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authorLinus Torvalds <torvalds@linux-foundation.org>2022-03-21 16:02:36 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2022-03-21 16:02:36 -0700
commit93e220a62da36f766b3188e76e234607e41488f9 (patch)
treed56d5609e4b290baa9b46a48b123ab9c4f23f073 /drivers/char/hw_random
parent5628b8de1228436d47491c662dc521bc138a3d43 (diff)
parent0e03b8fd29363f2df44e2a7a176d486de550757a (diff)
Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto updates from Herbert Xu: "API: - hwrng core now credits for low-quality RNG devices. Algorithms: - Optimisations for neon aes on arm/arm64. - Add accelerated crc32_be on arm64. - Add ffdheXYZ(dh) templates. - Disallow hmac keys < 112 bits in FIPS mode. - Add AVX assembly implementation for sm3 on x86. Drivers: - Add missing local_bh_disable calls for crypto_engine callback. - Ensure BH is disabled in crypto_engine callback path. - Fix zero length DMA mappings in ccree. - Add synchronization between mailbox accesses in octeontx2. - Add Xilinx SHA3 driver. - Add support for the TDES IP available on sama7g5 SoC in atmel" * 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (137 commits) crypto: xilinx - Turn SHA into a tristate and allow COMPILE_TEST MAINTAINERS: update HPRE/SEC2/TRNG driver maintainers list crypto: dh - Remove the unused function dh_safe_prime_dh_alg() hwrng: nomadik - Change clk_disable to clk_disable_unprepare crypto: arm64 - cleanup comments crypto: qat - fix initialization of pfvf rts_map_msg structures crypto: qat - fix initialization of pfvf cap_msg structures crypto: qat - remove unneeded assignment crypto: qat - disable registration of algorithms crypto: hisilicon/qm - fix memset during queues clearing crypto: xilinx: prevent probing on non-xilinx hardware crypto: marvell/octeontx - Use swap() instead of open coding it crypto: ccree - Fix use after free in cc_cipher_exit() crypto: ccp - ccp_dmaengine_unregister release dma channels crypto: octeontx2 - fix missing unlock hwrng: cavium - fix NULL but dereferenced coccicheck error crypto: cavium/nitrox - don't cast parameter in bit operations crypto: vmx - add missing dependencies MAINTAINERS: Add maintainer for Xilinx ZynqMP SHA3 driver crypto: xilinx - Add Xilinx SHA3 driver ...
Diffstat (limited to 'drivers/char/hw_random')
-rw-r--r--drivers/char/hw_random/Kconfig2
-rw-r--r--drivers/char/hw_random/atmel-rng.c148
-rw-r--r--drivers/char/hw_random/cavium-rng-vf.c2
-rw-r--r--drivers/char/hw_random/core.c161
-rw-r--r--drivers/char/hw_random/nomadik-rng.c4
5 files changed, 216 insertions, 101 deletions
diff --git a/drivers/char/hw_random/Kconfig b/drivers/char/hw_random/Kconfig
index 9704963f9d50..a087156a5818 100644
--- a/drivers/char/hw_random/Kconfig
+++ b/drivers/char/hw_random/Kconfig
@@ -401,7 +401,7 @@ config HW_RANDOM_MESON
config HW_RANDOM_CAVIUM
tristate "Cavium ThunderX Random Number Generator support"
- depends on HW_RANDOM && PCI && ARM64
+ depends on HW_RANDOM && PCI && ARCH_THUNDER
default HW_RANDOM
help
This driver provides kernel-side support for the Random Number
diff --git a/drivers/char/hw_random/atmel-rng.c b/drivers/char/hw_random/atmel-rng.c
index ecb71c4317a5..b8effe77d80f 100644
--- a/drivers/char/hw_random/atmel-rng.c
+++ b/drivers/char/hw_random/atmel-rng.c
@@ -13,13 +13,16 @@
#include <linux/err.h>
#include <linux/clk.h>
#include <linux/io.h>
+#include <linux/iopoll.h>
#include <linux/hw_random.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
#define TRNG_CR 0x00
#define TRNG_MR 0x04
