#include <linux/module.h>
#include <linux/fs.h>
#include <linux/init.h>
-#include <asm/uaccess.h>
-#include <linux/slab.h>
-#include <linux/list.h>
-#include <linux/vmalloc.h>
-#include <linux/elf.h>
-#include <linux/seq_file.h>
-#include <linux/syscalls.h>
-#include <linux/moduleloader.h>
#include <linux/interrupt.h>
+#include <linux/irq.h>
#include <linux/poll.h>
#include <linux/sched.h>
#include <linux/wait.h>
+
#include <asm/mipsmtregs.h>
-#include <asm/cacheflush.h>
-#include <asm/atomic.h>
+#include <asm/bitops.h>
#include <asm/cpu.h>
#include <asm/processor.h>
-#include <asm/system.h>
-#include <asm/vpe.h>
#include <asm/rtlx.h>
+#include <asm/uaccess.h>
#define RTLX_TARG_VPE 1
static struct rtlx_info *rtlx;
static int major;
static char module_name[] = "rtlx";
+static struct irqaction irq;
+static int irq_num;
+
+static inline int spacefree(int read, int write, int size)
+{
+ if (read == write) {
+ /*
+ * never fill the buffer completely, so indexes are always
+ * equal if empty and only empty, or !equal if data available
+ */
+ return size - 1;
+ }
+
+ return ((read + size - write) % size) - 1;
+}
static struct chan_waitqueues {
wait_queue_head_t rt_queue;
wait_queue_head_t lx_queue;
- int in_open;
} channel_wqs[RTLX_CHANNELS];
-static struct irqaction irq;
-static int irq_num;
-static struct vpe_notifications notify;
-static int sp_stopping = 0;
-
extern void *vpe_get_shared(int index);
static void rtlx_dispatch(struct pt_regs *regs)
do_IRQ(MIPSCPU_INT_BASE + MIPS_CPU_RTLX_IRQ, regs);
}
-
-/* Interrupt handler may be called before rtlx_init has otherwise had
- a chance to run.
-*/
static irqreturn_t rtlx_interrupt(int irq, void *dev_id, struct pt_regs *regs)
{
int i;
- for (i = 0; i < RTLX_CHANNELS; i++) {
- wake_up(&channel_wqs[i].lx_queue);
- wake_up(&channel_wqs[i].rt_queue);
- }
-
- return IRQ_HANDLED;
-}
-
-static __attribute_used__ void dump_rtlx(void)
-{
- int i;
-
- printk("id 0x%lx state %d\n", rtlx->id, rtlx->state);
-
for (i = 0; i < RTLX_CHANNELS; i++) {
struct rtlx_channel *chan = &rtlx->channel[i];
- printk(" rt_state %d lx_state %d buffer_size %d\n",
- chan->rt_state, chan->lx_state, chan->buffer_size);
-
- printk(" rt_read %d rt_write %d\n",
- chan->rt_read, chan->rt_write);
-
- printk(" lx_read %d lx_write %d\n",
- chan->lx_read, chan->lx_write);
-
- printk(" rt_buffer <%s>\n", chan->rt_buffer);
- printk(" lx_buffer <%s>\n", chan->lx_buffer);
+ if (chan->lx_read != chan->lx_write)
+ wake_up_interruptible(&channel_wqs[i].lx_queue);
}
+
+ return IRQ_HANDLED;
}
/* call when we have the address of the shared structure from the SP side. */
static int rtlx_init(struct rtlx_info *rtlxi)
{
+ int i;
+
if (rtlxi->id != RTLX_ID) {
- printk(KERN_ERR "no valid RTLX id at 0x%p 0x%x\n", rtlxi, rtlxi->id);
+ printk(KERN_WARNING "no valid RTLX id at 0x%p\n", rtlxi);
return -ENOEXEC;
}
- rtlx = rtlxi;
-
- return 0;
-}
+ /* initialise the wait queues */
