diff options
Diffstat (limited to 'block')
| -rw-r--r-- | block/genhd.c | 43 |
1 files changed, 4 insertions, 39 deletions
diff --git a/block/genhd.c b/block/genhd.c index f13b7eb0238b..6a5b65c86c4b 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -313,54 +313,19 @@ void unregister_blkdev(unsigned int major, const char *name) EXPORT_SYMBOL(unregister_blkdev); -/** - * blk_mangle_minor - scatter minor numbers apart - * @minor: minor number to mangle - * - * Scatter consecutively allocated @minor number apart if MANGLE_DEVT - * is enabled. Mangling twice gives the original value. - * - * RETURNS: - * Mangled value. - * - * CONTEXT: - * Don't care. - */ -static int blk_mangle_minor(int minor) -{ -#ifdef CONFIG_DEBUG_BLOCK_EXT_DEVT - int i; - - for (i = 0; i < MINORBITS / 2; i++) { - int low = minor & (1 << i); - int high = minor & (1 << (MINORBITS - 1 - i)); - int distance = MINORBITS - 1 - 2 * i; - - minor ^= low | high; /* clear both bits */ - low <<= distance; /* swap the positions */ - high >>= distance; - minor |= low | high; /* and set */ - } -#endif - return minor; -} - int blk_alloc_ext_minor(void) { int idx; idx = ida_alloc_range(&ext_devt_ida, 0, NR_EXT_DEVT, GFP_KERNEL); - if (idx < 0) { - if (idx == -ENOSPC) - return -EBUSY; - return idx; - } - return blk_mangle_minor(idx); + if (idx == -ENOSPC) + return -EBUSY; + return idx; } void blk_free_ext_minor(unsigned int minor) { - ida_free(&ext_devt_ida, blk_mangle_minor(minor)); + ida_free(&ext_devt_ida, minor); } static char *bdevt_str(dev_t devt, char *buf) |