Beispiel #1
0
static int
do_get_write_access(handle_t *handle, struct journal_head *jh,
			int force_copy)
{
	struct buffer_head *bh;
	transaction_t *transaction;
	journal_t *journal;
	int error;
	char *frozen_buffer = NULL;
	int need_copy = 0;

	if (is_handle_aborted(handle))
		return -EROFS;

	transaction = handle->h_transaction;
	journal = transaction->t_journal;

	jbd_debug(5, "journal_head %p, force_copy %d\n", jh, force_copy);

	JBUFFER_TRACE(jh, "entry");
repeat:
	bh = jh2bh(jh);

	

	lock_buffer(bh);
	jbd_lock_bh_state(bh);


	if (buffer_dirty(bh)) {
		if (jh->b_transaction) {
			J_ASSERT_JH(jh,
				jh->b_transaction == transaction ||
				jh->b_transaction ==
					journal->j_committing_transaction);
			if (jh->b_next_transaction)
				J_ASSERT_JH(jh, jh->b_next_transaction ==
							transaction);
			warn_dirty_buffer(bh);
		}
		JBUFFER_TRACE(jh, "Journalling dirty buffer");
		clear_buffer_dirty(bh);
		set_buffer_jbddirty(bh);
	}

	unlock_buffer(bh);

	error = -EROFS;
	if (is_handle_aborted(handle)) {
		jbd_unlock_bh_state(bh);
		goto out;
	}
	error = 0;

	if (jh->b_transaction == transaction ||
	    jh->b_next_transaction == transaction)
		goto done;

       jh->b_modified = 0;

	if (jh->b_frozen_data) {
		JBUFFER_TRACE(jh, "has frozen data");
		J_ASSERT_JH(jh, jh->b_next_transaction == NULL);
		jh->b_next_transaction = transaction;
		goto done;
	}

	

	if (jh->b_transaction && jh->b_transaction != transaction) {
		JBUFFER_TRACE(jh, "owned by older transaction");
		J_ASSERT_JH(jh, jh->b_next_transaction == NULL);
		J_ASSERT_JH(jh, jh->b_transaction ==
					journal->j_committing_transaction);


		if (jh->b_jlist == BJ_Shadow) {
			DEFINE_WAIT_BIT(wait, &bh->b_state, BH_Unshadow);
			wait_queue_head_t *wqh;

			wqh = bit_waitqueue(&bh->b_state, BH_Unshadow);

			JBUFFER_TRACE(jh, "on shadow: sleep");
			jbd_unlock_bh_state(bh);
			
			for ( ; ; ) {
				prepare_to_wait(wqh, &wait.wait,
						TASK_UNINTERRUPTIBLE);
				if (jh->b_jlist != BJ_Shadow)
					break;
				schedule();
			}
			finish_wait(wqh, &wait.wait);
			goto repeat;
		}


		if (jh->b_jlist != BJ_Forget || force_copy) {
			JBUFFER_TRACE(jh, "generate frozen data");
			if (!frozen_buffer) {
				JBUFFER_TRACE(jh, "allocate memory for buffer");
				jbd_unlock_bh_state(bh);
				frozen_buffer =
					jbd2_alloc(jh2bh(jh)->b_size,
							 GFP_NOFS);
				if (!frozen_buffer) {
					printk(KERN_EMERG
					       "%s: OOM for frozen_buffer\n",
					       __func__);
					JBUFFER_TRACE(jh, "oom!");
					error = -ENOMEM;
					jbd_lock_bh_state(bh);
					goto done;
				}
				goto repeat;
			}
			jh->b_frozen_data = frozen_buffer;
			frozen_buffer = NULL;
			need_copy = 1;
		}
		jh->b_next_transaction = transaction;
	}


	/*
	 * Finally, if the buffer is not journaled right now, we need to make
	 * sure it doesn't get written to disk before the caller actually
	 * commits the new data
	 */
	if (!jh->b_transaction) {
		JBUFFER_TRACE(jh, "no transaction");
		J_ASSERT_JH(jh, !jh->b_next_transaction);
		JBUFFER_TRACE(jh, "file as BJ_Reserved");
		spin_lock(&journal->j_list_lock);
		__jbd2_journal_file_buffer(jh, transaction, BJ_Reserved);
		spin_unlock(&journal->j_list_lock);
	}

done:
	if (need_copy) {
		struct page *page;
		int offset;
		char *source;

		J_EXPECT_JH(jh, buffer_uptodate(jh2bh(jh)),
			    "Possible IO failure.\n");
		page = jh2bh(jh)->b_page;
		offset = offset_in_page(jh2bh(jh)->b_data);
		source = kmap_atomic(page);
		
		jbd2_buffer_frozen_trigger(jh, source + offset,
					   jh->b_triggers);
		memcpy(jh->b_frozen_data, source+offset, jh2bh(jh)->b_size);
		kunmap_atomic(source);

		jh->b_frozen_triggers = jh->b_triggers;
	}
	jbd_unlock_bh_state(bh);

	jbd2_journal_cancel_revoke(handle, jh);

out:
	if (unlikely(frozen_buffer))	
		jbd2_free(frozen_buffer, bh->b_size);

	JBUFFER_TRACE(jh, "exit");
	return error;
}
Beispiel #2
0
ssize_t pipe_write(struct file *filp, const char __user *buff,
		   size_t count, loff_t *f_pos)
{
	int retval = 0;
	struct pipe_dev *dev = filp->private_data;

	PDEBUG("%s() is invoked\n", __FUNCTION__);

	if (mutex_lock_interruptible(&dev->mutex))
		return -ERESTARTSYS;

	while (dev->buff_len) {
		DEFINE_WAIT(wait);

		mutex_unlock(&dev->mutex);
		if (filp->f_flags & O_NONBLOCK)
			return -EAGAIN;

		PDEBUG("process %d(%s) is going to sleep\n",
		       current->pid, current->comm);

		prepare_to_wait(&dev->wr_queue, &wait, TASK_INTERRUPTIBLE);
		if (dev->buff_len)
			schedule();
		finish_wait(&dev->wr_queue, &wait);

		if (signal_pending(current))
			return -ERESTARTSYS;

		if (mutex_lock_interruptible(&dev->mutex))
			return -ERESTARTSYS;
	}

	if (count > BUFF_SIZE - *f_pos)
		count = BUFF_SIZE - *f_pos;

	if (copy_from_user(dev->buff + *f_pos, buff, count)) {
		PDEBUG("write: copy to user error!\n");
		retval = -EFAULT;
		goto copy_error;
	}

	PDEBUG("write: f_pos=%lld, count=%lu, buff_len=%d\n",
	       *f_pos, count, dev->buff_len);

	// we have successfully write something in the buff
	if (count > 0) {
		dev->buff_len = count;
		*f_pos = 0;

		PDEBUG("write: process %d(%s) awakening the readers...\n",
		       current->pid, current->comm);
		wake_up_interruptible(&dev->rd_queue);
	}

	retval = count;

copy_error:
	mutex_unlock(&dev->mutex);
	return retval;
}
int tty_port_block_til_ready(struct tty_port *port,
				struct tty_struct *tty, struct file *filp)
{
	int do_clocal = 0, retval;
	unsigned long flags;
	DEFINE_WAIT(wait);

	/* block if port is in the process of being closed */
	if (tty_hung_up_p(filp) || port->flags & ASYNC_CLOSING) {
		wait_event_interruptible_tty(tty, port->close_wait,
				!(port->flags & ASYNC_CLOSING));
		if (port->flags & ASYNC_HUP_NOTIFY)
			return -EAGAIN;
		else
			return -ERESTARTSYS;
	}

	/* if non-blocking mode is set we can pass directly to open unless
	   the port has just hung up or is in another error state */
	if (tty->flags & (1 << TTY_IO_ERROR)) {
		port->flags |= ASYNC_NORMAL_ACTIVE;
		return 0;
	}
	if (filp->f_flags & O_NONBLOCK) {
		/* Indicate we are open */
		if (tty->termios.c_cflag & CBAUD)
			tty_port_raise_dtr_rts(port);
		port->flags |= ASYNC_NORMAL_ACTIVE;
		return 0;
	}

	if (C_CLOCAL(tty))
		do_clocal = 1;

	/* Block waiting until we can proceed. We may need to wait for the
	   carrier, but we must also wait for any close that is in progress
	   before the next open may complete */

	retval = 0;

	/* The port lock protects the port counts */
	spin_lock_irqsave(&port->lock, flags);
	if (!tty_hung_up_p(filp))
		port->count--;
	port->blocked_open++;
	spin_unlock_irqrestore(&port->lock, flags);

	while (1) {
		/* Indicate we are open */
		if (C_BAUD(tty) && test_bit(ASYNCB_INITIALIZED, &port->flags))
			tty_port_raise_dtr_rts(port);

		prepare_to_wait(&port->open_wait, &wait, TASK_INTERRUPTIBLE);
		/* Check for a hangup or uninitialised port.
							Return accordingly */
		if (tty_hung_up_p(filp) || !(port->flags & ASYNC_INITIALIZED)) {
			if (port->flags & ASYNC_HUP_NOTIFY)
				retval = -EAGAIN;
			else
				retval = -ERESTARTSYS;
			break;
		}
		/*
		 * Probe the carrier. For devices with no carrier detect
		 * tty_port_carrier_raised will always return true.
		 * Never ask drivers if CLOCAL is set, this causes troubles
		 * on some hardware.
		 */
		if (!(port->flags & ASYNC_CLOSING) &&
				(do_clocal || tty_port_carrier_raised(port)))
			break;
		if (signal_pending(current)) {
			retval = -ERESTARTSYS;
			break;
		}
		tty_unlock(tty);
		schedule();
		tty_lock(tty);
	}
	finish_wait(&port->open_wait, &wait);

	/* Update counts. A parallel hangup will have set count to zero and
	   we must not mess that up further */
	spin_lock_irqsave(&port->lock, flags);
	if (!tty_hung_up_p(filp))
		port->count++;
	port->blocked_open--;
	if (retval == 0)
		port->flags |= ASYNC_NORMAL_ACTIVE;
	spin_unlock_irqrestore(&port->lock, flags);
	return retval;
}
/*
 * journal_commit_transaction
 *
 * The primary function for committing a transaction to the log.  This
 * function is called by the journal thread to begin a complete commit.
 */
void journal_commit_transaction(journal_t *journal)
{
	transaction_t *commit_transaction;
	struct journal_head *jh, *new_jh, *descriptor;
	struct buffer_head **wbuf = journal->j_wbuf;
	int bufs;
	int flags;
	int err;
	unsigned long blocknr;
	char *tagp = NULL;
	journal_header_t *header;
	journal_block_tag_t *tag = NULL;
	int space_left = 0;
	int first_tag = 0;
	int tag_flag;
	int i;

	/*
	 * First job: lock down the current transaction and wait for
	 * all outstanding updates to complete.
	 */

#ifdef COMMIT_STATS
	spin_lock(&journal->j_list_lock);
	summarise_journal_usage(journal);
	spin_unlock(&journal->j_list_lock);
#endif

	/* Do we need to erase the effects of a prior journal_flush? */
	if (journal->j_flags & JFS_FLUSHED) {
		jbd_debug(3, "super block updated\n");
		journal_update_superblock(journal, 1);
	} else {
		jbd_debug(3, "superblock not updated\n");
	}

	J_ASSERT(journal->j_running_transaction != NULL);
	J_ASSERT(journal->j_committing_transaction == NULL);

	commit_transaction = journal->j_running_transaction;
	J_ASSERT(commit_transaction->t_state == T_RUNNING);

	jbd_debug(1, "JBD: starting commit of transaction %d\n",
			commit_transaction->t_tid);

	spin_lock(&journal->j_state_lock);
	commit_transaction->t_state = T_LOCKED;

	spin_lock(&commit_transaction->t_handle_lock);
	while (commit_transaction->t_updates) {
		DEFINE_WAIT(wait);

		prepare_to_wait(&journal->j_wait_updates, &wait,
					TASK_UNINTERRUPTIBLE);
		if (commit_transaction->t_updates) {
			spin_unlock(&commit_transaction->t_handle_lock);
			spin_unlock(&journal->j_state_lock);
			schedule();
			spin_lock(&journal->j_state_lock);
			spin_lock(&commit_transaction->t_handle_lock);
		}
		finish_wait(&journal->j_wait_updates, &wait);
	}
	spin_unlock(&commit_transaction->t_handle_lock);

	J_ASSERT (commit_transaction->t_outstanding_credits <=
			journal->j_max_transaction_buffers);

	/*
	 * First thing we are allowed to do is to discard any remaining
	 * BJ_Reserved buffers.  Note, it is _not_ permissible to assume
	 * that there are no such buffers: if a large filesystem
	 * operation like a truncate needs to split itself over multiple
	 * transactions, then it may try to do a journal_restart() while
	 * there are still BJ_Reserved buffers outstanding.  These must
	 * be released cleanly from the current transaction.
	 *
	 * In this case, the filesystem must still reserve write access
	 * again before modifying the buffer in the new transaction, but
	 * we do not require it to remember exactly which old buffers it
	 * has reserved.  This is consistent with the existing behaviour
	 * that multiple journal_get_write_access() calls to the same
	 * buffer are perfectly permissable.
	 */
	while (commit_transaction->t_reserved_list) {
		jh = commit_transaction->t_reserved_list;
		JBUFFER_TRACE(jh, "reserved, unused: refile");
		/*
		 * A journal_get_undo_access()+journal_release_buffer() may
		 * leave undo-committed data.
		 */
		if (jh->b_committed_data) {
			struct buffer_head *bh = jh2bh(jh);

			jbd_lock_bh_state(bh);
			jbd_free(jh->b_committed_data, bh->b_size);
			jh->b_committed_data = NULL;
			jbd_unlock_bh_state(bh);
		}
		journal_refile_buffer(journal, jh);
	}

	/*
	 * Now try to drop any written-back buffers from the journal's
	 * checkpoint lists.  We do this *before* commit because it potentially
	 * frees some memory
	 */
	spin_lock(&journal->j_list_lock);
	__journal_clean_checkpoint_list(journal);
	spin_unlock(&journal->j_list_lock);

	jbd_debug (3, "JBD: commit phase 1\n");

