Hello,
I am trying to use FunctionFS on the beagleboard black using configfs. The test I am running has worked on a Xilinx ZC706 board but is failing on the bbb when I run the ffs-test command with the following error:
[ 175.247507] BUG: spinlock bad magic on CPU#0, ffs-test/1341
[ 175.253382] lock: 0xddf3b1c0, .magic: ddf3b1c0, .owner: /-1, .owner_cpu: -658631644
[ 175.262056] CPU: 0 PID: 1341 Comm: ffs-test Not tainted 4.1.0-rc7-bone70 #5
[ 175.269354] Hardware name: Generic AM33XX (Flattened Device Tree)
[ 175.275770] [] (unwind_backtrace) from [] (show_stack+0xb/0xc)
[ 175.283718] [] (show_stack) from [] (dump_stack+0x53/0x68)
[ 175.291305] [] (dump_stack) from [] (do_raw_spin_lock+0x101/0x138)
[ 175.299622] [] (do_raw_spin_lock) from [] (_raw_spin_lock_irqsave+0xd/0x10)
[ 175.308756] [] (_raw_spin_lock_irqsave) from [] (kiocb_set_cancel_fn+0x13/0x3c)
[ 175.318269] [] (kiocb_set_cancel_fn) from [] (ffs_epfile_read_iter+0x56/0xd4 [usb_f_fs])
[ 175.328593] [] (ffs_epfile_read_iter [usb_f_fs]) from [] (__vfs_read+0x69/0x84)
[ 175.338085] [] (__vfs_read) from [] (vfs_read+0x4d/0xec)
[ 175.345479] [] (vfs_read) from [] (SyS_read+0x2d/0x64)
[ 175.352698] [] (SyS_read) from [] (ret_fast_syscall+0x1/0x4c)
[ 188.310460] BUG: spinlock lockup suspected on CPU#0, ffs-test/1341
[ 188.316942] lock: 0xddf3b1c0, .magic: ddf3b1c0, .owner: /-1, .owner_cpu: -658631644
[ 188.325610] CPU: 0 PID: 1341 Comm: ffs-test Not tainted 4.1.0-rc7-bone70 #5
[ 188.332909] Hardware name: Generic AM33XX (Flattened Device Tree)
[ 188.339303] [] (unwind_backtrace) from [] (show_stack+0xb/0xc)
[ 188.347244] [] (show_stack) from [] (dump_stack+0x53/0x68)
[ 188.354822] [] (dump_stack) from [] (do_raw_spin_lock+0xcf/0x138)
[ 188.363040] [] (do_raw_spin_lock) from [] (_raw_spin_lock_irqsave+0xd/0x10)
[ 188.372167] [] (_raw_spin_lock_irqsave) from [] (kiocb_set_cancel_fn+0x13/0x3c)
[ 188.381663] [] (kiocb_set_cancel_fn) from [] (ffs_epfile_read_iter+0x56/0xd4 [usb_f_fs])
[ 188.391978] [] (ffs_epfile_read_iter [usb_f_fs]) from [] (__vfs_read+0x69/0x84)
[ 188.401467] [] (__vfs_read) from [] (vfs_read+0x4d/0xec)
[ 188.408861] [] (vfs_read) from [] (SyS_read+0x2d/0x64)
[ 188.416074] [] (SyS_read) from [] (ret_fast_syscall+0x1/0x4c)
The mounting script is:
modprobe libcomposite
modprobe usb_f_fs
mkdir /dev/cfg
mount -t configfs configfs /dev/cfg
mkdir /dev/cfg/usb_gadget/g1
echo “0x2341” > /dev/cfg/usb_gadget/g1/idVendor
echo “0x01AA” > /dev/cfg/usb_gadget/g1/idProduct
mkdir /dev/cfg/usb_gadget/g1/functions/ffs.usb0
mkdir /dev/cfg/usb_gadget/g1/configs/c.1
ln -s /dev/cfg/usb_gadget/g1/functions/ffs.usb0 /dev/cfg/usb_gadget/g1/configs/c.1
echo 0xcd > /dev/cfg/usb_gadget/g1/os_desc/b_vendor_code
echo MSFT100 > /dev/cfg/usb_gadget/g1/os_desc/qw_sign
echo 0 > /dev/cfg/usb_gadget/g1/os_desc/use
echo 0x200 > /dev/cfg/usb_gadget/g1/bcdUSB
mkdir /dev/cfg/usb_gadget/g1/strings/0x409
