?? ide3.c
字號:
* all away */void ide_dma_timeout_retry(ide_drive_t *drive){ ide_hwif_t *hwif = HWIF(drive); struct request *rq; /* * end current dma transaction */ (void) hwif->dmaproc(ide_dma_end, drive); /* * complain a little, later we might remove some of this verbosity */ printk("%s: timeout waiting for DMA\n", drive->name); (void) hwif->dmaproc(ide_dma_timeout, drive); /* * disable dma for now, but remember that we did so because of * a timeout -- we'll reenable after we finish this next request * (or rather the first chunk of it) in pio. */ drive->retry_pio++; drive->state = DMA_PIO_RETRY; (void) hwif->dmaproc(ide_dma_off_quietly, drive); /* * un-busy drive etc (hwgroup->busy is cleared on return) and * make sure request is sane */ rq = HWGROUP(drive)->rq; HWGROUP(drive)->rq = NULL; rq->errors = 0; rq->sector = rq->bh->b_rsector; rq->current_nr_sectors = rq->bh->b_size >> 9; rq->buffer = rq->bh->b_data;}/* * ide_timer_expiry() is our timeout function for all drive operations. * But note that it can also be invoked as a result of a "sleep" operation * triggered by the mod_timer() call in ide_do_request. */void ide_timer_expiry (unsigned long data){ ide_hwgroup_t *hwgroup = (ide_hwgroup_t *) data; ide_handler_t *handler; ide_expiry_t *expiry; unsigned long flags; unsigned long wait; spin_lock_irqsave(&io_request_lock, flags); del_timer(&hwgroup->timer); if ((handler = hwgroup->handler) == NULL) { /* * Either a marginal timeout occurred * (got the interrupt just as timer expired), * or we were "sleeping" to give other devices a chance. * Either way, we don't really want to complain about anything. */ if (hwgroup->sleeping) { hwgroup->sleeping = 0; hwgroup->busy = 0; } } else { ide_drive_t *drive = hwgroup->drive; if (!drive) { printk("ide_timer_expiry: hwgroup->drive was NULL\n"); hwgroup->handler = NULL; } else { ide_hwif_t *hwif; ide_startstop_t startstop; if (!hwgroup->busy) { hwgroup->busy = 1; /* paranoia */ printk("%s: ide_timer_expiry: hwgroup->busy was 0 ??\n", drive->name); } if ((expiry = hwgroup->expiry) != NULL) { /* continue */ if ((wait = expiry(drive)) != 0) { /* reset timer */ hwgroup->timer.expires = jiffies + wait; add_timer(&hwgroup->timer); spin_unlock_irqrestore(&io_request_lock, flags); return; } } hwgroup->handler = NULL; /* * We need to simulate a real interrupt when invoking * the handler() function, which means we need to globally * mask the specific IRQ: */ spin_unlock(&io_request_lock); hwif = HWIF(drive);#if DISABLE_IRQ_NOSYNC disable_irq_nosync(hwif->hw.irq);#else disable_irq(hwif->hw.irq); /* disable_irq_nosync ?? */#endif /* DISABLE_IRQ_NOSYNC */ __cli(); /* local CPU only, as if we were handling an interrupt */ if (hwgroup->poll_timeout != 0) { startstop = handler(drive); } else if (drive_is_ready(drive)) { if (drive->waiting_for_dma) (void) hwgroup->hwif->dmaproc(ide_dma_lostirq, drive); (void)ide_ack_intr(hwif); printk("%s: lost interrupt\n", drive->name); startstop = handler(drive); } else { if (drive->waiting_for_dma) { startstop = ide_stopped; ide_dma_timeout_retry(drive); } else startstop = ide_error(drive, "irq timeout", GET_STAT()); } set_recovery_timer(hwif); drive->service_time = jiffies - drive->service_start; enable_irq(hwif->hw.irq); spin_lock_irq(&io_request_lock); if (startstop == ide_stopped) hwgroup->busy = 0; } } ide_do_request(hwgroup, 0); spin_unlock_irqrestore(&io_request_lock, flags);}/* * There's nothing really useful we can do with an unexpected interrupt, * other than reading the status register (to clear it), and logging it. * There should be no way that an irq can happen before we're ready for it, * so we needn't worry much about losing an "important" interrupt here. * * On laptops (and "green" PCs), an unexpected interrupt occurs whenever the * drive enters "idle", "standby", or "sleep" mode, so if the status looks * "good", we just ignore the interrupt completely. * * This routine assumes __cli() is in effect when called. * * If an unexpected interrupt happens on irq15 while we are handling irq14 * and if the two interfaces are "serialized" (CMD640), then it looks like * we could screw up by interfering with a new request being set up for irq15. * * In reality, this is a non-issue. The new command is not sent unless the * drive is ready to accept one, in which case we know the drive is not * trying to interrupt us. And ide_set_handler() is always invoked before * completing the issuance of any new drive command, so we will not be * accidentally invoked as a result of any valid command completion interrupt. * */static void unexpected_intr (int irq, ide_hwgroup_t *hwgroup){ byte stat; ide_hwif_t *hwif = hwgroup->hwif; /* * handle the unexpected interrupt */ do { if (hwif->hw.irq == irq) { stat = IN_BYTE(hwif->hw.io_ports[IDE_STATUS_OFFSET]); if (!OK_STAT(stat, READY_STAT, BAD_STAT)) { /* Try to not flood the console with msgs */ static unsigned long last_msgtime, count; ++count; if (0 < (signed long)(jiffies - (last_msgtime + HZ))) { last_msgtime = jiffies; printk("%s%s: unexpected interrupt, status=0x%02x, count=%ld\n", hwif->name, (hwif->next == hwgroup->hwif) ? "" : "(?)", stat, count); } } } } while ((hwif = hwif->next) != hwgroup->hwif);}/* * entry point for all interrupts, caller does __cli() for us */void ide_intr (int irq, void *dev_id, struct pt_regs *regs){ unsigned long flags; ide_hwgroup_t *hwgroup = (ide_hwgroup_t *)dev_id; ide_hwif_t *hwif; ide_drive_t *drive; ide_handler_t *handler; ide_startstop_t startstop; spin_lock_irqsave(&io_request_lock, flags); hwif = hwgroup->hwif; if (!ide_ack_intr(hwif)) { spin_unlock_irqrestore(&io_request_lock, flags); return; } if ((handler = hwgroup->handler) == NULL || hwgroup->poll_timeout != 0) { /* * Not expecting an interrupt from this drive. * That means this could be: * (1) an interrupt from another PCI device * sharing the same PCI INT# as us. * or (2) a drive just entered sleep or standby mode, * and is interrupting to let us know. * or (3) a spurious interrupt of unknown origin. * * For PCI, we cannot tell the difference, * so in that case we just ignore it and hope it goes away. */#ifdef CONFIG_BLK_DEV_IDEPCI if (IDE_PCI_DEVID_EQ(hwif->pci_devid, IDE_PCI_DEVID_NULL))#endif /* CONFIG_BLK_DEV_IDEPCI */ { /* * Probably not a shared PCI interrupt, * so we can safely try to do something about it: */ unexpected_intr(irq, hwgroup);#ifdef CONFIG_BLK_DEV_IDEPCI } else { /* * Whack the status register, just in case we have a leftover pending IRQ. */ (void) IN_BYTE(hwif->hw.io_ports[IDE_STATUS_OFFSET]);#endif /* CONFIG_BLK_DEV_IDEPCI */ } spin_unlock_irqrestore(&io_request_lock, flags); return; } drive = hwgroup->drive; if (!drive) { /* * This should NEVER happen, and there isn't much we could do about it here. */ spin_unlock_irqrestore(&io_request_lock, flags); return; } if (!drive_is_ready(drive)) { /* * This happens regularly when we share a PCI IRQ with another device. * Unfortunately, it can also happen with some buggy drives that trigger * the IRQ before their status register is up to date. Hopefully we have * enough advance overhead that the latter isn't a problem. */ spin_unlock_irqrestore(&io_request_lock, flags); return; } if (!hwgroup->busy) { hwgroup->busy = 1; /* paranoia */ printk("%s: ide_intr: hwgroup->busy was 0 ??\n", drive->name); } hwgroup->handler = NULL; del_timer(&hwgroup->timer); spin_unlock(&io_request_lock); if (drive->unmask) ide__sti(); /* local CPU only */ startstop = handler(drive); /* service this interrupt, may set handler for next interrupt */ spin_lock_irq(&io_request_lock); /* * Note that handler() may have set things up for another * interrupt to occur soon, but it cannot happen until * we exit from this routine, because it will be the * same irq as is currently being serviced here, and Linux * won't allow another of the same (on any CPU) until we return. */ set_recovery_timer(HWIF(drive)); drive->service_time = jiffies - drive->service_start; if (startstop == ide_stopped) { if (hwgroup->handler == NULL) { /* paranoia */ hwgroup->busy = 0; ide_do_request(hwgroup, hwif->hw.irq); } else { printk("%s: ide_intr: huh? expected NULL handler on exit\n", drive->name); } } spin_unlock_irqrestore(&io_request_lock, flags);}/* * get_info_ptr() returns the (ide_drive_t *) for a given device number. * It returns NULL if the given device number does not match any present drives. */ide_drive_t *get_info_ptr (kdev_t i_rdev){ int major = MAJOR(i_rdev);#if 0 int minor = MINOR(i_rdev) & PARTN_MASK;#endif unsigned int h; for (h = 0; h < MAX_HWIFS; ++h) { ide_hwif_t *hwif = &ide_hwifs[h]; if (hwif->present && major == hwif->major) { unsigned unit = DEVICE_NR(i_rdev); if (unit < MAX_DRIVES) { ide_drive_t *drive = &hwif->drives[unit];#if 0 if ((drive->present) && (drive->part[minor].nr_sects))#else if (drive->present)#endif return drive; } break; } } return NULL;}/* * This function is intended to be used prior to invoking ide_do_drive_cmd(). */void ide_init_drive_cmd (struct request *rq){ memset(rq, 0, sizeof(*rq)); rq->cmd = IDE_DRIVE_CMD;}/* * This function issues a special IDE device request * onto the request queue. * * If action is ide_wait, then the rq is queued at the end of the * request queue, and the function sleeps until it has been processed. * This is for use when invoked from an ioctl handler. * * If action is ide_preempt, then the rq is queued at the head of * the request queue, displacing the currently-being-processed * request and this function returns immediately without waiting * for the new rq to be completed. This is VERY DANGEROUS, and is * intended for careful use by the ATAPI tape/cdrom driver code. * * If action is ide_next, then the rq is queued immediately after * the currently-being-processed-request (if any), and the function * returns without waiting for the new rq to be completed. As above, * This is VERY DANGEROUS, and is intended for careful use by the * ATAPI tape/cdrom driver code. * * If action is ide_end, then the rq is queued at the end of the * request queue, and the function returns immediately without waiting * for the new rq to be completed. This is again intended for careful * use by the ATAPI tape/cdrom driver code. */int ide_do_drive_cmd (ide_drive_t *drive, struct request *rq, ide_action_t action){ unsigned long flags; ide_hwgroup_t *hwgroup = HWGROUP(drive); unsigned int major = HWIF(drive)->major; struct list_head *queue_head = &drive->queue.queue_head; DECLARE_COMPLETION(wait);#ifdef CONFIG_BLK_DEV_PDC4030 if (HWIF(drive)->chipset == ide_pdc4030 && rq->buffer != NULL) return -ENOSYS; /* special drive cmds not supported */#endif rq->errors = 0; rq->rq_status = RQ_ACTIVE; rq->rq_dev = MKDEV(major,(drive->select.b.unit)<<PARTN_BITS); if (action == ide_wait) rq->waiting = &wait; spin_lock_irqsave(&io_request_lock, flags); if (list_empty(queue_head) || action == ide_preempt) { if (action == ide_preempt) hwgroup->rq = NULL; } else { if (action == ide_wait || action == ide_end) { queue_head = queue_head->prev; } else queue_head = queue_head->next; } list_add(&rq->queue, queue_head); ide_do_request(hwgroup, 0); spin_unlock_irqrestore(&io_request_lock, flags); if (action == ide_wait) { wait_for_completion(&wait); /* wait for it to be serviced */ return rq->errors ? -EIO : 0; /* return -EIO if errors */ } return 0;}/* * This routine is called to flush all partitions and partition tables * for a changed disk, and then re-read the new partition table. * If we are revalidating a disk because of a media change, then we * enter with usage == 0. If we are using an ioctl, we automatically have * usage == 1 (we need an open channel to use an ioctl :-), so this * is our limit. */int ide_revalidate_disk (kdev_t i_rdev){ ide_drive_t *drive; ide_hwgroup_t *hwgroup; unsigned int p, major, minor; unsigned long flags; if ((drive = get_info_ptr(i_rdev)) == NULL) return -ENODEV; major = MAJOR(i_rdev); minor = drive->select.b.unit << PARTN_BITS; hwgroup = HWGROUP(drive); spin_lock_irqsave(&io_request_lock, flags); if (drive->busy || (drive->usage > 1)) { spin_unlock_irqre
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