mmc: block: Move duplicate check

mmc_blk_ioctl() calls either mmc_blk_ioctl_cmd() or
mmc_blk_ioctl_multi_cmd() and each of these make the same
check. Factor it into a new helper function, call it on
both branches of the switch() statement and save a chunk
of duplicate code.

Cc: Shawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

diff --git a/drivers/mmc/core/block.c b/drivers/mmc/core/block.c
index 274c1ed..9f93acd 100644 (file)
--- a/drivers/mmc/core/block.c
+++ b/drivers/mmc/core/block.c
@@ -564,14 +564,6 @@ static int mmc_blk_ioctl_cmd(struct block_device *bdev,
        int err = 0, ioc_err = 0;
        struct request *req;
 
-       /*
-        * The caller must have CAP_SYS_RAWIO, and must be calling this on the
-        * whole block device, not on a partition.  This prevents overspray
-        * between sibling partitions.
-        */
-       if ((!capable(CAP_SYS_RAWIO)) || (bdev != bdev->bd_contains))
-               return -EPERM;
-
        idata = mmc_blk_ioctl_copy_from_user(ic_ptr);
        if (IS_ERR(idata))
                return PTR_ERR(idata);
@@ -624,14 +616,6 @@ static int mmc_blk_ioctl_multi_cmd(struct block_device *bdev,
        __u64 num_of_cmds;
        struct request *req;
 
-       /*
-        * The caller must have CAP_SYS_RAWIO, and must be calling this on the
-        * whole block device, not on a partition.  This prevents overspray
-        * between sibling partitions.
-        */
-       if ((!capable(CAP_SYS_RAWIO)) || (bdev != bdev->bd_contains))
-               return -EPERM;
-
        if (copy_from_user(&num_of_cmds, &user->num_of_cmds,
                           sizeof(num_of_cmds)))
                return -EFAULT;
@@ -698,14 +682,34 @@ cmd_err:
        return ioc_err ? ioc_err : err;
 }
 
+static int mmc_blk_check_blkdev(struct block_device *bdev)
+{
+       /*
+        * The caller must have CAP_SYS_RAWIO, and must be calling this on the
+        * whole block device, not on a partition.  This prevents overspray
+        * between sibling partitions.
+        */
+       if ((!capable(CAP_SYS_RAWIO)) || (bdev != bdev->bd_contains))
+               return -EPERM;
+       return 0;
+}
+
 static int mmc_blk_ioctl(struct block_device *bdev, fmode_t mode,
        unsigned int cmd, unsigned long arg)
 {
+       int ret;
+
        switch (cmd) {
        case MMC_IOC_CMD:
+               ret = mmc_blk_check_blkdev(bdev);
+               if (ret)
+                       return ret;
                return mmc_blk_ioctl_cmd(bdev,
                                (struct mmc_ioc_cmd __user *)arg);
        case MMC_IOC_MULTI_CMD:
+               ret = mmc_blk_check_blkdev(bdev);
+               if (ret)
+                       return ret;
                return mmc_blk_ioctl_multi_cmd(bdev,
                                (struct mmc_ioc_multi_cmd __user *)arg);
        default: