[5.16] blkcg_gq not found

[65a]

vdev_disk.c:464:39: error: invalid use of undefined type 'struct blkcg_gq'

[65a]

Not clear it's gone, this may be a similar include shuffle

[65a]

Maybe just needs blk-cgroup.h?

[jgottula]

As with #12757, it would have been helpful if you'd used the issue template. This is actually a Linux kernel 5.16 compat breakage, and the issue title should be changed to reflect that.

Anyway. The relevant commit seems to be torvalds/linux@ccdf774, which removes #include <linux/blkdev.h> from <linux/backing-dev>.

Not clear it's gone, this may be a similar include shuffle

So the short version is, yes.

struct blkcg_gq is defined in <linux/blk-cgroup.h>. (It's additionally forward-declared as an opaque struct in <linux/blk_types.h> and <linux/blkdev.h>.)

module/os/linux/zfs/vdev_disk.c, where the definition error now occurs, includes <include/os/linux/kernel/linux/vfs_compat.h>, a local file which itself includes <linux/backing-dev.h>. Prior to the commit referenced above, this would have been sufficient to transitively include <linux/blkdev.h>, which in turn would pull in <linux/blk-cgroup.h>.

Now, however, either vdev_disk.c or vfs_compat.h needs to explicitly #include <linux/blkdev.h> (or possibly <linux/blk-cgroup.h>).

[65a]

See notes on linked issue. Apologies for the confusion, both wrt 5.15 and relevant commit. Issue still seems valid as stated.

[szubersk]

@65a Seems like current master builds with kernel 5.16 perfectly fine. Do you confirm?

[behlendorf]

I'm going to go ahead and close this. This build issue was resolved in master and the 2.1.3 release.