| Author | Tokens | Token Proportion | Commits | Commit Proportion |
|---|---|---|---|---|
| H Hartley Sweeten | 6731 | 54.00% | 49 | 22.27% |
| Ian Abbott | 3865 | 31.01% | 118 | 53.64% |
| David A. Schleef | 1254 | 10.06% | 1 | 0.45% |
| Spencer E. Olson | 203 | 1.63% | 2 | 0.91% |
| Frank Mori Hess | 108 | 0.87% | 2 | 0.91% |
| Greg Kroah-Hartman | 105 | 0.84% | 9 | 4.09% |
| Bernd Porr | 42 | 0.34% | 2 | 0.91% |
| Bill Pemberton | 38 | 0.30% | 10 | 4.55% |
| Leslie Klein | 25 | 0.20% | 1 | 0.45% |
| Shyam Saini | 14 | 0.11% | 1 | 0.45% |
| Arnd Bergmann | 11 | 0.09% | 2 | 0.91% |
| Haneen Mohammed | 8 | 0.06% | 1 | 0.45% |
| Federico Vaga | 8 | 0.06% | 2 | 0.91% |
| Wolfgang Ocker | 6 | 0.05% | 1 | 0.45% |
| Al Viro | 5 | 0.04% | 2 | 0.91% |
| Anton Protopopov | 5 | 0.04% | 1 | 0.45% |
| Linus Torvalds | 4 | 0.03% | 1 | 0.45% |
| sayli karnik | 4 | 0.03% | 1 | 0.45% |
| Chase Southwood | 4 | 0.03% | 1 | 0.45% |
| Teodora Baluta | 4 | 0.03% | 1 | 0.45% |
| Bryan Garza | 3 | 0.02% | 1 | 0.45% |
| Sandhya Bankar | 3 | 0.02% | 1 | 0.45% |
| Matias Mucciolo | 3 | 0.02% | 1 | 0.45% |
| Cheah Kok Cheong | 3 | 0.02% | 1 | 0.45% |
| Giulio Benetti | 2 | 0.02% | 1 | 0.45% |
| Florian Schmaus | 2 | 0.02% | 2 | 0.91% |
| Ingo Molnar | 1 | 0.01% | 1 | 0.45% |
| Carlos E. Garcia | 1 | 0.01% | 1 | 0.45% |
| Heena Sirwani | 1 | 0.01% | 1 | 0.45% |
| Santhosh Pai | 1 | 0.01% | 1 | 0.45% |
| Kirill A. Shutemov | 1 | 0.01% | 1 | 0.45% |
| Total | 12465 | 220 |
// SPDX-License-Identifier: GPL-2.0+ /* * comedi/comedi_fops.c * comedi kernel module * * COMEDI - Linux Control and Measurement Device Interface * Copyright (C) 1997-2000 David A. Schleef <ds@schleef.org> */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include "comedi_compat32.h" #include <linux/module.h> #include <linux/errno.h> #include <linux/kernel.h> #include <linux/sched/signal.h> #include <linux/fcntl.h> #include <linux/delay.h> #include <linux/mm.h> #include <linux/slab.h> #include <linux/poll.h> #include <linux/device.h> #include <linux/fs.h> #include "comedidev.h" #include <linux/cdev.h> #include <linux/io.h> #include <linux/uaccess.h> #include "comedi_internal.h" /* * comedi_subdevice "runflags" * COMEDI_SRF_RT: DEPRECATED: command is running real-time * COMEDI_SRF_ERROR: indicates an COMEDI_CB_ERROR event has occurred * since the last command was started * COMEDI_SRF_RUNNING: command is running * COMEDI_SRF_FREE_SPRIV: free s->private on detach * * COMEDI_SRF_BUSY_MASK: runflags that indicate the subdevice is "busy" */ #define COMEDI_SRF_RT BIT(1) #define COMEDI_SRF_ERROR BIT(2) #define COMEDI_SRF_RUNNING BIT(27) #define COMEDI_SRF_FREE_SPRIV BIT(31) #define COMEDI_SRF_BUSY_MASK (COMEDI_SRF_ERROR | COMEDI_SRF_RUNNING) /** * struct comedi_file - Per-file private data for COMEDI device * @dev: COMEDI device. * @read_subdev: Current "read" subdevice. * @write_subdev: Current "write" subdevice. * @last_detach_count: Last known detach count. * @last_attached: Last known attached/detached state. */ struct comedi_file { struct comedi_device *dev; struct comedi_subdevice *read_subdev; struct comedi_subdevice *write_subdev; unsigned int last_detach_count; unsigned int last_attached:1; }; #define COMEDI_NUM_MINORS 0x100 #define COMEDI_NUM_SUBDEVICE_MINORS \ (COMEDI_NUM_MINORS - COMEDI_NUM_BOARD_MINORS) static unsigned short comedi_num_legacy_minors; module_param(comedi_num_legacy_minors, ushort, 0444); MODULE_PARM_DESC(comedi_num_legacy_minors, "number of comedi minor devices to reserve for non-auto-configured devices (default 0)" ); unsigned int comedi_default_buf_size_kb = CONFIG_COMEDI_DEFAULT_BUF_SIZE_KB; module_param(comedi_default_buf_size_kb, uint, 0644); MODULE_PARM_DESC(comedi_default_buf_size_kb, "default asynchronous buffer size in KiB (default " __MODULE_STRING(CONFIG_COMEDI_DEFAULT_BUF_SIZE_KB) ")"); unsigned int comedi_default_buf_maxsize_kb = CONFIG_COMEDI_DEFAULT_BUF_MAXSIZE_KB; module_param(comedi_default_buf_maxsize_kb, uint, 0644); MODULE_PARM_DESC(comedi_default_buf_maxsize_kb, "default maximum size of asynchronous buffer in KiB (default " __MODULE_STRING(CONFIG_COMEDI_DEFAULT_BUF_MAXSIZE_KB) ")"); static DEFINE_MUTEX(comedi_board_minor_table_lock); static struct comedi_device *comedi_board_minor_table[COMEDI_NUM_BOARD_MINORS]; static DEFINE_MUTEX(comedi_subdevice_minor_table_lock); /* Note: indexed by minor - COMEDI_NUM_BOARD_MINORS. */ static struct comedi_subdevice *comedi_subdevice_minor_table[COMEDI_NUM_SUBDEVICE_MINORS]; static struct class *comedi_class; static struct cdev comedi_cdev; static void comedi_device_init(struct comedi_device *dev) { kref_init(&dev->refcount); spin_lock_init(&dev->spinlock); mutex_init(&dev->mutex); init_rwsem(&dev->attach_lock); dev->minor = -1; } static void comedi_dev_kref_release(struct kref *kref) { struct comedi_device *dev = container_of(kref, struct comedi_device, refcount); mutex_destroy(&dev->mutex); put_device(dev->class_dev); kfree(dev); } /** * comedi_dev_put() - Release a use of a COMEDI device * @dev: COMEDI device. * * Must be called when a user of a COMEDI device is finished with it. * When the last user of the COMEDI device calls this function, the * COMEDI device is destroyed. * * Return: 1 if the COMEDI device is destroyed by this call or @dev is * NULL, otherwise return 0. Callers must not assume the COMEDI * device is still valid if this function returns 0. */ int comedi_dev_put(struct comedi_device *dev) { if (dev) return kref_put(&dev->refcount, comedi_dev_kref_release); return 1; } EXPORT_SYMBOL_GPL(comedi_dev_put); static struct comedi_device *comedi_dev_get(struct comedi_device *dev) { if (dev) kref_get(&dev->refcount); return dev; } static void comedi_device_cleanup(struct comedi_device *dev) { struct module *driver_module = NULL; if (!dev) return; mutex_lock(&dev->mutex); if (dev->attached) driver_module = dev->driver->module; comedi_device_detach(dev); if (driver_module && dev->use_count) module_put(driver_module); mutex_unlock(&dev->mutex); } static bool comedi_clear_board_dev(struct comedi_device *dev) { unsigned int i = dev->minor; bool cleared = false; mutex_lock(&comedi_board_minor_table_lock); if (dev == comedi_board_minor_table[i]) { comedi_board_minor_table[i] = NULL; cleared = true; } mutex_unlock(&comedi_board_minor_table_lock); return cleared; } static struct comedi_device *comedi_clear_board_minor(unsigned int minor) { struct comedi_device *dev; mutex_lock(&comedi_board_minor_table_lock); dev = comedi_board_minor_table[minor]; comedi_board_minor_table[minor] = NULL; mutex_unlock(&comedi_board_minor_table_lock); return dev; } static void comedi_free_board_dev(struct comedi_device *dev) { if (dev) { comedi_device_cleanup(dev); if (dev->class_dev) { device_destroy(comedi_class, MKDEV(COMEDI_MAJOR, dev->minor)); } comedi_dev_put(dev); } } static struct comedi_subdevice * comedi_subdevice_from_minor(const struct comedi_device *dev, unsigned int minor) { struct comedi_subdevice *s; unsigned int i = minor - COMEDI_NUM_BOARD_MINORS; mutex_lock(&comedi_subdevice_minor_table_lock); s = comedi_subdevice_minor_table[i]; if (s && s->device != dev) s = NULL; mutex_unlock(&comedi_subdevice_minor_table_lock); return s; } static struct comedi_device *comedi_dev_get_from_board_minor(unsigned int minor) { struct comedi_device *dev; mutex_lock(&comedi_board_minor_table_lock); dev = comedi_dev_get(comedi_board_minor_table[minor]); mutex_unlock(&comedi_board_minor_table_lock); return dev; } static struct comedi_device * comedi_dev_get_from_subdevice_minor(unsigned int minor) { struct comedi_device *dev; struct comedi_subdevice *s; unsigned int i = minor - COMEDI_NUM_BOARD_MINORS; mutex_lock(&comedi_subdevice_minor_table_lock); s = comedi_subdevice_minor_table[i]; dev = comedi_dev_get(s ? s->device : NULL); mutex_unlock(&comedi_subdevice_minor_table_lock); return dev; } /** * comedi_dev_get_from_minor() - Get COMEDI device by minor device number * @minor: Minor device number. * * Finds the COMEDI device associated with the minor device number, if any, * and increments its reference count. The COMEDI device is prevented from * being freed until a matching call is made to comedi_dev_put(). * * Return: A pointer to the COMEDI device if it exists, with its usage * reference incremented. Return NULL if no COMEDI device exists with the * specified minor device number. */ struct comedi_device *comedi_dev_get_from_minor(unsigned int minor) { if (minor < COMEDI_NUM_BOARD_MINORS) return comedi_dev_get_from_board_minor(minor); return comedi_dev_get_from_subdevice_minor(minor); } EXPORT_SYMBOL_GPL(comedi_dev_get_from_minor); static struct comedi_subdevice * comedi_read_subdevice(const struct comedi_device *dev, unsigned int minor) { struct comedi_subdevice *s; if (minor >= COMEDI_NUM_BOARD_MINORS) { s = comedi_subdevice_from_minor(dev, minor); if (!s || (s->subdev_flags & SDF_CMD_READ)) return s; } return dev->read_subdev; } static struct comedi_subdevice * comedi_write_subdevice(const struct comedi_device *dev, unsigned int minor) { struct comedi_subdevice *s; if (minor >= COMEDI_NUM_BOARD_MINORS) { s = comedi_subdevice_from_minor(dev, minor); if (!s || (s->subdev_flags & SDF_CMD_WRITE)) return s; } return dev->write_subdev; } static void comedi_file_reset(struct file *file) { struct comedi_file *cfp = file->private_data; struct comedi_device *dev = cfp->dev; struct comedi_subdevice *s, *read_s, *write_s; unsigned int minor = iminor(file_inode(file)); read_s = dev->read_subdev; write_s = dev->write_subdev; if (minor >= COMEDI_NUM_BOARD_MINORS) { s = comedi_subdevice_from_minor(dev, minor); if (!s || s->subdev_flags & SDF_CMD_READ) read_s = s; if (!s || s->subdev_flags & SDF_CMD_WRITE) write_s = s; } cfp->last_attached = dev->attached; cfp->last_detach_count = dev->detach_count; WRITE_ONCE(cfp->read_subdev, read_s); WRITE_ONCE(cfp->write_subdev, write_s); } static void comedi_file_check(struct file *file) { struct comedi_file *cfp = file->private_data; struct comedi_device *dev = cfp->dev; if (cfp->last_attached != dev->attached || cfp->last_detach_count != dev->detach_count) comedi_file_reset(file); } static struct comedi_subdevice *comedi_file_read_subdevice(struct file *file) { struct comedi_file *cfp = file->private_data; comedi_file_check(file); return READ_ONCE(cfp->read_subdev); } static struct comedi_subdevice *comedi_file_write_subdevice(struct file *file) { struct comedi_file *cfp = file->private_data; comedi_file_check(file); return READ_ONCE(cfp->write_subdev); } static int resize_async_buffer(struct comedi_device *dev, struct comedi_subdevice *s, unsigned int new_size) { struct comedi_async *async = s->async; int retval; if (new_size > async->max_bufsize) return -EPERM; if (s->busy) { dev_dbg(dev->class_dev, "subdevice is busy, cannot resize buffer\n"); return -EBUSY; } if (comedi_buf_is_mmapped(s)) { dev_dbg(dev->class_dev, "subdevice is mmapped, cannot resize buffer\n"); return -EBUSY; } /* make sure buffer is an integral number of pages (we round up) */ new_size = (new_size + PAGE_SIZE - 1) & PAGE_MASK; retval = comedi_buf_alloc(dev, s, new_size); if (retval < 0) return retval; if (s->buf_change) { retval = s->buf_change(dev, s); if (retval < 0) return retval; } dev_dbg(dev->class_dev, "subd %d buffer resized to %i bytes\n", s->index, async->prealloc_bufsz); return 0; } /* sysfs attribute files */ static ssize_t max_read_buffer_kb_show(struct device *csdev, struct device_attribute *attr, char *buf) { unsigned int minor = MINOR(csdev->devt); struct comedi_device *dev; struct comedi_subdevice *s; unsigned int size = 0; dev = comedi_dev_get_from_minor(minor); if (!dev) return -ENODEV; mutex_lock(&dev->mutex); s = comedi_read_subdevice(dev, minor); if (s && (s->subdev_flags & SDF_CMD_READ) && s->async) size = s->async->max_bufsize / 1024; mutex_unlock(&dev->mutex); comedi_dev_put(dev); return snprintf(buf, PAGE_SIZE, "%u\n", size); } static ssize_t max_read_buffer_kb_store(struct device *csdev, struct device_attribute *attr, const char *buf, size_t count) { unsigned int minor = MINOR(csdev->devt); struct comedi_device *dev; struct comedi_subdevice *s; unsigned int size; int err; err = kstrtouint(buf, 10, &size); if (err) return err; if (size > (UINT_MAX / 1024)) return -EINVAL; size *= 1024; dev = comedi_dev_get_from_minor(minor); if (!dev) return -ENODEV; mutex_lock(&dev->mutex); s = comedi_read_subdevice(dev, minor); if (s && (s->subdev_flags & SDF_CMD_READ) && s->async) s->async->max_bufsize = size; else err = -EINVAL; mutex_unlock(&dev->mutex); comedi_dev_put(dev); return err ? err : count; } static DEVICE_ATTR_RW(max_read_buffer_kb); static ssize_t read_buffer_kb_show(struct device *csdev, struct device_attribute *attr, char *buf) { unsigned int minor = MINOR(csdev->devt); struct comedi_device *dev; struct comedi_subdevice *s; unsigned int size = 0; dev = comedi_dev_get_from_minor(minor); if (!dev) return -ENODEV; mutex_lock(&dev->mutex); s = comedi_read_subdevice(dev, minor); if (s && (s->subdev_flags & SDF_CMD_READ) && s->async) size = s->async->prealloc_bufsz / 1024; mutex_unlock(&dev->mutex); comedi_dev_put(dev); return snprintf(buf, PAGE_SIZE, "%u\n", size); } static ssize_t read_buffer_kb_store(struct device *csdev, struct device_attribute *attr, const char *buf, size_t count) { unsigned int minor = MINOR(csdev->devt); struct comedi_device *dev; struct comedi_subdevice *s; unsigned int size; int err; err = kstrtouint(buf, 10, &size); if (err) return err; if (size > (UINT_MAX / 1024)) return -EINVAL; size *= 1024; dev = comedi_dev_get_from_minor(minor); if (!dev) return -ENODEV; mutex_lock(&dev->mutex); s = comedi_read_subdevice(dev, minor); if (s && (s->subdev_flags & SDF_CMD_READ) && s->async) err = resize_async_buffer(dev, s, size); else err = -EINVAL; mutex_unlock(&dev->mutex); comedi_dev_put(dev); return err ? err : count; } static DEVICE_ATTR_RW(read_buffer_kb); static ssize_t max_write_buffer_kb_show(struct device *csdev, struct device_attribute *attr, char *buf) { unsigned int minor = MINOR(csdev->devt); struct comedi_device *dev; struct comedi_subdevice *s; unsigned int size = 0; dev = comedi_dev_get_from_minor(minor); if (!dev) return -ENODEV; mutex_lock(&dev->mutex); s = comedi_write_subdevice(dev, minor); if (s && (s->subdev_flags & SDF_CMD_WRITE) && s->async) size = s->async->max_bufsize / 1024; mutex_unlock(&dev->mutex); comedi_dev_put(dev); return snprintf(buf, PAGE_SIZE, "%u\n", size); } static ssize_t max_write_buffer_kb_store(struct device *csdev, struct device_attribute *attr, const char *buf, size_t count) { unsigned int minor = MINOR(csdev->devt); struct comedi_device *dev; struct comedi_subdevice *s; unsigned int size; int err; err = kstrtouint(buf, 10, &size); if (err) return err; if (size > (UINT_MAX / 1024)) return -EINVAL; size *= 1024; dev = comedi_dev_get_from_minor(minor); if (!dev) return -ENODEV; mutex_lock(&dev->mutex); s = comedi_write_subdevice(dev, minor); if (s && (s->subdev_flags & SDF_CMD_WRITE) && s->async) s->async->max_bufsize = size; else err = -EINVAL; mutex_unlock(&dev->mutex); comedi_dev_put(dev); return err ? err : count; } static DEVICE_ATTR_RW(max_write_buffer_kb); static ssize_t write_buffer_kb_show(struct device *csdev, struct device_attribute *attr, char *buf) { unsigned int minor = MINOR(csdev->devt); struct comedi_device *dev; struct comedi_subdevice *s; unsigned int size = 0; dev = comedi_dev_get_from_minor(minor); if (!dev) return -ENODEV; mutex_lock(&dev->mutex); s = comedi_write_subdevice(dev, minor); if (s && (s->subdev_flags & SDF_CMD_WRITE) && s->async) size = s->async->prealloc_bufsz / 1024; mutex_unlock(&dev->mutex); comedi_dev_put(dev); return snprintf(buf, PAGE_SIZE, "%u\n", size); } static ssize_t write_buffer_kb_store(struct device *csdev, struct device_attribute *attr, const char *buf, size_t count) { unsigned int minor = MINOR(csdev->devt); struct comedi_device *dev; struct comedi_subdevice *s; unsigned int size; int err; err = kstrtouint(buf, 10, &size); if (err) return err; if (size > (UINT_MAX / 1024)) return -EINVAL; size *= 1024; dev = comedi_dev_get_from_minor(minor); if (!dev) return -ENODEV; mutex_lock(&dev->mutex); s = comedi_write_subdevice(dev, minor); if (s && (s->subdev_flags & SDF_CMD_WRITE) && s->async) err = resize_async_buffer(dev, s, size); else err = -EINVAL; mutex_unlock(&dev->mutex); comedi_dev_put(dev); return err ? err : count; } static DEVICE_ATTR_RW(write_buffer_kb); static struct attribute *comedi_dev_attrs[] = { &dev_attr_max_read_buffer_kb.attr, &dev_attr_read_buffer_kb.attr, &dev_attr_max_write_buffer_kb.attr, &dev_attr_write_buffer_kb.attr, NULL, }; ATTRIBUTE_GROUPS(comedi_dev); static void __comedi_clear_subdevice_runflags(struct comedi_subdevice *s, unsigned int bits) { s->runflags &= ~bits; } static void __comedi_set_subdevice_runflags(struct comedi_subdevice *s, unsigned int