, struct vring_desc *desc, |
d1f0132e | 663 | unsigned int i, unsigned int max) |
17cbca2b RR |
664 | { |
665 | unsigned int next; | |
666 | ||
667 | /* If this descriptor says it doesn't chain, we're done. */ | |
d1f0132e MM |
668 | if (!(desc[i].flags & VRING_DESC_F_NEXT)) |
669 | return max; | |
17cbca2b RR |
670 | |
671 | /* Check they're not leading us off end of descriptors. */ | |
d1f0132e | 672 | next = desc[i].next; |
17cbca2b RR |
673 | /* Make sure compiler knows to grab that: we don't want it changing! */ |
674 | wmb(); | |
675 | ||
d1f0132e | 676 | if (next >= max) |
1e1c17a7 | 677 | bad_driver(d, "Desc next is %u", next); |
17cbca2b RR |
678 | |
679 | return next; | |
680 | } | |
681 | ||
a91d74a3 RR |
682 | /* |
683 | * This actually sends the interrupt for this virtqueue, if we've used a | |
684 | * buffer. | |
685 | */ | |
38bc2b8c RR |
686 | static void trigger_irq(struct virtqueue *vq) |
687 | { | |
d9028eda | 688 | unsigned long buf[] = { LHREQ_IRQ, vq->dev->config.irq_line }; |
38bc2b8c | 689 | |
95c517c0 RR |
690 | /* Don't inform them if nothing used. */ |
691 | if (!vq->pending_used) | |
692 | return; | |
693 | vq->pending_used = 0; | |
694 | ||
d39a6785 RR |
695 | /* |
696 | * 2.4.7.1: | |
697 | * | |
698 | * If the VIRTIO_F_EVENT_IDX feature bit is not negotiated: | |
699 | * The driver MUST set flags to 0 or 1. | |
700 | */ | |
701 | if (vq->vring.avail->flags > 1) | |
1e1c17a7 | 702 | bad_driver_vq(vq, "avail->flags = %u\n", vq->vring.avail->flags); |
d39a6785 RR |
703 | |
704 | /* | |
705 | * 2.4.7.2: | |
706 | * | |
707 | * If the VIRTIO_F_EVENT_IDX feature bit is not negotiated: | |
708 | * | |
709 | * - The device MUST ignore the used_event value. | |
710 | * - After the device writes a descriptor index into the used ring: | |
711 | * - If flags is 1, the device SHOULD NOT send an interrupt. | |
712 | * - If flags is 0, the device MUST send an interrupt. | |
713 | */ | |
ca60a42c | 714 | if (vq->vring.avail->flags & VRING_AVAIL_F_NO_INTERRUPT) { |
990c91f0 | 715 | return; |
ca60a42c | 716 | } |
38bc2b8c | 717 | |
8dc425ff RR |
718 | /* |
719 | * 4.1.4.5.1: | |
720 | * | |
721 | * If MSI-X capability is disabled, the device MUST set the Queue | |
722 | * Interrupt bit in ISR status before sending a virtqueue notification | |
723 | * to the driver. | |
724 | */ | |
d9028eda | 725 | vq->dev->mmio->isr = 0x1; |
93153077 | 726 | |
38bc2b8c RR |
727 | /* Send the Guest an interrupt tell them we used something up. */ |
728 | if (write(lguest_fd, buf, sizeof(buf)) != 0) | |
d9028eda | 729 | err(1, "Triggering irq %i", vq->dev->config.irq_line); |
38bc2b8c RR |
730 | } |
731 | ||
2e04ef76 | 732 | /* |
a91d74a3 | 733 | * This looks in the virtqueue for the first available buffer, and converts |
17cbca2b RR |
734 | * it to an iovec for convenient access. Since descriptors consist of some |
735 | * number of output then some number of input descriptors, it's actually two | |
736 | * iovecs, but we pack them into one and note how many of each there were. | |
737 | * | |
a91d74a3 | 738 | * This function waits if necessary, and returns the descriptor number found. |
2e04ef76 | 739 | */ |
659a0e66 RR |
740 | static unsigned wait_for_vq_desc(struct virtqueue *vq, |
741 | struct iovec iov[], | |
742 | unsigned int *out_num, unsigned int *in_num) | |
17cbca2b | 743 | { |
d1f0132e MM |
744 | unsigned int i, head, max; |
745 | struct vring_desc *desc; | |
659a0e66 RR |
746 | u16 last_avail = lg_last_avail(vq); |
747 | ||
d39a6785 RR |
748 | /* |
749 | * 2.4.7.1: | |
750 | * | |
751 | * The driver MUST handle spurious interrupts from the device. | |
752 | * | |
753 | * That's why this is a while loop. | |
754 | */ | |
755 | ||
a91d74a3 | 756 | /* There's nothing available? */ |
659a0e66 RR |
757 | while (last_avail == vq->vring.avail->idx) { |
758 | u64 event; | |
759 | ||
a91d74a3 RR |
760 | /* |
761 | * Since we're about to sleep, now is a good time to tell the | |
762 | * Guest about what we've used up to now. | |
763 | */ | |
38bc2b8c RR |
764 | trigger_irq(vq); |
765 | ||
b60da13f RR |
766 | /* OK, now we need to know about added descriptors. */ |
767 | vq->vring.used->flags &= ~VRING_USED_F_NO_NOTIFY; | |
768 | ||
2e04ef76 RR |
769 | /* |
770 | * They could have slipped one in as we were doing that: make | |
771 | * sure it's written, then check again. | |
772 | */ | |
b60da13f RR |
773 | mb(); |
774 | if (last_avail != vq->vring.avail->idx) { | |
775 | vq->vring.used->flags |= VRING_USED_F_NO_NOTIFY; | |
776 | break; | |
777 | } | |
778 | ||
659a0e66 RR |
779 | /* Nothing new? Wait for eventfd to tell us they refilled. */ |
780 | if (read(vq->eventfd, &event, sizeof(event)) != sizeof(event)) | |
781 | errx(1, "Event read failed?"); | |
b60da13f RR |
782 | |
783 | /* We don't need to be notified again. */ | |
784 | vq->vring.used->flags |= VRING_USED_F_NO_NOTIFY; | |
659a0e66 | 785 | } |
17cbca2b RR |
786 | |
787 | /* Check it isn't doing very strange things with descriptor numbers. */ | |
b5111790 | 788 | if ((u16)(vq->vring.avail->idx - last_avail) > vq->vring.num) |
1e1c17a7 RR |
789 | bad_driver_vq(vq, "Guest moved used index from %u to %u", |
790 | last_avail, vq->vring.avail->idx); | |
17cbca2b | 791 | |
8fd9a636 RR |
792 | /* |
793 | * Make sure we read the descriptor number *after* we read the ring | |
794 | * update; don't let the cpu or compiler change the order. | |
795 | */ | |
796 | rmb(); | |
797 | ||
2e04ef76 RR |
798 | /* |
799 | * Grab the next descriptor number they're advertising, and increment | |
800 | * the index we've seen. | |
801 | */ | |
b5111790 RR |
802 | head = vq->vring.avail->ring[last_avail % vq->vring.num]; |
803 | lg_last_avail(vq)++; | |
17cbca2b RR |
804 | |
805 | /* If their number is silly, that's a fatal mistake. */ | |
806 | if (head >= vq->vring.num) | |
1e1c17a7 | 807 | bad_driver_vq(vq, "Guest says index %u is available", head); |
17cbca2b RR |
808 | |
809 | /* When we start there are none of either input nor output. */ | |
810 | *out_num = *in_num = 0; | |
811 | ||
d1f0132e MM |
812 | max = vq->vring.num; |
813 | desc = vq->vring.desc; | |
17cbca2b | 814 | i = head; |
d1f0132e | 815 | |
8fd9a636 RR |
816 | /* |
817 | * We have to read the descriptor after we read the descriptor number, | |
818 | * but there's a data dependency there so the CPU shouldn't reorder | |
819 | * that: no rmb() required. | |
820 | */ | |
821 | ||
3afe3e0f RR |
822 | do { |
823 | /* | |
824 | * If this is an indirect entry, then this buffer contains a | |
825 | * descriptor table which we handle as if it's any normal | |
826 | * descriptor chain. | |
827 | */ | |
828 | if (desc[i].flags & VRING_DESC_F_INDIRECT) { | |
d39a6785 RR |
829 | /* 2.4.5.3.1: |
830 | * | |
831 | * The driver MUST NOT set the VIRTQ_DESC_F_INDIRECT | |
832 | * flag unless the VIRTIO_F_INDIRECT_DESC feature was | |
833 | * negotiated. | |
834 | */ | |
835 | if (!(vq->dev->features_accepted & | |
836 | (1<<VIRTIO_RING_F_INDIRECT_DESC))) | |
1e1c17a7 | 837 | bad_driver_vq(vq, "vq indirect not negotiated"); |
d39a6785 RR |
838 | |
839 | /* | |
840 | * 2.4.5.3.1: | |
841 | * | |
842 | * The driver MUST NOT set the VIRTQ_DESC_F_INDIRECT | |
843 | * flag within an indirect descriptor (ie. only one | |
844 | * table per descriptor). | |
845 | */ | |
846 | if (desc != vq->vring.desc) | |
1e1c17a7 | 847 | bad_driver_vq(vq, "Indirect within indirect"); |
d39a6785 RR |
848 | |
849 | /* | |
850 | * Proposed update VIRTIO-134 spells this out: | |
851 | * | |
852 | * A driver MUST NOT set both VIRTQ_DESC_F_INDIRECT | |
853 | * and VIRTQ_DESC_F_NEXT in flags. | |
854 | */ | |
855 | if (desc[i].flags & VRING_DESC_F_NEXT) | |
1e1c17a7 | 856 | bad_driver_vq(vq, "indirect and next together"); |
d39a6785 | 857 | |
3afe3e0f | 858 | if (desc[i].len % sizeof(struct vring_desc)) |
1e1c17a7 RR |
859 | bad_driver_vq(vq, |
860 | "Invalid size for indirect table"); | |
d39a6785 RR |
861 | /* |
862 | * 2.4.5.3.2: | |
863 | * | |
864 | * The device MUST ignore the write-only flag | |
865 | * (flags&VIRTQ_DESC_F_WRITE) in the descriptor that | |
866 | * refers to an indirect table. | |
867 | * | |
868 | * We ignore it here: :) | |
869 | */ | |
d1f0132e | 870 | |
3afe3e0f | 871 | max = desc[i].len / sizeof(struct vring_desc); |
1e1c17a7 | 872 | desc = check_pointer(vq->dev, desc[i].addr, desc[i].len); |
3afe3e0f | 873 | i = 0; |
d39a6785 RR |
874 | |
875 | /* 2.4.5.3.1: | |
876 | * | |
877 | * A driver MUST NOT create a descriptor chain longer | |
878 | * than the Queue Size of the device. | |
879 | */ | |
880 | if (max > vq->pci_config.queue_size) | |
1e1c17a7 RR |
881 | bad_driver_vq(vq, |
882 | "indirect has too many entries"); | |
3afe3e0f | 883 | } |
d1f0132e | 884 | |
17cbca2b | 885 | /* Grab the first descriptor, and check it's OK. */ |
d1f0132e | 886 | iov[*out_num + *in_num].iov_len = desc[i].len; |
17cbca2b | 887 | iov[*out_num + *in_num].iov_base |
1e1c17a7 | 888 | = check_pointer(vq->dev, desc[i].addr, desc[i].len); |
17cbca2b | 889 | /* If this is an input descriptor, increment that count. */ |
d1f0132e | 890 | if (desc[i].flags & VRING_DESC_F_WRITE) |
17cbca2b RR |
891 | (*in_num)++; |
892 | else { | |
2e04ef76 RR |
893 | /* |
894 | * If it's an output descriptor, they're all supposed | |
895 | * to come before any input descriptors. | |
896 | */ | |
17cbca2b | 897 | if (*in_num) |
1e1c17a7 RR |
898 | bad_driver_vq(vq, |
899 | "Descriptor has out after in"); | |
17cbca2b RR |
900 | (*out_num)++; |
901 | } | |
902 | ||
903 | /* If we've got too many, that implies a descriptor loop. */ | |
d1f0132e | 904 | if (*out_num + *in_num > max) |
1e1c17a7 RR |
905 | bad_driver_vq(vq, "Looped descriptor"); |
906 | } while ((i = next_desc(vq->dev, desc, i, max)) != max); | |
dde79789 | 907 | |
17cbca2b | 908 | return head; |
8ca47e00 RR |
909 | } |
910 | ||
2e04ef76 | 911 | /* |
a91d74a3 RR |
912 | * After we've used one of their buffers, we tell the Guest about it. Sometime |
913 | * later we'll want to send them an interrupt using trigger_irq(); note that | |
914 | * wait_for_vq_desc() does that for us if it has to wait. | |
2e04ef76 | 915 | */ |
17cbca2b | 916 | static void add_used(struct virtqueue *vq, unsigned int head, int len) |
8ca47e00 | 917 | { |
17cbca2b RR |
918 | struct vring_used_elem *used; |
919 | ||
2e04ef76 RR |
920 | /* |
921 | * The virtqueue contains a ring of used buffers. Get a pointer to the | |
922 | * next entry in that used ring. | |
923 | */ | |
17cbca2b RR |
924 | used = &vq->vring.used->ring[vq->vring.used->idx % vq->vring.num]; |
925 | used->id = head; | |
926 | used->len = len; | |
927 | /* Make sure buffer is written before we update index. */ | |
928 | wmb(); | |
929 | vq->vring.used->idx++; | |
95c517c0 | 930 | vq->pending_used++; |
8ca47e00 RR |
931 | } |
932 | ||
17cbca2b | 933 | /* And here's the combo meal deal. Supersize me! */ |
56739c80 | 934 | static void add_used_and_trigger(struct virtqueue *vq, unsigned head, int len) |
8ca47e00 | 935 | { |
17cbca2b | 936 | add_used(vq, head, len); |
56739c80 | 937 | trigger_irq(vq); |
8ca47e00 RR |
938 | } |
939 | ||
e1e72965 RR |
940 | /* |
941 | * The Console | |
942 | * | |
2e04ef76 RR |
943 | * We associate some data with the console for our exit hack. |
944 | */ | |
1842f23c | 945 | struct console_abort { |
dde79789 | 946 | /* How many times have they hit ^C? */ |
8ca47e00 | 947 | int count; |
dde79789 | 948 | /* When did they start? */ |
8ca47e00 RR |
949 | struct timeval start; |
950 | }; | |
951 | ||
dde79789 | 952 | /* This is the routine which handles console input (ie. stdin). */ |
659a0e66 | 953 | static void console_input(struct virtqueue *vq) |
8ca47e00 | 954 | { |
8ca47e00 | 955 | int len; |
17cbca2b | 956 | unsigned int head, in_num, out_num; |
659a0e66 RR |
957 | struct console_abort *abort = vq->dev->priv; |
958 | struct iovec iov[vq->vring.num]; | |
56ae43df | 959 | |
a91d74a3 | 960 | /* Make sure there's a descriptor available. */ |
659a0e66 | 961 | head = wait_for_vq_desc(vq, iov, &out_num, &in_num); |
56ae43df | 962 | if (out_num) |
1e1c17a7 | 963 | bad_driver_vq(vq, "Output buffers in console in queue?"); |
8ca47e00 | 964 | |
a91d74a3 | 965 | /* Read into it. This is where we usually wait. */ |
659a0e66 | 966 | len = readv(STDIN_FILENO, iov, in_num); |
8ca47e00 | 967 | if (len <= 0) { |
659a0e66 | 968 | /* Ran out of input? */ |
8ca47e00 | 969 | warnx("Failed to get console input, ignoring console."); |
2e04ef76 RR |
970 | /* |
971 | * For simplicity, dying threads kill the whole Launcher. So | |
972 | * just nap here. | |
973 | */ | |
659a0e66 RR |
974 | for (;;) |
975 | pause(); | |
8ca47e00 RR |
976 | } |
977 | ||
a91d74a3 | 978 | /* Tell the Guest we used a buffer. */ |
659a0e66 | 979 | add_used_and_trigger(vq, head, len); |
8ca47e00 | 980 | |
2e04ef76 RR |
981 | /* |
982 | * Three ^C within one second? Exit. | |
dde79789 | 983 | * |
659a0e66 RR |
984 | * This is such a hack, but works surprisingly well. Each ^C has to |
985 | * be in a buffer by itself, so they can't be too fast. But we check | |
986 | * that we get three within about a second, so they can't be too | |
2e04ef76 RR |
987 | * slow. |
988 | */ | |
659a0e66 | 989 | if (len != 1 || ((char *)iov[0].iov_base)[0] != 3) { |
8ca47e00 | 990 | abort->count = 0; |
659a0e66 RR |
991 | return; |
992 | } | |
8ca47e00 | 993 | |
659a0e66 RR |
994 | abort->count++; |
995 | if (abort->count == 1) | |
996 | gettimeofday(&abort->start, NULL); | |
997 | else if (abort->count == 3) { | |
998 | struct timeval now; | |
999 | gettimeofday(&now, NULL); | |
1000 | /* Kill all Launcher processes with SIGINT, like normal ^C */ | |
1001 | if (now.tv_sec <= abort->start.tv_sec+1) | |
1002 | kill(0, SIGINT); | |
1003 | abort->count = 0; | |
1004 | } | |
8ca47e00 RR |
1005 | } |
1006 | ||
659a0e66 RR |
1007 | /* This is the routine which handles console output (ie. stdout). */ |
1008 | static void console_output(struct virtqueue *vq) | |
8ca47e00 | 1009 | { |
17cbca2b | 1010 | unsigned int head, out, in; |
