Linux-2.6.12-rc2v2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 342 insertions, 0 deletions

diff --git a/drivers/char/raw.c b/drivers/char/raw.c
new file mode 100644
index 000000000000..a2e33ec79615
--- /dev/null
+++ b/drivers/char/raw.c
@@ -0,0 +1,342 @@
+/*
+ * linux/drivers/char/raw.c
+ *
+ * Front-end raw character devices.  These can be bound to any block
+ * devices to provide genuine Unix raw character device semantics.
+ *
+ * We reserve minor number 0 for a control interface.  ioctl()s on this
+ * device are used to bind the other minor numbers to block devices.
+ */
+
+#include <linux/init.h>
+#include <linux/fs.h>
+#include <linux/devfs_fs_kernel.h>
+#include <linux/major.h>
+#include <linux/blkdev.h>
+#include <linux/module.h>
+#include <linux/raw.h>
+#include <linux/capability.h>
+#include <linux/uio.h>
+#include <linux/cdev.h>
+#include <linux/device.h>
+
+#include <asm/uaccess.h>
+
+struct raw_device_data {
+        struct block_device *binding;
+        int inuse;
+};
+
+static struct class_simple *raw_class;
+static struct raw_device_data raw_devices[MAX_RAW_MINORS];
+static DECLARE_MUTEX(raw_mutex);
+static struct file_operations raw_ctl_fops;          /* forward declaration */
+
+/*
+ * Open/close code for raw IO.
+ *
+ * We just rewrite the i_mapping for the /dev/raw/rawN file descriptor to
+ * point at the blockdev's address_space and set the file handle to use
+ * O_DIRECT.
+ *
+ * Set the device's soft blocksize to the minimum possible.  This gives the
+ * finest possible alignment and has no adverse impact on performance.
+ */
+static int raw_open(struct inode *inode, struct file *filp)
+{
+        const int minor = iminor(inode);
+        struct block_device *bdev;
+        int err;
+
+        if (minor == 0) {       /* It is the control device */
+                filp->f_op = &raw_ctl_fops;
+                return 0;
+        }
+
+        down(&raw_mutex);
+
+        /*
+         * All we need to do on open is check that the device is bound.
+         */
+        bdev = raw_devices[minor].binding;
+        err = -ENODEV;
+        if (!bdev)
+                goto out;
+        igrab(bdev->bd_inode);
+        err = blkdev_get(bdev, filp->f_mode, 0);
+        if (err)
+                goto out;
+        err = bd_claim(bdev, raw_open);
+        if (err)
+                goto out1;
+        err = set_blocksize(bdev, bdev_hardsect_size(bdev));
+        if (err)
+                goto out2;
+        filp->f_flags |= O_DIRECT;
+        filp->f_mapping = bdev->bd_inode->i_mapping;
+        if (++raw_devices[minor].inuse == 1)
+                filp->f_dentry->d_inode->i_mapping =
+                        bdev->bd_inode->i_mapping;
+        filp->private_data = bdev;
+        up(&raw_mutex);
+        return 0;
+
+out2:
+        bd_release(bdev);
+out1:
+        blkdev_put(bdev);
+out:
+        up(&raw_mutex);
+        return err;
+}
+
+/*
+ * When the final fd which refers to this character-special node is closed, we
+ * make its ->mapping point back at its own i_data.