bits) { s->runflags |= bits; } static void comedi_update_subdevice_runflags(struct comedi_subdevice *s, unsigned int mask, unsigned int bits) { unsigned long flags; spin_lock_irqsave(&s->spin_lock, flags); __comedi_clear_subdevice_runflags(s, mask); __comedi_set_subdevice_runflags(s, bits & mask); spin_unlock_irqrestore(&s->spin_lock, flags); } static unsigned int __comedi_get_subdevice_runflags(struct comedi_subdevice *s) { return s->runflags; } static unsigned int comedi_get_subdevice_runflags(struct comedi_subdevice *s) { unsigned long flags; unsigned int runflags; spin_lock_irqsave(&s->spin_lock, flags); runflags = __comedi_get_subdevice_runflags(s); spin_unlock_irqrestore(&s->spin_lock, flags); return runflags; } static bool comedi_is_runflags_running(unsigned int runflags) { return runflags & COMEDI_SRF_RUNNING; } static bool comedi_is_runflags_in_error(unsigned int runflags) { return runflags & COMEDI_SRF_ERROR; } /** * comedi_is_subdevice_running() - Check if async command running on subdevice * @s: COMEDI subdevice. * * Return: %true if an asynchronous COMEDI command is active on the * subdevice, else %false. */ bool comedi_is_subdevice_running(struct comedi_subdevice *s) { unsigned int runflags = comedi_get_subdevice_runflags(s); return comedi_is_runflags_running(runflags); } EXPORT_SYMBOL_GPL(comedi_is_subdevice_running); static bool __comedi_is_subdevice_running(struct comedi_subdevice *s) { unsigned int runflags = __comedi_get_subdevice_runflags(s); return comedi_is_runflags_running(runflags); } bool comedi_can_auto_free_spriv(struct comedi_subdevice *s) { unsigned int runflags = __comedi_get_subdevice_runflags(s); return runflags & COMEDI_SRF_FREE_SPRIV; } /** * comedi_set_spriv_auto_free() - Mark subdevice private data as freeable * @s: COMEDI subdevice. * * Mark the subdevice as having a pointer to private data that can be * automatically freed when the COMEDI device is detached from the low-level * driver. */ void comedi_set_spriv_auto_free(struct comedi_subdevice *s) { __comedi_set_subdevice_runflags(s, COMEDI_SRF_FREE_SPRIV); } EXPORT_SYMBOL_GPL(comedi_set_spriv_auto_free); /** * comedi_alloc_spriv - Allocate memory for the subdevice private data * @s: COMEDI subdevice. * @size: Size of the memory to allocate. * * Allocate memory for the subdevice private data and point @s->private * to it. The memory will be freed automatically when the COMEDI device * is detached from the low-level driver. * * Return: A pointer to the allocated memory @s->private on success. * Return NULL on failure. */ void *comedi_alloc_spriv(struct comedi_subdevice *s, size_t size) { s->private = kzalloc(size, GFP_KERNEL); if (s->private) comedi_set_spriv_auto_free(s); return s->private; } EXPORT_SYMBOL_GPL(comedi_alloc_spriv); /* * This function restores a subdevice to an idle state. */ static void do_become_nonbusy(struct comedi_device *dev, struct comedi_subdevice *s) { struct comedi_async *async = s->async; comedi_update_subdevice_runflags(s, COMEDI_SRF_RUNNING, 0); if (async) { comedi_buf_reset(s); async->inttrig = NULL; kfree(async->cmd.chanlist); async->cmd.chanlist = NULL; s->busy = NULL; wake_up_interruptible_all(&async->wait_head); } else { dev_err(dev->class_dev, "BUG: (?) %s called with async=NULL\n", __func__); s->busy = NULL; } } static int do_cancel(struct comedi_device *dev, struct comedi_subdevice *s) { int ret = 0; if (comedi_is_subdevice_running(s) && s->cancel) ret = s->cancel(dev, s); do_become_nonbusy(dev, s); return ret; } void comedi_device_cancel_all(struct comedi_device *dev) { struct comedi_subdevice *s; int i; if (!dev->attached) return; for (i = 0; i < dev->n_subdevices; i++) { s = &dev->subdevices[i]; if (s->async) do_cancel(dev, s); } } static int is_device_busy(struct comedi_device *dev) { struct comedi_subdevice *s; int i; if (!dev->attached) return 0; for (i = 0; i < dev->n_subdevices; i++) { s = &dev->subdevices[i]; if (s->busy) return 1; if (s->async && comedi_buf_is_mmapped(s)) return 1; } return 0; } /* * COMEDI_DEVCONFIG ioctl * attaches (and configures) or detaches a legacy device * * arg: * pointer to comedi_devconfig structure (NULL if detaching) * * reads: * comedi_devconfig structure (if attaching) * * writes: * nothing */ static int do_devconfig_ioctl(struct comedi_device *dev, struct comedi_devconfig __user *arg) { struct comedi_devconfig it; if (!capable(CAP_SYS_ADMIN)) return -EPERM; if (!arg) { if (is_device_busy(dev)) return -EBUSY; if (dev->attached) { struct module *driver_module = dev->driver->module; comedi_device_detach(dev); module_put(driver_module); } return 0; } if (copy_from_user(&it, arg, sizeof(it))) return -EFAULT; it.board_name[COMEDI_NAMELEN - 1] = 0; if (it.options[COMEDI_DEVCONF_AUX_DATA_LENGTH]) { dev_warn(dev->class_dev, "comedi_config --init_data is deprecated\n"); return -EINVAL; } if (dev->minor >= comedi_num_legacy_minors) /* don't re-use dynamically allocated comedi devices */ return -EBUSY; /* This increments the driver module count on success. */ return comedi_device_attach(dev, &it); } /* * COMEDI_BUFCONFIG ioctl * buffer configuration * * arg: * pointer to comedi_bufconfig structure * * reads: * comedi_bufconfig structure * * writes: * modified comedi_bufconfig structure */ static int do_bufconfig_ioctl(struct comedi_device *dev, struct comedi_bufconfig __user *arg) { struct comedi_bufconfig bc; struct comedi_async *async; struct comedi_subdevice *s; int retval = 0; if (copy_from_user(&bc, arg, sizeof(bc))) return -EFAULT; if (bc.subdevice >= dev->n_subdevices) return -EINVAL; s = &dev->subdevices[bc.subdevice]; async = s->async; if (!async) { dev_dbg(dev->class_dev, "subdevice does not have async capability\n"); bc.size = 0; bc.maximum_size = 0; goto copyback; } if (bc.maximum_size) { if (!capable(CAP_SYS_ADMIN)) return -EPERM; async->max_bufsize = bc.maximum_size; } if (bc.size) { retval = resize_async_buffer(dev, s, bc.size); if (retval < 0) return retval; } bc.size = async->prealloc_bufsz; bc.maximum_size = async->max_bufsize; copyback: if (copy_to_user(arg, &bc, sizeof(bc))) return -EFAULT; return 0; } /* * COMEDI_DEVINFO ioctl * device info * * arg: * pointer to comedi_devinfo structure * * reads: * nothing * * writes: * comedi_devinfo structure */ static int do_devinfo_ioctl(struct comedi_device *dev, struct comedi_devinfo __user *arg, struct file *file) { struct comedi_subdevice *s; struct comedi_devinfo devinfo; memset(&devinfo, 0, sizeof(devinfo)); /* fill devinfo structure */ devinfo.version_code = COMEDI_VERSION_CODE; devinfo.n_subdevs = dev->n_subdevices; strlcpy(devinfo.driver_name, dev->driver->driver_name, COMEDI_NAMELEN); strlcpy(devinfo.board_name, dev->board_name, COMEDI_NAMELEN); s = comedi_file_read_subdevice(file); if (s) devinfo.read_subdevice = s->index; else devinfo.read_subdevice = -1; s = comedi_file_write_subdevice(file); if (s) devinfo.write_subdevice = s->index; else devinfo.write_subdevice = -1; if (copy_to_user(arg, &devinfo, sizeof(devinfo))) return -EFAULT; return 0; } /* * COMEDI_SUBDINFO ioctl * subdevices info * * arg: * pointer to array of comedi_subdinfo structures * * reads: * nothing * * writes: * array of comedi_subdinfo structures */ static int do_subdinfo_ioctl(struct comedi_device *dev, struct comedi_subdinfo __user *arg, void *file) { int ret, i; struct comedi_subdinfo *tmp, *us; struct comedi_subdevice *s; tmp = kcalloc(dev->n_subdevices, sizeof(*tmp), GFP_KERNEL); if (!tmp) return -ENOMEM; /* fill subdinfo structs */ for (i = 0; i < dev->n_subdevices; i++) { s = &dev->subdevices[i]; us = tmp + i; us->type = s->type; us->n_chan = s->n_chan; us->subd_flags = s->subdev_flags; if (comedi_is_subdevice_running(s)) us->subd_flags |= SDF_RUNNING; #define TIMER_nanosec 5 /* backwards compatibility */ us->timer_type = TIMER_nanosec; us->len_chanlist = s->len_chanlist; us->maxdata = s->maxdata; if (s->range_table) { us->range_type = (i << 24) | (0 << 16) | (s->range_table->length); } else { us->range_type = 0; /* XXX */ } if (s->busy) us->subd_flags |= SDF_BUSY; if (s->busy == file) us->subd_flags |= SDF_BUSY_OWNER; if (s->lock) us->subd_flags |= SDF_LOCKED; if (s->lock == file) us->subd_flags |= SDF_LOCK_OWNER; if (!s->maxdata && s->maxdata_list) us->subd_flags |= SDF_MAXDATA; if (s->range_table_list) us->subd_flags |= SDF_RANGETYPE; if (s->do_cmd) us->subd_flags |= SDF_CMD; if (s->insn_bits != &insn_inval) us->insn_bits_support = COMEDI_SUPPORTED; else