echo “serialnumber” > /dev/cfg/usb_gadget/g1/strings/0x409/serialnumber
echo “manufacturer” > /dev/cfg/usb_gadget/g1/strings/0x409/manufacturer
echo “Test Device” > /dev/cfg/usb_gadget/g1/strings/0x409/product
mkdir /dev/ffs
mount -t functionfs usb0 /dev/ffs
The code for the test program is:
/* $(CROSS_COMPILE)cc -Wall -Wextra -g -o ffs-test ffs-test.c -lpthread */
#define _BSD_SOURCE /* for endian.h */
#include <endian.h>
#include <errno.h>
#include <fcntl.h>
#include <pthread.h>
#include <stdarg.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/ioctl.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>
#include “le_byteshift.h”
//#include “…/…/include/uapi/linux/usb/functionfs.h”
#include “functionfs.h”
/******************** Little Endian Handling ********************************/
#define cpu_to_le16(x) htole16(x)
#define cpu_to_le32(x) htole32(x)
#define le32_to_cpu(x) le32toh(x)
#define le16_to_cpu(x) le16toh(x)
/******************** Messages and Errors ***********************************/
static const char argv0[] = “ffs-test”;
static unsigned verbosity = 7;
static void _msg(unsigned level, const char *fmt, …)
{
if (level < 2)
level = 2;
else if (level > 7)
level = 7;
if (level <= verbosity) {
static const char levels[8][6] = {
[2] = “crit:”,
[3] = "err: ",
[4] = “warn:”,
[5] = “note:”,
[6] = “info:”,
[7] = "dbg: "
};
int _errno = errno;
va_list ap;
fprintf(stderr, "%s: %s ", argv0, levels[level]);
va_start(ap, fmt);
vfprintf(stderr, fmt, ap);
va_end(ap);
if (fmt[strlen(fmt) - 1] != ‘\n’) {
char buffer[128];
strerror_r(_errno, buffer, sizeof buffer);
fprintf(stderr, “: (-%d) %s\n”, _errno, buffer);
}
fflush(stderr);
}
}
#define die(…) (_msg(2, VA_ARGS), exit(1))
#define err(…) _msg(3, VA_ARGS)
#define warn(…) _msg(4, VA_ARGS)
#define note(…) _msg(5, VA_ARGS)
#define info(…) _msg(6, VA_ARGS)
#define debug(…) _msg(7, VA_ARGS)
#define die_on(cond, …) do {
if (cond)
die(VA_ARGS);
} while (0)
/******************** Descriptors and Strings *******************************/
static const struct {
struct usb_functionfs_descs_head_v2 header;
__le32 fs_count;
__le32 hs_count;
//__le32 os_count;
struct {
struct usb_interface_descriptor intf;
struct usb_endpoint_descriptor_no_audio sink;
struct usb_endpoint_descriptor_no_audio source;
} attribute((packed)) fs_descs, hs_descs;
/*struct {
struct usb_os_desc_header header;
struct usb_ext_compat_desc function;
} attribute((packed)) os_compat;
struct {
struct usb_os_desc_header header;
struct usb_ext_prop_desc desc;
char bPropertyName[20];
__le32 wPropertyDataLength;
char bPropertyData[39];
} attribute((packed)) os_prop;*/
} attribute((packed)) descriptors = {
.header = {
.magic = cpu_to_le32(FUNCTIONFS_DESCRIPTORS_MAGIC_V2),
.flags = cpu_to_le32(FUNCTIONFS_HAS_FS_DESC |
FUNCTIONFS_HAS_HS_DESC
/| FUNCTIONFS_HAS_MS_OS_DESC/),
.length = cpu_to_le32(sizeof descriptors),
},
.fs_count = cpu_to_le32(3),
.fs_descs = {
.intf = {
.bLength = sizeof descriptors.fs_descs.intf,
