#include "irq_user.h"
#include "irq_kern.h"
#include "os.h"
+#include "sigio.h"
+#include "misc_constants.h"
/*
* Generic, controller-independent functions:
return 0;
}
+struct irq_fd *active_fds = NULL;
+static struct irq_fd **last_irq_ptr = &active_fds;
+
+extern void free_irqs(void);
+
+void sigio_handler(int sig, union uml_pt_regs *regs)
+{
+ struct irq_fd *irq_fd;
+ int n;
+
+ if(smp_sigio_handler()) return;
+ while(1){
+ n = os_waiting_for_events(active_fds);
+ if (n <= 0) {
+ if(n == -EINTR) continue;
+ else break;
+ }
+
+ for(irq_fd = active_fds; irq_fd != NULL; irq_fd = irq_fd->next){
+ if(irq_fd->current_events != 0){
+ irq_fd->current_events = 0;
+ do_IRQ(irq_fd->irq, regs);
+ }
+ }
+ }
+
+ free_irqs();
+}
+
+static void maybe_sigio_broken(int fd, int type)
+{
+ if(os_isatty(fd)){
+ if((type == IRQ_WRITE) && !pty_output_sigio){
+ write_sigio_workaround();
+ add_sigio_fd(fd, 0);
+ }
+ else if((type == IRQ_READ) && !pty_close_sigio){
+ write_sigio_workaround();
+ add_sigio_fd(fd, 1);
+ }
+ }
+}
+
+
+int activate_fd(int irq, int fd, int type, void *dev_id)
+{
+ struct pollfd *tmp_pfd;
+ struct irq_fd *new_fd, *irq_fd;
+ unsigned long flags;
+ int pid, events, err, n;
+
+ pid = os_getpid();
+ err = os_set_fd_async(fd, pid);
+ if(err < 0)
+ goto out;
+
+ new_fd = um_kmalloc(sizeof(*new_fd));
+ err = -ENOMEM;
+ if(new_fd == NULL)
+ goto out;
+
+ if(type == IRQ_READ) events = UM_POLLIN | UM_POLLPRI;
+ else events = UM_POLLOUT;
+ *new_fd = ((struct irq_fd) { .next = NULL,
+ .id = dev_id,
+ .fd = fd,
+ .type = type,
+ .irq = irq,
+ .pid = pid,
+ .events = events,
+ .current_events = 0 } );
+
+ /* Critical section - locked by a spinlock because this stuff can
+ * be changed from interrupt handlers. The stuff above is done
+ * outside the lock because it allocates memory.
+ */
+
+ /* Actually, it only looks like it can be called from interrupt
+ * context. The culprit is reactivate_fd, which calls
+ * maybe_sigio_broken, which calls write_sigio_workaround,
+ * which calls activate_fd. However, write_sigio_workaround should
+ * only be called once, at boot time. That would make it clear that
+ * this is called only from process context, and can be locked with
+ * a semaphore.
+ */
+ flags = irq_lock();
+ for(irq_fd = active_fds; irq_fd != NULL; irq_fd = irq_fd->next){
+ if((irq_fd->fd == fd) && (irq_fd->type == type)){
+ printk("Registering fd %d twice\n", fd);
+ printk("Irqs : %d, %d\n", irq_fd->irq, irq);
+ printk("Ids : 0x%p, 0x%p\n", irq_fd->id, dev_id);
+ goto out_unlock;
+ }
+ }
+
+ /*-------------*/
+ if(type == IRQ_WRITE)
+ fd = -1;
+
+ tmp_pfd = NULL;
+ n = 0;
+
+ while(1){
+ n = os_create_pollfd(fd, events, tmp_pfd, n);
+ if (n == 0)
+ break;
+
+ /* n > 0
+ * It means we couldn't put new pollfd to current pollfds
+ * and tmp_fds is NULL or too small for new pollfds array.
+ * Needed size is equal to n as minimum.
+ *
+ * Here we have to drop the lock in order to call
+ * kmalloc, which might sleep.
+ * If something else came in and changed the pollfds array
+ * so we will not be able to put new pollfd struct to pollfds
+ * then we free the buffer tmp_fds and try again.
+ */
+ irq_unlock(flags);
+ if (tmp_pfd != NULL) {
+ kfree(tmp_pfd);
+ tmp_pfd = NULL;
+ }
+
+ tmp_pfd = um_kmalloc(n);
+ if (tmp_pfd == NULL)
+ goto out_kfree;
+
+ flags = irq_lock();
+ }
+ /*-------------*/
+
+ *last_irq_ptr = new_fd;
+ last_irq_ptr = &new_fd->next;
+
+ irq_unlock(flags);
+
+ /* This calls activate_fd, so it has to be outside the critical
+ * section.
