linux/arch/um/drivers/chan_kern.c

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[PATCH] uml: Simplify console opening/closing and irq registration This patch simplifies the opening and closing of host console devices and the registration and deregistration of IRQs. The intent is to make it obvious that an IRQ can't exist without an open file descriptor. chan_enable will now open the channel, and when both opening and IRQ registration are desired, this should be used. Opening only is done for the initial console, so that interface still needs to exist. The free_irqs_later interface is now gone. It was intended to avoid freeing an IRQ while it was being processed. It did this, but it didn't eliminate the possiblity of free_irq being called from an interrupt, which is bad. In its place is a list of irqs to be freed, which is processed by the signal handler just before exiting. close_one_chan now disables irqs. When a host device disappears, it is just closed, and that disables IRQs. The device id registered with the IRQ is now the chan structure, not the tty. This is because the interrupt arrives on a descriptor associated with the channel. This caused equivalent changes in the arguments to line_timer_cb. line_disable is gone since it is not used any more. The count field in the line structure is gone. tty->count is used instead. The complicated logic in sigio_handler with freeing IRQs when necessary and making sure its idea of the next irq is correct is now much simpler. The irq list can't be rearranged underneath it, so it is now a simple list walk. Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:18:57 +00:00
/*
* Copyright (C) 2000 - 2007 Jeff Dike (jdike@{linux.intel,addtoit}.com)
* Licensed under the GPL
*/
#include <linux/slab.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
#include "chan.h"
#include "os.h"
#include "irq_kern.h"
#ifdef CONFIG_NOCONFIG_CHAN
static void *not_configged_init(char *str, int device,
const struct chan_opts *opts)
{
printk(KERN_ERR "Using a channel type which is configured out of "
"UML\n");
return NULL;
}
static int not_configged_open(int input, int output, int primary, void *data,
char **dev_out)
{
printk(KERN_ERR "Using a channel type which is configured out of "
"UML\n");
return -ENODEV;
}
static void not_configged_close(int fd, void *data)
{
printk(KERN_ERR "Using a channel type which is configured out of "
"UML\n");
}
static int not_configged_read(int fd, char *c_out, void *data)
{
printk(KERN_ERR "Using a channel type which is configured out of "
"UML\n");
return -EIO;
}
static int not_configged_write(int fd, const char *buf, int len, void *data)
{
printk(KERN_ERR "Using a channel type which is configured out of "
"UML\n");
return -EIO;
}
static int not_configged_console_write(int fd, const char *buf, int len)
{
printk(KERN_ERR "Using a channel type which is configured out of "
"UML\n");
return -EIO;
}
static int not_configged_window_size(int fd, void *data, unsigned short *rows,
unsigned short *cols)
{
printk(KERN_ERR "Using a channel type which is configured out of "
"UML\n");
return -ENODEV;
}
static void not_configged_free(void *data)
{
printk(KERN_ERR "Using a channel type which is configured out of "
"UML\n");
}
static const struct chan_ops not_configged_ops = {
.init = not_configged_init,
.open = not_configged_open,
.close = not_configged_close,
.read = not_configged_read,
.write = not_configged_write,
.console_write = not_configged_console_write,
.window_size = not_configged_window_size,
.free = not_configged_free,
.winch = 0,
};
#endif /* CONFIG_NOCONFIG_CHAN */
static void tty_receive_char(struct tty_struct *tty, char ch)
{
if (tty == NULL)
return;
if (I_IXON(tty) && !I_IXOFF(tty) && !tty->raw) {
if (ch == STOP_CHAR(tty)) {
stop_tty(tty);
return;
}
else if (ch == START_CHAR(tty)) {
start_tty(tty);
return;
}
}
tty_insert_flip_char(tty, ch, TTY_NORMAL);
}
static int open_one_chan(struct chan *chan)
{
int fd, err;
if (chan->opened)
return 0;
if (chan->ops->open == NULL)
fd = 0;
else fd = (*chan->ops->open)(chan->input, chan->output, chan->primary,
chan->data, &chan->dev);
if (fd < 0)
return fd;
err = os_set_fd_block(fd, 0);
if (err) {
(*chan->ops->close)(fd, chan->data);
return err;
}
chan->fd = fd;
chan->opened = 1;
return 0;
}
static int open_chan(struct list_head *chans)
{
struct list_head *ele;
struct chan *chan;
int ret, err = 0;
list_for_each(ele, chans) {
chan = list_entry(ele, struct chan, list);
ret = open_one_chan(chan);
if (chan->primary)
err = ret;
}
return err;
}
void chan_enable_winch(struct chan *chan, struct tty_struct *tty)
{
if (chan && chan->primary && chan->ops->winch)
register_winch(chan->fd, tty);
}
static void line_timer_cb(struct work_struct *work)
{
struct line *line = container_of(work, struct line, task.work);
if (!line->throttled)
chan_interrupt(line, line->tty, line->driver->read_irq);
}
int enable_chan(struct line *line)
{
struct list_head *ele;
struct chan *chan;
int err;
INIT_DELAYED_WORK(&line->task, line_timer_cb);
list_for_each(ele, &line->chan_list) {
chan = list_entry(ele, struct chan, list);
err = open_one_chan(chan);
if (err) {
if (chan->primary)
goto out_close;
[PATCH] uml: Simplify console opening/closing and irq registration This patch simplifies the opening and closing of host console devices and the registration and deregistration of IRQs. The intent is to make it obvious that an IRQ can't exist without an open file descriptor. chan_enable will now open the channel, and when both opening and IRQ registration are desired, this should be used. Opening only is done for the initial console, so that interface still needs to exist. The free_irqs_later interface is now gone. It was intended to avoid freeing an IRQ while it was being processed. It did this, but it didn't eliminate the possiblity of free_irq being called from an interrupt, which is bad. In its place is a list of irqs to be freed, which is processed by the signal handler just before exiting. close_one_chan now disables irqs. When a host device disappears, it is just closed, and that disables IRQs. The device id registered with the IRQ is now the chan structure, not the tty. This is because the interrupt arrives on a descriptor associated with the channel. This caused equivalent changes in the arguments to line_timer_cb. line_disable is gone since it is not used any more. The count field in the line structure is gone. tty->count is used instead. The complicated logic in sigio_handler with freeing IRQs when necessary and making sure its idea of the next irq is correct is now much simpler. The irq list can't be rearranged underneath it, so it is now a simple list walk. Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:18:57 +00:00
continue;
}