#define TRNG_ISR 0x1c
+#define TRNG_ISR_DATRDY BIT(0)
#define TRNG_ODATA 0x50
#define TRNG_KEY 0x524e4700 /* RNG */
@@ -34,37 +37,79 @@ struct atmel_trng {
struct clk *clk;
void __iomem *base;
struct hwrng rng;
+ bool has_half_rate;
};
+static bool atmel_trng_wait_ready(struct atmel_trng *trng, bool wait)
+{
+ int ready;
+
+ ready = readl(trng->base + TRNG_ISR) & TRNG_ISR_DATRDY;
+ if (!ready && wait)
+ readl_poll_timeout(trng->base + TRNG_ISR, ready,
+ ready & TRNG_ISR_DATRDY, 1000, 20000);
+
+ return !!ready;
+}
+
static int atmel_trng_read(struct hwrng *rng, void *buf, size_t max,
bool wait)
{
struct atmel_trng *trng = container_of(rng, struct atmel_trng, rng);
u32 *data = buf;
+ int ret;
- /* data ready? */
- if (readl(trng->base + TRNG_ISR) & 1) {
- *data = readl(trng->base + TRNG_ODATA);
- /*
- ensure data ready is only set again AFTER the next data
- word is ready in case it got set between checking ISR
- and reading ODATA, so we don't risk re-reading the
- same word
- */
- readl(trng->base + TRNG_ISR);
- return 4;
- } else
- return 0;
+ ret = pm_runtime_get_sync((struct device *)trng->rng.priv);
+ if (ret < 0) {
+ pm_runtime_put_sync((struct device *)trng->rng.priv);
+ return ret;
+ }
+
+ ret = atmel_trng_wait_ready(trng, wait);
+ if (!ret)
+ goto out;
+
+ *data = readl(trng->base + TRNG_ODATA);
+ /*
+ * ensure data ready is only set again AFTER the next data word is ready
+ * in case it got set between checking ISR and reading ODATA, so we
+ * don't risk re-reading the same word
+ */
+ readl(trng->base + TRNG_ISR);
+ ret = 4;
+
+out:
+ pm_runtime_mark_last_busy((struct device *)trng->rng.priv);
+ pm_runtime_put_sync_autosuspend((struct device *)trng->rng.priv);
+ return ret;
}
-static void atmel_trng_enable(struct atmel_trng *trng)
+static int atmel_trng_init(struct atmel_trng *trng)
{
+ unsigned long rate;
+ int ret;
+
+ ret = clk_prepare_enable(trng->clk);
+ if (ret)
+ return ret;
+
+ if (trng->has_half_rate) {
+ rate = clk_get_rate(trng->clk);
+
+ /* if peripheral clk is above 100MHz, set HALFR */
+ if (rate > 100000000)
+ writel(TRNG_HALFR, trng->base + TRNG_MR);
+ }
+
writel(TRNG_KEY | 1, trng->base + TRNG_CR);
+
+ return 0;
}
-static void atmel_trng_disable(struct atmel_trng *trng)
+static void atmel_trng_cleanup(struct atmel_trng *trng)
{
writel(TRNG_KEY, trng->base + TRNG_CR);
+ clk_disable_unprepare(trng->clk);
}
static int atmel_trng_probe(struct platform_device *pdev)
@@ -88,32 +133,31 @@ static int atmel_trng_probe(struct platform_device *pdev)
if (!data)
return -ENODEV;
- if (data->has_half_rate) {
- unsigned long rate = clk_get_rate(trng->clk);
-
- /* if peripheral clk is above 100MHz, set HALFR */
- if (rate > 100000000)
- writel(TRNG_HALFR, trng->base + TRNG_MR);
- }
-
- ret = clk_prepare_enable(trng->clk);
- if (ret)
- return ret;
-
- atmel_trng_enable(trng);
+ trng->has_half_rate = data->has_half_rate;
trng->rng.name = pdev->name;
trng->rng.read = atmel_trng_read;
+ trng->rng.priv = (unsigned long)&pdev->dev;
+ platform_set_drvdata(pdev, trng);
- ret = devm_hwrng_register(&pdev->dev, &trng->rng);
+#ifndef CONFIG_PM
+ ret = atmel_trng_init(trng);
if (ret)
- goto err_register;
+ return ret;
+#endif
- platform_set_drvdata(pdev, trng);
+ pm_runtime_set_autosuspend_delay(&pdev->dev, 100);
+ pm_runtime_use_autosuspend(&pdev->dev);
+ pm_runtime_enable(&pdev->dev);
- return 0;
+ ret = devm_hwrng_register(&pdev->dev, &trng->rng);
+ if (ret) {
+ pm_runtime_disable(&pdev->dev);
+ pm_runtime_set_suspended(&pdev->dev);
+#ifndef CONFIG_PM
+ atmel_trng_cleanup(trng);
+#endif
