On Wednesday, January 11, 2017 2:47:20 PM CET David Howells wrote: > Arnd Bergmann <a...@arndb.de> wrote: > > > > Is it worth abstracting out in-kernel UUID generation? > > > > Do you mean moving it out of AFS into lib/*.c? I think the 'afs_uuid' > > structure is quite different from other UUID definitions, so that wouldn't > > work. > > afs_uuid is as it is to make it easier to package into the on-wire format, but > I suspect there's no problem with using a completely random UUID instead and > divvying it up the same way.
Maybe like this: 8<----7 >From 9e164f852366750fdd732ae317af9f4a9a04a16e Mon Sep 17 00:00:00 2001 From: Arnd Bergmann <a...@arndb.de> Date: Wed, 11 Jan 2017 16:53:13 +0100 Subject: [PATCH] afs: use random UUID AFS uses a time based UUID to identify the host itself. This requires getting a timestamp which is currently done through the getnstimeofday() interface that we want to eventually get rid of. Instead of replacing it with a ktime based interface, this simply removes the entire function and uses generate_random_uuid() instead, which has a v4 ("completely random") uuid instead of the time based one. Signed-off-by: Arnd Bergmann <a...@arndb.de> diff --git a/fs/afs/main.c b/fs/afs/main.c index f8188feb03ad..9944770849da 100644 --- a/fs/afs/main.c +++ b/fs/afs/main.c @@ -35,49 +35,6 @@ struct afs_uuid afs_uuid; struct workqueue_struct *afs_wq; /* - * get a client UUID - */ -static int __init afs_get_client_UUID(void) -{ - struct timespec ts; - u64 uuidtime; - u16 clockseq; - int ret; - - /* read the MAC address of one of the external interfaces and construct - * a UUID from it */ - ret = afs_get_MAC_address(afs_uuid.node, sizeof(afs_uuid.node)); - if (ret < 0) - return ret; - - getnstimeofday(&ts); - uuidtime = (u64) ts.tv_sec * 1000 * 1000 * 10; - uuidtime += ts.tv_nsec / 100; - uuidtime += AFS_UUID_TO_UNIX_TIME; - afs_uuid.time_low = uuidtime; - afs_uuid.time_mid = uuidtime >> 32; - afs_uuid.time_hi_and_version = (uuidtime >> 48) & AFS_UUID_TIMEHI_MASK; - afs_uuid.time_hi_and_version |= AFS_UUID_VERSION_TIME; - - get_random_bytes(&clockseq, 2); - afs_uuid.clock_seq_low = clockseq; - afs_uuid.clock_seq_hi_and_reserved = - (clockseq >> 8) & AFS_UUID_CLOCKHI_MASK; - afs_uuid.clock_seq_hi_and_reserved |= AFS_UUID_VARIANT_STD; - - _debug("AFS UUID: %08x-%04x-%04x-%02x%02x-%02x%02x%02x%02x%02x%02x", - afs_uuid.time_low, - afs_uuid.time_mid, - afs_uuid.time_hi_and_version, - afs_uuid.clock_seq_hi_and_reserved, - afs_uuid.clock_seq_low, - afs_uuid.node[0], afs_uuid.node[1], afs_uuid.node[2], - afs_uuid.node[3], afs_uuid.node[4], afs_uuid.node[5]); - - return 0; -} - -/* * initialise the AFS client FS module */ static int __init afs_init(void) @@ -86,9 +43,7 @@ static int __init afs_init(void) printk(KERN_INFO "kAFS: Red Hat AFS client v0.1 registering.\n"); - ret = afs_get_client_UUID(); - if (ret < 0) - return ret; + generate_random_uuid((unsigned char *)&afs_uuid); /* create workqueue */ ret = -ENOMEM;