us->insn_bits_support = COMEDI_UNSUPPORTED; } ret = copy_to_user(arg, tmp, dev->n_subdevices * sizeof(*tmp)); kfree(tmp); return ret ? -EFAULT : 0; } /* * COMEDI_CHANINFO ioctl * subdevice channel info * * arg: * pointer to comedi_chaninfo structure * * reads: * comedi_chaninfo structure * * writes: * array of maxdata values to chaninfo->maxdata_list if requested * array of range table lengths to chaninfo->range_table_list if requested */ static int do_chaninfo_ioctl(struct comedi_device *dev, struct comedi_chaninfo __user *arg) { struct comedi_subdevice *s; struct comedi_chaninfo it; if (copy_from_user(&it, arg, sizeof(it))) return -EFAULT; if (it.subdev >= dev->n_subdevices) return -EINVAL; s = &dev->subdevices[it.subdev]; if (it.maxdata_list) { if (s->maxdata || !s->maxdata_list) return -EINVAL; if (copy_to_user(it.maxdata_list, s->maxdata_list, s->n_chan * sizeof(unsigned int))) return -EFAULT; } if (it.flaglist) return -EINVAL; /* flaglist not supported */ if (it.rangelist) { int i; if (!s->range_table_list) return -EINVAL; for (i = 0; i < s->n_chan; i++) { int x; x = (dev->minor << 28) | (it.subdev << 24) | (i << 16) | (s->range_table_list[i]->length); if (put_user(x, it.rangelist + i)) return -EFAULT; } } return 0; } /* * COMEDI_BUFINFO ioctl * buffer information * * arg: * pointer to comedi_bufinfo structure * * reads: * comedi_bufinfo structure * * writes: * modified comedi_bufinfo structure */ static int do_bufinfo_ioctl(struct comedi_device *dev, struct comedi_bufinfo __user *arg, void *file) { struct comedi_bufinfo bi; struct comedi_subdevice *s; struct comedi_async *async; unsigned int runflags; int retval = 0; bool become_nonbusy = false; if (copy_from_user(&bi, arg, sizeof(bi))) return -EFAULT; if (bi.subdevice >= dev->n_subdevices) return -EINVAL; s = &dev->subdevices[bi.subdevice]; async = s->async; if (!async || s->busy != file) return -EINVAL; runflags = comedi_get_subdevice_runflags(s); if (!(async->cmd.flags & CMDF_WRITE)) { /* command was set up in "read" direction */ if (bi.bytes_read) { comedi_buf_read_alloc(s, bi.bytes_read); bi.bytes_read = comedi_buf_read_free(s, bi.bytes_read); } /* * If nothing left to read, and command has stopped, and * {"read" position not updated or command stopped normally}, * then become non-busy. */ if (comedi_buf_read_n_available(s) == 0 && !comedi_is_runflags_running(runflags) && (bi.bytes_read == 0 || !comedi_is_runflags_in_error(runflags))) { become_nonbusy = true; if (comedi_is_runflags_in_error(runflags)) retval = -EPIPE; } bi.bytes_written = 0; } else { /* command was set up in "write" direction */ if (!comedi_is_runflags_running(runflags)) { bi.bytes_written = 0; become_nonbusy = true; if (comedi_is_runflags_in_error(runflags)) retval = -EPIPE; } else if (bi.bytes_written) { comedi_buf_write_alloc(s, bi.bytes_written); bi.bytes_written = comedi_buf_write_free(s, bi.bytes_written); } bi.bytes_read = 0; } bi.buf_write_count = async->buf_write_count; bi.buf_write_ptr = async->buf_write_ptr; bi.buf_read_count = async->buf_read_count; bi.buf_read_ptr = async->buf_read_ptr; if (become_nonbusy) do_become_nonbusy(dev, s); if (retval) return retval; if (copy_to_user(arg, &bi, sizeof(bi))) return -EFAULT; return 0; } static int check_insn_config_length(struct comedi_insn *insn, unsigned int *data) { if (insn->n < 1) return -EINVAL; switch (data[0]) { case INSN_CONFIG_DIO_OUTPUT: case INSN_CONFIG_DIO_INPUT: case INSN_CONFIG_DISARM: case INSN_CONFIG_RESET: if (insn->n == 1) return 0; break; case INSN_CONFIG_ARM: case INSN_CONFIG_DIO_QUERY: case INSN_CONFIG_BLOCK_SIZE: case INSN_CONFIG_FILTER: case INSN_CONFIG_SERIAL_CLOCK: case INSN_CONFIG_BIDIRECTIONAL_DATA: case INSN_CONFIG_ALT_SOURCE: case INSN_CONFIG_SET_COUNTER_MODE: case INSN_CONFIG_8254_READ_STATUS: case INSN_CONFIG_SET_ROUTING: case INSN_CONFIG_GET_ROUTING: case INSN_CONFIG_GET_PWM_STATUS: case INSN_CONFIG_PWM_SET_PERIOD: case INSN_CONFIG_PWM_GET_PERIOD: if (insn->n == 2) return 0; break; case INSN_CONFIG_SET_GATE_SRC: case INSN_CONFIG_GET_GATE_SRC: case INSN_CONFIG_SET_CLOCK_SRC: case INSN_CONFIG_GET_CLOCK_SRC: case INSN_CONFIG_SET_OTHER_SRC: case INSN_CONFIG_GET_COUNTER_STATUS: case INSN_CONFIG_PWM_SET_H_BRIDGE: case INSN_CONFIG_PWM_GET_H_BRIDGE: case INSN_CONFIG_GET_HARDWARE_BUFFER_SIZE: if (insn->n == 3) return 0; break; case INSN_CONFIG_PWM_OUTPUT: case INSN_CONFIG_ANALOG_TRIG: if (insn->n == 5) return 0; break; case INSN_CONFIG_DIGITAL_TRIG: if (insn->n == 6) return 0; break; case INSN_CONFIG_GET_CMD_TIMING_CONSTRAINTS: if (insn->n >= 4) return 0; break; /* * by default we allow the insn since we don't have checks for * all possible cases yet */ default: pr_warn("No check for data length of config insn id %i is implemented\n", data[0]); pr_warn("Add a check to %s in %s\n", __func__, __FILE__); pr_warn("Assuming n=%i is correct\n", insn->n); return 0; } return -EINVAL; } static int check_insn_device_config_length(struct comedi_insn *insn, unsigned int *data) { if (insn->n < 1) return -EINVAL; switch (data[0]) { case INSN_DEVICE_CONFIG_TEST_ROUTE: case INSN_DEVICE_CONFIG_CONNECT_ROUTE: case INSN_DEVICE_CONFIG_DISCONNECT_ROUTE: if (insn->n == 3) return 0; break; case INSN_DEVICE_CONFIG_GET_ROUTES: /* * Big enough for config_id and the length of the userland * memory buffer. Additional length should be in factors of 2 * to communicate any returned route pairs (source,destination). */ if (insn->n >= 2) return 0; break; } return -EINVAL; } /** * get_valid_routes() - Calls low-level driver get_valid_routes function to * either return a count of valid routes to user, or copy * of list of all valid device routes to buffer in * userspace. * @dev: comedi device pointer * @data: data from user insn call. The length of the data must be >= 2. * data[0] must contain the INSN_DEVICE_CONFIG config_id. * data[1](input) contains the number of _pairs_ for which memory is * allotted from the user. If the user specifies '0', then only * the number of pairs available is returned. * data[1](output) returns either the number of pairs available (if none * where requested) or the number of _pairs_ that are copied back * to the user. * data[2::2] returns each (source, destination) pair. * * Return: -EINVAL if low-level driver does not allocate and return routes as * expected. Returns 0 otherwise. */ static int get_valid_routes(struct comedi_device *dev, unsigned int *data) { data[1] = dev->get_valid_routes(dev, data[1], data + 2); return 0; } static int parse_insn(struct comedi_device *dev, struct comedi_insn *insn, unsigned int *data, void *file) { struct comedi_subdevice *s; int ret = 0; int i; if (insn->insn & INSN_MASK_SPECIAL) { /* a non-subdevice instruction */ switch (insn->insn) { case INSN_GTOD: { struct timespec64 tv; if (insn->n != 2) { ret = -EINVAL; break; } ktime_get_real_ts64(&tv); /* unsigned data safe until 2106 */ data[0] = (unsigned int)tv.tv_sec; data[1] = tv.tv_nsec / NSEC_PER_USEC; ret = 2; break; } case INSN_WAIT: if (insn->n != 1 || data[0] >= 100000) { ret = -EINVAL; break; } udelay(data[0] / 1000); ret = 1; break; case INSN_INTTRIG: if (insn->n != 1) { ret = -EINVAL; break; } if (insn->subdev >= dev->n_subdevices) { dev_dbg(dev->class_dev, "%d not usable subdevice\n", insn->subdev); ret = -EINVAL; break; } s = &dev->subdevices[insn->subdev]; if (!s->async) { dev_dbg(dev->class_dev, "no async\n"); ret = -EINVAL; break; } if (!s->async->inttrig) { dev_dbg(dev->class_dev, "no inttrig\n"); ret = -EAGAIN; break; } ret = s->async->inttrig(dev, s, data[0]); if (ret >= 0) ret = 1; break; case INSN_DEVICE_CONFIG: ret = check_insn_device_config_length(insn, data); if (ret) break; if (data[0] == INSN_DEVICE_CONFIG_GET_ROUTES) { /* * data[1] should be the number of _pairs_ that * the memory can hold. */ data[1] = (insn->n - 2) / 2; ret = get_valid_routes(dev, data); break; } /* other global device config instructions. */ ret = dev->insn_device_config(dev, insn, data); break; default: dev_dbg(dev->class_dev, "invalid insn\n"); ret = -EINVAL; break; } } else { /* a subdevice instruction */ unsigned int maxdata; if (insn->subdev >= dev->n_subdevices) { dev_dbg(dev->class_dev, "subdevice %d out of range\n", insn->subdev); ret = -EINVAL; goto out; } s = &dev->subdevices[insn->subdev]; if (s->type == COMEDI_SUBD_UNUSED) { dev_dbg(dev->class_dev, "%d not usable subdevice\n", insn->subdev); ret = -EIO; goto out; } /* are we locked? (ioctl lock) */ if (s->lock && s->lock != file) { dev_dbg(dev->class_dev, "device locked\n"); ret = -EACCES; goto out; } ret = comedi_check_chanlist(s, 1, &insn->chanspec); if (ret < 0) { ret = -EINVAL; dev_dbg(dev->class_dev, "bad chanspec\n"); goto out; } if (s->busy) { ret = -EBUSY; goto out; } /* This looks arbitrary. It is. */ s->busy = parse_insn; switch (insn->insn) { case INSN_READ: ret = s->insn_read(dev, s, insn, data); if (ret == -ETIMEDOUT) { dev_dbg(dev->class_dev, "subdevice %d read instruction timed out\n", s->index); } break; case INSN_WRITE: maxdata = s->maxdata_list ? s->maxdata_list[CR_CHAN(insn->chanspec)] : s->maxdata; for (i = 0; i < insn->n; ++i) { if (data[i] > maxdata) { ret = -EINVAL; dev_dbg(dev->class_dev, "bad data value(s)\n"); break; } } if (ret == 0) { ret = s->insn_write(dev, s, insn, data); if (ret == -ETIMEDOUT) { dev_dbg(dev->class_dev, "subdevice %d write instruction timed out\n", s->index); } } break; case INSN_BITS: if (insn->n != 2) { ret = -EINVAL; } else { /* * Most drivers ignore the base channel in * insn->chanspec. Fix this here if * the subdevice has <= 32 channels. */ unsigned int orig_mask = data[0]; unsigned int shift = 0; if (s->n_chan <= 32) { shift = CR_CHAN(insn->chanspec); if (shift > 0) { insn->chanspec = 0; data[0] <<= shift; data[1] <<= shift; } } ret = s->insn_bits(dev, s, insn, data); data[0] = orig_mask; if (shift > 0) data[1] >>= shift; } break; case INSN_CONFIG: ret = check_insn_config_length(insn, data); if (ret) break; ret = s->insn_config(dev, s, insn, data); break; default: ret = -EINVAL; break; } s->busy = NULL; } out: return ret; } /* * COMEDI_INSNLIST ioctl * synchronous instruction list * * arg: * pointer to comedi_insnlist structure * * reads: * comedi_insnlist structure * array of comedi_insn structures from insnlist->insns pointer * data (for writes) from insns[].data pointers * * writes: * data (for reads) to insns[].data pointers */ /* arbitrary limits */ #define MAX_SAMPLES 256 static int do_insnlist_ioctl(struct comedi_device *dev, struct comedi_insnlist __user *arg, void *file) { struct comedi_insnlist insnlist; struct comedi_insn *insns = NULL; unsigned int *data = NULL; int i = 0; int ret = 0; if (copy_from_user(&insnlist, arg, sizeof(insnlist))) return -EFAULT; data = kmalloc_array(MAX_SAMPLES, sizeof(unsigned int), GFP_KERNEL); if (!data) { ret = -ENOMEM; goto error; } insns = kcalloc(insnlist.n_insns, sizeof(*insns), GFP_KERNEL); if (!insns) { ret = -ENOMEM; goto error; } if (copy_from_user(insns, insnlist.insns, sizeof(*insns) * insnlist.n_insns)) { dev_dbg(dev->class_dev, "copy_from_user failed\n"); ret = -EFAULT; goto error; } for (i = 0; i < insnlist.n_insns; i++) { if (insns[i].n > MAX_SAMPLES) { dev_dbg(dev->class_dev, "number of samples too large\n"); ret = -EINVAL; goto error; } if (insns[i].insn & INSN_MASK_WRITE) { if (copy_from_user(data, insns[i].data, insns[i].n * sizeof(unsigned int))) { dev_dbg(dev->class_dev, "copy_from_user failed\n"); ret = -EFAULT; goto error; } } ret = parse_insn(dev, insns + i, data, file); if (ret < 0) goto error; if (insns[i].insn & INSN_MASK_READ) { if (copy_to_user(insns[i].data, data, insns[i].n * sizeof(unsigned int))) { dev_dbg(dev->class_dev, "copy_to_user failed\n"); ret = -EFAULT; goto error; } } if (need_resched()) schedule(); } error: kfree(insns); kfree(data); if (ret < 0) return ret; return i; } /* * COMEDI_INSN ioctl * synchronous instruction * * arg: * pointer to comedi_insn structure * * reads: * comedi_insn structure * data (for writes) from insn->data pointer * * writes: * data (for reads) to insn->data pointer */ static int do_insn_ioctl(struct comedi_device *dev, struct comedi_insn __user *arg, void *file) { struct comedi_insn insn; unsigned int *data = NULL; int ret = 0; data = kmalloc_array(MAX_SAMPLES, sizeof(unsigned int), GFP_KERNEL); if (!data) { ret = -ENOMEM; goto error; } if (copy_from_user(&insn, arg, sizeof(insn))) { ret = -EFAULT; goto error; } /* This is where the behavior of insn and insnlist deviate. */ if (insn.n > MAX_SAMPLES) insn.n = MAX_SAMPLES; if (insn.insn & INSN_MASK_WRITE) { if (copy_from_user(data, insn.data, insn.n * sizeof(unsigned int))) { ret = -EFAULT; goto error; } } ret = parse_insn(dev, &insn, data, file); if (ret < 0) goto error; if (insn.insn & INSN_MASK_READ) { if (copy_to_user(insn.data, data, insn.n * sizeof(unsigned int))) { ret = -EFAULT; goto error; } } ret = insn.n; error: kfree(data); return ret; } static int __comedi_get_user_cmd(struct comedi_device *dev, struct comedi_cmd __user *arg, struct comedi_cmd *cmd) { struct comedi_subdevice *s; if (copy_from_user(cmd, arg, sizeof(*cmd))) { dev_dbg(dev->class_dev, "bad cmd address\n"); return -EFAULT; } if (cmd->subdev >= dev->n_subdevices) { dev_dbg(dev->class_dev, "%d no such subdevice\n", cmd->subdev); return -ENODEV; } s = &dev->subdevices[cmd->subdev]; if (s->type == COMEDI_SUBD_UNUSED) { dev_dbg(dev->class_dev, "%d not valid subdevice\n", cmd->subdev); return -EIO; } if (!s->do_cmd || !s->do_cmdtest || !s->async) { dev_dbg(dev->class_dev, "subdevice %d does not support commands\n", cmd->subdev); return -EIO; } /* make sure channel/gain list isn't too long */ if (cmd->chanlist_len > s->len_chanlist) { dev_dbg(dev->class_dev, "channel/gain list too long %d > %d\n", cmd->chanlist_len, s->len_chanlist); return -EINVAL; } /* * Set the CMDF_WRITE flag to the correct state if the subdevice * supports only "read" commands or only "write" commands. */ switch (s->subdev_flags & (SDF_CMD_READ | SDF_CMD_WRITE)) { case SDF_CMD_READ: cmd->flags &= ~CMDF_WRITE; break; case SDF_CMD_WRITE: cmd->flags |= CMDF_WRITE; break; default: break; } return 0; } static int __comedi_get_user_chanlist(struct comedi_device *dev, struct comedi_subdevice *s, unsigned int __user *user_chanlist, struct comedi_cmd *cmd) { unsigned int *chanlist; int ret; cmd->chanlist = NULL; chanlist = memdup_user(user_chanlist, cmd->chanlist_len * sizeof(unsigned int)); if (IS_ERR(chanlist)) return PTR_ERR(chanlist); /* make sure each element in channel/gain list is valid */ ret = comedi_check_chanlist(s, cmd->chanlist_len, chanlist); if (ret < 0) { kfree(chanlist); return ret; } cmd->chanlist = chanlist; return 0; } /* * COMEDI_CMD ioctl * asynchronous acquisition command set-up * * arg: * pointer to comedi_cmd structure * * reads: * comedi_cmd structure * channel/range list from cmd->chanlist pointer * * writes: * possibly modified comedi_cmd structure (when -EAGAIN returned) */ static int do_cmd_ioctl(struct comedi_device *dev, struct comedi_cmd __user *arg, void *file) { struct comedi_cmd cmd; struct comedi_subdevice *s; struct comedi_async *async; unsigned int __user *user_chanlist; int ret; /* get the user's cmd and do some simple validation */ ret = __comedi_get_user_cmd(dev, arg, &cmd); if (ret) return ret; /* save user's chanlist pointer so it can be restored later */ user_chanlist = (unsigned int __user *)cmd.chanlist; s = &dev->subdevices[cmd.subdev]; async = s->async; /* are we locked? (ioctl lock) */ if (s->lock && s->lock != file) { dev_dbg(dev->class_dev, "subdevice locked\n"); return -EACCES; } /* are we busy? */ if (s->busy) { dev_dbg(dev->class_dev, "subdevice busy\n"); return -EBUSY; } /* make sure channel/gain list isn't too short */ if (cmd.chanlist_len < 1) { dev_dbg(dev->class_dev, "channel/gain list too short %u < 1\n", cmd.chanlist_len); return -EINVAL; } async->cmd = cmd; async->cmd.data = NULL; /* load channel/gain list */ ret = __comedi_get_user_chanlist(dev, s, user_chanlist, &async->cmd); if (ret) goto cleanup; ret = s->do_cmdtest(dev, s, &async->cmd); if (async->cmd.flags & CMDF_BOGUS || ret) { dev_dbg(dev->class_dev, "test returned %d\n", ret); cmd = async->cmd; /* restore chanlist pointer before copying back */ cmd.chanlist = (unsigned int __force *)user_chanlist; cmd.data = NULL; if (copy_to_user(arg, &cmd, sizeof(cmd))) { dev_dbg(dev->class_dev, "fault writing cmd\n"); ret = -EFAULT; goto cleanup; } ret = -EAGAIN; goto cleanup; } if (!async->prealloc_bufsz) { ret = -ENOMEM; dev_dbg(dev->class_dev, "no buffer (?)