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!
diff --git a/arch/um/kernel/irq_user.c b/arch/um/kernel/irq_user.c
new file mode 100644
index 0000000..6d6f948
--- /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:
+ */