.bDescriptorType = USB_DT_INTERFACE,
.bNumEndpoints = 2,
.bInterfaceClass = USB_CLASS_VENDOR_SPEC,
.iInterface = 0,
},
.sink = {
.bLength = sizeof descriptors.fs_descs.sink,
.bDescriptorType = USB_DT_ENDPOINT,
.bEndpointAddress = 1 | USB_DIR_IN,
.bmAttributes = USB_ENDPOINT_XFER_BULK,
/* .wMaxPacketSize = autoconfiguration (kernel) /
},
.source = {
.bLength = sizeof descriptors.fs_descs.source,
.bDescriptorType = USB_DT_ENDPOINT,
.bEndpointAddress = 2 | USB_DIR_OUT,
.bmAttributes = USB_ENDPOINT_XFER_BULK,
/ .wMaxPacketSize = autoconfiguration (kernel) /
},
},
.hs_count = cpu_to_le32(3),
.hs_descs = {
.intf = {
.bLength = sizeof descriptors.fs_descs.intf,
.bDescriptorType = USB_DT_INTERFACE,
.bNumEndpoints = 2,
.bInterfaceClass = USB_CLASS_VENDOR_SPEC,
.iInterface = 0,
},
.sink = {
.bLength = sizeof descriptors.hs_descs.sink,
.bDescriptorType = USB_DT_ENDPOINT,
.bEndpointAddress = 1 | USB_DIR_IN,
.bmAttributes = USB_ENDPOINT_XFER_BULK,
.wMaxPacketSize = cpu_to_le16(512),
},
.source = {
.bLength = sizeof descriptors.hs_descs.source,
.bDescriptorType = USB_DT_ENDPOINT,
.bEndpointAddress = 2 | USB_DIR_OUT,
.bmAttributes = USB_ENDPOINT_XFER_BULK,
.wMaxPacketSize = cpu_to_le16(512),
.bInterval = 1, / NAK every 1 uframe /
},
},
/.os_count = cpu_to_le32(1),
.os_compat = {
.header = {
.interface=0,
.dwLength=sizeof descriptors.os_compat,
.bcdVersion = cpu_to_le16(0x01),
.wIndex = cpu_to_le16(0x0004),
.bCount = (0x01)
},
.function = {
.bFirstInterfaceNumber = 0,
.CompatibleID=“WINUSB”,
}
}
.os_prop = {
.header= {
.interface=0,
.dwLength = sizeof descriptors.os_prop,
.bcdVersion = cpu_to_le16(0x01),
.wIndex = cpu_to_le16(0x0005),
.wCount = cpu_to_le16(0x0001),
},
.desc = {
.dwSize=cpu_to_le32(sizeof(descriptors.os_prop.desc)
+sizeof(descriptors.os_prop.bPropertyName)
+sizeof (descriptors.os_prop.wPropertyDataLength)
+sizeof(descriptors.os_prop.bPropertyData)),
.dwPropertyDataType = cpu_to_le32(1),
.wPropertyNameLength = cpu_to_le16(20),
},
.bPropertyName=“DeviceInterfaceGUID”,
.wPropertyDataLength = cpu_to_le32(39),
.bPropertyData="{7D220264-E146-4540-ADE3-56797D199CB2}"
}*/
};
static size_t descs_to_legacy(void **legacy, const void *descriptors_v2)
{
const unsigned char *descs_end, *descs_start;
__u32 length, fs_count = 0, hs_count = 0, count;
/* Read v2 header */
{
const struct {
const struct usb_functionfs_descs_head_v2 header;
const __le32 counts[];
} attribute((packed)) *const in = descriptors_v2;
const __le32 *counts = in->counts;
__u32 flags;
if (le32_to_cpu(in->header.magic) !=
FUNCTIONFS_DESCRIPTORS_MAGIC_V2)
return 0;
length = le32_to_cpu(in->header.length);
if (length <= sizeof in->header)
return 0;
length -= sizeof in->header;
flags = le32_to_cpu(in->header.flags);
if (flags & ~(FUNCTIONFS_HAS_FS_DESC | FUNCTIONFS_HAS_HS_DESC |
FUNCTIONFS_HAS_SS_DESC))
return 0;
#define GET_NEXT_COUNT_IF_FLAG(ret, flg) do {
if (!(flags & (flg)))
break;
if (length < 4)