17cbca2b RR |
1011 | struct iovec iov[vq->vring.num]; |
1012 | ||
a91d74a3 | 1013 | /* We usually wait in here, for the Guest to give us something. */ |
659a0e66 RR |
1014 | head = wait_for_vq_desc(vq, iov, &out, &in); |
1015 | if (in) | |
1e1c17a7 | 1016 | bad_driver_vq(vq, "Input buffers in console output queue?"); |
a91d74a3 RR |
1017 | |
1018 | /* writev can return a partial write, so we loop here. */ | |
659a0e66 RR |
1019 | while (!iov_empty(iov, out)) { |
1020 | int len = writev(STDOUT_FILENO, iov, out); | |
e0377e25 SA |
1021 | if (len <= 0) { |
1022 | warn("Write to stdout gave %i (%d)", len, errno); | |
1023 | break; | |
1024 | } | |
1e1c17a7 | 1025 | iov_consume(vq->dev, iov, out, NULL, len); |
17cbca2b | 1026 | } |
a91d74a3 RR |
1027 | |
1028 | /* | |
1029 | * We're finished with that buffer: if we're going to sleep, | |
1030 | * wait_for_vq_desc() will prod the Guest with an interrupt. | |
1031 | */ | |
38bc2b8c | 1032 | add_used(vq, head, 0); |
a161883a RR |
1033 | } |
1034 | ||
e1e72965 RR |
1035 | /* |
1036 | * The Network | |
1037 | * | |
1038 | * Handling output for network is also simple: we get all the output buffers | |
659a0e66 | 1039 | * and write them to /dev/net/tun. |
a6bd8e13 | 1040 | */ |
659a0e66 RR |
1041 | struct net_info { |
1042 | int tunfd; | |
1043 | }; | |
1044 | ||
1045 | static void net_output(struct virtqueue *vq) | |
8ca47e00 | 1046 | { |
659a0e66 RR |
1047 | struct net_info *net_info = vq->dev->priv; |
1048 | unsigned int head, out, in; | |
17cbca2b | 1049 | struct iovec iov[vq->vring.num]; |
a161883a | 1050 | |
a91d74a3 | 1051 | /* We usually wait in here for the Guest to give us a packet. */ |
659a0e66 RR |
1052 | head = wait_for_vq_desc(vq, iov, &out, &in); |
1053 | if (in) | |
1e1c17a7 | 1054 | bad_driver_vq(vq, "Input buffers in net output queue?"); |
a91d74a3 RR |
1055 | /* |
1056 | * Send the whole thing through to /dev/net/tun. It expects the exact | |
1057 | * same format: what a coincidence! | |
1058 | */ | |
659a0e66 | 1059 | if (writev(net_info->tunfd, iov, out) < 0) |
e0377e25 | 1060 | warnx("Write to tun failed (%d)?", errno); |
a91d74a3 RR |
1061 | |
1062 | /* | |
1063 | * Done with that one; wait_for_vq_desc() will send the interrupt if | |
1064 | * all packets are processed. | |
1065 | */ | |
38bc2b8c | 1066 | add_used(vq, head, 0); |
8ca47e00 RR |
1067 | } |
1068 | ||
a91d74a3 RR |
1069 | /* |
1070 | * Handling network input is a bit trickier, because I've tried to optimize it. | |
1071 | * | |
1072 | * First we have a helper routine which tells is if from this file descriptor | |
1073 | * (ie. the /dev/net/tun device) will block: | |
1074 | */ | |
4a8962e2 RR |
1075 | static bool will_block(int fd) |
1076 | { | |
1077 | fd_set fdset; | |
1078 | struct timeval zero = { 0, 0 }; | |
1079 | FD_ZERO(&fdset); | |
1080 | FD_SET(fd, &fdset); | |
1081 | return select(fd+1, &fdset, NULL, NULL, &zero) != 1; | |
1082 | } | |
1083 | ||
a91d74a3 RR |
1084 | /* |
1085 | * This handles packets coming in from the tun device to our Guest. Like all | |
1086 | * service routines, it gets called again as soon as it returns, so you don't | |
1087 | * see a while(1) loop here. | |
1088 | */ | |
659a0e66 | 1089 | static void net_input(struct virtqueue *vq) |
8ca47e00 | 1090 | { |
8ca47e00 | 1091 | int len; |
659a0e66 RR |
1092 | unsigned int head, out, in; |
1093 | struct iovec iov[vq->vring.num]; | |
1094 | struct net_info *net_info = vq->dev->priv; | |
1095 | ||
a91d74a3 RR |
1096 | /* |
1097 | * Get a descriptor to write an incoming packet into. This will also | |
1098 | * send an interrupt if they're out of descriptors. | |
1099 | */ | |
659a0e66 RR |
1100 | head = wait_for_vq_desc(vq, iov, &out, &in); |
1101 | if (out) | |
1e1c17a7 | 1102 | bad_driver_vq(vq, "Output buffers in net input queue?"); |
4a8962e2 | 1103 | |
a91d74a3 RR |
1104 | /* |
1105 | * If it looks like we'll block reading from the tun device, send them | |
1106 | * an interrupt. | |
1107 | */ | |
4a8962e2 RR |
1108 | if (vq->pending_used && will_block(net_info->tunfd)) |
1109 | trigger_irq(vq); | |
1110 | ||
a91d74a3 RR |
1111 | /* |
1112 | * Read in the packet. This is where we normally wait (when there's no | |
1113 | * incoming network traffic). | |
1114 | */ | |
659a0e66 | 1115 | len = readv(net_info->tunfd, iov, in); |
8ca47e00 | 1116 | if (len <= 0) |
e0377e25 | 1117 | warn("Failed to read from tun (%d).", errno); |
a91d74a3 RR |
1118 | |
1119 | /* | |
1120 | * Mark that packet buffer as used, but don't interrupt here. We want | |
1121 | * to wait until we've done as much work as we can. | |
1122 | */ | |
4a8962e2 | 1123 | add_used(vq, head, len); |
659a0e66 | 1124 | } |
a91d74a3 | 1125 | /*:*/ |
dde79789 | 1126 | |
a91d74a3 | 1127 | /* This is the helper to create threads: run the service routine in a loop. */ |
659a0e66 RR |
1128 | static int do_thread(void *_vq) |
1129 | { | |
1130 | struct virtqueue *vq = _vq; | |
17cbca2b | 1131 | |
659a0e66 RR |
1132 | for (;;) |
1133 | vq->service(vq); | |
1134 | return 0; | |
1135 | } | |
17cbca2b | 1136 | |
2e04ef76 RR |
1137 | /* |
1138 | * When a child dies, we kill our entire process group with SIGTERM. This | |
1139 | * also has the side effect that the shell restores the console for us! | |
1140 | */ | |
659a0e66 RR |
1141 | static void kill_launcher(int signal) |
1142 | { | |
1143 | kill(0, SIGTERM); | |
8ca47e00 RR |
1144 | } |
1145 | ||
d2dbdac3 RR |
1146 | static void reset_vq_pci_config(struct virtqueue *vq) |
1147 | { | |
1148 | vq->pci_config.queue_size = VIRTQUEUE_NUM; | |
1149 | vq->pci_config.queue_enable = 0; | |
1150 | } | |
1151 | ||
659a0e66 | 1152 | static void reset_device(struct device *dev) |
56ae43df | 1153 | { |
659a0e66 RR |
1154 | struct virtqueue *vq; |
1155 | ||
1156 | verbose("Resetting device %s\n", dev->name); | |
1157 | ||
1158 | /* Clear any features they've acked. */ | |
d9028eda | 1159 | dev->features_accepted = 0; |
659a0e66 RR |
1160 | |
1161 | /* We're going to be explicitly killing threads, so ignore them. */ | |
1162 | signal(SIGCHLD, SIG_IGN); | |
1163 | ||
d2dbdac3 RR |
1164 | /* |
1165 | * 4.1.4.3.1: | |
1166 | * | |
1167 | * The device MUST present a 0 in queue_enable on reset. | |
1168 | * | |
1169 | * This means we set it here, and reset the saved ones in every vq. | |
1170 | */ | |
1171 | dev->mmio->cfg.queue_enable = 0; | |
1172 | ||
d9028eda | 1173 | /* Get rid of the virtqueue threads */ |
659a0e66 | 1174 | for (vq = dev->vq; vq; vq = vq->next) { |
d2dbdac3 RR |
1175 | vq->last_avail_idx = 0; |
1176 | reset_vq_pci_config(vq); | |
659a0e66 RR |
1177 | if (vq->thread != (pid_t)-1) { |
1178 | kill(vq->thread, SIGTERM); | |
1179 | waitpid(vq->thread, NULL, 0); | |
1180 | vq->thread = (pid_t)-1; | |
1181 | } | |
659a0e66 RR |
1182 | } |
1183 | dev->running = false; | |
d39a6785 | 1184 | dev->wrote_features_ok = false; |
659a0e66 RR |
1185 | |
1186 | /* Now we care if threads die. */ | |
1187 | signal(SIGCHLD, (void *)kill_launcher); | |
56ae43df RR |
1188 | } |
1189 | ||
d9028eda | 1190 | static void cleanup_devices(void) |
6e5aa7ef | 1191 | { |
659a0e66 | 1192 | unsigned int i; |
659a0e66 | 1193 | |
d9028eda RR |
1194 | for (i = 1; i < MAX_PCI_DEVICES; i++) { |
1195 | struct device *d = devices.pci[i]; | |
1196 | if (!d) | |
1197 | continue; | |
1198 | reset_device(d); | |
659a0e66 | 1199 | } |
6e5aa7ef | 1200 | |
659a0e66 RR |
1201 | /* If we saved off the original terminal settings, restore them now. */ |
1202 | if (orig_term.c_lflag & (ISIG|ICANON|ECHO)) | |
1203 | tcsetattr(STDIN_FILENO, TCSANOW, &orig_term); | |
1204 | } | |
6e5aa7ef | 1205 | |
d7fbf6e9 RR |
1206 | /*L:217 |
1207 | * We do PCI. This is mainly done to let us test the kernel virtio PCI | |
1208 | * code. | |
1209 | */ | |
1210 | ||
8e709469 RR |
1211 | /* Linux expects a PCI host bridge: ours is a dummy, and first on the bus. */ |
1212 | static struct device pci_host_bridge; | |
1213 | ||
1214 | static void init_pci_host_bridge(void) | |
1215 | { | |
1216 | pci_host_bridge.name = "PCI Host Bridge"; | |
1217 | pci_host_bridge.config.class = 0x06; /* bridge */ | |
1218 | pci_host_bridge.config.subclass = 0; /* host bridge */ | |
1219 | devices.pci[0] = &pci_host_bridge; | |
1220 | } | |
1221 | ||
d7fbf6e9 RR |
1222 | /* The IO ports used to read the PCI config space. */ |
1223 | #define PCI_CONFIG_ADDR 0xCF8 | |
1224 | #define PCI_CONFIG_DATA 0xCFC | |
1225 | ||
1226 | /* | |
1227 | * Not really portable, but does help readability: this is what the Guest | |
1228 | * writes to the PCI_CONFIG_ADDR IO port. | |
1229 | */ | |
1230 | union pci_config_addr { | |
1231 | struct { | |
1232 | unsigned mbz: 2; | |
1233 | unsigned offset: 6; | |
1234 | unsigned funcnum: 3; | |
1235 | unsigned devnum: 5; | |
1236 | unsigned busnum: 8; | |
1237 | unsigned reserved: 7; | |
1238 | unsigned enabled : 1; | |
1239 | } bits; | |
1240 | u32 val; | |
1241 | }; | |
1242 | ||
1243 | /* | |
1244 | * We cache what they wrote to the address port, so we know what they're | |
1245 | * talking about when they access the data port. | |
1246 | */ | |
1247 | static union pci_config_addr pci_config_addr; | |
1248 | ||
1249 | static struct device *find_pci_device(unsigned int index) | |
1250 | { | |
1251 | return devices.pci[index]; | |
1252 | } | |
1253 | ||
1254 | /* PCI can do 1, 2 and 4 byte reads; we handle that here. */ | |
1255 | static void ioread(u16 off, u32 v, u32 mask, u32 *val) | |
1256 | { | |
1257 | assert(off < 4); | |
1258 | assert(mask == 0xFF || mask == 0xFFFF || mask == 0xFFFFFFFF); | |
1259 | *val = (v >> (off * 8)) & mask; | |
1260 | } | |
1261 | ||
1262 | /* PCI can do 1, 2 and 4 byte writes; we handle that here. */ | |
1263 | static void iowrite(u16 off, u32 v, u32 mask, u32 *dst) | |
1264 | { | |
1265 | assert(off < 4); | |
1266 | assert(mask == 0xFF || mask == 0xFFFF || mask == 0xFFFFFFFF); | |
1267 | *dst &= ~(mask << (off * 8)); | |
1268 | *dst |= (v & mask) << (off * 8); | |
1269 | } | |
1270 | ||
1271 | /* | |
1272 | * Where PCI_CONFIG_DATA accesses depends on the previous write to | |
1273 | * PCI_CONFIG_ADDR. | |
1274 | */ | |
1275 | static struct device *dev_and_reg(u32 *reg) | |
1276 | { | |
1277 | if (!pci_config_addr.bits.enabled) | |
1278 | return NULL; | |
1279 | ||
1280 | if (pci_config_addr.bits.funcnum != 0) | |
1281 | return NULL; | |
1282 | ||
1283 | if (pci_config_addr.bits.busnum != 0) | |
1284 | return NULL; | |
1285 | ||
1286 | if (pci_config_addr.bits.offset * 4 >= sizeof(struct pci_config)) | |
1287 | return NULL; | |
1288 | ||
1289 | *reg = pci_config_addr.bits.offset; | |
1290 | return find_pci_device(pci_config_addr.bits.devnum); | |
1291 | } | |
1292 | ||
59eba788 RR |
1293 | /* |
1294 | * We can get invalid combinations of values while they're writing, so we | |
1295 | * only fault if they try to write with some invalid bar/offset/length. | |
1296 | */ | |
1297 | static bool valid_bar_access(struct device *d, | |
e523caa6 | 1298 | struct virtio_pci_cfg_cap_u32 *cfg_access) |
59eba788 RR |
1299 | { |
1300 | /* We only have 1 bar (BAR0) */ | |
1301 | if (cfg_access->cap.bar != 0) | |
1302 | return false; | |
1303 | ||
1304 | /* Check it's within BAR0. */ | |
1305 | if (cfg_access->cap.offset >= d->mmio_size | |
1306 | || cfg_access->cap.offset + cfg_access->cap.length > d->mmio_size) | |
1307 | return false; | |
1308 | ||
1309 | /* Check length is 1, 2 or 4. */ | |
1310 | if (cfg_access->cap.length != 1 | |
1311 | && cfg_access->cap.length != 2 | |
1312 | && cfg_access->cap.length != 4) | |
1313 | return false; | |
1314 | ||
c97eb679 RR |
1315 | /* |
1316 | * 4.1.4.7.2: | |
1317 | * | |
1318 | * The driver MUST NOT write a cap.offset which is not a multiple of | |
1319 | * cap.length (ie. all accesses MUST be aligned). | |
1320 | */ | |
59eba788 RR |
1321 | if (cfg_access->cap.offset % cfg_access->cap.length != 0) |
1322 | return false; | |
1323 | ||
1324 | /* Return pointer into word in BAR0. */ | |
1325 | return true; | |
1326 | } | |
1327 | ||
d7fbf6e9 RR |
1328 | /* Is this accessing the PCI config address port?. */ |
1329 | static bool is_pci_addr_port(u16 port) | |
1330 | { | |
1331 | return port >= PCI_CONFIG_ADDR && port < PCI_CONFIG_ADDR + 4; | |
1332 | } | |
1333 | ||
1334 | static bool pci_addr_iowrite(u16 port, u32 mask, u32 val) | |
1335 | { | |
1336 | iowrite(port - PCI_CONFIG_ADDR, val, mask, | |
1337 | &pci_config_addr.val); | |
1338 | verbose("PCI%s: %#x/%x: bus %u dev %u func %u reg %u\n", | |
1339 | pci_config_addr.bits.enabled ? "" : " DISABLED", | |
1340 | val, mask, | |
1341 | pci_config_addr.bits.busnum, | |
1342 | pci_config_addr.bits.devnum, | |
1343 | pci_config_addr.bits.funcnum, | |
1344 | pci_config_addr.bits.offset); | |
1345 | return true; | |
1346 | } | |
1347 | ||
1348 | static void pci_addr_ioread(u16 port, u32 mask, u32 *val) | |
1349 | { | |
1350 | ioread(port - PCI_CONFIG_ADDR, pci_config_addr.val, mask, val); | |
1351 | } | |
1352 | ||
1353 | /* Is this accessing the PCI config data port?. */ | |
1354 | static bool is_pci_data_port(u16 port) | |
1355 | { | |
1356 | return port >= PCI_CONFIG_DATA && port < PCI_CONFIG_DATA + 4; | |
1357 | } | |
1358 | ||
59eba788 RR |
1359 | static void emulate_mmio_write(struct device *d, u32 off, u32 val, u32 mask); |
1360 | ||
d7fbf6e9 RR |
1361 | static bool pci_data_iowrite(u16 port, u32 mask, u32 val) |
1362 | { | |
1363 | u32 reg, portoff; | |
1364 | struct device *d = dev_and_reg(®); | |
1365 | ||
1366 | /* Complain if they don't belong to a device. */ | |
1367 | if (!d) | |
1368 | return false; | |
1369 | ||
1370 | /* They can do 1 byte writes, etc. */ | |
1371 | portoff = port - PCI_CONFIG_DATA; | |
1372 | ||
1373 | /* | |
1374 | * PCI uses a weird way to determine the BAR size: the OS | |
1375 | * writes all 1's, and sees which ones stick. | |
1376 | */ | |
1377 | if (&d->config_words[reg] == &d->config.bar[0]) { | |
1378 | int i; | |
1379 | ||
1380 | iowrite(portoff, val, mask, &d->config.bar[0]); | |
1381 | for (i = 0; (1 << i) < d->mmio_size; i++) | |
