Hi John, On 2/23/24 18:23, John Groves wrote: >>> + >>> +#define FAMFSIOC_MAGIC 'u' >> This 'u' value should be documented in >> Documentation/userspace-api/ioctl/ioctl-number.rst. >> >> and if possible, you might want to use values like 0x5x or 0x8x >> that don't conflict with the ioctl numbers that are already used >> in the 'u' space. > Will do. I was trying to be too clever there, invoking "mu" for > micron. I might have been unclear about this one. It's OK to use 'u' but the values 1-4 below conflict in the 'u' space: 'u' 00-1F linux/smb_fs.h gone 'u' 20-3F linux/uvcvideo.h USB video class host driver 'u' 40-4f linux/udmabuf.h so if you could use 'u' 50-5f or 'u' 80-8f then those conflicts wouldn't be there. HTH. >>> + >>> +/* famfs file ioctl opcodes */ >>> +#define FAMFSIOC_MAP_CREATE _IOW(FAMFSIOC_MAGIC, 1, struct famfs_ioc_map) >>> +#define FAMFSIOC_MAP_GET _IOR(FAMFSIOC_MAGIC, 2, struct famfs_ioc_map) >>> +#define FAMFSIOC_MAP_GETEXT _IOR(FAMFSIOC_MAGIC, 3, struct famfs_extent) >>> +#define FAMFSIOC_NOP _IO(FAMFSIOC_MAGIC, 4) -- #Randy