+ for (i = 0; i < RTLX_CHANNELS; i++) {
+ init_waitqueue_head(&channel_wqs[i].rt_queue);
+ init_waitqueue_head(&channel_wqs[i].lx_queue);
+ }
-/* notifications */
-static void starting(int vpe)
-{
- int i;
- sp_stopping = 0;
+ /* set up for interrupt handling */
+ memset(&irq, 0, sizeof(struct irqaction));
- /* force a reload of rtlx */
- rtlx=NULL;
+ if (cpu_has_vint)
+ set_vi_handler(MIPS_CPU_RTLX_IRQ, rtlx_dispatch);
- /* wake up any sleeping rtlx_open's */
- for (i = 0; i < RTLX_CHANNELS; i++)
- wake_up_interruptible(&channel_wqs[i].lx_queue);
-}
+ irq_num = MIPSCPU_INT_BASE + MIPS_CPU_RTLX_IRQ;
+ irq.handler = rtlx_interrupt;
+ irq.flags = SA_INTERRUPT;
+ irq.name = "RTLX";
+ irq.dev_id = rtlx;
+ setup_irq(irq_num, &irq);
-static void stopping(int vpe)
-{
- int i;
+ rtlx = rtlxi;
- sp_stopping = 1;
- for (i = 0; i < RTLX_CHANNELS; i++)
- wake_up_interruptible(&channel_wqs[i].lx_queue);
+ return 0;
}
-
-int rtlx_open(int index, int can_sleep)
+/* only allow one open process at a time to open each channel */
+static int rtlx_open(struct inode *inode, struct file *filp)
{
- int ret;
+ int minor, ret;
struct rtlx_channel *chan;
- volatile struct rtlx_info **p;
- if (index >= RTLX_CHANNELS) {
- printk(KERN_DEBUG "rtlx_open index out of range\n");
- return -ENOSYS;
- }
-
- if (channel_wqs[index].in_open) {
- printk(KERN_DEBUG "rtlx_open channel %d already opened\n", index);
- return -EBUSY;
- }
-
- channel_wqs[index].in_open++;
+ /* assume only 1 device at the mo. */
+ minor = MINOR(inode->i_rdev);
if (rtlx == NULL) {
+ struct rtlx_info **p;
if( (p = vpe_get_shared(RTLX_TARG_VPE)) == NULL) {
- if (can_sleep) {
- DECLARE_WAITQUEUE(wait, current);
-
- /* go to sleep */
- add_wait_queue(&channel_wqs[index].lx_queue, &wait);
-
- set_current_state(TASK_INTERRUPTIBLE);
- while ((p = vpe_get_shared(RTLX_TARG_VPE)) == NULL) {
- schedule();
- set_current_state(TASK_INTERRUPTIBLE);
- }
-
- set_current_state(TASK_RUNNING);
- remove_wait_queue(&channel_wqs[index].lx_queue, &wait);
-
- /* back running */
- } else {
- printk( KERN_DEBUG "No SP program loaded, and device "
- "opened with O_NONBLOCK\n");
- channel_wqs[index].in_open = 0;
- return -ENOSYS;
- }
+ printk(KERN_ERR "vpe_get_shared is NULL. "
+ "Has an SP program been loaded?\n");
+ return -EFAULT;
}
if (*p == NULL) {
- if (can_sleep) {
- DECLARE_WAITQUEUE(wait, current);
-
- /* go to sleep */
- add_wait_queue(&channel_wqs[index].lx_queue, &wait);
-
- set_current_state(TASK_INTERRUPTIBLE);
- while (*p == NULL) {
- schedule();
-
- /* reset task state to interruptable otherwise
- we'll whizz round here like a very fast loopy
- thing. schedule() appears to return with state
- set to TASK_RUNNING.
-
- If the loaded SP program, for whatever reason,
- doesn't set up the shared structure *p will never
- become true. So whoever connected to either /dev/rt?
- or if it was kspd, will then take up rather a lot of
- processor cycles.
