static int my_init (void) {
proc_mydev = proc_mkdir(MYDEV,0);
proc_hello = create_proc_entry(HELLO,0,proc_mydev);
proc_hello->read_proc = read_hello;
proc_hello->write_proc = write_hello;
#if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,29)
proc_hello->owner = THIS_MODULE;
#endif
hello_data=(struct proc_hello_data *)
kmalloc(sizeof(*hello_data),GFP_KERNEL);
hello_data->proc_hello_value=(char *)
kmalloc(PROC_HELLO_BUFLEN,GFP_KERNEL);
hello_data->proc_hello_wqh=(wait_queue_head_t *)
kmalloc(sizeof(wait_queue_head_t),GFP_KERNEL);
hello_data->proc_hello_wq=(wait_queue_t *)
kmalloc(sizeof(wait_queue_t),GFP_KERNEL);
// see what happens when the following line is commented out
//
init_waitqueue_head(hello_data->proc_hello_wqh);
init_wait(hello_data->proc_hello_wq);
hello_data->proc_hello_flag=0;
// module init message
printk(KERN_ALERT "2470:10.1: main initialized!\n");
return 0;
}
struct ceph_msg *ceph_msgpool_get(struct ceph_msgpool *pool, int front_len)
{
wait_queue_t wait;
struct ceph_msg *msg;
if (front_len && front_len > pool->front_len) {
pr_err("msgpool_get pool %p need front %d, pool size is %d\n",
pool, front_len, pool->front_len);
WARN_ON(1);
/* try to alloc a fresh message */
msg = ceph_msg_new(0, front_len, 0, 0, NULL);
if (!IS_ERR(msg))
return msg;
}
if (!front_len)
front_len = pool->front_len;
if (pool->blocking) {
/* mempool_t behavior; first try to alloc */
msg = ceph_msg_new(0, front_len, 0, 0, NULL);
if (!IS_ERR(msg))
return msg;
}
while (1) {
spin_lock(&pool->lock);
if (likely(pool->num)) {
msg = list_entry(pool->msgs.next, struct ceph_msg,
list_head);
list_del_init(&msg->list_head);
pool->num--;
dout("msgpool_get %p got %p, now %d/%d\n", pool, msg,
pool->num, pool->min);
spin_unlock(&pool->lock);
return msg;
}
pr_err("msgpool_get %p now %d/%d, %s\n", pool, pool->num,
pool->min, pool->blocking ? "waiting" : "may fail");
spin_unlock(&pool->lock);
if (!pool->blocking) {
WARN_ON(1);
/* maybe we can allocate it now? */
msg = ceph_msg_new(0, front_len, 0, 0, NULL);
if (!IS_ERR(msg))
return msg;
pr_err("msgpool_get %p empty + alloc failed\n", pool);
return ERR_PTR(-ENOMEM);
}
init_wait(&wait);
prepare_to_wait(&pool->wait, &wait, TASK_UNINTERRUPTIBLE);
schedule();
finish_wait(&pool->wait, &wait);
}
/**
* mempool_alloc - allocate an element from a specific memory pool
* @pool: pointer to the memory pool which was allocated via
* mempool_create().
* @gfp_mask: the usual allocation bitmask.
*
* this function only sleeps if the alloc_fn() function sleeps or
* returns NULL. Note that due to preallocation, this function
* *never* fails when called from process contexts. (it might
* fail if called from an IRQ context.)