1382 | d->config.bar[0] &= ~(1 << i); | |
1383 | return true; | |
1384 | } else if ((&d->config_words[reg] > &d->config.bar[0] | |
1385 | && &d->config_words[reg] <= &d->config.bar[6]) | |
1386 | || &d->config_words[reg] == &d->config.expansion_rom_addr) { | |
1387 | /* Allow writing to any other BAR, or expansion ROM */ | |
1388 | iowrite(portoff, val, mask, &d->config_words[reg]); | |
1389 | return true; | |
1390 | /* We let them overide latency timer and cacheline size */ | |
1391 | } else if (&d->config_words[reg] == (void *)&d->config.cacheline_size) { | |
1392 | /* Only let them change the first two fields. */ | |
1393 | if (mask == 0xFFFFFFFF) | |
1394 | mask = 0xFFFF; | |
1395 | iowrite(portoff, val, mask, &d->config_words[reg]); | |
1396 | return true; | |
1397 | } else if (&d->config_words[reg] == (void *)&d->config.command | |
1398 | && mask == 0xFFFF) { | |
1399 | /* Ignore command writes. */ | |
1400 | return true; | |
59eba788 RR |
1401 | } else if (&d->config_words[reg] |
1402 | == (void *)&d->config.cfg_access.cap.bar | |
1403 | || &d->config_words[reg] | |
1404 | == &d->config.cfg_access.cap.length | |
1405 | || &d->config_words[reg] | |
1406 | == &d->config.cfg_access.cap.offset) { | |
1407 | ||
1408 | /* | |
1409 | * The VIRTIO_PCI_CAP_PCI_CFG capability | |
1410 | * provides a backdoor to access the MMIO | |
1411 | * regions without mapping them. Weird, but | |
1412 | * useful. | |
1413 | */ | |
1414 | iowrite(portoff, val, mask, &d->config_words[reg]); | |
1415 | return true; | |
b2ce1ea4 | 1416 | } else if (&d->config_words[reg] == &d->config.cfg_access.pci_cfg_data) { |
59eba788 RR |
1417 | u32 write_mask; |
1418 | ||
8dc425ff RR |
1419 | /* |
1420 | * 4.1.4.7.1: | |
1421 | * | |
1422 | * Upon detecting driver write access to pci_cfg_data, the | |
1423 | * device MUST execute a write access at offset cap.offset at | |
1424 | * BAR selected by cap.bar using the first cap.length bytes | |
1425 | * from pci_cfg_data. | |
1426 | */ | |
1427 | ||
59eba788 RR |
1428 | /* Must be bar 0 */ |
1429 | if (!valid_bar_access(d, &d->config.cfg_access)) | |
1430 | return false; | |
1431 | ||
b2ce1ea4 | 1432 | iowrite(portoff, val, mask, &d->config.cfg_access.pci_cfg_data); |
59eba788 RR |
1433 | |
1434 | /* | |
1435 | * Now emulate a write. The mask we use is set by | |
1436 | * len, *not* this write! | |
1437 | */ | |
1438 | write_mask = (1ULL<<(8*d->config.cfg_access.cap.length)) - 1; | |
1439 | verbose("Window writing %#x/%#x to bar %u, offset %u len %u\n", | |
b2ce1ea4 | 1440 | d->config.cfg_access.pci_cfg_data, write_mask, |
59eba788 RR |
1441 | d->config.cfg_access.cap.bar, |
1442 | d->config.cfg_access.cap.offset, | |
1443 | d->config.cfg_access.cap.length); | |
1444 | ||
1445 | emulate_mmio_write(d, d->config.cfg_access.cap.offset, | |
b2ce1ea4 RR |
1446 | d->config.cfg_access.pci_cfg_data, |
1447 | write_mask); | |
59eba788 | 1448 | return true; |
d7fbf6e9 RR |
1449 | } |
1450 | ||
c97eb679 RR |
1451 | /* |
1452 | * 4.1.4.1: | |
1453 | * | |
1454 | * The driver MUST NOT write into any field of the capability | |
1455 | * structure, with the exception of those with cap_type | |
1456 | * VIRTIO_PCI_CAP_PCI_CFG... | |
1457 | */ | |
d7fbf6e9 RR |
1458 | return false; |
1459 | } | |
1460 | ||
59eba788 RR |
1461 | static u32 emulate_mmio_read(struct device *d, u32 off, u32 mask); |
1462 | ||
d7fbf6e9 RR |
1463 | static void pci_data_ioread(u16 port, u32 mask, u32 *val) |
1464 | { | |
1465 | u32 reg; | |
1466 | struct device *d = dev_and_reg(®); | |
1467 | ||
1468 | if (!d) | |
1469 | return; | |
59eba788 RR |
1470 | |
1471 | /* Read through the PCI MMIO access window is special */ | |
b2ce1ea4 | 1472 | if (&d->config_words[reg] == &d->config.cfg_access.pci_cfg_data) { |
59eba788 RR |
1473 | u32 read_mask; |
1474 | ||
8dc425ff RR |
1475 | /* |
1476 | * 4.1.4.7.1: | |
1477 | * | |
1478 | * Upon detecting driver read access to pci_cfg_data, the | |
1479 | * device MUST execute a read access of length cap.length at | |
1480 | * offset cap.offset at BAR selected by cap.bar and store the | |
1481 | * first cap.length bytes in pci_cfg_data. | |
1482 | */ | |
59eba788 RR |
1483 | /* Must be bar 0 */ |
1484 | if (!valid_bar_access(d, &d->config.cfg_access)) | |
1e1c17a7 RR |
1485 | bad_driver(d, |
1486 | "Invalid cfg_access to bar%u, offset %u len %u", | |
59eba788 RR |
1487 | d->config.cfg_access.cap.bar, |
1488 | d->config.cfg_access.cap.offset, | |
1489 | d->config.cfg_access.cap.length); | |
1490 | ||
1491 | /* | |
1492 | * Read into the window. The mask we use is set by | |
1493 | * len, *not* this read! | |
1494 | */ | |
1495 | read_mask = (1ULL<<(8*d->config.cfg_access.cap.length))-1; | |
b2ce1ea4 | 1496 | d->config.cfg_access.pci_cfg_data |
59eba788 RR |
1497 | = emulate_mmio_read(d, |
1498 | d->config.cfg_access.cap.offset, | |
1499 | read_mask); | |
1500 | verbose("Window read %#x/%#x from bar %u, offset %u len %u\n", | |
b2ce1ea4 | 1501 | d->config.cfg_access.pci_cfg_data, read_mask, |
59eba788 RR |
1502 | d->config.cfg_access.cap.bar, |
1503 | d->config.cfg_access.cap.offset, | |
1504 | d->config.cfg_access.cap.length); | |
1505 | } | |
d7fbf6e9 RR |
1506 | ioread(port - PCI_CONFIG_DATA, d->config_words[reg], mask, val); |
1507 | } | |
1508 | ||
c565650b RR |
1509 | /*L:216 |
1510 | * This is where we emulate a handful of Guest instructions. It's ugly | |
1511 | * and we used to do it in the kernel but it grew over time. | |
1512 | */ | |
1513 | ||
1514 | /* | |
1515 | * We use the ptrace syscall's pt_regs struct to talk about registers | |
1516 | * to lguest: these macros convert the names to the offsets. | |
1517 | */ | |
1518 | #define getreg(name) getreg_off(offsetof(struct user_regs_struct, name)) | |
1519 | #define setreg(name, val) \ | |
1520 | setreg_off(offsetof(struct user_regs_struct, name), (val)) | |
1521 | ||
1522 | static u32 getreg_off(size_t offset) | |
1523 | { | |
1524 | u32 r; | |
1525 | unsigned long args[] = { LHREQ_GETREG, offset }; | |
1526 | ||
1527 | if (pwrite(lguest_fd, args, sizeof(args), cpu_id) < 0) | |
1528 | err(1, "Getting register %u", offset); | |
1529 | if (pread(lguest_fd, &r, sizeof(r), cpu_id) != sizeof(r)) | |
1530 | err(1, "Reading register %u", offset); | |
1531 | ||
1532 | return r; | |
1533 | } | |
1534 | ||
1535 | static void setreg_off(size_t offset, u32 val) | |
1536 | { | |
1537 | unsigned long args[] = { LHREQ_SETREG, offset, val }; | |
1538 | ||
1539 | if (pwrite(lguest_fd, args, sizeof(args), cpu_id) < 0) | |
1540 | err(1, "Setting register %u", offset); | |
1541 | } | |
1542 | ||
6a54f9ab RR |
1543 | /* Get register by instruction encoding */ |
1544 | static u32 getreg_num(unsigned regnum, u32 mask) | |
1545 | { | |
1546 | /* 8 bit ops use regnums 4-7 for high parts of word */ | |
1547 | if (mask == 0xFF && (regnum & 0x4)) | |
1548 | return getreg_num(regnum & 0x3, 0xFFFF) >> 8; | |
1549 | ||
1550 | switch (regnum) { | |
1551 | case 0: return getreg(eax) & mask; | |
1552 | case 1: return getreg(ecx) & mask; | |
1553 | case 2: return getreg(edx) & mask; | |
1554 | case 3: return getreg(ebx) & mask; | |
1555 | case 4: return getreg(esp) & mask; | |
1556 | case 5: return getreg(ebp) & mask; | |
1557 | case 6: return getreg(esi) & mask; | |
1558 | case 7: return getreg(edi) & mask; | |
1559 | } | |
1560 | abort(); | |
1561 | } | |
1562 | ||
1563 | /* Set register by instruction encoding */ | |
1564 | static void setreg_num(unsigned regnum, u32 val, u32 mask) | |
1565 | { | |
1566 | /* Don't try to set bits out of range */ | |
1567 | assert(~(val & ~mask)); | |
1568 | ||
1569 | /* 8 bit ops use regnums 4-7 for high parts of word */ | |
1570 | if (mask == 0xFF && (regnum & 0x4)) { | |
1571 | /* Construct the 16 bits we want. */ | |
1572 | val = (val << 8) | getreg_num(regnum & 0x3, 0xFF); | |
1573 | setreg_num(regnum & 0x3, val, 0xFFFF); | |
1574 | return; | |
1575 | } | |
1576 | ||
1577 | switch (regnum) { | |
1578 | case 0: setreg(eax, val | (getreg(eax) & ~mask)); return; | |
1579 | case 1: setreg(ecx, val | (getreg(ecx) & ~mask)); return; | |
1580 | case 2: setreg(edx, val | (getreg(edx) & ~mask)); return; | |
1581 | case 3: setreg(ebx, val | (getreg(ebx) & ~mask)); return; | |
1582 | case 4: setreg(esp, val | (getreg(esp) & ~mask)); return; | |
1583 | case 5: setreg(ebp, val | (getreg(ebp) & ~mask)); return; | |
1584 | case 6: setreg(esi, val | (getreg(esi) & ~mask)); return; | |
1585 | case 7: setreg(edi, val | (getreg(edi) & ~mask)); return; | |
1586 | } | |
1587 | abort(); | |
1588 | } | |
1589 | ||
1590 | /* Get bytes of displacement appended to instruction, from r/m encoding */ | |
1591 | static u32 insn_displacement_len(u8 mod_reg_rm) | |
1592 | { | |
1593 | /* Switch on the mod bits */ | |
1594 | switch (mod_reg_rm >> 6) { | |
1595 | case 0: | |
1596 | /* If mod == 0, and r/m == 101, 16-bit displacement follows */ | |
1597 | if ((mod_reg_rm & 0x7) == 0x5) | |
1598 | return 2; | |
1599 | /* Normally, mod == 0 means no literal displacement */ | |
1600 | return 0; | |
1601 | case 1: | |
1602 | /* One byte displacement */ | |
1603 | return 1; | |
1604 | case 2: | |
1605 | /* Four byte displacement */ | |
1606 | return 4; | |
1607 | case 3: | |
1608 | /* Register mode */ | |
1609 | return 0; | |
1610 | } | |
1611 | abort(); | |
1612 | } | |
1613 | ||
c565650b RR |
1614 | static void emulate_insn(const u8 insn[]) |
1615 | { | |
1616 | unsigned long args[] = { LHREQ_TRAP, 13 }; | |
1617 | unsigned int insnlen = 0, in = 0, small_operand = 0, byte_access; | |
1618 | unsigned int eax, port, mask; | |
1619 | /* | |
d7fbf6e9 | 1620 | * Default is to return all-ones on IO port reads, which traditionally |
c565650b RR |
1621 | * means "there's nothing there". |
1622 | */ | |
1623 | u32 val = 0xFFFFFFFF; | |
1624 | ||
1625 | /* | |
1626 | * This must be the Guest kernel trying to do something, not userspace! | |
1627 | * The bottom two bits of the CS segment register are the privilege | |
1628 | * level. | |
1629 | */ | |
1630 | if ((getreg(xcs) & 3) != 0x1) | |
1631 | goto no_emulate; | |
1632 | ||
1633 | /* Decoding x86 instructions is icky. */ | |
1634 | ||
1635 | /* | |
1636 | * Around 2.6.33, the kernel started using an emulation for the | |
1637 | * cmpxchg8b instruction in early boot on many configurations. This | |
1638 | * code isn't paravirtualized, and it tries to disable interrupts. | |
1639 | * Ignore it, which will Mostly Work. | |
1640 | */ | |
1641 | if (insn[insnlen] == 0xfa) { | |
1642 | /* "cli", or Clear Interrupt Enable instruction. Skip it. */ | |
1643 | insnlen = 1; | |
1644 | goto skip_insn; | |
1645 | } | |
1646 | ||
1647 | /* | |
1648 | * 0x66 is an "operand prefix". It means a 16, not 32 bit in/out. | |
1649 | */ | |
1650 | if (insn[insnlen] == 0x66) { | |
1651 | small_operand = 1; | |
1652 | /* The instruction is 1 byte so far, read the next byte. */ | |
1653 | insnlen = 1; | |
1654 | } | |
1655 | ||
1656 | /* If the lower bit isn't set, it's a single byte access */ | |
1657 | byte_access = !(insn[insnlen] & 1); | |
1658 | ||
1659 | /* | |
1660 | * Now we can ignore the lower bit and decode the 4 opcodes | |
1661 | * we need to emulate. | |
1662 | */ | |
1663 | switch (insn[insnlen] & 0xFE) { | |
1664 | case 0xE4: /* in <next byte>,%al */ | |
1665 | port = insn[insnlen+1]; | |
1666 | insnlen += 2; | |
1667 | in = 1; | |
1668 | break; | |
1669 | case 0xEC: /* in (%dx),%al */ | |
1670 | port = getreg(edx) & 0xFFFF; | |
1671 | insnlen += 1; | |
1672 | in = 1; | |
1673 | break; | |
1674 | case 0xE6: /* out %al,<next byte> */ | |
1675 | port = insn[insnlen+1]; | |
1676 | insnlen += 2; | |
1677 | break; | |
1678 | case 0xEE: /* out %al,(%dx) */ | |
1679 | port = getreg(edx) & 0xFFFF; | |
1680 | insnlen += 1; | |
1681 | break; | |
1682 | default: | |
1683 | /* OK, we don't know what this is, can't emulate. */ | |
1684 | goto no_emulate; | |
1685 | } | |
1686 | ||
1687 | /* Set a mask of the 1, 2 or 4 bytes, depending on size of IO */ | |
1688 | if (byte_access) | |
1689 | mask = 0xFF; | |
1690 | else if (small_operand) | |
1691 | mask = 0xFFFF; | |
1692 | else | |
1693 | mask = 0xFFFFFFFF; | |
1694 | ||
1695 | /* | |
1696 | * If it was an "IN" instruction, they expect the result to be read | |
1697 | * into %eax, so we change %eax. | |
1698 | */ | |
1699 | eax = getreg(eax); | |
1700 | ||
1701 | if (in) { | |
d7fbf6e9 RR |
1702 | /* This is the PS/2 keyboard status; 1 means ready for output */ |
1703 | if (port == 0x64) | |
1704 | val = 1; | |
1705 | else if (is_pci_addr_port(port)) | |
1706 | pci_addr_ioread(port, mask, &val); | |
1707 | else if (is_pci_data_port(port)) | |
1708 | pci_data_ioread(port, mask, &val); | |
1709 | ||
c565650b RR |
1710 | /* Clear the bits we're about to read */ |
1711 | eax &= ~mask; | |
1712 | /* Copy bits in from val. */ | |
1713 | eax |= val & mask; | |
1714 | /* Now update the register. */ | |
1715 | setreg(eax, eax); | |
d7fbf6e9 RR |
1716 | } else { |
1717 | if (is_pci_addr_port(port)) { | |
1718 | if (!pci_addr_iowrite(port, mask, eax)) | |
1719 | goto bad_io; | |
1720 | } else if (is_pci_data_port(port)) { | |
1721 | if (!pci_data_iowrite(port, mask, eax)) | |
1722 | goto bad_io; | |
1723 | } | |
1724 | /* There are many other ports, eg. CMOS clock, serial | |
1725 | * and parallel ports, so we ignore them all. */ | |
c565650b RR |
1726 | } |
1727 | ||
1728 | verbose("IO %s of %x to %u: %#08x\n", | |
1729 | in ? "IN" : "OUT", mask, port, eax); | |
1730 | skip_insn: | |
1731 | /* Finally, we've "done" the instruction, so move past it. */ | |
1732 | setreg(eip, getreg(eip) + insnlen); | |
1733 | return; | |
1734 | ||
d7fbf6e9 RR |
1735 | bad_io: |
1736 | warnx("Attempt to %s port %u (%#x mask)", | |
1737 | in ? "read from" : "write to", port, mask); | |
1738 | ||
c565650b RR |
1739 | no_emulate: |
1740 | /* Inject trap into Guest. */ | |
1741 | if (write(lguest_fd, args, sizeof(args)) < 0) | |
1742 | err(1, "Reinjecting trap 13 for fault at %#x", getreg(eip)); | |
1743 | } | |