	/*
	 * Switch to a new revoke table.
	 */
	journal_switch_revoke_table(journal);

	commit_transaction->t_state = T_FLUSH;
	journal->j_committing_transaction = commit_transaction;
	journal->j_running_transaction = NULL;
	commit_transaction->t_log_start = journal->j_head;
	wake_up(&journal->j_wait_transaction_locked);
	spin_unlock(&journal->j_state_lock);

	jbd_debug (3, "JBD: commit phase 2\n");

	/*
	 * Now start flushing things to disk, in the order they appear
	 * on the transaction lists.  Data blocks go first.
	 */
	err = journal_submit_data_buffers(journal, commit_transaction);

	/*
	 * Wait for all previously submitted IO to complete.
	 */
	spin_lock(&journal->j_list_lock);
	while (commit_transaction->t_locked_list) {
		struct buffer_head *bh;

		jh = commit_transaction->t_locked_list->b_tprev;
		bh = jh2bh(jh);
		get_bh(bh);
		if (buffer_locked(bh)) {
			spin_unlock(&journal->j_list_lock);
			wait_on_buffer(bh);
			spin_lock(&journal->j_list_lock);
		}
		if (unlikely(!buffer_uptodate(bh))) {
			if (!trylock_page(bh->b_page)) {
				spin_unlock(&journal->j_list_lock);
				lock_page(bh->b_page);
				spin_lock(&journal->j_list_lock);
			}
			if (bh->b_page->mapping)
				set_bit(AS_EIO, &bh->b_page->mapping->flags);

			unlock_page(bh->b_page);
			SetPageError(bh->b_page);
			err = -EIO;
		}
		if (!inverted_lock(journal, bh)) {
			put_bh(bh);
			spin_lock(&journal->j_list_lock);
			continue;
		}
		if (buffer_jbd(bh) && jh->b_jlist == BJ_Locked) {
			__journal_unfile_buffer(jh);
			jbd_unlock_bh_state(bh);
			journal_remove_journal_head(bh);
			put_bh(bh);
		} else {
			jbd_unlock_bh_state(bh);
		}
		release_data_buffer(bh);
		cond_resched_lock(&journal->j_list_lock);
	}
	spin_unlock(&journal->j_list_lock);

	if (err) {
		char b[BDEVNAME_SIZE];

		printk(KERN_WARNING
			"JBD: Detected IO errors while flushing file data "
			"on %s\n", bdevname(journal->j_fs_dev, b));
		err = 0;
	}

	journal_write_revoke_records(journal, commit_transaction);

	/*
	 * If we found any dirty or locked buffers, then we should have
	 * looped back up to the write_out_data label.  If there weren't
	 * any then journal_clean_data_list should have wiped the list
	 * clean by now, so check that it is in fact empty.
	 */
	J_ASSERT (commit_transaction->t_sync_datalist == NULL);

	jbd_debug (3, "JBD: commit phase 3\n");

	/*
	 * Way to go: we have now written out all of the data for a
	 * transaction!  Now comes the tricky part: we need to write out
	 * metadata.  Loop over the transaction's entire buffer list:
	 */
	spin_lock(&journal->j_state_lock);
	commit_transaction->t_state = T_COMMIT;
	spin_unlock(&journal->j_state_lock);

	J_ASSERT(commit_transaction->t_nr_buffers <=
		 commit_transaction->t_outstanding_credits);

	descriptor = NULL;
	bufs = 0;
	while (commit_transaction->t_buffers) {

		/* Find the next buffer to be journaled... */

		jh = commit_transaction->t_buffers;

		/* If we're in abort mode, we just un-journal the buffer and
		   release it for background writing. */

		if (is_journal_aborted(journal)) {
			JBUFFER_TRACE(jh, "journal is aborting: refile");
			journal_refile_buffer(journal, jh);
			/* If that was the last one, we need to clean up
			 * any descriptor buffers which may have been
			 * already allocated, even if we are now
			 * aborting. */
			if (!commit_transaction->t_buffers)
				goto start_journal_io;
			continue;
		}

		/* Make sure we have a descriptor block in which to
		   record the metadata buffer. */

		if (!descriptor) {
			struct buffer_head *bh;

			J_ASSERT (bufs == 0);

			jbd_debug(4, "JBD: get descriptor\n");

			descriptor = journal_get_descriptor_buffer(journal);
			if (!descriptor) {
				journal_abort(journal, -EIO);
				continue;
			}

			bh = jh2bh(descriptor);
			jbd_debug(4, "JBD: got buffer %llu (%p)\n",
				(unsigned long long)bh->b_blocknr, bh->b_data);
			header = (journal_header_t *)&bh->b_data[0];
			header->h_magic     = cpu_to_be32(JFS_MAGIC_NUMBER);
			header->h_blocktype = cpu_to_be32(JFS_DESCRIPTOR_BLOCK);
			header->h_sequence  = cpu_to_be32(commit_transaction->t_tid);

			tagp = &bh->b_data[sizeof(journal_header_t)];
			space_left = bh->b_size - sizeof(journal_header_t);
			first_tag = 1;
			set_buffer_jwrite(bh);
			set_buffer_dirty(bh);
			wbuf[bufs++] = bh;

			/* Record it so that we can wait for IO
                           completion later */
			BUFFER_TRACE(bh, "ph3: file as descriptor");
			journal_file_buffer(descriptor, commit_transaction,
					BJ_LogCtl);
		}

		/* Where is the buffer to be written? */

		err = journal_next_log_block(journal, &blocknr);
		/* If the block mapping failed, just abandon the buffer
		   and repeat this loop: we'll fall into the
		   refile-on-abort condition above. */
		if (err) {
			journal_abort(journal, err);
			continue;
		}

		/*
		 * start_this_handle() uses t_outstanding_credits to determine
		 * the free space in the log, but this counter is changed
		 * by journal_next_log_block() also.
		 */
		commit_transaction->t_outstanding_credits--;

		/* Bump b_count to prevent truncate from stumbling over
                   the shadowed buffer!  @@@ This can go if we ever get
                   rid of the BJ_IO/BJ_Shadow pairing of buffers. */
		atomic_inc(&jh2bh(jh)->b_count);

		/* Make a temporary IO buffer with which to write it out
                   (this will requeue both the metadata buffer and the
                   temporary IO buffer). new_bh goes on BJ_IO*/

		set_bit(BH_JWrite, &jh2bh(jh)->b_state);
		/*
		 * akpm: journal_write_metadata_buffer() sets
		 * new_bh->b_transaction to commit_transaction.
		 * We need to clean this up before we release new_bh
		 * (which is of type BJ_IO)
		 */
		JBUFFER_TRACE(jh, "ph3: write metadata");
		flags = journal_write_metadata_buffer(commit_transaction,
						      jh, &new_jh, blocknr);
		set_bit(BH_JWrite, &jh2bh(new_jh)->b_state);
		wbuf[bufs++] = jh2bh(new_jh);

		/* Record the new block's tag in the current descriptor
                   buffer */

		tag_flag = 0;
		if (flags & 1)
			tag_flag |= JFS_FLAG_ESCAPE;
		if (!first_tag)
			tag_flag |= JFS_FLAG_SAME_UUID;

		tag = (journal_block_tag_t *) tagp;
		tag->t_blocknr = cpu_to_be32(jh2bh(jh)->b_blocknr);
		tag->t_flags = cpu_to_be32(tag_flag);
		tagp += sizeof(journal_block_tag_t);
		space_left -= sizeof(journal_block_tag_t);

		if (first_tag) {
			memcpy (tagp, journal->j_uuid, 16);
			tagp += 16;
			space_left -= 16;
			first_tag = 0;
		}

		/* If there's no more to do, or if the descriptor is full,
		   let the IO rip! */

		if (bufs == journal->j_wbufsize ||
		    commit_transaction->t_buffers == NULL ||
		    space_left < sizeof(journal_block_tag_t) + 16) {

			jbd_debug(4, "JBD: Submit %d IOs\n", bufs);

			/* Write an end-of-descriptor marker before
                           submitting the IOs.  "tag" still points to
                           the last tag we set up. */

			tag->t_flags |= cpu_to_be32(JFS_FLAG_LAST_TAG);

start_journal_io:
			for (i = 0; i < bufs; i++) {
				struct buffer_head *bh = wbuf[i];
				lock_buffer(bh);
				clear_buffer_dirty(bh);
				set_buffer_uptodate(bh);
				bh->b_end_io = journal_end_buffer_io_sync;
				submit_bh(WRITE, bh);
			}
			cond_resched();

			/* Force a new descriptor to be generated next
                           time round the loop. */
			descriptor = NULL;
			bufs = 0;
		}
	}

	/* Lo and behold: we have just managed to send a transaction to
           the log.  Before we can commit it, wait for the IO so far to
           complete.  Control buffers being written are on the
           transaction's t_log_list queue, and metadata buffers are on
           the t_iobuf_list queue.

	   Wait for the buffers in reverse order.  That way we are
	   less likely to be woken up until all IOs have completed, and
	   so we incur less scheduling load.
	*/

	jbd_debug(3, "JBD: commit phase 4\n");

	/*
	 * akpm: these are BJ_IO, and j_list_lock is not needed.
	 * See __journal_try_to_free_buffer.
	 */
wait_for_iobuf:
	while (commit_transaction->t_iobuf_list != NULL) {
		struct buffer_head *bh;

		jh = commit_transaction->t_iobuf_list->b_tprev;
		bh = jh2bh(jh);
		if (buffer_locked(bh)) {
			wait_on_buffer(bh);
			goto wait_for_iobuf;
		}
		if (cond_resched())
			goto wait_for_iobuf;

		if (unlikely(!buffer_uptodate(bh)))
			err = -EIO;

		clear_buffer_jwrite(bh);

		JBUFFER_TRACE(jh, "ph4: unfile after journal write");
		journal_unfile_buffer(journal, jh);

		/*
		 * ->t_iobuf_list should contain only dummy buffer_heads
		 * which were created by journal_write_metadata_buffer().
		 */
		BUFFER_TRACE(bh, "dumping temporary bh");
		journal_put_journal_head(jh);
		__brelse(bh);
		J_ASSERT_BH(bh, atomic_read(&bh->b_count) == 0);
		free_buffer_head(bh);

		/* We also have to unlock and free the corresponding
                   shadowed buffer */
		jh = commit_transaction->t_shadow_list->b_tprev;
		bh = jh2bh(jh);
		clear_bit(BH_JWrite, &bh->b_state);
		J_ASSERT_BH(bh, buffer_jbddirty(bh));

		/* The metadata is now released for reuse, but we need
                   to remember it against this transaction so that when
                   we finally commit, we can do any checkpointing
                   required. */
		JBUFFER_TRACE(jh, "file as BJ_Forget");
		journal_file_buffer(jh, commit_transaction, BJ_Forget);
		/* Wake up any transactions which were waiting for this
		   IO to complete */
		wake_up_bit(&bh->b_state, BH_Unshadow);
		JBUFFER_TRACE(jh, "brelse shadowed buffer");
		__brelse(bh);
	}

	J_ASSERT (commit_transaction->t_shadow_list == NULL);

	jbd_debug(3, "JBD: commit phase 5\n");

	/* Here we wait for the revoke record and descriptor record buffers */
 wait_for_ctlbuf:
	while (commit_transaction->t_log_list != NULL) {
		struct buffer_head *bh;

		jh = commit_transaction->t_log_list->b_tprev;
		bh = jh2bh(jh);
		if (buffer_locked(bh)) {
			wait_on_buffer(bh);
			goto wait_for_ctlbuf;
		}
		if (cond_resched())
			goto wait_for_ctlbuf;

		if (unlikely(!buffer_uptodate(bh)))
			err = -EIO;

		BUFFER_TRACE(bh, "ph5: control buffer writeout done: unfile");
		clear_buffer_jwrite(bh);
		journal_unfile_buffer(journal, jh);
		journal_put_journal_head(jh);
		__brelse(bh);		/* One for getblk */
		/* AKPM: bforget here */
	}

	jbd_debug(3, "JBD: commit phase 6\n");

	if (journal_write_commit_record(journal, commit_transaction))
		err = -EIO;

	if (err)
		journal_abort(journal, err);

	/* End of a transaction!  Finally, we can do checkpoint
           processing: any buffers committed as a result of this
           transaction can be removed from any checkpoint list it was on
           before. */

	jbd_debug(3, "JBD: commit phase 7\n");

	J_ASSERT(commit_transaction->t_sync_datalist == NULL);
	J_ASSERT(commit_transaction->t_buffers == NULL);
	J_ASSERT(commit_transaction->t_checkpoint_list == NULL);
	J_ASSERT(commit_transaction->t_iobuf_list == NULL);
	J_ASSERT(commit_transaction->t_shadow_list == NULL);
	J_ASSERT(commit_transaction->t_log_list == NULL);

restart_loop:
	/*
	 * As there are other places (journal_unmap_buffer()) adding buffers
	 * to this list we have to be careful and hold the j_list_lock.
	 */
	spin_lock(&journal->j_list_lock);
	while (commit_transaction->t_forget) {
		transaction_t *cp_transaction;
		struct buffer_head *bh;

		jh = commit_transaction->t_forget;
		spin_unlock(&journal->j_list_lock);
		bh = jh2bh(jh);
		jbd_lock_bh_state(bh);
		J_ASSERT_JH(jh,	jh->b_transaction == commit_transaction ||
			jh->b_transaction == journal->j_running_transaction);

		/*
		 * If there is undo-protected committed data against
		 * this buffer, then we can remove it now.  If it is a
		 * buffer needing such protection, the old frozen_data
		 * field now points to a committed version of the
		 * buffer, so rotate that field to the new committed
		 * data.
		 *
		 * Otherwise, we can just throw away the frozen data now.
		 */
		if (jh->b_committed_data) {
			jbd_free(jh->b_committed_data, bh->b_size);
			jh->b_committed_data = NULL;
			if (jh->b_frozen_data) {
				jh->b_committed_data = jh->b_frozen_data;
				jh->b_frozen_data = NULL;
			}
		} else if (jh->b_frozen_data) {
			jbd_free(jh->b_frozen_data, bh->b_size);
			jh->b_frozen_data = NULL;
		}

		spin_lock(&journal->j_list_lock);
		cp_transaction = jh->b_cp_transaction;
		if (cp_transaction) {
			JBUFFER_TRACE(jh, "remove from old cp transaction");
			__journal_remove_checkpoint(jh);
		}