*/
void * mempool_alloc(mempool_t *pool, gfp_t gfp_mask)
{
void *element;
unsigned long flags;
wait_queue_t wait;
gfp_t gfp_temp;
#ifdef CONFIG_KRG_EPM
struct task_struct *krg_cur;
#endif
might_sleep_if(gfp_mask & __GFP_WAIT);
gfp_mask |= __GFP_NOMEMALLOC; /* don't allocate emergency reserves */
gfp_mask |= __GFP_NORETRY; /* don't loop in __alloc_pages */
gfp_mask |= __GFP_NOWARN; /* failures are OK */
gfp_temp = gfp_mask & ~(__GFP_WAIT|__GFP_IO);
repeat_alloc:
element = pool->alloc(gfp_temp, pool->pool_data);
if (likely(element != NULL))
return element;
spin_lock_irqsave(&pool->lock, flags);
if (likely(pool->curr_nr)) {
element = remove_element(pool);
spin_unlock_irqrestore(&pool->lock, flags);
return element;
}
spin_unlock_irqrestore(&pool->lock, flags);
/* We must not sleep in the GFP_ATOMIC case */
if (!(gfp_mask & __GFP_WAIT))
return NULL;
#ifdef CONFIG_KRG_EPM
krg_current_save(krg_cur);
#endif
/* Now start performing page reclaim */
gfp_temp = gfp_mask;
init_wait(&wait);
prepare_to_wait(&pool->wait, &wait, TASK_UNINTERRUPTIBLE);
smp_mb();
if (!pool->curr_nr) {
/*
* FIXME: this should be io_schedule(). The timeout is there
* as a workaround for some DM problems in 2.6.18.
*/
io_schedule_timeout(5*HZ);
}
finish_wait(&pool->wait, &wait);
#ifdef CONFIG_KRG_EPM
krg_current_restore(krg_cur);
#endif
goto repeat_alloc;
}
/**
* mempool_alloc - allocate an element from a specific memory pool
* @pool: pointer to the memory pool which was allocated via
* mempool_create().
* @gfp_mask: the usual allocation bitmask.
*
* this function only sleeps if the alloc_fn function sleeps or
* returns NULL. Note that due to preallocation, this function
* *never* fails when called from process contexts. (it might
* fail if called from an IRQ context.)
*/
void * mempool_alloc(mempool_t *pool, gfp_t gfp_mask)
{
void *element;
unsigned long flags;
wait_queue_t wait;
gfp_t gfp_temp;
might_sleep_if(gfp_mask & __GFP_WAIT);
gfp_mask |= __GFP_NOMEMALLOC; /* don't allocate emergency reserves */
gfp_mask |= __GFP_NORETRY; /* don't loop in __alloc_pages */
gfp_mask |= __GFP_NOWARN; /* failures are OK */
gfp_temp = gfp_mask & ~(__GFP_WAIT|__GFP_IO);
repeat_alloc:
element = pool->alloc(gfp_temp, pool->pool_data);
if (likely(element != NULL))
return element;
spin_lock_irqsave(&pool->lock, flags);
if (likely(pool->curr_nr)) {
element = remove_element(pool);
spin_unlock_irqrestore(&pool->lock, flags);
return element;
}
spin_unlock_irqrestore(&pool->lock, flags);
/* We must not sleep in the GFP_ATOMIC case */
if (!(gfp_mask & __GFP_WAIT))
return NULL;
/* Now start performing page reclaim */
gfp_temp = gfp_mask;
init_wait(&wait);
prepare_to_wait(&pool->wait, &wait, TASK_UNINTERRUPTIBLE);
smp_mb();
if (!pool->curr_nr)
io_schedule();
finish_wait(&pool->wait, &wait);
goto repeat_alloc;
}
void pin_kill(struct fs_pin *p)
{
wait_queue_entry_t wait;
if (!p) {
rcu_read_unlock();
return;
}
init_wait(&wait);
spin_lock_irq(&p->wait.lock);
if (likely(!p->done)) {
p->done = -1;
spin_unlock_irq(&p->wait.lock);
rcu_read_unlock();
p->kill(p);
return;
}
if (p->done > 0) {
spin_unlock_irq(&p->wait.lock);
rcu_read_unlock();
return;
}
__add_wait_queue(&p->wait, &wait);
while (1) {
set_current_state(TASK_UNINTERRUPTIBLE);
spin_unlock_irq(&p->wait.lock);
rcu_read_unlock();
schedule();
rcu_read_lock();
if (likely(list_empty(&wait.entry)))
break;
/* OK, we know p couldn't have been freed yet */
spin_lock_irq(&p->wait.lock);
if (p->done > 0) {
spin_unlock_irq(&p->wait.lock);
break;
}
}
rcu_read_unlock();
}
NDAS_SAL_API
int
sal_event_wait(sal_event event, sal_tick timeout)
{
struct _sal_event *sevent = (struct _sal_event*) event;
long timeleft = timeout;
int ret = SAL_SYNC_OK;
wait_queue_t wait;
#if LINUX_VERSION_25_ABOVE
if(in_interrupt() || in_atomic() || irqs_disabled()) {
#else
if(in_interrupt()) {
#endif
#ifdef DEBUG
*(char *)0 = 0;
#endif
printk(KERN_ERR "Tried wait in interrupt context.\n");
return SAL_SYNC_ERR;
}
#if LINUX_VERSION_25_ABOVE
// Initialze the wait.