1744 | ||
6a54f9ab RR |
1745 | static struct device *find_mmio_region(unsigned long paddr, u32 *off) |
1746 | { | |
1747 | unsigned int i; | |
1748 | ||
1749 | for (i = 1; i < MAX_PCI_DEVICES; i++) { | |
1750 | struct device *d = devices.pci[i]; | |
1751 | ||
1752 | if (!d) | |
1753 | continue; | |
1754 | if (paddr < d->mmio_addr) | |
1755 | continue; | |
1756 | if (paddr >= d->mmio_addr + d->mmio_size) | |
1757 | continue; | |
1758 | *off = paddr - d->mmio_addr; | |
1759 | return d; | |
1760 | } | |
1761 | return NULL; | |
1762 | } | |
1763 | ||
93153077 RR |
1764 | /* FIXME: Use vq array. */ |
1765 | static struct virtqueue *vq_by_num(struct device *d, u32 num) | |
1766 | { | |
1767 | struct virtqueue *vq = d->vq; | |
1768 | ||
1769 | while (num-- && vq) | |
1770 | vq = vq->next; | |
1771 | ||
1772 | return vq; | |
1773 | } | |
1774 | ||
1775 | static void save_vq_config(const struct virtio_pci_common_cfg *cfg, | |
1776 | struct virtqueue *vq) | |
1777 | { | |
1778 | vq->pci_config = *cfg; | |
1779 | } | |
1780 | ||
1781 | static void restore_vq_config(struct virtio_pci_common_cfg *cfg, | |
1782 | struct virtqueue *vq) | |
1783 | { | |
1784 | /* Only restore the per-vq part */ | |
1785 | size_t off = offsetof(struct virtio_pci_common_cfg, queue_size); | |
1786 | ||
1787 | memcpy((void *)cfg + off, (void *)&vq->pci_config + off, | |
1788 | sizeof(*cfg) - off); | |
1789 | } | |
1790 | ||
1791 | /* | |
d761b032 RR |
1792 | * 4.1.4.3.2: |
1793 | * | |
1794 | * The driver MUST configure the other virtqueue fields before | |
1795 | * enabling the virtqueue with queue_enable. | |
1796 | * | |
93153077 RR |
1797 | * When they enable the virtqueue, we check that their setup is valid. |
1798 | */ | |
d761b032 | 1799 | static void check_virtqueue(struct device *d, struct virtqueue *vq) |
93153077 | 1800 | { |
93153077 RR |
1801 | /* Because lguest is 32 bit, all the descriptor high bits must be 0 */ |
1802 | if (vq->pci_config.queue_desc_hi | |
1803 | || vq->pci_config.queue_avail_hi | |
1804 | || vq->pci_config.queue_used_hi) | |
1e1c17a7 | 1805 | bad_driver_vq(vq, "invalid 64-bit queue address"); |
93153077 | 1806 | |
d39a6785 RR |
1807 | /* |
1808 | * 2.4.1: | |
1809 | * | |
1810 | * The driver MUST ensure that the physical address of the first byte | |
1811 | * of each virtqueue part is a multiple of the specified alignment | |
1812 | * value in the above table. | |
1813 | */ | |
1814 | if (vq->pci_config.queue_desc_lo % 16 | |
1815 | || vq->pci_config.queue_avail_lo % 2 | |
1816 | || vq->pci_config.queue_used_lo % 4) | |
1e1c17a7 | 1817 | bad_driver_vq(vq, "invalid alignment in queue addresses"); |
d39a6785 | 1818 | |
93153077 RR |
1819 | /* Initialize the virtqueue and check they're all in range. */ |
1820 | vq->vring.num = vq->pci_config.queue_size; | |
1e1c17a7 RR |
1821 | vq->vring.desc = check_pointer(vq->dev, |
1822 | vq->pci_config.queue_desc_lo, | |
93153077 | 1823 | sizeof(*vq->vring.desc) * vq->vring.num); |
1e1c17a7 RR |
1824 | vq->vring.avail = check_pointer(vq->dev, |
1825 | vq->pci_config.queue_avail_lo, | |
93153077 RR |
1826 | sizeof(*vq->vring.avail) |
1827 | + (sizeof(vq->vring.avail->ring[0]) | |
1828 | * vq->vring.num)); | |
1e1c17a7 RR |
1829 | vq->vring.used = check_pointer(vq->dev, |
1830 | vq->pci_config.queue_used_lo, | |
93153077 RR |
1831 | sizeof(*vq->vring.used) |
1832 | + (sizeof(vq->vring.used->ring[0]) | |
1833 | * vq->vring.num)); | |
d39a6785 RR |
1834 | |
1835 | /* | |
1836 | * 2.4.9.1: | |
1837 | * | |
1838 | * The driver MUST initialize flags in the used ring to 0 | |
1839 | * when allocating the used ring. | |
1840 | */ | |
1841 | if (vq->vring.used->flags != 0) | |
1e1c17a7 RR |
1842 | bad_driver_vq(vq, "invalid initial used.flags %#x", |
1843 | vq->vring.used->flags); | |
d761b032 | 1844 | } |
93153077 | 1845 | |
d761b032 RR |
1846 | static void start_virtqueue(struct virtqueue *vq) |
1847 | { | |
1848 | /* | |
1849 | * Create stack for thread. Since the stack grows upwards, we point | |
1850 | * the stack pointer to the end of this region. | |
1851 | */ | |
1852 | char *stack = malloc(32768); | |
93153077 RR |
1853 | |
1854 | /* Create a zero-initialized eventfd. */ | |
1855 | vq->eventfd = eventfd(0, 0); | |
1856 | if (vq->eventfd < 0) | |
1857 | err(1, "Creating eventfd"); | |
1858 | ||
1859 | /* | |
1860 | * CLONE_VM: because it has to access the Guest memory, and SIGCHLD so | |
1861 | * we get a signal if it dies. | |
1862 | */ | |
1863 | vq->thread = clone(do_thread, stack + 32768, CLONE_VM | SIGCHLD, vq); | |
1864 | if (vq->thread == (pid_t)-1) | |
1865 | err(1, "Creating clone"); | |
1866 | } | |
1867 | ||
d761b032 RR |
1868 | static void start_virtqueues(struct device *d) |
1869 | { | |
1870 | struct virtqueue *vq; | |
1871 | ||
1872 | for (vq = d->vq; vq; vq = vq->next) { | |
1873 | if (vq->pci_config.queue_enable) | |
1874 | start_virtqueue(vq); | |
1875 | } | |
1876 | } | |
1877 | ||
6a54f9ab RR |
1878 | static void emulate_mmio_write(struct device *d, u32 off, u32 val, u32 mask) |
1879 | { | |
93153077 RR |
1880 | struct virtqueue *vq; |
1881 | ||
1882 | switch (off) { | |
1883 | case offsetof(struct virtio_pci_mmio, cfg.device_feature_select): | |
8dc425ff RR |
1884 | /* |
1885 | * 4.1.4.3.1: | |
1886 | * | |
1887 | * The device MUST present the feature bits it is offering in | |
1888 | * device_feature, starting at bit device_feature_select ∗ 32 | |
1889 | * for any device_feature_select written by the driver | |
1890 | */ | |
93153077 RR |
1891 | if (val == 0) |
1892 | d->mmio->cfg.device_feature = d->features; | |
1893 | else if (val == 1) | |
1894 | d->mmio->cfg.device_feature = (d->features >> 32); | |
1895 | else | |
1896 | d->mmio->cfg.device_feature = 0; | |
d39a6785 | 1897 | goto feature_write_through32; |
93153077 RR |
1898 | case offsetof(struct virtio_pci_mmio, cfg.guest_feature_select): |
1899 | if (val > 1) | |
1e1c17a7 | 1900 | bad_driver(d, "Unexpected driver select %u", val); |
d39a6785 | 1901 | goto feature_write_through32; |
93153077 RR |
1902 | case offsetof(struct virtio_pci_mmio, cfg.guest_feature): |
1903 | if (d->mmio->cfg.guest_feature_select == 0) { | |
1904 | d->features_accepted &= ~((u64)0xFFFFFFFF); | |
1905 | d->features_accepted |= val; | |
1906 | } else { | |
1907 | assert(d->mmio->cfg.guest_feature_select == 1); | |
53aceb49 | 1908 | d->features_accepted &= 0xFFFFFFFF; |
93153077 RR |
1909 | d->features_accepted |= ((u64)val) << 32; |
1910 | } | |
d39a6785 RR |
1911 | /* |
1912 | * 2.2.1: | |
1913 | * | |
1914 | * The driver MUST NOT accept a feature which the device did | |
1915 | * not offer | |
1916 | */ | |
93153077 | 1917 | if (d->features_accepted & ~d->features) |
1e1c17a7 RR |
1918 | bad_driver(d, "over-accepted features %#llx of %#llx", |
1919 | d->features_accepted, d->features); | |
d39a6785 RR |
1920 | goto feature_write_through32; |
1921 | case offsetof(struct virtio_pci_mmio, cfg.device_status): { | |
1922 | u8 prev; | |
1923 | ||
93153077 | 1924 | verbose("%s: device status -> %#x\n", d->name, val); |
8dc425ff RR |
1925 | /* |
1926 | * 4.1.4.3.1: | |
1927 | * | |
1928 | * The device MUST reset when 0 is written to device_status, | |
1929 | * and present a 0 in device_status once that is done. | |
1930 | */ | |
d39a6785 | 1931 | if (val == 0) { |
d9028eda | 1932 | reset_device(d); |
d39a6785 RR |
1933 | goto write_through8; |
1934 | } | |
1935 | ||
1936 | /* 2.1.1: The driver MUST NOT clear a device status bit. */ | |
1937 | if (d->mmio->cfg.device_status & ~val) | |
1e1c17a7 RR |
1938 | bad_driver(d, "unset of device status bit %#x -> %#x", |
1939 | d->mmio->cfg.device_status, val); | |
d761b032 RR |
1940 | |
1941 | /* | |
1942 | * 2.1.2: | |
1943 | * | |
1944 | * The device MUST NOT consume buffers or notify the driver | |
1945 | * before DRIVER_OK. | |
1946 | */ | |
1947 | if (val & VIRTIO_CONFIG_S_DRIVER_OK | |
1948 | && !(d->mmio->cfg.device_status & VIRTIO_CONFIG_S_DRIVER_OK)) | |
1949 | start_virtqueues(d); | |
1950 | ||
d39a6785 RR |
1951 | /* |
1952 | * 3.1.1: | |
1953 | * | |
1954 | * The driver MUST follow this sequence to initialize a device: | |
1955 | * - Reset the device. | |
1956 | * - Set the ACKNOWLEDGE status bit: the guest OS has | |
1957 | * notice the device. | |
1958 | * - Set the DRIVER status bit: the guest OS knows how | |
1959 | * to drive the device. | |
1960 | * - Read device feature bits, and write the subset | |
1961 | * of feature bits understood by the OS and driver | |
1962 | * to the device. During this step the driver MAY | |
1963 | * read (but MUST NOT write) the device-specific | |
1964 | * configuration fields to check that it can | |
1965 | * support the device before accepting it. | |
1966 | * - Set the FEATURES_OK status bit. The driver | |
1967 | * MUST not accept new feature bits after this | |
1968 | * step. | |
1969 | * - Re-read device status to ensure the FEATURES_OK | |
1970 | * bit is still set: otherwise, the device does | |
1971 | * not support our subset of features and the | |
1972 | * device is unusable. | |
1973 | * - Perform device-specific setup, including | |
1974 | * discovery of virtqueues for the device, | |
1975 | * optional per-bus setup, reading and possibly | |
1976 | * writing the device’s virtio configuration | |
1977 | * space, and population of virtqueues. | |
1978 | * - Set the DRIVER_OK status bit. At this point the | |
1979 | * device is “live”. | |
1980 | */ | |
1981 | prev = 0; | |
1982 | switch (val & ~d->mmio->cfg.device_status) { | |
1983 | case VIRTIO_CONFIG_S_DRIVER_OK: | |
1984 | prev |= VIRTIO_CONFIG_S_FEATURES_OK; /* fall thru */ | |
1985 | case VIRTIO_CONFIG_S_FEATURES_OK: | |
1986 | prev |= VIRTIO_CONFIG_S_DRIVER; /* fall thru */ | |
1987 | case VIRTIO_CONFIG_S_DRIVER: | |
1988 | prev |= VIRTIO_CONFIG_S_ACKNOWLEDGE; /* fall thru */ | |
1989 | case VIRTIO_CONFIG_S_ACKNOWLEDGE: | |
1990 | break; | |
1991 | default: | |
1e1c17a7 RR |
1992 | bad_driver(d, "unknown device status bit %#x -> %#x", |
1993 | d->mmio->cfg.device_status, val); | |
d39a6785 RR |
1994 | } |
1995 | if (d->mmio->cfg.device_status != prev) | |
1e1c17a7 RR |
1996 | bad_driver(d, "unexpected status transition %#x -> %#x", |
1997 | d->mmio->cfg.device_status, val); | |
d39a6785 RR |
1998 | |
1999 | /* If they just wrote FEATURES_OK, we make sure they read */ | |
2000 | switch (val & ~d->mmio->cfg.device_status) { | |
2001 | case VIRTIO_CONFIG_S_FEATURES_OK: | |
2002 | d->wrote_features_ok = true; | |
2003 | break; | |
2004 | case VIRTIO_CONFIG_S_DRIVER_OK: | |
2005 | if (d->wrote_features_ok) | |
1e1c17a7 | 2006 | bad_driver(d, "did not re-read FEATURES_OK"); |
d39a6785 RR |
2007 | break; |
2008 | } | |
93153077 | 2009 | goto write_through8; |
d39a6785 | 2010 | } |
93153077 RR |
2011 | case offsetof(struct virtio_pci_mmio, cfg.queue_select): |
2012 | vq = vq_by_num(d, val); | |
8dc425ff RR |
2013 | /* |
2014 | * 4.1.4.3.1: | |
2015 | * | |
2016 | * The device MUST present a 0 in queue_size if the virtqueue | |
2017 | * corresponding to the current queue_select is unavailable. | |
2018 | */ | |
93153077 RR |
2019 | if (!vq) { |
2020 | d->mmio->cfg.queue_size = 0; | |
2021 | goto write_through16; | |
2022 | } | |
2023 | /* Save registers for old vq, if it was a valid vq */ | |
2024 | if (d->mmio->cfg.queue_size) | |
2025 | save_vq_config(&d->mmio->cfg, | |
2026 | vq_by_num(d, d->mmio->cfg.queue_select)); | |
2027 | /* Restore the registers for the queue they asked for */ | |
2028 | restore_vq_config(&d->mmio->cfg, vq); | |
2029 | goto write_through16; | |
2030 | case offsetof(struct virtio_pci_mmio, cfg.queue_size): | |
c97eb679 RR |
2031 | /* |
2032 | * 4.1.4.3.2: | |
2033 | * | |
2034 | * The driver MUST NOT write a value which is not a power of 2 | |
2035 | * to queue_size. | |
2036 | */ | |
93153077 | 2037 | if (val & (val-1)) |
1e1c17a7 | 2038 | bad_driver(d, "invalid queue size %u", val); |
93153077 | 2039 | if (d->mmio->cfg.queue_enable) |
1e1c17a7 | 2040 | bad_driver(d, "changing queue size on live device"); |
93153077 RR |
2041 | goto write_through16; |
2042 | case offsetof(struct virtio_pci_mmio, cfg.queue_msix_vector): | |
1e1c17a7 | 2043 | bad_driver(d, "attempt to set MSIX vector to %u", val); |
d39a6785 RR |
2044 | case offsetof(struct virtio_pci_mmio, cfg.queue_enable): { |
2045 | struct virtqueue *vq = vq_by_num(d, d->mmio->cfg.queue_select); | |
2046 | ||
c97eb679 RR |
2047 | /* |
2048 | * 4.1.4.3.2: | |
2049 | * | |
2050 | * The driver MUST NOT write a 0 to queue_enable. | |
2051 | */ | |
93153077 | 2052 | if (val != 1) |
1e1c17a7 | 2053 | bad_driver(d, "setting queue_enable to %u", val); |
d39a6785 | 2054 | |
c97eb679 | 2055 | /* |
d39a6785 | 2056 | * 3.1.1: |
c97eb679 | 2057 | * |
d39a6785 RR |
2058 | * 7. Perform device-specific setup, including discovery of |
2059 | * virtqueues for the device, optional per-bus setup, | |
2060 | * reading and possibly writing the device’s virtio | |
2061 | * configuration space, and population of virtqueues. | |
2062 | * 8. Set the DRIVER_OK status bit. | |
2063 | * | |
2064 | * All our devices require all virtqueues to be enabled, so | |
2065 | * they should have done that before setting DRIVER_OK. | |
c97eb679 | 2066 | */ |
d39a6785 | 2067 | if (d->mmio->cfg.device_status & VIRTIO_CONFIG_S_DRIVER_OK) |
1e1c17a7 | 2068 | bad_driver(d, "enabling vq after DRIVER_OK"); |
d39a6785 RR |
2069 | |
2070 | d->mmio->cfg.queue_enable = val; | |
2071 | save_vq_config(&d->mmio->cfg, vq); | |
2072 | check_virtqueue(d, vq); | |
93153077 | 2073 | goto write_through16; |
d39a6785 | 2074 | } |
93153077 | 2075 | case offsetof(struct virtio_pci_mmio, cfg.queue_notify_off): |
1e1c17a7 | 2076 | bad_driver(d, "attempt to write to queue_notify_off"); |
93153077 RR |
2077 | case offsetof(struct virtio_pci_mmio, cfg.queue_desc_lo): |
2078 | case offsetof(struct virtio_pci_mmio, cfg.queue_desc_hi): | |
2079 | case offsetof(struct virtio_pci_mmio, cfg.queue_avail_lo): | |
2080 | case offsetof(struct virtio_pci_mmio, cfg.queue_avail_hi): | |
