/* * dice_hwdep.c - a part of driver for DICE based devices * * Copyright (c) Clemens Ladisch * Copyright (c) 2014 Takashi Sakamoto * * Licensed under the terms of the GNU General Public License, version 2. */ #include "dice.h" static long hwdep_read(struct snd_hwdep *hwdep, char __user *buf, long count, loff_t *offset) { struct snd_dice *dice = hwdep->private_data; DEFINE_WAIT(wait); union snd_firewire_event event; spin_lock_irq(&dice->lock); while (!dice->dev_lock_changed && dice->notification_bits == 0) { prepare_to_wait(&dice->hwdep_wait, &wait, TASK_INTERRUPTIBLE); spin_unlock_irq(&dice->lock); schedule(); finish_wait(&dice->hwdep_wait, &wait); if (signal_pending(current)) return -ERESTARTSYS; spin_lock_irq(&dice->lock); } memset(&event, 0, sizeof(event)); if (dice->dev_lock_changed) { event.lock_status.type = SNDRV_FIREWIRE_EVENT_LOCK_STATUS; event.lock_status.status = dice->dev_lock_count > 0; dice->dev_lock_changed = false; count = min_t(long, count, sizeof(event.lock_status)); } else { event.dice_notification.type = SNDRV_FIREWIRE_EVENT_DICE_NOTIFICATION; event.dice_notification.notification = dice->notification_bits; dice->notification_bits = 0; count = min_t(long, count, sizeof(event.dice_notification)); } spin_unlock_irq(&dice->lock); if (copy_to_user(buf, &event, count)) return -EFAULT; return count; } static unsigned int hwdep_poll(struct snd_hwdep *hwdep, struct file *file, poll_table *wait) { struct snd_dice *dice = hwdep->private_data; unsigned int events; poll_wait(file, &dice->hwdep_wait, wait); spin_lock_irq(&dice->lock); if (dice->dev_lock_changed || dice->notification_bits != 0) events = POLLIN | POLLRDNORM; else events = 0; spin_unlock_irq(&dice->lock); return events; } static int hwdep_get_info(struct snd_dice *dice, void __user *arg) { struct fw_device *dev = fw_parent_device(dice->unit); struct snd_firewire_get_info info; memset(&info, 0, sizeof(info)); info.type = SNDRV_FIREWIRE_TYPE_DICE; info.card = dev->card->index; *(__be32 *)&info.guid[0] = cpu_to_be32(dev->config_rom[3]); *(__be32 *)&info.guid[4] = cpu_to_be32(dev->config_rom[4]); strlcpy(info.device_name, dev_name(&dev->device), sizeof(info.device_name)); if (copy_to_user(arg, &info, sizeof(info))) return -EFAULT; return 0; } static int hwdep_lock(struct snd_dice *dice) { int err; spin_lock_irq(&dice->lock); if (dice->dev_lock_count == 0) { dice->dev_lock_count = -1; err = 0; } else { err = -EBUSY; } spin_unlock_irq(&dice->lock); return err; } static int hwdep_unlock(struct snd_dice *dice) { int err; spin_lock_irq(&dice->lock); if (dice->dev_lock_count == -1) { dice->dev_lock_count = 0; err = 0; } else { err = -EBADFD; } spin_unlock_irq(&dice->lock); return err; } static int hwdep_release(struct snd_hwdep *hwdep, struct file *file) { struct snd_dice *dice = hwdep->private_data; spin_lock_irq(&dice->lock); if (dice->dev_lock_count == -1) dice->dev_lock_count = 0; spin_unlock_irq(&dice->lock); return 0; } static int hwdep_ioctl(struct snd_hwdep *hwdep, struct file *file, unsigned int cmd, unsigned long arg) { struct snd_dice *dice = hwdep->private_data; switch (cmd) { case SNDRV_FIREWIRE_IOCTL_GET_INFO: return hwdep_get_info(dice, (void __user *)arg); case SNDRV_FIREWIRE_IOCTL_LOCK: return hwdep_lock(dice); case SNDRV_FIREWIRE_IOCTL_UNLOCK: return hwdep_unlock(dice); default: return -ENOIOCTLCMD; } } #ifdef CONFIG_COMPAT static int hwdep_compat_ioctl(struct snd_hwdep *hwdep, struct file *file, unsigned int cmd, unsigned long arg) { return hwdep_ioctl(hwdep, file, cmd, (unsigned long)compat_ptr(arg)); } #else #define hwdep_compat_ioctl NULL #endif int snd_dice_create_hwdep(struct snd_dice *dice) { static const struct snd_hwdep_ops ops = { .read = hwdep_read, .release = hwdep_release, .poll = hwdep_poll, .ioctl = hwdep_ioctl, .ioctl_compat = hwdep_compat_ioctl, }; struct snd_hwdep *hwdep; int err; err = snd_hwdep_new(dice->card, "DICE", 0, &hwdep); if (err < 0) return err; strcpy(hwdep->name, "DICE"); hwdep->iface = SNDRV_HWDEP_IFACE_FW_DICE; hwdep->ops = ops; hwdep->private_data = dice; hwdep->exclusive = true; return 0; }
authorBenjamin Herrenschmidt <benh@kernel.crashing.org>2017-02-03 17:10:28 +1100
committerMichael Ellerman <mpe@ellerman.id.au>2017-02-08 23:36:29 +1100
commitd7df2443cd5f67fc6ee7c05a88e4996e8177f91b (patch)
tree098a7c0ca4fceb8a65cb1f693c9d71990388933d /include/acpi/acpixf.h
parenta0615a16f7d0ceb5804d295203c302d496d8ee91 (diff)
powerpc/mm: Fix spurrious segfaults on radix with autonuma
When autonuma (Automatic NUMA balancing) marks a PTE inaccessible it clears all the protection bits but leave the PTE valid. With the Radix MMU, an attempt at executing from such a PTE will take a fault with bit 35 of SRR1 set "SRR1_ISI_N_OR_G". It is thus incorrect to treat all such faults as errors. We should pass them to handle_mm_fault() for autonuma to deal with. The case of pages that are really not executable is handled by the existing test for VM_EXEC further down. That leaves us with catching the kernel attempts at executing user pages. We can catch that earlier, even before we do find_vma. It is never valid on powerpc for the kernel to take an exec fault to begin with. So fold that test with the existing test for the kernel faulting on kernel addresses to bail out early. Fixes: 1d18ad026844 ("powerpc/mm: Detect instruction fetch denied and report") Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Acked-by: Balbir Singh <bsingharora@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'include/acpi/acpixf.h')