		/* Only re-checkpoint the buffer_head if it is marked
		 * dirty.  If the buffer was added to the BJ_Forget list
		 * by journal_forget, it may no longer be dirty and
		 * there's no point in keeping a checkpoint record for
		 * it. */

		/* A buffer which has been freed while still being
		 * journaled by a previous transaction may end up still
		 * being dirty here, but we want to avoid writing back
		 * that buffer in the future now that the last use has
		 * been committed.  That's not only a performance gain,
		 * it also stops aliasing problems if the buffer is left
		 * behind for writeback and gets reallocated for another
		 * use in a different page. */
		if (buffer_freed(bh)) {
			clear_buffer_freed(bh);
			clear_buffer_jbddirty(bh);
		}

		if (buffer_jbddirty(bh)) {
			JBUFFER_TRACE(jh, "add to new checkpointing trans");
			__journal_insert_checkpoint(jh, commit_transaction);
			JBUFFER_TRACE(jh, "refile for checkpoint writeback");
			__journal_refile_buffer(jh);
			jbd_unlock_bh_state(bh);
		} else {
			J_ASSERT_BH(bh, !buffer_dirty(bh));
			/* The buffer on BJ_Forget list and not jbddirty means
			 * it has been freed by this transaction and hence it
			 * could not have been reallocated until this
			 * transaction has committed. *BUT* it could be
			 * reallocated once we have written all the data to
			 * disk and before we process the buffer on BJ_Forget
			 * list. */
			JBUFFER_TRACE(jh, "refile or unfile freed buffer");
			__journal_refile_buffer(jh);
			if (!jh->b_transaction) {
				jbd_unlock_bh_state(bh);
				 /* needs a brelse */
				journal_remove_journal_head(bh);
				release_buffer_page(bh);
			} else
				jbd_unlock_bh_state(bh);
		}
		cond_resched_lock(&journal->j_list_lock);
	}
	spin_unlock(&journal->j_list_lock);
	/*
	 * This is a bit sleazy.  We use j_list_lock to protect transition
	 * of a transaction into T_FINISHED state and calling
	 * __journal_drop_transaction(). Otherwise we could race with
	 * other checkpointing code processing the transaction...
	 */
	spin_lock(&journal->j_state_lock);
	spin_lock(&journal->j_list_lock);
	/*
	 * Now recheck if some buffers did not get attached to the transaction
	 * while the lock was dropped...
	 */
	if (commit_transaction->t_forget) {
		spin_unlock(&journal->j_list_lock);
		spin_unlock(&journal->j_state_lock);
		goto restart_loop;
	}

	/* Done with this transaction! */

	jbd_debug(3, "JBD: commit phase 8\n");

	J_ASSERT(commit_transaction->t_state == T_COMMIT);

	commit_transaction->t_state = T_FINISHED;
	J_ASSERT(commit_transaction == journal->j_committing_transaction);
	journal->j_commit_sequence = commit_transaction->t_tid;
	journal->j_committing_transaction = NULL;
	spin_unlock(&journal->j_state_lock);

	if (commit_transaction->t_checkpoint_list == NULL &&
	    commit_transaction->t_checkpoint_io_list == NULL) {
		__journal_drop_transaction(journal, commit_transaction);
	} else {
		if (journal->j_checkpoint_transactions == NULL) {
			journal->j_checkpoint_transactions = commit_transaction;
			commit_transaction->t_cpnext = commit_transaction;
			commit_transaction->t_cpprev = commit_transaction;
		} else {
			commit_transaction->t_cpnext =
				journal->j_checkpoint_transactions;
			commit_transaction->t_cpprev =
				commit_transaction->t_cpnext->t_cpprev;
			commit_transaction->t_cpnext->t_cpprev =
				commit_transaction;
			commit_transaction->t_cpprev->t_cpnext =
				commit_transaction;
		}
	}
	spin_unlock(&journal->j_list_lock);

	jbd_debug(1, "JBD: commit %d complete, head %d\n",
		  journal->j_commit_sequence, journal->j_tail_sequence);

	wake_up(&journal->j_wait_done_commit);
}
Beispiel #5
0
/* ent thread function */
static int entd(void *arg)
{
	struct super_block *super;
	entd_context *ent;
	int done = 0;

	super = arg;
	/* do_fork() just copies task_struct into the new
	   thread. ->fs_context shouldn't be copied of course. This shouldn't
	   be a problem for the rest of the code though.
	 */
	current->journal_info = NULL;

	ent = get_entd_context(super);

	while (!done) {
		try_to_freeze();

		spin_lock(&ent->guard);
		while (ent->nr_todo_reqs != 0) {
			struct wbq *rq;

			assert("", list_empty(&ent->done_list));

			/* take request from the queue head */
			rq = __get_wbq(ent);
			assert("", rq != NULL);
			ent->cur_request = rq;
			spin_unlock(&ent->guard);

			entd_set_comm("!");
			entd_flush(super, rq);

			put_wbq(rq);

			/*
			 * wakeup all requestors and iput their inodes
			 */
			spin_lock(&ent->guard);
			while (!list_empty(&ent->done_list)) {
				rq = list_entry(ent->done_list.next, struct wbq, link);
				list_del_init(&rq->link);
				ent->nr_done_reqs--;
				spin_unlock(&ent->guard);
				assert("", rq->written == 1);
				put_wbq(rq);
				spin_lock(&ent->guard);
			}
		}
		spin_unlock(&ent->guard);

		entd_set_comm(".");

		{
			DEFINE_WAIT(__wait);

			do {
				prepare_to_wait(&ent->wait, &__wait, TASK_INTERRUPTIBLE);
				if (kthread_should_stop()) {
					done = 1;
					break;
				}
				if (ent->nr_todo_reqs != 0)
					break;
				schedule();
			} while (0);
			finish_wait(&ent->wait, &__wait);
		}
	}
	BUG_ON(ent->nr_todo_reqs != 0);
	return 0;
}
Beispiel #6
0
int rtlx_open(int index, int can_sleep)
{
	struct rtlx_info **p;
	struct rtlx_channel *chan;
	enum rtlx_state state;
	int ret = 0;

	if (index >= RTLX_CHANNELS) {
		printk(KERN_DEBUG "rtlx_open index out of range\n");
		return -ENOSYS;
	}

	if (atomic_inc_return(&channel_wqs[index].in_open) > 1) {
		printk(KERN_DEBUG "rtlx_open channel %d already opened\n",
		       index);
		ret = -EBUSY;
		goto out_fail;
	}

	if (rtlx == NULL) {
		if( (p = vpe_get_shared(tclimit)) == NULL) {
		    if (can_sleep) {
			__wait_event_interruptible(channel_wqs[index].lx_queue,
				(p = vpe_get_shared(tclimit)), ret);
			if (ret)
				goto out_fail;
		    } else {
			printk(KERN_DEBUG "No SP program loaded, and device "
					"opened with O_NONBLOCK\n");
			ret = -ENOSYS;
			goto out_fail;
		    }
		}

		smp_rmb();
		if (*p == NULL) {
			if (can_sleep) {
				DEFINE_WAIT(wait);

				for (;;) {
					prepare_to_wait(
						&channel_wqs[index].lx_queue,
						&wait, TASK_INTERRUPTIBLE);
					smp_rmb();
					if (*p != NULL)
						break;
					if (!signal_pending(current)) {
						schedule();
						continue;
					}
					ret = -ERESTARTSYS;
					goto out_fail;
				}
				finish_wait(&channel_wqs[index].lx_queue, &wait);
			} else {
				pr_err(" *vpe_get_shared is NULL. "
				       "Has an SP program been loaded?\n");
				ret = -ENOSYS;
				goto out_fail;
			}
		}

		if ((unsigned int)*p < KSEG0) {
			printk(KERN_WARNING "vpe_get_shared returned an "
			       "invalid pointer maybe an error code %d\n",
			       (int)*p);
			ret = -ENOSYS;
			goto out_fail;
		}

		if ((ret = rtlx_init(*p)) < 0)
			goto out_ret;
	}

	chan = &rtlx->channel[index];

	state = xchg(&chan->lx_state, RTLX_STATE_OPENED);
	if (state == RTLX_STATE_OPENED) {
		ret = -EBUSY;
		goto out_fail;
	}

out_fail:
	smp_mb();
	atomic_dec(&channel_wqs[index].in_open);
	smp_mb();

out_ret:
	return ret;
}
Beispiel #7
0
int
islpci_mgt_transaction(struct net_device *ndev,
		       int operation, unsigned long oid,
		       void *senddata, int sendlen,
		       struct islpci_mgmtframe **recvframe)
{
	islpci_private *priv = netdev_priv(ndev);
	const long wait_cycle_jiffies = msecs_to_jiffies(ISL38XX_WAIT_CYCLE * 10);
	long timeout_left = ISL38XX_MAX_WAIT_CYCLES * wait_cycle_jiffies;
	int err;
	DEFINE_WAIT(wait);

	*recvframe = NULL;

	if (mutex_lock_interruptible(&priv->mgmt_lock))
		return -ERESTARTSYS;

	prepare_to_wait(&priv->mgmt_wqueue, &wait, TASK_UNINTERRUPTIBLE);
	err = islpci_mgt_transmit(ndev, operation, oid, senddata, sendlen);
	if (err)
		goto out;

	err = -ETIMEDOUT;
	while (timeout_left > 0) {
		int timeleft;
		struct islpci_mgmtframe *frame;

		timeleft = schedule_timeout_uninterruptible(wait_cycle_jiffies);
		frame = xchg(&priv->mgmt_received, NULL);
		if (frame) {
			if (frame->header->oid == oid) {
				*recvframe = frame;
				err = 0;
				goto out;
			} else {
				printk(KERN_DEBUG
				       "%s: expecting oid 0x%x, received 0x%x.\n",
				       ndev->name, (unsigned int) oid,
				       frame->header->oid);
				kfree(frame);
				frame = NULL;
			}
		}
		if (timeleft == 0) {
			printk(KERN_DEBUG
				"%s: timeout waiting for mgmt response %lu, "
				"triggering device\n",
				ndev->name, timeout_left);
			islpci_trigger(priv);
		}
		timeout_left += timeleft - wait_cycle_jiffies;
	}
	printk(KERN_WARNING "%s: timeout waiting for mgmt response\n",
	       ndev->name);

	
 out:
	finish_wait(&priv->mgmt_wqueue, &wait);
	mutex_unlock(&priv->mgmt_lock);
	return err;
}
Beispiel #8
0
ssize_t ivtv_v4l2_write(struct file *filp, const char __user *user_buf, size_t count, loff_t *pos)
{
	struct ivtv_open_id *id = fh2id(filp->private_data);
	struct ivtv *itv = id->itv;
	struct ivtv_stream *s = &itv->streams[id->type];
	struct yuv_playback_info *yi = &itv->yuv_info;
	struct ivtv_buffer *buf;
	struct ivtv_queue q;
	int bytes_written = 0;
	int mode;
	int rc;
	DEFINE_WAIT(wait);

	IVTV_DEBUG_HI_FILE("write %zd bytes to %s\n", count, s->name);

	if (s->type != IVTV_DEC_STREAM_TYPE_MPG &&
	    s->type != IVTV_DEC_STREAM_TYPE_YUV &&
	    s->type != IVTV_DEC_STREAM_TYPE_VOUT)
		/* not decoder streams */
		return -EPERM;

	/* Try to claim this stream */
	if (ivtv_claim_stream(id, s->type))
		return -EBUSY;

	/* This stream does not need to start any decoding */
	if (s->type == IVTV_DEC_STREAM_TYPE_VOUT) {
		int elems = count / sizeof(struct v4l2_sliced_vbi_data);

		set_bit(IVTV_F_S_APPL_IO, &s->s_flags);
		return ivtv_write_vbi_from_user(itv,
		   (const struct v4l2_sliced_vbi_data __user *)user_buf, elems);
	}

	mode = s->type == IVTV_DEC_STREAM_TYPE_MPG ? OUT_MPG : OUT_YUV;

	if (ivtv_set_output_mode(itv, mode) != mode) {
	    ivtv_release_stream(s);
	    return -EBUSY;
	}
	ivtv_queue_init(&q);
	set_bit(IVTV_F_S_APPL_IO, &s->s_flags);

	/* Start decoder (returns 0 if already started) */
	mutex_lock(&itv->serialize_lock);
	rc = ivtv_start_decoding(id, itv->speed);
	mutex_unlock(&itv->serialize_lock);
	if (rc) {
		IVTV_DEBUG_WARN("Failed start decode stream %s\n", s->name);

		/* failure, clean up */
		clear_bit(IVTV_F_S_STREAMING, &s->s_flags);
		clear_bit(IVTV_F_S_APPL_IO, &s->s_flags);
		return rc;
	}

retry:
	/* If possible, just DMA the entire frame - Check the data transfer size
	since we may get here before the stream has been fully set-up */
	if (mode == OUT_YUV && s->q_full.length == 0 && itv->dma_data_req_size) {
		while (count >= itv->dma_data_req_size) {
			rc = ivtv_yuv_udma_stream_frame(itv, (void __user *)user_buf);

			if (rc < 0)
				return rc;

			bytes_written += itv->dma_data_req_size;
			user_buf += itv->dma_data_req_size;
			count -= itv->dma_data_req_size;
		}
		if (count == 0) {
			IVTV_DEBUG_HI_FILE("Wrote %d bytes to %s (%d)\n", bytes_written, s->name, s->q_full.bytesused);
			return bytes_written;
		}
	}

	for (;;) {
		/* Gather buffers */
		while (q.length - q.bytesused < count && (buf = ivtv_dequeue(s, &s->q_io)))
			ivtv_enqueue(s, buf, &q);
		while (q.length - q.bytesused < count && (buf = ivtv_dequeue(s, &s->q_free))) {
			ivtv_enqueue(s, buf, &q);
		}
		if (q.buffers)
			break;
		if (filp->f_flags & O_NONBLOCK)
			return -EAGAIN;
		prepare_to_wait(&s->waitq, &wait, TASK_INTERRUPTIBLE);
		/* New buffers might have become free before we were added to the waitqueue */
		if (!s->q_free.buffers)
			schedule();
		finish_wait(&s->waitq, &wait);
		if (signal_pending(current)) {
			IVTV_DEBUG_INFO("User stopped %s\n", s->name);
			return -EINTR;
		}
	}

