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| author | Mikulas Patocka <mpatocka@redhat.com> | 2023-10-31 19:12:54 +0100 |
|---|---|---|
| committer | Mike Snitzer <snitzer@kernel.org> | 2023-10-31 14:25:06 -0400 |
| commit | 9793c269da6cd339757de6ba5b2c8681b54c99af (patch) | |
| tree | 6c71b9965930e7307d5431500ae3627dbaad1e3b /drivers/md | |
| parent | 070bb43ab01e891db1b742d4ddd7291c7f8d7022 (diff) | |
| download | linux-9793c269da6cd339757de6ba5b2c8681b54c99af.tar.gz linux-9793c269da6cd339757de6ba5b2c8681b54c99af.tar.bz2 linux-9793c269da6cd339757de6ba5b2c8681b54c99af.zip | |
dm crypt: account large pages in cc->n_allocated_pages
The commit 5054e778fcd9c ("dm crypt: allocate compound pages if
possible") changed dm-crypt to use compound pages to improve
performance. Unfortunately, there was an oversight: the allocation of
compound pages was not accounted at all. Normal pages are accounted in
a percpu counter cc->n_allocated_pages and dm-crypt is limited to
allocate at most 2% of memory. Because compound pages were not
accounted at all, dm-crypt could allocate memory over the 2% limit.
Fix this by adding the accounting of compound pages, so that memory
consumption of dm-crypt is properly limited.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Fixes: 5054e778fcd9c ("dm crypt: allocate compound pages if possible")
Cc: stable@vger.kernel.org # v6.5+
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Diffstat (limited to 'drivers/md')
| -rw-r--r-- | drivers/md/dm-crypt.c | 15 |
1 files changed, 12 insertions, 3 deletions
diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c index 4b5c54d0c51a..37dcc113baa1 100644 --- a/drivers/md/dm-crypt.c +++ b/drivers/md/dm-crypt.c @@ -1692,11 +1692,17 @@ retry: order = min(order, remaining_order); while (order > 0) { + if (unlikely(percpu_counter_read_positive(&cc->n_allocated_pages) + + (1 << order) > dm_crypt_pages_per_client)) + goto decrease_order; pages = alloc_pages(gfp_mask | __GFP_NOMEMALLOC | __GFP_NORETRY | __GFP_NOWARN | __GFP_COMP, order); - if (likely(pages != NULL)) + if (likely(pages != NULL)) { + percpu_counter_add(&cc->n_allocated_pages, 1 << order); goto have_pages; + } +decrease_order: order--; } @@ -1734,10 +1740,13 @@ static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone) if (clone->bi_vcnt > 0) { /* bio_for_each_folio_all crashes with an empty bio */ bio_for_each_folio_all(fi, clone) { - if (folio_test_large(fi.folio)) + if (folio_test_large(fi.folio)) { + percpu_counter_sub(&cc->n_allocated_pages, + 1 << folio_order(fi.folio)); folio_put(fi.folio); - else + } else { mempool_free(&fi.folio->page, &cc->page_pool); + } } } } |