2081 | case offsetof(struct virtio_pci_mmio, cfg.queue_used_lo): | |
2082 | case offsetof(struct virtio_pci_mmio, cfg.queue_used_hi): | |
c97eb679 RR |
2083 | /* |
2084 | * 4.1.4.3.2: | |
2085 | * | |
2086 | * The driver MUST configure the other virtqueue fields before | |
2087 | * enabling the virtqueue with queue_enable. | |
2088 | */ | |
93153077 | 2089 | if (d->mmio->cfg.queue_enable) |
1e1c17a7 | 2090 | bad_driver(d, "changing queue on live device"); |
d39a6785 RR |
2091 | |
2092 | /* | |
2093 | * 3.1.1: | |
2094 | * | |
2095 | * The driver MUST follow this sequence to initialize a device: | |
2096 | *... | |
2097 | * 5. Set the FEATURES_OK status bit. The driver MUST not | |
2098 | * accept new feature bits after this step. | |
2099 | */ | |
2100 | if (!(d->mmio->cfg.device_status & VIRTIO_CONFIG_S_FEATURES_OK)) | |
1e1c17a7 | 2101 | bad_driver(d, "setting up vq before FEATURES_OK"); |
d39a6785 RR |
2102 | |
2103 | /* | |
2104 | * 6. Re-read device status to ensure the FEATURES_OK bit is | |
2105 | * still set... | |
2106 | */ | |
2107 | if (d->wrote_features_ok) | |
1e1c17a7 | 2108 | bad_driver(d, "didn't re-read FEATURES_OK before setup"); |
d39a6785 | 2109 | |
93153077 RR |
2110 | goto write_through32; |
2111 | case offsetof(struct virtio_pci_mmio, notify): | |
2112 | vq = vq_by_num(d, val); | |
2113 | if (!vq) | |
1e1c17a7 | 2114 | bad_driver(d, "Invalid vq notification on %u", val); |
93153077 RR |
2115 | /* Notify the process handling this vq by adding 1 to eventfd */ |
2116 | write(vq->eventfd, "\1\0\0\0\0\0\0\0", 8); | |
2117 | goto write_through16; | |
2118 | case offsetof(struct virtio_pci_mmio, isr): | |
1e1c17a7 | 2119 | bad_driver(d, "Unexpected write to isr"); |
e8330d9b RR |
2120 | /* Weird corner case: write to emerg_wr of console */ |
2121 | case sizeof(struct virtio_pci_mmio) | |
2122 | + offsetof(struct virtio_console_config, emerg_wr): | |
2123 | if (strcmp(d->name, "console") == 0) { | |
2124 | char c = val; | |
2125 | write(STDOUT_FILENO, &c, 1); | |
2126 | goto write_through32; | |
2127 | } | |
2128 | /* Fall through... */ | |
93153077 | 2129 | default: |
c97eb679 RR |
2130 | /* |
2131 | * 4.1.4.3.2: | |
2132 | * | |
2133 | * The driver MUST NOT write to device_feature, num_queues, | |
2134 | * config_generation or queue_notify_off. | |
2135 | */ | |
1e1c17a7 | 2136 | bad_driver(d, "Unexpected write to offset %u", off); |
93153077 RR |
2137 | } |
2138 | ||
d39a6785 RR |
2139 | feature_write_through32: |
2140 | /* | |
2141 | * 3.1.1: | |
2142 | * | |
2143 | * The driver MUST follow this sequence to initialize a device: | |
2144 | *... | |
2145 | * - Set the DRIVER status bit: the guest OS knows how | |
2146 | * to drive the device. | |
2147 | * - Read device feature bits, and write the subset | |
2148 | * of feature bits understood by the OS and driver | |
2149 | * to the device. | |
2150 | *... | |
2151 | * - Set the FEATURES_OK status bit. The driver MUST not | |
2152 | * accept new feature bits after this step. | |
2153 | */ | |
2154 | if (!(d->mmio->cfg.device_status & VIRTIO_CONFIG_S_DRIVER)) | |
1e1c17a7 | 2155 | bad_driver(d, "feature write before VIRTIO_CONFIG_S_DRIVER"); |
d39a6785 | 2156 | if (d->mmio->cfg.device_status & VIRTIO_CONFIG_S_FEATURES_OK) |
1e1c17a7 | 2157 | bad_driver(d, "feature write after VIRTIO_CONFIG_S_FEATURES_OK"); |
c97eb679 RR |
2158 | |
2159 | /* | |
2160 | * 4.1.3.1: | |
2161 | * | |
2162 | * The driver MUST access each field using the “natural” access | |
2163 | * method, i.e. 32-bit accesses for 32-bit fields, 16-bit accesses for | |
2164 | * 16-bit fields and 8-bit accesses for 8-bit fields. | |
2165 | */ | |
93153077 RR |
2166 | write_through32: |
2167 | if (mask != 0xFFFFFFFF) { | |
1e1c17a7 RR |
2168 | bad_driver(d, "non-32-bit write to offset %u (%#x)", |
2169 | off, getreg(eip)); | |
93153077 RR |
2170 | return; |
2171 | } | |
2172 | memcpy((char *)d->mmio + off, &val, 4); | |
2173 | return; | |
2174 | ||
2175 | write_through16: | |
2176 | if (mask != 0xFFFF) | |
1e1c17a7 RR |
2177 | bad_driver(d, "non-16-bit write to offset %u (%#x)", |
2178 | off, getreg(eip)); | |
93153077 RR |
2179 | memcpy((char *)d->mmio + off, &val, 2); |
2180 | return; | |
2181 | ||
2182 | write_through8: | |
2183 | if (mask != 0xFF) | |
1e1c17a7 RR |
2184 | bad_driver(d, "non-8-bit write to offset %u (%#x)", |
2185 | off, getreg(eip)); | |
93153077 RR |
2186 | memcpy((char *)d->mmio + off, &val, 1); |
2187 | return; | |
6a54f9ab RR |
2188 | } |
2189 | ||
2190 | static u32 emulate_mmio_read(struct device *d, u32 off, u32 mask) | |
2191 | { | |
93153077 RR |
2192 | u8 isr; |
2193 | u32 val = 0; | |
2194 | ||
2195 | switch (off) { | |
2196 | case offsetof(struct virtio_pci_mmio, cfg.device_feature_select): | |
2197 | case offsetof(struct virtio_pci_mmio, cfg.device_feature): | |
2198 | case offsetof(struct virtio_pci_mmio, cfg.guest_feature_select): | |
2199 | case offsetof(struct virtio_pci_mmio, cfg.guest_feature): | |
d39a6785 RR |
2200 | /* |
2201 | * 3.1.1: | |
2202 | * | |
2203 | * The driver MUST follow this sequence to initialize a device: | |
2204 | *... | |
2205 | * - Set the DRIVER status bit: the guest OS knows how | |
2206 | * to drive the device. | |
2207 | * - Read device feature bits, and write the subset | |
2208 | * of feature bits understood by the OS and driver | |
2209 | * to the device. | |
2210 | */ | |
2211 | if (!(d->mmio->cfg.device_status & VIRTIO_CONFIG_S_DRIVER)) | |
1e1c17a7 RR |
2212 | bad_driver(d, |
2213 | "feature read before VIRTIO_CONFIG_S_DRIVER"); | |
93153077 RR |
2214 | goto read_through32; |
2215 | case offsetof(struct virtio_pci_mmio, cfg.msix_config): | |
1e1c17a7 | 2216 | bad_driver(d, "read of msix_config"); |
93153077 RR |
2217 | case offsetof(struct virtio_pci_mmio, cfg.num_queues): |
2218 | goto read_through16; | |
2219 | case offsetof(struct virtio_pci_mmio, cfg.device_status): | |
d39a6785 RR |
2220 | /* As they did read, any write of FEATURES_OK is now fine. */ |
2221 | d->wrote_features_ok = false; | |
2222 | goto read_through8; | |
93153077 | 2223 | case offsetof(struct virtio_pci_mmio, cfg.config_generation): |
8dc425ff RR |
2224 | /* |
2225 | * 4.1.4.3.1: | |
2226 | * | |
2227 | * The device MUST present a changed config_generation after | |
2228 | * the driver has read a device-specific configuration value | |
2229 | * which has changed since any part of the device-specific | |
2230 | * configuration was last read. | |
2231 | * | |
2232 | * This is simple: none of our devices change config, so this | |
2233 | * is always 0. | |
2234 | */ | |
93153077 RR |
2235 | goto read_through8; |
2236 | case offsetof(struct virtio_pci_mmio, notify): | |
d39a6785 RR |
2237 | /* |
2238 | * 3.1.1: | |
2239 | * | |
2240 | * The driver MUST NOT notify the device before setting | |
2241 | * DRIVER_OK. | |
2242 | */ | |
2243 | if (!(d->mmio->cfg.device_status & VIRTIO_CONFIG_S_DRIVER_OK)) | |
1e1c17a7 | 2244 | bad_driver(d, "notify before VIRTIO_CONFIG_S_DRIVER_OK"); |
93153077 RR |
2245 | goto read_through16; |
2246 | case offsetof(struct virtio_pci_mmio, isr): | |
2247 | if (mask != 0xFF) | |
1e1c17a7 RR |
2248 | bad_driver(d, "non-8-bit read from offset %u (%#x)", |
2249 | off, getreg(eip)); | |
93153077 | 2250 | isr = d->mmio->isr; |
8dc425ff RR |
2251 | /* |
2252 | * 4.1.4.5.1: | |
2253 | * | |
2254 | * The device MUST reset ISR status to 0 on driver read. | |
2255 | */ | |
93153077 RR |
2256 | d->mmio->isr = 0; |
2257 | return isr; | |
2258 | case offsetof(struct virtio_pci_mmio, padding): | |
1e1c17a7 | 2259 | bad_driver(d, "read from padding (%#x)", getreg(eip)); |
93153077 RR |
2260 | default: |
2261 | /* Read from device config space, beware unaligned overflow */ | |
2262 | if (off > d->mmio_size - 4) | |
1e1c17a7 | 2263 | bad_driver(d, "read past end (%#x)", getreg(eip)); |
d39a6785 RR |
2264 | |
2265 | /* | |
2266 | * 3.1.1: | |
2267 | * The driver MUST follow this sequence to initialize a device: | |
2268 | *... | |
2269 | * 3. Set the DRIVER status bit: the guest OS knows how to | |
2270 | * drive the device. | |
2271 | * 4. Read device feature bits, and write the subset of | |
2272 | * feature bits understood by the OS and driver to the | |
2273 | * device. During this step the driver MAY read (but MUST NOT | |
2274 | * write) the device-specific configuration fields to check | |
2275 | * that it can support the device before accepting it. | |
2276 | */ | |
2277 | if (!(d->mmio->cfg.device_status & VIRTIO_CONFIG_S_DRIVER)) | |
1e1c17a7 RR |
2278 | bad_driver(d, |
2279 | "config read before VIRTIO_CONFIG_S_DRIVER"); | |
d39a6785 | 2280 | |
93153077 RR |
2281 | if (mask == 0xFFFFFFFF) |
2282 | goto read_through32; | |
2283 | else if (mask == 0xFFFF) | |
2284 | goto read_through16; | |
2285 | else | |
2286 | goto read_through8; | |
2287 | } | |
2288 | ||
c97eb679 RR |
2289 | /* |
2290 | * 4.1.3.1: | |
2291 | * | |
2292 | * The driver MUST access each field using the “natural” access | |
2293 | * method, i.e. 32-bit accesses for 32-bit fields, 16-bit accesses for | |
2294 | * 16-bit fields and 8-bit accesses for 8-bit fields. | |
2295 | */ | |
93153077 RR |
2296 | read_through32: |
2297 | if (mask != 0xFFFFFFFF) | |
1e1c17a7 RR |
2298 | bad_driver(d, "non-32-bit read to offset %u (%#x)", |
2299 | off, getreg(eip)); | |
93153077 RR |
2300 | memcpy(&val, (char *)d->mmio + off, 4); |
2301 | return val; | |
2302 | ||
2303 | read_through16: | |
2304 | if (mask != 0xFFFF) | |
1e1c17a7 RR |
2305 | bad_driver(d, "non-16-bit read to offset %u (%#x)", |
2306 | off, getreg(eip)); | |
93153077 RR |
2307 | memcpy(&val, (char *)d->mmio + off, 2); |
2308 | return val; | |
2309 | ||
2310 | read_through8: | |
2311 | if (mask != 0xFF) | |
1e1c17a7 RR |
2312 | bad_driver(d, "non-8-bit read to offset %u (%#x)", |
2313 | off, getreg(eip)); | |
93153077 RR |
2314 | memcpy(&val, (char *)d->mmio + off, 1); |
2315 | return val; | |
6a54f9ab RR |
2316 | } |
2317 | ||
2318 | static void emulate_mmio(unsigned long paddr, const u8 *insn) | |
2319 | { | |
2320 | u32 val, off, mask = 0xFFFFFFFF, insnlen = 0; | |
2321 | struct device *d = find_mmio_region(paddr, &off); | |
2322 | unsigned long args[] = { LHREQ_TRAP, 14 }; | |
2323 | ||
2324 | if (!d) { | |
2325 | warnx("MMIO touching %#08lx (not a device)", paddr); | |
2326 | goto reinject; | |
2327 | } | |
2328 | ||
2329 | /* Prefix makes it a 16 bit op */ | |
2330 | if (insn[0] == 0x66) { | |
2331 | mask = 0xFFFF; | |
2332 | insnlen++; | |
2333 | } | |
2334 | ||
2335 | /* iowrite */ | |
2336 | if (insn[insnlen] == 0x89) { | |
2337 | /* Next byte is r/m byte: bits 3-5 are register. */ | |
2338 | val = getreg_num((insn[insnlen+1] >> 3) & 0x7, mask); | |
2339 | emulate_mmio_write(d, off, val, mask); | |
2340 | insnlen += 2 + insn_displacement_len(insn[insnlen+1]); | |
2341 | } else if (insn[insnlen] == 0x8b) { /* ioread */ | |
2342 | /* Next byte is r/m byte: bits 3-5 are register. */ | |
2343 | val = emulate_mmio_read(d, off, mask); | |
2344 | setreg_num((insn[insnlen+1] >> 3) & 0x7, val, mask); | |
2345 | insnlen += 2 + insn_displacement_len(insn[insnlen+1]); | |
2346 | } else if (insn[0] == 0x88) { /* 8-bit iowrite */ | |
2347 | mask = 0xff; | |
2348 | /* Next byte is r/m byte: bits 3-5 are register. */ | |
2349 | val = getreg_num((insn[1] >> 3) & 0x7, mask); | |
2350 | emulate_mmio_write(d, off, val, mask); | |
2351 | insnlen = 2 + insn_displacement_len(insn[1]); | |
2352 | } else if (insn[0] == 0x8a) { /* 8-bit ioread */ | |
2353 | mask = 0xff; | |
2354 | val = emulate_mmio_read(d, off, mask); | |
2355 | setreg_num((insn[1] >> 3) & 0x7, val, mask); | |
2356 | insnlen = 2 + insn_displacement_len(insn[1]); | |
2357 | } else { | |
2358 | warnx("Unknown MMIO instruction touching %#08lx:" | |
2359 | " %02x %02x %02x %02x at %u", | |
2360 | paddr, insn[0], insn[1], insn[2], insn[3], getreg(eip)); | |
2361 | reinject: | |
2362 | /* Inject trap into Guest. */ | |
2363 | if (write(lguest_fd, args, sizeof(args)) < 0) | |
2364 | err(1, "Reinjecting trap 14 for fault at %#x", | |
2365 | getreg(eip)); | |
2366 | return; | |
2367 | } | |
2368 | ||
2369 | /* Finally, we've "done" the instruction, so move past it. */ | |
2370 | setreg(eip, getreg(eip) + insnlen); | |
2371 | } | |
c565650b | 2372 | |
dde79789 RR |
2373 | /*L:190 |
2374 | * Device Setup | |
2375 | * | |
2376 | * All devices need a descriptor so the Guest knows it exists, and a "struct | |
2377 | * device" so the Launcher can keep track of it. We have common helper | |
a6bd8e13 RR |
2378 | * routines to allocate and manage them. |
2379 | */ | |
93153077 | 2380 | static void add_pci_virtqueue(struct device *dev, |
17c56d6d RR |
2381 | void (*service)(struct virtqueue *), |
2382 | const char *name) | |
93153077 RR |
2383 | { |
2384 | struct virtqueue **i, *vq = malloc(sizeof(*vq)); | |
2385 | ||
2386 | /* Initialize the virtqueue */ | |
2387 | vq->next = NULL; | |
2388 | vq->last_avail_idx = 0; | |
2389 | vq->dev = dev; | |
17c56d6d | 2390 | vq->name = name; |
93153077 RR |
2391 | |
2392 | /* | |
2393 | * This is the routine the service thread will run, and its Process ID | |
2394 | * once it's running. | |
2395 | */ | |
2396 | vq->service = service; | |
2397 | vq->thread = (pid_t)-1; | |
2398 | ||
2399 | /* Initialize the configuration. */ | |
d2dbdac3 | 2400 | reset_vq_pci_config(vq); |
93153077 RR |
2401 | vq->pci_config.queue_notify_off = 0; |
2402 | ||
2403 | /* Add one to the number of queues */ | |
2404 | vq->dev->mmio->cfg.num_queues++; | |
2405 | ||
93153077 RR |
2406 | /* |
2407 | * Add to tail of list, so dev->vq is first vq, dev->vq->next is | |
2408 | * second. | |
2409 | */ | |
2410 | for (i = &dev->vq; *i; i = &(*i)->next); | |
2411 | *i = vq; | |
2412 | } | |
2413 | ||
d9028eda | 2414 | /* The Guest accesses the feature bits via the PCI common config MMIO region */ |
93153077 RR |
2415 | static void add_pci_feature(struct device *dev, unsigned bit) |
2416 | { | |
2417 | dev->features |= (1ULL << bit); | |
2418 | } | |
2419 | ||
93153077 RR |
