From f33ff110ef31bd250bb8a16cfc4e883aa2b36767 Mon Sep 17 00:00:00 2001 From: "Srivatsa S. Bhat" Date: Mon, 5 Feb 2018 18:25:27 -0800 Subject: [PATCH] block, char_dev: Use correct format specifier for unsigned ints 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 Reviewed-by: Logan Gunthorpe Signed-off-by: Greg Kroah-Hartman --- 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 9656f9e9f99e..dc7e089373b9 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 33c938542160..a279c58fe360 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; }