	/* copy user data into buffers */
	while ((buf = ivtv_dequeue(s, &q))) {
		/* yuv is a pain. Don't copy more data than needed for a single
		   frame, otherwise we lose sync with the incoming stream */
		if (s->type == IVTV_DEC_STREAM_TYPE_YUV &&
		    yi->stream_size + count > itv->dma_data_req_size)
			rc  = ivtv_buf_copy_from_user(s, buf, user_buf,
				itv->dma_data_req_size - yi->stream_size);
		else
			rc = ivtv_buf_copy_from_user(s, buf, user_buf, count);

		/* Make sure we really got all the user data */
		if (rc < 0) {
			ivtv_queue_move(s, &q, NULL, &s->q_free, 0);
			return rc;
		}
		user_buf += rc;
		count -= rc;
		bytes_written += rc;

		if (s->type == IVTV_DEC_STREAM_TYPE_YUV) {
			yi->stream_size += rc;
			/* If we have a complete yuv frame, break loop now */
			if (yi->stream_size == itv->dma_data_req_size) {
				ivtv_enqueue(s, buf, &s->q_full);
				yi->stream_size = 0;
				break;
			}
		}

		if (buf->bytesused != s->buf_size) {
			/* incomplete, leave in q_io for next time */
			ivtv_enqueue(s, buf, &s->q_io);
			break;
		}
		/* Byteswap MPEG buffer */
		if (s->type == IVTV_DEC_STREAM_TYPE_MPG)
			ivtv_buf_swap(buf);
		ivtv_enqueue(s, buf, &s->q_full);
	}

	if (test_bit(IVTV_F_S_NEEDS_DATA, &s->s_flags)) {
		if (s->q_full.length >= itv->dma_data_req_size) {
			int got_sig;

			if (mode == OUT_YUV)
				ivtv_yuv_setup_stream_frame(itv);

			prepare_to_wait(&itv->dma_waitq, &wait, TASK_INTERRUPTIBLE);
			while (!(got_sig = signal_pending(current)) &&
					test_bit(IVTV_F_S_DMA_PENDING, &s->s_flags)) {
				schedule();
			}
			finish_wait(&itv->dma_waitq, &wait);
			if (got_sig) {
				IVTV_DEBUG_INFO("User interrupted %s\n", s->name);
				return -EINTR;
			}

			clear_bit(IVTV_F_S_NEEDS_DATA, &s->s_flags);
			ivtv_queue_move(s, &s->q_full, NULL, &s->q_predma, itv->dma_data_req_size);
			ivtv_dma_stream_dec_prepare(s, itv->dma_data_req_offset + IVTV_DECODER_OFFSET, 1);
		}
	}
	/* more user data is available, wait until buffers become free
	   to transfer the rest. */
	if (count && !(filp->f_flags & O_NONBLOCK))
		goto retry;
	IVTV_DEBUG_HI_FILE("Wrote %d bytes to %s (%d)\n", bytes_written, s->name, s->q_full.bytesused);
	return bytes_written;
}
Beispiel #9
0
/**
 * sk_stream_wait_memory - Wait for more memory for a socket
 * @sk: socket to wait for memory
 * @timeo_p: for how long
 * @amount - amount of memory to wait for (in UB space!)
 */
int __sk_stream_wait_memory(struct sock *sk, long *timeo_p,
		unsigned long amount)
{
	int err = 0;
	long vm_wait = 0;
	long current_timeo = *timeo_p;
	DEFINE_WAIT(wait);

	if (sk_stream_memory_free(sk))
		current_timeo = vm_wait = (net_random() % (HZ / 5)) + 2;

	while (1) {
		set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);

		prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);

		if (sk->sk_err || (sk->sk_shutdown & SEND_SHUTDOWN))
			goto do_error;
		if (!*timeo_p)
			goto do_nonblock;
		if (signal_pending(current))
			goto do_interrupted;
		clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
		if (amount == 0) {
			if (sk_stream_memory_free(sk) && !vm_wait)
				break;
		} else if (!ub_sock_sndqueueadd_tcp(sk, amount))
			break;

		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
		sk->sk_write_pending++;
		sk_wait_event(sk, &current_timeo, sk->sk_err ||
						  (sk->sk_shutdown & SEND_SHUTDOWN) ||
						  (sk_stream_memory_free(sk) &&
						  !vm_wait));
		sk->sk_write_pending--;
		if (amount > 0)
			ub_sock_sndqueuedel(sk);

		if (vm_wait) {
			vm_wait -= current_timeo;
			current_timeo = *timeo_p;
			if (current_timeo != MAX_SCHEDULE_TIMEOUT &&
			    (current_timeo -= vm_wait) < 0)
				current_timeo = 0;
			vm_wait = 0;
		}
		*timeo_p = current_timeo;
	}
out:
	finish_wait(sk->sk_sleep, &wait);
	return err;

do_error:
	err = -EPIPE;
	goto out;
do_nonblock:
	err = -EAGAIN;
	goto out;
do_interrupted:
	err = sock_intr_errno(*timeo_p);
	goto out;
}
Beispiel #10
0
static int pep_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
{
	struct pep_sock *pn = pep_sk(sk);
	struct sk_buff *skb;
	long timeo;
	int flags = msg->msg_flags;
	int err, done;

	if (len > USHRT_MAX)
		return -EMSGSIZE;

	if ((msg->msg_flags & ~(MSG_DONTWAIT|MSG_EOR|MSG_NOSIGNAL|
				MSG_CMSG_COMPAT)) ||
			!(msg->msg_flags & MSG_EOR))
		return -EOPNOTSUPP;

	skb = sock_alloc_send_skb(sk, MAX_PNPIPE_HEADER + len,
					flags & MSG_DONTWAIT, &err);
	if (!skb)
		return err;

	skb_reserve(skb, MAX_PHONET_HEADER + 3 + pn->aligned);
	err = memcpy_from_msg(skb_put(skb, len), msg, len);
	if (err < 0)
		goto outfree;

	lock_sock(sk);
	timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT);
	if ((1 << sk->sk_state) & (TCPF_LISTEN|TCPF_CLOSE)) {
		err = -ENOTCONN;
		goto out;
	}
	if (sk->sk_state != TCP_ESTABLISHED) {
		/* Wait until the pipe gets to enabled state */
disabled:
		err = sk_stream_wait_connect(sk, &timeo);
		if (err)
			goto out;

		if (sk->sk_state == TCP_CLOSE_WAIT) {
			err = -ECONNRESET;
			goto out;
		}
	}
	BUG_ON(sk->sk_state != TCP_ESTABLISHED);

	/* Wait until flow control allows TX */
	done = atomic_read(&pn->tx_credits);
	while (!done) {
		DEFINE_WAIT(wait);

		if (!timeo) {
			err = -EAGAIN;
			goto out;
		}
		if (signal_pending(current)) {
			err = sock_intr_errno(timeo);
			goto out;
		}

		prepare_to_wait(sk_sleep(sk), &wait,
				TASK_INTERRUPTIBLE);
		done = sk_wait_event(sk, &timeo, atomic_read(&pn->tx_credits));
		finish_wait(sk_sleep(sk), &wait);

		if (sk->sk_state != TCP_ESTABLISHED)
			goto disabled;
	}

	err = pipe_skb_send(sk, skb);
	if (err >= 0)
		err = len; /* success! */
	skb = NULL;
out:
	release_sock(sk);
outfree:
	kfree_skb(skb);
	return err;
}
Beispiel #11
0
static struct ivtv_buffer *ivtv_get_buffer(struct ivtv_stream *s, int non_block, int *err)
{
	struct ivtv *itv = s->itv;
	struct ivtv_stream *s_vbi = &itv->streams[IVTV_ENC_STREAM_TYPE_VBI];
	struct ivtv_buffer *buf;
	DEFINE_WAIT(wait);

	*err = 0;
	while (1) {
		if (s->type == IVTV_ENC_STREAM_TYPE_MPG) {
			/* Process pending program info updates and pending VBI data */
			ivtv_update_pgm_info(itv);

			if (time_after(jiffies,
				       itv->dualwatch_jiffies +
				       msecs_to_jiffies(1000))) {
				itv->dualwatch_jiffies = jiffies;
				ivtv_dualwatch(itv);
			}

			if (test_bit(IVTV_F_S_INTERNAL_USE, &s_vbi->s_flags) &&
			    !test_bit(IVTV_F_S_APPL_IO, &s_vbi->s_flags)) {
				while ((buf = ivtv_dequeue(s_vbi, &s_vbi->q_full))) {
					/* byteswap and process VBI data */
					ivtv_process_vbi_data(itv, buf, s_vbi->dma_pts, s_vbi->type);
					ivtv_enqueue(s_vbi, buf, &s_vbi->q_free);
				}
			}
			buf = &itv->vbi.sliced_mpeg_buf;
			if (buf->readpos != buf->bytesused) {
				return buf;
			}
		}

		/* do we have leftover data? */
		buf = ivtv_dequeue(s, &s->q_io);
		if (buf)
			return buf;

		/* do we have new data? */
		buf = ivtv_dequeue(s, &s->q_full);
		if (buf) {
			if ((buf->b_flags & IVTV_F_B_NEED_BUF_SWAP) == 0)
				return buf;
			buf->b_flags &= ~IVTV_F_B_NEED_BUF_SWAP;
			if (s->type == IVTV_ENC_STREAM_TYPE_MPG)
				/* byteswap MPG data */
				ivtv_buf_swap(buf);
			else if (s->type != IVTV_DEC_STREAM_TYPE_VBI) {
				/* byteswap and process VBI data */
				ivtv_process_vbi_data(itv, buf, s->dma_pts, s->type);
			}
			return buf;
		}

		/* return if end of stream */
		if (s->type != IVTV_DEC_STREAM_TYPE_VBI && !test_bit(IVTV_F_S_STREAMING, &s->s_flags)) {
			IVTV_DEBUG_INFO("EOS %s\n", s->name);
			return NULL;
		}

		/* return if file was opened with O_NONBLOCK */
		if (non_block) {
			*err = -EAGAIN;
			return NULL;
		}

		/* wait for more data to arrive */
		prepare_to_wait(&s->waitq, &wait, TASK_INTERRUPTIBLE);
		/* New buffers might have become available before we were added to the waitqueue */
		if (!s->q_full.buffers)
			schedule();
		finish_wait(&s->waitq, &wait);
		if (signal_pending(current)) {
			/* return if a signal was received */
			IVTV_DEBUG_INFO("User stopped %s\n", s->name);
			*err = -EINTR;
			return NULL;
		}
	}
}
Beispiel #12
0
static int rs_ioctl(struct tty_struct *tty,
		    unsigned int cmd, unsigned long arg)
{
	struct serial_state *info = tty->driver_data;
	struct async_icount cprev, cnow;	/* kernel counter temps */
	void __user *argp = (void __user *)arg;
	unsigned long flags;
	DEFINE_WAIT(wait);
	int ret;

	if (serial_paranoia_check(info, tty->name, "rs_ioctl"))
		return -ENODEV;

	if ((cmd != TIOCSERCONFIG) &&
	    (cmd != TIOCMIWAIT) && (cmd != TIOCGICOUNT)) {
		if (tty_io_error(tty))
		    return -EIO;
	}

	switch (cmd) {
		case TIOCSERCONFIG:
			return 0;

		case TIOCSERGETLSR: /* Get line status register */
			return get_lsr_info(info, argp);

		/*
		 * Wait for any of the 4 modem inputs (DCD,RI,DSR,CTS) to change
		 * - mask passed in arg for lines of interest
 		 *   (use |'ed TIOCM_RNG/DSR/CD/CTS for masking)
		 * Caller should use TIOCGICOUNT to see which one it was
		 */
		case TIOCMIWAIT:
			local_irq_save(flags);
			/* note the counters on entry */
			cprev = info->icount;
			local_irq_restore(flags);
			while (1) {
				prepare_to_wait(&info->tport.delta_msr_wait,
						&wait, TASK_INTERRUPTIBLE);
				local_irq_save(flags);
				cnow = info->icount; /* atomic copy */
				local_irq_restore(flags);
				if (cnow.rng == cprev.rng && cnow.dsr == cprev.dsr && 
				    cnow.dcd == cprev.dcd && cnow.cts == cprev.cts) {
					ret = -EIO; /* no change => error */
					break;
				}
				if ( ((arg & TIOCM_RNG) && (cnow.rng != cprev.rng)) ||
				     ((arg & TIOCM_DSR) && (cnow.dsr != cprev.dsr)) ||
				     ((arg & TIOCM_CD)  && (cnow.dcd != cprev.dcd)) ||
				     ((arg & TIOCM_CTS) && (cnow.cts != cprev.cts)) ) {
					ret = 0;
					break;
				}
				schedule();
				/* see if a signal did it */
				if (signal_pending(current)) {
					ret = -ERESTARTSYS;
					break;
				}
				cprev = cnow;
			}
			finish_wait(&info->tport.delta_msr_wait, &wait);
			return ret;

		default:
			return -ENOIOCTLCMD;
		}
	return 0;
}
/**
 * @brief Lock the mutex.  Also does a data barrier after locking so the
 *        locking is complete before any shared data is accessed.
 * @param[in,out] mutex which mutex to lock
 * @param         mode  mutex lock mode
 * @param file the file of the caller code
 * @param line the line number of the code that called this function
 * @return rc = 0: mutex now locked by caller<br>
 *             < 0: interrupted
 */
int
Mutex_LockLine(Mutex *mutex,
	       MutexMode mode,
	       const char *file,
	       int line)
{
	Mutex_State newState, oldState;

	MutexCheckSleep(file, line);

