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path: root/drivers/char/raw.c
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Diffstat (limited to 'drivers/char/raw.c')
-rw-r--r--drivers/char/raw.c322
1 files changed, 191 insertions, 131 deletions
diff --git a/drivers/char/raw.c b/drivers/char/raw.c
index 64acd05f71c..0102dc78860 100644
--- a/drivers/char/raw.c
+++ b/drivers/char/raw.c
@@ -19,7 +19,9 @@
#include <linux/cdev.h>
#include <linux/device.h>
#include <linux/mutex.h>
-#include <linux/smp_lock.h>
+#include <linux/gfp.h>
+#include <linux/compat.h>
+#include <linux/vmalloc.h>
#include <asm/uaccess.h>
@@ -29,10 +31,15 @@ struct raw_device_data {
};
static struct class *raw_class;
-static struct raw_device_data raw_devices[MAX_RAW_MINORS];
+static struct raw_device_data *raw_devices;
static DEFINE_MUTEX(raw_mutex);
static const struct file_operations raw_ctl_fops; /* forward declaration */
+static int max_raw_minors = MAX_RAW_MINORS;
+
+module_param(max_raw_minors, int, 0);
+MODULE_PARM_DESC(max_raw_minors, "Maximum number of raw devices (1-65536)");
+
/*
* Open/close code for raw IO.
*
@@ -54,7 +61,6 @@ static int raw_open(struct inode *inode, struct file *filp)
return 0;
}
- lock_kernel();
mutex_lock(&raw_mutex);
/*
@@ -65,32 +71,25 @@ static int raw_open(struct inode *inode, struct file *filp)
if (!bdev)
goto out;
igrab(bdev->bd_inode);
- err = blkdev_get(bdev, filp->f_mode);
+ err = blkdev_get(bdev, filp->f_mode | FMODE_EXCL, raw_open);
if (err)
goto out;
- err = bd_claim(bdev, raw_open);
- if (err)
- goto out1;
err = set_blocksize(bdev, bdev_logical_block_size(bdev));
if (err)
- goto out2;
+ goto out1;
filp->f_flags |= O_DIRECT;
filp->f_mapping = bdev->bd_inode->i_mapping;
if (++raw_devices[minor].inuse == 1)
- filp->f_path.dentry->d_inode->i_mapping =
+ file_inode(filp)->i_mapping =
bdev->bd_inode->i_mapping;
filp->private_data = bdev;
mutex_unlock(&raw_mutex);
- unlock_kernel();
return 0;
-out2:
- bd_release(bdev);
out1:
- blkdev_put(bdev, filp->f_mode);
+ blkdev_put(bdev, filp->f_mode | FMODE_EXCL);
out:
mutex_unlock(&raw_mutex);
- unlock_kernel();
return err;
}
@@ -112,156 +111,204 @@ static int raw_release(struct inode *inode, struct file *filp)
}
mutex_unlock(&raw_mutex);
- bd_release(bdev);
- blkdev_put(bdev, filp->f_mode);
+ blkdev_put(bdev, filp->f_mode | FMODE_EXCL);
return 0;
}
/*
* Forward ioctls to the underlying block device.
*/
-static int
-raw_ioctl(struct inode *inode, struct file *filp,
- unsigned int command, unsigned long arg)
+static long
+raw_ioctl(struct file *filp, unsigned int command, unsigned long arg)
{
struct block_device *bdev = filp->private_data;
-
return blkdev_ioctl(bdev, 0, command, arg);
}
-static void bind_device(struct raw_config_request *rq)
+static int bind_set(int number, u64 major, u64 minor)
+{
+ dev_t dev = MKDEV(major, minor);
+ struct raw_device_data *rawdev;
+ int err = 0;
+
+ if (number <= 0 || number >= max_raw_minors)
+ return -EINVAL;
+
+ if (MAJOR(dev) != major || MINOR(dev) != minor)
+ return -EINVAL;
+
+ rawdev = &raw_devices[number];
+
+ /*
+ * This is like making block devices, so demand the
+ * same capability
+ */
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ /*
+ * For now, we don't need to check that the underlying
+ * block device is present or not: we can do that when
+ * the raw device is opened. Just check that the
+ * major/minor numbers make sense.
