[PATCH 4.14 180/228] bcache: allocate meta data pages as compound pages

From: Greg Kroah-Hartman
Date: Thu Aug 20 2020 - 06:52:14 EST


From: Coly Li <colyli@xxxxxxx>

commit 5fe48867856367142d91a82f2cbf7a57a24cbb70 upstream.

There are some meta data of bcache are allocated by multiple pages,
and they are used as bio bv_page for I/Os to the cache device. for
example cache_set->uuids, cache->disk_buckets, journal_write->data,
bset_tree->data.

For such meta data memory, all the allocated pages should be treated
as a single memory block. Then the memory management and underlying I/O
code can treat them more clearly.

This patch adds __GFP_COMP flag to all the location allocating >0 order
pages for the above mentioned meta data. Then their pages are treated
as compound pages now.

Signed-off-by: Coly Li <colyli@xxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/md/bcache/bset.c | 2 +-
drivers/md/bcache/btree.c | 2 +-
drivers/md/bcache/journal.c | 4 ++--
drivers/md/bcache/super.c | 2 +-
4 files changed, 5 insertions(+), 5 deletions(-)

--- a/drivers/md/bcache/bset.c
+++ b/drivers/md/bcache/bset.c
@@ -319,7 +319,7 @@ int bch_btree_keys_alloc(struct btree_ke

b->page_order = page_order;

- t->data = (void *) __get_free_pages(gfp, b->page_order);
+ t->data = (void *) __get_free_pages(__GFP_COMP|gfp, b->page_order);
if (!t->data)
goto err;

--- a/drivers/md/bcache/btree.c
+++ b/drivers/md/bcache/btree.c
@@ -794,7 +794,7 @@ int bch_btree_cache_alloc(struct cache_s
mutex_init(&c->verify_lock);

c->verify_ondisk = (void *)
- __get_free_pages(GFP_KERNEL, ilog2(bucket_pages(c)));
+ __get_free_pages(GFP_KERNEL|__GFP_COMP, ilog2(bucket_pages(c)));

c->verify_data = mca_bucket_alloc(c, &ZERO_KEY, GFP_KERNEL);

--- a/drivers/md/bcache/journal.c
+++ b/drivers/md/bcache/journal.c
@@ -838,8 +838,8 @@ int bch_journal_alloc(struct cache_set *
j->w[1].c = c;

if (!(init_fifo(&j->pin, JOURNAL_PIN, GFP_KERNEL)) ||
- !(j->w[0].data = (void *) __get_free_pages(GFP_KERNEL, JSET_BITS)) ||
- !(j->w[1].data = (void *) __get_free_pages(GFP_KERNEL, JSET_BITS)))
+ !(j->w[0].data = (void *) __get_free_pages(GFP_KERNEL|__GFP_COMP, JSET_BITS)) ||
+ !(j->w[1].data = (void *) __get_free_pages(GFP_KERNEL|__GFP_COMP, JSET_BITS)))
return -ENOMEM;

return 0;
--- a/drivers/md/bcache/super.c
+++ b/drivers/md/bcache/super.c
@@ -1468,7 +1468,7 @@ void bch_cache_set_unregister(struct cac
}

#define alloc_bucket_pages(gfp, c) \
- ((void *) __get_free_pages(__GFP_ZERO|gfp, ilog2(bucket_pages(c))))
+ ((void *) __get_free_pages(__GFP_ZERO|__GFP_COMP|gfp, ilog2(bucket_pages(c))))

struct cache_set *bch_cache_set_alloc(struct cache_sb *sb)
{