+ }
-err_register:
- clk_disable_unprepare(trng->clk);
return ret;
}
@@ -121,43 +165,35 @@ static int atmel_trng_remove(struct platform_device *pdev)
{
struct atmel_trng *trng = platform_get_drvdata(pdev);
-
- atmel_trng_disable(trng);
- clk_disable_unprepare(trng->clk);
+ atmel_trng_cleanup(trng);
+ pm_runtime_disable(&pdev->dev);
+ pm_runtime_set_suspended(&pdev->dev);
return 0;
}
-#ifdef CONFIG_PM
-static int atmel_trng_suspend(struct device *dev)
+static int __maybe_unused atmel_trng_runtime_suspend(struct device *dev)
{
struct atmel_trng *trng = dev_get_drvdata(dev);
- atmel_trng_disable(trng);
- clk_disable_unprepare(trng->clk);
+ atmel_trng_cleanup(trng);
return 0;
}
-static int atmel_trng_resume(struct device *dev)
+static int __maybe_unused atmel_trng_runtime_resume(struct device *dev)
{
struct atmel_trng *trng = dev_get_drvdata(dev);
- int ret;
- ret = clk_prepare_enable(trng->clk);
- if (ret)
- return ret;
-
- atmel_trng_enable(trng);
-
- return 0;
+ return atmel_trng_init(trng);
}
-static const struct dev_pm_ops atmel_trng_pm_ops = {
- .suspend = atmel_trng_suspend,
- .resume = atmel_trng_resume,
+static const struct dev_pm_ops __maybe_unused atmel_trng_pm_ops = {
+ SET_RUNTIME_PM_OPS(atmel_trng_runtime_suspend,
+ atmel_trng_runtime_resume, NULL)
+ SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
+ pm_runtime_force_resume)
};
-#endif /* CONFIG_PM */
static const struct atmel_trng_data at91sam9g45_config = {
.has_half_rate = false,
@@ -185,9 +221,7 @@ static struct platform_driver atmel_trng_driver = {
.remove = atmel_trng_remove,
.driver = {
.name = "atmel-trng",
-#ifdef CONFIG_PM
- .pm = &atmel_trng_pm_ops,
-#endif /* CONFIG_PM */
+ .pm = pm_ptr(&atmel_trng_pm_ops),
.of_match_table = atmel_trng_dt_ids,
},
};
diff --git a/drivers/char/hw_random/cavium-rng-vf.c b/drivers/char/hw_random/cavium-rng-vf.c
index 6f66919652bf..7c55f4cf4a8b 100644
--- a/drivers/char/hw_random/cavium-rng-vf.c
+++ b/drivers/char/hw_random/cavium-rng-vf.c
@@ -179,7 +179,7 @@ static int cavium_map_pf_regs(struct cavium_rng *rng)
pdev = pci_get_device(PCI_VENDOR_ID_CAVIUM,
PCI_DEVID_CAVIUM_RNG_PF, NULL);
if (!pdev) {
- dev_err(&pdev->dev, "Cannot find RNG PF device\n");
+ pr_err("Cannot find RNG PF device\n");
return -EIO;
}
diff --git a/drivers/char/hw_random/core.c b/drivers/char/hw_random/core.c
index cfb085de876b..16f227b995e8 100644
--- a/drivers/char/hw_random/core.c
+++ b/drivers/char/hw_random/core.c
@@ -32,7 +32,7 @@ static struct hwrng *current_rng;
/* the current rng has been explicitly chosen by user via sysfs */
static int cur_rng_set_by_user;
static struct task_struct *hwrng_fill;
-/* list of registered rngs, sorted decending by quality */
+/* list of registered rngs */
static LIST_HEAD(rng_list);
/* Protects rng_list and current_rng */
static DEFINE_MUTEX(rng_mutex);
@@ -45,14 +45,14 @@ static unsigned short default_quality; /* = 0; default to "off" */
module_param(current_quality, ushort, 0644);
MODULE_PARM_DESC(current_quality,
- "current hwrng entropy estimation per 1024 bits of input");
+ "current hwrng entropy estimation per 1024 bits of input -- obsolete, use rng_quality instead");
module_param(default_quality, ushort, 0644);
MODULE_PARM_DESC(default_quality,
"default entropy content of hwrng per 1024 bits of input");
static void drop_current_rng(void);
static int hwrng_init(struct hwrng *rng);
-static void start_khwrngd(void);
+static void hwrng_manage_rngd(struct hwrng *rng);
static inline int rng_get_data(struct hwrng *rng, u8 *buffer, size_t size,
int wait);