- */
-
- set_current_state(TASK_INTERRUPTIBLE);
- }
-
- set_current_state(TASK_RUNNING);
- remove_wait_queue(&channel_wqs[index].lx_queue, &wait);
-
- /* back running */
- }
- else {
- printk(" *vpe_get_shared is NULL. "
- "Has an SP program been loaded?\n");
- channel_wqs[index].in_open = 0;
- return -ENOSYS;
- }
+ printk(KERN_ERR "vpe_shared %p %p\n", p, *p);
+ return -EFAULT;
}
- if ((unsigned int)*p < KSEG0) {
- printk(KERN_WARNING "vpe_get_shared returned an invalid pointer "
- "maybe an error code %d\n", (int)*p);
- channel_wqs[index].in_open = 0;
- return -ENOSYS;
- }
-
- if ((ret = rtlx_init(*p)) < 0) {
- channel_wqs[index].in_open = 0;
- return ret;
- }
+ if ((ret = rtlx_init(*p)) < 0)
+ return ret;
}
- chan = &rtlx->channel[index];
+ chan = &rtlx->channel[minor];
- if (chan->lx_state == RTLX_STATE_OPENED) {
- channel_wqs[index].in_open = 0;
- return -EBUSY;
- }
+ if (test_and_set_bit(RTLX_STATE_OPENED, &chan->lx_state))
+ return -EBUSY;
- chan->lx_state = RTLX_STATE_OPENED;
- channel_wqs[index].in_open = 0;
return 0;
}
-int rtlx_release(int index)
+static int rtlx_release(struct inode *inode, struct file *filp)
{
- rtlx->channel[index].lx_state = RTLX_STATE_UNUSED;
+ int minor = MINOR(inode->i_rdev);
+
+ clear_bit(RTLX_STATE_OPENED, &rtlx->channel[minor].lx_state);
+ smp_mb__after_clear_bit();
+
return 0;
}
-unsigned int rtlx_read_poll(int index, int can_sleep)
+static unsigned int rtlx_poll(struct file *file, poll_table * wait)
{
- struct rtlx_channel *chan;
+ int minor;
+ unsigned int mask = 0;
+ struct rtlx_channel *chan;
- if (rtlx == NULL)
- return 0;
+ minor = MINOR(file->f_dentry->d_inode->i_rdev);
+ chan = &rtlx->channel[minor];
- chan = &rtlx->channel[index];
+ poll_wait(file, &channel_wqs[minor].rt_queue, wait);
+ poll_wait(file, &channel_wqs[minor].lx_queue, wait);
/* data available to read? */
- if (chan->lx_read == chan->lx_write) {
- if (can_sleep) {
- DECLARE_WAITQUEUE(wait, current);
-
- /* go to sleep */
- add_wait_queue(&channel_wqs[index].lx_queue, &wait);
-
- set_current_state(TASK_INTERRUPTIBLE);
- while (chan->lx_read == chan->lx_write) {
- schedule();
-
- set_current_state(TASK_INTERRUPTIBLE);
-
- if (sp_stopping) {
- set_current_state(TASK_RUNNING);
- remove_wait_queue(&channel_wqs[index].lx_queue, &wait);
- return 0;
- }
- }
-
- set_current_state(TASK_RUNNING);
- remove_wait_queue(&channel_wqs[index].lx_queue, &wait);
+ if (chan->lx_read != chan->lx_write)
+ mask |= POLLIN | POLLRDNORM;
- /* back running */
- }
- else
- return 0;
- }
+ /* space to write */
+ if (spacefree(chan->rt_read, chan->rt_write, chan->buffer_size))
+ mask |= POLLOUT | POLLWRNORM;
- return (chan->lx_write + chan->buffer_size - chan->lx_read)
- % chan->buffer_size;
+ return mask;
}
-static inline int write_spacefree(int read, int write, int size)
+static ssize_t rtlx_read(struct file *file, char __user * buffer, size_t count,
+ loff_t * ppos)
{
- if (read == write) {
- /*
- * Never fill the buffer completely, so indexes are always
- * equal if empty and only empty, or !equal if data available
- */
- return size - 1;
- }
-
- return ((read + size - write) % size) - 1;
-}
+ unsigned long failed;
+ size_t fl = 0L;
+ int minor;
+ struct rtlx_channel *lx;
+ DECLARE_WAITQUEUE(wait, current);
-unsigned int rtlx_write_poll(int index)
-{
- struct rtlx_channel *chan = &rtlx->channel[index];
- return write_spacefree(chan->rt_read, chan->rt_write, chan->buffer_size);
-}
+ minor = MINOR(file->f_dentry->d_inode->i_rdev);
