int _rtapi_shmem_new_inst(int userkey, int instance, int module_id, unsigned long int size) {
int n, retval;
int shmem_id;
shmem_data *shmem;
struct shm_status sm;
int key = OS_KEY(userkey, instance);
/* key must be non-zero, and also cannot match the key that RTAPI uses */
if ((key == 0) || (key == OS_KEY(RTAPI_KEY, instance))) {
rtapi_print_msg(RTAPI_MSG_ERR, "RTAPI: ERROR: bad shmem key: %d\n",
key);
return -EINVAL;
}
/* get the mutex */
rtapi_mutex_get(&(rtapi_data->mutex));
/* validate module_id */
if ((module_id < 1) || (module_id > RTAPI_MAX_MODULES)) {
rtapi_mutex_give(&(rtapi_data->mutex));
rtapi_print_msg(RTAPI_MSG_ERR, "RTAPI: ERROR: bad module ID: %d\n",
module_id);
return -EINVAL;
}
if (module_array[module_id].state != MODULE_STATE) {
rtapi_print_msg(RTAPI_MSG_ERR,
"RTAPI: ERROR: not a " OUR_API " module ID: %d\n",
module_id);
rtapi_mutex_give(&(rtapi_data->mutex));
return -EINVAL;
}
/* check if a block is already open for this key */
for (n = 1; n <= RTAPI_MAX_SHMEMS; n++) {
if (shmem_array[n].key == key) {
/* found a match */
shmem_id = n;
shmem = &(shmem_array[n]);
/* is it big enough? */
if (shmem->size < size) {
rtapi_mutex_give(&(rtapi_data->mutex));
rtapi_print_msg(RTAPI_MSG_ERR,
"RTAPI: ERROR: shmem size mismatch\n");
return -EINVAL;
}
/* is this module already using it? */
if (rtapi_test_bit(module_id, shmem->bitmap)) {
rtapi_mutex_give(&(rtapi_data->mutex));
rtapi_print_msg(RTAPI_MSG_WARN,
"RTAPI: Warning: shmem already mapped\n");
return -EEXIST;
}
/* yes, has it been mapped into kernel space? */
#ifdef RTAPI
if (shmem->rtusers == 0) {
#endif
/* no, map it and save the address */
sm.key = key;
sm.size = size;
sm.flags = 0;
#ifdef ULAPI
sm.driver_fd = shmdrv_driver_fd();
#endif
retval = shmdrv_attach(&sm, &shmem_addr_array[shmem_id]);
if (retval < 0) {
rtapi_mutex_give(&(rtapi_data->mutex));
rtapi_print_msg(RTAPI_MSG_ERR,
"shmdrv attached failed key=0x%x size=%ld\n", key, size);
return retval;
}
if (shmem_addr_array[shmem_id] == NULL) {
rtapi_print_msg(RTAPI_MSG_ERR,
"RTAPI: ERROR: failed to map shmem\n");
rtapi_mutex_give(&(rtapi_data->mutex));
#ifdef ULAPI
check_memlock_limit("failed to map shmem");
#endif
return -ENOMEM;
}
#ifdef RTAPI
}
#endif
/* update usage data */
rtapi_set_bit(module_id, shmem->bitmap);
#ifdef ULAPI
shmem->ulusers++;
#else /* RTAPI */
shmem->rtusers++;
#endif /* RTAPI */
/* announce another user for this shmem */
rtapi_print_msg(RTAPI_MSG_DBG,
"RTAPI: shmem %02d opened by module %02d\n",
shmem_id, module_id);
/* done */
rtapi_mutex_give(&(rtapi_data->mutex));
return shmem_id;
}
}
/* find empty spot in shmem array */
n = 1;
while ((n <= RTAPI_MAX_SHMEMS) && (shmem_array[n].key != 0)) {
rtapi_print_msg(RTAPI_MSG_DBG, OUR_API ": shmem %d occupuied \n",n);
n++;
}
if (n > RTAPI_MAX_SHMEMS) {
/* no room */
rtapi_mutex_give(&(rtapi_data->mutex));
rtapi_print_msg(RTAPI_MSG_ERR, "RTAPI: ERROR: reached shmem limit %d\n",
n);
return -EMFILE;
}
/* we have space for the block data */
rtapi_print_msg(RTAPI_MSG_DBG, OUR_API ": using new shmem %d \n",n);
shmem_id = n;
shmem = &(shmem_array[n]);
/* get shared memory block from OS and save its address */
sm.key = key;
sm.size = size;
sm.flags = 0;
#ifdef ULAPI
sm.driver_fd = shmdrv_driver_fd();
#endif
retval = shmdrv_create(&sm);
if (retval < 0) {
rtapi_mutex_give(&(rtapi_data->mutex));
rtapi_print_msg(RTAPI_MSG_ERR,"shmdrv create failed key=0x%x size=%ld\n", key, size);
return retval;
}
retval = shmdrv_attach(&sm, &shmem_addr_array[shmem_id]);
if (retval < 0) {
rtapi_mutex_give(&(rtapi_data->mutex));