	/*
	 * If uncontended, just set new lock state and return success status.
	 * If contended, mark state saying there is a waiting thread to wake.
	 */
	do {
lock_start:
		/*
		 * Get current state and calculate what new state would be.
		 * New state adds 1 for shared and 0xFFFF for exclusive.
		 * If the 16 bit field overflows, there is contention.
		 */
		oldState.state = ATOMIC_GETO(mutex->state);
		newState.mode  = oldState.mode + mode;
		newState.blck  = oldState.blck;

		/*
		 * So we are saying there is no contention if new state
		 * indicates no overflow.
		 *
		 * On fairness: The test here allows a new-comer thread to grab
		 * the lock even if there is a blocked thread. For example 2
		 * threads repeatedly obtaining shared access can starve a third
		 * wishing to obtain an exclusive lock. Currently this is only a
		 * hypothetical situation as mksck use exclusive lock only and
		 * the code never has more than 2 threads using the same mutex.
		 */
		if ((uint32)newState.mode >= (uint32)mode) {
			if (!ATOMIC_SETIF(mutex->state, newState.state,
					  oldState.state))
				goto lock_start;

			DMB();
			mutex->line    = line;
			mutex->lineUnl = -1;
			return 0;
		}

		/*
		 * There is contention, so increment the number of blocking
		 * threads.
		 */
		newState.mode = oldState.mode;
		newState.blck = oldState.blck + 1;
	} while (!ATOMIC_SETIF(mutex->state, newState.state, oldState.state));

	/*
	 * Statistics...
	 */
	ATOMIC_ADDV(mutex->blocked, 1);

	/*
	 * Mutex is contended, state has been updated to say there is a blocking
	 * thread.
	 *
	 * So now we block till someone wakes us up.
	 */
	 do {
		DEFINE_WAIT(waiter);

		/*
		 * This will make sure we catch any wakes done after we check
		 * the lock state again.
		 */
		prepare_to_wait((wait_queue_head_t *)mutex->lockWaitQ,
				&waiter,
				TASK_INTERRUPTIBLE);

		/*
		 * Now that we will catch wakes, check the lock state again.
		 * If now uncontended, mark it locked, abandon the wait and
		 * return success.
		 */

set_new_state:
		/*
		 * Same as the original check for contention above, except
		 * that we must decrement the number of waiting threads by one
		 * if we are successful in locking the mutex.
		 */
		oldState.state = ATOMIC_GETO(mutex->state);
		newState.mode  = oldState.mode + mode;
		newState.blck  = oldState.blck - 1;
		ASSERT(oldState.blck);

		if ((uint32)newState.mode >= (uint32)mode) {
			if (!ATOMIC_SETIF(mutex->state,
					  newState.state, oldState.state))
				goto set_new_state;

			/*
			 * No longer contended and we were able to lock it.
			 */
			finish_wait((wait_queue_head_t *)mutex->lockWaitQ,
				    &waiter);
			DMB();
			mutex->line    = line;
			mutex->lineUnl = -1;
			return 0;
		}

		/*
		 * Wait for a wake that happens any time after prepare_to_wait()
		 * returned.
		 */
		WARN(!schedule_timeout(10*HZ),
		     "Mutex_Lock: soft lockup - stuck for 10s!\n");
		finish_wait((wait_queue_head_t *)mutex->lockWaitQ, &waiter);
	} while (!signal_pending(current));

	/*
	 * We aren't waiting anymore, decrement the number of waiting threads.
	 */
	do {
		oldState.state = ATOMIC_GETO(mutex->state);
		newState.mode  = oldState.mode;
		newState.blck  = oldState.blck - 1;

		ASSERT(oldState.blck);
	} while (!ATOMIC_SETIF(mutex->state, newState.state, oldState.state));

	return -ERESTARTSYS;
}
Beispiel #14
0
static void bluecard_write_wakeup(bluecard_info_t *info)
{
	if (!info) {
		BT_ERR("Unknown device");
		return;
	}

	if (!test_bit(XMIT_SENDING_READY, &(info->tx_state)))
		return;

	if (test_and_set_bit(XMIT_SENDING, &(info->tx_state))) {
		set_bit(XMIT_WAKEUP, &(info->tx_state));
		return;
	}

	do {
#if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,36))
		unsigned int iobase = info->p_dev->resource[0]->start;
#else
		unsigned int iobase = info->p_dev->io.BasePort1;
#endif
		unsigned int offset;
		unsigned char command;
		unsigned long ready_bit;
		register struct sk_buff *skb;
		int len;

		clear_bit(XMIT_WAKEUP, &(info->tx_state));

		if (!pcmcia_dev_present(info->p_dev))
			return;

		if (test_bit(XMIT_BUFFER_NUMBER, &(info->tx_state))) {
			if (!test_bit(XMIT_BUF_TWO_READY, &(info->tx_state)))
				break;
			offset = 0x10;
			command = REG_COMMAND_TX_BUF_TWO;
			ready_bit = XMIT_BUF_TWO_READY;
		} else {
			if (!test_bit(XMIT_BUF_ONE_READY, &(info->tx_state)))
				break;
			offset = 0x00;
			command = REG_COMMAND_TX_BUF_ONE;
			ready_bit = XMIT_BUF_ONE_READY;
		}

		if (!(skb = skb_dequeue(&(info->txq))))
			break;

		if (bt_cb(skb)->pkt_type & 0x80) {
			/* Disable RTS */
			info->ctrl_reg |= REG_CONTROL_RTS;
			outb(info->ctrl_reg, iobase + REG_CONTROL);
		}

		/* Activate LED */
		bluecard_enable_activity_led(info);

		/* Send frame */
		len = bluecard_write(iobase, offset, skb->data, skb->len);

		/* Tell the FPGA to send the data */
		outb_p(command, iobase + REG_COMMAND);

		/* Mark the buffer as dirty */
		clear_bit(ready_bit, &(info->tx_state));

		if (bt_cb(skb)->pkt_type & 0x80) {
			DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);
			DEFINE_WAIT(wait);

			unsigned char baud_reg;

			switch (bt_cb(skb)->pkt_type) {
			case PKT_BAUD_RATE_460800:
				baud_reg = REG_CONTROL_BAUD_RATE_460800;
				break;
			case PKT_BAUD_RATE_230400:
				baud_reg = REG_CONTROL_BAUD_RATE_230400;
				break;
			case PKT_BAUD_RATE_115200:
				baud_reg = REG_CONTROL_BAUD_RATE_115200;
				break;
			case PKT_BAUD_RATE_57600:
				/* Fall through... */
			default:
				baud_reg = REG_CONTROL_BAUD_RATE_57600;
				break;
			}

			/* Wait until the command reaches the baseband */
			prepare_to_wait(&wq, &wait, TASK_INTERRUPTIBLE);
			schedule_timeout(HZ/10);
			finish_wait(&wq, &wait);

			/* Set baud on baseband */
			info->ctrl_reg &= ~0x03;
			info->ctrl_reg |= baud_reg;
			outb(info->ctrl_reg, iobase + REG_CONTROL);

			/* Enable RTS */
			info->ctrl_reg &= ~REG_CONTROL_RTS;
			outb(info->ctrl_reg, iobase + REG_CONTROL);

			/* Wait before the next HCI packet can be send */
			prepare_to_wait(&wq, &wait, TASK_INTERRUPTIBLE);
			schedule_timeout(HZ);
			finish_wait(&wq, &wait);
		}

		if (len == skb->len) {
			kfree_skb(skb);
		} else {
			skb_pull(skb, len);
			skb_queue_head(&(info->txq), skb);
		}

		info->hdev->stat.byte_tx += len;

		/* Change buffer */
		change_bit(XMIT_BUFFER_NUMBER, &(info->tx_state));

	} while (test_bit(XMIT_WAKEUP, &(info->tx_state)));

	clear_bit(XMIT_SENDING, &(info->tx_state));
}
Beispiel #15
0
static int vsock_stream_sendmsg(struct kiocb *kiocb, struct socket *sock,
				struct msghdr *msg, size_t len)
{
	struct sock *sk;
	struct vsock_sock *vsk;
	ssize_t total_written;
	long timeout;
	int err;
	struct vsock_transport_send_notify_data send_data;

	DEFINE_WAIT(wait);

	sk = sock->sk;
	vsk = vsock_sk(sk);
	total_written = 0;
	err = 0;

	if (msg->msg_flags & MSG_OOB)
		return -EOPNOTSUPP;

	lock_sock(sk);

	/* Callers should not provide a destination with stream sockets. */
	if (msg->msg_namelen) {
		err = sk->sk_state == SS_CONNECTED ? -EISCONN : -EOPNOTSUPP;
		goto out;
	}

	/* Send data only if both sides are not shutdown in the direction. */
	if (sk->sk_shutdown & SEND_SHUTDOWN ||
	    vsk->peer_shutdown & RCV_SHUTDOWN) {
		err = -EPIPE;
		goto out;
	}

	if (sk->sk_state != SS_CONNECTED ||
	    !vsock_addr_bound(&vsk->local_addr)) {
		err = -ENOTCONN;
		goto out;
	}

	if (!vsock_addr_bound(&vsk->remote_addr)) {
		err = -EDESTADDRREQ;
		goto out;
	}

	/* Wait for room in the produce queue to enqueue our user's data. */
	timeout = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);

	err = transport->notify_send_init(vsk, &send_data);
	if (err < 0)
		goto out;

	prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);

	while (total_written < len) {
		ssize_t written;

		while (vsock_stream_has_space(vsk) == 0 &&
		       sk->sk_err == 0 &&
		       !(sk->sk_shutdown & SEND_SHUTDOWN) &&
		       !(vsk->peer_shutdown & RCV_SHUTDOWN)) {

			/* Don't wait for non-blocking sockets. */
			if (timeout == 0) {
				err = -EAGAIN;
				goto out_wait;
			}

			err = transport->notify_send_pre_block(vsk, &send_data);
			if (err < 0)
				goto out_wait;

			release_sock(sk);
			timeout = schedule_timeout(timeout);
			lock_sock(sk);
			if (signal_pending(current)) {
				err = sock_intr_errno(timeout);
				goto out_wait;
			} else if (timeout == 0) {
				err = -EAGAIN;
				goto out_wait;
			}

			prepare_to_wait(sk_sleep(sk), &wait,
					TASK_INTERRUPTIBLE);
		}

		/* These checks occur both as part of and after the loop
		 * conditional since we need to check before and after
		 * sleeping.
		 */
		if (sk->sk_err) {
			err = -sk->sk_err;
			goto out_wait;
		} else if ((sk->sk_shutdown & SEND_SHUTDOWN) ||
			   (vsk->peer_shutdown & RCV_SHUTDOWN)) {
			err = -EPIPE;
			goto out_wait;
		}

		err = transport->notify_send_pre_enqueue(vsk, &send_data);
		if (err < 0)
			goto out_wait;

		/* Note that enqueue will only write as many bytes as are free
		 * in the produce queue, so we don't need to ensure len is
		 * smaller than the queue size.  It is the caller's
		 * responsibility to check how many bytes we were able to send.
		 */

		written = transport->stream_enqueue(
				vsk, msg->msg_iov,
				len - total_written);
		if (written < 0) {
			err = -ENOMEM;
			goto out_wait;
		}

		total_written += written;

		err = transport->notify_send_post_enqueue(
				vsk, written, &send_data);
		if (err < 0)
			goto out_wait;

	}

out_wait:
	if (total_written > 0)
		err = total_written;
	finish_wait(sk_sleep(sk), &wait);
out:
	release_sock(sk);
	return err;
}
Beispiel #16
0
static int kjournald(void *arg)
{
	journal_t *journal = arg;
	transaction_t *transaction;

	/*
	 * Set up an interval timer which can be used to trigger a commit wakeup
	 * after the commit interval expires
	 */
	setup_timer(&journal->j_commit_timer, commit_timeout,
			(unsigned long)current);

	set_freezable();

	/* Record that the journal thread is running */
	journal->j_task = current;
	wake_up(&journal->j_wait_done_commit);

	printk(KERN_INFO "kjournald starting.  Commit interval %ld seconds\n",
			journal->j_commit_interval / HZ);

	/*
	 * And now, wait forever for commit wakeup events.
	 */
	spin_lock(&journal->j_state_lock);

loop:
	if (journal->j_flags & JFS_UNMOUNT)
		goto end_loop;

	jbd_debug(1, "commit_sequence=%d, commit_request=%d\n",
		journal->j_commit_sequence, journal->j_commit_request);

	if (journal->j_commit_sequence != journal->j_commit_request) {
		jbd_debug(1, "OK, requests differ\n");
		spin_unlock(&journal->j_state_lock);
		del_timer_sync(&journal->j_commit_timer);
		journal_commit_transaction(journal);
		spin_lock(&journal->j_state_lock);
		goto loop;
	}

	wake_up(&journal->j_wait_done_commit);
	if (freezing(current)) {
		/*
		 * The simpler the better. Flushing journal isn't a
		 * good idea, because that depends on threads that may
		 * be already stopped.
		 */
		jbd_debug(1, "Now suspending kjournald\n");
		spin_unlock(&journal->j_state_lock);
		try_to_freeze();
		spin_lock(&journal->j_state_lock);
	} else {
		/*
		 * We assume on resume that commits are already there,
		 * so we don't sleep
		 */
		DEFINE_WAIT(wait);
		int should_sleep = 1;

		prepare_to_wait(&journal->j_wait_commit, &wait,
				TASK_INTERRUPTIBLE);
		if (journal->j_commit_sequence != journal->j_commit_request)
			should_sleep = 0;
		transaction = journal->j_running_transaction;
		if (transaction && time_after_eq(jiffies,
						transaction->t_expires))
			should_sleep = 0;
		if (journal->j_flags & JFS_UNMOUNT)
			should_sleep = 0;
		if (should_sleep) {
			spin_unlock(&journal->j_state_lock);
			schedule();
			spin_lock(&journal->j_state_lock);
		}
		finish_wait(&journal->j_wait_commit, &wait);
	}

	jbd_debug(1, "kjournald wakes\n");