@@ -65,13 +65,12 @@ static size_t rng_buffer_size(void)
static void add_early_randomness(struct hwrng *rng)
{
int bytes_read;
- size_t size = min_t(size_t, 16, rng_buffer_size());
mutex_lock(&reading_mutex);
- bytes_read = rng_get_data(rng, rng_buffer, size, 0);
+ bytes_read = rng_get_data(rng, rng_fillbuf, 32, 0);
mutex_unlock(&reading_mutex);
if (bytes_read > 0)
- add_device_randomness(rng_buffer, bytes_read);
+ add_device_randomness(rng_fillbuf, bytes_read);
}
static inline void cleanup_rng(struct kref *kref)
@@ -162,14 +161,13 @@ static int hwrng_init(struct hwrng *rng)
reinit_completion(&rng->cleanup_done);
skip_init:
- current_quality = rng->quality ? : default_quality;
- if (current_quality > 1024)
- current_quality = 1024;
+ if (!rng->quality)
+ rng->quality = default_quality;
+ if (rng->quality > 1024)
+ rng->quality = 1024;
+ current_quality = rng->quality; /* obsolete */
- if (current_quality == 0 && hwrng_fill)
- kthread_stop(hwrng_fill);
- if (current_quality > 0 && !hwrng_fill)
- start_khwrngd();
+ hwrng_manage_rngd(rng);
return 0;
}
@@ -299,24 +297,28 @@ static struct miscdevice rng_miscdev = {
static int enable_best_rng(void)
{
+ struct hwrng *rng, *new_rng = NULL;
int ret = -ENODEV;
BUG_ON(!mutex_is_locked(&rng_mutex));
- /* rng_list is sorted by quality, use the best (=first) one */
- if (!list_empty(&rng_list)) {
- struct hwrng *new_rng;
-
- new_rng = list_entry(rng_list.next, struct hwrng, list);
- ret = ((new_rng == current_rng) ? 0 : set_current_rng(new_rng));
- if (!ret)
- cur_rng_set_by_user = 0;
- } else {
+ /* no rng to use? */
+ if (list_empty(&rng_list)) {
drop_current_rng();
cur_rng_set_by_user = 0;
- ret = 0;
+ return 0;
+ }
+
+ /* use the rng which offers the best quality */
+ list_for_each_entry(rng, &rng_list, list) {
+ if (!new_rng || rng->quality > new_rng->quality)
+ new_rng = rng;
}
+ ret = ((new_rng == current_rng) ? 0 : set_current_rng(new_rng));
+ if (!ret)
+ cur_rng_set_by_user = 0;
+
return ret;
}
@@ -337,8 +339,9 @@ static ssize_t rng_current_store(struct device *dev,
} else {
list_for_each_entry(rng, &rng_list, list) {
if (sysfs_streq(rng->name, buf)) {
- cur_rng_set_by_user = 1;
err = set_current_rng(rng);
+ if (!err)
+ cur_rng_set_by_user = 1;
break;
}
}
@@ -400,14 +403,76 @@ static ssize_t rng_selected_show(struct device *dev,
return sysfs_emit(buf, "%d\n", cur_rng_set_by_user);
}
+static ssize_t rng_quality_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ ssize_t ret;
+ struct hwrng *rng;
+
+ rng = get_current_rng();
+ if (IS_ERR(rng))
+ return PTR_ERR(rng);
+
+ if (!rng) /* no need to put_rng */
+ return -ENODEV;
+
+ ret = sysfs_emit(buf, "%hu\n", rng->quality);
+ put_rng(rng);
+
+ return ret;
+}
+
+static ssize_t rng_quality_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t len)
+{
+ u16 quality;
+ int ret = -EINVAL;
+
+ if (len < 2)
+ return -EINVAL;
+
+ ret = mutex_lock_interruptible(&rng_mutex);
+ if (ret)
+ return -ERESTARTSYS;
+
+ ret = kstrtou16(buf, 0, &quality);
+ if (ret || quality > 1024) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ if (!current_rng) {
+ ret = -ENODEV;
+ goto out;
+ }
+
+ current_rng->quality = quality;
+ current_quality = quality; /* obsolete */
+
+ /* the best available RNG may have changed */
+ ret = enable_best_rng();
+
+ /* start/stop rngd if necessary */
+ if (current_rng)
+ hwrng_manage_rngd(current_rng);
+
+out:
+ mutex_unlock(&rng_mutex);
+ return ret ? ret : len;
+}
+
static DEVICE_ATTR_RW(rng_current);
static DEVICE_ATTR_RO(rng_available);
static DEVICE_ATTR_RO(rng_selected);
