static void *alloc_block(struct k_mem_pool *p, int l, size_t lsz)
{
sys_dnode_t *block;
int key = irq_lock();
block = sys_dlist_get(&p->levels[l].free_list);
if (block) {
clear_free_bit(p, l, block_num(p, block, lsz));
}
irq_unlock(key);
return block;
}
int k_pipe_get(struct k_pipe *pipe, void *data, size_t bytes_to_read,
size_t *bytes_read, size_t min_xfer, s32_t timeout)
{
struct k_thread *writer;
struct k_pipe_desc *desc;
sys_dlist_t xfer_list;
unsigned int key;
size_t num_bytes_read = 0;
size_t bytes_copied;
__ASSERT(min_xfer <= bytes_to_read, "");
__ASSERT(bytes_read != NULL, "");
key = irq_lock();
/*
* Create a list of "working readers" into which the data will be
* directly copied.
*/
if (!_pipe_xfer_prepare(&xfer_list, &writer, &pipe->wait_q.writers,
pipe->bytes_used, bytes_to_read,
min_xfer, timeout)) {
irq_unlock(key);
*bytes_read = 0;
return -EIO;
}
_sched_lock();
irq_unlock(key);
num_bytes_read = _pipe_buffer_get(pipe, data, bytes_to_read);
/*
* 1. 'xfer_list' currently contains a list of writer threads that can
* have their write requests fulfilled by the current call.
* 2. 'writer' if not NULL points to a thread on the writer wait_q
* that can post some of its requested data.
* 3. Data will be copied from each writer's buffer to either the
* reader's buffer and/or to the pipe's circular buffer.
* 4. Interrupts are unlocked but the scheduler is locked to allow
* ticks to be delivered but no scheduling to occur
* 5. If 'writer' times out while we are copying data, not only do we
* still have a pointer to it, but it can not execute until this
* call is complete so it is still safe to copy data from it.
*/
struct k_thread *thread = (struct k_thread *)
sys_dlist_get(&xfer_list);
while (thread && (num_bytes_read < bytes_to_read)) {
desc = (struct k_pipe_desc *)thread->base.swap_data;
bytes_copied = _pipe_xfer(data + num_bytes_read,
bytes_to_read - num_bytes_read,
desc->buffer, desc->bytes_to_xfer);
num_bytes_read += bytes_copied;
desc->buffer += bytes_copied;
desc->bytes_to_xfer -= bytes_copied;
/*
* It is expected that the write request will be satisfied.
* However, if the read request was satisfied before the
* write request was satisfied, then the write request must
* finish later when writing to the pipe's circular buffer.
*/
if (num_bytes_read == bytes_to_read) {
break;
}
_pipe_thread_ready(thread);
thread = (struct k_thread *)sys_dlist_get(&xfer_list);
}
if (writer && (num_bytes_read < bytes_to_read)) {
desc = (struct k_pipe_desc *)writer->base.swap_data;
bytes_copied = _pipe_xfer(data + num_bytes_read,
bytes_to_read - num_bytes_read,
desc->buffer, desc->bytes_to_xfer);
num_bytes_read += bytes_copied;
desc->buffer += bytes_copied;
desc->bytes_to_xfer -= bytes_copied;
}
/*
* Copy as much data as possible from the writers (if any)
* into the pipe's circular buffer.
*/
while (thread) {
desc = (struct k_pipe_desc *)thread->base.swap_data;
bytes_copied = _pipe_buffer_put(pipe, desc->buffer,
desc->bytes_to_xfer);
desc->buffer += bytes_copied;
desc->bytes_to_xfer -= bytes_copied;
/* Write request has been satsified */
_pipe_thread_ready(thread);
thread = (struct k_thread *)sys_dlist_get(&xfer_list);
}
if (writer) {
desc = (struct k_pipe_desc *)writer->base.swap_data;
bytes_copied = _pipe_buffer_put(pipe, desc->buffer,
desc->bytes_to_xfer);
desc->buffer += bytes_copied;
desc->bytes_to_xfer -= bytes_copied;
}
if (num_bytes_read == bytes_to_read) {
k_sched_unlock();
*bytes_read = num_bytes_read;
return 0;
}
/* Not all data was read. */
struct k_pipe_desc pipe_desc;
pipe_desc.buffer = data + num_bytes_read;
pipe_desc.bytes_to_xfer = bytes_to_read - num_bytes_read;
if (timeout != K_NO_WAIT) {
_current->base.swap_data = &pipe_desc;
key = irq_lock();
_sched_unlock_no_reschedule();
_pend_current_thread(&pipe->wait_q.readers, timeout);
_Swap(key);
} else {
k_sched_unlock();
}
*bytes_read = bytes_to_read - pipe_desc.bytes_to_xfer;
return _pipe_return_code(min_xfer, pipe_desc.bytes_to_xfer,
bytes_to_read);
}
/**
* @brief Internal API used to send data to a pipe
*/
int _k_pipe_put_internal(struct k_pipe *pipe, struct k_pipe_async *async_desc,
unsigned char *data, size_t bytes_to_write,
size_t *bytes_written, size_t min_xfer,
s32_t timeout)
{
struct k_thread *reader;
struct k_pipe_desc *desc;
sys_dlist_t xfer_list;
unsigned int key;
size_t num_bytes_written = 0;
size_t bytes_copied;
#if (CONFIG_NUM_PIPE_ASYNC_MSGS == 0)
ARG_UNUSED(async_desc);
#endif
key = irq_lock();
/*
* Create a list of "working readers" into which the data will be
* directly copied.
