* [PATCH 2/5] blk-crypto-fallback: consolidate static variables
2021-09-13 1:31 [PATCH 0/5] blk-crypto cleanups Eric Biggers
2021-09-13 1:31 ` [PATCH 1/5] blk-crypto-fallback: properly prefix function and struct names Eric Biggers
@ 2021-09-13 1:31 ` Eric Biggers
2021-09-15 7:39 ` Christoph Hellwig
2021-09-13 1:31 ` [PATCH 3/5] blk-crypto: rename keyslot-manager files to blk-crypto-profile Eric Biggers
` (2 subsequent siblings)
4 siblings, 1 reply; 17+ messages in thread
From: Eric Biggers @ 2021-09-13 1:31 UTC (permalink / raw)
To: linux-block; +Cc: linux-mmc, linux-scsi, dm-devel, Satya Tangirala
From: Eric Biggers <ebiggers@google.com>
blk-crypto-fallback.c has many static variables with inconsistent names,
e.g. "blk_crypto_*", "crypto_*", and some unprefixed names. This is
confusing. Consolidate them all into a struct named
"blk_crypto_fallback" so that it's clear what they are.
Signed-off-by: Eric Biggers <ebiggers@google.com>
---
block/blk-crypto-fallback.c | 251 +++++++++++++++++++-----------------
1 file changed, 136 insertions(+), 115 deletions(-)
diff --git a/block/blk-crypto-fallback.c b/block/blk-crypto-fallback.c
index 82b302597b474..a4a444c83fb3c 100644
--- a/block/blk-crypto-fallback.c
+++ b/block/blk-crypto-fallback.c
@@ -21,20 +21,10 @@
#include "blk-crypto-internal.h"
-static unsigned int num_prealloc_bounce_pg = 32;
-module_param(num_prealloc_bounce_pg, uint, 0);
-MODULE_PARM_DESC(num_prealloc_bounce_pg,
- "Number of preallocated bounce pages for the blk-crypto crypto API fallback");
-
-static unsigned int blk_crypto_num_keyslots = 100;
-module_param_named(num_keyslots, blk_crypto_num_keyslots, uint, 0);
-MODULE_PARM_DESC(num_keyslots,
- "Number of keyslots for the blk-crypto crypto API fallback");
-
-static unsigned int num_prealloc_fallback_crypt_ctxs = 128;
-module_param(num_prealloc_fallback_crypt_ctxs, uint, 0);
-MODULE_PARM_DESC(num_prealloc_crypt_fallback_ctxs,
- "Number of preallocated bio fallback crypto contexts for blk-crypto to use during crypto API fallback");
+struct blk_crypto_fallback_keyslot {
+ enum blk_crypto_mode_num crypto_mode;
+ struct crypto_skcipher *tfms[BLK_ENCRYPTION_MODE_MAX];
+};
struct bio_fallback_crypt_ctx {
struct bio_crypt_ctx crypt_ctx;
@@ -57,47 +47,80 @@ struct bio_fallback_crypt_ctx {
};
};
-static struct kmem_cache *bio_fallback_crypt_ctx_cache;
-static mempool_t *bio_fallback_crypt_ctx_pool;
+/* All state for blk-crypto-fallback */
+static struct blk_crypto_fallback {
+ unsigned int num_prealloc_bounce_pg;
+ unsigned int num_keyslots;
+ unsigned int num_prealloc_crypt_ctxs;
-/*
- * Allocating a crypto tfm during I/O can deadlock, so we have to preallocate
- * all of a mode's tfms when that mode starts being used. Since each mode may
- * need all the keyslots at some point, each mode needs its own tfm for each
- * keyslot; thus, a keyslot may contain tfms for multiple modes. However, to
- * match the behavior of real inline encryption hardware (which only supports a
- * single encryption context per keyslot), we only allow one tfm per keyslot to
- * be used at a time - the rest of the unused tfms have their keys cleared.
- */
-static DEFINE_MUTEX(tfms_init_lock);
-static bool tfms_inited[BLK_ENCRYPTION_MODE_MAX];
+ bool initialized;
-static struct blk_crypto_fallback_keyslot {
- enum blk_crypto_mode_num crypto_mode;
- struct crypto_skcipher *tfms[BLK_ENCRYPTION_MODE_MAX];
-} *blk_crypto_keyslots;
+ /*
+ * This is the key we set when evicting a keyslot. This *should* be the
+ * all 0's key, but AES-XTS rejects that key, so we use some random
+ * bytes instead.
+ */
+ u8 blank_key[BLK_CRYPTO_MAX_KEY_SIZE];
-static struct blk_keyslot_manager blk_crypto_ksm;
-static struct workqueue_struct *blk_crypto_wq;
-static mempool_t *blk_crypto_bounce_page_pool;
-static struct bio_set crypto_bio_split;
+ struct bio_set bio_split;
-/*
- * This is the key we set when evicting a keyslot. This *should* be the all 0's
- * key, but AES-XTS rejects that key, so we use some random bytes instead.
- */
-static u8 blank_key[BLK_CRYPTO_MAX_KEY_SIZE];
+ struct blk_keyslot_manager ksm;
+
+ struct workqueue_struct *decrypt_wq;
+
+ struct blk_crypto_fallback_keyslot *keyslots;
+
+ mempool_t *bounce_page_pool;
+ struct kmem_cache *crypt_ctx_cache;
+ mempool_t *crypt_ctx_pool;
+
+ /*
+ * Allocating a crypto tfm during I/O can deadlock, so we have to
+ * preallocate all of a mode's tfms when that mode starts being used.
+ * Since each mode may need all the keyslots at some point, each mode
+ * needs its own tfm for each keyslot; thus, a keyslot may contain tfms
+ * for multiple modes. However, to match the behavior of real inline
+ * encryption hardware (which only supports a single encryption context
+ * per keyslot), we only allow one tfm per keyslot to be used at a time
+ * - the rest of the unused tfms have their keys cleared.
+ */
+ struct mutex tfms_init_lock;
+ bool tfms_inited[BLK_ENCRYPTION_MODE_MAX];
+
+} blk_crypto_fallback = {
+ .num_prealloc_bounce_pg = 32,
+ .num_keyslots = 100,
+ .num_prealloc_crypt_ctxs = 128,
+ .tfms_init_lock =
+ __MUTEX_INITIALIZER(blk_crypto_fallback.tfms_init_lock),
+};
+
+module_param_named(num_prealloc_bounce_pg,
+ blk_crypto_fallback.num_prealloc_bounce_pg, uint, 0);
+MODULE_PARM_DESC(num_prealloc_bounce_pg,
+ "Number of preallocated bounce pages for the blk-crypto crypto API fallback");
+
+module_param_named(num_keyslots, blk_crypto_fallback.num_keyslots, uint, 0);
+MODULE_PARM_DESC(num_keyslots,
+ "Number of keyslots for the blk-crypto crypto API fallback");
+
+module_param_named(num_prealloc_fallback_crypt_ctxs,
+ blk_crypto_fallback.num_prealloc_crypt_ctxs, uint, 0);
+MODULE_PARM_DESC(num_prealloc_crypt_fallback_ctxs,
+ "Number of preallocated bio fallback crypto contexts for blk-crypto to use during crypto API fallback");
static void blk_crypto_fallback_evict_keyslot(unsigned int slot)
{
- struct blk_crypto_fallback_keyslot *slotp = &blk_crypto_keyslots[slot];
+ struct blk_crypto_fallback *fallback = &blk_crypto_fallback;
+ struct blk_crypto_fallback_keyslot *slotp = &fallback->keyslots[slot];
enum blk_crypto_mode_num crypto_mode = slotp->crypto_mode;
int err;
WARN_ON(slotp->crypto_mode == BLK_ENCRYPTION_MODE_INVALID);
/* Clear the key in the skcipher */
- err = crypto_skcipher_setkey(slotp->tfms[crypto_mode], blank_key,
+ err = crypto_skcipher_setkey(slotp->tfms[crypto_mode],
+ fallback->blank_key,
blk_crypto_modes[crypto_mode].keysize);
WARN_ON(err);
slotp->crypto_mode = BLK_ENCRYPTION_MODE_INVALID;
@@ -107,7 +130,8 @@ static int blk_crypto_fallback_keyslot_program(struct blk_keyslot_manager *ksm,
const struct blk_crypto_key *key,
unsigned int slot)
{
- struct blk_crypto_fallback_keyslot *slotp = &blk_crypto_keyslots[slot];
+ struct blk_crypto_fallback *fallback = &blk_crypto_fallback;
+ struct blk_crypto_fallback_keyslot *slotp = &fallback->keyslots[slot];
const enum blk_crypto_mode_num crypto_mode =
key->crypto_cfg.crypto_mode;
int err;
@@ -134,16 +158,6 @@ static int blk_crypto_fallback_keyslot_evict(struct blk_keyslot_manager *ksm,
return 0;
}
-/*
- * The crypto API fallback KSM ops - only used for a bio when it specifies a
- * blk_crypto_key that was not supported by the device's inline encryption
- * hardware.
- */
-static const struct blk_ksm_ll_ops blk_crypto_ksm_ll_ops = {
- .keyslot_program = blk_crypto_fallback_keyslot_program,
- .keyslot_evict = blk_crypto_fallback_keyslot_evict,
-};
-
static void blk_crypto_fallback_encrypt_endio(struct bio *enc_bio)
{
struct bio *src_bio = enc_bio->bi_private;
@@ -151,7 +165,7 @@ static void blk_crypto_fallback_encrypt_endio(struct bio *enc_bio)
for (i = 0; i < enc_bio->bi_vcnt; i++)
mempool_free(enc_bio->bi_io_vec[i].bv_page,
- blk_crypto_bounce_page_pool);
+ blk_crypto_fallback.bounce_page_pool);
src_bio->bi_status = enc_bio->bi_status;
@@ -195,7 +209,7 @@ blk_crypto_fallback_alloc_cipher_req(struct blk_ksm_keyslot *slot,
const struct blk_crypto_fallback_keyslot *slotp;
int keyslot_idx = blk_ksm_get_slot_idx(slot);
- slotp = &blk_crypto_keyslots[keyslot_idx];
+ slotp = &blk_crypto_fallback.keyslots[keyslot_idx];
ciph_req = skcipher_request_alloc(slotp->tfms[slotp->crypto_mode],
GFP_NOIO);
if (!ciph_req)
@@ -227,7 +241,7 @@ static bool blk_crypto_fallback_split_bio_if_needed(struct bio **bio_ptr)
struct bio *split_bio;
split_bio = bio_split(bio, num_sectors, GFP_NOIO,
- &crypto_bio_split);
+ &blk_crypto_fallback.bio_split);
if (!split_bio) {
bio->bi_status = BLK_STS_RESOURCE;
return false;
@@ -263,6 +277,7 @@ static void blk_crypto_dun_to_iv(const u64 dun[BLK_CRYPTO_DUN_ARRAY_SIZE],
*/
static bool blk_crypto_fallback_encrypt_bio(struct bio **bio_ptr)
{
+ struct blk_crypto_fallback *fallback = &blk_crypto_fallback;
struct bio *src_bio, *enc_bio;
struct bio_crypt_ctx *bc;
struct blk_ksm_keyslot *slot;
@@ -295,7 +310,7 @@ static bool blk_crypto_fallback_encrypt_bio(struct bio **bio_ptr)
* Use the crypto API fallback keyslot manager to get a crypto_skcipher
* for the algorithm and key specified for this bio.
*/
- blk_st = blk_ksm_get_slot_for_key(&blk_crypto_ksm, bc->bc_key, &slot);
+ blk_st = blk_ksm_get_slot_for_key(&fallback->ksm, bc->bc_key, &slot);
if (blk_st != BLK_STS_OK) {
src_bio->bi_status = blk_st;
goto out_put_enc_bio;
@@ -319,7 +334,7 @@ static bool blk_crypto_fallback_encrypt_bio(struct bio **bio_ptr)
struct bio_vec *enc_bvec = &enc_bio->bi_io_vec[i];
struct page *plaintext_page = enc_bvec->bv_page;
struct page *ciphertext_page =
- mempool_alloc(blk_crypto_bounce_page_pool, GFP_NOIO);
+ mempool_alloc(fallback->bounce_page_pool, GFP_NOIO);
enc_bvec->bv_page = ciphertext_page;
@@ -359,7 +374,7 @@ static bool blk_crypto_fallback_encrypt_bio(struct bio **bio_ptr)
out_free_bounce_pages:
while (i > 0)
mempool_free(enc_bio->bi_io_vec[--i].bv_page,
- blk_crypto_bounce_page_pool);
+ fallback->bounce_page_pool);
out_free_ciph_req:
skcipher_request_free(ciph_req);
out_release_keyslot:
@@ -377,6 +392,7 @@ static bool blk_crypto_fallback_encrypt_bio(struct bio **bio_ptr)
*/
static void blk_crypto_fallback_decrypt_bio(struct work_struct *work)
{
+ struct blk_crypto_fallback *fallback = &blk_crypto_fallback;
struct bio_fallback_crypt_ctx *f_ctx =
container_of(work, struct bio_fallback_crypt_ctx, work);
struct bio *bio = f_ctx->bio;
@@ -397,7 +413,7 @@ static void blk_crypto_fallback_decrypt_bio(struct work_struct *work)
* Use the crypto API fallback keyslot manager to get a crypto_skcipher
* for the algorithm and key specified for this bio.
*/
- blk_st = blk_ksm_get_slot_for_key(&blk_crypto_ksm, bc->bc_key, &slot);
+ blk_st = blk_ksm_get_slot_for_key(&fallback->ksm, bc->bc_key, &slot);
if (blk_st != BLK_STS_OK) {
bio->bi_status = blk_st;
goto out_no_keyslot;
@@ -437,7 +453,7 @@ static void blk_crypto_fallback_decrypt_bio(struct work_struct *work)
skcipher_request_free(ciph_req);
blk_ksm_put_slot(slot);
out_no_keyslot:
- mempool_free(f_ctx, bio_fallback_crypt_ctx_pool);
+ mempool_free(f_ctx, fallback->crypt_ctx_pool);
bio_endio(bio);
}
@@ -458,14 +474,14 @@ static void blk_crypto_fallback_decrypt_endio(struct bio *bio)
/* If there was an IO error, don't queue for decrypt. */
if (bio->bi_status) {
- mempool_free(f_ctx, bio_fallback_crypt_ctx_pool);
+ mempool_free(f_ctx, blk_crypto_fallback.crypt_ctx_pool);
bio_endio(bio);
return;
}
INIT_WORK(&f_ctx->work, blk_crypto_fallback_decrypt_bio);
f_ctx->bio = bio;
- queue_work(blk_crypto_wq, &f_ctx->work);
+ queue_work(blk_crypto_fallback.decrypt_wq, &f_ctx->work);
}
/**
@@ -490,17 +506,19 @@ static void blk_crypto_fallback_decrypt_endio(struct bio *bio)
*/
bool blk_crypto_fallback_bio_prep(struct bio **bio_ptr)
{
+ struct blk_crypto_fallback *fallback = &blk_crypto_fallback;
struct bio *bio = *bio_ptr;
struct bio_crypt_ctx *bc = bio->bi_crypt_context;
struct bio_fallback_crypt_ctx *f_ctx;
- if (WARN_ON_ONCE(!tfms_inited[bc->bc_key->crypto_cfg.crypto_mode])) {
+ if (WARN_ON_ONCE(!fallback->tfms_inited[
+ bc->bc_key->crypto_cfg.crypto_mode])) {
/* User didn't call blk_crypto_start_using_key() first */
bio->bi_status = BLK_STS_IOERR;
return false;
}
- if (!blk_ksm_crypto_cfg_supported(&blk_crypto_ksm,
+ if (!blk_ksm_crypto_cfg_supported(&fallback->ksm,
&bc->bc_key->crypto_cfg)) {
bio->bi_status = BLK_STS_NOTSUPP;
return false;
@@ -513,7 +531,7 @@ bool blk_crypto_fallback_bio_prep(struct bio **bio_ptr)
* bio READ case: Set up a f_ctx in the bio's bi_private and set the
* bi_end_io appropriately to trigger decryption when the bio is ended.
