From: Paolo 'Blaisorblade' Giarrusso Chris Wedgwood Currently UML must explicitly call the UML-specific free_irq_by_irq_and_dev() for each free_irq call it's done. This is needed because ->shutdown and/or ->disable are only called when the last "action" for that irq is removed. Instead, for UML shared IRQs (UML IRQs are very often, if not always, shared), for each dev_id some setup is done, which must be cleared on the release of that fd. For instance, for each open console a new instance (i.e. new dev_id) of the same IRQ is requested(). Exactly, a fd is stored in an array (pollfds), which is after read by a host thread and passed to poll(). Each event registered by poll() triggers an interrupt. So, for each free_irq() we must remove the corresponding host fd from the table, which we do via this -release() method. In this patch we add an appropriate hook for this, and remove all uses of it by pointing the hook to the said procedure; this is safe to do since the said procedure. Also some cosmetic improvements are included. This is heavily based on some work by Chris Wedgwood, which however didn't get the patch merged for something I'd call a "misunderstanding" (the need for this patch wasn't cleanly explained, thus adding the generic hook was felt as undesirable). Signed-off-by: Paolo 'Blaisorblade' Giarrusso CC: Ingo Molnar Signed-off-by: Andrew Morton --- arch/um/drivers/line.c | 2 -- arch/um/drivers/net_kern.c | 1 - arch/um/drivers/port_kern.c | 1 - arch/um/drivers/xterm_kern.c | 1 - arch/um/kernel/irq.c | 11 +++++++---- arch/um/kernel/irq_user.c | 2 -- include/linux/irq.h | 1 + kernel/irq/manage.c | 4 ++++ 8 files changed, 12 insertions(+), 11 deletions(-) diff -puN arch/um/drivers/line.c~uml-add-and-use-generic-hw_controller_type-release arch/um/drivers/line.c --- 25/arch/um/drivers/line.c~uml-add-and-use-generic-hw_controller_type-release Fri May 27 15:42:38 2005 +++ 25-akpm/arch/um/drivers/line.c Fri May 27 15:42:39 2005 @@ -406,14 +406,12 @@ void line_disable(struct tty_struct *tty if(line->driver->read_irq == current_irq) free_irq_later(line->driver->read_irq, tty); else { - free_irq_by_irq_and_dev(line->driver->read_irq, tty); free_irq(line->driver->read_irq, tty); } if(line->driver->write_irq == current_irq) free_irq_later(line->driver->write_irq, tty); else { - free_irq_by_irq_and_dev(line->driver->write_irq, tty); free_irq(line->driver->write_irq, tty); } diff -puN arch/um/drivers/net_kern.c~uml-add-and-use-generic-hw_controller_type-release arch/um/drivers/net_kern.c --- 25/arch/um/drivers/net_kern.c~uml-add-and-use-generic-hw_controller_type-release Fri May 27 15:42:38 2005 +++ 25-akpm/arch/um/drivers/net_kern.c Fri May 27 15:42:39 2005 @@ -146,7 +146,6 @@ static int uml_net_close(struct net_devi netif_stop_queue(dev); spin_lock(&lp->lock); - free_irq_by_irq_and_dev(dev->irq, dev); free_irq(dev->irq, dev); if(lp->close != NULL) (*lp->close)(lp->fd, &lp->user); diff -puN arch/um/drivers/port_kern.c~uml-add-and-use-generic-hw_controller_type-release arch/um/drivers/port_kern.c --- 25/arch/um/drivers/port_kern.c~uml-add-and-use-generic-hw_controller_type-release Fri May 27 15:42:38 2005 +++ 25-akpm/arch/um/drivers/port_kern.c Fri May 27 15:42:39 2005 @@ -257,7 +257,6 @@ int port_wait(void *data) * connection. Then we loop here throwing out failed * connections until a good one is found. */ - free_irq_by_irq_and_dev(TELNETD_IRQ, conn); free_irq(TELNETD_IRQ, conn); if(conn->fd >= 0) break; diff -puN arch/um/drivers/xterm_kern.c~uml-add-and-use-generic-hw_controller_type-release arch/um/drivers/xterm_kern.c --- 25/arch/um/drivers/xterm_kern.c~uml-add-and-use-generic-hw_controller_type-release Fri May 27 15:42:38 2005 +++ 25-akpm/arch/um/drivers/xterm_kern.c Fri May 27 15:42:39 2005 @@ -69,7 +69,6 @@ int xterm_fd(int socket, int *pid_out) * isn't set) this will hang... */ wait_for_completion(&data->ready); - free_irq_by_irq_and_dev(XTERM_IRQ, data); free_irq(XTERM_IRQ, data); ret = data->new_fd; diff -puN arch/um/kernel/irq.c~uml-add-and-use-generic-hw_controller_type-release arch/um/kernel/irq.c --- 25/arch/um/kernel/irq.c~uml-add-and-use-generic-hw_controller_type-release Fri May 27 15:42:38 2005 +++ 25-akpm/arch/um/kernel/irq.c Fri May 27 15:42:39 2005 @@ -124,14 +124,16 @@ void irq_unlock(unsigned long flags) spin_unlock_irqrestore(&irq_spinlock, flags); } -/* presently hw_interrupt_type must define (startup || enable) && - * disable && end */ +/* hw_interrupt_type must define (startup || enable) && + * (shutdown || disable) && end */ static void dummy(unsigned int irq) { } -static struct hw_interrupt_type SIGIO_irq_type = { +/* This is used for everything else than the timer. */ +static struct hw_interrupt_type normal_irq_type = { .typename = "SIGIO", + .release = free_irq_by_irq_and_dev, .disable = dummy, .enable = dummy, .ack = dummy, @@ -140,6 +142,7 @@ static struct hw_interrupt_type SIGIO_ir static struct hw_interrupt_type SIGVTALRM_irq_type = { .typename = "SIGVTALRM", + .release = free_irq_by_irq_and_dev, .shutdown = dummy, /* never called */ .disable = dummy, .enable = dummy, @@ -160,7 +163,7 @@ void __init init_IRQ(void) irq_desc[i].status = IRQ_DISABLED; irq_desc[i].action = NULL; irq_desc[i].depth = 1; - irq_desc[i].handler = &SIGIO_irq_type; + irq_desc[i].handler = &normal_irq_type; enable_irq(i); } } diff -puN arch/um/kernel/irq_user.c~uml-add-and-use-generic-hw_controller_type-release arch/um/kernel/irq_user.c --- 25/arch/um/kernel/irq_user.c~uml-add-and-use-generic-hw_controller_type-release Fri May 27 15:42:38 2005 +++ 25-akpm/arch/um/kernel/irq_user.c Fri May 27 15:42:39 2005 @@ -85,8 +85,6 @@ void sigio_handler(int sig, union uml_pt 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); } } } diff -puN include/linux/irq.h~uml-add-and-use-generic-hw_controller_type-release include/linux/irq.h --- 25/include/linux/irq.h~uml-add-and-use-generic-hw_controller_type-release Fri May 27 15:42:38 2005 +++ 25-akpm/include/linux/irq.h Fri May 27 15:42:39 2005 @@ -47,6 +47,7 @@ struct hw_interrupt_type { void (*ack)(unsigned int irq); void (*end)(unsigned int irq); void (*set_affinity)(unsigned int irq, cpumask_t dest); + void (*release)(unsigned int irq, void *dev_id); }; typedef struct hw_interrupt_type hw_irq_controller; diff -puN kernel/irq/manage.c~uml-add-and-use-generic-hw_controller_type-release kernel/irq/manage.c --- 25/kernel/irq/manage.c~uml-add-and-use-generic-hw_controller_type-release Fri May 27 15:42:39 2005 +++ 25-akpm/kernel/irq/manage.c Fri May 27 15:42:39 2005 @@ -259,6 +259,10 @@ void free_irq(unsigned int irq, void *de /* Found it - now remove it from the list of entries */ *pp = action->next; + + if (desc->handler->release) + desc->handler->release(irq, dev_id); + if (!desc->action) { desc->status |= IRQ_DISABLED; if (desc->handler->shutdown) _