*/
if (!_pipe_xfer_prepare(&xfer_list, &reader, &pipe->wait_q.readers,
pipe->size - pipe->bytes_used, bytes_to_write,
min_xfer, timeout)) {
irq_unlock(key);
*bytes_written = 0;
return -EIO;
}
_sched_lock();
irq_unlock(key);
/*
* 1. 'xfer_list' currently contains a list of reader threads that can
* have their read requests fulfilled by the current call.
* 2. 'reader' if not NULL points to a thread on the reader wait_q
* that can get some of its requested data.
* 3. Interrupts are unlocked but the scheduler is locked to allow
* ticks to be delivered but no scheduling to occur
* 4. If 'reader' times out while we are copying data, not only do we
* still have a pointer to it, but it can not execute until this call
* is complete so it is still safe to copy data to it.
*/
struct k_thread *thread = (struct k_thread *)
sys_dlist_get(&xfer_list);
while (thread) {
desc = (struct k_pipe_desc *)thread->base.swap_data;
bytes_copied = _pipe_xfer(desc->buffer, desc->bytes_to_xfer,
data + num_bytes_written,
bytes_to_write - num_bytes_written);
num_bytes_written += bytes_copied;
desc->buffer += bytes_copied;
desc->bytes_to_xfer -= bytes_copied;
/* The thread's read request has been satisfied. Ready it. */
key = irq_lock();
_ready_thread(thread);
irq_unlock(key);
thread = (struct k_thread *)sys_dlist_get(&xfer_list);
}
/*
* Copy any data to the reader that we left on the wait_q.
* It is possible no data will be copied.
*/
if (reader) {
desc = (struct k_pipe_desc *)reader->base.swap_data;
bytes_copied = _pipe_xfer(desc->buffer, desc->bytes_to_xfer,
data + num_bytes_written,
bytes_to_write - num_bytes_written);
num_bytes_written += bytes_copied;
desc->buffer += bytes_copied;
desc->bytes_to_xfer -= bytes_copied;
}
/*
* As much data as possible has been directly copied to any waiting
* readers. Add as much as possible to the pipe's circular buffer.
*/
num_bytes_written +=
_pipe_buffer_put(pipe, data + num_bytes_written,
bytes_to_write - num_bytes_written);
if (num_bytes_written == bytes_to_write) {
*bytes_written = num_bytes_written;
#if (CONFIG_NUM_PIPE_ASYNC_MSGS > 0)
if (async_desc != NULL) {
_pipe_async_finish(async_desc);
}
#endif
k_sched_unlock();
return 0;
}
/* Not all data was copied. */
#if (CONFIG_NUM_PIPE_ASYNC_MSGS > 0)
if (async_desc != NULL) {
/*
* Lock interrupts and unlock the scheduler before
* manipulating the writers wait_q.
*/
key = irq_lock();
_sched_unlock_no_reschedule();
_pend_thread((struct k_thread *) &async_desc->thread,
&pipe->wait_q.writers, K_FOREVER);
_reschedule_threads(key);
return 0;
}
#endif
struct k_pipe_desc pipe_desc;
pipe_desc.buffer = data + num_bytes_written;
pipe_desc.bytes_to_xfer = bytes_to_write - num_bytes_written;
if (timeout != K_NO_WAIT) {
_current->base.swap_data = &pipe_desc;
/*
* Lock interrupts and unlock the scheduler before
* manipulating the writers wait_q.
*/
key = irq_lock();
_sched_unlock_no_reschedule();
_pend_current_thread(&pipe->wait_q.writers, timeout);
_Swap(key);
} else {
k_sched_unlock();
}
*bytes_written = bytes_to_write - pipe_desc.bytes_to_xfer;
return _pipe_return_code(min_xfer, pipe_desc.bytes_to_xfer,
bytes_to_write);
}