\n"); goto cleanup; } comedi_buf_reset(s); async->cb_mask = COMEDI_CB_BLOCK | COMEDI_CB_CANCEL_MASK; if (async->cmd.flags & CMDF_WAKE_EOS) async->cb_mask |= COMEDI_CB_EOS; comedi_update_subdevice_runflags(s, COMEDI_SRF_BUSY_MASK, COMEDI_SRF_RUNNING); /* * Set s->busy _after_ setting COMEDI_SRF_RUNNING flag to avoid * race with comedi_read() or comedi_write(). */ s->busy = file; ret = s->do_cmd(dev, s); if (ret == 0) return 0; cleanup: do_become_nonbusy(dev, s); return ret; } /* * COMEDI_CMDTEST ioctl * asynchronous acquisition command testing * * arg: * pointer to comedi_cmd structure * * reads: * comedi_cmd structure * channel/range list from cmd->chanlist pointer * * writes: * possibly modified comedi_cmd structure */ static int do_cmdtest_ioctl(struct comedi_device *dev, struct comedi_cmd __user *arg, void *file) { struct comedi_cmd cmd; struct comedi_subdevice *s; unsigned int __user *user_chanlist; int ret; /* get the user's cmd and do some simple validation */ ret = __comedi_get_user_cmd(dev, arg, &cmd); if (ret) return ret; /* save user's chanlist pointer so it can be restored later */ user_chanlist = (unsigned int __user *)cmd.chanlist; s = &dev->subdevices[cmd.subdev]; /* user_chanlist can be NULL for COMEDI_CMDTEST ioctl */ if (user_chanlist) { /* load channel/gain list */ ret = __comedi_get_user_chanlist(dev, s, user_chanlist, &cmd); if (ret) return ret; } ret = s->do_cmdtest(dev, s, &cmd); kfree(cmd.chanlist); /* free kernel copy of user chanlist */ /* restore chanlist pointer before copying back */ cmd.chanlist = (unsigned int __force *)user_chanlist; if (copy_to_user(arg, &cmd, sizeof(cmd))) { dev_dbg(dev->class_dev, "bad cmd address\n"); ret = -EFAULT; } return ret; } /* * COMEDI_LOCK ioctl * lock subdevice * * arg: * subdevice number * * reads: * nothing * * writes: * nothing */ static int do_lock_ioctl(struct comedi_device *dev, unsigned long arg, void *file) { int ret = 0; unsigned long flags; struct comedi_subdevice *s; if (arg >= dev->n_subdevices) return -EINVAL; s = &dev->subdevices[arg]; spin_lock_irqsave(&s->spin_lock, flags); if (s->busy || s->lock) ret = -EBUSY; else s->lock = file; spin_unlock_irqrestore(&s->spin_lock, flags); return ret; } /* * COMEDI_UNLOCK ioctl * unlock subdevice * * arg: * subdevice number * * reads: * nothing * * writes: * nothing */ static int do_unlock_ioctl(struct comedi_device *dev, unsigned long arg, void *file) { struct comedi_subdevice *s; if (arg >= dev->n_subdevices) return -EINVAL; s = &dev->subdevices[arg]; if (s->busy) return -EBUSY; if (s->lock && s->lock != file) return -EACCES; if (s->lock == file) s->lock = NULL; return 0; } /* * COMEDI_CANCEL ioctl * cancel asynchronous acquisition * * arg: * subdevice number * * reads: * nothing * * writes: * nothing */ static int do_cancel_ioctl(struct comedi_device *dev, unsigned long arg, void *file) { struct comedi_subdevice *s; if (arg >= dev->n_subdevices) return -EINVAL; s = &dev->subdevices[arg]; if (!s->async) return -EINVAL; if (!s->busy) return 0; if (s->busy != file) return -EBUSY; return do_cancel(dev, s); } /* * COMEDI_POLL ioctl * instructs driver to synchronize buffers * * arg: * subdevice number * * reads: * nothing * * writes: * nothing */ static int do_poll_ioctl(struct comedi_device *dev, unsigned long arg, void *file) { struct comedi_subdevice *s; if (arg >= dev->n_subdevices) return -EINVAL; s = &dev->subdevices[arg]; if (!s->busy) return 0; if (s->busy != file) return -EBUSY; if (s->poll) return s->poll(dev, s); return -EINVAL; } /* * COMEDI_SETRSUBD ioctl * sets the current "read" subdevice on a per-file basis * * arg: * subdevice number * * reads: * nothing * * writes: * nothing */ static int do_setrsubd_ioctl(struct comedi_device *dev, unsigned long arg, struct file *file) { struct comedi_file *cfp = file->private_data; struct comedi_subdevice *s_old, *s_new; if (arg >= dev->n_subdevices) return -EINVAL; s_new = &dev->subdevices[arg]; s_old = comedi_file_read_subdevice(file); if (s_old == s_new) return 0; /* no change */ if (!(s_new->subdev_flags & SDF_CMD_READ)) return -EINVAL; /* * Check the file isn't still busy handling a "read" command on the * old subdevice (if any). */ if (s_old && s_old->busy == file && s_old->async && !(s_old->async->cmd.flags & CMDF_WRITE)) return -EBUSY; WRITE_ONCE(cfp->read_subdev, s_new); return 0; } /* * COMEDI_SETWSUBD ioctl * sets the current "write" subdevice on a per-file basis * * arg: * subdevice number * * reads: * nothing * * writes: * nothing */ static int do_setwsubd_ioctl(struct comedi_device *dev, unsigned long arg, struct file *file) { struct comedi_file *cfp = file->private_data; struct comedi_subdevice *s_old, *s_new; if (arg >= dev->n_subdevices) return -EINVAL; s_new = &dev->subdevices[arg]; s_old = comedi_file_write_subdevice(file); if (s_old == s_new) return 0; /* no change */ if (!(s_new->subdev_flags & SDF_CMD_WRITE)) return -EINVAL; /* * Check the file isn't still busy handling a "write" command on the * old subdevice (if any). */ if (s_old && s_old->busy == file && s_old->async && (s_old->async->cmd.flags & CMDF_WRITE)) return -EBUSY; WRITE_ONCE(cfp->write_subdev, s_new); return 0; } static long comedi_unlocked_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { unsigned int minor = iminor(file_inode(file)); struct comedi_file *cfp = file->private_data; struct comedi_device *dev = cfp->dev; int rc; mutex_lock(&dev->mutex); /* * Device config is special, because it must work on * an unconfigured device. */ if (cmd == COMEDI_DEVCONFIG) { if (minor >= COMEDI_NUM_BOARD_MINORS) { /* Device config not appropriate on non-board minors. */ rc = -ENOTTY; goto done; } rc = do_devconfig_ioctl(dev, (struct comedi_devconfig __user *)arg); if (rc == 0) { if (arg == 0 && dev->minor >= comedi_num_legacy_minors) { /* * Successfully unconfigured a dynamically * allocated device. Try and remove it. */ if (comedi_clear_board_dev(dev)) { mutex_unlock(&dev->mutex); comedi_free_board_dev(dev); return rc; } } } goto done; } if (!dev->attached) { dev_dbg(dev->class_dev, "no driver attached\n"); rc = -ENODEV; goto done; } switch (cmd) { case COMEDI_BUFCONFIG: rc = do_bufconfig_ioctl(dev, (struct comedi_bufconfig __user *)arg); break; case COMEDI_DEVINFO: rc = do_devinfo_ioctl(dev, (struct comedi_devinfo __user *)arg, file); break; case COMEDI_SUBDINFO: rc = do_subdinfo_ioctl(dev, (struct comedi_subdinfo __user *)arg, file); break; case COMEDI_CHANINFO: rc = do_chaninfo_ioctl(dev, (void __user *)arg); break; case COMEDI_RANGEINFO: rc = do_rangeinfo_ioctl(dev, (void __user *)arg); break; case COMEDI_BUFINFO: rc = do_bufinfo_ioctl(dev, (struct comedi_bufinfo __user *)arg, file); break; case COMEDI_LOCK: rc = do_lock_ioctl(dev, arg, file); break; case COMEDI_UNLOCK: rc = do_unlock_ioctl(dev, arg, file); break; case COMEDI_CANCEL: rc = do_cancel_ioctl(dev, arg, file); break; case COMEDI_CMD: rc = do_cmd_ioctl(dev, (struct comedi_cmd __user *)arg, file); break; case COMEDI_CMDTEST: rc = do_cmdtest_ioctl(dev, (struct comedi_cmd __user *)arg, file); break; case COMEDI_INSNLIST: rc = do_insnlist_ioctl(dev, (struct comedi_insnlist __user *)arg, file); break; case COMEDI_INSN: rc = do_insn_ioctl(dev, (struct comedi_insn __user *)arg, file); break; case COMEDI_POLL: rc = do_poll_ioctl(dev, arg, file); break; case COMEDI_SETRSUBD: rc = do_setrsubd_ioctl(dev, arg, file); break; case COMEDI_SETWSUBD: rc = do_setwsubd_ioctl(dev, arg, file); break; default: rc = -ENOTTY; break; } done: mutex_unlock(&dev->mutex); return rc; } static void comedi_vm_open(struct vm_area_struct *area) { struct comedi_buf_map *bm; bm = area->vm_private_data; comedi_buf_map_get(bm); } static void comedi_vm_close(struct vm_area_struct *area) { struct comedi_buf_map *bm; bm = area->vm_private_data; comedi_buf_map_put(bm); } static int comedi_vm_access(struct vm_area_struct *vma, unsigned long addr, void *buf, int len, int write) { struct comedi_buf_map *bm = vma->vm_private_data; unsigned long offset = addr - vma->vm_start + (vma->vm_pgoff << PAGE_SHIFT); if (len < 0) return -EINVAL; if (len > vma->vm_end - addr) len = vma->vm_end - addr; return comedi_buf_map_access(bm, offset, buf, len, write); } static const struct vm_operations_struct comedi_vm_ops = { .open = comedi_vm_open, .close = comedi_vm_close, .access = comedi_vm_access, }; static int comedi_mmap(struct file *file, struct vm_area_struct *vma) { struct comedi_file *cfp = file->private_data; struct comedi_device *dev = cfp->dev; struct comedi_subdevice *s; struct comedi_async *async; struct comedi_buf_map *bm = NULL; unsigned long start = vma->vm_start; unsigned long size; int n_pages; int i; int retval; /* * 'trylock' avoids circular dependency with current->mm->mmap_sem * and down-reading &dev->attach_lock should normally succeed without * contention unless the device is in the process of being attached * or detached. */ if (!down_read_trylock(&dev->attach_lock)) return -EAGAIN; if (!dev->attached) { dev_dbg(dev->class_dev, "no driver attached\n"); retval = -ENODEV; goto done; } if (vma->vm_flags & VM_WRITE) s = comedi_file_write_subdevice(file); else s = comedi_file_read_subdevice(file); if (!s) { retval = -EINVAL; goto done; } async = s->async; if (!async) { retval = -EINVAL; goto done; } if (vma->vm_pgoff != 0) { dev_dbg(dev->class_dev, "mmap() offset must be 0.