[PATCH] get rid of blkdev_locked_ioctl()
Al Viro [Thu, 18 Sep 2008 19:53:24 +0000 (15:53 -0400)]
Most of that stuff doesn't need BKL at all; expand in the (only) caller,
merge the switch into one there and leave BKL only around the stuff that
might actually need it.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

block/compat_ioctl.c
block/ioctl.c

index 504344d..5b3db06 100644 (file)
@@ -688,12 +688,40 @@ static int compat_blkdev_driver_ioctl(struct block_device *bdev, fmode_t mode,
        return __blkdev_driver_ioctl(bdev, mode, cmd, arg);
 }
 
-static int compat_blkdev_locked_ioctl(struct block_device *bdev,
-                               unsigned cmd, unsigned long arg)
+/* 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;
+       fmode_t mode = file->f_mode;
        struct backing_dev_info *bdi;
+       loff_t size;
+
+       if (file->f_flags & O_NDELAY)
+               mode |= FMODE_NDELAY_NOW;
 
        switch (cmd) {
+       case HDIO_GETGEO:
+               return compat_hdio_getgeo(disk, bdev, compat_ptr(arg));
+       case BLKFLSBUF:
+       case BLKROSET:
+       case BLKDISCARD:
+       /*
+        * 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));
+       case BLKPG:
+               return compat_blkpg_ioctl(inode, file, cmd, compat_ptr(arg));
        case BLKRAGET:
        case BLKFRAGET:
                if (!arg)
@@ -719,67 +747,36 @@ static int compat_blkdev_locked_ioctl(struct block_device *bdev,
                bdi = blk_get_backing_dev_info(bdev);
                if (bdi == NULL)
                        return -ENOTTY;
+               lock_kernel();
                bdi->ra_pages = (arg * 512) / PAGE_CACHE_SIZE;
+               unlock_kernel();
                return 0;
        case BLKGETSIZE:
-               if ((bdev->bd_inode->i_size >> 9) > ~0UL)
+               size = bdev->bd_inode->i_size;
+               if ((size >> 9) > ~0UL)
                        return -EFBIG;
-               return compat_put_ulong(arg, bdev->bd_inode->i_size >> 9);
+               return compat_put_ulong(arg, size >> 9);
 
        case BLKGETSIZE64_32:
                return compat_put_u64(arg, bdev->bd_inode->i_size);
 
        case BLKTRACESETUP32:
-               return compat_blk_trace_setup(bdev, compat_ptr(arg));
+               lock_kernel();
+               ret = compat_blk_trace_setup(bdev, compat_ptr(arg));
+               unlock_kernel();
+               return ret;
        case BLKTRACESTART: /* compatible */
        case BLKTRACESTOP:  /* compatible */
        case BLKTRACETEARDOWN: /* compatible */
-               return blk_trace_ioctl(bdev, cmd, compat_ptr(arg));
-       }
-       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;
-       fmode_t mode = file->f_mode;
-       if (file->f_flags & O_NDELAY)
-               mode |= FMODE_NDELAY_NOW;
-
-       switch (cmd) {
-       case HDIO_GETGEO:
-               return compat_hdio_getgeo(disk, bdev, compat_ptr(arg));
-       case BLKFLSBUF:
-       case BLKROSET:
-       case BLKDISCARD:
-       /*
-        * 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));
-       case BLKPG:
-               return compat_blkpg_ioctl(inode, file, cmd, compat_ptr(arg));
-       }
-
-       lock_kernel();
-       ret = compat_blkdev_locked_ioctl(bdev, cmd, arg);
-       unlock_kernel();
-       if (ret == -ENOIOCTLCMD && disk->fops->compat_ioctl)
-               ret = disk->fops->compat_ioctl(bdev, mode, cmd, arg);
-
-       if (ret != -ENOIOCTLCMD)
+               lock_kernel();
+               ret = blk_trace_ioctl(bdev, cmd, compat_ptr(arg));
+               unlock_kernel();
                return ret;
-
-       return compat_blkdev_driver_ioctl(bdev, mode, cmd, arg);
+       default:
+               if (disk->fops->compat_ioctl)
+                       ret = disk->fops->compat_ioctl(bdev, mode, cmd, arg);
+               if (ret == -ENOIOCTLCMD)
+                       ret = compat_blkdev_driver_ioctl(bdev, mode, cmd, arg);
+               return ret;
+       }
 }
index b4e0abe..bd214cb 100644 (file)
@@ -201,70 +201,6 @@ static int put_u64(unsigned long arg, u64 val)
        return put_user(val, (u64 __user *)arg);
 }
 