return 0;
ret = le32_to_cpu(*counts);
length -= 4;
++counts;
} while (0)
GET_NEXT_COUNT_IF_FLAG(fs_count, FUNCTIONFS_HAS_FS_DESC);
GET_NEXT_COUNT_IF_FLAG(hs_count, FUNCTIONFS_HAS_HS_DESC);
GET_NEXT_COUNT_IF_FLAG(count, FUNCTIONFS_HAS_SS_DESC);
count = fs_count + hs_count;
if (!count)
return 0;
descs_start = (const void *)counts;
#undef GET_NEXT_COUNT_IF_FLAG
}
/*
- Find the end of FS and HS USB descriptors. SS descriptors
- are ignored since legacy format does not support them.
*/
descs_end = descs_start;
do {
if (length < *descs_end)
return 0;
length -= *descs_end;
descs_end += *descs_end;
} while (–count);
/* Allocate legacy descriptors and copy the data. */
{
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored “-Wdeprecated-declarations”
struct {
struct usb_functionfs_descs_head header;
__u8 descriptors[];
} attribute((packed)) *out;
#pragma GCC diagnostic pop
length = sizeof out->header + (descs_end - descs_start);
out = malloc(length);
out->header.magic = cpu_to_le32(FUNCTIONFS_DESCRIPTORS_MAGIC);
out->header.length = cpu_to_le32(length);
out->header.fs_count = cpu_to_le32(fs_count);
out->header.hs_count = cpu_to_le32(hs_count);
memcpy(out->descriptors, descs_start, descs_end - descs_start);
*legacy = out;
}
return length;
}
#define STR_INTERFACE_ “Source/Sink”
static const struct {
struct usb_functionfs_strings_head header;
struct {
le16 code;
const char str1[sizeof STR_INTERFACE];
} attribute((packed)) lang0;
} attribute((packed)) strings = {
.header = {
.magic = cpu_to_le32(FUNCTIONFS_STRINGS_MAGIC),
.length = cpu_to_le32(sizeof strings),
.str_count = cpu_to_le32(1),
.lang_count = cpu_to_le32(1),
},
.lang0 = {
cpu_to_le16(0x0409), /* en-us */
STR_INTERFACE,
},
};
#define STR_INTERFACE strings.lang0.str1
/******************** Files and Threads Handling ****************************/
struct thread;
static ssize_t read_wrap(struct thread *t, void *buf, size_t nbytes);
static ssize_t write_wrap(struct thread *t, const void *buf, size_t nbytes);
static ssize_t ep0_consume(struct thread *t, const void *buf, size_t nbytes);
static ssize_t fill_in_buf(struct thread *t, void *buf, size_t nbytes);
static ssize_t empty_out_buf(struct thread *t, const void *buf, size_t nbytes);
static struct thread {
const char *const filename;
size_t buf_size;
ssize_t (*in)(struct thread *, void *, size_t);
const char *const in_name;
ssize_t (*out)(struct thread *, const void *, size_t);
const char *const out_name;
int fd;
pthread_t id;
void *buf;
ssize_t status;
} threads[] = {
{
“ep0”, 4 * sizeof(struct usb_functionfs_event),
read_wrap, NULL,
ep0_consume, “”,
0, 0, NULL, 0
},
{
“ep1”, 8 * 1024,
fill_in_buf, “”,
write_wrap, NULL,
0, 0, NULL, 0
},
{
“ep2”, 8 * 1024,
read_wrap, NULL,
empty_out_buf, “”,
0, 0, NULL, 0
},
};
static void init_thread(struct thread *t)
{
t->buf = malloc(t->buf_size);
die_on(!t->buf, “malloc”);
t->fd = open(t->filename, O_RDWR);
die_on(t->fd < 0, “%s”, t->filename);
