1 files changed, 196 insertions, 58 deletions

diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c
index 9a896e1cb2ea..50ae6ef83738 100644
--- a/drivers/md/dm-crypt.c
+++ b/drivers/md/dm-crypt.c
@@ -18,6 +18,7 @@
 #include <linux/crypto.h>
 #include <linux/workqueue.h>
 #include <linux/backing-dev.h>
+#include <linux/percpu.h>
 #include <asm/atomic.h>
 #include <linux/scatterlist.h>
 #include <asm/page.h>
@@ -77,7 +78,6 @@ struct crypt_iv_operations {
 };
 
 struct iv_essiv_private {
-        struct crypto_cipher *tfm;
         struct crypto_hash *hash_tfm;
         u8 *salt;
 };
@@ -91,6 +91,22 @@ struct iv_benbi_private {
  * and encrypts / decrypts at the same time.
  */
 enum flags { DM_CRYPT_SUSPENDED, DM_CRYPT_KEY_VALID };
+
+/*
+ * Duplicated per-CPU state for cipher.
+ */
+struct crypt_cpu {
+        struct ablkcipher_request *req;
+        struct crypto_ablkcipher *tfm;
+
+        /* ESSIV: struct crypto_cipher *essiv_tfm */
+        void *iv_private;
+};
+
+/*
+ * The fields in here must be read only after initialization,
+ * changing state should be in crypt_cpu.
+ */
 struct crypt_config {
         struct dm_dev *dev;
         sector_t start;
@@ -119,6 +135,12 @@ struct crypt_config {
         unsigned int iv_size;
 
         /*
+         * Duplicated per cpu state. Access through
+         * per_cpu_ptr() only.
+         */
+        struct crypt_cpu __percpu *cpu;
+
+        /*
          * Layout of each crypto request:
          *
          *   struct ablkcipher_request
@@ -132,9 +154,7 @@ struct crypt_config {
          * correctly aligned.
          */
         unsigned int dmreq_start;
-        struct ablkcipher_request *req;
 
-        struct crypto_ablkcipher *tfm;
         unsigned long flags;
         unsigned int key_size;
         u8 key[0];
@@ -149,6 +169,19 @@ static struct kmem_cache *_crypt_io_pool;
 static void clone_init(struct dm_crypt_io *, struct bio *);
 static void kcryptd_queue_crypt(struct dm_crypt_io *io);
 
+static struct crypt_cpu *this_crypt_config(struct crypt_config *cc)
+{
+        return this_cpu_ptr(cc->cpu);
+}
+
+/*
+ * Use this to access cipher attributes that are the same for each CPU.
+ */
+static struct crypto_ablkcipher *any_tfm(struct crypt_config *cc)
+{
+        return __this_cpu_ptr(cc->cpu)->tfm;
+}
+
 /*
  * Different IV generation algorithms:
  *
@@ -195,7 +228,8 @@ static int crypt_iv_essiv_init(struct crypt_config *cc)
         struct iv_essiv_private *essiv = &cc->iv_gen_private.essiv;
         struct hash_desc desc;
         struct scatterlist sg;
-        int err;
+        struct crypto_cipher *essiv_tfm;
+        int err, cpu;
 
         sg_init_one(&sg, cc->key, cc->key_size);
         desc.tfm = essiv->hash_tfm;
@@ -205,8 +239,16 @@ static int crypt_iv_essiv_init(struct crypt_config *cc)
         if (err)
                 return err;
 
-        return crypto_cipher_setkey(essiv->tfm, essiv->salt,
+        for_each_possible_cpu(cpu) {
+                essiv_tfm = per_cpu_ptr(cc->cpu, cpu)->iv_private,
+
+                err = crypto_cipher_setkey(essiv_tfm, essiv->salt,
                                     crypto_hash_digestsize(essiv->hash_tfm));
+                if (err)
+                        return err;
+        }
+
+        return 0;
 }
 
 /* Wipe salt and reset key derived from volume key */
@@ -214,24 +256,76 @@ static int crypt_iv_essiv_wipe(struct crypt_config *cc)
 {
         struct iv_essiv_private *essiv = &cc->iv_gen_private.essiv;
         unsigned salt_size = crypto_hash_digestsize(essiv->hash_tfm);
+        struct crypto_cipher *essiv_tfm;
+        int cpu, r, err = 0;
 
         memset(essiv->salt, 0, salt_size);
 
