From 6a24c71843de1354d3bcc2ce47fd0b3bee936399 Mon Sep 17 00:00:00 2001 From: Milan Broz Date: Tue, 3 Oct 2006 01:15:40 -0700 Subject: [PATCH] dm crypt: use private biosets In the low memory situation dm-crypt needs to use a private mempool of bios to avoid blocking. Signed-off-by: Milan Broz Signed-off-by: Alasdair G Kergon Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/md/dm-crypt.c | 41 +++++++++++++++++++++++++++++------------ 1 file changed, 29 insertions(+), 12 deletions(-) (limited to 'drivers/md') diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c index c34433a6edd0..655d816760e5 100644 --- a/drivers/md/dm-crypt.c +++ b/drivers/md/dm-crypt.c @@ -77,6 +77,7 @@ struct crypt_config { */ mempool_t *io_pool; mempool_t *page_pool; + struct bio_set *bs; /* * crypto related data @@ -95,7 +96,7 @@ struct crypt_config { u8 key[0]; }; -#define MIN_IOS 256 +#define MIN_IOS 16 #define MIN_POOL_PAGES 32 #define MIN_BIO_PAGES 8 @@ -311,6 +312,14 @@ static int crypt_convert(struct crypt_config *cc, return r; } + static void dm_crypt_bio_destructor(struct bio *bio) + { + struct crypt_io *io = bio->bi_private; + struct crypt_config *cc = io->target->private; + + bio_free(bio, cc->bs); + } + /* * Generate a new unfragmented bio with the given size * This should never violate the device limitations @@ -325,18 +334,17 @@ crypt_alloc_buffer(struct crypt_config *cc, unsigned int size, gfp_t gfp_mask = GFP_NOIO | __GFP_HIGHMEM; unsigned int i; - /* - * Use __GFP_NOMEMALLOC to tell the VM to act less aggressively and - * to fail earlier. This is not necessary but increases throughput. - * FIXME: Is this really intelligent? - */ - if (base_bio) - clone = bio_clone(base_bio, GFP_NOIO|__GFP_NOMEMALLOC); - else - clone = bio_alloc(GFP_NOIO|__GFP_NOMEMALLOC, nr_iovecs); + if (base_bio) { + clone = bio_alloc_bioset(GFP_NOIO, base_bio->bi_max_vecs, cc->bs); + __bio_clone(clone, base_bio); + } else + clone = bio_alloc_bioset(GFP_NOIO, nr_iovecs, cc->bs); + if (!clone) return NULL; + clone->bi_destructor = dm_crypt_bio_destructor; + /* if the last bio was not complete, continue where that one ended */ clone->bi_idx = *bio_vec_idx; clone->bi_vcnt = *bio_vec_idx; @@ -517,13 +525,14 @@ static void process_read(struct crypt_io *io) * copy the required bvecs because we need the original * one in order to decrypt the whole bio data *afterwards*. */ - clone = bio_alloc(GFP_NOIO, bio_segments(base_bio)); + clone = bio_alloc_bioset(GFP_NOIO, bio_segments(base_bio), cc->bs); if (unlikely(!clone)) { dec_pending(io, -ENOMEM); return; } clone_init(io, clone); + clone->bi_destructor = dm_crypt_bio_destructor; clone->bi_idx = 0; clone->bi_vcnt = bio_segments(base_bio); clone->bi_size = base_bio->bi_size; @@ -594,7 +603,6 @@ static void process_write(struct crypt_io *io) /* out of memory -> run queues */ if (remaining) blk_congestion_wait(bio_data_dir(clone), HZ/100); - } } @@ -804,6 +812,12 @@ static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv) goto bad4; } + cc->bs = bioset_create(MIN_IOS, MIN_IOS, 4); + if (!cc->bs) { + ti->error = "Cannot allocate crypt bioset"; + goto bad_bs; + } + if (crypto_blkcipher_setkey(tfm, cc->key, key_size) < 0) { ti->error = "Error setting key"; goto bad5; @@ -843,6 +857,8 @@ static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv) return 0; bad5: + bioset_free(cc->bs); +bad_bs: mempool_destroy(cc->page_pool); bad4: mempool_destroy(cc->io_pool); @@ -862,6 +878,7 @@ static void crypt_dtr(struct dm_target *ti) { struct crypt_config *cc = (struct crypt_config *) ti->private; + bioset_free(cc->bs); mempool_destroy(cc->page_pool); mempool_destroy(cc->io_pool); -- cgit v1.2.3-55-g7522