	/*
	 * Were we woken up by a commit wakeup event?
	 */
	transaction = journal->j_running_transaction;
	if (transaction && time_after_eq(jiffies, transaction->t_expires)) {
		journal->j_commit_request = transaction->t_tid;
		jbd_debug(1, "woke because of timeout\n");
	}
	goto loop;

end_loop:
	spin_unlock(&journal->j_state_lock);
	del_timer_sync(&journal->j_commit_timer);
	journal->j_task = NULL;
	wake_up(&journal->j_wait_done_commit);
	jbd_debug(1, "Journal thread exiting.\n");
	return 0;
}
Beispiel #17
0
static int
vsock_stream_recvmsg(struct kiocb *kiocb,
		     struct socket *sock,
		     struct msghdr *msg, size_t len, int flags)
{
	struct sock *sk;
	struct vsock_sock *vsk;
	int err;
	size_t target;
	ssize_t copied;
	long timeout;
	struct vsock_transport_recv_notify_data recv_data;

	DEFINE_WAIT(wait);

	sk = sock->sk;
	vsk = vsock_sk(sk);
	err = 0;

	lock_sock(sk);

	if (sk->sk_state != SS_CONNECTED) {
		/* Recvmsg is supposed to return 0 if a peer performs an
		 * orderly shutdown. Differentiate between that case and when a
		 * peer has not connected or a local shutdown occured with the
		 * SOCK_DONE flag.
		 */
		if (sock_flag(sk, SOCK_DONE))
			err = 0;
		else
			err = -ENOTCONN;

		goto out;
	}

	if (flags & MSG_OOB) {
		err = -EOPNOTSUPP;
		goto out;
	}

	/* We don't check peer_shutdown flag here since peer may actually shut
	 * down, but there can be data in the queue that a local socket can
	 * receive.
	 */
	if (sk->sk_shutdown & RCV_SHUTDOWN) {
		err = 0;
		goto out;
	}

	/* It is valid on Linux to pass in a zero-length receive buffer.  This
	 * is not an error.  We may as well bail out now.
	 */
	if (!len) {
		err = 0;
		goto out;
	}

	/* We must not copy less than target bytes into the user's buffer
	 * before returning successfully, so we wait for the consume queue to
	 * have that much data to consume before dequeueing.  Note that this
	 * makes it impossible to handle cases where target is greater than the
	 * queue size.
	 */
	target = sock_rcvlowat(sk, flags & MSG_WAITALL, len);
	if (target >= transport->stream_rcvhiwat(vsk)) {
		err = -ENOMEM;
		goto out;
	}
	timeout = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);
	copied = 0;

	err = transport->notify_recv_init(vsk, target, &recv_data);
	if (err < 0)
		goto out;

	prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);

	while (1) {
		s64 ready = vsock_stream_has_data(vsk);

		if (ready < 0) {
			/* Invalid queue pair content. XXX This should be
			 * changed to a connection reset in a later change.
			 */

			err = -ENOMEM;
			goto out_wait;
		} else if (ready > 0) {
			ssize_t read;

			err = transport->notify_recv_pre_dequeue(
					vsk, target, &recv_data);
			if (err < 0)
				break;

			read = transport->stream_dequeue(
					vsk, msg->msg_iov,
					len - copied, flags);
			if (read < 0) {
				err = -ENOMEM;
				break;
			}

			copied += read;

			err = transport->notify_recv_post_dequeue(
					vsk, target, read,
					!(flags & MSG_PEEK), &recv_data);
			if (err < 0)
				goto out_wait;

			if (read >= target || flags & MSG_PEEK)
				break;

			target -= read;
		} else {
			if (sk->sk_err != 0 || (sk->sk_shutdown & RCV_SHUTDOWN)
			    || (vsk->peer_shutdown & SEND_SHUTDOWN)) {
				break;
			}
			/* Don't wait for non-blocking sockets. */
			if (timeout == 0) {
				err = -EAGAIN;
				break;
			}

			err = transport->notify_recv_pre_block(
					vsk, target, &recv_data);
			if (err < 0)
				break;

			release_sock(sk);
			timeout = schedule_timeout(timeout);
			lock_sock(sk);

			if (signal_pending(current)) {
				err = sock_intr_errno(timeout);
				break;
			} else if (timeout == 0) {
				err = -EAGAIN;
				break;
			}

			prepare_to_wait(sk_sleep(sk), &wait,
					TASK_INTERRUPTIBLE);
		}
	}

	if (sk->sk_err)
		err = -sk->sk_err;
	else if (sk->sk_shutdown & RCV_SHUTDOWN)
		err = 0;

	if (copied > 0) {
		/* We only do these additional bookkeeping/notification steps
		 * if we actually copied something out of the queue pair
		 * instead of just peeking ahead.
		 */

		if (!(flags & MSG_PEEK)) {
			/* If the other side has shutdown for sending and there
			 * is nothing more to read, then modify the socket
			 * state.
			 */
			if (vsk->peer_shutdown & SEND_SHUTDOWN) {
				if (vsock_stream_has_data(vsk) <= 0) {
					sk->sk_state = SS_UNCONNECTED;
					sock_set_flag(sk, SOCK_DONE);
					sk->sk_state_change(sk);
				}
			}
		}
		err = copied;
	}

out_wait:
	finish_wait(sk_sleep(sk), &wait);
out:
	release_sock(sk);
	return err;
}
Beispiel #18
0
static ssize_t
write_rio(struct file *file, const char __user *buffer,
	  size_t count, loff_t * ppos)
{
	DEFINE_WAIT(wait);
	struct rio_usb_data *rio = &rio_instance;

	unsigned long copy_size;
	unsigned long bytes_written = 0;
	unsigned int partial;

	int result = 0;
	int maxretry;
	int errn = 0;
	int intr;

	intr = mutex_lock_interruptible(&(rio->lock));
	if (intr)
		return -EINTR;
        /* Sanity check to make sure rio is connected, powered, etc */
        if ( rio == NULL ||
             rio->present == 0 ||
             rio->rio_dev == NULL )
	{
		mutex_unlock(&(rio->lock));
		return -ENODEV;
	}



	do {
		unsigned long thistime;
		char *obuf = rio->obuf;

		thistime = copy_size =
		    (count >= OBUF_SIZE) ? OBUF_SIZE : count;
		if (copy_from_user(rio->obuf, buffer, copy_size)) {
			errn = -EFAULT;
			goto error;
		}
		maxretry = 5;
		while (thistime) {
			if (!rio->rio_dev) {
				errn = -ENODEV;
				goto error;
			}
			if (signal_pending(current)) {
				mutex_unlock(&(rio->lock));
				return bytes_written ? bytes_written : -EINTR;
			}

			result = usb_bulk_msg(rio->rio_dev,
					 usb_sndbulkpipe(rio->rio_dev, 2),
					 obuf, thistime, &partial, 5000);

			dbg("write stats: result:%d thistime:%lu partial:%u",
			     result, thistime, partial);

			if (result == -ETIMEDOUT) {	/* NAK - so hold for a while */
				if (!maxretry--) {
					errn = -ETIME;
					goto error;
				}
				prepare_to_wait(&rio->wait_q, &wait, TASK_INTERRUPTIBLE);
				schedule_timeout(NAK_TIMEOUT);
				finish_wait(&rio->wait_q, &wait);
				continue;
			} else if (!result && partial) {
				obuf += partial;
				thistime -= partial;
			} else
				break;
		};
		if (result) {
			err("Write Whoops - %x", result);
			errn = -EIO;
			goto error;
		}
		bytes_written += copy_size;
		count -= copy_size;
		buffer += copy_size;
	} while (count > 0);

	mutex_unlock(&(rio->lock));

	return bytes_written ? bytes_written : -EIO;

error:
	mutex_unlock(&(rio->lock));
	return errn;
}
Beispiel #19
0
static int
islpci_reset_if(islpci_private *priv)
{
	long remaining;
	int result = -ETIME;
	int count;

	DEFINE_WAIT(wait);
	prepare_to_wait(&priv->reset_done, &wait, TASK_UNINTERRUPTIBLE);

	/* now the last step is to reset the interface */
	isl38xx_interface_reset(priv->device_base, priv->device_host_address);
	islpci_set_state(priv, PRV_STATE_PREINIT);

        for(count = 0; count < 2 && result; count++) {
		/* The software reset acknowledge needs about 220 msec here.
		 * Be conservative and wait for up to one second. */

		remaining = schedule_timeout_uninterruptible(HZ);

		if(remaining > 0) {
			result = 0;
			break;
		}

		/* If we're here it's because our IRQ hasn't yet gone through.
		 * Retry a bit more...
		 */
		printk(KERN_ERR "%s: no 'reset complete' IRQ seen - retrying\n",
			priv->ndev->name);
	}

	finish_wait(&priv->reset_done, &wait);

	if (result) {
		printk(KERN_ERR "%s: interface reset failure\n", priv->ndev->name);
		return result;
	}

	islpci_set_state(priv, PRV_STATE_INIT);

	/* Now that the device is 100% up, let's allow
	 * for the other interrupts --
	 * NOTE: this is not *yet* true since we've only allowed the
	 * INIT interrupt on the IRQ line. We can perhaps poll
	 * the IRQ line until we know for sure the reset went through */
	isl38xx_enable_common_interrupts(priv->device_base);

	down_write(&priv->mib_sem);
	result = mgt_commit(priv);
	if (result) {
		printk(KERN_ERR "%s: interface reset failure\n", priv->ndev->name);
		up_write(&priv->mib_sem);
		return result;
	}
	up_write(&priv->mib_sem);

	islpci_set_state(priv, PRV_STATE_READY);

	printk(KERN_DEBUG "%s: interface reset complete\n", priv->ndev->name);
	return 0;
}
Beispiel #20
0
static ssize_t
read_rio(struct file *file, char __user *buffer, size_t count, loff_t * ppos)
{
	DEFINE_WAIT(wait);
	struct rio_usb_data *rio = &rio_instance;
	ssize_t read_count;
	unsigned int partial;
	int this_read;
	int result;
	int maxretry = 10;
	char *ibuf;
	int intr;

	intr = mutex_lock_interruptible(&(rio->lock));
	if (intr)
		return -EINTR;
	/* Sanity check to make sure rio is connected, powered, etc */
        if ( rio == NULL ||
             rio->present == 0 ||
             rio->rio_dev == NULL )
	{
		mutex_unlock(&(rio->lock));
		return -ENODEV;
	}

	ibuf = rio->ibuf;

	read_count = 0;


	while (count > 0) {
		if (signal_pending(current)) {
			mutex_unlock(&(rio->lock));
			return read_count ? read_count : -EINTR;
		}
		if (!rio->rio_dev) {
			mutex_unlock(&(rio->lock));
			return -ENODEV;
		}
		this_read = (count >= IBUF_SIZE) ? IBUF_SIZE : count;

		result = usb_bulk_msg(rio->rio_dev,
				      usb_rcvbulkpipe(rio->rio_dev, 1),
				      ibuf, this_read, &partial,
				      8000);

		dbg("read stats: result:%d this_read:%u partial:%u",
		       result, this_read, partial);

		if (partial) {
			count = this_read = partial;
		} else if (result == -ETIMEDOUT || result == 15) {	/* FIXME: 15 ??? */
			if (!maxretry--) {
				mutex_unlock(&(rio->lock));
				err("read_rio: maxretry timeout");
				return -ETIME;
			}
			prepare_to_wait(&rio->wait_q, &wait, TASK_INTERRUPTIBLE);
			schedule_timeout(NAK_TIMEOUT);
			finish_wait(&rio->wait_q, &wait);
			continue;
		} else if (result != -EREMOTEIO) {
			mutex_unlock(&(rio->lock));
			err("Read Whoops - result:%u partial:%u this_read:%u",
			     result, partial, this_read);
			return -EIO;
		} else {
			mutex_unlock(&(rio->lock));
			return (0);
		}

		if (this_read) {
			if (copy_to_user(buffer, ibuf, this_read)) {
				mutex_unlock(&(rio->lock));
				return -EFAULT;
			}
			count -= this_read;
			read_count += this_read;
			buffer += this_read;
		}
	}
	mutex_unlock(&(rio->lock));
	return read_count;
}
/**
 * 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);
		/* paired with rmb in mempool_free(), read comment there */
		smp_wmb();
		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;
}
Beispiel #22
0
static int svc_connect(struct socket *sock,struct sockaddr *sockaddr,
    int sockaddr_len,int flags)
{
	DEFINE_WAIT(wait);
	struct sock *sk = sock->sk;
	struct sockaddr_atmsvc *addr;
	struct atm_vcc *vcc = ATM_SD(sock);
	int error;