-        return crypto_cipher_setkey(essiv->tfm, essiv->salt, salt_size);
+        for_each_possible_cpu(cpu) {
+                essiv_tfm = per_cpu_ptr(cc->cpu, cpu)->iv_private;
+                r = crypto_cipher_setkey(essiv_tfm, essiv->salt, salt_size);
+                if (r)
+                        err = r;
+        }
+
+        return err;
+}
+
+/* Set up per cpu cipher state */
+static struct crypto_cipher *setup_essiv_cpu(struct crypt_config *cc,
+                                             struct dm_target *ti,
+                                             u8 *salt, unsigned saltsize)
+{
+        struct crypto_cipher *essiv_tfm;
+        int err;
+
+        /* Setup the essiv_tfm with the given salt */
+        essiv_tfm = crypto_alloc_cipher(cc->cipher, 0, CRYPTO_ALG_ASYNC);
+        if (IS_ERR(essiv_tfm)) {
+                ti->error = "Error allocating crypto tfm for ESSIV";
+                return essiv_tfm;
+        }
+
+        if (crypto_cipher_blocksize(essiv_tfm) !=
+            crypto_ablkcipher_ivsize(any_tfm(cc))) {
+                ti->error = "Block size of ESSIV cipher does "
+                            "not match IV size of block cipher";
+                crypto_free_cipher(essiv_tfm);
+                return ERR_PTR(-EINVAL);
+        }
+
+        err = crypto_cipher_setkey(essiv_tfm, salt, saltsize);
+        if (err) {
+                ti->error = "Failed to set key for ESSIV cipher";
+                crypto_free_cipher(essiv_tfm);
+                return ERR_PTR(err);
+        }
+
+        return essiv_tfm;
 }
 
 static void crypt_iv_essiv_dtr(struct crypt_config *cc)
 {
+        int cpu;
+        struct crypt_cpu *cpu_cc;
+        struct crypto_cipher *essiv_tfm;
         struct iv_essiv_private *essiv = &cc->iv_gen_private.essiv;
 
-        crypto_free_cipher(essiv->tfm);
-        essiv->tfm = NULL;
-
         crypto_free_hash(essiv->hash_tfm);
         essiv->hash_tfm = NULL;
 
         kzfree(essiv->salt);
         essiv->salt = NULL;
+
+        for_each_possible_cpu(cpu) {
+                cpu_cc = per_cpu_ptr(cc->cpu, cpu);
+                essiv_tfm = cpu_cc->iv_private;
+
+                if (essiv_tfm)
+                        crypto_free_cipher(essiv_tfm);
+
+                cpu_cc->iv_private = NULL;
+        }
 }
 
 static int crypt_iv_essiv_ctr(struct crypt_config *cc, struct dm_target *ti,
@@ -240,7 +334,7 @@ static int crypt_iv_essiv_ctr(struct crypt_config *cc, struct dm_target *ti,
         struct crypto_cipher *essiv_tfm = NULL;
         struct crypto_hash *hash_tfm = NULL;
         u8 *salt = NULL;
-        int err;
+        int err, cpu;
 
         if (!opts) {
                 ti->error = "Digest algorithm missing for ESSIV mode";
@@ -262,30 +356,22 @@ static int crypt_iv_essiv_ctr(struct crypt_config *cc, struct dm_target *ti,
                 goto bad;
         }
 
-        /* Allocate essiv_tfm */
-        essiv_tfm = crypto_alloc_cipher(cc->cipher, 0, CRYPTO_ALG_ASYNC);
-        if (IS_ERR(essiv_tfm)) {
-                ti->error = "Error allocating crypto tfm for ESSIV";
-                err = PTR_ERR(essiv_tfm);
-                goto bad;
-        }
-        if (crypto_cipher_blocksize(essiv_tfm) !=
-            crypto_ablkcipher_ivsize(cc->tfm)) {
-                ti->error = "Block size of ESSIV cipher does "
-                            "not match IV size of block cipher";
-                err = -EINVAL;
-                goto bad;
-        }
-
         cc->iv_gen_private.essiv.salt = salt;
-        cc->iv_gen_private.essiv.tfm = essiv_tfm;
         cc->iv_gen_private.essiv.hash_tfm = hash_tfm;
 