*/
- f_ctx = mempool_alloc(bio_fallback_crypt_ctx_pool, GFP_NOIO);
+ f_ctx = mempool_alloc(fallback->crypt_ctx_pool, GFP_NOIO);
f_ctx->crypt_ctx = *bc;
f_ctx->crypt_iter = bio->bi_iter;
f_ctx->bi_private_orig = bio->bi_private;
@@ -527,79 +545,82 @@ bool blk_crypto_fallback_bio_prep(struct bio **bio_ptr)
int blk_crypto_fallback_evict_key(const struct blk_crypto_key *key)
{
- return blk_ksm_evict_key(&blk_crypto_ksm, key);
+ return blk_ksm_evict_key(&blk_crypto_fallback.ksm, key);
}
-static bool blk_crypto_fallback_inited;
static int blk_crypto_fallback_init(void)
{
+ struct blk_crypto_fallback *fallback = &blk_crypto_fallback;
int i;
int err;
- if (blk_crypto_fallback_inited)
+ if (fallback->initialized)
return 0;
- prandom_bytes(blank_key, BLK_CRYPTO_MAX_KEY_SIZE);
+ prandom_bytes(fallback->blank_key, BLK_CRYPTO_MAX_KEY_SIZE);
- err = bioset_init(&crypto_bio_split, 64, 0, 0);
+ err = bioset_init(&fallback->bio_split, 64, 0, 0);
if (err)
goto out;
- err = blk_ksm_init(&blk_crypto_ksm, blk_crypto_num_keyslots);
+ err = blk_ksm_init(&fallback->ksm, fallback->num_keyslots);
if (err)
goto fail_free_bioset;
err = -ENOMEM;
- blk_crypto_ksm.ksm_ll_ops = blk_crypto_ksm_ll_ops;
- blk_crypto_ksm.max_dun_bytes_supported = BLK_CRYPTO_MAX_IV_SIZE;
+ fallback->ksm.ksm_ll_ops.keyslot_program =
+ blk_crypto_fallback_keyslot_program;
+ fallback->ksm.ksm_ll_ops.keyslot_evict =
+ blk_crypto_fallback_keyslot_evict;
+ fallback->ksm.max_dun_bytes_supported = BLK_CRYPTO_MAX_IV_SIZE;
/* All blk-crypto modes have a crypto API fallback. */
for (i = 0; i < BLK_ENCRYPTION_MODE_MAX; i++)
- blk_crypto_ksm.crypto_modes_supported[i] = 0xFFFFFFFF;
- blk_crypto_ksm.crypto_modes_supported[BLK_ENCRYPTION_MODE_INVALID] = 0;
-
- blk_crypto_wq = alloc_workqueue("blk_crypto_wq",
- WQ_UNBOUND | WQ_HIGHPRI |
- WQ_MEM_RECLAIM, num_online_cpus());
- if (!blk_crypto_wq)
+ fallback->ksm.crypto_modes_supported[i] = 0xFFFFFFFF;
+ fallback->ksm.crypto_modes_supported[BLK_ENCRYPTION_MODE_INVALID] = 0;
+
+ fallback->decrypt_wq = alloc_workqueue("blk_crypto_fallback_wq",
+ WQ_UNBOUND | WQ_HIGHPRI |
+ WQ_MEM_RECLAIM,
+ num_online_cpus());
+ if (!fallback->decrypt_wq)
goto fail_free_ksm;
- blk_crypto_keyslots = kcalloc(blk_crypto_num_keyslots,
- sizeof(blk_crypto_keyslots[0]),
- GFP_KERNEL);
- if (!blk_crypto_keyslots)
+ fallback->keyslots = kcalloc(fallback->num_keyslots,
+ sizeof(fallback->keyslots[0]), GFP_KERNEL);
+ if (!fallback->keyslots)
goto fail_free_wq;
- blk_crypto_bounce_page_pool =
- mempool_create_page_pool(num_prealloc_bounce_pg, 0);
- if (!blk_crypto_bounce_page_pool)
+ fallback->bounce_page_pool =
+ mempool_create_page_pool(fallback->num_prealloc_bounce_pg, 0);
+ if (!fallback->bounce_page_pool)
goto fail_free_keyslots;
- bio_fallback_crypt_ctx_cache = KMEM_CACHE(bio_fallback_crypt_ctx, 0);
- if (!bio_fallback_crypt_ctx_cache)
+ fallback->crypt_ctx_cache = KMEM_CACHE(bio_fallback_crypt_ctx, 0);
+ if (!fallback->crypt_ctx_cache)
goto fail_free_bounce_page_pool;
- bio_fallback_crypt_ctx_pool =
- mempool_create_slab_pool(num_prealloc_fallback_crypt_ctxs,
- bio_fallback_crypt_ctx_cache);
- if (!bio_fallback_crypt_ctx_pool)
+ fallback->crypt_ctx_pool =
+ mempool_create_slab_pool(fallback->num_prealloc_crypt_ctxs,
+ fallback->crypt_ctx_cache);
+ if (!fallback->crypt_ctx_pool)
goto fail_free_crypt_ctx_cache;
- blk_crypto_fallback_inited = true;
+ fallback->initialized = true;
return 0;
fail_free_crypt_ctx_cache:
- kmem_cache_destroy(bio_fallback_crypt_ctx_cache);
+ kmem_cache_destroy(fallback->crypt_ctx_cache);
fail_free_bounce_page_pool:
- mempool_destroy(blk_crypto_bounce_page_pool);
+ mempool_destroy(fallback->bounce_page_pool);
fail_free_keyslots:
- kfree(blk_crypto_keyslots);
+ kfree(fallback->keyslots);
fail_free_wq:
- destroy_workqueue(blk_crypto_wq);
+ destroy_workqueue(fallback->decrypt_wq);
fail_free_ksm:
- blk_ksm_destroy(&blk_crypto_ksm);
+ blk_ksm_destroy(&fallback->ksm);
fail_free_bioset:
- bioset_exit(&crypto_bio_split);
+ bioset_exit(&fallback->bio_split);
out:
return err;
}
@@ -610,29 +631,29 @@ static int blk_crypto_fallback_init(void)
*/
int blk_crypto_fallback_start_using_mode(enum blk_crypto_mode_num mode_num)
{
+ struct blk_crypto_fallback *fallback = &blk_crypto_fallback;
const char *cipher_str = blk_crypto_modes[mode_num].cipher_str;
struct blk_crypto_fallback_keyslot *slotp;
unsigned int i;
int err = 0;
/*
- * Fast path
- * Ensure that updates to blk_crypto_keyslots[i].tfms[mode_num]
- * for each i are visible before we try to access them.
+ * Fast path. Ensure that updates to keyslots[i].tfms[mode_num] for
+ * each i are visible before we try to access them.
*/
- if (likely(smp_load_acquire(&tfms_inited[mode_num])))
+ if (likely(smp_load_acquire(&fallback->tfms_inited[mode_num])))
return 0;
- mutex_lock(&tfms_init_lock);
- if (tfms_inited[mode_num])
+ mutex_lock(&fallback->tfms_init_lock);
+ if (fallback->tfms_inited[mode_num])
goto out;
err = blk_crypto_fallback_init();
if (err)
goto out;
- for (i = 0; i < blk_crypto_num_keyslots; i++) {
- slotp = &blk_crypto_keyslots[i];
+ for (i = 0; i < fallback->num_keyslots; i++) {
+ slotp = &fallback->keyslots[i];
slotp->tfms[mode_num] = crypto_alloc_skcipher(cipher_str, 0, 0);
if (IS_ERR(slotp->tfms[mode_num])) {
err = PTR_ERR(slotp->tfms[mode_num]);
@@ -650,19 +671,19 @@ int blk_crypto_fallback_start_using_mode(enum blk_crypto_mode_num mode_num)
}
/*
- * Ensure that updates to blk_crypto_keyslots[i].tfms[mode_num]
- * for each i are visible before we set tfms_inited[mode_num].
+ * Ensure that updates to keyslots[i].tfms[mode_num] for each i are
+ * visible before we set tfms_inited[mode_num].
*/
- smp_store_release(&tfms_inited[mode_num], true);
+ smp_store_release(&fallback->tfms_inited[mode_num], true);
goto out;
out_free_tfms:
- for (i = 0; i < blk_crypto_num_keyslots; i++) {
- slotp = &blk_crypto_keyslots[i];
+ for (i = 0; i < fallback->num_keyslots; i++) {
+ slotp = &fallback->keyslots[i];
crypto_free_skcipher(slotp->tfms[mode_num]);
slotp->tfms[mode_num] = NULL;
}
out:
- mutex_unlock(&tfms_init_lock);
+ mutex_unlock(&fallback->tfms_init_lock);
return err;
}
--
2.33.0
^ permalink raw reply related [flat|nested] 17+ messages in thread* [PATCH 4/5] blk-crypto: rename blk_keyslot_manager to blk_crypto_profile
2021-09-13 1:31 [PATCH 0/5] blk-crypto cleanups Eric Biggers
` (2 preceding siblings ...)
2021-09-13 1:31 ` [PATCH 3/5] blk-crypto: rename keyslot-manager files to blk-crypto-profile Eric Biggers
@ 2021-09-13 1:31 ` Eric Biggers
2021-09-14 9:04 ` Ulf Hansson
2021-09-14 21:52 ` Eric Biggers
2021-09-13 1:31 ` [PATCH 5/5] blk-crypto: update inline encryption documentation Eric Biggers
4 siblings, 2 replies; 17+ messages in thread
From: Eric Biggers @ 2021-09-13 1:31 UTC (permalink / raw)
To: linux-block; +Cc: linux-mmc, linux-scsi, dm-devel, Satya Tangirala
From: Eric Biggers <ebiggers@google.com>
blk_keyslot_manager is misnamed because it doesn't necessarily manage
keyslots. It actually does several different things:
- Contains the crypto capabilities of the device.
- Provides functions to control the inline encryption hardware.
Originally these were just for programming/evicting keyslots;
however, new functionality (hardware-wrapped keys) will require new
functions here which are unrelated to keyslots. Moreover,
device-mapper devices already (ab)use "keyslot_evict" to pass key
eviction requests to their underlying devices even though
device-mapper devices don't have any keyslots themselves (so it
really should be "evict_key", not "keyslot_evict").
- Sometimes (but not always!) it manages keyslots. Originally it
always did, but device-mapper devices don't have keyslots
themselves, so they use a "passthrough keyslot manager" which
doesn't actually manage keyslots. This hack works, but the
terminology is unnatural. Also, some hardware doesn't have keyslots
and thus also uses a "passthrough keyslot manager" (support for such
hardware is yet to be upstreamed, but it will happen eventually).
Let's stop having keyslot managers which don't actually manage keyslots.
Instead, rename blk_keyslot_manager to blk_crypto_profile.
This is a fairly big change, since for consistency it also has to update
keyslot manager-related function names, variable names, and comments --
not just the actual struct name. However it's still a fairly
straightforward change, as it doesn't change any actual functionality.
Signed-off-by: Eric Biggers <ebiggers@google.com>
---
block/blk-crypto-fallback.c | 60 ++--
block/blk-crypto-profile.c | 518 ++++++++++++++---------------
block/blk-crypto.c | 25 +-
block/blk-integrity.c | 2 +-
drivers/md/dm-core.h | 2 +-
drivers/md/dm-table.c | 168 +++++-----
drivers/md/dm.c | 8 +-
drivers/mmc/core/crypto.c | 11 +-
drivers/mmc/host/cqhci-crypto.c | 31 +-
drivers/scsi/ufs/ufshcd-crypto.c | 32 +-
drivers/scsi/ufs/ufshcd-crypto.h | 9 +-
drivers/scsi/ufs/ufshcd.c | 2 +-
drivers/scsi/ufs/ufshcd.h | 4 +-
include/linux/blk-crypto-profile.h | 164 +++++----
include/linux/blkdev.h | 18 +-
include/linux/device-mapper.h | 4 +-
include/linux/mmc/host.h | 2 +-
17 files changed, 548 insertions(+), 512 deletions(-)
diff --git a/block/blk-crypto-fallback.c b/block/blk-crypto-fallback.c
index 9ffbd169e2601..95f6caa058842 100644
--- a/block/blk-crypto-fallback.c
+++ b/block/blk-crypto-fallback.c
@@ -64,7 +64,7 @@ static struct blk_crypto_fallback {
struct bio_set bio_split;
- struct blk_keyslot_manager ksm;
+ struct blk_crypto_profile profile;
struct workqueue_struct *decrypt_wq;
@@ -126,9 +126,10 @@ static void blk_crypto_fallback_evict_keyslot(unsigned int slot)
slotp->crypto_mode = BLK_ENCRYPTION_MODE_INVALID;
}
-static int blk_crypto_fallback_keyslot_program(struct blk_keyslot_manager *ksm,
- const struct blk_crypto_key *key,
- unsigned int slot)
+static int
+blk_crypto_fallback_keyslot_program(struct blk_crypto_profile *profile,
+ const struct blk_crypto_key *key,
+ unsigned int slot)
{
struct blk_crypto_fallback *fallback = &blk_crypto_fallback;
struct blk_crypto_fallback_keyslot *slotp = &fallback->keyslots[slot];
@@ -150,7 +151,7 @@ static int blk_crypto_fallback_keyslot_program(struct blk_keyslot_manager *ksm,
return 0;
}
-static int blk_crypto_fallback_keyslot_evict(struct blk_keyslot_manager *ksm,
+static int blk_crypto_fallback_keyslot_evict(struct blk_crypto_profile *profile,
const struct blk_crypto_key *key,
unsigned int slot)
{
@@ -201,13 +202,13 @@ static struct bio *blk_crypto_fallback_clone_bio(struct bio *bio_src)
}
static bool
-blk_crypto_fallback_alloc_cipher_req(struct blk_ksm_keyslot *slot,
+blk_crypto_fallback_alloc_cipher_req(struct blk_crypto_keyslot *slot,
struct skcipher_request **ciph_req_ret,
struct crypto_wait *wait)
{
struct skcipher_request *ciph_req;
const struct blk_crypto_fallback_keyslot *slotp;
- int keyslot_idx = blk_ksm_get_slot_idx(slot);
+ int keyslot_idx = blk_crypto_keyslot_index(slot);
slotp = &blk_crypto_fallback.keyslots[keyslot_idx];
ciph_req = skcipher_request_alloc(slotp->tfms[slotp->crypto_mode],
@@ -280,7 +281,7 @@ static bool blk_crypto_fallback_encrypt_bio(struct bio **bio_ptr)
struct blk_crypto_fallback *fallback = &blk_crypto_fallback;
struct bio *src_bio, *enc_bio;
struct bio_crypt_ctx *bc;
- struct blk_ksm_keyslot *slot;
+ struct blk_crypto_keyslot *slot;
int data_unit_size;
struct skcipher_request *ciph_req = NULL;
DECLARE_CRYPTO_WAIT(wait);
@@ -307,10 +308,10 @@ static bool blk_crypto_fallback_encrypt_bio(struct bio **bio_ptr)
}
/*
- * Use the crypto API fallback keyslot manager to get a crypto_skcipher
- * for the algorithm and key specified for this bio.
+ * Get a blk-crypto-fallback keyslot that contains a crypto_skcipher for
+ * this bio's algorithm and key.
*/
- blk_st = blk_ksm_get_slot_for_key(&fallback->ksm, bc->bc_key, &slot);
+ blk_st = blk_crypto_get_keyslot(&fallback->profile, bc->bc_key, &slot);
if (blk_st != BLK_STS_OK) {
src_bio->bi_status = blk_st;
goto out_put_enc_bio;
@@ -378,7 +379,7 @@ static bool blk_crypto_fallback_encrypt_bio(struct bio **bio_ptr)
out_free_ciph_req:
skcipher_request_free(ciph_req);
out_release_keyslot:
- blk_ksm_put_slot(slot);
+ blk_crypto_put_keyslot(slot);
out_put_enc_bio:
if (enc_bio)
bio_put(enc_bio);
@@ -397,7 +398,7 @@ static void blk_crypto_fallback_decrypt_bio(struct work_struct *work)
container_of(work, struct bio_fallback_crypt_ctx, work);
struct bio *bio = f_ctx->bio;
struct bio_crypt_ctx *bc = &f_ctx->crypt_ctx;
- struct blk_ksm_keyslot *slot;
+ struct blk_crypto_keyslot *slot;
struct skcipher_request *ciph_req = NULL;
DECLARE_CRYPTO_WAIT(wait);
u64 curr_dun[BLK_CRYPTO_DUN_ARRAY_SIZE];
@@ -410,10 +411,10 @@ static void blk_crypto_fallback_decrypt_bio(struct work_struct *work)
blk_status_t blk_st;
/*
- * Use the crypto API fallback keyslot manager to get a crypto_skcipher
- * for the algorithm and key specified for this bio.
+ * Get a blk-crypto-fallback keyslot that contains a crypto_skcipher for
+ * this bio's algorithm and key.