rtapi_print_msg(RTAPI_MSG_ERR,"shmdrv attached failed key=0x%x size=%ld\n", key, size);
return retval;
}
if (shmem_addr_array[shmem_id] == NULL) {
rtapi_mutex_give(&(rtapi_data->mutex));
rtapi_print_msg(RTAPI_MSG_ERR,
"RTAPI: ERROR: could not create shmem %d\n", n);
return -ENOMEM;
}
/* the block has been created, update data */
rtapi_set_bit(module_id, shmem->bitmap);
shmem->key = key;
#ifdef RTAPI
shmem->rtusers = 1;
shmem->ulusers = 0;
#else /* ULAPI */
shmem->rtusers = 0;
shmem->ulusers = 1;
#endif /* ULAPI */
shmem->size = size;
shmem->magic = SHMEM_MAGIC;
shmem->instance = instance;
rtapi_data->shmem_count++;
/* zero the first word of the shmem area */
*((long int *) (shmem_addr_array[shmem_id])) = 0;
/* announce the birth of a brand new baby shmem */
rtapi_print_msg(RTAPI_MSG_DBG,
"RTAPI: shmem %02d created by module %02d, key: %d, size: %lu\n",
shmem_id, module_id, key, size);
/* and return the ID to the proud parent */
rtapi_mutex_give(&(rtapi_data->mutex));
return shmem_id;
}
int init_module(void) {
int n;
struct shm_status sm;
int retval;
rtapi_switch = rtapi_get_handle();
// first thing: attach global_data
sm.key = OS_KEY(GLOBAL_KEY, rtapi_instance);
sm.size = 0;
sm.flags = 0;
if ((retval = shmdrv_attach(&sm, (void **)&global_data)) < 0) {
// cant use the message ringbuffer just yet
printk("RTAPI:%d ERROR: can attach global segment: %d\n",
rtapi_instance, retval);
return -EINVAL;
}
// fail immediately if the global segment isnt in shape yet
// this catches https://github.com/zultron/linuxcnc/issues/49 early
if (global_data->magic != GLOBAL_READY) {
printk("RTAPI:%d ERROR: bad global magic: 0x%x\n",
rtapi_instance,global_data->magic);
// TBD: remove once cause identified
printk("halsize=%d\n", global_data->hal_size);
printk("msgd pid=%d\n", global_data->rtapi_msgd_pid);
printk("magic=%x\n", global_data->magic);
printk("flavor=%d\n", global_data->rtapi_thread_flavor);
// fail the insmod
return -EINVAL;
}
// say hello - this now goes through the message ringbuffer
rtapi_print_msg(RTAPI_MSG_INFO, "RTAPI:%d %s %s init\n",
rtapi_instance,
rtapi_get_handle()->thread_flavor_name,
GIT_VERSION);
sm.key = OS_KEY(RTAPI_KEY, rtapi_instance);
sm.size = sizeof(rtapi_data_t);
sm.flags = 0;
if ((retval = shmdrv_create(&sm)) < 0) {
rtapi_print_msg(RTAPI_MSG_ERR,
"RTAPI:%d ERROR: can create rtapi segment: %d\n",
rtapi_instance, retval);
return -EINVAL;
}
if ((retval = shmdrv_attach(&sm, (void **)&rtapi_data)) < 0) {
rtapi_print_msg(RTAPI_MSG_ERR,
"RTAPI:%d ERROR: cant attach rtapi segment: %d\n",
rtapi_instance, retval);
return -EINVAL;
}
// make error ringbuffer accessible within RTAPI
ringbuffer_init(&global_data->rtapi_messages, &rtapi_message_buffer);
global_data->rtapi_messages.refcount += 1; // rtapi is 'attached'
// tag messages originating from RT proper
rtapi_set_logtag("rt");
/* this will take care of any threads flavor hook */
init_rtapi_data(rtapi_data);
/* check flavor and serial codes */
if (rtapi_data->thread_flavor_id != THREAD_FLAVOR_ID) {
/* mismatch - release master shared memory block */
rtapi_print_msg(RTAPI_MSG_ERR,
"RTAPI: ERROR: flavor mismatch %d vs %d\n",
rtapi_data->thread_flavor_id, THREAD_FLAVOR_ID);
sm.key = OS_KEY(RTAPI_KEY, rtapi_instance);
sm.size = sizeof(global_data_t);
sm.flags = 0;
if ((retval = shmdrv_detach(&sm)) < 0) {
rtapi_print_msg(RTAPI_MSG_ERR,
"INSTANCE:%d ERROR: shmdrv_detach() returns %d\n",
rtapi_instance, retval);
}
sm.key = OS_KEY(GLOBAL_KEY, rtapi_instance);
sm.size = sizeof(global_data_t);
sm.flags = 0;