	DPRINTK("svc_connect %p\n",vcc);
	lock_sock(sk);
	if (sockaddr_len != sizeof(struct sockaddr_atmsvc)) {
		error = -EINVAL;
		goto out;
	}

	switch (sock->state) {
	default:
		error = -EINVAL;
		goto out;
	case SS_CONNECTED:
		error = -EISCONN;
		goto out;
	case SS_CONNECTING:
		if (test_bit(ATM_VF_WAITING, &vcc->flags)) {
			error = -EALREADY;
			goto out;
		}
		sock->state = SS_UNCONNECTED;
		if (sk->sk_err) {
			error = -sk->sk_err;
			goto out;
		}
		break;
	case SS_UNCONNECTED:
		addr = (struct sockaddr_atmsvc *) sockaddr;
		if (addr->sas_family != AF_ATMSVC) {
			error = -EAFNOSUPPORT;
			goto out;
		}
		if (!test_bit(ATM_VF_HASQOS, &vcc->flags)) {
			error = -EBADFD;
			goto out;
		}
		if (vcc->qos.txtp.traffic_class == ATM_ANYCLASS ||
		    vcc->qos.rxtp.traffic_class == ATM_ANYCLASS) {
			error = -EINVAL;
			goto out;
		}
		if (!vcc->qos.txtp.traffic_class &&
		    !vcc->qos.rxtp.traffic_class) {
			error = -EINVAL;
			goto out;
		}
		vcc->remote = *addr;
		set_bit(ATM_VF_WAITING, &vcc->flags);
		prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);
		sigd_enq(vcc,as_connect,NULL,NULL,&vcc->remote);
		if (flags & O_NONBLOCK) {
			finish_wait(sk->sk_sleep, &wait);
			sock->state = SS_CONNECTING;
			error = -EINPROGRESS;
			goto out;
		}
		error = 0;
		while (test_bit(ATM_VF_WAITING, &vcc->flags) && sigd) {
			schedule();
			if (!signal_pending(current)) {
				prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);
				continue;
			}
			DPRINTK("*ABORT*\n");
			/*
			 * This is tricky:
			 *   Kernel ---close--> Demon
			 *   Kernel <--close--- Demon
			 * or
			 *   Kernel ---close--> Demon
			 *   Kernel <--error--- Demon
			 * or
			 *   Kernel ---close--> Demon
			 *   Kernel <--okay---- Demon
			 *   Kernel <--close--- Demon
			 */
			sigd_enq(vcc,as_close,NULL,NULL,NULL);
			while (test_bit(ATM_VF_WAITING, &vcc->flags) && sigd) {
				prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);
				schedule();
			}
			if (!sk->sk_err)
				while (!test_bit(ATM_VF_RELEASED,&vcc->flags)
				    && sigd) {
					prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);
					schedule();
				}
			clear_bit(ATM_VF_REGIS,&vcc->flags);
			clear_bit(ATM_VF_RELEASED,&vcc->flags);
			clear_bit(ATM_VF_CLOSE,&vcc->flags);
			    /* we're gone now but may connect later */
			error = -EINTR;
			break;
		}
		finish_wait(sk->sk_sleep, &wait);
		if (error)
			goto out;
		if (!sigd) {
			error = -EUNATCH;
			goto out;
		}
		if (sk->sk_err) {
			error = -sk->sk_err;
			goto out;
		}
	}
/*
 * Not supported yet
 *
 * #ifndef CONFIG_SINGLE_SIGITF
 */
	vcc->qos.txtp.max_pcr = SELECT_TOP_PCR(vcc->qos.txtp);
	vcc->qos.txtp.pcr = 0;
	vcc->qos.txtp.min_pcr = 0;
/*
 * #endif
 */
	if (!(error = vcc_connect(sock, vcc->itf, vcc->vpi, vcc->vci)))
		sock->state = SS_CONNECTED;
	else
		(void) svc_disconnect(vcc);
out:
	release_sock(sk);
	return error;
}
Beispiel #23
0
static int pn_socket_connect(struct socket *sock, struct sockaddr *addr,
                             int len, int flags)
{
    struct sock *sk = sock->sk;
    struct pn_sock *pn = pn_sk(sk);
    struct sockaddr_pn *spn = (struct sockaddr_pn *)addr;
    struct task_struct *tsk = current;
    long timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
    int err;

    if (pn_socket_autobind(sock))
        return -ENOBUFS;
    if (len < sizeof(struct sockaddr_pn))
        return -EINVAL;
    if (spn->spn_family != AF_PHONET)
        return -EAFNOSUPPORT;

    lock_sock(sk);

    switch (sock->state) {
    case SS_UNCONNECTED:
        if (sk->sk_state != TCP_CLOSE) {
            err = -EISCONN;
            goto out;
        }
        break;
    case SS_CONNECTING:
        err = -EALREADY;
        goto out;
    default:
        err = -EISCONN;
        goto out;
    }

    pn->dobject = pn_sockaddr_get_object(spn);
    pn->resource = pn_sockaddr_get_resource(spn);
    sock->state = SS_CONNECTING;

    err = sk->sk_prot->connect(sk, addr, len);
    if (err) {
        sock->state = SS_UNCONNECTED;
        pn->dobject = 0;
        goto out;
    }

    while (sk->sk_state == TCP_SYN_SENT) {
        DEFINE_WAIT(wait);

        if (!timeo) {
            err = -EINPROGRESS;
            goto out;
        }
        if (signal_pending(tsk)) {
            err = sock_intr_errno(timeo);
            goto out;
        }

        prepare_to_wait_exclusive(sk_sleep(sk), &wait,
                                  TASK_INTERRUPTIBLE);
        release_sock(sk);
        timeo = schedule_timeout(timeo);
        lock_sock(sk);
        finish_wait(sk_sleep(sk), &wait);
    }

    if ((1 << sk->sk_state) & (TCPF_SYN_RECV|TCPF_ESTABLISHED))
        err = 0;
    else if (sk->sk_state == TCP_CLOSE_WAIT)
        err = -ECONNRESET;
    else
        err = -ECONNREFUSED;
    sock->state = err ? SS_UNCONNECTED : SS_CONNECTED;
out:
    release_sock(sk);
    return err;
}
Beispiel #24
0
static int svc_accept(struct socket *sock,struct socket *newsock,int flags)
{
	struct sock *sk = sock->sk;
	struct sk_buff *skb;
	struct atmsvc_msg *msg;
	struct atm_vcc *old_vcc = ATM_SD(sock);
	struct atm_vcc *new_vcc;
	int error;

	lock_sock(sk);

	error = svc_create(newsock,0);
	if (error)
		goto out;

	new_vcc = ATM_SD(newsock);

	DPRINTK("svc_accept %p -> %p\n",old_vcc,new_vcc);
	while (1) {
		DEFINE_WAIT(wait);

		prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);
		while (!(skb = skb_dequeue(&sk->sk_receive_queue)) &&
		       sigd) {
			if (test_bit(ATM_VF_RELEASED,&old_vcc->flags)) break;
			if (test_bit(ATM_VF_CLOSE,&old_vcc->flags)) {
				error = -sk->sk_err;
				break;
			}
			if (flags & O_NONBLOCK) {
				error = -EAGAIN;
				break;
			}
			release_sock(sk);
			schedule();
			lock_sock(sk);
			if (signal_pending(current)) {
				error = -ERESTARTSYS;
				break;
			}
			prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);
		}
		finish_wait(sk->sk_sleep, &wait);
		if (error)
			goto out;
		if (!skb) {
			error = -EUNATCH;
			goto out;
		}
		msg = (struct atmsvc_msg *) skb->data;
		new_vcc->qos = msg->qos;
		set_bit(ATM_VF_HASQOS,&new_vcc->flags);
		new_vcc->remote = msg->svc;
		new_vcc->local = msg->local;
		new_vcc->sap = msg->sap;
		error = vcc_connect(newsock, msg->pvc.sap_addr.itf,
				    msg->pvc.sap_addr.vpi, msg->pvc.sap_addr.vci);
		dev_kfree_skb(skb);
		sk->sk_ack_backlog--;
		if (error) {
			sigd_enq2(NULL,as_reject,old_vcc,NULL,NULL,
			    &old_vcc->qos,error);
			error = error == -EAGAIN ? -EBUSY : error;
			goto out;
		}
		/* wait should be short, so we ignore the non-blocking flag */
		set_bit(ATM_VF_WAITING, &new_vcc->flags);
		prepare_to_wait(sk_atm(new_vcc)->sk_sleep, &wait, TASK_UNINTERRUPTIBLE);
		sigd_enq(new_vcc,as_accept,old_vcc,NULL,NULL);
		while (test_bit(ATM_VF_WAITING, &new_vcc->flags) && sigd) {
			release_sock(sk);
			schedule();
			lock_sock(sk);
			prepare_to_wait(sk_atm(new_vcc)->sk_sleep, &wait, TASK_UNINTERRUPTIBLE);
		}
		finish_wait(sk_atm(new_vcc)->sk_sleep, &wait);
		if (!sigd) {
			error = -EUNATCH;
			goto out;
		}
		if (!sk_atm(new_vcc)->sk_err)
			break;
		if (sk_atm(new_vcc)->sk_err != ERESTARTSYS) {
			error = -sk_atm(new_vcc)->sk_err;
			goto out;
		}
	}
	newsock->state = SS_CONNECTED;
out:
	release_sock(sk);
	return error;
}
Beispiel #25
0
ssize_t pipe_read(struct file *filp, char __user *buff, size_t count,
	loff_t *f_pos)
{
	int retval = 0;
	struct pipe_dev *dev = filp->private_data;

	PDEBUG("%s() is invoked\n", __FUNCTION__);

	if (mutex_lock_interruptible(&dev->mutex))
		return -ERESTARTSYS;

	while (!dev->buff_len) {
		DEFINE_WAIT(wait);

		mutex_unlock(&dev->mutex);

		if (filp->f_flags & O_NONBLOCK)
			return -EAGAIN;

		PDEBUG("read: process %d(%s) is going to sleep\n",
		       current->pid, current->comm);

		prepare_to_wait(&dev->rd_queue, &wait, TASK_INTERRUPTIBLE);
		if (!dev->buff_len)
			schedule();
		finish_wait(&dev->rd_queue, &wait);

		if (signal_pending(current))
			return -ERESTARTSYS;

		if (mutex_lock_interruptible(&dev->mutex))
			return -ERESTARTSYS;
	}

	if (count > dev->buff_len - *f_pos)
		count = dev->buff_len - *f_pos;

	if (copy_to_user(buff, dev->buff + *f_pos, count)) {
		PDEBUG("copy to user error!\n");
		retval = -EFAULT;
		goto copy_error;
	}

	PDEBUG("read: f_pos=%lld, count=%lu, buff_len=%d\n",
	       *f_pos, count, dev->buff_len);

	*f_pos += count;

	// all data in the buff have been read
	if (*f_pos >= dev->buff_len) {
		dev->buff_len = 0;
		*f_pos = 0;
		PDEBUG("read: process %d(%s) awakening the writers...\n",
		       current->pid, current->comm);
		wake_up_interruptible(&dev->wr_queue);
	}

	retval = count;

copy_error:
	mutex_unlock(&dev->mutex);
	return retval;
}
Beispiel #26
0
static int vsock_stream_connect(struct socket *sock, struct sockaddr *addr,
				int addr_len, int flags)
{
	int err;
	struct sock *sk;
	struct vsock_sock *vsk;
	struct sockaddr_vm *remote_addr;
	long timeout;
	DEFINE_WAIT(wait);

	err = 0;
	sk = sock->sk;
	vsk = vsock_sk(sk);

	lock_sock(sk);

	/* XXX AF_UNSPEC should make us disconnect like AF_INET. */
	switch (sock->state) {
	case SS_CONNECTED:
		err = -EISCONN;
		goto out;
	case SS_DISCONNECTING:
		err = -EINVAL;
		goto out;
	case SS_CONNECTING:
		/* This continues on so we can move sock into the SS_CONNECTED
		 * state once the connection has completed (at which point err
		 * will be set to zero also).  Otherwise, we will either wait
		 * for the connection or return -EALREADY should this be a
		 * non-blocking call.
		 */
		err = -EALREADY;
		break;
	default:
		if ((sk->sk_state == SS_LISTEN) ||
		    vsock_addr_cast(addr, addr_len, &remote_addr) != 0) {
			err = -EINVAL;
			goto out;
		}

		/* The hypervisor and well-known contexts do not have socket
		 * endpoints.
		 */
		if (!transport->stream_allow(remote_addr->svm_cid,
					     remote_addr->svm_port)) {
			err = -ENETUNREACH;
			goto out;
		}

		/* Set the remote address that we are connecting to. */
		memcpy(&vsk->remote_addr, remote_addr,
		       sizeof(vsk->remote_addr));

		err = vsock_auto_bind(vsk);
		if (err)
			goto out;

		sk->sk_state = SS_CONNECTING;

		err = transport->connect(vsk);
		if (err < 0)
			goto out;

		/* Mark sock as connecting and set the error code to in
		 * progress in case this is a non-blocking connect.
		 */
		sock->state = SS_CONNECTING;
		err = -EINPROGRESS;
	}

	/* The receive path will handle all communication until we are able to
	 * enter the connected state.  Here we wait for the connection to be
	 * completed or a notification of an error.
	 */
	timeout = vsk->connect_timeout;
	prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);

	while (sk->sk_state != SS_CONNECTED && sk->sk_err == 0) {
		if (flags & O_NONBLOCK) {
			/* If we're not going to block, we schedule a timeout
			 * function to generate a timeout on the connection
			 * attempt, in case the peer doesn't respond in a
			 * timely manner. We hold on to the socket until the
			 * timeout fires.
			 */
			sock_hold(sk);
			INIT_DELAYED_WORK(&vsk->dwork,
					  vsock_connect_timeout);
			schedule_delayed_work(&vsk->dwork, timeout);

			/* Skip ahead to preserve error code set above. */
			goto out_wait;
		}

		release_sock(sk);
		timeout = schedule_timeout(timeout);
		lock_sock(sk);

		if (signal_pending(current)) {
			err = sock_intr_errno(timeout);
			goto out_wait_error;
		} else if (timeout == 0) {
			err = -ETIMEDOUT;
			goto out_wait_error;
		}

		prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
	}

	if (sk->sk_err) {
		err = -sk->sk_err;
		goto out_wait_error;
	} else
		err = 0;

out_wait:
	finish_wait(sk_sleep(sk), &wait);
out:
	release_sock(sk);
	return err;

out_wait_error:
	sk->sk_state = SS_UNCONNECTED;
	sock->state = SS_UNCONNECTED;
	goto out_wait;
}
Beispiel #27
0
/*
 * receive a message from an RxRPC socket
 * - we need to be careful about two or more threads calling recvmsg
 *   simultaneously
 */
int rxrpc_recvmsg(struct kiocb *iocb, struct socket *sock,
		  struct msghdr *msg, size_t len, int flags)
{
	struct rxrpc_skb_priv *sp;
	struct rxrpc_call *call = NULL, *continue_call = NULL;
	struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
	struct sk_buff *skb;
	long timeo;
	int copy, ret, ullen, offset, copied = 0;
	u32 abort_code;

	DEFINE_WAIT(wait);

	_enter(",,,%zu,%d", len, flags);

	if (flags & (MSG_OOB | MSG_TRUNC))
		return -EOPNOTSUPP;

	ullen = msg->msg_flags & MSG_CMSG_COMPAT ? 4 : sizeof(unsigned long);

	timeo = sock_rcvtimeo(&rx->sk, flags & MSG_DONTWAIT);
	msg->msg_flags |= MSG_MORE;

	lock_sock(&rx->sk);

	for (;;) {
		/* return immediately if a client socket has no outstanding
		 * calls */
		if (RB_EMPTY_ROOT(&rx->calls)) {
			if (copied)
				goto out;
			if (rx->sk.sk_state != RXRPC_SERVER_LISTENING) {
				release_sock(&rx->sk);
				if (continue_call)
					rxrpc_put_call(continue_call);
				return -ENODATA;
			}
		}

