On Mon, Feb 05, 2018 at 06:25:27PM -0800, Srivatsa S. Bhat wrote:
> From: Srivatsa S. Bhat <sriva...@csail.mit.edu>
>
> register_blkdev() and __register_chrdev_region() treat the major
> number as an unsigned int. So print it the same way to avoid
> absurd error statements such as:
> "... major requested (-1) is greater than the maximum (511) ..."
> (and also fix off-by-one bugs in the error prints).
>
> While at it, also update the comment describing register_blkdev().
>
> Signed-off-by: Srivatsa S. Bhat <sriva...@csail.mit.edu>
> ---
>
> block/genhd.c | 19 +++++++++++--------
> fs/char_dev.c | 4 ++--
> 2 files changed, 13 insertions(+), 10 deletions(-)
>
> diff --git a/block/genhd.c b/block/genhd.c
> index 88a53c1..21a18e5 100644
> --- a/block/genhd.c
> +++ b/block/genhd.c
> @@ -308,19 +308,22 @@ void blkdev_show(struct seq_file *seqf, off_t offset)
> /**
> * register_blkdev - register a new block device
> *
> - * @major: the requested major device number [1..255]. If @major = 0, try to
> - * allocate any unused major number.
> + * @major: the requested major device number [1..BLKDEV_MAJOR_MAX-1]. If
> + * @major = 0, try to allocate any unused major number.
> * @name: the name of the new block device as a zero terminated string
> *
> * The @name must be unique within the system.
> *
> * The return value depends on the @major input parameter:
> *
> - * - if a major device number was requested in range [1..255] then the
> - * function returns zero on success, or a negative error code
> + * - if a major device number was requested in range [1..BLKDEV_MAJOR_MAX-1]
> + * then the function returns zero on success, or a negative error code
> * - if any unused major number was requested with @major = 0 parameter
> * then the return value is the allocated major number in range
> - * [1..255] or a negative error code otherwise
> + * [1..BLKDEV_MAJOR_MAX-1] or a negative error code otherwise
> + *
> + * See Documentation/admin-guide/devices.txt for the list of allocated
> + * major numbers.
> */
> int register_blkdev(unsigned int major, const char *name)
> {
> @@ -347,8 +350,8 @@ int register_blkdev(unsigned int major, const char *name)
> }
>
> if (major >= BLKDEV_MAJOR_MAX) {
> - pr_err("register_blkdev: major requested (%d) is greater than
> the maximum (%d) for %s\n",
> - major, BLKDEV_MAJOR_MAX, name);
> + pr_err("register_blkdev: major requested (%u) is greater than
> the maximum (%u) for %s\n",
> + major, BLKDEV_MAJOR_MAX-1, name);
>
> ret = -EINVAL;
> goto out;
> @@ -375,7 +378,7 @@ int register_blkdev(unsigned int major, const char *name)
> ret = -EBUSY;
>
> if (ret < 0) {
> - printk("register_blkdev: cannot get major %d for %s\n",
> + printk("register_blkdev: cannot get major %u for %s\n",
> major, name);
> kfree(p);
> }
> diff --git a/fs/char_dev.c b/fs/char_dev.c
> index 33c9385..a279c58 100644
> --- a/fs/char_dev.c
> +++ b/fs/char_dev.c
> @@ -121,8 +121,8 @@ __register_chrdev_region(unsigned int major, unsigned int
> baseminor,
> }
>
> if (major >= CHRDEV_MAJOR_MAX) {
> - pr_err("CHRDEV \"%s\" major requested (%d) is greater than the
> maximum (%d)\n",
> - name, major, CHRDEV_MAJOR_MAX);
> + pr_err("CHRDEV \"%s\" major requested (%u) is greater than the
> maximum (%u)\n",
> + name, major, CHRDEV_MAJOR_MAX-1);
> ret = -EINVAL;
> goto out;
> }
Thanks for both of these patches, if Al doesn't grab them, I will after
4.16-rc1 comes out.
greg k-h