+        for_each_possible_cpu(cpu) {
+                essiv_tfm = setup_essiv_cpu(cc, ti, salt,
+                                        crypto_hash_digestsize(hash_tfm));
+                if (IS_ERR(essiv_tfm)) {
+                        crypt_iv_essiv_dtr(cc);
+                        return PTR_ERR(essiv_tfm);
+                }
+                per_cpu_ptr(cc->cpu, cpu)->iv_private = essiv_tfm;
+        }
+
         return 0;
 
 bad:
-        if (essiv_tfm && !IS_ERR(essiv_tfm))
-                crypto_free_cipher(essiv_tfm);
         if (hash_tfm && !IS_ERR(hash_tfm))
                 crypto_free_hash(hash_tfm);
         kfree(salt);
@@ -294,16 +380,19 @@ bad:
 
 static int crypt_iv_essiv_gen(struct crypt_config *cc, u8 *iv, sector_t sector)
 {
+        struct crypto_cipher *essiv_tfm = this_crypt_config(cc)->iv_private;
+
         memset(iv, 0, cc->iv_size);
         *(u64 *)iv = cpu_to_le64(sector);
-        crypto_cipher_encrypt_one(cc->iv_gen_private.essiv.tfm, iv, iv);
+        crypto_cipher_encrypt_one(essiv_tfm, iv, iv);
+
         return 0;
 }
 
 static int crypt_iv_benbi_ctr(struct crypt_config *cc, struct dm_target *ti,
                               const char *opts)
 {
-        unsigned bs = crypto_ablkcipher_blocksize(cc->tfm);
+        unsigned bs = crypto_ablkcipher_blocksize(any_tfm(cc));
         int log = ilog2(bs);
 
         /* we need to calculate how far we must shift the sector count
@@ -412,7 +501,7 @@ static int crypt_convert_block(struct crypt_config *cc,
 
         dmreq = dmreq_of_req(cc, req);
         iv = (u8 *)ALIGN((unsigned long)(dmreq + 1),
-                         crypto_ablkcipher_alignmask(cc->tfm) + 1);
+                         crypto_ablkcipher_alignmask(any_tfm(cc)) + 1);
 
         dmreq->ctx = ctx;
         sg_init_table(&dmreq->sg_in, 1);
@@ -454,16 +543,19 @@ static int crypt_convert_block(struct crypt_config *cc,
 
 static void kcryptd_async_done(struct crypto_async_request *async_req,
                                int error);
+
 static void crypt_alloc_req(struct crypt_config *cc,
                             struct convert_context *ctx)
 {
-        if (!cc->req)
-                cc->req = mempool_alloc(cc->req_pool, GFP_NOIO);
-        ablkcipher_request_set_tfm(cc->req, cc->tfm);
-        ablkcipher_request_set_callback(cc->req, CRYPTO_TFM_REQ_MAY_BACKLOG |
-                                        CRYPTO_TFM_REQ_MAY_SLEEP,
-                                        kcryptd_async_done,
-                                        dmreq_of_req(cc, cc->req));
+        struct crypt_cpu *this_cc = this_crypt_config(cc);
+
+        if (!this_cc->req)
+                this_cc->req = mempool_alloc(cc->req_pool, GFP_NOIO);
+
+        ablkcipher_request_set_tfm(this_cc->req, this_cc->tfm);
+        ablkcipher_request_set_callback(this_cc->req,
+            CRYPTO_TFM_REQ_MAY_BACKLOG | CRYPTO_TFM_REQ_MAY_SLEEP,
+            kcryptd_async_done, dmreq_of_req(cc, this_cc->req));
 }
 
 /*
@@ -472,6 +564,7 @@ static void crypt_alloc_req(struct crypt_config *cc,
 static int crypt_convert(struct crypt_config *cc,
                          struct convert_context *ctx)
 {
+        struct crypt_cpu *this_cc = this_crypt_config(cc);
         int r;
 
         atomic_set(&ctx->pending, 1);
@@ -483,7 +576,7 @@ static int crypt_convert(struct crypt_config *cc,
 
                 atomic_inc(&ctx->pending);
 