		/* get the next message on the Rx queue */
		skb = skb_peek(&rx->sk.sk_receive_queue);
		if (!skb) {
			/* nothing remains on the queue */
			if (copied &&
			    (msg->msg_flags & MSG_PEEK || timeo == 0))
				goto out;

			/* wait for a message to turn up */
			release_sock(&rx->sk);
			prepare_to_wait_exclusive(sk_sleep(&rx->sk), &wait,
						  TASK_INTERRUPTIBLE);
			ret = sock_error(&rx->sk);
			if (ret)
				goto wait_error;

			if (skb_queue_empty(&rx->sk.sk_receive_queue)) {
				if (signal_pending(current))
					goto wait_interrupted;
				timeo = schedule_timeout(timeo);
			}
			finish_wait(sk_sleep(&rx->sk), &wait);
			lock_sock(&rx->sk);
			continue;
		}

	peek_next_packet:
		sp = rxrpc_skb(skb);
		call = sp->call;
		ASSERT(call != NULL);

		_debug("next pkt %s", rxrpc_pkts[sp->hdr.type]);

		/* make sure we wait for the state to be updated in this call */
		spin_lock_bh(&call->lock);
		spin_unlock_bh(&call->lock);

		if (test_bit(RXRPC_CALL_RELEASED, &call->flags)) {
			_debug("packet from released call");
			if (skb_dequeue(&rx->sk.sk_receive_queue) != skb)
				BUG();
			rxrpc_free_skb(skb);
			continue;
		}

		/* determine whether to continue last data receive */
		if (continue_call) {
			_debug("maybe cont");
			if (call != continue_call ||
			    skb->mark != RXRPC_SKB_MARK_DATA) {
				release_sock(&rx->sk);
				rxrpc_put_call(continue_call);
				_leave(" = %d [noncont]", copied);
				return copied;
			}
		}

		rxrpc_get_call(call);

		/* copy the peer address and timestamp */
		if (!continue_call) {
			if (msg->msg_name) {
				size_t len =
					sizeof(call->conn->trans->peer->srx);
				memcpy(msg->msg_name,
				       &call->conn->trans->peer->srx, len);
				msg->msg_namelen = len;
			}
			sock_recv_ts_and_drops(msg, &rx->sk, skb);
		}

		/* receive the message */
		if (skb->mark != RXRPC_SKB_MARK_DATA)
			goto receive_non_data_message;

		_debug("recvmsg DATA #%u { %d, %d }",
		       ntohl(sp->hdr.seq), skb->len, sp->offset);

		if (!continue_call) {
			/* only set the control data once per recvmsg() */
			ret = put_cmsg(msg, SOL_RXRPC, RXRPC_USER_CALL_ID,
				       ullen, &call->user_call_ID);
			if (ret < 0)
				goto copy_error;
			ASSERT(test_bit(RXRPC_CALL_HAS_USERID, &call->flags));
		}

		ASSERTCMP(ntohl(sp->hdr.seq), >=, call->rx_data_recv);
		ASSERTCMP(ntohl(sp->hdr.seq), <=, call->rx_data_recv + 1);
		call->rx_data_recv = ntohl(sp->hdr.seq);

		ASSERTCMP(ntohl(sp->hdr.seq), >, call->rx_data_eaten);

		offset = sp->offset;
		copy = skb->len - offset;
		if (copy > len - copied)
			copy = len - copied;

		if (skb->ip_summed == CHECKSUM_UNNECESSARY) {
			ret = skb_copy_datagram_iovec(skb, offset,
						      msg->msg_iov, copy);
		} else {
			ret = skb_copy_and_csum_datagram_iovec(skb, offset,
							       msg->msg_iov);
			if (ret == -EINVAL)
				goto csum_copy_error;
		}

		if (ret < 0)
			goto copy_error;

		/* handle piecemeal consumption of data packets */
		_debug("copied %d+%d", copy, copied);

		offset += copy;
		copied += copy;

		if (!(flags & MSG_PEEK))
			sp->offset = offset;

		if (sp->offset < skb->len) {
			_debug("buffer full");
			ASSERTCMP(copied, ==, len);
			break;
		}

		/* we transferred the whole data packet */
		if (sp->hdr.flags & RXRPC_LAST_PACKET) {
			_debug("last");
			if (call->conn->out_clientflag) {
				 /* last byte of reply received */
				ret = copied;
				goto terminal_message;
			}

			/* last bit of request received */
			if (!(flags & MSG_PEEK)) {
				_debug("eat packet");
				if (skb_dequeue(&rx->sk.sk_receive_queue) !=
				    skb)
					BUG();
				rxrpc_free_skb(skb);
			}
			msg->msg_flags &= ~MSG_MORE;
			break;
		}

		/* move on to the next data message */
		_debug("next");
		if (!continue_call)
			continue_call = sp->call;
		else
			rxrpc_put_call(call);
		call = NULL;

		if (flags & MSG_PEEK) {
			_debug("peek next");
			skb = skb->next;
			if (skb == (struct sk_buff *) &rx->sk.sk_receive_queue)
				break;
			goto peek_next_packet;
		}

		_debug("eat packet");
		if (skb_dequeue(&rx->sk.sk_receive_queue) != skb)
			BUG();
		rxrpc_free_skb(skb);
	}
Beispiel #28
0
static int vsock_accept(struct socket *sock, struct socket *newsock, int flags)
{
	struct sock *listener;
	int err;
	struct sock *connected;
	struct vsock_sock *vconnected;
	long timeout;
	DEFINE_WAIT(wait);

	err = 0;
	listener = sock->sk;

	lock_sock(listener);

	if (sock->type != SOCK_STREAM) {
		err = -EOPNOTSUPP;
		goto out;
	}

	if (listener->sk_state != SS_LISTEN) {
		err = -EINVAL;
		goto out;
	}

	/* Wait for children sockets to appear; these are the new sockets
	 * created upon connection establishment.
	 */
	timeout = sock_sndtimeo(listener, flags & O_NONBLOCK);
	prepare_to_wait(sk_sleep(listener), &wait, TASK_INTERRUPTIBLE);

	while ((connected = vsock_dequeue_accept(listener)) == NULL &&
	       listener->sk_err == 0) {
		release_sock(listener);
		timeout = schedule_timeout(timeout);
		lock_sock(listener);

		if (signal_pending(current)) {
			err = sock_intr_errno(timeout);
			goto out_wait;
		} else if (timeout == 0) {
			err = -EAGAIN;
			goto out_wait;
		}

		prepare_to_wait(sk_sleep(listener), &wait, TASK_INTERRUPTIBLE);
	}

	if (listener->sk_err)
		err = -listener->sk_err;

	if (connected) {
		listener->sk_ack_backlog--;

		lock_sock(connected);
		vconnected = vsock_sk(connected);

		/* If the listener socket has received an error, then we should
		 * reject this socket and return.  Note that we simply mark the
		 * socket rejected, drop our reference, and let the cleanup
		 * function handle the cleanup; the fact that we found it in
		 * the listener's accept queue guarantees that the cleanup
		 * function hasn't run yet.
		 */
		if (err) {
			vconnected->rejected = true;
			release_sock(connected);
			sock_put(connected);
			goto out_wait;
		}

		newsock->state = SS_CONNECTED;
		sock_graft(connected, newsock);
		release_sock(connected);
		sock_put(connected);
	}

out_wait:
	finish_wait(sk_sleep(listener), &wait);
out:
	release_sock(listener);
	return err;
}
Beispiel #29
0
int vmw_fallback_wait(struct vmw_private *dev_priv,
		      bool lazy,
		      bool fifo_idle,
		      uint32_t seqno,
		      bool interruptible,
		      unsigned long timeout)
{
	struct vmw_fifo_state *fifo_state = &dev_priv->fifo;

	uint32_t count = 0;
	uint32_t signal_seq;
	int ret;
	unsigned long end_jiffies = jiffies + timeout;
	bool (*wait_condition)(struct vmw_private *, uint32_t);
	DEFINE_WAIT(__wait);

	wait_condition = (fifo_idle) ? &vmw_fifo_idle :
		&vmw_seqno_passed;

	/**
	 * Block command submission while waiting for idle.
	 */

	if (fifo_idle)
		down_read(&fifo_state->rwsem);
	signal_seq = atomic_read_unchecked(&dev_priv->marker_seq);
	ret = 0;

	for (;;) {
		prepare_to_wait(&dev_priv->fence_queue, &__wait,
				(interruptible) ?
				TASK_INTERRUPTIBLE : TASK_UNINTERRUPTIBLE);
		if (wait_condition(dev_priv, seqno))
			break;
		if (time_after_eq(jiffies, end_jiffies)) {
			DRM_ERROR("SVGA device lockup.\n");
			break;
		}
		if (lazy)
			schedule_timeout(1);
		else if ((++count & 0x0F) == 0) {
			/**
			 * FIXME: Use schedule_hr_timeout here for
			 * newer kernels and lower CPU utilization.
			 */

			__set_current_state(TASK_RUNNING);
			schedule();
			__set_current_state((interruptible) ?
					    TASK_INTERRUPTIBLE :
					    TASK_UNINTERRUPTIBLE);
		}
		if (interruptible && signal_pending(current)) {
			ret = -ERESTARTSYS;
			break;
		}
	}
	finish_wait(&dev_priv->fence_queue, &__wait);
	if (ret == 0 && fifo_idle) {
		__le32 __iomem *fifo_mem = dev_priv->mmio_virt;
		iowrite32(signal_seq, fifo_mem + SVGA_FIFO_FENCE);
	}
	wake_up_all(&dev_priv->fence_queue);
	if (fifo_idle)
		up_read(&fifo_state->rwsem);

	return ret;
}
Beispiel #30
0
static int start_this_handle(journal_t *journal, handle_t *handle,
			     gfp_t gfp_mask)
{
	transaction_t	*transaction, *new_transaction = NULL;
	tid_t		tid;
	int		needed, need_to_start;
	int		nblocks = handle->h_buffer_credits;
	unsigned long ts = jiffies;

	if (nblocks > journal->j_max_transaction_buffers) {
		printk(KERN_ERR "JBD2: %s wants too many credits (%d > %d)\n",
		       current->comm, nblocks,
		       journal->j_max_transaction_buffers);
		return -ENOSPC;
	}

alloc_transaction:
	if (!journal->j_running_transaction) {
		new_transaction = kmem_cache_alloc(transaction_cache,
						   gfp_mask | __GFP_ZERO);
		if (!new_transaction) {
			if ((gfp_mask & __GFP_FS) == 0) {
				congestion_wait(BLK_RW_ASYNC, HZ/50);
				goto alloc_transaction;
			}
			return -ENOMEM;
		}
	}

	jbd_debug(3, "New handle %p going live.\n", handle);

repeat:
	read_lock(&journal->j_state_lock);
	BUG_ON(journal->j_flags & JBD2_UNMOUNT);
	if (is_journal_aborted(journal) ||
	    (journal->j_errno != 0 && !(journal->j_flags & JBD2_ACK_ERR))) {
		read_unlock(&journal->j_state_lock);
		jbd2_journal_free_transaction(new_transaction);
		return -EROFS;
	}

	
	if (journal->j_barrier_count) {
		read_unlock(&journal->j_state_lock);
		wait_event(journal->j_wait_transaction_locked,
				journal->j_barrier_count == 0);
		goto repeat;
	}

	if (!journal->j_running_transaction) {
		read_unlock(&journal->j_state_lock);
		if (!new_transaction)
			goto alloc_transaction;
		write_lock(&journal->j_state_lock);
		if (!journal->j_running_transaction &&
		    !journal->j_barrier_count) {
			jbd2_get_transaction(journal, new_transaction);
			new_transaction = NULL;
		}
		write_unlock(&journal->j_state_lock);
		goto repeat;
	}

	transaction = journal->j_running_transaction;

	if (transaction->t_state == T_LOCKED) {
		DEFINE_WAIT(wait);

		prepare_to_wait(&journal->j_wait_transaction_locked,
					&wait, TASK_UNINTERRUPTIBLE);
		read_unlock(&journal->j_state_lock);
		schedule();
		finish_wait(&journal->j_wait_transaction_locked, &wait);
		goto repeat;
	}

	needed = atomic_add_return(nblocks,
				   &transaction->t_outstanding_credits);

	if (needed > journal->j_max_transaction_buffers) {
		DEFINE_WAIT(wait);

		jbd_debug(2, "Handle %p starting new commit...\n", handle);
		atomic_sub(nblocks, &transaction->t_outstanding_credits);
		prepare_to_wait(&journal->j_wait_transaction_locked, &wait,
				TASK_UNINTERRUPTIBLE);
		tid = transaction->t_tid;
		need_to_start = !tid_geq(journal->j_commit_request, tid);
		read_unlock(&journal->j_state_lock);
		if (need_to_start)
			jbd2_log_start_commit(journal, tid);
		schedule();
		finish_wait(&journal->j_wait_transaction_locked, &wait);
		goto repeat;
	}


	if (__jbd2_log_space_left(journal) < jbd_space_needed(journal)) {
		jbd_debug(2, "Handle %p waiting for checkpoint...\n", handle);
		atomic_sub(nblocks, &transaction->t_outstanding_credits);
		read_unlock(&journal->j_state_lock);
		write_lock(&journal->j_state_lock);
		if (__jbd2_log_space_left(journal) < jbd_space_needed(journal))
			__jbd2_log_wait_for_space(journal);
		write_unlock(&journal->j_state_lock);
		goto repeat;
	}

	update_t_max_wait(transaction, ts);
	handle->h_transaction = transaction;
	atomic_inc(&transaction->t_updates);
	atomic_inc(&transaction->t_handle_count);
	jbd_debug(4, "Handle %p given %d credits (total %d, free %d)\n",
		  handle, nblocks,
		  atomic_read(&transaction->t_outstanding_credits),
		  __jbd2_log_space_left(journal));
	read_unlock(&journal->j_state_lock);

	lock_map_acquire(&handle->h_lockdep_map);
	jbd2_journal_free_transaction(new_transaction);
	return 0;
}