+ */
+static int raw_release(struct inode *inode, struct file *filp)
+{
+        const int minor= iminor(inode);
+        struct block_device *bdev;
+
+        down(&raw_mutex);
+        bdev = raw_devices[minor].binding;
+        if (--raw_devices[minor].inuse == 0) {
+                /* Here  inode->i_mapping == bdev->bd_inode->i_mapping  */
+                inode->i_mapping = &inode->i_data;
+                inode->i_mapping->backing_dev_info = &default_backing_dev_info;
+        }
+        up(&raw_mutex);
+
+        bd_release(bdev);
+        blkdev_put(bdev);
+        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)
+{
+        struct block_device *bdev = filp->private_data;
+
+        return ioctl_by_bdev(bdev, command, arg);
+}
+
+static void bind_device(struct raw_config_request *rq)
+{
+        class_simple_device_remove(MKDEV(RAW_MAJOR, rq->raw_minor));
+        class_simple_device_add(raw_class, MKDEV(RAW_MAJOR, rq->raw_minor),
+                                      NULL, "raw%d", rq->raw_minor);
+}
+
+/*
+ * 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)
+{
+        struct raw_config_request rq;
+        struct raw_device_data *rawdev;
+        int err = 0;
+
+        switch (command) {
+        case RAW_SETBIND:
+        case RAW_GETBIND:
+
+                /* First, find out which raw minor we want */
+
+                if (copy_from_user(&rq, (void __user *) arg, sizeof(rq))) {
+                        err = -EFAULT;
+                        goto out;
+                }
+
+                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;
+                        }
+
+                        down(&raw_mutex);
+                        if (rawdev->inuse) {
+                                up(&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;
+                                class_simple_device_remove(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);
+                                }
+                        }
+                        up(&raw_mutex);
+                } else {
+                        struct block_device *bdev;
+
+                        down(&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;
+                        }
+                        up(&raw_mutex);
+                        if (copy_to_user((void __user *)arg, &rq, sizeof(rq))) {
+                                err = -EFAULT;
+                                goto out;
+                        }
+                }
+                break;
+        default:
+                err = -EINVAL;
+                break;
+        }
+out:
+        return err;
+}
+
+static ssize_t raw_file_write(struct file *file, const char __user *buf,
+                                   size_t count, loff_t *ppos)
+{
+        struct iovec local_iov = {
+                .iov_base = (char __user *)buf,
+                .iov_len = count
+        };
+
+        return generic_file_write_nolock(file, &local_iov, 1, ppos);
+}
+
+static ssize_t raw_file_aio_write(struct kiocb *iocb, const char __user *buf,
+                                        size_t count, loff_t pos)
+{
+        struct iovec local_iov = {
+                .iov_base = (char __user *)buf,
+                .iov_len = count
+        };
+
+        return generic_file_aio_write_nolock(iocb, &local_iov, 1, &iocb->ki_pos);
+}
+
+
+static struct file_operations raw_fops = {
+        .read   =       generic_file_read,
+        .aio_read =     generic_file_aio_read,
+        .write  =       raw_file_write,
+        .aio_write =    raw_file_aio_write,
+        .open   =       raw_open,
+        .release=       raw_release,
+        .ioctl  =       raw_ioctl,
+        .readv  =       generic_file_readv,
+        .writev =       generic_file_writev,
+        .owner  =       THIS_MODULE,
+};
+
+static struct file_operations raw_ctl_fops = {
+        .ioctl  =       raw_ctl_ioctl,
+        .open   =       raw_open,
+        .owner  =       THIS_MODULE,
+};
+
+static struct cdev raw_cdev = {
+        .kobj   =       {.name = "raw", },
+        .owner  =       THIS_MODULE,
+};
+
+static int __init raw_init(void)
+{
+        int i;
+        dev_t dev = MKDEV(RAW_MAJOR, 0);
+
+        if (register_chrdev_region(dev, MAX_RAW_MINORS, "raw"))
+                goto error;
+
+        cdev_init(&raw_cdev, &raw_fops);
+        if (cdev_add(&raw_cdev, dev, MAX_RAW_MINORS)) {
+                kobject_put(&raw_cdev.kobj);
+                unregister_chrdev_region(dev, MAX_RAW_MINORS);
+                goto error;
+        }
+
+        raw_class = class_simple_create(THIS_MODULE, "raw");
+        if (IS_ERR(raw_class)) {
+                printk(KERN_ERR "Error creating raw class.\n");
+                cdev_del(&raw_cdev);
+                unregister_chrdev_region(dev, MAX_RAW_MINORS);
+                goto error;
+        }
+        class_simple_device_add(raw_class, MKDEV(RAW_MAJOR, 0), NULL, "rawctl");
+
+        devfs_mk_cdev(MKDEV(RAW_MAJOR, 0),
+                      S_IFCHR | S_IRUGO | S_IWUGO,
+                      "raw/rawctl");
+        for (i = 1; i < MAX_RAW_MINORS; i++)
+                devfs_mk_cdev(MKDEV(RAW_MAJOR, i),
+                              S_IFCHR | S_IRUGO | S_IWUGO,
+                              "raw/raw%d", i);
+        return 0;
+
+error:
+        printk(KERN_ERR "error register raw device\n");
+        return 1;
+}
+
+static void __exit raw_exit(void)
+{
+        int i;
+
+        for (i = 1; i < MAX_RAW_MINORS; i++)
+                devfs_remove("raw/raw%d", i);
+        devfs_remove("raw/rawctl");
+        devfs_remove("raw");
+        class_simple_device_remove(MKDEV(RAW_MAJOR, 0));
+        class_simple_destroy(raw_class);
+        cdev_del(&raw_cdev);
+        unregister_chrdev_region(MKDEV(RAW_MAJOR, 0), MAX_RAW_MINORS);
+}
+
+module_init(raw_init);
+module_exit(raw_exit);
+MODULE_LICENSE("GPL");