}
static void cleanup_thread(void *arg)
{
struct thread *t = arg;
int ret, fd;
fd = t->fd;
if (t->fd < 0)
return;
t->fd = -1;
/* test the FIFO ioctls (non-ep0 code paths) /
if (t != threads) {
ret = ioctl(fd, FUNCTIONFS_FIFO_STATUS);
if (ret < 0) {
/ ENODEV reported after disconnect */
if (errno != ENODEV)
err("%s: get fifo status", t->filename);
} else if (ret) {
warn("%s: unclaimed = %d\n", t->filename, ret);
if (ioctl(fd, FUNCTIONFS_FIFO_FLUSH) < 0)
err("%s: fifo flush", t->filename);
}
}
if (close(fd) < 0)
err("%s: close", t->filename);
free(t->buf);
t->buf = NULL;
}
static void *start_thread_helper(void *arg)
{
const char *name, *op, *in_name, *out_name;
struct thread *t = arg;
ssize_t ret;
info("%s: starts\n", t->filename);
in_name = t->in_name ? t->in_name : t->filename;
out_name = t->out_name ? t->out_name : t->filename;
pthread_cleanup_push(cleanup_thread, arg);
for (;
{
pthread_testcancel();
ret = t->in(t, t->buf, t->buf_size);
if (ret > 0) {
ret = t->out(t, t->buf, ret);
name = out_name;
op = “write”;
} else {
name = in_name;
op = “read”;
}
if (ret > 0) {
/* nop */
} else if (!ret) {
debug("%s: %s: EOF", name, op);
break;
} else if (errno == EINTR || errno == EAGAIN) {
debug("%s: %s", name, op);
} else {
warn("%s: %s", name, op);
break;
}
}
pthread_cleanup_pop(1);
t->status = ret;
info("%s: ends\n", t->filename);
return NULL;
}
static void start_thread(struct thread *t)
{
debug("%s: starting\n", t->filename);
die_on(pthread_create(&t->id, NULL, start_thread_helper, t) < 0,
“pthread_create(%s)”, t->filename);
}
static void join_thread(struct thread *t)
{
int ret = pthread_join(t->id, NULL);
if (ret < 0)
err("%s: joining thread", t->filename);
else
debug("%s: joined\n", t->filename);
}
static ssize_t read_wrap(struct thread *t, void *buf, size_t nbytes)
{
return read(t->fd, buf, nbytes);
}
static ssize_t write_wrap(struct thread *t, const void *buf, size_t nbytes)
{
return write(t->fd, buf, nbytes);
}
/******************** Empty/Fill buffer routines ****************************/
/* 0 – stream of zeros, 1 – i % 63, 2 – pipe */
enum pattern { PAT_ZERO, PAT_SEQ, PAT_PIPE };
static enum pattern pattern;
static ssize_t
fill_in_buf(struct thread *ignore, void *buf, size_t nbytes)
{
size_t i;
__u8 *p;
(void)ignore;
switch (pattern) {
case PAT_ZERO:
memset(buf, 0, nbytes);
break;
case PAT_SEQ:
for (p = buf, i = 0; i < nbytes; ++i, ++p)
*p = i % 63;
break;
case PAT_PIPE:
return fread(buf, 1, nbytes, stdin);
}
return nbytes;
}
static ssize_t
empty_out_buf(struct thread *ignore, const void *buf, size_t nbytes)
{
const __u8 *p;
__u8 expected;
ssize_t ret;
size_t len;
(void)ignore;
switch (pattern) {
case PAT_ZERO:
expected = 0;
for (p = buf, len = 0; len < nbytes; ++p, ++len)
if (*p)
goto invalid;
break;
case PAT_SEQ:
for (p = buf, len = 0; len < nbytes; ++p, ++len)
if (*p != len % 63) {
expected = len % 63;
goto invalid;
}
break;
case PAT_PIPE:
ret = fwrite(buf, nbytes, 1, stdout);
if (ret > 0)
fflush(stdout);
break;
invalid:
err(“bad OUT byte %zd, expected %02x got %02x\n”,
len, expected, *p);
for (p = buf, len = 0; len < nbytes; ++p, ++len) {
if (0 == (len % 32))
fprintf(stderr, “%4zd:”, len);
fprintf(stderr, " %02x", *p);
if (31 == (len % 32))
fprintf(stderr, “\n”);
}
fflush(stderr);
errno = EILSEQ;
return -1;
}
return len;
}
/******************** Endpoints routines ************************************/
static void handle_setup(const struct usb_ctrlrequest *setup)
{
printf(“bRequestType = %d\n”, setup->bRequestType);
printf(“bRequest = %d\n”, setup->bRequest);
printf(“wValue = %d\n”, le16_to_cpu(setup->wValue));
printf(“wIndex = %d\n”, le16_to_cpu(setup->wIndex));
printf(“wLength = %d\n”, le16_to_cpu(setup->wLength));
}
static ssize_t
ep0_consume(struct thread *ignore, const void *buf, size_t nbytes)
{
static const char *const names[] = {
[FUNCTIONFS_BIND] = “BIND”,
[FUNCTIONFS_UNBIND] = “UNBIND”,
[FUNCTIONFS_ENABLE] = “ENABLE”,
[FUNCTIONFS_DISABLE] = “DISABLE”,
[FUNCTIONFS_SETUP] = “SETUP”,
[FUNCTIONFS_SUSPEND] = “SUSPEND”,
[FUNCTIONFS_RESUME] = “RESUME”,
};
const struct usb_functionfs_event *event = buf;
size_t n;
(void)ignore;
for (n = nbytes / sizeof *event; n; --n, ++event)
switch (event->type) {
case FUNCTIONFS_BIND:
case FUNCTIONFS_UNBIND:
case FUNCTIONFS_ENABLE:
case FUNCTIONFS_DISABLE:
case FUNCTIONFS_SETUP:
case FUNCTIONFS_SUSPEND:
case FUNCTIONFS_RESUME:
printf(“Event %s\n”, names[event->type]);
if (event->type == FUNCTIONFS_SETUP)
handle_setup(&event->u.setup);
break;
default:
printf(“Event %03u (unknown)\n”, event->type);
}
return nbytes;
}
static void ep0_init(struct thread *t, bool legacy_descriptors)
{
void *legacy;
ssize_t ret;
size_t len;
if (legacy_descriptors) {
info("%s: writing descriptors\n", t->filename);
goto legacy;
}
info("%s: writing descriptors (in v2 format)\n", t->filename);
ret = write(t->fd, &descriptors, sizeof descriptors);
if (ret < 0 && errno == EINVAL) {
warn("%s: new format rejected, trying legacy\n", t->filename);
legacy:
len = descs_to_legacy(&legacy, &descriptors);
if (len) {
ret = write(t->fd, legacy, len);
free(legacy);
}
}
die_on(ret < 0, “%s: write: descriptors”, t->filename);
info("%s: writing strings\n", t->filename);
ret = write(t->fd, &strings, sizeof strings);
die_on(ret < 0, “%s: write: strings”, t->filename);
}
/******************** Main **************************************************/
int main(int argc, char **argv)
{
bool legacy_descriptors;
unsigned i;
legacy_descriptors = argc > 2 && !strcmp(argv[1], “-l”);
init_thread(threads);
ep0_init(threads, legacy_descriptors);
for (i = 1; i < sizeof threads / sizeof *threads; ++i)
init_thread(threads + i);
for (i = 1; i < sizeof threads / sizeof *threads; ++i)
start_thread(threads + i);
start_thread_helper(threads);
for (i = 1; i < sizeof threads / sizeof *threads; ++i)
join_thread(threads + i);
return 0;
}