*/
- blk_st = blk_ksm_get_slot_for_key(&fallback->ksm, bc->bc_key, &slot);
+ blk_st = blk_crypto_get_keyslot(&fallback->profile, bc->bc_key, &slot);
if (blk_st != BLK_STS_OK) {
bio->bi_status = blk_st;
goto out_no_keyslot;
@@ -451,7 +452,7 @@ static void blk_crypto_fallback_decrypt_bio(struct work_struct *work)
out:
skcipher_request_free(ciph_req);
- blk_ksm_put_slot(slot);
+ blk_crypto_put_keyslot(slot);
out_no_keyslot:
mempool_free(f_ctx, fallback->crypt_ctx_pool);
bio_endio(bio);
@@ -518,8 +519,8 @@ bool blk_crypto_fallback_bio_prep(struct bio **bio_ptr)
return false;
}
- if (!blk_ksm_crypto_cfg_supported(&fallback->ksm,
- &bc->bc_key->crypto_cfg)) {
+ if (!__blk_crypto_cfg_supported(&fallback->profile,
+ &bc->bc_key->crypto_cfg)) {
bio->bi_status = BLK_STS_NOTSUPP;
return false;
}
@@ -545,7 +546,7 @@ bool blk_crypto_fallback_bio_prep(struct bio **bio_ptr)
int blk_crypto_fallback_evict_key(const struct blk_crypto_key *key)
{
- return blk_ksm_evict_key(&blk_crypto_fallback.ksm, key);
+ return __blk_crypto_evict_key(&blk_crypto_fallback.profile, key);
}
static int blk_crypto_fallback_init(void)
@@ -563,28 +564,29 @@ static int blk_crypto_fallback_init(void)
if (err)
goto out;
- err = blk_ksm_init(&fallback->ksm, fallback->num_keyslots);
+ err = blk_crypto_profile_init(&fallback->profile,
+ fallback->num_keyslots);
if (err)
goto fail_free_bioset;
err = -ENOMEM;
- fallback->ksm.ksm_ll_ops.keyslot_program =
+ fallback->profile.ll_ops.keyslot_program =
blk_crypto_fallback_keyslot_program;
- fallback->ksm.ksm_ll_ops.keyslot_evict =
+ fallback->profile.ll_ops.keyslot_evict =
blk_crypto_fallback_keyslot_evict;
- fallback->ksm.max_dun_bytes_supported = BLK_CRYPTO_MAX_IV_SIZE;
+ fallback->profile.max_dun_bytes_supported = BLK_CRYPTO_MAX_IV_SIZE;
/* All blk-crypto modes have a crypto API fallback. */
for (i = 0; i < BLK_ENCRYPTION_MODE_MAX; i++)
- fallback->ksm.crypto_modes_supported[i] = 0xFFFFFFFF;
- fallback->ksm.crypto_modes_supported[BLK_ENCRYPTION_MODE_INVALID] = 0;
+ fallback->profile.modes_supported[i] = 0xFFFFFFFF;
+ fallback->profile.modes_supported[BLK_ENCRYPTION_MODE_INVALID] = 0;
fallback->decrypt_wq = alloc_workqueue("blk_crypto_fallback_wq",
WQ_UNBOUND | WQ_HIGHPRI |
WQ_MEM_RECLAIM,
num_online_cpus());
if (!fallback->decrypt_wq)
- goto fail_free_ksm;
+ goto fail_destroy_profile;
fallback->keyslots = kcalloc(fallback->num_keyslots,
sizeof(fallback->keyslots[0]), GFP_KERNEL);
@@ -617,8 +619,8 @@ static int blk_crypto_fallback_init(void)
kfree(fallback->keyslots);
fail_free_wq:
destroy_workqueue(fallback->decrypt_wq);
-fail_free_ksm:
- blk_ksm_destroy(&fallback->ksm);
+fail_destroy_profile:
+ blk_crypto_profile_destroy(&fallback->profile);
fail_free_bioset:
bioset_exit(&fallback->bio_split);
out:
diff --git a/block/blk-crypto-profile.c b/block/blk-crypto-profile.c
index a58daf93c9ba6..bd05f3f555d89 100644
--- a/block/blk-crypto-profile.c
+++ b/block/blk-crypto-profile.c
@@ -4,26 +4,22 @@
*/
/**
- * DOC: The Keyslot Manager
+ * DOC: blk-crypto profiles
*
- * Many devices with inline encryption support have a limited number of "slots"
- * into which encryption contexts may be programmed, and requests can be tagged
- * with a slot number to specify the key to use for en/decryption.
+ * 'struct blk_crypto_profile' contains all generic inline encryption-related
+ * state for a particular inline encryption device. blk_crypto_profile serves
+ * as the way that drivers for inline encryption hardware expose their crypto
+ * capabilities and certain functions (e.g., functions to program and evict
+ * keys) to upper layers. Device drivers that want to support inline encryption
+ * construct a crypto profile, then associate it with the disk's request_queue.
*
- * As the number of slots is limited, and programming keys is expensive on
- * many inline encryption hardware, we don't want to program the same key into
- * multiple slots - if multiple requests are using the same key, we want to
- * program just one slot with that key and use that slot for all requests.
+ * If the device has keyslots, then its blk_crypto_profile also handles managing
+ * these keyslots in a device-independent way (using the driver-provided
+ * functions to program and evict keys as needed). This includes keeping track
+ * of which key and how many I/O requests are using each keyslot, getting
+ * keyslots for I/O requests, and handling key eviction requests.
*
- * The keyslot manager manages these keyslots appropriately, and also acts as
- * an abstraction between the inline encryption hardware and the upper layers.
- *
- * Lower layer devices will set up a keyslot manager in their request queue
- * and tell it how to perform device specific operations like programming/
- * evicting keys from keyslots.
- *
- * Upper layers will call blk_ksm_get_slot_for_key() to program a
- * key into some slot in the inline encryption hardware.
+ * For more information, see Documentation/block/inline-encryption.rst.
*/
#define pr_fmt(fmt) "blk-crypto: " fmt
@@ -36,77 +32,75 @@
#include <linux/wait.h>
#include <linux/blkdev.h>
-struct blk_ksm_keyslot {
+struct blk_crypto_keyslot {
atomic_t slot_refs;
struct list_head idle_slot_node;
struct hlist_node hash_node;
const struct blk_crypto_key *key;
- struct blk_keyslot_manager *ksm;
+ struct blk_crypto_profile *profile;
};
-static inline void blk_ksm_hw_enter(struct blk_keyslot_manager *ksm)
+static inline void blk_crypto_hw_enter(struct blk_crypto_profile *profile)
{
/*
- * Calling into the driver requires ksm->lock held and the device
+ * Calling into the driver requires profile->lock held and the device
* resumed. But we must resume the device first, since that can acquire
- * and release ksm->lock via blk_ksm_reprogram_all_keys().
+ * and release profile->lock via blk_crypto_reprogram_all_keys().
*/
- if (ksm->dev)
- pm_runtime_get_sync(ksm->dev);
- down_write(&ksm->lock);
+ if (profile->dev)
+ pm_runtime_get_sync(profile->dev);
+ down_write(&profile->lock);
}
-static inline void blk_ksm_hw_exit(struct blk_keyslot_manager *ksm)
+static inline void blk_crypto_hw_exit(struct blk_crypto_profile *profile)
{
- up_write(&ksm->lock);
- if (ksm->dev)
- pm_runtime_put_sync(ksm->dev);
-}
-
-static inline bool blk_ksm_is_passthrough(struct blk_keyslot_manager *ksm)
-{
- return ksm->num_slots == 0;
+ up_write(&profile->lock);
+ if (profile->dev)
+ pm_runtime_put_sync(profile->dev);
}
/**
- * blk_ksm_init() - Initialize a keyslot manager
- * @ksm: The keyslot_manager to initialize.
- * @num_slots: The number of key slots to manage.
+ * blk_crypto_profile_init() - Initialize a blk_crypto_profile
+ * @profile: the blk_crypto_profile to initialize
+ * @num_slots: the number of keyslots
*
- * Allocate memory for keyslots and initialize a keyslot manager. Called by
- * e.g. storage drivers to set up a keyslot manager in their request_queue.
+ * Storage drivers must call this when starting to set up a blk_crypto_profile,
+ * before filling in additional fields.
*
* Return: 0 on success, or else a negative error code.
*/
-int blk_ksm_init(struct blk_keyslot_manager *ksm, unsigned int num_slots)
+int blk_crypto_profile_init(struct blk_crypto_profile *profile,
+ unsigned int num_slots)
{
unsigned int slot;
unsigned int i;
unsigned int slot_hashtable_size;
- memset(ksm, 0, sizeof(*ksm));
+ memset(profile, 0, sizeof(*profile));
+ init_rwsem(&profile->lock);
if (num_slots == 0)
- return -EINVAL;
+ return 0;
- ksm->slots = kvcalloc(num_slots, sizeof(ksm->slots[0]), GFP_KERNEL);
- if (!ksm->slots)
- return -ENOMEM;
+ /* Initialize keyslot management data. */
- ksm->num_slots = num_slots;
+ profile->slots = kvcalloc(num_slots, sizeof(profile->slots[0]),
+ GFP_KERNEL);
+ if (!profile->slots)
+ return -ENOMEM;
- init_rwsem(&ksm->lock);
+ profile->num_slots = num_slots;
- init_waitqueue_head(&ksm->idle_slots_wait_queue);
- INIT_LIST_HEAD(&ksm->idle_slots);
+ init_waitqueue_head(&profile->idle_slots_wait_queue);
+ INIT_LIST_HEAD(&profile->idle_slots);
for (slot = 0; slot < num_slots; slot++) {
- ksm->slots[slot].ksm = ksm;
- list_add_tail(&ksm->slots[slot].idle_slot_node,
- &ksm->idle_slots);
+ profile->slots[slot].profile = profile;
+ list_add_tail(&profile->slots[slot].idle_slot_node,
+ &profile->idle_slots);
}
- spin_lock_init(&ksm->idle_slots_lock);
+ spin_lock_init(&profile->idle_slots_lock);
slot_hashtable_size = roundup_pow_of_two(num_slots);
/*
@@ -116,74 +110,80 @@ int blk_ksm_init(struct blk_keyslot_manager *ksm, unsigned int num_slots)
if (slot_hashtable_size < 2)
slot_hashtable_size = 2;
- ksm->log_slot_ht_size = ilog2(slot_hashtable_size);
- ksm->slot_hashtable = kvmalloc_array(slot_hashtable_size,
- sizeof(ksm->slot_hashtable[0]),
- GFP_KERNEL);
- if (!ksm->slot_hashtable)
- goto err_destroy_ksm;
+ profile->log_slot_ht_size = ilog2(slot_hashtable_size);
+ profile->slot_hashtable =
+ kvmalloc_array(slot_hashtable_size,
+ sizeof(profile->slot_hashtable[0]), GFP_KERNEL);
+ if (!profile->slot_hashtable)
+ goto err_destroy;
for (i = 0; i < slot_hashtable_size; i++)
- INIT_HLIST_HEAD(&ksm->slot_hashtable[i]);
+ INIT_HLIST_HEAD(&profile->slot_hashtable[i]);
return 0;
-err_destroy_ksm:
- blk_ksm_destroy(ksm);
+err_destroy:
+ blk_crypto_profile_destroy(profile);
return -ENOMEM;
}
-EXPORT_SYMBOL_GPL(blk_ksm_init);
+EXPORT_SYMBOL_GPL(blk_crypto_profile_init);
-static void blk_ksm_destroy_callback(void *ksm)
+static void blk_crypto_profile_destroy_callback(void *profile)
{
- blk_ksm_destroy(ksm);
+ blk_crypto_profile_destroy(profile);
}
/**
- * devm_blk_ksm_init() - Resource-managed blk_ksm_init()
- * @dev: The device which owns the blk_keyslot_manager.
- * @ksm: The blk_keyslot_manager to initialize.
- * @num_slots: The number of key slots to manage.
+ * devm_blk_crypto_profile_init() - Resource-managed blk_crypto_profile_init()
+ * @dev: the device which owns the blk_crypto_profile
+ * @profile: the blk_crypto_profile to initialize
+ * @num_slots: the number of keyslots
*
- * Like blk_ksm_init(), but causes blk_ksm_destroy() to be called automatically
- * on driver detach.
+ * Like blk_crypto_profile_init(), but causes blk_crypto_profile_destroy() to be
+ * called automatically on driver detach.
*
* Return: 0 on success, or else a negative error code.
*/
-int devm_blk_ksm_init(struct device *dev, struct blk_keyslot_manager *ksm,
- unsigned int num_slots)
+int devm_blk_crypto_profile_init(struct device *dev,
+ struct blk_crypto_profile *profile,
+ unsigned int num_slots)
{
- int err = blk_ksm_init(ksm, num_slots);
+ int err = blk_crypto_profile_init(profile, num_slots);
if (err)
return err;
- return devm_add_action_or_reset(dev, blk_ksm_destroy_callback, ksm);
+ return devm_add_action_or_reset(dev,
+ blk_crypto_profile_destroy_callback,
+ profile);
}
-EXPORT_SYMBOL_GPL(devm_blk_ksm_init);
+EXPORT_SYMBOL_GPL(devm_blk_crypto_profile_init);
static inline struct hlist_head *
-blk_ksm_hash_bucket_for_key(struct blk_keyslot_manager *ksm,
+blk_crypto_hash_bucket_for_key(struct blk_crypto_profile *profile,
const struct blk_crypto_key *key)
{
- return &ksm->slot_hashtable[hash_ptr(key, ksm->log_slot_ht_size)];
+ return &profile->slot_hashtable[
+ hash_ptr(key, profile->log_slot_ht_size)];
}
-static void blk_ksm_remove_slot_from_lru_list(struct blk_ksm_keyslot *slot)
+static void
+blk_crypto_remove_slot_from_lru_list(struct blk_crypto_keyslot *slot)
{
- struct blk_keyslot_manager *ksm = slot->ksm;
+ struct blk_crypto_profile *profile = slot->profile;
unsigned long flags;
- spin_lock_irqsave(&ksm->idle_slots_lock, flags);
+ spin_lock_irqsave(&profile->idle_slots_lock, flags);
list_del(&slot->idle_slot_node);
- spin_unlock_irqrestore(&ksm->idle_slots_lock, flags);
+ spin_unlock_irqrestore(&profile->idle_slots_lock, flags);
}
-static struct blk_ksm_keyslot *blk_ksm_find_keyslot(
- struct blk_keyslot_manager *ksm,
- const struct blk_crypto_key *key)
+static struct blk_crypto_keyslot *
+blk_crypto_find_keyslot(struct blk_crypto_profile *profile,
+ const struct blk_crypto_key *key)
{
- const struct hlist_head *head = blk_ksm_hash_bucket_for_key(ksm, key);
- struct blk_ksm_keyslot *slotp;
+ const struct hlist_head *head =
+ blk_crypto_hash_bucket_for_key(profile, key);
+ struct blk_crypto_keyslot *slotp;
hlist_for_each_entry(slotp, head, hash_node) {
if (slotp->key == key)
@@ -192,68 +192,79 @@ static struct blk_ksm_keyslot *blk_ksm_find_keyslot(
return NULL;
}
-static struct blk_ksm_keyslot *blk_ksm_find_and_grab_keyslot(
- struct blk_keyslot_manager *ksm,
- const struct blk_crypto_key *key)
+static struct blk_crypto_keyslot *
+blk_crypto_find_and_grab_keyslot(struct blk_crypto_profile *profile,
+ const struct blk_crypto_key *key)
{
- struct blk_ksm_keyslot *slot;
+ struct blk_crypto_keyslot *slot;
- slot = blk_ksm_find_keyslot(ksm, key);
+ slot = blk_crypto_find_keyslot(profile, key);
if (!slot)
return NULL;
if (atomic_inc_return(&slot->slot_refs) == 1) {
/* Took first reference to this slot; remove it from LRU list */
- blk_ksm_remove_slot_from_lru_list(slot);
+ blk_crypto_remove_slot_from_lru_list(slot);
}
return slot;
}
-unsigned int blk_ksm_get_slot_idx(struct blk_ksm_keyslot *slot)
+/**
+ * blk_crypto_keyslot_index() - Get the index of a keyslot
+ * @slot: a keyslot that blk_crypto_get_keyslot() returned
+ *
+ * Return: the 0-based index of the keyslot within the device's keyslots.
+ */
+unsigned int blk_crypto_keyslot_index(const struct blk_crypto_keyslot *slot)
{
- return slot - slot->ksm->slots;
+ return slot - slot->profile->slots;
}
-EXPORT_SYMBOL_GPL(blk_ksm_get_slot_idx);
+EXPORT_SYMBOL_GPL(blk_crypto_keyslot_index);
/**
- * blk_ksm_get_slot_for_key() - Program a key into a keyslot.
- * @ksm: The keyslot manager to program the key into.
- * @key: Pointer to the key object to program, including the raw key, crypto
- * mode, and data unit size.
- * @slot_ptr: A pointer to return the pointer of the allocated keyslot.
+ * blk_crypto_get_keyslot() - Get a keyslot for a key, if needed.
+ * @profile: the crypto profile of the device the key is being used on
+ * @key: the key that will be used
+ * @slot_ptr: If a keyslot is allocated, an opaque pointer to the keyslot struct
+ * will be stored here; otherwise NULL will be stored here.
+ *
+ * If the device has keyslots, get a keyslot that's been programmed with the
+ * specified key. If the key is already in a slot, we'll reuse it; otherwise
+ * we'll wait for a slot to become idle and program the key into it.
*
- * Get a keyslot that's been programmed with the specified key. If one already
- * exists, return it with incremented refcount. Otherwise, wait for a keyslot
- * to become idle and program it.
+ * This must be paired with a call to blk_crypto_put_keyslot().
*
- * Context: Process context. Takes and releases ksm->lock.
- * Return: BLK_STS_OK on success (and keyslot is set to the pointer of the
- * allocated keyslot), or some other blk_status_t otherwise (and
- * keyslot is set to NULL).
+ * Context: Process context. Takes and releases profile->lock.
+ * Return: BLK_STS_OK on success, meaning that either a keyslot was allocated or
+ * one wasn't needed; or a blk_status_t error on failure.
*/
-blk_status_t blk_ksm_get_slot_for_key(struct blk_keyslot_manager *ksm,
- const struct blk_crypto_key *key,
- struct blk_ksm_keyslot **slot_ptr)
+blk_status_t blk_crypto_get_keyslot(struct blk_crypto_profile *profile,
+ const struct blk_crypto_key *key,
+ struct blk_crypto_keyslot **slot_ptr)
{
- struct blk_ksm_keyslot *slot;
+ struct blk_crypto_keyslot *slot;
int slot_idx;
int err;
*slot_ptr = NULL;
- if (blk_ksm_is_passthrough(ksm))
+ /*
+ * If the device has no concept of "keyslots", then there is no need to
+ * get one.
+ */
+ if (profile->num_slots == 0)
return BLK_STS_OK;
- down_read(&ksm->lock);
- slot = blk_ksm_find_and_grab_keyslot(ksm, key);
- up_read(&ksm->lock);
+ down_read(&profile->lock);
+ slot = blk_crypto_find_and_grab_keyslot(profile, key);
+ up_read(&profile->lock);
if (slot)
goto success;
for (;;) {
- blk_ksm_hw_enter(ksm);
- slot = blk_ksm_find_and_grab_keyslot(ksm, key);
+ blk_crypto_hw_enter(profile);
+ slot = blk_crypto_find_and_grab_keyslot(profile, key);
if (slot) {
- blk_ksm_hw_exit(ksm);
+ blk_crypto_hw_exit(profile);
goto success;
}
@@ -261,22 +272,22 @@ blk_status_t blk_ksm_get_slot_for_key(struct blk_keyslot_manager *ksm,
* If we're here, that means there wasn't a slot that was
* already programmed with the key. So try to program it.
