Linux-2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 443 insertions, 0 deletions

diff --git a/arch/um/kernel/irq_user.c b/arch/um/kernel/irq_user.c
new file mode 100644
index 00000000000..6d6f9484b88
--- /dev/null
+++ b/arch/um/kernel/irq_user.c
@@ -0,0 +1,443 @@
+/* 
+ * Copyright (C) 2000 Jeff Dike (jdike@karaya.com)
+ * Licensed under the GPL
+ */
+
+#include <stdlib.h>
+#include <unistd.h>
+#include <errno.h>
+#include <signal.h>
+#include <string.h>
+#include <sys/poll.h>
+#include <sys/types.h>
+#include <sys/time.h>
+#include "user_util.h"
+#include "kern_util.h"
+#include "user.h"
+#include "process.h"
+#include "signal_user.h"
+#include "sigio.h"
+#include "irq_user.h"
+#include "os.h"
+
+struct irq_fd {
+	struct irq_fd *next;
+	void *id;
+	int fd;
+	int type;
+	int irq;
+	int pid;
+	int events;
+	int current_events;
+	int freed;
+};
+
+static struct irq_fd *active_fds = NULL;
+static struct irq_fd **last_irq_ptr = &active_fds;
+
+static struct pollfd *pollfds = NULL;
+static int pollfds_num = 0;
+static int pollfds_size = 0;
+
+extern int io_count, intr_count;
+
+void sigio_handler(int sig, union uml_pt_regs *regs)
+{
+	struct irq_fd *irq_fd, *next;
+	int i, n;
+
+	if(smp_sigio_handler()) return;
+	while(1){
+		n = poll(pollfds, pollfds_num, 0);
+		if(n < 0){
+			if(errno == EINTR) continue;
+			printk("sigio_handler : poll returned %d, "
+			       "errno = %d\n", n, errno);
+			break;
+		}
+		if(n == 0) break;
+
+		irq_fd = active_fds;
+		for(i = 0; i < pollfds_num; i++){
+			if(pollfds[i].revents != 0){
+				irq_fd->current_events = pollfds[i].revents;
+				pollfds[i].fd = -1;
+			}
+			irq_fd = irq_fd->next;
+		}
+
+		for(irq_fd = active_fds; irq_fd != NULL; irq_fd = next){
+			next = irq_fd->next;
+			if(irq_fd->current_events != 0){
+				irq_fd->current_events = 0;
+				do_IRQ(irq_fd->irq, regs);
+
+				/* This is here because the next irq may be
+				 * freed in the handler.  If a console goes
+				 * away, both the read and write irqs will be
+				 * freed.  After do_IRQ, ->next will point to
+				 * a good IRQ.
+				 * Irqs can't be freed inside their handlers,
+				 * so the next best thing is to have them
+				 * marked as needing freeing, so that they
+				 * can be freed here.
+				 */
+				next = irq_fd->next;
+				if(irq_fd->freed){
+					free_irq(irq_fd->irq, irq_fd->id);
+					free_irq_by_irq_and_dev(irq_fd->irq,
+								irq_fd->id);
+				}
+			}
+		}
+	}
+}
+
+int activate_ipi(int fd, int pid)
+{
+	return(os_set_fd_async(fd, pid));
+}
+
+static void maybe_sigio_broken(int fd, int type)
+{
+	if(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, size;
+
+	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 = POLLIN | POLLPRI;
+	else events = POLLOUT;
+	*new_fd = ((struct irq_fd) { .next  		= NULL,
+				     .id 		= dev_id,
+				     .fd 		= fd,
+				     .type 		= type,
+				     .irq 		= irq,
+				     .pid  		= pid,
+				     .events 		= events,
+				     .current_events 	= 0,
+				     .freed 		= 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%x, 0x%x\n", irq_fd->id, dev_id);
+			goto out_unlock;
+		}
+	}
+
+	n = pollfds_num;
+	if(n == pollfds_size){
+		while(1){
+			/* 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, we free
+			 * the buffer and try again.