[PATCH] uml: Simplify console opening/closing and irq registration This patch simplifies the opening and closing of host console devices and the registration and deregistration of IRQs. The intent is to make it obvious that an IRQ can't exist without an open file descriptor. chan_enable will now open the channel, and when both opening and IRQ registration are desired, this should be used. Opening only is done for the initial console, so that interface still needs to exist. The free_irqs_later interface is now gone. It was intended to avoid freeing an IRQ while it was being processed. It did this, but it didn't eliminate the possiblity of free_irq being called from an interrupt, which is bad. In its place is a list of irqs to be freed, which is processed by the signal handler just before exiting. close_one_chan now disables irqs. When a host device disappears, it is just closed, and that disables IRQs. The device id registered with the IRQ is now the chan structure, not the tty. This is because the interrupt arrives on a descriptor associated with the channel. This caused equivalent changes in the arguments to line_timer_cb. line_disable is gone since it is not used any more. The count field in the line structure is gone. tty->count is used instead. The complicated logic in sigio_handler with freeing IRQs when necessary and making sure its idea of the next irq is correct is now much simpler. The irq list can't be rearranged underneath it, so it is now a simple list walk. Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:18:57 +00:00
if (chan->enabled)
[PATCH] uml: Simplify console opening/closing and irq registration This patch simplifies the opening and closing of host console devices and the registration and deregistration of IRQs. The intent is to make it obvious that an IRQ can't exist without an open file descriptor. chan_enable will now open the channel, and when both opening and IRQ registration are desired, this should be used. Opening only is done for the initial console, so that interface still needs to exist. The free_irqs_later interface is now gone. It was intended to avoid freeing an IRQ while it was being processed. It did this, but it didn't eliminate the possiblity of free_irq being called from an interrupt, which is bad. In its place is a list of irqs to be freed, which is processed by the signal handler just before exiting. close_one_chan now disables irqs. When a host device disappears, it is just closed, and that disables IRQs. The device id registered with the IRQ is now the chan structure, not the tty. This is because the interrupt arrives on a descriptor associated with the channel. This caused equivalent changes in the arguments to line_timer_cb. line_disable is gone since it is not used any more. The count field in the line structure is gone. tty->count is used instead. The complicated logic in sigio_handler with freeing IRQs when necessary and making sure its idea of the next irq is correct is now much simpler. The irq list can't be rearranged underneath it, so it is now a simple list walk. Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:18:57 +00:00
continue;
err = line_setup_irq(chan->fd, chan->input, chan->output, line,
chan);
if (err)
goto out_close;
[PATCH] uml: Simplify console opening/closing and irq registration This patch simplifies the opening and closing of host console devices and the registration and deregistration of IRQs. The intent is to make it obvious that an IRQ can't exist without an open file descriptor. chan_enable will now open the channel, and when both opening and IRQ registration are desired, this should be used. Opening only is done for the initial console, so that interface still needs to exist. The free_irqs_later interface is now gone. It was intended to avoid freeing an IRQ while it was being processed. It did this, but it didn't eliminate the possiblity of free_irq being called from an interrupt, which is bad. In its place is a list of irqs to be freed, which is processed by the signal handler just before exiting. close_one_chan now disables irqs. When a host device disappears, it is just closed, and that disables IRQs. The device id registered with the IRQ is now the chan structure, not the tty. This is because the interrupt arrives on a descriptor associated with the channel. This caused equivalent changes in the arguments to line_timer_cb. line_disable is gone since it is not used any more. The count field in the line structure is gone. tty->count is used instead. The complicated logic in sigio_handler with freeing IRQs when necessary and making sure its idea of the next irq is correct is now much simpler. The irq list can't be rearranged underneath it, so it is now a simple list walk. Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:18:57 +00:00
chan->enabled = 1;
}
return 0;
out_close:
close_chan(line);
return err;
[PATCH] uml: Simplify console opening/closing and irq registration This patch simplifies the opening and closing of host console devices and the registration and deregistration of IRQs. The intent is to make it obvious that an IRQ can't exist without an open file descriptor. chan_enable will now open the channel, and when both opening and IRQ registration are desired, this should be used. Opening only is done for the initial console, so that interface still needs to exist. The free_irqs_later interface is now gone. It was intended to avoid freeing an IRQ while it was being processed. It did this, but it didn't eliminate the possiblity of free_irq being called from an interrupt, which is bad. In its place is a list of irqs to be freed, which is processed by the signal handler just before exiting. close_one_chan now disables irqs. When a host device disappears, it is just closed, and that disables IRQs. The device id registered with the IRQ is now the chan structure, not the tty. This is because the interrupt arrives on a descriptor associated with the channel. This caused equivalent changes in the arguments to line_timer_cb. line_disable is gone since it is not used any more. The count field in the line structure is gone. tty->count is used instead. The complicated logic in sigio_handler with freeing IRQs when necessary and making sure its idea of the next irq is correct is now much simpler. The irq list can't be rearranged underneath it, so it is now a simple list walk. Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:18:57 +00:00
}
/* Items are added in IRQ context, when free_irq can't be called, and
* removed in process context, when it can.
* This handles interrupt sources which disappear, and which need to
* be permanently disabled. This is discovered in IRQ context, but
* the freeing of the IRQ must be done later.