+static DEVICE_ATTR_RW(rng_quality);
static struct attribute *rng_dev_attrs[] = {
&dev_attr_rng_current.attr,
&dev_attr_rng_available.attr,
&dev_attr_rng_selected.attr,
+ &dev_attr_rng_quality.attr,
NULL
};
@@ -425,9 +490,11 @@ static int __init register_miscdev(void)
static int hwrng_fillfn(void *unused)
{
+ size_t entropy, entropy_credit = 0; /* in 1/1024 of a bit */
long rc;
while (!kthread_should_stop()) {
+ unsigned short quality;
struct hwrng *rng;
rng = get_current_rng();
@@ -436,27 +503,49 @@ static int hwrng_fillfn(void *unused)
mutex_lock(&reading_mutex);
rc = rng_get_data(rng, rng_fillbuf,
rng_buffer_size(), 1);
+ if (current_quality != rng->quality)
+ rng->quality = current_quality; /* obsolete */
+ quality = rng->quality;
mutex_unlock(&reading_mutex);
put_rng(rng);
+
+ if (!quality)
+ break;
+
if (rc <= 0) {
pr_warn("hwrng: no data available\n");
msleep_interruptible(10000);
continue;
}
+
+ /* If we cannot credit at least one bit of entropy,
+ * keep track of the remainder for the next iteration
+ */
+ entropy = rc * quality * 8 + entropy_credit;
+ if ((entropy >> 10) == 0)
+ entropy_credit = entropy;
+
/* Outside lock, sure, but y'know: randomness. */
add_hwgenerator_randomness((void *)rng_fillbuf, rc,
- rc * current_quality * 8 >> 10);
+ entropy >> 10);
}
hwrng_fill = NULL;
return 0;
}
-static void start_khwrngd(void)
+static void hwrng_manage_rngd(struct hwrng *rng)
{
- hwrng_fill = kthread_run(hwrng_fillfn, NULL, "hwrng");
- if (IS_ERR(hwrng_fill)) {
- pr_err("hwrng_fill thread creation failed\n");
- hwrng_fill = NULL;
+ if (WARN_ON(!mutex_is_locked(&rng_mutex)))
+ return;
+
+ if (rng->quality == 0 && hwrng_fill)
+ kthread_stop(hwrng_fill);
+ if (rng->quality > 0 && !hwrng_fill) {
+ hwrng_fill = kthread_run(hwrng_fillfn, NULL, "hwrng");
+ if (IS_ERR(hwrng_fill)) {
+ pr_err("hwrng_fill thread creation failed\n");
+ hwrng_fill = NULL;
+ }
}
}
@@ -464,7 +553,6 @@ int hwrng_register(struct hwrng *rng)
{
int err = -EINVAL;
struct hwrng *tmp;
- struct list_head *rng_list_ptr;
bool is_new_current = false;
if (!rng->name || (!rng->data_read && !rng->read))
@@ -478,18 +566,11 @@ int hwrng_register(struct hwrng *rng)
if (strcmp(tmp->name, rng->name) == 0)
goto out_unlock;
}
+ list_add_tail(&rng->list, &rng_list);
init_completion(&rng->cleanup_done);
complete(&rng->cleanup_done);
- /* rng_list is sorted by decreasing quality */
- list_for_each(rng_list_ptr, &rng_list) {
- tmp = list_entry(rng_list_ptr, struct hwrng, list);
- if (tmp->quality < rng->quality)
- break;
- }
- list_add_tail(&rng->list, rng_list_ptr);
-
if (!current_rng ||
(!cur_rng_set_by_user && rng->quality > current_rng->quality)) {
/*
@@ -639,7 +720,7 @@ static void __exit hwrng_modexit(void)
unregister_miscdev();
}
-module_init(hwrng_modinit);
+fs_initcall(hwrng_modinit); /* depends on misc_register() */
module_exit(hwrng_modexit);
MODULE_DESCRIPTION("H/W Random Number Generator (RNG) driver");
diff --git a/drivers/char/hw_random/nomadik-rng.c b/drivers/char/hw_random/nomadik-rng.c
index 67947a19aa22..e8f9621e7954 100644
--- a/drivers/char/hw_random/nomadik-rng.c
+++ b/drivers/char/hw_random/nomadik-rng.c
@@ -65,14 +65,14 @@ static int nmk_rng_probe(struct amba_device *dev, const struct amba_id *id)
out_release:
amba_release_regions(dev);
out_clk:
- clk_disable(rng_clk);
+ clk_disable_unprepare(rng_clk);
return ret;
}
static void nmk_rng_remove(struct amba_device *dev)
{
amba_release_regions(dev);
- clk_disable(rng_clk);
+ clk_disable_unprepare(rng_clk);
}
static const struct amba_id nmk_rng_ids[] = {