\n"); retval = -EINVAL; goto done; } size = vma->vm_end - vma->vm_start; if (size > async->prealloc_bufsz) { retval = -EFAULT; goto done; } if (offset_in_page(size)) { retval = -EFAULT; goto done; } n_pages = vma_pages(vma); /* get reference to current buf map (if any) */ bm = comedi_buf_map_from_subdev_get(s); if (!bm || n_pages > bm->n_pages) { retval = -EINVAL; goto done; } for (i = 0; i < n_pages; ++i) { struct comedi_buf_page *buf = &bm->page_list[i]; if (remap_pfn_range(vma, start, page_to_pfn(virt_to_page(buf->virt_addr)), PAGE_SIZE, PAGE_SHARED)) { retval = -EAGAIN; goto done; } start += PAGE_SIZE; } vma->vm_ops = &comedi_vm_ops; vma->vm_private_data = bm; vma->vm_ops->open(vma); retval = 0; done: up_read(&dev->attach_lock); comedi_buf_map_put(bm); /* put reference to buf map - okay if NULL */ return retval; } static __poll_t comedi_poll(struct file *file, poll_table *wait) { __poll_t mask = 0; struct comedi_file *cfp = file->private_data; struct comedi_device *dev = cfp->dev; struct comedi_subdevice *s, *s_read; down_read(&dev->attach_lock); if (!dev->attached) { dev_dbg(dev->class_dev, "no driver attached\n"); goto done; } s = comedi_file_read_subdevice(file); s_read = s; if (s && s->async) { poll_wait(file, &s->async->wait_head, wait); if (s->busy != file || !comedi_is_subdevice_running(s) || (s->async->cmd.flags & CMDF_WRITE) || comedi_buf_read_n_available(s) > 0) mask |= EPOLLIN | EPOLLRDNORM; } s = comedi_file_write_subdevice(file); if (s && s->async) { unsigned int bps = comedi_bytes_per_sample(s); if (s != s_read) poll_wait(file, &s->async->wait_head, wait); if (s->busy != file || !comedi_is_subdevice_running(s) || !(s->async->cmd.flags & CMDF_WRITE) || comedi_buf_write_n_available(s) >= bps) mask |= EPOLLOUT | EPOLLWRNORM; } done: up_read(&dev->attach_lock); return mask; } static ssize_t comedi_write(struct file *file, const char __user *buf, size_t nbytes, loff_t *offset) { struct comedi_subdevice *s; struct comedi_async *async; unsigned int n, m; ssize_t count = 0; int retval = 0; DECLARE_WAITQUEUE(wait, current); struct comedi_file *cfp = file->private_data; struct comedi_device *dev = cfp->dev; bool become_nonbusy = false; bool attach_locked; unsigned int old_detach_count; /* Protect against device detachment during operation. */ down_read(&dev->attach_lock); attach_locked = true; old_detach_count = dev->detach_count; if (!dev->attached) { dev_dbg(dev->class_dev, "no driver attached\n"); retval = -ENODEV; goto out; } s = comedi_file_write_subdevice(file); if (!s || !s->async) { retval = -EIO; goto out; } async = s->async; if (s->busy != file || !(async->cmd.flags & CMDF_WRITE)) { retval = -EINVAL; goto out; } add_wait_queue(&async->wait_head, &wait); while (count == 0 && !retval) { unsigned int runflags; unsigned int wp, n1, n2; set_current_state(TASK_INTERRUPTIBLE); runflags = comedi_get_subdevice_runflags(s); if (!comedi_is_runflags_running(runflags)) { if (comedi_is_runflags_in_error(runflags)) retval = -EPIPE; if (retval || nbytes) become_nonbusy = true; break; } if (nbytes == 0) break; /* Allocate all free buffer space. */ comedi_buf_write_alloc(s, async->prealloc_bufsz); m = comedi_buf_write_n_allocated(s); n = min_t(size_t, m, nbytes); if (n == 0) { if (file->f_flags & O_NONBLOCK) { retval = -EAGAIN; break; } schedule(); if (signal_pending(current)) { retval = -ERESTARTSYS; break; } if (s->busy != file || !(async->cmd.flags & CMDF_WRITE)) { retval = -EINVAL; break; } continue; } set_current_state(TASK_RUNNING); wp = async->buf_write_ptr; n1 = min(n, async->prealloc_bufsz - wp); n2 = n - n1; m = copy_from_user(async->prealloc_buf + wp, buf, n1); if (m) m += n2; else if (n2) m = copy_from_user(async->prealloc_buf, buf + n1, n2); if (m) { n -= m; retval = -EFAULT; } comedi_buf_write_free(s, n); count += n; nbytes -= n; buf += n; } remove_wait_queue(&async->wait_head, &wait); set_current_state(TASK_RUNNING); if (become_nonbusy && count == 0) { struct comedi_subdevice *new_s; /* * To avoid deadlock, cannot acquire dev->mutex * while dev->attach_lock is held. */ up_read(&dev->attach_lock); attach_locked = false; mutex_lock(&dev->mutex); /* * Check device hasn't become detached behind our back. * Checking dev->detach_count is unchanged ought to be * sufficient (unless there have been 2**32 detaches in the * meantime!), but check the subdevice pointer as well just in * case. * * Also check the subdevice is still in a suitable state to * become non-busy in case it changed behind our back. */ new_s = comedi_file_write_subdevice(file); if (dev->attached && old_detach_count == dev->detach_count && s == new_s && new_s->async == async && s->busy == file && (async->cmd.flags & CMDF_WRITE) && !comedi_is_subdevice_running(s)) do_become_nonbusy(dev, s); mutex_unlock(&dev->mutex); } out: if (attach_locked) up_read(&dev->attach_lock); return count ? count : retval; } static ssize_t comedi_read(struct file *file, char __user *buf, size_t nbytes, loff_t *offset) { struct comedi_subdevice *s; struct comedi_async *async; unsigned int n, m; ssize_t count = 0; int retval = 0; DECLARE_WAITQUEUE(wait, current); struct comedi_file *cfp = file->private_data; struct comedi_device *dev = cfp->dev; unsigned int old_detach_count; bool become_nonbusy = false; bool attach_locked; /* Protect against device detachment during operation. */ down_read(&dev->attach_lock); attach_locked = true; old_detach_count = dev->detach_count; if (!dev->attached) { dev_dbg(dev->class_dev, "no driver attached\n"); retval = -ENODEV; goto out; } s = comedi_file_read_subdevice(file); if (!s || !s->async) { retval = -EIO; goto out; } async = s->async; if (s->busy != file || (async->cmd.flags & CMDF_WRITE)) { retval = -EINVAL; goto out; } add_wait_queue(&async->wait_head, &wait); while (count == 0 && !retval) { unsigned int rp, n1, n2; set_current_state(TASK_INTERRUPTIBLE); m = comedi_buf_read_n_available(s); n = min_t(size_t, m, nbytes); if (n == 0) { unsigned int runflags = comedi_get_subdevice_runflags(s); if (!comedi_is_runflags_running(runflags)) { if (comedi_is_runflags_in_error(runflags)) retval = -EPIPE; if (retval || nbytes) become_nonbusy = true; break; } if (nbytes == 0) break; if (file->f_flags & O_NONBLOCK) { retval = -EAGAIN; break; } schedule(); if (signal_pending(current)) { retval = -ERESTARTSYS; break; } if (s->busy != file || (async->cmd.flags & CMDF_WRITE)) { retval = -EINVAL; break; } continue; } set_current_state(TASK_RUNNING); rp = async->buf_read_ptr; n1 = min(n, async->prealloc_bufsz - rp); n2 = n - n1; m = copy_to_user(buf, async->prealloc_buf + rp, n1); if (m) m += n2; else if (n2) m = copy_to_user(buf + n1, async->prealloc_buf, n2); if (m) { n -= m; retval = -EFAULT; } comedi_buf_read_alloc(s, n); comedi_buf_read_free(s, n); count += n; nbytes -= n; buf += n; } remove_wait_queue(&async->wait_head, &wait); set_current_state(TASK_RUNNING); if (become_nonbusy && count == 0) { struct comedi_subdevice *new_s; /* * To avoid deadlock, cannot acquire dev->mutex * while dev->attach_lock is held. */ up_read(&dev->attach_lock); attach_locked = false; mutex_lock(&dev->mutex); /* * Check device hasn't become detached behind our back. * Checking dev->detach_count is unchanged ought to be * sufficient (unless there have been 2**32 detaches in the * meantime!), but check the subdevice pointer as well just in * case. * * Also check the subdevice is still in a suitable state to * become non-busy in case it changed behind our back. */ new_s = comedi_file_read_subdevice(file); if (dev->attached && old_detach_count == dev->detach_count && s == new_s && new_s->async == async && s->busy == file && !