*/
static DEFINE_SPINLOCK(irqs_to_free_lock);
[PATCH] uml: Simplify console opening/closing and irq registration This patch simplifies the opening and closing of host console devices and the registration and deregistration of IRQs. The intent is to make it obvious that an IRQ can't exist without an open file descriptor. chan_enable will now open the channel, and when both opening and IRQ registration are desired, this should be used. Opening only is done for the initial console, so that interface still needs to exist. The free_irqs_later interface is now gone. It was intended to avoid freeing an IRQ while it was being processed. It did this, but it didn't eliminate the possiblity of free_irq being called from an interrupt, which is bad. In its place is a list of irqs to be freed, which is processed by the signal handler just before exiting. close_one_chan now disables irqs. When a host device disappears, it is just closed, and that disables IRQs. The device id registered with the IRQ is now the chan structure, not the tty. This is because the interrupt arrives on a descriptor associated with the channel. This caused equivalent changes in the arguments to line_timer_cb. line_disable is gone since it is not used any more. The count field in the line structure is gone. tty->count is used instead. The complicated logic in sigio_handler with freeing IRQs when necessary and making sure its idea of the next irq is correct is now much simpler. The irq list can't be rearranged underneath it, so it is now a simple list walk. Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:18:57 +00:00
static LIST_HEAD(irqs_to_free);
void free_irqs(void)
{
struct chan *chan;
LIST_HEAD(list);
struct list_head *ele;
unsigned long flags;
spin_lock_irqsave(&irqs_to_free_lock, flags);
list_splice_init(&irqs_to_free, &list);
spin_unlock_irqrestore(&irqs_to_free_lock, flags);
[PATCH] uml: Simplify console opening/closing and irq registration This patch simplifies the opening and closing of host console devices and the registration and deregistration of IRQs. The intent is to make it obvious that an IRQ can't exist without an open file descriptor. chan_enable will now open the channel, and when both opening and IRQ registration are desired, this should be used. Opening only is done for the initial console, so that interface still needs to exist. The free_irqs_later interface is now gone. It was intended to avoid freeing an IRQ while it was being processed. It did this, but it didn't eliminate the possiblity of free_irq being called from an interrupt, which is bad. In its place is a list of irqs to be freed, which is processed by the signal handler just before exiting. close_one_chan now disables irqs. When a host device disappears, it is just closed, and that disables IRQs. The device id registered with the IRQ is now the chan structure, not the tty. This is because the interrupt arrives on a descriptor associated with the channel. This caused equivalent changes in the arguments to line_timer_cb. line_disable is gone since it is not used any more. The count field in the line structure is gone. tty->count is used instead. The complicated logic in sigio_handler with freeing IRQs when necessary and making sure its idea of the next irq is correct is now much simpler. The irq list can't be rearranged underneath it, so it is now a simple list walk. Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:18:57 +00:00
list_for_each(ele, &list) {
chan = list_entry(ele, struct chan, free_list);
[PATCH] uml: Simplify console opening/closing and irq registration This patch simplifies the opening and closing of host console devices and the registration and deregistration of IRQs. The intent is to make it obvious that an IRQ can't exist without an open file descriptor. chan_enable will now open the channel, and when both opening and IRQ registration are desired, this should be used. Opening only is done for the initial console, so that interface still needs to exist. The free_irqs_later interface is now gone. It was intended to avoid freeing an IRQ while it was being processed. It did this, but it didn't eliminate the possiblity of free_irq being called from an interrupt, which is bad. In its place is a list of irqs to be freed, which is processed by the signal handler just before exiting. close_one_chan now disables irqs. When a host device disappears, it is just closed, and that disables IRQs. The device id registered with the IRQ is now the chan structure, not the tty. This is because the interrupt arrives on a descriptor associated with the channel. This caused equivalent changes in the arguments to line_timer_cb. line_disable is gone since it is not used any more. The count field in the line structure is gone. tty->count is used instead. The complicated logic in sigio_handler with freeing IRQs when necessary and making sure its idea of the next irq is correct is now much simpler. The irq list can't be rearranged underneath it, so it is now a simple list walk. Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:18:57 +00:00
um: call free_irq() only on enabled channels When I use OpenSUSE-11.2 on UML (> 2.6.25) I get lots of such errors: Registering fd 1 twice Irqs : 3, 3 Ids : 0x09cb41a0, 0x09cb4120 ------------[ cut here ]------------ WARNING: at kernel/irq/manage.c:896 __free_irq+0x79/0x11a() Trying to free already-free IRQ 3 Modules linked in: 09dadc6c: [<081b2edb>] dump_stack+0x1c/0x20 09dadc84: [<080716da>] warn_slowpath_common+0x49/0x77 09dadc9c: [<08071772>] warn_slowpath_fmt+0x26/0x2a 09dadcb4: [<08094e08>] __free_irq+0x79/0x11a 09dadce4: [<08094ed6>] free_irq+0x2d/0x49 09dadcf4: [<0805b4bc>] close_one_chan+0x70/0x9c 09dadd0c: [<0805b833>] close_chan+0x17/0x22 09dadd1c: [<0805bdda>] enable_chan+0x70/0x7c 09dadd3c: [<0805cbb7>] line_open+0x34/0x9f 09dadd54: [<0805b21e>] con_open+0x13/0x35 09dadd6c: [<0814dc89>] tty_open+0x285/0x384 09dadda0: [<080b754e>] chrdev_open+0xe0/0xf9 09daddc0: [<080b3fb2>] __dentry_open+0xf3/0x1e2 09dadde4: [<080b4142>] nameidata_to_filp+0x35/0x49 09daddfc: [<080bd270>] do_last+0x409/0x50e 09dade28: [<080bea04>] do_filp_open+0x175/0x446 09dadecc: [<080b3d89>] do_sys_open+0x4a/0x128 09dadf04: [<080b3ea2>] sys_open+0x19/0x21 09dadf28: [<0805ab5a>] handle_syscall+0x7a/0x98 09dadf78: [<08068441>] userspace+0x2c9/0x370 09dadfe0: [<08058bb3>] fork_handler+0x53/0x5b 09dadffc: [<00766564>] 0x766564 ---[ end trace 9ebc1094aaf4bded ]--- This patch fixes the issue. Signed-off-by: Richard Weinberger <richard@nod.at> Cc: Jeff Dike <jdike@addtoit.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-10 00:20:14 +00:00
if (chan->input && chan->enabled)
um_free_irq(chan->line->driver->read_irq, chan);