+ lx = &rtlx->channel[minor];
-static inline void copy_to(void *dst, void *src, size_t count, int user)
-{
- if (user)
- copy_to_user(dst, src, count);
- else
- memcpy(dst, src, count);
-}
+ /* data available? */
+ if (lx->lx_write == lx->lx_read) {
+ if (file->f_flags & O_NONBLOCK)
+ return 0; /* -EAGAIN makes cat whinge */
-static inline void copy_from(void *dst, void *src, size_t count, int user)
-{
- if (user)
- copy_from_user(dst, src, count);
- else
- memcpy(dst, src, count);
-}
+ /* go to sleep */
+ add_wait_queue(&channel_wqs[minor].lx_queue, &wait);
+ set_current_state(TASK_INTERRUPTIBLE);
-ssize_t rtlx_read(int index, void *buff, size_t count, int user)
-{
- size_t fl = 0L;
- struct rtlx_channel *lx;
+ while (lx->lx_write == lx->lx_read)
+ schedule();
- if (rtlx == NULL)
- return -ENOSYS;
+ set_current_state(TASK_RUNNING);
+ remove_wait_queue(&channel_wqs[minor].lx_queue, &wait);
- lx = &rtlx->channel[index];
+ /* back running */
+ }
/* find out how much in total */
count = min(count,
- (size_t)(lx->lx_write + lx->buffer_size - lx->lx_read)
- % lx->buffer_size);
+ (size_t)(lx->lx_write + lx->buffer_size - lx->lx_read) % lx->buffer_size);
/* then how much from the read pointer onwards */
- fl = min( count, (size_t)lx->buffer_size - lx->lx_read);
+ fl = min(count, (size_t)lx->buffer_size - lx->lx_read);
- copy_to(buff, &lx->lx_buffer[lx->lx_read], fl, user);
+ failed = copy_to_user (buffer, &lx->lx_buffer[lx->lx_read], fl);
+ if (failed) {
+ count = fl - failed;
+ goto out;
+ }
/* and if there is anything left at the beginning of the buffer */
- if ( count - fl )
- copy_to (buff + fl, lx->lx_buffer, count - fl, user);
+ if (count - fl) {
+ failed = copy_to_user (buffer + fl, lx->lx_buffer, count - fl);
+ if (failed) {
+ count -= failed;
+ goto out;
+ }
+ }
+out:
/* update the index */
lx->lx_read += count;
lx->lx_read %= lx->buffer_size;
return count;
}
-ssize_t rtlx_write(int index, void *buffer, size_t count, int user)
-{
- struct rtlx_channel *rt;
- size_t fl;
-
- if (rtlx == NULL)
- return(-ENOSYS);
-
- rt = &rtlx->channel[index];
-
- /* total number of bytes to copy */
- count = min(count,
- (size_t)write_spacefree(rt->rt_read, rt->rt_write,
- rt->buffer_size));
-
- /* first bit from write pointer to the end of the buffer, or count */
- fl = min(count, (size_t) rt->buffer_size - rt->rt_write);
-
- copy_from (&rt->rt_buffer[rt->rt_write], buffer, fl, user);
-
- /* if there's any left copy to the beginning of the buffer */
- if( count - fl )
- copy_from (rt->rt_buffer, buffer + fl, count - fl, user);
-
- rt->rt_write += count;
- rt->rt_write %= rt->buffer_size;
-
- return(count);
-}
-
-
-static int file_open(struct inode *inode, struct file *filp)
-{
- int minor = iminor(inode);
-
- return rtlx_open(minor, (filp->f_flags & O_NONBLOCK) ? 0 : 1);
-}
-
-static int file_release(struct inode *inode, struct file *filp)
-{
- int minor = iminor(inode);
-
- return rtlx_release(minor);
-}
-
-static unsigned int file_poll(struct file *file, poll_table * wait)
-{
- int minor;
- unsigned int mask = 0;
-
- minor = iminor(file->f_dentry->d_inode);
-
- poll_wait(file, &channel_wqs[minor].rt_queue, wait);
- poll_wait(file, &channel_wqs[minor].lx_queue, wait);
-
- if (rtlx == NULL)
- return 0;
-
- /* data available to read? */
- if (rtlx_read_poll(minor, 0))
- mask |= POLLIN | POLLRDNORM;
-
- /* space to write */
- if (rtlx_write_poll(minor))
- mask |= POLLOUT | POLLWRNORM;
-
- return mask;
-}
-