init_wait(&wait);
#else
// Initialize the wait
init_waitqueue_entry(&wait, current);
// Add the wait to the queue
add_wait_queue(&sevent->queue, &wait);
#endif
for(;;)
{
#if LINUX_VERSION_25_ABOVE
// Add the wait to the queue if the wait is not added.
// Set current process state to TASK_INTERRUPTIBLE
prepare_to_wait(&sevent->queue, &wait, TASK_INTERRUPTIBLE);
#else
// Set current process state to TASK_INTERRUPTIBLE
set_current_state(TASK_INTERRUPTIBLE);
#endif
// See if the state is set.
if(atomic_read(&sevent->state))
break;
if(!signal_pending(current)) {
if( timeout == SAL_SYNC_FOREVER) {
schedule();
continue;
}
else
{
timeleft = schedule_timeout(timeleft);
// See if timeout.
if(!timeleft) {
ret = SAL_SYNC_TIMEOUT;
break;
}
continue;
}
}
ret = SAL_SYNC_INTERRUPTED;
break;
}
#if LINUX_VERSION_25_ABOVE
// Set current process state to TASK_RUNNING
// Remove the wait from the queue.
finish_wait(&sevent->queue, &wait);
#else
// Set current process state to TASK_RUNNING
current->state = TASK_RUNNING;
// Remove the wait from the queue.
remove_wait_queue(&sevent->queue, &wait);
#endif
return ret;
}
EXPORT_SYMBOL(sal_event_wait);
NDAS_SAL_API
void
sal_event_set(sal_event event)
{
struct _sal_event *sevent = (struct _sal_event*) event;
atomic_set(&sevent->state, 1);
wake_up_interruptible(&sevent->queue);
}
EXPORT_SYMBOL(sal_event_set);
NDAS_SAL_API
void
sal_event_reset(sal_event event)
{
struct _sal_event *sevent = (struct _sal_event*) event;
atomic_set(&sevent->state, 0);
}
EXPORT_SYMBOL(sal_event_reset);
NDAS_SAL_API
void
sal_atomic_inc(sal_atomic *v)
{
/* NDAS SAL uses same struct for atomic structure */
atomic_inc((atomic_t*)v);
}
/**
* mempool_alloc - allocate an element from a specific memory pool
* @pool: pointer to the memory pool which was allocated via
* mempool_create().
* @gfp_mask: the usual allocation bitmask.
*
* this function only sleeps if the alloc_fn() function sleeps or
* returns NULL. Note that due to preallocation, this function
* *never* fails when called from process contexts. (it might
* fail if called from an IRQ context.)
* Note: using __GFP_ZERO is not supported.
*/
void * mempool_alloc(mempool_t *pool, gfp_t gfp_mask)
{
void *element;
unsigned long flags;
wait_queue_t wait;
gfp_t gfp_temp;
VM_WARN_ON_ONCE(gfp_mask & __GFP_ZERO);
might_sleep_if(gfp_mask & __GFP_WAIT);
gfp_mask |= __GFP_NOMEMALLOC; /* don't allocate emergency reserves */
gfp_mask |= __GFP_NORETRY; /* don't loop in __alloc_pages */
gfp_mask |= __GFP_NOWARN; /* failures are OK */
gfp_temp = gfp_mask & ~(__GFP_WAIT|__GFP_IO);
repeat_alloc:
element = pool->alloc(gfp_temp, pool->pool_data);
if (likely(element != NULL))
return element;
spin_lock_irqsave(&pool->lock, flags);
if (likely(pool->curr_nr)) {
element = remove_element(pool);
spin_unlock_irqrestore(&pool->lock, flags);
/* paired with rmb in mempool_free(), read comment there */
smp_wmb();
/*
* Update the allocation stack trace as this is more useful
* for debugging.