um: call free_irq() only on enabled channels When I use OpenSUSE-11.2 on UML (> 2.6.25) I get lots of such errors: Registering fd 1 twice Irqs : 3, 3 Ids : 0x09cb41a0, 0x09cb4120 ------------[ cut here ]------------ WARNING: at kernel/irq/manage.c:896 __free_irq+0x79/0x11a() Trying to free already-free IRQ 3 Modules linked in: 09dadc6c: [<081b2edb>] dump_stack+0x1c/0x20 09dadc84: [<080716da>] warn_slowpath_common+0x49/0x77 09dadc9c: [<08071772>] warn_slowpath_fmt+0x26/0x2a 09dadcb4: [<08094e08>] __free_irq+0x79/0x11a 09dadce4: [<08094ed6>] free_irq+0x2d/0x49 09dadcf4: [<0805b4bc>] close_one_chan+0x70/0x9c 09dadd0c: [<0805b833>] close_chan+0x17/0x22 09dadd1c: [<0805bdda>] enable_chan+0x70/0x7c 09dadd3c: [<0805cbb7>] line_open+0x34/0x9f 09dadd54: [<0805b21e>] con_open+0x13/0x35 09dadd6c: [<0814dc89>] tty_open+0x285/0x384 09dadda0: [<080b754e>] chrdev_open+0xe0/0xf9 09daddc0: [<080b3fb2>] __dentry_open+0xf3/0x1e2 09dadde4: [<080b4142>] nameidata_to_filp+0x35/0x49 09daddfc: [<080bd270>] do_last+0x409/0x50e 09dade28: [<080bea04>] do_filp_open+0x175/0x446 09dadecc: [<080b3d89>] do_sys_open+0x4a/0x128 09dadf04: [<080b3ea2>] sys_open+0x19/0x21 09dadf28: [<0805ab5a>] handle_syscall+0x7a/0x98 09dadf78: [<08068441>] userspace+0x2c9/0x370 09dadfe0: [<08058bb3>] fork_handler+0x53/0x5b 09dadffc: [<00766564>] 0x766564 ---[ end trace 9ebc1094aaf4bded ]--- This patch fixes the issue. Signed-off-by: Richard Weinberger <richard@nod.at> Cc: Jeff Dike <jdike@addtoit.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-10 00:20:14 +00:00
if (chan->output && chan->enabled)
um_free_irq(chan->line->driver->write_irq, chan);
[PATCH] uml: Simplify console opening/closing and irq registration This patch simplifies the opening and closing of host console devices and the registration and deregistration of IRQs. The intent is to make it obvious that an IRQ can't exist without an open file descriptor. chan_enable will now open the channel, and when both opening and IRQ registration are desired, this should be used. Opening only is done for the initial console, so that interface still needs to exist. The free_irqs_later interface is now gone. It was intended to avoid freeing an IRQ while it was being processed. It did this, but it didn't eliminate the possiblity of free_irq being called from an interrupt, which is bad. In its place is a list of irqs to be freed, which is processed by the signal handler just before exiting. close_one_chan now disables irqs. When a host device disappears, it is just closed, and that disables IRQs. The device id registered with the IRQ is now the chan structure, not the tty. This is because the interrupt arrives on a descriptor associated with the channel. This caused equivalent changes in the arguments to line_timer_cb. line_disable is gone since it is not used any more. The count field in the line structure is gone. tty->count is used instead. The complicated logic in sigio_handler with freeing IRQs when necessary and making sure its idea of the next irq is correct is now much simpler. The irq list can't be rearranged underneath it, so it is now a simple list walk. Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:18:57 +00:00
chan->enabled = 0;
}
}
static void close_one_chan(struct chan *chan, int delay_free_irq)
{
unsigned long flags;
if (!chan->opened)
[PATCH] uml: Simplify console opening/closing and irq registration This patch simplifies the opening and closing of host console devices and the registration and deregistration of IRQs. The intent is to make it obvious that an IRQ can't exist without an open file descriptor. chan_enable will now open the channel, and when both opening and IRQ registration are desired, this should be used. Opening only is done for the initial console, so that interface still needs to exist. The free_irqs_later interface is now gone. It was intended to avoid freeing an IRQ while it was being processed. It did this, but it didn't eliminate the possiblity of free_irq being called from an interrupt, which is bad. In its place is a list of irqs to be freed, which is processed by the signal handler just before exiting. close_one_chan now disables irqs. When a host device disappears, it is just closed, and that disables IRQs. The device id registered with the IRQ is now the chan structure, not the tty. This is because the interrupt arrives on a descriptor associated with the channel. This caused equivalent changes in the arguments to line_timer_cb. line_disable is gone since it is not used any more. The count field in the line structure is gone. tty->count is used instead. The complicated logic in sigio_handler with freeing IRQs when necessary and making sure its idea of the next irq is correct is now much simpler. The irq list can't be rearranged underneath it, so it is now a simple list walk. Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:18:57 +00:00
return;
if (delay_free_irq) {
spin_lock_irqsave(&irqs_to_free_lock, flags);
[PATCH] uml: Simplify console opening/closing and irq registration This patch simplifies the opening and closing of host console devices and the registration and deregistration of IRQs. The intent is to make it obvious that an IRQ can't exist without an open file descriptor. chan_enable will now open the channel, and when both opening and IRQ registration are desired, this should be used. Opening only is done for the initial console, so that interface still needs to exist. The free_irqs_later interface is now gone. It was intended to avoid freeing an IRQ while it was being processed. It did this, but it didn't eliminate the possiblity of free_irq being called from an interrupt, which is bad. In its place is a list of irqs to be freed, which is processed by the signal handler just before exiting. close_one_chan now disables irqs. When a host device disappears, it is just closed, and that disables IRQs. The device id registered with the IRQ is now the chan structure, not the tty. This is because the interrupt arrives on a descriptor associated with the channel. This caused equivalent changes in the arguments to line_timer_cb. line_disable is gone since it is not used any more. The count field in the line structure is gone. tty->count is used instead. The complicated logic in sigio_handler with freeing IRQs when necessary and making sure its idea of the next irq is correct is now much simpler. The irq list can't be rearranged underneath it, so it is now a simple list walk. Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:18:57 +00:00
list_add(&chan->free_list, &irqs_to_free);
spin_unlock_irqrestore(&irqs_to_free_lock, flags);
[PATCH] uml: Simplify console opening/closing and irq registration This patch simplifies the opening and closing of host console devices and the registration and deregistration of IRQs. The intent is to make it obvious that an IRQ can't exist without an open file descriptor. chan_enable will now open the channel, and when both opening and IRQ registration are desired, this should be used. Opening only is done for the initial console, so that interface still needs to exist. The free_irqs_later interface is now gone. It was intended to avoid freeing an IRQ while it was being processed. It did this, but it didn't eliminate the possiblity of free_irq being called from an interrupt, which is bad. In its place is a list of irqs to be freed, which is processed by the signal handler just before exiting. close_one_chan now disables irqs. When a host device disappears, it is just closed, and that disables IRQs. The device id registered with the IRQ is now the chan structure, not the tty. This is because the interrupt arrives on a descriptor associated with the channel. This caused equivalent changes in the arguments to line_timer_cb. line_disable is gone since it is not used any more. The count field in the line structure is gone. tty->count is used instead. The complicated logic in sigio_handler with freeing IRQs when necessary and making sure its idea of the next irq is correct is now much simpler. The irq list can't be rearranged underneath it, so it is now a simple list walk. Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:18:57 +00:00