if ((retval = shmdrv_detach(&sm)) < 0) {
rtapi_print_msg(RTAPI_MSG_ERR,
"INSTANCE:%d ERROR: shmdrv_detach() returns %d\n",
rtapi_instance, retval);
}
return -EINVAL;
}
if (rtapi_data->serial != RTAPI_SERIAL) {
/* mismatch - release master shared memory block */
rtapi_print_msg(RTAPI_MSG_ERR,
"RTAPI: ERROR: serial mismatch '%d' vs '%d'\n",
rtapi_data->serial, RTAPI_SERIAL);
return -EINVAL;
}
/* set up local pointers to global data */
module_array = rtapi_data->module_array;
task_array = rtapi_data->task_array;
shmem_array = rtapi_data->shmem_array;
/* perform local init */
for (n = 0; n <= RTAPI_MAX_TASKS; n++) {
ostask_array[n] = NULL;
}
for (n = 0; n <= RTAPI_MAX_SHMEMS; n++) {
shmem_addr_array[n] = NULL;
}
rtapi_data->timer_running = 0;
rtapi_data->timer_period = 0;
max_delay = DEFAULT_MAX_DELAY;
#ifdef RT_LINUX_USE_FPU
rt_linux_use_fpu(1);
#endif
#if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,0)
/* on SMP machines, we want to put RT code on the last CPU */
n = NR_CPUS-1;
while ( ! cpu_online(n) ) {
n--;
}
rtapi_data->rt_cpu = n;
#else
/* old kernel, the SMP hooks aren't available, so use CPU 0 */
rtapi_data->rt_cpu = 0;
#endif
#ifdef CONFIG_PROC_FS
/* set up /proc/rtapi */
if (proc_init() != 0) {
rtapi_print_msg(RTAPI_MSG_WARN,
"RTAPI: WARNING: Could not activate /proc entries\n");
proc_clean();
}
#endif
#ifdef HAVE_RTAPI_MODULE_INIT_HOOK
_rtapi_module_init_hook();
#endif
/* done */
rtapi_print_msg(RTAPI_MSG_INFO, "RTAPI:%d Init complete\n",
rtapi_instance);
return 0;
}
int shm_common_new(int key, int *size, int instance, void **shmptr, int create)
{
struct shm_status sm;
int retval;
int is_new = 0;
if (shmdrv_loaded) {
// use shmdrv kernel driver
sm.driver_fd = shmdrv_driver_fd();
sm.key = key;
sm.size = (size == NULL? 0: *size);
sm.flags = 0;
retval = shmdrv_status(&sm); // check if exists
if (retval && !create) {
// didnt exist, but just attach requested, so fail
close(sm.driver_fd);
return -ENOENT;
}
if (retval) { // didnt exist, so create
retval = shmdrv_create(&sm);
if (retval < 0) {
return retval;
}
is_new = 1;
}
// now attach
retval = shmdrv_attach(&sm, shmptr);
if (retval < 0) {
close(sm.driver_fd);
return retval;
}
// if size was passed in as 0 (attach), fill in actual size
if (size && (*size == 0))
*size = sm.size;
close(sm.driver_fd);
return is_new;
} else {
// use POSIX shared memory
int shmfd, mmap_size;
mode_t old_umask;
char segment_name[LINELEN];
if ((size == 0) || (*size == 0))
mmap_size = 0;
else
mmap_size = *size;
sprintf(segment_name, SHM_FMT, instance, key);
old_umask = umask(0); //S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
if (create && ((shmfd = shm_open(segment_name,
(O_CREAT | O_EXCL | O_RDWR),
(S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP))) > 0)) {
// initial creation
if (fchown(shmfd, getuid(),getgid()))
perror("fchown");
if (ftruncate(shmfd, mmap_size))
perror("ftruncate");
is_new = 1;
} else if((shmfd = shm_open(segment_name, O_RDWR,
(S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP))) < 0) {
// just attach, and that failed:
umask(old_umask);
return -errno;
} else { // shmfd open
if (mmap_size == 0) {
struct stat st;
if (fstat(shmfd, &st)) {
perror("fstat");
return -errno;
}
mmap_size = st.st_size;
}
}
if((*shmptr = mmap(0, mmap_size, (PROT_READ | PROT_WRITE),
MAP_SHARED, shmfd, 0)) == MAP_FAILED) {
perror("shm_common_new:mmap");
close(shmfd);
umask(old_umask);
return -errno;
}
if (size) // return actual shm size as determined in attach
*size = mmap_size;
umask(old_umask);
close(shmfd);
return is_new;
}
}