*/
- if (!list_empty(&ksm->idle_slots))
+ if (!list_empty(&profile->idle_slots))
break;
- blk_ksm_hw_exit(ksm);
- wait_event(ksm->idle_slots_wait_queue,
- !list_empty(&ksm->idle_slots));
+ blk_crypto_hw_exit(profile);
+ wait_event(profile->idle_slots_wait_queue,
+ !list_empty(&profile->idle_slots));
}
- slot = list_first_entry(&ksm->idle_slots, struct blk_ksm_keyslot,
+ slot = list_first_entry(&profile->idle_slots, struct blk_crypto_keyslot,
idle_slot_node);
- slot_idx = blk_ksm_get_slot_idx(slot);
+ slot_idx = blk_crypto_keyslot_index(slot);
- err = ksm->ksm_ll_ops.keyslot_program(ksm, key, slot_idx);
+ err = profile->ll_ops.keyslot_program(profile, key, slot_idx);
if (err) {
- wake_up(&ksm->idle_slots_wait_queue);
- blk_ksm_hw_exit(ksm);
+ wake_up(&profile->idle_slots_wait_queue);
+ blk_crypto_hw_exit(profile);
return errno_to_blk_status(err);
}
@@ -284,97 +295,98 @@ blk_status_t blk_ksm_get_slot_for_key(struct blk_keyslot_manager *ksm,
if (slot->key)
hlist_del(&slot->hash_node);
slot->key = key;
- hlist_add_head(&slot->hash_node, blk_ksm_hash_bucket_for_key(ksm, key));
+ hlist_add_head(&slot->hash_node,
+ blk_crypto_hash_bucket_for_key(profile, key));
atomic_set(&slot->slot_refs, 1);
- blk_ksm_remove_slot_from_lru_list(slot);
+ blk_crypto_remove_slot_from_lru_list(slot);
- blk_ksm_hw_exit(ksm);
+ blk_crypto_hw_exit(profile);
success:
*slot_ptr = slot;
return BLK_STS_OK;
}
/**
- * blk_ksm_put_slot() - Release a reference to a slot
- * @slot: The keyslot to release the reference of.
+ * blk_crypto_put_keyslot() - Release a reference to a keyslot
+ * @slot: The keyslot to release the reference of (may be NULL).
*
* Context: Any context.
*/
-void blk_ksm_put_slot(struct blk_ksm_keyslot *slot)
+void blk_crypto_put_keyslot(struct blk_crypto_keyslot *slot)
{
- struct blk_keyslot_manager *ksm;
+ struct blk_crypto_profile *profile;
unsigned long flags;
if (!slot)
return;
- ksm = slot->ksm;
+ profile = slot->profile;
if (atomic_dec_and_lock_irqsave(&slot->slot_refs,
- &ksm->idle_slots_lock, flags)) {
- list_add_tail(&slot->idle_slot_node, &ksm->idle_slots);
- spin_unlock_irqrestore(&ksm->idle_slots_lock, flags);
- wake_up(&ksm->idle_slots_wait_queue);
+ &profile->idle_slots_lock, flags)) {
+ list_add_tail(&slot->idle_slot_node, &profile->idle_slots);
+ spin_unlock_irqrestore(&profile->idle_slots_lock, flags);
+ wake_up(&profile->idle_slots_wait_queue);
}
}
/**
- * blk_ksm_crypto_cfg_supported() - Find out if a crypto configuration is
- * supported by a ksm.
- * @ksm: The keyslot manager to check
- * @cfg: The crypto configuration to check for.
- *
- * Checks for crypto_mode/data unit size/dun bytes support.
+ * __blk_crypto_cfg_supported() - Check whether the given crypto profile
+ * supports the given crypto configuration.
+ * @profile: the crypto profile to check
+ * @cfg: the crypto configuration to check for
*
- * Return: Whether or not this ksm supports the specified crypto config.
+ * Return: %true if @profile supports the given @cfg.
*/
-bool blk_ksm_crypto_cfg_supported(struct blk_keyslot_manager *ksm,
- const struct blk_crypto_config *cfg)
+bool __blk_crypto_cfg_supported(struct blk_crypto_profile *profile,
+ const struct blk_crypto_config *cfg)
{
- if (!ksm)
+ if (!profile)
return false;
- if (!(ksm->crypto_modes_supported[cfg->crypto_mode] &
- cfg->data_unit_size))
+ if (!(profile->modes_supported[cfg->crypto_mode] & cfg->data_unit_size))
return false;
- if (ksm->max_dun_bytes_supported < cfg->dun_bytes)
+ if (profile->max_dun_bytes_supported < cfg->dun_bytes)
return false;
return true;
}
/**
- * blk_ksm_evict_key() - Evict a key from the lower layer device.
- * @ksm: The keyslot manager to evict from
- * @key: The key to evict
+ * __blk_crypto_evict_key() - Evict a key from a device.
+ * @profile: the crypto profile of the device
+ * @key: the key to evict. It must not still be used in any I/O.
+ *
+ * If the device has keyslots, this finds the keyslot (if any) that contains the
+ * specified key and calls the driver's keyslot_evict function to evict it.
*
- * Find the keyslot that the specified key was programmed into, and evict that
- * slot from the lower layer device. The slot must not be in use by any
- * in-flight IO when this function is called.
+ * Otherwise, this just calls the driver's keyslot_evict function if it is
+ * implemented, passing just the key (without any particular keyslot). This
+ * allows layered devices to evict the key from their underlying devices.
*
- * Context: Process context. Takes and releases ksm->lock.
+ * Context: Process context. Takes and releases profile->lock.
* Return: 0 on success or if there's no keyslot with the specified key, -EBUSY
* if the keyslot is still in use, or another -errno value on other
* error.
*/
-int blk_ksm_evict_key(struct blk_keyslot_manager *ksm,
- const struct blk_crypto_key *key)
+int __blk_crypto_evict_key(struct blk_crypto_profile *profile,
+ const struct blk_crypto_key *key)
{
- struct blk_ksm_keyslot *slot;
+ struct blk_crypto_keyslot *slot;
int err = 0;
- if (blk_ksm_is_passthrough(ksm)) {
- if (ksm->ksm_ll_ops.keyslot_evict) {
- blk_ksm_hw_enter(ksm);
- err = ksm->ksm_ll_ops.keyslot_evict(ksm, key, -1);
- blk_ksm_hw_exit(ksm);
+ if (profile->num_slots == 0) {
+ if (profile->ll_ops.keyslot_evict) {
+ blk_crypto_hw_enter(profile);
+ err = profile->ll_ops.keyslot_evict(profile, key, -1);
+ blk_crypto_hw_exit(profile);
return err;
}
return 0;
}
- blk_ksm_hw_enter(ksm);
- slot = blk_ksm_find_keyslot(ksm, key);
+ blk_crypto_hw_enter(profile);
+ slot = blk_crypto_find_keyslot(profile, key);
if (!slot)
goto out_unlock;
@@ -382,8 +394,8 @@ int blk_ksm_evict_key(struct blk_keyslot_manager *ksm,
err = -EBUSY;
goto out_unlock;
}
- err = ksm->ksm_ll_ops.keyslot_evict(ksm, key,
- blk_ksm_get_slot_idx(slot));
+ err = profile->ll_ops.keyslot_evict(profile, key,
+ blk_crypto_keyslot_index(slot));
if (err)
goto out_unlock;
@@ -391,81 +403,84 @@ int blk_ksm_evict_key(struct blk_keyslot_manager *ksm,
slot->key = NULL;
err = 0;
out_unlock:
- blk_ksm_hw_exit(ksm);
+ blk_crypto_hw_exit(profile);
return err;
}
/**
- * blk_ksm_reprogram_all_keys() - Re-program all keyslots.
- * @ksm: The keyslot manager
+ * blk_crypto_reprogram_all_keys() - Re-program all keyslots.
+ * @profile: The crypto profile
*
* Re-program all keyslots that are supposed to have a key programmed. This is
* intended only for use by drivers for hardware that loses its keys on reset.
*
- * Context: Process context. Takes and releases ksm->lock.
+ * Context: Process context. Takes and releases profile->lock.
*/
-void blk_ksm_reprogram_all_keys(struct blk_keyslot_manager *ksm)
+void blk_crypto_reprogram_all_keys(struct blk_crypto_profile *profile)
{
unsigned int slot;
- if (blk_ksm_is_passthrough(ksm))
+ if (profile->num_slots == 0)
return;
/* This is for device initialization, so don't resume the device */
- down_write(&ksm->lock);
- for (slot = 0; slot < ksm->num_slots; slot++) {
- const struct blk_crypto_key *key = ksm->slots[slot].key;
+ down_write(&profile->lock);
+ for (slot = 0; slot < profile->num_slots; slot++) {
+ const struct blk_crypto_key *key = profile->slots[slot].key;
int err;
if (!key)
continue;
- err = ksm->ksm_ll_ops.keyslot_program(ksm, key, slot);
+ err = profile->ll_ops.keyslot_program(profile, key, slot);
WARN_ON(err);
}
- up_write(&ksm->lock);
+ up_write(&profile->lock);
}
-EXPORT_SYMBOL_GPL(blk_ksm_reprogram_all_keys);
+EXPORT_SYMBOL_GPL(blk_crypto_reprogram_all_keys);
-void blk_ksm_destroy(struct blk_keyslot_manager *ksm)
+void blk_crypto_profile_destroy(struct blk_crypto_profile *profile)
{
- if (!ksm)
+ if (!profile)
return;
- kvfree(ksm->slot_hashtable);
- kvfree_sensitive(ksm->slots, sizeof(ksm->slots[0]) * ksm->num_slots);
- memzero_explicit(ksm, sizeof(*ksm));
+ kvfree(profile->slot_hashtable);
+ kvfree_sensitive(profile->slots,
+ sizeof(profile->slots[0]) * profile->num_slots);
+ memzero_explicit(profile, sizeof(*profile));
}
-EXPORT_SYMBOL_GPL(blk_ksm_destroy);
+EXPORT_SYMBOL_GPL(blk_crypto_profile_destroy);
-bool blk_ksm_register(struct blk_keyslot_manager *ksm, struct request_queue *q)
+bool blk_crypto_register(struct blk_crypto_profile *profile,
+ struct request_queue *q)
{
if (blk_integrity_queue_supports_integrity(q)) {
pr_warn("Integrity and hardware inline encryption are not supported together. Disabling hardware inline encryption.\n");
return false;
}
- q->ksm = ksm;
+ q->crypto_profile = profile;
return true;
}
-EXPORT_SYMBOL_GPL(blk_ksm_register);
+EXPORT_SYMBOL_GPL(blk_crypto_register);
-void blk_ksm_unregister(struct request_queue *q)
+void blk_crypto_unregister(struct request_queue *q)
{
- q->ksm = NULL;
+ q->crypto_profile = NULL;
}
/**
- * blk_ksm_intersect_modes() - restrict supported modes by child device
- * @parent: The keyslot manager for parent device
- * @child: The keyslot manager for child device, or NULL
+ * blk_crypto_intersect_capabilities() - restrict supported crypto capabilities
+ * by child device
+ * @parent: the crypto profile for the parent device
+ * @child: the crypto profile for the child device, or NULL
*
- * Clear any crypto mode support bits in @parent that aren't set in @child.
- * If @child is NULL, then all parent bits are cleared.
+ * Clear all crypto capabilities in @parent that aren't set in @child. If
+ * @child is NULL, then all parent capabilities are cleared.
*
- * Only use this when setting up the keyslot manager for a layered device,
- * before it's been exposed yet.
+ * Only use this when setting up the crypto profile for a layered device, before
+ * it's been exposed yet.
*/
-void blk_ksm_intersect_modes(struct blk_keyslot_manager *parent,
- const struct blk_keyslot_manager *child)
+void blk_crypto_intersect_capabilities(struct blk_crypto_profile *parent,
+ const struct blk_crypto_profile *child)
{
if (child) {
unsigned int i;
@@ -473,73 +488,63 @@ void blk_ksm_intersect_modes(struct blk_keyslot_manager *parent,
parent->max_dun_bytes_supported =
min(parent->max_dun_bytes_supported,
child->max_dun_bytes_supported);
- for (i = 0; i < ARRAY_SIZE(child->crypto_modes_supported);
- i++) {
- parent->crypto_modes_supported[i] &=
- child->crypto_modes_supported[i];
- }
+ for (i = 0; i < ARRAY_SIZE(child->modes_supported); i++)
+ parent->modes_supported[i] &= child->modes_supported[i];
} else {
parent->max_dun_bytes_supported = 0;
- memset(parent->crypto_modes_supported, 0,
- sizeof(parent->crypto_modes_supported));
+ memset(parent->modes_supported, 0,
+ sizeof(parent->modes_supported));
}
}
-EXPORT_SYMBOL_GPL(blk_ksm_intersect_modes);
+EXPORT_SYMBOL_GPL(blk_crypto_intersect_capabilities);
/**
- * blk_ksm_is_superset() - Check if a KSM supports a superset of crypto modes
- * and DUN bytes that another KSM supports. Here,
- * "superset" refers to the mathematical meaning of the
- * word - i.e. if two KSMs have the *same* capabilities,
- * they *are* considered supersets of each other.
- * @ksm_superset: The KSM that we want to verify is a superset
- * @ksm_subset: The KSM that we want to verify is a subset
+ * blk_crypto_has_capabilities() - Check whether @target supports at least all
+ * the crypto capabilities that @reference does.
+ * @target: the target profile
+ * @reference: the reference profile
*
- * Return: True if @ksm_superset supports a superset of the crypto modes and DUN
- * bytes that @ksm_subset supports.
+ * Return: %true if @target supports all the crypto capabilities of @reference.
*/
-bool blk_ksm_is_superset(struct blk_keyslot_manager *ksm_superset,
- struct blk_keyslot_manager *ksm_subset)
+bool blk_crypto_has_capabilities(const struct blk_crypto_profile *target,
+ const struct blk_crypto_profile *reference)
{
int i;
- if (!ksm_subset)
+ if (!reference)
return true;
- if (!ksm_superset)
+ if (!target)
return false;
- for (i = 0; i < ARRAY_SIZE(ksm_superset->crypto_modes_supported); i++) {
- if (ksm_subset->crypto_modes_supported[i] &
- (~ksm_superset->crypto_modes_supported[i])) {
+ for (i = 0; i < ARRAY_SIZE(target->modes_supported); i++) {
+ if (reference->modes_supported[i] & ~target->modes_supported[i])
return false;
- }
}
- if (ksm_subset->max_dun_bytes_supported >
- ksm_superset->max_dun_bytes_supported) {
+ if (reference->max_dun_bytes_supported >
+ target->max_dun_bytes_supported)
return false;
- }
return true;
}
-EXPORT_SYMBOL_GPL(blk_ksm_is_superset);
+EXPORT_SYMBOL_GPL(blk_crypto_has_capabilities);
/**
- * blk_ksm_update_capabilities() - Update the restrictions of a KSM to those of
- * another KSM
- * @target_ksm: The KSM whose restrictions to update.
- * @reference_ksm: The KSM to whose restrictions this function will update
- * @target_ksm's restrictions to.
+ * blk_crypto_update_capabilities() - Update the capabilities of a crypto
+ * profile to match those of another crypto
+ * profile.
+ * @dst: The crypto profile whose capabilities to update.
+ * @src: The crypto profile whose capabilities this function will update @dst's
+ * capabilities to.
*
* Blk-crypto requires that crypto capabilities that were
* advertised when a bio was created continue to be supported by the
* device until that bio is ended. This is turn means that a device cannot
* shrink its advertised crypto capabilities without any explicit
* synchronization with upper layers. So if there's no such explicit
- * synchronization, @reference_ksm must support all the crypto capabilities that
- * @target_ksm does
- * (i.e. we need blk_ksm_is_superset(@reference_ksm, @target_ksm) == true).
+ * synchronization, @src must support all the crypto capabilities that
+ * @dst does (i.e. we need blk_crypto_has_capabilities(@src, @dst)).
*
* Note also that as long as the crypto capabilities are being expanded, the
* order of updates becoming visible is not important because it's alright
@@ -548,31 +553,12 @@ EXPORT_SYMBOL_GPL(blk_ksm_is_superset);
* might result in blk-crypto-fallback being used if available, or the bio being
* failed).
*/
-void blk_ksm_update_capabilities(struct blk_keyslot_manager *target_ksm,
- struct blk_keyslot_manager *reference_ksm)
+void blk_crypto_update_capabilities(struct blk_crypto_profile *dst,
+ const struct blk_crypto_profile *src)
{
- memcpy(target_ksm->crypto_modes_supported,
- reference_ksm->crypto_modes_supported,
- sizeof(target_ksm->crypto_modes_supported));
+ memcpy(dst->modes_supported, src->modes_supported,
+ sizeof(dst->modes_supported));
- target_ksm->max_dun_bytes_supported =
- reference_ksm->max_dun_bytes_supported;
-}
-EXPORT_SYMBOL_GPL(blk_ksm_update_capabilities);
-
-/**
- * blk_ksm_init_passthrough() - Init a passthrough keyslot manager
- * @ksm: The keyslot manager to init
- *
- * Initialize a passthrough keyslot manager.