}
else {
um: call free_irq() only on enabled channels When I use OpenSUSE-11.2 on UML (> 2.6.25) I get lots of such errors: Registering fd 1 twice Irqs : 3, 3 Ids : 0x09cb41a0, 0x09cb4120 ------------[ cut here ]------------ WARNING: at kernel/irq/manage.c:896 __free_irq+0x79/0x11a() Trying to free already-free IRQ 3 Modules linked in: 09dadc6c: [<081b2edb>] dump_stack+0x1c/0x20 09dadc84: [<080716da>] warn_slowpath_common+0x49/0x77 09dadc9c: [<08071772>] warn_slowpath_fmt+0x26/0x2a 09dadcb4: [<08094e08>] __free_irq+0x79/0x11a 09dadce4: [<08094ed6>] free_irq+0x2d/0x49 09dadcf4: [<0805b4bc>] close_one_chan+0x70/0x9c 09dadd0c: [<0805b833>] close_chan+0x17/0x22 09dadd1c: [<0805bdda>] enable_chan+0x70/0x7c 09dadd3c: [<0805cbb7>] line_open+0x34/0x9f 09dadd54: [<0805b21e>] con_open+0x13/0x35 09dadd6c: [<0814dc89>] tty_open+0x285/0x384 09dadda0: [<080b754e>] chrdev_open+0xe0/0xf9 09daddc0: [<080b3fb2>] __dentry_open+0xf3/0x1e2 09dadde4: [<080b4142>] nameidata_to_filp+0x35/0x49 09daddfc: [<080bd270>] do_last+0x409/0x50e 09dade28: [<080bea04>] do_filp_open+0x175/0x446 09dadecc: [<080b3d89>] do_sys_open+0x4a/0x128 09dadf04: [<080b3ea2>] sys_open+0x19/0x21 09dadf28: [<0805ab5a>] handle_syscall+0x7a/0x98 09dadf78: [<08068441>] userspace+0x2c9/0x370 09dadfe0: [<08058bb3>] fork_handler+0x53/0x5b 09dadffc: [<00766564>] 0x766564 ---[ end trace 9ebc1094aaf4bded ]--- This patch fixes the issue. Signed-off-by: Richard Weinberger <richard@nod.at> Cc: Jeff Dike <jdike@addtoit.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-10 00:20:14 +00:00
if (chan->input && chan->enabled)
um_free_irq(chan->line->driver->read_irq, chan);
um: call free_irq() only on enabled channels When I use OpenSUSE-11.2 on UML (> 2.6.25) I get lots of such errors: Registering fd 1 twice Irqs : 3, 3 Ids : 0x09cb41a0, 0x09cb4120 ------------[ cut here ]------------ WARNING: at kernel/irq/manage.c:896 __free_irq+0x79/0x11a() Trying to free already-free IRQ 3 Modules linked in: 09dadc6c: [<081b2edb>] dump_stack+0x1c/0x20 09dadc84: [<080716da>] warn_slowpath_common+0x49/0x77 09dadc9c: [<08071772>] warn_slowpath_fmt+0x26/0x2a 09dadcb4: [<08094e08>] __free_irq+0x79/0x11a 09dadce4: [<08094ed6>] free_irq+0x2d/0x49 09dadcf4: [<0805b4bc>] close_one_chan+0x70/0x9c 09dadd0c: [<0805b833>] close_chan+0x17/0x22 09dadd1c: [<0805bdda>] enable_chan+0x70/0x7c 09dadd3c: [<0805cbb7>] line_open+0x34/0x9f 09dadd54: [<0805b21e>] con_open+0x13/0x35 09dadd6c: [<0814dc89>] tty_open+0x285/0x384 09dadda0: [<080b754e>] chrdev_open+0xe0/0xf9 09daddc0: [<080b3fb2>] __dentry_open+0xf3/0x1e2 09dadde4: [<080b4142>] nameidata_to_filp+0x35/0x49 09daddfc: [<080bd270>] do_last+0x409/0x50e 09dade28: [<080bea04>] do_filp_open+0x175/0x446 09dadecc: [<080b3d89>] do_sys_open+0x4a/0x128 09dadf04: [<080b3ea2>] sys_open+0x19/0x21 09dadf28: [<0805ab5a>] handle_syscall+0x7a/0x98 09dadf78: [<08068441>] userspace+0x2c9/0x370 09dadfe0: [<08058bb3>] fork_handler+0x53/0x5b 09dadffc: [<00766564>] 0x766564 ---[ end trace 9ebc1094aaf4bded ]--- This patch fixes the issue. Signed-off-by: Richard Weinberger <richard@nod.at> Cc: Jeff Dike <jdike@addtoit.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-10 00:20:14 +00:00
if (chan->output && chan->enabled)
um_free_irq(chan->line->driver->write_irq, chan);
[PATCH] uml: Simplify console opening/closing and irq registration This patch simplifies the opening and closing of host console devices and the registration and deregistration of IRQs. The intent is to make it obvious that an IRQ can't exist without an open file descriptor. chan_enable will now open the channel, and when both opening and IRQ registration are desired, this should be used. Opening only is done for the initial console, so that interface still needs to exist. The free_irqs_later interface is now gone. It was intended to avoid freeing an IRQ while it was being processed. It did this, but it didn't eliminate the possiblity of free_irq being called from an interrupt, which is bad. In its place is a list of irqs to be freed, which is processed by the signal handler just before exiting. close_one_chan now disables irqs. When a host device disappears, it is just closed, and that disables IRQs. The device id registered with the IRQ is now the chan structure, not the tty. This is because the interrupt arrives on a descriptor associated with the channel. This caused equivalent changes in the arguments to line_timer_cb. line_disable is gone since it is not used any more. The count field in the line structure is gone. tty->count is used instead. The complicated logic in sigio_handler with freeing IRQs when necessary and making sure its idea of the next irq is correct is now much simpler. The irq list can't be rearranged underneath it, so it is now a simple list walk. Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:18:57 +00:00
chan->enabled = 0;
}
if (chan->ops->close != NULL)
[PATCH] uml: Simplify console opening/closing and irq registration This patch simplifies the opening and closing of host console devices and the registration and deregistration of IRQs. The intent is to make it obvious that an IRQ can't exist without an open file descriptor. chan_enable will now open the channel, and when both opening and IRQ registration are desired, this should be used. Opening only is done for the initial console, so that interface still needs to exist. The free_irqs_later interface is now gone. It was intended to avoid freeing an IRQ while it was being processed. It did this, but it didn't eliminate the possiblity of free_irq being called from an interrupt, which is bad. In its place is a list of irqs to be freed, which is processed by the signal handler just before exiting. close_one_chan now disables irqs. When a host device disappears, it is just closed, and that disables IRQs. The device id registered with the IRQ is now the chan structure, not the tty. This is because the interrupt arrives on a descriptor associated with the channel. This caused equivalent changes in the arguments to line_timer_cb. line_disable is gone since it is not used any more. The count field in the line structure is gone. tty->count is used instead. The complicated logic in sigio_handler with freeing IRQs when necessary and making sure its idea of the next irq is correct is now much simpler. The irq list can't be rearranged underneath it, so it is now a simple list walk. Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:18:57 +00:00
(*chan->ops->close)(chan->fd, chan->data);
chan->opened = 0;
chan->fd = -1;
}
void close_chan(struct line *line)
{
struct chan *chan;
/* Close in reverse order as open in case more than one of them
* refers to the same device and they save and restore that device's
* state. Then, the first one opened will have the original state,
* so it must be the last closed.
