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-rw-r--r--block/compat_ioctl.c121
1 files changed, 121 insertions, 0 deletions
diff --git a/block/compat_ioctl.c b/block/compat_ioctl.c
new file mode 100644
index 0000000..d20fdb4
--- /dev/null
+++ b/block/compat_ioctl.c
@@ -0,0 +1,121 @@
+#include <linux/blkdev.h>
+#include <linux/blkpg.h>
+#include <linux/blktrace_api.h>
+#include <linux/cdrom.h>
+#include <linux/compat.h>
+#include <linux/elevator.h>
+#include <linux/fd.h>
+#include <linux/hdreg.h>
+#include <linux/syscalls.h>
+#include <linux/smp_lock.h>
+#include <linux/types.h>
+#include <linux/uaccess.h>
+
+static int compat_put_ushort(unsigned long arg, unsigned short val)
+{
+ return put_user(val, (unsigned short __user *)compat_ptr(arg));
+}
+
+static int compat_put_int(unsigned long arg, int val)
+{
+ return put_user(val, (compat_int_t __user *)compat_ptr(arg));
+}
+
+static int compat_put_long(unsigned long arg, long val)
+{
+ return put_user(val, (compat_long_t __user *)compat_ptr(arg));
+}
+
+static int compat_put_ulong(unsigned long arg, compat_ulong_t val)
+{
+ return put_user(val, (compat_ulong_t __user *)compat_ptr(arg));
+}
+
+static int compat_put_u64(unsigned long arg, u64 val)
+{
+ return put_user(val, (compat_u64 __user *)compat_ptr(arg));
+}
+
+#define BLKBSZGET_32 _IOR(0x12, 112, int)
+#define BLKBSZSET_32 _IOW(0x12, 113, int)
+#define BLKGETSIZE64_32 _IOR(0x12, 114, int)
+
+static int compat_blkdev_locked_ioctl(struct inode *inode, struct file *file,
+ struct block_device *bdev,
+ unsigned cmd, unsigned long arg)
+{
+ struct backing_dev_info *bdi;
+
+ switch (cmd) {
+ case BLKRAGET:
+ case BLKFRAGET:
+ if (!arg)
+ return -EINVAL;
+ bdi = blk_get_backing_dev_info(bdev);
+ if (bdi == NULL)
+ return -ENOTTY;
+ return compat_put_long(arg,
+ (bdi->ra_pages * PAGE_CACHE_SIZE) / 512);
+ case BLKROGET: /* compatible */
+ return compat_put_int(arg, bdev_read_only(bdev) != 0);
+ case BLKBSZGET_32: /* get the logical block size (cf. BLKSSZGET) */
+ return compat_put_int(arg, block_size(bdev));
+ case BLKSSZGET: /* get block device hardware sector size */
+ return compat_put_int(arg, bdev_hardsect_size(bdev));
+ case BLKSECTGET:
+ return compat_put_ushort(arg,
+ bdev_get_queue(bdev)->max_sectors);
+ case BLKRASET: /* compatible, but no compat_ptr (!) */
+ case BLKFRASET:
+ if (!capable(CAP_SYS_ADMIN))
+ return -EACCES;
+ bdi = blk_get_backing_dev_info(bdev);
+ if (bdi == NULL)
+ return -ENOTTY;
+ bdi->ra_pages = (arg * 512) / PAGE_CACHE_SIZE;
+ return 0;
+ case BLKGETSIZE:
+ if ((bdev->bd_inode->i_size >> 9) > ~0UL)
+ return -EFBIG;
+ return compat_put_ulong(arg, bdev->bd_inode->i_size >> 9);
+
+ case BLKGETSIZE64_32:
+ return compat_put_u64(arg, bdev->bd_inode->i_size);
+ }
+ return -ENOIOCTLCMD;
+}
+
+/* Most of the generic ioctls are handled in the normal fallback path.
+ This assumes the blkdev's low level compat_ioctl always returns
+ ENOIOCTLCMD for unknown ioctls. */
+long compat_blkdev_ioctl(struct file *file, unsigned cmd, unsigned long arg)
+{
+ int ret = -ENOIOCTLCMD;
+ struct inode *inode = file->f_mapping->host;
+ struct block_device *bdev = inode->i_bdev;
+ struct gendisk *disk = bdev->bd_disk;
+
+ switch (cmd) {
+ case BLKFLSBUF:
+ case BLKROSET:
+ /*
+ * the ones below are implemented in blkdev_locked_ioctl,
+ * but we call blkdev_ioctl, which gets the lock for us
+ */
+ case BLKRRPART:
+ return blkdev_ioctl(inode, file, cmd,
+ (unsigned long)compat_ptr(arg));
+ case BLKBSZSET_32:
+ return blkdev_ioctl(inode, file, BLKBSZSET,
+ (unsigned long)compat_ptr(arg));
+ }
+
+ lock_kernel();
+ ret = compat_blkdev_locked_ioctl(inode, file, bdev, cmd, arg);
+ /* FIXME: why do we assume -> compat_ioctl needs the BKL? */
+ if (ret == -ENOIOCTLCMD && disk->fops->compat_ioctl)
+ ret = disk->fops->compat_ioctl(file, cmd, arg);
+ unlock_kernel();
+
+ return ret;
+}
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