-static ssize_t file_read(struct file *file, char __user * buffer, size_t count,
- loff_t * ppos)
-{
- int minor = iminor(file->f_dentry->d_inode);
-
- /* data available? */
- if (!rtlx_read_poll(minor, (file->f_flags & O_NONBLOCK) ? 0 : 1)) {
- return 0; // -EAGAIN makes cat whinge
- }
-
- return rtlx_read(minor, buffer, count, 1);
-}
-
-static ssize_t file_write(struct file *file, const char __user * buffer,
+static ssize_t rtlx_write(struct file *file, const char __user * buffer,
size_t count, loff_t * ppos)
{
+ unsigned long failed;
int minor;
struct rtlx_channel *rt;
+ size_t fl;
DECLARE_WAITQUEUE(wait, current);
- minor = iminor(file->f_dentry->d_inode);
+ minor = MINOR(file->f_dentry->d_inode->i_rdev);
rt = &rtlx->channel[minor];
/* any space left... */
- if (!rtlx_write_poll(minor)) {
+ if (!spacefree(rt->rt_read, rt->rt_write, rt->buffer_size)) {
if (file->f_flags & O_NONBLOCK)
return -EAGAIN;
add_wait_queue(&channel_wqs[minor].rt_queue, &wait);
set_current_state(TASK_INTERRUPTIBLE);
- while (!rtlx_write_poll(minor))
+ while (!spacefree(rt->rt_read, rt->rt_write, rt->buffer_size))
schedule();
set_current_state(TASK_RUNNING);
remove_wait_queue(&channel_wqs[minor].rt_queue, &wait);
}
- return rtlx_write(minor, (void *)buffer, count, 1);
+ /* total number of bytes to copy */
+ count = min(count, (size_t)spacefree(rt->rt_read, rt->rt_write, rt->buffer_size) );
+
+ /* first bit from write pointer to the end of the buffer, or count */
+ fl = min(count, (size_t) rt->buffer_size - rt->rt_write);
+
+ failed = copy_from_user(&rt->rt_buffer[rt->rt_write], buffer, fl);
+ if (failed) {
+ count = fl - failed;
+ goto out;
+ }
+
+ /* if there's any left copy to the beginning of the buffer */
+ if (count - fl) {
+ failed = copy_from_user(rt->rt_buffer, buffer + fl, count - fl);
+ if (failed) {
+ count -= failed;
+ goto out;
+ }
+ }
+
+out:
+ rt->rt_write += count;
+ rt->rt_write %= rt->buffer_size;
+
+ return count;
}
static struct file_operations rtlx_fops = {
- .owner = THIS_MODULE,
- .open = file_open,
- .release = file_release,
- .write = file_write,
- .read = file_read,
- .poll = file_poll
-};
-
-static struct irqaction rtlx_irq = {
- .handler = rtlx_interrupt,
- .flags = IRQF_DISABLED,
- .name = "RTLX",
+ .owner = THIS_MODULE,
+ .open = rtlx_open,
+ .release = rtlx_release,
+ .write = rtlx_write,
+ .read = rtlx_read,
+ .poll = rtlx_poll
};
-static int rtlx_irq_num = MIPSCPU_INT_BASE + MIPS_CPU_RTLX_IRQ;
-
static char register_chrdev_failed[] __initdata =
KERN_ERR "rtlx_module_init: unable to register device\n";
-static int rtlx_module_init(void)
+static int __init rtlx_module_init(void)
{
- int i;
-
major = register_chrdev(0, module_name, &rtlx_fops);
if (major < 0) {
printk(register_chrdev_failed);
return major;
}
- /* initialise the wait queues */
- for (i = 0; i < RTLX_CHANNELS; i++) {
- init_waitqueue_head(&channel_wqs[i].rt_queue);
- init_waitqueue_head(&channel_wqs[i].lx_queue);
- channel_wqs[i].in_open = 0;
- }
-
- /* set up notifiers */
- notify.start = starting;
- notify.stop = stopping;
- vpe_notify(RTLX_TARG_VPE, ¬ify);
-
- if (cpu_has_vint)
- set_vi_handler(MIPS_CPU_RTLX_IRQ, rtlx_dispatch);
-
- rtlx_irq.dev_id = rtlx;
- setup_irq(rtlx_irq_num, &rtlx_irq);
-
return 0;
}
module_exit(rtlx_module_exit);
MODULE_DESCRIPTION("MIPS RTLX");
-MODULE_AUTHOR("Elizabeth Oldham, MIPS Technologies, Inc.");
+MODULE_AUTHOR("Elizabeth Clarke, MIPS Technologies, Inc.");
MODULE_LICENSE("GPL");
git://git.onelab.eu / linux-2.6.git / blobdiff