*/
list_for_each_entry_reverse(chan, &line->chan_list, list) {
close_one_chan(chan, 0);
}
}
void deactivate_chan(struct chan *chan, int irq)
{
if (chan && chan->enabled)
deactivate_fd(chan->fd, irq);
}
void reactivate_chan(struct chan *chan, int irq)
{
if (chan && chan->enabled)
reactivate_fd(chan->fd, irq);
}
int write_chan(struct chan *chan, const char *buf, int len,
int write_irq)
{
int n, ret = 0;
if (len == 0 || !chan || !chan->ops->write)
return 0;
n = chan->ops->write(chan->fd, buf, len, chan->data);
if (chan->primary) {
ret = n;
if ((ret == -EAGAIN) || ((ret >= 0) && (ret < len)))
reactivate_fd(chan->fd, write_irq);
}
return ret;
}
int console_write_chan(struct chan *chan, const char *buf, int len)
{
int n, ret = 0;
if (!chan || !chan->ops->console_write)
return 0;
n = chan->ops->console_write(chan->fd, buf, len);
if (chan->primary)
ret = n;
return ret;
}
int console_open_chan(struct line *line, struct console *co)
{
int err;
err = open_chan(&line->chan_list);
if (err)
return err;
printk(KERN_INFO "Console initialized on /dev/%s%d\n", co->name,
co->index);
return 0;
}
int chan_window_size(struct line *line, unsigned short *rows_out,
unsigned short *cols_out)
{
struct chan *chan;
chan = line->chan_in;
if (chan && chan->primary) {
if (chan->ops->window_size == NULL)
return 0;
return chan->ops->window_size(chan->fd, chan->data,
rows_out, cols_out);
}
chan = line->chan_out;
if (chan && chan->primary) {
if (chan->ops->window_size == NULL)
return 0;
return chan->ops->window_size(chan->fd, chan->data,
rows_out, cols_out);
}
return 0;
}
static void free_one_chan(struct chan *chan)
{
list_del(&chan->list);
[PATCH] uml: Simplify console opening/closing and irq registration This patch simplifies the opening and closing of host console devices and the registration and deregistration of IRQs. The intent is to make it obvious that an IRQ can't exist without an open file descriptor. chan_enable will now open the channel, and when both opening and IRQ registration are desired, this should be used. Opening only is done for the initial console, so that interface still needs to exist. The free_irqs_later interface is now gone. It was intended to avoid freeing an IRQ while it was being processed. It did this, but it didn't eliminate the possiblity of free_irq being called from an interrupt, which is bad. In its place is a list of irqs to be freed, which is processed by the signal handler just before exiting. close_one_chan now disables irqs. When a host device disappears, it is just closed, and that disables IRQs. The device id registered with the IRQ is now the chan structure, not the tty. This is because the interrupt arrives on a descriptor associated with the channel. This caused equivalent changes in the arguments to line_timer_cb. line_disable is gone since it is not used any more. The count field in the line structure is gone. tty->count is used instead. The complicated logic in sigio_handler with freeing IRQs when necessary and making sure its idea of the next irq is correct is now much simpler. The irq list can't be rearranged underneath it, so it is now a simple list walk. Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:18:57 +00:00
close_one_chan(chan, 0);
[PATCH] uml: Simplify console opening/closing and irq registration This patch simplifies the opening and closing of host console devices and the registration and deregistration of IRQs. The intent is to make it obvious that an IRQ can't exist without an open file descriptor. chan_enable will now open the channel, and when both opening and IRQ registration are desired, this should be used. Opening only is done for the initial console, so that interface still needs to exist. The free_irqs_later interface is now gone. It was intended to avoid freeing an IRQ while it was being processed. It did this, but it didn't eliminate the possiblity of free_irq being called from an interrupt, which is bad. In its place is a list of irqs to be freed, which is processed by the signal handler just before exiting. close_one_chan now disables irqs. When a host device disappears, it is just closed, and that disables IRQs. The device id registered with the IRQ is now the chan structure, not the tty. This is because the interrupt arrives on a descriptor associated with the channel. This caused equivalent changes in the arguments to line_timer_cb. line_disable is gone since it is not used any more. The count field in the line structure is gone. tty->count is used instead. The complicated logic in sigio_handler with freeing IRQs when necessary and making sure its idea of the next irq is correct is now much simpler. The irq list can't be rearranged underneath it, so it is now a simple list walk. Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:18:57 +00:00
if (chan->ops->free != NULL)
(*chan->ops->free)(chan->data);
[PATCH] uml: Simplify console opening/closing and irq registration This patch simplifies the opening and closing of host console devices and the registration and deregistration of IRQs. The intent is to make it obvious that an IRQ can't exist without an open file descriptor. chan_enable will now open the channel, and when both opening and IRQ registration are desired, this should be used. Opening only is done for the initial console, so that interface still needs to exist. The free_irqs_later interface is now gone. It was intended to avoid freeing an IRQ while it was being processed. It did this, but it didn't eliminate the possiblity of free_irq being called from an interrupt, which is bad. In its place is a list of irqs to be freed, which is processed by the signal handler just before exiting. close_one_chan now disables irqs. When a host device disappears, it is just closed, and that disables IRQs. The device id registered with the IRQ is now the chan structure, not the tty. This is because the interrupt arrives on a descriptor associated with the channel. This caused equivalent changes in the arguments to line_timer_cb. line_disable is gone since it is not used any more. The count field in the line structure is gone. tty->count is used instead. The complicated logic in sigio_handler with freeing IRQs when necessary and making sure its idea of the next irq is correct is now much simpler. The irq list can't be rearranged underneath it, so it is now a simple list walk. Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:18:57 +00:00
