Re: [PATCH v3] Add ioctls to get/set the ext4 superblock uuid.
flat view
From: Arnd Bergmann <arnd@arndb.de>
Date: 2022-07-19 07:31:09
Also in:
linux-ext4, linux-fsdevel
On Tue, Jul 19, 2022 at 8:55 AM Jeremy Bongio [off-list ref] wrote:
This fixes a race between changing the ext4 superblock uuid and operations like mounting, resizing, changing features, etc. Reviewed-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Jeremy Bongio <redacted> --- This pair of ioctls may be implemented in more filesystems in the future, namely XFS.
quoted hunk ↗ jump to hunk
+++ b/fs/ext4/ext4.h@@ -724,6 +724,8 @@ enum { #define EXT4_IOC_GETSTATE _IOW('f', 41, __u32) #define EXT4_IOC_GET_ES_CACHE _IOWR('f', 42, struct fiemap) #define EXT4_IOC_CHECKPOINT _IOW('f', 43, __u32) +#define EXT4_IOC_GETFSUUID _IOR('f', 44, struct fsuuid) +#define EXT4_IOC_SETFSUUID _IOW('f', 44, struct fsuuid)
The implementation looks good to me, but maybe it should be defined in
the UAPI headers in a filesystem-independent way? Having it in a private
header means it will not be available to portable user programs, and will
be hidden from tools like strace that parse the uapi headers to find
ioctl definitions.
Arnd