- * Called by e.g. storage drivers to set up a keyslot manager in their
- * request_queue, when the storage driver wants to manage its keys by itself.
- * This is useful for inline encryption hardware that doesn't have the concept
- * of keyslots, and for layered devices.
- */
-void blk_ksm_init_passthrough(struct blk_keyslot_manager *ksm)
-{
- memset(ksm, 0, sizeof(*ksm));
- init_rwsem(&ksm->lock);
+ dst->max_dun_bytes_supported = src->max_dun_bytes_supported;
}
-EXPORT_SYMBOL_GPL(blk_ksm_init_passthrough);
+EXPORT_SYMBOL_GPL(blk_crypto_update_capabilities);
diff --git a/block/blk-crypto.c b/block/blk-crypto.c
index 9102803d36232..7ce02e251e15c 100644
--- a/block/blk-crypto.c
+++ b/block/blk-crypto.c
@@ -218,8 +218,9 @@ static bool bio_crypt_check_alignment(struct bio *bio)
blk_status_t __blk_crypto_init_request(struct request *rq)
{
- return blk_ksm_get_slot_for_key(rq->q->ksm, rq->crypt_ctx->bc_key,
- &rq->crypt_keyslot);
+ return blk_crypto_get_keyslot(rq->q->crypto_profile,
+ rq->crypt_ctx->bc_key,
+ &rq->crypt_keyslot);
}
/**
@@ -233,7 +234,7 @@ blk_status_t __blk_crypto_init_request(struct request *rq)
*/
void __blk_crypto_free_request(struct request *rq)
{
- blk_ksm_put_slot(rq->crypt_keyslot);
+ blk_crypto_put_keyslot(rq->crypt_keyslot);
mempool_free(rq->crypt_ctx, bio_crypt_ctx_pool);
blk_crypto_rq_set_defaults(rq);
}
@@ -264,6 +265,7 @@ bool __blk_crypto_bio_prep(struct bio **bio_ptr)
{
struct bio *bio = *bio_ptr;
const struct blk_crypto_key *bc_key = bio->bi_crypt_context->bc_key;
+ struct blk_crypto_profile *profile;
/* Error if bio has no data. */
if (WARN_ON_ONCE(!bio_has_data(bio))) {
@@ -280,8 +282,8 @@ bool __blk_crypto_bio_prep(struct bio **bio_ptr)
* Success if device supports the encryption context, or if we succeeded
* in falling back to the crypto API.
*/
- if (blk_ksm_crypto_cfg_supported(bio->bi_bdev->bd_disk->queue->ksm,
- &bc_key->crypto_cfg))
+ profile = bio->bi_bdev->bd_disk->queue->crypto_profile;
+ if (__blk_crypto_cfg_supported(profile, &bc_key->crypto_cfg))
return true;
if (blk_crypto_fallback_bio_prep(bio_ptr))
@@ -357,7 +359,7 @@ bool blk_crypto_config_supported(struct request_queue *q,
const struct blk_crypto_config *cfg)
{
return IS_ENABLED(CONFIG_BLK_INLINE_ENCRYPTION_FALLBACK) ||
- blk_ksm_crypto_cfg_supported(q->ksm, cfg);
+ __blk_crypto_cfg_supported(q->crypto_profile, cfg);
}
/**
@@ -378,7 +380,7 @@ bool blk_crypto_config_supported(struct request_queue *q,
int blk_crypto_start_using_key(const struct blk_crypto_key *key,
struct request_queue *q)
{
- if (blk_ksm_crypto_cfg_supported(q->ksm, &key->crypto_cfg))
+ if (__blk_crypto_cfg_supported(q->crypto_profile, &key->crypto_cfg))
return 0;
return blk_crypto_fallback_start_using_mode(key->crypto_cfg.crypto_mode);
}
@@ -399,13 +401,12 @@ int blk_crypto_start_using_key(const struct blk_crypto_key *key,
int blk_crypto_evict_key(struct request_queue *q,
const struct blk_crypto_key *key)
{
- if (blk_ksm_crypto_cfg_supported(q->ksm, &key->crypto_cfg))
- return blk_ksm_evict_key(q->ksm, key);
+ if (__blk_crypto_cfg_supported(q->crypto_profile, &key->crypto_cfg))
+ return __blk_crypto_evict_key(q->crypto_profile, key);
/*
- * If the request queue's associated inline encryption hardware didn't
- * have support for the key, then the key might have been programmed
- * into the fallback keyslot manager, so try to evict from there.
+ * If the request_queue didn't support the key, then blk-crypto-fallback
+ * may have been used, so try to evict the key from blk-crypto-fallback.
*/
return blk_crypto_fallback_evict_key(key);
}
diff --git a/block/blk-integrity.c b/block/blk-integrity.c
index 69a12177dfb62..db656d12050f7 100644
--- a/block/blk-integrity.c
+++ b/block/blk-integrity.c
@@ -411,7 +411,7 @@ void blk_integrity_register(struct gendisk *disk, struct blk_integrity *template
#ifdef CONFIG_BLK_INLINE_ENCRYPTION
if (disk->queue->ksm) {
pr_warn("blk-integrity: Integrity and hardware inline encryption are not supported together. Disabling hardware inline encryption.\n");
- blk_ksm_unregister(disk->queue);
+ blk_crypto_unregister(disk->queue);
}
#endif
}
diff --git a/drivers/md/dm-core.h b/drivers/md/dm-core.h
index 841ed87999e79..b855fef4f38a6 100644
--- a/drivers/md/dm-core.h
+++ b/drivers/md/dm-core.h
@@ -200,7 +200,7 @@ struct dm_table {
struct dm_md_mempools *mempools;
#ifdef CONFIG_BLK_INLINE_ENCRYPTION
- struct blk_keyslot_manager *ksm;
+ struct blk_crypto_profile *crypto_profile;
#endif
};
diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c
index 2111daaacabaf..63c414a1bd677 100644
--- a/drivers/md/dm-table.c
+++ b/drivers/md/dm-table.c
@@ -169,7 +169,7 @@ static void free_devices(struct list_head *devices, struct mapped_device *md)
}
}
-static void dm_table_destroy_keyslot_manager(struct dm_table *t);
+static void dm_table_destroy_crypto_profile(struct dm_table *t);
void dm_table_destroy(struct dm_table *t)
{
@@ -199,7 +199,7 @@ void dm_table_destroy(struct dm_table *t)
dm_free_md_mempools(t->mempools);
- dm_table_destroy_keyslot_manager(t);
+ dm_table_destroy_crypto_profile(t);
kfree(t);
}
@@ -1186,8 +1186,8 @@ static int dm_table_register_integrity(struct dm_table *t)
#ifdef CONFIG_BLK_INLINE_ENCRYPTION
-struct dm_keyslot_manager {
- struct blk_keyslot_manager ksm;
+struct dm_crypto_profile {
+ struct blk_crypto_profile profile;
struct mapped_device *md;
};
@@ -1213,13 +1213,11 @@ static int dm_keyslot_evict_callback(struct dm_target *ti, struct dm_dev *dev,
* When an inline encryption key is evicted from a device-mapper device, evict
* it from all the underlying devices.
*/
-static int dm_keyslot_evict(struct blk_keyslot_manager *ksm,
+static int dm_keyslot_evict(struct blk_crypto_profile *profile,
const struct blk_crypto_key *key, unsigned int slot)
{
- struct dm_keyslot_manager *dksm = container_of(ksm,
- struct dm_keyslot_manager,
- ksm);
- struct mapped_device *md = dksm->md;
+ struct mapped_device *md =
+ container_of(profile, struct dm_crypto_profile, profile)->md;
struct dm_keyslot_evict_args args = { key };
struct dm_table *t;
int srcu_idx;
@@ -1239,150 +1237,148 @@ static int dm_keyslot_evict(struct blk_keyslot_manager *ksm,
return args.err;
}
-static const struct blk_ksm_ll_ops dm_ksm_ll_ops = {
- .keyslot_evict = dm_keyslot_evict,
-};
-
-static int device_intersect_crypto_modes(struct dm_target *ti,
- struct dm_dev *dev, sector_t start,
- sector_t len, void *data)
+static int
+device_intersect_crypto_capabilities(struct dm_target *ti, struct dm_dev *dev,
+ sector_t start, sector_t len, void *data)
{
- struct blk_keyslot_manager *parent = data;
- struct blk_keyslot_manager *child = bdev_get_queue(dev->bdev)->ksm;
+ struct blk_crypto_profile *parent = data;
+ struct blk_crypto_profile *child =
+ bdev_get_queue(dev->bdev)->crypto_profile;
- blk_ksm_intersect_modes(parent, child);
+ blk_crypto_intersect_capabilities(parent, child);
return 0;
}
-void dm_destroy_keyslot_manager(struct blk_keyslot_manager *ksm)
+void dm_destroy_crypto_profile(struct blk_crypto_profile *profile)
{
- struct dm_keyslot_manager *dksm = container_of(ksm,
- struct dm_keyslot_manager,
- ksm);
+ struct dm_crypto_profile *dmcp = container_of(profile,
+ struct dm_crypto_profile,
+ profile);
- if (!ksm)
+ if (!profile)
return;
- blk_ksm_destroy(ksm);
- kfree(dksm);
+ blk_crypto_profile_destroy(profile);
+ kfree(dmcp);
}
-static void dm_table_destroy_keyslot_manager(struct dm_table *t)
+static void dm_table_destroy_crypto_profile(struct dm_table *t)
{
- dm_destroy_keyslot_manager(t->ksm);
- t->ksm = NULL;
+ dm_destroy_crypto_profile(t->crypto_profile);
+ t->crypto_profile = NULL;
}
/*
- * Constructs and initializes t->ksm with a keyslot manager that
- * represents the common set of crypto capabilities of the devices
- * described by the dm_table. However, if the constructed keyslot
- * manager does not support a superset of the crypto capabilities
- * supported by the current keyslot manager of the mapped_device,
- * it returns an error instead, since we don't support restricting
- * crypto capabilities on table changes. Finally, if the constructed
- * keyslot manager doesn't actually support any crypto modes at all,
- * it just returns NULL.
+ * Constructs and initializes t->crypto_profile with a crypto profile that
+ * represents the common set of crypto capabilities of the devices described by
+ * the dm_table. However, if the constructed crypto profile doesn't support all
+ * crypto capabilities that are supported by the current mapped_device, it
+ * returns an error instead, since we don't support removing crypto capabilities
+ * on table changes. Finally, if the constructed crypto profile is "empty" (has
+ * no crypto capabilities at all), it just sets t->crypto_profile to NULL.
*/
-static int dm_table_construct_keyslot_manager(struct dm_table *t)
+static int dm_table_construct_crypto_profile(struct dm_table *t)
{
- struct dm_keyslot_manager *dksm;
- struct blk_keyslot_manager *ksm;
+ struct dm_crypto_profile *dmcp;
+ struct blk_crypto_profile *profile;
struct dm_target *ti;
unsigned int i;
- bool ksm_is_empty = true;
+ bool empty_profile = true;
- dksm = kmalloc(sizeof(*dksm), GFP_KERNEL);
- if (!dksm)
+ dmcp = kmalloc(sizeof(*dmcp), GFP_KERNEL);
+ if (!dmcp)
return -ENOMEM;
- dksm->md = t->md;
+ dmcp->md = t->md;
- ksm = &dksm->ksm;
- blk_ksm_init_passthrough(ksm);
- ksm->ksm_ll_ops = dm_ksm_ll_ops;
- ksm->max_dun_bytes_supported = UINT_MAX;
- memset(ksm->crypto_modes_supported, 0xFF,
- sizeof(ksm->crypto_modes_supported));
+ profile = &dmcp->profile;
+ blk_crypto_profile_init(profile, 0);
+ profile->ll_ops.keyslot_evict = dm_keyslot_evict;
+ profile->max_dun_bytes_supported = UINT_MAX;
+ memset(profile->modes_supported, 0xFF,
+ sizeof(profile->modes_supported));
for (i = 0; i < dm_table_get_num_targets(t); i++) {
ti = dm_table_get_target(t, i);
if (!dm_target_passes_crypto(ti->type)) {
- blk_ksm_intersect_modes(ksm, NULL);
+ blk_crypto_intersect_capabilities(profile, NULL);
break;
}
if (!ti->type->iterate_devices)
continue;
- ti->type->iterate_devices(ti, device_intersect_crypto_modes,
- ksm);
+ ti->type->iterate_devices(ti,
+ device_intersect_crypto_capabilities,
+ profile);
}
- if (t->md->queue && !blk_ksm_is_superset(ksm, t->md->queue->ksm)) {
+ if (t->md->queue &&
+ !blk_crypto_has_capabilities(profile,
+ t->md->queue->crypto_profile)) {
DMWARN("Inline encryption capabilities of new DM table were more restrictive than the old table's. This is not supported!");
- dm_destroy_keyslot_manager(ksm);
+ dm_destroy_crypto_profile(profile);
return -EINVAL;
}
/*
- * If the new KSM doesn't actually support any crypto modes, we may as
- * well represent it with a NULL ksm.
+ * If the new profile doesn't actually support any crypto capabilities,
+ * we may as well represent it with a NULL profile.
*/
- ksm_is_empty = true;
- for (i = 0; i < ARRAY_SIZE(ksm->crypto_modes_supported); i++) {
- if (ksm->crypto_modes_supported[i]) {
- ksm_is_empty = false;
+ for (i = 0; i < ARRAY_SIZE(profile->modes_supported); i++) {
+ if (profile->modes_supported[i]) {
+ empty_profile = false;
break;
}
}
- if (ksm_is_empty) {
- dm_destroy_keyslot_manager(ksm);
- ksm = NULL;
+ if (empty_profile) {
+ dm_destroy_crypto_profile(profile);
+ profile = NULL;
}
/*
- * t->ksm is only set temporarily while the table is being set
- * up, and it gets set to NULL after the capabilities have
- * been transferred to the request_queue.
+ * t->crypto_profile is only set temporarily while the table is being
+ * set up, and it gets set to NULL after the profile has been
+ * transferred to the request_queue.