if (chan->primary && chan->output)
ignore_sigio_fd(chan->fd);
kfree(chan);
}
static void free_chan(struct list_head *chans)
{
struct list_head *ele, *next;
struct chan *chan;
list_for_each_safe(ele, next, chans) {
chan = list_entry(ele, struct chan, list);
free_one_chan(chan);
}
}
static int one_chan_config_string(struct chan *chan, char *str, int size,
char **error_out)
{
int n = 0;
if (chan == NULL) {
CONFIG_CHUNK(str, size, n, "none", 1);
return n;
}
CONFIG_CHUNK(str, size, n, chan->ops->type, 0);
if (chan->dev == NULL) {
CONFIG_CHUNK(str, size, n, "", 1);
return n;
}
CONFIG_CHUNK(str, size, n, ":", 0);
CONFIG_CHUNK(str, size, n, chan->dev, 0);
return n;
}
static int chan_pair_config_string(struct chan *in, struct chan *out,
char *str, int size, char **error_out)
{
int n;
n = one_chan_config_string(in, str, size, error_out);
str += n;
size -= n;
if (in == out) {
CONFIG_CHUNK(str, size, n, "", 1);
return n;
}
CONFIG_CHUNK(str, size, n, ",", 1);
n = one_chan_config_string(out, str, size, error_out);
str += n;
size -= n;
CONFIG_CHUNK(str, size, n, "", 1);
return n;
}
int chan_config_string(struct line *line, char *str, int size,
char **error_out)
{
struct chan *in = line->chan_in, *out = line->chan_out;
if (in && !in->primary)
in = NULL;
if (out && !out->primary)
out = NULL;
return chan_pair_config_string(in, out, str, size, error_out);
}
struct chan_type {
char *key;
const struct chan_ops *ops;
};
static const struct chan_type chan_table[] = {
{ "fd", &fd_ops },
#ifdef CONFIG_NULL_CHAN
{ "null", &null_ops },
#else
{ "null", &not_configged_ops },
#endif
#ifdef CONFIG_PORT_CHAN
{ "port", &port_ops },
#else
{ "port", &not_configged_ops },
#endif
#ifdef CONFIG_PTY_CHAN
{ "pty", &pty_ops },
{ "pts", &pts_ops },
#else
{ "pty", &not_configged_ops },
{ "pts", &not_configged_ops },
#endif
#ifdef CONFIG_TTY_CHAN
{ "tty", &tty_ops },
#else
{ "tty", &not_configged_ops },
#endif
#ifdef CONFIG_XTERM_CHAN
{ "xterm", &xterm_ops },
#else
{ "xterm", &not_configged_ops },
#endif
};
[PATCH] uml: Simplify console opening/closing and irq registration This patch simplifies the opening and closing of host console devices and the registration and deregistration of IRQs. The intent is to make it obvious that an IRQ can't exist without an open file descriptor. chan_enable will now open the channel, and when both opening and IRQ registration are desired, this should be used. Opening only is done for the initial console, so that interface still needs to exist. The free_irqs_later interface is now gone. It was intended to avoid freeing an IRQ while it was being processed. It did this, but it didn't eliminate the possiblity of free_irq being called from an interrupt, which is bad. In its place is a list of irqs to be freed, which is processed by the signal handler just before exiting. close_one_chan now disables irqs. When a host device disappears, it is just closed, and that disables IRQs. The device id registered with the IRQ is now the chan structure, not the tty. This is because the interrupt arrives on a descriptor associated with the channel. This caused equivalent changes in the arguments to line_timer_cb. line_disable is gone since it is not used any more. The count field in the line structure is gone. tty->count is used instead. The complicated logic in sigio_handler with freeing IRQs when necessary and making sure its idea of the next irq is correct is now much simpler. The irq list can't be rearranged underneath it, so it is now a simple list walk. Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:18:57 +00:00
static struct chan *parse_chan(struct line *line, char *str, int device,
const struct chan_opts *opts, char **error_out)
{
const struct chan_type *entry;
const struct chan_ops *ops;
struct chan *chan;
void *data;
int i;
ops = NULL;
data = NULL;
for(i = 0; i < ARRAY_SIZE(chan_table); i++) {
entry = &chan_table[i];
if (!strncmp(str, entry->key, strlen(entry->key))) {
ops = entry->ops;
str += strlen(entry->key);
break;
}
}
if (ops == NULL) {
*error_out = "No match for configured backends";
return NULL;
}
data = (*ops->init)(str, device, opts);
if (data == NULL) {
*error_out = "Configuration failed";
return NULL;
}
chan = kmalloc(sizeof(*chan), GFP_ATOMIC);
if (chan == NULL) {
*error_out = "Memory allocation failed";
return NULL;
}
*chan = ((struct chan) { .list = LIST_HEAD_INIT(chan->list),
[PATCH] uml: Simplify console opening/closing and irq registration This patch simplifies the opening and closing of host console devices and the registration and deregistration of IRQs. The intent is to make it obvious that an IRQ can't exist without an open file descriptor. chan_enable will now open the channel, and when both opening and IRQ registration are desired, this should be used. Opening only is done for the initial console, so that interface still needs to exist. The free_irqs_later interface is now gone. It was intended to avoid freeing an IRQ while it was being processed. It did this, but it didn't eliminate the possiblity of free_irq being called from an interrupt, which is bad. In its place is a list of irqs to be freed, which is processed by the signal handler just before exiting. close_one_chan now disables irqs. When a host device disappears, it is just closed, and that disables IRQs. The device id registered with the IRQ is now the chan structure, not the tty. This is because the interrupt arrives on a descriptor associated with the channel. This caused equivalent changes in the arguments to line_timer_cb. line_disable is gone since it is not used any more. The count field in the line structure is gone. tty->count is used instead. The complicated logic in sigio_handler with freeing IRQs when necessary and making sure its idea of the next irq is correct is now much simpler. The irq list can't be rearranged underneath it, so it is now a simple list walk. Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:18:57 +00:00
.free_list =
LIST_HEAD_INIT(chan->free_list),
.line = line,
.primary = 1,
.input = 0,
.output = 0,
.opened = 0,