2420 | /* For devices with no config. */ |
2421 | static void no_device_config(struct device *dev) | |
2422 | { | |
2423 | dev->mmio_addr = get_mmio_region(dev->mmio_size); | |
2424 | ||
2425 | dev->config.bar[0] = dev->mmio_addr; | |
2426 | /* Bottom 4 bits must be zero */ | |
2427 | assert(~(dev->config.bar[0] & 0xF)); | |
2428 | } | |
2429 | ||
2430 | /* This puts the device config into BAR0 */ | |
2431 | static void set_device_config(struct device *dev, const void *conf, size_t len) | |
2432 | { | |
2433 | /* Set up BAR 0 */ | |
2434 | dev->mmio_size += len; | |
2435 | dev->mmio = realloc(dev->mmio, dev->mmio_size); | |
2436 | memcpy(dev->mmio + 1, conf, len); | |
2437 | ||
8dc425ff RR |
2438 | /* |
2439 | * 4.1.4.6: | |
2440 | * | |
2441 | * The device MUST present at least one VIRTIO_PCI_CAP_DEVICE_CFG | |
2442 | * capability for any device type which has a device-specific | |
2443 | * configuration. | |
2444 | */ | |
93153077 RR |
2445 | /* Hook up device cfg */ |
2446 | dev->config.cfg_access.cap.cap_next | |
2447 | = offsetof(struct pci_config, device); | |
2448 | ||
8dc425ff RR |
2449 | /* |
2450 | * 4.1.4.6.1: | |
2451 | * | |
2452 | * The offset for the device-specific configuration MUST be 4-byte | |
2453 | * aligned. | |
2454 | */ | |
2455 | assert(dev->config.cfg_access.cap.cap_next % 4 == 0); | |
2456 | ||
93153077 RR |
2457 | /* Fix up device cfg field length. */ |
2458 | dev->config.device.length = len; | |
2459 | ||
2460 | /* The rest is the same as the no-config case */ | |
2461 | no_device_config(dev); | |
2462 | } | |
2463 | ||
2464 | static void init_cap(struct virtio_pci_cap *cap, size_t caplen, int type, | |
2465 | size_t bar_offset, size_t bar_bytes, u8 next) | |
2466 | { | |
2467 | cap->cap_vndr = PCI_CAP_ID_VNDR; | |
2468 | cap->cap_next = next; | |
2469 | cap->cap_len = caplen; | |
2470 | cap->cfg_type = type; | |
2471 | cap->bar = 0; | |
2472 | memset(cap->padding, 0, sizeof(cap->padding)); | |
2473 | cap->offset = bar_offset; | |
2474 | cap->length = bar_bytes; | |
2475 | } | |
2476 | ||
2477 | /* | |
2478 | * This sets up the pci_config structure, as defined in the virtio 1.0 | |
2479 | * standard (and PCI standard). | |
2480 | */ | |
2481 | static void init_pci_config(struct pci_config *pci, u16 type, | |
2482 | u8 class, u8 subclass) | |
2483 | { | |
2484 | size_t bar_offset, bar_len; | |
2485 | ||
8dc425ff RR |
2486 | /* |
2487 | * 4.1.4.4.1: | |
2488 | * | |
2489 | * The device MUST either present notify_off_multiplier as an even | |
2490 | * power of 2, or present notify_off_multiplier as 0. | |
d39a6785 RR |
2491 | * |
2492 | * 2.1.2: | |
2493 | * | |
2494 | * The device MUST initialize device status to 0 upon reset. | |
8dc425ff | 2495 | */ |
93153077 RR |
2496 | memset(pci, 0, sizeof(*pci)); |
2497 | ||
2498 | /* 4.1.2.1: Devices MUST have the PCI Vendor ID 0x1AF4 */ | |
2499 | pci->vendor_id = 0x1AF4; | |
2500 | /* 4.1.2.1: ... PCI Device ID calculated by adding 0x1040 ... */ | |
2501 | pci->device_id = 0x1040 + type; | |
2502 | ||
2503 | /* | |
2504 | * PCI have specific codes for different types of devices. | |
2505 | * Linux doesn't care, but it's a good clue for people looking | |
2506 | * at the device. | |
93153077 RR |
2507 | */ |
2508 | pci->class = class; | |
2509 | pci->subclass = subclass; | |
2510 | ||
2511 | /* | |
8dc425ff RR |
2512 | * 4.1.2.1: |
2513 | * | |
2514 | * Non-transitional devices SHOULD have a PCI Revision ID of 1 or | |
2515 | * higher | |
93153077 RR |
2516 | */ |
2517 | pci->revid = 1; | |
2518 | ||
2519 | /* | |
8dc425ff RR |
2520 | * 4.1.2.1: |
2521 | * | |
2522 | * Non-transitional devices SHOULD have a PCI Subsystem Device ID of | |
2523 | * 0x40 or higher. | |
93153077 RR |
2524 | */ |
2525 | pci->subsystem_device_id = 0x40; | |
2526 | ||
2527 | /* We use our dummy interrupt controller, and irq_line is the irq */ | |
2528 | pci->irq_line = devices.next_irq++; | |
2529 | pci->irq_pin = 0; | |
2530 | ||
2531 | /* Support for extended capabilities. */ | |
2532 | pci->status = (1 << 4); | |
2533 | ||
2534 | /* Link them in. */ | |
8dc425ff RR |
2535 | /* |
2536 | * 4.1.4.3.1: | |
2537 | * | |
2538 | * The device MUST present at least one common configuration | |
2539 | * capability. | |
2540 | */ | |
93153077 RR |
2541 | pci->capabilities = offsetof(struct pci_config, common); |
2542 | ||
8dc425ff RR |
2543 | /* 4.1.4.3.1 ... offset MUST be 4-byte aligned. */ |
2544 | assert(pci->capabilities % 4 == 0); | |
2545 | ||
93153077 RR |
2546 | bar_offset = offsetof(struct virtio_pci_mmio, cfg); |
2547 | bar_len = sizeof(((struct virtio_pci_mmio *)0)->cfg); | |
2548 | init_cap(&pci->common, sizeof(pci->common), VIRTIO_PCI_CAP_COMMON_CFG, | |
2549 | bar_offset, bar_len, | |
2550 | offsetof(struct pci_config, notify)); | |
2551 | ||
8dc425ff RR |
2552 | /* |
2553 | * 4.1.4.4.1: | |
2554 | * | |
2555 | * The device MUST present at least one notification capability. | |
2556 | */ | |
93153077 RR |
2557 | bar_offset += bar_len; |
2558 | bar_len = sizeof(((struct virtio_pci_mmio *)0)->notify); | |
8dc425ff RR |
2559 | |
2560 | /* | |
2561 | * 4.1.4.4.1: | |
2562 | * | |
2563 | * The cap.offset MUST be 2-byte aligned. | |
2564 | */ | |
2565 | assert(pci->common.cap_next % 2 == 0); | |
2566 | ||
93153077 | 2567 | /* FIXME: Use a non-zero notify_off, for per-queue notification? */ |
8dc425ff RR |
2568 | /* |
2569 | * 4.1.4.4.1: | |
2570 | * | |
2571 | * The value cap.length presented by the device MUST be at least 2 and | |
2572 | * MUST be large enough to support queue notification offsets for all | |
2573 | * supported queues in all possible configurations. | |
2574 | */ | |
2575 | assert(bar_len >= 2); | |
2576 | ||
93153077 RR |
2577 | init_cap(&pci->notify.cap, sizeof(pci->notify), |
2578 | VIRTIO_PCI_CAP_NOTIFY_CFG, | |
2579 | bar_offset, bar_len, | |
2580 | offsetof(struct pci_config, isr)); | |
2581 | ||
2582 | bar_offset += bar_len; | |
2583 | bar_len = sizeof(((struct virtio_pci_mmio *)0)->isr); | |
8dc425ff RR |
2584 | /* |
2585 | * 4.1.4.5.1: | |
2586 | * | |
2587 | * The device MUST present at least one VIRTIO_PCI_CAP_ISR_CFG | |
2588 | * capability. | |
2589 | */ | |
93153077 RR |
2590 | init_cap(&pci->isr, sizeof(pci->isr), |
2591 | VIRTIO_PCI_CAP_ISR_CFG, | |
2592 | bar_offset, bar_len, | |
2593 | offsetof(struct pci_config, cfg_access)); | |
2594 | ||
8dc425ff RR |
2595 | /* |
2596 | * 4.1.4.7.1: | |
2597 | * | |
2598 | * The device MUST present at least one VIRTIO_PCI_CAP_PCI_CFG | |
2599 | * capability. | |
2600 | */ | |
93153077 RR |
2601 | /* This doesn't have any presence in the BAR */ |
2602 | init_cap(&pci->cfg_access.cap, sizeof(pci->cfg_access), | |
2603 | VIRTIO_PCI_CAP_PCI_CFG, | |
2604 | 0, 0, 0); | |
2605 | ||
2606 | bar_offset += bar_len + sizeof(((struct virtio_pci_mmio *)0)->padding); | |
2607 | assert(bar_offset == sizeof(struct virtio_pci_mmio)); | |
2608 | ||
2609 | /* | |
2610 | * This gets sewn in and length set in set_device_config(). | |
2611 | * Some devices don't have a device configuration interface, so | |
2612 | * we never expose this if we don't call set_device_config(). | |
2613 | */ | |
2614 | init_cap(&pci->device, sizeof(pci->device), VIRTIO_PCI_CAP_DEVICE_CFG, | |
2615 | bar_offset, 0, 0); | |
2616 | } | |
2617 | ||
2e04ef76 | 2618 | /* |
d9028eda RR |
2619 | * This routine does all the creation and setup of a new device, but we don't |
2620 | * actually place the MMIO region until we know the size (if any) of the | |
2621 | * device-specific config. And we don't actually start the service threads | |
2622 | * until later. | |
a6bd8e13 | 2623 | * |
2e04ef76 RR |
2624 | * See what I mean about userspace being boring? |
2625 | */ | |
93153077 RR |
2626 | static struct device *new_pci_device(const char *name, u16 type, |
2627 | u8 class, u8 subclass) | |
2628 | { | |
2629 | struct device *dev = malloc(sizeof(*dev)); | |
2630 | ||
2631 | /* Now we populate the fields one at a time. */ | |
93153077 RR |
2632 | dev->name = name; |
2633 | dev->vq = NULL; | |
93153077 | 2634 | dev->running = false; |
d39a6785 | 2635 | dev->wrote_features_ok = false; |
93153077 RR |
2636 | dev->mmio_size = sizeof(struct virtio_pci_mmio); |
2637 | dev->mmio = calloc(1, dev->mmio_size); | |
2638 | dev->features = (u64)1 << VIRTIO_F_VERSION_1; | |
2639 | dev->features_accepted = 0; | |
2640 | ||
d9028eda | 2641 | if (devices.device_num + 1 >= MAX_PCI_DEVICES) |
93153077 RR |
2642 | errx(1, "Can only handle 31 PCI devices"); |
2643 | ||
2644 | init_pci_config(&dev->config, type, class, subclass); | |
2645 | assert(!devices.pci[devices.device_num+1]); | |
2646 | devices.pci[++devices.device_num] = dev; | |
2647 | ||
2648 | return dev; | |
2649 | } | |
2650 | ||
2e04ef76 RR |
2651 | /* |
2652 | * Our first setup routine is the console. It's a fairly simple device, but | |
2653 | * UNIX tty handling makes it uglier than it could be. | |
2654 | */ | |
17cbca2b | 2655 | static void setup_console(void) |
8ca47e00 RR |
2656 | { |
2657 | struct device *dev; | |
e8330d9b | 2658 | struct virtio_console_config conf; |
8ca47e00 | 2659 | |
dde79789 | 2660 | /* If we can save the initial standard input settings... */ |
8ca47e00 RR |
2661 | if (tcgetattr(STDIN_FILENO, &orig_term) == 0) { |
2662 | struct termios term = orig_term; | |
2e04ef76 RR |
2663 | /* |
2664 | * Then we turn off echo, line buffering and ^C etc: We want a | |
2665 | * raw input stream to the Guest. | |
2666 | */ | |
8ca47e00 RR |
2667 | term.c_lflag &= ~(ISIG|ICANON|ECHO); |
2668 | tcsetattr(STDIN_FILENO, TCSANOW, &term); | |
8ca47e00 RR |
2669 | } |
2670 | ||
ebff0113 | 2671 | dev = new_pci_device("console", VIRTIO_ID_CONSOLE, 0x07, 0x00); |
659a0e66 | 2672 | |
dde79789 | 2673 | /* We store the console state in dev->priv, and initialize it. */ |
8ca47e00 RR |
2674 | dev->priv = malloc(sizeof(struct console_abort)); |
2675 | ((struct console_abort *)dev->priv)->count = 0; | |
8ca47e00 | 2676 | |
2e04ef76 RR |
2677 | /* |
2678 | * The console needs two virtqueues: the input then the output. When | |
56ae43df RR |
2679 | * they put something the input queue, we make sure we're listening to |
2680 | * stdin. When they put something in the output queue, we write it to | |
2e04ef76 RR |
2681 | * stdout. |
2682 | */ | |
17c56d6d RR |
2683 | add_pci_virtqueue(dev, console_input, "input"); |
2684 | add_pci_virtqueue(dev, console_output, "output"); | |
ebff0113 | 2685 | |
e8330d9b RR |
2686 | /* We need a configuration area for the emerg_wr early writes. */ |
2687 | add_pci_feature(dev, VIRTIO_CONSOLE_F_EMERG_WRITE); | |
2688 | set_device_config(dev, &conf, sizeof(conf)); | |
17cbca2b | 2689 | |
ebff0113 | 2690 | verbose("device %u: console\n", devices.device_num); |
8ca47e00 | 2691 | } |
17cbca2b | 2692 | /*:*/ |
8ca47e00 | 2693 | |
2e04ef76 RR |
2694 | /*M:010 |
2695 | * Inter-guest networking is an interesting area. Simplest is to have a | |
17cbca2b RR |
2696 | * --sharenet=<name> option which opens or creates a named pipe. This can be |
2697 | * used to send packets to another guest in a 1:1 manner. | |
dde79789 | 2698 | * |
9f54288d | 2699 | * More sophisticated is to use one of the tools developed for project like UML |
17cbca2b | 2700 | * to do networking. |
dde79789 | 2701 | * |
17cbca2b RR |
2702 | * Faster is to do virtio bonding in kernel. Doing this 1:1 would be |
2703 | * completely generic ("here's my vring, attach to your vring") and would work | |
2704 | * for any traffic. Of course, namespace and permissions issues need to be | |
2705 | * dealt with. A more sophisticated "multi-channel" virtio_net.c could hide | |
2706 | * multiple inter-guest channels behind one interface, although it would | |
2707 | * require some manner of hotplugging new virtio channels. | |
2708 | * | |
9f54288d | 2709 | * Finally, we could use a virtio network switch in the kernel, ie. vhost. |
2e04ef76 | 2710 | :*/ |
8ca47e00 RR |
2711 | |
2712 | static u32 str2ip(const char *ipaddr) | |
2713 | { | |
dec6a2be | 2714 | unsigned int b[4]; |
8ca47e00 | 2715 | |
dec6a2be MM |
2716 | if (sscanf(ipaddr, "%u.%u.%u.%u", &b[0], &b[1], &b[2], &b[3]) != 4) |
2717 | errx(1, "Failed to parse IP address '%s'", ipaddr); | |
2718 | return (b[0] << 24) | (b[1] << 16) | (b[2] << 8) | b[3]; | |
2719 | } | |
2720 | ||
2721 | static void str2mac(const char *macaddr, unsigned char mac[6]) | |
2722 | { | |
2723 | unsigned int m[6]; | |
2724 | if (sscanf(macaddr, "%02x:%02x:%02x:%02x:%02x:%02x", | |
2725 | &m[0], &m[1], &m[2], &m[3], &m[4], &m[5]) != 6) | |
2726 | errx(1, "Failed to parse mac address '%s'", macaddr); | |
2727 | mac[0] = m[0]; | |
2728 | mac[1] = m[1]; | |
2729 | mac[2] = m[2]; | |
2730 | mac[3] = m[3]; | |
2731 | mac[4] = m[4]; | |
2732 | mac[5] = m[5]; | |
8ca47e00 RR |
2733 | } |
2734 | ||
2e04ef76 RR |
2735 | /* |
2736 | * This code is "adapted" from libbridge: it attaches the Host end of the | |
dde79789 RR |
2737 | * network device to the bridge device specified by the command line. |
2738 | * | |
2739 | * This is yet another James Morris contribution (I'm an IP-level guy, so I | |
2e04ef76 RR |
2740 | * dislike bridging), and I just try not to break it. |
2741 | */ | |
8ca47e00 RR |
2742 | static void add_to_bridge(int fd, const char *if_name, const char *br_name) |
2743 | { | |
2744 | int ifidx; | |
2745 | struct ifreq ifr; | |
2746 | ||
2747 | if (!*br_name) | |
2748 | errx(1, "must specify bridge name"); | |
2749 | ||
2750 | ifidx = if_nametoindex(if_name); | |
2751 | if (!ifidx) | |
2752 | errx(1, "interface %s does not exist!", if_name); | |
2753 | ||
2754 | strncpy(ifr.ifr_name, br_name, IFNAMSIZ); | |
dec6a2be | 2755 | ifr.ifr_name[IFNAMSIZ-1] = '\0'; |
8ca47e00 RR |
2756 | ifr.ifr_ifindex = ifidx; |
2757 | if (ioctl(fd, SIOCBRADDIF, &ifr) < 0) | |
2758 | err(1, "can't add %s to bridge %s", if_name, br_name); | |
2759 | } | |
2760 | ||
2e04ef76 RR |
2761 | /* |
2762 | * This sets up the Host end of the network device with an IP address, brings | |
