mm/z3fold.c: avoid modifying HEADLESS page and minor cleanup

Fix erroneous z3fold header access in a HEADLESS page in reclaim
function, and change one remaining direct handle-to-buddy conversion to
use the appropriate helper.

Link: http://lkml.kernel.org/r/5748706F.9020208@gmail.com
Signed-off-by: Vitaly Wool <vitalywool@gmail.com>
Reviewed-by: Dan Streetman <ddstreet@ieee.org>
Cc: Seth Jennings <sjenning@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Vitaly Wool 2016-06-03 14:55:47 -07:00 committed by Linus Torvalds
parent 3a06bb78ce
commit 43afc19417

View File

@ -412,7 +412,7 @@ static void z3fold_free(struct z3fold_pool *pool, unsigned long handle)
/* HEADLESS page stored */
bud = HEADLESS;
} else {
bud = (handle - zhdr->first_num) & BUDDY_MASK;
bud = handle_to_buddy(handle);
switch (bud) {
case FIRST:
@ -572,15 +572,19 @@ next:
pool->pages_nr--;
spin_unlock(&pool->lock);
return 0;
} else if (zhdr->first_chunks != 0 &&
zhdr->last_chunks != 0 && zhdr->middle_chunks != 0) {
/* Full, add to buddied list */
list_add(&zhdr->buddy, &pool->buddied);
} else if (!test_bit(PAGE_HEADLESS, &page->private)) {
z3fold_compact_page(zhdr);
/* add to unbuddied list */
freechunks = num_free_chunks(zhdr);
list_add(&zhdr->buddy, &pool->unbuddied[freechunks]);
} else if (!test_bit(PAGE_HEADLESS, &page->private)) {
if (zhdr->first_chunks != 0 &&
zhdr->last_chunks != 0 &&
zhdr->middle_chunks != 0) {
/* Full, add to buddied list */
list_add(&zhdr->buddy, &pool->buddied);
} else {
z3fold_compact_page(zhdr);
/* add to unbuddied list */
freechunks = num_free_chunks(zhdr);
list_add(&zhdr->buddy,
&pool->unbuddied[freechunks]);
}
}
/* add to beginning of LRU */