[PATCH] uml: Simplify console opening/closing and irq registration This patch simplifies the opening and closing of host console devices and the registration and deregistration of IRQs. The intent is to make it obvious that an IRQ can't exist without an open file descriptor. chan_enable will now open the channel, and when both opening and IRQ registration are desired, this should be used. Opening only is done for the initial console, so that interface still needs to exist. The free_irqs_later interface is now gone. It was intended to avoid freeing an IRQ while it was being processed. It did this, but it didn't eliminate the possiblity of free_irq being called from an interrupt, which is bad. In its place is a list of irqs to be freed, which is processed by the signal handler just before exiting. close_one_chan now disables irqs. When a host device disappears, it is just closed, and that disables IRQs. The device id registered with the IRQ is now the chan structure, not the tty. This is because the interrupt arrives on a descriptor associated with the channel. This caused equivalent changes in the arguments to line_timer_cb. line_disable is gone since it is not used any more. The count field in the line structure is gone. tty->count is used instead. The complicated logic in sigio_handler with freeing IRQs when necessary and making sure its idea of the next irq is correct is now much simpler. The irq list can't be rearranged underneath it, so it is now a simple list walk. Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:18:57 +00:00
.enabled = 0,
.fd = -1,
.ops = ops,
.data = data });
return chan;
}
[PATCH] uml: Simplify console opening/closing and irq registration This patch simplifies the opening and closing of host console devices and the registration and deregistration of IRQs. The intent is to make it obvious that an IRQ can't exist without an open file descriptor. chan_enable will now open the channel, and when both opening and IRQ registration are desired, this should be used. Opening only is done for the initial console, so that interface still needs to exist. The free_irqs_later interface is now gone. It was intended to avoid freeing an IRQ while it was being processed. It did this, but it didn't eliminate the possiblity of free_irq being called from an interrupt, which is bad. In its place is a list of irqs to be freed, which is processed by the signal handler just before exiting. close_one_chan now disables irqs. When a host device disappears, it is just closed, and that disables IRQs. The device id registered with the IRQ is now the chan structure, not the tty. This is because the interrupt arrives on a descriptor associated with the channel. This caused equivalent changes in the arguments to line_timer_cb. line_disable is gone since it is not used any more. The count field in the line structure is gone. tty->count is used instead. The complicated logic in sigio_handler with freeing IRQs when necessary and making sure its idea of the next irq is correct is now much simpler. The irq list can't be rearranged underneath it, so it is now a simple list walk. Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:18:57 +00:00
int parse_chan_pair(char *str, struct line *line, int device,
const struct chan_opts *opts, char **error_out)
{
[PATCH] uml: Simplify console opening/closing and irq registration This patch simplifies the opening and closing of host console devices and the registration and deregistration of IRQs. The intent is to make it obvious that an IRQ can't exist without an open file descriptor. chan_enable will now open the channel, and when both opening and IRQ registration are desired, this should be used. Opening only is done for the initial console, so that interface still needs to exist. The free_irqs_later interface is now gone. It was intended to avoid freeing an IRQ while it was being processed. It did this, but it didn't eliminate the possiblity of free_irq being called from an interrupt, which is bad. In its place is a list of irqs to be freed, which is processed by the signal handler just before exiting. close_one_chan now disables irqs. When a host device disappears, it is just closed, and that disables IRQs. The device id registered with the IRQ is now the chan structure, not the tty. This is because the interrupt arrives on a descriptor associated with the channel. This caused equivalent changes in the arguments to line_timer_cb. line_disable is gone since it is not used any more. The count field in the line structure is gone. tty->count is used instead. The complicated logic in sigio_handler with freeing IRQs when necessary and making sure its idea of the next irq is correct is now much simpler. The irq list can't be rearranged underneath it, so it is now a simple list walk. Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:18:57 +00:00
struct list_head *chans = &line->chan_list;
struct chan *new;
char *in, *out;
if (!list_empty(chans)) {
line->chan_in = line->chan_out = NULL;
free_chan(chans);
INIT_LIST_HEAD(chans);
}
if (!str)
return 0;
out = strchr(str, ',');
if (out != NULL) {
in = str;
*out = '\0';
out++;
new = parse_chan(line, in, device, opts, error_out);
if (new == NULL)
return -1;
new->input = 1;
list_add(&new->list, chans);
line->chan_in = new;
new = parse_chan(line, out, device, opts, error_out);
if (new == NULL)
return -1;
list_add(&new->list, chans);
new->output = 1;
line->chan_out = new;
}
else {
new = parse_chan(line, str, device, opts, error_out);
if (new == NULL)
return -1;
list_add(&new->list, chans);
new->input = 1;
new->output = 1;
line->chan_in = line->chan_out = new;
}
return 0;
}
void chan_interrupt(struct line *line, struct tty_struct *tty, int irq)
{
struct chan *chan = line->chan_in;
int err;
char c;
if (!chan || !chan->ops->read)
goto out;
do {
if (tty && !tty_buffer_request_room(tty, 1)) {
schedule_delayed_work(&line->task, 1);
goto out;
}
err = chan->ops->read(chan->fd, &c, chan->data);
if (err > 0)
tty_receive_char(tty, c);
} while (err > 0);
if (err == 0)
reactivate_fd(chan->fd, irq);
if (err == -EIO) {
if (chan->primary) {
if (tty != NULL)
tty_hangup(tty);
if (line->chan_out != chan)
close_one_chan(line->chan_out, 1);
}
close_one_chan(chan, 1);
if (chan->primary)
return;
}
out:
if (tty)
tty_flip_buffer_push(tty);
}