+ */
+
+ if (MAJOR(dev) == 0 && dev != 0)
+ return -EINVAL;
+
+ mutex_lock(&raw_mutex);
+ if (rawdev->inuse) {
+ mutex_unlock(&raw_mutex);
+ return -EBUSY;
+ }
+ if (rawdev->binding) {
+ bdput(rawdev->binding);
+ module_put(THIS_MODULE);
+ }
+ if (!dev) {
+ /* unbind */
+ rawdev->binding = NULL;
+ device_destroy(raw_class, MKDEV(RAW_MAJOR, number));
+ } else {
+ rawdev->binding = bdget(dev);
+ if (rawdev->binding == NULL) {
+ err = -ENOMEM;
+ } else {
+ dev_t raw = MKDEV(RAW_MAJOR, number);
+ __module_get(THIS_MODULE);
+ device_destroy(raw_class, raw);
+ device_create(raw_class, NULL, raw, NULL,
+ "raw%d", number);
+ }
+ }
+ mutex_unlock(&raw_mutex);
+ return err;
+}
+
+static int bind_get(int number, dev_t *dev)
{
- device_destroy(raw_class, MKDEV(RAW_MAJOR, rq->raw_minor));
- device_create(raw_class, NULL, MKDEV(RAW_MAJOR, rq->raw_minor), NULL,
- "raw%d", rq->raw_minor);
+ struct raw_device_data *rawdev;
+ struct block_device *bdev;
+
+ if (number <= 0 || number >= max_raw_minors)
+ return -EINVAL;
+
+ rawdev = &raw_devices[number];
+
+ mutex_lock(&raw_mutex);
+ bdev = rawdev->binding;
+ *dev = bdev ? bdev->bd_dev : 0;
+ mutex_unlock(&raw_mutex);
+ return 0;
}
/*
* Deal with ioctls against the raw-device control interface, to bind
* and unbind other raw devices.
*/
-static int raw_ctl_ioctl(struct inode *inode, struct file *filp,
- unsigned int command, unsigned long arg)
+static long raw_ctl_ioctl(struct file *filp, unsigned int command,
+ unsigned long arg)
{
struct raw_config_request rq;
- struct raw_device_data *rawdev;
- int err = 0;
+ dev_t dev;
+ int err;
switch (command) {
case RAW_SETBIND:
+ if (copy_from_user(&rq, (void __user *) arg, sizeof(rq)))
+ return -EFAULT;
+
+ return bind_set(rq.raw_minor, rq.block_major, rq.block_minor);
+
case RAW_GETBIND:
+ if (copy_from_user(&rq, (void __user *) arg, sizeof(rq)))
+ return -EFAULT;
- /* First, find out which raw minor we want */
+ err = bind_get(rq.raw_minor, &dev);
+ if (err)
+ return err;
- if (copy_from_user(&rq, (void __user *) arg, sizeof(rq))) {
- err = -EFAULT;
- goto out;
- }
+ rq.block_major = MAJOR(dev);
+ rq.block_minor = MINOR(dev);
- if (rq.raw_minor <= 0 || rq.raw_minor >= MAX_RAW_MINORS) {
- err = -EINVAL;
- goto out;
- }
- rawdev = &raw_devices[rq.raw_minor];
-
- if (command == RAW_SETBIND) {
- dev_t dev;
-
- /*
- * This is like making block devices, so demand the
- * same capability
- */
- if (!capable(CAP_SYS_ADMIN)) {
- err = -EPERM;
- goto out;
- }
-
- /*
- * For now, we don't need to check that the underlying
- * block device is present or not: we can do that when
- * the raw device is opened. Just check that the
- * major/minor numbers make sense.
- */
-
- dev = MKDEV(rq.block_major, rq.block_minor);
- if ((rq.block_major == 0 && rq.block_minor != 0) ||
- MAJOR(dev) != rq.block_major ||
- MINOR(dev) != rq.block_minor) {
- err = -EINVAL;
- goto out;
- }
-
- mutex_lock(&raw_mutex);
- if (rawdev->inuse) {
- mutex_unlock(&raw_mutex);
- err = -EBUSY;
- goto out;
- }
- if (rawdev->binding) {
- bdput(rawdev->binding);
- module_put(THIS_MODULE);
- }
- if (rq.block_major == 0 && rq.block_minor == 0) {
- /* unbind */
- rawdev->binding = NULL;
- device_destroy(raw_class,
- MKDEV(RAW_MAJOR, rq.raw_minor));
- } else {
- rawdev->binding = bdget(dev);
- if (rawdev->binding == NULL)
- err = -ENOMEM;
- else {
- __module_get(THIS_MODULE);
- bind_device(&rq);
- }
- }
- mutex_unlock(&raw_mutex);
- } else {
- struct block_device *bdev;
-
- mutex_lock(&raw_mutex);
- bdev = rawdev->binding;
- if (bdev) {
- rq.block_major = MAJOR(bdev->bd_dev);
- rq.block_minor = MINOR(bdev->bd_dev);
- } else {
