[PATCH v2 5/9] pcrypt: remove padata cpumask notifier

From: Daniel Jordan
Date: Thu Aug 29 2019 - 13:37:56 EST


Now that padata_do_parallel takes care of finding an alternate callback
CPU, there's no need for pcrypt's callback cpumask, so remove it and the
notifier callback that keeps it in sync.

Signed-off-by: Daniel Jordan <daniel.m.jordan@xxxxxxxxxx>
Acked-by: Steffen Klassert <steffen.klassert@xxxxxxxxxxx>
Cc: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Cc: Lai Jiangshan <jiangshanlai@xxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Tejun Heo <tj@xxxxxxxxxx>
Cc: linux-crypto@xxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
---
crypto/pcrypt.c | 125 +++++++-----------------------------------------
1 file changed, 18 insertions(+), 107 deletions(-)

diff --git a/crypto/pcrypt.c b/crypto/pcrypt.c
index efca962ab12a..2ec36e6a132f 100644
--- a/crypto/pcrypt.c
+++ b/crypto/pcrypt.c
@@ -18,33 +18,8 @@
#include <linux/cpu.h>
#include <crypto/pcrypt.h>

-struct padata_pcrypt {
- struct padata_instance *pinst;
-
- /*
- * Cpumask for callback CPUs. It should be
- * equal to serial cpumask of corresponding padata instance,
- * so it is updated when padata notifies us about serial
- * cpumask change.
- *
- * cb_cpumask is protected by RCU. This fact prevents us from
- * using cpumask_var_t directly because the actual type of
- * cpumsak_var_t depends on kernel configuration(particularly on
- * CONFIG_CPUMASK_OFFSTACK macro). Depending on the configuration
- * cpumask_var_t may be either a pointer to the struct cpumask
- * or a variable allocated on the stack. Thus we can not safely use
- * cpumask_var_t with RCU operations such as rcu_assign_pointer or
- * rcu_dereference. So cpumask_var_t is wrapped with struct
- * pcrypt_cpumask which makes possible to use it with RCU.
- */
- struct pcrypt_cpumask {
- cpumask_var_t mask;
- } *cb_cpumask;
- struct notifier_block nblock;
-};
-
-static struct padata_pcrypt pencrypt;
-static struct padata_pcrypt pdecrypt;
+static struct padata_instance *pencrypt;
+static struct padata_instance *pdecrypt;
static struct kset *pcrypt_kset;

struct pcrypt_instance_ctx {
@@ -128,7 +103,7 @@ static int pcrypt_aead_encrypt(struct aead_request *req)
req->cryptlen, req->iv);
aead_request_set_ad(creq, req->assoclen);

- err = padata_do_parallel(pencrypt.pinst, padata, &ctx->cb_cpu);
+ err = padata_do_parallel(pencrypt, padata, &ctx->cb_cpu);
if (!err)
return -EINPROGRESS;

@@ -170,7 +145,7 @@ static int pcrypt_aead_decrypt(struct aead_request *req)
req->cryptlen, req->iv);
aead_request_set_ad(creq, req->assoclen);

- err = padata_do_parallel(pdecrypt.pinst, padata, &ctx->cb_cpu);
+ err = padata_do_parallel(pdecrypt, padata, &ctx->cb_cpu);
if (!err)
return -EINPROGRESS;

@@ -317,36 +292,6 @@ static int pcrypt_create(struct crypto_template *tmpl, struct rtattr **tb)
return -EINVAL;
}