+			 */
+			irq_unlock(flags);
+			size = (pollfds_num + 1) * sizeof(pollfds[0]);
+			tmp_pfd = um_kmalloc(size);
+			flags = irq_lock();
+			if(tmp_pfd == NULL)
+				goto out_unlock;
+			if(n == pollfds_size)
+				break;
+			kfree(tmp_pfd);
+		}
+		if(pollfds != NULL){
+			memcpy(tmp_pfd, pollfds,
+			       sizeof(pollfds[0]) * pollfds_size);
+			kfree(pollfds);
+		}
+		pollfds = tmp_pfd;
+		pollfds_size++;
+	}
+
+	if(type == IRQ_WRITE) 
+		fd = -1;
+
+	pollfds[pollfds_num] = ((struct pollfd) { .fd 	= fd,
+						  .events 	= events,
+						  .revents 	= 0 });
+	pollfds_num++;
+
+	*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);
+	kfree(new_fd);
+ out:
+	return(err);
+}
+
+static void free_irq_by_cb(int (*test)(struct irq_fd *, void *), void *arg)
+{
+	struct irq_fd **prev;
+	unsigned long flags;
+	int i = 0;
+
+	flags = irq_lock();
+	prev = &active_fds;
+	while(*prev != NULL){
+		if((*test)(*prev, arg)){
+			struct irq_fd *old_fd = *prev;
+			if((pollfds[i].fd != -1) && 
+			   (pollfds[i].fd != (*prev)->fd)){
+				printk("free_irq_by_cb - mismatch between "
+				       "active_fds and pollfds, fd %d vs %d\n",
+				       (*prev)->fd, pollfds[i].fd);
+				goto out;
+			}
+			memcpy(&pollfds[i], &pollfds[i + 1],
+			       (pollfds_num - i - 1) * sizeof(pollfds[0]));
+			pollfds_num--;
+			if(last_irq_ptr == &old_fd->next) 
+				last_irq_ptr = prev;
+			*prev = (*prev)->next;
+			if(old_fd->type == IRQ_WRITE) 
+				ignore_sigio_fd(old_fd->fd);
+			kfree(old_fd);
+			continue;
+		}
+		prev = &(*prev)->next;
+		i++;
+	}
+ out:
+	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;
+
+	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;
+	}
+	if((pollfds[i].fd != -1) && (pollfds[i].fd != fd)){
+		printk("find_irq_by_fd - mismatch between active_fds and "
+		       "pollfds, fd %d vs %d, need %d\n", irq->fd, 
+		       pollfds[i].fd, fd);
+		irq = NULL;
+		goto out;
+	}
+	*index_out = i;
+ out:
+	return(irq);
+}
+
+void free_irq_later(int irq, void *dev_id)
+{
+	struct irq_fd *irq_fd;
+	unsigned long flags;
+
+	flags = irq_lock();
+	for(irq_fd = active_fds; irq_fd != NULL; irq_fd = irq_fd->next){
+		if((irq_fd->irq == irq) && (irq_fd->id == dev_id))
+			break;
+	}
+	if(irq_fd == NULL){
+		printk("free_irq_later found no irq, irq = %d, "
+		       "dev_id = 0x%p\n", irq, dev_id);
+		goto out;
+	}
+	irq_fd->freed = 1;
+ out:
+	irq_unlock(flags);
+}
+
+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;
+	}
+
+	pollfds[i].fd = 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;
+	pollfds[i].fd = -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 */
+	set_handler(SIGIO, SIG_IGN, 0, -1);
+
+	return(0);
+}
+
+void forward_ipi(int fd, int pid)
+{
+	int err;
+
+	err = os_set_owner(fd, pid);
+	if(err < 0)
+		printk("forward_ipi: set_owner failed, fd = %d, me = %d, "
+		       "target = %d, err = %d\n", fd, os_getpid(), pid, -err);
+}
+
+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);
+}
+
+void init_irq_signals(int on_sigstack)
+{
+	__sighandler_t h;
+	int flags;
+
+	flags = on_sigstack ? SA_ONSTACK : 0;
+	if(timer_irq_inited) h = (__sighandler_t) alarm_handler;
+	else h = boot_timer_handler;
+
+	set_handler(SIGVTALRM, h, flags | SA_RESTART, 
+		    SIGUSR1, SIGIO, SIGWINCH, SIGALRM, -1);
+	set_handler(SIGIO, (__sighandler_t) sig_handler, flags | SA_RESTART,
+		    SIGUSR1, SIGIO, SIGWINCH, SIGALRM, SIGVTALRM, -1);
+	signal(SIGWINCH, SIG_IGN);
+}
+
+/*
+ * Overrides for Emacs so that we follow Linus's tabbing style.
+ * Emacs will notice this stuff at the end of the file and automatically
+ * adjust the settings for this buffer only.  This must remain at the end
+ * of the file.
+ * ---------------------------------------------------------------------------
+ * Local variables:
+ * c-file-style: "linux"
+ * End:
+ */