*/
- t->ksm = ksm;
+ t->crypto_profile = profile;
return 0;
}
-static void dm_update_keyslot_manager(struct request_queue *q,
- struct dm_table *t)
+static void dm_update_crypto_profile(struct request_queue *q,
+ struct dm_table *t)
{
- if (!t->ksm)
+ if (!t->crypto_profile)
return;
- /* Make the ksm less restrictive */
- if (!q->ksm) {
- blk_ksm_register(t->ksm, q);
+ /* Make the crypto profile less restrictive. */
+ if (!q->crypto_profile) {
+ blk_crypto_register(t->crypto_profile, q);
} else {
- blk_ksm_update_capabilities(q->ksm, t->ksm);
- dm_destroy_keyslot_manager(t->ksm);
+ blk_crypto_update_capabilities(q->crypto_profile,
+ t->crypto_profile);
+ dm_destroy_crypto_profile(t->crypto_profile);
}
- t->ksm = NULL;
+ t->crypto_profile = NULL;
}
#else /* CONFIG_BLK_INLINE_ENCRYPTION */
-static int dm_table_construct_keyslot_manager(struct dm_table *t)
+static int dm_table_construct_crypto_profile(struct dm_table *t)
{
return 0;
}
-void dm_destroy_keyslot_manager(struct blk_keyslot_manager *ksm)
+void dm_destroy_crypto_profile(struct blk_crypto_profile *profile)
{
}
-static void dm_table_destroy_keyslot_manager(struct dm_table *t)
+static void dm_table_destroy_crypto_profile(struct dm_table *t)
{
}
-static void dm_update_keyslot_manager(struct request_queue *q,
- struct dm_table *t)
+static void dm_update_crypto_profile(struct request_queue *q,
+ struct dm_table *t)
{
}
@@ -1414,9 +1410,9 @@ int dm_table_complete(struct dm_table *t)
return r;
}
- r = dm_table_construct_keyslot_manager(t);
+ r = dm_table_construct_crypto_profile(t);
if (r) {
- DMERR("could not construct keyslot manager.");
+ DMERR("could not construct crypto profile.");
return r;
}
@@ -2070,7 +2066,7 @@ int dm_table_set_restrictions(struct dm_table *t, struct request_queue *q,
return r;
}
- dm_update_keyslot_manager(q, t);
+ dm_update_crypto_profile(q, t);
disk_update_readahead(t->md->disk);
return 0;
diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 249223e20d3d0..f5b4f40a7fd63 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -1668,14 +1668,14 @@ static const struct dax_operations dm_dax_ops;
static void dm_wq_work(struct work_struct *work);
#ifdef CONFIG_BLK_INLINE_ENCRYPTION
-static void dm_queue_destroy_keyslot_manager(struct request_queue *q)
+static void dm_queue_destroy_crypto_profile(struct request_queue *q)
{
- dm_destroy_keyslot_manager(q->ksm);
+ dm_destroy_crypto_profile(q->crypto_profile);
}
#else /* CONFIG_BLK_INLINE_ENCRYPTION */
-static inline void dm_queue_destroy_keyslot_manager(struct request_queue *q)
+static inline void dm_queue_destroy_crypto_profile(struct request_queue *q)
{
}
#endif /* !CONFIG_BLK_INLINE_ENCRYPTION */
@@ -1701,7 +1701,7 @@ static void cleanup_mapped_device(struct mapped_device *md)
dm_sysfs_exit(md);
del_gendisk(md->disk);
}
- dm_queue_destroy_keyslot_manager(md->queue);
+ dm_queue_destroy_crypto_profile(md->queue);
blk_cleanup_disk(md->disk);
}
diff --git a/drivers/mmc/core/crypto.c b/drivers/mmc/core/crypto.c
index 67557808cada5..fec4fbf16a5b6 100644
--- a/drivers/mmc/core/crypto.c
+++ b/drivers/mmc/core/crypto.c
@@ -16,13 +16,13 @@ void mmc_crypto_set_initial_state(struct mmc_host *host)
{
/* Reset might clear all keys, so reprogram all the keys. */
if (host->caps2 & MMC_CAP2_CRYPTO)
- blk_ksm_reprogram_all_keys(&host->ksm);
+ blk_crypto_reprogram_all_keys(&host->crypto_profile);
}
void mmc_crypto_setup_queue(struct request_queue *q, struct mmc_host *host)
{
if (host->caps2 & MMC_CAP2_CRYPTO)
- blk_ksm_register(&host->ksm, q);
+ blk_crypto_register(&host->crypto_profile, q);
}
EXPORT_SYMBOL_GPL(mmc_crypto_setup_queue);
@@ -30,12 +30,15 @@ void mmc_crypto_prepare_req(struct mmc_queue_req *mqrq)
{
struct request *req = mmc_queue_req_to_req(mqrq);
struct mmc_request *mrq = &mqrq->brq.mrq;
+ struct blk_crypto_keyslot *keyslot;
if (!req->crypt_ctx)
return;
mrq->crypto_ctx = req->crypt_ctx;
- if (req->crypt_keyslot)
- mrq->crypto_key_slot = blk_ksm_get_slot_idx(req->crypt_keyslot);
+
+ keyslot = req->crypt_keyslot;
+ if (keyslot)
+ mrq->crypto_key_slot = blk_crypto_keyslot_index(keyslot);
}
EXPORT_SYMBOL_GPL(mmc_crypto_prepare_req);
diff --git a/drivers/mmc/host/cqhci-crypto.c b/drivers/mmc/host/cqhci-crypto.c
index 628bbfaf83124..d5f4b6972f63e 100644
--- a/drivers/mmc/host/cqhci-crypto.c
+++ b/drivers/mmc/host/cqhci-crypto.c
@@ -23,9 +23,10 @@ static const struct cqhci_crypto_alg_entry {
};
static inline struct cqhci_host *
-cqhci_host_from_ksm(struct blk_keyslot_manager *ksm)
+cqhci_host_from_crypto_profile(struct blk_crypto_profile *profile)
{
- struct mmc_host *mmc = container_of(ksm, struct mmc_host, ksm);
+ struct mmc_host *mmc =
+ container_of(profile, struct mmc_host, crypto_profile);
return mmc->cqe_private;
}
@@ -57,12 +58,12 @@ static int cqhci_crypto_program_key(struct cqhci_host *cq_host,
return 0;
}
-static int cqhci_crypto_keyslot_program(struct blk_keyslot_manager *ksm,
+static int cqhci_crypto_keyslot_program(struct blk_crypto_profile *profile,
const struct blk_crypto_key *key,
unsigned int slot)
{
- struct cqhci_host *cq_host = cqhci_host_from_ksm(ksm);
+ struct cqhci_host *cq_host = cqhci_host_from_crypto_profile(profile);
const union cqhci_crypto_cap_entry *ccap_array =
cq_host->crypto_cap_array;
const struct cqhci_crypto_alg_entry *alg =
@@ -115,11 +116,11 @@ static int cqhci_crypto_clear_keyslot(struct cqhci_host *cq_host, int slot)
return cqhci_crypto_program_key(cq_host, &cfg, slot);
}
-static int cqhci_crypto_keyslot_evict(struct blk_keyslot_manager *ksm,
+static int cqhci_crypto_keyslot_evict(struct blk_crypto_profile *profile,
const struct blk_crypto_key *key,
unsigned int slot)
{
- struct cqhci_host *cq_host = cqhci_host_from_ksm(ksm);
+ struct cqhci_host *cq_host = cqhci_host_from_crypto_profile(profile);
return cqhci_crypto_clear_keyslot(cq_host, slot);
}
@@ -132,7 +133,7 @@ static int cqhci_crypto_keyslot_evict(struct blk_keyslot_manager *ksm,
* "enabled" when these are called, i.e. CQHCI_ENABLE might not be set in the
* CQHCI_CFG register. But the hardware allows that.
*/
-static const struct blk_ksm_ll_ops cqhci_ksm_ops = {
+static const struct blk_crypto_ll_ops cqhci_crypto_ops = {
.keyslot_program = cqhci_crypto_keyslot_program,
.keyslot_evict = cqhci_crypto_keyslot_evict,
};
@@ -157,8 +158,8 @@ cqhci_find_blk_crypto_mode(union cqhci_crypto_cap_entry cap)
*
* If the driver previously set MMC_CAP2_CRYPTO and the CQE declares
* CQHCI_CAP_CS, initialize the crypto support. This involves reading the
- * crypto capability registers, initializing the keyslot manager, clearing all
- * keyslots, and enabling 128-bit task descriptors.
+ * crypto capability registers, initializing the blk_crypto_profile, clearing
+ * all keyslots, and enabling 128-bit task descriptors.
*
* Return: 0 if crypto was initialized or isn't supported; whether
* MMC_CAP2_CRYPTO remains set indicates which one of those cases it is.
@@ -168,7 +169,7 @@ int cqhci_crypto_init(struct cqhci_host *cq_host)
{
struct mmc_host *mmc = cq_host->mmc;
struct device *dev = mmc_dev(mmc);
- struct blk_keyslot_manager *ksm = &mmc->ksm;
+ struct blk_crypto_profile *profile = &mmc->crypto_profile;
unsigned int num_keyslots;
unsigned int cap_idx;
enum blk_crypto_mode_num blk_mode_num;
@@ -199,15 +200,15 @@ int cqhci_crypto_init(struct cqhci_host *cq_host)
*/
num_keyslots = cq_host->crypto_capabilities.config_count + 1;
- err = devm_blk_ksm_init(dev, ksm, num_keyslots);
+ err = devm_blk_crypto_profile_init(dev, profile, num_keyslots);
if (err)
goto out;
- ksm->ksm_ll_ops = cqhci_ksm_ops;
- ksm->dev = dev;
+ profile->ll_ops = cqhci_crypto_ops;
+ profile->dev = dev;
/* Unfortunately, CQHCI crypto only supports 32 DUN bits. */
- ksm->max_dun_bytes_supported = 4;
+ profile->max_dun_bytes_supported = 4;
/*
* Cache all the crypto capabilities and advertise the supported crypto
@@ -223,7 +224,7 @@ int cqhci_crypto_init(struct cqhci_host *cq_host)
cq_host->crypto_cap_array[cap_idx]);
if (blk_mode_num == BLK_ENCRYPTION_MODE_INVALID)
continue;
- ksm->crypto_modes_supported[blk_mode_num] |=
+ profile->modes_supported[blk_mode_num] |=
cq_host->crypto_cap_array[cap_idx].sdus_mask * 512;
}
diff --git a/drivers/scsi/ufs/ufshcd-crypto.c b/drivers/scsi/ufs/ufshcd-crypto.c
index d70cdcd35e435..67402baf6faee 100644
--- a/drivers/scsi/ufs/ufshcd-crypto.c
+++ b/drivers/scsi/ufs/ufshcd-crypto.c
@@ -48,11 +48,12 @@ static int ufshcd_program_key(struct ufs_hba *hba,
return err;
}
-static int ufshcd_crypto_keyslot_program(struct blk_keyslot_manager *ksm,
+static int ufshcd_crypto_keyslot_program(struct blk_crypto_profile *profile,
const struct blk_crypto_key *key,
unsigned int slot)
{
- struct ufs_hba *hba = container_of(ksm, struct ufs_hba, ksm);
+ struct ufs_hba *hba =
+ container_of(profile, struct ufs_hba, crypto_profile);
const union ufs_crypto_cap_entry *ccap_array = hba->crypto_cap_array;
const struct ufs_crypto_alg_entry *alg =
&ufs_crypto_algs[key->crypto_cfg.crypto_mode];
@@ -105,11 +106,12 @@ static int ufshcd_clear_keyslot(struct ufs_hba *hba, int slot)
return ufshcd_program_key(hba, &cfg, slot);
}
-static int ufshcd_crypto_keyslot_evict(struct blk_keyslot_manager *ksm,
+static int ufshcd_crypto_keyslot_evict(struct blk_crypto_profile *profile,
const struct blk_crypto_key *key,
unsigned int slot)
{
- struct ufs_hba *hba = container_of(ksm, struct ufs_hba, ksm);
+ struct ufs_hba *hba =
+ container_of(profile, struct ufs_hba, crypto_profile);
return ufshcd_clear_keyslot(hba, slot);
}
@@ -120,11 +122,11 @@ bool ufshcd_crypto_enable(struct ufs_hba *hba)
return false;
/* Reset might clear all keys, so reprogram all the keys. */
- blk_ksm_reprogram_all_keys(&hba->ksm);
+ blk_crypto_reprogram_all_keys(&hba->crypto_profile);
return true;
}
-static const struct blk_ksm_ll_ops ufshcd_ksm_ops = {
+static const struct blk_crypto_ll_ops ufshcd_crypto_ops = {
.keyslot_program = ufshcd_crypto_keyslot_program,
.keyslot_evict = ufshcd_crypto_keyslot_evict,
};
@@ -179,15 +181,16 @@ int ufshcd_hba_init_crypto_capabilities(struct ufs_hba *hba)
}
/* The actual number of configurations supported is (CFGC+1) */
- err = devm_blk_ksm_init(hba->dev, &hba->ksm,
- hba->crypto_capabilities.config_count + 1);
+ err = devm_blk_crypto_profile_init(
+ hba->dev, &hba->crypto_profile,
+ hba->crypto_capabilities.config_count + 1);
if (err)
goto out;
- hba->ksm.ksm_ll_ops = ufshcd_ksm_ops;
+ hba->crypto_profile.ll_ops = ufshcd_crypto_ops;
/* UFS only supports 8 bytes for any DUN */
- hba->ksm.max_dun_bytes_supported = 8;
- hba->ksm.dev = hba->dev;
+ hba->crypto_profile.max_dun_bytes_supported = 8;
+ hba->crypto_profile.dev = hba->dev;
/*
* Cache all the UFS crypto capabilities and advertise the supported
@@ -202,7 +205,7 @@ int ufshcd_hba_init_crypto_capabilities(struct ufs_hba *hba)
blk_mode_num = ufshcd_find_blk_crypto_mode(
hba->crypto_cap_array[cap_idx]);
if (blk_mode_num != BLK_ENCRYPTION_MODE_INVALID)
- hba->ksm.crypto_modes_supported[blk_mode_num] |=
+ hba->crypto_profile.modes_supported[blk_mode_num] |=
hba->crypto_cap_array[cap_idx].sdus_mask * 512;
}
@@ -230,9 +233,8 @@ void ufshcd_init_crypto(struct ufs_hba *hba)
ufshcd_clear_keyslot(hba, slot);
}
-void ufshcd_crypto_setup_rq_keyslot_manager(struct ufs_hba *hba,
- struct request_queue *q)
+void ufshcd_crypto_register(struct ufs_hba *hba, struct request_queue *q)
{
if (hba->caps & UFSHCD_CAP_CRYPTO)
- blk_ksm_register(&hba->ksm, q);
+ blk_crypto_register(&hba->crypto_profile, q);
}
diff --git a/drivers/scsi/ufs/ufshcd-crypto.h b/drivers/scsi/ufs/ufshcd-crypto.h
index 78a58e788dff9..e18c012768732 100644
--- a/drivers/scsi/ufs/ufshcd-crypto.h
+++ b/drivers/scsi/ufs/ufshcd-crypto.h
@@ -18,7 +18,7 @@ static inline void ufshcd_prepare_lrbp_crypto(struct request *rq,
return;
}
- lrbp->crypto_key_slot = blk_ksm_get_slot_idx(rq->crypt_keyslot);
+ lrbp->crypto_key_slot = blk_crypto_keyslot_index(rq->crypt_keyslot);
lrbp->data_unit_num = rq->crypt_ctx->bc_dun[0];
}
@@ -40,8 +40,7 @@ int ufshcd_hba_init_crypto_capabilities(struct ufs_hba *hba);
void ufshcd_init_crypto(struct ufs_hba *hba);
-void ufshcd_crypto_setup_rq_keyslot_manager(struct ufs_hba *hba,
- struct request_queue *q);
+void ufshcd_crypto_register(struct ufs_hba *hba, struct request_queue *q);
#else /* CONFIG_SCSI_UFS_CRYPTO */
@@ -64,8 +63,8 @@ static inline int ufshcd_hba_init_crypto_capabilities(struct ufs_hba *hba)
static inline void ufshcd_init_crypto(struct ufs_hba *hba) { }
-static inline void ufshcd_crypto_setup_rq_keyslot_manager(struct ufs_hba *hba,
- struct request_queue *q) { }
+static inline void ufshcd_crypto_register(struct ufs_hba *hba,
+ struct request_queue *q) { }
#endif /* CONFIG_SCSI_UFS_CRYPTO */
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 3841ab49f5560..2782e7e2c9b7e 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -5017,7 +5017,7 @@ static int ufshcd_slave_configure(struct scsi_device *sdev)
else if (ufshcd_is_rpm_autosuspend_allowed(hba))
sdev->rpm_autosuspend = 1;
- ufshcd_crypto_setup_rq_keyslot_manager(hba, q);
+ ufshcd_crypto_register(hba, q);
return 0;
}
diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
index 0f9cbe74642fe..df5439b122085 100644
--- a/drivers/scsi/ufs/ufshcd.h
+++ b/drivers/scsi/ufs/ufshcd.h
@@ -764,7 +764,7 @@ struct ufs_hba_monitor {
* @crypto_capabilities: Content of crypto capabilities register (0x100)
* @crypto_cap_array: Array of crypto capabilities
* @crypto_cfg_register: Start of the crypto cfg array
- * @ksm: the keyslot manager tied to this hba
+ * @crypto_profile: the crypto profile of this hba (if applicable)
*/
struct ufs_hba {
void __iomem *mmio_base;
@@ -905,7 +905,7 @@ struct ufs_hba {
union ufs_crypto_capabilities crypto_capabilities;
union ufs_crypto_cap_entry *crypto_cap_array;
u32 crypto_cfg_register;
- struct blk_keyslot_manager ksm;
+ struct blk_crypto_profile crypto_profile;
#endif
#ifdef CONFIG_DEBUG_FS
struct dentry *debugfs_root;
diff --git a/include/linux/blk-crypto-profile.h b/include/linux/blk-crypto-profile.h
index a27605e2f8260..e967b189d81db 100644
--- a/include/linux/blk-crypto-profile.h
+++ b/include/linux/blk-crypto-profile.h
@@ -3,67 +3,113 @@
* Copyright 2019 Google LLC
*/
-#ifndef __LINUX_KEYSLOT_MANAGER_H
-#define __LINUX_KEYSLOT_MANAGER_H
+#ifndef __LINUX_BLK_CRYPTO_PROFILE_H
+#define __LINUX_BLK_CRYPTO_PROFILE_H
#include <linux/bio.h>
#include <linux/blk-crypto.h>
-struct blk_keyslot_manager;
+struct blk_crypto_profile;
/**
- * struct blk_ksm_ll_ops - functions to manage keyslots in hardware
- * @keyslot_program: Program the specified key into the specified slot in the
- * inline encryption hardware.
- * @keyslot_evict: Evict key from the specified keyslot in the hardware.
- * The key is provided so that e.g. dm layers can evict
- * keys from the devices that they map over.
- * Returns 0 on success, -errno otherwise.
+ * struct blk_crypto_ll_ops - functions to control inline encryption hardware
*
- * This structure should be provided by storage device drivers when they set up
- * a keyslot manager - this structure holds the function ptrs that the keyslot
- * manager will use to manipulate keyslots in the hardware.
+ * Low-level operations for controlling inline encryption hardware. This
+ * interface must be implemented by storage drivers that support inline
+ * encryption. All functions may sleep, are serialized by profile->lock, and
+ * are never called while profile->dev (if set) is runtime-suspended.
*/
-struct blk_ksm_ll_ops {
- int (*keyslot_program)(struct blk_keyslot_manager *ksm,
+struct blk_crypto_ll_ops {
+
+ /**
+ * @keyslot_program: Program a key into the inline encryption hardware.
+ *
+ * Program @key into the specified @slot in the inline encryption
+ * hardware, overwriting any key that the keyslot may already contain.
+ * The keyslot is guaranteed to not be in-use by any I/O.
+ *
+ * This is required if the device has keyslots. Otherwise (i.e. if the
+ * device is a layered device, or if the device is real hardware that
+ * simply doesn't have the concept of keyslots) it is never called.
+ *
+ * Must return 0 on success, or -errno on failure.
+ */
+ int (*keyslot_program)(struct blk_crypto_profile *profile,
const struct blk_crypto_key *key,
unsigned int slot);
- int (*keyslot_evict)(struct blk_keyslot_manager *ksm,
+
+ /**
+ * @keyslot_evict: Evict a key from the inline encryption hardware.
+ *
+ * If the device has keyslots, this function must evict the key from the
+ * specified @slot. The slot will contain @key, but there should be no
+ * need for the @key argument to be used as @slot should be sufficient.