-static int blkdev_locked_ioctl(struct file *file, struct block_device *bdev,
-                               unsigned cmd, unsigned long arg)
-{
-       struct backing_dev_info *bdi;
-       int ret, n;
-
-       switch (cmd) {
-       case BLKRAGET:
-       case BLKFRAGET:
-               if (!arg)
-                       return -EINVAL;
-               bdi = blk_get_backing_dev_info(bdev);
-               if (bdi == NULL)
-                       return -ENOTTY;
-               return put_long(arg, (bdi->ra_pages * PAGE_CACHE_SIZE) / 512);
-       case BLKROGET:
-               return put_int(arg, bdev_read_only(bdev) != 0);
-       case BLKBSZGET: /* get the logical block size (cf. BLKSSZGET) */
-               return put_int(arg, block_size(bdev));
-       case BLKSSZGET: /* get block device hardware sector size */
-               return put_int(arg, bdev_hardsect_size(bdev));
-       case BLKSECTGET:
-               return put_ushort(arg, bdev_get_queue(bdev)->max_sectors);
-       case BLKRASET:
-       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 BLKBSZSET:
-               /* set the logical block size */
-               if (!capable(CAP_SYS_ADMIN))
-                       return -EACCES;
-               if (!arg)
-                       return -EINVAL;
-               if (get_user(n, (int __user *) arg))
-                       return -EFAULT;
-               if (bd_claim(bdev, file) < 0)
-                       return -EBUSY;
-               ret = set_blocksize(bdev, n);
-               bd_release(bdev);
-               return ret;
-       case BLKPG:
-               return blkpg_ioctl(bdev, (struct blkpg_ioctl_arg __user *) arg);
-       case BLKRRPART:
-               return blkdev_reread_part(bdev);
-       case BLKGETSIZE:
-               if ((bdev->bd_inode->i_size >> 9) > ~0UL)
-                       return -EFBIG;
-               return put_ulong(arg, bdev->bd_inode->i_size >> 9);
-       case BLKGETSIZE64:
-               return put_u64(arg, bdev->bd_inode->i_size);
-       case BLKTRACESTART:
-       case BLKTRACESTOP:
-       case BLKTRACESETUP:
-       case BLKTRACETEARDOWN:
-               return blk_trace_ioctl(bdev, cmd, (char __user *) arg);
-       }
-       return -ENOIOCTLCMD;
-}
-
 int __blkdev_driver_ioctl(struct block_device *bdev, fmode_t mode,
                        unsigned cmd, unsigned long arg)
 {
@@ -299,6 +235,8 @@ int blkdev_ioctl(struct inode *inode, struct file *file, unsigned cmd,
 {
        struct block_device *bdev = inode->i_bdev;
        struct gendisk *disk = bdev->bd_disk;
+       struct backing_dev_info *bdi;
+       loff_t size;
        int ret, n;
        fmode_t mode = 0;
        if (file) {
@@ -370,14 +308,74 @@ int blkdev_ioctl(struct inode *inode, struct file *file, unsigned cmd,
                        return -EFAULT;
                return 0;
        }
-       }
-
-       lock_kernel();
-       ret = blkdev_locked_ioctl(file, bdev, cmd, arg);
-       unlock_kernel();
-       if (ret != -ENOIOCTLCMD)
+       case BLKRAGET:
+       case BLKFRAGET:
+               if (!arg)
+                       return -EINVAL;
+               bdi = blk_get_backing_dev_info(bdev);
+               if (bdi == NULL)
+                       return -ENOTTY;
+               return put_long(arg, (bdi->ra_pages * PAGE_CACHE_SIZE) / 512);
+       case BLKROGET:
+               return put_int(arg, bdev_read_only(bdev) != 0);
+       case BLKBSZGET: /* get the logical block size (cf. BLKSSZGET) */
+               return put_int(arg, block_size(bdev));
+       case BLKSSZGET: /* get block device hardware sector size */
+               return put_int(arg, bdev_hardsect_size(bdev));
+       case BLKSECTGET:
+               return put_ushort(arg, bdev_get_queue(bdev)->max_sectors);
+       case BLKRASET:
+       case BLKFRASET:
+               if(!capable(CAP_SYS_ADMIN))
+                       return -EACCES;
+               bdi = blk_get_backing_dev_info(bdev);
+               if (bdi == NULL)
+                       return -ENOTTY;
+               lock_kernel();
+               bdi->ra_pages = (arg * 512) / PAGE_CACHE_SIZE;
+               unlock_kernel();
+               return 0;
+       case BLKBSZSET:
+               /* set the logical block size */
+               if (!capable(CAP_SYS_ADMIN))
+                       return -EACCES;
+               if (!arg)
+                       return -EINVAL;
+               if (get_user(n, (int __user *) arg))
+                       return -EFAULT;
+               if (bd_claim(bdev, file) < 0)
+                       return -EBUSY;
+               ret = set_blocksize(bdev, n);
+               bd_release(bdev);
                return ret;
-
-       ret = __blkdev_driver_ioctl(bdev, mode, cmd, arg);
+       case BLKPG:
+               lock_kernel();
+               ret = blkpg_ioctl(bdev, (struct blkpg_ioctl_arg __user *) arg);
+               unlock_kernel();
+               break;
+       case BLKRRPART:
+               lock_kernel();
+               ret = blkdev_reread_part(bdev);
+               unlock_kernel();
+               break;
+       case BLKGETSIZE:
+               size = bdev->bd_inode->i_size;
+               if ((size >> 9) > ~0UL)
+                       return -EFBIG;
+               return put_ulong(arg, size >> 9);
+       case BLKGETSIZE64:
+               return put_u64(arg, bdev->bd_inode->i_size);
+       case BLKTRACESTART:
+       case BLKTRACESTOP:
+       case BLKTRACESETUP:
+       case BLKTRACETEARDOWN:
+               lock_kernel();
+               ret = blk_trace_ioctl(bdev, cmd, (char __user *) arg);
+               unlock_kernel();
+               break;
+       default:
+               ret = __blkdev_driver_ioctl(bdev, mode, cmd, arg);
+       }
+       return ret;
 }
 EXPORT_SYMBOL_GPL(blkdev_ioctl);