-                r = crypt_convert_block(cc, ctx, cc->req);
+                r = crypt_convert_block(cc, ctx, this_cc->req);
 
                 switch (r) {
                 /* async */
@@ -492,7 +585,7 @@ static int crypt_convert(struct crypt_config *cc,
                         INIT_COMPLETION(ctx->restart);
                         /* fall through*/
                 case -EINPROGRESS:
-                        cc->req = NULL;
+                        this_cc->req = NULL;
                         ctx->sector++;
                         continue;
 
@@ -651,6 +744,9 @@ static void crypt_dec_pending(struct dm_crypt_io *io)
  * They must be separated as otherwise the final stages could be
  * starved by new requests which can block in the first stages due
  * to memory allocation.
+ *
+ * The work is done per CPU global for all dm-crypt instances.
+ * They should not depend on each other and do not block.
  */
 static void crypt_endio(struct bio *clone, int error)
 {
@@ -971,6 +1067,20 @@ static void crypt_encode_key(char *hex, u8 *key, unsigned int size)
         }
 }
 
+static int crypt_setkey_allcpus(struct crypt_config *cc)
+{
+        int cpu, err = 0, r;
+
+        for_each_possible_cpu(cpu) {
+                r = crypto_ablkcipher_setkey(per_cpu_ptr(cc->cpu, cpu)->tfm,
+                                               cc->key, cc->key_size);
+                if (r)
+                        err = r;
+        }
+
+        return err;
+}
+
 static int crypt_set_key(struct crypt_config *cc, char *key)
 {
         /* The key size may not be changed. */
@@ -986,19 +1096,22 @@ static int crypt_set_key(struct crypt_config *cc, char *key)
 
         set_bit(DM_CRYPT_KEY_VALID, &cc->flags);
 
-        return crypto_ablkcipher_setkey(cc->tfm, cc->key, cc->key_size);
+        return crypt_setkey_allcpus(cc);
 }
 
 static int crypt_wipe_key(struct crypt_config *cc)
 {
         clear_bit(DM_CRYPT_KEY_VALID, &cc->flags);
         memset(&cc->key, 0, cc->key_size * sizeof(u8));
-        return crypto_ablkcipher_setkey(cc->tfm, cc->key, cc->key_size);
+
+        return crypt_setkey_allcpus(cc);
 }
 
 static void crypt_dtr(struct dm_target *ti)
 {
         struct crypt_config *cc = ti->private;
+        struct crypt_cpu *cpu_cc;
+        int cpu;
 
         ti->private = NULL;
 
@@ -1010,6 +1123,15 @@ static void crypt_dtr(struct dm_target *ti)
         if (cc->crypt_queue)
                 destroy_workqueue(cc->crypt_queue);
 
+        if (cc->cpu)
+                for_each_possible_cpu(cpu) {
+                        cpu_cc = per_cpu_ptr(cc->cpu, cpu);
+                        if (cpu_cc->req)
+                                mempool_free(cpu_cc->req, cc->req_pool);
+                        if (cpu_cc->tfm)
+                                crypto_free_ablkcipher(cpu_cc->tfm);
+                }
+
         if (cc->bs)
                 bioset_free(cc->bs);
 
@@ -1023,12 +1145,12 @@ static void crypt_dtr(struct dm_target *ti)
         if (cc->iv_gen_ops && cc->iv_gen_ops->dtr)
                 cc->iv_gen_ops->dtr(cc);
 
-        if (cc->tfm && !IS_ERR(cc->tfm))
-                crypto_free_ablkcipher(cc->tfm);
-
         if (cc->dev)
                 dm_put_device(ti, cc->dev);
 
+        if (cc->cpu)
+                free_percpu(cc->cpu);
+
         kzfree(cc->cipher);
         kzfree(cc->cipher_string);
 
@@ -1040,9 +1162,10 @@ static int crypt_ctr_cipher(struct dm_target *ti,
                             char *cipher_in, char *key)
 {
         struct crypt_config *cc = ti->private;
+        struct crypto_ablkcipher *tfm;
         char *tmp, *cipher, *chainmode, *ivmode, *ivopts;
         char *cipher_api = NULL;
-        int ret = -EINVAL;
+        int cpu, ret = -EINVAL;
 