+ */
+ maybe_sigio_broken(fd, type);
+
+ return(0);
+
+ out_unlock:
+ irq_unlock(flags);
+ out_kfree:
+ kfree(new_fd);
+ out:
+ return(err);
+}
+
+static void free_irq_by_cb(int (*test)(struct irq_fd *, void *), void *arg)
+{
+ unsigned long flags;
+
+ flags = irq_lock();
+ os_free_irq_by_cb(test, arg, active_fds, &last_irq_ptr);
+ irq_unlock(flags);
+}
+
+struct irq_and_dev {
+ int irq;
+ void *dev;
+};
+
+static int same_irq_and_dev(struct irq_fd *irq, void *d)
+{
+ struct irq_and_dev *data = d;
+
+ return((irq->irq == data->irq) && (irq->id == data->dev));
+}
+
+void free_irq_by_irq_and_dev(unsigned int irq, void *dev)
+{
+ struct irq_and_dev data = ((struct irq_and_dev) { .irq = irq,
+ .dev = dev });
+
+ free_irq_by_cb(same_irq_and_dev, &data);
+}
+
+static int same_fd(struct irq_fd *irq, void *fd)
+{
+ return(irq->fd == *((int *) fd));
+}
+
+void free_irq_by_fd(int fd)
+{
+ free_irq_by_cb(same_fd, &fd);
+}
+
+static struct irq_fd *find_irq_by_fd(int fd, int irqnum, int *index_out)
+{
+ struct irq_fd *irq;
+ int i = 0;
+ int fdi;
+
+ for(irq=active_fds; irq != NULL; irq = irq->next){
+ if((irq->fd == fd) && (irq->irq == irqnum)) break;
+ i++;
+ }
+ if(irq == NULL){
+ printk("find_irq_by_fd doesn't have descriptor %d\n", fd);
+ goto out;
+ }
+ fdi = os_get_pollfd(i);
+ if((fdi != -1) && (fdi != fd)){
+ printk("find_irq_by_fd - mismatch between active_fds and "
+ "pollfds, fd %d vs %d, need %d\n", irq->fd,
+ fdi, fd);
+ irq = NULL;
+ goto out;
+ }
+ *index_out = i;
+ out:
+ return(irq);
+}
+
+void reactivate_fd(int fd, int irqnum)
+{
+ struct irq_fd *irq;
+ unsigned long flags;
+ int i;
+
+ flags = irq_lock();
+ irq = find_irq_by_fd(fd, irqnum, &i);
+ if(irq == NULL){
+ irq_unlock(flags);
+ return;
+ }
+ os_set_pollfd(i, irq->fd);
+ irq_unlock(flags);
+
+ /* This calls activate_fd, so it has to be outside the critical
+ * section.
+ */
+ maybe_sigio_broken(fd, irq->type);
+}
+
+void deactivate_fd(int fd, int irqnum)
+{
+ struct irq_fd *irq;
+ unsigned long flags;
+ int i;
+
+ flags = irq_lock();
+ irq = find_irq_by_fd(fd, irqnum, &i);
+ if(irq == NULL)
+ goto out;
+ os_set_pollfd(i, -1);
+ out:
+ irq_unlock(flags);
+}
+
+int deactivate_all_fds(void)
+{
+ struct irq_fd *irq;
+ int err;
+
+ for(irq=active_fds;irq != NULL;irq = irq->next){
+ err = os_clear_fd_async(irq->fd);
+ if(err)
+ return(err);
+ }
+ /* If there is a signal already queued, after unblocking ignore it */
+ os_set_ioignore();
+
+ return(0);
+}
+
+void forward_interrupts(int pid)
+{
+ struct irq_fd *irq;
+ unsigned long flags;
+ int err;
+
+ flags = irq_lock();
+ for(irq=active_fds;irq != NULL;irq = irq->next){
+ err = os_set_owner(irq->fd, pid);
+ if(err < 0){
+ /* XXX Just remove the irq rather than
+ * print out an infinite stream of these
+ */
+ printk("Failed to forward %d to pid %d, err = %d\n",
+ irq->fd, pid, -err);
+ }
+
+ irq->pid = pid;
+ }
+ irq_unlock(flags);
+}
+
/*
* do_IRQ handles all normal device IRQ's (the special
* SMP cross-CPU interrupts have their own specific
projects / linux-2.6-omap-h63xx.git / blobdiff