dde79789 | 2763 | * it up so packets will flow, the copies the MAC address into the hwaddr |
2e04ef76 RR |
2764 | * pointer. |
2765 | */ | |
dec6a2be | 2766 | static void configure_device(int fd, const char *tapif, u32 ipaddr) |
8ca47e00 RR |
2767 | { |
2768 | struct ifreq ifr; | |
f846619e | 2769 | struct sockaddr_in sin; |
8ca47e00 RR |
2770 | |
2771 | memset(&ifr, 0, sizeof(ifr)); | |
dec6a2be MM |
2772 | strcpy(ifr.ifr_name, tapif); |
2773 | ||
2774 | /* Don't read these incantations. Just cut & paste them like I did! */ | |
f846619e RR |
2775 | sin.sin_family = AF_INET; |
2776 | sin.sin_addr.s_addr = htonl(ipaddr); | |
2777 | memcpy(&ifr.ifr_addr, &sin, sizeof(sin)); | |
8ca47e00 | 2778 | if (ioctl(fd, SIOCSIFADDR, &ifr) != 0) |
dec6a2be | 2779 | err(1, "Setting %s interface address", tapif); |
8ca47e00 RR |
2780 | ifr.ifr_flags = IFF_UP; |
2781 | if (ioctl(fd, SIOCSIFFLAGS, &ifr) != 0) | |
dec6a2be MM |
2782 | err(1, "Bringing interface %s up", tapif); |
2783 | } | |
2784 | ||
dec6a2be | 2785 | static int get_tun_device(char tapif[IFNAMSIZ]) |
8ca47e00 | 2786 | { |
8ca47e00 | 2787 | struct ifreq ifr; |
bf6d4034 | 2788 | int vnet_hdr_sz; |
dec6a2be MM |
2789 | int netfd; |
2790 | ||
2791 | /* Start with this zeroed. Messy but sure. */ | |
2792 | memset(&ifr, 0, sizeof(ifr)); | |
8ca47e00 | 2793 | |
2e04ef76 RR |
2794 | /* |
2795 | * We open the /dev/net/tun device and tell it we want a tap device. A | |
dde79789 RR |
2796 | * tap device is like a tun device, only somehow different. To tell |
2797 | * the truth, I completely blundered my way through this code, but it | |
2e04ef76 RR |
2798 | * works now! |
2799 | */ | |
8ca47e00 | 2800 | netfd = open_or_die("/dev/net/tun", O_RDWR); |
398f187d | 2801 | ifr.ifr_flags = IFF_TAP | IFF_NO_PI | IFF_VNET_HDR; |
8ca47e00 RR |
2802 | strcpy(ifr.ifr_name, "tap%d"); |
2803 | if (ioctl(netfd, TUNSETIFF, &ifr) != 0) | |
2804 | err(1, "configuring /dev/net/tun"); | |
dec6a2be | 2805 | |
398f187d RR |
2806 | if (ioctl(netfd, TUNSETOFFLOAD, |
2807 | TUN_F_CSUM|TUN_F_TSO4|TUN_F_TSO6|TUN_F_TSO_ECN) != 0) | |
2808 | err(1, "Could not set features for tun device"); | |
2809 | ||
2e04ef76 RR |
2810 | /* |
2811 | * We don't need checksums calculated for packets coming in this | |
2812 | * device: trust us! | |
2813 | */ | |
8ca47e00 RR |
2814 | ioctl(netfd, TUNSETNOCSUM, 1); |
2815 | ||
bf6d4034 RR |
2816 | /* |
2817 | * In virtio before 1.0 (aka legacy virtio), we added a 16-bit | |
2818 | * field at the end of the network header iff | |
2819 | * VIRTIO_NET_F_MRG_RXBUF was negotiated. For virtio 1.0, | |
2820 | * that became the norm, but we need to tell the tun device | |
2821 | * about our expanded header (which is called | |
2822 | * virtio_net_hdr_mrg_rxbuf in the legacy system). | |
2823 | */ | |
206ad06b | 2824 | vnet_hdr_sz = sizeof(struct virtio_net_hdr_v1); |
bf6d4034 RR |
2825 | if (ioctl(netfd, TUNSETVNETHDRSZ, &vnet_hdr_sz) != 0) |
2826 | err(1, "Setting tun header size to %u", vnet_hdr_sz); | |
2827 | ||
dec6a2be MM |
2828 | memcpy(tapif, ifr.ifr_name, IFNAMSIZ); |
2829 | return netfd; | |
2830 | } | |
2831 | ||
2e04ef76 RR |
2832 | /*L:195 |
2833 | * Our network is a Host<->Guest network. This can either use bridging or | |
dec6a2be MM |
2834 | * routing, but the principle is the same: it uses the "tun" device to inject |
2835 | * packets into the Host as if they came in from a normal network card. We | |
2e04ef76 RR |
2836 | * just shunt packets between the Guest and the tun device. |
2837 | */ | |
dec6a2be MM |
2838 | static void setup_tun_net(char *arg) |
2839 | { | |
2840 | struct device *dev; | |
659a0e66 RR |
2841 | struct net_info *net_info = malloc(sizeof(*net_info)); |
2842 | int ipfd; | |
dec6a2be MM |
2843 | u32 ip = INADDR_ANY; |
2844 | bool bridging = false; | |
2845 | char tapif[IFNAMSIZ], *p; | |
2846 | struct virtio_net_config conf; | |
2847 | ||
659a0e66 | 2848 | net_info->tunfd = get_tun_device(tapif); |
dec6a2be | 2849 | |
17cbca2b | 2850 | /* First we create a new network device. */ |
bf6d4034 | 2851 | dev = new_pci_device("net", VIRTIO_ID_NET, 0x02, 0x00); |
659a0e66 | 2852 | dev->priv = net_info; |
dde79789 | 2853 | |
2e04ef76 | 2854 | /* Network devices need a recv and a send queue, just like console. */ |
17c56d6d RR |
2855 | add_pci_virtqueue(dev, net_input, "rx"); |
2856 | add_pci_virtqueue(dev, net_output, "tx"); | |
8ca47e00 | 2857 | |
2e04ef76 RR |
2858 | /* |
2859 | * We need a socket to perform the magic network ioctls to bring up the | |
2860 | * tap interface, connect to the bridge etc. Any socket will do! | |
2861 | */ | |
8ca47e00 RR |
2862 | ipfd = socket(PF_INET, SOCK_DGRAM, IPPROTO_IP); |
2863 | if (ipfd < 0) | |
2864 | err(1, "opening IP socket"); | |
2865 | ||
dde79789 | 2866 | /* If the command line was --tunnet=bridge:<name> do bridging. */ |
8ca47e00 | 2867 | if (!strncmp(BRIDGE_PFX, arg, strlen(BRIDGE_PFX))) { |
dec6a2be MM |
2868 | arg += strlen(BRIDGE_PFX); |
2869 | bridging = true; | |
2870 | } | |
2871 | ||
2872 | /* A mac address may follow the bridge name or IP address */ | |
2873 | p = strchr(arg, ':'); | |
2874 | if (p) { | |
2875 | str2mac(p+1, conf.mac); | |
bf6d4034 | 2876 | add_pci_feature(dev, VIRTIO_NET_F_MAC); |
dec6a2be | 2877 | *p = '\0'; |
dec6a2be MM |
2878 | } |
2879 | ||
2880 | /* arg is now either an IP address or a bridge name */ | |
2881 | if (bridging) | |
2882 | add_to_bridge(ipfd, tapif, arg); | |
2883 | else | |
8ca47e00 RR |
2884 | ip = str2ip(arg); |
2885 | ||
dec6a2be MM |
2886 | /* Set up the tun device. */ |
2887 | configure_device(ipfd, tapif, ip); | |
8ca47e00 | 2888 | |
398f187d | 2889 | /* Expect Guest to handle everything except UFO */ |
bf6d4034 RR |
2890 | add_pci_feature(dev, VIRTIO_NET_F_CSUM); |
2891 | add_pci_feature(dev, VIRTIO_NET_F_GUEST_CSUM); | |
2892 | add_pci_feature(dev, VIRTIO_NET_F_GUEST_TSO4); | |
2893 | add_pci_feature(dev, VIRTIO_NET_F_GUEST_TSO6); | |
2894 | add_pci_feature(dev, VIRTIO_NET_F_GUEST_ECN); | |
2895 | add_pci_feature(dev, VIRTIO_NET_F_HOST_TSO4); | |
2896 | add_pci_feature(dev, VIRTIO_NET_F_HOST_TSO6); | |
2897 | add_pci_feature(dev, VIRTIO_NET_F_HOST_ECN); | |
d1f0132e | 2898 | /* We handle indirect ring entries */ |
bf6d4034 RR |
2899 | add_pci_feature(dev, VIRTIO_RING_F_INDIRECT_DESC); |
2900 | set_device_config(dev, &conf, sizeof(conf)); | |
8ca47e00 | 2901 | |
a586d4f6 | 2902 | /* We don't need the socket any more; setup is done. */ |
8ca47e00 RR |
2903 | close(ipfd); |
2904 | ||
dec6a2be MM |
2905 | if (bridging) |
2906 | verbose("device %u: tun %s attached to bridge: %s\n", | |
2907 | devices.device_num, tapif, arg); | |
2908 | else | |
2909 | verbose("device %u: tun %s: %s\n", | |
2910 | devices.device_num, tapif, arg); | |
8ca47e00 | 2911 | } |
a91d74a3 | 2912 | /*:*/ |
17cbca2b | 2913 | |
e1e72965 | 2914 | /* This hangs off device->priv. */ |
1842f23c | 2915 | struct vblk_info { |
17cbca2b RR |
2916 | /* The size of the file. */ |
2917 | off64_t len; | |
2918 | ||
2919 | /* The file descriptor for the file. */ | |
2920 | int fd; | |
2921 | ||
17cbca2b RR |
2922 | }; |
2923 | ||
e1e72965 RR |
2924 | /*L:210 |
2925 | * The Disk | |
2926 | * | |
a91d74a3 RR |
2927 | * The disk only has one virtqueue, so it only has one thread. It is really |
2928 | * simple: the Guest asks for a block number and we read or write that position | |
2929 | * in the file. | |
2930 | * | |
2931 | * Before we serviced each virtqueue in a separate thread, that was unacceptably | |
2932 | * slow: the Guest waits until the read is finished before running anything | |
2933 | * else, even if it could have been doing useful work. | |
2934 | * | |
2935 | * We could have used async I/O, except it's reputed to suck so hard that | |
2936 | * characters actually go missing from your code when you try to use it. | |
e1e72965 | 2937 | */ |
659a0e66 | 2938 | static void blk_request(struct virtqueue *vq) |
17cbca2b | 2939 | { |
659a0e66 | 2940 | struct vblk_info *vblk = vq->dev->priv; |
17cbca2b | 2941 | unsigned int head, out_num, in_num, wlen; |
c0316a94 | 2942 | int ret, i; |
cb38fa23 | 2943 | u8 *in; |
c0316a94 | 2944 | struct virtio_blk_outhdr out; |
659a0e66 | 2945 | struct iovec iov[vq->vring.num]; |
17cbca2b RR |
2946 | off64_t off; |
2947 | ||
a91d74a3 RR |
2948 | /* |
2949 | * Get the next request, where we normally wait. It triggers the | |
2950 | * interrupt to acknowledge previously serviced requests (if any). | |
2951 | */ | |
659a0e66 | 2952 | head = wait_for_vq_desc(vq, iov, &out_num, &in_num); |
17cbca2b | 2953 | |
c0316a94 | 2954 | /* Copy the output header from the front of the iov (adjusts iov) */ |
1e1c17a7 | 2955 | iov_consume(vq->dev, iov, out_num, &out, sizeof(out)); |
c0316a94 RR |
2956 | |
2957 | /* Find and trim end of iov input array, for our status byte. */ | |
2958 | in = NULL; | |
2959 | for (i = out_num + in_num - 1; i >= out_num; i--) { | |
2960 | if (iov[i].iov_len > 0) { | |
2961 | in = iov[i].iov_base + iov[i].iov_len - 1; | |
2962 | iov[i].iov_len--; | |
2963 | break; | |
2964 | } | |
2965 | } | |
2966 | if (!in) | |
1e1c17a7 | 2967 | bad_driver_vq(vq, "Bad virtblk cmd with no room for status"); |
17cbca2b | 2968 | |
a91d74a3 RR |
2969 | /* |
2970 | * For historical reasons, block operations are expressed in 512 byte | |
2971 | * "sectors". | |
2972 | */ | |
c0316a94 | 2973 | off = out.sector * 512; |
17cbca2b | 2974 | |
50516547 | 2975 | if (out.type & VIRTIO_BLK_T_OUT) { |
2e04ef76 RR |
2976 | /* |
2977 | * Write | |
2978 | * | |
2979 | * Move to the right location in the block file. This can fail | |
2980 | * if they try to write past end. | |
2981 | */ | |
17cbca2b | 2982 | if (lseek64(vblk->fd, off, SEEK_SET) != off) |
c0316a94 | 2983 | err(1, "Bad seek to sector %llu", out.sector); |
17cbca2b | 2984 | |
c0316a94 RR |
2985 | ret = writev(vblk->fd, iov, out_num); |
2986 | verbose("WRITE to sector %llu: %i\n", out.sector, ret); | |
17cbca2b | 2987 | |
2e04ef76 RR |
2988 | /* |
2989 | * Grr... Now we know how long the descriptor they sent was, we | |
17cbca2b | 2990 | * make sure they didn't try to write over the end of the block |
2e04ef76 RR |
2991 | * file (possibly extending it). |
2992 | */ | |
17cbca2b RR |
2993 | if (ret > 0 && off + ret > vblk->len) { |
2994 | /* Trim it back to the correct length */ | |
2995 | ftruncate64(vblk->fd, vblk->len); | |
2996 | /* Die, bad Guest, die. */ | |
1e1c17a7 | 2997 | bad_driver_vq(vq, "Write past end %llu+%u", off, ret); |
17cbca2b | 2998 | } |
7bc9fdda TH |
2999 | |
3000 | wlen = sizeof(*in); | |
3001 | *in = (ret >= 0 ? VIRTIO_BLK_S_OK : VIRTIO_BLK_S_IOERR); | |
c0316a94 | 3002 | } else if (out.type & VIRTIO_BLK_T_FLUSH) { |
7bc9fdda TH |
3003 | /* Flush */ |
3004 | ret = fdatasync(vblk->fd); | |
3005 | verbose("FLUSH fdatasync: %i\n", ret); | |
1200e646 | 3006 | wlen = sizeof(*in); |
cb38fa23 | 3007 | *in = (ret >= 0 ? VIRTIO_BLK_S_OK : VIRTIO_BLK_S_IOERR); |
17cbca2b | 3008 | } else { |
2e04ef76 RR |
3009 | /* |
3010 | * Read | |
3011 | * | |
3012 | * Move to the right location in the block file. This can fail | |
3013 | * if they try to read past end. | |
3014 | */ | |
17cbca2b | 3015 | if (lseek64(vblk->fd, off, SEEK_SET) != off) |
c0316a94 | 3016 | err(1, "Bad seek to sector %llu", out.sector); |
17cbca2b | 3017 | |
c0316a94 | 3018 | ret = readv(vblk->fd, iov + out_num, in_num); |
17cbca2b | 3019 | if (ret >= 0) { |
1200e646 | 3020 | wlen = sizeof(*in) + ret; |
cb38fa23 | 3021 | *in = VIRTIO_BLK_S_OK; |
17cbca2b | 3022 | } else { |
1200e646 | 3023 | wlen = sizeof(*in); |
cb38fa23 | 3024 | *in = VIRTIO_BLK_S_IOERR; |
17cbca2b RR |
3025 | } |
3026 | } | |
3027 | ||
a91d74a3 | 3028 | /* Finished that request. */ |
38bc2b8c | 3029 | add_used(vq, head, wlen); |
17cbca2b RR |
3030 | } |
3031 | ||
e1e72965 | 3032 | /*L:198 This actually sets up a virtual block device. */ |
17cbca2b RR |
3033 | static void setup_block_file(const char *filename) |
3034 | { | |
17cbca2b RR |
3035 | struct device *dev; |
3036 | struct vblk_info *vblk; | |
a586d4f6 | 3037 | struct virtio_blk_config conf; |
17cbca2b | 3038 | |
50516547 RR |
3039 | /* Create the device. */ |
3040 | dev = new_pci_device("block", VIRTIO_ID_BLOCK, 0x01, 0x80); | |
17cbca2b | 3041 | |
e1e72965 | 3042 | /* The device has one virtqueue, where the Guest places requests. */ |
17c56d6d | 3043 | add_pci_virtqueue(dev, blk_request, "request"); |
17cbca2b RR |
3044 | |
3045 | /* Allocate the room for our own bookkeeping */ | |
3046 | vblk = dev->priv = malloc(sizeof(*vblk)); | |
3047 | ||
3048 | /* First we open the file and store the length. */ | |
3049 | vblk->fd = open_or_die(filename, O_RDWR|O_LARGEFILE); | |
3050 | vblk->len = lseek64(vblk->fd, 0, SEEK_END); | |
3051 | ||
3052 | /* Tell Guest how many sectors this device has. */ | |
a586d4f6 | 3053 | conf.capacity = cpu_to_le64(vblk->len / 512); |
17cbca2b | 3054 | |
2e04ef76 RR |
3055 | /* |
3056 | * Tell Guest not to put in too many descriptors at once: two are used | |
3057 | * for the in and out elements. | |
3058 | */ | |
50516547 | 3059 | add_pci_feature(dev, VIRTIO_BLK_F_SEG_MAX); |
a586d4f6 RR |
3060 | conf.seg_max = cpu_to_le32(VIRTQUEUE_NUM - 2); |
3061 | ||
50516547 | 3062 | set_device_config(dev, &conf, sizeof(struct virtio_blk_config)); |
17cbca2b | 3063 | |
17cbca2b | 3064 | verbose("device %u: virtblock %llu sectors\n", |
50516547 | 3065 | devices.device_num, le64_to_cpu(conf.capacity)); |
17cbca2b | 3066 | } |
28fd6d7f | 3067 | |
2e04ef76 | 3068 | /*L:211 |
a454bb36 | 3069 | * Our random number generator device reads from /dev/urandom into the Guest's |
28fd6d7f | 3070 | * input buffers. The usual case is that the Guest doesn't want random numbers |
a454bb36 | 3071 | * and so has no buffers although /dev/urandom is still readable, whereas |
28fd6d7f RR |
3072 | * console is the reverse. |
3073 | * | |
2e04ef76 RR |
3074 | * The same logic applies, however. |
3075 | */ | |
3076 | struct rng_info { | |
3077 | int rfd; | |
3078 | }; | |
3079 | ||
659a0e66 | 3080 | static void rng_input(struct virtqueue *vq) |
28fd6d7f RR |