+ * The keyslot is guaranteed to not be in-use by any I/O.
+ *
+ * If the device doesn't have keyslots itself, this function must evict
+ * @key from any underlying devices. @slot won't be valid in this case.
+ *
+ * If there are no keyslots and no underlying devices, this function
+ * isn't required.
+ *
+ * Must return 0 on success, or -errno on failure.
+ */
+ int (*keyslot_evict)(struct blk_crypto_profile *profile,
const struct blk_crypto_key *key,
unsigned int slot);
};
-struct blk_keyslot_manager {
- /*
- * The struct blk_ksm_ll_ops that this keyslot manager will use
- * to perform operations like programming and evicting keys on the
- * device
+/**
+ * struct blk_crypto_profile - inline encryption profile for a device
+ *
+ * This struct contains a storage device's inline encryption capabilities (e.g.
+ * the supported crypto algorithms), driver-provided functions to control the
+ * inline encryption hardware (e.g. programming and evicting keys), and optional
+ * device-independent keyslot management data.
+ */
+struct blk_crypto_profile {
+
+ /* public: Drivers must initialize the following fields. */
+
+ /**
+ * @ll_ops: Driver-provided functions to control the inline encryption
+ * hardware, e.g. program and evict keys.
*/
- struct blk_ksm_ll_ops ksm_ll_ops;
+ struct blk_crypto_ll_ops ll_ops;
- /*
- * The maximum number of bytes supported for specifying the data unit
- * number.
+ /**
+ * @max_dun_bytes_supported: The maximum number of bytes supported for
+ * specifying the data unit number (DUN). Specifically, the range of
+ * supported DUNs is 0 through (1 << (8 * max_dun_bytes_supported)) - 1.
*/
unsigned int max_dun_bytes_supported;
- /*
- * Array of size BLK_ENCRYPTION_MODE_MAX of bitmasks that represents
- * whether a crypto mode and data unit size are supported. The i'th
- * bit of crypto_mode_supported[crypto_mode] is set iff a data unit
- * size of (1 << i) is supported. We only support data unit sizes
- * that are powers of 2.
+ /**
+ * @modes_supported: Array of bitmasks that specifies whether
+ * each combination of crypto mode and data unit size is supported.
+ * Specifically, the i'th bit of crypto_mode_supported[crypto_mode] is
+ * set if crypto_mode can be used with a data unit size of (1 << i).
+ * Note that we can only support data unit sizes that are powers of 2.
*/
- unsigned int crypto_modes_supported[BLK_ENCRYPTION_MODE_MAX];
+ unsigned int modes_supported[BLK_ENCRYPTION_MODE_MAX];
- /* Device for runtime power management (NULL if none) */
+ /**
+ * @dev: An optional device for runtime power management. If the driver
+ * provides this device, it will be runtime-resumed before any function
+ * in @ll_ops is called and will remain resumed during the call.
+ */
struct device *dev;
- /* Here onwards are *private* fields for internal keyslot manager use */
+ /* private: The following fields shouldn't be accessed by drivers. */
+ /* Number of keyslots, or 0 if not applicable */
unsigned int num_slots;
- /* Protects programming and evicting keys from the device */
+ /*
+ * Serializes all calls to functions in @ll_ops, as well as all changes
+ * to @slot_hashtable. This can also be taken in read mode to look up
+ * keyslots while ensuring that they can't be concurrently changed.
+ */
struct rw_semaphore lock;
/* List of idle slots, with least recently used slot at front */
@@ -80,41 +126,41 @@ struct blk_keyslot_manager {
unsigned int log_slot_ht_size;
/* Per-keyslot data */
- struct blk_ksm_keyslot *slots;
+ struct blk_crypto_keyslot *slots;
};
-int blk_ksm_init(struct blk_keyslot_manager *ksm, unsigned int num_slots);
-
-int devm_blk_ksm_init(struct device *dev, struct blk_keyslot_manager *ksm,
- unsigned int num_slots);
+int blk_crypto_profile_init(struct blk_crypto_profile *profile,
+ unsigned int num_slots);
-blk_status_t blk_ksm_get_slot_for_key(struct blk_keyslot_manager *ksm,
- const struct blk_crypto_key *key,
- struct blk_ksm_keyslot **slot_ptr);
+int devm_blk_crypto_profile_init(struct device *dev,
+ struct blk_crypto_profile *profile,
+ unsigned int num_slots);
-unsigned int blk_ksm_get_slot_idx(struct blk_ksm_keyslot *slot);
+unsigned int blk_crypto_keyslot_index(const struct blk_crypto_keyslot *slot);
-void blk_ksm_put_slot(struct blk_ksm_keyslot *slot);
+blk_status_t blk_crypto_get_keyslot(struct blk_crypto_profile *profile,
+ const struct blk_crypto_key *key,
+ struct blk_crypto_keyslot **slot_ptr);
-bool blk_ksm_crypto_cfg_supported(struct blk_keyslot_manager *ksm,
- const struct blk_crypto_config *cfg);
+void blk_crypto_put_keyslot(struct blk_crypto_keyslot *slot);
-int blk_ksm_evict_key(struct blk_keyslot_manager *ksm,
- const struct blk_crypto_key *key);
+bool __blk_crypto_cfg_supported(struct blk_crypto_profile *profile,
+ const struct blk_crypto_config *cfg);
-void blk_ksm_reprogram_all_keys(struct blk_keyslot_manager *ksm);
+int __blk_crypto_evict_key(struct blk_crypto_profile *profile,
+ const struct blk_crypto_key *key);
-void blk_ksm_destroy(struct blk_keyslot_manager *ksm);
+void blk_crypto_reprogram_all_keys(struct blk_crypto_profile *profile);
-void blk_ksm_intersect_modes(struct blk_keyslot_manager *parent,
- const struct blk_keyslot_manager *child);
+void blk_crypto_profile_destroy(struct blk_crypto_profile *profile);
-void blk_ksm_init_passthrough(struct blk_keyslot_manager *ksm);
+void blk_crypto_intersect_capabilities(struct blk_crypto_profile *parent,
+ const struct blk_crypto_profile *child);
-bool blk_ksm_is_superset(struct blk_keyslot_manager *ksm_superset,
- struct blk_keyslot_manager *ksm_subset);
+bool blk_crypto_has_capabilities(const struct blk_crypto_profile *target,
+ const struct blk_crypto_profile *reference);
-void blk_ksm_update_capabilities(struct blk_keyslot_manager *target_ksm,
- struct blk_keyslot_manager *reference_ksm);
+void blk_crypto_update_capabilities(struct blk_crypto_profile *dst,
+ const struct blk_crypto_profile *src);
-#endif /* __LINUX_KEYSLOT_MANAGER_H */
+#endif /* __LINUX_BLK_CRYPTO_PROFILE_H */
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 12b9dbcc980ee..356567520c725 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -37,7 +37,7 @@ struct pr_ops;
struct rq_qos;
struct blk_queue_stats;
struct blk_stat_callback;
-struct blk_keyslot_manager;
+struct blk_crypto_profile;
#define BLKDEV_MIN_RQ 4
#define BLKDEV_MAX_RQ 128 /* Default maximum */
@@ -211,7 +211,7 @@ struct request {
#ifdef CONFIG_BLK_INLINE_ENCRYPTION
struct bio_crypt_ctx *crypt_ctx;
- struct blk_ksm_keyslot *crypt_keyslot;
+ struct blk_crypto_keyslot *crypt_keyslot;
#endif
unsigned short write_hint;
@@ -444,8 +444,7 @@ struct request_queue {
unsigned int dma_alignment;
#ifdef CONFIG_BLK_INLINE_ENCRYPTION
- /* Inline crypto capabilities */
- struct blk_keyslot_manager *ksm;
+ struct blk_crypto_profile *crypto_profile;
#endif
unsigned int rq_timeout;
@@ -1813,19 +1812,20 @@ static inline struct bio_vec *rq_integrity_vec(struct request *rq)
#ifdef CONFIG_BLK_INLINE_ENCRYPTION
-bool blk_ksm_register(struct blk_keyslot_manager *ksm, struct request_queue *q);
+bool blk_crypto_register(struct blk_crypto_profile *profile,
+ struct request_queue *q);
-void blk_ksm_unregister(struct request_queue *q);
+void blk_crypto_unregister(struct request_queue *q);
#else /* CONFIG_BLK_INLINE_ENCRYPTION */
-static inline bool blk_ksm_register(struct blk_keyslot_manager *ksm,
- struct request_queue *q)
+static inline bool blk_crypto_register(struct blk_crypto_profile *profile,
+ struct request_queue *q)
{
return true;
}
-static inline void blk_ksm_unregister(struct request_queue *q) { }
+static inline void blk_crypto_unregister(struct request_queue *q) { }
#endif /* CONFIG_BLK_INLINE_ENCRYPTION */
diff --git a/include/linux/device-mapper.h b/include/linux/device-mapper.h
index 114553b487ef4..a7df155ea49b8 100644
--- a/include/linux/device-mapper.h
+++ b/include/linux/device-mapper.h
@@ -576,9 +576,9 @@ struct dm_table *dm_swap_table(struct mapped_device *md,
struct dm_table *t);
/*
- * Table keyslot manager functions
+ * Table blk_crypto_profile functions
*/
-void dm_destroy_keyslot_manager(struct blk_keyslot_manager *ksm);
+void dm_destroy_crypto_profile(struct blk_crypto_profile *profile);
/*-----------------------------------------------------------------
* Macros.
diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h
index 725b1de417673..52eae8c45b8d6 100644
--- a/include/linux/mmc/host.h
+++ b/include/linux/mmc/host.h
@@ -492,7 +492,7 @@ struct mmc_host {
/* Inline encryption support */
#ifdef CONFIG_MMC_CRYPTO
- struct blk_keyslot_manager ksm;
+ struct blk_crypto_profile crypto_profile;
#endif
/* Host Software Queue support */
--
2.33.0
^ permalink raw reply related [flat|nested] 17+ messages in thread* [PATCH 5/5] blk-crypto: update inline encryption documentation
2021-09-13 1:31 [PATCH 0/5] blk-crypto cleanups Eric Biggers
` (3 preceding siblings ...)
2021-09-13 1:31 ` [PATCH 4/5] blk-crypto: rename blk_keyslot_manager to blk_crypto_profile Eric Biggers
@ 2021-09-13 1:31 ` Eric Biggers
4 siblings, 0 replies; 17+ messages in thread
From: Eric Biggers @ 2021-09-13 1:31 UTC (permalink / raw)
To: linux-block; +Cc: linux-mmc, linux-scsi, dm-devel, Satya Tangirala
From: Eric Biggers <ebiggers@google.com>
Rework most of inline-encryption.rst to be easier to follow, to correct
some information, to add some important details and remove some
unimportant details, and to take into account the renaming from
blk_keyslot_manager to blk_crypto_profile.
Signed-off-by: Eric Biggers <ebiggers@google.com>
---
Documentation/block/inline-encryption.rst | 439 ++++++++++++----------
1 file changed, 236 insertions(+), 203 deletions(-)
diff --git a/Documentation/block/inline-encryption.rst b/Documentation/block/inline-encryption.rst
index 7f9b40d6b416b..2af53915654a9 100644
--- a/Documentation/block/inline-encryption.rst
+++ b/Documentation/block/inline-encryption.rst
@@ -8,229 +8,262 @@ Background
==========
Inline encryption hardware sits logically between memory and the disk, and can
-en/decrypt data as it goes in/out of the disk. Inline encryption hardware has a
-fixed number of "keyslots" - slots into which encryption contexts (i.e. the
-encryption key, encryption algorithm, data unit size) can be programmed by the
-kernel at any time. Each request sent to the disk can be tagged with the index
-of a keyslot (and also a data unit number to act as an encryption tweak), and
-the inline encryption hardware will en/decrypt the data in the request with the
-encryption context programmed into that keyslot. This is very different from
-full disk encryption solutions like self encrypting drives/TCG OPAL/ATA
-Security standards, since with inline encryption, any block on disk could be
-encrypted with any encryption context the kernel chooses.
-
+en/decrypt data as it goes in/out of the disk. For each I/O request, software
+can control exactly how the inline encryption hardware will en/decrypt the data
+in terms of key, algorithm, data unit size (the granularity of en/decryption),
+and data unit number (a value that determines the initialization vector(s)).
+
+Some inline encryption hardware accepts the key, algorithm, and data unit size
+directly in I/O requests. However, most inline encryption hardware instead has
+a fixed number of "keyslots" and requires that the key, algorithm, and data unit
+size first be programmed into a keyslot. I/O requests then just reference
+keyslot indices.
+
+Note that inline encryption hardware is very different from "self-encrypting
+drives", such as those based on the TCG Opal or ATA Security standards.
+Self-encrypting drives don't provide fine-grained software control of encryption
+and provide no way to verify the correctness of the resulting ciphertext. In
+contrast, inline encryption hardware provides fine-grained control of
+encryption, including the choice of key and initialization vector for each
+sector, and can be tested for correctness.
Objective
=========
-We want to support inline encryption (IE) in the kernel.
-To allow for testing, we also want a crypto API fallback when actual
-IE hardware is absent. We also want IE to work with layered devices
-like dm and loopback (i.e. we want to be able to use the IE hardware
-of the underlying devices if present, or else fall back to crypto API
-en/decryption).
-
+We want to support inline encryption in the kernel. To make testing easier, we
+also want support for falling back to the kernel crypto API when actual inline
+encryption hardware is absent. We also want inline encryption to work with
+layered devices like device-mapper and loopback (i.e. we want to be able to use
+the inline encryption hardware of the underlying devices if present, or else
+fall back to crypto API en/decryption).
Constraints and notes
=====================
-- IE hardware has a limited number of "keyslots" that can be programmed
- with an encryption context (key, algorithm, data unit size, etc.) at any time.
- One can specify a keyslot in a data request made to the device, and the
- device will en/decrypt the data using the encryption context programmed into
- that specified keyslot. When possible, we want to make multiple requests with
- the same encryption context share the same keyslot.
-
-- We need a way for upper layers like filesystems to specify an encryption
- context to use for en/decrypting a struct bio, and a device driver (like UFS)
- needs to be able to use that encryption context when it processes the bio.
-
-- We need a way for device drivers to expose their inline encryption
- capabilities in a unified way to the upper layers.
-
-
-Design
-======
-
-We add a struct bio_crypt_ctx to struct bio that can
-represent an encryption context, because we need to be able to pass this
-encryption context from the upper layers (like the fs layer) to the
-device driver to act upon.
-
-While IE hardware works on the notion of keyslots, the FS layer has no
-knowledge of keyslots - it simply wants to specify an encryption context to
-use while en/decrypting a bio.
-
-We introduce a keyslot manager (KSM) that handles the translation from
-encryption contexts specified by the FS to keyslots on the IE hardware.
-This KSM also serves as the way IE hardware can expose its capabilities to
-upper layers. The generic mode of operation is: each device driver that wants
-to support IE will construct a KSM and set it up in its struct request_queue.
-Upper layers that want to use IE on this device can then use this KSM in
-the device's struct request_queue to translate an encryption context into
-a keyslot. The presence of the KSM in the request queue shall be used to mean
-that the device supports IE.
-
-The KSM uses refcounts to track which keyslots are idle (either they have no
-encryption context programmed, or there are no in-flight struct bios
-referencing that keyslot). When a new encryption context needs a keyslot, it
-tries to find a keyslot that has already been programmed with the same
-encryption context, and if there is no such keyslot, it evicts the least
-recently used idle keyslot and programs the new encryption context into that
-one. If no idle keyslots are available, then the caller will sleep until there
-is at least one.
-
-
-blk-mq changes, other block layer changes and blk-crypto-fallback
-=================================================================
-
-We add a pointer to a ``bi_crypt_context`` and ``keyslot`` to
-struct request. These will be referred to as the ``crypto fields``
-for the request. This ``keyslot`` is the keyslot into which the
-``bi_crypt_context`` has been programmed in the KSM of the ``request_queue``
-that this request is being sent to.
-
-We introduce ``block/blk-crypto-fallback.c``, which allows upper layers to remain
-blissfully unaware of whether or not real inline encryption hardware is present
-underneath. When a bio is submitted with a target ``request_queue`` that doesn't
-support the encryption context specified with the bio, the block layer will
-en/decrypt the bio with the blk-crypto-fallback.
-
-If the bio is a ``WRITE`` bio, a bounce bio is allocated, and the data in the bio
-is encrypted stored in the bounce bio - blk-mq will then proceed to process the
-bounce bio as if it were not encrypted at all (except when blk-integrity is
-concerned). ``blk-crypto-fallback`` sets the bounce bio's ``bi_end_io`` to an
-internal function that cleans up the bounce bio and ends the original bio.
-
-If the bio is a ``READ`` bio, the bio's ``bi_end_io`` (and also ``bi_private``)
-is saved and overwritten by ``blk-crypto-fallback`` to
-``bio_crypto_fallback_decrypt_bio``. The bio's ``bi_crypt_context`` is also
-overwritten with ``NULL``, so that to the rest of the stack, the bio looks
-as if it was a regular bio that never had an encryption context specified.
-``bio_crypto_fallback_decrypt_bio`` will decrypt the bio, restore the original
-``bi_end_io`` (and also ``bi_private``) and end the bio again.
-
-Regardless of whether real inline encryption hardware is used or the
+- We need a way for upper layers (e.g. filesystems) to specify an encryption
+ context to use for en/decrypting a bio, and device drivers (e.g. UFSHCD) need
+ to be able to use that encryption context when they process the request.