- rq.block_major = rq.block_minor = 0;
- }
- mutex_unlock(&raw_mutex);
- if (copy_to_user((void __user *)arg, &rq, sizeof(rq))) {
- err = -EFAULT;
- goto out;
- }
- }
- break;
- default:
- err = -EINVAL;
- break;
+ if (copy_to_user((void __user *)arg, &rq, sizeof(rq)))
+ return -EFAULT;
+
+ return 0;
}
-out:
- return err;
+
+ return -EINVAL;
}
+#ifdef CONFIG_COMPAT
+struct raw32_config_request {
+ compat_int_t raw_minor;
+ compat_u64 block_major;
+ compat_u64 block_minor;
+};
+
+static long raw_ctl_compat_ioctl(struct file *file, unsigned int cmd,
+ unsigned long arg)
+{
+ struct raw32_config_request __user *user_req = compat_ptr(arg);
+ struct raw32_config_request rq;
+ dev_t dev;
+ int err = 0;
+
+ switch (cmd) {
+ case RAW_SETBIND:
+ if (copy_from_user(&rq, user_req, sizeof(rq)))
+ return -EFAULT;
+
+ return bind_set(rq.raw_minor, rq.block_major, rq.block_minor);
+
+ case RAW_GETBIND:
+ if (copy_from_user(&rq, user_req, sizeof(rq)))
+ return -EFAULT;
+
+ err = bind_get(rq.raw_minor, &dev);
+ if (err)
+ return err;
+
+ rq.block_major = MAJOR(dev);
+ rq.block_minor = MINOR(dev);
+
+ if (copy_to_user(user_req, &rq, sizeof(rq)))
+ return -EFAULT;
+
+ return 0;
+ }
+
+ return -EINVAL;
+}
+#endif
+
static const struct file_operations raw_fops = {
- .read = do_sync_read,
- .aio_read = generic_file_aio_read,
- .write = do_sync_write,
- .aio_write = blkdev_aio_write,
- .open = raw_open,
- .release= raw_release,
- .ioctl = raw_ioctl,
- .owner = THIS_MODULE,
+ .read = new_sync_read,
+ .read_iter = generic_file_read_iter,
+ .write = new_sync_write,
+ .write_iter = blkdev_write_iter,
+ .fsync = blkdev_fsync,
+ .open = raw_open,
+ .release = raw_release,
+ .unlocked_ioctl = raw_ioctl,
+ .llseek = default_llseek,
+ .owner = THIS_MODULE,
};
static const struct file_operations raw_ctl_fops = {
- .ioctl = raw_ctl_ioctl,
- .open = raw_open,
- .owner = THIS_MODULE,
+ .unlocked_ioctl = raw_ctl_ioctl,
+#ifdef CONFIG_COMPAT
+ .compat_ioctl = raw_ctl_compat_ioctl,
+#endif
+ .open = raw_open,
+ .owner = THIS_MODULE,
+ .llseek = noop_llseek,
};
static struct cdev raw_cdev;
-static char *raw_devnode(struct device *dev, mode_t *mode)
+static char *raw_devnode(struct device *dev, umode_t *mode)
{
return kasprintf(GFP_KERNEL, "raw/%s", dev_name(dev));
}
@@ -271,14 +318,26 @@ static int __init raw_init(void)
dev_t dev = MKDEV(RAW_MAJOR, 0);
int ret;
- ret = register_chrdev_region(dev, MAX_RAW_MINORS, "raw");
+ if (max_raw_minors < 1 || max_raw_minors > 65536) {
+ printk(KERN_WARNING "raw: invalid max_raw_minors (must be"
+ " between 1 and 65536), using %d\n", MAX_RAW_MINORS);
+ max_raw_minors = MAX_RAW_MINORS;
+ }
+
+ raw_devices = vzalloc(sizeof(struct raw_device_data) * max_raw_minors);
+ if (!raw_devices) {
+ printk(KERN_ERR "Not enough memory for raw device structures\n");
+ ret = -ENOMEM;
+ goto error;
+ }
+
+ ret = register_chrdev_region(dev, max_raw_minors, "raw");
if (ret)
goto error;
cdev_init(&raw_cdev, &raw_fops);
- ret = cdev_add(&raw_cdev, dev, MAX_RAW_MINORS);
+ ret = cdev_add(&raw_cdev, dev, max_raw_minors);
if (ret) {
- kobject_put(&raw_cdev.kobj);
goto error_region;
}
@@ -295,8 +354,9 @@ static int __init raw_init(void)
return 0;
error_region:
- unregister_chrdev_region(dev, MAX_RAW_MINORS);
+ unregister_chrdev_region(dev, max_raw_minors);
error:
+ vfree(raw_devices);
return ret;
}
@@ -305,7 +365,7 @@ static void __exit raw_exit(void)
device_destroy(raw_class, MKDEV(RAW_MAJOR, 0));
class_destroy(raw_class);
cdev_del(&raw_cdev);
- unregister_chrdev_region(MKDEV(RAW_MAJOR, 0), MAX_RAW_MINORS);
+ unregister_chrdev_region(MKDEV(RAW_MAJOR, 0), max_raw_minors);
}
module_init(raw_init);