| Message ID | 2666833.eM84rj4CYY@wuerfel (mailing list archive) |
|---|---|
| State | Accepted, archived |
| Delegated to: | Mike Snitzer |
| Headers | show |
On Tue, Dec 08 2015 at 10:42am -0500, Arnd Bergmann <arnd@arndb.de> wrote: > The dm verity sec implementation uses do_div for dividing a sector_t, > which is slower than necessary when sector_t is a 32-bit type, and > we now get a warning for this case: > > include/asm-generic/div64.h:224:22: warning: passing argument 1 of '__div64_32' from incompatible pointer type [-Wincompatible-pointer-types] > drivers/md/dm-verity-fec.c:725:6: note: in expansion of macro 'do_div' > if (do_div(f->rounds, f->rsn)) > > This changes the code to use sector_div instead, which does the > right thing and avoids the warning. Thanks, I'll fold this in. (Btw, I did review this use of do_div(): but only to answer whether there was potential for a 64bit divide. I concluded do_div() was fine but didn't look to see the data type for f->rounds was actually sector_t.) -- dm-devel mailing list dm-devel@redhat.com https://www.redhat.com/mailman/listinfo/dm-devel
diff --git a/drivers/md/dm-verity-fec.c b/drivers/md/dm-verity-fec.c index e722ce57520f..1bddaca37e98 100644 --- a/drivers/md/dm-verity-fec.c +++ b/drivers/md/dm-verity-fec.c @@ -722,7 +722,7 @@ int verity_fec_ctr(struct dm_verity *v) } f->rounds = f->blocks; - if (do_div(f->rounds, f->rsn)) + if (sector_div(f->rounds, f->rsn)) f->rounds++; /*
The dm verity sec implementation uses do_div for dividing a sector_t, which is slower than necessary when sector_t is a 32-bit type, and we now get a warning for this case: include/asm-generic/div64.h:224:22: warning: passing argument 1 of '__div64_32' from incompatible pointer type [-Wincompatible-pointer-types] drivers/md/dm-verity-fec.c:725:6: note: in expansion of macro 'do_div' if (do_div(f->rounds, f->rsn)) This changes the code to use sector_div instead, which does the right thing and avoids the warning. Signed-off-by: Arnd Bergmann <arnd@arndb.de> --- drivers/md/dm-verity-fec.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) I believe we had a fix for this in the series that introduced the optimized do_div, but the file got moved around and the fix got lost.