Linux 5.12 update: bio_max_segs() replaces BIO_MAX_PAGES

The BIO_MAX_PAGES macro is being retired in favor of a bio_max_segs()
function that implements the typical MIN(x,y) logic used throughout the
kernel for bounding the allocation, and also the new implementation is
intended to be signed-safe (which the former was not).

Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Coleman Kane <ckane@colemankane.org>
Closes #11765
(cherry picked from commit ffd6978ef5)
Signed-off-by: Jonathon Fernyhough <jonathon@m2x.dev>
This commit is contained in:
Coleman Kane
2021-03-20 01:33:42 -04:00
committed by Tony Hutter
parent 91d5ac85c0
commit 5722dce473
3 changed files with 30 additions and 0 deletions
+5
View File
@@ -593,9 +593,14 @@ retry:
}
/* bio_alloc() with __GFP_WAIT never returns NULL */
#ifdef HAVE_BIO_MAX_SEGS
dr->dr_bio[i] = bio_alloc(GFP_NOIO, bio_max_segs(
abd_nr_pages_off(zio->io_abd, bio_size, abd_offset)));
#else
dr->dr_bio[i] = bio_alloc(GFP_NOIO,
MIN(abd_nr_pages_off(zio->io_abd, bio_size, abd_offset),
BIO_MAX_PAGES));
#endif
if (unlikely(dr->dr_bio[i] == NULL)) {
vdev_disk_dio_free(dr);
return (SET_ERROR(ENOMEM));