3081 | { |
3082 | int len; | |
3083 | unsigned int head, in_num, out_num, totlen = 0; | |
659a0e66 RR |
3084 | struct rng_info *rng_info = vq->dev->priv; |
3085 | struct iovec iov[vq->vring.num]; | |
28fd6d7f RR |
3086 | |
3087 | /* First we need a buffer from the Guests's virtqueue. */ | |
659a0e66 | 3088 | head = wait_for_vq_desc(vq, iov, &out_num, &in_num); |
28fd6d7f | 3089 | if (out_num) |
1e1c17a7 | 3090 | bad_driver_vq(vq, "Output buffers in rng?"); |
28fd6d7f | 3091 | |
2e04ef76 | 3092 | /* |
a91d74a3 RR |
3093 | * Just like the console write, we loop to cover the whole iovec. |
3094 | * In this case, short reads actually happen quite a bit. | |
2e04ef76 | 3095 | */ |
28fd6d7f | 3096 | while (!iov_empty(iov, in_num)) { |
659a0e66 | 3097 | len = readv(rng_info->rfd, iov, in_num); |
28fd6d7f | 3098 | if (len <= 0) |
a454bb36 | 3099 | err(1, "Read from /dev/urandom gave %i", len); |
1e1c17a7 | 3100 | iov_consume(vq->dev, iov, in_num, NULL, len); |
28fd6d7f RR |
3101 | totlen += len; |
3102 | } | |
3103 | ||
3104 | /* Tell the Guest about the new input. */ | |
38bc2b8c | 3105 | add_used(vq, head, totlen); |
28fd6d7f RR |
3106 | } |
3107 | ||
2e04ef76 RR |
3108 | /*L:199 |
3109 | * This creates a "hardware" random number device for the Guest. | |
3110 | */ | |
28fd6d7f RR |
3111 | static void setup_rng(void) |
3112 | { | |
3113 | struct device *dev; | |
659a0e66 | 3114 | struct rng_info *rng_info = malloc(sizeof(*rng_info)); |
28fd6d7f | 3115 | |
a454bb36 RR |
3116 | /* Our device's private info simply contains the /dev/urandom fd. */ |
3117 | rng_info->rfd = open_or_die("/dev/urandom", O_RDONLY); | |
28fd6d7f | 3118 | |
2e04ef76 | 3119 | /* Create the new device. */ |
0d5b5d39 | 3120 | dev = new_pci_device("rng", VIRTIO_ID_RNG, 0xff, 0); |
659a0e66 | 3121 | dev->priv = rng_info; |
28fd6d7f RR |
3122 | |
3123 | /* The device has one virtqueue, where the Guest places inbufs. */ | |
17c56d6d | 3124 | add_pci_virtqueue(dev, rng_input, "input"); |
28fd6d7f | 3125 | |
0d5b5d39 RR |
3126 | /* We don't have any configuration space */ |
3127 | no_device_config(dev); | |
3128 | ||
3129 | verbose("device %u: rng\n", devices.device_num); | |
28fd6d7f | 3130 | } |
a6bd8e13 | 3131 | /* That's the end of device setup. */ |
ec04b13f | 3132 | |
a6bd8e13 | 3133 | /*L:230 Reboot is pretty easy: clean up and exec() the Launcher afresh. */ |
ec04b13f BR |
3134 | static void __attribute__((noreturn)) restart_guest(void) |
3135 | { | |
3136 | unsigned int i; | |
3137 | ||
2e04ef76 RR |
3138 | /* |
3139 | * Since we don't track all open fds, we simply close everything beyond | |
3140 | * stderr. | |
3141 | */ | |
ec04b13f BR |
3142 | for (i = 3; i < FD_SETSIZE; i++) |
3143 | close(i); | |
8c79873d | 3144 | |
659a0e66 RR |
3145 | /* Reset all the devices (kills all threads). */ |
3146 | cleanup_devices(); | |
3147 | ||
ec04b13f BR |
3148 | execv(main_args[0], main_args); |
3149 | err(1, "Could not exec %s", main_args[0]); | |
3150 | } | |
8ca47e00 | 3151 | |
2e04ef76 RR |
3152 | /*L:220 |
3153 | * Finally we reach the core of the Launcher which runs the Guest, serves | |
3154 | * its input and output, and finally, lays it to rest. | |
3155 | */ | |
56739c80 | 3156 | static void __attribute__((noreturn)) run_guest(void) |
8ca47e00 RR |
3157 | { |
3158 | for (;;) { | |
69a09dc1 | 3159 | struct lguest_pending notify; |
8ca47e00 RR |
3160 | int readval; |
3161 | ||
3162 | /* We read from the /dev/lguest device to run the Guest. */ | |
69a09dc1 | 3163 | readval = pread(lguest_fd, ¬ify, sizeof(notify), cpu_id); |
69a09dc1 | 3164 | if (readval == sizeof(notify)) { |
00f8d546 | 3165 | if (notify.trap == 13) { |
c565650b RR |
3166 | verbose("Emulating instruction at %#x\n", |
3167 | getreg(eip)); | |
3168 | emulate_insn(notify.insn); | |
6a54f9ab RR |
3169 | } else if (notify.trap == 14) { |
3170 | verbose("Emulating MMIO at %#x\n", | |
3171 | getreg(eip)); | |
3172 | emulate_mmio(notify.addr, notify.insn); | |
69a09dc1 RR |
3173 | } else |
3174 | errx(1, "Unknown trap %i addr %#08x\n", | |
3175 | notify.trap, notify.addr); | |
dde79789 | 3176 | /* ENOENT means the Guest died. Reading tells us why. */ |
8ca47e00 RR |
3177 | } else if (errno == ENOENT) { |
3178 | char reason[1024] = { 0 }; | |
e3283fa0 | 3179 | pread(lguest_fd, reason, sizeof(reason)-1, cpu_id); |
8ca47e00 | 3180 | errx(1, "%s", reason); |
ec04b13f BR |
3181 | /* ERESTART means that we need to reboot the guest */ |
3182 | } else if (errno == ERESTART) { | |
3183 | restart_guest(); | |
659a0e66 RR |
3184 | /* Anything else means a bug or incompatible change. */ |
3185 | } else | |
8ca47e00 | 3186 | err(1, "Running guest failed"); |
8ca47e00 RR |
3187 | } |
3188 | } | |
a6bd8e13 | 3189 | /*L:240 |
e1e72965 RR |
3190 | * This is the end of the Launcher. The good news: we are over halfway |
3191 | * through! The bad news: the most fiendish part of the code still lies ahead | |
3192 | * of us. | |
dde79789 | 3193 | * |
e1e72965 RR |
3194 | * Are you ready? Take a deep breath and join me in the core of the Host, in |
3195 | * "make Host". | |
2e04ef76 | 3196 | :*/ |
8ca47e00 RR |
3197 | |
3198 | static struct option opts[] = { | |
3199 | { "verbose", 0, NULL, 'v' }, | |
8ca47e00 RR |
3200 | { "tunnet", 1, NULL, 't' }, |
3201 | { "block", 1, NULL, 'b' }, | |
28fd6d7f | 3202 | { "rng", 0, NULL, 'r' }, |
8ca47e00 | 3203 | { "initrd", 1, NULL, 'i' }, |
8aeb36e8 PS |
3204 | { "username", 1, NULL, 'u' }, |
3205 | { "chroot", 1, NULL, 'c' }, | |
8ca47e00 RR |
3206 | { NULL }, |
3207 | }; | |
3208 | static void usage(void) | |
3209 | { | |
3210 | errx(1, "Usage: lguest [--verbose] " | |
dec6a2be | 3211 | "[--tunnet=(<ipaddr>:<macaddr>|bridge:<bridgename>:<macaddr>)\n" |
8ca47e00 RR |
3212 | "|--block=<filename>|--initrd=<filename>]...\n" |
3213 | "<mem-in-mb> vmlinux [args...]"); | |
3214 | } | |
3215 | ||
3c6b5bfa | 3216 | /*L:105 The main routine is where the real work begins: */ |
8ca47e00 RR |
3217 | int main(int argc, char *argv[]) |
3218 | { | |
2e04ef76 | 3219 | /* Memory, code startpoint and size of the (optional) initrd. */ |
58a24566 | 3220 | unsigned long mem = 0, start, initrd_size = 0; |
56739c80 RR |
3221 | /* Two temporaries. */ |
3222 | int i, c; | |
3c6b5bfa | 3223 | /* The boot information for the Guest. */ |
43d33b21 | 3224 | struct boot_params *boot; |
dde79789 | 3225 | /* If they specify an initrd file to load. */ |
8ca47e00 RR |
3226 | const char *initrd_name = NULL; |
3227 | ||
8aeb36e8 PS |
3228 | /* Password structure for initgroups/setres[gu]id */ |
3229 | struct passwd *user_details = NULL; | |
3230 | ||
3231 | /* Directory to chroot to */ | |
3232 | char *chroot_path = NULL; | |
3233 | ||
ec04b13f BR |
3234 | /* Save the args: we "reboot" by execing ourselves again. */ |
3235 | main_args = argv; | |
ec04b13f | 3236 | |
2e04ef76 | 3237 | /* |
d9028eda RR |
3238 | * First we initialize the device list. We remember next interrupt |
3239 | * number to use for devices (1: remember that 0 is used by the timer). | |
2e04ef76 | 3240 | */ |
17cbca2b | 3241 | devices.next_irq = 1; |
8ca47e00 | 3242 | |
a91d74a3 | 3243 | /* We're CPU 0. In fact, that's the only CPU possible right now. */ |
e3283fa0 | 3244 | cpu_id = 0; |
a91d74a3 | 3245 | |
2e04ef76 RR |
3246 | /* |
3247 | * We need to know how much memory so we can set up the device | |
dde79789 RR |
3248 | * descriptor and memory pages for the devices as we parse the command |
3249 | * line. So we quickly look through the arguments to find the amount | |
2e04ef76 RR |
3250 | * of memory now. |
3251 | */ | |
6570c459 RR |
3252 | for (i = 1; i < argc; i++) { |
3253 | if (argv[i][0] != '-') { | |
3c6b5bfa | 3254 | mem = atoi(argv[i]) * 1024 * 1024; |
2e04ef76 RR |
3255 | /* |
3256 | * We start by mapping anonymous pages over all of | |
3c6b5bfa RR |
3257 | * guest-physical memory range. This fills it with 0, |
3258 | * and ensures that the Guest won't be killed when it | |
2e04ef76 RR |
3259 | * tries to access it. |
3260 | */ | |
3c6b5bfa RR |
3261 | guest_base = map_zeroed_pages(mem / getpagesize() |
3262 | + DEVICE_PAGES); | |
3263 | guest_limit = mem; | |
0a6bcc18 | 3264 | guest_max = guest_mmio = mem + DEVICE_PAGES*getpagesize(); |
6570c459 RR |
3265 | break; |
3266 | } | |
3267 | } | |
dde79789 | 3268 | |
713e3f72 RR |
3269 | /* We always have a console device, and it's always device 1. */ |
3270 | setup_console(); | |
3271 | ||
dde79789 | 3272 | /* The options are fairly straight-forward */ |
8ca47e00 RR |
3273 | while ((c = getopt_long(argc, argv, "v", opts, NULL)) != EOF) { |
3274 | switch (c) { | |
3275 | case 'v': | |
3276 | verbose = true; | |
3277 | break; | |
8ca47e00 | 3278 | case 't': |
17cbca2b | 3279 | setup_tun_net(optarg); |
8ca47e00 RR |
3280 | break; |
3281 | case 'b': | |
17cbca2b | 3282 | setup_block_file(optarg); |
8ca47e00 | 3283 | break; |
28fd6d7f RR |
3284 | case 'r': |
3285 | setup_rng(); | |
3286 | break; | |
8ca47e00 RR |
3287 | case 'i': |
3288 | initrd_name = optarg; | |
3289 | break; | |
8aeb36e8 PS |
3290 | case 'u': |
3291 | user_details = getpwnam(optarg); | |
3292 | if (!user_details) | |
3293 | err(1, "getpwnam failed, incorrect username?"); | |
3294 | break; | |
3295 | case 'c': | |
3296 | chroot_path = optarg; | |
3297 | break; | |
8ca47e00 RR |
3298 | default: |
3299 | warnx("Unknown argument %s", argv[optind]); | |
3300 | usage(); | |
3301 | } | |
3302 | } | |
2e04ef76 RR |
3303 | /* |
3304 | * After the other arguments we expect memory and kernel image name, | |
3305 | * followed by command line arguments for the kernel. | |
3306 | */ | |
8ca47e00 RR |
3307 | if (optind + 2 > argc) |
3308 | usage(); | |
3309 | ||
3c6b5bfa RR |
3310 | verbose("Guest base is at %p\n", guest_base); |
3311 | ||
8e709469 RR |
3312 | /* Initialize the (fake) PCI host bridge device. */ |
3313 | init_pci_host_bridge(); | |
3314 | ||
8ca47e00 | 3315 | /* Now we load the kernel */ |
47436aa4 | 3316 | start = load_kernel(open_or_die(argv[optind+1], O_RDONLY)); |
8ca47e00 | 3317 | |
3c6b5bfa RR |
3318 | /* Boot information is stashed at physical address 0 */ |
3319 | boot = from_guest_phys(0); | |
3320 | ||
dde79789 | 3321 | /* Map the initrd image if requested (at top of physical memory) */ |
8ca47e00 RR |
3322 | if (initrd_name) { |
3323 | initrd_size = load_initrd(initrd_name, mem); | |
2e04ef76 RR |
3324 | /* |
3325 | * These are the location in the Linux boot header where the | |
3326 | * start and size of the initrd are expected to be found. | |
3327 | */ | |
43d33b21 RR |
3328 | boot->hdr.ramdisk_image = mem - initrd_size; |
3329 | boot->hdr.ramdisk_size = initrd_size; | |
dde79789 | 3330 | /* The bootloader type 0xFF means "unknown"; that's OK. */ |
43d33b21 | 3331 | boot->hdr.type_of_loader = 0xFF; |
8ca47e00 RR |
3332 | } |
3333 | ||
2e04ef76 RR |
3334 | /* |
3335 | * The Linux boot header contains an "E820" memory map: ours is a | |
3336 | * simple, single region. | |
3337 | */ | |
43d33b21 RR |
3338 | boot->e820_entries = 1; |
3339 | boot->e820_map[0] = ((struct e820entry) { 0, mem, E820_RAM }); | |
2e04ef76 RR |
3340 | /* |
3341 | * The boot header contains a command line pointer: we put the command | |
3342 | * line after the boot header. | |
3343 | */ | |
43d33b21 | 3344 | boot->hdr.cmd_line_ptr = to_guest_phys(boot + 1); |
e1e72965 | 3345 | /* We use a simple helper to copy the arguments separated by spaces. */ |
43d33b21 | 3346 | concat((char *)(boot + 1), argv+optind+2); |
dde79789 | 3347 | |
e22a5398 RR |
3348 | /* Set kernel alignment to 16M (CONFIG_PHYSICAL_ALIGN) */ |
3349 | boot->hdr.kernel_alignment = 0x1000000; | |
3350 | ||
814a0e5c | 3351 | /* Boot protocol version: 2.07 supports the fields for lguest. */ |
43d33b21 | 3352 | boot->hdr.version = 0x207; |
814a0e5c RR |
3353 | |
3354 | /* The hardware_subarch value of "1" tells the Guest it's an lguest. */ | |
43d33b21 | 3355 | boot->hdr.hardware_subarch = 1; |
814a0e5c | 3356 | |
43d33b21 RR |
3357 | /* Tell the entry path not to try to reload segment registers. */ |
3358 | boot->hdr.loadflags |= KEEP_SEGMENTS; | |
8ca47e00 | 3359 | |
9f54288d | 3360 | /* We tell the kernel to initialize the Guest. */ |
56739c80 | 3361 | tell_kernel(start); |
dde79789 | 3362 | |
a91d74a3 | 3363 | /* Ensure that we terminate if a device-servicing child dies. */ |
659a0e66 RR |
3364 | signal(SIGCHLD, kill_launcher); |
3365 | ||
3366 | /* If we exit via err(), this kills all the threads, restores tty. */ | |
3367 | atexit(cleanup_devices); | |
8ca47e00 | 3368 | |
8aeb36e8 PS |
3369 | /* If requested, chroot to a directory */ |
3370 | if (chroot_path) { | |
3371 | if (chroot(chroot_path) != 0) | |
3372 | err(1, "chroot(\"%s\") failed", chroot_path); | |
3373 | ||
3374 | if (chdir("/") != 0) | |
3375 | err(1, "chdir(\"/\") failed"); | |
3376 | ||
3377 | verbose("chroot done\n"); | |
3378 | } | |
3379 | ||
3380 | /* If requested, drop privileges */ | |
3381 | if (user_details) { | |
3382 | uid_t u; | |
3383 | gid_t g; | |
3384 | ||
3385 | u = user_details->pw_uid; | |
3386 | g = user_details->pw_gid; | |
3387 | ||
3388 | if (initgroups(user_details->pw_name, g) != 0) | |
3389 | err(1, "initgroups failed"); | |
3390 | ||
3391 | if (setresgid(g, g, g) != 0) | |
3392 | err(1, "setresgid failed"); | |
3393 | ||
3394 | if (setresuid(u, u, u) != 0) | |
3395 | err(1, "setresuid failed"); | |
3396 | ||
3397 | verbose("Dropping privileges completed\n"); | |
3398 | } | |
3399 | ||
dde79789 | 3400 | /* Finally, run the Guest. This doesn't return. */ |
56739c80 | 3401 | run_guest(); |
8ca47e00 | 3402 | } |
f56a384e RR |
3403 | /*:*/ |
3404 | ||
3405 | /*M:999 | |
3406 | * Mastery is done: you now know everything I do. | |
3407 | * | |
3408 | * But surely you have seen code, features and bugs in your wanderings which | |
3409 | * you now yearn to attack? That is the real game, and I look forward to you | |
3410 | * patching and forking lguest into the Your-Name-Here-visor. | |
3411 | * | |
3412 | * Farewell, and good coding! | |
3413 | * Rusty Russell. | |
3414 | */ |