| /* |
| * comedi/comedi_fops.c |
| * comedi kernel module |
| * |
| * COMEDI - Linux Control and Measurement Device Interface |
| * Copyright (C) 1997-2000 David A. Schleef <ds@schleef.org> |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License as published by |
| * the Free Software Foundation; either version 2 of the License, or |
| * (at your option) any later version. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| */ |
| |
| #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; |
| bool 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: (?) do_become_nonbusy called with async=NULL\n"); |
| 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; |
| /* |
| * 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 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; |
| 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 unsigned int comedi_poll(struct file *file, poll_table *wait) |
| { |
| unsigned int 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 |= POLLIN | POLLRDNORM; |
| } |
| |
| 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 |= POLLOUT | POLLWRNORM; |
| } |
| |
| 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; |
| } |
| |
| 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; |
| } |
| 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"); |