         /* Convert to crypto api definition? */
         if (strchr(cipher_in, '(')) {
@@ -1072,6 +1195,12 @@ static int crypt_ctr_cipher(struct dm_target *ti,
         if (tmp)
                 DMWARN("Ignoring unexpected additional cipher options");
 
+        cc->cpu = alloc_percpu(struct crypt_cpu);
+        if (!cc->cpu) {
+                ti->error = "Cannot allocate per cpu state";
+                goto bad_mem;
+        }
+
         /*
          * For compatibility with the original dm-crypt mapping format, if
          * only the cipher name is supplied, use cbc-plain.
@@ -1098,11 +1227,14 @@ static int crypt_ctr_cipher(struct dm_target *ti,
         }
 
         /* Allocate cipher */
-        cc->tfm = crypto_alloc_ablkcipher(cipher_api, 0, 0);
-        if (IS_ERR(cc->tfm)) {
-                ret = PTR_ERR(cc->tfm);
-                ti->error = "Error allocating crypto tfm";
-                goto bad;
+        for_each_possible_cpu(cpu) {
+                tfm = crypto_alloc_ablkcipher(cipher_api, 0, 0);
+                if (IS_ERR(tfm)) {
+                        ret = PTR_ERR(tfm);
+                        ti->error = "Error allocating crypto tfm";
+                        goto bad;
+                }
+                per_cpu_ptr(cc->cpu, cpu)->tfm = tfm;
         }
 
         /* Initialize and set key */
@@ -1113,7 +1245,7 @@ static int crypt_ctr_cipher(struct dm_target *ti,
         }
 
         /* Initialize IV */
-        cc->iv_size = crypto_ablkcipher_ivsize(cc->tfm);
+        cc->iv_size = crypto_ablkcipher_ivsize(any_tfm(cc));
         if (cc->iv_size)
                 /* at least a 64 bit sector number should fit in our buffer */
                 cc->iv_size = max(cc->iv_size,
@@ -1208,9 +1340,9 @@ static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv)
         }
 
         cc->dmreq_start = sizeof(struct ablkcipher_request);
-        cc->dmreq_start += crypto_ablkcipher_reqsize(cc->tfm);
+        cc->dmreq_start += crypto_ablkcipher_reqsize(any_tfm(cc));
         cc->dmreq_start = ALIGN(cc->dmreq_start, crypto_tfm_ctx_alignment());
-        cc->dmreq_start += crypto_ablkcipher_alignmask(cc->tfm) &
+        cc->dmreq_start += crypto_ablkcipher_alignmask(any_tfm(cc)) &
                            ~(crypto_tfm_ctx_alignment() - 1);
 
         cc->req_pool = mempool_create_kmalloc_pool(MIN_IOS, cc->dmreq_start +
@@ -1219,7 +1351,6 @@ static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv)
                 ti->error = "Cannot allocate crypt request mempool";
                 goto bad;
         }
-        cc->req = NULL;
 
         cc->page_pool = mempool_create_page_pool(MIN_POOL_PAGES, 0);
         if (!cc->page_pool) {
@@ -1252,13 +1383,20 @@ static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv)
         cc->start = tmpll;
 
         ret = -ENOMEM;
-        cc->io_queue = create_singlethread_workqueue("kcryptd_io");
+        cc->io_queue = alloc_workqueue("kcryptd_io",
+                                       WQ_NON_REENTRANT|
+                                       WQ_MEM_RECLAIM,
+                                       1);
         if (!cc->io_queue) {
                 ti->error = "Couldn't create kcryptd io queue";
                 goto bad;
         }
 
-        cc->crypt_queue = create_singlethread_workqueue("kcryptd");
+        cc->crypt_queue = alloc_workqueue("kcryptd",
+                                          WQ_NON_REENTRANT|
+                                          WQ_CPU_INTENSIVE|
+                                          WQ_MEM_RECLAIM,
+                                          1);
         if (!cc->crypt_queue) {
                 ti->error = "Couldn't create kcryptd queue";
                 goto bad;
@@ -1418,7 +1556,7 @@ static int crypt_iterate_devices(struct dm_target *ti,
 
 static struct target_type crypt_target = {
         .name   = "crypt",
-        .version = {1, 8, 0},
+        .version = {1, 9, 0},
         .module = THIS_MODULE,
         .ctr    = crypt_ctr,
         .dtr    = crypt_dtr,