block: store partition_meta_info.uuid as a string

This will allow other types of UUID to be stored here, aside from true
UUIDs.  This also simplifies code that uses this field, since it's usually
constructed from a, used as a, or compared to other, strings.

Note: A simplistic approach here would be to set uuid_str[36]=0 whenever a
/PARTNROFF option was found to be present.  However, this modifies the
input string, and causes subsequent calls to devt_from_partuuid() not to
see the /PARTNROFF option, which causes different results.  In order to
avoid misleading future maintainers, this parameter is marked const.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Will Drewry <wad@chromium.org>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

1 files changed, 1 insertions, 7 deletions

diff --git a/block/genhd.c b/block/genhd.c
index 6cace663a80..b281f3a2d26 100644
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -743,7 +743,6 @@ void __init printk_all_partitions(void)
                 struct hd_struct *part;
                 char name_buf[BDEVNAME_SIZE];
                 char devt_buf[BDEVT_SIZE];
-                char uuid_buf[PARTITION_META_INFO_UUIDLTH * 2 + 5];
 
                 /*
                  * Don't show empty devices or things that have been
@@ -762,16 +761,11 @@ void __init printk_all_partitions(void)
                 while ((part = disk_part_iter_next(&piter))) {
                         bool is_part0 = part == &disk->part0;
 
-                        uuid_buf[0] = '\0';
-                        if (part->info)
-                                snprintf(uuid_buf, sizeof(uuid_buf), "%pU",
-                                         part->info->uuid);
-
                         printk("%s%s %10llu %s %s", is_part0 ? "" : "  ",
                                bdevt_str(part_devt(part), devt_buf),
                                (unsigned long long)part_nr_sects_read(part) >> 1
                                , disk_name(disk, part->partno, name_buf),
-                               uuid_buf);
+                               part->info ? part->info->uuid : "");
                         if (is_part0) {
                                 if (disk->driverfs_dev != NULL &&
                                     disk->driverfs_dev->driver != NULL)