(async->cmd.flags & CMDF_WRITE) && !comedi_is_subdevice_running(s) && comedi_buf_read_n_available(s) == 0) do_become_nonbusy(dev, s); mutex_unlock(&dev->mutex); } out: if (attach_locked) up_read(&dev->attach_lock); return count ? count : retval; } static int comedi_open(struct inode *inode, struct file *file) { const unsigned int minor = iminor(inode); struct comedi_file *cfp; struct comedi_device *dev = comedi_dev_get_from_minor(minor); int rc; if (!dev) { pr_debug("invalid minor number\n"); return -ENODEV; } cfp = kzalloc(sizeof(*cfp), GFP_KERNEL); if (!cfp) return -ENOMEM; cfp->dev = dev; mutex_lock(&dev->mutex); if (!dev->attached && !capable(CAP_SYS_ADMIN)) { dev_dbg(dev->class_dev, "not attached and not CAP_SYS_ADMIN\n"); rc = -ENODEV; goto out; } if (dev->attached && dev->use_count == 0) { if (!try_module_get(dev->driver->module)) { rc = -ENXIO; goto out; } if (dev->open) { rc = dev->open(dev); if (rc < 0) { module_put(dev->driver->module); goto out; } } } dev->use_count++; file->private_data = cfp; comedi_file_reset(file); rc = 0; out: mutex_unlock(&dev->mutex); if (rc) { comedi_dev_put(dev); kfree(cfp); } return rc; } static int comedi_fasync(int fd, struct file *file, int on) { struct comedi_file *cfp = file->private_data; struct comedi_device *dev = cfp->dev; return fasync_helper(fd, file, on, &dev->async_queue); } static int comedi_close(struct inode *inode, struct file *file) { struct comedi_file *cfp = file->private_data; struct comedi_device *dev = cfp->dev; struct comedi_subdevice *s = NULL; int i; mutex_lock(&dev->mutex); if (dev->subdevices) { for (i = 0; i < dev->n_subdevices; i++) { s = &dev->subdevices[i]; if (s->busy == file) do_cancel(dev, s); if (s->lock == file) s->lock = NULL; } } if (dev->attached && dev->use_count == 1) { if (dev->close) dev->close(dev); module_put(dev->driver->module); } dev->use_count--; mutex_unlock(&dev->mutex); comedi_dev_put(dev); kfree(cfp); return 0; } static const struct file_operations comedi_fops = { .owner = THIS_MODULE, .unlocked_ioctl = comedi_unlocked_ioctl, .compat_ioctl = comedi_compat_ioctl, .open = comedi_open, .release = comedi_close, .read = comedi_read, .write = comedi_write, .mmap = comedi_mmap, .poll = comedi_poll, .fasync = comedi_fasync, .llseek = noop_llseek, }; /** * comedi_event() - Handle events for asynchronous COMEDI command * @dev: COMEDI device. * @s: COMEDI subdevice. * Context: in_interrupt() (usually), @s->spin_lock spin-lock not held. * * If an asynchronous COMEDI command is active on the subdevice, process * any %COMEDI_CB_... event flags that have been set, usually by an * interrupt handler. These may change the run state of the asynchronous * command, wake a task, and/or send a %SIGIO signal. */ void comedi_event(struct comedi_device *dev, struct comedi_subdevice *s) { struct comedi_async *async = s->async; unsigned int events; int si_code = 0; unsigned long flags; spin_lock_irqsave(&s->spin_lock, flags); events = async->events; async->events = 0; if (!__comedi_is_subdevice_running(s)) { spin_unlock_irqrestore(&s->spin_lock, flags); return; } if (events & COMEDI_CB_CANCEL_MASK) __comedi_clear_subdevice_runflags(s, COMEDI_SRF_RUNNING); /* * Remember if an error event has occurred, so an error can be * returned the next time the user does a read() or write(). */ if (events & COMEDI_CB_ERROR_MASK) __comedi_set_subdevice_runflags(s, COMEDI_SRF_ERROR); if (async->cb_mask & events) { wake_up_interruptible(&async->wait_head); si_code = async->cmd.flags & CMDF_WRITE ? POLL_OUT : POLL_IN; } spin_unlock_irqrestore(&s->spin_lock, flags); if (si_code) kill_fasync(&dev->async_queue, SIGIO, si_code); } EXPORT_SYMBOL_GPL(comedi_event); /* Note: the ->mutex is pre-locked on successful return */ struct comedi_device *comedi_alloc_board_minor(struct device *hardware_device) { struct comedi_device *dev; struct device *csdev; unsigned int i; dev = kzalloc(sizeof(*dev), GFP_KERNEL); if (!dev) return ERR_PTR(-ENOMEM); comedi_device_init(dev); comedi_set_hw_dev(dev, hardware_device); mutex_lock(&dev->mutex); mutex_lock(&comedi_board_minor_table_lock); for (i = hardware_device ? comedi_num_legacy_minors : 0; i < COMEDI_NUM_BOARD_MINORS; ++i) { if (!comedi_board_minor_table[i]) { comedi_board_minor_table[i] = dev; break; } } mutex_unlock(&comedi_board_minor_table_lock); if (i == COMEDI_NUM_BOARD_MINORS) { mutex_unlock(&dev->mutex); comedi_device_cleanup(dev); comedi_dev_put(dev); dev_err(hardware_device, "ran out of minor numbers for board device files\n"); return ERR_PTR(-EBUSY); } dev->minor = i; csdev = device_create(comedi_class, hardware_device, MKDEV(COMEDI_MAJOR, i), NULL, "comedi%i", i); if (!IS_ERR(csdev)) dev->class_dev = get_device(csdev); /* Note: dev->mutex needs to be unlocked by the caller. */ return dev; } void comedi_release_hardware_device(struct device *hardware_device) { int minor; struct comedi_device *dev; for (minor = comedi_num_legacy_minors; minor < COMEDI_NUM_BOARD_MINORS; minor++) { mutex_lock(&comedi_board_minor_table_lock); dev = comedi_board_minor_table[minor]; if (dev && dev->hw_dev == hardware_device) { comedi_board_minor_table[minor] = NULL; mutex_unlock(&comedi_board_minor_table_lock); comedi_free_board_dev(dev); break; } mutex_unlock(&comedi_board_minor_table_lock); } } int comedi_alloc_subdevice_minor(struct comedi_subdevice *s) { struct comedi_device *dev = s->device; struct device *csdev; unsigned int i; mutex_lock(&comedi_subdevice_minor_table_lock); for (i = 0; i < COMEDI_NUM_SUBDEVICE_MINORS; ++i) { if (!comedi_subdevice_minor_table[i]) { comedi_subdevice_minor_table[i] = s; break; } } mutex_unlock(&comedi_subdevice_minor_table_lock); if (i == COMEDI_NUM_SUBDEVICE_MINORS) { dev_err(dev->class_dev, "ran out of minor numbers for subdevice files\n"); return -EBUSY; } i += COMEDI_NUM_BOARD_MINORS; s->minor = i; csdev = device_create(comedi_class, dev->class_dev, MKDEV(COMEDI_MAJOR, i), NULL, "comedi%i_subd%i", dev->minor, s->index); if (!IS_ERR(csdev)) s->class_dev = csdev; return 0; } void comedi_free_subdevice_minor(struct comedi_subdevice *s) { unsigned int i; if (!s) return; if (s->minor < COMEDI_NUM_BOARD_MINORS || s->minor >= COMEDI_NUM_MINORS) return; i = s->minor - COMEDI_NUM_BOARD_MINORS; mutex_lock(&comedi_subdevice_minor_table_lock); if (s == comedi_subdevice_minor_table[i]) comedi_subdevice_minor_table[i] = NULL; mutex_unlock(&comedi_subdevice_minor_table_lock); if (s->class_dev) { device_destroy(comedi_class, MKDEV(COMEDI_MAJOR, s->minor)); s->class_dev = NULL; } } static void comedi_cleanup_board_minors(void) { struct comedi_device *dev; unsigned int i; for (i = 0; i < COMEDI_NUM_BOARD_MINORS; i++) { dev = comedi_clear_board_minor(i); comedi_free_board_dev(dev); } } static int __init comedi_init(void) { int i; int retval; pr_info("version " COMEDI_RELEASE " - http://www.comedi.org\n"); if (comedi_num_legacy_minors > COMEDI_NUM_BOARD_MINORS) { pr_err("invalid value for module parameter \"comedi_num_legacy_minors\". Valid values are 0 through %i.\n", COMEDI_NUM_BOARD_MINORS); return -EINVAL; } retval = register_chrdev_region(MKDEV(COMEDI_MAJOR, 0), COMEDI_NUM_MINORS, "comedi"); if (retval) return retval; cdev_init(&comedi_cdev, &comedi_fops); comedi_cdev.owner = THIS_MODULE; retval = kobject_set_name(&comedi_cdev.kobj, "comedi"); if (retval) goto out_unregister_chrdev_region; retval = cdev_add(&comedi_cdev, MKDEV(COMEDI_MAJOR, 0), COMEDI_NUM_MINORS); if (retval) goto out_unregister_chrdev_region; comedi_class = class_create(THIS_MODULE, "comedi"); if (IS_ERR(comedi_class)) { retval = PTR_ERR(comedi_class); pr_err("failed to create class\n"); goto out_cdev_del; } comedi_class->dev_groups = comedi_dev_groups; /* create devices files for legacy/manual use */ for (i = 0; i < comedi_num_legacy_minors; i++) { struct comedi_device *dev; dev = comedi_alloc_board_minor(NULL); if (IS_ERR(dev)) { retval = PTR_ERR(dev); goto out_cleanup_board_minors; } /* comedi_alloc_board_minor() locked the mutex */ mutex_unlock(&dev->mutex); } /* XXX requires /proc interface */ comedi_proc_init(); return 0; out_cleanup_board_minors: comedi_cleanup_board_minors(); class_destroy(comedi_class); out_cdev_del: cdev_del(&comedi_cdev); out_unregister_chrdev_region: unregister_chrdev_region(MKDEV(COMEDI_MAJOR, 0), COMEDI_NUM_MINORS); return retval; } module_init(comedi_init); static void __exit comedi_cleanup(void) { comedi_cleanup_board_minors(); class_destroy(comedi_class); cdev_del(&comedi_cdev); unregister_chrdev_region(MKDEV(COMEDI_MAJOR, 0), COMEDI_NUM_MINORS); comedi_proc_cleanup(); } module_exit(comedi_cleanup); MODULE_AUTHOR("http://www.comedi.org"); MODULE_DESCRIPTION("Comedi core module"); MODULE_LICENSE("GPL");
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