+ Encryption contexts also introduce constraints on bio merging; the block layer
+ needs to be aware of these constraints.
+
+- Different inline encryption hardware has different supported algorithms,
+ supported data unit sizes, maximum data unit numbers, etc. We call these
+ properties the "crypto capabilities". We need a way for device drivers to
+ advertise crypto capabilities to upper layers in a generic way.
+
+- Inline encryption hardware usually (but not always) requires that keys be
+ programmed into keyslots before being used. Since programming keyslots may be
+ slow and there may not be very many keyslots, we shouldn't just program the
+ key for every I/O request, but rather keep track of which keys are in the
+ keyslots and reuse an already-programmed keyslot when possible.
+
+- Upper layers typically define a specific end-of-life for crypto keys, e.g.
+ when an encrypted directory is locked or when a crypto mapping is torn down.
+ At these times, keys are wiped from memory. We must provide a way for upper
+ layers to also evict keys from any keyslots they are present in.
+
+- When possible, device-mapper devices must be able to pass through the inline
+ encryption support of their underlying devices. However, it doesn't make
+ sense for device-mapper devices to have keyslots themselves.
+
+Basic design
+============
+
+We introduce ``struct blk_crypto_key`` to represent an inline encryption key and
+how it will be used. This includes the actual bytes of the key; the size of the
+key; the algorithm and data unit size the key will be used with; and the number
+of bytes needed to represent the maximum data unit number the key will be used
+with.
+
+We introduce ``struct bio_crypt_ctx`` to represent an encryption context. It
+contains a data unit number and a pointer to a blk_crypto_key. We add pointers
+to a bio_crypt_ctx to ``struct bio`` and ``struct request``; this allows users
+of the block layer (e.g. filesystems) to provide an encryption context when
+creating a bio and have it be passed down the stack for processing by the block
+layer and device drivers. Note that the encryption context doesn't explicitly
+say whether to encrypt or decrypt, as that is implicit from the direction of the
+bio; WRITE means encrypt, and READ means decrypt.
+
+We also introduce ``struct blk_crypto_profile`` to contain all generic inline
+encryption-related state for a particular inline encryption device. The
+blk_crypto_profile serves as the way that drivers for inline encryption hardware
+advertise their crypto capabilities and provide certain functions (e.g.,
+functions to program and evict keys) to upper layers. Each device driver that
+wants to support inline encryption will construct a blk_crypto_profile, then
+associate it with the disk's request_queue.
+
+The blk_crypto_profile also manages the hardware's keyslots, when applicable.
+This happens in the block layer, so that users of the block layer can just
+specify encryption contexts and don't need to know about keyslots at all, nor do
+device drivers need to care about most details of keyslot management.
+
+Specifically, for each keyslot, the block layer (via the blk_crypto_profile)
+keeps track of which blk_crypto_key that keyslot contains (if any), and how many
+in-flight I/O requests are using it. When the block layer creates a ``struct
+request`` for a bio that has an encryption context, it grabs a keyslot that
+already contains the key if possible. Otherwise it waits for an idle keyslot (a
+keyslot that was either never used or one that isn't in-use by any I/O), then
+programs the key into the least-recently-used idle keyslot using the function
+the device driver provided. In both cases, the resulting keyslot is stored in
+the ``crypt_keyslot`` field of the request, where it is then accessible to
+device drivers, and is released after the request completes.
+
+``struct request`` also contains a pointer to the original bio_crypt_ctx, in
+addition to the keyslot. Requests can be built from multiple bios, and the
+block layer must take the encryption context into account when trying to merge
+bios and requests. For two bios/requests to be merged, they must have
+compatible encryption contexts: both unencrypted, or both encrypted with the
+same key and contiguous data unit numbers. Only the encryption context for the
+first bio in a request is retained, since the remaining bios have been verified
+to be merge-compatible with the first bio.
+
+To make it possible for inline encryption to work with request_queue based
+layered devices, when a request is cloned, its encryption context is cloned as
+well. When the cloned request is submitted, it is then processed as usual; this
+includes getting a keyslot from the clone's target device if needed.
+
+blk-crypto-fallback
+===================
+
+It is desirable for the inline encryption support of upper layers (e.g.
+filesystems) to be testable without real inline encryption hardware, and
+likewise for the block layer's keyslot management logic. It is also desirable
+to allow upper layers to just always use inline encryption rather than
+implementing encryption in multiple ways.
+
+Therefore, we also introduce "blk-crypto-fallback", which is an implementation
+of inline encryption using the kernel crypto API. blk-crypto-fallback is built
+into the block layer, so it works on any block device without any special setup.
+Essentially, when a bio with an encryption context is submitted to a
+request_queue that doesn't support that encryption context, the block layer will
+handle en/decryption of the bio using blk-crypto-fallback.
+
+For encryption, the data cannot be encrypted in-place, as callers usually rely
+on it being unmodified. Instead, blk-crypto-fallback allocates bounce pages,
+fills a new bio with those bounce pages, encrypts the data into those bounce
+pages, and submits that "bounce" bio. When the bounce bio completes,
+blk-crypto-fallback completes the original bio. If the original bio is too
+large, multiple bounce bios may be required; see the code for details.
+
+For decryption, blk-crypto-fallback "wraps" the bio's completion callback
+(``bi_complete``) and private data (``bi_private``) with its own, unsets the
+bio's encryption context, then submits the bio. If the read completes
+successfully, blk-crypto-fallback restores the bio's original completion
+callback and private data, then decrypts the bio's data in-place using the
+kernel crypto API. Decryption happens from a workqueue, as it may sleep.
+Afterwards, blk-crypto-fallback completes the bio.
+
+In both cases, the bios that blk-crypto-fallback submits no longer have an
+encryption context. Therefore, lower layers only see standard unencrypted I/O.
+
+blk-crypto-fallback also defines its own blk_crypto_profile and has its own
+"keyslots"; its keyslots contain ``struct crypto_skcipher`` objects. The reason
+for this is twofold. First, it allows the keyslot management logic to be tested
+without actual inline encryption hardware. Second, similar to actual inline
+encryption hardware, the crypto API doesn't accept keys directly in requests but
+rather requires that they be set again of time, and setting keys can be
+expensive; moreover, allocating a crypto_skcipher can't happen on the I/O path
+at all due to the locks it takes. Therefore, the concept of keyslots still
+makes sense for blk-crypto-fallback.
+
+Note that regardless of whether real inline encryption hardware or
blk-crypto-fallback is used, the ciphertext written to disk (and hence the
on-disk format of data) will be the same (assuming the hardware's implementation
of the algorithm being used adheres to spec and functions correctly).
-If a ``request queue``'s inline encryption hardware claimed to support the
-encryption context specified with a bio, then it will not be handled by the
-``blk-crypto-fallback``. We will eventually reach a point in blk-mq when a
-struct request needs to be allocated for that bio. At that point,
-blk-mq tries to program the encryption context into the ``request_queue``'s
-keyslot_manager, and obtain a keyslot, which it stores in its newly added
-``keyslot`` field. This keyslot is released when the request is completed.
-
-When the first bio is added to a request, ``blk_crypto_rq_bio_prep`` is called,
-which sets the request's ``crypt_ctx`` to a copy of the bio's
-``bi_crypt_context``. bio_crypt_do_front_merge is called whenever a subsequent
-bio is merged to the front of the request, which updates the ``crypt_ctx`` of
-the request so that it matches the newly merged bio's ``bi_crypt_context``. In particular, the request keeps a copy of the ``bi_crypt_context`` of the first
-bio in its bio-list (blk-mq needs to be careful to maintain this invariant
-during bio and request merges).
-
-To make it possible for inline encryption to work with request queue based
-layered devices, when a request is cloned, its ``crypto fields`` are cloned as
-well. When the cloned request is submitted, blk-mq programs the
-``bi_crypt_context`` of the request into the clone's request_queue's keyslot
-manager, and stores the returned keyslot in the clone's ``keyslot``.
-
+blk-crypto-fallback is optional and is controlled by the
+``CONFIG_BLK_INLINE_ENCRYPTION_FALLBACK`` kernel configuration option.
API presented to users of the block layer
=========================================
-``struct blk_crypto_key`` represents a crypto key (the raw key, size of the
-key, the crypto algorithm to use, the data unit size to use, and the number of
-bytes required to represent data unit numbers that will be specified with the
-``bi_crypt_context``).
-
-``blk_crypto_init_key`` allows upper layers to initialize such a
-``blk_crypto_key``.
-
-``bio_crypt_set_ctx`` should be called on any bio that a user of
-the block layer wants en/decrypted via inline encryption (or the
-blk-crypto-fallback, if hardware support isn't available for the desired
-crypto configuration). This function takes the ``blk_crypto_key`` and the
-data unit number (DUN) to use when en/decrypting the bio.
-
-``blk_crypto_config_supported`` allows upper layers to query whether or not the
-an encryption context passed to request queue can be handled by blk-crypto
-(either by real inline encryption hardware, or by the blk-crypto-fallback).
-This is useful e.g. when blk-crypto-fallback is disabled, and the upper layer
-wants to use an algorithm that may not supported by hardware - this function
-lets the upper layer know ahead of time that the algorithm isn't supported,
-and the upper layer can fallback to something else if appropriate.
-
-``blk_crypto_start_using_key`` - Upper layers must call this function on
-``blk_crypto_key`` and a ``request_queue`` before using the key with any bio
-headed for that ``request_queue``. This function ensures that either the
-hardware supports the key's crypto settings, or the crypto API fallback has
-transforms for the needed mode allocated and ready to go. Note that this
-function may allocate an ``skcipher``, and must not be called from the data
-path, since allocating ``skciphers`` from the data path can deadlock.
-
-``blk_crypto_evict_key`` *must* be called by upper layers before a
-``blk_crypto_key`` is freed. Further, it *must* only be called only once
-there are no more in-flight requests that use that ``blk_crypto_key``.
-``blk_crypto_evict_key`` will ensure that a key is removed from any keyslots in
-inline encryption hardware that the key might have been programmed into (or the blk-crypto-fallback).
+``blk_crypto_init_key()`` allows users to initialize a blk_crypto_key.
+
+``blk_crypto_config_supported()`` allows users to check ahead of time whether
+inline encryption with particular crypto settings will work on a particular
+request_queue -- either via hardware or via blk-crypto-fallback. This function
+takes in a ``struct blk_crypto_config`` which is like blk_crypto_key, but omits
+the actual bytes of the key and instead just contains the algorithm, data unit
+size, etc. This function can be useful if blk-crypto-fallback is disabled.
+
+Users must call ``blk_crypto_start_using_key()`` before actually starting to use
+a blk_crypto_key on a request_queue (even if ``blk_crypto_config_supported()``
+was called earlier). This is needed to initialize blk-crypto-fallback if it
+will be needed. This must not be called from the data path, as this may have to
+allocate resources, which may deadlock in that case.
+
+Next, to attach an encryption context to a bio, users should call
+``bio_crypt_set_ctx()``. This function allocates a bio_crypt_ctx and attaches
+it to a bio, given the blk_crypto_key and the data unit number that will be used
+for en/decryption. Users don't need to worry about freeing the bio_crypt_ctx
+later, as that happens automatically when the bio is freed or reset.
+
+Finally, when done using inline encryption with a blk_crypto_key on a
+request_queue, users must call ``blk_crypto_evict_key()``. This ensures that
+the key is evicted from all keyslots it may be programmed into, and unlinked
+from any kernel data structures it may be linked into.
+
+In summary, for users of the block layer, the lifecycle of a blk_crypto_key is
+as follows:
+
+1. ``blk_crypto_config_supported()`` (optional)
+2. ``blk_crypto_init_key()``
+3. ``blk_crypto_start_using_key()``
+4. ``bio_crypt_set_ctx()`` (potentially many times)
+5. ``blk_crypto_evict_key()`` (after all I/O has completed)
+6. Zeroize the blk_crypto_key (this has no dedicated function)
+
+If a blk_crypto_key is being used on multiple request_queues, then
+``blk_crypto_config_supported()`` (if used), ``blk_crypto_start_using_key()``,
+and ``blk_crypto_evict_key()`` must be called on each request_queue.
API presented to device drivers
===============================
-A :c:type:``struct blk_keyslot_manager`` should be set up by device drivers in
-the ``request_queue`` of the device. The device driver needs to call
-``blk_ksm_init`` (or its resource-managed variant ``devm_blk_ksm_init``) on the
-``blk_keyslot_manager``, while specifying the number of keyslots supported by
-the hardware.
-
-The device driver also needs to tell the KSM how to actually manipulate the
-IE hardware in the device to do things like programming the crypto key into
-the IE hardware into a particular keyslot. All this is achieved through the
-struct blk_ksm_ll_ops field in the KSM that the device driver
-must fill up after initing the ``blk_keyslot_manager``.
-
-The KSM also handles runtime power management for the device when applicable
-(e.g. when it wants to program a crypto key into the IE hardware, the device
-must be runtime powered on) - so the device driver must also set the ``dev``
-field in the ksm to point to the `struct device` for the KSM to use for runtime
-power management.
-
-``blk_ksm_reprogram_all_keys`` can be called by device drivers if the device
-needs each and every of its keyslots to be reprogrammed with the key it
-"should have" at the point in time when the function is called. This is useful
-e.g. if a device loses all its keys on runtime power down/up.
-
-If the driver used ``blk_ksm_init`` instead of ``devm_blk_ksm_init``, then
-``blk_ksm_destroy`` should be called to free up all resources used by a
-``blk_keyslot_manager`` once it is no longer needed.
+A device driver that wants to support inline encryption must set up a
+blk_crypto_profile in the request_queue of its device. To do this, it first
+must call ``blk_crypto_profile_init()`` (or its resource-managed variant
+``devm_blk_crypto_profile_init()``), providing the number of keyslots.
+
+Next, it must advertise its crypto capabilities by setting fields in the
+blk_crypto_profile, e.g. ``modes_supported`` and ``max_dun_bytes_supported``.
+
+It then must set function pointers in the ``ll_ops`` field of the
+blk_crypto_profile to tell upper layers how to control the inline encryption
+hardware, e.g. how to program and evict keyslots. Most drivers will need to
+implement ``keyslot_program`` and ``keyslot_evict``. For details, see the
+comments for ``struct blk_crypto_ll_ops``.
+
+Once the driver registers a blk_crypto_profile with a request_queue, I/O
+requests the driver receives via that queue may have an encryption context. All
+encryption contexts will be compatible with the crypto capabilities declared in
+the blk_crypto_profile, so drivers don't need to worry about handling
+unsupported requests. Also, if a nonzero number of keyslots was declared in the
+blk_crypto_profile, then all I/O requests that have an encryption context will
+also have a keyslot which was already programmed with the appropriate key.
+
+If the driver implements runtime suspend and its blk_crypto_ll_ops don't work
+while the device is runtime-suspended, then the driver must also set the ``dev``
+field of the blk_crypto_profile to point to the ``struct device`` that will be
+resumed before any of the low-level operations are called.
+
+If there are situations where the inline encryption hardware loses the contents
+of its keyslots, e.g. device resets, the driver must handle reprogramming the
+keyslots. To do this, the driver may call ``blk_crypto_reprogram_all_keys()``.
+
+Finally, if the driver used ``blk_crypto_profile_init()`` instead of
+``devm_blk_crypto_profile_init()``, then it is responsible for calling
+``blk_crypto_profile_destroy()`` when the crypto profile is no longer needed.
Layered Devices
===============
-Request queue based layered devices like dm-rq that wish to support IE need to
-create their own keyslot manager for their request queue, and expose whatever
-functionality they choose. When a layered device wants to pass a clone of that
-request to another ``request_queue``, blk-crypto will initialize and prepare the
-clone as necessary - see ``blk_crypto_insert_cloned_request`` in
-``blk-crypto.c``.
-
-
-Future Optimizations for layered devices
-========================================
-
-Creating a keyslot manager for a layered device uses up memory for each
-keyslot, and in general, a layered device merely passes the request on to a
-"child" device, so the keyslots in the layered device itself are completely
-unused, and don't need any refcounting or keyslot programming. We can instead
-define a new type of KSM; the "passthrough KSM", that layered devices can use
-to advertise an unlimited number of keyslots, and support for any encryption
-algorithms they choose, while not actually using any memory for each keyslot.
-Another use case for the "passthrough KSM" is for IE devices that do not have a
-limited number of keyslots.
-
+Request queue based layered devices like dm-rq that wish to support inline
+encryption need to create their own blk_crypto_profile for their request_queue,
+and expose whatever functionality they choose. When a layered device wants to
+pass a clone of that request to another request_queue, blk-crypto will
+initialize and prepare the clone as necessary; see
+``blk_crypto_insert_cloned_request()``.
Interaction between inline encryption and blk integrity
=======================================================
@@ -257,7 +290,7 @@ Because there isn't any real hardware yet, it seems prudent to assume that
hardware implementations might not implement both features together correctly,
and disallow the combination for now. Whenever a device supports integrity, the
kernel will pretend that the device does not support hardware inline encryption
-(by essentially setting the keyslot manager in the request_queue of the device
-to NULL). When the crypto API fallback is enabled, this means that all bios with
-and encryption context will use the fallback, and IO will complete as usual.
-When the fallback is disabled, a bio with an encryption context will be failed.
+(by setting the blk_crypto_profile in the request_queue of the device to NULL).
+When the crypto API fallback is enabled, this means that all bios with and
+encryption context will use the fallback, and IO will complete as usual. When
+the fallback is disabled, a bio with an encryption context will be failed.
--
2.33.0
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