*/
kmemleak_update_trace(element);
return element;
}
/*
* We use gfp mask w/o __GFP_WAIT or IO for the first round. If
* alloc failed with that and @pool was empty, retry immediately.
*/
if (gfp_temp != gfp_mask) {
spin_unlock_irqrestore(&pool->lock, flags);
gfp_temp = gfp_mask;
goto repeat_alloc;
}
/* We must not sleep if !__GFP_WAIT */
if (!(gfp_mask & __GFP_WAIT)) {
spin_unlock_irqrestore(&pool->lock, flags);
return NULL;
}
/* Let's wait for someone else to return an element to @pool */
init_wait(&wait);
prepare_to_wait(&pool->wait, &wait, TASK_UNINTERRUPTIBLE);
spin_unlock_irqrestore(&pool->lock, flags);
/*
* FIXME: this should be io_schedule(). The timeout is there as a
* workaround for some DM problems in 2.6.18.
*/
io_schedule_timeout(5*HZ);
finish_wait(&pool->wait, &wait);
goto repeat_alloc;
}
/* _VMKLNX_CODECHECK_: mempool_alloc */
void * mempool_alloc(mempool_t *pool, gfp_t gfp_mask)
{
void *element;
unsigned long flags;
wait_queue_t wait;
gfp_t gfp_temp;
#if defined(__VMKLNX__)
VMK_ASSERT(vmk_PreemptionIsEnabled() == VMK_FALSE);
#endif
might_sleep_if(gfp_mask & __GFP_WAIT);
gfp_mask |= __GFP_NOMEMALLOC; /* don't allocate emergency reserves */
gfp_mask |= __GFP_NORETRY; /* don't loop in __alloc_pages */
gfp_mask |= __GFP_NOWARN; /* failures are OK */
gfp_temp = gfp_mask & ~(__GFP_WAIT|__GFP_IO);
#if defined(__VMKLNX__) && defined(VMX86_DEBUG)
if (gfp_mask & __GFP_WAIT) {
vmk_WorldAssertIsSafeToBlock();
}
#endif /* defined(__VMKLNX__) */
repeat_alloc:
#if defined(__VMKLNX__)
VMKAPI_MODULE_CALL(pool->module_id, element, pool->alloc,
gfp_temp, pool->pool_data);
#else /* !defined(__VMKLNX__) */
element = pool->alloc(gfp_temp, pool->pool_data);
#endif /* defined(__VMKLNX__) */
if (likely(element != NULL))
return element;
spin_lock_irqsave(&pool->lock, flags);
if (likely(pool->curr_nr)) {
element = remove_element(pool);
spin_unlock_irqrestore(&pool->lock, flags);
return element;
}
spin_unlock_irqrestore(&pool->lock, flags);
/* We must not sleep in the GFP_ATOMIC case */
if (!(gfp_mask & __GFP_WAIT))
return NULL;
/* Now start performing page reclaim */
gfp_temp = gfp_mask;
init_wait(&wait);
prepare_to_wait(&pool->wait, &wait, TASK_UNINTERRUPTIBLE);
smp_mb();
if (!pool->curr_nr) {
/*
* FIXME: this should be io_schedule(). The timeout is there
* as a workaround for some DM problems in 2.6.18.
*/
#if defined(__VMKLNX__)
schedule_timeout(5*HZ);
#else /* !defined(__VMKLNX__) */
io_schedule_timeout(5*HZ);
#endif /* defined(__VMKLNX__) */
}
finish_wait(&pool->wait, &wait);
goto repeat_alloc;
}
