X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;ds=sidebyside;f=arch%2Fmips%2Fkernel%2Frtlx.c;h=5a99e3e0c96dcdab47d209ad4b4f3297d69e560a;hb=refs%2Fheads%2Fvserver;hp=986a9cf230673010e6f9ae678798d74de0a51474;hpb=76828883507a47dae78837ab5dec5a5b4513c667;p=linux-2.6.git diff --git a/arch/mips/kernel/rtlx.c b/arch/mips/kernel/rtlx.c index 986a9cf23..5a99e3e0c 100644 --- a/arch/mips/kernel/rtlx.c +++ b/arch/mips/kernel/rtlx.c @@ -21,220 +21,343 @@ #include #include #include +#include +#include +#include +#include +#include +#include +#include +#include #include -#include #include #include #include - #include -#include +#include +#include #include #include +#include +#include #include -#include #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) +static void rtlx_dispatch(void) { - do_IRQ(MIPSCPU_INT_BASE + MIPS_CPU_RTLX_IRQ, regs); + do_IRQ(MIPSCPU_INT_BASE + MIPS_CPU_RTLX_IRQ); } -static irqreturn_t rtlx_interrupt(int irq, void *dev_id, struct pt_regs *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) { int i; for (i = 0; i < RTLX_CHANNELS; i++) { - struct rtlx_channel *chan = &rtlx->channel[i]; - - if (chan->lx_read != chan->lx_write) - wake_up_interruptible(&channel_wqs[i].lx_queue); + wake_up(&channel_wqs[i].lx_queue); + wake_up(&channel_wqs[i].rt_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) +static __attribute_used__ void dump_rtlx(void) { int i; - if (rtlxi->id != RTLX_ID) { - printk(KERN_WARNING "no valid RTLX id at 0x%p\n", rtlxi); - return -ENOEXEC; - } + printk("id 0x%lx state %d\n", rtlx->id, rtlx->state); - /* 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); - } + struct rtlx_channel *chan = &rtlx->channel[i]; - /* set up for interrupt handling */ - memset(&irq, 0, sizeof(struct irqaction)); + printk(" rt_state %d lx_state %d buffer_size %d\n", + chan->rt_state, chan->lx_state, chan->buffer_size); - if (cpu_has_vint) - set_vi_handler(MIPS_CPU_RTLX_IRQ, rtlx_dispatch); + 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); - 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); + printk(" rt_buffer <%s>\n", chan->rt_buffer); + printk(" lx_buffer <%s>\n", chan->lx_buffer); + } +} + +/* call when we have the address of the shared structure from the SP side. */ +static int rtlx_init(struct rtlx_info *rtlxi) +{ + if (rtlxi->id != RTLX_ID) { + printk(KERN_ERR "no valid RTLX id at 0x%p 0x%x\n", rtlxi, rtlxi->id); + return -ENOEXEC; + } rtlx = rtlxi; return 0; } -/* only allow one open process at a time to open each channel */ -static int rtlx_open(struct inode *inode, struct file *filp) +/* notifications */ +static void starting(int vpe) +{ + int i; + sp_stopping = 0; + + /* force a reload of rtlx */ + rtlx=NULL; + + /* wake up any sleeping rtlx_open's */ + for (i = 0; i < RTLX_CHANNELS; i++) + wake_up_interruptible(&channel_wqs[i].lx_queue); +} + +static void stopping(int vpe) { - int minor, ret; + int i; + + sp_stopping = 1; + for (i = 0; i < RTLX_CHANNELS; i++) + wake_up_interruptible(&channel_wqs[i].lx_queue); +} + + +int rtlx_open(int index, int can_sleep) +{ + int ret; struct rtlx_channel *chan; + volatile struct rtlx_info **p; - /* assume only 1 device at the mo. */ - minor = MINOR(inode->i_rdev); + 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++; if (rtlx == NULL) { - struct rtlx_info **p; if( (p = vpe_get_shared(RTLX_TARG_VPE)) == NULL) { - printk(KERN_ERR "vpe_get_shared is NULL. " - "Has an SP program been loaded?\n"); - return -EFAULT; + 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; + } } if (*p == NULL) { - printk(KERN_ERR "vpe_shared %p %p\n", p, *p); - return -EFAULT; + 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; + } } - if ((ret = rtlx_init(*p)) < 0) - return ret; + 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; + } } - chan = &rtlx->channel[minor]; + chan = &rtlx->channel[index]; - if (test_and_set_bit(RTLX_STATE_OPENED, &chan->lx_state)) - return -EBUSY; + if (chan->lx_state == RTLX_STATE_OPENED) { + channel_wqs[index].in_open = 0; + return -EBUSY; + } + chan->lx_state = RTLX_STATE_OPENED; + channel_wqs[index].in_open = 0; return 0; } -static int rtlx_release(struct inode *inode, struct file *filp) +int rtlx_release(int index) { - int minor = MINOR(inode->i_rdev); - - clear_bit(RTLX_STATE_OPENED, &rtlx->channel[minor].lx_state); - smp_mb__after_clear_bit(); - + rtlx->channel[index].lx_state = RTLX_STATE_UNUSED; return 0; } -static unsigned int rtlx_poll(struct file *file, poll_table * wait) +unsigned int rtlx_read_poll(int index, int can_sleep) { - int minor; - unsigned int mask = 0; - struct rtlx_channel *chan; + struct rtlx_channel *chan; - minor = MINOR(file->f_dentry->d_inode->i_rdev); - chan = &rtlx->channel[minor]; + if (rtlx == NULL) + return 0; - poll_wait(file, &channel_wqs[minor].rt_queue, wait); - poll_wait(file, &channel_wqs[minor].lx_queue, wait); + chan = &rtlx->channel[index]; /* data available to read? */ - if (chan->lx_read != chan->lx_write) - mask |= POLLIN | POLLRDNORM; + if (chan->lx_read == chan->lx_write) { + if (can_sleep) { + DECLARE_WAITQUEUE(wait, current); - /* space to write */ - if (spacefree(chan->rt_read, chan->rt_write, chan->buffer_size)) - mask |= POLLOUT | POLLWRNORM; + /* go to sleep */ + add_wait_queue(&channel_wqs[index].lx_queue, &wait); - return mask; + 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); + + /* back running */ + } + else + return 0; + } + + return (chan->lx_write + chan->buffer_size - chan->lx_read) + % chan->buffer_size; } -static ssize_t rtlx_read(struct file *file, char __user * buffer, size_t count, - loff_t * ppos) +static inline int write_spacefree(int read, int write, int size) { - unsigned long failed; - size_t fl = 0L; - int minor; - struct rtlx_channel *lx; - DECLARE_WAITQUEUE(wait, current); + 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; + } - minor = MINOR(file->f_dentry->d_inode->i_rdev); - lx = &rtlx->channel[minor]; + return ((read + size - write) % size) - 1; +} - /* data available? */ - if (lx->lx_write == lx->lx_read) { - if (file->f_flags & O_NONBLOCK) - return 0; /* -EAGAIN makes cat whinge */ +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); +} - /* go to sleep */ - add_wait_queue(&channel_wqs[minor].lx_queue, &wait); - set_current_state(TASK_INTERRUPTIBLE); +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); +} - while (lx->lx_write == lx->lx_read) - schedule(); +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); +} - set_current_state(TASK_RUNNING); - remove_wait_queue(&channel_wqs[minor].lx_queue, &wait); +ssize_t rtlx_read(int index, void *buff, size_t count, int user) +{ + size_t fl = 0L; + struct rtlx_channel *lx; - /* back running */ - } + if (rtlx == NULL) + return -ENOSYS; + + lx = &rtlx->channel[index]; /* 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); - failed = copy_to_user (buffer, &lx->lx_buffer[lx->lx_read], fl); - if (failed) { - count = fl - failed; - goto out; - } + copy_to(buff, &lx->lx_buffer[lx->lx_read], fl, user); /* and if there is anything left at the beginning of the buffer */ - if (count - fl) { - failed = copy_to_user (buffer + fl, lx->lx_buffer, count - fl); - if (failed) { - count -= failed; - goto out; - } - } + if ( count - fl ) + copy_to (buff + fl, lx->lx_buffer, count - fl, user); -out: /* update the index */ lx->lx_read += count; lx->lx_read %= lx->buffer_size; @@ -242,20 +365,100 @@ out: return count; } -static ssize_t rtlx_write(struct file *file, const char __user * buffer, +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_path.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_path.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, size_t count, loff_t * ppos) { - unsigned long failed; int minor; struct rtlx_channel *rt; - size_t fl; DECLARE_WAITQUEUE(wait, current); - minor = MINOR(file->f_dentry->d_inode->i_rdev); + minor = iminor(file->f_path.dentry->d_inode); rt = &rtlx->channel[minor]; /* any space left... */ - if (!spacefree(rt->rt_read, rt->rt_write, rt->buffer_size)) { + if (!rtlx_write_poll(minor)) { if (file->f_flags & O_NONBLOCK) return -EAGAIN; @@ -263,61 +466,64 @@ static ssize_t rtlx_write(struct file *file, const char __user * buffer, add_wait_queue(&channel_wqs[minor].rt_queue, &wait); set_current_state(TASK_INTERRUPTIBLE); - while (!spacefree(rt->rt_read, rt->rt_write, rt->buffer_size)) + while (!rtlx_write_poll(minor)) schedule(); set_current_state(TASK_RUNNING); remove_wait_queue(&channel_wqs[minor].rt_queue, &wait); } - /* 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; + return rtlx_write(minor, (void *)buffer, count, 1); } static struct file_operations rtlx_fops = { - .owner = THIS_MODULE, - .open = rtlx_open, - .release = rtlx_release, - .write = rtlx_write, - .read = rtlx_read, - .poll = rtlx_poll + .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", }; +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 __init rtlx_module_init(void) +static int 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; } @@ -330,5 +536,5 @@ module_init(rtlx_module_init); module_exit(rtlx_module_exit); MODULE_DESCRIPTION("MIPS RTLX"); -MODULE_AUTHOR("Elizabeth Clarke, MIPS Technologies, Inc."); +MODULE_AUTHOR("Elizabeth Oldham, MIPS Technologies, Inc."); MODULE_LICENSE("GPL");