-static int pcrypt_cpumask_change_notify(struct notifier_block *self,
- unsigned long val, void *data)
-{
- struct padata_pcrypt *pcrypt;
- struct pcrypt_cpumask *new_mask, *old_mask;
- struct padata_cpumask *cpumask = (struct padata_cpumask *)data;
-
- if (!(val & PADATA_CPU_SERIAL))
- return 0;
-
- pcrypt = container_of(self, struct padata_pcrypt, nblock);
- new_mask = kmalloc(sizeof(*new_mask), GFP_KERNEL);
- if (!new_mask)
- return -ENOMEM;
- if (!alloc_cpumask_var(&new_mask->mask, GFP_KERNEL)) {
- kfree(new_mask);
- return -ENOMEM;
- }
-
- old_mask = pcrypt->cb_cpumask;
-
- cpumask_copy(new_mask->mask, cpumask->cbcpu);
- rcu_assign_pointer(pcrypt->cb_cpumask, new_mask);
- synchronize_rcu();
-
- free_cpumask_var(old_mask->mask);
- kfree(old_mask);
- return 0;
-}
-
static int pcrypt_sysfs_add(struct padata_instance *pinst, const char *name)
{
int ret;
@@ -359,63 +304,29 @@ static int pcrypt_sysfs_add(struct padata_instance *pinst, const char *name)
return ret;
}

-static int pcrypt_init_padata(struct padata_pcrypt *pcrypt,
- const char *name)
+static int pcrypt_init_padata(struct padata_instance **pinst, const char *name)
{
int ret = -ENOMEM;
- struct pcrypt_cpumask *mask;

get_online_cpus();

- pcrypt->pinst = padata_alloc_possible(name);
- if (!pcrypt->pinst)
- goto err;
-
- mask = kmalloc(sizeof(*mask), GFP_KERNEL);
- if (!mask)
- goto err_free_padata;
- if (!alloc_cpumask_var(&mask->mask, GFP_KERNEL)) {
- kfree(mask);
- goto err_free_padata;
- }
-
- cpumask_and(mask->mask, cpu_possible_mask, cpu_online_mask);
- rcu_assign_pointer(pcrypt->cb_cpumask, mask);
-
- pcrypt->nblock.notifier_call = pcrypt_cpumask_change_notify;
- ret = padata_register_cpumask_notifier(pcrypt->pinst, &pcrypt->nblock);
- if (ret)
- goto err_free_cpumask;
+ *pinst = padata_alloc_possible(name);
+ if (!*pinst)
+ return ret;

- ret = pcrypt_sysfs_add(pcrypt->pinst, name);
+ ret = pcrypt_sysfs_add(*pinst, name);
if (ret)
- goto err_unregister_notifier;
+ padata_free(*pinst);

put_online_cpus();

- return ret;
-
-err_unregister_notifier:
- padata_unregister_cpumask_notifier(pcrypt->pinst, &pcrypt->nblock);
-err_free_cpumask:
- free_cpumask_var(mask->mask);
- kfree(mask);
-err_free_padata:
- padata_free(pcrypt->pinst);
-err:
- put_online_cpus();
-
return ret;
}

-static void pcrypt_fini_padata(struct padata_pcrypt *pcrypt)
+static void pcrypt_fini_padata(struct padata_instance *pinst)
{
- free_cpumask_var(pcrypt->cb_cpumask->mask);
- kfree(pcrypt->cb_cpumask);
-
- padata_stop(pcrypt->pinst);
- padata_unregister_cpumask_notifier(pcrypt->pinst, &pcrypt->nblock);
- padata_free(pcrypt->pinst);
+ padata_stop(pinst);
+ padata_free(pinst);
}

static struct crypto_template pcrypt_tmpl = {
@@ -440,13 +351,13 @@ static int __init pcrypt_init(void)
if (err)
goto err_deinit_pencrypt;

- padata_start(pencrypt.pinst);
- padata_start(pdecrypt.pinst);
+ padata_start(pencrypt);
+ padata_start(pdecrypt);

return crypto_register_template(&pcrypt_tmpl);

err_deinit_pencrypt:
- pcrypt_fini_padata(&pencrypt);
+ pcrypt_fini_padata(pencrypt);
err_unreg_kset:
kset_unregister(pcrypt_kset);
err:
@@ -455,8 +366,8 @@ static int __init pcrypt_init(void)

static void __exit pcrypt_exit(void)
{
- pcrypt_fini_padata(&pencrypt);
- pcrypt_fini_padata(&pdecrypt);
+ pcrypt_fini_padata(pencrypt);
+ pcrypt_fini_padata(pdecrypt);

kset_unregister(pcrypt_kset);
crypto_unregister_template(&pcrypt_tmpl);
--
2.23.0